The strange case of HESS J0632+057 and the \gamma-ray High Mass X-ray Binaries

TL;DR

This paper investigates the gamma-ray emission of the high mass X-ray binary HESS J0632+057 using over 3.5 years of Fermi-LAT data, comparing its properties with other gamma-ray binaries.

Contribution

It provides the first deep search for gamma-ray emission from HESS J0632+057 at GeV energies and compares its characteristics with similar systems.

Findings

No significant gamma-ray detection at GeV energies for HESS J0632+057.

Constraints on gamma-ray flux from HESS J0632+057.

Comparison highlights differences and similarities with other gamma-ray binaries.

Abstract

In the last decade Cherenkov telescopes on the ground and space-based \gamma-ray instruments have identified a new class of high mass X-ray binaries (HMXB), whose emission is dominated by \gamma rays. To date only five of these systems are known. All of them are detected by Cherenkov telescopes in the TeV energy range, while at GeV energies there is still one (HESS J0632+057) that has no reported detection with the Fermi-LAT. A deep search for \gamma-ray emission of HESS J0632+057 has been performed using more than 3.5 years of Fermi-LAT data. We discuss the results of this search and compare it to other \gamma-ray binary systems.