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Calculating two- and three-body decays with FeynArts and FormCalc

Michael Klasen
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Abstract

The Feynman diagram generator FeynArts and the computer algebra program FormCalc allow for an automatic computation of 2->2 and 2->3 scattering processes in High Energy Physics. We have extended this package by four new kinematical routines and adapted one existing routine in order to accomodate also two- and three-body decays of massive particles. This makes it possible to compute automatically two- and three-body particle decay widths and decay energy distributions as well as resonant particle production within the Standard Model and the Minimal Supersymmetric Standard Model at the tree- and loop-level. The use of the program is illustrated with three standard examples: h->b\bar{b}, μ->e\barν_eν_μ, and Z->ν_e\barν_e.

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Michael Klasen. 2002-10-30. Calculating two- and three-body decays with FeynArts and FormCalc. https://doi.org/10.1142/s012918310300539x

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