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DURING THE FINAL PHASES OF STELLAR EVOLUTION ASYMPTOTIC GIANT BRANCH STARS (AGB;<10 MSUN) BECOME PRODIGIOUS DUST PRODUCERS AND MAY BE THE DOMINANT STELLAR SOURCE OF INTERSTELLAR MEDIUM (ISM) DUST. IN OUR OWN SOLAR SYSTEM ABOUT 90% OF PRESOLAR GRAINS SHOW EVIDENCE FOR AN AGB ORIGIN. THIS IS AT ODDS WITH MODELS OF AGB DUST INPUT THAT SUGGEST THAT AGB STARS MAY ONLY CONTRIBUTE AROUND 2% OF THE ISM DUST IN THE SOLAR NEIGHBORHOOD WITH ISM GRAIN GROWTH AND SUPERNOVAE (SNE) RESPONSIBLE FOR THE REMAINING DUST. NEW RESULTS FROM NITTLER ET AL. (2018) SUGGEST THAT PRESOLAR GRAINS ARE ENRICHED BY MATERIAL THAT MAY HAVE COME FROM A NEARBY ELECTRONCAPTURE SN. THE PROGENITORS OF THESE SNE ARE VERY RARE SUPER-AGB STARS (8-10 MSUN) SUGGESTING THAT OUR SOLAR SYSTEM MAY BE UNUSUAL. DIRECT MEASUREMENTS OF THE WIDE-SCALE DUST INPUT IN A STAR-FORMING SOLAR-METALLICITY ENVIRONMENT DO NOT EXIST BECAUSE MILKY WAY MEASUREMENTS ARE COMPLICATED BY DISTANCE UNCERTAINTIES THAT GAIA CANNOT RESOLVE BECAUSE IT OPERATES AT OPTICAL WAVELENGTHS. AS SUCH COMPREHENSIVE DUST BUDGET SURVEYS HAVE ONLY BEEN POSSIBLE IN THE MAGELLANIC CLOUDS WHERE THE LOW METALLICITY (20-50% SOLAR) SIGNIFICANTLY AFFECTS THE AGB DUST INPUT RENDERING THEM POOR PROXIES FOR THE SOLAR NEIGHBORHOOD. WE PROPOSE TO USE ARCHIVAL SPITZER DATA OF THE NEARBY ANDROMEDA GALAXY (M31) TO IDENTIFY AND CHARACTERIZE DUST PRODUCING STARS. M31 IS THE ONLY MASSIVE L* METAL-RICH GALAXY NEARBY ENOUGH TO RESOLVE STARS PROVIDING A WINDOW INTO THE PHYSICAL PROCESSES THAT SHAPED BOTH OUR OWN HOME IN THE MILKY WAY AND THE ENVIRONMENTS OF MASSIVE GALAXIES THAT DOMINATE REDSHIFT SURVEYS. PRELIMINARY ANALYSIS SHOWS THAT WE CAN IDENTIFY THE DUST PRODUCING STARS IN THE SPITZER DATA WHEN LEVERAGING INFORMATION FROM THE PANCHROMATIC HUBBLE ANDROMEDA TREASURY (PHAT) WHICH IMAGED 1/3 OF M31'S DISK FROM THE UV TO THE NEAR-IR. WHEN COMBINED THE SPITZER DATA REVEAL THE DUSTIEST OBJECTS AND CAN BE USED TO ESTIMATE A GLOBAL DUST INPUT. WE WILL COMPARE THESE RESULTS TO THE ISM DUST MASS DERIVED FROM ARCHIVAL HERSCHEL DATA TO PRODUCE THE FIRST GLOBAL DUST BUDGET FOR A METAL-RICH ENVIRONMENT.

$332,459FY2020National Aeronautics and Space AdministrationNASA

Association Of Universities For Research In Astronomy, Inc., Tucson AZ

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