Discovery of the VHE gamma-ray source HESS J1832-093 in the vicinity of SNR G22.7-0.2

Abstract

The region around the supernova remnant (SNR) W41 contains several TeV sources and has prompted the H.E.S.S. Collaboration to perform deep observations of this field of view. This resulted in the discovery of the new very high energy (VHE) source HESS J1832-093, at the position $\mathrm{RA}=18^{\mathrm{h}}32^{\mathrm{m}}50^{\mathrm{s}}\pm 3_{\mathrm{stat}}^{\mathrm{s}}\pm 2_{\mathrm{syst}}^{\mathrm{s}},\mathrm{Dec}=-9^{\circ }22^{\prime }36^{\prime \prime }\pm 32_{\mathrm{stat}}^{\prime \prime }\pm 20_{\mathrm{syst}}^{\prime \prime }(J2000)$, spatially coincident with a part of the radio shell of the neighboring remnant G22.7-0.2. The photon spectrum is well described by a power-law of index $\Gamma =2.6\pm 0.3_{\mathrm{stat}}\pm 0.1_{\mathrm{syst}}$ and a normalization at 1 TeV of ${\Phi }_0=(4.8\pm 0.8_{\mathrm{stat}}\pm 1.0_{\mathrm{syst}})\times 10^{-13}{\mathrm{cm}}^{-2}{\mathrm{s}}^{-1}\mathrm{Te}{\mathrm{V}}^{-1}$. The location of the gamma-ray emission on the edge of the SNR rim first suggested a signature of escaping cosmic-rays illuminating a nearby molecular cloud. Then a dedicated XMM-Newton observation led to the discovery of a new X-ray point source spatially coincident with the TeV excess. Two other scenarios were hence proposed to identify the nature of HESS J1832-093. Gamma-rays from inverse Compton radiation in the framework of a pulsar wind nebula scenario or the possibility of gamma-ray production within a binary system are therefore also considered. Deeper multi-wavelength observations will help to shed new light on this intriguing VHE source.

6 pages, 4 figures

References in corpus (9)

• Observations of the Crab Nebula with H.E.S.S
• The Boston University-Five College Radio Astronomy Observatory Galactic Ring Survey
• The XMM-Newton EPIC Background and the production of Background Blank Sky Event Files
• Discovery of a point-like very-high-energy gamma-ray source in Monoceros
• HESS J0632+057 : A new gamma-ray binary?
• Periodic very high energy gamma-ray emission from LS I +61 303 observed with the MAGIC telescope
• Non-Thermal X-ray Properties of Rotation Powered Pulsars and Their Wind Nebulae
• A new analysis strategy for detection of faint gamma-ray sources with Imaging Atmospheric Cherenkov Telescopes
• Unified model for the gamma-ray emission of supernova remnants

Cited by in corpus (9)

• Overview of non-transient gamma-ray binaries and prospects for the Cherenkov Telescope Array
• A dynamical and radiation semi-analytical model of pulsar-star colliding winds along the orbit: Application to LS 5039
• Dense molecular gas at 12 mm towards Galactic TeV gamma-ray sources
• X-ray spectroscopy of the starburst feedback in 30 Doradus
• Prospects for a survey of the Galactic plane with the Cherenkov Telescope Array
• NuSTAR Hard X-ray Observation of the Gamma-ray Binary Candidate HESS J1832-093
• A multi-wavelength study of the gamma-ray binary candidate HESS J1832-093
• Possible TeV $\gamma$-ray binary origin of HESS J1828-099
• H.E.S.S.: The High Energy Stereoscopic System