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Search for >= 400 GeV gamma-rays from the SNR Cas A

P. Goret·C. Gouiffes·E. Nuss·D. C. Ellison
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Abstract

The recent detection of a hard X-ray component in the supernova remnant Cassiopeia A is interpreted as synchrotron emission from electrons accelerated to energies up to 40 TeV (Allen et al., 1997). It is therefore tempting to consider TeV gamma-ray emission from this object through : i) bremsstrahlung and inverse Compton radiation from electrons and/or ii) pi0 production from an associated high energy cosmic ray component hitting surrounding material. Cas A was observed by the CAT imaging Cherenkov telescope during the observing season Aug-Nov 1998. An upper limit to the integral flux above 400 GeV of 0.74x10^-11 gamma.cm^-2.s^-1 is derived. This result is used to constrain shock-acceleration models for production of VHE gamma-rays in SNRs.

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P. Goret, C. Gouiffes, E. Nuss, D. C. Ellison. 1999-06-02. Search for >= 400 GeV gamma-rays from the SNR Cas A. https://arxiv.org/abs/astro-ph/9906040

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