相关论文: Electron-Neutrino Majorana Mass and Solar Neutrino…
If a family symmetry exists so that all three neutrinos have equal Majorana masses (via the seesaw mechanism), then the breaking of this symmetry from charged-lepton masses (via two-loop double $W$ exchange) implies $\Delta m$ less than…
Assuming the canonical seesaw mechanism together with an SO(3) family symmetry for leptons, broken only by the charged-lepton masses, I show that the three neutrinos of Majorana mass $m_0$ are split radiatively in two loops by a maximum…
Extending the minimal standard model of particle interactions (without right-handed singlet neutrinos) to include a heavy scalar triplet $\xi$ to obtain nonzero Majorana neutrino masses, I derive the following simple realistic connection…
Assuming equal tree-level Majorana masses for the standard-model neutrinos, either from the canonical seesaw mechanism or from a heavy scalar triplet, I discuss how their radiative splitting may be relevant to neutrinoless double beta decay…
We propose a radiative origin of the two mass splittings of three degenerate Majorana neutrinos. It can be achieved by extending the standard model to have the usual effective dimension 5 operators generating SO(3)-invariant tree-level…
Two schemes of mixing of four massive neutrinos with two close neutrino masses separated by a gap of Delta m^2 about 1 eV^2 can accommodate solar, atmospheric and LSND neutrino oscillation data. It is shown that long-baseline nu(e)->nu(x)…
We follow a minimalistic approach to neutrino masses, by introducing a single heavy singlet $N$ into the standard model (or supersymmetric standard model) with a heavy Majorana mass $M$, which couples as a single right-handed neutrino in a…
The mass matrix of three Majorana neutrinos of equal mass is not necessarily proportional to the identity matrix, but expressible in terms of two angles and one phase. We discuss how such a mass matrix may be stable or unstable against…
We present new radiative mechanisms for generating Majorana neutrino masses, within an extension of the standard model that successfully generates radiative charged lepton masses, order by order, from heavy sequential leptons. Only the new…
When three Majorana neutrinos describe the solar and atmospheric neutrino data via oscillations, a nonzero measurement of neutrinoless double beta ($0\nu\beta\beta$) decay can determine the sum of neutrino masses $\sum m_\nu$ if the solar…
Assuming three light neutrinos are Majorana particles, we propose mass matrix ansatz for the charged leptons and Majorana neutrinos with family symmetry $S_{3} $ broken into $S_{1}$ and $S_{2}$, respectively. Each matrix has three…
We examine some patterns of Majorana neutrino mass matrix which is compatible with the phenomenological lepton flavor mixing matrix and non-observation of neutrinoless double beta decay. Imposing $(M_{\nu})_{ee}=0$ for the Majorana neutrino…
Two schemes of mixing of four massive neutrinos with two couples of close neutrino masses separated by a gap of the order of 1 eV can accommodate solar, atmospheric and LSND neutrino oscillation data. It is shown that long-baseline…
We show how nonzero Majorana neutrino masses can be radiatively generated by extending the MSSM with leptoquark chiral multiplets without violating R-parity. It is found that, with these particles, the R-parity conservation does not imply…
The MSW or vacuum oscillation solution of the solar neutrino problem can be reconciled with possible existence of the $(\beta\beta)_{0\nu}$ decay with a half-life corresponding to an effective Majorana mass of the electron neutrino…
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}…
Two-loop radiative mechanism, when combined with an U(1)_{L'} symmetry generated by L_e-L_\mu-L_\tau (=L'), is shown to provide an estimate of \Delta m^2_{\odot}/\Delta m^2_{atm} $\sim$ \epsilon m_e/m_\tau, where \epsilon measures the…
A simple unifying mass matrix is presented for the three active and one sterile neutrinos $\nu_e$, $\nu_\mu$, $\nu_\tau$ and $\nu_s$, using an extension of the radiative mechanism proposed some time ago by Zee. The total…
The vacuum oscillation (VO) solution to the solar anomaly requires an extremely small neutrino mass splitting, Delta m^2_{sol}\leq 10^{-10} eV^2. We study under which circumstances this small splitting (whatever its origin) is or is not…
The mass splittings for the Majorana neutrinos in the exact solution of a particular 3-3-1 gauge model are computed here in detail. Since both $\sin^{2}\theta_{13}\simeq0$ and the mass splittings ratio $r_{\Delta}\simeq0.033$ are taken into…