Related papers: Mini-charged tau neutrinos?
A computation of nucleosynthesis bounds on the masses of long-lived Dirac and Majorana neutrinos is reviewed. In particular an explicit treatment of the ``differential heating'' of the $\nue$ and $\bnue$ ensembles due to the residual…
We investigate a model with an extra $Z_{2}$ gauge symmetry in the Standard Model. We assume that only the scalars and the leptons carry non-zero charge. The symmetry gives a structure to the mass matrix for the neutrinos. With two extra…
Searches for heavy neutrinos often rely on the possibility that the heavy neutrinos will decay to detectable particles. Interpreting the results of such searches requires a particular model for the heavy-neutrino decay. We present a method…
It is generally expected that adding light sterile species would increase the effective number of neutrinos, $N_{eff}$. In this paper we discuss a scenario that $N_{eff}$ can actually decrease due to the neutrino oscillation effect if…
A short review on selected issues related to the problem of neutrino electromagnetic properties is given. After a flash look at the theoretical basis of neutrino electromagnetic form factors, constraints on neutrino magnetic moments and…
The data on atmospheric neutrinos can be explained assuming the existence of oscillations between muon neutrinos and light sterile neutrinos with mixing close to maximal, and Delta_m^2 approximately equal to 3 E-3 (eV^2). This…
Several anomalies in neutrino oscillation experiments point to the existence of a $\sim 1\,$eV sterile neutrino $\nu_s$ mixing with $\nu_e$ at the level of $U_{e4}\cong 0.1$, but such a neutrino is strongly disfavored by constraints on…
We investigate the allowed ranges of masses for an unstable tau neutrino in the context of SO(10) GUT-s. In light of the new nucleosynthesis results we obtain that there is a narrow window for m_{\nu_\tau} where the LEP, neutrino…
If the electron neutrino has an effective nonzero Majorana mass, then neutrinoless double beta decay will occur. However, the latter is possible also with a negligible neutrino mass. We show how this may happen in a simple model of scalar…
We show that under a new U(1) gauge symmetry, which is non-anomalous in the presence of one ``right-handed neutrino'' per generation and consistent with the standard model Yukawa couplings, the most general fermion charges are determined in…
If there is no new physics beyond the TeV energy scale, such as in a theory of large extra dimensions, the smallness of the seesaw neutrino mass, i.e. $m_\nu = m_D^2/m_N$, cannot be explained by a very large $m_N$. In contrast to previous…
Addressing the mass origin and properties of neutrinos is of strong interest to particle physics, baryogenesis and cosmology. Popular explanations involve physics beyond the standard model, for example, the dimension-5 Weinberg operator or…
Contrary to a recent claim, the inferred primordial abundances of the light elements are quite consistent with the expectations from standard big bang nucleosynthesis when attention is restricted to direct observations rather than results…
Neutral currents induced matter oscillations of electroweak-active (anti-)neutrinos to sterile neutrinos can explain the observed motion of pulsars. In contrast to a recently proposed explanation of the pulsar birth velocities based on the…
We study low energy galactic neutrinos in the Milky Way under two fundamentally different descriptions of gravity, showing that neutrinos provide a sensitive probe of gravity underlying nature. If gravity is a quantum interaction, its long…
By combining data from cosmic microwave background (CMB) experiments (including the recent WMAP third year results), large scale structure (LSS) and Lyman-alpha forest observations, we constrain the hypothesis of a fourth, sterile, massive…
Several non-threshold reactions which may be used to detect the cosmic neutrino background are presented. The corresponding cross sections are calculated analytically within the Standard Model. These reactions are sensitive not only to the…
We investigate the possibility of producing neutrinoless double beta decay without having an electron neutrino with a mass in the vicinity of 1 eV. We do so by having a much lighter electron neutrino mix with a much heavier (m > 1 GeV)…
I review the various mechanisms for obtaining nonzero neutrino masses. I focus on the possibility of adding one light singlet neutrino to the three known doublet neutrinos nu_e, nu_mu, and nu_tau to accommodate the totality of…
The well known charge conjugation violating interactions in the Standard Model increase neutrino- and decrease anti-neutrino- nucleon cross sections. This impacts neutrino transport in core collapse supernovae through "recoil" corrections…