Citation:
Date Published:
April 1, 1995Abstract:
We show that seeds for quasar black holes could have originated from theinitial cosmological collapse of overdense regions with unusually smallrotation. The gas in these rare regions collapses into a compact diskthat shrinks on a short viscous timescale. Using an analytical model, wecalculate the low-pin tail of the probability distribution of angularmomenta for objects that collapse out of a Gaussian random field ofinitial density peturbations. The population of low-spin systems issignificant for any viable power spectrum of primordial densityperturbations. Most objects from just above the cosmological Jeans massapproximately 105 solar mass at high redshifts z greater thanand approximately 10. In the standard cold dark matter cosmology, thecomoving density of 106-7 solar mass objects with viscousevolution times shorter than approximately 106-7 years isapproximately 10-3(h/0.5)3/cubic Mpc, comparableto the local density of bright galaxies. The seed black holes tend toreside within larger mass systems that collapse later and supply the gasneeded for the bright quasar activity.