English

HELAS and MadGraph/MadEvent with spin-2 particles

High Energy Physics - Phenomenology 2008-11-26 v1

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.

Keywords

Cite

@article{arxiv.0805.2554,
  title  = {HELAS and MadGraph/MadEvent with spin-2 particles},
  author = {Kaoru Hagiwara and Junichi Kanzaki and Qiang Li and Kentarou Mawatari},
  journal= {arXiv preprint arXiv:0805.2554},
  year   = {2008}
}

Comments

11 pages, 2 figures

R2 v1 2026-06-21T10:41:30.853Z