S@M, a mathematica implementation of the spinor-helicity formalism

Abstract

In this paper we present the package S@M (Spinors@Mathematica) which implements the spinor-helicity formalism in Mathematica. The package allows the use of complex-spinor algebra along with the multi-purpose features of Mathematica. The package defines the spinor objects with their basic properties along with functions to manipulate them. It also offers the possibility of evaluating the spinorial objects numerically at every computational step. The package is therefore well suited to be used in the context of on-shell technology, in particular for the evaluation of scattering amplitudes at tree- and loop-level. Program summary Program title: S@M Catalogue identifier: AEBF_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEBF_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 14 404 No. of bytes in distributed program, including test data, etc.: 77 536 Distribution format: tar.gz Programming language: Mathematica Computer: All computers running Mathematica Operating system: Any system running Mathematica Classification: 4.4, 5, 11.1 Nature of problem: Implementation of the spinor-helicity formalism Solution method: Mathematica implementation Running time: The notebooks provided with the package take only a few seconds to run.