Speaker
Description
The time evolution of lepton numbers of Majorana neutrinos are sensitive to neutrino masses , the mixing angles , and CP violation at low energy including Majorana phases and Dirac Kobayashi Maskawa type phase. This implies one can theoretically reconstruct all the elements of the effective Majorana mass matrix at low energy using the time evolution of lepton numbers. In this talk, we diagonalize the 2 × 2 effective Majorana matrix for two generations of the active Majorana neutrinos and express a Majorana phase, the two neutrinos masses, and a mixing angle in terms of the elements of the mass matrix. Then by assuming the origin of the effective Majorana mass matrix comes from type I seesaw model with two gauge singlet neutrinos, we have derived the relation of the single Majorana phase at low energy and two CP violating phases relevant for leptogenesis by drawing the triangles for the elements of the mass matrix in the complex plane which shows the contribution of each singlet neutrino to the elements of the effective Majorana mass matrix.
The talk is based on arXiv:2212.00142v4[hep-ph] 27 Dec 2024.
Nicholas J. Benoit, Yuta Kawamura, Saki Hamada, Takuya Morozumi, Yusuke Shimizu, Kei Yamamoto
