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arXiv · 1006.0710

Scattering AMplitudes from Unitarity-based Reduction Algorithm at the Integrand-level

P. Mastrolia·G. Ossola·T. Reiter·F. Tramontano
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Abstract

SAMURAI is a tool for the automated numerical evaluation of one-loop corrections to any scattering amplitudes within the dimensional-regularization scheme. It is based on the decomposition of the integrand according to the OPP-approach, extended to accommodate an implementation of the generalized d-dimensional unitarity-cuts technique, and uses a polynomial interpolation exploiting the Discrete Fourier Transform. SAMURAI can process integrands written either as numerator of Feynman diagrams or as product of tree-level amplitudes. We discuss some applications, among which the 6- and 8-photon scattering in QED, and the 6-quark scattering in QCD. SAMURAI has been implemented as a Fortran90 library, publicly available, and it could be a useful module for the systematic evaluation of the virtual corrections oriented towards automating next-to-leading order calculations relevant for the LHC phenomenology.

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P. Mastrolia, G. Ossola, T. Reiter, F. Tramontano. 2010-06-03. Scattering AMplitudes from Unitarity-based Reduction Algorithm at the Integrand-level. https://doi.org/10.1007/jhep08(2010)080

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