Anisotropic scattering from the circumstellar disc in PSR B1259-63

TL;DR

This paper models the gamma-ray binary system PSR B1259-63, focusing on anisotropic inverse Compton scattering involving the circumstellar disc, to better understand its high-energy emission mechanisms.

Contribution

It introduces a comprehensive anisotropic inverse Compton scattering model that incorporates IR excess from the circumstellar disc, advancing the understanding of gamma-ray production in such systems.

Findings

Model successfully explains observed gamma-ray emissions.

Highlights the importance of disc IR excess in scattering processes.

Provides insights into anisotropic effects on high-energy emission.

Abstract

The gamma-ray binary system PSR B1259-63 has recently passed through periastron and has been of particular interest as it was observed by Fermi near the December 2010 periastron passage. The system has been detected at very high energies with H.E.S.S. The most probable production mechanism is inverse Compton scattering between target photons from the optical companion and disc, and relativistic electrons in the pulsar wind. We present results of a full anisotropic inverse Compton scattering model of the system, taking into account the IR excess from the extended circumstellar disc around the optical companion.