Non-thermal radiation from Cygnus X-1 corona

TL;DR

This paper presents a comprehensive model of Cygnus X-1's corona, incorporating relativistic particles and secondary emissions to explain its non-thermal radiation across multiple energy bands.

Contribution

It introduces a detailed corona model with both leptonic and hadronic components, including secondary particle interactions and photon absorption effects.

Findings

Model reproduces observed gamma-ray data from Cygnus X-1.

Highlights the role of secondary particles in high-energy emission.

Provides insights into particle acceleration in black hole coronae.

Abstract

Cygnus X-1 was the first X-ray source widely accepted to be a black hole candidate and remains among the most studied astronomical objects in its class. The detection of non-thermal radio, hard X-rays and gamma rays reveals the fact that this kind of objects are capable of accelerating particles up to very high energies. In order to explain the electromagnetic emission from Cygnus X-1 in the low-hard state we present a model of a black hole corona with both relativistic lepton and hadron content. We characterize the corona as a two-temperature hot plasma plus a mixed non-thermal population in which energetic particles interact with magnetic, photon and matter fields. Our calculations include the radiation emitted by secondary particles (pions, muons and electron/positron pairs). Finally, we take into account the effects of photon absorption. We compare the results obtained from our model with data of Cygnus X-1 obtained by the COMPTEL instrument.