NIKA2 observations of 3 low-mass galaxy clusters at $z \sim 1$: pressure profile and $Y_{\rm SZ}$-$M$ relation

TL;DR

This study uses NIKA2 observations to analyze the pressure profiles and SZ flux-mass relation of three low-mass, high-redshift galaxy clusters, revealing that standard cluster physics is established by z~1 despite their dynamical activity.

Contribution

First measurement of pressure profiles and SZ flux-mass relation for low-mass, high-redshift clusters using NIKA2, confirming standard cluster physics at z~1.

Findings

Clusters follow expected pressure profiles despite disturbances.

SZ flux-mass relation aligns with standard evolution models.

Clusters exhibit signs of merging activity.

Abstract

Three galaxy clusters selected from the XXL X-ray survey at high redshift and low mass ($z\sim1$ and $M_{500} \sim 1-2 \times 10^{14}$ M$_{\odot}$) were observed with NIKA2 to image their Sunyaev-Zel'dovich effect (SZ) signal. They all present an SZ morphology, together with the comparison with X-ray and optical data, that indicates dynamical activity related to merging events. Despite their disturbed intracluster medium, their high redshifts, and their low masses, the three clusters follow remarkably well the pressure profile and the SZ flux-mass relation expected from standard evolution. This suggests that the physics that drives cluster formation is already in place at $z \sim 1$ down to $M_{500} \sim 10^{14}$ M$_{\odot}$.