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We present the complete set of planar master integrals relevant to the calculation of three-point functions in four-loop massless Quantum Chromodynamics. Employing direct parametric integrations for a basis of finite integrals, we give…

High Energy Physics - Phenomenology · Physics 2019-07-22 Andreas von Manteuffel , Robert M. Schabinger

We present a computation of the one-loop QCD corrections to top-quark pair production in association with a $W$ boson, including terms up to order $\varepsilon^2$ in dimensional regularization. Providing a first glimpse into the complexity…

High Energy Physics - Phenomenology · Physics 2025-11-05 Matteo Becchetti , Maximilian Delto , Sara Ditsch , Philipp Alexander Kreer , Mattia Pozzoli , Lorenzo Tancredi

We calculate the gravitational form factors (GFFs) and pressure, shear and energy distributions for a quark state dressed with a gluon at one loop in QCD. We use the light-front Hamiltonian approach. In the light-front gauge, we use a…

High Energy Physics - Phenomenology · Physics 2022-04-06 Jai More , Asmita Mukherjee , Sreeraj Nair , Sudeep Saha

We complete the analytic evaluation of the master integrals for the two-loop non-planar box diagrams contributing to the top-pair production in the quark-initiated channel, at next-to-next-to-leading order in QCD. The integrals are…

High Energy Physics - Phenomenology · Physics 2022-10-12 Stefano Di Vita , Thomas Gehrmann , Stefano Laporta , Pierpaolo Mastrolia , Amedeo Primo , Ulrich Schubert

We present a calculation of the master integrals (MI's) required for the calculation of the Electroweak corrections to $gg\rightarrow \gamma\gamma$ production in which the process contains a light quark loop. The integrals can be broken…

High Energy Physics - Phenomenology · Physics 2024-03-29 Gabriele Fiore , Ciaran Williams

We calculate the form factors for the heavy-to-light transitions $B\rightarrow \pi,K $ by means of QCD sum rules using $\pi$ and $K$ light-cone wave functions. Higher twist contributions as well as gluonic corrections are taken into…

High Energy Physics - Phenomenology · Physics 2019-08-15 V. M. Belyaev , A. Khodjamirian , R. Rückl

We present in detail a calculation of the next-to-leading order QCD corrections to the process $e^+e^-\to 3$ jets with massive quarks. To isolate the soft and collinear divergencies of the four parton matrix elements, we modify the phase…

High Energy Physics - Phenomenology · Physics 2009-10-30 Arnd Brandenburg , Peter Uwer

Single scale Feynman integrals in quantum field theories obey difference or differential equations with respect to their discrete parameter $N$ or continuous parameter $x$. The analysis of these equations reveals to which order they…

High Energy Physics - Theory · Physics 2018-08-27 Johannes Blümlein

In the framework of analytic approach to QCD, which has been recently intensively developed, the dependence of nonperturbative contributions in a running coupling of strong interaction on initial perturbative approximation to 3-loop order…

High Energy Physics - Phenomenology · Physics 2007-05-23 Aleksey I. Alekseev

The infrared exponentiation properties of dimensionally-regularized multi-loop scattering amplitudes are typically hidden at the level of the integrand, materializing only after integral evaluation. We address this long-standing problem by…

High Energy Physics - Theory · Physics 2019-07-22 Robert M. Schabinger

We introduce a new computer algebra system optimized for use in lattice perturbation theory as well as continuum perturbation theory and a new framework to perform automated perturbative calculations on top of said computer algebra system.…

High Energy Physics - Lattice · Physics 2012-11-19 Christoph Lehner

We present a determination of a new class of Feynman diagrams relevant for second-order QCD corrections to the top quark decay t -> b W. Modern computing techniques allow us to perform a reduction of the original loop integrals to master…

High Energy Physics - Phenomenology · Physics 2017-08-23 Maciej Slusarczyk

We present methods for the numerical evaluation of the master integrals that appear in the calculation of scattering amplitudes at higher order in perturbative quantum field theory. We follow the general strategy of solving first-order…

High Energy Physics - Phenomenology · Physics 2025-01-06 Renato Maria Prisco , Jonathan Ronca , Francesco Tramontano

We review our perturbative techniques for improved heavy quark actions. A new procedure for computing improvement coefficients is suggested, where the continuum limit of a lattice-regularized theory provides the matching conditions.We also…

High Energy Physics - Lattice · Physics 2009-11-10 Matthew Nobes , Howard Trottier

We compute the ${\cal O}(\alpha_s^3)$ virtual QCD corrections to the $\gamma^*\to q\bar q g$ matrix element arising from the interference of the two-loop with the tree-level amplitude and from the self-interference of the one-loop…

High Energy Physics - Phenomenology · Physics 2010-04-06 L. W. Garland , T. Gehrmann , E. W. N. Glover , A. Koukoutsakis , E. Remiddi

In this note, we propose a factorization formula for gauge-theory scattering amplitudes up to two loops in the high-energy boosted limit. Our formula extends existing results in the literature by incorporating the contributions from massive…

High Energy Physics - Phenomenology · Physics 2023-12-20 Guoxing Wang , Tianya Xia , Li Lin Yang , Xiaoping Ye

We consider gluonic contributions to the heavy flavor Wilson coefficients at 3-loop order in QCD with two heavy quark lines in the asymptotic region $Q^2 \gg m_{1(2)}^2$. Here we report on the complete result in the case of two equal masses…

High Energy Physics - Phenomenology · Physics 2014-07-11 J. Ablinger , J. Blümlein , A. De Freitas , A. Hasselhuhn , A. von Manteuffel , M. Round , C. Schneider , F. Wißbrock

We present the analytic computation of the master integrals associated to certain two-loop non-planar topologies, which are needed to complete the evaluation of the last two color coefficients for the top-pair production in the…

High Energy Physics - Phenomenology · Physics 2019-12-13 Matteo Becchetti , Roberto Bonciani , Valerio Casconi , Andrea Ferroglia , Simone Lavacca , Andreas von Manteuffel

In this series of lectures, I shall begin with the current investigations on phenomenology of hadron dynamics to demonstrate the importance of solving hadronic bound states within the framework of light-front (LF) QCD. Then, I will describe…

High Energy Physics - Phenomenology · Physics 2007-05-23 Wei-Min Zhang

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