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Related papers: Three-loop QCD corrections to B_s -> mu^+ mu^-

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We discuss the QCD sum rule calculation of the heavy-quark effective theory parameters, $\lambda_E$ and $\lambda_H$, which correspond to matrix elements representing quark-gluon three-body components in the $B$-meson wavefunction. We derive…

High Energy Physics - Phenomenology · Physics 2013-12-16 Tetsuo Nishikawa , Kazuhiro Tanaka

A combination of algebraical and numerical techniques for calculating two-loop top-quark and Higgs-boson corrections to electroweak precision observables like $\Delta r$ or the $\rho$-parameter is presented. The renormalization is performed…

High Energy Physics - Phenomenology · Physics 2011-03-02 S. Bauberger , G. Weiglein

We compute the amplitudes for the two-body decay of $B$ mesons into longitudinally polarized light vector mesons at next-to-leading order in QCD. We give the explicit expressions in QCD factorization for all 34 transitions of a heavy-light…

High Energy Physics - Phenomenology · Physics 2008-10-02 Matthaeus Bartsch , Gerhard Buchalla , Christina Kraus

We compute the two-loop QCD corrections to the neutral Higgs-boson masses in the MSSM, including the effect of non-vanishing external momenta in the self-energies. We obtain corrections of O(alpha_t*alpha_s) and O(alpha*alpha_s), i.e., all…

High Energy Physics - Phenomenology · Physics 2015-06-23 G. Degrassi , S. Di Vita , P. Slavich

We complete the calculation of the QCD penguin amplitude at next-to-next-to-leading order in the QCD factorization approach to non-leptonic B-meson decays. This provides the last missing piece in the computation of the QCD correction to…

High Energy Physics - Phenomenology · Physics 2020-05-20 Guido Bell , Martin Beneke , Tobias Huber , Xin-Qiang Li

Analytic formulae are presented for the two-loop perturbative QCD corrections to b -> c decay at the zero recoil point, which are required for the extraction of |V_bc| from measurements of exclusive B -> D* l nu decays. The results are in…

High Energy Physics - Phenomenology · Physics 2011-01-25 J. Franzkowski , J. B. Tausk

We compute the 3-loop O(\alpha \alpha_s) correction to the Higgs boson production cross section arising from light quarks using an effective theory approach. Our calculation probes the factorization of QCD and electroweak perturbative…

High Energy Physics - Phenomenology · Physics 2010-01-15 Charalampos Anastasiou , Radja Boughezal , Frank Petriello

We present an analytic computation of the two-loop QCD corrections to $u\bar{d}\to W^+b\bar{b}$ for an on-shell $W$-boson using the leading colour and massless bottom quark approximations. We perform an integration-by-parts reduction of the…

High Energy Physics - Phenomenology · Physics 2021-10-14 Simon Badger , Heribertus Bayu Hartanto , Simone Zoia

Three important QCD-related aspects of the $\tau$ and $\mu$ dynamics are reviewed: the determination of the strong coupling from the hadronic tau decay width, leading to the updated value $\alpha_s(m_\tau^2) = 0.331 \pm 0.013$; the…

High Energy Physics - Phenomenology · Physics 2014-12-15 Antonio Pich

We provide a systematic treatment of the previously discovered power-enhanced QED corrections to the leptonic decay $B_q\to \mu^+\mu^-$ ($q = d, s$) in the framework of soft-collinear effective theory (SCET). Employing two-step matching on…

High Energy Physics - Phenomenology · Physics 2022-11-22 Martin Beneke , Christoph Bobeth , Robert Szafron

We compute the spin asymmetry of the muon decay through O(alpha^2) in perturbative QED. These two-loop corrections are about a factor five (twenty) smaller than the current statistical (systematic) uncertainty of the most precise…

High Energy Physics - Phenomenology · Physics 2014-09-10 Fabrizio Caola , Andrzej Czarnecki , Yi Liang , Kirill Melnikov , Robert Szafron

Chirally enhanced supersymmetric QCD corrections to FCNC processes are investigated in the framework of the MSSM with generic sources of flavor violation. These corrections arise from flavor-changing self-energy diagrams and can be absorbed…

High Energy Physics - Phenomenology · Physics 2015-03-13 Andreas Crivellin , Ulrich Nierste

We calculate one-loop renormalization factors of three-quark operators, which appear in the low energy effective Lagrangian of the nucleon decay, for $O(a)$-improved quark action and gauge action including six-link loops. This calculation…

High Energy Physics - Lattice · Physics 2016-12-28 S. Aoki , Y. Kuramashi , T. Onogi , N. Tsutsui

In this work we give a detailed description of a method for the calculation of QCD corrections to electroweak processes in dimensional regularization that does not require any definition of the gamma_5 matrix in d dimensions. This method…

High Energy Physics - Phenomenology · Physics 2009-10-28 Giancarlo Cella , Giuseppe Curci , Giulia Ricciardi , Andrea Vicere'

We consider the exclusive B_s -> phi mu+ mu- process in the standard model using a constituent quark loop model approach together with a simple parameterization of the quark dynamics. The model allows to compute the decay form factors and…

High Energy Physics - Phenomenology · Physics 2011-03-23 A. Deandrea , A. D. Polosa

We consider the QCD corrections to the electric dipole moment of the neutron in the Minimal Supersymmetric Standard Model. We provide a master formula for the Wilson coefficients at the low energy scale including for the first time the…

High Energy Physics - Phenomenology · Physics 2009-11-11 Giuseppe Degrassi , Enrico Franco , Schedar Marchetti , Luca Silvestrini

The theoretical status of NNLO QCD corrections to the inclusive radiative anti-B -> X_s gamma decay in the standard model is briefly overviewed. Emphasis is put on recent results for three-loop fermionic corrections to matrix elements of…

High Energy Physics - Phenomenology · Physics 2008-12-30 Thomas Schutzmeier

We extend previous computations of the second order QCD corrections to semileptonic b \to c inclusive transitions, to the case where the charged lepton in the final state is massive. This allows accurate description of b \to c \tau \bar…

High Energy Physics - Phenomenology · Physics 2010-03-03 Sandip Biswas , Kirill Melnikov

We calculate the two-loop QCD mixing of the dimension-five flavor-changing operators that arise in the Standard Model after integrating out the $W$, $Z$ and Higgs bosons and the top-quark, i.e.~the mixing among gluonic and photonic magnetic…

High Energy Physics - Phenomenology · Physics 2011-07-19 M. Misiak , M. Muenz

I evaluate the largest three-loop corrections to the mass of the lightest Higgs scalar boson in the Minimal Supersymmetric Standard Model in a mass-independent renormalization scheme, using effective field theory and renormalization group…

High Energy Physics - Phenomenology · Physics 2008-11-26 Stephen P. Martin