Multi-probe analysis of the galaxy cluster CL J1226.9+3332: Hydrostatic mass and hydrostatic-to-lensing bias

TL;DR

This study combines multi-instrument observations to accurately estimate the hydrostatic mass of galaxy cluster CL J1226.9+3332 at high redshift and assesses the bias between hydrostatic and lensing mass estimates, crucial for cosmology.

Contribution

It provides a comprehensive analysis of hydrostatic mass estimation for a high-redshift galaxy cluster using multiple data sets and evaluates the hydrostatic-to-lensing mass bias.

Findings

Hydrostatic mass estimates are robust and agree with literature.

Mass profile shape differences significantly affect R500 mass calculations.

Hydrostatic-to-lensing bias ranges from 0.7 to 1, influenced by data and models.

Abstract

The precise estimation of the mass of galaxy clusters is a major issue for cosmology. Large galaxy cluster surveys rely on scaling laws that relate cluster observables to their masses. From the high resolution observations of ~ 45 galaxy clusters with NIKA2 and XMM-Newton instruments, the NIKA2 SZ Large Program should provide an accurate scaling relation between the thermal Sunyaev-Zel'dovich effect and the hydrostatic mass. In this paper, we present an exhaustive analysis of the hydrostatic mass of the well known galaxy cluster CL J1226.9+3332, the highest-redshift cluster in the NIKA2 SZ Large Program at z = 0.89. We combine the NIKA2 observations with thermal Sunyaev-Zel'dovich data from NIKA, Bolocam and MUSTANG instruments and XMM-Newton X-ray observations and test the impact of the systematic effects on the mass reconstruction. We conclude that slight differences in the shape of the mass profile can be crucial when defining the integrated mass at R500, which demonstrates the importance of the modeling in the mass determination. We prove the robustness of our hydrostatic mass estimates by showing the agreement with all the results found in the literature. Another key information for cosmology is the bias of the masses estimated assuming hydrostatic equilibrium hypothesis. Based on the lensing convergence maps from the Cluster Lensing And Supernova survey with Hubble (CLASH) data, we obtain the lensing mass estimate for CL J1226.9+3332. From this we are able to measure the hydrostatic-to-lensing mass bias for this cluster, that spans from 1 - bHSE/lens ~ 0.7 to 1, presenting the impact of data-sets and mass reconstruction models on the bias.