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Related papers: Sum Rules for Leptons

200 papers

We have investigated a flavour model [1] which inspired by small squared-mass difference measured in solar neutrino oscillation experiments and observability in neutrinoless double beta decay experiments. In our model, the $1^{\rm st.}$ and…

High Energy Physics - Phenomenology · Physics 2017-08-23 Hiroyuki Ishida

Flavour models may display a relation between the CP-violating asymmetry for leptogenesis and low-energy parameters. If the flavour symmetry produces an exact mass independent lepton mixing scheme at leading order (with type I see-saw) the…

High Energy Physics - Phenomenology · Physics 2015-05-27 Ivo de Medeiros Varzielas

Heavy singlet neutrinos admit Majorana masses which are not possible for the Standard Model particles. This suggest new possibilities for generating the masses and mixing angles of light neutrinos. We present a model of neutrino physics…

High Energy Physics - Phenomenology · Physics 2008-11-26 Micheal S. Berger , Samuel Santana

In view of the precise measurement of the leptonic mixing angle \theta_{13}, implications of the latest mixing data have been investigated for lepton mass matrices pertaining to Dirac neutrinos.These texture specific lepton mass matrices…

High Energy Physics - Phenomenology · Physics 2014-10-28 Priyanka Fakay , Samandeep Sharma

We suggest two alternative schemes to predict lepton mixing angles as well as $CP$ violating phases from a discrete flavor symmetry group combined with $CP$ symmetry. In the first scenario, the flavor and $CP$ symmetry is broken to the…

High Energy Physics - Phenomenology · Physics 2017-01-25 Jun-Nan Lu , Gui-Jun Ding

We propose to understand the mixing angles and CP-violating phases from the $\Delta(48)$ family symmetry combined with the generalized CP symmetry. A model-independent analysis is performed by scanning all the possible symmetry breaking…

High Energy Physics - Phenomenology · Physics 2015-02-02 Gui-Jun Ding , Ye-Ling Zhou

Leptogenesis is considered in its natural context where Majorana neutrinos fit in a gauge unification scheme and therefore couple to some extra gauge bosons. The masses of some of these gauge bosons are expected to be similar to those of…

High Energy Physics - Phenomenology · Physics 2009-11-10 N. Cosme

We show that there is a minimal discrete symmetry which leads to the extended flavour democracy scenario constraining the Dirac neutrino, the charged lepton and the Majorana neutrino mass term ($M_R$) to be all proportional to the…

High Energy Physics - Phenomenology · Physics 2009-11-07 G. C. Branco , J. I. Silva-Marcos

We produce five flavour models for the lepton sector. All five models fit perfectly well---at the one-sigma level---the existing data on the neutrino mass-squared differences and on the lepton mixing angles. The models are based on the…

High Energy Physics - Phenomenology · Physics 2015-06-15 P. M. Ferreira , L. Lavoura , P. O. Ludl

The fermion mass problem is briefly reviewed. The observed hierarchy of quark and charged lepton masses strongly suggests the existence of an approximately conserved chiral flavour symmetry beyond the Standard Model. It is argued that in…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. D. Froggatt

Using the fact that the neutrino mixing matrix $U = U^\dagger_{e}U_{\nu}$, where $U_{e}$ and $U_{\nu}$ result from the diagonalisation of the charged lepton and neutrino mass matrices, we analyse the sum rules which the Dirac phase $\delta$…

High Energy Physics - Phenomenology · Physics 2015-04-24 I. Girardi , S. T. Petcov , A. V. Titov

Lepton flavor universality is a key prediction of the Standard Model of particle physics and any violation of it immediately indicates the existence of new physics. Given the recent more than $4\sigma$ discrepancy in charged current…

High Energy Physics - Phenomenology · Physics 2026-01-16 Motoi Endo , Syuhei Iguro , Tim Kretz , Satoshi Mishima , Ryoutaro Watanabe

We analyze the structure of quark and lepton mass matrices under the hypothesis that they are determined from a minimum principle applied to a generic potential invariant under the $\left[U(3)\right]^5\otimes {\mathcal O}(3)$ flavor…

High Energy Physics - Phenomenology · Physics 2014-05-23 Rodrigo Alonso

We study mixing of the Dirac neutrinos in the residual symmetries approach. The key difference from the Majorana case is that the Dirac mass matrix may have larger symmetries: $G_\nu=\mathbf{Z}_{n}$ with $n\geq3$. The symmetry group…

High Energy Physics - Phenomenology · Physics 2015-12-02 Arman Esmaili , Alexei Yu. Smirnov

This is a review article about neutrino mass and mixing and flavour model building strategies based on discrete family symmetry. After a pedagogical introduction and overview of the whole of neutrino physics, we focus on the PMNS mixing…

High Energy Physics - Phenomenology · Physics 2016-03-01 Stephen F. King , Christoph Luhn

We propose new lepton-mixing textures that may be enforced through well-defined symmetries in renormalizable models. Each of our textures has four sum rules for the neutrino mass observables. The models are based on the type-I seesaw…

High Energy Physics - Phenomenology · Physics 2019-09-04 D. Jurciukonis , L. Lavoura

Four different neutrino mass sum-rules have been analyzed: these frequently arise in flavor symmetry models based on the groups A_4, S_4 or T', which are often constructed to generate tri-bimaximal mixing. In general, neutrino mass can be…

High Energy Physics - Phenomenology · Physics 2011-07-22 James Barry , Werner Rodejohann

The renormalization effect on a specific ansatz of lepton mass matrices, arising naturally from the breaking of flavor democracy for charged leptons and that of mass degeneracy for light neutrinos, is studied from a superhigh energy scale…

High Energy Physics - Phenomenology · Physics 2009-10-31 Zhi-zhong Xing

We compute and compare the baryon asymmetry of the universe in thermal leptogenesis scenario with and without flavour effects for different neutrino mass models namely degenerate, inverted hierarchical and normal hierarchical models, with…

High Energy Physics - Phenomenology · Physics 2009-11-13 H. Zeen Devi , Amal Kr Sarma , N. Nimai Singh

We perform a detailed study of lepton mixing patterns arising from a scenario with three Majorana neutrinos in which a discrete flavor group Gf=Delta (3 n^2) or Gf=Delta(6 n^2) and a CP symmetry are broken to residual symmetries Ge=Z3 and…

High Energy Physics - Phenomenology · Physics 2015-05-20 C. Hagedorn , A. Meroni , E. Molinaro