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arXiv · 2104.03694

An Analytical Density Profile of Dense Circumstellar Medium in Type II Supernovae

Daichi Tsuna·Yuki Takei·Naoto Kuriyama·Toshikazu Shigeyama
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Abstract

Observations of Type II supernovae imply that a large fraction of its progenitors experience enhanced mass loss years to decades before core collapse, creating a dense circumstellar medium (CSM). Assuming that the CSM is produced by a single mass eruption event, we analytically model the density profile of the resulting CSM. We find that a double power-law profile, where the inner (outer) power-law index has a characteristic value of -1.5 (-10 to -12), gives a good fit to the CSM profile obtained using radiation hydrodynamical simulations. With our profile the CSM is well described by just two parameters, the transition radius $r_*$ and density at $r=r_*$ (alternatively $r_*$ and the total CSM mass). We encourage future studies to include this profile, if possible, when modelling emission from interaction-powered transients.

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Daichi Tsuna, Yuki Takei, Naoto Kuriyama, Toshikazu Shigeyama. 2021-05-31. An Analytical Density Profile of Dense Circumstellar Medium in Type II Supernovae. https://doi.org/10.1093/pasj%2Fpsab063

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