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Related papers: Electroweak radiative corrections to b --> s gamma

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We compute the complete two-loop O(alpha) Wilson coefficients relevant for radiative decays of the B meson in the SM. This is a necessary step in the calculation of the O(alpha alpha_s^n ln^n m_b/M_W) corrections and improves on our…

High Energy Physics - Phenomenology · Physics 2009-11-07 Paolo Gambino , Ulrich Haisch

We compute the two-loop electroweak corrections to the radiative decays of the B meson in the SM. Electroweak effects reduce the Wilson coefficient C_7^eff(mw) by 2.6% for a light Higgs boson of about 100 GeV and are less important for a…

High Energy Physics - Phenomenology · Physics 2009-10-31 Paolo Gambino , Ulrich Haisch

We report recent theoretical progress in the analysis of radiative corrections in inclusive rare B-decays. In view of the B-factories, currently under construction at SLAC and KEK, and of the upgraded CESR experiment, the experimental…

High Energy Physics - Phenomenology · Physics 2011-01-05 C. Greub , T. Hurth

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

Using the asymptotic-expansion technique, we compute the dominant two-loop electroweak corrections, of O(G_F m_t^2), to production and decay via a pair of photons or gluons of the CP-odd Higgs boson A^0 in a two-Higgs-doublet model with…

High Energy Physics - Phenomenology · Physics 2008-11-26 Joachim Brod , Frank Fugel , Bernd A. Kniehl

We review the theoretical understanding of the branching ratio and photon-energy spectrum in B -> Xs gamma decays at next-to-leading order in QCD, including consistently the effects of Fermi motion. For the Standard Model, we obtain B(B ->…

High Energy Physics - Phenomenology · Physics 2007-05-23 Matthias Neubert

We present upgraded theoretical predictions for inclusive and exclusive radiative decays of {\it B} mesons. Our results include those next-to-leading order corrections that have already been computed. Our best estimates in the Standard…

High Energy Physics - Phenomenology · Physics 2009-10-28 M. Ciuchini , E. Franco , G. Martinelli , L. Reina , L. Silvestrini

We investigate the two loop electroweak corrections to B meson rare decays $\bar B\rightarrow X_s\gamma$ and $B_s^0\rightarrow \mu^+\mu^-$ in the minimal supersymmetry standard model (MSSM) extension with two triplets and one singlet…

High Energy Physics - Phenomenology · Physics 2023-11-21 Hai-Xiang Chen , Sheng-Kai Cui , Ning-Yu Zhu , Zhao-Yang Zhang , Huai-Cong Hu

We calculate the full two-loop electroweak matching corrections to the operator governing the decay B_q --> l^+ l^- in the Standard Model. Their inclusion removes an electroweak scheme and scale uncertainty of about 7% of the branching…

High Energy Physics - Phenomenology · Physics 2014-02-26 Christoph Bobeth , Martin Gorbahn , Emmanuel Stamou

By combining a recent estimate of the total B-->X_s gamma branching fraction at O(alpha_s^2) with a detailed analysis of the effects of a cut E_gamma>1.6GeV on photon energy, a prediction for the partial B-->X_s gamma branching fraction at…

High Energy Physics - Phenomenology · Physics 2008-11-26 Thomas Becher , Matthias Neubert

We present an updated next-to-leading order analysis of the B -> X_s gamma branching ratio and photon spectrum, including consistently the effects of Fermi motion in the heavy-quark expansion. For the Standard Model, we obtain B(B -> X_s…

High Energy Physics - Phenomenology · Physics 2011-09-13 A. L. Kagan , M. Neubert

The complete set of two-loop electroweak corrections to the decay width of the Higgs boson into two photons is presented. Two-loop contributions involving weak bosons and the top quark are computed in terms of an expansion in the Higgs…

High Energy Physics - Phenomenology · Physics 2010-04-05 Giuseppe Degrassi , Fabio Maltoni

Improved predictions for the Z-boson decay width and the hadronic Z-peak cross-section within the Standard Model are presented, based on a complete calculation of electroweak two-loop corrections with closed fermion loops. Compared to…

High Energy Physics - Phenomenology · Physics 2014-01-24 A. Freitas

Full O(alpha) electroweak corrections for gamma-gamma-> W+W- are calculated including virtual corrections, soft and hard real photon and Z-boson emission. The corrections are quite large ranging from -2.5% at 500 GeV to -18% at 2 TeV,…

High Energy Physics - Phenomenology · Physics 2009-10-30 G. Jikia

Recently exact results for the complete fermionic two-loop contributions to the prediction for the W-boson mass from muon decay in the electroweak Standard Model have been published [hep-ph/0007091]. This paper illustrates the techniques…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. Freitas , W. Hollik , W. Walter , G. Weiglein

I review the NLO QCD calculations of the branching ratio for B--> X_s gamma in the SM. Including the leading electromagnetic corrections, one obtaines BR(B-> X_s gamma)=(3.32 +- 0.30)*10^{-4}. Confronting theory with the newest data, an…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. Greub

A simple relativistic model of heavy-light mesons is applied to the rare decay B -> K* gamma in the standard model. We find Gamma(B -> K* gamma)/Gamma(b -> s gamma)=(17 \pm 4)% and BR(B -> K* gamma)=(4.8 \pm 1.9) \times 10^{-5}(V_cb/.04)^2.…

High Energy Physics - Phenomenology · Physics 2009-10-22 B. Holdom , M. Sutherland

We evaluate the O(alpha_em/alpha_s) correction to the rate of B -> X_s gamma decay, i.e. we resum all the 0[ alpha_em ln M_W^2/m_b^2 x (alpha_s ln M_W^2/m_b^2)^n ] corrections for n=0,1,2,... Our calculation differs from the previously…

High Energy Physics - Phenomenology · Physics 2009-10-31 Konrad Baranowski , Mikolaj Misiak

The decay Bs to mu+ mu- is one of the milestones of the flavor program at the LHC. We reappraise its Standard Model prediction. First, by analyzing the theoretical rate in the light of its main parametric dependence, we highlight the…

High Energy Physics - Phenomenology · Physics 2015-06-11 Andrzej J. Buras , Jennifer Girrbach , Diego Guadagnoli , Gino Isidori

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…

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