CP Violation in SU(3) × U(1) Electroweak Model

1997 ◽  
Vol 12 (24) ◽  
pp. 4411-4424 ◽  
Author(s):  
Tae Hoon Lee ◽  
Dae Sung Hwang
Keyword(s):  
Cp Violation ◽  
Mass Matrix ◽  
Neutral Current ◽  
Tree Level ◽  
Additional Contribution ◽  
Matrix Elements ◽  
Mixing Angle ◽  
Mixing Matrix ◽  
Electroweak Model ◽  
New Phase

We study the charged and the neutral current interactions of quarks in an SU (3)L × U (1)X electroweak model. Based on the assumption that u-type quarks coincide with their mass eigenstates, we obtain a new mixing angle θ′ and another CP violating phase δ′ in the extra heavy quark sector besides the usual Kobayashi–Maskawa mixing matrix. This new phase δ′ does not effect a change in the mass matrix elements of the [Formula: see text] systems when θ′ is small, but extra heavy quarks and gauge bosons give rise to additional contribution to the real part of the off-diagonal mass matrix elements and then the CP violation parameter ε is modified. By requiring that the tree level FCNC does not have an important effect on the [Formula: see text] and [Formula: see text] mixings in this model, we obtain a new lower bound on the mass of the extra heavy neutral gauge boson as 1.8 TeV.

scholarly journals EXPERIMENTAL NEUTRINO PHYSICS

2005 ◽  
Vol 20 (14) ◽  
pp. 2895-2906
Author(s):  
K. Zuber
Keyword(s):  
Neutrino Physics ◽  
Cp Violation ◽  
Rest Mass ◽  
Double Beta Decay ◽  
Matrix Elements ◽  
Mass Measurements ◽  
Mixing Angle ◽  
Cosmological Observations ◽  
Absolute Mass ◽  
Mixing Matrix

The current experimental status of neutrino physics is reviewed. It contains the evidences for a non-vanishing neutrino rest mass from neutrino oscillation searches. In addition an outlook is given on determining the various mixing matrix elements and mass differences more precisely with new experiments. Of special interest is the value of the mixing angle θ13 determining the possibility of detecting leptonic CP violation in the future. The prospect for absolute mass measurements using beta and double beta decay as well as cosmological observations is presented.

scholarly journals A discrete anatomy of the neutrino mass matrix

2014 ◽  
Vol 29 (33) ◽  
pp. 1450179
Author(s):  
G. K. Leontaris ◽  
N. D. Vlachos
Keyword(s):  
Finite Group ◽  
Neutrino Mass ◽  
Mass Matrix ◽  
Current Data ◽  
Neutrino Mass Matrix ◽  
Linear Combinations ◽  
Mixing Angle ◽  
Mass Matrices ◽  
Mixing Matrix ◽  
Charged Leptons

We investigate the possibility of expressing the charged leptons and neutrino mass matrices as linear combinations of elements of a single finite group. Constraints imposed on the resulting mixing matrix by current data restrict the group types, but allow a nonzero value for the θ13 mixing angle.

scholarly journals AN ANALYTICAL TREATMENT OF THE NEUTRINO MASSES AND MIXINGS

2013 ◽  
Vol 28 (39) ◽  
pp. 1350184
Author(s):  
RENATA JORA ◽  
JOSEPH SCHECHTER ◽  
M. NAEEM SHAHID
Keyword(s):  
Cp Violation ◽  
Charged Lepton ◽  
Mass Matrix ◽  
Neutrino Masses ◽  
Analytical Treatment ◽  
Unit Matrix ◽  
Mixing Matrix ◽  
Analytical Formulas ◽  
Neutrino Masses And Mixings

We obtain analytical formulas which connect the neutrino masses and the leptonic mixing matrix with the entries in the mass matrix for the approximation in which the charged lepton mixing matrix is the unit matrix. We also extract the CP violation phase and determine the conditions in which this is present.

scholarly journals Lepton mass and mixing in a neutrino mass model based onS4flavor symmetry

2016 ◽  
Vol 31 (09) ◽  
pp. 1650039 ◽  
Author(s):  
V. V. Vien
Keyword(s):  
Cp Violation ◽  
Neutrino Mass ◽  
Tree Level ◽  
Neutrino Mixing ◽  
Mass Model ◽  
Mixing Angles ◽  
Neutrino Sector ◽  
Neutrino Mass And Mixing ◽  
Model Based ◽  
Mixing Matrix

We study a neutrino mass model based on [Formula: see text] flavor symmetry which accommodates lepton mass, mixing with nonzero [Formula: see text] and CP violation phase. The spontaneous symmetry breaking in the model is imposed to obtain the realistic neutrino mass and mixing pattern at the tree-level with renormalizable interactions. Indeed, the neutrinos get small masses from one [Formula: see text] doublet and two [Formula: see text] singlets in which one being in [Formula: see text] and the two others in [Formula: see text] under [Formula: see text] with both the breakings [Formula: see text] and [Formula: see text] are taken place in charged lepton sector and [Formula: see text] in neutrino sector. The model also gives a remarkable prediction of Dirac CP violation [Formula: see text] or [Formula: see text] in both the normal and inverted spectrum which is still missing in the neutrino mixing matrix. The relation between lepton mixing angles is also represented.

scholarly journals QUARK MASS HIERARCHY AND CP VIOLATION IN LOW ENERGY SUPERSYMMETRY

1996 ◽  
Vol 11 (23) ◽  
pp. 4307-4319 ◽  
Author(s):  
CHUN LIU
Keyword(s):  
Cp Violation ◽  
Quark Mass ◽  
Neutral Current ◽  
Vacuum Expectation ◽  
Discrete Symmetry ◽  
Low Energy ◽  
Tree Level ◽  
Mass Hierarchy ◽  
Family Symmetry ◽  
Flavor Changing

A pattern of quark mass hierarchy and CP violation within the framework of low energy supersymmetry is described. By assuming some discrete symmetry among the three families, the quarks of the third family obtain masses at tree level. The second family obtains masses radiatively at one-loop level due to the soft breaking of the family symmetry. At this level, the first family remains massless by some degeneracy conditions of the squarks. As a result of R parity violation, the sneutrino vacuum expectation values are nonvanishing. CP violation occurs through the superweak sneutrino exchange. This picture is consistent with the experiments on the flavor-changing neutral current.

scholarly journals CP violation, an experimental perspective

2005 ◽  
Vol 20 (14) ◽  
pp. 2975-2990 ◽  
Author(s):  
OWEN LONG
Keyword(s):  
Cp Violation ◽  
Electric Dipole ◽  
Dipole Moments ◽  
Low Energy ◽  
High Mass ◽  
Experimental Investigations ◽  
Matrix Elements ◽  
Electric Dipole Moments ◽  
Mixing Matrix ◽  
Near Future

I present a review of current and near-future experimental investigations of CP violation. In this review, I cover limits on particle electric dipole moments (EDMs) and CP violation studies in the K and B systems. The wealth of results from the new B factories provide impressive constraints on the CKM quark mixing matrix elements. Current and future measurements are focusing on processes dominated by loop diagrams, which probe physics at high mass scales in low-energy experiments.

scholarly journals ISOSPIN SYMMETRY BREAKING IN B → K*γ DECAY DUE TO AN EXTRA GENERATION OF VECTOR QUARKS

2005 ◽  
Vol 20 (27) ◽  
pp. 6229-6240 ◽  
Author(s):  
MOHAMMAD R. AHMADY ◽  
FARRUKH CHISHTIE
Keyword(s):  
Symmetry Breaking ◽  
Neutral Current ◽  
Tree Level ◽  
Additional Contribution ◽  
Isospin Symmetry ◽  
Flavor Changing ◽  
Flavor Changing Neutral Current ◽  
Acceptable Model ◽  
Isospin Symmetry Breaking ◽  
Zero Tree

The extra contributions due to an extra generation of vector-like quarks to the isospin symmetry breaking observable associated with the radiative B → K*γ decay is obtained. It is shown that this additional contribution is sensitive to the nonunitarity parameter Usb, which is a measure of the the strength of the non-zero tree-level flavor changing neutral current in this model. The significance of this result is that, once accurate experimental results on the isospin asymmetry becomes available, one can constrain the Usb independent of the mass of the extra quarks and so a much more stringent acceptable model parameter space could be obtained.

scholarly journals The impact of different parameterizations on the interpretation of CP violation in neutrino oscillations

2021 ◽  
Vol 2021 (5) ◽  
Author(s):  
Peter B. Denton ◽  
Rebekah Pestes
Keyword(s):  
Cp Violation ◽  
Mass Matrix ◽  
Current Data ◽  
Good Precision ◽  
Lepton Sector ◽  
Complex Phase ◽  
Dependent Variables ◽  
Mixing Matrix ◽  
Definition Of ◽  
The Impact

Abstract CP violation in the lepton mass matrix will be probed with good precision in upcoming experiments. The amount of CP violation present in oscillations can be quantified in numerous ways and is typically parameterized by the complex phase δPDG in the standard PDG definition of the lepton mixing matrix. There are additional parameterizations of the lepton mixing matrix as well. Through various examples, we explore how, given the current data, different parameterizations can lead to different conclusions when working with parameterization dependent variables, such as δ. We demonstrate how the smallness of |Ue3| governs the scale of these results. We then demonstrate how δ can be misleading and argue that the Jarlskog is the cleanest means of presenting the amount of CP violation in the lepton sector. We also confirm that, among the different parameterizations considered, the standard PDG parameterization has a number of convenient features.

scholarly journals (g − 2)μ versus K → π + Emiss induced by the (B − L)23 boson

2021 ◽  
Vol 2021 (4) ◽  
Author(s):  
Zhaofeng Kang ◽  
Yoshihiro Shigekami
Keyword(s):  
Cp Violation ◽  
Standard Model ◽  
Neutral Current ◽  
Tree Level ◽  
Meson Decays ◽  
Loop Level ◽  
Flavor Changing ◽  
The Standard Model ◽  
Flavor Changing Neutral Current

Abstract To address the long-standing (g − 2)μ anomaly via a light boson, in ref. [1] we proposed to extend the standard model (SM) by the local (B − L)23, under which only the second and third generations of fermions are charged. It predicts an invisible Z′ with mass $$ \mathcal{O}(100) $$ O 100 MeV, and moreover it has flavor-changing neutral current (FCNC) couplings to the up-type quarks at tree level. Such a Z′, via KL→ π0 + Z′(→$$ v\overline{v} $$ v v ¯ ) at loop level, may be a natural candidate to account for the recent KOTO anomaly. In this article, we investigate this possibility, to find that Z′ can readily do this job if it is no longer responsible for the (g − 2)μ anomaly. We further find that both anomalies can be explained with moderate tuning of the CP violation, but may contradict the B meson decays.

scholarly journals NEUTRINO MIXING AND THE DOUBLE TETRAHEDRAL GROUP

2013 ◽  
Vol 28 (29) ◽  
pp. 1350157 ◽  
Author(s):  
YONI BENTOV ◽  
A. ZEE
Keyword(s):  
Group Theory ◽  
Cp Violation ◽  
Neutrino Mass ◽  
Mass Matrix ◽  
Double Cover ◽  
Neutrino Mass Matrix ◽  
Two Dimensional ◽  
Neutrino Mixing ◽  
Mixing Matrix ◽  
Relevant Group

In the spirit of a previous study of the tetrahedral group T ≃A4, we discuss a minimalist scheme to derive the neutrino mixing matrix using the double tetrahedral group T′, the double cover of T. The new features are three distinct two-dimensional representations and complex Clebsch–Gordan coefficients, which can result in a geometric source of CP violation in the neutrino mass matrix. In an appendix, we derive explicitly the relevant group theory for the tetrahedral group T and its double cover T′.

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