Leptonic CP violation in a two parameter model

Abstract

We further study the "complementary" Ansatz, Tr$(M_{\nu })$=0, for a prediagonal light Majorana type neutrino mass matrix. Previously, this was studied for the CP conserving case and the case where the two Majorana type CP violating phases were present but the Dirac type CP violating phase was neglected. Here we employ a simple geometric algorithm which enables us to "solve" the Ansatz including all three CP violating phases. Specifically, given the known neutrino oscillation data and an assumed two parameter (the third neutrino mass $m_3$ and the Dirac CP phase $\delta$) family of inputs we predict the neutrino masses and Majorana CP phases. Despite the two parameter ambiguity, interesting statements emerge. There is a characteristic pattern of interconnected masses and CP phases. For large $m_3$ the three neutrinos are approximately degenerate. The only possibility for a mass hierarchy is to have $m_3$ smaller than the other two. A hierarchy with $m_3$ largest is not allowed. Small CP violation is possible only near two special values of $m_3$. Also, the neutrinoless double beta decay parameter is approximately bounded as 0.020 eV $<|m_{ee}|<$ 0.185 eV. As a byproduct of looking at physical amplitudes we discuss an alternative parameterization of the lepton mixing matrix which results in simpler formulas. The physical meaning of this parameterization is explained.

12 pages, 1 figure

References in corpus (1)

• Study of leptonic CP violation

Cited by in corpus (20)

• The Elements of the Neutrino Mass Matrix: Allowed Ranges and Implications of Texture Zeros
• μ-τSymmetry and Maximal CP Violation
• Flavor mixings and textures of the fermion mass matrices
• Texture 4 zero Fritzsch-like lepton mass matrices
• An approach to permutation symmetry for the electroweak theory
• Can four-zero-texture mass matrix model reproduce the observed quark and lepton mixing angles and CP violating phases?
• Perturbed S3 neutrinos
• A New Type of Complex Neutrino Mass Texture and mu-tau Symmetry
• Texture specific mass matrices with Dirac neutrinos and their implications
• Possible textures of the fermion mass matrices
• Determination of Neutrino Mass Texture for Maximal CP Violation
• Broken Flavor 2 <-> 3 Symmetry and phenomenological approach for universal quark and lepton mass matrices
• Exploring the parameter space of texture 4 zero quark mass matrices
• Doubly perturbed $S_3$ neutrinos and the $s_{13}$ mixing parameter
• Neutrino Mass Textures with Maximal CP Violation
• Investigating non-Fritzsch like texture specific quark mass matrices
• Modified Zee mass matrix with zero-sum condition
• Fine structure of beta decay endpoint spectrum
• Quark Mixing from Mass Matrix Model with Flavor 2 (\leftrightarrow) 3 Symmetry
• Investigating texture six zero lepton mass matrices