31st International Workshop on Deep Inelastic Scattering

Transverse-spin asymmetries in COMPASS Drell-Yan data

10 avr. 2024, 14:30

20m

Maison MINATEC, Grenoble, FRANCE

Regular parallel talk WG5: Spin and 3D Structure WG5

Orateur

Małgorzata Niemiec (University of Warsaw)

Description

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 $\to {\mu }^{+}{\mu }^{-}$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 $k_{\mathrm{T}}^2$ moments. Results of these analyses together with a comparison with results obtained in the semi-inclusive muon production will be presented.

Documents de présentation

MNiemiec_DIS2024.pdf