59 research outputs found

    Polarized lepton pair forward-backward asymmetries in (B -> K^* l^+ l^-) decay beyond the standard model

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    We study the polarized lepton pair forward-backward asymmetries in (B -> K^* l^+ l^-) decay using a general, model independent form of the effective Hamiltonian. We present the general expression for nine double-polarization forward-backward asymmetries. It is shown that, the study of the forward-backward asymmetries of the doubly-polarized lepton pair is a very useful tool for establishing new physics beyond the standard model.Comment: 29 pages, 18 figures, LaTeX formatte

    Double-Lepton Polarization Asymmetries and Polarized Forward Backward Asymmetries in the Rare b \to s \ell^+ \ell^- Decays in a Single Universal Extra Dimension Scenario

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    We study the double-lepton polarization asymmetries and single and double-lepton polarization forward backward asymmetries of the rare b \to s \ell^+ \ell^- mode within the Standard Model and in the Appelquist-Cheng-Dobrescu model, which is a new physics scenario with a single universal extra dimension. In particular, we examine the sensitivity of the observables to the radius R of the compactified extra-dimension, which is the new parameter in this new physics model.Comment: 20 Pages, 15 Figures and 1 Tabl

    General analysis of CP violation in polarized (b -> d l^+ l^-) decay

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    The CP violating asymmetries in the (b -> d l^+ l^-) decay, when one of the leptons is polarized, is investigated using the most general form of the effective Hamiltonian. The sensitivity of the CP violating asymmetries on the new Wilson coefficients is studied.Comment: 25 pages, 20 figures, LaTeX formatte

    Double-lepton polarizations in (B -> l^+ l^- gamma) decay

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    Double-lepton polarization asymmetries in the (B -> l^+ l^- gamma) decay are calculated using the most general, model independent form of the effective Hamiltonian including all possible forms of the interaction. The dependencies of the asymmetries on new Wilson coefficients are investigated. The detectability the averaged double-lepton polarization asymmetries at LHC is also discussed.Comment: 20 pages, 7 PostScript figures, LaTeX formatte

    Double-lepton polarization asymmetries in the Exclusive (B -> rho l^+ l^-) decay beyond the Standard Model

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    The double-lepton polarization asymmetries in (B -> rho l^+ l^-) decay is analyzed in a model independent framework. The general expressions for nine double-polarization asymmetries are calculated. It is shown that the study of the double-lepton polarization asymmetries proves to be very useful tool in looking for new physics beyond the standard model.Comment: 28 pages, 16 figures, LaTeX formatte

    CP-Conserving Unparticle Phase Effects on the Unpolarized and Polarized Direct CP Asymmetry in bd+b \to d \ell^+\ell^- Transition

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    We examine the unparticle CP-conserving phase effects on the direct CP asymmetry for both polarized and unpolarized lepton in the inclusive bd+b\to d \ell^+ \ell^- transition, where the flavor changing neutral currents are forbidden at tree level but are induced by one-loop penguin diagrams. The averaged polarized and unpolarized CP asymmetries depict strong dependency on the unparticle parameters. In particular, a sizable discrepancy corresponding to the standard model is achieved when the scale dimension value is 1. We see that the unparticle stuff significantly enhances, suppresses or changes the sign of the CP asymmetry depending on the definite value of the scaling dimension d_{\UP}. Especially, when d_{\UP}\sim 1.1 the CP asymmetries vanish.Comment: 10 figures, PRD Published versio

    Exclusive (B -> rho l^+ l^-) decay and Polarized lepton pair forward--backward asymmetries

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    The polarized lepton pair forward-backward asymmetries in (B -> rho l^+ l^-) decay using a general, model independent form of the effective Hamiltonian is studied. The general expression for nine double-polarization forward-backward asymmetries are calculated. The study of the forward-backward asymmetries of the doubly-polarized lepton pair proves to be very useful tool in looking for new physics beyond the standard model.Comment: 23 pages, 12 figures, LaTeX formatte

    Double-lepton polarization asymmetries in the (B -> K l^+ l^-) decay beyond the Standard Model

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    General expressions for the double-lepton polarizations in the (B -> K l^+ l^-) decay are obtained, using model independent effective Hamiltonian, including all possible interactions. Correlations between the averaged double-lepton polarization asymmetries and the branching ratio, as well as, the averaged single-lepton polarization asymmetry are studied. It is observed that, study of the double-lepton polarization asymmetries can serve as a good test for establishing new physics beyond the Standard Model.Comment: 21 pages, 18 figures, LaTeX formatte

    The Effects of Fourth Generation on the double Lepton Polarization in B \rar K \ell^+ \ell^- decay

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    This study investigates the influence of the fourth generation quarks on the double lepton polarizations in B \rar K \ell^+ \ell^- decay. Taking |V_{t's}V_{t'b}|\sim \{0.01-0.03\} with phase about 100^\circ, which is consistent with the b\to s\ell^+\ell^- rate and the B_s mixing parameter Delta m_{B_s}$, we obtain that the double lepton(muon and tau) polarizations are quite sensitive to the existence of fourth generation. It can serve as a good tool to search for new physics effects, precisely, to indirect search for the fourth generation quarks(t', b').Comment: 30 pages, 27 figure

    Double-Lepton Polarization Asymmetries and Branching Ratio in B \rar K_{0}^{*}(1430) l^+ l^- transition from Universal Extra Dimension Model

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    We investigate the B \rar K_{0}^{*}(1430) l^+ l^- transition in the Applequist-Cheng-Dobrescu model in the presence of a universal extra dimension. In particular, we calculate double lepton polarization asymmetries and branching ratio related to this channel and compare the obtained results with the predictions of the standard model. Our analysis of the considered observables in terms of radius RR of the compactified extra-dimension as the new parameter of the model show a considerable discrepancy between the predictions of two models in low 1R\frac{1}{R} values.Comment: 12 Pages, 15 Figures and 1 Tabl
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