Kinematics of X-ray Emitting Components in Cassiopeia A

T. DeLaney; L. Rudnick; R. Fesen; T. W. Jones; R. Petre; J. A. Morse

doi:10.1086/422906

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arXiv · astro-ph/0406045

Kinematics of X-ray Emitting Components in Cassiopeia A

T. DeLaney·L. Rudnick·R. Fesen·T. W. Jones·R. Petre·J. A. Morse

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Abstract

We present high-resolution X-ray proper motion measurements of Cassiopeia A using Chandra observations from 2000 and 2002. We separate the emission into four spectrally distinct classes: Si-dominated, Fe-dominated, low-energy-enhanced, and continuum-dominated. These classes also represent distinct spatial and kinematic components. The Si- and Fe-dominated classes are ejecta and have a mean expansion rate of 0.2%/yr. This is the same as for the forward shock filaments but less than the 0.3%/yr characteristic of optical ejecta. The low-energy-enhanced spectral class possibly illuminates a clumpy circumstellar component and has a mean expansion rate of 0.05%/yr. The continuum-dominated emission likely represents the forward shock and consists of diffuse circumstellar material which is seen as a circular ring around the periphery of the remnant as well as projected across the center.

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T. DeLaney, L. Rudnick, R. Fesen, T. W. Jones, R. Petre, J. A. Morse. 2004-06-01. Kinematics of X-ray Emitting Components in Cassiopeia A. https://doi.org/10.1086/422906

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