Collapsar Accretion and the Gamma-Ray Burst X-Ray Light Curve (2009)
Lindner, Christopher C., Milosavljevic, Milos, Couch, Sean M., Kumar, Pawan
We present axisymmetric hydrodynamical simulations of the long-term accretion of a rotating GRB progenitor star, a "collapsar," onto the central compact object. The simulations were carried out with...
Aspherical Core-Collapse Supernovae in Red Supergiants Powered by Nonrelativistic Jets (2008)
Couch, Sean M., Wheeler, J. Craig, Milosavljevic, Milos
We explore the observational characteristics of jet-driven supernovae by simulating bipolar-jet-driven explosions in a red supergiant progenitor. We present results of four models in which we hold...
Accretion onto Intermediate-Mass Black Holes in Dense Protogalactic Clouds (2008)
Milosavljevic, Milos, Couch, Sean M., Bromm, Volker
We present the first results from two-dimensional simulations of radiatively-efficient accretion of metal-free gas onto intermediate-mass black holes. We fix the shape of the spectral energy...
Accretion onto Seed Black Holes in the First Galaxies (2008)
Milosavljevic, Milos, Bromm, Volker, Couch, Sean M., Oh, S. Peng
The validity of the hypothesis that the massive black holes in high redshift quasars grew from stellar-sized "seeds" is contingent on a seed's ability to double its mass every few ten million years....
Couch, Sean M., Milosavljevic, Milos, Nakar, Ehud
We investigate the interaction of nonthermal ions (protons and nuclei) accelerated in an ultrarelativistic blastwave with the pre-existing magnetic field of the medium into which the blastwave...
Wheeler, J. Craig, Maund, Justyn R., Couch, Sean M.
Based on optical, IR and X-ray studies of Cas A, we propose a geometry for the remnant based on a "jet-induced" scenario with significant systematic departures from axial symmetry. In this model, the...