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We investigate the form factors of $B_c$ meson into $S$-wave charmonium within the nonrelativistic QCD effective theory and obtain the next-to-leading order relativistic corrections to the form factors, where both the $B_c$ meson and the…

High Energy Physics - Phenomenology · Physics 2017-05-24 Ruilin Zhu , Yan Ma , Xin-Ling Han , Zhen-Jun Xiao

We present the partial branching fraction for inclusive charmless semileptonic B decays and the corresponding value of the CKM matrix element |Vub|, using a multivariate analysis method to access ~90% of the B -> Xu l nu phase space. This…

High Energy Physics - Experiment · Physics 2012-08-27 The Belle Collaboration

The various decay modes of the type $B \to \gamma D^* $ are dynamically different. In general there are factorizable contributions, and there are pole diagrams and pseudoscalar exchange contributions at meson level. The purpose of this…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. O. Eeg J. A. Macdonald Sørensen

We study the loop induced rare decays $B_s(B_d)\to\gamma\nu\bar\nu$ within the standard model. Both constituent quark model and pole model are used and the branching ratios turn out to be of the orders of $10^{-8}$ for $B_s\to \gamma \nu…

High Energy Physics - Phenomenology · Physics 2015-06-25 Cai-Dian Lu , Da-Xin Zhang

We determine, by means of lattice QCD calculations, the local form factors describing the $B_{s}\to \mu^{+}\mu^{-}\gamma$ decay. For this analysis we make use of the gauge configurations produced by the ETM Collaboration with $N_{f}=2+1+1$…

High Energy Physics - Lattice · Physics 2024-02-08 R. Frezzotti , G. Gagliardi , V. Lubicz , G. Martinelli , C. T. Sachrajda , F. Sanfilippo , S. Simula , N. Tantalo

Two-body charmless nonleptonic decays of the B_s meson are studied within the framework of generalized factorization in which factorization is applied to the tree level matrix elements while the effective Wilson coefficients are $\mu$ and…

High Energy Physics - Phenomenology · Physics 2016-08-25 Yaw-Hwang Chen , Hai-Yang Cheng , B. Tseng

Using perturbative QCD, the contribution at the leading twist, leading $\alpha_s$ level, of charm and up quark loops to the decays $B \rightarrow K^* \gamma$ and $B \rightarrow \rho \gamma$ is presented. In the case of $B \rightarrow \rho…

High Energy Physics - Phenomenology · Physics 2010-11-01 J. Milana

Charmless semileptonic decays, ${\bar{B}} \to X_u \ell \bar{\nu}$, are studied in a sample of 232 million $B\bar{B}$ decays recorded with the BaBar detector, in events where the decay of the second $B$ meson is fully reconstructed.…

High Energy Physics - Experiment · Physics 2016-08-31 B. Aubert , BABAR Collaboration

We present preliminary results on $b \to s \gamma$ from the CLEO experiment. An updated result on the branching fraction is reported at $\cal{B}$$(b \to s \gamma) = (3.15 \pm 0.35 \pm 0.32 \pm 0.26)\times 10^{-4}$, where the first…

High Energy Physics - Experiment · Physics 2007-05-23 S. Ahmed , CLEO Collaboration

We calculate the electroweak-like one-loop supersymmetric contributions to the rare and flavor-violating decay of the top quark into a charm quark and a gauge boson: $t->c V$, with $V=\gamma,Z,g$. We consider loops of both charginos and…

High Energy Physics - Phenomenology · Physics 2009-10-30 Jorge L. Lopez , D. V. Nanopoulos , Raghavan Rangarajan

Interference between the photonic dipole operator Q_7 and the current-current operators Q_{1,2} gives one of the most important QCD corrections to the B -> X_s gamma decay rate. So far, the O(alpha_s^2) part of this correction has been…

High Energy Physics - Phenomenology · Physics 2015-03-09 Michal Czakon , Paul Fiedler , Tobias Huber , Mikolaj Misiak , Thomas Schutzmeier , Matthias Steinhauser

We compute non-perturbative contributions to b->s l+ l- that are not explicitly suppressed by powers of the b-quark mass. They are proportional to lambda_2 and arise from an interference between the free-quark amplitude and higher order…

High Energy Physics - Phenomenology · Physics 2011-01-27 Jiunn-Wei Chen , Gautam Rupak , Martin J. Savage

We have calculated inclusive direct CP-asymmetries for charmless B^{+/-} -decays. After summing large logarithms to all orders the CP-asymmetries in Delta S=0 and Delta S=1 decays are found as a_{CP} (Delta S=0) = (2.0 +1.2/-1.0)% and…

High Energy Physics - Phenomenology · Physics 2016-09-06 A. Lenz , U. Nierste , G. Ostermaier

A calculation of the leading isospin-breaking contributions to the B -> K^* gamma decay amplitudes based on the QCD factorization approach is presented. They arise at order Lambda/m_b in the heavy-quark expansion and are due to annihilation…

High Energy Physics - Phenomenology · Physics 2014-11-17 Alexander L. Kagan , Matthias Neubert

We obtain predictions for a number of radiative decays $B_{(s)}\to V\gamma$, $V$ the vector meson, which proceed through the weak-annihilation mechanism. Within the factorization approximation, we take into account the photon emission from…

High Energy Physics - Phenomenology · Physics 2016-01-20 Anastasiya Kozachuk , Dmitri Melikhov , Nikolai Nikitin

It is shown that the inclusive rate of the rare weak radiative decays $B \to X_s \gamma$ contains a series of nonperturbative corrections, whose `short distance' scale is set by $m_c^{-1}$, rather than by $m_b^{- 1}$. The first correction…

High Energy Physics - Phenomenology · Physics 2016-09-06 M. B. Voloshin

We study the $B(B_{s})\rightarrow D_{(s)}(\bar{D}_{(s)})\,T$ and $D_{(s)}^{\ast}(\bar{D}_{(s)}^{*})\,T$ decays in perturbative QCD approach, where T denotes a light tensor meson. In addition to the branching ratios, we also give predictions…

High Energy Physics - Phenomenology · Physics 2012-09-18 Zhi-Tian Zou , Xin Yu , Cai-Dian Lu

The present NLL prediction for the decay rate of the rare inclusive process $\bar B \to X_s \gamma$ has a large uncertainty due to the charm mass renormalization scheme ambiguity. We estimate that this uncertainty will be reduced by a…

High Energy Physics - Phenomenology · Physics 2011-01-05 H. Asatrian , A. Hovhannisyan , V. Poghosyan , C. Greub , T. Hurth

We compute the two-loop BSM contributions to the $h\longrightarrow \gamma\gamma$ decay width in the SM extended with a real triplet of $SU(2)$. We consider scenarios in which the neutral components of doublet and triplet do not mix, so that…

High Energy Physics - Phenomenology · Physics 2025-01-22 Giuseppe Degrassi , Pietro Slavich

We utilize asymptotic Pade-approximant methods to estimate the three-loop order MS bar-scheme coefficients within the inclusive semileptonic b to u decay rate for four and five active quark flavours. The estimates we obtain for the three…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. R. Ahmady , F. A. Chishtie , V. Elias , T. G. Steele