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Related papers: Recent Developments in Bbar -> X_s gamma

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We demonstrate, by an explicit one-loop calculation, that at leading twist the nonperturbative effects in B -> gamma l nu, B -> gamma gamma and B -> gamma l+ l- radiative decays are contained in a common multiplicative factor…

High Energy Physics - Phenomenology · Physics 2009-10-09 S. Descotes-Genon , C. T. Sachrajda

We discuss exclusive radiative decays in QCD factorization within the Standard Model. In particular, we consider the decays B -> V gamma, with a vector meson K* or rho in the final state, and the double radiative modes B_s -> gamma gamma…

High Energy Physics - Phenomenology · Physics 2007-05-23 Stefan W. Bosch

In this paper we take the first step towards a complete next-to-next-to-leading logarithmic (NNLL) calculation of the inclusive decay rate for $B \to X_s\gamma$. We consider the virtual corrections of order $\alphas^2 n_f$ to the matrix…

High Energy Physics - Phenomenology · Physics 2008-11-26 Kay Bieri , Christoph Greub , Matthias Steinhauser

Recent BABAR and Belle results on rare B decays involving photons or lepton pairs are reviewed. New preliminary limits from both experiments for B-->rho gamma and B-->omega gamma, and from BABAR for B --> K nu nu and B --> tau nu are…

High Energy Physics - Experiment · Physics 2007-05-23 A. M. Eisner

We derive factorization theorems for Lambda_QCD/mb power corrections to inclusive B-decays in the endpoint region, where mX^2 ~mb Lambda_QCD. In B-> Xu e nu our results are for the full triply differential rate. A complete enumeration of…

High Energy Physics - Phenomenology · Physics 2011-01-27 Keith S. M. Lee , Iain W. Stewart

We review and update the branching ratios for the $B \to (\rho,\omega) \gamma$ decays, calculated in the QCD factorization approach in the next-to-leading order (NLO) in the strong coupling $\alpha_s$ and to leading power in $\Lambda_{\rm…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ahmed Ali , Alexander Parkhomenko

The decay $B \to X_s \gamma$ is studied at the Next to Leading Order in QCD in a class of models containing at least two Higgs doublets and with only one charged Higgs boson non-decoupled at low-energy. The two-loop matching condition is…

High Energy Physics - Phenomenology · Physics 2011-01-05 F. Borzumati , C. Greub

We study the (tree-level) weak radiative decays of $B$ mesons. We present a numerical estimate for the inclusive $b \to X_c \gamma (\gamma)$ modes based on the free-quark decay. We then review what is known for the $B \to D^\star \gamma$…

High Energy Physics - Phenomenology · Physics 2008-11-26 Oleg Antipin , G. Valencia

The partial decay rate $\Gamma(Z\to b\bar{b})$ is significantly influenced by the mass of the top quark due to electroweak radiative corrections. The leading $\sim m_t^2$ and the next-to-leading contribution $\sim \ln m_t^2$ are known to be…

High Energy Physics - Phenomenology · Physics 2011-04-20 A. Kwiatkowski , M. Steinhauser

We report recent results in rare B decays. Our focus will be on b -> d gamma and b -> s l^+ l^- transitions. We discuss their impact on the CKM phenomenology and their role within our search for new physics. In particular, we analyse the…

High Energy Physics - Phenomenology · Physics 2014-11-17 Tobias Hurth , Enrico Lunghi

The flavor-changing electromagnetic dipole operator O_7 gives the dominant contribution to the B -> Xs gamma decay rate. We calculate two-loop QCD corrections to its matrix element together with the corresponding bremsstrahlung…

High Energy Physics - Phenomenology · Physics 2013-07-02 I. Blokland , A. Czarnecki , M. Misiak , M. Slusarczyk , F. Tkachov

The factorization properties of the radiative decays B->V gamma are analyzed at leading order in 1/m_b using the soft-collinear effective theory. It is shown that the decay amplitudes can be expressed in terms of a B->V form factor…

High Energy Physics - Phenomenology · Physics 2008-11-26 Thomas Becher , Richard J. Hill , Matthias Neubert

We present general model-independent formulae for the branching ratios and the direct tagged CP asymmetries for the inclusive B -> Xd gamma and B -> Xs gamma modes. We also update the corresponding SM predictions.

High Energy Physics - Phenomenology · Physics 2011-09-13 T. Hurth , E. Lunghi , W. Porod

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 present technical aspects of next-to-next-to-leading order calculations for heavy-to-light decays such as top quark decay, semileptonic b quark decay into a u quark, muon decay, and radiative decays like b -> s gamma. Algebraic reduction…

High Energy Physics - Phenomenology · Physics 2014-11-18 I. Blokland , A. Czarnecki , M. Slusarczyk , F. Tkachov

We present our results for three-loop anomalous dimensions necessary in analyzing $B{\to}X_s\gamma$ decay at the next-to-leading order in QCD. We combine them with other recently calculated contributions, obtaining a practically complete…

High Energy Physics - Phenomenology · Physics 2011-08-01 Konstantin Chetyrkin , Mikolaj Misiak , Manfred Munz

$O(\alpha_s)$ QCD corrections to the inclusive $B \to X_s e^+ e^-$ decay are investigated within the two - Higgs doublet extension of the standard model (2HDM). The analysis is performed in the so - called off-resonance region; the…

High Energy Physics - Phenomenology · Physics 2014-11-17 G. K. Yeghiyan

A new class of enhanced non-perturbative corrections to the inclusive B->X_s+gamma decay rate is identified, which contribute first at order Lambda/m_b in the heavy-quark expansion and cannot be described using a local operator product…

High Energy Physics - Phenomenology · Physics 2008-11-26 Seung J. Lee , Matthias Neubert , Gil Paz

We compute the branching ratio of inclusive $B \to \eta' X_s$ decay based upon the QCD anomaly mechanism: $b\to s+g^*\to s+g+\eta'$. To obtain a reliable $B \to \eta' X_s$ branching ratio, we calculate the $b\to s+g^*$ form factors up to…

High Energy Physics - Phenomenology · Physics 2007-05-23 Guey-Lin Lin

The branching ratio for the $B \to \rho \gamma$ decay in the next-to-leading order (NLO) in the strong coupling $\alpha_s$ and in leading power in $\Lambda_{\rm QCD}/m_B$ is presented. The corrections are combined the hard-vertex,…

High Energy Physics - Phenomenology · Physics 2007-05-23 Alexander Ya. Parkhomenko
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