ABSTRACT
One of the simplest and most attractive mechanisms of baryogenesis [2] is baryogenesis via leptogenesis suggested by Fukugita and Yanagida [3]. In this mechanism is is assumed that the baryon asymmetry has originated from physics in the leptonic sector. Namely, it is assumed that at temperatures well above the electroweak scale, lepton asymmetry was produced, which was then reprocessed into the baryoll asyrnmetry by llonperturbative electroweak effects [4] - sphalerons [5]. According to ref. [3] the lepton asymmetry is generated in out-of-equilibriulll, CP-and lepton number non-conserving decays of heavy Majorana neutrinos (for recent discussions see, e. g., ref. [6] and references therein).
