Cosmic backgrounds due to the formation of the first generation of supermassive black holes

Abstract

The statistics of black holes and their masses strongly suggests that their mass distribution has a cut-off towards lower masses near 3 × 106 M&sun;. This is consistent with a classical formation mechanism from the agglomeration of the first massive stars in the universe. However, when the masses of the stars approach 106 M&sun;, the stars become unstable and collapse, possibly forming the first generation of cosmological black holes. Here, we speculate that the claimed detection of an isotropic radio background may constitute evidence of the formation of these first supermassive black holes, since their data are compatible in spectrum and intensity with synchrotron emission from the remnants. The model proposed fulfils all observational conditions for the background, in terms of single-source strength, number of sources, far-infrared and gamma-ray emission. The observed high-energy neutrino flux is consistent with our calculations in flux and spectrum. The proposal described in this paper may also explain the early formation and growth of massive bulge-less disc galaxies as derived from the massive, gaseous shell formed during the explosion prior to the formation of a supermassive black hole.