Binary Interaction Can Yield a Diversity of Circumstellar Media around Type II Supernova Progenitors

Tomoki Matsuoka^1*, Ryo Sawada²

¹Institute of Astronomy and Astrophysics, Academia Sinica, Taipei, Taiwan
²Department of Earth Science and Astronomy, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan

* Presenter:Tomoki Matsuoka, email:tmatsuoka@asiaa.sinica.edu.tw

Recent observations of supernovae have indicated that a fraction of massive stars possess dense circumstellar medium at the moment of their core collapses. They suggest the presence of additional activities of the supernova progenitor driving the enhancement of the mass-loss rate, and some physical processes attributing to single star's activities have been considered. Here, we carry out binary evolutionary simulations of massive stars by MESA and investigate effects on the subsequent circumstellar medium formation through hydrodynamical simulations by PLUTO. We show that the mass-transfer rate in a binary can increase at the beginning of the Roche lobe overflow, and this enhancement would be associated with the structure of the circumstellar medium before the explosion. We also illustrate that depending on the orbital period of the binary, the density structure of the circumstellar medium can have a diverse distribution including shell-like and cliff-like structures. These characteristic structures appear within the lengthscale of 10¹⁷ cm and could be traced by long-term observations of supernovae, if the slow velocity of the circumstellar medium is assumed (~10km/s). Our results highlight the importance of binary interaction in the aspect of reproducing the diversity of the circumstellar medium configuration.

Keywords: massive stars, binary evolution, supernova, circumstellar medium