CPviolations in lepton number violation processes and neutrino oscillations

Abstract

We examine the constraints on the MNS lepton mixing matrix from the present and future experimental data of the neutrino oscillation and lepton number violation processes. We introduce a graphical representation of the CP violation phases which appear in the lepton number violation processes such as neutrinoless double beta decay, the µ − − e + conversion, and the K decay, K − → π + µ − µ − . Using this graphical representation, we derive the constraints on the CP violation phases in the lepton sector. PACS number(s): 14.60Pq, 11.30.Er, 23.40.Bw

Maki-Nakagawa-Sakata parameters from neutrino oscillations, single beta decay, and double beta decay

“…Let us review our graphical representations of the complex mass and the CP violating phases appeared in (ββ) 0ν , which are proposed in [9] [10]. The averaged mass m ν of Eq.…”

“…This triangle is referred to the complex-mass triangle [9] [10]. The three mixing matrix elements |U ej | 2 (j = 1, 2 and 3) indicate the division ratios for the three portions of each side of the triangle which are divided by the parallel lines to the side lines of the triangle passing through the M ee (Fig.2).…”

“…In these situations it is necessary to confine the MNS parameters and the Majorana phases by incorporating all these direct and indirect experiments. To disentangle the complicated correlations among the data from many different kinds of experiments, we proposed a graphical method [9] [10]. This method enables us to grasp the geometrical relations among the parameters of masses, mixing angles, CP phases etc.…”

Model Independent Constraints of the Averaged Neutrino Masses Revisited

“…In the present paper, by using these new developments we reexamine the constraints of the averaged neutrino masses from the MNS parameters together with the cosmological constraint (8). For the NH case in which m 1 < m 2 < m 3 , the neutrino masses are written in terms of m ν under the unitarity condition i |U ei | 2 = 1 as [10]…”

“…In the following numerical analysis, we take the center values of s 2 12 , s 2 13 , ∆m 2 31 , ∆m 2 21 given by ( 9), ( 12)-( 16), while we vary the values from 0 to 2π for Majorana CP violating phases β and γ and for the Dirac CP violating phase δ too. As for s 2 23 , we take the lower, center, and upper values shown in (10) and (11) for typical values for s 2 First, following our ealiar work [10], we derive the neumerical lower limit of m ν . In the NH case, the following lower limit of m ν is derived from (17) with m 2 1 ≥ 0,…”