Dr. Anna Rosen, NSF and UC Chancellor’s Postdoctoral Fellow
When
Abstract: Massive Stars play an essential role in the Universe. They are rare, yet the mass, energy, and momentum they inject into the interstellar medium (i.e., stellar feedback) with their intense radiation fields, collimated protostellar outflows, and fast, isotropic stellar winds dominate the energetics of star-forming regions and galaxies, which has important implications for both star and galaxy formation. Massive stars form from the gravitational collapse of magnetized, dense, and turbulent molecular gas clumps located within giant molecular clouds (GMCs; Mcl >103 Msun). During their formation, stellar feedback may limit their growth by accretion, and enrich and disrupt their natal environments before they end their lives in violent supernova explosions. To understand these processes, highly-detailed radiation-magnetohydrodynamic (RMHD) simulations are required. In this talk, I will present results from a series of RMHD simulations that model the formation of massive stars and star clusters that include all of the aforementioned feedback processes. I will demonstrate that stellar feedback quenches accretion onto ~30 Msun stars that form in isolation and therefore stars more massive than this must form in regions within giant molecular clouds that are supplied mass via large-scale, high ram-pressure dynamical inflows, in agreement with observations of massive star-forming regions. Additionally, I will discuss the importance of stellar wind feedback in star cluster formation and evolution, including how winds from evolved massive stars enrich the ISM before exploding as supernovae.
*Graduate students will meet with Dr. Rosen for lunch on Tuesday at 12:00 PM (AZ) in room N305.