Updated Next-to-Next-to-Leading-Order QCD Predictions for the Weak Radiative $B$-Meson Decays

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Updated Next-to-Next-to-Leading-Order QCD Predictions for the Weak Radiative $B$ -Meson Decays

M. Misiak, H. M. Asatrian, R. Boughezal, M. Czakon, T. Ewerth, A. Ferroglia, P. Fiedler, P. Gambino, C. Greub, U. Haisch, T. Huber, M. Kamiński, G. Ossola, M. Poradziński, A. Rehman, T. Schutzmeier, M. Steinhauser, and J. Virto

Phys. Rev. Lett. 114, 221801 – Published 2 June 2015

Abstract

Weak radiative decays of the $B$ mesons belong to the most important flavor changing processes that provide constraints on physics at the TeV scale. In the derivation of such constraints, accurate standard model predictions for the inclusive branching ratios play a crucial role. In the current Letter we present an update of these predictions, incorporating all our results for the $O (α_{s}^{2})$ and lower-order perturbative corrections that have been calculated after 2006. New estimates of nonperturbative effects are taken into account, too. For the $C P$ - and isospin-averaged branching ratios, we find $B_{s γ} = (3.36 \pm 0.23) \times 10^{- 4}$ and $B_{d γ} = (1.7 3_{- 0.22}^{+ 0.12}) \times 10^{- 5}$ , for $E_{γ} > 1.6 GeV$ . Both results remain in agreement with the current experimental averages. Normalizing their sum to the inclusive semileptonic branching ratio, we obtain $R_{γ} \equiv (B_{s γ} + B_{d γ}) / B_{c ℓ ν} = (3.31 \pm 0.22) \times 10^{- 3}$ . A new bound from $B_{s γ}$ on the charged Higgs boson mass in the two-Higgs-doublet-model II reads $M_{H^{\pm}} > 480 GeV$ at 95% C.L.

Received 11 March 2015

DOI:https://doi.org/10.1103/PhysRevLett.114.221801

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Authors & Affiliations

M. Misiak¹, H. M. Asatrian², R. Boughezal³, M. Czakon⁴, T. Ewerth⁵, A. Ferroglia^6,7, P. Fiedler⁴, P. Gambino⁸, C. Greub⁹, U. Haisch^10,11, T. Huber¹², M. Kamiński¹, G. Ossola^6,7, M. Poradziński^1,12, A. Rehman¹, T. Schutzmeier¹³, M. Steinhauser⁵, and J. Virto¹²

¹Institute of Theoretical Physics, University of Warsaw, PL-02-093 Warsaw, Poland
²Yerevan Physics Institute, 0036 Yerevan, Armenia
³High Energy Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
⁴Institut für Theoretische Teilchenphysik und Kosmologie, RWTH Aachen University, D-52056 Aachen, Germany
⁵Institut für Theoretische Teilchenphysik, Karlsruhe Institute of Technology, D-76128 Karlsruhe, Germany
⁶New York City College of Technology, CUNY, Brooklyn, New York 11201, USA
⁷The Graduate School and University Center, CUNY, New York, New York 10016, USA
⁸Dipartimento di Fisica, Università di Torino & INFN, Torino, I-10125 Torino, Italy
⁹Albert Einstein Center for Fundamental Physics, Institute for Theoretical Physics, University of Bern, CH-3012 Bern, Switzerland
¹⁰Rudolf Peierls Centre for Theoretical Physics, University of Oxford, OX1 3PN Oxford, United Kingdom
¹¹CERN, Theory Division, CH-1211 Geneva 23, Switzerland
¹²Theoretische Physik 1, Naturwissenschaftlich-Technische Fakultät, Universität Siegen, D-57068 Siegen, Germany
¹³Physics Department, Florida State University, Tallahassee, Florida 32306-4350, USA