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Structure functions of 2d integrable asymptotically free models

Janos Balog·Peter Weisz
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Abstract

We investigate structure functions in the 2--dimensional (asymptotically free) non--linear O$(n) σ$--models using the non--perturbative S--matrix bootstrap program. In particular the {\it exact small (Bjorken) $x$ behavior is exhibited}; the structure is rather universal and is probably the same in a wide class of (integrable) asymptotically free models. Structurally similar universal formulae may also hold for the small $x$ behavior of QCD in 4--dimensions. Structure functions in the special case of the $n=3$ model are accurately computed over the whole $x$ range for $-q^2/M^2<10^5$, and some moments are compared with results from renormalized perturbation theory. Some remarks concerning the structure functions in the $1/n$ approximation are also made.

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Janos Balog, Peter Weisz. 2004-05-04. Structure functions of 2d integrable asymptotically free models. https://doi.org/10.1016/j.physletb.2004.05.018

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