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arXiv · hep-ph/0309179

Instanton contribution to the pion and proton formfactors at Q^2 greater than 1 GeV^2

P. Faccioli·A. Schwenk·E. V. Shuryak
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Abstract

Studying the instanton-induced contributions to various hard exclusive reactions provides physical insight into the transition from the non-perturbative to the perturbative regime of QCD. To this end, we study the leading-instanton contribution to the electro-magnetic and transition formfactors, using an effective theory of the Instanton Liquid Model. We report predictions for the space-like electro-magnetic formfactor of the pion, as well as recent results for the Dirac formfactor of the proton.

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P. Faccioli, A. Schwenk, E. V. Shuryak. 2003-10-30. Instanton contribution to the pion and proton formfactors at Q^2 greater than 1 GeV^2. https://arxiv.org/abs/hep-ph/0309179

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