HESS J1832-085: Evidence of a new gamma-ray binary candidate

The Galactic plane survey conducted by the High Energy Stereoscopic System (H.E.S.S.) has revealed numerous teraelectronvolt (TeV) sources, many of which remain unidentified. HESS J1832-085 is a point-like TeV source lacking a confirmed multiwavelength (MWL) counterpart. In this paper, we present evidence supporting a gamma-ray binary interpretation of HESS J1832-085 . We aim to investigate the nature of HESS J1832-085 using the available X-ray and Fermi Large Area Telescope (LAT) data, complemented by a near-infrared (NIR) identification of a possible stellar companion and broadband radiative modeling, to assess its classification as a potential gamma-ray binary. Archival X-ray observations were examined to search for a counterpart and to characterize its spectrum and potential variability. We further analyzed ∼17.3 yrs of Fermi LAT data between 1 and 300 GeV to establish a possible gigaelectronvolt (GeV) counterpart of HESS J1832-085. We also examined archival NIR images from the UKIRT Infrared Deep Sky Survey (UKIDSS) and the Two Micron All Sky Survey (2MASS), together with 2MASS catalog photometry. The broadband emission was interpreted using models commonly applied to gamma-ray binaries. A potential X-ray counterpart was identified in archival X-ray data, exhibiting a hard, absorbed spectrum and moderate variability. We also identified a tentative GeV gamma-ray excess that is spatially consistent with HESS J1832-085 and the proposed X-ray counterpart. We further identified a candidate stellar counterpart in both the UKIDSS and 2MASS images, located in close spatial proximity to the X-ray counterpart. The adopted illustrative binary radiative model broadly reproduces the X-ray and TeV emission, but fails to explain the emission from the tentative GeV excess. Our results support HESS J1832-085 as a promising gamma-ray binary candidate , motivating dedicated MWL follow-up observations to confirm the source nature.