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Related papers: Quark and gluon form factors in four-loop QCD

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We present an analytical calculation of the two-loop QCD corrections to the electromagnetic form factor of heavy quarks. The two-loop contributions to the form factor are reduced to linear combinations of master integrals, which are…

High Energy Physics - Phenomenology · Physics 2009-07-29 J. Gluza , A. Mitov , S. Moch , T. Riemann

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

We analytically compute the four-loop QCD corrections for the colour structure $(d_F^{abcd})^2$ to the massless non-singlet quark form factor. The computation involves non-trivial non-planar integral families which have master integrals in…

High Energy Physics - Phenomenology · Physics 2019-03-27 Roman N. Lee , Alexander V. Smirnov , Vladimir A. Smirnov , Matthias Steinhauser

We perform a perturbative QCD analysis of the gravitational form factors (GFFs) of nucleon at large momentum transfer. We derive the explicit factorization formula of the GFFs in terms of twist-3 and twist-4 light-cone distribution…

High Energy Physics - Phenomenology · Physics 2022-10-26 Xuan-Bo Tong , Jian-Ping Ma , Feng Yuan

The loop-induced processes gg -> h,H,A provide the dominant Higgs boson production mechanisms at the Tevatron and LHC in a large range of the minimal supersymmetric extension of the Standard Model. For squark masses below \sim 400 GeV…

High Energy Physics - Phenomenology · Physics 2008-11-26 Margarete Mühlleitner , Michael Spira

We consider the production of four charged leptons in hadron collisions and compute the next-to-leading order (NLO) QCD corrections to the loop-induced gluon fusion contribution by consistently accounting for the Higgs boson signal, its…

High Energy Physics - Phenomenology · Physics 2021-06-30 Massimiliano Grazzini , Stefan Kallweit , Marius Wiesemann , Jeong Yeon Yook

We compute the three-loop QCD corrections to the vertex function for the Yukawa coupling of a Higgs boson to a pair of bottom quarks in the limit of vanishing quark masses. This QCD form factor is a crucial ingredient to third-order QCD…

High Energy Physics - Phenomenology · Physics 2014-10-07 Thomas Gehrmann , Dominik Kara

The calculation of the next-to-leading order QCD corrections to the production of a neutral Higgs-boson pair is briefly summarized. The dominant production mechanism is gluon fusion via top-quark loops, so that the QCD corrections can be…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Dawson , S. Dittmaier , M. Spira

We compute the radiative corrections to the four-point amplitude $g+g \rightarrow A+A$ in massless Quantum Chromodynamics (QCD) up to order $a_s^4$ in perturbation theory. We used the effective field theory that describes the coupling of…

High Energy Physics - Phenomenology · Physics 2021-11-30 Arunima Bhattacharya , Maguni Mahakhud , Prakash Mathews , V. Ravindran

The calculation of massive three-loop QCD form factors using in particular the large moments method has been successfully applied to quarkonic contributions in [1]. We give a brief review of the different steps of the calculation and report…

High Energy Physics - Phenomenology · Physics 2024-08-14 J Blümlein , A. De Freitas , P. Marquard , C. Schneider

We study the soft and collinear (SV) contributions to inclusive Higgs-boson production in gluon-gluon fusion at four loops. Using recent progress for the quark and gluon form factors and Mellin moments of splitting functions, we are able to…

High Energy Physics - Phenomenology · Physics 2020-06-17 G. Das , S. Moch , A. Vogt

We compute the next-to-leading order virtual QCD corrections to Higgs pair production via gluon fusion. We present analytic results for the two-loop contributions to the spin-0 and spin-2 form factors in the amplitude. The reducible…

High Energy Physics - Phenomenology · Physics 2016-08-24 Giuseppe Degrassi , Pier Paolo Giardino , Ramona Gröber

We have computed the even-$N$ moments $N \leq 20$ of the gluon-to-quark splitting function $P_{\rm qg}$ at the fourth order of perturbative QCD via the renormalization of off-shell operator matrix elements. Our results, derived analytically…

High Energy Physics - Phenomenology · Physics 2024-04-16 G. Falcioni , F. Herzog , S. Moch , A. Vogt

We compute the color-planar and complete light quark non-singlet contributions to the heavy quark form factors in the case of the axialvector, scalar and pseudoscalar currents at three loops in perturbative QCD. We evaluate the master…

High Energy Physics - Phenomenology · Physics 2018-08-01 J. Ablinger , J. Blümlein , P. Marquard , N. Rana , C. Schneider

We study the electromagnetic on-shell form factor of quarks in massless perturbative QCD. We derive the complete pole part in dimensional regularization at three loops, and extend the resummation of the form factor to the…

High Energy Physics - Phenomenology · Physics 2009-11-11 S. Moch , J. A. M. Vermaseren , A. Vogt

We present all-order expressions for the leading double-logarithmic threshold contributions to the quark-gluon coefficient functions for inclusive Higgs-boson production in the heavy top-quark limit and for Drell-Yan lepton-pair production.…

High Energy Physics - Phenomenology · Physics 2015-06-22 N. A. Lo Presti , A. A. Almasy , A. Vogt

We present an analytic three-loop result for the leading color contribution to the Higgs-gluon form factor in QCD. The leading color contribution is given at next-to-next-to-leading order by the $N_c^2$-term in QCD with $N_c$ colors. The…

High Energy Physics - Phenomenology · Physics 2021-03-16 Mario Prausa , Johann Usovitsch

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 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

We present complete two-loop radiative corrections to the graviton-quark-antiquark form factor G^* \rightarrow q \overline q and graviton-gluon-gluon form factor G^* \rightarrow g g in SU(N) gauge theory with n_f light flavours using…

High Energy Physics - Phenomenology · Physics 2014-02-13 Daniel de Florian , Maguni Mahakhud , Prakash Mathews , Javier Mazzitelli , V. Ravindran