Seminars

Radiation-Hydrodynamics at the Edge: The Lives and Deaths of the Most Massive Stars in our Universe

In many astrophysical situations radiation plays a key role for the dynamics of the system (AGN accretion disks and outflows, supernovae, the first stars, etc.). After first highlighting some quite general issues when dealing with such radiation-hydrodynamic (RHD) flows, this talk zooms in on luminous stars with masses many times that of our Sun. We will show how strong radiation forces there lead to highly structured atmospheres as well as powerful stellar outflows, and how such winds critically shape the violent life-cycles of these stars, all the way from their formation to their death. 
A few recent research-results from our group that will be discussed involve: i) how new blue-star wind models may call for a revision of the ‘standard’ formation-channel for classical Wolf-Rayet (WR) stars (as well as have consequences for formation of high-mass stellar black holes); ii) how new red-star mass loss models may tentatively explain some observed properties of Type II-P/L supernovae, and iii) how our first (and brand new) 3D-RHD models of massive helium-stars lead to a natural transition between WR stars and the hot, stripped sub-dwarfs believed to be the products of binary evolution.   
And indeed, we highlight how these results have all (more or less) been derived from the same overarching research question: “how to get blown away by starlight?”