Tracing the role of AGB stars in the Galactic Fluorine budget

TL;DR

This paper reviews the potential role of AGB stars in producing galactic fluorine, emphasizing the need for high-resolution ALMA observations of AlF to clarify their contribution to the fluorine budget.

Contribution

It proposes using ALMA observations of AlF as a new method to quantify AGB stars' contribution to galactic fluorine production.

Findings

Review of stellar yield models for fluorine synthesis.

Highlighting previous detections of F-bearing molecules in AGB stars.

Proposal for ALMA observations to trace fluorine in AGB outflows.

Abstract

The cosmic origin of fluorine is still under debate. Asymptotic giant branch (AGB) stars are among the few suggested candidates to efficiently synthesis F in our Galaxy, however their relative contribution is not clear. In this paper, we briefly review the theoretical studies from stellar yield models of the F synthesis and chemical equilibrium models of the F-containing molecules in the outflow around AGB stars. Previous detections of the F-bearing species towards AGB and post-AGB stars are also highlighted. We suggest that high-resolution ALMA observations of the AlF, one of the two main carriers of F in the outflow of AGB stars, can provide a reliable tracer of the F-budget in AGB stars. This will be helpful to quantify the role of AGB stars in the Galactic F budget.