English

Flavour Matters in Leptogenesis

High Energy Physics - Phenomenology 2009-11-11 v4

Abstract

We give analytic approximations to the baryon asymmetry produced by thermal leptogenesis with hierarchical right-handed neutrinos. Our calculation includes flavour-dependent washout processes and CP violation in scattering, and neglects gauge interactions and finite temperature corrections. Our approximate formulae depend upon the three CP asymmetries in the individual lepton flavours as well as on three flavour-dependent efficiency factors. We show that the commonly used expressions for the lepton asymmetry, which depend on the total CP asymmetry and one single efficiency factor, may fail to reproduce the correct lepton asymmetry in a number of cases. We illustrate the importance of using the flavour-dependent formulae in the context of a two right-handed neutrino model.

Keywords

Cite

@article{arxiv.hep-ph/0605281,
  title  = {Flavour Matters in Leptogenesis},
  author = {A. Abada and S. Davidson and A. Ibarra and F. -X. Josse-Michaux and M. Losada and A. Riotto},
  journal= {arXiv preprint arXiv:hep-ph/0605281},
  year   = {2009}
}

Comments

Additional typos corrected (in particular, the plots and captions now agree)

R2 v1 2026-07-22T14:08:53.854Z