Related papers: Probing for New Physics in Polarized $\Lambda_b$ d…
Using the most general, model independent form of effective Hamiltonian, the transverse polarization P_T of Lambda in Lambda_b -> Lambda l^+ l^- decay is studied. It is observed that the averaged <P_T> is very sensitive to the existence of…
Rare decays $\Lambda_b \to \Lambda \gamma$ and $\Lambda_b \to \Lambda l^{+} l^{-}$ (l= e, $\mu$) are examined. We use QCD sum rules to calculate the hadronic matrix elements governing the decays. The $\Lambda$ polarization in the decays is…
Double-lepton polarization asymmetries in (Lambda_b -> Lambda l^+ l^-) decay are calculated using a general, model independent form of the effective Hamiltonian. The sensitivities of these asymmetries to the new Wilson coefficients are…
We investigate the rare baryonic exclusive decays of $\Lambda_b\to \Lambda l^+ l^- (l=e,\mu,\tau)$ with polarized $\Lambda $. Under the approximation of the heavy quark effective theory (HQET), in the standard model we derive the…
Using the most general, model independent effective Hamiltonian, the rare B_s ->\gamma \nu \bar{\nu} decay with polarized photon is studied. The sensitivity of the branching ratio and photon polarization to the new Wilson coefficients are…
A comprehensive study of the angular distributions in the bottom-baryon decays $\it{\Lambda}^\mathrm{0}_b\to\it{\Lambda}_c^+ h^-(h=\pi, K)$, followed by $\it{\Lambda}_c^+\to\it{\Lambda} h^+$ with $\it{\Lambda}\to \it{p} \pi^-$ or…
I review the signals for New Physics in CP-violating measurements in B and Lambda_b decays. I also discuss ways of identifying this New Physics, should such a signal be found.
We study the polarized $\Lambda_b$ baryon semileptonic decay $\Lambda_b \to \Lambda_cl{\bar\nu}$ using perturbative QCD factorization theorem. In this approach heavy baryon transition form factors are expressed as the convolutions of hard…
The experimental studies of the observables associated with the $b \rightarrow c$ transitions in the semileptonic $B-$ meson decays at BaBar, Belle and LHCb have shown some deviations from the Standard Model (SM) predictions, consequently,…
Using the general, model independent form of the effective Hamiltonian, the general expressions of the longitudinal, normal and transversal polarization asymmetries for (l^-) and (l^+) and combinations of them for the exclusive (B -> K l^+…
One of the most pragmatic ways to look for the effects of New Physics at low energy scales is to study a detailed angular distribution of various decay modes, and in particular those based on $b\to c\ell\bar \nu_\ell$. In this paper we…
A complete study of the angular distributions of the processes, $\Lambda_b \to {\Lambda} V(1^-)$, with $\Lambda \to p {\pi}^-$ and $V (J/{\Psi}) \to {\ell}^+ {\ell}^-$ or $V ({\rho}^0,\omega) \to {\pi}^+ {\pi}^-,$ is performed. Emphasis is…
We study unparticle physics effects in (Lambda_b -> Lambda + missing energy) decay with polarized $\Lambda_b$ and $\Lambda$ baryons. The sensitivity of the branching ratio of this decay and polarizations of (Lambda_b) and (Lambda) baryons…
We present a systematic analysis for the rare baryonic exclusive decays of $\Lambda_b\to\Lambda l^+ l^- (l=e,\mu,\tau)$. We study the differential decay rates and the di-lepton forward-backward, lepton polarization and various CP…
The rare decay B -> K* (-> K pi) mu+ mu- is regarded as one of the crucial channels for B physics as the polarization of the K* allows a precise angular reconstruction resulting in many observables that offer new important tests of the…
Rare Lambda_b -> Lambda l^+ l^- decay is investigated in framework of general two Higgs doublet model, in which a new source of CP violation exists (model III). The polarization parameter, CP asymmetry and decay width are calculated. It is…
A study of the decay channels Lambda_{b}-->Lambda V, where V is a vector meson (1^-), has been done by putting together kinematical and dynamical analysis. An intensive use of the helicity formalism is involved on the kinematical side,…
We discuss a few possible strategies for measuring the polarization of the $\Lambda_{\mathrm{b}}$ baryons produced in $e^+e^-$-annihilation at the $\mathrm{Z}$ resonance through their inclusive semileptonic decays. After reviewing the…
It is generally believed that the decay mode $B\to K^*\ell^+\ell^-$ is one of the best modes to search for physics beyond the standard model. The angular distribution enables the independent measurement of several observables as a function…
Angular asymmetries have been measured in polarized Z0 decays to bbg collected by the SLD experiment at the SLC. A high purity bbg event sample is selected by utilizing B lifetime information given by the SLD CCD pixel vertex detector and…