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تسجيل مستخدم جديدHELAS and MadGraph/MadEvent with spin-2 particles
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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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J. P. B. C. de Melo
, Anace N. da Silva (Laboratorio de Fisican Teorica e Computacional
, LFTC
2015
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