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arXiv · hep-ph/9209270

Comment on "Summing One-Loop Graphs at Multi-Particle Threshold"

M. B. Voloshin
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Abstract

The propagator of a virtual $ϕ$-field with emission of $n$ on-mass-shell particles all being exactly at rest is calculated at the tree-level in $λϕ^4$ theory by directly solving recursion equations for the sum of Feynman graphs. It is shown that the generating function for these propagators is equivalent to a Fourier transform of the recently found Green's function within the background-field technique for summing graphs at threshold suggested by Lowell Brown. Also the derivation of the result that the tree-level on-mass-shell scattering amplitudes of the processes $2 \to n$ are exactly vanishing at threshold for $n > 4$ is thus given in the more conventional Feynman diagram technique.

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M. B. Voloshin. 1992-09-23. Comment on "Summing One-Loop Graphs at Multi-Particle Threshold". https://doi.org/10.1103/physrevd.47.1712

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