An Odyssey in the Clouds: influential lives of massive stars at low metallicity

• Applicant: Professorin Dr. Lida Oskinova
• Subject Area: Astrophysics and Astronomy
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 443790621

Stars which have a much higher mass than our Sun are rare but influential. They produce energetic radiation and drive strong stellar winds which largely determine the conditions in their cosmic vicinity. At the end of their life-cycles, massive stars collapse and form neutron stars or black holes. This project is devoted to the studies of massive stars in the Small and the Large Magellanic Clouds. These galaxies are the nearby satellites of our own Galaxy, the Milky Way, and can be seen even by the naked eye from the southern hemisphere. Compared to the Milky Way, the matter in the Magellanic Clouds contains significantly less contributions from chemical elements that are heavier than helium. In this respect, Magellanic Clouds resemble the galaxies at much earlier cosmic times. We expect that in such ''metal poor" galaxies some of the key properties of massive stars, such as stellar winds, are very different from those in the Milky Way. Hence the massive stars in Magellanic Clouds follow different, not yet well understood, live journeys. Yet, these are decisive for the galactic evolution, from star formation processes over the chemical enrichment till the masses of the finally remaining black holes, which latterly can be measured through the gravitational waves in case of their merging. To strongly advance the knowledge on massive stars and understand better their influence, we propose an ambitious project based on cutting-edge observations and our state-of-the art models. Soon, the Hubble Space Telescope (HST) will deliver an unprecedented legacy spectroscopic library of massive stars in the Magellanic Clouds. We are well equipped and prepared for immediate work on these data. Furthermore, we have accumulated large amounts of proprietary as well as archival-harvested data from the ESO's Very Large Telescope (VLT). The consistent analyses of the HST and VLT spectra from massive stars in the Magellanic Clouds will take advantage from our stellar atmosphere models ("PoWR"). As the result of this project, we will establish the properties of a significant part of the massive star population in the Magellanic Clouds, and determine their role in shaping the interstellar medium in these galaxies. This unprecedented study will be transformative and deliver comprehensive and modern view on massive stars in metal poor environments.

• DFG Programme: Research Grants