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Renormalization Group for Multiparticle Production in (2+1) Dimensions Around the Threshold

V. A. Rubakov·D. T. Son
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Abstract

Multiparticle production in (2+1) dimensions is investigated. We show that in a small region around the threshold the perturbation theory becomes unapplicable due to infrared divergencies in a class of Feynman graphs with rescattering in final state. We develop a technique based on renormalization group for summing up leading logarithms and apply it to the $ϕ^4$ models with and without symmetry breaking and to the $O(N)$ $ϕ^4$ theory.

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V. A. Rubakov, D. T. Son. 1994-06-22. Renormalization Group for Multiparticle Production in (2+1) Dimensions Around the Threshold. https://arxiv.org/abs/hep-ph/9406362

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