31st International Workshop on Deep Inelastic Scattering

8 avr. 2024, 07:40 → 12 avr. 2024, 17:30 Europe/Paris

Maison MINATEC, Grenoble, FRANCE

The deadline for early registration has been moved to Friday 23 February.

The XXXI International Workshop on Deep Inelastic Scattering and Related Subjects (DIS2024) will be organized in Grenoble, France, from April 8 to April 12, 2024.

The conference covers a large spectrum of topics in high energy physics. A significant part of the program is devoted to the most recent theoretical advances and results from large experiments at BNL, CERN, DESY, FNAL, JLab and KEK. 

The venue of the workshop is the Maison MINATEC  congress center which is part of the scientific area Grenoble Presqu'Île close to the city center.

http://dis2024.org

lundi 8 avril

07:40 Breakfast/Registration

Plenary

Président de session: Cynthia Keppel (Thomas Jefferson National Accelerator Facility)

1 Welcome from UGA

Orateur: Yannick Vallée (UGA)

2 Welcome from the Organizers

Orateurs: Johann Collot, Ingo Schienbein

Welcome_DIS2024.pdf

3 Global analysis of PDFs

Orateur: Lucian Harland-Lang (University College London)

lhl_DIS2024_v1.pdf

4 Global analysis of nuclear PDFs

Orateur: Michael Klasen

klasen_dis24_v02.pdf

5 3D structure of hadrons

Orateur: Cedric Lorce (IPNO and LPT, Paris-Sud University)

DIS2024_Lorce.pdf

10:30 Coffee break

Plenary: 3

Président de session: Jean-Philippe Guillet

6 Theoretical advances in electroweak, Higgs and top physics at the LHC

Orateur: Mathieu Pellen (University of Freiburg)

PELLEN_DIS.pdf

7 Highlight and prospects on electroweak and top physics at the (HL-)LHC

Orateur: Kajari Mazumdar (Tata Institute of Fundamental Research-B, Mumbai, India)

DIS_KM.pdf

8 Highlights and prospects on Higgs physics at the (HL-)LHC

Orateur: Julian Wollrath

Higgs_Highlights_Prospects_HLLHC_Wollrath.pdf

12:30 Lunch

Plenary: 2

Président de session: Pavel Nadolsky (Southern Methodist University)

9 Low-x and forward physics

Orateur: Ronan McNulty

dis_mcnulty_3.pdf

10 EIC, HL-LHC, Forward physics

Orateur: Charlotte van Hulse

DIS_Charlotte.pdf

11 Highlights in heavy ion physics at the LHC

Orateur: Friederike Bock

DIS_HIatLHC_v1.pdf

15:30 Coffe break

Plenary: 4

Président de session: Juan Rojo (VU Amsterdam and Nikhef)

12 Altarelli Prize Ceremony

Orateur: Fredrick Olness (SMU)

AltarelliAward_GroupPhoto_2024.jpg

AltarelliAwardNews2024.pdf

AltarelliAwardSlides_2024.pdf

YouTube Video link of Award Ceremony

13 QCD for precision neutrino physics

Orateur: Un-ki Yang (Seoul National University)

DIS24_ukyang_v2.pdf

14 Anomalies

Orateur: Andreas Crivellin (UZH & PSI)

DIS2024.pptx

18:30 Welcome Reception

mardi 9 avril

WG1: Structure Functions and Parton Densities 1

15 Progress in the CTEQ-TEA global QCD analysis

I report on the progress in the precision studies of hadronic parton distributions by the CTEQ-TEA (Tung Et Al.) group.

Orateur: Pavel Nadolsky (Southern Methodist University)

o409_grenoble.pdf

16 Updates of MSHT PDFs

In this talk we will summarise the latest updates to PDF fits using the MSHT
approach. This will include details of high-x PDF sensitivity to jet/dijet
data, Z boson transverse distributions and high x data providing information
on quark flavours. We will also discuss the most recent determinations of
the strong coupling constant at both NNLO and N^3LO in perturbation theory.
We will summarise the inclusion of QED corrections and the photon PDF into
the approximate N^3LO framework. Finally, we will mention progress involving
improvements to the approximate N^3LO PDF analysis.

Orateur: Robert Thorne (University College London)

DIS2024MSHT.pdf

17 NNPDF progress and the path to proton structure at N3LO accuracy

I present recent progress in the framework of the NNPDF global PDF analyses. These include a determination of proton structure at aN3LO accuracy and the assessment of its implications for N3LO cross-sections at the LHC; NNPDF4.0 variants with QED effects and missing higher order uncertainties accounted for; the intrinsic valence charm content of the proton; selected methodological studies; and the inclusion of legacy LHC Run II measurements in the global fit. Two companion talks present i) a systematic comparisons of global NNLO PDF fits with the most precise measurements from the LHC, and ii) a preliminary version of a new global polarised NNPDF determination.

Orateur: Juan Rojo (VU Amsterdam and Nikhef)

rojo-DIS2024-nnpdf.pdf

18 LHC differential top-quark pair production cross sections in the ABMP16 PDF fit

We investigate the impact of recent LHC measurements of differential top-quark pair production cross sections on the proton parton distribution functions (PDFs) using the ABMP16 methodology. The theoretical predictions are computed at NNLO QCD using the state-of-the-art MATRIX framework. The top-quark mass and strong coupling constants are free parameters of the fit, and we pay particular attention to the values of these parameters and their correlation as obtained from variants of the fit using different input data sets. We discuss the compatibility of different datasets and the compatibility of the fitted PDFs with those extracted from other datasets in the global ABMP16 fit, as well as with other modern global PDF sets. In addition, we compare the fit results with those obtained using the open-source xFitter framework.

Orateur: Oleksandr Zenaiev (Hamburg University)

Zenaiev-DIS-ttbar.pdf

19 xFitter Updates: Probing Z Boson Couplings with Forward-Backward Asymmetry

We present recent updates in the xFitter software framework for global fits of parton distribution functions (PDFs) in high-energy physics. Our focus is on investigating the sensitivity to Z boson couplings using the forward-backward asymmetry in Drell-Yan production. By utilizing an effective approach and simulated data, we assess the accuracy of these couplings, specifically considering the full LHC data sample. Furthermore, we compare our results with predictions for future colliders, providing insights into their potential impact on understanding Z boson interactions.

Orateur: Oleksandr Zenaiev (DESY)

Zenaiev-DIS-afb.pdf

10:30 Coffe break

20 Phenomenological implications of modern PDF determinations

In recent years, precision in PDF determinations has significantly improved due to a combination of experimental (better statistics, control over uncertainties) and theoretical improvements (NNLO predictions, N3LO splitting functions). Thanks to this enhanced precision,
differences in the methodologies, data treatment and theory choices can now be resolved between different fitting collaborations. Differences which could have a phenomenological impact.
In this talk, I will discuss a systematic study carried out by the NNPDF collaboration on the data-theory agreement of a selection of observables from LHC Run II which are not yet included in PDF determinations.
In this quantitative study we present NNLO predictions for different PDF inputs and compare them to the latest data available.

Orateur: Juan Manuel Cruz Martinez (CERN)

juanCM_pheno.pdf

21 Impact of new data on the gluon PDF in NNPDF 4.0

We study the impact of new data sets on the NNPDF4.0 PDF determination. Specifically, we consider measurements for processes that are sensitive to the gluon PDF: legacy H1 and ZEUS DIS + jet and DIS + dijet production and Run II ATLAS and CMS single-inclusive jet, dijet, and top pair production. We take into account theory uncertainties in PDF evolution and in the cross-section matrix elements. We examine the consistency of the data sets and how these affect the gluon PDF.

Orateur: Tanishq Sharma

Impact of new data on the gluon PDF-dis workshop.pdf

22 CMS jet measurements and constraints on PDFs and alphaS

Recent measurements of jet cross sections in proton-proton collisions with the CMS experiment are presented. The measured jet cross sections are corrected for detector effects and compared with the predictions from perturbative QCD, and exploited to derive constraints on parton distribution functions and to mesure alpha_S.

Orateur: Daniel Savoiu (University of Hamburg)

dis2024_dsavoiu_cms_jet_measurements.pdf

23 New Measurements of the Deuteron to Hydrogen F2 Structure Function Ratio

Nucleon structure functions, as measured in lepton-nucleon scattering, have historically provided a critical observable in the study of partonic dynamics within the nucleon. However, at very large parton momenta it is experimentally and theoretically challenging to extract parton distributions due to the onset of non-perturbative contributions. New results will be presented from experiment E12-10-002 carried out in Jefferson Lab Experimental Hall C on the deuteron to proton cross–section ratio at large Bjorken-x that significantly improves on the precision of existing data, as well as a first look at the expected impact on quark distributions extracted from global parton distribution function fits.

Orateur: William Henry (Jefferson Lab)

henry_DIS2024.pdf

24 New Neutron Structure Function Extraction from Global Inclusive Proton and Deuteron Data

The available world deep-inelastic scattering data on the proton and deuteron structure functions F2p and F2d, and the ratio F2p/F2d, were leveraged to extract the free neutron structure function, F2n, and associated uncertainties using the latest nuclear effects calculations with the deuteron data. Special attention was devoted to the normalization of the proton and deuteron experimental datasets and to the treatment of correlated systematic errors, as well as the quantification of procedural and theoretical uncertainties. The extracted F2n dataset is utilized to evaluate the Q2 dependence of the Gottfried Sum Rule and the nonsinglet F2p-F2n moments. To facilitate replication of this study, as well as for general applications, a comprehensive database including all recent JLab measurements, the extracted F2n, a modified CTEQ-JLab global PDF fit named CJ15nlo mod, and grids with calculated proton, neutron and deuteron structure functions at next-to-leading order, have been made publicly available. A summary overview of this work will be presented.

Orateurs: Cynthia Keppel (Thomas Jefferson National Accelerator Facility), Shujie Li

f2n-DIS2024-ShujieLi (1).pdf

WG2: Small-x, Diffraction and Vector Mesons 1

25 Introduction to WG2 program

Orateurs: Cristian Baldenegro (Sapienza Università di Roma (IT)), Pieter Taels (University of Antwerp), Renaud Boussarie (CPHT, CNRS, Ecole polytechnique, IP Paris)

WG2_introduction

26 Ultraperipheral Collisions at LHCb

Orateurs: Cesar Da Silva (Los Alamos National Laboratory), Cesar da Silva (Los Alamos National Lab)

DIS2024-UPC-LHCb-v2.pdf

27 Probing gluon saturation with novel ratio observables in ultra-peripheral collisions

Orateur: Zhoudunming Tu (BNL)

slides_Tu_upload.pdf

28 Inclusive photoproduction of vector quarkonium in ultra-peripheral collisions at the LHC

Orateur: Kate Lynch (UC Dublin and Paris-Saclay University IJClab)

Inclusive_UPC___LHC-1.pdf

10:30 Coffee break

29 Diffractive measurements at CMS

Orateur: Michael Pitt (Ben Gurion University of the Negev (IL))

CMS_Diffractive_MPitt.pdf

30 Scaling laws of differential elastic pp cross-section

Orateur: Michal Praszalowicz (Jagiellonian University)

praszalowicz_DIS_2024.pdf

31 Extracting the partonic structure of colorless exchanges in diffraction at the EIC

Orateur: Anna Stasto (Penn State)

Anna_Stasto_reggeons.pdf

32 Dipole picture diffractive structure function at NLO

Orateur: Tuomas Lappi (University of Jyväskylä)

dis24.pdf

33 TMD factorisation for diffractive jets in photon-nucleus interaction

Orateur: Sigtryggur Hauksson (IPhT, CEA, Université Paris-Saclay)

DIS_2024_Hauksson_new.pdf

WG3: Electroweak Physics and Beyond the Standard Model 1: Higgs Physics

34 Measurements of the Higgs boson mass and natural width with the ATLAS detector

This talk presents precise measurements of the mass and natural width of the Higgs boson, obtained using the full dataset collected in pp collisions at 13 TeV during Run 2 of the LHC. The measurements are performed in various Higgs boson production and decay modes, as well as their combinations. The talk will describe the adopted analysis strategies, and it will stress the impact of the experimental techniques on these measurements.

Orateur: Leonardo Carminati

HiggsBosonMassATLAS_Carminati.pdf

35 Higgs boson mass and width measurement at CMS

The characterisation of the Higgs boson relies on the determination of all the properties of this particle, including its mass, which is a free parameter in the SM, and its width. This presentation will discuss the latest developments in measurements of the Higgs boson mass and width with the four-lepton and di-photon final state, with data collected by the CMS experiment at a centre of mass energy of 13 TeV. Both direct and indirect constraints on the Higgs boson width will be shown.

Orateur: Antonio Vagnerini

Vagnerini_DIS2024.pdf

36 Higgs boson coupling properties to fermions and search for rare and LFV Higgs boson decays with ATLAS

The Yukawa couplings of the Higgs boson to quarks and leptons are an important window into the mechanism of electroweak symmetry breaking and the origin of fermion masses. This talk presents several measurements of Higgs boson decays to bottom quarks, tau leptons and muons, as well as constraints on the rate of Higgs boson decays to charm quarks and on the magnitude of the charm-Yukawa coupling. The production of Higgs bosons in association with top quarks will also be discussed. These results are based on the full dataset collected in pp collisions at 13 TeV during Run 2 of the LHC.

Orateur: Louis-Guillaume Gagnon

2024-04-09_DIS2024_Higgs_gagnonlg_draft4.pdf

37 Measurement of the Higgs boson cross sections with H->gamma gamma decays at CMS

After the discovery of the Higgs boson with LHC Run-1 data, its production cross sections have been measured at the increasing centre-of-mass energies that were reached in LHC proton-proton collisions. Comparisons with theoretical calculations so far confirm the predictions of the Standard Model. The diphoton decay channel offers a clean final state and relatively high event rate, allowing both the measurement of total cross section in a fiducial phase space defined at particle level with a small dataset, as well as precise differential cross sections with larger datasets. These measurements give the possibility of precise comparisons with Standard Model predictions.

Orateur: Johannes Erdmann

DIS2024.pdf

38 Towards Higgs and Z boson plus jet distributions at NLL/NLO+

Recent analyses on high-energy inclusive Higgs-boson rates in proton collisions, matched with the state of-the-art fixed-order N$^3$LO accuracy, have shown that the impact of high-energy resummation corrections reaches 10% at the FCC nominal energies. This supports the statement that electroweak physics at 100 TeV is expected to receive relevant contributions from small-$x$ physics. In this talk we will present novel predictions for rapidity and transverse-momentum distributions sensitive to the emission of a Higgs boson accompanied by a jet in proton collisions, calculated within the NLO fixed order in QCD and matched with the next-to leading energy-logarithmic accuracy and beyond (NLL/NLO$^+$). We will also highlight first advancements in the extension of our analysis to the $Z$-boson case. According to our knowledge, this represent a first and novel implementation of a matching procedure in the context of the high-energy resummation for rapidity-separated two-particle final states. We come out with the message that the improvement of fixed-order calculations on Higgs- and Z-boson plus jet distributions is a core ingredient to reach the precision level of the description of observables relevant for Higgs and electroweak physics at current LHC energies as well as at nominal FCC ones.

Orateur: Francesco Giovanni Celiberto (UAH Madrid)

talk_DIS_2024_HZ-jet_NLL-NLO_Celiberto.pdf

10:40 Coffee break

39 Higgs boson differential cross section measurements at CMS

We will present the latest differential measurements of Higgs boson cross sections with the CMS detector. Both fiducial differential cross section measurements and measurements in the simplified template cross section framework will be discussed, analyzing several decay modes of the Higgs boson. The data collected during Run 2 of the LHC by the CMS experiment are used. We also present interpretations of these measurements as constraints on anomalous interactions.

Orateur: Alessandra Cappati (LLR, Ecole Polytechnique, IN2P3-CNRS)

DIS_Cappati.pdf

40 Measurements of Higgs boson cross-sections and their interpretation with the ATLAS experiment

Measurements of total, fiducial, and differential cross-sections offer a key window into the properties of Higgs boson production and decay at the LHC. This talk presents results obtained using the full dataset collected in pp collisions at 13 TeV during Run 2 of the LHC in various production and decay processes, providing fine-grained description of their kinematics and associated production. Interpretations of these measurements within the framework of Standard Model Effective Field Theories are also shown.

Orateur: Benedict Tobias Winter

DIS2024talk_bwinter.pdf

41 EFT interpretations in the Higgs sector at CMS

Effective Field Theories provide an interesting way to parameterize indirect BSM physics, when its characteristic scale is larger than the one directly accessible at the LHC, for a large class of models. Even if the Higgs boson is SM-like, BSM effects can manifest itself through higher-dimension effective interactions between SM fields, providing indirect sensitivity through distortions of kinematic distributions. Constraints on such effects derived by measurements of several production and decay modes of the Higgs boson and their combination on the data set collected by the CMS experiment a centre of mass energy of 13 TeV will be presented.

Orateur: Oguz Guzel

Higgs-EFT-at-CMS_Oguz_Guzel_DIS02024.pdf

42 Searching for additional Higgs bosons at ATLAS

The discovery of the Higgs boson with the mass of about 125 GeV completed the particle content predicted by the Standard Model. Even though this model is well established and consistent with many measurements, it is not capable to solely explain some observations. Many extensions of the Standard Model addressing such shortcomings introduce additional Higgs-like bosons which can be either neutral or charged. The current status of searches for additional low- and high-mass Higgs bosons based on the full LHC Run 2 dataset of the ATLAS experiment at 13 TeV are presented.

Orateur: Asma Hadef

Asma_Hadef_Searching_for_additional_Higgs_bosons_at_ATLAS.pdf

43 New Higgses at the electroweak scale

Many LHC measurements with multi-lepton final states and missing energy, in particular top differential distributions, show strong tensions with the SM predictions. I discuss how they can be explained by new physics within the Delta2HDMS and show the correlations to the hints for narrow resonances at the electroweak scale.

Orateur: Andreas Crivellin (UZH & PSI)

DIS2.pdf

MoriondEW2024.pptx

WG4: QCD with Heavy Flavours and Hadronic Final States 1

44 Precise phenomenology at the LHC: state of art in perturbative QCD

Significant progress has been made in the calculation and evaluation of multi-loop QCD (and EW) scattering amplitudes, as well as the development of effective subtraction methods in (N)NNLO QCD. As a result, the level of precision of theoretical predictions for many relevant processes at the Large Hadron Collider has been significantly improved. In this review, we will discuss the latest fixed-order calculations in higher-order perturbative QCD and their impact on the LHC phenomenology.

Orateur: Luca Buonocore (CERN)

DIS24_FOTHrev.pdf

45 Open bottom production at hadron colliders at NNLO+NNLL

In this talk, I will present the results of the first
calculation of open bottom production at hadron colliders at NNLO+NNLL,
i.e. a next-to-next-to-leading-order calculation that resums collinear
logarithms at next-to-next-to-leading-logarithmic accuracy. This new
computation achieves significantly reduced theory errors compared to
previous calculations, with errors of just a few percent at high
transverse momenta. These results are compared to data from a vast
amount of measurements performed at the Tevatron, where lower-order
predictions have previously been found to underestimate the cross
section. To perform such comparisons, the hadronisation and decay of the
b-quark is included in the theory calculation where needed, yielding
predictions for a wide range of final states.

Orateur: Terry Generet (University of Cambridge)

Generet.pdf

46 Recent results on open heavy flavor production (pp, pPb, PbPb) from LHCb

Heavy quarks are produced in the early stages of heavy ion collisions due to their large mass, and subsequently traverse the entire QCD medium evolution.
The open heavy flavor hadron ratio provides profound insights into the heavy quark hadronization mechanisms . By comparing these ratios in different collision systems, which reveal the contribution of the coalescence mechanism in different medium.
In the lhcb experiment, fixed-target collisions cover an unexplored energy range that is above previous fixed-target experiments, but below the top RHIC energy for AA collisions.
In pPb collisions, heavy quarks are crucial to study cold nuclear matter effects, which include the modification of nuclear parton distribution functions, energy loss in the nucleus, and other effects, providing a baseline for interpreting PbPb measurements.

Orateur: Chenxi Gu

DIS2024_ChenxiGu.pdf

47 Recent heavy-flavour results from ATLAS

Recent results from ATLAS on heavy flavours are presented. They include measurement of $B^0$ lifetime, effective lifetime in $B^0_s\to\mu^+\mu^-$ decay, measurement of prompt and non-prompt charmonium production and studies of exotic contributions in low-mass four-muon final state.

Orateur: Semen Turchikhin

Turchikhin_ATLAS_HeavyFlavour.pdf

10:30 Coffee break

48 Recent heavy-flavor measurements from RHIC

Heavy quarks are predominantly produced in the initial hard partonic scatterings, and thus their production cross-section can be calculated by pQCD.
Quarkonia and heavy-flavor hadrons can also be employed as tools for investigating heavy-quark dynamics in Quark-Gluon Plasma created in heavy-ion collisions. The changes in the production rate of quarkonia in the QGP are indicative of the effects of both static and dynamic dissociation processes induced by the medium, as well as contributions from regeneration. On the other hand, the reduction in production rate and the directional asymmetry of open heavy flavor are linked to the heavy-quark energy loss and the level of thermalization in the QGP medium.

In this contribution, the recent open heavy flavor and quarkonia measurements in p+p and heavy-ion collisions from RHIC will be discussed.

Orateur: Veronika Prozorova (Czech Technical University in Prague FNSPE)

DIS2024_HFfromSTAR.pdf

49 Reacent heavy flavour measurements from ALICE

The transverse momentum (pT) differential production cross section of the promptly-produced charm-strange baryon Ξ0c is measured at midrapidity via its hadronic decay into π+Ξ− in p–Pb collisions at sqr(sNN) = 5.02 TeV with the ALICE detector at the LHC. The Ξ0c nuclear modification factor (RpPb), calculated from the cross sections in pp and p–Pb collisions, is presented and compared with the RpPb of Λ+c baryons. The ratios between the pT-differential production cross section of Ξ0c baryons and those of D0 mesons and Λ+c baryons are also reported and compared with results from the LHCb Collaboration. The measurements are compared with a model based on perturbative QCD calculations of charm quark production cross sections including only cold nuclear matter effects in p–Pb collisions, which underestimates the measurement by a factor of about 50. This discrepancy is reduced when the data is compared with a model in which hadronisation is implemented via quark coalescence. The pT-integrated cross section of prompt Ξ0c-baryon production at midrapidity is also reported. These results provide important inputs for the calculation of the charm production cross section in p–Pb collisions at midrapidity.

Orateur: Jonghan Park

240409_DIS.pdf

50 Charm total cross sections and extraction of QCD parameters

The usage of charm cross sections from hadron-hadron collisions for
the extraction of perturbative QCD parameters has recently been hampered by
evidence that charm quark fragmentation into charm hadrons is nonuniversal,
i.e. may depend on the collision initial and final state and its energy.
Fragmentation effects can be eliminated from the theory by considering the
total ccbar pair cross section only, currently calculable e.g. in pp collisions
at NNLO QCD.
Comparison to experiment then needs the extrapolation of measured fiducial
charm cross sections to the total ccbar pair cross section, again hitting the
charm fragmentation nonuniversality problem.
In [1], a first preliminary version of a new procedure to obtain such an
extrapolation based on an "effective" variant of the well-known differential
FONLL QCD calculation has been presented. This procedure obtains an effective
shape and normalization of theory-inspired extrapolation functions, based on
constraints obtained from various published measurements. Within uncertainties,
it fully accounts for charm fragmentation nonuniversality, without the need to
assume any particular nonuniversal charm fragmentation model.
This new procedure is now elaborated further, and applied to total charm cross
section evaluations at different LHC hadron-hadron collision energies.
From the dependence of these total charm cross sections on center of mass,
in which the large QCD scale dependence partially cancels, first results on
constraining QCD parameters like parton density functions and the charm
quark mass at NNLO are presented, superseding all previous results still
based on the charm quark fragmentation universality assumption.

Orateur: Achim Geiser (DESY)

CharmDIS24_3.pdf

51 PineAPPL grids of open heavy-flavor production in the GM-VFNS

Many next-to-leading order QCD predictions are available through Monte Carlo (MC) simulations. Usually multiple CPU-hours are needed to calculate the physical predictions at a feasible precision and are therefore impractical for global PDF analyses. This problem is solved by a process known as "gridding": The values of the hard-scattering cross-section are calculated only once with the MC program, and then interpolated and stored in look-up tables (grids) of the kinematical variables. To obtain the physical predictions, they are convoluted with the PDFs (e.g. during the fitting stage in a PDF global analysis), which takes a tiny fraction of the time needed to calculate the MC results. This is possible with PineAPPL, a new library tackling the aforementioned process of grid creation and convolution. In this work, we use PineAPPL to grid the predictions for open heavy-flavor production in the general-mass variable-flavor-number scheme (GM-VFNS). In the GM-VFNS, the differential cross-section interpolates between the fixed-flavor-number scheme (FFNS) and the zero-mass variable-flavor-number scheme (ZM-VFNS). These are each only valid in different kinematical regions, in which the GM-VFNS cross-section reproduces the FFNS and ZM-VFNS as the limiting cases of high energies and small masses, respectively. Better than per-mille agreement is achieved between the grids and the MC predictions, while at the same time not substantially increasing the time of the MC calculations.

Orateur: Jan Wissmann (Universität Münster)

wissmann_dis2024.pdf

WG5: Spin and 3D Structure 1

52 Nucleon spin and 3D structure studies at COMPASS

COMPASS is the longest-running experiment at CERN, with a record-breaking 20 years of data collection from 2002 to 2022. The experiment has a unique and diverse physics programme focused on nucleon structure and spectroscopy measurements.

The experimental results obtained by COMPASS during Phase I (2002-2011) and Phase II (2012-2022) for a wide range of nucleon spin structure-related DIS and Drell-Yan measurements play an essential role in the general understanding of the three-dimensional nature of the nucleon. In 2022, the experiment performed its last highly successful data taking dedicated to the study of transverse spin phenomena in semi-inclusive measurements of hadron production in DIS using a high energy muon beam and a transversely polarised deuteron target.

This talk will review selected highlights from the COMPASS legacy on nucleon spin structure studies and address recent results and prospects.

Orateur: Bakur Parsamyan (AANL, CERN and INFN-Turin)

Parsamyan_DIS-2024.pdf

53 Exclusives with Artificial Intelligence and Machine learning

Understanding the 3D structure of visible matter in the universe while advancing the tomography of nucleons is one of the central goals of contemporary nuclear physics, pursued at the upgraded 12 GeV Jefferson Lab accelerator and at the planned Electron-Ion Collider (EIC). To fully capitalize on the data emerging from these experiments and to guide their extraction, the DOE-funded EXCLusives via Artificial Intelligence and Machine learning (EXCLAIM) collaboration is developing a framework for the next-generation precision characterization of the quark-gluon structure of matter. Central to our initiative is the design of physics informed deep learning architectures that, unlike standard “black box” methods, are crafted for specific physics purposes using more flexible and physically explainable ML building blocks. This program requires a joint effort of ML experts and nuclear theorists/experimentalists to work together in interdisciplinary collaborative work. Our approach to 3D hadron structure aims at providing the technology to continually incorporate both the latest experimental data and precision first-principle Lattice QCD (LQCD) calculations. We will present a benchmark system to track the behavior of various asymmetries for Deeply Virtual Exclusive Scattering (DVES) processes, enlarging the scope of the tomographic explorations to include processes characterized by multi-particle final states many-body correlations.

Orateur: Yaohang Li (ODU)

54 Hard exclusive pi0 muoproduction cross-section at COMPASS

Hard exclusive meson production is one of the common approaches to constrain Generalised Parton Distributions. Such exclusive measurement and notably exclusive $\pi^{0}$ production were conducted at COMPASS in 2016 and 2017 at the M2 beamline from the CERN SPS using the 160 GeV/$c$ muon beam scattering off a 2.5~m long liquid hydrogen target inserted into a~barrel-shaped time-of-flight detector to record the recoiling target proton. The outgoing photons from the exclusive $\pi^0$ decay were detected by a calorimetry system consisting of large-angle and small-angle calorimeters, and the scattered muon was recorded by the COMPASS spectrometer equipped with about 350~tracking planes.

Exclusive $\pi^{0}$ production is a concurrent process of deeply virtual Compton scattering and provides complementary information for the parametrisation of generalised parton distributions, as well as for their flavour dependency. We will report on the preliminary results on exclusive $\pi^0$ production cross-section from 2016 data dependent on the squared four-momentum transfer $|t|$ and on the azimuthal angle $\phi$ between the scattering plane and the $\pi^0$ production plane. The results will provide a further input to phenomenological models for constraining generalised parton distributions, in particular chiral-odd ("transversity") ones.

Orateur: Marketa Peskova (Charles University)

Exclusive_pi0_COMPASS_Peskova_DIS2024.pdf

55 Spin Density Matrix Elements in hard exclusive $\phi$ meson muoproduction at COMPASS

We will present preliminary results on Spin Density Matrix Elements (SDMEs) measured in hard exclusive $\phi$ meson muoproduction on protons at COMPASS using 160 GeV/$c$ polarised $\mu ^{+}$ and $\mu ^{-}$ beams scattering off a liquid hydrogen target. The measurements cover the range 6 GeV/$c^2$ < W < 17 GeV/$c^2$, 1.0 (GeV/$c$)$^2 <$ Q$^2 <$ 10.0 (GeV/$c$)$^2$ and 0.01 (GeV/$c$)$^2$ < p$_\rm{T}$ < 0.5 (GeV/c)$^2$. Here, Q$^2$ denotes the virtuality of exchanged photon, W the mass of final hadronic system and p$_\rm{T}$ the transverse momentum of the vector meson with respect to the virtual-photon direction. The measured non-zero SDMEs for transitions of transversely polarised virtual photons to longitudinally polarised vector mesons ($\gamma _{\rm{T}}$ $\rightarrow$ V{$_\rm{L}$) indicate a violation of s-channel helicity conservation. Additionally, we observe a dominant contribution of natural-parity-exchange transitions and a small contribution of unnatural-parity-exchange transitions. These results, combined with the published COMPASS results on SDMEs in exclusive $\rho ^0$ and $\omega$ productions, may provide an important input for modelling Generalised Parton Distribution (GPDs). In particular, they may allow to estimate the role of parton-helicity flip GPDs ("transversity GPDs") for the quarks of dfferent flavours and for gluons.

Orateur: Dr Witold Augustyniak (National Centre for Nuclear Research)

10:30 Coffee Break

56 Anomalous dimensions for hard exclusive processes

We give an overview of recent developments in the computation of the anomalous dimension matrix of composite operators in non-forward kinematics. The elements of this matrix determine the scale dependence of non-perturbative parton distributions, such as GPDs, and hence constitute important input for phenomenological studies of exclusive processes like deeply-virtual Compton scattering. Particular emphasis will be put on a recently developed method that exploits consistency relations for the anomalous dimension matrix which follow from the renormalization structure of the operators.

Orateur: Sam Van Thurenhout (HUN-REN Wigner RCP)

Anomalous_dimensions_for_hard_exclusive_processes_DIS2024.pdf

57 Accessing Generalized Parton Distributions through 2 -> 3 exclusive processes

We review our results on a new class of 2 -> 3 exclusive processes, as a probe of both chiral-even and chiral-odd quark GPDs. We consider the exclusive photoproduction of a photon-meson pair, in the kinematics where the pair has a large invariant mass, described in the collinear factorization framework. We cover the whole kinematical range from medium energies in fixed target experiments to very large energies of colliders, by considering the experimental conditions of JLab 12-GeV, COMPASS, future EIC and LHC (in ultra-peripheral collisions) cases. Our analysis covers neutral and charged rho-mesons, as well as charged pions. In the case of the rho-meson, depending on its polarization, this provides access to either chiral-even or chiral-odd GPDs, at leading twist. We find that the order of magnitude of the obtained cross sections are sufficiently large for a dedicated experimental analysis to be performed, especially at JLab. Furthermore, we compute the linear photon beam polarization asymmetry, which we find to be sizeable, in the case of a longitudinally polarized rho meson or of a charged pion. These predictions are obtained for both asymptotic distribution amplitude (DA) and holographic DA.

Orateur: Samuel Wallon (IJCLab)

DIS-9-4-2024-Samuel-Wallon.pdf

58 A study of gluon distributions inside the proton

We formulate a light-front spectator model for the proton incorporating the gluonic degree of freedom. We investigate the helicity distribution which is consistent with existing experimental data and satisfies the perturbative QCD constraints at small and large longitudinal momentum of gluon in this model. We present the transverse momentum dependent distributions (TMDs) for gluon in this model. In terms of GPDs at non-zero skewness, we also investigate the entire three-dimensional representation of gluons. We address the total angular momentum contribution of the gluons by using the Ji's sum rules and also give our predictions for the kinetic orbital angular momentum in the light-cone gauge.

Orateur: Poonam Choudhary (IIT Kanpur)

DIS_TALK.pdf

59 Probing quark orbital angular momentum in ep collisions

We propose to extract quark orbital angular momentum (OAM) through exclusive $\pi^0$ production in electron-(longitudinally-polarized) proton collisions. Our analysis demonstrates that the $\rm sin(2\phi)$ azimuthal angular correlation between the transverse momentum of the scattered electron and the recoil proton serves as a sensitive probe of quark OAM. Additionally, we present a numerical estimate of the asymmetry associated with this correlation for the kinematics accessible at EIC and EicC. This study aims to pave the way for the first measurement of quark OAM in relation to the JaffeManohar spin sum rule.

Orateur: Shohini Bhattacharya

DIS24_SB.pdf

60 Sensitivity of DDVCS observables to GPDs

Generalized Parton Distributions (GPD) are multidimensonal structure functions that encode the information about the internal structure of hadrons. Using privileged channels such as Deeply Virtual Compton Scattering (DVCS) or Timelike Compton Scattering (TCS), it is possible to make direct measurements at points where the momentum fraction of the parton equals the respective scaling variable. Double Deeply Virtual Compton Scattering (DDVCS) is a not yet measured promising channel for GPD studies as it allows to perform more general GPD measurements at independent momentum fraction and scaling variable values.

GPD values are extracted from Compton Form Factors which arise naturally in experimental observables built from different combinations of beam and target configurations. In the context of the Continuous Electron Beam Accelerator Facility (CEBAF) and the Electron Ion Collider (EIC), we report the results of an exhaustive study of the DDVCS observables built from polarized electron and positron beams directed to a polarized proton target. The study is focused on the sensitivity of the observables to the parton helicity conserving (chiral-even) proton GPDs. In particular, we focus on the consequences for GPDs measurements via DDVCS at CEBAF and EIC based on the VGG and GK19 model predictions

Orateur: Juan Sebastian Alvarado (Université Paris-Saclay - IJCLab)

DIS2024 (2).pdf

WG6: Future Experiments 1

61 ATLAS upgrades for High Luminosity LHC

While the on-going Run-3 data-taking campaign will provide twice the integrated proton-proton luminosity currently available at the LHC, most of the data expected for the full LHC physics program will only be delivered during the HL-LHC phase. For this, the LHC will undergo an ambitious upgrade program to be able to deliver an instantaneous luminosity of $7.5\times 10^{34}$ cm$^{-2}$ s$^{-1}$, allowing the collection of more than 3 ab$^{-1}$ of data at $\sqrt{s}=$13.6 (14) TeV. This unprecedented data sample will allow ATLAS to perform several precision measurements to constrain the Standard Model Theory (SM) in yet unexplored phase-spaces, in particular in the Higgs sector, a phase-space only accessible at the LHC. To benefit from such a rich data-sample it is fundamental to upgrade the detector to cope with the challenging experimental conditions that include huge levels of radiation and pile-up events. The ATLAS upgrade comprises a completely new all-silicon tracker with extended rapidity coverage that will replace the current inner tracker detector; a redesigned trigger and data acquisition system for the calorimeters and muon systems allowing the implementation
of a free-running readout system. Finally, a new subsystem called High Granularity Timing Detector will aid the track-vertex association in the forward region by incorporating timing information into the reconstructed tracks. An important ingredient, relevant to almost all measurements, is a precise determination of the delivered luminosity with systematic uncertainties below the percent level. This challenging task will be achieved by collecting the information from several detector systems using different and complementary techniques.
This presentation will describe the ongoing ATLAS detector upgrade status and the main results obtained with the prototypes, giving a synthetic, yet global, view of the whole upgrade project.

Orateur: Oleg Solovyanov

Solovyanov_DIS2024.pdf

62 Overview of the Phase-2 upgrade of CMS detector

n order to fulfill the requirements of the high luminosity and hard radiation in HL-LHC, CMS is upgrading most of the sub detectors. In this talk, an overview of the phase-2 upgrade of CMS detector will be presented.

Orateur: Arnab Purohit (CNRS, IP2I, Lyon)

ArnabPurohit_DIS2024_Final.pdf

63 The LHCb Upgrade II

The Upgrade II of the LHCb experiment is proposed for the long shutdown 4 of the LHC. The upgraded detector will operate at a maximum luminosity of 1.5×1034 cm-2 s-1, with the aim of reaching a total integrated luminosity of ∼300 fb-1 over the lifetime of the HL-LHC. The collected data will allow the full exploitation of the flavour physics capabilities of the HL-LHC, probing a wide range of physics observables with unprecedented accuracy. Among these, unique sensitivities are expected for the measurement of CKM phases and charm CP violation, as well as in rare heavy-quark decays.
To achieve this ambitious programme, the current detector performance must be maintained at the expected maximum pile-up of ∼40, and even improved in certain specific areas. To meet this challenge, it is planned to replace all existing spectrometer components to increase the granularity, reduce the amount of material in the detector and exploit the use of new technologies, including precision timing on the order of tens of picoseconds. Following the approval of a framework TDR and physics case document, detailed discussions on detector scenarios, institutional participation and funding are now underway, with the aim of starting the subdetector TDR phase immediately after.
The presentation will review the key points of the physics programme and the main options of the detector design.

Orateur: Xuhao Yuan

20240409DIS2024-yuanxuhao-v1.pdf

64 Overview of ALICE Upgrades

ALICE 3 is proposed as the next-generation experiment to address unresolved questions about the quark-gluon plasma by precise measurements of heavy-flavour probes as well as electromagnetic radiation in heavy-ion collisions in LHC Runs 5 and 6. In order to achieve the best possible pointing resolution a concept for the installation of a high-resolution vertex tracker in the beam pipe is being developed. It is surrounded by a tracker based on monolithic active CMOS pixel sensors covering roughly 8 units of pseudorapidity. To achieve the required particle identification performance, a combination of a time-of-flight system and a Ring-Imaging Cherenkov detector is foreseen. Further detectors, such as an electromagnetic calorimeter, a muon identifier, and a dedicated forward detector for ultra-soft photons, are being studied. In this presentation, we will explain the detector concept and its physics reach as well as discuss the R&D challenges.

Orateur: Rachid Guernane (LPSC)

DIS2024_RGV2.pdf

10:40 Coffee Break

65 Higgs self-coupling at the FCC-hh

The measurement of the Higgs self-coupling will be one of the benchmarks at a future hadron collider at 100 TeV, like the FCC-hh. Here we present an analysis based on the envisioned integrated luminosity of 30 ab$^{-1}$, using fast simulation samples with different systematics scenarios. The studies combine the decay channels in bb$\gamma \gamma$ and bbll+MET, to achieve a precision on $k_\lambda$ around 3 to 5 $\%$, depending on the scenario.

Orateur: Elisabetta Gallo (DESY and University of Hamburg)

DIS2024_ElisabettaGallo_FCChh_DoubleHiggs.pdf

66 Physics Potential, Accelerator Options, and Experimental Challenges of a TeV-Scale Muon-Ion Collider

A TeV muon-ion collider could be established if a high energy muon beam that is appropriately cooled and accelerated to the TeV scale is brought into collision with a high energy hadron beam at facilities such as Brookhaven National Lab, Fermilab, or CERN. Such a collider opens up a new regime for deep inelastic scattering studies at unprecedented small Bjorken-$x$ and high $Q^{2}$, as well as facilitating precision QCD and electroweak measurements and searches for beyond Standard Model physics. We revisit the potential physics program of a muon-ion collider and summarize some accelerator design options. New studies on unique key physics observables in $\mu$-p and $\mu$-nucleus will be presented. The associated experimental challenges from beam-induced backgrounds on physics signals are also explored. Initial studies of a forward muon spectrometer design applicable for a muon-ion or muon-muon collider experiment will be presented.

Orateur: Wei LI (Rice University)

MuIC_DIS24_WeiLi_04072024_v2.pdf

67 The progress of Super Tau Charm Facility in China

The proposed STCF is a symmetric electron-positron beam collider designed to provide e+e− interactions at a centerof-mass energy from 2.0 to 7.0 GeV. The peaking luminosity is expected to be 0.5×10^35 cm−2s−1. STCF is expected to deliver more than 1 ab−1 of integrated luminosity per year. The huge samples could be used to make precision measurements of the properties of XYZ particles; search for new sources of CP violation in the strange-hyperon and tau−lepton sectors; make precise independent mea-surements of the Cabibbo angle (theta)c) to test the unitarity of the CKM matrix; search for anomalous decays with sensitivities extending down to the level of SM-model expectations and so on. In this talk, the physics interests will be introduced as well as the the recent progress on the project R&D.

Orateurs: Jianbei Liu (University of Science and Technology of China (USTC), Jianbei Liu (University of Science and Technology of China)

STCF-Overview.pdf

12:40 Lunch

WG1: Structure Functions and Parton Densities 2

68 Deep-inelastic scattering with collider neutrinos at the LHC and beyond

Proton-proton collisions at the LHC generate a high-intensity collimated beam of neutrinos in the forward (beam) direction, characterised by energies of up to several TeV. The recent observation of LHC neutrinos by FASERν and SND@LHC signals that this hitherto ignored particle beam is now available for scientific inquiry. Here we quantify the impact that neutrino deep-inelastic scattering (DIS) measurements at the LHC would have on the PDFs of protons and heavy nuclei at current and future far-forward LHC neutrino experiments. We determine that up to one million electron- and muon-neutrino DIS interactions within detector acceptance can be expected by the end of the HL-LHC, covering a kinematic region overlapping with that of the Electron-Ion Collider. Including these DIS projections into global (n)PDF analyses, specifically PDF4LHC21, NNPDF4.0, and EPPS21, reveals a significant reduction of PDF uncertainties, in particular for strangeness and the up and down valence PDFs, and enables improved theoretical predictions for core processes at the HL-LHC, such as Higgs and weak gauge boson production. We also consider the possibility of extending the FCC-pp 100 TeV collider with far-forward neutrino detection capabilities.

Orateur: Juan Rojo (VU Amsterdam and Nikhef)

rojo-DIS2024-LHCneutrinos.pdf

69 Dimuon production in neutrino-nucleus collisions - the SIDIS approach

We present a next-to-leading order perturbative QCD calculation of dimuon production in neutrino-nucleus collisions. This process is vital in the determination of the strange and anti-strange quark distributions in global PDF analyses. It is usually calculated by assuming factorization to the inclusive DIS charm production cross section, with a multiplicative acceptance correction to account for the energy cut on the outgoing muons and an effective semileptonic branching ratio of charmed hadrons. We instead compute this process directly using semi-inclusive DIS cross sections and charmed-hadron fragmentation functions. As a part of this calculation, we implement the decay of the charmed hadrons to a muon by utilizing available $e^+ e^-$ data. We compare our predictions with NuTeV and CCFR data using the EPPS21, nCTEQ15HQ, and nNNPDF3.0 nuclear PDF sets, assess the uncertainties in our approach, and estimate the impact of next-to-leading power NNLO corrections. We find our results to be in good agreement with the experimental data. Additionally, we compute effective multiplicative acceptance and nuclear modification corrections. Our results for the acceptance correction show some disagreement with values used in the literature. The nuclear correction factor has a significant uncertainty arising from the nuclear PDFs.

Orateur: Sami Yrjänheikki (University of Jyväskylä)

DIS2024_yrjanheikki.pdf

70 Neutrinos at the LHC - Results from FASER

The goal of FASER, the ForwArd Search ExpeRiment, at the CERN LHC, is to investigate light, weakly-interacting particles. Aligned with the collision axis line-of-sight of the ATLAS interaction point, it is located $480$ m downstream, and covers the previously unexplored pseudorapidity range of $\eta > 8.8$. Sitting in front of the main electronic detector, the passive FASER$\nu$ neutrino detector focuses on high-energy collider neutrino interactions in the TeV regime, extending current cross-section measurements. The FASER collaboration announced in August 2023 the first direct observation of electron neutrino interactions in a particle collider experiment, using only a sub-volume of data collected so far with the FASER$\nu$ detector. Made up of alternating emulsion films and tungsten plates, it has a target mass of 1.1 tonnes. Sub-micron position resolution is achieved, allowing for all three neutrino flavours to be distinguished by their vertex topology in charged current interactions. FASER plans to run throughout the LHC Run 3, collecting $250$ fb$^{-1}$ of data. By probing forward hadron production and deep inelastic scattering of high-energy neutrinos, FASER results will provide important insights in QCD. In this presentation, recent FASER$\nu$ results, as well as the status of data taking and analysis, will be presented.

Orateur: Jeremy Atkinson

JAtkinson_DIS2024.pdf

71 First results from the SND@LHC experiment

SND@LHC started taking data at the beginning of Run 3 of the LHC. The experiment is designed to perform measurements with neutrinos produced in proton-proton collisions at the LHC in an energy range between 100 GeV and 1 TeV. It covers a previously unexplored pseudo-rapidity range of 7.2 < η < 8.4. The detector is located 480 m downstream of the ATLAS interaction point in the TI18 tunnel. The detector is composed of a hybrid system based on an 800 kg target mass of tungsten plates, interleaved with emulsion and electronic trackers, followed downstream by a calorimeter and a muon system. The configuration allows efficiently distinguishing between all three neutrino flavours, opening a unique opportunity to probe physics of heavy flavour production at the LHC in
the region that is not accessible to ATLAS, CMS and LHCb. This region is of particular interest also for future circular colliders and for predictions of very high-energy atmospheric neutrinos. The detector concept is also well suited to searching for Feebly Interacting Particles via signatures of scattering in the detector target. The experiment has published several results. This talk will focus on the experience gained from the first measurements and how this is being used to achieve the physics goals of SND@LHC.

Orateur: Onur Durhan (METU)

DIS_2024v3.pdf

15:30 Coffee Break

72 The ηc meson distribution amplitude

Distribution amplitudes are functions of non-perturbative matrix elements describing the hadronization of an initial set of quarks and gluons. They are the crossed-channel analogs of the more commonly known parton distribution functions, which describe the longitudinal momentum distribution inside a hadron. Thanks to factorization theorems, they can be used to compute the scattering amplitude of high-energy processes.
Recently, new ideas have allowed their computation using lattice QCD, which should provide us with a general, fully relativistic determination. In this seminar, we present our current $\eta_c$ meson distribution amplitude calculation on a set of $\text{N}_\text{f}=2$ CLS ensembles. Starting from the relevant matrix element in Euclidean space, we explain the method to renormalize and extrapolate to the continuum and connect to Minkowski space. After we address possible sources of systematic uncertainty, our result can be compared with similar calculations of the pion distribution amplitude to quantify the effect of the quark masses, but also with alternative methods like the non-relativistic approximation of QCD to test underlying assumptions.

Orateur: Miguel Teseo San José Pérez (Laboratoire De Physique Des 2 Infinite Irène Joliot-Curie)

main.pdf

73 Lattice QCD extraction of the $\eta_{c}$ meson's $t$-dependent parton distribution function

The formalism of short-distance factorization, conveyed through the pseudo-distribution approach, allows for the extraction of lightcone correlators from field theories formulated on Euclidean geometries. Thus, within this formalism, the extraction of parton distributions from Lattice-QCD becomes feasible. In this work we take advantage of the pseudo-distribution idea to compute, for the first time, the $t$-dependent parton distribution function of the $\eta_{c}$-meson. To this end we take advantage of the $N_{f}=2$ ensembles of gauge configurations generated by the CLS effort to compute the $\eta_{c}$-meson's pseudo-parton distribution function. Using twisted-boundary conditions we achieve its calculation on a wide Ioffe-time range, and a number of $t$-values. Finally, exploiting next-to-leading order matching relations for pseudo-distributions allows for the extraction of the looked forward $t$-dependent parton distribution functions. The $\eta_{c}$ being a heavy pseudoscalar meson, direct comparison with the corresponding results available for lighter ones -- say, pions -- allows for a pioneering unbiased estimate of the effect induced by the Higgs-mechanism on the structure of hadrons and the origin of hadron masses.

Orateur: Jose Manuel Morgado Chávez (LSN/DPhN/Irfu CEA-Saclay)

SlidesDIS2024-JMMC.pdf

WG3: Electroweak Physics and Beyond the Standard Model 2

74 Measurements of the CP structure of Higgs-boson couplings with the ATLAS experiment

While the Standard Model predicts that the Higgs boson is a CP-even scalar, CP-odd contributions
to the Higgs boson interactions with fermions and vector bosons are presently not strongly constrained. A variety of Higgs boson production processes and decays can be used to study the CP nature of the Higgs boson interactions. This talk presents the most recent CP measurements by the ATLAS experiment, based on the full dataset collected in pp collisions at 13 TeV during Run 2 of the LHC.

Orateur: Simen Hellesund

DIS2024_Measurement_of_the_CP_Structure_of_Higgs_Boson_Couplings_With_the_ATLAS_Experiment.pdf

75 Searches for rare production modes and rare decays of the Higgs boson at CMS

With the full Run2 data set of the LHC at sqrt(s)=13 TeV it is possible to search for subdominant production modes of the Higgs boson at a pp collider, like associate production of the Higgs with two b-quarks, with a c-quark, or vector boson scattering production with two associated Ws, profiting of high BR decay modes. Vice versa, by using all the possible production mechanism, searches for ultra rare decays like H->gamma+ phi/rho/K*0 can probe the Yukawa couplings to the light u,d,s quarks and the presence of BSM effects that can enhance these processes.

Orateur: Roberto Covarelli

DIS2024_higgsrare.pdf

76 Di-Higgs searches

The production of Higgs boson pairs (HH) at the LHC is the main handle for the measurement of the Higgs boson interaction with itself and is thus a fundamental test of the Standard Model theory as well as for determining the Higgs potential. The most recent results from the CMS collaboration on measurements of non-resonant HH production using different final states and their combination using the data set collected by the CMS experiment at a centre of mass energy of 13 TeV will be presented.

Orateur: Bruno Alves (LLR, Paris)

DIS24_Grenoble.pdf

77 Probing the nature of electroweak symmetry breaking with Higgs boson pairs in ATLAS

In the Standard Model, the ground state of the Higgs field is not found at zero but instead corresponds to one of the degenerate solutions minimising the Higgs potential. In turn, this spontaneous electroweak symmetry breaking provides a mechanism for the mass generation of nearly all fundamental particles. The Standard Model makes a definite prediction for the Higgs boson self-coupling and thereby the shape of the Higgs potential. Experimentally, both can be probed through the production of Higgs boson pairs (HH), a rare process that presently receives a lot of attention at the LHC. In this talk, the latest HH searches by the ATLAS experiment are reported, with emphasis on the results obtained with the full LHC Run 2 dataset at 13 TeV. Non-resonant HH search results are interpreted both in terms of sensitivity to the Standard Model and as limits on the Higgs boson self-coupling and the quartic VVHH coupling. The Higgs boson self-coupling can be also constrained by exploiting higher-order electroweak corrections to single Higgs boson production. A combined measurement of both results yields the overall highest precision, and reduces model dependence by allowing for the simultaneous determination of the single Higgs boson couplings. Results for this combined measurement are also presented. Finally, extrapolations of recent HH results towards the High Luminosity LHC upgrade are also discussed.

Orateur: Ali Shahzad

ProbingSelfCouplings_DIS2024.pdf

78 Search for b-associated production of Higgs boson in final states with leptons

One of the LHC experiment's main goals is to precisely measure the Higgs boson production mechanisms to clarify its coupling structure. In the Standard Model of particle physics, the coupling of the Higgs boson to fermions is introduced via the Yukawa interaction. Due to the low cross-section and overwhelming background processes, the Yukawa coupling to b-quarks ($y_{b}$) was measured only in the decay process and not yet in the production mechanism. This measurement aims at measuring the b-associated Higgs production (bbH) using data collected by the CMS experiment during Run 2. The study covers events where the Higgs boson is produced through the bbH channel and further decays into two tau leptons, subsequently fully leptonically ($\tau_{e}\tau_{\mu} $), semi leptonically ($\tau_{e}\tau_{h} $ , $\tau_{\mu}\tau_{h}$) , and fully hadronically ($\tau_{h}\tau_{h}$). A machine learning approach has been used to classify the events into Higgs signal classes and several background classes. First, results on the sensitivity of the bbH production channel will be shown.

Orateur: Mayam Bayat Makou

DIS.pdf

15:40 Coffee break

79 Physics of the Electroweak sector at CMS

Recent results on the EW sector from the CMS Collaboration will be presented. This includes measurements of the properties of the vector bosons and of fundamental parameters of the theory connected to the sector.

Orateur: Mario Pelliccioni

2024_DIS-2.pdf

80 Precision measurements of W and Z boson production in ATLAS

The study of single W and Z boson production at the LHC provides stringent tests of the electroweak theory and perturbative QCD. The ATLAS experiment has measured the W boson production cross section in the LHC data from 2022 at 13.6 TeV. By forming ratios with Z and ttbar production cross sections, this measurement becomes a sensitive probe of the quark and gluon content of the proton. Moreover, ATLAS has used these signatures for a range of precision measurements that are highlighted in this talk. Extraordinarily precise double-differential measurements of the Z boson in the full phase space of the decay leptons at a centre-of-mass energy of 8 TeV are discussed. The recoil of the Z-boson is sensitive to quark and gluon emissions and is used to determine the strong coupling constant in a novel approach. Measurements of the transverse momentum of the W and Z boson at 5 and 13 TeV from dedicated LHC runs with reduced instantaneous luminosity are also presented. In addition, the production rate of Z+jet events with large missing transverse momentum is used to measure the decay width of the Z boson decaying to neutrinos. Differential measurements of this topology with minimal assumptions on theoretical calculations are discussed and allow comparisons to the Standard Model as well as the interpretation in beyond-the-Standard-Model scenarios. A search for exclusive hadronic decays of the W boson to single pions, Kaons or rho-mesons in association with a photon are highlighted, and provide a test bench for the quantum chromodynamics factorization formalism. Finally, the LHC pp collision data collected by the ATLAS experiment at sqrt(s)=7 TeV is revisited to measure the W boson mass and it???s width.

Orateur: Andres Eloy Pinto Pinoargote

AP_DIS2024_ATLAS_talk_v5.pdf

81 Vector boson scattering results in CMS

Vector boson scattering is a key production process to probe the electroweak symmetry breaking of the standard model, since it involves both self-couplings of vector bosons and coupling with the Higgs boson. If the Higgs mechanism is not the sole source of electroweak symmetry breaking, the scattering amplitude deviates from the standard model prediction at high scattering energy. Moreover, deviations may be detectable even if a new physics scale is higher than the reach of direct searches. Latest measurements of production cross sections of vector boson pairs in association with two jets in proton-proton collisions at sqrt(s) = 13 TeV and 13.6 at the LHC are reported using a data set recorded by the CMS detector. Differential fiducial cross sections as functions of several quantities are also measured.

Orateur: Costanza Carrivale

DIS2024.pdf

82 Measurements of vector-boson scattering with the ATLAS experiment

Measurements of diboson production in association with two additional jets at the LHC probe interactions between electroweak vector bosons predicted by the Standard Model and test contributions from anomalous quartic gauge couplings. The ATLAS experiment has recently performed such measurements in a variety of final states, amongst them the scattering into a massive electroweak gauge boson and a photon. The scattering of massive electroweak gauge bosons is studied in leptonic final states of W boson pairs, Z boson pairs, as well as WZ pairs decays. All measurements include a comprehensive set of differential kinematic distributions. Also presented, is the measurement using semi-leptonic decays of the gauge boson pair. The measured kinematic distributions are interpreted in an Effective Field Theory approach and used to constrain dimension-8 operators.

Orateur: Antonio Giannini

DIS2024_AGiannini.pdf

83 Multiboson production and polarisation measurements with the ATLAS detector

Measurements of multiboson production at the LHC are important probes of the electroweak gauge structure of the Standard Model and can constrain anomalous gauge boson couplings. In this talk, recent measurements of diboson production by the ATLAS experiment at 13 TeV and 13.6 TeV are presented. Studies of gauge-boson polarisation and their correlation in WZ and ZZ events are also presented. In WZ events, these studies have been extended to a phase space with high transverse momentum Z bosons. Finally, measurements of triboson production are discussed, and the observation in the WWy, WZy and WWy channels are reported.

Orateur: Luka Selem

LukaSELEM_DIS2024.pdf

84 Multiboson production in CMS

This talk reviews recent measurements of multiboson production using CMS data. Inclusive and differential cross sections are measured using several kinematic observables. Constraints on new physics using the effective field theory framework are reported.

Orateur: Tarricone Cristiano

CTarricone_DIS24_MultibosonProduction_CMS-4.pdf

WG4: QCD with Heavy Flavours and Hadronic Final States 2

85 Strangeness production and polarization at LHCb

Strange hadron production is an important probe of hadronization in hadron collisions. With its precise vertex reconstruction and particle identification capabilities, the LHCb detector is ideally suited to study strangeness production. LHCb's forward geometry provides access to strange hadrons in an unexplored kinematic regime, and the SMOG system allows LHCb to study strangeness production in the highest energy fixed-target collisions ever produced in a laboratory. In addition, recent studies have linked the polarization of hyperons to the process of hadronization, and the origin of hyperon polarization from unpolarized proton-proton and proton-nucleus collisions is not yet fully understood. We present recent LHCb measurements of strangeness enhancement in charm hadron production and hyperon polarization measurements in collider and fixed-target modes. We also discuss their implications for hadronization modification in small collision systems, as well as transverse-momentum-dependent parton distributions and fragmentation functions.

Orateur: camilla de angelis

deangelis_DIS2024.pdf

86 From short to long-distance QCD with archived ALEPH e+e- at LEP1 and LEP2

Vacuum-like e+e- collisions provide outstanding opportunities to characterize the properties of Quantum chromodynamics across different energy scales. At high pT, they can be used to study the parton-shower evolution in the cleanest experimental conditions, including modern jet-substructure techniques. At low pT, measurements of two-particle long-range correlations can constrain the possible emergence of collective phenomena, which are now observed in all hadronic collisions. Measurements of energy-energy correlators in e+e- collisions allow us to connect the two energy scales. In this talk, we will present the first measurement of anti-kT jet spectra and jet substructure and the latest results of the two-particle angular correlations of charged particles, which was recently measured for the first time at LEP2 energies. The long-range near-side yield measured at high multiplicity, in particular, shows an intriguing deviation from archived MC. The most recent results on the energy-energy correlator using e+e- data will also be presented. The prospects for analogous measurements at the Electron-Ion Collider and the Future Circular Collider will also be discussed.

Orateur: Gian Michele Innocenti (MIT)

20240409_ALEPHeeDIS2024_Innocenti_Upload.pdf

87 Reconstructing, classifying and calibrating hadronic objects in ATLAS

Abstract 210:
Flavour-tagging is a critical component of the ATLAS experiment physics programme. Existing flavour tagging algorithms rely on several low-level taggers, which are a combination of physically informed algorithms and machine learning models. A novel approach presented here instead uses a single machine learning model based on reconstructed tracks, avoiding the need for low-level taggers based on secondary vertexing algorithms. This new approach reduces complexity and improves tagging performance. This model employs a transformer architecture to process information from a variable number of tracks and other objects in the jet in order to simultaneously predict the jets flavour, the partitioning of tracks into vertices, and the physical origin of each track. The inclusion of auxiliary tasks aids the models interpretability. The new approach significantly improves jet flavour identification performance compared to existing methods in both Monte-Carlo simulation and collision data. Notably, the versatility of the approach is demonstrated by its successful application in boosted Higgs tagging using large-R jets.

Abstract 246:
Hadronic object reconstruction is one of the most promising settings for cutting-edge machine learning and artificial intelligence algorithms at the LHC. In this contribution, highlights of ML/AI applications by ATLAS to particle and boosted-object identification, MET reconstruction and other tasks will be presented.

Abstract 247:
Experimental uncertainties related to hadronic object reconstruction can limit the precision of physics analyses at the LHC, and so improvements in performance have the potential to broadly increase the impact of results. Recent refinements to reconstruction and calibration procedures for ATLAS jets and MET result in reduced uncertainties, improved pileup stability and other performance gains. In this contribution, highlights of these developments will be presented.

Orateur: Pierre-Antoine Delsart (LPSC)

DIS2024_JetRecoCalibClassATLAS.pdf

88 Quarkonium fragmentation in a variable-flavor number scheme: Towards NRFF1.0

We report progress on the determination and study of quarkonium formation within the fragmentation approximation. Our analyses address the moderate and large transverse-momentum regime, where the production mechanism based on the collinear fragmentation from a single parton is expected to prevail over the short-distance emission, directly from the hard-scattering subprocess, of the constituent heavy-quark pair. We rely on Non-Relativistic-QCD (NRQCD) next-to-leading calculations for all the parton fragmentation channels to vector ($J/\psi$ and $\Upsilon$) and pseudoscalar ($\eta_c$ and $\eta_b$) quarkonia, which we take as proxies for initial-scale inputs. Thus, a complete set of variable-flavor number-scheme fragmentation functions, named NRFF1.0, are built through standard DGLAP evolution. Statistical errors are assessed via a Monte Carlo, replica-like approach that also accounts for Missing Higher-Order Uncertainties (MHOUs). The link between the NRFF1.0 approach and the MCscales one will be discussed. By starting from recent phenomenological results in the high-energy QCD sector, we trace a path towards novel studies aimed at unveiling the connection between the collinear factorization and the non-relativistic effective theory.

Orateur: Francesco Giovanni Celiberto (UAH Madrid)

talk_DIS_2024_Towards_NRFF10_2024_04_09_Celiberto.pdf

15:30 Coffee break

89 Complete one-loop study of exclusive $J/\psi$ and $\Upsilon$ photoproduction

We perform the first complete one-loop study of exclusive photoproduction of vector quarkonia off a proton, including full generalised parton distribution (GPD) evolution. We confirm the perturbative instability of the cross section at high photon-proton-collision energies at Next-to-Leading Order (NLO) using a Collinear-Factorisation (CF) framework. This issue can be tackled by a scale-fixing criterion and a `$Q_0$-subtraction' procedure to avoid the over-subtraction of the collinear singularities. In this work, we instead resolve this problem by matching the CF calculation with the one performed using High-Energy Factorisation (HEF) in the Doubly-Logarithmic Approximation (DLA). Such a DLA is a subset of the Leading-Logarithmic Approximation (LLA) of HEF which resums higher-order QCD corrections proportional to $\alpha_s^n \ln^{n-1} (\hat{s}/M^2)$ in the Regge limit $\hat{s}\gg M^2$, with $M$ being the quarkonium mass. This is strictly consistent with the NLO DGLAP evolution of GPDs. We use two models for the GPDs entering the calculation: the first one is taken from the PARTONS framework, which includes a full GPD evolution. The second one corresponds to an approximation valid at high energies in terms of Parton Distributions Functions (PDFs) via the Shuvaev transform, in which only PDFs are evolved. We find that our approach alleviates the instability observed for the NLO calculation in the CF framework at high energies. We further compare our results for the two GPD models and assess the reliability of the Shuvaev transform as a means to probe the small $x$ gluon PDFs via the exclusive photoproduction of vector quarkonia.

Orateur: Dr Saad Nabeebaccus (IJCLab)

nabeebaccus-jpsi-photoproduction-DIS-2024.pdf

90 One-loop QCD corrections to inclusive production of $J/\psi$ and $\Upsilon$ in $e^+e^-$ annihilation

The impact of Next-to-Leading Order (NLO) QCD corrections to the differential distributions of $J/\psi$ and $\Upsilon$ mesons produced inclusively in $\gamma\gamma$ collisions is revisited for the kinematical conditions of LEPII DELPHI, the Circular Electron-Positron Collider (CEPC) and the Future Circular (Lepton) Collider (FCC-ee). We take into account all sizeable LO in $v^2$ contributions in NRQCD factorization: 1) pure QED process $\gamma + \gamma \rightarrow J/\psi({}^3S^{[1]}_1) + \gamma$ at NLO in $\alpha_s$, 2) single-resolved photon contribution at NLO in $\alpha_s$, 3) $\gamma+\gamma\to J/\psi + c\bar{c}$ in the LO in $\alpha_s$ and 4) $\gamma+\gamma\to J/\psi + ggg$ in the LO in $\alpha_s$.

Orateur: Maxim Nefedov (IJClab, Orsay)

Nefedov_Jpsi.pdf

WG5: Spin and 3D Structure 2

91 An overview of nucleon spin and 3D structure at STAR

Spin, a fundamental and subtle concept in nuclear physics, is deeply rooted in the symmetries and structure of space-time. The primary goal of the Spin Physics Program at the STAR experiment is to use spin as a probe to unravel the internal structure and the QCD dynamics of nucleons with unprecedented precision. This is made possible by the unique capability of RHIC to provide both longitudinally and transversely polarized hadronic collisions at various energies.

Longitudinally polarized data from STAR have, for the first time, provided evidence for a positive gluon polarization at partonic momentum fraction $x$>0.05, with ongoing efforts aimed at further constraining gluon helicity. Measurements of the reconstructed $W$ bosons in longitudinally polarized collisions probe asymmetric anti-quark helicity distributions in the proton sea. Transversely polarized data open new territory in studying the 3D structure of the proton. The $W$/$Z$ bosons serve as probes for the sea-quark Sivers function and contribute to tests of the predicted sign-change phenomena. The tilt of the dijet opening angle provides direct access to the first Mellin momentum of the Sivers function. Novel measurements of the azimuthal distributions of identified hadrons in jets and spin-dependent dihadron correlations directly probe the collinear quark transversity in the proton, with the former coupled to the transverse momentum dependent Collins fragmentation function and the latter to the dihadron interference fragmentation function.

This presentation will provide an overview of recent results on nucleon spin and the 3D structure of the proton from the STAR experiment.

Orateur: Xiaoxuan Chu (BNL)

DIS2024_xchu.pdf

92 Probing gluon and strange quark helicity distribution in the proton at STAR

Unraveling the proton spin composition, comprising intrinsic spins and angular momenta of quarks and gluons, stands as one of the most fundamental and challenging questions in QCD. Tremendous progress has been made since the first surprising result by the EMC experiment in the late 1980s, significantly contributing to our understanding of this question. However, the helicity distributions of strange quarks and anti-quarks inside the proton are still not well constrained by the experimental data.
Measurement of the longitudinal double spin asymmetry, $A_{LL}$, of $\Lambda$, $\overline{\Lambda}$ and $K_S^0$ in the longitudinally polarized proton-proton collisions may shed light on the strange quark and anti-quark helicity distributions. In addition, the $A_{LL}$ of the inclusive jets tagged with a $\pi^+/\pi^-$ carrying high jet momentum fraction, $z$, in proton-proton collisions can provide further constraints on the gluon helicity distribution in the proton.

In this talk, we will present the preliminary results of the $A_{LL}$ for $\Lambda$, $\overline{\Lambda}$ and $K_S^0$, and the inclusive jets tagged with a high-$z$ $\pi^{\pm}$. These results are based on the longitudinally polarized proton-proton collisions at $\sqrt{s}=200$ $\rm{GeV}$ collected by the STAR experiment with an integrated luminosity of about 52 $\rm{pb^{-1}}$.

Orateur: Yi Yu

DIS2024_YiYu.pdf

93 The forward $\eta$ meson cross section and prospects for the forward $\eta$ meson $A_N$ at PHENIX

The spin physics program of the PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) has a number of recent and ongoing analyses exploring the spin structure of the proton. Leveraging the unique capability of RHIC to collide polarized proton beams, transverse single spin asymmetry ($A_N$) measurements at PHENIX are performed on a variety of final states. These analyses are typically accompanied by a cross section measurement, which itself often offers additional insight into unpolarized proton structure.

In this presentation, I will first discuss results from a recent PHENIX measurement of the forward $\eta$ meson cross section. Cross sections of hadron final states access the unpolarized fragmentation functions and, at PHENIX kinematics, are particularly sensitive to gluon fragmentation. The only available set of $\eta$ meson fragmentation functions, the AESSS fragmentation functions, are still relatively unconstrained, especially compared to their $\pi^{0}$ counterparts. This measurement is planned to eventually serve as an input in an updated global analysis of $\eta$ meson fragmentation functions.

Next, I will present the status of a PHENIX measurement of the forward $\eta$ meson $A_N$. This measurement provides a direct probe of the twist-3 quark-gluon-quark correlation function, and is related to the Sivers TMD PDF describing the correlation between the transverse spin of the proton and the transverse momentum of its constituent parton. This new measurement will complement a forward $\eta$ meson $A_N$ from an earlier PHENIX dataset, and will be used both to validate the previous results and to improve the statistical precision of the measurement.

Orateur: Devon Loomis (University of Michigan)

DIS2024_Loomis.pdf

94 Measurement of $\Lambda$ hyperon spin-spin correlations in p+p collisions by the STAR experiment

About 50 years ago, it was discovered that $\Lambda$ hyperons are produced polarized in collisions of unpolarized protons on beryllium. Since then, the $\Lambda$ polarization has been observed in various collision systems, including $e^+$+$e^-$ collisions. Majority of current results indicate the importance of final state effects, such as hadronization or fragmentation, in polarization of the $\Lambda$ hyperons. A recently proposed technique for the investigation of the $\Lambda$ hyperon polarization is a measurement of $\Lambda\bar{\Lambda}$, $\Lambda\Lambda$, and $\bar{\Lambda}\bar{\Lambda}$ spin-spin correlations. This technique is expected to help understand if the $\Lambda$ polarization has any contribution from the early stage of the $p$+$p$ collisions, e.g., from initial state parton spin correlation, or if it is exclusively a final state effect.

In this presentation, we present the preliminary results of the $\Lambda\Lambda$, $\bar{\Lambda}\bar{\Lambda}$, and $\Lambda\bar{\Lambda}$ spin-spin correlations in $p$+$p$ collisions at $\sqrt{s} = 200\,\textrm{GeV}$ collected by the STAR experiment in 2012. The $\Lambda$ and $\bar{\Lambda}$ candidates are reconstructed at mid-rapidity ($|y| < 1$) with transverse momentum in range of $0.5 < p_\mathrm{T} < 5.0\,\mathrm{GeV}/c$. This measurement will provide additional insight into the importance of the initial state effects for the $\Lambda$ hyperon polarization.

Orateur: Jan Vanek (Brookhaven National Laboratory)

DIS_2024_Vanek_final.pdf

15:30 Coffee Break

95 Towards NNPDFpol2.0

I review the recent efforts in the NNPDF collaboration towards a new extraction of polarized parton distributions functions (pPDF) which will be highly relevant for the upcoming Electron-Ion-Collider (EIC) experiments. This includes a recent study on heavy quark effects in polarized DIS, where we apply the FONLL prescription for the first time in a polarized setup and demonstrate the non-negligible impact specifically on the polarized gluon distribution. We show some preliminary results of the new pPDF release NNPDFpol2.0 based on the latest machine learning framework (as established in NNPDF4.0) and the new theory prediction pipeline. Finally, we report on a community effort to fully establish the evolution of pPDFs at NNLO accuracy.

Orateur: Felix Hekhorn (University of Jyväskylä)

talk.pdf

96 Towards helicity-dependent parton distribution functions at next-to-next-to-leading order accuracy

We present a new determination of the helicity-dependent parton distribution functions (PDFs) of the proton from a set of longitudinally polarised inclusive deep-inelastic scattering and semi-inclusive deep-inelastic scattering data. The determination includes, for the first time, next-to-next-to-leading order QCD corrections to both processes, and is carried out in a framework that combines a neural-network parametrisation of PDFs with a Monte Carlo representation of their uncertainties. We discuss the quality of the determination, in particular its dependence on higher-order corrections, on theoretical constraints, and on the choice of data set.

Orateur: Amedeo Chiefa (The University of Edinburgh)

DIS_2024_MAP_4_3.pdf

97 Single- and double-unresolved limits of polarised matrix elements

Calculations at NNLO in QCD require an analytic understanding of the infrared singular structure involving up to two unresolved partons, which was achieved up to now only for unpolarized matrix elements. We derive the full set of splitting amplitudes arising in longitudinally polarised tree-level QCD matrix elements at NNLO in the Larin $\gamma_5$ scheme. They are extracted from DIS-like processes and verified in matrix elements of higher multiplicity. Our results will enable the calculation of NNLO corrections to longitudinal spin asymmetries in polarized collider processes.

Orateur: Markus Löchner (University of Zurich)

talk.pdf

98 Angular momentum distribution for a quark dressed with a gluon

We investigate the different decompositions of the angular momentum in QCD for a relativistic spin $1/2$ composite state, namely a quark dressed with a gluon. We use light-front Hamiltonian perturbation theory, and in the light-front gauge, use the two-component framework by eliminating the constrained degrees of freedom. We also investigate the different decompositions of the angular momentum at the level of two-dimensional densities in the front form, including the effect of the so-called potential term. In this work, we consider the contribution coming from the quark part of the energy-momentum tensor. We contrast the different decompositions and also compare them with other calculations in the literature. We also present the gravitational form factor related to the antisymmetric part of the energy-momentum tensor.

Orateur: Prof. Asmita Mukherjee (Indian Institute of Technology Bombay)

DIS2024.pdf

99 Determining spin dependent gluon distributions from top quark pair production at the LHC

Inclusive top quark pair production at the LHC proceeds primarily via gluon fusion. Decays of the polarized top pairs through various particle and jet channels have strong angular dependences reflecting the top and anti-top polarizations that produce a variety of correlations among the decay products - particles and jets. Those correlations are determined by the spin dependent gluon distributions from the unpolarized colliding protons. Combinations of the gluon distributions, either polarized or unpolarized, can be accessed experimentally through angular dependences of top decay products, as will be shown, along with preliminary predictions from a model of gluon distributions.

Orateur: Gary Goldstein (Tufts University)

100 Matching between TMD and twist-3 factorizations in the transversely polarized hyperon production

The origin of the large single transverse-spin asymmetries(SSAs) has been a long-standing problem since they were first observed in the pion production and the transversely polarized hyperon production about a half century ago. We currently know two successful pQCD based frameworks in the description of the SSA. One of them is transverse-momentum-dependent(TMD) factorization which is valid when a produced hadron has small transverse momentum compared to the hard scale of a process. The other framework is the twist-3 effect in the collinear factorization which is valid when the transverse momentum is large so that it can be regarded as the hard scale. Although these two frameworks seemingly describe different origins of the SSA, some theoretical work showed that they give the consistent result to the SSA in the intermediate region where both frameworks are valid. This sort of the consistency is important for giving a unified picture to the origin of the SSA. Our group recently has completed the leading-order cross section for the twist-3 fragmentation contributions in the polarized hyperon production in SIDIS. In this talk, we will show our result on the matching between TMD and the twist-3 for this contribution.

Orateur: Shinsuke Yoshida (South China Normal University)

DIS2024_yoshida1.pdf

101 Probing the polarized fragmentation function in unpolarized collisions

The longitudinal spin transfer of the fragmentation function, $G_{1L}$, represents the probability density of producing longitudinally polarized hadrons from longitudinally polarized quarks or circularly polarized gluons. It thus was usually measured in polarized reactions or high-energy collisions where weak interaction dominates. In our work, we propose the dihadron polarization correlation as a novel probe of this quantity. Such an observable does not require the fragmenting partons to be polarized and therefore can be measured in the currently available experimental facilities, such as Belle, RHIC, Tevatron, and the LHC.

We make quantitative predictions for these experiments. In light of the data already harvested, the experimental investigation of this observable provides more opportunity for the quantitative study of the longitudinal spin transfer. In particular, the measurements in unpolarized $pp$ or $AA$ collisions can significantly constrain the fragmentation function of a circularly polarized gluon.

References

[1] Probing the longitudinal spin transfer via dihadron polarization correlations in unpolarized ${e^{+}e^{-}}$ and ${pp}$ collisions, H.C. Zhang, S.Y. Wei, Phys.Lett.B839, 137821 (2023).

[2] Correlations of dihadron polarization in central, peripheral and ultraperipheral heavy-ion collisions, X. Li, Z.X. Chen, S. Cao, S.Y. Wei, Phys.Rev.D 109, 014035 (2024).

Orateur: Shu-Yi Wei (Shandong University)

DIS2024.pdf

102 Longitudinal spin transfer of semi-inclusive $\Lambda$ production in deep inelastic scattering

We study the longitudinal spin transfer of $\Lambda$-hyperon production in semi-inclusive deep inelastic scattering with both current and target fragmentation mechanisms. For existing fixed-target experiments, such as JLab, COMPASS and HERMES, the events from the current region and those from the target fragmentation region are not clearly separated. However the study of target fragmentation is relatively limited, we propose a new approach to directly compute the target fracture functions based on the spectator diquark model, which can quantify the contributions of target fragmentation well. We find that the contribution from the target fragmentation can significantly suppress the spin transfer to the $\Lambda$ in the medium-energy SIDIS process. The predictions are consistent with existing experimental data from COMPASS, HERMES, and CLAS12, and will soon be examined at high energy levels in upcoming experiments.

Orateur: Xiaoyan Zhao (Shandong University)

DIS2024.pdf

WG6: Future Experiments 2

103 ALICE Forward Calorimeter upgrade (FoCal): Physics program and performance

The FoCal is a high-granularity forward calorimeter to be installed as an ALICE upgrade subsystem during the LHC Long Shutdown 3 and take data during the LHC Run 4. It will cover a pseudorapidity interval of $3.4 < \eta < 5.8$, allowing to explore QCD at unprecedented low Bjorken-$x$ of down to $\approx 10^{-6}$ -- a regime where non-linear QCD dynamics are expected to be sizable. It consists of a compact silicon-tungsten sampling electromagnetic calorimeter (FoCal-E) with pad and pixel longitudinal and transverse segmented readout layers to achieve high spatial resolution for discriminating between isolated photons and decay photon pairs. Its hadronic component (FoCal-H) is constructed from copper capillary tubes filled with scintillator fibers and used for isolation energy measurement and jets.

The FoCal detector extends the ALICE physics program with the capability, unique at the LHC, to investigate gluon Parton Distribution Functions (PDFs) in the low-$x$ regime. This not only enables the study of non-linear QCD effects such as gluon saturation, but also allows to provide experimental constrains for (nuclear) PDFs in a region of phasespace where experimental data is scarce. The detector design allows carrying out these explorations using a multitude of probes, including direct photons, jets, as well as photo-production of vector mesons such as the J/$\psi$ in proton-Pb and Pb-Pb ultra-peripheral collisions. In addition, correlations of different probes can be studied, including gamma-jet, jet--jet and $\pi^0$--$\pi^{0}$ correlations.

In this presentation, we give an overview of the small-x physics program of the FoCal detector, as well as an overview of the expected performance of the detector for various observables. The latter is quantified using recent experimental results of ever-improving prototypes of the detector, which were operated at the Test Beam facilities of CERN in the years 2021--2023. Furthermore, simulation studies are presented, which showcase the robustness of the detector design and its physics potential.

Orateur: Laura Huhta (University of Jyvaskyla)

DISFoCal-4.pdf

104 Future Physics with CMS detector at HL-LHC

The High-Luminosity Large Hadron Collider (HL-LHC) is expected to deliver an integrated luminosity of up to 3000 fb-1. The very high instantaneous luminosity will lead to about 200 proton-proton collisions per bunch crossing (“pileup”) superimposed on each event of interest, providing extremely challenging experimental conditions. Prospects for Standard Model (SM) measurements and searches beyond the SM are discussed.

Orateurs: Jyothsna Rani Komaragiri (Indian Inst. of Technol. Madras), Jyothsna Rani Komaragiri (Indian Institute of Science (IISc))

DIS2024-Jyothsna-FuturePhysics.pdf

105 ATLAS ITk Pixel Detector Overview

In the high-luminosity era of the Large Hadron Collider, the instantaneous luminosity is expected to reach unprecedented values, resulting in up to 200 proton-proton interactions in a typical bunch crossing. To cope with the resulting increase in occupancy, bandwidth and radiation damage, the ATLAS Inner Detector will be replaced by an all-silicon system, the Inner Tracker (ITk). The innermost part of the ITk will consist of a pixel detector, with an active area of about 13 m^2. To deal with the changing requirements in terms of radiation hardness, power dissipation and production yield, several silicon sensor technologies equipped with novel ASICs connecting by bump-bonding technique will be employed in the five barrel and endcap layers. As a timeline, it is facing to pre-production of components, sensor, building modules, mechanical structures and services.
This contribution presents the status of the ITk-pixel project focusing on the lessons learned and the biggest challenges towards production, from mechanics structures to sensors, and it will summarize the latest results on closest-to-real demonstrators built using module, electric and cooling services prototypes.

Orateur: Ali Skaf (University of Gottingen)

ITk_Pixel_preview_DIS2024_ASkaf.pdf

106 Expected performance of the ATLAS ITk detector for HL-LHC

The increased instantaneous luminosity levels expected to be delivered by the High-Luminosity LHC (HL-LHC) will present new challenges to High-Energy Physics experiments, both in terms of detector technologies and software capabilities. The current ATLAS inner detector will be unable to cope with an average number of 200 simultaneous proton-proton interactions resulting from HL-LHC collisions. As such, the ATLAS collaboration is carrying out an upgrade campaign, known as Phase-II upgrade, that foresees the installation of a new all-silicon tracking detector, the Inner Tracker (ITk), designed for the expected occupancy and fluence of charged particles. The new detector will provide a wider pseudorapidity coverage and an increased granularity. In this contribution the expected performance of the ITk detector will be presented, with emphasis on the improvements on track reconstruction resulting from the new detector design.

Orateur: Yassine El Ghazali (University of Science and Technology of China (CN))

ElGhazali_DIS2024.pdf

107 The ATLAS ITk Strip Detector System for the Phase-II LHC Upgrade

ATLAS is currently preparing for the HL-LHC upgrade, with an all-silicon Inner Tracker (ITk) that will replace the current Inner Detector. The ITk will feature a pixel detector surrounded by a strip detector, with the strip system consisting of 4 barrel layers and 6 endcap disks. After completion of final design reviews in key areas, such as Sensors, Modules, Front-End electronics and ASICs, a large scale prototyping program has been completed in all areas successfully. We present an overview of the Strip System, and highlight the final design choices of sensors, module designs and ASICs. We will summarize results achieved during prototyping and the current status of production and pre- production on various detector components, with an emphasis on QA and QC procedures.

Orateur: Elizaveta Sitnikova

DIS 2024 for pdf.pdf

15:40 Coffee Break

108 Upgrade of ATLAS Hadronic Tile Calorimeter for the High Luminosity LHC

The Tile Calorimeter (TileCal) is the hadronic calorimeter covering the central region of the ATLAS experiment. The High-Luminosity phase of LHC, delivering five times the LHC nominal instantaneous luminosity, is expected to start in 2029. TileCal will require new electronics to meet the requirements of a 1 MHz trigger, higher ambient radiation, and to ensure better performance under high pile-up conditions. Both the on- and off-detector TileCal electronics will be replaced during the shutdown of 2026-2028. Approximately 10%of the PMTs, those reading out the most exposed cells, will be replaced. PMT signals from every TileCal cell will be digitized and sent directly to the back-end electronics, where the signals are reconstructed, stored, and sent to the first level of trigger at a rate of 40MHz. This will provide better precision of the calorimeter signals used by the trigger system and will allow the development of more complex trigger algorithms. The modular front-end electronics feature radiation-tolerant components and redundant design to minimize single points of failure. The timing, control and communication interface with the off detector electronics is implemented with modern Field Programmable Gate Arrays (FPGAs) and high speed fibre optic links running up to 9.6 Gb/s. The TileCal upgrade program has included extensive R&D and test beam studies. A Demonstrator module equipped with the new electronics but with reverse compatibility with the existing readout system was inserted in ATLAS in August 2019 for testing in actual detector conditions. The status of the various components and the results of test-beam campaigns with the electronics prototypes will be discussed.

Orateur: Oleg Solovyanov

Solovyanov_DIS2024_TileUpgrade.pdf

109 Technical challenges and performance of the new ATLAS LAr Calorimeter Trigger

To cope with the increase of the LHC instantaneous luminosity, new trigger readout electronics were installed on the ATLAS Liquid Argon Calorimeters.

On the detector, 124 new electronic boards digitise at high speed 10 times more signals than the legacy system. Downstream, large FPGAs are processing up to 20 Tbps of data to compute the deposited energies. Moreover, a new control and monitoring infrastructure has been developed.

This contribution will present the challenges of the commissioning, the first steps in operation, and the milestones still to be completed towards the full operation of both the legacy and the new trigger readout paths for the LHC Run-3.

Orateur: Emilien Chapon (CEA Saclay)

chapon_DIS2024.pdf

110 Machine Learning for Real-Time Processing of ATLAS Liquid Argon Calorimeter Signals with FPGAs

The Phase-II Upgrade of the LHC will increase its instantaneous
luminosity by a factor of 7 leading to the HL-LHC era.
At the HL-LHC, the number of proton-proton collisions in one bunch
crossing, pileup, increases significantly, putting stringent
requirements on the LHC detectors electronics and real-time data
processing capabilities.

The ATLAS LAr calorimeter measures the energy of particles produced
in LHC collisions. It also feeds the ATLAS trigger to identify
interesting events. To enhance the ATLAS physics discovery potential
at HL-LHC, an excellent energy resolution and an accurate time
detection is crucial.

The computation of the deposited energy is performed using
electronic boards based on FPGAs. Currently this computation is done
using optimal filtering algorithms that are adapted to situations with
limited pileup.
With the increased luminosity and pileup,
the performance of the optimal filter algorithms decreases.

The off-detector electronic boards for the LAr Phase-II Upgrade
will use the next generation of INTEL FPGAs with increased processing
power and memory.
This will allow the use on these boards of more complex algorithms.
We developed several neural networks (NNs) with
significant performance improvements with respect to the optimal
filtering algorithms.

Five NN algorithms will be presented. The improvement of the energy
resolution and the accuracy of the deposited time compared to the legacy
filter algorithms will be discussed.
The implementation of these networks in firmware will be shown.

Orateur: Johann Christoph Voigt (TU Dresden)

2024_04_ML_ATLAS_LAr_Johann_Voigt.pdf

111 Development of the ATLAS Liquid Argon Calorimeter Readout Electronics for the HL-LHC

A new proton-proton collisions era at 14 TeV will start around 2029 with the
HL-LHC. To withstand the higher radiation doses and the harsher data taking
expected at HL-LHC, the ATLAS Liquid Argon (LAr) Calorimeter readout
electronics needed an upgrade.

The LAr electronic upgrade is composed of four main components.

1: New front-end boards which will allow to amplify, shape and digitise
the calorimeter’s ionisation signal on two gains over a dynamic range
of 16 bits and 11-bit precision.
Custom preamplifiers and shapers were developed using CMOS
technologies.
Two concurrent preamp-shaper ASICs were designed. “ALFE” was selected
to be the best. Results of the latest version of this ASIC is
presented.
ALso, results on a new developed ADC chip called “COLUTA”, the production and
the ongoing integration tests are shown.

2: New calibration boards which will allow the precise calibration of all
182468 channels of the calorimeter over a 16-bit dynamic range.
A non-linearity of one per mille and non-uniformity of
0.25% shall be achieved.
The latest versions of the 2 ASICs that passed recent PDR are presented.

3: New ATCA-compliant signal processing boards (“LASP”) which will receive
the detector data at 40 MHz where FPGAs connected through lpGBT
links will perform energy and time reconstruction.
The latest development status of the board and the firmware
are shown. For the first time machine-learning techniques
are considered for these FPGAs.

4: A new timing and control system, “LATS”, will synchronise with
the aforementioned components. Its current design status is shown.

Orateur: Elena Mazzeo (INFN)

240408_LArPhaseIIUpgrade_DIS2024_v6.pdf

112 Upgraded Lucid and Zero Degree Calorimeter Detectors for ATLAS at the High Luminosity LHC

The ATLAS pp physics program at the High Luminosity LHC (HL-LHC) requires precision luminosity measurement with systematic control better than 1% during operation with up to 200 simultaneous interactions per crossing. ATLAS will feature several luminosity detectors but at least one of them must be both calibratable in the van der Meer scans at low luminosity and able to maintain accuracy at the highest luminosities. LUCID-3, the upgrade of the present ATLAS luminometer (LUCID-2), will fulfill these requirements.

The LHC heavy ion community has mapped out a large range of physics measurements at the HL-LHC that will push forward our understanding of both QCD, QED and even electroweak physics that requires zero-degree calorimeters for both triggering and offline event classification. The modified geometry of the HL-LHC requires new detectors that are both thinner and much more radiation hard. A joint project between ATLAS and CMS is underway to construct calorimeters for the HL-LHC that would be used by both experiments.

This talk will present the designs for the LUCID-3 and HL-LHC ZDC detectors and discuss specific aspects of the HL-LHC geometry and radiation environment that affect the design of the detectors. For LUCID-3, two options are being studied: the first is based on photomultipliers (PMT) as for LUCID-2, while the second is based on optical fibers. Both solutions aim at reducing the acceptance of the detector to avoid the saturation of the luminosity algorithms. Results obtained from prototype detector installed in ATLAS in Run-3 are discussed. ZDCs at the LHC are typically tungsten-sampling calorimeters using quartz Cherenkov radiators. The upgraded ZDCs will use very radiation hard fused silica rods that resulted from an R&D program involving the ZDC teams, the LHC BRAN group, and private companies. The resulting design of the calorimeters and expectations for their performance will be discussed.

Orateur: Antonio Sbrizzi

DIS240409sbrizziFinal.pdf

WG2: Small-x, Diffraction and Vector Mesons 2

113 Higgs production at NLL accuracy in the BFKL approach

Orateur: Francesco Giovanni Celiberto (UAH Madrid)

talk_DIS_2024_Higgs_NLL-HyF_Celiberto.pdf

114 Pole decomposition of BFKL eigenvalue

Orateur: Alex Prygarin (Ariel University)

dis24_prygarin.pdf

115 Small-x resummation of photon impact factors and virtual photon scattering at high energies

Orateur: Dimitri Colferai (University of Florence)

colferai.pdf

15:30 Coffee break

116 Coherent vector meson photoproduction and polarization in heavy-ion collisions with nuclear overlap in ALICE

Orateur: Afnan Shatat (Universite Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France)

SHATAT_DIS_2024_indico.pdf

117 Energy dependence of coherent J$/\psi$ production off lead with ALICE

Orateurs: Guillermo Contreras (Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Prague, Czech Republic), Guillermo Contreras (Czech Technical University in Prague)

DIS2024_JGC.pdf

118 Odderon at the EIC from exclusive $\chi_c$ production

Orateur: Sanjin Benic (University of Zagreb)

benic_dis2024.pdf

119 Impact factor for forward eta-c meson production at NLO

Orateur: Maxim Nefedov (IJClab, Orsay)

Nefedov_DIS-2024.pdf

17:20 Intermezzo: break for unwinding

120 Odderon Mechanism for Transverse Single Spin Asymmetry in pp and pA Collisions

Orateur: Eric Andreas Vivoda (Physics department, Faculty of Science, University of Zagreb)

Vivoda_DIS2024.pdf

121 Global analysis of polarized DIS & SIDIS data with improved small-x helicity evolution

Orateur: Yossathorn Tawabutr (University of Jyväskylä)

DIS2024_Tawabutr.pdf

122 Investigations on η’ photoproduction off near-free neutron at Graal

Orateur: Antonio Riggio (INFN, University of Messina)

Investigations on etaprime photoproduction off near neutron at GRAAL.pdf

WG1: Joint WG1+WG4

123 Recent progress in the calculation of the N3LO splitting functions

The four-loop DGLAP splitting functions, which govern the scale evolution of the Parton Distribution Functions (PDFs), are of the missing ingredients to push the frontier of QCD calculations to N3LO accuracy, as required to match the experimental precision at the LHC and at the forthcoming EIC. In this talk, I will report on the recent progress in the determination of the splitting functions from the direct calculation of a fixed number of moments of these quantities. This approach allow to control the evolution of the PDFs to percent-level precision over the relevant range of momentum fraction x.

Orateur: Giulio Falcioni (University of Torino and University of Zürich)

falcioni.pdf

124 A general mass variable flavor number scheme for Z boson associated with a heavy quark production at hadron colliders

The general mass variable flavor number (GMVFN) scheme S-ACOT-MPS will
be discussed for proton-proton collisions. The impact of heavy-flavor
contributions within this factorization scheme will be shown for the production of a $Z$ boson in association with a charm/bottom quark in pQCD. An amended version of the QCD factorization formula for proton-proton collisions will be discussed as well as the role of $Z+c/b$ production at the LHC in constraining heavy-flavor PDFs. Phenomenological applications will be presented.

Orateur: MARCO GUZZI (Kennesaw State University)

MGuzzi-SACOT-MPS-DIS2024.pdf

125 Measurement of jet production in deep inelastic scattering and NNLO determination of the strong coupling at ZEUS

A new measurement of inclusive-jet cross sections in the Breit frame in neutral current deep inelastic scattering using the ZEUS detector at the HERA collider is presented. The data were taken in the years 2004–2007 at a centre-of-mass energy of 318 GeV and correspond to an integrated luminosity of 347 pb$^{-1}$. The jets were reconstructed using the $k_T$-algorithm in the Breit reference frame. They have been measured as a function of the squared momentum transfer, $Q^2$ , and the transverse momentum of the jets in the Breit frame, $p_{\perp,Breit}$. The measured jet cross sections are compared to previous measurements and to perturbative QCD predictions. The measurement has been used in a next-to-next-to-leading-order QCD analysis to perform a simultaneous determination of parton distribution functions of the proton and the strong coupling, resulting in a value of $\alpha_s(M_Z^2) = 0.1142 \pm 0.0017~$(experimental/fit)$~^{+0.0006}_{-0.0007}~$(model/prameterisation) $~^{+0.0006}_{-0.0004}~$(scale), whose accuracy is improved compared to similar measurements. In addition, the running of the strong coupling is demonstrated using data obtained at different scales.

Orateur: Florian Lorkowski (University of Zürich)

InclusiveJets.pdf

126 Measurement of the 1-jettiness event shape observable in deep inelastic electron-proton scattering at HER

The H1 Collaboration reports the first measurement of the 1-jettiness event shape observable $\tau_{1}^{b}$ in neutral-current deep-inelastic electron-proton scattering. The analysis is based on data recorded in 2003-2007 by the H1 detector at the HERA collider for ep collisions at $\sqrt{s}=319$ GeV, with integrated luminosity of 351.1 pb$^{-1}$. The observable $\tau_{1}^{b}$ is equivalent to a thrust observable defined in the Breit frame. The triple differential cross section is presented as a function of $\tau_{1}^{b}$, event virtuality $Q^2$, and inelasticity y, in the kinematic region $Q^2 > 150$ GeV$^2$. The data are compared to predictions from Monte Carlo event generators and NNLO pQCD calculations. These comparisons reveal sensitivity of this observable to QCD parton shower and resummation effects, the magnitude of the strong coupling constant, and proton parton distribution functions, as well as the modeling of hadronization and fragmentation.

Orateur: Johannes Hessler (<PI Munich)

DIS24_jettiness_hessler.pdf

127 Energy Energy correlators in DIS

The energy-energy correlator(EEC) is an event shape observable that probes the angular correlations of energy depositions in detectors at high-energy collider facilities. It has been investigated extensively in the context of precision QCD. In this talk, I will present our recent works on the energy-energy correlator in DIS. In the back-to-back limit, the observable we propose is sensitive to the universal transverse momentum-dependent parton distribution functions and fragmentation functions. In the collinear limit, a new definition of nuclear energy-energy correlator is defined. We revisit the NEEC definition that is Bjorken x weighted EEC and perform the study in the full phase space region.

Orateur: Haitao Li (Shandong University, Jinan, China)

EEC_DIS.pdf

128 Simultaneous Determination of Fragmentation Functions and Test on Momentum Sum Rule

We perform a simultaneous global analysis of hadron fragmentation functions (FFs) to various charged hadrons at next-to-leading order in QCD. The world data set includes results from electron-positron single-inclusive annihilation, semi-inclusive deep inelastic scattering, as well as proton-proton collisions including jet fragmentation measurements which lead to strong constraints on the gluon fragmentations. By carefully selecting hadron kinematics to ensure the validity of QCD factorization and the convergence of perturbative calculations, we achieve a satisfying best fit with $\chi^2$/d.o.f=0.90, in the simultaneous extraction of FFs for light charged hadrons($\pi^{\pm}$, $K^{\pm}$ and $p/\bar p$). The total momentum of u,d quarks and gluon carried by light charged hadrons have been determined precisely.

Orateur: Jun Gao (Shanghai Jiaotong University)

DIS2024_JG.pdf

mercredi 10 avril

WG1: Structure Functions and Parton Densitites 3

129 PDF uncertainties: a critical examination

In this talk I will re-examine the definition of PDF errors within the MSHT framework. This is a key issue in light of LHC high precision requirements that must be addressed if we are to provide accurate as well as precise PDF determinations. I will in particular examine the role of the tolerance and the question of parameterisation flexibility and bias, and comment on the implications of this on LHC phenomenology.

Orateur: Lucian Harland-Lang (University College London)

lhl_closure_DIS24.pdf

130 A critical assessment of uncertainty propagation methodologies in PDF fitting

This study presents a novel methodology for estimating uncertainty intervals in fits of Parton Distribution Functions (PDFs). By combining toy examples and fitting real-world PDFs, we critically evaluate the robustness of the Monte-Carlo (MC) replica method and the Hessian method in estimating credible intervals for PDFs. Our findings reveal that the methodologies typically used in PDF fits fail to replicate Bayesian interval estimates in some cases, mainly due to their inability to handle terms that are nonlinear as a function of the fitting parameters. We conclude by suggesting potential directions for further research to address these limitations and explore alternative approaches for constructing robust parameter interval estimates in PDF analyses.

Orateur: Mark N. Costantini (University of Cambridge)

dis2024_grenoble_costantini.pdf

131 A study of systematic uncertainties within the MSHT PDF framework.

As experimental data is becoming more precise, understanding the impact of the uncertainties in the errors, especially the systematic errors, is increasingly becoming a significant focus of PDF groups. In this talk we will explain how the error on errors can be modelled and how this framework can be applied to both uncorrelated and correlated systematic errors, and discuss the potential relationship to the PDF tolerance. We then investigate the PDF fits for ATLAS W,Z Data and the ATLAS 7 TeV Jet data with relation to this technique.

Orateur: Matthew Reader (UCL)

DIS_Talk_2024-latest.pdf

132 Bayesian Inference and Gaussian Processes for PDF determination

We discuss a Bayesian methodology for the solution of the inverse problem underlying the determination of parton distribution functions (PDFs). In our approach, Gaussian Processes (GPs) are used to model the PDF prior, while Bayes’ theorem is used in order to determine the posterior distribution of the PDFs given a set of data. We discuss the general formalism, the Bayesian inference at the level of both parameters and hyperpa- rameters, and the simplifications which occur when the observable entering the analysis is linear in the PDF. We benchmark the new methodology in two simple examples for the determination of a single PDF flavor from a set of Deep Inelastic Scattering (DIS) data and from a set of equal-time correlators computed using lattice QCD. We discuss our results, showing how the proposed methodology allows for a well-defined statistical interpretation of the different sources of errors entering the PDF uncertainty, and how results can be validated a posteriori.

Orateur: Tommaso Giani (Nikhef)

dis24_giani.pdf

133 A Markov chain Monte Carlo determination of Proton PDF uncertainties at NNLO

The current scientific standard in PDF uncertainty estimation relies either on repeated fits over artificially generated data to arrive at Monte Carlo samples of best fits or on the Hessian method, which uses a quadratic expansion of the figure of merit, the $\chi^2$-function. Markov chain Monte Carlo methods allows one to access the uncertainties of PDFs without making use of quadratic approximations in a statistically sound procedure while at the same time preserving the correspondence between the sample and $\chi^2$-value.
Rooted in Baysian statistics the $\chi^2$-function is repeatedly sampled to obtain a set of PDFs that serves as a representation of the statistical distribution of the PDFs in their function space. After removing the dependence between the samples (the so-called autocorrelation) the set can be used to propagate the uncertainties to physical observables.
The final result is an independent procedure to obtain PDF uncertainties that can be confronted by the state-of-the-art in order to ultimately arrive at a better understanding of the proton's structure

Orateur: Peter Risse (University of Münster)

Risse_DIS24_grenoble.pdf

10:30 Coffee Break

134 nCTEQ global analysis of nuclear PDFs

We discuss the preliminary results of our new global nuclear PDF analysis that combines a number of our previous improvements into one consistent framework with updates to the underlying theoretical treatment as well as the addition of new available data. In particular, the new global analysis will be the first to include neutrino DIS scattering data together with JLab high-$x$ DIS data and new LHC p-Pb data from $W/Z$ as well as heavy quark production. These additions will allow to improve the data-driven description of nuclear PDFs in new regions such as the gluon for very low-$x$ or the nuclear strange quark PDF.

Orateur: Tomas Jezo (ITP, University of Muenster)

TJezo.pdf

135 Estimating nPDF Uncertainties via Markov Chain Monte Carlo Methods

Nuclear Parton Distribution Functions (nPDFs) are crucial for understanding nuclear structure and for providing predictions for heavy-ion collisions. nPDFs have been determined via ‘global QCD analyses’, which is a statistical approach based on performing a fit of nPDF-dependent theoretical predictions to the relevant experimental data. One of the crucial aspects of nPDF determination is the estimation of its uncertainties. Typically, the Hessian method is used to propagate experimental uncertainties into predictions for collisions of nuclei. However, due to the nature of nPDF fits (such as limited data constraints, non-gaussianity, and possible multiple minima), this method does not always provide reliable results. Here, we will show a case study for an alternative approach where nPDF uncertainties are estimated using a more advanced statistical method based on the Markov Chain Monte Carlo (MCMC) approach. MCMC methods address nPDF challenges by generating a sequence of random samples from a probability distribution of nPDF parameters and effectively exploring the entire parameter space. This approach allows for a more comprehensive analysis of uncertainties, particularly in complex scenarios such as nPDF fits.

Orateur: Mlle Nasim Derakhshanian (Institute of nuclear physics PAN)

DIS2024_N.Derakhshanian.pdf

136 Revisiting ``target mass corrections'' in lepton-nucleus deeply inelastic scattering

Deeply inelastic scattering (DIS) of a high-energy leptons ($\ell$ or $\nu$) off hadronic targets remains an incredibly powerful probe of both hadronic substructure and leptonic couplings to matter. As current and near-future experiments will investigate DIS kinematics at large Bjorken $x$ and small momentum transfers to unrivaled precision on a variety of nuclei, it remains crucial that our theoretical understanding of this regime remains firm. Along these lines, we have revisit so-called target mass corrections (TMCs) to nuclear structure functions, which account for the fact that the masses of nuclei are not guaranteed to be small compared to momentum transfers in DIS.

In this talk, we start with a qualitative picture, intended for a broad audience, and move onto more technical details of the work, e.g., cross sections, ratios of cross section, etc. We show that nuclear parton distribution functions can be expressed directly in terms of partonic degrees of freedom (quarks and gluons), and that intermediate pictures of "bound nucleons" are not necessary. If time allows, we also show that nuclear TMCs can be expressed in a way that is universal for all nuclei and readily implemented in numerical codes.

Orateur: Richard Ruiz (IFJ PAN)

rruiz_DIS24_nTMCs.pdf

137 Systematic uncertainty of off-shell corrections and higher-twist contribution in DIS at large x

We study the systematic uncertainty and possible biases introduced by theoretical assumptions needed to include DIS data at large x in a global QCD analysis. In particular, working in the CTEQ-JLab framework, we focus on different implementations of higher-twist corrections to the nucleon structure functions, and of off-shell deformations of PDF in deuteron targets, and how their interplay impacts the extraction of the d-quark PDF and the calculation of the neutron structure function at large x. The full inclusive DIS data set from JLab will be leveraged to further constrain the studied corrections.

Orateur: Matteo Cerutti (Hampton University and Jefferson Lab)

Cerutti_DIS2024_adobe.pdf

Cerutti_DIS2024_preview.pdf

138 On the interplay of nuclear and higher-twist corrections in nuclear DIS at large x

We study nuclear DIS basing on a microscopic model [1], which addresses a number of nuclear corrections arising from energy-momentum spectrum of bound nucleons, off-shell modification of bound nucleon structure functions, corrections from meson-exchange currents, focusing on the region of large Brorken x and the light nuclei with two and three bound nucleons, for which the energy-momentum distributions are known with a good accuracy. The off-shell correction responsible for the modifications of the partonic structure in bound protons and neutrons is constrained from a global QCD analysis together with the PDFs in the proton. In the analysis including the deuterium (2H), tritium (3H) and helium-3 (3He) data we constrain the individual off-shell effects for the proton and neutron and study its interplay with the higher-twist terms in the structure functions. We found a negligible proton-neutron asymmetry in the relative off-shell effect and demonstrate an excellent description of nuclear data with a single isoscalar off-shell function [2-4]. The inclusion of the new data from MARATHON experiment on the ratios of nuclear cross sections 3He/2H and 3H/2H allows to increase accuracy of the determination of the universal nucleon off-shell function which drives nuclear corrections for all nuclei. We also provide our predictions on the neutron/proton ratio of structure functions F2n/F2p and on the d and u quark distributions in the proton and in the 3H and 3He nuclei.

References

[1] S.A. Kulagin and R. Petti, Nucl. Phys. A765 (2006) 126.
[2] S.I. Alekhin, S.A. Kulagin, R.Petti, Phys. Rev. D96 (2017) 054005.
[3] S.I. Alekhin, S.A. Kulagin, R.Petti, Phys. Rev. D105 (2022) 114037.
[4] S.I. Alekhin, S.A. Kulagin, R.Petti, Phys. Rev. D107 (2023) L051506.

Orateur: Roberto Petti

DIS24-Petti.pdf

WG4: QCD with Heavy Flavours and Hadronic Final States 3

139 Precision calculations for groomed event shapes at HERA

The possibility to reanalyse data taken by the HERA experiments offers the chance to study modern QCD jet and event-shape observables in deep-inelastic scattering. In this talk I will present resummed and matched predictions for the event shapes 1-jettinesss [1] and invariant mass including the effect of grooming the hadronic final state using the soft-drop technique. Non-perturbative corrections from hadronisation are taken into account through parton-to-hadron level transfer matrices extracted from dedicated Monte Carlo simulations with Sherpa, including uncertainties extracted from replica tunes to data from the HERA experiments. I will present results corresponding to the H1 setup that is equivalent to preliminary experimental analyses of those observables.

[1] Knobbe, Reichelt, Schumann JHEP 09 (2023) 194

Orateur: Daniel Reichelt (Durham University)

DIS_2024_DReichelt.pdf

140 First measurement of groomed event shape observables in deep-inelastic electron-proton scattering at HERA

The H1 Collaboration at HERA reports the first measurement of groomed event shapes in deep inelastic e−p and e+p scattering (DIS) at $\sqrt{s} = 319$ GeV, using data recorded between 2003 and 2007 with an integrated luminosity of $351.1\pm 9.5$ pb$^{−1}$. Event shapes in DIS collisions provide incisive probes of perturbative and non-perturbative QCD, and recently developed grooming techniques investigate similar physics in jet measurements of hadronic collisions. This paper presents the first application of grooming to DIS data. The analysis is carried out in the Breit frame, utilizing the novel Centauro jet clustering algorithm that is designed for DIS event topologies. Events are required to have squared momentum–transfer $Q^2 > 150$ GeV$^2$ and inelasticity $0.2 < y < 0.7$. We report measurements of the production cross section of groomed event 1-jettiness and groomed invariant jet mass for several choices of grooming parameter. The measurements are compared to Monte Carlo models and to analytic calculations based on Soft Collinear Effective Theory (SCET).

Orateur: Henry Klest (Argonne National Laboratory)

Klest DIS24 H1.pdf

Klest DIS24 H1.pptx

141 High-purity gluon jet showers from secondary Lund jet planes

The Lund jet plane is a jet substructure tool introduced to understand the radiation pattern of jets by organizing hadrons into a hierarchical tree of emissions using the Cambridge/Aachen clustering algorithm. The primary LJP, the first triangular leaf of Lund diagrams, is well understood analytically, and measurements at the LHC show how it can be used to constrain parton showers and hadronization models in a factorized way. We propose to extend the exploration of the Lund jet tree by turning to its secondary leaves, the secondary Lund jet planes, for further QCD measurements. If the respective primary Lund emission is chosen judiciously, such that it corresponds to the first branching in the jet shower, one can constrain the modeling of gluon-initiated jet showers independently of the quark/gluon jet fraction in the jet sample. We illustrate how one could use such a sample of gluon-rich jet radiation for an extraction of $\alpha_\mathrm{S}(m_\mathrm{Z})$ using a Lund-based multiplicity observable recently introduced in the literature.

Orateur: Cristian Baldenegro (Sapienza Università di Roma (IT))

DIS2024.pdf

142 Measurements of jet substructure using the CMS detector

The internal structure of jets allows us to bridge our description and understanding of short-distance physics and color confinement. In this talk, we discuss recent measurements of jet substructure performed using data collected by the CMS experiment. Measurements of various jet substructure observables, with and without jet grooming, are presented. The measurements are corrected for detector effects and are compared to predictions based on state-of-the-art analytical calculations and Monte Carlo event generators.

Orateur: Jelena Mijuskovic

DIS2024_JetSubstructure_JMijuskovic.pdf

143 Jet substructure measurements and precision measurements of multijet production with the ATLAS experiment

Abstract 244:
Jets, the collimated streams of hadrons resulting from the fragmentation of highly energetic quarks and gluons, are some of the most commonly observed radiation patterns in hadron collider experiments. The distribution of quantum chromodynamic (QCD) radiation within jets is determined by complex processes, the production of showers of quarks and gluons and their subsequent recombination into hadrons. In this talk, several recent measurements of the jet substructure from the ATLAS experiment are presented. The measurements utilise either multijet events or jets produced in the decay of W bosons and the fragmentation of b-quarks in top pair production, using the reconstructed charged particles inside the jet. Presented are measurements of non-perturbative track functions, as well as differential cross-section of Lund sub-jet multiplicities and measurements of the Lund Jet Plane in top quark pair production. Finally, the substructure of top-quark jets, using top quarks reconstructed with the anti-kt algorithm is highlighted. The results are compared to a large variety of parton shower models and tunes.

Abstract 249:
The production of jets at hadron colliders provides stringent tests of perturbative QCD. The latest measurements by the ATLAS experiment are presented in this talk, using multijet events produced in the proton-proton collision data at sqrt(s) = 13 TeV delivered by the LHC. Jet cross-section ratios between inclusive bins of jet multiplicity are measured differentially in variables that are sensitive to either the energy-scale or angular distribution of hadronic energy flow in the final state. Several improvements to the jet energy scale uncertainties are described, which result in significant improvements of the overall ATLAS jet energy scale uncertainty. The measurements are compared to state-of-the-art NLO and NNLO predictions. A measurement of new event-shape jet observables defined in terms of reference geometries with cylindrical and circular symmetries using the energy mover???s distance is highlighted.

Orateur: Zdenek Hubacek

prez_dis_090424_v2.pdf

10:30 Coffee break

144 Precision boson-jet azimuthal decorrelation at hadron colliders

In this talk, we present our results for the azimuthal decorrelation of a vector boson and jet in proton-proton collisions. We show that using a recoil-free jet definition reduces the sensitivity to contamination from soft radiation on the measurement and simplifies our theoretical calculation by eliminating complications associated with non-global logarithms. Specifically, we consider the $p_T^n$ recombination scheme, as well as the $n\to \infty$ limit, known as the winner-take-all scheme. These jet definitions also significantly simplify the calculation for a track-based measurement, which is preferred due to its superior angular resolution. We present a detailed discussion of the factorization in Soft-Collinear Effective Theory as well as resummation in the back-to-back limit up to next-to-next-to-leading logarithms. Whether the potential glauber contributions spoil our factorization formalism will also be commented on. We conclude with a detailed phenomenological study, finding an enhanced matching correction for high jet $p_T$ due to the electroweak collinear enhancement of a boson emission off di-jets. We also compare with the Pythia event generator, showing the robustness of our observable to effects of hadronization and the underlying event.

Orateur: Bin Wu (Universidade de Santiago de Compostela)

DIS2024_Wu.pdf

145 Theoretical predictions for $t{\bar t}W$ cross sections at approximate N$^3$LO

We present theoretical calculations of higher-order QCD and electroweak corrections for the associated production of a top-antitop quark pair and a $W$ boson ($t{\bar t}W$ production) at LHC energies. We show predictions for cross sections at approximate N$^3$LO (aN$^3$LO) which include second-order and third-order soft-gluon corrections added to the exact NLO QCD+electroweak result. We compare our results to recent measurements from the LHC, and we find that our predictions provide improved agreement with the data. We also calculate the top-quark transverse momentum and rapidity distributions in $t{\bar t}W$ production. We find significant enhancements from the higher-order corrections to the total and differential cross sections for this process.

Orateur: Nikolaos Kidonakis (Kennesaw State University)

Kidonakis-talk.pdf

146 Linear power corrections to top quark production processes

We discuss the linear power corrections in $\Lambda_{\text{QCD}}$ to top quark production processes in hadron collisions using renormalon calculus. We show how such non-perturbative corrections can be obtained using the Low-Burnett-Kroll theorem, which provides the first subleading term to the expansion of the real-emission amplitudes around the soft limit. We demonstrate that there are no linear power corrections to the total cross sections provided that these cross sections are expressed in terms of a short-distance top quark mass. We also derive a universal formula for the linear power corrections to generic observables that involve the top-quark momentum.

Orateur: Melih OZCELIK (IJCLab)

DIS2024_OZCELIK.pdf

147 Top-Bottom Interference Contribution to Fully-Inclusive Higgs Production

We evaluate the top-bottom interference contribution to the fully-inclusive Higgs production cross section at next-to-next-to-leading order in QCD. Although bottom-quark-mass effects are power-suppressed, the accuracy of state-of-the-art theory predictions makes an exact determination of this effect indispensable. With this result, we address one of the leading theory uncertainties of the cross section.

Orateur: Tom Schellenberger (RWTH Aachen)

DIS2024.pdf

148 Measurements of $\gamma$ from tree-level decays at LHCb

The only source of matter-antimatter asymmetry in the Standard Model (SM) of particle physics occur through the complex phase of the Cabibbo-Kobayashi-Maskawa (CKM) quark mixing matrix. This complex phase is the origin of the violation of both the charge (C) and parity (P) symmetries. Violation of CP symmetry can be studied by measuring the angles of the CKM unitarity triangle. One of these angles, $\gamma$, can be measured using only tree-level processes; a method that, assuming new physics is not present in tree-level decays, has negligible theoretical uncertainty. Disagreement between such direct measurements of $\gamma$ and the value inferred from global CKM fits, assuming the validity of the SM, would indicate new physics beyond the SM. The precise determination of $\gamma$ is one of the most important goals of LHCb. $\gamma$ measurements have been obtained from several $B^+$, $B^0$ and $B_0^s$ decays using both time-independent and time-dependent measurements. These single measurements are combined to achieve the best experimental accuracy on $\gamma$. The proposed presentation will review the most recent single measurements of $\gamma$ and present the current status of the LHCb $\gamma$ combination, obtained with Run1 and Run2 data, followed by prospects for Run3 and beyond

Orateur: Alessandro Bertolin

DIS2024-WG4-Wen-bertolin.pdf

WG3: Electroweak Physics and Beyond the Standard Model 3

149 top+X (ttX, tX) measurements ATLAS

The high center-of-mass energy of proton-proton collisions and the large available datasets at the CERN Large Hadron Collider allow to study rare processes of the Standard Model with unprecedented precision. Measurements of rare SM processes provide new tests of the SM predictions with the potential to unveil discrepancies with the SM predictions or provide important input for the improvement of theoretical calculations. In this contribution, total and differential measurements of top-quark production in association with a photon, Z or W boson are shown using data taken with the ATLAS experiment at a center-of-mass-energy of 13 TeV. These measurements provide important bounds on the electroweak couplings of the top quark and constrain backgrounds that are important in searches for Higgs production and for new phenomena beyond the SM.

Orateur: Harriet Watson

HWatson_topX_DIS_10042024.pdf

150 Highlights on top quark properties, mass and cross-section measurements with the ATLAS detector

The top-quark mass is one of the key fundamental parameters of the Standard Model that must be determined experimentally. Its value has an important effect on many precision measurements and tests of the Standard Model. The Tevatron and LHC experiments have developed an extensive program to determine the top quark mass using a variety of methods. In this contribution, the top quark mass measurements by the ATLAS experiment are reviewed. These include measurements in two broad categories, the direct measurements, where the mass is determined from a comparison with Monte Carlo templates, and determinations that compare differential cross-section measurements to first-principle calculations. In addition, new results on top-quark properties are shown. This includes the first observation of quantum entanglement in top-quark pair events and a test of lepton-flavour universality in emu final states.

Orateur: Luis Monsonis Romero

LuisMR_DIS2024.pdf

151 Recent highlights of top quark production from CMS

High-precision measurements of top quark cross-sections are crucial to advance our understanding of perturbative and soft QCD and provide a deeper understanding of the partons inside the proton. In this talk, recent highlights of top quark cross-section measurements at CMS ranging from 5 TeV up to 13.6 TeV will be presented. Moreover, new results of differential cross-section measurements in challenging phase space and of rare associated top-quark production will be discussed.

Orateur: Jeremy Andrea

JAndrea.pdf

152 Searches for BSM in top final states in ATLAS

The LHC is a top factory and run 2 has delivered billions of top quarks to the experiments. In this contribution, the results are presented of searches by the ATLAS experiment for Charge Lepton Flavour Violation (cLFV), lepton flavour universality, Heavy-neutrinos, and rare flavour-changing neutral current interactions of the top quark (FCNC). FCNC analyses combine search regions targeted at top quark decays t -> qX with regions aimed at single top quark production pp -> tX, where X is either a gluon, photon, Z-boson or a Higgs boson. The large data set, together with advanced analysis techniques, allow to improve the sensitivity very significantly and competitive bounds on the equivalent BR(t->qH) are presented.

Orateur: Gabriel Gomes

Gomes_DIS2024.pdf

153 Search for rare and BSM top-quark production and decays

Millions of top quarks already produced at LHC TeV are ideal for searching for rare top-quark decays. Besides flavor-changing neutral currents that are highly suppressed in the Standard Model, baryon and lepton number conservation can be probed in top quark events. In this talk, recent searches for rare and beyond the Standard Model top-quark production and decay with significantly increased sensitivity will be discussed. Several of the measurements are the first of their kind.

Orateur: Olga Bessidskaia Bylund

rare_bsm_top_cms.pdf

10:40 Coffee break

154 ATLAS Latest Dark Matter Searches

The presence of a non-baryonic Dark Matter (DM) component in the Universe is inferred from the observation of its gravitational interaction. If Dark Matter interacts weakly with the Standard Model (SM) it could be produced at the LHC. The ATLAS experiment has developed a broad search program for DM candidates, including resonance searches for the mediator which would couple DM to the SM, searches with large missing transverse momentum produced in association with other particles (light and heavy quarks, photons, Z and H bosons) called mono-X searches and searches where the Higgs boson provides a portal to Dark Matter, leading to invisible Higgs decays. The results of recent searches on 13 TeV pp data, their interplay and interpretation will be presented.

Orateur: Nikolai Fomin

dis_atlasdm.pdf

155 ATLAS Searches for Lepto-Quarks and Vectorlike-Quarks

The Standard Model of Particle Physics explains many natural phenomena yet remains incomplete. Leptoquarks (LQs) are hypothetical particles predicted to mediate interactions between quarks and leptons, bridging the gap between the two fundamental classes of particles. Vectorlike quarks (VLQs) lie at the heart of many extensions seeking to address the Hierarchy Problem, as they can naturally cancel the mass divergence for the Higgs boson. This talk will present the new results from LQ and VLQ searches with the ATLAS detector using the Run-2 dataset.

Orateur: Tomoya Iizawa

Tomoya.pdf

156 Searches for dark matter with CMS

Determination of the nature of dark matter is one of the most fundamental problems of particle physics and cosmology. This talk presents recent searches for dark matter particles rom the CMS experiment at the Large Hadron Collider. The results are based on proton-proton collisions recorded at sqrt(s) = 13 TeV with the CMS detector.

Orateur: Jesus Manuel Vizan Garcia (Universidad de Cantabria / Instituto de Fisica de Cantabria)

DIS24_Vizan_final.pdf

157 Recent highlights of supersymmetry searches from CMS

Recent highlights of supersymmetry searches from the CMS experiment are presented. These searches use proton-proton collision data with luminosity up to 138 fb-1 recorded by the CMS detector at center of mass energy 13 TeV during the LHC Run 2.

Orateur: Pablo Matorras Cuevas

DIS24SUSYSearches_10042024.pdf

158 Searches for Higgs-like and other Heavy Resonances in ATLAS

Many new physics models predict the existence of resonances decaying into two bosons (W, Z, photon, or Higgs bosons) making these important signatures in the search for new physics. Searches for Vy, VV, and VH resonances have been performed in various final states. In some of these searches, jet substructure techniques are used to disentangle the hadronic decay products in highly boosted configurations. This talk summarises recent ATLAS searches with Run 2 data collected at the LHC and explains the experimental methods used, including vector- and Higgs-boson-tagging techniques.

Orateur: Jackson Barr

2024-04-10-DIS.pdf

WG5: Spin and 3D Structure 3

159 Overview of Nucleon Spin and 3-d structure program at JLab

An overview of the JLab program on nucleon spin and 3-d structure will be given. Highlights from recent experimental results will be presented with measurements focusing in the high-x (valence quark) region and/or in the low to intermediate Q2 region. Future perspective will be discussed.

Orateur: Dr Jian-ping Chen (Jefferson Lab)

Chen-DIS2024.pdf

160 Dependence of Charged Pion Production on Transverse Momentum from Semi-Inclusive Deep Inelastic Electron Scattering from $^1$H and $^2$H

Measurements of semi-inclusive deep inelastic scattering (SIDIS) are an important constraint on the description of the parton structure functions. Both the intrinsic $k_\perp$ of the quarks as well as the $p_\perp$ dependence of the hadronization process affect the dependence of the SIDIS cross section on transverse momentum ($P_T$). Experimental determination of the transverse momentum dependence of the SIDIS cross section constrains models of transverse momentum dependent parton distributions and fragmentation functions, and allows the development of a fully 3D momentum picture of the nucleon. Precise measurements of the transverse momentum dependent cross sections for electroproduction of charged pions have been performed using liquid hydrogen and deuterium targets impinged on by 11 GeV electrons, with the scattered electron and produced hadron observed by the two magnetic spectrometers in Jefferson Lab Hall C. Data with invariant photon mass $Q^2$ greater than 2 GeV$^2$ and hadronic recoil energy W greater than 2 GeV were collected to find cross sections at $x_{BJ}$ ranges of 0.3-0.5 and fractional energy $z$ of 0.3 to 1.0 with $P_T$ from 0 to 0.7 GeV/c; the coverage in hadron azimuthal angle $\phi_h$ is generally from 0 to 360º for $P_T$ less than 0.4 GeV/c. The statistical precision of the charged pion data is on the order of 1-2%, with comparable systematic uncertainties expected, allowing the determination of the fully differential cross section in $z$, $P_T$, and $\phi_h$. Preliminary results of charged pion SIDIS from $^1$H and $^2$H will be presented, along with results of a 4-parameter phenomenological fit.

Orateur: Edward Kinney (University of Colorado)

Kinney-DIS2024-NB.pdf

161 Precision three-dimensional imaging of nuclei using recoil-free jets

We explore the azimuthal angle decorrelation of lepton-jet pairs in e-p and e-A collisions as a means for precision measurements of the three-dimensional structure of bound and free nucleons. Utilizing soft-collinear effective theory, we perform the first-ever resummation of this process in e-p collisions at NNLL accuracy using a recoil-free jet axis. Our results are validated against Pythia simulations. In e-A collisions, we address the complex interplay between three characteristic length scales: the medium length L, the mean free path of the energetic parton in the medium λ, and the hadronization length Lh. We demonstrate that in the thin-dilute limit, where L ≪ Lh and L ∼ λ, this process can serve as a robust probe of the three-dimensional structure for bound nucleons. We conclude by offering predictions for future experiments at the Electron-Ion Collider within this limit.

Orateur: Dingyu Shao (Fudan University)

shao_DIS23.pdf

162 DVCS on Polarized Nucleons with the CLAS12 experiment at Jefferson Lab

Deeply Virtual Compton Scattering is the most direct channel to access
Generalized Partons Distributions (GPDs) and understand more about the 3D
structure of the nucleon, the origin of its spin and the forces at play
within it. The complete extraction of GPDs requires the use of polarized
electron beams and polarized nucleon targets in DVCS measurements.

The first polarized target experiment of the CLAS12 program at JLab took
place last year, scattering 10.6 GeV electrons on longitudinally polarized protons and neutrons in hydrogen and deuterium targets. It is of high interest for DVCS measurements as it will allow to measure the target-spin and double-spin asymmetries for the first time on neutrons. These results will allow to extract neutron Compton Form Factors over a large phase-space and access the H and E GPDs for the neutron. Combining results on the proton and the neutron will allow for the flavor decomposition of GPDs. A preliminary asymmetry extraction has been performed and will be presented, with highlights on the analysis tools that have been specifically developed to work with a polarized nuclear target.

Orateur: Noémie Pilleux (IJCLab, Université Paris Saclay)

DIS2024 - DVCS on Polarized Nucleons with the CLAS12 experiment at Jefferson Lab-1.pdf

10:30 Coffee Break

163 New physical processes for extracting generalized parton distributions with a better sensitivity to partonic structure

Generalized parton distributions (GPDs) encode important non-perturbative information of hadron structures including the tomographic parton images. We introduce a type of exclusive processes for a better study of GPDs, which we refer to as single diffractive hard exclusive processes (SDHEPs), and give a general argument for their factorization into GPDs. We advocate a two-stage framework for picturing SDHEPs, which not only gives a clear view of factorization properties but also provides a unified description of the kinematics including various polarization asymmetries. We demonstrate that the SDHEP is not only sufficiently generic to cover all known processes but also well motivated for searching for new processes for extracting GPDs. Importantly, we also examine the sensitivity of the SDHEP to the parton momentum fraction $x$-dependence of GPDs, and demonstrate it quantitatively with two specific processes that can be readily measured at J-PARC/AMBER using a pion beam and at JLab using a photon beam, respectively. Both processes are capable of providing enhanced sensitivity to the $x$-dependence, overcoming the problem of shadow GPDs, and disentangling different types of GPDs with various spin asymmetries.

Orateurs: Prof. Jianwei Qiu (Jefferson Lab), Zhite Yu (Jefferson Lab)

DIS_WG5_Qiu_Yu.pdf

164 Double DVCS including kinematic twist-4 corrections

Generalized parton distributions (GPDs) are off-forward matrix elements of quark and gluon operators that work as a window to the total angular momentum of partons and their transverse imaging (nucleon tomography). To access GPDs one needs to look into exclusive processes, out of which double deeply virtual Compton scattering (DDVCS) is a promising mechanism to measure GPDs outside the lines $x=\pm\xi$ at leading order (which is a restriction in DVCS and TCS cases). Here, $x$ represents the average longitudinal momentum carried by an active parton, while $\xi$ is the skewness parameter.

These aforementioned exclusive processes are usually studied in a kinematic regime known as the Björken limit, where the photon virtualities are much larger than the hadron mass $M$, and the kick to the hadron measured by the Mandelstam's variable $t$. This is not enough for the purposes of precise GPD extraction or nucleon tomography, for which measurements in a sizable range of $t$ are required. Deviation with respect to the Björken limit induces the kinematic higher-twist corrections which enter the amplitudes with powers of $|t|/Q^2$ and $M^2/Q^2$, where $Q^2$ denotes the scale of process (sum of photon virtualities in the case of DDVCS).

In this talk, I present novel calculations of DDVCS off a (pseudo-)scalar target up to first order power corrections (twist-4). These results are important for measuring DDVCS, DVCS and TCS through the Sullivan process and off helium-4 target at the future Electron-Ion Collider (EIC) and JLab experiments.

Orateur: Victor Martinez (National Centre for Nuclear Research (NCBJ))

DIS2024_slides_2024_VMF.pdf

165 Breakdown of collinear factorisation in the photoproduction of a $\pi^0 \gamma$ pair with large invariant mass

In this talk, I will discuss our work in 2311.09146, regarding the breakdown of collinear factorisation in the exclusive photoproduction of a $\pi^0 \gamma$ pair. Such a process is sensitive to both quark and gluon GPD channels. In the latter case, the amplitude fails to factorise, due to the presence of a Glauber pinch, which has the same power counting as the collinear pinch. The Glauber pinch that occurs here is peculiar, since the mechanism that produces it involves two loop integrals. I will demonstrate this explicitly, and will further show the Ward identities do not lead to the power suppression of the Glauber pinch. This is corroborated by an explicit calculation of the gluon GPD channel to $\pi^0 \gamma$ pair photoproduction, which leads to a divergent amplitude already at leading twist-2 and at leading order in $\alpha_s$. Such collinear factorisation breaking effects also occur in similar processes, such as the crossed channel of $\pi^0 N \to \gamma\gamma N$ scattering for the same reason. On the other hand, it should be stressed that for processes where the gluon GPD channel is forbidden, which correspond to the case where the outgoing meson is a charged pion or a rho meson, collinear factorisation still applies without any issues.

Orateur: Dr Saad Nabeebaccus (IJCLab)

nabeebaccus-factorisation-breaking-DIS-2024.pdf

166 Generalized parton distributions through universal moment parameterization: the gluonic sector with deeply virtual J/ψ production at next-to-leading order

We present a further step toward a global extraction of generalized parton distributions (GPDs) in the Generalized parton distributions through universal moment parameterization (GUMP) framework. We include HERA measurements of Deeply Virtual Meson Production (DVMP) in order to study gluon GPDs at non-zero skewness using the same moment parameterization ansatz as the previous global fit which included lattice QCD calculations and experimental measurements. We concentrate our study on the production of $J/\psi$ mesons, where the main contribution to the amplitudes comes from the gluon GPDs, and we combine collinear factorization to next to leading order in the expansion in $\alpha_s$ with the leading power corrections in $M_{J/\psi}^2/Q^2$ from non-relativistic QCD.

Orateur: M Gabriel Santiago (SURA Center for Nuclear Femtography)

DIS_2024_gpds_santiago.pdf

167 Off-Forward parton structure in Ioffe time space

In this talk I will describe a Lattice QCD calculation of parton structure from off-forward matrix elements. Similar to DVCS cross sections, these matrix elements are convolutions of Generalized Parton Distributions (GPDs), or equivalently Double Distributions (DDs). In our methodology, the computational cost of many different momenta combinations can be ameliorated allowing for a plethera of data, crucial for obtaining accurate 3D pictures of the nucleon. We utilize the Lorentz invariant pseudo-GPD framework to handle the many frames simultaneously. Within this picture and as shown in our data, the well known GPD features of polynomiality naturally arise in Ioffe time space, the Fourier conjugate of the momentum fraction x. We are also able to extract Gravitational Form Factors and other moments of the GPDs.

Orateur: Savvas Zafeiropoulos (LPC-CNRS)

DIS2024_Zafeiropoulos.pdf

WG6: Future Experiments 3

168 A New Era of Discovery: The 2023 Long Range Plan for Nuclear Science

The 2023 Long Range Plan for Nuclear Science, titled "A New Era of Discovery," outlines the significant opportunities and key challenges for our community over the next decade. It is the culmination of the July 2022 charge from the Department of Energy Office of Science and the National Science Foundation to the Nuclear Science Advisory Committee to "conduct a new study of the opportunities and priorities for United States nuclear physics and recommend a long range plan (LRP) that will provide a framework for coordinated advancement of the Nation's nuclear science research program over the next decade." The 2023 LRP, and associated white papers, are available at https://nuclearsciencefuture.org. This presentation will review the LRP process and discuss some of its highlights, such as the four recommendations, current and future facilities, cross-cutting opportunities, and the importance of the nuclear science workforce.

Orateur: Ian Cloet (Argonne National Laboratory)

169 SoLID: A Detector at the Luminosity Frontier.

The Solenoidal Large Intensity Device (SoLID) is a large acceptance detector capable of operating at the luminosity frontier. It was proposed to fully exploit the potential of the continuous electron beam accelerator facility (CEBAF) 12 GeV energy upgrade at Jefferson Lab. The pillars of its scientific program consist of a series of Semi-Inclusive Deep Inelastic Scattering (SIDIS) experiments to explore the transverse-momentum dependent parton distributions of the nucleon (TMDs) at a new level of precision and provide quark momentum tomography of the nucleon internal structure, a parity-violating deep inelastic scattering (PVDIS) experiment to explore physics beyond the standard model, and a near-threshold $J/\psi$ photo- and electro-production experiment to determine the gluonic gravitational form factors and address the origin of the nucleon mass. I will discuss the need and virtues of SoLID and its potential impact on the science program of hadronic physics and physics beyond the standard model.

Orateur: Dr Zein-Eddine Meziani (Argonne National Laboratory)

DIS2024-SoLID-Meziani-final.pdf

170 The CLAS12 luminosity upgrade and future physics opportunities

The CEBAF Large Acceptance Spectrometer, CLAS12, in Hall B at Jefferson Lab runs experiments with a multitude of unpolarized and polarized targets using electron beams of 2 GeV to 11 GeV energies at close to the design luminosity of $L=10^{35}$ cm${-2}$ sec$^{-1}$. Since its commissioning in early 2018, CLAS12 has successfully executed a physics program that covers a broad range of topics in nuclear physics.

The necessity of high statistics data in multidimensional kinematic phase space became evident with the analysis and publication of the first cutting-edge results on nucleon and nuclear structure. To address this demand, we plan to upgrade CLAS12 to run at higher luminosities. The first stage of the upgrade, currently in progress, aims at improving the tracking efficiency in the forward region of polar angles, with a near-term goal of reaching a production luminosity of $L=2\times 10^{35}$ cm${-2}$ sec$^{-1}$. This upgrade will fulfill the requirements of the already approved experiments. The second stage of the upgrade aims at reaching luminosities of $L>10^{37}$ cm${-2}$ sec$^{-1}$, which will open the opportunity for studying new physics topics, such as Double Deeply Virtual Compton Scattering (DDVCS), accessible only with a high-luminosity, large-acceptance detector.

In this talk, the current performance of CLAS12, details of the upgrades to higher luminosities, and the new physics opportunities that these upgrades will open are discussed.

Orateur: Mariangela Bondì (INFN-Catania)

DIS2024_Bondi.pdf

171 Status and Prospects of the Electron-ion collider in China

As a future high energy nuclear physics project, an Electron-Ion Collider in China (EicC) has been proposed, to be constructed based on the High Intensity heavy-ion Accelerator Facility (HIAF) in Huizhou, China. The EicC will provide highly polarized electrons with a polarization of ~80% and protons with a polarization of ~70% with variable center of mass energies from 15 to 20 GeV and the luminosity of (2–3) $\times$ $10^{33}$ cm$^{-2}$s$^{-1}$. Polarized deuteron and helium-3, as well as unpolarized ion beams from Carbon to Uranium, will be also available at the EicC. The main foci of the EicC will be precision measurements of the structure of the nucleon in the sea quark region, including 3D tomography of nucleon; the partonic structure of nuclei and the parton interaction with the nuclear environment; the exotic states, especially those with heavy flavor quark contents. The status and prospects of the EicC project will be presented in this talk.

Orateur: Prof. Qinghua Xu (Shandong University)

EicC-DIS2024-QXu.pdf

172 Overview of the ePIC Detector

The Electron-Proton/Ion Collider Experiment (ePIC) Collaboration was formed to design, build, and operate the Electron-Ion Collider (EIC) project detector, which will be the first experiment at the collider. Positioned at the IP6 interaction region of the EIC accelerator, ePIC is poised to play a pivotal role in unraveling fundamental mysteries within the structure of visible matter by matching the whole scientific scope of the EIC project. To this end, ePIC measurements aim to address some of the most profound questions surrounding the emergence of nuclear properties by precisely imaging gluons and quarks inside protons and nuclei.

The ePIC detector technologies will enable intricate measurements of inclusive and semi-inclusive Deep Inelastic Scattering, as well as exclusive processes in electron-ion collisions. The ambitious physics goals and the constraints imposed by the challenging collider lattice result in the detector design, where several up-to-date and novel detector approaches have been selected.

The presentation will provide an overview of the ePIC detector related to its physics motivation, detailing its current status and outlining the innovative approaches in detector concepts and technologies that are being adopted.

Orateur: Shujie Li (Lawrence Berkeley National Laboratory)

epic_DIS2024_ShujieLi.pdf

10:40 Coffee Break

173 Particle Identification with the ePIC detector at the EIC

The ePIC detector is being designed as a general-purpose detector to deliver the full physics program of the Electron-Ion Collider (EIC) in BNL USA. Particle Identification (PID) plays a crucial role in the EIC physics scope. The PID system, globally covering the pseudorapidity range (from -3.3 to 3.5), supports the electromagnetic calorimeters in electron identification thanks to its pion/electron suppression capabilities. It provides the excellent hadron identification requested, in particular, for the Semi-Inclusive DIS (SIDIS) studies.

The compact size of the collider set up and physics requirements impose challenges and a single PID system can not deliver the full physics requirements. Therefore ePIC exploits multiple advanced PID technologies to overcome this challenge.

The presentation aims to describe the PID subsystems of the ePIC detector, with a specific emphasis on high-momentum particle-identification systems using RICH technology. The presence of the magnetic field of the experimental solenoid makes the choice of the photon sensors extremely challenging. The presentation will report about the studies made with SiPMs as the photosensor candidate for forward RICH detector. Also, studies made with novel LAPPD detectors and commercial MCP-PMT as photon sensors for the backward RICH and barrel DIRC system respectively will be discussed. The presentation will include a discussion on the simulation studies made with stand-alone Geant4 simulations and official ePIC software and simulation framework.

Orateur: Chandradoy Chatterjee (INFN Trieste)

Chatterjee_DIS2024_v5_final.pdf

174 Silicon Vertex Tracker for the ePIC experiment at the Electron-Ion Collider

Achieving outstanding tracking and vertexing accuracy over a wide kinematic range is essential for the physics program of the future Electron-Ion Collider (EIC). To address this need, the ePIC experiment at the EIC will exploit Monolithic Active Pixel Sensors in 65 nm CMOS imaging technology to realize a high-resolution, low material budget, and low power consumption Silicon Vertex Tracker. In this talk, we will present the detector design of the future SVT detector and the R&D being carried out to address the main technological challenges.

Orateur: Gian Michele Innocenti (MIT)

20240409_SVTePICDIS2024_Innocenti_UP2.pdf

175 Physics Perspectives with the ePIC Far-Forward and Far-Backward detectors

The forthcoming Electron-Ion Collider (EIC), expected to commence operations in the early 2030s, has already reached several significant milestones on its path toward completion. The core of the EIC physics program is the 3D imaging of partonic structures in protons and nuclei. The experimental detector setup required to enable this primary objective utilizes "Far-Forward" (FF) and "Far-Backward" (FB) detectors positioned downstream in the hadron-going and electron-going directions from the interaction point of the EIC, respectively. The primary purpose of the far-backward detectors is to monitor luminosity and measure scattered electrons in EIC collisions, while the array of far-forward detectors is used to tag and reconstruct both charged and neutral particles that scatter at small angles. These detectors also enable a broader physics program than was initially envisioned, enhancing the EIC's research potential. The expanded capabilities have been a prime focus for engaging the broader nuclear physics community to build a robust groundwork for the EIC. In this talk, I will describe the FF/FB detectors and review the advanced forward physics program facilitated by the FF/FB detectors at the EIC.

Orateur: Michael Pitt (Ben Gurion University of the Negev (IL))

FF_FB_detectors_ePIC_MPitt.pptx

176 Calorimetry for the ePIC Experiment

The EIC will deliver collisions of electrons with protons and nuclei at a wide variety of energies and at luminosities up to 1000 times higher than HERA. Precisely measuring both the scattered electron and the hadronic final state is crucial for the physics of the EIC, necessitating unique designs for the electromagnetic and hadronic calorimeters in the backward, central, and forward regions. To ensure maximal containment of energy and acceptance for the required physics processes, the ePIC detector employs calorimetry over almost the entire polar angle. This talk will provide an overview of the current calorimeter designs being employed in ePIC.

Orateur: Henry Klest (Argonne National Laboratory)

Klest DIS24 ePIC Final.pdf

Klest DIS24 ePIC Final.pptx

177 A 2nd Detector for the Electron-Ion Collider

The Electron-Ion Collider (EIC) is the next-generation US-based project for QCD and nuclear science. It will collide polarized electrons with polarized protons and light ions, as well as heavier ions across the full mass range, at a high luminosity, over a wide range of c.m. energies. The first detector (ePIC) will support a broad science program, but having two detectors would significantly expand the capabilities of the EIC. The possibility to cross check results between the two detectors will enhance its discovery potential, and as in the case of H1 and ZEUS, combining data could reduce the overall systematic uncertainties. The latter will be even more relevant for the EIC, since once the luminosity ramps up to its nominal value, most measurements will be limited by systematics. And those that require the highest luminosities (e.g., exclusive reactions and tomography of nucleons and nuclei) would greatly benefit from an improved far-forward near-beam acceptance, which is the main feature of the interaction region where the 2nd detector could be located. The ability to detect almost all nuclear fragments in reactions where the nucleus breaks up and a recoiling light nucleus in coherent processes will also enhance the nuclear part of the EIC program. The 2nd detector will also provide complementary capabilities to ePIC in other areas (e.g., improved muon detection), and will benefit from the ongoing Generic EIC Detector R&D program.

Orateur: Pawel Nadel-Turonski (CFNS Stony Brook)

PNT DIS EIC D2.pdf

PNT DIS EIC D2.pptx

WG2: Small-x, Diffraction and Vector Mesons 3

178 Describing the incoherent exclusive diffraction t-spectrum with hotspot evolution

Orateur: Tobias Toll (IIT Delhi)

DIS24_Toll.pdf

179 Incoherent J/ψ production at large |t| identifies the onset of saturation at the LHC

Orateur: Alexandra Ridzikova

pdf_version_ridzikova.pdf

ppt_version_ridz.pptx

180 Proton PDFs with non-linear corrections from gluon recombination

Orateur: Pit Duwentäster (University of Jyväskylä)

DIS24_Duwentaester.pdf

181 Predictions from the Balitsky-Kovchegov equation including the dipole orientation

Orateur: Matěj Vaculčiak (Czech Technical University in Prague)

24_dis.pdf

10:30 Coffee break

182 Azimuthal anisotropy from quantum interference in $\rho^0$ photoproduction in ultra-peripheral collisions with ALICE

Orateur: Andrea Giovanni Riffero (University and INFN Torino (IT))

azimuth-anis-dis2024-riffero.pdf

183 Probing gluon saturation and nuclear structure in photon-nucleus collisions

Orateur: Heikki Mäntysaari (University of Jyväskylä)

DIS2024_talk_diffractive_VM-6.pdf

184 First study of the initial gluonic fluctuations using UPCs with ALICE

Orateur: David Grund (Czech Technical University in Prague)

fluctJpsi_DIS2024.pdf

185 Inferring the Initial Condition for the BK Equation

Orateur: Carlisle Aurabelle Casuga

dis2024_carlislecasuga.pdf

186 K+K− photoproduction in ultra-peripheral Pb–Pb collisions with ALICE

Orateur: Minjung Kim (UC Berkeley)

DIS2024_KKproduction_MJKIM.pdf

12:40 Lunch

WG1: Structure Functions and Parton Densities 4

187 Preliminary Results from the 12 GeV EMC Effect Experiment in Hall C of Jefferson Lab

Results published in 1983 by the European Muon Collaboration (EMC) at CERN suggested that a nucleon's partonic structure is modified when multiple nucleons are bound together in the nuclear environment. This phenomenon, now known as the EMC Effect, came as a surprise due to the relatively small energies involved in nucleon-nucleon interactions when compared to the energies present in DIS interactions. The EMC Effect has been the subject of a significant amount of theoretical and experimental effort over the past forty years to determine its underlying cause. Despite this effort, the driving mechanism behind the EMC Effect has yet to be determined.

To help solve this decades-old puzzle, experiment E12-10-008 was conducted at Jefferson Lab. Data was collected from Fall 2022 through Spring 2023, utilizing the high luminosity 12 GeV electron beam of CEBAF to probe the partonic structure of the different nuclei. In this talk, I will give an overview of the EMC Effect, highlight the key physics goals of experiment E12-10-008, and present preliminary results from our analysis.

Orateur: Cameron Cotton (University of Virginia)

Cotton_DIS2024.pdf

188 COMPASS Results on Pion, Kaon and Unidentified Hadrons Multiplicities from SIDIS on Proton Target

New preliminary results from COMPASS on pion and kaon multiplicities in Semi-Inclusive Deep Inelastic Scattering on a proton target are presented. These proton findings serve as a complementary dataset to the deuteron results published in 2017. In this updated analysis, we have implemented an enhanced treatment of Radiative Corrections using DJANGOH MC. A comparison with the previously employed method reveals relative differences of up to 12% in terms of multiplicities. Despite these modifications, the preliminary COMPASS kaon results continue to exhibit incompatibility with those from HERMES. The presented results will provide an important input for global fragmentation function fits.

Orateur: Marcin Stolarski (LIP- Lisboa)

stolarski_dis_24.pdf

189 Fantômas4QCD: pion PDFs with epistemic uncertainties

In light of recent progress on both the experimental and lattice-QCD sides, our understanding of the pion’s structure has evolved. Phenomenological, or global, QCD analyses — the focus of this talk— play a crucial role in establishing a bridge between experimental data, theoretical predictions, and lattice-QCD studies. I will present recent efforts in the determination of the distribution of partons in the pion, with an emphasis on uncertainty quantification. The Fantômas project aims to explore the role of parametric forms for the distribution of quarks and gluons in the final uncertainty that results from the global analysis. To achieve this objective, the Fantômas project employs Bézier curves for generating diverse functional forms for the PDFs. The selection process for the final set of solutions hence involves sampling over the parametrization space, allowing for a comprehensive exploration of uncertainties.

Orateur: Aurore Courtoy (Instituto de Física, UNAM)

DIS_24_AC.pdf

190 Extraction of kaon partonic distribution functions from Drell-Yan and J/psi production data

We present an analysis to extract kaon parton distribution functions (PDFs) using meson-induced Drell-Yan and quarkonium production data. Starting from the statistical model, first developed for describing the partonic structure of nucleons and later applied to the pion, we have extended this approach to perform a global fit to existing kaon-induced Drell-Yan and charmonium production data. These data are well described by the statistical model, allowing an extraction of the kaon PDFs. We find that both the Drell-Yan and the charmonium data favor a harder valence distribution for strange quark than for up quark in kaon. The kaon gluon distribution is further constrained by the charmonium production data. In particular, the momentum fraction carried by gluons is found to be similar for pion and kaon.

Orateur: Jen-Chieh Peng (University of Illinois at Urbana-Champaign)

DIS_2024_Peng.pdf

DIS_2024_Peng.pptx

15:30 Coffee break

191 Partonic collinear structure by quantum computing

We present a systematic quantum algorithm, which integrates both the hadronic state preparation and the evaluation of real-time light-front correlators, to study parton distribution function (PDF) and light cone distribution amplitude (LCDA). As a proof of concept, we demonstrate the first direct simulation of the PDF and LCDA in the 1+1 dimensional Nambu-Jona-Lasinio model. We show the results obtained by exact diagonalization and by quantum computation using classical hardware. The agreement between these two distinct methods and the qualitative consistency with QCD PDFs validate the proposed quantum algorithm. Our work suggests the encouraging prospects of calculating QCD PDFs on current and near-term quantum devices. The presented quantum algorithm is expected to have many applications in high energy particle and nuclear physics.

Orateur: Hongxi Xing (South China Normal University)

Xing_0410.pdf

192 PartonDensity.jl: a novel parton density determination code

We introduce our novel Bayesian parton density determination code, \partondensity. The motivation for this new code, the framework and its validation are described. As we show, \partondensity provides both a flexible environment for the determination of parton densities and a wealth of information concerning the knowledge update provided by the analyzed data set.

Orateur: Allen Caldwell (Max Planck Institute for Physics)

DIS2024.pdf

193 Analytic Solutions of the DGLAP Evolution and Theoretical Uncertainties

The energy dependence for the singlet sector of Parton Distributions Functions (PDFs) is described by an entangled pair of ordinary linear differential equations. Although there are no closed analytic solutions, it is possible to provide approximated results depending on the assumptions and the methodology adopted. These results differ in their sub-leading, neglected terms and ultimately they are associated with different treatments of the theoretical uncertainties. In this talk, a novel analytic approach in Mellin space is presented and different analytic results for the DGLAP evolution at Next-Lowest-Order are compared. Advantages and disadvantages for each solution are discussed and generalizations to higher orders are addressed.

Orateur: Andrea Simonelli (Old Dominion University and Jefferson Lab)

DIS2024-WG1_Simonelli.pdf

WG5: Spin and 3D Structure 4

194 PHENIX-Spin Highlights

After two decades of RHIC running as a polarized proton collider, we summarize recent achievements of the PHENIX spin program and their impact on our understanding of the nucleon’s spin structure on partonic level (e.g. quark and gluon spin contribution to the spin of the proton), and transverse spin phenomena giving access to parton dynamics within the nucleon. Of particular interest are surprising results from collisions of polarized protons on nuclei, which open novel opportunities to study nuclear effects with spin observables.

Orateur: Dr Alexander Bazilevsky (Brookhaven National Laboratory)

PHENIX_Spin_DIS24.pdf

195 Transverse-spin asymmetries in COMPASS Drell-Yan data

Abstract: Studies of the transverse-spin dependent azimuthal asymmetries in the Drell-Yan process permit to access the spin-dependent structure of the nucleon and especially to test the limited universality of its transverse-momentum dependent parton distributions. In 2015 and 2018 the COMPASS Collaboration at CERN performed measurements of the $\pi^-$p $\rightarrow \mu^+\mu^-$X reaction at 190 GeV/$c$ pion beam and transversely polarised NH$_3$ target. This study covers the measurement of Transverse Spin Asymmetries in Drell-Yan processes, and in particular, introduces a novel approach, in contrast to the conventional one, where the asymmetries were weighted by powers of a transverse momentum of the dimuon system with respect to the beam. This method facilitates the extraction of the transverse-momentum dependent parton distribution functions and opens an easy access to their certain $k_{\rm T}^2$ moments. Results of these analyses together with a comparison with results obtained in the semi-inclusive muon production will be presented.

Orateur: Małgorzata Niemiec (University of Warsaw)

MNiemiec_DIS2024.pdf

196 Disentagling soft effects from TMD Fragmentation Functions

Transverse Momentum Dependent (TMD) factorization leads to well established theorems for a restricted class of processes. In such cases, some of the effects produced by the soft radiation cancel out and the physics associated to them cannot be accessed. Extension of the factorization to non-standard processes inevitably leads to deal with the non trivial structure of the soft sector, revealing details that in the standard cases are not accessible. In particular, comparing the extraction of the TMD Fragmentation Function obtained from SIDIS with that extracted from single-inclusive $e^+e^-$ annihilation gives access to a new universal non-perturbative function describing the long-distance behavior of soft gluons and potentially revealing hidden properties of the QCD vacuum. In this talk, I present such comparison among the most recent phenomenological extractions and I will provide the first quantitative estimate of these hidden soft effects.

Orateur: Andrea Simonelli (Old Dominion University and Jefferson Lab)

DIS2024 - WG5_Simonelli.pdf

197 Phenomenology of TMD parton distributions in Drell-Yan and $Z^0$ boson production in a hadron structure oriented approach

We present a first practical implementation of a recently proposed hadron structure oriented (HSO) approach to TMD phenomenology applied to Drell-Yan like processes, including lepton pair production at moderate $Q^2$ and $Z^0$ boson production.
We compare and contrast general features of our methodology with other common practices and emphasize the improvements derived from our approach that we view as essential for applications where extracting details of nonperturbative transverse hadron structure is a major goal. These include the HSO's preservation of a basic TMD parton-model-like framework even while accounting for full TMD factorization and evolution, explicit preservation of the integral relationship between TMD and collinear pdfs, and the ability to meaningfully compare different theoretical models of nonperturbative transverse momentum dependence.
In our examples, we show that there is significant sensitivity at moderate $Q^2$ to both the form of the nonperturbative transverse momentum dependence and the parametrization of collinear parton densities. However, we also find that evolving to $Q^2 = M_Z^2$, without fitting, results in a satisfactory postdiction of existing data for $Z^0$ production, nearly independently of the modeling of nonperturbative transverse momentum dependence. We argue that this demonstrates that moderate $Q$ measurements should be given greater weight than high $Q$ measurements in extractions of nonperturbative transverse momentum dependence.
We also obtain new extractions of the nonperturbative Collins-Soper kernel within the HSO approach. We discuss its features and compare with some earlier extractions.

Orateur: Tommaso Rainaldi (Old Dominion University)

Rainaldi_DIS24.pdf

15:30 Coffee Break

198 Measurement of Transverse Spin Dependent Azimuthal Correlation Asymmetry and Unpolarized Cross-Section of Oppositely-Charged Pion Pairs in Proton-Proton Collisions at STAR

The transversity distribution function, $h_1^q(x)$, describes the transverse quark polarization within a transversely-polarized nucleon, where $x$ is the longitudinal momentum fraction carried by quark $q$. Being chiral-odd, $h_1^q(x)$ can be accessed only when coupled with another chiral-odd function, such as the spin-dependent interference fragmentation function (IFF) via the di-hadron channel ($\pi\pi$, $\pi K$, $KK$, etc., in the final state). In transversely polarized proton-proton collisions ($p^\uparrow p$), the di-hadron azimuthal correlation asymmetry, $A_{UT}^{h_1h_2}$, that originates from the interplay between the spin of the fragmenting quark and the final state di-hadron, can be measured. This $A_{UT}^{h_1h_2}$ involves the convolution of $h_{1}^{q}(x)$ and IFF. However, this channel requires knowledge not only of IFF but also of the unpolarized parton fragmentation functions (FFs), specifically for gluons. Therefore, obtaining the unpolarized di-hadron cross-section ($d\sigma_{UU}^{h_1h_2}$) in $pp$ is crucial to constrain gluon FF and, consequently, $h_1^q(x)$. We will present preliminary results on $A_{UT}^{\pi^+\pi^-}$ using $p^\uparrow p$ data collected by the STAR experiment at RHIC at center-of-mass energies ($\sqrt{s}$) of 200 and 510 GeV from the 2015 and 2017 datasets, with integrated luminosities ($\mathcal{L}_{int}$) of 52 and 350 $\rm pb^{-1}$, respectively. Additionally, we will present the preliminary result of the $d\sigma_{UU}^{\pi^+\pi^-}$ using $pp$ data at $\sqrt{s} = 200$ GeV ($\mathcal{L}_{int} = $ 14 $\rm pb^{-1}$) from 2012 dataset.

Orateur: Prof. Bernd Surrow (Temple University)

BSurrow-DIS2024_IFF_DiHadron.pdf

199 Transverse Single Spin Asymmetry of Electromagnetic Jets for Inclusive and Single Diffractive Process at Forward Rapidity in p^{\uparrow}+p Collisions at \sqrt{s} = 200 GeV at STAR

In recent decades, there have been numerous efforts to unravel the origin of the unexpectedly significant transverse single spin asymmetry ($A_{N}$) observed in inclusive hadron productions at forward rapidities in $p^{\uparrow}$+$p$ collisions at various center-of-mass energies ($\sqrt{s}$). Several theories have been proposed to explain this phenomenon, including the twist-3 contributions within the collinear factorization framework, the transverse-momentum-dependent contributions from the initial-state quark and gluon (Sivers functions), and/or final-state Collins fragmentation functions. However, there are indications that diffractive processes might also play a role in the observed significant $A_{N}$, based on the previous analyses of $A_{N}$ for forward $\pi^{0}$ and electromagnetic jets (EM-jets) in $p^{\uparrow}$+$p$ collisions at STAR [1].

The STAR experiment provides an ideal opportunity to investigate the $A_{N}$ in single diffractive processes at forward rapidity using the Forward Meson Spectrometer and Roman Pot detectors.
This talk will present the preliminary findings on $A_{N}$ for both inclusive and single diffractive EM-jets at forward rapidity ($2.6 < \eta < 4.2$) in $p^{\uparrow}$+$p$ collisions at $\sqrt{s} =$ 200 GeV at STAR. The discussion will include a multi-dimensional analysis of $A_{N}$ for EM-jets in inclusive processes, with a focus on presenting the first preliminary results for $A_{N}$ in single diffractive processes. Additionally, there will be a discussion on the contribution of $A_{N}$ from single diffractive processes to the overall inclusive processes.

[1] (STAR) J. Adam et, al., Phys. Rev. D 103, 092009 (2021)

Orateur: Xilin Liang (University of California, Riverside)

Liang_DIS2024_slide_final.pdf

200 Azimuthal transverse single-spin asymmetries of inclusive jets and hadrons within jets from polarized ${pp}$ collisions at $\sqrt{s}$ = 510 GeV

Studies on the origin of transverse single-spin asymmetries have triggered the development of the twist-3 formalism and transverse-momentum-dependent parton distribution functions (TMDs). Measurement of the azimuthal distribution of identified hadrons within a jet in transversely polarized hadronic interactions provides an opportunity to study TMD physics, such as the Collins effect, which involves quark transversity and the Collins fragmentation functions. STAR has published measurements of Collins asymmetries from jet + $\pi^{\pm}$ production in transversely polarized ${pp}$ collisions at a center-of-mass energy of $\sqrt{s}$ = 500 GeV, based on data taken in 2011 with an integrated luminosity of 23 $\mathrm{pb}^{-1}$. This was supplemented by an extensive measurement of azimuthal transverse single-spin asymmetries of inclusive jets and hadrons within jets from transversely polarized ${pp}$ collisions at $\sqrt{s}$ = 200 GeV, using data from 2012 and 2015. In 2017, STAR collected a significantly larger ${pp}$ dataset with an integrated luminosity of 350 $\mathrm{pb}^{-1}$ at $\sqrt{s}$ = 510 GeV, which will further improve the precision of the transverse single-spin asymmetry measurements especially at high jet transverse momentum region. In this talk, we will report preliminary results of azimuthal transverse single-spin asymmetries for inclusive jets and charged pions within jets from transversely polarized ${pp}$ collisions at $\sqrt{s}$ = 510 GeV that took place in 2017.

Orateur: Yike Xu

DIS2024_xuyike.pdf

201 The Sivers asymmetry of the vector mesons production in the semi-inclusive deep inelastic scattering

The transverse single spin asymmetries (TSSAs) in semi-inclusive deep inelastic scattering (SIDIS) have been intensively investigated over the last two decades. The TSSAs of $\rho^{0}$ are recently measured by COMPASS. Among these, the Sivers asymmetry can be expressed within the transverse momentum dependent (TMD) factorization framework, as the convolution of the Sivers function of the nucleon and the unpolarized fragmentation function of the final-state hadron. We perform a phenomenological study and find that the COMPASS data can be well described by the Sivers function extracted from SIDIS data with pion and kaon production. This finding serves as a test for the universality of the Sivers function within the current experimental precision. Based on these results, we predict the Sivers asymmetry of $\rho^{0}$ and $K^{*}$ in future facilities, such as electron-ion colliders and the Jefferson Lab 22 GeV (JLab22).

Orateur: Yongjie Deng (Shandong University)

SiversAsymmetryRho0_DIS2024.pdf

202 New measurement of transverse spin effects in hadron production from muon-deuteron semi-inclusive DIS at COMPASS

COMPASS is a fixed target high energy physics experiment that has been collecting data for 20 years (2002 to 2022) at the M2 beamline (SPS, North Area) at CERN. One of the goals of the experiment's broad physics program was to perform semi-inclusive measurements of target-spin dependent asymmetries in (di-)hadron production in DIS with high-energy muons colliding with polarised targets. The latest COMPASS semi-inclusive DIS measurements were performed in 2022 using a transversely polarised deuteron target and a 160 GeV/$c$ muon beam. They balance the existing data collected with transversely polarised proton targets and thus play a crucial role in constraining the d-quark transversity and Sivers functions.

This talk will present first results from about two thirds of the new 2022 data.

Orateur: Siranush Asatryan (A. Alikhanyan National Laboratory)

Asatryan_DIS2024.pdf

203 Pion-induced Drell-Yan cross-section measurements at COMPASS

Pion-induced Drell-Yan muon-pair production is one of the key processes providing information on the structure of the $\pi$ meson. In this channel, the world data set is limitted to the cross-section measurements performed by the NA10 and E615 experiments more than 30 years ago. In 2015 and 2018, the COMPASS experiment at CERN collected data sensitive to the Drell-Yan process using a 190 GeV negative pion beam scattering off an NH3 target and two nuclear targets: aluminium and tungsten. The recent results of the differential cross sections of Drell-Yan muon-pair production measured by the COMPASS Collaboration will be presented. The kinematic domain is restricted to dimuon invariant masses between 4.3 and 8.5 GeV/$c^2$ and spans the Feynman-x region from -0.2 to 0.9 and transverse momenta up to 3.6 GeV/$c$. The results are a valuable input for constraining the collinear and transverse momentum dependent parton distribution functions of the pion.

Orateur: Vincent Andrieux (University of Illinois at Urbana-Champaign)

Andrieux_DIS20240410.pdf

204 Global fit of unpolarized Transverse Momentum Distributions

In this talk we present the latest results by the MAP Collaboration about the extraction of unpolarized quark Transverse-Momentum-Dependent Distributions (TMD PDFs) and Fragmentation Functions (TMD FFs) from global fits of Drell-Yan and Semi-Inclusive Deep-Inelastic Scattering (SIDIS) data sets.

Orateur: Lorenzo Rossi (University of Pavia & INFN)

DIS_2024_Rossi.pdf

205 Role of the twist-3 gluon effect on the single transverse-spin asymmetry in the semi-inclusive J/psi production

The understanding of the gluon Sivers effect is one of the main objectives of current and future experiments as a possible solution to the large single transverse-spin asymmetry(SSA) which has been a mystery in high energy QCD over 40 years. The collinear twist-3 framework has been a successful perturbative QCD framework for the description of the SSA in the high transverse momentum region of a production hadron. In the case of heavy quarkonium productions, the twist-3 gluon Sivers effect is expected to play a role as an origin of the SSA. In this talk, we will show the first systematic calculation for the J/psi SSA within the twist-3 framework combined with non-relativistic QCD framework which gives a reliable treatment of the hadronization of a heavy quark-antiquark pair into a heavy quarkonium. Our result is necessary for the on-going measurement at RHIC and future investigations at electron-ion colliders.

Orateur: Shinsuke Yoshida (South China Normal University)

DIS2024_yoshida2.pdf

WG6: Joint WG3-WG6

206 Backward DVCS on the pion in Sullivan processes

The purpose of this work is to do a systematic feasibility study of measuring in backward region deeply virtual Compton scattering on the pion in Sullivan processes in the framework of collinear QCD factorization where pion to photon transition distribution amplitudes (TDAs) describes the photon content of the $\pi$ meson. Our approach employs TDAs based on the overlap of light front wave functions, using a previously developed pion light-front wave function and deriving a consistent model for the light front wave functions of the photon. Our results for the TDAs are compared with previous models found in the literature. This work is expected to lead us to an estimate of the cross-sections that could be measured in the future U.S. and China's electron ion colliders, once the computations are completed. It will also provide a comparison with the forward Sullivan DVCS case, for which a strong signal is expected.

Orateur: Abigail Castro (CEA)

ACastro_dis_2024.pdf

207 The general-purpose LHeC and FCC-eh high-energy precision programme: Top and EW measurements

The Large Hadron-electron Collider and the Future Circular Collider in electron-hadron mode [1] will make possible the study of DIS in the TeV regime providing electron-proton collisions with instantaneous luminosities of $10^{34}$ cm$^{−2}$s$^{−1}$. In this talk we will review the opportunities for measuring standard and anomalous top quark couplings, both to lighter quarks and to gauge bosons, flavour changing and conserving, through single top quark and $t\bar t$ production. We will discuss the studies in inclusive DIS of different EW parameters like the effective mixing angle and the gauge boson masses, and the weak neutral and charged current couplings of the gauge bosons. We will also review the possibilities in direct $W$ and $Z$ production, and analyse the implications of a precise determination of parton densities at the LHeC or FCC-eh on EW measurements at hadronic colliders. Special emphasis is given to possibilities to empower $pp$ and $e^+e^-$ physics at the LHC and FCC.
[1] LHeC Collaboration and FCC-he Study Group: P. Agostini et al., J. Phys. G 48 (2021) 11, 110501, e-Print: 2007.14491 [hep-ex].

Orateur: Nestor Armesto (IGFAE, Universidade de Santiago de Compostela)

Armesto_DIS2024_10042024.pdf

208 Searches for new physics at the LHeC and FCC-eh+ Higgs precision Higgs physics in electron–proton scattering at CERN

The Large Hadron-electron Collider and the Future Circular Collider in electron-hadron mode [1] will make possible the study of DIS in the TeV regime providing electron-proton collisions with per nucleon instantaneous luminosities of $10^{34}$ cm$^{−2}$s$^{−1}$. We review the possibilities for detection of physics beyond the SM in these experiments, focusing on feebly interacting particles like heavy neutrinos or dark photons, on anomalous gauge couplings, and on theories with heavy resonances like leptoquarks, or with contact interactions. We will emphasise the complementarity of searches at the LHeC (FCC-eh), and the respective hadronic colliders, the HL-LHC and the FCC-hh, and $e^+e^-$ Higgs factories.
[1] LHeC Collaboration and FCC-he Study Group: P. Agostini et al., J. Phys. G 48 (2021) 11, 110501, e-Print: 2007.14491 [hep-ex].

The Large Hadron-electron Collider and the Future Circular Collider in electron-hadron mode [1] will make possible the study of DIS in the TeV regime providing electron-proton collisions with instantaneous luminosities of cms. With a charged current cross section around 200 (1000) fb at the LHeC (FCC-eh), Higgs bosons will be produced abundantly. We examine the opportunities for studying several of its couplings, particularly
,
, , and Higgs to invisible. We also discuss the possibilities to measure anomalous Higgs couplings, and the implications of precise parton densities measured in DIS on Higgs physics. We finally address the complementarity in measuring Higgs couplings between the LHeC and the FCC-he and the respective hadronic colliders, the HL-LHC and the FCC-hh, and Higgs factories, but will also emphasise the gain in accuracy achievable by combining results between those colliders.
[1] LHeC Collaboration and FCC-he Study Group: P. Agostini et al., J. Phys. G 48 (2021) 11, 110501, e-Print: 2007.14491 [hep-ex].

Orateur: Bruce Mellado

DIS2024_ep_Higgs_BSM_100424.pdf

209 High energy $\gamma\gamma$ interactions at the LHeC

The future collider LHeC is set to operate at a center-of-mass energy of 1.2 TeV and is anticipated to provide an integrated electron-proton luminosity of 1 ab$^{-1}$. This talk aims to present a comprehensive survey of studies of high-energy photon-photon processes at the LHeC, for
the $\gamma \gamma$ center-of-mass energy of up to 1~TeV.
The scientific potential of studying such photon-photon interactions is
evaluated by discussions of cross sections for various $\gamma \gamma$
processes, including, in particular, the exclusive production of
pairs of W and Z bosons, lepton pairs, Higgs bosons as well as
pairs of charged supersymmetric particles.

Orateur: Hamzeh Khanpour (AGH University of Science and Technology, Krakow, Poland)

15:25 Coffee Break

210 Overview of the MOLLER experiment at JLab

The MOLLER experiment has been designed to significantly expand the reach for new dynamics beyond the Standard Model of electroweak interactions. Using the high intensity, high precision electron beam at Jefferson Lab, MOLLER will measure the parity-violating asymmetry $A_{PV}$ in the scattering of longitudinally polarized electrons off unpolarized electrons to an overall fractional accuracy of 2.4%. This measurement will be the most sensitive probe of new flavor- and CP-conserving neutral current interactions in the leptonic sector until the advent of a linear collider or neutrino factory. The collaboration has begun fabrication of the required apparatus, with an assembly expected to complete in JLab's experimental Hall A in 2026. The experimental design will be reviewed, along with the updated status and plans for executing the measurement.

Orateur: Kent Paschke (University of Virginia)

Paschke_DIS2024.pdf

211 Parity Quality Electron Beam for the MOLLER Experiment

The aim of the upcoming MOLLER experiment at Jefferson Laboratory, a national accelerator facility, is to probe electroweak interactions with unprecedented sensitivity reach at both low and high energy scales to discover new beyond the Standard Model dynamics. MOLLER is an extremely precise measurement of parity violation in electron scattering searching for new neutral currents in electron-electron scattering. The measurement relies on a high precision comparison of scattering rates for opposite beam helicity polarization, and ensuring tight limits on polarization-dependent asymmetries in the electron beam is a key technical challenge. This talk will be geared towards describing techniques to be employed to meet the stringent systematic uncertainty goals arising from beam asymmetries in parity experiments for thee upcoming MOLLER experiment.

Orateur: Caryn Palatchi (Indiana University)

20240410_DISmeetingBeamControlMollerPREXCREX_ver3shortere.pdf

212 Long-lived particle searches with the ILD experiment

Future e$^+$e$^-$ colliders, with their clean environment and triggerless operation, offer a unique opportunity to search for long-lived particles (LLPs). Considered in this contribution are prospects for LLP searches with the International Large Detector (ILD) providing almost continuous tracking in Time Projection Chamber (TPC) as the core of its tracking systems. The ILD has been developed as a detector concept for the ILC, but is also applicable to other Higgs Factory options.

The considered signature for neutral LLP production is a highly displaced decay vertex, which we search for in the TPC. Based on the full detector simulation, we study decays of both light and heavy LLPs. For the heavy, $\mathcal{O}(100$ GeV) LLPs, the most challenging scenarios are those with a small mass splitting between LLP and a dark matter candidate, resulting in only a very soft displaced track pair in the final state, not pointing to the interaction point. As the opposite extreme scenario we consider the production of light, $\mathcal{O}(1$ GeV) pseudo-scalar LLP, which decays to two highly boosted and almost colinear displaced tracks. Backgrounds both from soft beam-induced processes and hard physical events are taken into account. Assuming a single displaced vertex signature, the limits on signal production cross-section are presented for a wide range of LLP lifetimes and a set of masses or mass splittings. These limits are to a large extent model-independent, reflecting kinematic properties of the considered signature. They can be used to set limits on particular models, also for more complex signatures involving displaced vertices.

Orateur: Jan Klamka (University of Warsaw (PL))

llp_dis2024_jklamka.pdf

WG2: Small-x, Diffraction and Vector Mesons 4

213 Next-to-leading order photon+jet production

Orateur: Yair Mulian (Saclay CEA)

dis24_phjet.pdf

214 Diffractive processes at the NLO in a saturation framework

Orateur: Michael Fucilla (Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405, Orsay, France)

DIS2024_Fucilla.pdf

215 Precision studies of gluon saturation in DIS at small x: NLO corrections to SIDIS and double inclusive hadron production

Orateur: Jamal Jalilian-Marian (Baruch College, City University of New York)

jjm-dis-04-2024.pdf

216 Exclusive four pion photoproduction in ultra-peripheral Pb–Pb collisions at √sNN = 5.02 TeV at ALICE

Orateur: Alexander Bylinkin (University of Bergen)

DIS_2024_fourpi_final.pdf

15:30 Coffee break

217 Confronting Next-to-Leading Order CGC/Saturation Approach with HERA Data

Orateur: Jose Garrido (Universidad Técnica Federico Santa María)

JoseG_DIS2024.pdf

218 Resummation in JIMWLK Hamiltonian

Orateur: Michael Lublinsky

talk_DIS_2024.pdf

219 Reconciling the kinematical constraint with the JIMWLK evolution equation

Orateur: Piotr Korcyl (Institute of Theoretical Physics, Jagiellonian University)

DIS2024_Grenoble_PiotrKorcyl.pdf

220 A unified description of DGLAP, CSS, and BFKL: TMD factorization bridging large and small x

Orateur: Swagato Mukherjee (Brookhaven National Laboratory)

Mukherjee.pdf

221 Transverse energy-energy correlators in the Color-Glass Condensate

Orateurs: Jani Penttala (UCLA), Jani Penttala

Penttala_DIS_2024_v4.pdf

222 Harmonics of Lepton-Jet Correlations in inclusive and diffractive scatterings

Orateur: Xuanbo Tong

LJC_Tong_DIS2024.pdf

223 Conference banquet info!

info

WG4: QCD with Heavy Flavours and Hadronic Final States 4

224 Measurements of W and Z boson production in association with jets in ATLAS

The production of W/Z bosons in association with light or heavy flavor jets or hadrons at the LHC is sensitive to the flavor content of the proton and provides an important test of perturbative QCD. In this talk, measurements by the ATLAS experiment probing the charm and beauty content of the proton are presented. Inclusive and differential cross-sections of Z boson production with at least one c-jet, or one or two b-jets are measured for events in which the Z boson decays into a pair of electrons or muons. Predictions from several Monte Carlo generators based on next-to-leading-order (NLO) matrix elements interfaced with a parton-shower simulation, with different choices of flavour schemes for initial-state partons, are compared with the measured cross sections. Moreover, the production of W boson in association with D+ and D*+ mesons will be discussed. This precision measurement provides information about the strange content of the proton. Measurements are compared to the state-of-the-art NLO theoretical calculations. Finally, measurements of inclusive, differential cross sections for the production of missing transverse momentum plus jets are presented. The measurements are designed both to allow comparison to Standard Model predictions, and to be sensitive to potential extensions to the Standard Model, particularly those involving the production of Dark Matter particles.

Orateur: Camilla Vittori

DIS2024_10-4-2024.pdf

225 Combining NNLO QCD corrections with parton showers for Higgs production in bottom-quark fusion

With the growing precision of experimental measurements, combining fixed-order perturbative calculations with parton-shower effects becomes essential for an accurate description of LHC phenomenology. In this talk, we focus on the computation of Higgs production via bottom-quark annihilation ($b \bar{b}H$) at next-to-next-to-leading order (NNLO) in QCD perturbation theory, consistently matched with parton showers (NNLO+PS) using the MiNNLOPS technique. We extend the MiNNLOPS framework to accommodate a scale-dependent Yukawa coupling renormalized in the $\overline{\rm MS}$ scheme. Given the flexibility in schemes for the $b \bar{b}H$ process calculation, where the bottom quark can be treated as massless or massive at the LHC production scale, we explore both the five-flavour scheme (5FS) with massless bottom quarks and the four-flavour scheme (4FS) incorporating massive bottom quarks. In the 4FS computation, we employ the MiNNLOPS method tailored for the QQF scenario, featuring a heavy quark (Q) and a color singlet final state (F).

Orateur: Aparna Sankar (Max Planck Institute for Physics Munich)

DIS2024.pdf

226 Partial N3LL + NNLO Resummed Predictions for the Drell-Yan Process in Rapidity Dependent Jet Veto Observables

Jet vetoes are important tools that are frequently used to cut away backgrounds or separate different hard scattering processes. The most commonly used variable to veto jets is the simple transverse momentum of a jet. However it can be useful to use a jet veto that is tight in transverse momentum at central rapidities, and gradually becomes looser as one goes forward in rapidity - for example, to reduce sensitivity to jets from pile-up and the underlying event. This naturally leads to a class of such variables related to the leading jets transverse momentum weighed by some rapidity dependent function.

Applying tight cuts on such variables requires resummation of large logarithms of the hard scale over the jet veto scale. I will discuss the resummation of two different rapidity dependent jet veto observables, and present new results at partial N3LL + NNLO for the Drell-Yan process with these two jet vetoes applied. Comparing these predictions with experimental results should provide an interesting new test of our understanding of QCD radiation, as these rapidity dependent vetoes divide the phase space in a quite different way from the traditional transverse momentum veto.

Based on work done with Shireen Gangal and Jonathan Gaunt.

Orateur: Thomas Clark (University of Manchester)

Partial N3LL + NNLO Resummed Predictions for the Drell-Yan Process in Rapidity Dependent Jet Veto Observables v3.pdf

227 Six-jet production via triple parton scatterings in p-p and p-Pb collisions at the LHC

High-energy collisions of hadrons (protons and nuclei) at the CERN Large Hadron Collider (LHC) are characterized by multiple interactions of their underlying partonic constituents. The simultaneous production of several particles with large transverse momentum and/or mass ($p_\mathrm{T}, m \gg 3$~GeV) in different independent hard partonic interactions has attracted an increasing interest in collider physics as a means to study the energy evolution of the parton profile of the nucleons in the transverse direction, to probe the generalized parton densities of hadrons, and to investigate the role of partonic correlations in the hadronic wave functions.
Thanks to the large center-of-mass and integrated luminosities available at the LHC, the production of three independent parton scatterings in a given proton-proton (p-p) or proton-nucleus (p-Pb) collision is measurable for the first time. This work presents results on the production of six jets in p-p and p-Pb collisions as a means to study Triple Parton Scattering (TPS) processes. The work exploits a multi-variate-analysis based on different kinematic properties of the outgoing jets to separate the TPS signal from single- and double-parton scattering processes, and obtain the expected statistical significances for their observation.

Orateur: Marina Maneyro (University of Liverpool)

SixjetTPS_Maneyro_DIS.pdf

15:30 Coffee break

228 di-jet production and signatures of collectivity in multiparticle photoproduction in UPC with the ATLAS detector

Abstract 215:

In relativistic heavy ion collisions, the charged ions produce an intense flux of equivalent photons. Thus, photon-induced processes are the dominant interaction mechanism when the colliding nuclei have a transverse separation larger than the nuclear diameter. In these ultra-peripheral collisions (UPCs), the photon provides a clean, energetic probe of the partonic structure of the nucleus, analogous to deep inelastic scattering. This talk presents a measurement of jet production in UPCs performed with the ATLAS detector using high-statistics 2018 Pb+Pb data. Events are selected using requirements on jet production, rapidity gaps, and forward neutron emission to identify photo-nuclear hard-scattering processes. The precision of these measurements is augmented by studies of nuclear break-up effects, allowing for detailed comparisons with theoretical models in phase-space regions where significant nuclear PDF modifications are expected but not strongly constrained by existing data.

Abstract 216:
Ultraperipheral collisions of relativistic heavy ion beams lead to a diverse set of photon-nucleus (photonuclear) interactions. The measurements of particle production in photonuclear reactions can shed light on the QCD dynamics of the novel, extremely asymmetric colliding systems, with energies between those available at RHIC and the LHC. Previous studies by ATLAS indicate significant elliptic and triangular flow coefficients in these events. Thus, it is imperative to check these events for other potential QGP signatures such as radial flow. This talk presents the measurement of charged hadron yields in photonuclear collisions using 5.02 TeV Pb+Pb data collected in 2018 by ATLAS. The charged hadron yields are presented as a function of pseudorapidity and transverse momentum in different categories of event multiplicity. The results are compared with 5.02 TeV p+Pb data collected in 2016 by ATLAS at the same event multiplicities. The results are also compared with calculations from DPMJET and hydrodynamic-based models. These comparisons enable detailed characterizations of photonuclear collision properties, including the photon energy distribution and whether small QGP droplets may be formed.

Orateur: Martin Spousta

Spousta_DIS2024-20240325.pdf

229 Dijet photoproduction and transverse-plane geometry in ultra-peripheral nuclear collisions

Inclusive photoproduction of dijets in ultra-peripheral nucleus-nucleus collisions (UPCs) has been suggested as a new probe for studying the nuclear parton distributions (nPDFs). In this talk, we present new NLO pQCD predictions for the photoproduction of dijets in PbPb UPCs at 5.02 TeV with up-to-date nPDFs and realistic impact-parameter dependent photon flux obtained through the nuclear form factor, taking for the first time into account also the modelling of the forward-neutron event class required in the experimental measurements. We show that the presence of high-pT jets biases the cross section at forward dijet rapidities to be dominated by events with relatively small impact parameters between the nuclei, of the order of few nuclear radii. This leads to a sensitivity to the transverse-plane collision geometry, which we then take properly into account by including effects from the finite extent of both the photon-emitting and the target nucleus. We further discuss the potential sensitivity to the spatial dependence of nPDFs in connection to this finding.

Orateur: Petja Paakkinen (University of Jyväskylä)

Paakkinen_UPC_dijets_DIS2024.pdf

230 Dependence of two-particle azimuthal correlations on the forward rapidity gap width in pPb collisions at 8.16 TeV

The study of proton-lead events that have gaps in the rapidity distribution of final-state particles provides a unique opportunity to study colorless interactions such as pomeron-lead and photon-lead. The relative contribution of these processes depends on the size of the rapidity gap. The CMS Collaboration has previously studied the cross section of such processes as a function of the rapidity gap. This updated analysis seeks to extend such studies to the azimuthal correlations of particles produced in those events. Differential studies of the strength of these correlations will be presented as a function of the track momentum, multiplicity, and the rapidity gap.

Orateur: Moises Leon Coello (CMS, Universidad de Sonora)

DIS24 april 2024 mleoncoe.pdf

231 Di-hadron Correlations in $eA$ scattering in the CLAS experiment

Two of the questions posed by the 2023 Nuclear Science Long Range Plan are how hadrons produced in deep inelastic scattering of electrons are correlated with one another, and how the nuclear medium modifies the hadronization process. The results we present in this talk on azimuthal correlations in $\pi^+\pi^-$ and $\pi^+p$ pairs measured by the CLAS collaboration at Jefferson Lab seek to answer both of these questions. We find that the measured correlation functions peak at $\Delta\phi=\pi$ and that this peak is wider for heavier nuclei than for deuterium. We will also give predictions for similar planned measurements in a follow-up experiment with the upgraded CLAS12 detector setup, which features a higher beam energy, higher luminosity, beam polarization (which was absent in the previous measurement), and improvements in particle identification.

Orateur: Sebouh Paul (UC Riverside)

DIS talk -- di-hadrons in nuclei at CLAS (2).pdf

232 Cold Nuclear effects on azimuthal decorrelation in heavy-ion collisions

We propose to study hard processes and bulk nuclear matter on the same footing in heavy-ion collisions using Glauber modelling of heavy nuclei. To exemplify this approach, we calculate the leading-order corrections to azimuthal decorrelation in Drell-Yan and boson-jet processes due to cold nuclear effects. At leading order in both the hard momentum scale and the nuclear size, the impact-parameter dependent cross section is found to factorize for both processes. The factorization formula involves a convolution of the hard cross section with the medium-modifed initial state parton distributions, and, for the boson-jet production, the medium-modified jet function.

Orateur: Florian Cougoulic (IGFAE, University of Santiago de Compostela, Spain)

2024_04_DIS - Cougoulic.pdf

233 STUDY OF PROTON-NUCLEUS INTERACTIONS IN THE DSTAU/NA65 EXPERIMENT AT THE CERN-SPS

The DsTau (NA65) experiment at CERN was proposed to measure an inclusive differential cross-section of $D_s$ production, and its decay branching ratios in $p$-$A$ interactions. The DsTau detector is based on the nuclear emulsion technique providing an excellent spatial resolution for detecting short-lived particles like charmed hadrons. The first results of the analysis of the pilot-run data are presented. The accuracy of the proton interaction vertex reconstruction is reported. A high precision in vertex reconstruction allows one to measure the proton interaction length and charged particle multiplicities accurately in a high-track density environment. The measured data have been compared with several Monte Carlo event generators in terms of multiplicity and angular distribution of charged particles. The proton interaction length in tungsten is measured to be $106.8\pm 0.3$ mm. The predictions of KNO-G scaling are tested on the multiplicity distribution in $p$-$A$ interactions. The results presented in this study can be used to validate event generators of $p$-$A$ interactions.

Orateur: Emin Yuksel (Middle East Technical University)

DIS_v4.pdf

WG3: Electroweak Physics and Beyond the Standard Model 4

234 Lepton Flavour Universality tests using semileptonic b-hadron decays

In the SM, the electroweak bosons couple to the three lepton families with the same strength, the only difference in their behavior being due to the difference in mass. In recent years, some deviations have been found in measurements of the ratios of branching fractions for b-hadrons decaying into final states with different lepton flavours. This talk presents recent results of lepton flavour universality tests in b→cℓν decays, using hadronic or muonic τ decays, performed at LHCb.

Orateur: Chen Chen

DIS2024_SL_chenchen.pdf

235 Latest results from precision measurements at the NA62 experiment

The NA62 experiment at CERN collected the world's largest dataset of charged kaon decays in 2016-2018, leading to the first measurement of the branching ratio of the ultra-rare $K^+ \rightarrow \pi^+ \nu \bar\nu$ decay, based on 20 candidates.
In this talk NA62 reports new results from the analyses of rare kaon and pion decays, using data samples collected in 2017-2018. A sample of $K^+ \rightarrow \pi^+ \gamma \gamma$ decays was collected using a minimum-bias trigger, and the results include measurement of the branching ratio, study of the di-photon mass spectrum, and the first search for production and prompt decay of an axion-like particle with gluon coupling in the process $K^+ \rightarrow \pi^+ A$, $A \rightarrow \gamma \gamma$. A sample of $\pi^0 \rightarrow e^+ e^-$ decay candidates was collected using a dedicated scaled down di-electron trigger, and a preliminary result of the branching fraction measurement is presented. Recent results from analyses of $K^+ \rightarrow \pi^0 e^+ \nu \gamma$ and $K^+ \rightarrow \pi^+ \mu^+ \mu^-$ decays using 2017--2018 datasets are also presented. The radiative kaon decay $K^+ \rightarrow \pi^0 e^+ \nu \gamma$ (Ke3g) is studied with a data sample of O(100k) Ke3g candidates with sub-percent background contaminations. Results with the most precise measurements of the Ke3g branching ratios and T-asymmetry are presented. The $K^+ \rightarrow \pi^+ \mu^+ \mu^-$ sample comprises about 27k signal events with negligible background contamination, and the presented analysis results include the most precise determination of the branching ratio and the form factor.

Orateur: Petre Constantin Boboc

dis2024-precision_measurements_slides_boboc.pdf

236 Latest results for searches of exotic decays with NA62 in beam-dump mode

The NA62 experiment at CERN took data in 2016–2018 with the main goal of measuring the $K^+ \rightarrow \pi^+ \nu \bar\nu$ decay. In this talk we report on the search for visible decays of exotic mediators from data taken in "beam-dump" mode with the NA62 experiment. NA62 can be run as a "beam-dump" experiment by removing the kaon production target and moving the upstream collimators into a ``closed" position. In this configuration 400~GeV protons are dumped on an absorber and New Physics (NP) particles, including dark photons, dark scalars and axion-like particles, may be produced and reach a decay volume beginning 80~m downstream of the absorber. More than $10^{17}$ protons on target have been collected in "beam-dump" mode by NA62 in 2021. Recent results from analysis of this data, with a particular emphasis on Dark Photon and Axion-like particle Models, are presented. We also report new results on the first NA62 search for long-lived NP particles decaying in flight to hadronic final states based on a blind analysis of a sample of $1.4 \times 10^{17}$ protons on dump collected in 2021.

Orateur: Alina Kleimenova (EPFL)

dis2024_na62_kleimenova.pdf

237 Searches for LF/LN violation and hidden sectors in kaon decays at the NA62 experiment

Rare kaon decays are among the most sensitive probes of both heavy and light new physics beyond the Standard Model description thanks to high precision of the Standard Model predictions, availability of very large datasets, and the relatively simple decay topologies. The NA62 experiment at CERN is a multi-purpose high-intensity kaon decay experiment, and carries out a broad rare-decay and hidden-sector physics programme. Recent NA62 results on searches for violation of lepton flavour and lepton number in kaon decays, and searches for production ion hidden-sector mediators in kaon decays, are presented. Future prospects of these searches are discussed.

Orateur: Marco Ceoletta

DIS24_LNLF_Ceoletta.pdf

WG6: Joint WG1-WG6

238 Proton and nuclear structure from EIC and HERA to LHeC and FCC-eh

Orateur: Prof. Amanda Cooper-Sarkar (Oxford)

DIS2024_LHeC.pdf

239 Impact of Inclusive Electron Ion Collider Data on Collinear Parton Distributions

A study is presented of the impact of simulated inclusive Electron Ion Collider Deep Inelastic Scattering data on the determination of the proton and nuclear parton distribution functions (PDFs) at next-to-next-to-leading and next-to-leading order in QCD, respectively. The influence on the proton PDFs is evaluated relative to the HERAPDF2.0 set, which uses inclusive HERA data only, and also relative to the global fitting approach of the MSHT20 PDFs. The impact on nuclear PDFs is assessed relative to the EPPS21 global fit and is presented in terms of nuclear modification ratios. For all cases studied, significant improvements in the PDF uncertainties are observed for several parton species. The most striking impact occurs for the nuclear PDFs in general and for the region of high Bjorken x in the proton PDFs, particularly for the valence quark distributions.

Orateur: Katarzyna Wichmann (DESY)

kwichmann-pdfs-dis24.pdf

240 Extraction of the strong coupling with HERA and EIC inclusive data

Sensitivity to the strong coupling $\alpha_S(M^2_Z)$ is investigated using existing Deep Inelastic Scattering data from HERA in combination with projected future measurements from the Electron Ion Collider (EIC) in a next-to-next-to-leading order QCD analysis. A potentially world-leading level of precision is achievable when combining simulated inclusive neutral current EIC data with inclusive charged and neutral current measurements from HERA, with or without the addition of HERA inclusive jet and dijet data. The result can be obtained with substantially less than one year of projected EIC data at the lower end of the EIC centre-of-mass energy range. Some questions remain over the magnitude of uncertainties due to missing higher orders in the theoretical framework.

Orateur: Katarzyna Wichmann (DESY)

kwichmann-alphas-dis24.pdf

19:00 Conference Banquet

jeudi 11 avril

WG1: Structure Functions

241 Evolution of structure functions at NLO without PDFs

The increasingly precise experimental data from LHC have led to global extractions of parton distribution functions with significantly improved accuracy. While there are ways to approximate some theoretical uncertainties like those arising from the choices of the factorization scale, alternative approaches to tame the remaining theoretical uncertainties may eventually be needed for precision phenomenology and searches for new physics. An option advocated here is to formulate the global analysis of QCD entirely in terms of Deep Inelastic Scattering (DIS) structure functions instead of PDFs. In this talk, we show how to write down the $Q^2$ dependence of DIS structure functions at NLO with three active quark flavours, what are the novel features with respect to the leading-order case discussed in Ref. [1], and how the independence of the factorization scale and scheme arises in practice. The steps towards the first PDF-free global analysis of QCD including LHC data are outlined.

[1] T. Lappi, H. Mäntysaari, H. Paukkunen and M. Tevio, Evolution of structure functions in momentum space, Eur. Phys. J. C 84.1 (2024) [arXiv:2304.06998 [hep-ph]]

Orateur: Mirja Tevio (University of Jyväskylä)

Tevio_DIS2024.pdf

242 Towards splitting functions at four-loop order in QCD

Splitting functions, often referred to as the DGLAP evolution kernel, control the scale evolution of parton distribution functions. A highly effective approach for computing these splitting functions involves the use of off-shell operator matrix elements. Nonetheless, complications arise in the singlet sector, where physical operators become entangled with non-physical ones, giving rise to intricate challenges in the process of renormalization.

In this presentation, we systematically tackle these renormalization issues and share our most recent findings concerning specific color structures for four-loop splitting functions in Quantum Chromodynamics (QCD).

Orateur: Tongzhi Yang (University of Zurich)

DIS2024_TZY.pdf

243 Benchmarking studies at N$^3$LO.

We discuss the current staus of PDFs at NLO in perturbation theory, making comparisons with NNLO and between groups, and also summariusing the current status of the remaining uncertainty at NLO.In particular we show the result of a recent benchmarking study of PDF evolution between groups.

Orateur: Robert Thorne (University College London)

DIS2024bench.pdf

244 Full next-to-leading order QED contribution to lepton-hadron scattering in a joint QED and QCD factorization approach

With a large momentum transfer, high energy lepton-hadron scattering induces both QED and QCD radiations. Contribution of induced QCD radiation to scattering cross sections has been consistently evaluated in terms of QCD factorization approach, while contribution from induced QED radiation has been historically corrected by imposing a “radiative correction factor” to the lowest order (LO) cross section in QED coupling. The “correction” for the simple inclusive deep inelastic scattering (DIS) cross section could be as large as the value of LO cross section to be corrected in some kinematic regime. For observables with more final-state particles, e.g., semi-inclusive DIS, the single “correction” factor cannot account for full impact of QED radiation to the rich structure of the final-state. Recently, a joint QED and QCD factorization approach to evaluate high energy lepton-hadron scattering cross section was proposed to treat both QED and QCD induced radiation equally [1,2]. In this talk, we will present the first calculation of next-to-leading order (NLO) QED contributions to the factorized short-distance hard scattering coefficients to clearly demonstrate how the joint factorization consistently factorize all perturbative collinear sensitivities of partonic scattering into corresponding universal lepton and hadron distributions without the need of any parameters other than the standard factorization scale. We also discuss the impact of this joint factorization approach on the precision of parity-violating DIS and its reach for physics beyond the standard model.

[1] T. Liu, W. Melnitchouk, J.W. Qiu and N. Sato,
“A new approach to semi-inclusive deep-inelastic scattering with QED and QCD factorization,'' JHEP 11, 157 (2021) [arXiv:2108.13371 [hep-ph]].

[2] T. Liu, W. Melnitchouk, J.W. Qiu and N. Sato,
“Factorized approach to radiative corrections for inelastic lepton-hadron collisions,'' Phys. Rev. D104, 094033 (2021) [arXiv:2008.02895 [hep-ph]].

Orateurs: Dr Jianwei Qiu (Jefferson Lab), Dr Jia-Yue Zhang (Jefferson Lab)

DIS_WG1_Qiu.pdf

245 Recent Progress in Transverse Momentum-Dependent Parton Densities and Corresponding Parton Showers

The Parton Branching (PB) method outlines the evolution of transverse momentum-dependent (TMD) parton distributions across various kinematic regions, ranging from small to large transverse momenta $k_T$. In the small $k_T$ region, the PB method is highly sensitive to both the intrinsic motion of partons (intrinsic $k_T$) and the resummation of soft gluons, as described by the PB TMD evolution equations. The PB method is employed to investigate the role of soft (non-perturbative) gluon emissions in TMD, along with integrated collinear parton densities. Notably, soft gluons make a significant contribution to collinear parton densities. Within the PB framework, the Sudakov form factor is divided into perturbative and non-perturbative components. Analytical calculation of the non-perturbative part is feasible under specific conditions. The inclusion of soft (non-perturbative) gluons in parton density evolution is crucial for effectively canceling divergent terms.

It is suggested that the non-perturbative part of the Sudakov form factor has its correspondence in TMD parton distributions. In the PB approach, this non-perturbative Sudakov form factor is constrained through fits of inclusive, collinear parton densities. A detailed examination of the PB TMD methodology at next-to-leading order (NLO) in Drell-Yan (DY) production for low transverse momenta is presented. The extraction of intrinsic $k_T$ is showcased, demonstrating minimal dependence on DY mass and center-of-mass energy. This contrasts with tuned standard Monte Carlo event generators, which typically exhibit a strong increase in intrinsic Gauss width with center-of-mass energy.

Orateur: Dr Sara Taheri Monfared (DESY)

RecentPBDevelopment-SaraTaheriMonfared-DIS2024-V2.pdf

10:30 Coffee break

WG4: QCD with Heavy Flavours and Hadronic Final States 5

246 Extensions of MadGraph5 aMC@NLO for QCD studies

In this talk, I will present our extensions of MadGraph5_aMC@NLO for two asymmetric systems, photoproduction and proton-nucleus collisions as well as progress towards automation of computations for inclusive-quarkonium production, currently being worked out at leading order.

Indeed, to consolidate the figures of merit of a variety of measurements at the Electron-Ion Collider and systematise data-theory comparisons at the LHC, it is essential to include radiative corrections in simulations of electron-proton, electron-nucleus and proton-nucleus collisions. Such an automation is currently achieved at NLO in the fixed-order mode within MadGraph5_aMC@NLO.

Extensive validations for hard reactions, like charm, beauty, Drell-Yan-pair, $Z$ and $W$ boson production, will be shown as well as predictions for future measurements.

Orateur: Laboni Manna (Warsaw University of Technology)

DIS_2024_LM.pdf

247 The azimuthal correlation between the leading jet and the scattered lepton in deep inelastic scattering at HERA

The azimuthal correlation angle, $\Delta\phi$, between the scattered lepton and the leading jet in deep inelastic $ep$ scattering at HERA has been studied using HERA II data collected with the ZEUS detector. The data set features $e^{\pm}p$ collisions at a centre-of-mass energy of $\sqrt{s} = 318$ GeV, corresponding to an integrated luminosity of 326 pb$^{-1}$. A measurement of jet cross sections was performed within the fiducial region, specified in the laboratory frame, of the photon virtuality 10 GeV$^2 < Q^2 < 350$ GeV$^2$, inelasticity $0.04 < y < 0.7$, outgoing lepton energy $E_e > 10$ GeV, lepton polar angle $140^o < \theta_e < 180^o$, jet transverse momentum 2.5 GeV < $p_\mathrm{T,jet} < 30$ GeV, and jet pseudorapidity $-1.5 < \eta_\mathrm{jet} < 1.8$. Jets were reconstructed using the $k_\mathrm{T}$ algorithm with the radius parameter $R = 1$. Leading jets are defined as jets that carry the highest $p_\mathrm{T,jet}$. Differential cross sections, $d\sigma/d\Delta\phi$, will are presented as a function of the azimuthal correlation angle in various $p_\mathrm{T,jet}$, $Q^2$ and jet-multiplicity ranges. Perturbative calculations at $\mathcal{O}(\alpha_{s}^2)$ accuracy successfully describe the data within the fiducial region, while a lower level of agreement is observed near $\Delta\phi \rightarrow \pi$ for events with high jet-multiplicity due to limitations of the perturbative approach in describing soft QCD phenomena. Monte Carlo predictions that supplement leading-order matrix elements with parton showering describe the data as well as the $\mathcal{O}(\alpha_{s}^2)$ calculations do.

Orateur: Jae Nam (Temple University)

Nam_20240411_v2.pdf

248 Multi-Jet Merging in Deep Inelastic Scattering with Pythia

In the era of the upcoming Electron-Ion Collider (EIC), the importance of accurate modeling of deep inelastic scattering (DIS) events is ever increasing. We aim to improve the modeling of DIS by implementing multi-jet merging capabilities in Pythia, the most widely-used Monte Carlo (MC) event generator among the LHC experiments. Multi-jet merging allows the combination of parton shower algorithms with fixed-order perturbation theory. This approach combines the accurate modeling of logarithmically enhanced emissions in parton showers with hard jets described by QCD matrix elements. A key challenge in this procedure is to avoid double-counting of different event classes. Multi-jet merging algorithms have successfully been implemented for LHC-processes in many MC event generators. For DIS processes, merging algorithms are currently only available in the Sherpa MC generator, where they found significant contribution to jet cross sections from high-multiplicity events.

In our current project we have implemented DIS multi-jet merging in the Vincia parton shower algorithm in Pythia using hard scattering events generated with MadGraph5 and Sherpa. In this talk, we summarise the implementation of jet merging and compare the results of two different merging algorithms, CKKW-L and UMEPS, with experimental HERA data provided by H1 and ZEUS collaborations. We show that multi-jet merging is necessary for an accurate description of DIS jets in a wide range of photon virtuality $Q^2$. We quantify systematic uncertainties by varying the factorization, renormalization and jet merging scales.

Orateur: Joni Laulainen (University of Jyväskylä)

MultiJetMerging_Laulainen-2.pdf

249 Observation of events with an empty hemisphere in the Breit frame and differential cross section measurement

The Breit frame provides a natural reference frame to analyze lepton-proton (ep) scattering events when the process of interest is plainly considered as a photon-hadron interaction. In the Breit frame, the photon runs on the z axis into the positive direction, and in the leading order picture the struck quark leaves the interaction on the z axis, too. Higher-order QCD corrections change that picture and at suffciently low x, a rather spectacular event signature is predicted with no radiation in the forward direction but all emissions are expected to be found in the backward direction, from where the photon approaches. We report on a first observation of those empty current hemisphere events in electron-proton collisions at the HERA collider using data recorded with the H1 detector at a center-of-mass energy of 319 GeV. The large data sample corresponds to an integrated luminosity 351.1 pb$^{-1}$ and allows for a differential cross section measurement of these events. The data are compared to selected predictions from Monte Carlo event generators.

Orateur: Zhiqing Zhang (IJCLAB Orsay)

Zhang_DIS24-2.pdf

250 A POWHEG generator for DIS

We present a new event generator for the simulation of both neutral- and charged-current DIS at NLO QCD matched to parton showers using the POWHEG method. Our implementation builds on the existing POWHEG BOX framework originally designed for hadron-hadron collisions, supplemented by considerable extensions to account for the genuinely different kinematics inherent to lepton-hadron collisions. We compare our predictions to fixed-order and resummed predictions, as well as to data from the HERA ep collider. Finally we study a few representative distributions for the upcoming Electron Ion Collider.

Orateur: Andrea Banfi (University of Sussex)

banfi_DIS24.pdf

10:30 Coffee break

WG5: Spin and 3D Structure 5

251 CLAS12 SIDIS Program Overview

A series of completed, ongoing, and proposed Semi Inclusive Deep Inelastic Scattering (SIDIS) experiments using the CLAS12 spectrometer in Hall B at Jefferson Lab are reviewed. These studies consist of scattering data from a highly polarized 11 GeV electron beam incident on a fixed proton/deuteron target which, in the case of the recently completed Run Group C experiment, were longitudinally polarized. In this presentation, we overview the CLAS12 detector system as whole, followed by discussions of the theoretical motivation for the corresponding SIDIS studies and their current state of progress/publication.

Orateur: Gregory Matousek (Duke University)

CLAS12 SIDIS Program Overview (DIS 2024) v2.pdf

252 Measurement of azimuthal modulations in SIDIS off proton target at COMPASS

The azimuthal angle distribution ($\phi_h$) of hadrons produced in deep inelastic scattering serves as a powerful tool for probing nucleon structure in terms of the transverse momentum-dependent parton distribution functions, and the fragmentation functions. For an unpolarized nucleon, three azimuthal modulations arise: $\cos \phi_h$ related to the Cahn effect, $\cos 2\phi_h$ linked to the Boer-Mulders function, and $\sin \phi_h$ known as beam-spin asymmetry, each revealing insights into combinations of twist-two or higher-twist distribution and fragmentation functions.

The COMPASS collaboration at CERN collected tens of millions of semi-inclusive deep inelastic scattering events across 2016 and 2017 using a longitudinally polarized 160 GeV/c muon beam scattering off a liquid hydrogen target. The data from 2016 corresponding to about 1/3 of the full sample have been analyzed to measure the azimuthal modulations of charged hadrons. Results were corrected for QED radiative effects using DJANGOH MC generator.

Orateur: Vendula Benešová

DIS_2024_Benesova.pdf

253 Non-perturbative Collins-Soper kernel: Chiral quarks and Coulomb-gauge-fixed quasi-TMD

We present the first lattice QCD calculation of the rapidity anomalous dimension of transverse-momentum-dependent distributions (TMDs), i.e. the Collins-Soper (CS) kernel, employing the recently proposed Coulomb-gauge-fixed quasi-TMD formalism as well as a chiral-symmetry-preserving lattice discretization.

This unitary lattice calculation is conducted using the domain wall fermion discretization scheme, a fine lattice spacing of approximately 0.08 fm, and physical values light and strange quark masses. The CS kernel is determined analyzing the ratios of pion quasi-TMD wave functions (quasi-TMDWFs) at next-to-leading logarithmic (NLL) perturbative accuracy.

Thanks to the absence of Wilson lines, The Coulomb-gauge-fixed quasi-TMDWF demonstrates a remarkably slower decay of signals with increasing quark separations. This allows us to access non-perturbative CS kernel up to transverse separations 1 fm. For small transverse separations agree well with the perturbative predictions. At transverse separations our non-perturbative CS kernel clearly favors certain global fits.

Orateur: Swagato Mukherjee (Brookhaven National Laboratory)

Mukherjee.pdf

254 Studying hadronization at LHCb

The Large Hadron Collider beauty (LHCb) experiment provides an opportunity to study hadronization processes, how particular hadrons are formed from scattered quarks and gluons (partons), in the forward region, 2 < η < 5. Going beyond traditional collinear non-perturbative fragmentation functions (FFs), transverse-momentum-dependent (TMD) FFs provide multidimensional information on the hadronization process. The excellent hadron identification capabilities of LHCb allow for a wealth of possible hadronization measurements. Ongoing and prospective measurements of TMD hadronization in heavy-flavor-tagged jets as well as the polarization of inclusively produced Λ and Λ-bar in heavy-ion pPb and fixed-target pNe will be discussed.

Orateur: Cynthia Nunez (Ann Arbor-University of Michigan)

CNunez_DIS_WG5_Apr11.pdf

255 Unlocking Higher-Order Moments of parton distribution functions from lattice QCD

We describe a novel procedure to determine moments of parton distribution functions of any order with lattice QCD computations. The procedure is based on the gradient flow for fermion and gauge fields. The flowed matrix elements of twist-2 operators renormalize multiplicatively, and the matching with physical matrix elements is obtained making use of continuum symmetries. We calculate the matching coefficients at one-loop in perturbation theory for moments of any order in the flavor non-singlet case, and give specific examples of operators that could be used in lattice QCD computations. The multiplicative renormalization and matching is independent on the choice of Lorentz indices, thus permitting the utilization of temporal indices for twist-2 operators of any dimension. This should substantially improve the signal-to-noise ratio in the computation of the moments.

Orateur: Dr Andrea Shindler (RWTH - Aachen University)

shindler_mom.pdf

10:40 Coffee Break

WG3: Electroweak Physics and Beyond the Standard Model 5

256 Observing true tauonium at colliders

The bound state of two tau leptons, ditauonium $\mathcal{T}$, is the heaviest and also most compact QED atom, and remains unobserved to date. There are several motivations for its study such as precisely extracting properties of the tau lepton, carrying out novel tests of SM and its basic CPT symmetries, and searching for BSM effects impacting the tau lepton. We will first discuss the spectroscopic properties of ditauonium, including energy levels and decay channels. A systematic survey of search strategies at present and future lepton and hadron colliders will then be provided. The spin-triplet state, ortho-ditauonium, can be observed at a future super tau-charm factory (STCF) via $e^+e^-\to\mathcal{T}_1\to\mu^+\mu^-$, where a threshold scan with monochromatized beams can also provide a very precise extraction of the tau lepton mass with $\mathcal{O}(25$ keV) uncertainty. Observing pp $\to \mathcal{T}_1(\mu^+\mu^-)+X$ is possible at the LHC by identifying its displaced vertex with a good control of the combinatorial dimuon background. The spin-singlet state, para-ditauonium, will be observable in photon-photon collisions at the FCC-ee via $\gamma\gamma\to\mathcal{T}_0\to\gamma\gamma$.

Orateur: David d'Enterria (CERN)

dde_ditauonium_dis24_apr2024.pdf

257 ATLAS Searches with Unconventional Signatures

Many theories beyond the Standard Model (SM) have been proposed to address several of the SM shortcomings. Some of these beyond-the-SM extensions predict new particles or interactions directly accessible at the LHC, but which would leave unconventional signatures in the ATLAS detector. These unconventional signatures require special techniques and reconstruction algorithms to be developed, enabling analysers to perform unique searches for new physics. This talk will cover several such searches using the Run-2 dataset.

Orateur: Martina Ressegotti

DIS2024_ATLASsearchesUnconventionalSignatures.pdf

258 SM and BSM physics with photon-photon collisions at the LHC

The LHC is not only the energy-frontier collider for parton-parton collisions, but it has proven to work as a powerful photon collider providing photon-photon collisions at center-of-mass energies never reached before. I will present results of the gamma-UPC Monte Carlo event generator [1] that can calculate any arbitrary exclusive final states produced via photon fusion in ultraperipheral collisions of protons and/or nuclei at the LHC, of relevance for novel SM measurements and BSM searches. The latest gamma-UPC developments and comparisons to LHC data will be presented [2].

[1] H.-S. Shao and D. d'Enterria, JHEP 09 (2022) 248
[2] Nicolas Crepet, David d'Enterria, Hua-Sheng Shao, in preparation

Orateur: Nicolas Crépet (CERN)

slides_DISGrenoble2024v3_NicolasCrépet.pdf

259 Results from muon reconstruction performance with the ATLAS experiment at the LHC using Run-3 proton-proton collision data

Muon reconstruction performance plays a crucial role in the precision and sensitivity of the Large Hadron Collider (LHC) data analysis of the ATLAS experiment. Accurately measuring the muon performance of the ATLAS detector is of paramount importance to provide fundamental input to physics analyses involving muons. Furthermore, the ATLAS Muon Spectrometer was significantly upgraded for LHC Run-3, most notably with the New Small Wheel upgrade project, including new muon detectors with innovative design; measuring the performance of this upgrade on real data is therefore extremely important. Using di-muon resonances we are able to characterize and calibrate with high accuracy the detector response for muons in terms of muon identification and isolation efficiency and muon momentum measurement. An overview of the state-of-the-art methods for muon performance measurement and on the results obtained on Run-3 proton-proton collision data at a center-of.mass energy of 13.6 TeV is presented here.

Orateur: Davide Cieri

240411_MCP_DIS2024.pdf

260 Recent results from Belle II

The Belle II experiment has collected a 424 fb$^{-1}$ data set of $e^+e^-$ collisions produced by the asymmetric-energy SuperKEKB collider. Three-quarters of the data have a centre-of-mass energy equal to the mass of the $\Upsilon(4S)$ resonance, which decays to $B$-meson pairs, allowing measurements of rare $B$ decays, $C\!P$ violation, and searches for lepton universality violation. Highlights include the first observation of $B\to K\nu\bar{\nu}$ and measurements of lepton-universality in semitauonic $B$ decays. We have also recorded a dedicated 19.2$~$fb$^{-1}$ data set away from the $\Upsilon(4S)$, where we have made measurements related to the properties of the $\Upsilon(10753)$, to probe its potentially exotic nature. Our first results related to charm hadron decays, which use the full data sample, are also presented.

Orateur: Youngjoon Kwon (Yonsei University)

DIS2024_Belle-II_Kwon.pdf

WG6: Future Experiments 5

261 Strong Interaction Physics at the Luminosity Frontier with 22 GeV Electrons at Jefferson Lab

The initial scientific case for upgrading the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab (JLab) to 22 GeV will be presented. The proposed physics program encompasses a large and diverse range of transforamtive investigations centered around the non-perturbative dynamics inherent in hadron structure and the exploration of strongly interacting systems. It builds upon the unique capabilities of CEBAF high-luminosity operations, the availability of existing or planned Hall equipment, and recent advancements in accelerator technology. Highlights and some key measurements will be discussed, with emphasis on the significant physics outcomes and unique aspects of these programs that distinguish them from other existing or planned facilities.

Orateur: Cynthia Keppel (Thomas Jefferson National Accelerator Facility)

DIS2024_Keppel.pptx

262 Jefferson Lab's Planned Positron Physics Program

Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) has been delivering high polarization and high current electron beams for fixed target nuclear physics experiment for more than two decades. Plans are now being developed to use the CEBAF accelerator for providing highly polarized positrons to the experimental halls. This work builds on the successful Polarized Electrons for Polarized Positrons (PEPPo) project which demonstrated the possibility of using polarized electrons for making a polarized positron source. In this talk will give an overview of the planned polarized positron source as well as an overview of the science that has been proposed to be done with this upgrade to the Jefferson Lab accelerator.

Orateur: Holly Szumila-Vance (Jefferson Lab)

DIS2024_positrons.pdf

263 Status of the Ce+BAF upgrade

Jefferson Lab is proposing to add positron beams to the 12 GeV Continuous Electron Beam Accelerator Facility (CEBAF). A team of accelerator, physics and engineering staff have been developing the concept for the generation, production and delivery of Continuous (CW) polarized positron beams to the experimental halls, up to the full 12 GeV. A layout of the proposed concept will be shown. We will report on the ongoing efforts in the positron generation and capture, target design, beam transport and expected properties of the e+ beam on the experimental targets at 12GeV.

This project is supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177

Orateur: Yves Roblin (Jefferson Lab)

DIS2024Ce+BAF.pdf

264 The NuPECC Long Range Plan 2024

I will illustrate the agenda of the preparation of the NuPECC LRP. Then, I will highlight some (temporary) outcomes that regard physics and facilities where Deep-Inelastic Scattering in involved.

Orateur: Carlos Munoz Camacho (IJCLab, CNRS/IN2P3)

DIS2024_NuPECC.pdf

265 The LHeC and FCC-eh experimental program +A detector for future DIS at the energy frontier

Leveraging the novel concept of Energy Recovery Linacs (ERL), we present the LHeC and FCC-eh colliders that allow the exploration of electron-hadron interactions above the TeV scale. The presented design of the electron accelerator is based on two superconducting linear accelerators in a racetrack configuration that can produce lepton beam energies in excess of 50 GeV. In energy recovery mode, where the beam energy of the colliding beam is recovered for the acceleration of the next beams of particles, the accelerator is capable of reaching luminosities in excess of $10^34$ cm$^{-2}$s$^{-1}$ with an energy footprint of around 100 MW for the electron accelerator. The proposed collider concept enables luminosity values high enough for a general-purpose experimental program. While the envisaged physics results have the potential to empower the HL-LHC or FCC-hh physics results, they also include flagship EW, Higgs, QCD and top quark measurements beyond current precision,and complementary searches Beyond Standard Model. New thematic ep/eA@CERN working groups are established and synergistic efforts are pursued with the HL-LHC and the EIC programs.

The proposed Large Hadron-electron Collider and the Future Circular Collider in electron-hadron mode will make possible the study of DIS in the TeV regime. These facilities will provide electron-proton (nucleus) collisions with per nucleon instantaneous luminosities around $10^{34}$($10^{33}$) cm$^{−2}$s$^{−1}$ by colliding a 50-60 GeV electron beam from a highly innovative energy-recovery linac system with the LHC/FCC hadron beams, concurrently with other experiments for hadron-hadron collisions. The detector design was updated in the 2020 Conceptual Design Report. Ongoing developments since then include an improved interaction region design, reflecting state-of-the-art synchrotron radiation simulations, together with a more detailed study of an all-silicon central tracking detector. Additional capabilities for particle identification, enabling improved semi-inclusive DIS and eA studies, are also under study. In this talk, we describe the current detector design and ongoing discussion in the framework of a new ep/eA study being carried out on behalf of CERN, highlighting areas of common interest with other future collider experiments and the new Detector R&D Collaborations in Europe.

Orateur: Paul Newman (University of Birmingham)

LHeC-DIS24.v1.0.pdf

10:40 Coffee Break

WG2: Small-x, Diffraction and Vector Mesons 5

266 Non-eikonal effects in dijet production at the Electron-Ion Collider

Orateur: Pedro Agostini (NCBJ and IGFAE)

Agostini_DIS2024.pdf

267 Power corrections to back-to-back DIS dijets: Next-to-Eikonal versus twist 3

Orateurs: Guillaume Beuf, Guillaume Beuf (National Centre for Nuclear Research (NCBJ), Warsaw), Guillaume Beuf (National Centre for Nuclear Research (NCBJ), Warsaw, Poland)

GBeuf_DIS_2024.pdf

268 Leading-Twist Quark TMDs at Small-x

Orateur: M Gabriel Santiago (SURA Center for Nuclear Femtography)

DIS_2024_smallx_santiago.pdf

269 t-channel quark exchange in SIDIS and inclusive DIS at small-x beyond eikonal approximation

Orateur: Swaleha Mulani (National Centre for Nuclear Research (NCBJ), Warsaw, Poland)

DIS24 _Swaleha.pdf

10:30 Coffee break

Plenary: 5

Président de session: Zein-Eddine Meziani (Argonne National Laboratory)

270 Status of the muon g-2

Orateur: Antoine Gerardin

gerardin_DIS.pdf

271 Strong CP problem in QCD and Axions

Orateur: Christopher Smith (LPSC)

DIS_smith.pdf

272 Status of nEDM measurements

Orateur: Skyler Degenkolb

20240411_DIS2024_SMD.pdf

12:30 Lunch

14:00 Excursion

vendredi 12 avril

Plenary: 6

Président de session: Dr Mariane Mangin-Brinet (CNRS/L.P.S.C.)

273 PDFs on the lattice

Orateur: Huey-Wen Lin (Michigan State University)

hwlin_DIS24-talk.v2.pdf

274 QCD and Quantum Computing

Orateur: Christian Bauer

CBauerPlenary.pdf

275 50 years of J/Psi discovery

Orateur: Jean Iliopoulos (Ecole Normale Supérieure)

Grenoble-onJPsi-2024.pdf

Ingo_Mariane_ JeanIliopoulos _Johann.jpg

10:30 Coffee break

Plenary: 7

Président de session: Valerio Bertone (CEA Paris-Saclay)

276 WG1 Summary

Orateurs: Francesco Giuli (CERN), Aleksander Kusina (Institute of Nuclear Physics PAN, Krakow), Emanuele Roberto Nocera (Università di Torino and INFN Torino)

WG1 summary talk-1.pdf

277 WG2 Summary

Orateurs: Cristian Baldenegro (Sapienza Università di Roma (IT)), Renaud Boussarie (CPHT, CNRS, Ecole polytechnique, IP Paris), Pieter Taels (University of Antwerp)

WG2 summary.pdf

278 WG3 Summary

Orateurs: Sezen Sekmen (Kyungpook National University), Eleni Vryonidou

wg3summary.pdf

12:30 Lunch

Plenary: 8

Président de session: Abhay Deshpande

279 WG4 Summary

Orateurs: Ilkka Helenius (University of Jyväskylä), Laure Massacrier (IJCLab), Giovanni Stagnitto

WG4 Summary.pdf

280 WG5 Summary

Orateurs: Julie Roche (Ohio University), Prof. Qinghua Xu (Shandong University), Savvas Zafeiropoulos (LPC-CNRS)

WG5_summary_2024.pdf

281 WG6 Summary

Orateurs: Alessandro Tricoli (Brookhaven National Laboratory), Leticia Cunqueiro (Rome Sapienza University), Wenliang Li (CFNS, Stony Book University)

DIS2024_WG6_Summary.pdf

Plenary: Pleanry 9

Président de session: Abhay Deshpande

282 The next QCD Frontiers with the EIC

Orateur: Christine Aidala (University of Michigan)

AidalaDIS2024EIC.pdf

283 Report from the IAC

Orateur: Paul Newman

IAC-report-2024.v2.pdf

284 Closing Remarks

Orateur: ingo Schienbein (LPSC)

Closing_DIS2024.pdf