VERITAS and H.E.S.S. observations of the gamma-ray binary HESS J0632+057

TL;DR

This paper reports on multi-year observations of the gamma-ray binary HESS J0632+057 using VERITAS and H.E.S.S., revealing phase-dependent TeV gamma-ray emission and expanding the understanding of its variability and multiwavelength behavior.

Contribution

It provides the first TeV observations at previously unexplored orbital phases, enhancing knowledge of the system's gamma-ray variability and emission characteristics.

Findings

Detection of TeV gamma-rays at orbital phase 0.3 with high significance.

First TeV observations at new orbital phases.

Correlation of gamma-ray data with multiwavelength observations.

Abstract

HESS J0632+057 has been recently identified as a new gamma-ray binary system. The source, located in the Monoceros region and associated with the massive Be star MWC 148, shows variability from radio to very high energy (VHE) gamma-rays, displaying a maximum of its non-thermal emission about 100 days after periastron passage (at orbital phases close to 0.3). We present here the results obtained with the VERITAS and H.E.S.S Cherenkov telescopes spanning a wide time interval from 2004 to 2012. The source is detected at TeV gamma-rays at a high significance level at orbital phase 0.3. We also report for the first time TeV observations belonging to orbital phases never explored so far. The VHE gamma-ray results are discussed in a multiwavelength context, focusing on contemporaneous observations obtained with the Swift-XRT.