Examination of the Resonance Contributions to Dileptonic Rare B-Decays

We analyse the long-distance contribution to $B\to X_s\ell^+\ell^-$ differential decay rate when the momentum dependence of $\psi$ and $\psi'$-$\gamma$ conversion strength is taken into account. The results indicate that the resonance to nonresonance interference in the dilepton invariant mass distribution is substantially reduced.Comment: 10 pages, Latex, one figure (included

Effects Of Kaluza-Klein Excited W On Single Top Quark Production At Tevatron

In extra dimension theories if the gauge bosons of the standard model propagate in the bulk of the extra dimensions then they will have Kaluza-Klein excitations that can couple to the standard model fermions. In this paper we study the effects of the first excited Kaluza-Klein mode of the W on single top production at the Tevatron. We find that the cross section for the single top production can be significantly reduced if the mass of the first Kaluza-Klein excited $W \sim 1$ TeV. Hence, a measurement of the single top production cross section smaller than the standard model prediction would not necessarily imply $V_{tb} <1$ or evidence of extra generation(s) of fermions mixed with the third generation.Comment: Text added, Latex, 16 pages, 3 figures, To appear in Phys. Lett.

Observing b→s μ+μ−b \rightarrow s \, \mu^+ \mu^- Decays at Hadron Colliders

We examine the prospects for observing weak flavour-changing neutral current (FCNC) decays of \B\ mesons at hadron colliders, including effects of anomalous $WWZ$~vertices. Since it is very difficult to measure the inclusive rate B \rightarrow X_s \, \lp \lm one should consider exclusive modes such as \BKsmumu\ and \BKmumu. Even though this requires one to compute hadronic matrix elements, we show that experimentally observable quantities (ratios of decay rates) are not strongly parametrisation dependent. Some possibilities for reducing the theoretical uncertainties from other experimental data are discussed.Comment: 17 pages, uses LaTeX, epsf and uufiles. UCLA/93/TEP/2

Understanding the nature of Ds(2317)D_s(2317) and Ds(2460)D_s(2460) through nonleptonic B Decays

We consider the nonleptonic B decays $B \to D^{(*)} D_s(2317)$ and $B \to D^{(*)} D_s(2460)$, involving the newly discovered $D_s(2317)$ and the $D_s(2460)$ states. We find that experiments indicate disagreement with model calculations of their properties and/or breakdown of the factorization assumption for these decays . We point out that decays involving $B_s$ mesons where the $D_s$ resonances can be produced via the weak decay of the $b$ quark can provide further information about the nature of these newly discovered states. We also propose a model to calculate the two body nonleptonic decays $B \to D^{(*)} D_s(2317)(D_s(2460))$, if the $D_s(2317)$ and $D_s(2460)$ are interpreted as $DK$ and $D^*K$ molecules.Comment: 14 pages LaTeX; additional reference, notational corrections and minor clarifications of tex

Integromic analysis of genetic variation and gene expression identifies networks for cardiovascular disease phenotypes

BACKGROUND - : Cardiovascular disease (CVD) reflects a highly coordinated complex of traits. Although genome-wide association studies have reported numerous single nucleotide polymorphisms (SNPs) to be associated with CVD, the role of most of these variants in disease processes remains unknown. METHODS AND RESULTS - : We built a CVD network using 1512 SNPs associated with 21 CVD traits in genome-wide association studies (at P≤5×10) and cross-linked different traits by virtue of their shared SNP associations. We then explored whole blood gene expression in relation to these SNPs in 5257 participants in the Framingham Heart Study. At a false discovery rate <0.05, we identified 370 cis-expression quantitative trait loci (eQTLs; SNPs associated with altered expression of nearby genes) and 44 trans-eQTLs (SNPs associated with altered expression of remote genes). The eQTL network revealed 13 CVD-related modules. Searching for association of eQTL genes with CVD risk factors (lipids, blood pressure, fasting blood glucose, and body mass index) in the same individuals, we found examples in which the expression of eQTL genes was significantly associated with these CVD phenotypes. In addition, mediation tests suggested that a subset of SNPs previously associated with CVD phenotypes in genome-wide association studies may exert their function by altering expression of eQTL genes (eg, LDLR and PCSK7), which in turn may promote interindividual variation in phenotypes. CONCLUSIONS - : Using a network approach to analyze CVD traits, we identified complex networks of SNP-phenotype and SNP-transcript connections. Integrating the CVD network with phenotypic data, we identified biological pathways that may provide insights into potential drug targets for treatment or prevention of CVD

The Rare Decay B→K∗γB\to K^{\ast}\gamma: A More Precise Calculation

Efforts to predict the rare exclusive decay $B\to K^{\ast}\gamma$ from the well known inclusive decay $b\to s\gamma$ are frustrated by the effect of the large recoil momentum. We show how to reduce the large uncertainty in calculating this decay by relating $B\to K^{\ast}\gamma$ to the semileptonic process $B\to\rho e\bar{\nu}$ using the heavy-quark symmetry in B decays and SU(3) flavor symmetry. A direct measurement of the $q^{2}$-spectrum for the semileptonic decay can provide accurate information for the exclusive rare decay.Comment: 15 pages, UTPT-93-02, in REVTEX with one figure in ep

D∗DπD^*D\pi and B∗BπB^*B\pi couplings in QCD

We calculate the $D^*D\pi$ and $B^*B\pi$ couplings using QCD sum rules on the light-cone. In this approach, the large-distance dynamics is incorporated in a set of pion wave functions. We take into account two-particle and three-particle wave functions of twist 2, 3 and 4. The resulting values of the coupling constants are $g_{D^*D\pi}= 12.5\pm 1$ and $g_{B^*B\pi}= 29\pm 3$. From this we predict the partial width \Gamma (D^{*+} \ra D^0 \pi^+ )=32 \pm 5~ keV . We also discuss the soft-pion limit of the sum rules which is equivalent to the external axial field approach employed in earlier calculations. Furthermore, using $g_{B^*B\pi}$ and $g_{D^*D\pi}$ the pole dominance model for the B \ra \pi and D\ra \pi semileptonic form factors is compared with the direct calculation of these form factors in the same framework of light-cone sum rules.Comment: 27 pages (LATEX) +3 figures enclosed as .uu file MPI-PhT/94-62 , CEBAF-TH-94-22, LMU 15/9

Exclusive Radiative B-Decays in the Light-Cone QCD Sum Rule Approach

We carry out a detailed study of exclusive radiative rare $B$-decays in the framework of the QCD sum rules on the light cone, which combines the traditional QCD sum rule technique with the description of final state vector mesons in terms of the light-cone wave functions of increasing twist. The decays considered are: $B_{u,d} \to K^* +\gamma, B_{u,d}\to \rho+\gamma, B_d\to \omega+\gamma$ and the corresponding decays of the $B_s$ mesons, $B_s\to \phi+\gamma$ and $B_s\to K^*+\gamma$. Based on our estimate of the transition form factor F_1^{B \to K^*\pg}(0) =0.32\pm0.05, we find for the branching ratio $BR(B \to K^* + \gamma) = (4.8\pm 1.5)\times 10^{-5}$, which is in agreement with the observed value measured by the CLEO collaboration. We present detailed estimates for the ratios of the radiative decay form factors, which are then used to predict the rates for the exclusive radiative B-decays listed above. This in principle allows the extraction of the CKM matrix element $|V_{td}|$ from the penguin-dominated CKM-suppressed radiative decays when they are measured. We give a detailed discussion of the dependence of the form factors on the $b$-quark mass and on the momentum transfer, as well as their interrelation with the CKM-suppressed semileptonic decay form factors in $B\to \rho+\ell+\nu$, which we also calculate in our approach.Comment: 32 pages, 10 uuencoded figures, LaTeX, preprint CERN-TH 7118/9

Ward Identities, B-> \rho Form Factors and |V_ub|

The exclusive FCNC beauty semileptonic decay B-> \rho is studied using Ward identities in a general vector meson dominance framework, predicting vector meson couplings involved. The long distance contributions are discussed which results to obtain form factors and |V_ub|. A detailed comparison is given with other approaches.Comment: 30 pages+four postscript figures, an Appendix adde

The CP Asymmetry in b→sl+l−b \to s l^+ l^- Decay

Using the experimental upper bound on the neutron EDM and experimental result on $b\rightarrow s\gamma$ branching ratio we have calculated CP asymmetry and $\Gamma^{2HDM}(b\rightarrow s{\it{l^{+}l^{-}}})/\Gamma^{SM}(b\rightarrow s{\it{l^{+}l^{-}}})$. It is shown that in the invariant dilepton mass $q^{2}$ region $(m_{\psi'}^{2}+0.2\; GeV^{2})<\;q^{2}<\;m^{2}_{b}$ the CP asymmetry is maximal and quite detectable.Comment: 18 pages, 5 postscript figures, LaTeX formatte