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Related papers: $B \to \gamma \gamma$ in an ACD model

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The short distance QCD corrections to $b\to s\gamma \gamma$ are calculated in the leading logarithmic approximation. The equivalence of operator basis reduction for S-matrix elements by using the equations of motion or by proving a low…

High Energy Physics - Phenomenology · Physics 2009-10-30 Chia-Hung V. Chang , Guey-Lin Lin , York-Peng Yao

We reinvestigate the leading QCD corrections to the radiative decay $b \to s \gamma for supersymmetric extensions of the Standard Model. Although the major contributions to the corrections originate from the running of the effective…

High Energy Physics - Phenomenology · Physics 2009-10-28 H. Anlauf

We evaluate the branching ratios of the radiative decays $B \to K^* \gamma $, and $B \to K_1 \gamma $ in the framework of three-point function QCD sum rules. We find: $ \Gamma(B \to K^* \gamma) / \Gamma(b \to s \gamma) = 0.17 \pm 0.05$ and…

High Energy Physics - Phenomenology · Physics 2009-10-22 P. Colangelo , C. A. Dominguez , G. Nardulli , N. Paver

We estimate the beyond the Standard Model (SM) contribution to the B_{s,d} \to \gamma\gamma double radiative decay in the framework of the model with one universal extra dimension. This contribution gives a \sim 3 (6)% enhancement of the…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. Devidze , A. Liparteliani , Ulf-G. Meißner

Working in a perturbative QCD model approach, we obtain the essential form factor of the radiative transition $B \rightarrow V^{*} \gamma$ and estimate the branching ratio $BR(B \rightarrow K^{*} \gamma)$. The results are determined by a…

High Energy Physics - Phenomenology · Physics 2009-10-28 Marina-Aura Dariescu , C. Dariescu

We analyze the double radiative B-meson decays B_s -> gamma gamma and B_d -> gamma gamma in QCD factorization based on the heavy-quark limit m_b >> Lambda_QCD. We systematically discuss the various contributions to these exclusive…

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

We give a more complete calculation of $b \to s\gamma $ decay, including leading log QCD corrections from $m_{top}$ to $M_W$ in addition to corrections from $M_{W}$ to $m_b$. We have included the full set of dimension-6 operators and…

High Energy Physics - Phenomenology · Physics 2009-10-28 Chong-Shong Gao , Jing-Liang Hu , Cai-Dian Lu , Zhao-Ming Qiu

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

We calculate the branching ratio of $\Lambda_b \to \Lambda \gamma$ in the standard model using the PQCD method. The predicted branching ratio $B(\Lambda_b \to \Lambda \gamma)$ is about $(4.3\sim 8.6)\times 10^{-8}$, with reasonable…

High Energy Physics - Phenomenology · Physics 2009-11-11 Xiao-Gang He , Tong Li , Xue-Qian Li , Yu-Ming Wang

We present a complete calculation of the Leading Order QCD corrections to the quark level decay amplitude for b -> s gamma gamma and study their relevance for both the inclusive branching ratio BR(B -> X_s gamma gamma) and for the exclusive…

High Energy Physics - Phenomenology · Physics 2014-11-17 Laura Reina , Giulia Ricciardi , Amarjit Soni

The radiative decays $ B^{*} (D^{*})\to B(D) \gamma$ are investigated in the framework of light cone QCD sum rules. The transition amplitude and decay rates are estimated.It is shown that our results on branching ratios of D meson decays…

High Energy Physics - Phenomenology · Physics 2015-06-25 T. M. Aliev , D. A. Demir , E. Iltan , N. K. Pak

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

The complete calculation of the lowest order short-distance contributions to the $B_{s}\to\gamma\gamma$ decay in the SM are presented. The amplitude and branching ratio are calculated.

High Energy Physics - Phenomenology · Physics 2007-05-23 Gela G. Devidze

We present leading logarithmic QCD corrections to the decay B_s --> \gamma\gamma in the Standard Model. Further, the form factor F_{1}(0) of B_s --> \phi\gamma is calculated in the framework of QCD sum rules and found to be in agreement…

High Energy Physics - Phenomenology · Physics 2009-10-30 G. Hiller , E. O. Iltan

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…

The radiative decays $ B^{*} (D^{*})\rightarrow B(D) \gamma$ are investigated in the framework of light cone QCD sum rules. The transition amplitude and decay rates are estimated.It is shown that our results on branching ratios of D meson…

High Energy Physics - Phenomenology · Physics 2009-10-28 T. M. Aliev , D. A. Demir , E. Iltan , N. K. Pak

The calculation of QCD corrections to the width difference Delta Gamma in the B_s meson system is presented. The next-to-leading order corrections reduce the dependence on the renormalization scale significantly and allow for a meaningful…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ulrich Nierste

We study the effect of supersymmetric contributions to the effective quark transition $b\to s\gamma\gamma$, including leading order QCD effects. We apply the discussion to the decay $B_s\to\gamma\gamma$. Even though one-particle irreducible…

High Energy Physics - Phenomenology · Physics 2009-10-30 S. Bertolini , J. Matias

The calculation of the one-loop induced decay rate b -> s \gamma is improved by including radiative corrections to the charged Higgs mass and to the charged-Higgs-fermion-fermion vertex. It is shown how the radiative corrections modify the…

High Energy Physics - Phenomenology · Physics 2009-10-22 Marco A. Diaz

We find some errors in previous calculation of leading log QCD corrections to $b \to s\gamma $ decay, which include corrections from $m_{top}$ to $M_W$ in addition to corrections from $M_{W}$ to $m_b$. The inclusive decay rate is found to…

High Energy Physics - Phenomenology · Physics 2016-08-14 Cai-Dian Lü , Jing-Liang Hu , Chong-Shou Gao
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