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arXiv · 0707.2208

Breakdown of chiral expansion for parton distributions

N. Kivel·M. V. Polyakov
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Abstract

In the framework of the chiral perturbation theory we computed two- and three-loop corrections to the pion parton distributions which posses $δ$-function singularities at x->0. This calculation explicitly demonstrates that in the region of small x ~ mpi^2/(4 pi F)^2 standard ChPT breaks down and one needs resummation of all orders. We give an example of such resummation.

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N. Kivel, M. V. Polyakov. 2008-06-05. Breakdown of chiral expansion for parton distributions. https://doi.org/10.1016/j.physletb.2008.04.048

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