Lepton-mediated electroweak baryogenesis
We investigate the impact of the tau and bottom Yukawa couplings on the transport dynamics for electroweak baryogenesis in supersymmetric extensions of the standard model. Although it has generally been assumed in the literature that all Yukawa interactions except those involving the top quark are negligible, we find that the tau and bottom Yukawa interaction rates are too fast to be neglected. We identify an illustrative "lepton-mediated electroweak baryogenesis" scenario in which the baryon asymmetry is induced mainly through the presence of a left-handed leptonic charge. We derive analytic formulas for the computation of the baryon asymmetry that, in light of these effects, are qualitatively different from those in the established literature. In this scenario, for fixed CP-violating phases, the baryon asymmetry has opposite sign compared to that calculated using established formulas.
Additional Information© 2010 The American Physical Society. Received 31 July 2009; published 4 March 2010. This work was supported in part by Department of Energy Contract Nos. DE-FG02-08ER41531 and DE-FG02-95ER40896, and the Wisconsin Alumni Research Foundation.
Published - Chung2010p9872Phys_Rev_D.pdf