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Detection of thermal X-ray emission in the halo of the plerionic supernova remnant G21.5-0.9

F. Bocchino
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Abstract

The detection of a soft thermal X-ray component in the spectrum of a bright knot in the halo of the plerion G21.5-0.9 is reported. Using a collisional ionization equilibrium model for an hot optically thin plasma, a temperature $kT=0.12-0.24$ kev, a mass of 0.3--1.0 M$_\odot$ and a density of 1.6-6 cm$^{-3}$ is derived. The spectral analysis suggests a possible overabundance of Silicon with respect to the solar value in the knot; if this will be confirmed this object may be a clump of shocked ejecta.

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F. Bocchino. 2005-01-24. Detection of thermal X-ray emission in the halo of the plerionic supernova remnant G21.5-0.9. https://doi.org/10.1016/j.asr.2005.01.045

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