62,073 research outputs found

    Consequences of R-Parity violating interactions for anomalies in Bˉ→D(∗)τνˉ\bar B\to D^{(*)} \tau \bar \nu and b→sμ+μ−b\to s \mu^+\mu^-

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    We investigate the possibility of explaining the enhancement in semileptonic decays of Bˉ→D(∗)τνˉ\bar B \to D^{(*)} \tau \bar \nu, the anomalies induced by b→sμ+μ−b\to s\mu^+\mu^- in Bˉ→(K,K∗,ϕ)μ+μ−\bar B\to (K, K^*, \phi)\mu^+\mu^- and violation of lepton universality in RK=Br(Bˉ→Kμ+μ−)/Br(Bˉ→Ke+e−)R_K = Br(\bar B\to K \mu^+\mu^-)/Br(\bar B\to K e^+e^-) within the framework of R-parity violating (RPV) MSSM. Exchange of down type right-handed squark coupled to quarks and leptons yield interactions which are similar to leptoquark induced interactions that have been proposed to explain the Bˉ→D(∗)τνˉ\bar B \to D^{(*)} \tau \bar \nu by tree level interactions and b→sμ+μ−b\to s \mu^+\mu^- anomalies by loop induced interactions, simultaneously. However, the Yukawa couplings in such theories have severe constraints from other rare processes in BB and DD decays. Although this interaction can provide a viable solution to R(D(∗))R(D^{(*)}) anomaly, we show that with the severe constraint from Bˉ→Kννˉ\bar B \to K \nu \bar \nu, it is impossible to solve the anomalies in b→sμ+μ−b\to s \mu^+\mu^- process simultaneously.Comment: RevTex, 13 pages, three figures. In our earlier version, we had neglected a contribution to C^{NP}_9 and obtained erroneous conclusions which we have corrected them in this versio

    Triple Neutral Gauge Boson Couplings in Noncommutative Standard Model

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    It has been shown recently that the triple neutral gauge boson couplings are not uniquely determined in noncommutative extension of the Standard Model (NCSM). Depending on specific schemes used, the couplings are different and may even be zero. To distinguish different realizations of the NCSM, additional information either from theoretical or experimental considerations is needed. In this paper we show that these couplings can be uniquely determined from considerations of unification of electroweak and strong interactions. Using SU(5) as the underlying theory and integrating out the heavy degrees of freedom, we obtain unique non-zero new triple γγγ\gamma\gamma\gamma, γγZ\gamma \gamma Z, γZZ\gamma ZZ, ZZZZZZ, γGG\gamma GG, ZGGZGG and GGGGGG couplings at the leading order in the NCSM. We also briefly discuss experimental implications.Comment: 8 pages, Latex, no figur

    Centers and Cocenters of 00-Hecke algebras

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    In this paper, we give explicit descriptions of the centers and cocenters of 00-Hecke algebras associated to finite Coxeter groups.Comment: 13 pages, a mistake in 4.2 is correcte

    A Study of Some Methods for Measuring CKM CP Violating Phases

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    We study the influence of penguin (especially, electroweak penguin) effects on some methods of measuring the angles α\alpha, β\beta, and γ\gamma in the CKM unitarity triangle. We use next-to-leading order effective Hamiltonian, and present numerical estimates based on the factorization approximation. We find that some techniques suggested in the literature, especially for α\alpha determination, are not workable in light of the electroweak penguin effects. Nevertheless, there are methods that would work for each angle determination. For angle β\beta we consider B→D+D−B \rightarrow D^{+} D^{-} mode and estimate the penguin contamination. For angle γ\gamma we consider a method based on SU(3) symmetry and carefully consider SU(3) breaking effects. We point out regions in the parameter space where this method could be used reliably.Comment: 25 pages (Latex), 5 PS figs (uuencoded, epsf.tex

    Constraints on the phase γ\gamma and new physics from B→KπB\to K\pi Decays

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    Recent results from CLEO on B→KπB\to K\pi indicate that the phase γ\gamma may be substantially different from that obtained from other fit to the KM matrix elements in the Standard Model. We show that γ\gamma extracted using B→Kπ,ππB\to K\pi, \pi\pi is sensitive to new physics occurring at loop level. It provides a powerful method to probe new physics in electroweak penguin interactions. Using effects due to anomalous gauge couplings as an example, we show that within the allowed ranges for these couplings information about γ\gamma obtained from B→Kπ,ππB\to K \pi, \pi\pi can be very different from the Standard Model prediction.Comment: Revised version with analysis done using new data from CLEO. RevTex, 11 Pages with two figure
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