Flavor mixing and 
CP
 violation from the interplay of an 
S4
 modular group and a generalized 
CP
 symmetry

Abstract In a class of neutrino mass models with modular flavor symmetries, it has been observed that CP symmetry is preserved at the fixed point (or stabilizer) of the modulus parameter τ = i, whereas significant CP violation emerges within the neighbourhood of this stabilizer. In this paper, we first construct a viable model with the modular $$ {A}_5^{\prime } $$ A 5 ′ symmetry, and explore the phenomenological implications for lepton masses and flavor mixing. Then, we introduce explicit perturbations to the stabilizer at τ = i, and present both numerical and analytical results to understand why a small deviation from the stabilizer leads to large CP violation. As low-energy observables are very sensitive to the perturbations to model parameters, we further demonstrate that the renormalization-group running effects play an important role in confronting theoretical predictions at the high-energy scale with experimental measurements at the low-energy scale.

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NEUTRINOS: LOOKING FORWARD TO THE FUTURE

International Journal of Modern Physics E ◽

10.1142/s0218301307006691 ◽

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.

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Implications of the Daya Bay observation of θ 13 on the leptonic flavor mixing structure and CP violation

Chinese Physics C ◽

10.1088/1674-1137/36/4/l01 ◽

2012 ◽

Vol 36 (4) ◽

pp. 281-297 ◽

Cited By ~ 42

Author(s):

Zhi-Zhong Xing

Keyword(s):

Cp Violation ◽

Daya Bay ◽

Flavor Mixing

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Lepton Mixing Patterns from PSL2(7) with a Generalized CP Symmetry

Advances in High Energy Physics ◽

10.1155/2020/6120803 ◽

2020 ◽

Vol 2020 ◽

pp. 1-13

Author(s):

Shu-Jun Rong

Keyword(s):

Effective Mass ◽

Beta Decay ◽

Charged Lepton ◽

Modular Group ◽

Neutrinoless Double Beta Decay ◽

Double Beta Decay ◽

Global Fit ◽

Mixing Patterns ◽

Cp Symmetry

Lepton mixing patterns from the modular group PSL2(7) with generalized CP symmetries are studied. The residual symmetries in both charged lepton and neutrino sectors are Z2×CP. Seven types of mixing patterns at the 3σ level of the new global fit data are obtained. Among these patterns, three types of patterns can give the Dirac CP phase which is in the 1σ range of the global fit data. The effective mass of neutrinoless double-beta decay for these patterns is also examined.

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CKM MATRIX ELEMENT MAGNITUDES

International Journal of Modern Physics A ◽

10.1142/s0217751x04018932 ◽

2004 ◽

Vol 19 (07) ◽

pp. 1004-1016 ◽

Cited By ~ 1

Author(s):

K. R. SCHUBERT

Keyword(s):

Matrix Element ◽

Cp Violation ◽

B Meson ◽

Matrix Elements ◽

Perfect Agreement ◽

B Meson Decays ◽

Ckm Matrix ◽

Cp Violations ◽

The Matrix ◽

Cp Symmetry

The present status of experimental results for the magnitudes of Cabibbo-Kobayashi-Maskawa matrix elements is reviewed and used for a unitarity test. The matrix is found to be unitary within ±1.8 standard deviations. The matrix violates CP-symmetry and the size of its CP-violation, as derived from only magnitude measurements and unitarity, is in perfect agreement with the observed CP-violations in K and B meson decays.

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Quark mass hierarchies, flavor mixing and maximal CP-violation

Broken Symmetries - Lecture Notes in Physics ◽

10.1007/bfb0105526 ◽

2008 ◽

pp. 131-149

Author(s):

Harald Fritzsch

Keyword(s):

Cp Violation ◽

Quark Mass ◽

Flavor Mixing

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Thank Heaven for Little Flaws

10.1093/oso/9780198814825.003.0001 ◽

2018 ◽

Author(s):

Steven E. Vigdor

Keyword(s):

Cp Violation ◽

Gravitational Collapse ◽

Charge Conjugation ◽

Symmetry Principles ◽

Perfect Symmetry ◽

Cp Symmetry

Chapter 1 introduces central themes of the book by dealing with the importance of symmetry principles in physics and of small symmetry violations (or “flaws”) in establishing conditions for life. It provides a visual analog of the combined symmetries of parity (P) and charge conjugation (C) via a drawing by M.C. Escher. Escher’s signature represents a small imperfection in the drawing’s otherwise nearly perfect symmetry, inspiring the book’s title. This chapter argues that a well-tuned violation of the combined CP symmetry (i.e., a CP violation) is necessary to establish a preference for matter over antimatter (i.e., matter–antimatter asymmetry), while still allowing for a long-lived universe that resists gravitational collapse. The chapter establishes the book’s focus on the intricate tapestry of inventive experiments physicists are pursuing to expose and quantify the extent of these tiny flaws.

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