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arXiv · 0805.2554

HELAS and MadGraph/MadEvent with spin-2 particles

Kaoru Hagiwara·Junichi Kanzaki·Qiang Li·Kentarou Mawatari
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Abstract

Fortran subroutines to calculate helicity amplitudes with massive spin-2 particles (massive gravitons), which couple to the standard model particles via the energy momentum tensor, are added to the {\tt HELAS} ({\tt HEL}icity {\tt A}mplitude {\tt S}ubroutines) library. They are coded in such a way that arbitrary scattering amplitudes with one graviton production and its decays can be generated automatically by {\tt MadGraph} and {\tt MadEvent}, after slight modifications. All the codes have been tested carefully by making use of the invariance of the helicity amplitudes under the gauge and general coordinate transformations.

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Kaoru Hagiwara, Junichi Kanzaki, Qiang Li, Kentarou Mawatari. 2008-05-16. HELAS and MadGraph/MadEvent with spin-2 particles. https://doi.org/10.1140/epjc%2Fs10052-008-0663-x

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