相关论文: Mass Pattern of the SM Fermions: Flavor Democracy …
A simple breaking of the subnuclear democracy of the quarks leads to a mixing between the second and the third family, in agrement with observation. Introducing the mixing between the first and the second family, one finds an interesting…
It is argued with the help of an illustrative model, that the inter--species hierarchy among the fermion masses and the quark mixing angles can be accommodated naturally in the standard model with (approximate) flavor democracy provided…
There are strong arguments favoring the Flavor Democracy hypothesis (or the Democratic Mass Matrix approach) within the Standard Model framework. However, the large mass of the top quark ($m_t >> m_b, m_\tau$) poses an obstacle to the…
Flavor democracy broken in the fermion mass matrix by means of small perturbations can give rise to hierarchical fermion masses. We study the breaking of the $S^L_3 \times S^R_3$ symmetry associated with democratic mass matrices to a…
The flavor democracy hypothesis was introduced in seventies taking in mind three Standard Model (SM) families. Later, this idea was disfavored by the large value of the t-quark mass. In nineties the hypothesis was revisited assuming that…
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,…
We apply the discrete S_3 flavor symmetry to both lepton and quark sectors of the standard model extended by introducing one Higgs triplet and realizing the type-II seesaw mechanism for finite neutrino masses. The resultant mass matrices of…
The observed hierarchy of the quark masses is interpreted as a signal for an underlying ``subnuclear democracy'' as the relevant symmetry of the quark mass terms. A simple breaking of the symmetry leads to a mixing between the second and…
We give an overview of recent progress in the study of fermion mass and flavor mixing phenomena. The hints exhibited by the quark and lepton mass spectra towards possible underlying flavor symmetries, from which realistic models of mass…
In the Standard Model, Yukawa couplings parametrize the fermion masses and mixing angles with the exception of neutrino masses. The hierarchies and apparent regularities among the quark and lepton masses are, however, otherwise a mystery.…
We present a supersymmetric flavour model based on the T' discrete group, which explains fermion masses and mixings. The flavour symmetry, acting in the supersymmetric sector, provides well defined sfermion mass matrices and the resulting…
Building an organized Yukawa structure of quarks and leptons is an essential mission to understand fermion mass hierarchy and flavor mixing in particle physics. Inspired by the similarity of CKM and PMNS mixings, a common mass pattern for…
We investigate a seesaw type mass matrix $M_f\simeq m_L M_F^{-1} m_R$ for quarks and leptons, $f$, under the assumptions that the matrices $m_L$ and $m_R$ have common structures for the quarks and leptons, and that the matrix $M_F$…
The democratic approach to account for fermion masses and mixing is known to be successful not only in the quark sector but also in the lepton sector. Here we extend this ansatz to supersymmetric standard models, in which the K\"ahler…
The potential of $\mu ^{+}\mu ^{-}$ colliders to investigate the fourth SM family fermions predicted by flavour democracy has been analyzed. It is shown that muon colliders are advantageous for both pair production of fourth family fermions…
Considering the hierarchical structure of fermionic masses and the fermionic flavor mixing puzzles in the Standard Model, we propose to relate them by the see-saw mechanism, i.e. only the third generation of quarks and charged leptons…
We impose $O(3)_L\times O(3)_R$ flavor symmetry in the supersymmetric standard model. Three lepton doublets $\ell_i$ transform as an $O(3)_L$ triplet and three charged leptons $\bar e_i$ as an $O(3)_R$ triplet, while Higgs doublets $H$ and…
Flavor Democracy Hypothesis favors existence of iso-singlet quarks and vector-like charged leptons. Their observation at future colliders could shed light on the nature of mass and mixing patterns of known leptons and quarks, as well as…
Present situation in the flavour mixing of quarks and leptons is briefly reviewed and a new approach called the Minimal Flavour Mixing (MFM) is considered in detail. According to MFM the whole of the flavour mixing is basically determined…
The flavor puzzles remain among the most compelling open questions in particle physics. The striking hierarchies observed in the masses and mixing of charged fermions define the Standard Model (SM) flavor puzzle, a profound structural…