The slow merger of massive stars: Merger types and post-merger evolution

Conference item

We study the slow merger of two massive stars inside a common envelope: The initial close binary system consists of a massive red supergiant and a main-sequence companion of a few solar, masses. The merger product is a massive supergiant with an interior structure (core mass and composition profile) which is significantly different from that of a single supergiant that has evolved in isolation: Using a parameterized approach for the stream-core interaction, we modelled the merger phase and have identified three qualitatively different merger types: quiet, moderate and explosive mergers, where the differences are caused by the different response of the He burning shell. In the last two scenarios, the post-merger He abundance in the envelope is found to be substantially increased, but significant s-processing is mainly expected in the case of an explosive merger scenario. The subsequent evolution of the merger product up to the supernova stage is also discussed.

Authors: Ivanova, N; Podsiadlowski, P

• Publication status: Published
• Journal: EXOTIC STARS AS CHALLENGES TO EVOLUTION, PROCEEDINGS
• Volume: 279
• Pages: 245-251
• Publication date: 2002-01-01
• Event title: 187 Colloquium on Exotic Stars as Challenges to Evolution
• ISBN: 1583811222
• Keywords: COMMON