相关论文: Quarks, Squarks and Textures

If supersymmetry exists at low energies, it is necessary to understand why the squark spectrum exhibits sufficient degeneracy to suppress flavor changing neutral currents. In this note, we point out that gauged horizontal symmetries can…

Against the conventional picture that the mass matrix forms in the quark sectors will take somewhat different structures from those in the lepton sectors, on the basis of an idea that all the mass matrices of quarks and leptons have the…

For generic squark masses, box diagrams with squarks and gluinos give unacceptably large contributions to neutral meson ($K$, $B$ and $D$) mixing. The standard solution to this problem is to assume that squarks are degenerate to a very good…

We review recent work on the interplay between broken family symmetries which give rise to approximate texture zeros in the mass matrices of the quarks and leptons and the presence of certain hierarchy patterns in the spectrum of massive…

The smallness of the quark sector parameters and the hierarchy between them could be the result of a horizontal symmetry broken by a small parameter. Such an explicitly broken symmetry can arise from an exact symmetry which is spontaneously…

The supersymmetric contributions to the Flavor Changing Neutral Current processes may be suppressed by decoupling the scalars of the first and second generations. It is known, however, that the heavy scalars drive the stop mass squareds…

It has been known that the supersymmetric flavor changing neutral current problem can be avoided if the squarks take the following mass pattern, namely the first two generations with the same chirality are degenerate with masses around the…

An inverted mass hierarchy in the squark sector, as in so-called "natural supersymmetry", requires non-universal boundary conditions at the mediation scale of supersymmetry breaking. We propose a formalism to define such boundary conditions…

The structure of flavour space is determined by the form of the quark mass matrices in the weak flavour space basis. We examine some matrix textures in the light of flavour permutations symmetry arguments, for three and four families.

Texture matrices are a way of mitigating the redundancy inherent in the description of flavor physics via Yukawa couplings by eliminating some entries in order to identify relevant parameters. A four-zero texture scheme has been used in the…

In a supersymmetric model with hierarchical squark masses we analyze a pattern of flavour symmetry breaking centered on the special role of the top Yukawa coupling and, by extension, of the full Yukawa couplings for the up-type quarks. For…

The mass matrix forms of quarks and leptons are discussed in theory with permutation flavor symmetry. The structure of scalar potential is analyzed in case that electroweak doublet Higgs fields have non-trivial flavor symmetry charges. We…

We argue that flavour mixing, both in the quark and lepton sector, follows the minimal mixing pattern, according to which the whole of this mixing is basically determined by the physical mass generation for the first family of fermions. So,…

It is shown that a gauged SO(3) family symmetry can suppress flavor-changing processes from squark-mass non-degeneracy to an acceptable level. The potentially dangerous SO(3) D-terms can be rendered harmless if the CP-violating phases…

The low-energy sector of QCD with $N_f = 2\!+\!1$ dynamical quark flavors at non-vanishing chemical potential and temperature is studied with a non-perturbative functional renormalization group method. The analysis is performed in different…

QCD lattice simulations with 2+1 flavours (when two quark flavours are mass degenerate) typically start at rather large up-down and strange quark masses and extrapolate first the strange quark mass and then the up-down quark mass to its…

Using anomalous U(1) symmetry the quark mass texture is determined uniquely. We analyze squark mass spectrum based on the above mass matrices and discuss the possibility to solve the problems of FCNC and CP caused by complex phases of soft…

We propose a mass matrix model that gives a unified description of quark and lepton with the same texture form based on a flavor 2 <-> 3 symmetry. The model is in contrast with the conventional picture that the mass matrix forms in the…

We argue that flavour mixing, both in the quark and charged lepton sector, is basically determined by the lightest family mass generation mechanism. So, in the chiral symmetry limit when the up and down quark masses vanish, all the quark…

We show how a novel fine-tuning problem present in the Standard Model can be solved through the introduction of a single flavour symmetry G, together with three $Q = - 1/3$ quarks, three $Q = 2/3$ quarks, as well as a complex singlet…