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Structure functions of the 2d O(n) non-linear sigma models

Janos Balog·Peter Weisz
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Abstract

We investigate structure functions in the 2-dimensional (asymptotically free) non-linear O(n) sigma-models using the non-perturbative S-matrix bootstrap program. In particular the exact small (Bjorken) x behavior is derived. 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 results concerning the structure functions in the 1/n approximation are also presented.

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Janos Balog, Peter Weisz. 2004-09-08. Structure functions of the 2d O(n) non-linear sigma models. https://doi.org/10.1016/j.nuclphysb.2004.12.017

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