The Global Gas and Dust budge of the Large Magellanic Cloud --- Importance of Asymptotic Giant Branch stars

TL;DR

This study quantifies the contribution of AGB stars to the gas and dust content in the Large Magellanic Cloud, using infrared observations and a new classification scheme to measure their mass-loss rates.

Contribution

It introduces an infrared colour classification scheme for AGB stars and estimates their total gas and dust contribution in the LMC.

Findings

AGB stars significantly contribute to the gas and dust in the LMC.

A correlation exists between Spitzer colour and mass-loss rate.

The total mass-loss rate from AGB stars in the LMC is quantified.

Abstract

It is still an unresolved problem how much AGB stars can contribute to the overall gas and dust enrichment processes in the interstellar medium within galaxies. We start tackling this problem, by using our test case observational data from the Large Magellanic Cloud (LMC), from which we obtain the global gas and dust budget. The photometric data from the LMC is obtained with the Spitzer Space Telescope. We established an infrared colour classification scheme to select AGB stars, which are based on spectroscopically identified AGB stars. We further confirm a correlation between the Spitzer colour and mass-loss rate, which leads to a measurement of the total mass-loss rate from the entire AGB population in the LMC. Indeed, AGB stars are an important gas and dust source.