English
Related papers

Related papers: Softly broken lepton numbers and maximal neutrino …

200 papers

We discuss models where the U(1) symmetries of lepton numbers are responsible for maximal neutrino mixing. We pay particular attention to an extension of the Standard Model with three right-handed neutrino singlets in which we require that…

High Energy Physics - Phenomenology · Physics 2008-11-26 W. Grimus , L. Lavoura

We consider the most general neutrino mass matrix which leads to $\theta_{13} = 0$, and present the formulae needed for obtaining the neutrino masses and mixing parameters in that case. We apply this formalism to a model based on the lepton…

High Energy Physics - Phenomenology · Physics 2011-07-19 W. Grimus , L. Lavoura

In this paper we consider a plausible scenario with conserved lepton number \textbf{$L=L_{e}-L_{\mu}-L_{\tau}$} within the framework of the exact solution of a particular 3-3-1 gauge model. We discuss what are the consequences of conserving…

High Energy Physics - Phenomenology · Physics 2009-02-24 Adrian Palcu

We propose a discrete non-abelian symmetry group which enforces maximal atmospheric neutrino mixing, while $\theta_{13} = 0$ and the solar mixing angle $\theta_{12}$ remains undetermined; without finetuning, $\theta_{12}$ will be large but…

High Energy Physics - Phenomenology · Physics 2015-06-25 W. Grimus , L. Lavoura

We enlarge the lepton sector of the Standard Model by adding to it two right-handed neutrino singlets, and propose a model based on the seesaw mechanism and on the lepton number $\bar L = L_e - L_\mu - L_\tau$. The model is innovative from…

High Energy Physics - Phenomenology · Physics 2009-10-31 L. Lavoura , W. Grimus

We show that both small mixing in the quark sector and large mixing in the lepton sector can be obtained from a simple assumption of universality of Yukawa couplings and the right-handed neutrino Majorana mass matrix in leading order. We…

High Energy Physics - Phenomenology · Physics 2009-11-10 Radovan Dermisek

The PMNS neutrino mixing matrix is given, in general, by the product of two unitary matrices associated with the diagonalization of the charged lepton and neutrino mass matrices, respectively. Assuming that the active flavor neutrinos…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. T. Petcov , W. Rodejohann

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 discuss conditions under which bi-large mixing in the lepton sector is achieved assuming that all Yukawa matrices and the right-handed neutrino mass matrix have the same singular form in the leading order. Due to obvious quark lepton…

High Energy Physics - Phenomenology · Physics 2007-05-23 Radovan Dermisek

The pattern of lepton mixing can emerge from breaking a flavor symmetry in different ways in the neutrino and charged lepton Yukawa sectors. In this framework, we derive the conditions imposed on the mixing matrix by the structure of…

High Energy Physics - Phenomenology · Physics 2013-05-30 D. Hernandez , A. Yu. Smirnov

We discuss a neutrino mass matrix $\mathcal{M}_\nu$ originally found by Babu, Ma, and Valle (BMV) and show that this mass matrix can be characterized by a simple algebraic relation. From this relation it follows that atmospheric neutrino…

High Energy Physics - Phenomenology · Physics 2015-06-25 W. Grimus , L. Lavoura

We show that maximal atmospheric and large solar neutrino mixing can be implemented in SU(5) gauge theories, by making use of the $U(1)_F$ symmetry associated with a suitably defined family number $F$, together with a $\mathbbm{Z}_2$…

High Energy Physics - Phenomenology · Physics 2011-02-01 W. Grimus , L. Lavoura

Recent results from SuperKamiokande and SNO experiments have set severe constraints on possible mixings of a light sterile neutrino, \nu_s, with the three active species required for a simultaneous explanation of the solar, atmospheric and…

High Energy Physics - Phenomenology · Physics 2009-11-07 K. S. Babu , R. N. Mohapatra

Status of the discrete symmetry approach to explanation of the lepton masses and mixing is summarized in view of recent experimental results, in particular, establishing relatively large 1-3 mixing. The lepton mixing can originate from…

High Energy Physics - Phenomenology · Physics 2013-05-22 Alexei Y. Smirnov

In light of the recent neutrino experiment results from Daya Bay and RENO Collaborations, we study phenomenology of neutrino mixing angles in the Type III seesaw model with an discrete $A_4 \times Z_2$ symmetry, whose spontaneously breaking…

High Energy Physics - Phenomenology · Physics 2015-05-27 Y. H. Ahn , C. S. Kim , Sechul Oh

Contrary to the quark mixing matrix, the lepton mixing matrix could be symmetric. We study the phenomenological consequences of this possibility. In particular, we find that symmetry would imply that |U_{e3}| is larger than 0.16, i.e.,…

High Energy Physics - Phenomenology · Physics 2008-11-26 Kathrin A. Hochmuth , Werner Rodejohann

Assuming three light neutrinos are Majorana particles, we propose mass matrix ansatz for the charged leptons and Majorana neutrinos with family symmetry $S_{3} $ broken into $S_{1}$ and $S_{2}$, respectively. Each matrix has three…

High Energy Physics - Phenomenology · Physics 2009-10-30 Kyungsik Kang , Sin Kyu Kang , Jihn E. Kim , Pyungwon Ko

Using the type-II seesaw mechanism with three Higgs doublets phi_alpha (alpha = e, mu, tau) and four Higgs triplets, we build a model for lepton mixing based on a 384-element horizontal symmetry group, generated by the permutation group S_3…

High Energy Physics - Phenomenology · Physics 2008-11-26 W. Grimus , L. Lavoura

We analyze the leptonic sector in the left-right symmetric model dressed with a $(Z_{2})^{3}$ discrete symmetry which realizes, after weak spontaneous breaking, a small broken $\mu\lra\tau$ symmetry that is suggested to explain observable…

High Energy Physics - Phenomenology · Physics 2014-11-20 Juan Carlos Gómez-Izquierdo , Abdel Pérez-Lorenzana

Freedom from global anomalies in the presence of a local SU(2)_H horizontal symmetry under which right handed charged leptons transform nontrivially requires that there be at least two right handed neutrinos with masses of order of the…

High Energy Physics - Phenomenology · Physics 2014-11-17 R. Kuchimanchi , R. N. Mohapatra
‹ Prev 1 2 3 10 Next ›