Calculation of the Emergent Spectrum and Observation of Primordial Black Holes

Abstract

We calculate the emergent spectrum of microscopic black holes, taking into account the proposition that a quark and gluon photosphere forms around the black hole. We find that the limit on the average universal density of black holes is not significantly affected by the photosphere; however, we also find that gamma ray satellites such as EGRET and GLAST are well suited to look for nearby black holes out to a distance on the order of 0.3 parsec, and conclude that if black holes are clustered in our Galaxy by a factor of order ${10}^8$ they may be directly detectable.