Manuel Paz Arribas, Ullrich Schwanke, Iurii Sushch, Nukri Komin, Fabio Acero, Stefan Ohm, for the H. E. S. S. Collaboration
Supernova Remnants (SNRs) are believed to be acceleration sites of Galactic cosmic rays. Therefore, deep studies of these objects are instrumental for an understanding of the high energy processes in our Galaxy. \velajr, also known as Vela Junior, is one of the few (4) shell-type SNRs resolved at Very High Energies (VHE; $E > 100 \GeV$). It is one of the largest known VHE sources ($\sim 1.0^\circ$ radius) and its flux level is comparable to the flux level of the Crab Nebula in the same energy band. These characteristics allow for a detailed analysis, shedding further light on the high-energy processes taking place in the remnant. In this document we present further details on the spatial and spectral morphology derived with an extended data set. The analysis of the spectral morphology of the remnant is compatible with a constant power-law photon index of $2.11 \pm 0.05_{\rm stat} \pm 0.20_{\rm syst}$ from the whole SNR in the energy range from 0.5 TeV to 7 TeV. The analysis of the spatial morphology shows an enhanced emission towards the direction of the pulsar \psr, however as the pulsar is lying on the rim of the SNR, it is difficult to disentangle both contributions. Therefore, assuming a point source, the upper limit on the flux of the pulsar wind nebula (PWN) between 1 TeV and 10 TeV, is estimated to be $\sim 2%$ of the Crab Nebula flux in the same energy range.
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http://arxiv.org/abs/1203.2532
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