Work

On the orthogonal matrix in the Casas-Ibarra parametrization for the Yukawa interactions of Majorana neutrinos

Year: 2024

Type: article

Abstract: The Casas-Ibarra (CI) parametrization of the Yukawa coupling matrix of Majorana neutrinos is generalized by considering the exact seesaw relation and including non-unitarity of the 3 × 3 Pontecorvo-Maki-Nakagawa-Sakata (PMNS) flavor mixing matrix. With the help of a full 6 × 6 Euler-like block description of the flavor structure for the seesaw mechanism, we find that the orthogonal matrix O in the CI parametrization can be expressed as O i j = M j / m i F i j with m i and M j being the masses of light and heavy Majorana neutrinos and F i j consisting of the PMNS and active-sterile flavor mixing parameters (for i , j = 1 , 2 , 3 ). Assuming a specific pattern of O is therefore equivalent to imposing some special conditions on the seesaw parameter space.

Source: Nuclear Physics B

DOI: 10.1016/j.nuclphysb.2024.116723

Author: Zhi-zhong Xing

Institutions: Peking University, Institute of High Energy Physics, University of Chinese Academy of Sciences

Language: English

Topic: Neutrino Physics Research

Subfield: Nuclear and High Energy Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: diamond

Funder: National Natural Science Foundation of China

Award: G4256929292