Simulations of stripped core-collapse supernovae in close binaries

TL;DR

This study uses smoothed-particle hydrodynamical simulations to analyze how a supernova explosion in a close binary system affects the companion star and the supernova remnant, revealing asymmetries and material exchange.

Contribution

It provides detailed simulation results on the impact of a core-collapse supernova on a binary companion and the resulting asymmetries in the supernova remnant structure.

Findings

Companion star loses mass and gains velocity kick.

Supernova remnant develops a conical cavity due to the companion.

Remnant shows asymmetric metal and hydrogen distribution.

Abstract

We perform smoothed-particle hydrodynamical simulations of the explosion of a helium star in a close binary system, and study the effects of the explosion on the companion star as well as the effect of the presence of the companion on the supernova remnant. By simulating the mechanism of the supernova from just after core bounce until the remnant shell passes the stellar companion, we are able to separate the various effects leading to the final system parameters. In the final system, we measure the mass stripping and ablation from, and the velocity kick imparted to, the companion star, as well as the structure of the supernova shell. The presence of the companion star produces a conical cavity in the expanding supernova remnant, and loss of material from the companion causes the supernova remnant to be more metal-rich on one side and more hydrogen-rich (from the companion material) around the cavity. Following the removal of mass from the companion, we study its subsequent evolution and compare it with a single star not subjected to a supernova impact.