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Related papers: Leptonic Unitarity Triangles in Matter

200 papers

In the light of the recent LHC data, we study precision tests sensitive to the violation of lepton universality, in particular the violation of unitarity in neutrino mixing. Keeping all data we find no satisfatory fit, even allowing for…

High Energy Physics - Phenomenology · Physics 2014-05-07 Lorenzo Basso , Oliver Fischer , Jochum J. van der Bij

Starting from the symmetry of lepton flavor democracy, we propose and discuss a simple pattern for the mass generation and flavor mixing of the charged leptons and neutrinos. The three neutrino masses are nearly degenerate, and the flavor…

High Energy Physics - Phenomenology · Physics 2009-10-28 H. Fritzsch , Z. Z Xing

We discuss leptonic mixing and CP violation at low and high energies, emphasizing possible connections between leptogenesis and CP violation at low energies, in the context of lepton flavour models. Furthermore we analyse weak basis…

High Energy Physics - Phenomenology · Physics 2009-11-10 Gustavo C. Branco , M. N. Rebelo

The corrections to neutrino mixing parameters in the presence of matter of constant density are calculated systematically as series expansions in terms of the mass hierarchy $\dm{21}/\dm{31}$. The parameter mapping obtained is then used to…

High Energy Physics - Phenomenology · Physics 2014-11-17 Martin Freund

Encouraged by the latest SNO results, we consider the lepton mixing matrix in the approximation that the nu_2 mass eigenstate is trimaximally (democratically) mixed. This suggests a new parameterization of the remaining mixing degrees of…

High Energy Physics - Phenomenology · Physics 2011-09-29 James D. Bjorken , P. F. Harrison , W. G. Scott

We consider a class of models of neutrino mixing with $S_4$ flavour symmetry and generalised CP symmetry, broken to $Z_2$ and $Z_2 \times {\rm CP}$ residual symmetries in the charged lepton and neutrino sectors, respectively. In this…

High Energy Physics - Phenomenology · Physics 2018-03-30 J. T. Penedo , S. T. Petcov , A. V. Titov

Neutrino oscillations are well established and the relevant parameters determined with good precision, except for the CP phase, in terms of a unitary lepton mixing matrix. Seesaw extensions of the Standard Model predict unitarity deviations…

High Energy Physics - Phenomenology · Physics 2016-04-08 F. J. Escrihuela , D. V. Forero , O. G. Miranda , M. Tortola , J. W. F. Valle

The CP violation required in leptogenesis may have different origin, but in an effective theory they all are related to the rephasing invariant CP violating measure in the mixing matrix of the leptonic sector. We point out that the maximum…

High Energy Physics - Phenomenology · Physics 2011-09-16 Yong Liu , Utpal Sarkar

New heavy neutral leptons lead to non-unitary effects in models for neutrino masses. Such effects could represent a sign of new physics beyond the Standard Model, leading to observable deviations in neutrino oscillation experiments, lepton…

High Energy Physics - Phenomenology · Physics 2024-08-26 Jesús Miguel Celestino-Ramírez , G. Hernández-Tomé , O. G. Miranda , Eduardo Peinado

Some theories of new physics accounting for neutrino masses can give rise to a low-energy non-unitary leptonic mixing matrix. It is shown that the CP-asymmetries in the $\nu_\mu\to \nu_\tau$ channel are an excellent probe of such new…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Lopez-Pavon

In this talk I review the present status of neutrino masses and mixing and some of their implications for particle physics phenomenology. I first discuss the minimum extension of the Standard Model of particle physics required to…

High Energy Physics - Phenomenology · Physics 2009-11-10 M. C. Gonzalez-Garcia

We study a neutrino mass model based on $S_4$ flavor symmetry which accommodates lepton mass, mixing with non-zero $\theta_{13}$ and CP violation phase. The spontaneous symmetry breaking in the model is imposed to obtain the realistic…

High Energy Physics - Phenomenology · Physics 2016-04-20 V. V. Vien

We propose a novel origin for the disparity between quark and lepton flavor mixing based on the refractive nature of neutrino masses. We postulate that the fundamental mixing in both the quark and lepton sectors is CKM-like, together with…

High Energy Physics - Phenomenology · Physics 2026-01-22 Susobhan Chattopadhyay , Yuber F. Perez-Gonzalez , Manibrata Sen

We stress that specific texture zeros of lepton mass matrices, which might dynamically arise from a new kind of flavor symmetry, can help us to establish simple and testable relations between the lepton flavor mixing parameters and lepton…

High Energy Physics - Phenomenology · Physics 2016-12-07 Zhi-zhong Xing

We consider a class of models of neutrino mixing with $S_4$ lepton flavour symmetry combined with a generalised CP symmetry, which are broken to residual $Z_2$ and $Z_2 \times H^\nu_{\rm CP}$ symmetries in the charged lepton and neutrino…

High Energy Physics - Phenomenology · Physics 2017-12-07 J. T. Penedo , S. T. Petcov , A. V. Titov

We calculate the rephasing invariants of CP and T violation in a favorable parametrization of the 4x4 lepton flavor mixing matrix. Their relations with the CP- and T-violating asymmetries in neutrino oscillations are derived, and the matter…

High Energy Physics - Phenomenology · Physics 2009-11-07 Wan-lei Guo , Zhi-zhong Xing

We discuss the use of the CP asymmetry parameter (Acp) as a possible observable of CP violation in the leptonic sector. In order to do this, we study for a wide range of values of L/E the behavior of this asymmetry for the corresponding…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. M. Gago , V. Pleitez , R. Zukanovich Funchal

A low energy non-unitary leptonic mixing matrix is a generic feature of many extensions of the Standard Model. In such a case, the task of future precision neutrino oscillation experiments is more ambitious than measuring the three mixing…

High Energy Physics - Phenomenology · Physics 2009-09-02 Stefan Antusch , Mattias Blennow , Enrique Fernandez-Martinez , Jacobo Lopez-Pavon

Leptonic mixing patterns are usually extracted on the basis of groups or algebraic structures. In this paper, we introduce an alternative geometric method to study the correlations between the leptonic mixing parameters. At the 3$\sigma$…

High Energy Physics - Phenomenology · Physics 2023-02-28 Ding-Hui Xu , Shu-Jun Rong

We propose an $A_4$ extension of the Standard Model with a Lepton Quarticity symmetry correlating dark matter stability with the Dirac nature of neutrinos. The flavor symmetry predicts (i) a generalized bottom-tau mass relation involving…

High Energy Physics - Phenomenology · Physics 2017-09-13 Salvador Centelles Chuliá , Rahul Srivastava , José W. F. Valle