Related papers: Fourth generation quark mass limits in CKM-element…
We present three searches for new particles at CDF. First, using 70 pb^-1 of data we search the dijet mass spectrum for resonances. There is an upward fluctuation near 550 GeV (2.6 sigma) with an angular distribution that is adequately…
Using firmly established experimental inputs such as epsilon_K, Delta M_d, Delta M_s, BR(B -> tau nu), gamma, V_cb along with corresponding lattice matrix elements which have been well studied and are in full QCD such as B_K, SU3 breaking…
We summarize the top-quark mass measurements from the CDF and D0 experiments at Fermilab. We combine published Run-I measurements with the most recent Run-II measurements. Taking correlated uncertainties into account the resulting…
CP violation in the CKM mixing is discussed for the case of quark mass degeneracy that is approximate in the quark mass hierarchy limit. Differing from the traditional understanding of CP vanishing for degenerate masses, we find degenerate…
In the light of the top quark discovered very recently by CDF, we investigate the possibility of narrowing down the allowed top quark masses by combining for the first time only two strongest constraints present in the no-scale $SU(5)\times…
An attempt has been made to carry out a detailed analysis of quark mass matrices having structure beyond the minimal texture. In particular, keeping in mind, precision measurements of CKM parameters as well as refinements in the ranges of…
We examine the problem of three generation quark flavor mixing in realistic, superstring derived standard--like models, constructed in the free fermionic formulation. We study the sources of family mixing in these models and discuss the…
A fourth generation of quarks, if it exist, may provide sufficient CP violation for the baryon asymmetry of the Universe. We estimate the neutron electric dipole moment in the presence of a fourth generation, and find it would be dominated…
We propose models to explain the hierarchies of the quark masses and mixing by utilizing the $S_4^\prime$ modular flavor symmetry. The hierarchy is realized by the modulus $\tau$ stabilized at $\mathrm{Im}\,\tau \gg 1$, where the residual…
We discuss $Z$ mediated flavour changing neutral currents within a model where the hierarchical quark and lepton masses are explained via a fourth vector-like family, together with a scalar sector consisting of two Higgs doublets augmented…
We analyse the possibility of describing quark masses, mixing and CP violation in $S'_4$ modular flavour models without flavons. We focus on the case where the closeness of the modulus to the point of residual $\mathbb{Z}^{ST}_3$ symmetry…
CP-PACS and JLQCD collaborations are carrying out a joint project of the 2+1 flavor full QCD simulation. Gauge configurations are generated for the non-perturbatively $O(a)$-improved Wilson quark action and the Iwasaki gauge action using…
We discuss first the flavor mixing of the quarks, using the texture zero mass matrices. Then we study a similar model for the mass matrices of the leptons. We are able to relate the mass eigenvalues of the charged leptons and of the…
Recent measurements like the t tbar gamma production by CDF as well as the Br(B ->Xs gamma) and ACP (B->Xs gamma) are used to constrain the magnetic and electric dipole moments of the top quark. The B->Xs gamma measurements by themselves…
The quark and charged lepton masses and the angles and phase of the CKM mixing matrix are nicely reproduced in a model which assumes SU(3)xSU(3) flavour symmetry broken by the v.e.v.'s of fields in its bi-fundamental representation. The…
We consider the bounds for the values of higgs mass $m_H$ and the mass of the extra quarks and leptons $m_{extra}$ derived from the stability of electroweak vacuum and from the absence of Landau pole in Higgs potential. We find that in the…
Without assuming any specific flavor symmetry and/or any specific mass matrix forms, it is demonstrated that if a flavor symmetry (a discrete symmetry, a U(1) symmetry, and so on) exists, we cannot obtain the CKM quark mixing matrix $V$ and…
We discuss the quark mass matrices in the $A_4$ modular symmetry, where the $A_4$ triplet of Higgs is introduced for each up-quark and down-quark sectors, respectively. The model has six real parameters and two complex parameters in…
The CDF and D0 collaborations have updated their measurements of the mass of the top quark using proton-antiproton collisions at sqrt{s}=1.96TeV produced at the Tevatron. The uncertainties in each of the of top-antitop decay channels have…
In light of the recent CMS analysis on lepton flavor violating (LFV) heavy Higgs searches and updated bounds on various search channels involving neutral and charged scalars, we provide the updated constraints on the Type-III…