Rare events of a peculiar thermonuclear supernova that precedes a core collapse supernova

TL;DR

This paper models rare binary star evolution scenarios where a white dwarf explodes as a peculiar Type Ia supernova shortly before its companion's core-collapse supernova, predicting observable sequential supernovae events.

Contribution

It introduces a new evolutionary pathway for binary systems leading to sequential supernovae, combining thermonuclear and core-collapse explosions in a single evolutionary sequence.

Findings

Simulated binary evolution with MESA-binary shows possible timing of supernovae.

Predicted occurrence of a peculiar SN Ia followed by a CCSN within months to years.

Rare event scenario with specific orbital and evolutionary conditions.

Abstract

We study stellar binary evolution that leads to the formation of a white dwarf (WD) that explodes in a thermonuclear supernova at the termination of a common envelope evolution (CEE) shortly before the core of its companion explodes as a core-collapse supernova (CCSN). The CCSN explosion of the core, which is the remnant of a red supergiant (RSG) star, might take place few months to several years after the explosion of the WD as a thermonuclear supernova, i.e., a type Ia peculiar supernova (peculiar SN Ia). Using the evolutionary code MESA-binary we simulate evolution of binary systems with stars of initial masses of 6-7.5Mo. The more massive star, the primary, transfers mass to the secondary star and leaves a CO WD remnant. The secondary becomes massive enough to end in a CCSN. As the secondary evolves to the RSG phase it engulfs the WD and the system experience a CEE that ends with a WD-core binary system at an orbital separation of a_f ~ 1-5Ro. Our simulations show that the core explodes as a CCSN at t_{CEE-CCSN} ~ 3000 - 10^5 yr after the CEE. We assume that if the WD accretes helium-rich gas from the core it might explode as a SN Ia in the frame of the double detonation scenario for SNe Ia and peculiar SNe Ia. We predict the very rare occurrence of a peculiar SN Ia followed within months to years by a CCSN.