Date: 07.03.2023

Dominique Meyer (Potsdam)

The circumstellar medium of massive stars

Abstract:
Stars more massive than our Sun, by at least a factor of ten, are rare but seminal objects in galaxies such as our Milky Way. Their powerful radiation, stellar winds, and explosive deaths are dominant engines driving the cycle of matter in the interstellar medium, by ionizing and chemically enriching it, inducing turbulence, and producing cosmic rays. Additionally, a significant fraction of them is ejected from their parent cluster and run supersonically through the interstellar medium. In this talk, we will take a journey throughout the lives of massive stars, from their evolved to defunct evolutionary phases. We will employ state-of-art numerical models to discover how the morphology of the interstellar medium is sculptured by massive stars and what it tells us about the stellar feedback in galaxies. Particularly, we will (i) present simulations I have tailored to the surroundings of evolved massive stars like the red supergiant Betelgeuse, to constrain its past evolution. Finally, we will (ii) explore what the asymmetries in non-thermal remnants left behind massive stars which died in a supernova explosion, like the Cygnus Loop nebula, tell us about their past lives. Finally, we will see how the past history of massive stars affects the development of the pulsar wind nebula. These elaborated simulations provide us with accurate predictive synthetic images and precise forecasts confirmed by observations, which are insights into the fascinating circumstellar medium of massive stars.