相关论文: Universal Seesaw Mass Matrix Model and Neutrino Ph…
Recent development of the universal seesaw mass matrix model is reviewed. The model was proposed in order to explain why quark and lepton masses are so small compared with the electroweak scale \Lambda_L =<\phi_L^0>=174 GeV. However, the…
Neutrino masses and mixings are investigated on the basis of a universal seesaw mass matrix model, in which quark (except for top) and charged lepton mass matrices M_f and neutrino mass matrix M_\nu are given by M_f \simeq m_L M_F^{-1} m_R…
This is a review article about neutrino mass models, particularly see-saw models involving three active neutrinos which are capable of describing both the atmospheric neutrino oscillation data, and the large mixing angle MSW solar solution,…
In the democratic universal seesaw model, the mass matrices are given by \bar{f}_L m_L F_R + \bar{F}_L m_R f_R + \bar{F}_L M_F F_R (f: quarks and leptons; F: hypothetical heavy fermions), m_L and m_R are universal for up- and down-fermions,…
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 $M_F$…
I review promising approaches to neutrino mass models, focussing on three neutrino patterns of neutrino masses and mixing angles, and the corresponding Majorana mass matrices. I discuss the see-saw mechanism, and show how it may be applied…
A seesaw mass matrix model is reviewed as a unification model of quark and lepton mass matrices. The model can understand why top-quark mass m_t is so singularly enhanced compared with other quark masses, especially, why m_t >> m_b in…
A universal seesaw mass matrix model, which gives successful description of quark mass matrix in terms of lepton masses, yields three "sterile" neutrinos \nu^s_{i}, which compose pseudo-Dirac neutrinos \nu_{i\pm}^{ps}\simeq (\nu_{i} \pm…
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 $M_F$ is…
We present a model of neutrino masses combining the seesaw mechanism and strong Dirac mass hierarchy and at the same time exhibiting a significantly reduced hierarchy at the level of active neutrino masses. The heavy Majorana masses are…
It is found that the seesaw mechanism not only explain the smallness of neutrino masses but also account for the large mixing angles simultaneously, even if the unification of the neutrino Dirac mass matrix with that of up-type quark sector…
It is an experimental fact that the mass ratio for the two heavier neutrinos, h = m_3/m_2 < 6, is much smaller than the typical quark and lepton hierarchies, which are O(20-300). We have explored whether this peculiar pattern of neutrino…
A beautiful understanding of the smallness of the neutrino masses may be obtained via the seesaw mechanism, whereby one takes advantage of the key qualitative distinction between the neutrinos and the other fermions: right-handed neutrinos…
A previous short analysis of the seesaw mechanism, based on quark-lepton symmetry, experimental data and hierarchical neutrino spectrum, is enlarged to include small but not zero U_{e3}, inverted mass hierarchy, and the qualitative effect…
We propose a $U(1)_L$ model with $A_4$ symmetry in light of the linear seesaw for majorana neutrino that capable of generating the current lepton and quark mass and mixing patterns. The smallness of Majorana neutrino mass is reproduced…
We suggest an approach to explain the observed pattern of the neutrino masses and mixing which employs the weakly broken quark-lepton symmetry and does not require introduction of an ad hoc symmetry of the neutrino sector. The mass matrices…
We formulate a viable low-scale seesaw model, where the masses for the standard model (SM) charged fermions lighter than the top quark emerge from a universal seesaw mechanism mediated by charged vectorlike fermions. The small light active…
The observation of neutrino oscillations requires new physics beyond the standard model (SM). A SM-like gauge theory with p lepton families can be extended by introducing q heavy right-handed Majorana neutrinos but preserving its SU(2)_L x…
Stimulated by the phenomenological success of the universal seesaw mass matrix model, where the mass terms for quarks and leptons f_i (i=1,2,3) and hypothetical super-heavy fermions F_i are given by \bar{f}_L m_L F_R +\bar{F}_L m_R f_R +…
Based on the "democratic" universal seesaw model, where mass matrices $M_f$ of quarks and leptons f_i (f=u,d,\nu,e; i=1,2,3) are given by a seesaw form M_f\simeq -m_L M_F^{-1} m_R, and m_L and m_R are universal for all the fermion sectors,…