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arXiv · hep-ph/9211238

Properties of perturbative multi-particle amplitudes in $ϕ^k$ and $O(N)$ theories

B. H. Smith
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Abstract

Threshold amplitudes are considered for multi-particle production in $ϕ^k$ and $O(N) ~ϕ^4$ theories. It is found that the disappearance of tree-level threshold amplitudes of $2$ on-shell particles producing a large number of particles occurs in $ϕ^k$ theory only for $k=3$ and $k=4$. The one-loop correction to the threshold amplitude for a highly virtual scalar particle decaying into $n$ particles in an $O(N)$ model is derived.

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B. H. Smith. 1992-11-11. Properties of perturbative multi-particle amplitudes in $ϕ^k$ and $O(N)$ theories. https://doi.org/10.1103/physrevd.47.3521

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