Leptogenesis and Low Energy CP Violation in Neutrino Physics
| dc.contributor.area | Physics | en_US |
| dc.contributor.author | Pascoli, Silvia | en_US |
| dc.contributor.author | Petcov, Serguey T. | en_US |
| dc.contributor.author | Riotto, Antonio | en_US |
| dc.contributor.department | Elementary Particle Theory | en_US |
| dc.date.accessioned | 2006-12-07T15:48:44Z | en_US |
| dc.date.accessioned | 2011-09-07T20:27:07Z | |
| dc.date.available | 2006-12-07T15:48:44Z | en_US |
| dc.date.available | 2011-09-07T20:27:07Z | |
| dc.date.issued | 2006-12-07T15:48:44Z | en_US |
| dc.description.abstract | Taking into account the recent progress in the understanding of the lepton flavour effects in leptogenesis, we investigate in detail the possibility that the CP-violation necessary for the generation of the baryon asymmetry of the Universe is due exclusively to the Dirac and/or Majorana CP-violating phases in the PMNS neutrino mixing matrix U, and thus is directly related to the low energy CP-violation in the lepton sector (e.g., in neutrino oscillations, etc.). We first derive the conditions of CP-invariance of the neutrino Yukawa couplings lambda in the see-saw Lagrangian, and of the complex orthogonal matrix R in the ``orthogonal'' parametrisation of lambda. We show, e.g. that under certain conditions i) real R and specific CP-conserving values of the Majorana and Dirac phases can imply CP-violation, and ii) purely imaginary R does not necessarily imply breaking of CP-symmetry. We study in detail the case of hierarchical heavy Majorana neutrino mass spectrum, presenting results for three possible types of light neutrino mass spectrum: i) normal hierarchical, ii) inverted hierarchical, and iii) quasi-degenerate. Results in the alternative case of quasi-degenerate in mass heavy Majorana neutrinos, are also derived. The minimal supersymmetric extension of the Standard Theory with right-handed Majorana neutrinos and see-saw mechanism of neutrino mass generation is discussed as well. We illustrate the possible correlations between the baryon asymmetry of the Universe and i) the rephasing invariant J_CP controling the magnitude of CP-violation in neutrino oscillations, or ii) the effective Majorana mass in neutrinoless double beta decay, in the cases when the only source of CP-violation is respectively the Dirac or the Majorana phases in the neutrino mixing matrix. | en_US |
| dc.format.extent | 616870 bytes | en_US |
| dc.format.mimetype | application/pdf | en_US |
| dc.identifier.citation | Nucl. Phys. B 774 (2007) 1-52 | en_US |
| dc.identifier.uri | https://openscience.sissa.it/handle/1963/1900 | en_US |
| dc.language.iso | en_US | en_US |
| dc.relation.ispartofseries | SISSA;71/2006/EP | en_US |
| dc.relation.ispartofseries | arXiv.org;hep-ph/0611338 | en_US |
| dc.relation.uri | 10.1016/j.nuclphysb.2007.02.019 | en_US |
| dc.title | Leptogenesis and Low Energy CP Violation in Neutrino Physics | en_US |
| dc.type | Preprint | en_US |