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arXiv · hep-ph/0207107

A Model for the Pion Structure Function

F. Bissey·J. R. Cudell·J. Cugnon·M. Jaminon·J. P. Lansberg·P. Stassart
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Abstract

The pion structure function is investigated in a simple model, where pion and constituent quark fields are coupled through the simplest pseudoscalar coupling. The imaginary part of the forward gamma* pi-> gamma* pi scattering amplitude is evaluated and related to the structure functions. It is shown that the introduction of non-perturbative effects, linked to the size of the pion and preserving gauge invariance, allows a connection with the quark distribution. It is predicted that higher-twist terms become negligible for Q2 larger than about 2 GeV2 and that quarks in the pion have a momentum fraction smaller than in the proton case.

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F. Bissey, J. R. Cudell, J. Cugnon, M. Jaminon, J. P. Lansberg, P. Stassart. 2002-07-08. A Model for the Pion Structure Function. https://doi.org/10.1016/s0370-2693(02)02775-2

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