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arXiv · hep-ph/9301255

Calculation of processes involving many particles at the kinematical threshold

Brian Hendee Smith
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Abstract

A diagrammatic technique is derived for calculating processes involving the production of large numbers of particles. As an example, the amplitude of three particles scattering into $n$ particles at the kinematical threshold in $λϕ^4$ theory is calculated. From the $3 \to n$ amplitude, it is seen that the one-loop amplitude for $2 \to n$ processes is suppressed by a factor of $1/n$.

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Brian Hendee Smith. 1993-01-21. Calculation of processes involving many particles at the kinematical threshold. https://arxiv.org/abs/hep-ph/9301255

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