The most complete sample of red supergiants in 14 galaxies of the Local Group

Red supergiants (RSGs) are massive Population I stars, the major progenitor of supernovae. With strong stellar wind, RSGs are an important source of interstellar dust, in particularly for the high redshift galaxies in the early universe when low-mass stars have not evolved to the asymptotic giant branch phase. However, the estimation of contribution of RSGs to interstellar dust suffers large uncertainty mainly because there is no complete sample of RSGs in any galaxy. This talk will present our recent work on building a complete sample of RSGs in fourteen galaxies of the Local Group using a novel method based on the near-infrared color-color diagram to remove the foreground dwarf stars for relatively distant galaxy. Meanwhile, the Gaia astrometric information is taken as the criteria for the nearby Magellanic Clouds. The sample is almost complete for about 12 galaxies, though Sextans A and B are too far for the UKIRT observation to cover the faint end of RSGs there. The talk will also discuss the potential use of the RSG sample in investigating the stellar model for massive stars and the galactic stellar populations.

Biwei Jiang (BNU)
Join Zoom Meeting Meeting ID: 820 4626 7592 Passcode: 342641
Ke Wang
Thursday, April 28, 2022 - 3:30PM to Thursday, April 28, 2022 - 4:30PM
Professor at the Department of Astronomy, Beijing Normal University. She graduated from the Department of Astronomy of Beijing Normal University in 1989, and obtained a Ph.D. in Science from the Graduate University for Advanced Studies in Japan in 1997. She has dedicated to the study of interstellar medium and stellar astronomy. Her main research topics include: circumstellar medium around evolved stars, light variation of red supergiants in the local group of galaxies, interstellar extinction law from infrared to ultraviolet, extinction and dust of supernova remnants.