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Related papers: Results and Techniques of Multi-Loop Calculations

200 papers

In this contribution we provide further details to the recent calculation of QCD corrections to massive three-loop form factors presented in Ref. [1].

High Energy Physics - Phenomenology · Physics 2018-07-26 Roman N. Lee , Alexander V. Smirnov , Vladimir A. Smirnov , Matthias Steinhauser

We report on recent progress on five-loop calculations in perturbative QCD. We discuss the computation of the perturbative quark condensate, decoupling in QCD, and the precision determination of charm and bottom quark masses. For the…

High Energy Physics - Phenomenology · Physics 2024-07-24 Andreas Maier , Peter Marquard , York Schröder

We evaluate the three-loop corrections to the matching coefficient of the vector current between Quantum Chromodynamics (QCD) and non-relativistic QCD. The result is presented in the MSbar scheme where large perturbative corrections are…

High Energy Physics - Phenomenology · Physics 2014-03-05 Peter Marquard , Jan H. Piclum , Dirk Seidel , Matthias Steinhauser

We describe in detail the implementation of a systematic perturbative approach to observables in the QCD gradient-flow formalism. This includes a collection of all relevant Feynman rules of the five-dimensional field theory and the…

High Energy Physics - Lattice · Physics 2022-10-12 Johannes Artz , Robert V. Harlander , Fabian Lange , Tobias Neumann , Mario Prausa

In this paper we propose a method to compute the running top-Yukawa coupling in supersymmetric models with heavy mass spectrum based on the "running" and "decoupling" procedure. In order to enable this approach we compute the two-loop…

High Energy Physics - Phenomenology · Physics 2015-06-22 D. Kunz , L. Mihaila , N. Zerf

The lectures are a practical introduction to perturbative calculations in QED and QCD. I discuss methods of calculation of one- and two-loop diagrams in dimensional regularization, MSbar and on-shell renormalization schemes, decoupling of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrey Grozin

We investigate the effects of including the full three-loop QCD correction to the static short distance $1/r$ potential on the spectroscopy and decays in the charmonium and upsilon systems. We use a variational technique with the full…

High Energy Physics - Phenomenology · Physics 2013-08-28 Wayne W. Repko , Marco D. Santia , Stanley F. Radford

We compute three-loop corrections to the Higgs-gluon form factor, incorporating the top quark mass dependence. Our method is based on the combination of expansions around the top threshold and for large top quark mass, using conformal…

High Energy Physics - Phenomenology · Physics 2020-09-18 Joshua Davies , Ramona Groeber , Andreas Maier , Thomas Rauh , Matthias Steinhauser

The successive perturbative estimates of the pressure of QCD at high temperature T show no sign of convergence, unless the coupling constant g is unrealistically small. Exploiting known results of an effective field theory which separates…

High Energy Physics - Phenomenology · Physics 2009-11-10 J. -P. Blaizot , E. Iancu , A. Rebhan

We compute the two-loop electroweak correction to the production of the Higgs boson in gluon fusion to higher orders in the dimensional-regularization parameter $\epsilon = (d-4)/2$. We employ the method of differential equations to compute…

High Energy Physics - Phenomenology · Physics 2017-03-08 Marco Bonetti , Kirill Melnikov , Lorenzo Tancredi

Measurements of electroweak precision observables at future electron-positron colliders, such as the CEPC, FCC-ee, and ILC, will be sensitive to physics at multi-TeV scales. To achieve this sensitivity, precise predictions for the Standard…

High Energy Physics - Phenomenology · Physics 2021-04-07 Lisong Chen , Ayres Freitas

We extend in an extremely simple and straightforward way the well-known low-energy theorem for an effective Higgs-like scalar-gluon-gluon coupling [1] (as well as a similar one for for the effective coupling of the Higgs-like field to the…

High Energy Physics - Phenomenology · Physics 2026-02-10 Konstantin G. Chetyrkin

We present analytic results for three-loop fermionic corrections to the heavy-light form factors in perturbative quantum chromodynamics. Specifically, we present all light quark contributions and contributions from two heavy quark loops. We…

High Energy Physics - Phenomenology · Physics 2024-07-23 Sudeepan Datta , Narayan Rana

The 4-loop QED mass and wave function renormalization constants $Z_2$ and $Z_m$ have been evaluated in the on-shell subtraction scheme with 1100 digits of precision. We also worked out the coefficients of the five color structures of the…

High Energy Physics - Phenomenology · Physics 2020-03-05 Stefano Laporta

We obtain the two-loop QCD corrections to the Higgs plus three-parton amplitudes with dimension-seven operators in Higgs effective field theory. This provides the two-loop S-matrix elements for Higgs plus one-jet production at the LHC with…

High Energy Physics - Phenomenology · Physics 2020-03-18 Qingjun Jin , Gang Yang

We present the three-loop calculations of the nonrelativistic QCD (NRQCD) current renormalization constants and corresponding anomalous dimensions, and the matching coefficients for the spatial-temporal tensor and spatial-spatial…

High Energy Physics - Phenomenology · Physics 2023-10-19 Wei Tao , Zhen-Jun Xiao

We analytically compute the five-loop term in the beta function which governs the running of $\alpha_s$ --- the quark-gluon coupling constant in QCD. The new term leads to a reduction of the theory uncertainty in $\alpha_s$ taken at the…

High Energy Physics - Phenomenology · Physics 2017-03-01 P. A. Baikov , K. G. Chetyrkin , J. H. Kühn

We calculate the thermodynamic functions of a quark-gluon plasma for general N_c and N_f to three-loop order using hard-thermal-loop perturbation theory. At this order, all the ultraviolet divergences can be absorbed into renormalizations…

High Energy Physics - Phenomenology · Physics 2011-03-07 Jens O. Andersen , Lars E. Leganger , Michael Strickland , Nan Su

A Key feature of the minimal supersymmetric extension of the Standard Model (MSSM) is the existence of a light Higgs boson, the mass of which is not a free parameter but an observable that can be predicted from the theory. Given that the…

High Energy Physics - Phenomenology · Physics 2015-06-03 Philipp Kant

We propose to resum exactly any number of one-loop vacuum polarization insertions into the scale of the coupling of lowest order radiative corrections. This makes maximal use of the information contained in one-loop perturbative corrections…

High Energy Physics - Phenomenology · Physics 2010-11-01 P. Ball , M. Beneke , V. M Braun