English
Related papers

Related papers: A new method for one-loop amplitude generation and…

200 papers

In this presentation we review the current status in the automated evaluation of scattering amplitudes, with particular attention to the developments related with NLO calculations, which led to the construction of powerful multi-purpose…

High Energy Physics - Phenomenology · Physics 2015-08-11 Giovanni Ossola

We present an alternative reduction to master integrals for one-loop amplitudes using a unitarity cut method in arbitrary dimensions. We carry out the reduction in two steps. The first step is a pure four-dimensional cut-integration of tree…

High Energy Physics - Phenomenology · Physics 2010-10-27 Charalampos Anastasiou , Ruth Britto , Bo Feng , Zoltan Kunszt , Pierpaolo Mastrolia

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

A common assumption in both grid-following (GFL) and grid-forming (GFM) control systems is that they are open-loop (OL) stable in the vicinity of high-frequency resonances. Hence classical loop-shaping approaches are often used for…

Systems and Control · Electrical Eng. & Systems 2026-05-05 Meng Chen , Yufei Xi , Frede Blaabjerg , Lin Cheng , Ioannis Lestas

In this paper, I present a technique to simplify the tensorial reduction of one-loop integrals with arbitrary internal masses, but at least two massless external legs. By applying the method to rank l tensor integrals, one ends up with at…

High Energy Physics - Phenomenology · Physics 2009-10-28 R. Pittau

We explore methods to use thermostatically controlled loads (TCLs), such as water heaters and air conditioners, to provide ancillary services by assisting in balancing generation and load. We show that by adding simple imbedded instructions…

Dynamical Systems · Mathematics 2013-01-15 N. A. Sinitsyn , Soumya Kundu , S. Backhaus

A precise understanding of LHC phenomenology requires the inclusion of one-loop corrections for multi-particle final states. In this talk we describe a semi-numerical method to compute one-loop amplitudes with many external particles and…

High Energy Physics - Phenomenology · Physics 2009-11-11 T. Binoth , M. Ciccolini , G. Heinrich

Looped transformers apply a shared block multiple times and have emerged as a parameter-efficient route to scaling compute in language models. However, at fixed FLOPs a looped model has strictly less capacity than a baseline transformer. We…

Computation and Language · Computer Science 2026-05-29 Markus Frey , Behzad Shomali , Joachim Koehler , Mehdi Ali

We develop a unitarity method to compute one-loop amplitudes with massless propagators in d=4-2*epsilon dimensions. We compute double cuts of the loop amplitudes via a decomposition into a four-dimensional and a -2*epsilon-dimensional…

High Energy Physics - Phenomenology · Physics 2008-11-26 Charalampos Anastasiou , Ruth Britto , Bo Feng , Zoltan Kunszt , Pierpaolo Mastrolia

For loop integrals, the standard method is reduction. A well-known reduction method for one-loop integrals is the Passarino-Veltman reduction. Inspired by the recent paper [1] where the tadpole reduction coefficients have been solved, in…

High Energy Physics - Phenomenology · Physics 2022-01-05 Chang Hu , Tingfei Li , Xiaodi Li

We compute the one-loop scalar massless pentagon integral I_5^{6-2 eps} in D=6-2\eps dimensions in the limit of multi-Regge kinematics. This integral first contributes to the parity-odd part of the one-loop N=4 five-point MHV amplitude…

High Energy Physics - Theory · Physics 2010-03-26 Vittorio Del Duca , Claude Duhr , E. W. Nigel Glover , Vladimir A. Smirnov

In this presentation, we review the general features of integrand-reduction techniques, with a particular focus on their generalization beyond one loop. We start with a brief discussion of the one-loop scenario, a case in which…

High Energy Physics - Phenomenology · Physics 2016-08-01 Giovanni Ossola

We present a novel algorithm which can overcome the drawbacks of the conventional linear scaling method with minimal computational overhead. This is achieved by introducing additional constraints, thus eliminating the redundancy of the…

Materials Science · Physics 2015-06-25 Eiji Tsuchida

We present an overview of techniques developed in recent years for the efficient calculation of one-loop multiparton amplitudes, in particular those relying on unitarity and collinear factorization.

High Energy Physics - Phenomenology · Physics 2009-10-30 Zvi Bern , Lance Dixon , David C. Dunbar , David A. Kosower

We propose a systematic way to carry out the method introduced in hep-th/0410077 for computing certain unitarity cuts of one-loop N=4 amplitudes of gluons. We observe that the class of cuts for which the method works involves all…

High Energy Physics - Theory · Physics 2009-11-10 Ruth Britto , Freddy Cachazo , Bo Feng

This article reviews on-shell methods for analytic computation of loop amplitudes, emphasizing techniques based on unitarity cuts. Unitarity techniques are formulated generally but have been especially useful for calculating one-loop…

High Energy Physics - Theory · Physics 2015-05-20 Ruth Britto

We present a numerical implementation for virtual corrections to multi-jet production at Next-to-Leading order. Using the algorithm of generalised unitarity we compute primitive amplitudes from tree-level input. These basic ingredients are…

High Energy Physics - Phenomenology · Physics 2012-01-06 Simon Badger , Benedikt Biedermann , Peter Uwer

Based on the OPP technique and the HELAC framework, HELAC-1LOOP is a program that is capable of numerically evaluating QCD virtual corrections to scattering amplitudes. A detailed presentation of the algorithm is given, along with…

High Energy Physics - Phenomenology · Physics 2013-01-14 G. Bevilacqua , M. Czakon , M. V. Garzelli , A. van Hameren , A. Kardos , C. G. Papadopoulos , R. Pittau , M. Worek

We analytically calculate one- and two-loop helicity amplitudes in massless QED, by adopting a four-dimensional tensor decomposition. We draw our attention to four-fermion and Compton scattering processes to higher orders in the dimensional…

High Energy Physics - Phenomenology · Physics 2024-11-20 Thomas Dave , William J. Torres Bobadilla

We present the program package GoSam which is designed for the automated calculation of one-loop amplitudes for multi-particle processes in renormalisable quantum field theories. The amplitudes, which are generated in terms of Feynman…