Related papers: A framework for testing leptonic unitarity by neut…
We present a comprehensive study of the three-active plus $N$ sterile neutrino model as a framework for constraining leptonic unitarity violation induced at energy scales much lower than the electroweak scale. We formulate a perturbation…
In the presence of extra neutrino states at high scales, the low-energy effective $3\times 3$ leptonic mixing matrix (LMM) is in general nonunitary. We revisit the question of what is our current knowledge of individual LMM matrix elements…
The unitarity of the lepton mixing matrix is a critical assumption underlying the standard neutrino-mixing paradigm. However, many models seeking to explain the as-yet-unknown origin of neutrino masses predict deviations from unitarity in…
New heavy neutral leptons lead to non-unitary effects in models for neutrino masses. Such effects could represent a sign of new physics beyond the Standard Model, leading to observable deviations in neutrino oscillation experiments, lepton…
Unitarity is a fundamental property of any theory required to ensure we work in a theoretically consistent framework. In comparison with the quark sector, experimental tests of unitarity for the 3x3 neutrino mixing matrix are considerably…
A low energy non-unitary leptonic mixing matrix is a generic feature of many extensions of the Standard Model. In such a case, the task of future precision neutrino oscillation experiments is more ambitious than measuring the three mixing…
We present results of a combined analysis in neutrino oscillations without unitarity assumption in the $3\nu$ mixing picture. Constraints on neutrino mixing matrix elements are based on recent data from the reactor, solar and long-baseline…
We study the method to test the unitarity of the lepton mixing matrix by using only the long baseline neutrino oscillation experiments, such as the combination of the T2HK experiment and the one with the $\nu_e$ beam from a future neutrino…
The non-unitarity of the effective leptonic mixing matrix at low energies is a generic signal of extensions of the Standard Model (SM) with extra fermionic singlet particles, i.e. sterile or right-handed neutrinos, to account for the…
We determine the elements of the leptonic mixing matrix, without assuming unitarity, combining data from neutrino oscillation experiments and weak decays. To that end, we first develop a formalism for studying neutrino oscillations in…
A generalized phenomenological (3 + 2 + 1)-model with three active and three sterile neutrinos is considered for the calculation of the neutrino oscillation characteristics at normal mass hierarchy of active neutrinos and significant…
Anomalies in several short-baseline neutrino oscillation experiments suggest the possible existence of sterile neutrinos at about eV scale having appreciable mixing with the already known three neutrinos. We find that if such a light…
Nonunitarity can arise in neutrino oscillation when the matrix with elements $\mathbf{U}_{\alpha i}$ which relate the neutrino flavor $\alpha$ and mass $i$ eigenstates is not unitary when sum over the kinematically accessible mass…
Several anomalies observed in short-baseline neutrino experiments indicate that the standard 3-flavor framework may be incomplete and point towards the existence of light sterile neutrinos. Here, we present a concise review of the status of…
Deviations from unitarity of the CKM matrix in the quark sector are considered excellent windows to probe physics beyond the Standard Model. In its leptonic counterpart, the PMNS matrix, these searches are particularly motivated, as the new…
Neutrino flavour oscillation is one of the primary indication of the existence of new physics beyond standard model. The presence of small neutrino mass is indispensable to explicate the oscillation among different flavours of neutrino. By…
The three-flavor framework of neutrino oscillations successfully explains most experimental results, but persistent anomalies at short- and long-baseline experiments hint at the existence of additional light sterile states. In particular,…
Neutrino oscillations are well established and the relevant parameters determined with good precision, except for the CP phase, in terms of a unitary lepton mixing matrix. Seesaw extensions of the Standard Model predict unitarity deviations…
We uncover an interesting phenomenon that neutrino flavor transformation in slowly varying matter density imitates almost exactly that of vacuum neutrino oscillation under suitably chosen experimental parameters. It allows us to have…
The possible existence of light and heavy sterile neutrinos may give rise to direct and indirect unitarity violation of the $3\times3$ lepton mixing matrix respectively. In the current work we study the potential of future accelerator…