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Title: Charged lepton decays l{sub i}{yields}l{sub j}+{gamma}, leptogenesis CP-violating parameters and Majorana phases

Journal Article · · Physical Review. D, Particles Fields
;  [1]
  1. Scuola Internazionale Superiore di Studi Avanzati, and Istituto Nazionale di Fisica Nucleare, I-34014 Trieste (Italy)

We analyze the dependence of the rates of the LFV charged-lepton decays {mu}{yields}e+{gamma}, {tau}{yields}e+{gamma}, {tau}{yields}{mu}+{gamma} (l{sub i}{yields}l{sub j}+{gamma}) and their ratios, predicted in the class of SUSY theories with see-saw mechanism of {nu}-mass generation and soft SUSY breaking with universal boundary conditions at the GUT scale, on the Majorana CP-violation phases in the PMNS neutrino mixing matrix and the ''leptogenesis'' CP-violating (CPV) parameters. The case of quasidegenerate in mass heavy Majorana neutrinos is considered. The analysis is performed for normal hierarchical (NH), inverted hierarchical (IH) and quasidegenerate (QD) light neutrino mass spectra. We show, in particular, that for NH and IH {nu}-mass spectrum and negligible lightest neutrino mass, all three l{sub i}{yields}l{sub j}+{gamma} decay branching ratios, BR(l{sub i}{yields}l{sub j}+{gamma}), depend on one Majorana phase, one leptogenesis CPV parameter and on the 3-neutrino oscillation parameters; if the CHOOZ mixing angle {theta}{sub 13} is sufficiently large, they depend on the Dirac CPV phase in the PMNS matrix. The ''double ratios'' R(21/31){approx}BR({mu}{yields}e+{gamma})/BR({tau}{yields}e+{gamma}) and R(21/32){approx}BR({mu}{yields}e+{gamma})/BR({tau}{yields}{mu}+{gamma}) are determined by these parameters. The same Majorana phase enters into the NH and IH expressions for the effective Majorana mass in neutrinoless double beta decay, <m>.

OSTI ID:
20871291
Journal Information:
Physical Review. D, Particles Fields, Vol. 74, Issue 7; Other Information: DOI: 10.1103/PhysRevD.74.073006; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
Country of Publication:
United States
Language:
English