scholarly journals NEUTRINO OSCILLATIONS: FROM STANDARD AND NON-STANDARD VIEWPOINTS

2011 ◽  
Vol 01 ◽  
pp. 291-296 ◽  
Author(s):  
BO-QIANG MA
Keyword(s):  
Standard Model ◽  
Neutrino Oscillations ◽  
Oscillation Amplitude ◽  
Lorentz Violation ◽  
Neutrino Energy ◽  
Effective Field ◽  
Neutrino Mixing ◽  
Neutrino Flavor ◽  
Mixing Matrix ◽  
Pmns Matrix

In the standard model of neutrino oscillations, the neutrino flavor states are mixtures of mass-eigenstates, and the phenomena are well described by the neutrino mixing matrix, i.e., the PMNS matrix. I review the recent progress on parametrization of the neutrino mixing matrix. Besides that I also discuss on the possibility to describe the neutrino oscillations by a non-standard model in which the neutrino mixing is caused by the Lorentz violation (LV) contribution in the effective field theory for LV. We assume that neutrinos are massless and that neutrino flavor states are mixing states of energy eigenstates. In our calculation the neutrino mixing parts depend on LV parameters and neutrino energy. The oscillation amplitude varies with the neutrino energy, thus neutrino experiments with energy dependence may test and constrain the Lorentz violation scenario for neutrino oscillation.

A Clifford algebra-based grand unification program of gravity and the Standard Model: a review study

2014 ◽  
Vol 92 (12) ◽  
pp. 1501-1527 ◽  
Author(s):  
Carlos Castro
Keyword(s):  
Standard Model ◽  
Geometric Probability ◽  
Coupling Constants ◽  
Grand Unified Theory ◽  
Neutrino Mixing ◽  
Yang Mills ◽  
Bounded Complex ◽  
The Standard Model ◽  
Mixing Matrix ◽  
Homogeneous Domains

A Clifford Cl(5, C) unified gauge field theory formulation of conformal gravity and U(4) × U(4) × U(4) Yang–Mills in 4D, is reviewed along with its implications for the Pati–Salam (PS) group SU(4) × SU(2)L × SU(2)R, and trinification grand unified theory models of three fermion generations based on the group SU(3)C × SU(3)L × SU(3)R. We proceed with a brief review of a unification program of 4D gravity and SU(3) × SU(2) × U(1) Yang–Mills emerging from 8D pure quaternionic gravity. A realization of E8 in terms of the Cl(16) = Cl(8) ⊗ Cl(8) generators follows, as a preamble to F. Smith’s E8 and Cl(16) = Cl(8) ⊗ Cl(8) unification model in 8D. The study of chiral fermions and instanton backgrounds in CP2 and CP3 related to the problem of obtaining three fermion generations is thoroughly studied. We continue with the evaluation of the coupling constants and particle masses based on the geometry of bounded complex homogeneous domains and geometric probability theory. An analysis of neutrino masses, Cabbibo–Kobayashi–Maskawa quark-mixing matrix parameters, and neutrino-mixing matrix parameters follows. We finalize with some concluding remarks about other proposals for the unification of gravity and the Standard Model, like string, M, and F theories and noncommutative and nonassociative geometry.

scholarly journals Unitarity of neutrino mixing matrix

2019 ◽  
Vol 206 ◽  
pp. 09009
Author(s):  
Ha Nguyen Thi Kim ◽  
Van Nguyen Thi Hong ◽  
Son Cao Van
Keyword(s):  
Cp Violation ◽  
Neutrino Oscillations ◽  
Graphical Form ◽  
Muon Neutrinos ◽  
Neutrino Mixing ◽  
Electron Neutrinos ◽  
Tau Neutrinos ◽  
The Matrix ◽  
Mixing Matrix ◽  
Unitary Triangle

Neutrinos are neutral leptons and there exist three types of neutrinos (electron neutrinos νe, muon neutrinos νµ and tau neutrinos ντ). These classifications are referred to as neutrinos’s “flavors”. Oscillations between the different flavors are known as neutrino oscillations, which occurs when neutrinos have mass and non-zero mixing. Neutrino mixing is governed by the PMNS mixing matrix. The PMNS mixing matrix is constructed as the product of three independent rotations. With that, we can describe the numerical parameters of the matrix in a graphical form called the unitary triangle, giving rise to CP violation. We can calculate the four parameters of the mixing matrix to draw the unitary triangle. The area of the triangle is a measure of the amount of CP violation.

THREE-NEUTRINO OSCILLATIONS IN MATTER, CP-VIOLATION AND TOPOLOGICAL PHASES

1992 ◽  
Vol 01 (02) ◽  
pp. 379-399 ◽  
Author(s):  
V.A. NAUMOV
Keyword(s):  
Evolution Operator ◽  
Adiabatic Approximation ◽  
Neutrino Oscillations ◽  
Topological Phases ◽  
Matrix Elements ◽  
Neutrino Mixing ◽  
Time Evolution Operator ◽  
Adiabatic Approach ◽  
Flavor Mixing ◽  
Mixing Matrix

The phenomenon of Dirac neutrino oscillations in medium of varying density and composition is studied for the case of three lepton generations using the Berry adiabatic approach. The expressions for the topological phases γN are derived. It is shown that the Berry phases, arising when matter parameters vary periodically, are equal to zero identically, while in the case of noncyclic evolution, γN≢0 (in a special gauge) under the condition that all matrix elements of the flavor-mixing matrix in vacuum, CP-violating (Dirac) phase and neutrino-mass-squares differences are not equal to zero simultaneously. Exact formulas for the neutrino-mixing matrix in matter and adiabatic time-evolution operator are obtained. The recursion algorithm for the calculation of corrections to the adiabatic approximation is given

scholarly journals NEW CHANCE FOR RESEARCHES ON LORENTZ VIOLATION

2012 ◽  
Vol 10 ◽  
pp. 195-206 ◽  
Author(s):  
BO-QIANG MA
Keyword(s):  
Field Theory ◽  
Standard Model ◽  
Effective Field Theory ◽  
Lorentz Violation ◽  
Phenomenological Analysis ◽  
Effective Field ◽  
Standard Model Extension ◽  
Model Extension ◽  
The Standard Model

I present a brief review on the motivation for the study on Lorentz violation and on some of our studies with phenomenological analysis of Lorentz violation effects. I also discuss three effective field theory frameworks for Lorentz violation: the Coleman-Glashow model, the standard model extension (SME), and the standard model supplement (SMS). The situation of the OPERA "anomaly" is also briefly reviewed, together with some discussion on the superluminality of neutrinos within the effective field theory frameworks.

scholarly journals LORENTZ VIOLATION IN THREE-FAMILY NEUTRINO OSCILLATION

2009 ◽  
Vol 24 (31) ◽  
pp. 5861-5876 ◽  
Author(s):  
SHIMIN YANG ◽  
BO-QIANG MA
Keyword(s):  
Experimental Data ◽  
Neutrino Oscillation ◽  
Oscillation Amplitude ◽  
Lorentz Violation ◽  
Upper Bounds ◽  
Neutrino Energy ◽  
Neutrino Sector ◽  
Massless Neutrino ◽  
Neutrino Experiments ◽  
Mixing States

We analyze the consequences of Lorentz violation (LV) to three-generation neutrino oscillation in the massless neutrino sector. We present a general formalism of three-family neutrino oscillation with neutrino flavor states being mixing states of energy eigenstates. It is also found that the mixing parts could strongly depend on neutrino energy by special choices of LV parameters. By confronting with the existing experimental data on neutrino oscillation, the upper bounds on LV parameters are derived. Because the oscillation amplitude could vary with the neutrino energy, neutrino experiments with energy dependence may test and constrain the LV scenario for neutrino oscillation.

scholarly journals Probing the nonunitarity of the leptonic mixing matrix at the CEPC

2016 ◽  
Vol 31 (33) ◽  
pp. 1644006 ◽  
Author(s):  
Stefan Antusch ◽  
Oliver Fischer
Keyword(s):  
Field Theory ◽  
Standard Model ◽  
Effective Field Theory ◽  
New Physics ◽  
Effective Field ◽  
Neutrino Masses ◽  
Performance Parameters ◽  
The Standard Model ◽  
Mixing Matrix ◽  
Theory Framework

The nonunitarity of the leptonic mixing matrix is a generic signal of new physics aiming at the generation of the observed neutrino masses. We discuss the Minimal Unitarity Violation (MUV) scheme, an effective field theory framework which represents the class of extensions of the Standard Model (SM) by heavy neutral leptons, and discuss the present bounds on the nonunitarity parameters as well as estimates for the sensitivity of the CEPC, based on the performance parameters from the preCDR.

scholarly journals A systematic analysis of perturbations for hexagonal mixing matrix

2019 ◽  
Vol 34 (01) ◽  
pp. 1950005
Author(s):  
Sumit K. Garg
Keyword(s):  
Neutrino Mixing ◽  
Inverted Hierarchy ◽  
Systematic Analysis ◽  
Mixing Angle ◽  
Mixing Angles ◽  
Angle Data ◽  
Mixing Matrix ◽  
Global Fit ◽  
Pmns Matrix ◽  
The Impact

We present a systematic analysis of perturbative Hexagonal (HG) mixing for describing recent global fit neutrino mixing data with normal and inverted hierarchy. The corrections to unperturbed mixing are parametrized in terms of small orthogonal rotations [Formula: see text] with modified PMNS matrix of the forms [Formula: see text]. Here, [Formula: see text] is rotation in [Formula: see text] sector and [Formula: see text] is unperturbed Hexagonal mixing matrix. The detailed numerical investigation of all possible cases is performed with scanning of parameter space using [Formula: see text] approach. We found that the perturbative schemes governed by single rotation are unable to fit the mixing angle data even at [Formula: see text] level. The mixing schemes which involve two rotation matrices only [Formula: see text] are successful in fitting all neutrino mixing angles within [Formula: see text] range for normal hierarchy (NH). However for inverted hierarchy (IH), only [Formula: see text] is most preferable as it can fit all mixing angles at [Formula: see text] level. The remaining perturbative cases are either excluded at [Formula: see text] level or successful in producing mixing angles only at [Formula: see text] level. To study the impact of phase parameter, we also looked into CP violating effects for single rotation case. The predicted value of [Formula: see text] lies in the range [Formula: see text] for [Formula: see text] and [Formula: see text] case with normal (inverted) hierarchy.

scholarly journals CAN THE SUPER-KAMIOKANDE ATMOSPHERIC DATA PREDICT THE SOLAR NEUTRINO DEFICIT?

1999 ◽  
Vol 14 (10n11) ◽  
pp. 689-700 ◽  
Author(s):  
ION STANCU
Keyword(s):  
Solar Neutrino ◽  
Neutrino Oscillations ◽  
Atmospheric Neutrino ◽  
Neutrino Flux ◽  
Experimental Results ◽  
Neutrino Mixing ◽  
Mixing Angles ◽  
Atmospheric Data ◽  
Mixing Matrix ◽  
Good Agreement

In this letter we show that the evidence for neutrino oscillations from the super-Kamiokande atmospheric neutrino data fully determines the 3×3 neutrino-oscillations mixing matrix and predicts an energy-independent solar neutrino deficit at the level of 45%. This corresponds to a ratio of measured to predicted neutrino flux of [Formula: see text], in good agreement with the experimental results. We achieve this result within the framework of a minimal, three-generation neutrino mixing, with mass squared differences of ΔM2≃0.45 eV 2 and [Formula: see text]. The mixing matrix derived here is characterized by the mixing angles θ=35.1°, β=5.5° and ψ=23.3°, and a vanishing CP-violating phase, δ=0.

scholarly journals Standard Model EFTs via on-shell methods

2021 ◽  
Vol 2021 (11) ◽  
Author(s):  
Manuel Accettulli Huber ◽  
Stefano De Angelis
Keyword(s):  
Standard Model ◽  
Building Blocks ◽  
Effective Field ◽  
Tree Level ◽  
Matrix Elements ◽  
Effective Interactions ◽  
S Matrix ◽  
The Standard Model ◽  
Mass Dimension ◽  
Mixing Matrix

Abstract We present the Standard Model Effective Field Theories (SMEFT) from purely on-shell arguments. Starting from few basics assumptions such as Poincaré invariance and locality, we classify all the renormalisable and non-renormalisable interactions at lowest order in the couplings. From these building blocks, we review how locality and unitarity enforce Lie algebra structures to appear in the S-matrix elements together with relations among couplings (and hypercharges). Furthermore, we give a fully on-shell algorithm to compute any higher-point tree-level amplitude (or form factor) in generic EFTs, bypassing BCFW-like recursion relations which are known to be problematic when non-renormalisable interactions are involved. Finally, using known amplitudes techniques we compute the mixing matrix of SMEFT marginal interactions up to mass dimension 8, to linear order in the effective interactions.

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