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Related papers: B -> X_d gamma and constraints on new physics

200 papers

We update the Standard-Model predictions for several quantities related to $B_s - \bar B_s$ and $B_d - \bar B_d$ mixing. The mass and width differences in the $B_s$ system read $ \Delta M_s^{\rm SM} = (17.3 \pm 2.6) ps^{-1}$ and $\Delta…

High Energy Physics - Phenomenology · Physics 2011-11-10 Alexander Lenz , Ulrich Nierste

Based on the low-energy effective Hamiltonian with the generalized factorization, we calculate the new physics contributions to branching ratios and CP-violating asymmetries of the charmless hadronic decays $B_s \to h_1 h_2$ in the standard…

High Energy Physics - Phenomenology · Physics 2009-10-31 Dong Zhang , Zhenjun Xiao , Chong Sheng Li

The present paper deals with a next-to-leading order analysis of the radiative $B \to K^* \gamma$ decay. Working in the PQCD approach developed by Szczepaniak {\it et al.}, we compute the correction, coming from a single gluon exchange with…

High Energy Physics - Phenomenology · Physics 2007-05-23 Marina-Aura Dariescu , Ciprian Dariescu

Combining our results for various O(alpha_s^2) corrections to the weak radiative B-meson decay, we are able to present the first estimate of the branching ratio at the next-to-next-to-leading order in QCD. We find BR(B -> X_s gamma) = (3.15…

We review and update the constraints on the parameters of the quark flavour mixing matrix $V_{CKM}$ in the standard model and estimate the resulting CP asymmetries in $B$ decays, taking into account recent experimental and theoretical…

High Energy Physics - Phenomenology · Physics 2010-11-23 A. Ali , D. London

In a recently proposed extension of the Standard Model with a compact extra dimension of size R we compute the leading corrections, of relative order (m_t R)^2, to the Branching Ratio B -> X_s gamma. For 1/R = 370 \pm 80 GeV, the branching…

High Energy Physics - Phenomenology · Physics 2009-11-07 Riccardo Barbieri , Giacomo Cacciapaglia , Alessandro Romito

We calculate the branching ratios of $B_{s,d}\to \gamma \gamma$ decay in the sequential fourth generation model. We find that the theoretical values of the branching ratios, ${\rm BR}(B_{s}\to\gamma\gamma)$, including the contributions of…

High Energy Physics - Phenomenology · Physics 2007-05-23 W. J. Huo , C. D. Lu , Z. J. Xiao

We analyse the CP asymmetry for B_{s} -->\gamma\gamma in the two Higgs doublet model with tree level flavor changing currents (model III) and three Higgs doublet model with O_2 symmetry in the Higgs sector, including O_{7} type long…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Boz , E. Iltan

In this paper, we calculate the branching ratios and CP-violating asymmetries for $B_{s}\to \rho^\pm K^\mp$, $B_{s}\to\rho^{0}\bar{K}^0 $ and $B_{s}\to\omega\bar{K}^0$ decays in the perturbative QCD (pQCD) factorization approach. The…

High Energy Physics - Phenomenology · Physics 2008-11-26 Zhen-jun Xiao , Xin-fen Chen , Dong-qin Guo

We study the decay B\to X_s\gamma in a minimal extension of the standard model with extra up- and down-type quarks whose left- and right-handed components are both SU(2) singlets. Constraints on the extended Cabibbo-Kobayashi-Maskawa matrix…

High Energy Physics - Phenomenology · Physics 2009-10-31 Mayumi Aoki , Eri Asakawa , Makiko Nagashima , Noriyuki Oshimo , Akio Sugamoto

We present measurements of branching fractions and CP asymmetries of several B- -> D(*)0 K(*)- decays, with the D(*)0 decaying to CP-even, CP-odd, and flavor eigenstates, that can constrain the CP angle gamma as well as the amplitude ratio…

High Energy Physics - Experiment · Physics 2009-04-02 Giampiero Mancinelli

The charm-loop contribution to B -> Xs gamma is found to be numerically dominant and very stable under logarithmic QCD corrections. The strong enhancement of the branching ratio by QCD logarithms is mainly due to the b-quark mass evolution…

High Energy Physics - Phenomenology · Physics 2008-11-26 Paolo Gambino , Mikolaj Misiak

We present an update on total and partial branching fractions and on CP asymmetries in the semi-inclusive decay B -> Xs l+l-. Further, we summarize our results on branching fractions and CP asymmetries for semi-inclusive and fully-inclusive…

High Energy Physics - Experiment · Physics 2015-03-10 G. Eigen , representing the BABAR collaboration

The experimental and theoretical status of the inclusive decay B -> X_s gamma is briefly summarized. Results from a very recent theoretical analysis are reported. An ~11% increase in the SM prediction for BR[ B -> X_s gamma] is found after…

High Energy Physics - Phenomenology · Physics 2007-05-23 Mikolaj Misiak

The photon spectrum in B->X_{s,d} \gamma decay, where X_s(d) is any strange (non-strange) hadronic state, is studied using data samples of $e^+e^- \rightarrow \Upsilon(4S) \to B B-bar decays collected by the Babar and Belle experiments.…

High Energy Physics - Experiment · Physics 2011-02-10 Wenfeng Wang

We present a theoretical reappraisal of the branching ratios and CP asymmetries for the decays $ B \to X_q \ell^+ \ell^-$, with $q=d,s$, taking into account current theoretical uncertainties in the description of the inclusive decay…

High Energy Physics - Phenomenology · Physics 2011-09-13 A. Ali , G. Hiller

The dominant theoretical uncertainty in extracting |V_td/V_ts| from the ratio of branching ratios R=B(B->(rho,omega)gamma)/B(B->K* gamma) is given by the ratio of form factors xi=T_1^{B->K*}(0)/T_1^{B->rho}(0). We re-examine xi in the…

High Energy Physics - Phenomenology · Physics 2011-03-23 Patricia Ball , Roman Zwicky

Based on the latest experimental data of $B \to \pi\pi$ and $\pi K$ modes, a model-independent analytical analysis is presented. The CP-averaged branching ratio difference $\Delta R = R_c - R_n$ in $B\to \pi K$ decays with $R_c =…

High Energy Physics - Phenomenology · Physics 2008-11-26 Yue-Liang Wu , Yu-Feng Zhou , Ci Zhuang

With the wealth of new data from the B-factories, b -> d penguin decays become available for study, in addition to their b -> s counterparts that have proven an indespensable tool for the exploration of new-physics effects in flavour…

High Energy Physics - Phenomenology · Physics 2007-05-23 Robert Fleischer , Stefan Recksiegel

In the two-quark model supposition for $K_0^{*}(1430)$, which can be viewed as either the first excited state (scenario I) or the lowest lying state (scenario II), the branching ratios and the direct CP-violating asymmetries for decays…

High Energy Physics - Phenomenology · Physics 2011-06-07 Zhi-Qing Zhang