B-ball dark matter and baryogenesis

it has been recently suggested that stable, supersymmetric B-balls formed in the early universe could not only be the dark matter at the present epoch, but also be responsible for baryogenesis by their partial evaporation at high temperatures. We reinvestigate the efficiency of B-ball baryogenesis and find it to be limited by the diffusion of baryon number away from the B-balls. Successful baryogenesis may only occur for B-balls with charges Q less than or similar to 10(20)-5 x 10(23), which is close to the observational lower limits on the Q of a significant B-ball dark matter component. We also present some cosmological constraints on the abundances of larger B-balls in the early universe. (C) 2000 Elsevier Science B.V. All rights reserved.