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تسجيل مستخدم جديدHigh spatial resolution X-ray spectroscopy of SNR Cassiopeia A with {sl Chandra}
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We present high spatial resolution X-ray spectroscopy of supernova remnant Cassiopeia A with the {sl Chandra} observations. The X-ray emitting region of this remnant was divided into 38 $times$ 34 pixels with a scale of 10$arcsec$ $times$ 10$arcsec$ each. Spectra of 960 pixels were created and fitted with an absorbed two component non-equilibrium ionization model. With the spectral analysis results we obtained maps of absorbing column density, temperatures, ionization ages, and the abundances for Ne, Mg, Si, S, Ca and Fe. The Si, S and possibly Ca abundance maps show obviously jet structures, while Fe doesnt follow the jet but seems to be distributed perpendicular to it. In the range of about two orders of magnitude, the abundances of Si, S and Ca show tight correlations between each other, suggesting them to be ejecta from explosive O-burning and incomplete Si-burning. Meanwhile, Ne abundance is well correlated with that of Mg, indicating them to be the ashes of explosive C/Ne burning. The Fe abundance is positively correlated with that of Si when Si abundance is lower than 3 solar abundances, but a negative correlation appears when the Si abundance is higher. We suggest that such a two phase correlation is the results of different ways in which Fe is synthesized.
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