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Related papers: Leptonic CP violation from a vector-like lepton

200 papers

We study the possible magnitudes of CP and lepton-number-violating quantities in specific GUT models of massive neutrinos with different Abelian flavour groups, taking into account experimental constraints and requiring successful…

High Energy Physics - Phenomenology · Physics 2009-09-11 John Ellis , Mario E. Gomez , Smaragda Lola

We uncover an interesting phenomenon that neutrino flavor transformation in slowly varying matter density imitates almost exactly that of vacuum neutrino oscillation under suitably chosen experimental parameters. It allows us to have…

High Energy Physics - Phenomenology · Physics 2009-10-31 Hisakazu Minakata , Hiroshi Nunokawa

We present a model which employs $CP\times Z_3$ symmetries where quark mixing and charged leptons masses are explained by following some texture. To achieve neutrino mass and mixing, we write a non-renormalizable Lagrangian using type-II…

High Energy Physics - Phenomenology · Physics 2022-07-13 Joy Ganguly

We investigate the prospects for detection of lepton flavour violation in sparticle production and decays at a Linear Collider (LC), in models guided by neutrino oscillation data. We consider both slepton pair production and sleptons…

High Energy Physics - Phenomenology · Physics 2015-05-28 E. Carquin , J. Ellis , M. E. Gomez , S. Lola

Considering the $\mu$-$\tau$ symmetry, we discuss a direct linkage between phases of flavor neutrino masses and leptonic CP violation by determining three eigenvectors associated with ${\rm\bf M}=M^\dagger_\nu M_\nu$ for a complex flavor…

High Energy Physics - Phenomenology · Physics 2008-11-26 Teppei Baba , Masaki Yasue

If the massive neutrinos are identified to be the Majorana particles via a convincing measurement of the neutrinoless double beta (0\nu\beta\beta) decay, how to determine the Majorana CP-violating phases in the 3 x 3 lepton flavor mixing…

High Energy Physics - Phenomenology · Physics 2013-08-09 Zhi-zhong Xing , Ye-Ling Zhou

We discuss in detail the constraints on partial compositeness coming from flavour and CP violation in the leptonic sector. In a first part we present a formulation of partial compositeness in terms of a flavour symmetry group and a set of…

High Energy Physics - Phenomenology · Physics 2016-01-27 Ferruccio Feruglio , Paride Paradisi , Andrea Pattori

Supersymmetric theories generally have new flavor and CP violation sources in the squark and slepton mass matrices. They will contribute to the lepton flavor violation processes, such as $\mu \to e \gamma$, which can be probed far below the…

High Energy Physics - Phenomenology · Physics 2009-10-30 Hsin-Chia Cheng

We consider a class of models predicting new heavy neutral fermionic states, whose mixing with the light neutrinos can be naturally significant and produce observable effects below the threshold for their production. We update the indirect…

High Energy Physics - Phenomenology · Physics 2016-09-01 D. Tommasini , G. Barenboim , G. Bernabeu , C. Jarlskog

Soft supersymmetry breaking terms involving heavy singlet sneutrinos provide new sources of lepton number violation and of CP violation. In addition to the CP violation in mixing, investigated previously, we find that `soft leptogenesis'…

High Energy Physics - Phenomenology · Physics 2008-11-26 Yuval Grossman , Tamar Kashti , Yosef Nir , Esteban Roulet

I discuss some theoretical aspects of how to observe leptonic CP violation. It is divided into two parts, one for CP violation due to Majorana, and the other more conventional leptonic Kobayashi-Maskawa (KM) phases. In the first part, I…

High Energy Physics - Phenomenology · Physics 2008-11-26 Hisakazu Minakata

Some models of leptogenesis involve a nearly-degenerate pair of heavy Majorana neutrinos $N_{1,2}$ whose masses can be small, $O({\rm GeV})$. There can be heavy-light neutrino mixing parametrized by $|B_{\ell N}|^2 = 10^{-5}$, which leads…

High Energy Physics - Phenomenology · Physics 2021-04-27 David London

A possible interplay between the two terms of the general type-II seesaw formula is exercised which leads to the generation of nonzero $\theta_{13}$. The specific flavor structure of the model, guided by the $A_4 \times Z_4 \times Z_3$…

High Energy Physics - Phenomenology · Physics 2016-01-13 Biswajit Karmakar , Arunansu Sil

We rewrite the Yukawa interactions of the standard model in terms of flavour-dependent vacuum structure to address the family mass hierarchy and CP violation in both the quark sector and lepton sector. It is realized for the first time that…

High Energy Physics - Phenomenology · Physics 2022-01-17 Ying Zhang

CP4 3HDM is a curious version of the three-Higgs-doublet model built upon a CP symmetry of order 4 (dubbed CP4). When extended to fermions, CP4 leads to unusually tight correlations between the scalar and Yukawa sectors and induces…

High Energy Physics - Phenomenology · Physics 2026-01-28 Bei Liu , Igor P. Ivanov

Constrained flavor violation is a recent proposal for predicting the down-quark Yukawa matrix in terms of those for up quarks and charged leptons. We study the viability of CFV with respect to its predictions for the lepton mass ratios,…

High Energy Physics - Phenomenology · Physics 2016-04-13 James M. Cline , Alfonso Diaz-Furlong , Jing Ren

We analyse the interplay of generalised CP transformations and the non-Abelian discrete group $T^{\prime}$ and use the semi-direct product $G_f= T^{\prime}\rtimes H_{\text{CP}}$, as family symmetry acting in the lepton sector. The family…

High Energy Physics - Phenomenology · Physics 2014-05-20 Ivan Girardi , Aurora Meroni , S. T. Petcov , Martin Spinrath

We consider the MSSM with see-saw mechanism of neutrino mass generation and soft SUSY breaking with flavour-universal boundary conditions at the GUT scale, in which the lepton flavour violating (LFV) decays \mu\to e + \gamma, \tau\to \mu +…

High Energy Physics - Phenomenology · Physics 2014-11-18 S. T. Petcov , T. Shindou , Y. Takanishi

We propose that leptonic CP violation arises from a breaking of the mu-tau exchange symmetry in the neutrino mass matrix which in turn is indicated by the near maximal atmospheric neutrino mixing and the near zero \theta_{13}. We find that…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. N. Mohapatra , W. Rodejohann

Charged lepton flavour violation is reappraised in the context of supersymmetric see-saw mechanism. It is pointed out that a non-trivial flavour structure of right-handed neutrinos, whose effect has been thus far less studied, can give rise…

High Energy Physics - Phenomenology · Physics 2014-05-14 Jae-hyeon Park