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The nature of the X-ray halo of the plerion G21.5-0.9 unveiled by XMM-Newton and Chandra

F. Bocchino·E. van der Swaluw·R. Chevalier·R. Bandiera
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Abstract

The nature of the radio-quiet X-ray halo around the plerionic SNR G21.5-0.9 is under debate. On the basis of spatial and spectral analysis of a large Chandra and XMM-Newton dataset of this source, we have developed a self-consistent scenario which explains all the observational features. We found that the halo is composed by diffuse extended emission due to dust scattering of X-rays from the plerion, by a bright limb which traces particle acceleration in the fast forward shock of the remnant, and by a bright spot (the ``North Spur'') which may be a knot of ejecta in adiabatic expansion. By applying a model of interaction between the PWN, the SNR and supernova environment, we argue that G21.5-0.9 progenitor may be of Type IIP or Ib/Ic, and that the remnant may be young (200-1000 yr).

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F. Bocchino, E. van der Swaluw, R. Chevalier, R. Bandiera. 2005-07-21. The nature of the X-ray halo of the plerion G21.5-0.9 unveiled by XMM-Newton and Chandra. https://doi.org/10.1051/0004-6361%3A20052870

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