Magnetorotatioal Collapse of Supermassive Stars: Black Hole Formation and Jets

We perform magnetohydrodynamic simulations in full general relativity of the collapse of radially unstable, uniformly rotating, massive stars to black holes. The stars spin at the mass-shedding limit, account for magnetic fields and obey a $\Gamma$ = 4/3 EOS. The calculations lift the restriction of axisymmetry imposed in previous simulations. Our simulations model the direct collapse of supermassive stars to supermassive BHs ($\geq 10^4 \text{M}_{\odot}$) at high cosmological redshifts, which may explain the appearance of supermassive BHs and quasars by z $\sim$ 7. They also crudely model the collapse of massive Pop III stars to massive BHs, which could power some of the long gamma-ray bursts observed by FERMI and SWIFT at z $\sim$ 6-8. We analyze the properties of the electromagnetic and gravitational wave signatures of these events and discuss the detectability of such multimessenger sources.