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arXiv · 1002.1968

Pion form factor from a contact interaction

L. X. Gutierrez-Guerrero·A. Bashir·I. C. Cloet·C. D. Roberts
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Abstract

In a Poincare'-covariant vector-boson-exchange theory, the pion possesses components of pseudovector origin, which materially influence its observable properties. For a range of such quantities, we explore the consequences of a momentum-independent interaction, regularised in a symmetry-preserving manner. The contact interaction, whilst capable of describing pion static properties, produces a form factor whose: evolution for Q^2>0.17GeV^2 disagrees markedly with experiment; and asymptotic power-law behaviour conflicts strongly with perturbative-QCD.

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L. X. Gutierrez-Guerrero, A. Bashir, I. C. Cloet, C. D. Roberts. 2010-02-09. Pion form factor from a contact interaction. https://doi.org/10.1103/physrevc.81.065202

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