Abstract
Recent simulations of the formation of the first luminous objects in the universe predict isolated very massive stars to form in dark matter halos with virial temperatures large enough to allow significant amounts of molecular hydrogen to form. We construct a semianalytic model based on Press-Schechter formalism and calibrate the minimum halo mass that may form a primordial star with the results from extensive adaptive mesh refinement simulations. The model also includes star formation in objects with virial temperatures in excess of 10,000 K. The free parameters are tuned to match the optical depth measurements by the WMAP satellite. The models explicitly include the negative feedback of the destruction of molecular hydrogen by a soft UV background that is computed self-consistently. We predict high-redshift supernova rates as one of the most promising tools to test the current scenario of primordial star formation. The supernova rate from primordial stars peaks at redshifts of ~20. Using an analytic model for the luminosities of pair-instability supernovae, we predict observable magnitudes and discuss possible observational strategies. Such supernovae would release enough metals corresponding to a uniform enrichment to a few hundred thousand solar. If some of these stars produce gamma-ray bursts, our rates will be directly applicable to understanding the anticipated results from the Swift satellite. This study highlights the great potential of the James Webb Space Telescope in probing cosmic structure at redshifts greater than 15.
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