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Related papers: Scalar one-loop Feynman integrals with complex int…

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We propose a novel method, called the dimension-changing transformation (DCT), to compute one-loop Feynman integrals and recently introduced fixed-branch integrals to arbitrary orders in $\epsilon$. The DCT relates one-loop Feynman…

High Energy Physics - Phenomenology · Physics 2024-12-31 Rui-Jun Huang , Dong-Shan Jian , Yan-Qing Ma , Dao-Ming Mu , Wen-Hao Wu

The calculation of hard scattering amplitudes up to NLO is automated in numerical tools, such as OpenLoops. The LHC and future experiments, however, demand high-precision predictions at NNLO and beyond for a wide range of particle…

High Energy Physics - Phenomenology · Physics 2024-12-20 Natalie Schär , Max F. Zoller

We calculate analytically the two-loop triangle integrals entering the $\mathcal{O}(\alpha\alpha_s)$ corrections to the $HZV$ vertex with $V=Z^*,\gamma^*$ using the method of differential equations. Our result provides a prototype to study…

High Energy Physics - Phenomenology · Physics 2019-10-23 Yuxuan Wang , Xiaofeng Xu , Li Lin Yang

We present FaRe, a package for Mathematica that implements the decomposition of a generic tensor Feynman integral, with arbitrary loop number, into scalar integrals in higher dimension. In order for FaRe to work, the package FeynCalc is…

High Energy Physics - Phenomenology · Physics 2016-03-23 Michele Re Fiorentin

In these lectures I will give an introduction to Feynman integrals. In the first part of the course I review the basics of the perturbative expansion in quantum field theories. In the second part of the course I will discuss more advanced…

High Energy Physics - Phenomenology · Physics 2010-05-12 Stefan Weinzierl

We review in a pedagogical way the method of differential equations for the evaluation of D-dimensionally regulated Feynman integrals. After dealing with the general features of the technique, we discuss its application in the context of…

High Energy Physics - Phenomenology · Physics 2008-11-26 Mario Argeri , Pierpaolo Mastrolia

We give a complete analytical computation of three-point one-loop integrals with one heavy propagator, up to the third tensor rank, for arbitrary values of external momenta and masses.

High Energy Physics - Phenomenology · Physics 2008-11-26 Antonio O. Bouzas , Ruben Flores-Mendieta

We describe in some detail the present features of an automatic loop calculation program as well as the integration techniques that go into it. The program, called XLOOPS 1.0, allows one to calculate massive one- and two-loop Feynman…

High Energy Physics - Phenomenology · Physics 2009-09-25 A. Frink , J. G. Körner , J. B. Tausk

A numerical program is presented which facilitates a computation pertaining to 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…

High Energy Physics - Theory · Physics 2009-11-11 A. S. Kapoyannis , A. I. Karanikas , C. N. Ktorides

In this talk, we review a loop-by-loop approach used to generate differential equations for multi-scale (dual) Feynman integrals. We illustrate the method on a well-established example: the unequal mass elliptic sunrise.

High Energy Physics - Theory · Physics 2023-09-12 Mathieu Giroux , Andrzej Pokraka , Franziska Porkert , Yoann Sohnle

Recently in arXiv:2012.05599 Rudenko presented a formula for the volume of hyperbolic orthoschemes in terms of alternating polylogarithms. We use this result to provide an explicit analytic result for the one-loop scalar n-gon Feynman…

High Energy Physics - Theory · Physics 2024-04-15 Lecheng Ren , Marcus Spradlin , Cristian Vergu , Anastasia Volovich

Over the last year significant progress was made in the understanding of the computation of Feynman integrals using differential equations. These lectures give a review of these developments, while not assuming any prior knowledge of the…

High Energy Physics - Phenomenology · Physics 2015-06-23 Johannes M. Henn

We introduce a novel structure for Feynman integrals, reformulating them as integrals over a small set of parameters with a fully controllable integrand. The integrand closely resembles one-loop Feynman integrals, and they are very easy to…

High Energy Physics - Phenomenology · Physics 2024-12-31 Li-Hong Huang , Rui-Jun Huang , Yan-Qing Ma

We present a generally applicable reduction formalism which makes it possible to express an arbitrary tensor and scalar one-loop Feynman integral, with N external lines and massless propagators, in terms of a basic set of eight fundamental…

High Energy Physics - Phenomenology · Physics 2007-05-23 G. Duplancic , B. Nizic

Feynman integrals obey linear relations governed by intersection numbers, which act as scalar products between vector spaces. We present a general algorithm for constructing multivariate intersection numbers relevant to Feynman integrals,…

High Energy Physics - Theory · Physics 2019-11-20 Hjalte Frellesvig , Federico Gasparotto , Manoj K. Mandal , Pierpaolo Mastrolia , Luca Mattiazzi , Sebastian Mizera

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

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

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

This work investigates in detail the performance and advantages of a new quantum Monte Carlo integrator, dubbed Quantum Fourier Iterative Amplitude Estimation (QFIAE), to numerically evaluate for the first time loop Feynman integrals in a…

High Energy Physics - Phenomenology · Physics 2024-11-20 Jorge J. Martínez de Lejarza , Leandro Cieri , Michele Grossi , Sofia Vallecorsa , Germán Rodrigo

It was observed that hyperlogarithms provide a tool to carry out Feynman integrals. So far, this method has been applied successfully to finite single-scale processes. However, it can be employed in more general situations. We give examples…

High Energy Physics - Theory · Physics 2014-04-01 Erik Panzer