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arXiv · 1807.06369

X-ray Swift observations of SN 2018cow

L. E. Rivera Sandoval·T. J. Maccarone·A. Corsi·P. J. Brown·D. Pooley·J. C. Wheeler
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Abstract

Supernova (SN) 2018cow (or AT2018cow) is an optical transient detected in the galaxy CGCG 137-068. It has been classified as a SN due to various characteristics in its optical spectra. The transient is also a bright X-ray source. We present results of the analysis of ~62ks of X-ray observations taken with the Neil Gehrels Swift Observatory over 27 days. We found a variable behavior in the 0.3-10 keV X-ray light curve of SN 2018cow, with variability timescales of days. The observed X-ray variability could be due to the interaction between the SN ejecta and a non-uniform circumstellar medium, perhaps related to previous mass ejections from a luminous-blue-variable-like progenitor.

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L. E. Rivera Sandoval, T. J. Maccarone, A. Corsi, P. J. Brown, D. Pooley, J. C. Wheeler. 2018-07-17. X-ray Swift observations of SN 2018cow. https://doi.org/10.1093/mnrasl/sly145

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