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The hard X-ray and Ti-44 emission of Cas A

Jacco Vink·Jelle S. Kaastra·Johan A. M. Bleeker·Hans Bloemen
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Abstract

We present an analysis of the BeppoSAX high X-ray energy spectrum of the supernova remnant Cassiopeia A with an observation time of 83 ks. We measure a flux upper limit of 4.1E-5 ph/cm^2/s (99.7% confidence) of the nuclear decay lines of Ti-44 at 68 keV and 78 keV that is lower and inconsistent with the flux of an accompanying line at 1157 keV measured by CGRO's Comptel. However, if the underlying X-ray continuum is lower, because the spectrum is steepening, the actual Ti-44 flux may be higher and consistent with the Comptel result, although the measured flux of (2.9 +/- 1.0)E-5 ph/cm^2/s under this assumption is still lower than the flux measured by Comptel.

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Jacco Vink, Jelle S. Kaastra, Johan A. M. Bleeker, Hans Bloemen. 1999-06-29. The hard X-ray and Ti-44 emission of Cas A. https://doi.org/10.1016/s0273-1177(99)00823-6

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