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Related papers: Four-loop results for the cusp anomalous dimension

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This talk presents details of the calculation of two-loop corrections to heavy baryon currents containing one heavy quark in leading order of the $1/m_Q$-expansion, i.e. in the limit of Heavy Quark Symmetry (HQS). The calculations lead to…

High Energy Physics - Phenomenology · Physics 2007-05-23 Stefan Groote

We review the four-loop QED corrections to the anomalous magnetic moment of the muon. The fermionic contributions with closed electron and tau contributions are discussed. Furthermore, we report on a new independent calculation of the…

High Energy Physics - Phenomenology · Physics 2017-09-21 Peter Marquard , Alexander V. Smirnov , Vladimir A. Smirnov , Matthias Steinhauser , David Wellmann

The QCD/HQET matching coefficient for the heavy-quark field is calculated up to four loops. It must be finite; this requirement produces analytical results for some terms in the four-loop on-shell heavy-quark field renormalization constant…

High Energy Physics - Phenomenology · Physics 2020-09-16 Andrey G. Grozin , Peter Marquard , Alexander V. Smirnov , Vladimir A. Smirnov , Matthias Steinhauser

We use the on-shell S-matrix and form factors to compute anomalous dimensions of higher dimension operators in the Standard Model Effective Field Theory. We find that in many instances, these computations are made simple by using the…

High Energy Physics - Phenomenology · Physics 2020-12-21 Joan Elias Miró , James Ingoldby , Marc Riembau

The anomalous dimensions of the general flavour non-singlet quark bilinear currents \psi \gamma^{[\mu_1} ... \gamma^{\mu_n]} \psi are computed at three loops in quantum chromodynamics in the minimal subtraction scheme. The dimension of the…

High Energy Physics - Phenomenology · Physics 2009-10-31 J. A. Gracey

The search for quartic anomalous gauge couplings (QAGC) at LEP requires appropriate predictions for the radiative processes e+ e- \to \nu\bar\nu \gamma\gamma, e+ e- \to q\bar{q}\gamma\gamma and e+ e- \to 4 fermions+\gamma. The current…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Osmo , F. Piccinini

We calculate the anomalous dimension of the cusped Wilson loop in ${\cal N}=4$ supersymmetric Yang-Mills theory to order $\lambda^2$ ($\lambda=g^2_{YM}N$). We show that the cancellation between the diagrams with the three-point vertex and…

High Energy Physics - Theory · Physics 2008-11-26 Yuri Makeenko , Poul Olesen , Gordon W. Semenoff

We study two-loop anomalous dimension matrices in QCD and related gauge theories for products of Wilson lines coupled at a point. We verify by an analysis in Euclidean space that the contributions to these matrices from diagrams that link…

High Energy Physics - Phenomenology · Physics 2009-06-19 Alexander Mitov , George Sterman , Ilmo Sung

We add the Wess-Zumino-Witten term to the N=3 massive nonlinear sigma model and study the leading logarithms in the anomalous sector. We obtain the leading logarithms to six loops for \pi^0 --> \gamma^*\gamma^* and to five loops for…

High Energy Physics - Phenomenology · Physics 2012-03-21 Johan Bijnens , Karol Kampf , Stefan Lanz

We study the first sub-leading correction $O((\ln s)^0)$ to the cusp anomalous dimension in the high spin expansion of finite twist operators in ${\cal N}=4$ SYM theory. This term is still governed by a linear integral equation which we…

High Energy Physics - Theory · Physics 2011-07-26 Davide Fioravanti , Paolo Grinza , Marco Rossi

We compute the general form of the six-loop anomalous dimension of twist-two operators with arbitrary spin in planar N=4 SYM theory. First we find the contribution from the asymptotic Bethe ansatz. Then we reconstruct the wrapping terms…

High Energy Physics - Theory · Physics 2015-06-09 Christian Marboe , Vitaly Velizhanin , Dmytro Volin

The search for quartic anomalous gauge couplings at LEP requires appropriate predictions for the radiative processes e+ e- \to \nu\bar\nu \gamma\gamma, e+ e- \to q\bar{q}\gamma\gamma and e+ e- \to 4 fermions+\gamma. Matrix elements are…

High Energy Physics - Phenomenology · Physics 2009-11-07 G. Montagna , M. Moretti , O. Nicrosini , M. Osmo , F. Piccinini

We derive two-loop anomalous dimensions for four-Fermi operators in supersymmetric theories using the effective Kahler potential. We introduce the general forms in generic gauge theories and apply our results to the flavor-changing…

High Energy Physics - Phenomenology · Physics 2017-07-13 Junji Hisano , Takumi Kuwahara , Yuji Omura , Takeki Sato

We numerically evaluate the two-loop QCD squared matrix element for in $q\bar{q}\to Z$ and $q\bar{q}\to Z\gamma$ with heavy top and bottom quarks circulating in a triangular fermion loop, by simultaneously subtracting infrared, ultraviolet,…

High Energy Physics - Phenomenology · Physics 2026-03-04 Dario Kermanschah , Matilde Vicini

We compute the complete $Q$-dependence of anomalous dimensions of traceless symmetric tensor operator $\phi^Q$ in $O(N)$ scalar theory to five-loop. The renormalization factors are extracted from $\phi^Q\rightarrow Q\phi$ form factors, and…

High Energy Physics - Theory · Physics 2022-08-30 Qingjun Jin , Yi Li

The anomalous magnetic moment of the muon is one of the most fundamental observables. It has been measured experimentally with a very high precision and on theory side the contributions from perturbative QED have been calculated up to…

High Energy Physics - Phenomenology · Physics 2014-02-06 P. A. Baikov , A. Maier , P. Marquard

We present new analytical five-loop Feynman-gauge results for the anomalous dimensions of ghost field and -vertex, generalizing the known values for SU(3) to a general gauge group. Together with previously published results on the quark…

High Energy Physics - Phenomenology · Physics 2017-04-05 Thomas Luthe , Andreas Maier , Peter Marquard , York Schroder

We have computed the fourth-order nf^2 contributions to all three non-singlet quark-quark splitting functions and their four nf^3 flavour-singlet counterparts for the evolution of the parton distributions of hadrons in perturbative QCD with…

High Energy Physics - Phenomenology · Physics 2017-02-01 J. Davies , A. Vogt , B. Ruijl , T. Ueda , J. A. M. Vermaseren

We present the result of a calculation for the first even moment of the non-singlet four-loop anomalous dimension of Wilson twist-2 operators in QCD with full color and flavor structures.

High Energy Physics - Phenomenology · Physics 2015-06-03 V. N. Velizhanin

The dimension-four genuine anomalous quartic couplings are studied in processes of six-fermion production via e+e- collisions. Complete tree-level electroweak calculations are performed including initial-state-radiation and beamstrahlung.…

High Energy Physics - Phenomenology · Physics 2007-05-23 Fabrizio Gangemi