Related papers: Determining the heavy seesaw neutrino mass matrix …
We discuss symmetries and scenarios leading to quasi-degenerate neutrinos in type-I seesaw models. The existence of degeneracy in the present approach is not linked to any specific structure for the Dirac neutrino Yukawa coupling matrix…
We adopt a bottom-up approach to reconstruct the possible neutrino mass matrix patterns, in the hypothesis that $\lambda = \sin \theta_C$, where $\theta_C$ is the Cabibbo angle, is a useful expansion parameter in the neutrino sector as it…
The type I seesaw mechanism is one of the leading proposed explanations for how neutrinos acquire their tiny masses. However, the mass scale of the undiscovered right-handed neutrinos required by this mechanism remains undetermined.…
A novel scenario is presented within the Type-I seesaw mechanism in which no other beyond Standard Model fields except three heavy right handed neutrinos, have been considered. Light neutrino masses around sub eV scale, could be possible at…
In the seesaw model with hierarchical Dirac masses, the neutrino mixing angle exhibits the behavior of a narrow resonance. In general, the angle is strongly suppressed, but it can be maximal for special parameter values. We delineate the…
Recent research has indicated that the Standard Model (SM), while historically highly effective, is found to be insufficient due to its prediction of zero mass for neutrinos. With the exception of a few, the majority of the parameters…
Seesaw models with a small lepton number breaking can naturally accommodate electroweak-scale pseudo-Dirac neutrinos with a sizable mixing with the active neutrinos, while satisfying the light neutrino oscillation data. Due to the smallness…
Using the family symmetry, in the neutrino mass matrix we remove the Yukawa coupling (arising in the Dirac type mass between the heavy neutrinos and light lepton doublets) dependence in the double seesaw mechanism so that it is directly…
We study natural lepton mass matrices, obtained assuming the stability of physical flavour observables with respect to the variations of individual matrix elements. We identify all four possible stable neutrino textures from algebraic…
We discuss the implications for lepton mixing and CP violation of structure in the lepton mass matrices, for the case that neutrino masses are generated by the see-saw mechanism with an hierarchical structure for the Majorana masses. For a…
In this paper, we perform chiral perturbative analysis of an approximate lepton number symmetry associated with a sufficiently light neutrino in the type-I seesaw mechanism. For the Dirac mass matrix $m_{D} = (\bm A \, , \bm B \, , \bm C)$,…
We discuss the minimal seesaw model for the Dirac CP violating phase of the lepton mixing matrix. We introduce two right-handed Majorana neutrinos and obtain several textures of the tri-maximal lepton mixing matrices. Moreover, we discuss…
The measured values for the mixture angles in neutrino oscillations suggest the existence of a symmetry of interchange of flavor between muon and tau neutrinos. Using this symmetry we analyzed the minimal seesaw model for neutrino masses,…
We consider the see-saw mechanism within a non-supersymmetric SO(10) model. By assuming the SO(10) quark-lepton symmetry, and after imposing suitable conditions that ensure that the right-handed (RH) neutrino masses are at most mildly…
In the light of the recent measurement of the leptonic mixing angle $\theta_{13}$, implications of the latest mixing data have been investigated for non-minimal textures of lepton mass matrices pertaining to Dirac neutrinos. All these…
In this paper we investigate how well the nature of heavy neutral leptons can be determined at a future lepton collider, after its potential discovery. Considered in a simplified model are prompt decays of the neutrino in the mass range…
In a recent paper, we pointed out that mixing of the light neutrinos with heavy gauge singlet states could reconcile the Z-pole data from e+e- colliders and the nu_mu (anti-nu_mu) scattering data from the NuTeV experiment at Fermilab. We…
We reconsider an universal mass matrix model which has a seesaw-invariant structure with four-zero texture common to all quarks and leptons. The CKM quark and MNS lepton mixing matrices of the model are analyzed analytically.We show that…
A previous short analysis of the seesaw mechanism, based on quark-lepton symmetry, experimental data and hierarchical neutrino spectrum, is enlarged to include small but not zero U_{e3}, inverted mass hierarchy, and the qualitative effect…
Within the framework of a local SU(3) family symmetry model, we report a general analysis of the mechanism for neutrino mass generation and mixing, including light sterile neutrinos. In this scenario, ordinary heavy fermions, top and bottom…