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Related papers: Democratic-type neutrino mass matrix

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We present a three-loop model of neutrino mass whose most-general Lagrangian possesses a softly-broken accidental $Z_2$ symmetry. In the limit that a single parameter vanishes, $\lambda\rightarrow0$, the $Z_2$ symmetry becomes exact and the…

High Energy Physics - Phenomenology · Physics 2014-11-04 Amine Ahriche , Kristian L. McDonald , Salah Nasri

The observed neutrino mixing, having a near maximal atmospheric neutrino mixing angle and a large solar mixing angle, is close to tri-bi-maximal, putting leptonic mixing in contrast with the small mixing of the quark sector. We discuss a…

High Energy Physics - Phenomenology · Physics 2008-11-26 I. de Medeiros Varzielas

Based on a neutrino mass matrix model in which a 2-3 symmetry is only broken by a phase parameter, it is investigated how the lepton mixing matrix can deviate from the so-called tribimaximal mixing under a condition that CP is maximally…

High Energy Physics - Phenomenology · Physics 2014-11-20 Yoshio Koide , Hiroyuki Nishiura

We present a supersymmetric model with the flavour symmetry S4 x Z3 and a CP symmetry which are broken to a Z3 subgroup of the flavour symmetry in the charged lepton sector and to Z2 x CP (x Z3) in the neutrino one at leading order. This…

High Energy Physics - Phenomenology · Physics 2014-02-18 Ferruccio Feruglio , Claudia Hagedorn , Robert Ziegler

In this paper, we derive in a novel approach the possible textures of neutrino mass matrix that can lead us to maximal atmospheric mixing angle and Dirac CP phase which are consistent with the current neutrino oscillation data. A total of…

High Energy Physics - Phenomenology · Physics 2018-11-14 Zhi-Cheng Liu , Chong-Xing Yue , Zhen-hua Zhao

We present a systematic study of 400 combinations of the charged lepton and neutrino mass matrices with six vanishing entries or texture zeros. Only 24 of them, which can be classified into a few distinct categories, are found to be…

High Energy Physics - Phenomenology · Physics 2011-09-13 Shun Zhou , Zhi-zhong Xing

We further study the "complementary" Ansatz, Tr$(M_\nu)$=0, for a prediagonal light Majorana type neutrino mass matrix. Previously, this was studied for the CP conserving case and the case where the two Majorana type CP violating phases…

High Energy Physics - Phenomenology · Physics 2009-11-10 Samina S. Masood , Salah Nasri , Joseph Schechter

Assuming a type-I seesaw mechanism for neutrino mass generation and invoking a baryogengesis via leptogenesis scenario, we consider a reasonable hierarchical structure for Dirac neutrino mass matrix, similar to up-type quark mass matrix.…

High Energy Physics - Phenomenology · Physics 2018-11-14 Franco Buccella , Damiano F. G. Fiorillo , Gennaro Miele , Stefano Morisi , Ofelia Pisanti , Pietro Santorelli

Non-zero leptonic CP phases in the neutrino sector are clear evidence for physics beyond the Standard Model and have many implications in particle physics and cosmology. Some clues to maximal Dirac CP violation $\delta_{CP}=3\pi/2$ are…

High Energy Physics - Phenomenology · Physics 2017-10-17 Ying Zhang

We propose two schemes for the lepton mixing matrix $U = U_l^\dagger U_\nu$, where $U = U_l$ refers to the charged sector, and $U_\nu$ denotes the neutrino diagonalization matrix. We assume $U_\nu$ to be CP conserving and its three angles…

High Energy Physics - Phenomenology · Physics 2019-04-18 Peng Chen , Gui-Jun Ding , Rahul Srivastava , José W. F. Valle

I attempt to quantify how far from maximal one should expect the atmospheric mixing angle to be given a neutrino mass-matrix that leads, at zeroth order, to a nu_3 mass-eigenstate that is 0% nu_e, 50% nu_mu, and 50% nu_tau. This is done by…

High Energy Physics - Phenomenology · Physics 2009-11-10 Andre de Gouvea

In this work we study examples of hierarchical neutrino mass matrices inspired by family symmetries, compatible with experiments on neutrino oscillations, and for which there is a connection among the low energy CP violation phase…

High Energy Physics - Phenomenology · Physics 2009-11-10 L. Velasco-Sevilla

CP violation in the lepton sector, and other aspects of neutrino physics, are studied within a high scale supersymmetry model. In addition to the sneutrino vacuum expectation values (VEVs), the heavy vector-like triplet also contributes to…

High Energy Physics - Phenomenology · Physics 2020-10-14 Ying-Ke Lei , Chun Liu

The latest experimental progress have established three kinds of neutrino oscillations with three mixing angles measured to rather high precision. There is still one parameter, i.e., the CP violating phase, missing in the neutrino mixing…

High Energy Physics - Phenomenology · Physics 2012-06-22 Xinyi Zhang , Bo-Qiang Ma

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

We consider the most general supersymmetric model with minimal particle content and an additional discrete Z_3 symmetry (instead of R-parity), which allows lepton number violating terms and results in non-zero Majorana neutrino masses. We…

High Energy Physics - Phenomenology · Physics 2009-11-11 Athanasios Dedes , Steven Rimmer , Janusz Rosiek

We propose a texture of three generation Majorana-type neutrino mass matrix in terms of only two parameters which gives rise to nearly bi-maximal mixing angles. We also demonstrate an explicit realization of such type of neutrino…

High Energy Physics - Phenomenology · Physics 2009-12-30 Ambar Ghosal

The fermion masses and mixing angles are fitted using only 3 free parameters in a non-supersymmetric extension of the Standard Model, with new approximately conserved chiral gauge quantum numbers broken by a set of Higgs fields. The…

High Energy Physics - Phenomenology · Physics 2009-10-30 C. D. Froggatt , M. Gibson , H. B. Nielsen , D. J. Smith

In this Letter we show that the evidence for neutrino oscillations from the Super-Kamiokande atmospheric neutrino data fully determines the 3x3 neutrino-oscillations mixing matrix and predicts an energy independent solar neutrino deficit at…

High Energy Physics - Phenomenology · Physics 2011-02-07 Ion Stancu

We reconstruct the neutrino mass matrix in the flavor basis, using all available experimental data on neutrino oscillations. Majorana nature of neutrinos, normal mass hierarchy (ordering) and validity of the LMA MSW solution of the solar…

High Energy Physics - Phenomenology · Physics 2010-04-05 Michele Frigerio , Alexei Yu. Smirnov
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