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arXiv · 2108.09536

X-ray Luminosity of Decades-Old Supernovae

Vandana Ramakrishnan·Vikram V. Dwarkadas
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Abstract

The transition from supernovae (SNe) to supernova remnants (SNRs) remains poorly understood, given the age gap between well-studied examples of the two. In order to bridge this gap, we analysed archival Chandra data for some of the oldest supernovae detected in X-rays, in order to extend their light curves out to late times. We fitted the spectra with thermal models. All the SNe with multiple X-ray data points were found to have similar X-ray luminosity, which was decreasing with time. The X-ray luminosity will likely continue to decrease while the SNe are evolving in a wind medium, but is anticipated to increase in the Sedov phase when the SNe are interacting with a constant density interstellar medium, bringing it in line with observed SNRs.

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Vandana Ramakrishnan, Vikram V. Dwarkadas. 2021-08-21. X-ray Luminosity of Decades-Old Supernovae. https://doi.org/10.3847/2515-5172%2Fac1e28

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