A statistical view on stable and unstable Roche lobe overflow of a tertiary star onto the inner binary in triple systems

Understand

In compact stellar triple systems, an evolved tertiary star can overflow its Roche lobe around the inner binary.

• Subsequently, the tertiary star can transfer mass to the inner binary in a stable manner, or Roche lobe overflow (RLOF) can be unstable and lead to common-envelope (CE) evolution.
• In the latter case, the inner binary enters the extended envelope of the tertiary star and spirals in towards the donor's core, potentially leading to mergers or ejections.
• Although studied in detail for individual systems, a comprehensive statistical view on the various outcomes of triple RLOF is lacking.