Weak-basis invariants and CP conservation in the leptonic sector with Majorana neutrinos

A comprehensive review of several aspects of fermion mixing phenomenon and texture specific mass matrices have been presented. Regarding fermion mixings, implications of unitarity and certain new developments for the CKM paradigm have been discussed. In the leptonic sector, the question of possibility of CP violation has been discussed in detail from the unitarity triangle perspective. In the case of texture specific mass matrices, the issues of viability of Fritzsch-like as well as non-Fritzsch-like mass matrices have been detailed for both the quark and leptonic sectors. The relationship of textures, naturalness and weak basis rotations has also been looked into. The issue of the compatibility of texture specific mass matrices with the SO(10)-based GUT mass matrices has also been discussed.

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Texture zero mass matrices and CP violation

International Journal of Modern Physics A ◽

10.1142/s0217751x17420052 ◽

2017 ◽

Vol 32 (16) ◽

pp. 1742005 ◽

Cited By ~ 2

Author(s):

Gulsheen Ahuja ◽

Samandeep Sharma

Keyword(s):

Cp Violation ◽

Viable Option ◽

Weak Basis ◽

Zero Mass ◽

Leptonic Sector ◽

Mass Matrices ◽

The Standard Model ◽

Texture Zero ◽

General Mass ◽

Invariant Parameter

Within the Standard Model, using the facility of making Weak Basis transformations, attempt has been made to examine the most general mass matrices within the texture zero approach. For the case of quarks, interestingly, one finds a particular set of texture four zero quark mass matrices emerging out to be a unique viable option for the description of quark mixing data as well as for accommodation of CP violation. Similarly, general lepton mass matrices, essentially considered as texture zero mass matrices, yield interesting bounds on the CP violating Jarlskog’s rephasing invariant parameter in the leptonic sector.

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Flavor invariants and renormalization-group equations in the leptonic sector with massive Majorana neutrinos

Journal of High Energy Physics ◽

10.1007/jhep09(2021)053 ◽

2021 ◽

Vol 2021 (9) ◽

Cited By ~ 1

Author(s):

Yilin Wang ◽

Bingrong Yu ◽

Shun Zhou

Keyword(s):

Renormalization Group ◽

Invariant Theory ◽

Hilbert Series ◽

Numerical Solutions ◽

System Of Differential Equations ◽

Generating Set ◽

Leptonic Sector ◽

Renormalization Group Equations ◽

Majorana Neutrinos ◽

Charged Leptons

Abstract In the present paper, we carry out a systematic study of the flavor invariants and their renormalization-group equations (RGEs) in the leptonic sector with three generations of charged leptons and massive Majorana neutrinos. First, following the approach of the Hilbert series from the invariant theory, we show that there are 34 basic flavor invariants in the generating set, among which 19 invariants are CP-even and the others are CP-odd. Any flavor invariants can be expressed as the polynomials of those 34 basic invariants in the generating set. Second, we explicitly construct all the basic invariants and derive their RGEs, which form a closed system of differential equations as they should. The numerical solutions to the RGEs of the basic flavor invariants have also been found. Furthermore, we demonstrate how to extract physical observables from the basic invariants. Our study is helpful for understanding the algebraic structure of flavor invariants in the leptonic sector, and also provides a novel way to explore leptonic flavor structures.

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CP properties of the leptonic sector for Majorana neutrinos

Nuclear Physics B ◽

10.1016/0550-3213(83)90393-0 ◽

1983 ◽

Vol 228 (1) ◽

pp. 21-30 ◽

Cited By ~ 57

Author(s):

J. Bernabéu ◽

P. Pascual

Keyword(s):

Leptonic Sector ◽

Majorana Neutrinos

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Weak basis transformations and texture zeros in the leptonic sector

Physics Letters B ◽

10.1016/j.physletb.2008.10.059 ◽

2009 ◽

Vol 670 (4-5) ◽

pp. 340-349 ◽

Cited By ~ 48

Author(s):

G.C. Branco ◽

D. Emmanuel-Costa ◽

R. González Felipe ◽

H. Serôdio

Keyword(s):

Weak Basis ◽

Leptonic Sector

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Complete leading-order standard model corrections to quantum leptogenesis

Journal of High Energy Physics ◽

10.1007/jhep09(2020)036 ◽

2020 ◽

Vol 2020 (9) ◽

Author(s):

Paul Frederik Depta ◽

Andreas Halsch ◽

Janine Hütig ◽

Sebastian Mendizabal ◽

Owe Philipsen

Keyword(s):

Standard Model ◽

Gauge Coupling ◽

Thermal Bath ◽

Leading Order ◽

Boltzmann Equations ◽

The Standard Model ◽

Majorana Neutrinos ◽

Infinite Loop ◽

First Time ◽

The Universe

Abstract Thermal leptogenesis, in the framework of the standard model with three additional heavy Majorana neutrinos, provides an attractive scenario to explain the observed baryon asymmetry in the universe. It is based on the out-of-equilibrium decay of Majorana neutrinos in a thermal bath of standard model particles, which in a fully quantum field theoretical formalism is obtained by solving Kadanoff-Baym equations. So far, the leading two-loop contributions from leptons and Higgs particles are included, but not yet gauge corrections. These enter at three-loop level but, in certain kinematical regimes, require a resummation to infinite loop order for a result to leading order in the gauge coupling. In this work, we apply such a resummation to the calculation of the lepton number density. The full result for the simplest “vanilla leptogenesis” scenario is by $$ \mathcal{O} $$ O (1) increased compared to that of quantum Boltzmann equations, and for the first time permits an estimate of all theoretical uncertainties. This step completes the quantum theory of leptogenesis and forms the basis for quantitative evaluations, as well as extensions to other scenarios.

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