Related papers: On Teraelectronvolt Majorana Neutrinos
Assuming the seesaw mechanism for hierarchical neutrino masses, we calculate the heavy neutrino masses under the hypotheses that the mixing in the Dirac leptonic sector is similar to the quark mixing ($V_D \sim V_{CKM}$) and that $M_{\nu}…
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…
There are strong indications for neutrino masses and mixings in the data on solar neutrinos as well as in the observed deficit of muon neutrinos from the atmosphere. The COBE data and other analysis of the large scale structure in the…
Specific class of textures for the Dirac and Majorana mass matrices in the seesaw model leading to a pair of almost degenerate neutrinos is discussed. These textures can be obtained by imposing a horizontal $U(1)$ symmetry. A specific model…
On the basis of a seesaw-type mass matrix model for quarks and leptons, $M_f \simeq m_L M_F^{-1} m_R$, where $m_L\propto m_R$ are universal for $f=u,d,\nu$ and $e$ (up-quark-, down-quark-, neutrino- and charged lepton-sectors), and $M_F$…
In spite of enormous experimental progress in determination of the neutrino parameters, theory of neutrino mass and mixing is still on the cross-roads. Guidelines could be (i) the connection between zero neutrino charges (and therefore a…
We study the generation of neutrino masses in the $SU(3)_W$ electroweak unified theory in $M_4\times S_1/(Z_2\times Z'_2)$ spacetime. By appropriate orbifolding, the bulk symmetry $SU(3)_W$ is broken into $SU(2)_L \times U(1)_Y$ at one of…
We evaluate the predictive power of the neutrino mass matrices arising from seesaw mechanism with heavy Majorana mass matrices subject to texture zero and satisfy a cyclic permutation invariant form to the solar neutrino mixing phenomena.…
One puzzle of neutrino masses and mixings is that they do not exhibit the kind of strong "hierarchy" that is found for the quarks and charged leptons. Neutrino mass ratios and mixing angles are not small. A possible reason for this is…
A large hierarchy of the Dirac masses can result in a small hierarchy for the low energy masses of the active neutrinos. This can happen even if the Majorana masses of right-handed neutrinos are all equal. A realistic description of the…
We review previous work on neutrino mass textures in gauge theories. Such textures may arise as a result of flavour symmetries. In a given theory, it is possible to give a classification of heavy Majorana neutrino mass matrices, assuming…
Extensions of the Standard Model with additional U(1) symmetries can describe the hierarchy of fermion masses and mixing angles, including neutrinos. The neutrino masses and mixings are determined up to a discrete ambiguity corresponding to…
A new mechanism for understanding small neutrino masses using only simple new physics at the TeV scale is proposed. As an application, it is shown how it can naturally lead to the mass hierarchy of the so called bimaximal mixing in the case…
In these lecture notes we present mechanisms for the generation of Majorana neutrino masses and lepton mixing. We consider simple extensions of the Standard Model. Apart from a section about radiative mass generation, we put special…
The problem of Majorana neutrino mass generated in Arkani-Hamed--Dimopoulos-Dvali model with n extra spatial dimensions is discussed. Taking into account constraints on neutrino masses coming from cosmological observations, it is possible…
CP violation in the lepton sector, and other aspects of neutrino physics, are studied within a high scale supersymmetry model. In addition to the sneutrino vacuum expectation values (VEVs), the heavy vector-like triplet also contributes to…
Starting from a complete set of possible parametrisations of the quark-mass matrices that have the maximum number of texture zeros at the grand unification scale, and the Georgi-Jarlskog mass relations, we classify the neutrino spectra with…
A minimal extension of the Standard Model (SM) by a vector-like fermion doublet and three right handed (RH) singlet neutrinos is proposed in order to explain dark matter and tiny neutrino mass simultaneously. The DM arises as a mixture of…
The fact that neutrinos are massive suggests that the minimal supersymmetric standard model (MSSM) might be extended in order to include three gauge-singlet neutrino superfields with Yukawa couplings of the type $H_2 L \nu^c$. We propose to…
Mixing between light and heavy neutrino states has been proposed as an explanation (or partial explanation) for the 3-sigma NuTeV anomaly and the 2-sigma departure of the $Z^0$ invisible width from its expected value. I assume herein that…