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Related papers: FeynCalc 10.2 and FeynHelpers 2: Multiloop calcula…

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We present algorithms to solve coupled systems of linear differential equations, arising in the calculation of massive Feynman diagrams with local operator insertions at 3-loop order, which do {\it not} request special choices of bases.…

Symbolic Computation · Computer Science 2016-01-11 Jakob Ablinger , Johannes Bluemlein , Abilio de Freitas , Carsten Schneider

A large class of Feynman integrals, like e.g., two-point parameter integrals with at most one mass and containing local operator insertions, can be transformed to multi-sums over hypergeometric expressions. In this survey article we present…

Symbolic Computation · Computer Science 2015-06-17 Carsten Schneider

With a key improvement, the auxiliary mass flow method is now able to compute Feynman integrals encountered in cutting-edge collider processes. We have successfully applied it to compute some integrals involved in two-loop electroweak…

High Energy Physics - Phenomenology · Physics 2022-03-16 Xiao Liu , Yan-Qing Ma

A purely numerical method, Direct ComputationMethod is applied to evaluate Feynman integrals. This method is based on the combination of an efficient numerical integration and an efficient extrapolation. In addition, high-precision…

High Energy Physics - Phenomenology · Physics 2014-11-18 F. Yuasa , T. Ishikawa , J. Fujimoto , N. Hamaguchi , E. de Doncker , Y. Shimizu

With an integrated software package {\tt GRACE}, it is possible to generate Feynman diagrams, calculate the total cross section and generate physics events automatically. We outline the hybrid method of parallel computation of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Fukuko Yuasa , Tadashi Ishikawa , Setsuya Kawabata , Denis Perret-Gallix , Kazuhiro Itakura , Yukihiko Hotta , Motoi Okuda

In this paper, we study systematically scalar one-loop two-, three-, and four-point Feynman integrals with complex internal masses. Our analytic results presented in this report are valid for both real and complex internal masses. The…

High Energy Physics - Phenomenology · Physics 2018-09-19 K. H. Phan , T. N. H. Pham

A Mathematica implementation of the program LERG-I is presented that performs the reduction of tensor integrals, encountered in one-loop Feynman diagram calculations, to scalar integrals. The program was originally coded in REDUCE and in…

High Energy Physics - Phenomenology · Physics 2009-10-28 Robin G. Stuart

A C-program DIANA (DIagram ANAlyser) for the automatic Feynman diagram evaluation is presented.

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Tentyukov , J. Fleischer

The method of differential equations has been proven to be a powerful tool for the computation of multi-loop Feynman integrals appearing in quantum field theory. It has been observed that in many instances a canonical basis can be chosen,…

High Energy Physics - Phenomenology · Physics 2017-05-23 Christoph Meyer

We calculate convergent 3-loop Feynman diagrams containing a single massive loop equipped with twist $\tau =2$ local operator insertions corresponding to spin $N$. They contribute to the massive operator matrix elements in QCD describing…

High Energy Physics - Phenomenology · Physics 2015-06-19 Jakob Ablinger , Johannes Blümlein , Clemens Raab , Carsten Schneider , Fabian Wißbrock

We briefly sketch the methods for a numerically stable evaluation of tensor one-loop integrals that have been used in the calculation of the complete electroweak one-loop corrections to $\Pep\Pem\to4 $fermions. In particular, the…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Denner , S. Dittmaier

By carefully analyzing the relations between operator methods and the discretized and continuum path integral formulations of quantum-mechanical systems, we have found the correct Feynman rules for one-dimensional path integrals in curved…

High Energy Physics - Theory · Physics 2009-10-28 Jan de Boer , Bas Peeters , Kostas Skenderis , Peter van Nieuwenhuizen

We present a program that implements the OPP reduction method to extract the coefficients of the one-loop scalar integrals from a user defined (sub)-amplitude or Feynman Diagram, as well as the rational terms coming from the 4-dimensional…

High Energy Physics - Phenomenology · Physics 2011-05-05 Giovanni Ossola , Costas G. Papadopoulos , Roberto Pittau

This note gives an update on recent developments in FeynArts, FormCalc, and LoopTools, and shows how the new features were used in making the latest version of FeynHiggs.

High Energy Physics - Phenomenology · Physics 2020-08-26 T. Hahn

We describe the implementation of the MSSM in the diagram generator FeynArts and the calculational tool FormCalc. This extension allows to perform loop calculations of MSSM processes almost fully automatically. The actual implementation has…

High Energy Physics - Phenomenology · Physics 2009-11-07 T. Hahn , C. Schappacher

Feynman integrals play a central role in the modern scattering amplitudes research program. Advancing our methods for evaluating Feynman integrals will, therefore, strengthen our ability to compare theoretical predictions with data from…

High Energy Physics - Theory · Physics 2024-01-03 Henrik J. Munch

New algebraic approach to analytical calculations of D-dimensional integrals for multi-loop Feynman diagrams is proposed. We show that the known analytical methods of evaluation of multi-loop Feynman integrals, such as integration by parts…

High Energy Physics - Theory · Physics 2010-04-05 A. P. Isaev

Feynman integral reduction by means of integration-by-parts identities is a major power gadget in a theorist toolbox indispensable for calculation of multiloop quantum effects relevant for particle phenomenology and formal theory alike. An…

High Energy Physics - Phenomenology · Physics 2024-02-13 A. V. Belitsky , A. A. Kokosinskaya , A. V. Smirnov , V. V. Voevodin , M. Zeng

We show how computational symbolic packages such as FeynArts and FormCalc can be adopted for the evaluation of one-loop hadronic electroweak radiative corrections for electron-nucleon scattering and applied to calculations of the nucleon…

Computational Physics · Physics 2009-02-18 A. Aleksejevs , S. Barkanova , P. G. Blunden

Collisions at the LHC produce many-particle final states, and for precise predictions the one-loop $N$-point corrections are needed. We study here the tensor reduction for Feynman integrals with $N \ge 6$. A general, recursive solution by…

High Energy Physics - Phenomenology · Physics 2015-06-03 J. Fleischer , T. Riemann