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Related papers: An easy way to solve two-loop vertex integrals

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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

In this work we calculate two two-loop massless Feynman integrals pertaining to self-energy diagrams using NDIM (Negative Dimensional Integration Method). We show that the answer we get is 36-fold degenerate. We then consider special cases…

High Energy Physics - Theory · Physics 2011-09-13 Alfredo T. Suzuki , Alexandre G. M. Schmidt

We apply negative dimensional integration method (NDIM) to three outstanding gauges: Feynman, light-cone and Coulomb gauges. Our aim is to show that NDIM is a very suitable technique to deal with loop integrals, being them originated from…

High Energy Physics - Theory · Physics 2014-11-18 Alfredo T. Suzuki , Alexandre G. M. Schmidt

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

An algorithm for calculating two-loop propagator type Feynman diagrams with arbitrary masses and external momentum is proposed. Recurrence relations allowing to express any scalar integral in terms of basic integrals are given. A minimal…

High Energy Physics - Phenomenology · Physics 2009-10-30 O. V. Tarasov

Negative dimensional integration method (NDIM) is revealing itself as a very useful technique for computing Feynman integrals, massless and/or massive, covariant and non-covariant alike. Up to now, however, the illustrative calculations…

High Energy Physics - Theory · Physics 2011-09-13 A. T. Suzuki , A. G. M. Schmidt

Dimensional regularization of Euclidean momentum space integrals is a highly successful technique in renormalization of quantum field theories. While it yields a straightforward algorithmic method, with which to evaluate diagrams beyond…

Mathematical Physics · Physics 2020-09-03 Juuso Österman

We present a new algorithm for the reduction of one-loop \emph{tensor} Feynman integrals with $n\leq 4$ external legs to \emph{scalar} Feynman integrals $I_n^D$ with $n=3,4$ legs in $D$ dimensions, where $D=d+2l$ with integer $l \geq 0$ and…

High Energy Physics - Phenomenology · Physics 2011-04-20 Jochem Fleischer , Tord Riemann

We present a method for rewriting dimensionally regulated Feynman parameter integrals in the Minkowski regime as a sum of real, positive integrands multiplied by complex prefactors. This representation eliminates the need for contour…

High Energy Physics - Phenomenology · Physics 2025-07-01 Stephen Jones , Anton Olsson , Thomas Stone

We present the integrand reduction via multivariate polynomial division as a natural technique to encode the unitarity conditions of Feynman amplitudes. We derive a recursive formula for the integrand reduction, valid for arbitrary…

High Energy Physics - Phenomenology · Physics 2015-06-16 P. Mastrolia , E. Mirabella , G. Ossola , T. Peraro

We set up a new, flexible approach for the tensor reduction of one-loop Feynman integrals. The 5-point tensor integrals up to rank R=5 are expressed by 4-point tensor integrals of rank R-1, such that the appearance of the inverse 5-point…

High Energy Physics - Phenomenology · Physics 2011-04-22 J. Fleischer , T. Riemann

A method of functional reduction for the dimensionally regularized one-loop Feynman integrals with massive propagators is described in detail. The method is based on a repeated application of the functional relations proposed by the author.…

High Energy Physics - Phenomenology · Physics 2022-07-13 O. V. Tarasov

A comprehensive study is performed of two-loop Feynman diagrams with three external legs which, due to the exchange of massless gauge-bosons, give raise to infrared and collinear divergencies. Their relevance in assembling realistic…

High Energy Physics - Phenomenology · Physics 2009-11-11 Giampiero Passarino , Sandro Uccirati

In this paper, we describe a numerical approach to evaluate Feynman loop integrals. In this approach the key technique is a combination of a numerical integration method and a numerical extrapolation method. Since the computation is carried…

High Energy Physics - Phenomenology · Physics 2011-09-21 F. Yuasa , T. Ishikawa , Y. Kurihara , J. Fujimoto , Y. Shimizu , N. Hamaguchi , E. de Doncker , K. Kato

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

By introducing an auxiliary parameter, we find a new representation for Feynman integrals, which defines a Feynman integral by analytical continuation of a series containing only vacuum integrals. The new representation therefore…

High Energy Physics - Phenomenology · Physics 2019-04-17 Xiao Liu , Yan-Qing Ma

The technique coined as NDIM - Negative Dimensional Integration Method by their discoverers, relies on a three-pronged basis: Gaussian integration, series expansion and analytic continuation. The technique has been successfully applied to…

Quantum Physics · Physics 2023-01-11 Alfredo Takashi Suzuki , Timothy Suzuki

An algorithm for the reduction of one-loop n-point tensor integrals to basic integrals is proposed. We transform tensor integrals to scalar integrals with shifted dimension and reduce these by recurrence relations to integrals in generic…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Fleischer , F. Jegerlehner , O. V. Tarasov

We evaluate the three-loop five-point pentagon-box-box massless integral family in the dimensional regularization scheme, via canonical differential equation. We use tools from computational algebraic geometry to enable the necessary…

High Energy Physics - Phenomenology · Physics 2025-01-15 Yuanche Liu , Antonela Matijašić , Julian Miczajka , Yingxuan Xu , Yongqun Xu , Yang Zhang

We elucidate the vector space (twisted relative cohomology) that is Poincar\'e dual to the vector space of Feynman integrals (twisted cohomology) in general spacetime dimension. The pairing between these spaces - an algebraic invariant…

High Energy Physics - Theory · Physics 2022-01-05 Simon Caron-Huot , Andrzej Pokraka