Light elements in massive single and binary stars

TL;DR

This paper discusses how light elements, especially boron, serve as diagnostic tools to understand the internal processes and evolutionary history of massive single and binary stars.

Contribution

It reveals that boron surface abundance provides unique insights into internal mixing and past mass transfer events in massive stars, offering new constraints on stellar evolution.

Findings

Boron surface abundance constrains internal mixing.

Boron indicates previous mass transfer in binaries.

Boron helps explain nitrogen-rich slow rotators.

Abstract

We highlight the role of the light elements (Li, Be, B) in the evolution of massive single and binary stars, which is largely restricted to a diagnostic value, and foremost so for the element boron. However, we show that the boron surface abundance in massive early type stars contains key information about their foregoing evolution which is not obtainable otherwise. In particular, it allows to constrain internal mixing processes and potential previous mass transfer event for binary stars (even if the companion has disappeared). It may also help solving the mystery of the slowly rotating nitrogen-rich massive main sequence stars.