Super Winds and Radio Emission in X-ray Binary Systems

TL;DR

This paper explores how supercritical colliding wind binaries in X-ray systems accelerate particles and produce broadband nonthermal radiation, with detailed modeling of the accretion disk wind to understand these emissions.

Contribution

It provides a detailed description of the accretion disk wind in supercritical colliding wind binaries, enhancing understanding of particle acceleration and nonthermal radiation processes in these systems.

Findings

Estimated radio luminosity of about 10^{34} erg/s.

Identified the wind's role in powering nonthermal emissions.

Analyzed wind properties affecting radiation absorption and reprocessing.

Abstract

We have recently proposed that supercritical colliding wind binaries (SCWBs) are suitable scenarios for particle acceleration and nonthermal radiation. In these X-ray binary systems (XRBs), the wind from the companion star collides with the wind ejected from the super-Eddington accretion disk of the stellar black hole. Strong shocks are generated in this collision, leading to the acceleration of particles and subsequent broadband emission through different nonthermal radiative processes. In particular, we estimate luminosities of the order of $L\approx 10^{34}\,{\rm erg\,s^{-1}}$ in the radio band. One of the major components in these processes is the power provided by the super wind expelled from the disk. Furthermore, some properties of the wind photosphere, such as its geometry or its temperature distribution, also contribute to the absorption and reprocessing of the nonthermal radiation. In this work, we perform a more detailed description of the powerful wind launched from the accretion disk, in order to obtain a better understanding of the above-mentioned processes.