# Probing the low-energy spectrum of non-thermal electrons in galaxy clusters with soft gamma ray observations

## TL;DR

This study explores the potential to detect low-energy non-thermal electrons in galaxy clusters via soft gamma ray emissions, but finds practical detection challenging due to short-lived conditions.

## Contribution

It assesses the feasibility of probing low-energy electron spectra in galaxy clusters through non-thermal bremsstrahlung with upcoming gamma-ray instruments.

## Key findings

- Detection is possible for very low electron energies but only under short-lived conditions.
- Practical constraints make constraining the low-energy spectrum in the near future difficult.
- The Coma cluster serves as a reference case for these assessments.

## Abstract

In this paper we study the possibility of probing the low-energy part of the spectrum of non-thermal electrons in galaxy clusters by detecting their non-thermal bremsstrahlung (NTB) emission in the soft gamma ray band, using instruments like e-ASTROGAM. Using the Coma cluster as a reference case, we find that, for very low values of the minimum energy of the electrons, in principle the NTB is detectable, but this situation is possible only for conditions that can be maintained only for a short time compared to the cluster lifetime. The possibility of constraining the low energy spectrum of non-thermal electrons through NTB is therefore hard to achieve in next years.