Estimation of the dust mass-loss rates from AGB stars in the Fornax and Sagittarius dwarf Spheroidal galaxies

Lagadec, Eric; Zijlstra, Albert A.; Matsuura, Mikako; Whitelock, Patricia A.; van Loon, Jacco Th.

Estimation of the dust mass-loss rates from AGB stars in the Fornax and Sagittarius dwarf Spheroidal galaxies

Authors

Lagadec, Eric

Zijlstra, Albert A.

Matsuura, Mikako

Whitelock, Patricia A.

van Loon, Jacco Th.

Description

To study the effect of metallicity on the mass-loss of AGB stars, we have conducted mid-infrared photometric measurements of AGB stars in the Sagittarius and Fornax Dwarf Spheroidal Galaxies ([Fe/H]=-1.1 and -1.3) with the 10-micron camera of VISIR at the VLT. These observations combined with previous near-infrared photometric measurements allow us to estimate mass-loss rates in these galaxies. We show here that the observed AGB display dust-driven mass-loss. Dust mass-loss rate are found to be in the range 0.2$\times10^{-10}-1.3\times10^{-8}$ M$_{\odot}$yr$^{-1}$ for the observed AGB stars in SgrD and around 5$\times10^{-11}$ M$_{\odot}$yr$^{-1}$ for the observed star in Fornax.
5 pages, 1 figures, To appear in ASP conf Ser, "Why Galaxies Care About AGB Stars"