VHE Observations of Galactic binary systems with VERITAS

TL;DR

This paper reports on VHE gamma-ray observations of Galactic binary systems, including a new discovery program and an eleven-year study of HESS J0632+057, enhancing understanding of particle acceleration and emission variability.

Contribution

It presents the first results from VERITAS binary discovery program at VHE energies and summarizes extensive observations of HESS J0632+057 over eleven years.

Findings

Detection of VHE gamma-ray emission from HESS J0632+057

Over 220 hours of VERITAS observations conducted

Correlated X-ray and gamma-ray variability analyzed

Abstract

Gamma-ray binaries are variable sources of GeV-to-TeV photons with the peak in their spectral energy distributions above 100 MeV. There are only five Galactic gamma-ray binaries known and the processes which govern particle acceleration, non-thermal emission and the variability patterns are not well understood. We present here for the first time results of the VERITAS binary discovery program at VHE energies and a summary of eleven years of observations of the gamma-ray binary HESS J0632+057. VERITAS has acquired more than 220 hours of observations on HESS J0632+057. The results are discussed in the context of contemporaneous observations with Swift XRT at X-ray energies.