# Origin of X-ray and gamma-ray emission from the Galactic central region

## TL;DR

This study investigates whether the non-thermal X-ray and gamma-ray emissions from the Galactic Center originate from a common source, analyzing hadronic and leptonic models to explain observed phenomena.

## Contribution

It provides a detailed analysis of the origin of high-energy emissions in the Galactic Center, evaluating hadronic and leptonic scenarios against observational data.

## Key findings

- Pure hadronic models underestimate X-ray flux.
- Protons contribute minimally to hard X-ray emission.
- Leptonic models can reproduce both X-ray and gamma-ray emissions.

## Abstract

We study a possible connection between different non-thermal emissions from the inner few parsecs of the Galaxy. We analyze the origin of the gamma-ray source 2FGL J1745.6-2858 (or 3FGL J1745.6-2859c) in the Galactic Center and the diffuse hard X-ray component recently found by NuSTAR, as well as the radio emission and processes of hydrogen ionization from this area. We assume that a source in the GC injected energetic particles with power-law spectrum into the surrounding medium in the past or continues to inject until now. The energetic particles may be protons, electrons or a combination of both. These particles diffuse to the surrounding medium and interact with gas, magnetic field and background photons to produce non-thermal emissions. We study the spectral and spatial features of the hard X-ray emission and gamma-ray emission by the particles from the central source. Our goal is to examine whether the hard X-ray and gamma-ray emissions have a common origin. Our estimations show that in the case of pure hadronic models the expected flux of hard X-ray emission is too low. Despite protons can produce a non-zero contribution in gamma-ray emission, it is unlikely that they and their secondary electrons can make a significant contribution in hard X-ray flux. In the case of pure leptonic models it is possible to reproduce both X-ray and gamma-ray emissions for both transient and continuous supply models. However, in the case of continuous supply model the ionization rate of molecular hydrogen may significantly exceed the observed value.