scholarly journals Predicting CP violation in deviation from tri-bimaximal mixing of neutrinos

2015 ◽  
Vol 30 (01) ◽  
pp. 1550002 ◽  
Author(s):  
Yusuke Shimizu ◽  
Morimitsu Tanimoto ◽  
Kei Yamamoto
Keyword(s):  
Cp Violation ◽  
The Other ◽  
Cabibbo Angle ◽  
Normal Hierarchy ◽  
Inverted Hierarchy ◽  
Mixing Angles ◽  
Lepton Flavor ◽  
Flavor Mixing ◽  
Mixing Patterns ◽  
Charged Leptons

We study the CP violation in the deviation from the tri-bimaximal (TBM) mixing of neutrinos. We examine nontrivial relations among the mixing angles and the CP violating Dirac phase in the typical four cases of the deviation from the TBM. The first two cases are derived by the additional rotation of the 2-3 or 1-3 generations of neutrinos in the TBM basis. The other two cases are given by the additional rotation of the 1-3 or 1-2 generations of charged leptons with the TBM neutrinos. These four cases predict different relations among three mixing angles and the CP violating Dirac phase. The rotation of the 2-3 generations of neutrinos in the TBM basis predicts sin2θ12< 1/3, and the CP violating Dirac phase to be ±(0.09π–0.76π) for NH (±(0.15π–0.73π) for IH) depending on sin2θ23. The rotation of the 1-3 generations of neutrinos in the TBM basis gives sin2θ12> 1/3. The CP violating Dirac phase is not constrained by the input of the present experimental data. For the case of the 1-3 and 1-2 rotations of charged leptons in the TBM basis, the CP violating Dirac phase is predicted in ±(0.35π–0.60π) depending on sin2θ12for both normal hierarchy (NH) and inverted hierarchy (IH) cases. We also discuss the specific case that θ13is related with the Cabibbo angle λ such as [Formula: see text], in which the maximal CP violation is preferred. The CP violating Dirac phase can distinguish the lepton flavor mixing patterns at T2K and NOνA experiments in the future.

NEUTRINOS: LOOKING FORWARD TO THE FUTURE

2007 ◽  
Vol 16 (05) ◽  
pp. 1313-1329
Author(s):  
HISAKAZU MINAKATA
Keyword(s):  
Cp Violation ◽  
Neutrino Mass ◽  
Mass Hierarchy ◽  
Future Prospects ◽  
Neutrino Mass Hierarchy ◽  
Lepton Flavor ◽  
Mixing Parameters ◽  
Wide Range ◽  
Flavor Mixing ◽  
Mass Pattern

I discuss some aspects of future prospects of the experimental exploration of the unknowns in the neutrino mass pattern and the lepton flavor mixing. I start from measuring θ13 by reactors and accelerators as a prerequisite for proceeding to search for leptonic CP violation. I then discuss how CP violation can be uncovered, and how the neutrino mass hierarchy can be determined. I do these by resolving so called the "parameter degeneracy" which is required anyway if one wants to seek precision measurement of the lepton mixing parameters. As a concrete setting for resolving the degeneracy I use the Tokai-to-Kamioka-Korea two detector complex which receives neutrino superbeam from J-PARC, which is sometimes called as "T2KK". It is shown that T2KK is able to resolve all the eight-fold parameter degeneracy in a wide range of the lepton mixing parameters. Some alternative ways of measuring the unknowns are also briefly mentioned.

scholarly journals Lepton-flavor-violating decays of the SM-like Higgs boson $h\rightarrow e_ie_j$, and $e_i \rightarrow e_j\, \gamma $ in a flipped 3-3-1 model

2020 ◽  
Vol 2020 (4) ◽  
Author(s):  
T T Hong ◽  
H T Hung ◽  
H H Phuong ◽  
L T T Phuong ◽  
L T Hue
Keyword(s):  
Higgs Boson ◽  
Branching Ratio ◽  
High Energy ◽  
Branching Ratios ◽  
The Other ◽  
Experimental Limit ◽  
Lepton Flavor ◽  
The Standard Model ◽  
Charged Leptons ◽  
O 10

Abstract In the framework of the flipped 3-3-1 model introduced recently [R. M. Fonseca and M. Hirsch, J. High Energy Phys. 1608, 003 (2016)], the lepton-flavor-violating (LFV) decay $\mu \rightarrow 3e$ was predicted to have a large branching ratio (Br) close to the recent experimental limit. We will show that the Br of LFV decays of the standard-model-like (SM-like) Higgs boson decays (LFVHD) Br$(h\rightarrow e_ae_b)$ may also be large. Namely, Br$(h\rightarrow \mu\tau,e\tau)$ can reach values of $\mathcal{O}(10^{-4}){-}\mathcal{O}(10^{-5})$, which will reach the upcoming experimental sensitivities. On the other hand, for LFV decays of charged leptons (cLFV) $(e_b\rightarrow e_a\gamma)$, the branching ratios are well below experimental bounds.

scholarly journals Quark mass hierarchy and flavor mixing puzzles

2014 ◽  
Vol 29 (30) ◽  
pp. 1430067 ◽  
Author(s):  
Zhi-Zhong Xing
Keyword(s):  
Cp Violation ◽  
Electric Charge ◽  
Particle Physics ◽  
Quark Mass ◽  
Mass Hierarchy ◽  
Quark Masses ◽  
Lepton Flavor ◽  
Quark Flavor ◽  
Flavor Mixing ◽  
Highly Correlated

The fact that quarks of the same electric charge possess a mass hierarchy is a big puzzle in particle physics, and it must be highly correlated with the hierarchy of quark flavor mixing. This chapter is intended to provide a brief description of some important issues regarding quark masses, flavor mixing and CP-violation. A comparison between the salient features of quark and lepton flavor mixing structures is also made.

scholarly journals FLAVOR MIXING AND CP VIOLATION OF MASSIVE NEUTRINOS

2004 ◽  
Vol 19 (01) ◽  
pp. 1-79 ◽  
Author(s):  
ZHI-ZHONG XING
Keyword(s):  
Cp Violation ◽  
Phenomenological Study ◽  
Double Beta Decay ◽  
Seesaw Mechanism ◽  
Lepton Flavor ◽  
Long Baseline ◽  
Mixing Parameters ◽  
Mass Matrices ◽  
Flavor Mixing ◽  
Massive Neutrinos

We present an overview of recent progress in the phenomenological study of neutrino masses, lepton flavor mixing and CP violation. We concentrate on the model-independent properties of massive neutrinos, both in vacuum and in matter. Current experimental constraints on the neutrino mass spectrum and the lepton flavor mixing parameters are summarized. The Dirac- and Majorana-like phases of CP violation, which are associated respectively with the long-baseline neutrino oscillations and the neutrinoless double beta decay, are discussed in detail. The seesaw mechanism, the leptogenesis scenario and the strategies to construct lepton mass matrices are briefly described. The features of flavor mixing between one sterile neutrino and three active neutrinos are also explored.

scholarly journals Modulus τ linking leptonic CP violation to baryon asymmetry in A4 modular invariant flavor model

2021 ◽  
Vol 2021 (7) ◽  
Author(s):  
Hiroshi Okada ◽  
Yusuke Shimizu ◽  
Morimitsu Tanimoto ◽  
Takahiro Yoshida
Keyword(s):  
Cp Violation ◽  
Effective Mass ◽  
Vacuum Expectation ◽  
Vacuum Expectation Value ◽  
Baryon Asymmetry ◽  
Neutrino Masses ◽  
Normal Hierarchy ◽  
Modular Invariant ◽  
Mixing Angles ◽  
Expectation Value

Abstract We propose an A4 modular invariant flavor model of leptons, in which both CP and modular symmetries are broken spontaneously by the vacuum expectation value of the modulus τ. The value of the modulus τ is restricted by the observed lepton mixing angles and lepton masses for the normal hierarchy of neutrino masses. The predictive Dirac CP phase δCP is in the ranges [0°, 50°], [170°, 175°] and [280°, 360°] for Re [τ] < 0, and [0°, 80°], [185°, 190°] and [310°, 360°] for Re [τ] > 0. The sum of three neutrino masses is predicted in [60, 84] meV, and the effective mass for the 0νββ decay is in [0.003, 3] meV. The modulus τ links the Dirac CP phase to the cosmological baryon asymmetry (BAU) via the leptogenesis. Due to the strong wash-out effect, the predictive baryon asymmetry YB can be at most the same order of the observed value. Then, the lightest right-handed neutrino mass is restricted in the range of M1 = [1.5, 6.5] × 1013 GeV. We find the correlation between the predictive YB and the Dirac CP phase δCP. Only two predictive δCP ranges, [5°, 40°] (Re [τ] > 0) and [320°, 355°] (Re [τ] < 0) are consistent with the BAU.

scholarly journals Charged Lepton Masses as a Possible CPV Source

2021 ◽  
Vol 8 (2) ◽  
pp. 161-168
Author(s):  
O. Félix-Beltrán ◽  
J. E. Barradas-Guevara J. E. Barradas-Guevara ◽  
F. González-Canales
Keyword(s):  
Cp Violation ◽  
Neutrino Oscillation ◽  
Charged Lepton ◽  
Mass Matrix ◽  
Independent Study ◽  
Double Beta Decay ◽  
Flavor Mixing ◽  
Minimum Number ◽  
Two Phases ◽  
Charged Leptons

We realize a model-independent study of the so-called Tri-Bi-Maximal pattern of leptonic flavor mixing. Different charged lepton mass matrix textures are studied. In particular, we are interested in those textures with a minimum number of parameters and that are able to reproduce the current experimental data on neutrino oscillation. The textures studied here form an equivalent class with two texture zeros. We obtain a Tri-Bi-Maximal pattern deviation in terms of the charged leptons masses, leading to a reactor angle and three CP violation phases non-zero. These lastest are one CP violation phase Dirac-like and two phases Majorana-like. Also, we can test the phenomenological implications of the numerical values obtained for the mixing angles and CP violation phases, on the neutrinoless double beta decay, and in the present and upcoming experiments on long-base neutrino oscillation, such as T2K, NOvA, and DUNE.

scholarly journals FLAVOR MIXING, QUARK MASSES, NEUTRINO MASSES AND NEUTRINO OSCILLATIONS

2009 ◽  
Vol 24 (18n19) ◽  
pp. 3354-3358 ◽  
Author(s):  
H. FRITZSCH
Keyword(s):  
Neutrino Masses ◽  
Mixing Angle ◽  
Mixing Angles ◽  
Quark Masses ◽  
Mass Matrices ◽  
Mass Ratios ◽  
Flavor Mixing ◽  
Eigen Values ◽  
Charged Leptons ◽  
The Masses

We study a model for the mass matrices of the quarks and leptons. Two of the three flavor mixing angles of the quarks can be calculated in terms of the quark mass ratios. They agree very well with the experiments. We are able to relate the mass eigen values of the charged leptons and of the neutrinos to the mixing angles and can predict the masses of the neutrinos. We find a normal hierarchy -the masses are 0.004 eV, 0.01 eV and 0.05 eV. The atmospheric mixing angle is given by the mass ratios of the charged leptons and the neutrinos. We find 38 degrees, consistent with the experiments. The mixing element, connecting the first neutrino with the electron, is found to be 0.05.

scholarly journals Radiative neutrino masses, lepton flavor mixing and muon g − 2 in a leptoquark model

2021 ◽  
Vol 2021 (7) ◽  
Author(s):  
Di Zhang
Keyword(s):  
Neutrino Mass ◽  
Yukawa Coupling ◽  
Mass Matrix ◽  
Radiative Decays ◽  
Neutrino Masses ◽  
Reflection Symmetry ◽  
Lepton Flavor ◽  
Flavor Mixing ◽  
Charged Leptons ◽  
Scalar Leptoquarks

Abstract We propose a leptoquark model with two scalar leptoquarks $$ {S}_1\left(\overline{3},1,\frac{1}{3}\right) $$ S 1 3 ¯ 1 1 3 and $$ {\tilde{R}}_2\left(3,2,\frac{1}{6}\right) $$ R ˜ 2 3 2 1 6 to give a combined explanation of neutrino masses, lepton flavor mixing and the anomaly of muon g − 2, satisfying the constraints from the radiative decays of charged leptons. The neutrino masses are generated via one-loop corrections resulting from a mixing between S1 and $$ {\tilde{R}}_2 $$ R ˜ 2 . With a set of specific textures for the leptoquark Yukawa coupling matrices, the neutrino mass matrix possesses an approximate μ-τ reflection symmetry with (Mν)ee = 0 only in favor of the normal neutrino mass ordering. We show that this model can successfully explain the anomaly of muon g − 2 and current experimental neutrino oscillation data under the constraints from the radiative decays of charged leptons.

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