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arXiv · 0907.3767

Red Supergiants in the Andromeda Galaxy (M31)

Philip Massey·David R. Silva·Emily M. Levesque·Bertrand Plez·Knut A. G. Olsen·Geoffrey C. Clayton·Georges Meynet·Andre Maeder
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Abstract

Red supergiants are a short-lived stage in the evolution of moderately massive stars (10-25Mo), and as such their location in the H-R diagram provides an exacting test of stellar evolutionary models. Since massive star evolution is strongly affected by the amount of mass-loss a star suffers, and since the mass-loss rates depend upon metallicity, it is highly desirable to study the physical properties of these stars in galaxies of various metallicities. Here we identify a sample of red supergiants in M31 (the most metal-rich of the Local Group galaxies) and derive their physical properties by fitting MARCS atmosphere models to moderate resolution optical spectroscopy, and from V-K photometry.

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Philip Massey, David R. Silva, Emily M. Levesque, Bertrand Plez, Knut A. G. Olsen, Geoffrey C. Clayton, Georges Meynet, Andre Maeder. 2009-07-22. Red Supergiants in the Andromeda Galaxy (M31). https://doi.org/10.1088/0004-637x/703/1/420

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