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We revisit the idea of numerically integrating the differential form of Feynman integrals. With a novel approach for the treatment of branch cuts, we develop an integrator capable of evaluating a basis of master integrals in double and…

High Energy Physics - Phenomenology · Physics 2026-03-06 Pau Petit Rosàs

We invent an automated method for computing the divergent part of Feynman integrals in dimensional regularization. Our method exploits simplifications from four-dimensional integration-by-parts identities. Leveraging algorithms from the…

High Energy Physics - Theory · Physics 2023-09-19 Johannes Henn , Rourou Ma , Kai Yan , Yang Zhang

Symbol letters are crucial for analytically calculating Feynman integrals in terms of iterated integrals. We present a novel method to construct the symbol letters for a given integral family without prior knowledge of the canonical…

High Energy Physics - Phenomenology · Physics 2025-06-13 Xuhang Jiang , Jiahao Liu , Xiaofeng Xu , Li Lin Yang

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

Negative dimensional integration is a step further dimensional regularization ideas. In this approach, based on the principle of analytic continuation, Feynman integrals are polynomial ones and for this reason very simple to handle,…

High Energy Physics - Theory · Physics 2009-10-30 Alfredo T. Suzuki , Alexandre G. M. Schmidt

We present a new method for numerically computing generic multi-loop Feynman integrals. The method relies on an iterative application of Feynman's trick for combining two propagators. Each application of Feynman's trick introduces a…

High Energy Physics - Phenomenology · Physics 2022-06-30 Martijn Hidding , Johann Usovitsch

A detailed investigation is presented of a set of algorithms which form the basis for a fast and reliable numerical integration of one-loop multi-leg (up to six) Feynman diagrams, with special attention to the behavior around (possibly)…

High Energy Physics - Phenomenology · Physics 2011-05-05 A. Ferroglia , G. Passarino , M. Passera , S. Uccirati

We evaluate analytically all previously unknown nonplanar master integrals for massless five-particle scattering at two loops, using the differential equations method. A canonical form of the differential equations is obtained by…

High Energy Physics - Phenomenology · Physics 2020-09-23 D. Chicherin , T. Gehrmann , J. M. Henn , P. Wasser , Y. Zhang , S. Zoia

At variance with fully inclusive quantities, which have been computed already at the two- or three-loop level, most exclusive observables are still known only at one-loop, as further progress was hampered so far by the greater computational…

High Energy Physics - Phenomenology · Physics 2009-10-31 T. Gehrmann , E. Remiddi

We elaborate on the method of differential equations for evaluating Feynman integrals. We focus on systems of equations for master integrals having a linear dependence on the dimensional parameter. For these systems we identify the criteria…

High Energy Physics - Phenomenology · Physics 2015-06-18 Mario Argeri , Stefano Di Vita , Pierpaolo Mastrolia , Edoardo Mirabella , Johannes Schlenk , Ulrich Schubert , Lorenzo Tancredi

Recently presented explicit formulae for asymptotic expansions of Feynman diagrams in the Sudakov limit are applied to typical two-loop diagrams. For a diagram with one non-zero mass these formulae provide an algorithm for analytical…

High Energy Physics - Phenomenology · Physics 2009-10-30 V. A. Smirnov

We calculate all three-loop, five-point, massless planar Feynman integral families in the dimensional regularization scheme. This is a new milestone in Feynman integral computations. The analysis covers four distinct families of Feynman…

High Energy Physics - Phenomenology · Physics 2025-12-22 Dmitry Chicherin , Yu Wu , Zihao Wu , Yongqun Xu , Shun-Qing Zhang , Yang Zhang

We construct a diagrammatic coaction acting on one-loop Feynman graphs and their cuts. The graphs are naturally identified with the corresponding (cut) Feynman integrals in dimensional regularization, whose coefficients of the Laurent…

High Energy Physics - Theory · Physics 2018-02-02 Samuel Abreu , Ruth Britto , Claude Duhr , Einan Gardi

The two-loop QCD corrections to vector boson pair production at hadron colliders involve a new class of Feynman integrals: two-loop four-point functions with two off-shell external legs. We describe their reduction to a small set of master…

High Energy Physics - Phenomenology · Physics 2013-08-26 Thomas Gehrmann , Lorenzo Tancredi , Erich Weihs

We review the method of the differential equations for the evaluation of multi-loop Feynman integrals. In particular, we focus on the series expansion approach for solving the system of differential equation and we discuss how to perform…

High Energy Physics - Phenomenology · Physics 2025-11-21 Tommaso Armadillo

A scheme for systematically achieving accurate numerical evaluation of multi-loop Feynman diagrams is developed. This shows the feasibility of a project aimed to produce a complete calculation for two-loop predictions in the Standard Model.…

High Energy Physics - Phenomenology · Physics 2008-11-26 G. Passarino

We present an algorithm to evaluate multiloop Feynman integrals with an arbitrary number of internal massive lines, with the masses being in general complex-valued, and its implementation in the \textsc{Mathematica} package…

High Energy Physics - Phenomenology · Physics 2022-10-24 Tommaso Armadillo , Roberto Bonciani , Simone Devoto , Narayan Rana , Alessandro Vicini

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

Applications of a method recently suggested by one of the authors (R.L.) are presented. This method is based on the use of dimensional recurrence relations and analytic properties of Feynman integrals as functions of the parameter of…

High Energy Physics - Phenomenology · Physics 2015-03-17 Roman N. Lee , Alexander V. Smirnov , Vladimir A. Smirnov

In this paper, we give a detailed account of the algorithm outlined in [1] for Feynman integral reduction and $\varepsilon$-factorised differential equations. The algorithm consists of two steps. In the first step, we use a new geometric…