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arXiv · hep-ph/9803329

Quark Distribution in Pion within Instanton Liquid Model

A. E. Dorokhov·Lauro Tomio
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Abstract

The leading-twist valence-quark distribution function in the pion is obtained at a low normalization scale of an order of the inverse average size of an instanton $ρ_c$. The momentum dependent quark mass and the quark-pion vertex are constructed in the framework of the instanton liquid model, using a gauge invariant approach. The parameters of instanton vacuum, the effective instanton radius and quark mass, are related to the vacuum expectation values of the lowest dimension quark-gluon operators and to the pion low energy observables. An analytic expression for the quark distribution function in the pion for a general vertex function is derived. The results are QCD evolved to higher momentum-transfer values, and reasonable agreement with phenomenological analyzes of the data on parton distributions for the pion is found.

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A. E. Dorokhov, Lauro Tomio. 1998-10-13. Quark Distribution in Pion within Instanton Liquid Model. https://arxiv.org/abs/hep-ph/9803329

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