Horizontal symmetry: masses and mixing angles of quarks and leptons of different generations; neutrino mass and neutrino oscillation

1985 ◽  
Vol 28 (1) ◽  
pp. 104-105 ◽  
Author(s):  
Z G Berezhiani ◽  
Dzh L Chkareuli
Keyword(s):  
Neutrino Oscillation ◽  
Neutrino Mass ◽  
Mixing Angles ◽  
Horizontal Symmetry

scholarly journals Effects of Leptonic Nonunitarity on Lepton Flavor Violation, Neutrino Oscillation, Leptogenesis, and Lightest Neutrino Mass

2018 ◽  
Vol 2018 ◽  
pp. 1-10
Author(s):  
Gayatri Ghosh ◽  
Kalpana Bora
Keyword(s):  
Neutrino Oscillation ◽  
Neutrino Mass ◽  
Type I ◽  
Lepton Flavor Violation ◽  
Neutrino Mixing ◽  
Inverted Hierarchy ◽  
Planck Data ◽  
Mixing Angles ◽  
Lepton Flavor ◽  
Mixing Matrix

Neutrino physics is a mature branch of science with all the three neutrino mixing angles and two mass squared differences determined with high precision. In spite of several experimental verifications of neutrino oscillations and precise measurements of two mass squared differences and the three mixing angles, the unitarity of the leptonic mixing matrix is not yet established, leaving room for the presence of small nonunitarity effects. Deriving the bounds on these nonunitarity parameters from existing experimental constraints, on cLFV decays such as μ→eγ, μ→τγ, and τ→eγ, we study their effects on the generation of baryon asymmetry through leptogenesis and neutrino oscillation probabilities. We consider a model where see-saw is extended by an additional singlet S which is very light but can give rise to nonunitarity effects without affecting the form on see-saw formula. We do a parameter scan of a minimal see-saw model in a type I see-saw framework satisfying the Planck data on baryon to photon ratio of the Universe, which lies in the interval 5.8×10-10<YB<6.6×10-10(BBN). We predict values of lightest neutrino mass and Dirac and Majorana CP-violating phases δCP, α, and β, for normal hierarchy and inverted hierarchy for one-flavor leptogenesis. It is worth mentioning that all these four quantities are unknown yet, and future experiments will be measuring them.

Multiscalar B − L model with Σ(18) symmetry for neutrino mass and mixing

2021 ◽  
pp. 2150132
Author(s):  
V. V. Vien
Keyword(s):  
Neutrino Oscillation ◽  
Neutrino Mass ◽  
Tree Level ◽  
Type I ◽  
Normal Ordering ◽  
Seesaw Mechanism ◽  
Mixing Angles ◽  
Neutrino Mass And Mixing ◽  
Text Model ◽  
Best Fit

We construct a non-renormalizable [Formula: see text] model based on [Formula: see text] symmetry, whereby, neutrino mass ordering and the tiny neutrino masses are explained at tree level via type I seesaw mechanism. The model can reproduce the recent observed neutrino oscillation data in which neutrino oscillation parameters including three mixing angles [Formula: see text], Dirac CP phase plus neutrino squared-mass splittings [Formula: see text] get the best-fit values for both Normal ordering (NO) and Inverted ordering (IO). The Majorana phases are predicted to be [Formula: see text] for NO, [Formula: see text] for IO and [Formula: see text] for both NH and IO. The sum of neutrino mass and the effective neutrino mass are, respectively, predicted to be [Formula: see text] for NO while [Formula: see text] for IO and [Formula: see text] for NO while [Formula: see text] for IO which are well compatible with the most recent experimental constraints.

scholarly journals CONSTRAINTS OF MIXING ANGLES FROM NEUTRINO OSCILLATION EXPERIMENTS AND NEUTRINOLESS DOUBLE BETA DECAY

1998 ◽  
Vol 13 (28) ◽  
pp. 2279-2287 ◽  
Author(s):  
TAKESHI FUKUYAMA ◽  
KOUICHI MATSUDA ◽  
HIROYUKI NISHIURA
Keyword(s):  
Beta Decay ◽  
Neutrino Oscillation ◽  
Neutrino Mass ◽  
Neutrinoless Double Beta Decay ◽  
Double Beta Decay ◽  
Neutrino Masses ◽  
Mixing Angles

From the analyses of the recent data of neutrino oscillation experiments (especially the CHOOZ and the super-Kamiokande experiments), we discuss how these data affect the neutrinoless double beta decay ((ββ)0ν) rate and vice versa assuming that neutrinos are Majorana particles. For the case of m1~m2≪m3 (mi are neutrino masses), we obtain, from the data of the CHOOZ and super-Kamiokande, 0.28 ≲ sin 2θ23≲ 0.76 and sin 2θ13≲ 0.05. Combining the latter constraint with the analysis of the "averaged" neutrino mass <mν> appeared in (ββ)0ν, we find that [Formula: see text], which leads to the constraint on <mν> as <mν> ≲ 0.05m3 + (1 - 0.05)m2. For the case of m1≪m2~ m3, we find that the data of neutrino oscillation experiments and (ββ)0ν imply the following constraints of mixing angles: if 0.95m3≲ <mν> < m3, [Formula: see text]. If <mν> ≲ 0.95m3, [Formula: see text] and [Formula: see text].

NEUTRINO MASSES, OSCILLATIONS, AND TESTS WITH FUTURE SUPERBEAMS AND A NEUTRINO FACTORY

2003 ◽  
Vol 18 (22) ◽  
pp. 3921-3933 ◽  
Author(s):  
M. LINDNER
Keyword(s):  
Cp Violation ◽  
Neutrino Oscillation ◽  
Neutrino Masses ◽  
Neutrino Factory ◽  
Mixing Angles ◽  
Long Baseline

Future long baseline neutrino oscillation (LBL) setups are discussed and the remarkable potential for very precise measurements of mass splittings, mixing angles, MSW effects, the sign of Δm2 and leptonic CP violation is shown. Furthermore we discuss the sensitivity improvements which can be obatined by combining the planned JHF-Superkamiokande and the proposed NuMI off-axis experiment.

scholarly journals NEUTRINO OSCILLATIONS AND THE EXACT PARITY MODEL

1994 ◽  
Vol 09 (02) ◽  
pp. 169-179 ◽  
Author(s):  
R. FOOT
Keyword(s):  
Neutrino Mass ◽  
General Result ◽  
Neutrino Oscillations ◽  
Mass Matrix ◽  
Atmospheric Neutrino ◽  
Solar Neutrinos ◽  
Specific Model ◽  
Neutrino Mixing ◽  
Mixing Angles ◽  
Significant Deficit

We re-examine neutrino oscillations in exact parity models. Previously it was shown in a specific model that large neutrino mixing angles result. We show here that this is a general result of neutrino mixing in exact parity models provided that the neutrino mass matrix is real. In this case, the effects of neutrino mixing in exact parity models is such that the probability of a given weak eigenstate remaining in that eigenstate averages to less than half when averaged over many oscillations. This result is interesting in view of the accumulating evidence for a significant deficit in the number of solar neutrinos. It may also be of relevance to the atmospheric neutrino anomaly.

NEUTRINO MASS SPECULATION ON THE EVENTS OF NEUTRINOS FROM THE SUPERNOVA LMC 1987 A

1987 ◽  
Vol 02 (12) ◽  
pp. 905-911 ◽  
Author(s):  
H. HUZITA
Keyword(s):  
Neutrino Oscillation ◽  
Neutrino Mass ◽  
Energy Threshold ◽  
Energy Correlation ◽  
Neutrino Oscillation Experiment ◽  
Oscillation Experiment

The interactions of neutrinos from the supernova LMC 1987 A by Kamiokande II apparatus have a curious character. Time to energy correlation has two separated groups. If this is not completely by chance each group corresponds to non zero neutrino mass 3.4 ± 0.6 and 23. ± 4. eV . The latter is not consistent with the results of neutrino oscillation experiment. IMB data are not contrary to the Kamiokas considering IMB's higher energy threshold.

scholarly journals Perturbation to TBM mixing and its phenomenological implications

2016 ◽  
Vol 31 (38) ◽  
pp. 1650207 ◽  
Author(s):  
M. Sruthilaya ◽  
Srinu Gollu
Keyword(s):  
Neutrino Mass ◽  
Mass Formula ◽  
Electron Neutrino ◽  
Leading Order ◽  
Mixing Angle ◽  
Mixing Angles ◽  
Neutrino Sector ◽  
Upper Limit ◽  
Mixing Matrix ◽  
Reactor Mixing

To accommodate the recently observed nonzero reactor mixing angle [Formula: see text], we consider the lepton mixing matrix as tri-bimaximal mixing (TBM) form in the leading order along with a perturbation in neutrino sector. The perturbation is taken to be a rotation in 23 plane followed by a rotation in 13 plane, i.e. [Formula: see text]. We obtain the allowed values of the parameters [Formula: see text], [Formula: see text] and [Formula: see text], which can accommodate all the observed mixing angles consistently and calculate the phenomenological observables such as the Dirac CP violating phase [Formula: see text], Jarlskog invariant [Formula: see text], effective Majorana mass [Formula: see text] and [Formula: see text], the electron neutrino mass. We find that [Formula: see text] can take any values between [Formula: see text] and [Formula: see text] and [Formula: see text] always comes below its experimental upper limit.

scholarly journals Latest Results from the T2K Neutrino Experiment

Universe ◽  
2019 ◽  
Vol 5 (1) ◽  
pp. 21
Author(s):  
Dean Karlen ◽  
on behalf of the TtwoK Collaboration
Keyword(s):  
Cp Violation ◽  
Neutrino Oscillation ◽  
Neutrino Mass ◽  
Electron Neutrino ◽  
Muon Neutrino ◽  
Neutrino Experiment ◽  
Long Baseline ◽  
Neutrino Oscillation Experiment ◽  
Electron Neutrino Appearance ◽  
Oscillation Experiment

The T2K long baseline neutrino oscillation experiment measures muon neutrino disappearance and electron neutrino appearance in accelerator-produced neutrino and anti-neutrino beams. This presentation reports on the analysis of our data from an exposure of 2 . 6 × 10 21 protons on target. Results for oscillation parameters, including the CP violation parameter and neutrino mass ordering, are shown.

scholarly journals θ13, μτ SYMMETRY BREAKING AND NEUTRINO YUKAWA TEXTURES

2013 ◽  
Vol 28 (24) ◽  
pp. 1350118 ◽  
Author(s):  
BISWAJIT ADHIKARY ◽  
AMBAR GHOSAL ◽  
PROBIR ROY
Keyword(s):  
Symmetry Breaking ◽  
Neutrino Mass ◽  
Charged Lepton ◽  
Heavy Neutrino ◽  
Type I ◽  
Mixing Angles ◽  
Order Analysis ◽  
A Value ◽  
Mass Matrices ◽  
Best Fit

Within the type-I seesaw and in the basis where charged lepton and heavy neutrino mass matrices are real and diagonal, μτ symmetric four and three zero neutrino Yukawa textures are perturbed by lowest order μτ symmetry breaking terms. These perturbations are taken to be the most general ones for those textures. For quite small values of those symmetry breaking parameters, permitting a lowest order analysis, current best-fit ranges of neutrino mass squared differences and mixing angles are shown to be accommodable, including a value of θ13 in the observed range, provided all the light neutrinos have an inverted mass ordering.

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