Related papers: Composite Scalars at LEP: Constraining Technicolor…
The diphoton excesses at 750 GeV seen in the LHC data may be the first hint for new physics at the TeV scale. We discuss variations of the model considered earlier, in which one or more diphoton excesses arise from composite pseudo…
The $\mu\tau$-reflection symmetric neutrino mass matrix can accommodate all known neutrino mixing angles, with maximal atmospheric angle fixed, and predicts all the unknown CP phases of the lepton sector but is unable to predict the…
The existence of anomalous electric($\tilde \kappa$) and/or magnetic($\kappa$) dipole moment couplings between the heavy flavor fermions ($c,b,\tau$) and the $Z$ boson can cause significant shifts in the values of several electroweak…
A slowly running technicolor coupling will affect the size of non-oblique corrections to the $Zb\bar b$ vertex from extended technicolor dynamics. We show that while ``walking technicolor'' reduces the magnitude of the corrections, they…
The contributions of the neutral top-pion $\pi_{t}^{0}$ and the non-universal gauge boson $Z'$ predicted by topcolor scenario to the lepton flavor violating $(LFV)$ semileptonic $\tau$ decays $\tau\to lP(V)$ $(P=\pi^{0}, \eta, \eta' $ and $…
We study the decay of the standard model Z boson into unparticle plus a single photon through a one-loop process. As in the anomaly type decay, only the axial-vector part of the Z coupling matching with the vector unparticle and/or the…
The observed pattern of mixing in the neutrino sector may be explained by the presence of a non-Abelian, discrete flavour symmetry broken into residual subgroups at low energies. Many flavour models require the presence of Standard Model…
We suggest the use of a universality-breaking observable based on lepton asymmetries as derived from the left-right asymmetry and the $\tau$ polarization at the $Z$ peak, which can efficiently constrain the parameter space of unified…
Originally thought as clean processes to study the hadronization of the weak currents, semileptonic tau lepton decays can be useful to set constraints on non-standard (NS) weak interactions. In this talk we summarize our recent studies on…
New physics beyond the Standard Model can lead to extra matter effects on neutrino oscillation if the new interactions distinguish among the three flavors of neutrino. In Ref.1, we argued that a long-baseline neutrino oscillation experiment…
New neutral heavy gauge bosons ($Z^\prime$) are predicted within many extensions of the Standard Model. While in case they couple to quarks the LHC bounds are very stringent, leptophilic $Z^\prime$ bosons (even with sizable couplings) can…
We examine the rare decays $B_s\to l^+l^-$ and $B\to Kl^+l^-$ in the framework of the topcolor-assisted technicolor ($TC2$) model. The contributions of the new particles predicted by this model to these rare decay processes are evaluated.…
Measuring the lepton anomalous magnetic moments $(g-2)$ and the rare decays of light pseudoscalar mesons into lepton pairs $P\to l^{+}l^{-} $, serve as important tests of the Standard Model. To reduce the theoretical uncertainty in the…
We analyze the constraints on the the vacuum polarization of the standard model gauge bosons from a minimal set of flavor observables valid for a general class of models of dynamical electroweak symmetry breaking. We will show that the…
Hyperon nonleptonic decays that change strangeness by two units, such as $\Xi\to N\pi$ and $\Omega^-\to nK^-,\Lambda\pi^-,\Sigma^{(*)}\pi$, are highly suppressed in the standard model. Only a few of them have been searched for to date,…
We consider a minimal technicolor model in which the ordinary and technicolor sectors are coupled by a {\it massless} scalar doublet. When technicolor interactions become strong, the resulting technicolor condensate not only breaks the…
Recent LEP searches for Higgs bosons in models other than the Minimal Standard Model and the Minimal Supersymetric Standard Model are reviewed. Limits are presented for Higgs bosons decaying into diphotons or invisible particles, and for…
Natural models of supersymmetry with a gravitino LSP provide distinctive signatures at the LHC. For a neutralino NLSP, sparticles can decay to two high energy photons plus missing energy. We use the ATLAS diphoton search with 4.8 fb^{-1} of…
Tau lepton decays with open strangeness in the final state are measured with the OPAL detector at LEP to determine the strange hadronic spectral function of the tau lepton. The decays T- ->(Kpi)-nu tau, (Kpipi)-nu tau and (Kpipipi) -nu tau…
In topcolor-assisted technicolor models (TC2) the hitherto unconstrained lepton flavor mixing induced by the new gauge boson $Z'$ will lead to the lepton flavor violating productions of $\tau\bar \mu$, $\tau\bar e$ and $\mu\bar e$ in…