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Related papers: Numerical Multi-Loop Calculations via Finite Integ…

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We construct the complete (planar and non-planar) integrand for the six-loop four-point amplitude in maximal $D\le10$ super-Yang-Mills. This construction employs new advances that combat the proliferation of diagram contributions and state…

High Energy Physics - Theory · Physics 2021-12-13 John Joseph M. Carrasco , Alex Edison , Henrik Johansson

An approach for an effective computer evaluation of one-loop multi-leg diagrams is proposed. It's main feature is the combined use of several systems - DIANA, FORM and MAPLE. As an application we consider the one-loop correction to Higgs…

High Energy Physics - Phenomenology · Physics 2009-11-07 F. Jegerlehner , O. Tarasov

A method for the evaluation of the epsilon expansion of multi-loop massless Feynman integrals is introduced. This method is based on the Gegenbauer polynomial technique and the expansion of the Gamma function in terms of harmonic sums.…

High Energy Physics - Phenomenology · Physics 2007-05-23 Stefan Bekavac

In modern quantum field theory, one of the most important tasks is the calculation of loop integrals. Loop integrals appear when evaluating the Feynman diagrams with one or more loops by integrating over the internal momenta. Even though…

High Energy Physics - Theory · Physics 2020-06-24 Maxim Bezuglov

SecDec is a program which can be used for the factorization of dimensionally regulated poles from parametric integrals, in particular multi-loop integrals, and the subsequent numerical evaluation of the finite coefficients. Here we present…

High Energy Physics - Phenomenology · Physics 2015-09-22 S. Borowka , G. Heinrich , S. P. Jones , M. Kerner , J. Schlenk , T. Zirke

We report on a program for the numerical evaluation of divergent multi-loop integrals. The program is based on iterated sector decomposition. We improve the original algorithm of Binoth and Heinrich such that the program is guaranteed to…

High Energy Physics - Phenomenology · Physics 2008-11-26 Christian Bogner , Stefan Weinzierl

The computational technique of $N$-fold Mellin-Barnes (MB) integrals, presented in a companion paper by the same authors, is used to derive sets of series representations of the massive one-loop conformal 3-point Feynman integral in various…

High Energy Physics - Theory · Physics 2021-05-19 B. Ananthanarayan , Sumit Banik , Samuel Friot , Shayan Ghosh

Based on the method in Refs.~{\tt [D.~Kreimer, Z.\ Phys.\ C {\bf 54} (1992) 667} and {\tt Int.\ J.\ Mod.\ Phys.\ A {\bf 8} (1993) 1797]}, we present analytic results for scalar one-loop four-point Feynman integrals with complex internal…

High Energy Physics - Phenomenology · Physics 2019-12-06 K. H. Phan

A method for calculating the $1/d$ expansion coefficients for solutions of integration by parts relations for Feynman integrals is presented. The idea is to use linear substitutions to transform these relations to an explicitly recursive…

High Energy Physics - Phenomenology · Physics 2026-01-21 P. A. Baikov

We introduce techniques to treat numerically Mellin-Barnes integrals in physical regions, which arise in the need of the computation of Feynman integrals for the electroweak two-loop corrections to the pseudo observables at the Z-boson…

High Energy Physics - Phenomenology · Physics 2018-10-11 Johann Usovitsch , Ievgen Dubovyk , Tord Riemann

Higher-order radiative corrections play an important role in precision studies of the electroweak and Higgs sector, as well as for the detailed understanding of large backgrounds to new physics searches. For corrections beyond the one-loop…

High Energy Physics - Phenomenology · Physics 2016-08-16 Ayres Freitas

We provide analytic results for two-loop four-point master integrals with one massive propagator and one massive leg relevant to single top production. Canonical bases of master integrals are constructed and the Simplified Differential…

High Energy Physics - Phenomenology · Physics 2023-05-31 Nikolaos Syrrakos

We present some techniques which have been developed recently or in the recent past to compute Feynman graphs beyond one-loop order. These techniques are useful to compute the three-loop splitting functions in QCD and to obtain the complete…

High Energy Physics - Phenomenology · Physics 2015-06-25 W. L. van Neerven

Finite-temperature quantum field theory provides the foundation for many important phenomena in the Standard Model and extensions, including phase transitions, baryogenesis, and gravitational waves. Methods are developed to enable…

High Energy Physics - Phenomenology · Physics 2024-01-11 D. Harnett , Siyuan Li , T. G. Steele

Higher order corrections in perturbative quantum field theory are required for precise theoretical analysis to investigate new physics beyond the Standard Model. This indicates that we need to evaluate Feynman loop diagram with multi-loop…

High Energy Physics - Phenomenology · Physics 2014-12-02 Shinji Motoki , Hiroshi Daisaka , Naohito Nakasato , Tadashi Ishikawa , Fukuko Yuasa , Toshiyuki Fukushige , Atsushi Kawai , Junichiro Makino

The program FIESTA has been completely rewritten. Now it can be used not only as a tool to evaluate Feynman integrals numerically, but also to expand Feynman integrals automatically in limits of momenta and masses with the use of sector…

High Energy Physics - Phenomenology · Physics 2011-01-17 A. V. Smirnov , V. A. Smirnov , M. Tentyukov

The version 2.0 of the program SecDec is described, which can be used for the extraction of poles within dimensional regularisation from multi-loop integrals as well as phase space integrals. The numerical evaluation of the resulting finite…

High Energy Physics - Phenomenology · Physics 2012-06-25 Sophia Borowka , Jonathon Carter , Gudrun Heinrich

SecDec is a program which can be used for the factorisation of poles and subsequent numerical evaluation of multi-loop integrals, in particular massive two-loop integrals. We show applications to two-loop master integrals entering the…

High Energy Physics - Phenomenology · Physics 2013-11-27 Sophia Borowka , Gudrun Heinrich

We provide high-energy approximations for all one-loop scalar 3- and 4-point functions and the corresponding tensor integrals that appear in scattering processes with four external on-shell particles. Our expressions are valid if all…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Roth , A. Denner

The calculation of the two-loop corrections to the three jet production rate and to event shapes in electron-positron annihilation requires the computation of a number of up to now unknown two-loop four-point master integrals with one…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. Gehrmann , E. Remiddi