SUSY effects on the exclusive semi-leptonic decays B→πτ+τ−B \to \pi \tau^+ \tau^- and B→ρτ+τ−B \to \rho \tau^+ \tau^-

In this paper we study the polarization asymmetries of the final state lepton in the radiative dileptonic decay of B meson (\bsllg) in the framework of Minimal Supersymmetric Standard Model (MSSM) and various other unified models within the framework of MSSM e.g. mSUGRA, SUGRA (where condition of universality of scalar masses is relaxed) etc. Lepton polarization, in addition of having a longitudinal component (\pl), can have two other components, \pt and \pn, lying in and perpendicular to the decay plane, which are proportional to \ml and hence are significant for final state being $\mu^+ ~ \mu^-$ or $\tau^+ \~\tau^-$. We analyse the dependence of these polarization asymmetries on the parameters of the various models.Comment: version accepted for publication in Phys. Rev. D. Few refrences and two tables adde

Lepton number violation in Little Higgs model

In this note we examine the constraints imposed by muon anomalous magnetic moment ($(g-2)_\mu$) and $\mu^- \to e^+ e^- e^-$ on lepton number violating (LNV) couplings of the triplet Higgs in Little Higgs (LH) model.Comment: revtex4.0 file, 5 pages including 8 eps figures, version to appear in Phys. Rev.

The effects of enhanced Z penguins on lepton polarizations in B→Xsℓ+ℓ−B \to X_s \ell^+ \ell^-

The sensitivity of the $B \to \pi K$ mode to electroweak penguins and the recent experimental data for the $B \to \pi \pi$, $\pi K$ modes has given rise to what is known as the ``$B \to \pi K$ puzzle''. Recently it has been observed that this {\sl puzzle} can be resolved by considering the new physics which can enter via $Z^0$ penguins. In this note we analyze the effect of this enhanced $Z^0$ penguins on the lepton polarization asymmetries of $b \to s \ell^+ \ell^-$.Comment: Published versio

Neutrino Anomalies in an Extended Zee Model

We discuss an extended $SU(2)\times U(1)$ model which naturally leads to mass scales and mixing angles relevant for understanding both the solar and atmospheric neutrino anomalies. No right-handed neutrinos are introduced in the model.The model uses a softly broken $L_e-L_{\mu}-L_{\tau}$ symmetry. Neutrino masses arise only at the loop level. The one-loop neutrino masses which arise as in the Zee model solve the atmospheric neutrino anomaly while breaking of $L_e-L_{\mu}-L_{\tau}$ generates at two-loop order a mass splitting needed for the vacuum solution of the solar neutrino problem. A somewhat different model is possible which accommodates the large-angle MSW resolution of the solar neutrino problem.Comment: 11 pages including 2 figures; a reference added and text changed accordingl