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arXiv · hep-ph/0208173

The Valence Quark Distribution of the Pion

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

The pion structure function is investigated in a simple model, where the pion and its 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, allows a connection with the quark distribution. It is predicted that higher-twist terms become negligible for Q^2 larger than ~2 GeV^2, that quarks in the pion have a momentum fraction smaller than in the proton case, and that the momentum sum rule is violated for the pion.

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J. P. Lansberg, F. Bissey, J. R. Cudell, J. Cugnon, M. Jaminon, P. Stassart. 2002-08-19. The Valence Quark Distribution of the Pion. https://arxiv.org/abs/hep-ph/0208173

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