CHEX-MATE: AMALGAM weak-lensing analysis of 41 Planck Sunyaev--Zel'dovich-selected galaxy clusters

Abstract

We present a weak-lensing shear analysis of 41 =3.53 Sunyaev--Zel'dovich (SZ)-selected galaxy clusters at 0.11 łe z łe 0.55 from the CHEX-MATE sample, using wide-field Subaru/Suprime-Cam and CFHT/MegaPrime imaging from the project. The azimuthally averaged weak-lensing signal, measured around the X-ray peak of each cluster, has a median signal-to-noise ratio of 6.5 per cluster. The 45^̧irc-rotated component has a median signal-to-noise ratio of -0.1 and ranges from -1.8 to $+1.8$, consistent with zero. We modelled the excess surface mass density profile of each cluster with a Navarro--Frenk--White profile to infer the weak-lensing mass and concentration constraints. The estimated total systematic uncertainty in the weak-lensing mass calibration is 8 =10^ Using a hierarchical Bayesian framework, we then derived weak-lensing-calibrated scaling relations for the halo concentration, c_200, as a function of M_200 and redshift, and for the SZ mass proxy, Msz, as a function of M_500 and redshift. In both regressions, we modelled the latent true-mass distribution of the selected sample and accounted for weak-lensing modelling biases and residual calibration uncertainty. For the Msz--M_500--z relation, we also included an effective treatment of the CHEX-MATE tier selection. At the pivot mass M_ 200 15 and redshift z=0.25, we find c_ 200 with an intrinsic scatter of 0.22 =0.83 =7 dex. The inferred normalisation and scatter are consistent with recent predictions for massive haloes, with no significant mass or redshift dependence over the probed range. For the mass proxy, our baseline regression yields Msz/M_ 500 at M_ 500 14 and z=0.25, with an intrinsic scatter of 0.10 dex. A restricted model with the mass slope fixed to unity and no redshift evolution yields 1- We also provide weak-lensing-calibrated posterior estimates of M_500 for the sample based on the baseline Msz--M_500--z relation. These results provide an initial weak-lensing mass calibration for CHEX-MATE multi-probe cluster studies.