HELAS and MadGraph/MadEvent with spin-2 particles
نویسندگان
چکیده
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 HELAS (HELicity Amplitude Subroutines) library. They are coded in such a way that arbitrary scattering amplitudes with one graviton production and its decays can be generated automatically by MadGraph and 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. KEK-TH-1218 KA-TP-02-2008 SFB/CPP-08-02 KIAS-P08036 May 16, 2008
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