2007ApJ...665.1297H

We present a Chandra X-ray observation of G12.82-0.02, a shell-like radio supernova remnant coincident with the TeV gamma-ray source HESS J1813-178. We resolve the X-ray emission from the colocated Advanced Satellite for Cosmology and Astrophysics (ASCA) source into a point source surrounded by structured diffuse emission that fills the interior of the radio shell. The morphology of the diffuse emission strongly resembles that of a pulsar wind nebula. The spectrum of the compact source is well characterized by a power law with index Γ~1.3, typical of young and energetic rotation-powered pulsars. For a distance of 4.5 kpc, consistent with the X-ray absorption and an association with the nearby star formation region W33, the 2-10 keV X-ray luminosities of the putative pulsar and nebula are L_PSR=3.2x10³³ ergs/s and L_PWN=1.4x10³⁴ ergs/s, respectively. Both the flux ratio of L_PWN/L_PSR=4.3 and the total luminosity of this system predict a pulsar spin-down power of E{dot}>10³⁷ ergs/s^, placing it among the 10 most energetic young pulsars in the Galaxy. A deep search for radio pulsations using the Parkes telescope sets an upper limit of ~0.07 mJy at 1.4 GHz for periods ≳50 ms. We discuss the energetics of this source and consider briefly the proximity of bright H II regions to this and several other High Energy Stereoscopic System (H.E.S.S.) sources, which may produce their TeV emission via inverse Compton scattering.