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Discovery of a Radio Supernova Remnant and Non-thermal X-rays Coincident with the TeV Source HESS J1813-178

C. L. Brogan·B. M. Gaensler·J. D. Gelfand·J. S. Lazendic·T. J. Lazio·N. E. Kassim·N. M. McClure-Griffiths
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Abstract

We present the discovery of non-thermal radio and X-ray emission positionally coincident with the TeV $γ$-ray source HESS J1813--178. We demonstrate that the non-thermal radio emission is due to a young shell-type supernova remnant (SNR) G12.8--0.0, and constrain its distance to be greater than 4 kpc. The X-ray emission is primarily non-thermal and is consistent with either an SNR shell or unidentified pulsar/pulsar wind nebula origin; pulsed emission is not detected in archival ASCA data. A simple synchrotron+inverse Compton model for the broadband emission assuming that all of the emission arises from the SNR shell implies maximum energies of $(30-450)(B/10 microG)^{-0.5}$ TeV. Further observations are needed to confirm that the broadband emission has a common origin and better constrain the X-ray spectrum.

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C. L. Brogan, B. M. Gaensler, J. D. Gelfand, J. S. Lazendic, T. J. Lazio, N. E. Kassim, N. M. McClure-Griffiths. 2005-07-13. Discovery of a Radio Supernova Remnant and Non-thermal X-rays Coincident with the TeV Source HESS J1813-178. https://doi.org/10.1086/491471

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