A Grid of Models for Asymptotic Giant Branch Stars: Calculating The Dust Return to the Large Magellanic Cloud
Sundar SRINIVASAN
IAP Paris
Résumé :
We have calculated luminosities and mass-loss rates for thousands of Large
Magellanic Cloud (LMC) O- and C-rich asymptotic giant branch (AGB) star
candidates identified in the Spitzer SAGE (Surveying the Agents of a
Galaxy's Evolution) survey by fitting synthetic photometry derived from
the GRAMS (Grid of Models for Red supergiants and AGB Stars) grid. The
SAGE IRAC+MIPS24 data combined with UBVIJHKs photometry furnish
information over the entire wavelength range relevant to AGB sars. SAGE
detects all the significant mass-losing sources in the LMC. Fits to the
spectral energy distributions (SEDs) confirm their AGB status and provide
us with luminosities and mas-loss rates for the entire LMC AGB population.
We use this information to calculate the total AGB dust budget and compare
our results to previous empirical studies that used mid-IR excesses and
colors. AGB stars are among the most significant contributors of dust to
the interstellar medium; our study will thus provide a better
understanding of the role of AGB dust production in the LMC.
