How important are metal-poor AGB stars as cosmic dust producers?

TL;DR

This paper investigates how metal-poor AGB stars contribute to cosmic dust production, finding that their efficiency is limited by metallicity effects, which impacts their overall role in cosmic dust enrichment.

Contribution

The study confirms that dust and wind formation in metal-poor carbon stars is physically inefficient, highlighting limitations in their contribution to cosmic dust buildup.

Findings

Dust formation is less efficient in metal-poor AGB stars.

Metallicity limits the dust supply from AGB stars.

AGB stars' contribution to cosmic dust is likely smaller than previously thought.

Abstract

The efficiency of dust formation in oxygen-rich AGB stars should (in theory) be metallicity dependent since they are not producing their own raw material for dust production. Metal-poor carbon stars may not be very efficient dust producers either, because of more radiative heating of the grains forming in their atmospheres. We have just confirmed that inefficient dust and wind formation in simulations of metal-poor carbon stars is a real physical effect, albeit within the limitations of our simulations. Taken at face value, this implies that the amount of dust supplied by low-metallicity AGB stars to the build up of the cosmic dust component is clearly limited. Consequently, one may also ask how large a contribution AGB stars can make in general, when compared to recent observations of cosmic dust, which are suggesting major contributions from other sources?