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Related papers: Some Exact Results for Two-Loop Diagrams with Thre…

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We consider the two-loop massless propagator-type Feynman diagram with an arbitrary (non-integer) index on the central line. We analytically prove the equality of the two well-known results existing in the literature which express this…

High Energy Physics - Theory · Physics 2018-04-26 A. V. Kotikov , S. Teber

The massless sunrise diagram with an arbitrary number of loops is calculated in a simple but formal manner. The result is then verified by rigorous mathematical treatment. Pitfalls in the calculation with distributions are highlighted and…

High Energy Physics - Theory · Physics 2008-11-26 Andreas Aste

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

Three-loop vacuum integrals are an important building block for the calculation of a wide range of three-loop corrections. Until now, only results for integrals with one and two independent mass scales are known, but in the electroweak…

High Energy Physics - Phenomenology · Physics 2021-04-08 Ayres Freitas

The calculation of exclusive observables beyond the one-loop level requires elaborate techniques for the computation of multi-leg two-loop integrals. We discuss how the large number of different integrals appearing in actual two-loop…

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

As the new-generation precision experiments such as MOLLER and P2 look for physics beyond Standard Model, it is becoming increasingly important to evaluate the higher-order electroweak radiative corrections to a sub-percent level of…

High Energy Physics - Theory · Physics 2019-12-11 A. Aleksejevs , S. Barkanova

We extend the maximal-unitarity formalism at two loops to double-box integrals with four massive external legs. These are relevant for higher-point processes, as well as for heavy vector rescattering, VV -> VV. In this formalism, the…

High Energy Physics - Theory · Physics 2025-05-08 Henrik Johansson , David A. Kosower , Kasper J. Larsen

Conformal blocks for four point functions for fields with arbitrary spins in two dimensions are obtained by evaluating an appropriate integral. The results are just products of hypergeometric functions of the conformally invariant cross…

High Energy Physics - Theory · Physics 2015-06-05 H. Osborn

We calculate analytically the three-loop planar master integrals relevant for heavy-to-light form factors using the method of differential equations. After choosing a proper canonical basis, the boundary conditions are easy to be…

High Energy Physics - Phenomenology · Physics 2018-10-24 Long-Bin Chen , Jian Wang

An analytical approach is applied to the calculation of some dimensionally-regulated two-loop vertex diagrams with essential on-shell singularities. Such diagrams are important for the evaluation of QED corrections to the muon decay, QCD…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. I. Davydychev , V. A. Smirnov

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

A comprehensive study is performed of general massive, scalar, two-loop Feynman diagrams with three external legs. Algorithms for their numerical evaluation are introduced and discussed, numerical results are shown for all different…

High Energy Physics - Phenomenology · Physics 2009-11-10 A. Ferroglia , G. Passarino , M. Passera , S. Uccirati

This article is the first of a series of three presenting an alternative method to compute the one-loop scalar integrals. This novel method enjoys a couple of interesting features as compared with the method closely following 't Hooft and…

High Energy Physics - Phenomenology · Physics 2020-02-13 J. Ph. Guillet , E. Pilon , Y. Shimizu , M. S. Zidi

The scalar three-point function appearing in one-loop Feynman diagrams is compactly expressed in terms of a generalized hypergeometric function of two variables. Use is made of the connection between such Appell function and dilogarithms…

High Energy Physics - Phenomenology · Physics 2015-06-25 Luis G. Cabral-Rosetti , Miguel A. Sanchis-Lozano

In the recent years there has been an enormous development in the evaluation of higher order quantum corrections. An essential ingredient in the practical calculations is provided by vacuum diagrams, i.e. integrals without external momenta.…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Steinhauser

We introduce a new method for computing massless Feynman integrals analytically in parametric form. An analysis of the method yields a criterion for a primitive Feynman graph $G$ to evaluate to multiple zeta values. The criterion depends…

Algebraic Geometry · Mathematics 2009-03-24 Francis Brown

A comprehensive study is performed of general massive, tensor, two-loop Feynman diagrams with two and three external legs. Reduction to generalized scalar functions is discussed. Integral representations, supporting the same class of…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. Actis , A. Ferroglia , G. Passarino , M. Passera , S. Uccirati

The differential equation method is applied to evaluate analytically two-loop vertex Feynman diagrams. Three on-shell infrared divergent planar two-loop diagrams with zero thresholds contributing to the processes Z --> bb bar (for zero b…

High Energy Physics - Phenomenology · Physics 2009-10-30 J. Fleischer , A. V. Kotikov , O. L. Veretin

Direct hyperlogarithmic integration offers a strong alternative to differential equation methods for Feynman integration, particularly for multi-particle diagrams. We review a variety of results by the authors in which this method, employed…

A brief review of recent results on analytical evaluation of double-box Feynman integrals is presented. First steps towards evaluation of massless on-shell triple-box Feynman integrals within dimensional regularization are described. The…

High Energy Physics - Phenomenology · Physics 2009-11-07 V. A. Smirnov