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Related papers: The three-loop unpolarized and polarized non-singl…

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The angle-dependent cusp anomalous dimension governs divergences coming from soft gluon exchanges between heavy particles, such as top quarks. We focus on the matter-dependent contributions and compute the first truly non-planar terms. They…

High Energy Physics - Theory · Physics 2021-01-20 Robin Brüser , Christoph Dlapa , Johannes M. Henn , Kai Yan

We study the collinear fragmentation of highly energetic jets defined with a small jet radius. In particular, we investigate how the corresponding fragmentation functions differ from their hadronic counterpart defined in the common…

High Energy Physics - Phenomenology · Physics 2024-10-10 Melissa van Beekveld , Mrinal Dasgupta , Basem Kamal El-Menoufi , Jack Helliwell , Alexander Karlberg , Pier Francesco Monni

We calculate the massless unpolarized Wilson coefficients for deeply inelastic scattering for the structure functions $F_2(x,Q^2), F_L(x,Q^2), x F_3(x,Q^2)$ in the $\overline{\sf MS}$ scheme and the polarized Wilson coefficients of the…

High Energy Physics - Phenomenology · Physics 2022-12-14 J. Blümlein , P. Marquard , C. Schneider , K. Schönwald

We have computed the next-to-next-to-leading-order (NNLO) contributions to the evolution of unpolarized parton distributions in perturbative QCD. In this talk, we briefly recall why this huge computation was necessary and outline how it was…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Vogt , S. Moch , J. Vermaseren

We have studied the recently completed analytic all-N expressions for the four-loop anomalous dimensions corresponding to the next-to-next-to-next-to-leading order splitting functions for the non-singlet quark distribution in perturbative…

High Energy Physics - Phenomenology · Physics 2026-05-06 S. Moch , A. Vogt

We compute the four-loop QCD corrections to the massless quark-anti-quark-photon form factor $F_q$ in the large-$N_c$ limit. From the pole part we extract analytic expressions for the corresponding cusp and collinear anomalous dimensions.

High Energy Physics - Phenomenology · Physics 2017-04-26 Johannes Henn , Roman N. Lee , Alexander V. Smirnov , Vladimir A. Smirnov , Matthias Steinhauser

We propose a closed expression for the three loop anomalous dimension of a class of twist-3 operators built with gauge fields and covariant derivatives. To this aim, we solve the long-range Bethe Ansatz equations at finite spin and provide…

High Energy Physics - Theory · Physics 2009-04-30 Matteo Beccaria

The anomalous dimensions of trilinear-quark operators are calculated at leading twist $t=3$ by diagonalizing the one-gluon exchange kernel of the renormalization-group type evolution equation for the nucleon distribution amplitude. This is…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Bergmann , W. Schroers , N. G. Stefanis

We report on the recent completion of the three-loop calculation of the soft anomalous dimension in massless gauge-theory scattering amplitudes. This brings the state-of-the-art knowledge of long-distance singularities in multi-leg QCD…

High Energy Physics - Phenomenology · Physics 2016-06-21 Einan Gardi , Øyvind Almelid , Claude Duhr

We review the computation of the anomalous dimensions of the twist-2 unpolarized operators in the large N_f expansion. Results are discussed for the predominantly gluonic singlet operator and the O(1/N_f) part of the 3-loop splitting…

High Energy Physics - Phenomenology · Physics 2007-05-23 JA Gracey

We present analytical five-loop results for the quark mass and quark field anomalous dimensions, for a general gauge group and in the MSbar scheme. We confirm the values known for the gauge group SU(3) from an independent calculation, and…

High Energy Physics - Phenomenology · Physics 2017-03-08 Thomas Luthe , Andreas Maier , Peter Marquard , York Schroder

We present the results of two-loop calculations of the anomalous dimension matrix for the Wilson twist-2 operators in the N=4 Supersymmetric Yang-Mills theory for polarized and unpolarized cases. This matrix can be transformed to a triangle…

High Energy Physics - Phenomenology · Physics 2009-11-10 A. V. Kotikov , L. N. Lipatov , V. N. Velizhanin

We perform a comprehensive perturbative study of the operator spectrum in multi-scalar theories with hypercubic global symmetry. This includes working out symmetry representations and their corresponding tensor structures. These structures…

High Energy Physics - Theory · Physics 2024-03-22 Alexander Bednyakov , Johan Henriksson , Stefanos R. Kousvos

We derive the complete set of two-loop anomalous dimensions describing the mixing of four-fermion operators in the Low Energy Effective Field Theory (LEFT). The calculation is performed in Naive Dimensional Regularization with anticommuting…

High Energy Physics - Phenomenology · Physics 2026-05-08 Jason Aebischer , Pol Morell , Marko Pesut , Javier Virto

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

Three--loop contributions to massive QED vacuum polarization are evaluated by a combination of analytical and numerical techniques. The first three Taylor coefficients, at small $q^2$, are obtained analytically, using $d$\/--dimensional…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. A. Baikov , D. J. Broadhurst

On-shell amplitude methods allow to derive one-loop renormalization effects from just tree-level amplitudes, with no need of loop calculations. We derive a simple formula to obtain the anomalous dimensions of higher-dimensional operators…

High Energy Physics - Phenomenology · Physics 2021-05-05 Pietro Baratella , Clara Fernandez , Alex Pomarol

We present the two-mass QCD contributions to the polarized pure singlet operator matrix element at three loop order in $x$-space. These terms are relevant for calculating the polarized structure function $g_1(x,Q^2)$ at $O(\alpha_s^3)$ as…

High Energy Physics - Phenomenology · Physics 2020-01-15 J. Ablinger , J. Blümlein , A. De Freitas , M. Saragnese , C. Schneider , K. Schönwald

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

We give an overview of recent developments in the computation of the anomalous dimension matrix of composite operators in non-forward kinematics. The elements of this matrix determine the scale dependence of non-perturbative parton…

High Energy Physics - Phenomenology · Physics 2024-05-29 S. Van Thurenhout