BARYON PRODUCTION BY PRIMORDIAL BLACK-HOLES

The evaporation of primordial black holes (PBH's) by the Hawking process can produce an excess of baryons over anti-baryons. Assuming a power-law form of the initial mass spectrum of PBH's and taking into account the observational constraints on that spectrum we calculate the baryon excess produced. We find that if the spectrum is steep (α{greater-than or approximate}3.5) or cut off for masses above ∼ 109 g, the observed baryon/photon ratio of ∼ 10-9 can be produced by PBH evaporations. © 1979.