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Related papers: Heavy-to-heavy quark decays at NNLO

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We present three-loop (NNNLO) corrections to the heavy-to-heavy quark transitions in the limit of equal initial and final quark masses. In analogy with the previously found NNLO corrections, the bulk of the result is due to the beta_0^2…

High Energy Physics - Phenomenology · Physics 2011-01-25 John Paul Archambault , Andrzej Czarnecki

Recently, $O(\alpha^3)$ corrections to the muon decay rate and $O(\alpha_s^3)$ to heavy quark decays have been determined by Fael, Sch\"onwald, and Steinhauser. This is the first such perturbative improvement of these important quantities…

High Energy Physics - Phenomenology · Physics 2021-09-13 Michał Czakon , Andrzej Czarnecki , Matthew Dowling

The decay width of b to c,c,c,l,nu has been computed as an expansion in limit (1- 3*(m_c/m_b)) << 1 with zero lepton invariant mass. Considering O(alpha_s^2) corrections to b to c,l,nu with zero invariant lepton mass, inclusion of our…

High Energy Physics - Phenomenology · Physics 2007-05-23 Matthew Dowling , Alexey Pak

We present a determination of a new class of three-loop Feynman diagrams describing heavy-to-light transitions. We apply it to find the O(alpha_s^2) corrections to the top quark decay t -> bW and to the distribution of lepton invariant mass…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ian Blokland , Andrzej Czarnecki , Maciej Slusarczyk , Fyodor Tkachov

We compute the O(\alpha_s^2) corrections to the differential rate of the semileptonic decay b -> clv at the "intermediate recoil" point, where the c-quark mass and the invariant mass of the leptons are equal. The calculation is based on an…

High Energy Physics - Phenomenology · Physics 2008-11-26 Matthew Dowling , Alexey Pak , Andrzej Czarnecki

The decay of B mesons can be predicted within the Heavy Quark Expansion as the decay of a free bottom quark plus corrections which are suppressed by powers of $1/m_b$. This contribution to Loops&Legs 2024 describes the calculation of the…

High Energy Physics - Phenomenology · Physics 2024-07-02 Manuel Egner

This paper presents $\alpha_s$ corrections to the inclusive semitauonic $B \to X_c \tau \bar{\nu}_\tau$ decay width and leptonic invariant mass spectrum up to order $1/m_b^3$ in the heavy quark expansion. Analytical results with full…

High Energy Physics - Phenomenology · Physics 2023-06-30 Daniel Moreno

We present complete O(alpha_s^2) corrections to the decay b-->c+l+nu at the point where the invariant mass of the leptons sqrt{q^2} equals the c quark mass. We use this result, together with previously obtained corrections at the ends of…

High Energy Physics - Phenomenology · Physics 2011-01-25 Andrzej Czarnecki , Kirill Melnikov

We present an analytic formula for the $O(\alpha_s)$ corrections to the decay $t\to H^+b$ for nonzero $m_H$ and $m_b$. The Equivalence Theorem is used to relate these corrections to those for the process $t\to W^+b$. Contrary to previously…

High Energy Physics - Phenomenology · Physics 2009-10-22 Andrzej Czarnecki , Sacha Davidson

Semileptonic and nonleptonic decays of the B_c meson are studied in the framework of the relativistic quark model. The heavy quark expansion in inverse powers of the heavy (b,c) quark mass is used to simplify calculations while the light…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Ebert , R. N. Faustov , V. O. Galkin

Recent progress in the calculation of multi-loop, multi-scale diagrams is reviewed. Expansion techniques combined with new developments in Computer algebra allow to evaluate the R ratio for massive quarks up to order $\alpha_s^2$ and,…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. H. Kuehn

We consider the resummation of large logarithmic corrections arising in the two-particle limit at next-to-next-to-leading logarithmic (NNLL) accuracy for the heavy-jet mass and $C$-parameter distributions in the decay of a Higgs boson to…

High Energy Physics - Phenomenology · Physics 2025-12-04 Elliot Fox , Aude Gehrmann-De Ridder , Thomas Gehrmann , Nigel Glover , Matteo Marcoli , Christian T. Preuss

B --> rho l nu decay is analyzed in the effective theory of heavy quark with infinite mass limit. The matrix element relevant to the heavy to light vector meson semileptonic decays is parametrized by a set of four heavy flavor-spin…

High Energy Physics - Phenomenology · Physics 2014-11-17 W. Y. Wang , Y. L. Wu

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 calculate the complete ${\cal O}(\alpha_s)$ corrections to the quark decay $b\to ccs$ taking full account of the quark masses, but neglecting penguin contributions. For a c to the b quark mass ratio $m_c/m_b= 0.3$ and a strange quark…

High Energy Physics - Phenomenology · Physics 2016-09-01 E. Bagan , Patricia Ball , B. Fiol , P. Gosdzinsky

Semileptonic decays of Lambda_b and Lambda_c baryons are studied within the Relativistic Three-Quark Model using finite heavy quark mass values. Employing the same parameters as have been used previously for the description of exclusive…

High Energy Physics - Phenomenology · Physics 2011-01-25 M. A. Ivanov , J. G. Korner , V. E. Lyubovitskij , A. G. Rusetsky

An analytic result for the O(alpha_s corrections to the triple differential B -> X_u l nu decay rate is presented, to leading order in the heavy-quark expansion. This is relevant for computing partially integrated decay distributions with…

High Energy Physics - Phenomenology · Physics 2015-06-25 F. De Fazio , M. Neubert

The results of perturbative QCD evaluation of the ~m_f^2/M_Z^2 contributions to the decay rates in Z--->bb and Z--->hadrons for the quark masses m_f << M_Z are presented. The recent results due to the combination of renormalization group…

High Energy Physics - Phenomenology · Physics 2009-10-28 Levan R. Surguladze

We present technical aspects of next-to-next-to-leading order calculations for heavy-to-light decays such as top quark decay, semileptonic b quark decay into a u quark, muon decay, and radiative decays like b -> s gamma. Algebraic reduction…

High Energy Physics - Phenomenology · Physics 2014-11-18 I. Blokland , A. Czarnecki , M. Slusarczyk , F. Tkachov

We present the two-loop master integrals relevant to the ${\mathcal O}(\alpha \alpha_s)$-corrections to the decay $H \rightarrow b \bar{b}$ through a $H t \bar{t}$-coupling. We keep the full dependence on the heavy particle masses, but…

High Energy Physics - Phenomenology · Physics 2019-06-26 Ekta Chaubey , Stefan Weinzierl
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