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Leptogenesis in flavor models with type I and II seesaws Aristizabal Sierra, Diego ; ; in Nuclear Physics B (2012), 858 In type I seesaw models with flavor symmetries accounting for the lepton mixing angles the CP asymmetry in right-handed neutrino decays vanishes in the limit in which the mixing pattern is exact. We study ... [more ▼] In type I seesaw models with flavor symmetries accounting for the lepton mixing angles the CP asymmetry in right-handed neutrino decays vanishes in the limit in which the mixing pattern is exact. We study the implications that additional degrees of freedom from type II seesaw may have for leptogenesis in such a limit. We classify in a model independent way the possible realizations of type I and II seesaw schemes, differentiating between classes in which leptogenesis is viable or not. We point out that even with the interplay of type I and II seesaws there are generic classes of minimal models in which the CP asymmetry vanishes. Finally we analyze the generation of the lepton asymmetry by solving the corresponding kinetic equations in the general case of a mild hierarchy between the light right-handed neutrino and the scalar triplet masses. We identify the possible scenarios in which leptogenesis can take place. [less ▲] Detailed reference viewed: 25 (8 ULg)Tri-Bimaximal Lepton Mixing and Leptogenesis Aristizabal Sierra, Diego ; ; et al in Nuclear Physics B (2010), 827 In models with flavour symmetries added to the gauge group of the Standard Model the CP-violating asymmetry necessary for leptogenesis may be related with low-energy parameters. A particular case of ... [more ▼] In models with flavour symmetries added to the gauge group of the Standard Model the CP-violating asymmetry necessary for leptogenesis may be related with low-energy parameters. A particular case of interest is when the flavour symmetry produces exact Tri/Bi-maximal lepton mixing leading to a vanishing CP-violating asymmetry. In this paper we present a model-independent discussion that confirms this always occurs for unflavoured leptogenesis in type I see-saw scenarios, noting however that Tri/Bi-maximal mixing does not imply a vanishing asymmetry in general scenarios where there is interplay between type I and other see-saws. We also consider a specific model where the exact Tri/Bi-maximal mixing is lifted by corrections that can be parametrised by a small number of degrees of freedom and analyse in detail the existing link between low and high-energy parameters—focusing on how the deviations from Tri/Bi-maximal are connected to the parameters governing leptogenesis. [less ▲] Detailed reference viewed: 6 (2 ULg)t-channel unitarity and photon cross sections Cudell, Jean-René ; ; in Nuclear Physics B (2004), 682(1-2), 391-420 We analyse the consequences of t-channel unitarity for the photon hadronic cross sections. We show that gamma((*))p and gamma((*))gamma((*)) elastic amplitudes must include the complex-j plane ... [more ▼] We analyse the consequences of t-channel unitarity for the photon hadronic cross sections. We show that gamma((*))p and gamma((*))gamma((*)) elastic amplitudes must include the complex-j plane singularities associated with hadronic elastic amplitudes, and give the characteristics of possible new singularities. We also show that several different models of hadronic total cross sections can be used to predict the LEP data from the HERA measurements. (C) 2004 Elsevier B.V. All rights reserved. [less ▲] Detailed reference viewed: 17 (4 ULg)Fermi motion and quark off-shellness in elastic vector- meson production ; Cudell, Jean-René in Nuclear Physics B (1999), B545 Detailed reference viewed: 18 (2 ULg)The BFKL pomeron: Can it be detected? Cudell, Jean-René ; ; in Nuclear Physics B (1996), 482 Detailed reference viewed: 3 (1 ULg)The quark propagator from the Dyson-Schwinger equations: (I). The chiral solution Cudell, Jean-René ; ; in Nuclear Physics B (1995), 440 Detailed reference viewed: 4 (3 ULg)A Consistent next-to-leading order QCD calculation of hadronic diffractive scattering Cudell, Jean-René ; in Nuclear Physics B (1994), 420 Detailed reference viewed: 11 (4 ULg)Theory and phenomenology of the gluon propagator from the Dyson-Schwinger equation in QCD Cudell, Jean-René ; in Nuclear Physics B (1991), 359 A QCD-inspired model for exclusive Vector meson production in deep inelastic scattering Cudell, Jean-René in Nuclear Physics B (1990), 336 Detailed reference viewed: 7 (3 ULg)Quark and gluon condensates and the small x limit of the nucleon structure functions Cudell, Jean-René ; ; in Nuclear Physics B (1989), 322 Detailed reference viewed: 6 (3 ULg) |
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