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HELAC-PHEGAS: automatic computation of helicity amplitudes and cross sections

Aggeliki Kanaki·Costas G. Papadopoulos
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Abstract

HELAC-PHEGAS is a FORTRAN based package that is able to compute automatically and efficiently tree-order helicity amplitudes and cross sections for arbitrary scattering processes within the standard electroweak theory and QCD. The algorithm for the amplitude computation, HELAC, exploits the virtues of the Dyson-Schwinger equations. The phase-space generation algorithm, PHEGAS, constructs all possible kinematical mappings dictated by the amplitude under consideration. Combined with mutichannel self-optimized Monte Carlo integration it results to efficient cross section evaluation.

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Aggeliki Kanaki, Costas G. Papadopoulos. 2000-12-01. HELAC-PHEGAS: automatic computation of helicity amplitudes and cross sections. https://doi.org/10.1063/1.1405294

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