The cosmic microwave background spectral modification due to thermal Comptonization in galaxy clusters. Analytical consideration

TL;DR

This paper presents an analytical method to estimate how thermal Comptonization in galaxy clusters deforms the cosmic microwave background spectrum, enabling determination of cluster properties from CMB observations.

Contribution

It introduces a new analytical approach to quantify CMB spectral modifications caused by thermal Comptonization in galaxy clusters.

Findings

Analytical estimation of CMB spectral deformation due to Comptonization.

Method to determine optical depth and electron temperature of clusters from CMB data.

Potential for improved galaxy cluster characterization using CMB spectral analysis.

Abstract

See comments. We calculate analytically an effect of the thermal Comptonization on the cosmic microwave background (CMB) photons when they propagate through galaxy clusters. We estimate a deformation of the CMB spectrum due to multiple Compton scattering of the photons off electrons of an optically-thin hot spherical plasma cloud. This new approach allows us to disentangle and determine the optical depth and the electron temperature of a galaxy cluster using the CMB observations.