相关论文: Simple Model for (3+2) Neutrino Oscillations
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…
We propose a simple extension of the MSSM based on extra compact dimensions which includes an $SU(2) \otimes U(1)$ singlet superfield. The fermion present in this superfield is the sterile neutrino, which combines with one linear…
A simple renormalizable U(1) gauge model is constructed to explain the smallness of the active neutrino masses and provide the stable cold dark matter candidate simultaneously. The local U(1) symmetry is assumed to be spontaneously broken…
A number of short baseline neutrino oscillation experiments have observed an anomalous excess of neutrinos in the low energy range. This may hint towards the existence of additional neutrino mass splittings. If true, additional sterile…
The recent data describing the evidence for neutrino oscillations by Super Kamiokande implies that two neutrinos are very strongly mixed. We ask the question: can approximate maximal neutrino mixing be natural in unified (GUT or string)…
We studied models of leptogenesis where three right-handed Majorana neutrinos are involved and the minimal-extended seesaw mechanism including an additional singlet field produces four light neutrinos. This study shows that the type of mass…
If light sterile neutrinos are needed to understand the neutrino puzzles, as is currently indicated, a major theoretical challenge is to understand why its mass is so small. It is a more serious problem than understanding the small mass of…
Given the particle content of the standard model without and with a right-handed neutrino, the requirement that all anomalies cancel singles out a set of possible global symmetries which can be gauged. I review this topic and propose a new…
We describe an extention of the Standard Model (the $\nu$MSM) by three light singlet Majorana fermions -- sterile neutrinos, which allows to address simultaneously the problem of neutrino oscillations and the problems of dark matter and…
A desirable feature of models with large extra dimensions and a TeV range string scale is the possibility to understand an ultralight sterile neutrino needed for a simultaneous understanding of solar, atmospheric and LSND results as a…
We investigate quantitatively the extent to which having a primordial leptonic asymmetry (n_nu \neq n_nubar) relaxes the bounds on light sterile neutrinos imposed by BBN and LSS. We adopt a few assumptions that allow us to solve the…
The neutrino oscillations are studied in the framework of the minimal supersymmetric SO(10) model with Type-III see-saw mechanism by additionally introducing a number of SO(10) singlet neutrinos. The light Majorana neutrino mass matrix is…
Light sterile neutrinos have been introduced as an explanation for a number of oscillation signals at $\Delta m^2 \sim 1$ eV$^2$. Neutrino oscillations at relatively short baselines provide a probe of these possible new states. This paper…
The matter effects for solar neutrino oscillations are studied in a general scheme with an arbitrary number of sterile neutrinos, without any constraint on the mixing, assuming only a realistic hierarchy of neutrino squared-mass differences…
Neutrino physics is nowadays receiving more and more attention as a possible source of information for the long-standing problem of new physics beyond the Standard Model. The recent measurement of the third mixing angle theta13 in the…
We suggest a simple modification of the maximal mixing scenario (with $S_3$ permutation symmetry) for three light neutrinos. Our neutrino mass matrix has smaller permutation symmetry $S_{2}$ ($\nu_{\mu} \leftrightarrow \nu_{e}$), and is…
A sterile neutrino is a well motivated minimal new physics model that leaves an imprint in neutrino oscillations. Over the last two decades, a number of hints pointing to a sterile neutrino have emerged, many of which are pointing near…
The smallness of the $\theta_{13}$ mixing angle as observed in neutrino oscillation experiments can be understood through an approximated $\mu - \tau$ exchange symmetry in the neutrino mass matrix. Using recent oscillation neutrino data,…
We discuss a model where a mixed warm and hot keV neutrino dark matter rises naturally. We arrange active and sterile neutrinos in the same $SU(3)_L$ multiplet, with the lightest sterile neutrino being dark matter. The other two heavy…
We examine the potential for a ``natural'' three-neutrino mixing scheme to satisfy available data and astrophysical arguments. By ``natural'' we mean no sterile neutrinos, and a neutrino mass hierarchy similar to that of the charged…