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Related papers: Four-loop cusp anomalous dimension in QED

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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 show that the Quantum Spectral Curve (QSC) formalism, initially formulated for the spectrum of anomalous dimensions of all local single trace operators in N=4 SYM, can be extended to the generalized cusp anomalous dimension for all…

High Energy Physics - Theory · Physics 2016-05-03 Nikolay Gromov , Fedor Levkovich-Maslyuk

The anomalous dimension of the heavy-light quark current in HQET is calculated with three-loop accuracy, as well as the renormalized heavy-quark propagator. The NNL perturbative correction to f_B/f_D is obtained.

High Energy Physics - Phenomenology · Physics 2010-04-05 K. G. Chetyrkin , A. G. Grozin

We calculate the collinear anomalous dimensions in massless four-loop QCD and $\mathcal{N} = 4$ supersymmetric Yang-Mills theory from the infrared poles of vertex form factors. We give very precise numerical approximations and a conjecture…

High Energy Physics - Phenomenology · Physics 2021-07-14 Bakul Agarwal , Andreas von Manteuffel , Erik Panzer , Robert M. Schabinger

Three-loop counterterms for the Standard Model (SM) revealed that the matrix of anomalous dimensions ($\gamma$) of quarks is divergent in the $d \to 4$ limit unless a carefully chosen non-Hermitian square-root of $Z$ matrix is used in the…

High Energy Physics - Phenomenology · Physics 2021-10-04 Adrian Lewandowski

In this paper we evaluate the renormalization constants and anomalous dimensions for the squark wave function and mass within supersymmetric QCD. These results complement the ones obtained in Ref. \cite{Harlander:2009mn} and thus provide…

High Energy Physics - Phenomenology · Physics 2015-05-28 Thomas Hermann , Luminita Mihaila , Matthias Steinhauser

The velocity-dependent cusp anomalous dimension is by definition the ultraviolet (UV) anomalous dimension of a Wilson loop with a cusp. It appears in many physically interesting processes. In this talk we present recent progress in the…

High Energy Physics - Theory · Physics 2012-09-27 Johannes M. Henn

We compute the O(1/Nf^2) corrections to the flavour non-singlet quark bilinear currents in QCD in arbitrary spacetime dimensions. Hence, the anomalous dimension of the QED current $\bar{\psi} \sigma^{\mu\nu} \psi$ is deduced at four loops…

High Energy Physics - Phenomenology · Physics 2009-11-07 D. B. Ali , J. A. Gracey

The anomalous dimensions of four-quark operators $(\bar q_i q_j)_{V-A} (\bar q_k q_l)_{V-A}$ are calculated in the large $N_f$ limit. As expected, the result is a convergent series without renormalon ambiguities. Using the approximation of…

High Energy Physics - Phenomenology · Physics 2007-05-23 N. Pott

We present the planar four-loop anomalous dimension of the composite operator tr(phi[Z,phi]Z) in the flavour SU(2) sector of the N=4 SYM theory. At this loop order wrapping interactions are present: they give rise to contributions…

High Energy Physics - Theory · Physics 2008-11-26 F. Fiamberti , A. Santambrogio , C. Sieg , D. Zanon

I present results for soft anomalous dimensions in single top-quark production processes through three loops. I first discuss the cusp anomalous dimension with one massive and one massless line at three loops. I then calculate the…

High Energy Physics - Phenomenology · Physics 2019-05-01 Nikolaos Kidonakis

We consider the anomalous dimension $\gamma_{gg}^{(3)}(N)$ of the twist-two gluon operator of arbitrary Lorentz spin $N$ in the quark flavor singlet sector of a general gauge theory at four loops and construct its contribution proportional…

High Energy Physics - Phenomenology · Physics 2026-04-29 B. A. Kniehl , S. -O. Moch , V. N. Velizhanin , A. Vogt

The anomalous dimension $\gamma_m =1$ in the infrared region near conformal edge in the broken phase of the large $N_f$ QCD has been shown by the ladder Schwinger-Dyson equation and also by the lattice simulation for $N_f=8$ for $ N_c=3$.…

High Energy Physics - Phenomenology · Physics 2023-10-06 Koichi Yamawaki

We find that the anomalous dimension (in the $\bar{MS}$ scheme) of the chromo-magnetic operator $g_s\bar h_v\sigma_{\mu\nu} G^{\mu\nu} h_v$ in the heavy-quark effective theory is \gamma_{mag} = (C_A\alpha_s / 2\pi) [1 + ( 17/18 C_A - 13/18…

High Energy Physics - Phenomenology · Physics 2009-10-30 G. Amorós , M. Beneke , M. Neubert

We calculate the unpolarized and polarized three--loop anomalous dimensions and splitting functions $P_{\rm NS}^+, P_{\rm NS}^-$ and $P_{\rm NS}^{\rm s}$ in QCD in the $\overline{\sf MS}$ scheme by using the traditional method of…

High Energy Physics - Phenomenology · Physics 2021-09-15 J. Blümlein , P. Marquard , C. Schneider , K. Schönwald

We report a calculation in N = 4 Yang-Mills of the four-loop term g^4 in the collinear anomalous dimension g(lambda) which governs the universal subleading infrared structure of gluon scattering amplitudes. Using the method of obstructions…

High Energy Physics - Theory · Physics 2008-11-26 Freddy Cachazo , Marcus Spradlin , Anastasia Volovich

We review the computation of the anomalous dimension of twist operators in the planar limit of N=4 SYM using the asymptotic Bethe ansatz and demonstrate how this quantity is obtained at weak, strong and intermediate values of the coupling…

High Energy Physics - Theory · Physics 2015-05-20 Lisa Freyhult

We revisit the multi-loop structure of the anomalous-dimension matrix governing the infrared divergences of massless $n$-particle scattering amplitudes in non-abelian gauge theories. In particular, we derive its most general form at…

High Energy Physics - Phenomenology · Physics 2020-01-29 Thomas Becher , Matthias Neubert

We report first results of an ongoing project devoted to the analytical calculation of the QCD $\beta$-function and the quark mass anomalous dimension at the five loop level.

High Energy Physics - Phenomenology · Physics 2014-02-27 P. A. Baikov , K. G. Chetyrkin , J. H. Kühn

We use conformal symmetry to calculate the NNLO anomalous dimension matrix (three loops) for flavor-singlet axial-vector QCD operators for spin $N \le 8$ from a set of gauge-invariant two-point correlation functions. Combining this result…

High Energy Physics - Phenomenology · Physics 2025-10-20 V. M. Braun , K. G. Chetyrkin , A. N. Manashov