Related papers: Three generations mixing and the $\tau$ decay puzz…
Influence of the fourth generation, if ever exists, on the experimentally measurable quantities such as invariant dilepton mass distribution, lepton forward-backward asymmetry, and the ratio (Gamma_L/Gamma_T) of the decay widths when K*…
A theory of tau mesonic decays is proposed. The general formula of the axial-vector currents of mesons is presented. The meson vertices are obtained from an effective chiral theory of mesons. The vertices depend on momentum. Many decay…
Hadronic tau decays belong to the processes that show a resonance-like structure in the axial vector current in the $1-2$ GeV range. This structure, often denoted as the $a_1$ meson, seems to show different properties in different…
Current and upcoming experiments should improve the sensitivity to radiative lepton decays by an order of magnitude. This paper assumes that one of the tau --> (e, mu) gamma decays is observed, and explores the structure and consequences of…
We study the prospect of determining the CP violating phase in $\tau$-lepton Yukawa coupling at the Large Hadron Collider (LHC). While the current run is already exploring the production of a pair of the third generation $\tau$ leptons from…
The residual $\mathbb Z^{23}_2$ ($\mathbb Z^{\mu\tau}_2$) and $\mathbb Z^{12}_2$ ($\mathbb Z^s_2$ or $\overline{\mathbb Z}^s_2$) symmetries can not only apply to the lepton sector, but also explain the mainly $1$--$2$ mixing in the quark…
We analyze the quantum transport equations for supersymmetric electroweak baryogenesis including previously neglected bottom and tau Yukawa interactions and show that they imply the presence of a previously unrecognized dependence of the…
The fermion mass textures are discussed in the context of F-theory SU(5) GUT. The tree-level up, down and charged lepton Yukawa couplings are computed in terms of the integrals of overlapping wavefunctions at the intersection points of…
Recent results from Super Kamiokande suggest $\nu_\mu-\nu_\tau$ mixing and hence lepton flavor violation. In supersymmetric models, this flavor violation may have implications for the pattern of slepton masses and mixings. Possible signals…
We interpret the $B$-lattice flavor framework as a compositeness hierarchy: all three fermion generations are elementary chiral fields, but third-generation Yukawa couplings are undressed ($Q=0$), while lighter generations acquire their…
Inspired by the relation between the hadronic decay of the tau lepton and the electron-positron annihilation into hadrons, we derive new tests of perturbative QCD. We design a set of commensurate scale relations to test the self-consistency…
The presence of a colored scalar that is a weak doublet with fractional electric charges of $|Q|=2/3$ and $|Q|=5/3$ with mass below 1,TeV can provide an explanation of the observed branching ratios in $B \to D^{(*)} \tau \bar \nu$ decays.…
Based on experimental data by the Bell Collaboration, we present a phenomenological analysis of the angular distributions in tau- -->K_S pi-nu_tau decay. Our study shows that the angular analysis could lead to some interesting observables,…
Analytic formulae are given for order alpha_s perturbative QCD corrections to the double differential distribution of the tau lepton energy and the invariant mass of the tau + antineutrino system in semileptonic decays of the bottom quark.…
The role of the a_1(1420) resonance in the three-pion decays of the tau lepton is investigated using a phenomenological model. For all data before 2008, roughly equal fit quality is achieved when the basic a_1(1260) resonance is…
In the context of the inclusive $\tau$-decay, we analyze various forms of perturbative expansions which have appeared as modifications of the original perturbative series. We argue that analytic perturbation theory, which combines…
We propose a flavour structure for the leptonic sector of the Standard Model, based on the idea of universality of Yukawa couplings, which accommodates all the experimental data on neutrino masses and mixing, at the same time predicting…
The most general angular distribution of two or three meson final states from semileptonic decays $\tau\rightarrow \pi\pi\nu$, $K\pi\nu$, $\pi\pi\pi\nu$, $K\pi\pi\nu$, $K\pi\nu$, $KKK\nu$, $\eta\pi\pi\nu,\,\ldots{}$ of polarized $\tau$…
In this talk, we introduce a new scenario of grand unified theory (GUT) with anomalous $U(1)_A$ gauge symmetry, which can explain doublet-triplet splitting, quark and lepton masses and mixing angles. In neutrino sector, the scenario…
Search strategies for the third-generation leptoquarks (LQs) are distinct from other LQ searches, especially when they decay to a top quark and a $\tau$ lepton. We investigate the cases of all TeV-scale scalar and vector LQs that decay to…