相关论文: Unitarity Constraints on Neutrino Mass and Mixings

We explore the implications of imposing the constraint that two neutrino flavors (which for definiteness we take to be the mu and tau neutrinos) are similarly coupled to the mass basis in addition to the unitarity constraints. We allow…

Uncertainties in flavor and mass eigenstates of neutrinos are considered within the majorization approach. Nontrivial bounds reflect the fact that neutrinos cannot be simultaneously in flavor and mass eigenstates. As quantitative measures…

Certainly one of the most exciting areas of research at present is neutrino physics. The neutrinos are fantastically numerous in the universe and as such they have bearing on our understanding of the universe. Therefore, we must understand…

I review the main options one has of introducing mass to neutrinos, including broken R-parity models, as well as the constraints on neutrino properties that follow from astrophysics, cosmology as well as laboratory observations.

Observations of atmospheric neutrinos are usually analyzed using the simplifying approximation that either \(\nu_\mu \leftrightarrow \nu_\tau\) or \(\nu_e \leftrightarrow \nu_\mu\) two-flavor mixing is relevant. Here we instead consider the…

Whether the neutrino mass spectrum is normal (m_1 < m_2 < m_3) or abnormal (m_3 < m_1 < m_2) remains an open question, but we show that the latter possibility looks quite unnatural when it is related to the lepton flavor mixing matrix U in…

This essay is intended to provide a brief description of the peculiar properties of neutrinos within and beyond the standard theory of weak interactions. The focus is on the flavor oscillations of massive neutrinos, from which one has…

Status of determination of the neutrino masses and mixing is formulated and possible uncertainties, especially due to presence of the sterile neutrinos, are discussed. The data hint an existence of special ``neutrino'' symmetries. If not…

The theoretical basics of neutrino mass and mixing are reviewed. Dirac and Majorana masses are explained, and added together to produce the see-saw picture of the lightness of neutrinos. This picture predicts that neutrinos are Majorana…

Phenomenological implications of neutrino oscillations implied by recent experimental data on pattern of neutrino mass matrix are disscussed. It is shown that it is possible to have a neutrino mass matrix which shows approximate flavor…

We look at the possibility that appreciable neutrino masses and flavor mixing occur only within material media, driven by an interaction between leptons and a very light scalar particle. Limits are placed on the scalar particle mass and…

To realize the condition of sin^2(2theta_{12})>>sin^2(theta_{13}), we find constraints on flavor neutrino masses M_{ij} (ij=e,\mu,\tau): C1) c_{23}^2 M_{\mu\mu} + s_{23}^2 M_{\tau\tau} \approx 2 s_{23} c_{23}M_{\mu\tau} + M_{ee} and/or C2)…

We discuss the implications of large neutrino mixings for grand unified theories based on the seesaw mechanism. In SU(5) GUTs large mixings can be accomodated by means of $U(1)_F$ flavour symmetries. In these models the heavy Majorana…

It is hypotesized that neutrinos are massles and mixed among three (muon, electron and tau) flavors with a mixing length proportional to (E_nu/E_Planck)^-2. It is suggested that this hypothesis mostly reconciles the standard solar models…

In the recent years neutrino experiments have studied in detail the phenomenon of neutrino oscillations and most of the oscillation parameters have been measured with a good accuracy. However, in spite of many interesting ideas, the problem…

All the possible schemes of neutrino mixing with four massive neutrinos inspired by the existing experimental indications in favour of neutrino mixing are considered. It is shown that the scheme with a neutrino mass hierarchy is not…

I discuss neutrino mixing ansatze, such as the generalized Tri-bimaximal and bi-large mixing patterns, and their utility in describing the oscillation data. Unitarity tests and probes of the absolute neutrino mass scale are briefly…

Neutrino masses and mixing are generated in a supersymmetric standard model when R-parity is violated in bilinear mass terms. The mixing matrix among the neutrinos takes a restrictive form if the lepton flavor universality holds in the…

The recent IceCube observation of ultra-high-energy astrophysical neutrinos has begun the era of neutrino astronomy. In this work, using the unitarity of leptonic mixing matrix, we derive nontrivial unitarity constraints on the flavor…

The flavor composition of astrophysical neutrinos observed at neutrino telescopes is related to the initial composition at their sources via oscillation-averaged flavor transitions. If the time evolution of the neutrino flavor states is…