Investigating Two-zero Textures of Inverse Neutrino Mass Matrix under the Lamp Post of LMA and DLMA Solutions and Symmetry Realization

Abstract

In this paper, we study the phenomenological consequences of two-zero textures of inverse neutrino mass matrix(M −1 ν ). In M l and MD diagonal basis, zero(s) in heavy right-handed neutrino mass matrix correspond to zero(s) in inverse neutrino mass matrix(M −1 ν ). There are fifteen possibilities to have two-zero textures of M −1 ν . In order to study complete phenomenology of the model, we confront these textures with the latest neutrino data including large mixing angle(LMA) and dark -large mixing angle(DLMA) degenerate solutions, later of which originates if neutrinos exhibit non-standard interactions with matter. Out of fifteen possibilities only seven(B2, B4, C1, C3, D1, D2, E1) are found to be in consonance with LMA and/or DLMA solutions. In general, we find that the textures for which (M −1 ν )11 = 0 are disallowed. The textures B2, B4, C1, C3 and D2 textures are found to be allowed under both LMA and DLMA descriptions. Also, these textures are necessarily CP violating. However, the textures which are not consistent with DLMA paradigm, for example D1 and E1, allow both CP conserving and violating solutions. The generic feature of the class of model discussed in the present work is the existence of neutrino mass hierarchy degeneracy in a particular texture.For example, if a texture is allowed by LMA solution with "X" neutrino mass hierarchy then, if DLMA is allowed, it is allowed with the same hierarchy "X". Interestingly, amongst all the seven texture, textures with (M −1 ν )23 = 0 are found to be either disallowed or are consistent with LMA(D1 and E1) description only. We have, also, obtained the implication of the model for 0νββ decay amplitude |Mee|. Except for textures D1 and E1, the predicted 3σ lower bound on |Mee| is O(10 −2 ) which is within the sensitivity reach of 0νββ decay experiments like SuperNEMO, KamLAND-Zen, NEXT, and nEXO. For example, the non-observation of 0νββ decay down to these high sensitivities will refute all the textures except D1 and E1. Furthermore, we have proposed a flavor model, based on discrete non-Abelian flavor group A4, wherein such textures of M −1 ν can be realized within Type-I seesaw setting.

Gauged $U(1)_{L_μ-L_τ}$ Symmetry and two-zero Textures of Inverse Neutrino Mass Matrix in light of Muon ($g-2$)

“…which corresponds to D 1 texture of M −1 ν studied in Ref. [45]. Also, if the charge assignment of Φ 2 under U (1) Lµ−Lτ and Z 4 are replaced by −2 and 1, respectively, then we obtain, M R , given by…”

“…[42][43][44]. Recently, the authors have investigated all possible two-zero texture inverse neutrino mass matrices (M −1 ν ) in light of large mixing angle(LMA) and dark-large mixing angle(DLMA) solutions of neutrino mixing paradigm [45]. Out of fifteen possible two-zero M −1 ν textures only seven are found to be in consonance with current neutrino oscillation data.…”

“…The two-zero texture of M −1 ν obtained using Eqn. (15) corresponds to E 1 texture with zeroes at (2, 3) and (3, 3) place [45].…”

“…In the present work, we have realized two such textures D 1 and E 1 ( for notation of textures see Ref. [45]) accommodating muon (g − 2) anomaly and neutrino oscillation data, simultaneously. We have employed U (1) Lµ−Lτ symmetry extending the SM with three right-handed neutrinos and three scalar singlet fields.…”