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A New ASCA and ROSAT Study of the Supernova Remnant: G272.2-3.2

I. M. Harrus·P. O. Slane·R. Smith·J. P. Hughes
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Abstract

G272.2-3.2 is a supernova remnant (SNR) characterized by an apparent centrally brightened X-ray morphology and thermally dominated X-ray emission. Because of this combination of Sedov-type (thermal emission) and non-Sedov type (non-shell like morphology) features, the remnant is classified as a ``thermal composite'' SNR. This class of remnant is still poorly understood due in part to the difficulties in modeling accurately all the physical conditions which shape the emission morphology. In this paper we present a combined analysis of data from the ASCA and ROSAT satellites coupled with previous results at other wavelengths. We find that the X-ray emission from G272.2-3.2 is best described by a non-equilibrium ionization (NEI) model with a temperature around 0.70 keV, an ionization timescale of 3200 cm^-3 yr and a relatively high column density (NH about 10^22 atoms/cm^2). We look into the possible explanations for the apparent morphology of G272.2-3.2 using several models (among which both cloud evaporation and thermal conduction models). For each of the models considered we examine all the implications on the evolution of G272.2-3.2.

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I. M. Harrus, P. O. Slane, R. Smith, J. P. Hughes. 2001-01-16. A New ASCA and ROSAT Study of the Supernova Remnant: G272.2-3.2. https://doi.org/10.1086/320577

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