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A synoptic spectral study of Cassiopeia-A based on XMM-Newton and BeppoSax observations

Johan Bleeker·Jacco Vink·Kurt van der Heyden·Dick Willingale·Jelle Kaastra·Martin Laming
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Abstract

In this paper we present recent image and spectral data of Cas-A obtained with XMM-Newton and BeppoSAX. Analysis of the hard X-ray continuum does not support an interpretation of the hard X-radiation as synchrotron emission produced in the primary shock, non-thermal Bremsstrahlung is a plausible alternative. Moreover, a recent 500 kilosecond deep observation of the hard X-ray continuum by BeppoSAX has revealed the positive detection of the 44Sc nuclear decay lines at 67.9 and 78.4 keV. Appropriate modelling of the hard X-ray continuum leads to an estimate of the initial 44Ti mass of (0.8-2.5)E-4 solar masses. We also present ionisation age, temperature, abundances maps. The observed elemental abundance ratio patterns can be reconciled best with a type Ib SNe, arising from a 60 solar mass progenitor (ZAMS) with high-mass-loss. The accurate modeling of the image-resolved emission line spectra has enabled us to derive reliable Doppler velocities for the bright Si-K, S-K, and Fe-K line complexes.

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Johan Bleeker, Jacco Vink, Kurt van der Heyden, Dick Willingale, Jelle Kaastra, Martin Laming. 2002-02-11. A synoptic spectral study of Cassiopeia-A based on XMM-Newton and BeppoSax observations. https://arxiv.org/abs/astro-ph/0202207

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