A New Mechanism For Baryogenesis Living Through Electroweak Era

Abstract

We present a new mechanism for baryogenesis by introducing a heavy vector-like SU(2)_W singlet quark(s) with Q_{em}=2/3 quark U or Q_{em}=-1/3 quark D. The lifetime of the heavy quark is assumed to be in the range 2 \times 10^{-11}s < t < 1s. Being SU(2)_W singlet, it survives the electroweak phase transition era. It mixes with SU(2)_W doublet quarks with tiny mixing angles to satisfy the FCNC constraints, where a simple Z_2 symmetry is suggested for realizing this scheme. The heavy quark asymmetry is generated in analogy with the old GUT scenario.

10 pages, typos corrected, the washout rate by sphaleron corrected and new bound from the decay using 4 fermi interaction added