Présidents de session
Thursday P1
- Marco De Petris (Sapienza, University of Rome)
Thursday P1
- Sebastian Bocquet (LMU Munich)
An accurate mass calibration of galaxy clusters is a crucial step towards precise constraints on the cosmological parameters $\sigma_8$ and $\Omega_m$ from clusters. In the millimeter, via the Sunyaev-Zel'dovich (SZ) effect, and X-rays domains, cluster masses can be estimated assuming hydrostatic equilibrium, but several physical and observational effects can alter this calculation. One of...
I will present a nodal approach to recovering the fundamental properties of galaxy clusters like pressure, density, and temperature. The method involves constructing piecewise functions that describe the quantities of galaxy clusters through a set of control points, which are inferred using a non-parametric Bayesian analysis. I will show an application of this method to the analysis of Planck...
The total mass of a cluster is one of its most fundamental properties. Measurements of the galaxy cluster mass often relies upon assuming hydrostatic equilibrium. However, this is often invalidated as the intracluster medium (ICM) is continuously disturbed by mergers, feedback processes, and motions of galaxies. These processes generate gas motions that contribute nonthermal pressure;...
The Zernike polynomials has been recently used to model 2D projection maps of galaxy clusters to recover their morphological features. The study of the morphology of clusters maps is, in fact, a well suited approach used to infer, from real data, the dynamical state of those systems. After the validation of the Zernike polynomials as suitable tools to constrain galaxy clusters morphologies,...
Weak gravitational lensing is a powerful tool to probe the matter distribution around massive galaxy clusters. In general, such effect can be measured by estimating the averaged tangential shear of background galaxies in circular annuli around the lens center. In addition to the average tangential shear, valuable information on the underlying dark matter distribution can be extracted by using...
Accurate reconstruction of galaxy cluster masses is key to use this population of objects as cosmological probe. In this work we present a study on the hydrostatic to lensing mass scaling relation for a sample of 53 clusters, with redshifts from z = 0.05 to 1.07, for which masses have been reconstructed homogeneously. Masses for each individual cluster have been measured from reconstructed...
We present a detailed study of the surface brightness profiles derived from a representative sample of 118 clusters selected via the Sunyaev-Zel'Dovich effect. These profiles represent an ideal tool to investigate the properties of the hot plasma filling the cluster volume. Studies of these profiles have been hampered by selection biases and faintness of the emission in the outskirts. We...