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Related papers: GoSam: A program for automated one-loop Calculatio…

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We present an extension of the program golem95C for the numerical evaluation of scalar integrals and tensor form factors entering the calculation of one-loop amplitudes, which supports tensor ranks exceeding the number of propagators. This…

High Energy Physics - Phenomenology · Physics 2015-06-18 J. Ph. Guillet , G. Heinrich , J. F. von Soden-Fraunhofen

We discuss algebraic/numeric methods to compute one-loop corrections for multiparticle/jet production cross sections. By using efficient reduction algorithms a compact expression for the ggg\gamma\gamma -> 0 amplitude is obtained. Further a…

High Energy Physics - Phenomenology · Physics 2009-11-10 T. Binoth

We present a Mathematica package AmpRed for the semi-automatic calculations of multi-loop Feynman amplitudes with high efficiency and precision. AmpRed implements the methods of integration by parts and differential equations in the…

High Energy Physics - Phenomenology · Physics 2025-04-14 Wen Chen

Three programs are presented for automatically generating and calculating Feynman diagrams: the diagrams are generated with FeynArts, algebraically simplified with FormCalc, and finally evaluated numerically using the LoopTools package. The…

High Energy Physics - Phenomenology · Physics 2011-04-15 T. Hahn

We present a program for the numerical evaluation of scalar integrals and tensor form factors entering the calculation of one-loop amplitudes which supports the use of complex masses in the loop integrals. The program is built on an earlier…

High Energy Physics - Phenomenology · Physics 2015-05-27 G. Cullen , J. -Ph. Guillet , G. Heinrich , T. Kleinschmidt , E. Pilon , T. Reiter , M. Rodgers

In last decades, it has been realized that the next-to-leading order corrections may become very important, and sometimes requisite, for some processes involving quarkoinum production or decay, e.g., $e^+e^- \to J/\psi + \eta_c$ and $J/\psi…

High Energy Physics - Phenomenology · Physics 2015-06-16 Feng Feng

We present an improved version of our program package oneloop which -- written as a package for MAPLE -- solves one-loop Feynman integrals. The package is calculating one-, two- and three-point functions both algebraically and numerically…

High Energy Physics - Phenomenology · Physics 2009-10-30 L. Brücher , J. Franzkowski , D. Kreimer

A general formalism for computing only the rational parts of oneloop QCD amplitudes is developed. Starting from the Feynman integral representation of the one-loop amplitude, we use tensor reduction and recursive relations to compute the…

High Energy Physics - Phenomenology · Physics 2009-11-11 Zhi-Guang Xiao , Gang Yang , Chuan-Jie Zhu

In the very near future the first data from LHC will be available. The searches for the Higgs boson and for new physics will require precise predictions both for the signal and the background processes. Tree level calculations typically…

High Energy Physics - Phenomenology · Physics 2009-03-06 Thomas Reiter

We present a program for the numerical evaluation of form factors entering the calculation of one-loop amplitudes with up to six external legs. The program is written in Fortran95 and performs the reduction to a certain set of basis…

High Energy Physics - Phenomenology · Physics 2015-05-13 T. Binoth , J. -Ph. Guillet , G. Heinrich , E. Pilon , T. Reiter

We present a formalism for the calculation of multi-particle one-loop amplitudes, valid for an arbitrary number N of external legs, and for massive as well as massless particles. A new method for the tensor reduction is suggested which…

High Energy Physics - Phenomenology · Physics 2013-12-16 T. Binoth , J. Ph. Guillet , G. Heinrich , E. Pilon , C. Schubert

We present a novel set of Feynman rules and generalised unitarity cut-conditions for computing one-loop amplitudes via d-dimensional integrand reduction algorithm. Our algorithm is suited for analytic as well as numerical result, because…

High Energy Physics - Phenomenology · Physics 2015-05-25 W. J. Torres Bobadilla , A. R. Fazio , P. Mastrolia , E. Mirabella

Quantum corrections significantly influence the quantities observed in modern particle physics. The corresponding theoretical computations are usually quite lengthy which makes their automation mandatory. This review reports on the current…

High Energy Physics - Phenomenology · Physics 2011-08-17 R. Harlander , M. Steinhauser

Complete Feynman diagram automatic computation systems are now coming of age after many years of development. They are made available to the high energy physics community through user-friendly interfaces. Theorists and experimentalists can…

High Energy Physics - Phenomenology · Physics 2011-04-15 Denis Perrer-Gallix

The article deals with a number of the existings variants of direct calculation of amplitudes of processes with polarized Dirac particles. It is shown, that all of them are special cases of one and the same mathematical scheme. The…

High Energy Physics - Phenomenology · Physics 2007-05-23 Alexander L. Bondarev

We develop an algorithm of polynomial complexity for evaluating one-loop amplitudes with an arbitrary number of external particles. The algorithm is implemented in the Rocket program. Starting from particle vertices given by Feynman rules,…

High Energy Physics - Phenomenology · Physics 2009-05-05 W. T. Giele , G. Zanderighi

The program package XLOOPS calculates massive one- and two-loop Feynman diagrams. It consists of five parts: i) a graphical user interface ii) routines for generating diagrams from particle input iii) procedures for calculating one-loop…

High Energy Physics - Phenomenology · Physics 2011-02-11 L. Brücher , J. Franzkowski , A. Frink , D. Kreimer

A numerical program is presented which facilitates the computation of the full set of one-gluon loop diagrams (including ghost loop contributions), with M attached external gluon lines in all possible ways. The feasibility of such a task…

High Energy Physics - Theory · Physics 2007-05-23 A. S. Kapoyannis , A. I. Karanikas , C. N. Ktorides

The aim of XLOOPS is to calculate one-particle irreducible Feynman diagrams with one or two closed loops for arbitrary processes in the Standard model of particles and related theories. Up to now this aim is realized for all one-loop…

High Energy Physics - Phenomenology · Physics 2009-10-30 L. Brücher , J. Franzkowski , D. Kreimer

We present an algorithm for the numerical calculation of one-loop QCD amplitudes. The algorithm consists of subtraction terms, approximating the soft, collinear and ultraviolet divergences of one-loop amplitudes and a method to deform the…

High Energy Physics - Phenomenology · Physics 2010-12-09 Sebastian Becker , Christian Reuschle , Stefan Weinzierl