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arXiv · astro-ph/9910113

Impacts of the Detection of Cassiopeia A Point Source

Abstract

Very recently the Chandra First Light Observation discovered a point-like source in Cassiopeia A (Cas A) supernova remnant. This detection was subsequently confirmed by the analyses of the archival data from both ROSAT and Einstein observations. Here we compare the results from these observations with the scenarios involving both black holes (BH) and neutron stars (NS). If this point source is a BH we offer as a promising model a disk-corona type model with low accretion rate where a soft photon source at ~ 0.1 keV is Comptonized by higher energy electrons in the corona. If it is a NS the dominant radiation observed by Chandra most likely originates from smaller, hotter regions of the stellar surface, but we argue that it is still worthwhile to compare the cooler component from the rest of the surface with cooling theories. We emphasize that the detection of this point source itself should potentially provide enormous impacts on the theories of supernova explosion, progenitor scenario, compact remnant formation, accretion to compact objects, and neutron star thermal evolution.

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H. Umeda, K. Nomoto, S. Tsuruta, S. Mineshige. 2000-03-25. Impacts of the Detection of Cassiopeia A Point Source. https://doi.org/10.1086/312680

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