arXiv subjects
Publications and source records attributed to Pralay Chakraborty.
A predictive neutrino mass matrix texture, sheltering unique correlations ($m_{12}=m_{13}\,\,\&\,\,m_{33}=2i\, m_{12}$), is proposed, addressing most of the timely neutrino phenomenology issues. The texture is realized in the framework of type-I + type-II seesaw in the light of the $A_4 \times Z_{10} \times Z_{7} \times Z_{3}$ group. The stability of the proposed texture is studied under renormalization group evolution.
A unified framework sheltering the type-I Dirac seesaw, based on the $Δ(27)$ group supplemented by other cyclic symmetries is proposed, preserving the naturalness of Yukawa couplings. It helps to visualize mass matrices within the lepton and quark sectors in terms of \textit{three universal parameters}: $Σ_1$, $Σ_2$, and $Σ_3$, highlighting that the down-type quark and light neutrino mass matrices exhibit a \textit{Hermitian} texture. Several phenomenological aspects, such as lepton flavour violation and nonunitarity of the lepton mixing matrix are explored. The stability of the proposed texture under renormalization group evolution is also investigated.
A novel symmetry for the neutrino mass matrix is proposed that naturally accommodates an inverted mass hierarchy while offering additional phenomenological advantages. The corresponding texture can be realized within a minimal framework based on $Δ(27)$ symmetry.
A minimal and predictive neutrino mass matrix texture for Majorana neutrino is proposed. The texture favours the normal hierarchy of neutrino mass eigenvalues. It further predicts the octant of $θ_{23}$, constraints $δ$, gives bounds on neutrino mass eigenvalues and also gives ranges for the two Majorana phases.The texture is realised in the framework of a Type-I seesaw and a Weinberg like dimension 6 operator under an extended symmetry of $SU(2)_L \otimes U(1)_Y \otimes A_4 \otimes Z_{10} \otimes Z_7 \otimes Z_5 \otimes Z_3$. The texture can be realised with different sets of vacuum expectation values of the associated scalar fields, but not all such sets lead to a viable scalar sector. The model also constrains the allowed channels of charged lepton flavour violation and leads to a suppressed baryon asymmetry generation through conventional leptogenesis.
We propose a new, minimal Majorana neutrino mass matrix texture and study its predictions within a partial tri-bimaximal (TBM) mixing scheme, where $\sinθ_{12} = 1/\sqrt{3}$ and $\sinθ_{23} = 1/\sqrt{2}$, with $θ_{13}$ and $δ$ treated as free parameters. The texture forbids $θ_{13} = 0$ and does not correspond to a $μ-τ$ symmetric structure. As a notable feature, the texture predicts the equality of the Majorana phases. In addition, we find that the predictions show distinct behavior depending on the sign of a single real texture parameter. The texture is realized through a hybrid framework of one Type-I seesaw and two Type-II seesaw mechanisms under an extended symmetry group, $SU(2)_L \otimes U(1)_Y \otimes A_4 \otimes Z_{10} \otimes Z_{7}$ with properly chosen model parameters. The texture is seen to favor the normal hierarchy for neutrino masses.
We plan to decipher the common origin of neutrino mass textures within a $Δ(27)$ based framework, in association with Type-I+II seesaw mechanism. Motivated by the diversity of texture structures used in phenomenological analyses, we examine how a single framework can reproduce them without additional assumptions. We show that the interplay between vacuum alignments, model parameters, and specific Yukawa choices naturally yields several well established neutrino mass textures in the literature. Our goal is to demonstrate that a minimal $Δ(27)$ framework can unify these viable textures within a common theoretical origin.
Under the exponential parametrization scheme $ m^ν_{ij}\sim r e^{i θ}$, we propose a \emph{unique} neutrino mass matrix texture that exhibits four correlations among its elements. The mixing scheme obtained from the proposed texture is consistent with experimental observations. We construct a concrete model based on the $SU(2)_L \times U(1)_Y \times A_4 \times Z_{10} \times Z_7$ group within the framework of the seesaw mechanism.
We propose two new predictive neutrino mass matrix textures that deviate from $μ$-$τ$ symmetry and explore their phenomenological implications. These textures are significant due to their predictive nature and the unique approach they introduce for breaking the $μ$-$τ$ symmetry. Both textures predict six physical parameters and impose sharp constraints on $θ_{23}$ and $δ$, considering both normal and inverted neutrino mass orderings. In addition, we realize the textures in their exact form within the framework of the seesaw mechanism, based on the $SU(2)_L \times A_4 \times Z_3$ symmetry group.
We propose a neutrino mass matrix texture bearing a suitable correlation $m_{22}=-2\,m_{13}$ and study its phenomenological implications. In light of both normal and inverted hierarchies, the texture imposes specific bounds on some observational parameters. As a potential application, the prediction of effective Majorana neutrino mass $m_{ββ}$ is visualized for both hierarchies. To understand the proposed texture from the first principle, we incorporate the type-I+II seesaw mechanism in association with $A_4 \times Z_{10} \times Z_2$ group.
We propose an elegant neutrino mass matrix texture entitled $μ$-$τ$ mixed symmetry highlighting two simple correlations among its elements and a detailed analysis is carried out to see its phenomenological implications. The proposed texture is motivated in the framework of Seesaw mechanism in association with $A_4$ symmetry
We endeavor to constrain the neutrino mass matrix on the phenomenological ground and procure model-independent textures by emphasizing on the simple linear relationships among the mass matrix elements. These simple textures predict the two Majorana phases. In this regard, two types of parametrization of neutrino mass matrix: general and exponential are employed. We obtain fifty-three predictive neutrino mass matrix textures, out of which twenty-eight are associated with the general parametrization, and the rest belong to the exponential one. Apart from Type-A/P textures, the rest deal with the prediction of a few other oscillation parameters as well. We try to realize the proposed textures in the light of $A_4$, $Δ\,(27)$ and $T_7$ symmetry groups.
A thought experiment is designed to speculate on the neutrino being trapped in an impenetrable potential well. Considering both relativistic and non-relativistic scenarios, we delve into several interesting facets connected to the flavour oscillation.
Two new neutrino mass matrix textures exhibiting the \emph{mixed $μ$-$τ$ symmetry} are proposed. The mass matrices hint for a promising neutrino mixing schemes and find their connections with $Δ(27)$ and $A_{4}$ discrete symmetry groups respectively.