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Related papers: The b -> s gamma decay revisited

200 papers

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 give a more complete calculation of $b \to s\gamma $ decay in 2-Higgs doublet model, including leading log QCD corrections from $m_{top}$ to $M_W$ in addition to corrections from $M_{W}$ to $m_b$. The inclusive decay rate in the first…

High Energy Physics - Phenomenology · Physics 2009-10-28 Cai-Dian Lu

We compute the decay rate of the Standard Model Higgs boson to bottom quarks to order $\alpha\alpha_s$. We apply the optical theorem and calculate the imaginary part of three-loop corrections to the Higgs boson propagator using asymptotic…

High Energy Physics - Phenomenology · Physics 2015-11-11 Luminita Mihaila , Barbara Schmidt , Matthias Steinhauser

Decay rates of the B-meson are studied through charmless and strangless transitions into pi, rho, omega and gamma systems. The important features of these modes are their clean signatures. The CLEO II collaboration has recently reported the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Josip Trampetic

We compute the $O(\beta_0 \alpha_s^2)$ QCD corrections to the Standard Model decay $t\rightarrow W^+ b$ as well as the non standard decay $t\rightarrow H^+ b$. We then use our results to compute the BLM scale for these decays, and study the…

High Energy Physics - Phenomenology · Physics 2009-10-28 Thomas Mehen

We compute O(alpha_s) and O(alpha_s^n beta_0^{n-1}) (BLM) corrections to the five structure functions relevant for b->q l nu decays and apply the results to the moments of a few distributions of phenomenological importance. We present…

High Energy Physics - Phenomenology · Physics 2008-11-26 V. Aquila , P. Gambino , G. Ridolfi , N. Uraltsev

We present an estimate of certain higher order corrections to the contribution of the charm triangle loop in the inclusive B -> X_s gamma decay rate, recently discussed by Voloshin. We find that these corrections are minute and hence the…

High Energy Physics - Phenomenology · Physics 2016-08-24 A. K. Grant , A. G. Morgan , S. Nussinov , R. D. Peccei

We calculate the leading logarithmic QCD corrections to the decay B_{s} -->\gamma\gamma in the two Higgs doublet model with tree level flavor changing currents (model III) including O_7 type long distance effects. Further, we analyse the…

High Energy Physics - Phenomenology · Physics 2009-10-31 T. M. Aliev , E. O. Iltan

Two loop electroweak corrections to b --> s gamma decays are computed. Fermion and photonic loop effects are found to reduce R = BR(b --> s gamma)/BR(b --> c e nu) by 8+-2% and lead to the standard model prediction BR(B --> X_s gamma)=(3.28…

High Energy Physics - Phenomenology · Physics 2009-10-31 Andrzej Czarnecki , William J. Marciano

We obtain the leading divergences at two-loop order for the decays $K_{S} \to \gamma \gamma$ and $K_{S} \to \gamma~\l^+ \l^-$ using only one-loop diagrams. We then find the double chiral logarithmic corrections to the decay branching ratio…

High Energy Physics - Phenomenology · Physics 2014-07-31 Karim Ghorbani

I present the Standard Model calculation of the decay rate for b -> s g (g denotes a gluon) at next-to-leading logarithms (NLL). In order to get a meaningful physical result, the decay b -> s g g and certain contributions of b -> s \bar{f}…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Liniger

We discuss the exclusive radiative B-meson decays B -> K* gamma and B -> rho gamma in a model-independent manner. The analysis is based on the heavy-quark limit of QCD. This allows a factorization of perturbatively calculable contributions…

High Energy Physics - Phenomenology · Physics 2009-11-07 Stefan W. Bosch

QCD corrections to $b \to s \gamma$ decay in the two Higgs doublet model are calculated from the energy scale of top quark to that of bottom. The constraints on the two Higgs doublet model from the new experimental bounds of $b\to s\gamma$…

High Energy Physics - Phenomenology · Physics 2007-05-23 Cai-Dian Lu

We first review the methods for determining gamma from B->D K decays that appeared after CKM 2008. We then discuss the theoretical errors in gamma extraction. The errors due to neglected D-Dbar and B_{d,s}-Bbar_{d,s} mixing can be avoided…

High Energy Physics - Phenomenology · Physics 2012-06-26 Jure Zupan

We propose moving all the $\gamma_{5}$ matrices to the rightmost position before continuing the dimension, and show that this simple prescription will enable the dimension regularization scheme proposed by 't Hooft and Veltman to be…

High Energy Physics - Theory · Physics 2011-02-01 Er-Cheng Tsai

We compute next-to-next-to-leading order corrections to the decay width difference of mass eigenstates and the charge-parity (CP) asymmetry $a_{\rm fs}$ in flavour-specific decays of neutral $B$ mesons. We include both current-current and…

High Energy Physics - Phenomenology · Physics 2026-04-01 Ulrich Nierste , Pascal Reeck , Vladyslav Shtabovenko , Matthias Steinhauser

An informal review is given of the status and direction of experiments on radiative B decays -- b -> s gamma and b -> d gamma. Branching fractions for exclusive and inclusive b -> s gamma decays, CP asymmetry limits, the photon energy…

High Energy Physics - Experiment · Physics 2007-05-23 Edward H. Thorndike

We study the region of small transverse momenta in qqbar- and gg-initiated processes with no colored particle detected in the final state. We present the universal expression of the O(alpha_s^2) logarithmically enhanced contributions up to…

High Energy Physics - Phenomenology · Physics 2009-10-31 D. de Florian , M. Grazzini

We apply Soft-Collinear Effective Theory to prove at leading power in Lambda_QCD/m_b a factorization formula for the radiative leptonic decay B -> gamma l nu. Large logarithms entering the hard-scattering kernel are systematically resummed…

High Energy Physics - Phenomenology · Physics 2011-09-13 Stefan W. Bosch

The photon polarization in B -> V gamma is a sensitive probe of right-handed currents. In the time dependent decay rate of B_s -> phi gamma the coefficients S and H in front of the sin(Delta m_s t) and the sinh(Delta Gamma_s /2 t) terms are…

High Energy Physics - Phenomenology · Physics 2008-11-26 Franz Muheim , Yuehong Xie , Roman Zwicky