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A Model for the Off-forward Structure Functions of the Pion

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

We extend our model for the pion, which we used previously to calculate its diagonal structure function, to the off-forward case. The imaginary part of the off-forward gamma* pi -> gamma* pi scattering amplitude is evaluated in the chiral limit (m_pi=0) and related to the twist-two and twist-three generalised parton distributions, H, H3, H3tilde. Non-perturbative effects, linked to the size of the pion and still preserving gauge invariance, are included. Remarkable new relations between H, H3 and H3tilde are obtained and discussed.

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F. Bissey, J. R. Cudell, J. Cugnon, J. P. Lansberg, P. Stassart. 2004-03-05. A Model for the Off-forward Structure Functions of the Pion. https://doi.org/10.1016/j.physletb.2004.03.023

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