We investigate the nature of the unidentified very-high-energy (VHE) gamma-ray object, HESS J1832-093, in a multi-wavelength context. Based on X-ray variability and spectral index (ΓX∼1.5), and its broad-band spectrum (which was remarkably similar to HESS J0632+057, a confirmed gamma-ray binary), HESS J1832-093 has been considered to be a strong gamma-ray binary candidate in previous works. In this work, we provide further evidence for this scenario. We obtained a spectrum of its IR counterpart using Gemini/Flamingo, finding absorption lines that are usually seen in massive stars, in particular O stars. We also obtained a rather steep ATCA spectrum (α=−1.18−0.88+1.04) which prefers a gamma-ray binary over an AGN scenario. Based on spatial-spectral analysis and variability search, we found that 4FGL J1832.9-0913 is possible to be associated with SNR G22.7-0.2 rather than with HESS J1832-093 only.
@article{arxiv.2001.07138,
title = {A multi-wavelength study of the gamma-ray binary candidate HESS J1832-093},
author = {Pak-Hin Thomas Tam and K. K. Lee and Yudong Cui and A. K. H. Kong and K. L. Li and Vlad Tudor and Xinbo He and C. P. Hu and Partha S. Pal},
journal= {arXiv preprint arXiv:2001.07138},
year = {2020}
}