Potential Gamma-ray Emissions from Low-Mass X-ray Binary Jets

TL;DR

This study models gamma-ray emissions from low-mass X-ray binary jets using a leptonic approach, predicting detectable TeV and GeV signals that can be tested by Fermi and CTA telescopes.

Contribution

It introduces a comprehensive leptonic radiation model for jet emissions in low-mass X-ray binaries, including electron evolution and radiative processes, and applies it to GX 339-4.

Findings

Spectral energy distributions extend up to TeV bands.

Model reproduces observations of GX 339-4.

Predicts detectable gamma-ray signals for future telescopes.

Abstract

By proposing a pure leptonic radiation model, we study the potential gamma-ray emissions from jets of the low-mass X-ray binaries. In this model, the relativistic electrons that are accelerated in the jets are responsible for radiative outputs. Nevertheless, dynamics of jets are dominated by the magnetic and proton-matter kinetic energies. The model involves all kinds of related radiative processes and considers the evolution of relativistic electrons along the jet by numerically solving the kinetic equation. Numerical results show that the spectral energy distributions can extend up to TeV bands, in which synchrotron radiation and synchrotron self-Compton scattering are dominant components. As an example, we apply the model to the low-mass X-ray binary GX 339-4. The results can not only reproduce the currently available observations from GX 339-4, but also predict detectable radiation at GeV and TeV bands by Fermi and CTA telescopes. The future observations with Fermi and CTA can be used to test our model, which could be employed to distinguish the origin of X-ray emissions.