Astronomy Colloquium / Spring 2007

April 25th

Prof Andrew Mac Fadyen

New York University

Collapsars: Gamma Ray Bursts from Massive Stars

I will discuss the collapsar model for the explosion of massive rotating stars which form black holes at their centers and subsequently accrete rapidly for tens of seconds. I will then discuss the formation of magnetic towers in these stars from a black hole accretion disk or a rapidly rotating neutron star. I will present high-resolution numerical simulations of relativistic explosions in massive stars and discuss whether we always expect these explosions to produce bright supernovae as well as how GRB progenitors are affected by metallicity.