Reconstructing three-dimensional parameters of galaxy clusters via multifrequency SZ observations

TL;DR

This paper introduces a non-parametric method to reconstruct three-dimensional physical properties of galaxy clusters solely from multifrequency SZ observations, enabling detailed ICM analysis without relying on X-ray data.

Contribution

The work develops and tests a new non-parametric approach for deriving 3D cluster parameters from SZ data alone, including systematic uncertainty assessment.

Findings

Accurate 3D ICM profiles can be reconstructed from simulated SZ data.

Method effectively accounts for instrumental and astrophysical uncertainties.

Enables detailed cluster analysis without X-ray follow-up.

Abstract

The Sunyaev-Zeldovich (SZ) effect is a promising tool to study physical properties of the hot X-ray emitting intracluster medium (ICM) in galaxy clusters. To date, most SZ observations have been interpreted in combination with X-ray follow-up measurements in order to determine the ICM temperature and estimate the cluster mass. Future high-resolution, multifrequency SZ observations promise to enable detailed studies of the ICM structures, by measuring the ICM temperature through the temperature-dependent relativistic corrections. In this work we develop a non-parametric method to derive three-dimensional physical quantities, including temperature, pressure, total mass, and peculiar velocities, of galaxy clusters from SZ observations alone. We test the performance of this method using hydrodynamical simulations of galaxy clusters, in order to assess systematic uncertainties in the reconstructed physical parameters. In particular, we analyze mock Cerro Chajnantor Atacama Telescope (CCAT) SZ observations, taking into account various sources of systematic uncertainties associated with instrumental effects and astrophysical foregrounds. We show that our method enables accurate reconstruction of the three-dimensional ICM profiles, while retaining full information about the gas distribution. We discuss the application of this technique for ongoing and future multifrequency SZ observations.