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arXiv · 1011.6632

Modern Feynman Diagrammatic One-Loop Calculations

Thomas Reiter·Gavin Cullen·Nicolas Greiner·Alberto Guffanti·Jean-Philippe Guillet·Gudrun Heinrich·Stefan Karg·Nikolas Kauer·Tobias Kleinschmidt·Maciej Koch-Janusz·Gionata Luisoni·Pierpaolo Mastrolia·Giovanni Ossola·Eric Pilon·Mark Rodgers·Francesco Tramontano·Ioan Wigmore
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Abstract

In this talk we present techniques for calculating one-loop amplitudes for multi-leg processes using Feynman diagrammatic methods in a semi-algebraic context. Our approach combines the advantages of the different methods allowing for a fast evaluation of the amplitude while monitoring the numerical stability of the calculation. In phase space regions close to singular kinematics we use a method avoiding spurious Gram determinants in the calculation. As an application of our approach we report on the status of the calculation of the amplitude for the process $pp\to b\bar{b}b\bar{b}+X$.

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Thomas Reiter, Gavin Cullen, Nicolas Greiner, Alberto Guffanti, Jean-Philippe Guillet, Gudrun Heinrich, Stefan Karg, Nikolas Kauer, Tobias Kleinschmidt, Maciej Koch-Janusz, Gionata Luisoni, Pierpaolo Mastrolia, Giovanni Ossola, Eric Pilon, Mark Rodgers, Francesco Tramontano, Ioan Wigmore. 2010-11-30. Modern Feynman Diagrammatic One-Loop Calculations. https://doi.org/10.22323/1.131.0003

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