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arXiv · hep-ph/9402280

The Pion Form Factor. Where Does It Come From?

A. Zhitnitsky
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Abstract

We discuss the nonleading, ``soft" contribution to the pion form factor at intermediate momentum transfer within operator product expansion approach. We argue, that the corresponding contribution can temporarily {\bf simulate} the leading twist behavior in the extent region of $ Q^2:~~3 GeV^2\leq Q^2\leq 35 GeV^2 $, where $Q^2 F(Q^2)\sim const.$ Such a mechanism, if it is correct, would be an explanation of the phenomenological success of the dimensional counting rules (which theoretically correspond to the keeping of the asymptotically leading terms only) at available, very modest $Q^2$. The relation with quark model calculation is also discussed.

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A. Zhitnitsky. 1994-09-08. The Pion Form Factor. Where Does It Come From?. https://arxiv.org/abs/hep-ph/9402280

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