Jarrett L. Johnson, Daniel J. Whalen, Wesley Even, Chris L. Fryer, Alex Heger, Joseph Smidt, Ke-Jung Chen
Supermassive primordial stars are expected to form in a small fraction of massive protogalaxies in the early universe, and are generally conceived of as the progenitors of the seeds of supermassive black holes (BHs) at high redshift. Supermassive stars with masses of ~ 55,000 M_Sun, however, have been found to explode and completely disrupt in a supernova (SN) with an energy of up to ~ 10^55 erg, instead of collapsing to a BH. Such events, roughly 10,000 times more energetic than typical SNe today, would be among the biggest explosions in the history of the universe. We carry out a simulation of such a supermassive star SN in two stages. Using the RAGE radiation hydrodynamics code we first evolve the explosion from the earliest stages, through the breakout of the shock from the surface of the star until the blast wave has propagated out to several parsecs from the explosion site, which lies deep within an atomic cooling dark matter (DM) halo at z ~ 15. Then, using the GADGET cosmological hydrodynamics code we evolve the explosion out to several kiloparsecs from the explosion site, far into the low-density intergalactic medium. The host DM halo, with a total mass of 4 x 10^7 M_Sun, much more massive than typical primordial star-forming halos, is completely evacuated of high density gas after < 10 Myr, although dense metal-enriched gas recollapses into the halo, where it will likely form second-generation stars after > 70 Myr. The ~ 20,000 M_Sun in metals that are released in the explosion are widely distributed, and enrich the dense recollapsing gas to an average metallicity of ~ 0.05 Z_Sun. Such a high level of enrichment suggests that the chemical signature of these supermassive star explosions may have been missed in previous surveys of metal-poor stars.
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http://arxiv.org/abs/1304.4601
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