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Related papers: Two-Loop Quark and Gluon Form Factors in Dimension…

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In this paper, we present one- and two-loop results for the renormalization of the gluon and quark gauge-invariant operators which appear in the definition of the QCD energy-momentum tensor, in dimensional regularization. To this end, we…

High Energy Physics - Lattice · Physics 2021-02-03 George Panagopoulos , Haralambos Panagopoulos , Gregoris Spanoudes

Low- and intermediate mass Higgs bosons decay preferably into fermion pairs. The one-loop electroweak corrections to the respective decay rates are dominated by a flavour-independent term of ${\cal O}(G_Fm_t^2)$. We calculate the two-loop…

High Energy Physics - Phenomenology · Physics 2009-10-28 Bernd A. Kniehl

Recently two-loop electroweak corrections to the neutral current four-fermion processes at high energies have been presented. The basic ingredient of this calculation is the evaluation of the two-loop corrections to the Abelian vector form…

High Energy Physics - Phenomenology · Physics 2009-01-07 Bernd Jantzen , Vladimir A. Smirnov

We present the results for heavy quark form factors at two-loop order in perturbative QCD for different currents, namely vector, axial-vector, scalar and pseudo-scalar currents, up to second order in the dimensional regularization…

High Energy Physics - Phenomenology · Physics 2018-05-09 J. Ablinger , A. Behring , J. Blümlein , G. Falcioni , A. De Freitas , P. Marquard , N. Rana , C. Schneider

Within a systematic approach based on the dimensionally regularized nonrelativistic quantum electrodynamics, we derive the complete result for the two-loop correction to order $(\alpha/\pi)^2 (Z \alpha)^4$ for the $g$ factor of an electron…

We present the electroweak corrections for the production of a photon pair through gluon fusion, focusing on the contribution from the first two generations of quarks. The two-loop amplitude is calculated using a series of projection…

High Energy Physics - Phenomenology · Physics 2025-12-09 Gabriele Fiore , Ciaran Williams

In these proceedings, we consider the factorizable contributions of the two-loop electroweak corrections to Higgs boson pair production at the Large Hadron Collider. We discuss the classification of factorizable diagrams and their…

High Energy Physics - Phenomenology · Physics 2024-07-09 Joshua Davies , Kay Schönwald , Matthias Steinhauser , Hantian Zhang

We calculate the two-loop corrections to heavy-quark pair production in the gluon fusion channel which arise from diagrams involving a closed light-quark loop. The calculation is carried out by keeping the exact dependence on the…

High Energy Physics - Phenomenology · Physics 2015-06-17 R. Bonciani , A. Ferroglia , T. Gehrmann , A. von Manteuffel , C. Studerus

Spin-2 fields are often candidates in physics beyond the Standard Model namely the models with extra-dimensions where spin-2 Kaluza-Klein gravitons couple to the fields of the SM. Also, in the context of Higgs searches, spin-2 fields have…

High Energy Physics - Phenomenology · Physics 2016-01-27 Taushif Ahmed , Goutam Das , Prakash Mathews , Narayan Rana , V. Ravindran

We compute the four-loop contributions to the photon quark and Higgs quark form factors involving two closed fermion loops. We present analytical results for all non-planar master integrals of the two non-planar integral families which…

High Energy Physics - Phenomenology · Physics 2017-07-19 Roman N. Lee , Alexander V. Smirnov , Vladimir A. Smirnov , Matthias Steinhauser

We consider the virtual corrections to Higgs boson pair production at next-to-next-to-leading order, in the large top quark mass limit. We compute five expansion terms for the box-type form factors and eight expansion terms for the triangle…

High Energy Physics - Phenomenology · Physics 2020-01-08 Joshua Davies , Matthias Steinhauser

We numerically compute the two-loop QCD corrections to $Z\gamma$ production at the LHC mediated by light- and heavy-quark box loops. The calculation employs the pipeline of refs. arXiv:2407.18051 and arXiv:2510.18801, which performs Monte…

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

The two-loop formfactor both for a U(1)xU(1) and a SU(2)xU(1) gauge theory with massive and massless gauge bosons respectively is evaluated at arbitrary momentum transfer q^2. The asymptotic behaviour for q^2->\infinity is compared to a…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Kotikov , J. H. Kuhn , O. Veretin

In all mass cases needed for quark and gluon self-energies, the two-loop master diagram is expanded at large and small $q^2$, in $d$ dimensions, using identities derived from integration by parts. Expansions are given, in terms of…

High Energy Physics - Phenomenology · Physics 2011-08-17 D. J. Broadhurst , J. Fleischer , O. V. Tarasov

Light quark masses can be determined through lattice simulations in regularization invariant momentum-subtraction(RI/MOM) schemes. Subsequently, matching factors, computed in continuum perturbation theory, are used in order to convert these…

High Energy Physics - Phenomenology · Physics 2011-05-04 Leandro G. Almeida , Christian Sturm

We compute the three-loop QCD corrections to the massive quark-anti-quark-photon form factors $F_1$ and $F_2$ in the large-$N_c$ limit. The analytic results are expressed in terms of Goncharov polylogarithms. This allows for a…

High Energy Physics - Phenomenology · Physics 2017-03-08 Johannes Henn , Alexander V. Smirnov , Vladimir A. Smirnov , Matthias Steinhauser

In this thesis, higher-order corrections to the perturbative expansions of scattering amplitudes involving the Higgs boson in the framework of Quantum Chromodynamics are evaluated, where we focus on processes that are mediated through…

High Energy Physics - Phenomenology · Physics 2019-08-28 Dominik Kara

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 calculate one-loop renormalization factors and mixing coefficients of bilinear quark operators for a class of gluon actions with six-link loops and O(a)-improved quark action. The calculation is carried out by evaluating on-shell Green's…

High Energy Physics - Lattice · Physics 2009-10-31 Sinya Aoki , Kei-ichi Nagai , Yusuke Taniguchi , Akira Ukawa

We compute the two-loop contributions to Higgs production via gluon-gluon fusion ($gg \to h$) and Higgs decay into two photons ($h \to \gamma\gamma$), arising from third-generation four-quark operators in the Standard Model effective field…

High Energy Physics - Phenomenology · Physics 2025-07-29 Ulrich Haisch , Marco Niggetiedt