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arXiv · 1610.09994

Do fragmentation functions in factorization theorems correctly treat non-perturbative effects?

John Collins
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Abstract

Current all-orders proofs of factorization of hard processes are made by extracting the leading power behavior of Feynman graphs, i.e., by extracting asymptotics strictly order-by-order in perturbation theory. The resulting parton densities and fragmentation functions include non-perturbative effects. I show how there are missing elements in the proofs; these are related to and exemplified by string and cluster models of hadronization. The proofs rely on large rapidity differences between different parts of graphs for the process; but in reality large rapidity gaps are filled in

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John Collins. 2016-10-31. Do fragmentation functions in factorization theorems correctly treat non-perturbative effects?. https://arxiv.org/abs/1610.09994

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