Improved analysis of the (O_7, O_7) contribution to $\bar{B}\to X_s\gamma \gamma$ at $O({\alpha }_s)$

Abstract

The present study is devoted for an improved analysis of the self-interference contribution of the electromagnetic dipole operator O_7 to the double differential decay width $d\Gamma /(d{s}_{1}d{s}_2)$ for the inclusive $\bar{B}\to X_s\gamma \gamma$ process, where the kinematical variables s_1 and s_2 are defined as s_i=(p_b - q_i)^2/m_b^2 with p_b, q_1, q_2 being the momenta of the b-quark and two photons. This calculation completes the NLL QCD prediction of the numerically important self-interference contribution of O_7 by keeping the full dependence on the strange-quark mass m_s, which is introduced to control possible collinear configurations of one of the photons with the strange quark. Our results are given for exact m_s, in contrast to an earlier work where only logarithmic and constant terms in m_s were retained. This improved NLL result for the (O_7, O_7)-interference contribution shows that finite m_s effects are only sizable near the kinematical endpoints of the spectrum $d\Gamma /(d{s}_{1}d{s}_2)$. At the level of the branching ratio, in the phase-space region considered in this paper, it is observed that $Br[\bar{B}\to X_s\gamma \gamma ]$ does not develop a sizable m_s dependence: the impact on this branching ratio is less than 5% when m_s is varied between 400-600 MeV. For the same phase-space region finite strange quark mass effects for the branching ratio are less than 7%.

arXiv comment14 pages, 2 tables, 9 figures, extends earlier related works of us arXiv:1110.1251 and arXiv:1403.4502. A Fortran program "doublediff.F" giving the complete results of our work is also appended

References in corpus (39)

• Automatized One-Loop Calculations in 4 and D dimensions
• Cuba - a library for multidimensional numerical integration
• New Developments in FeynCalc 9.0
• Estimate of BR(B -> X_s gamma) at O(alpha_s^2)
• Weak Radiative B-Meson Decay Beyond Leading Logarithms
• Updated NNLO QCD predictions for the weak radiative B-meson decays
• Isolated photons in perturbative QCD
• Next-to-Leading QCD Corrections to B -> X_s gamma: Standard Model and Two-Higgs Doublet Model
• 2HDMs predictions for $B\to X_s\gamma$ in NLO QCD
• Effective Hamiltonian for Non-Leptonic |Delta F| = 1 Decays at NNLO in QCD
• SecDec-3.0: numerical evaluation of multi-scale integrals beyond one loop
• Two-loop mixing of dimension-five flavor-changing operators
• $\bar{B}\to X_s\gamma$ in the Two Higgs Doublet Model up to Next-to-Next-to-Leading Order in QCD
• High-precision calculation of multi-loop Feynman integrals by difference equations
• Addendum to: 2HDMs predictions for $B\to X_s\gamma$ in NLO QCD
• Three-Loop Mixing of Dipole Operators
• Four-Loop Anomalous Dimensions for Radiative Flavour-Changing Decays
• Radiative and Electroweak Penguin Decays of B Mesons
• QCD corrections to b -> s gamma gamma induced decays: B -> X_s gamma gamma and B_s -> gamma gamma
• The Double Radiative Decays $B\to \gamma \gamma$ in the Heavy Quark Limit
• QCD Corrections to $b\to s\gamma \gamma$ and Exclusive $B_s\to \gamma \gamma$ Decay
• B -> X_s gamma gamma and B_s -> gamma gamma in supersymmetry with broken R-parity
• Leading logarithmic QCD corrections to the B_s --> γγdecay rate including long-distance effects through B_s --> ϕγ--> γγ
• The $b\to s\gamma \gamma$ transition in softly broken supersymmetry
• The B -> X_s gamma gamma rare decay
• Tree-level contributions to B -> Xs gamma
• Leading logarithmic QCD corrections to the B_s --> γγdecays in the two Higgs doublet model
• The $B->X_{s}gammagamma$ decay in the standard model and the general two-Higgs-doublet model
• Phase space analysis for three and four massive particles in final states
• Predictions for $B\to K\gamma \gamma$ decays
• Technicolor corrections on $B_{s,d}\to \gamma \gamma$ decays in QCD factorization
• Tree-level contribution to \bar{B} -> X_d gamma using fragmentation functions
• Study of the Flavour Changing Neutral Current Decay mode $B\to K\gamma \gamma$
• The Belle II experiment: fundamental physics at the flavor frontier
• Spectator Effects in the Decay B -> K γγ
• NLL QCD contribution of the Electromagnetic Dipole operator to B-> X_s gamma gamma
• New Physics effects on decay $B_s\to \gamma \gamma$ in Technicolor Model
• NLL QCD contribution of the electromagnetic dipole operator to B -> X_s gamma gamma with a massive strange quark
• (O_8, O_8) contribution to $\bar{B}\to X_s\gamma \gamma$ at O(α_s)