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Pion Electroproduction on the Nucleon and the Generalized GDH Sum Rule

L. Tiator·D. Drechsel·S. S. Kamalov
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Abstract

We present predictions for the spin structure functions of the proton and the neutron in the framework of a unitary isobar model for one-pion photo- and electroproduction. Our results are compared with recent experimental data from SLAC. The first moments of the calculated structure functions fulfill the Gerasimov-Drell-Hearn and Burkhardt-Cottingham sum rules within an error of typically 5-10% for the proton. For the neutron target we find much bigger deviations, in particular the sum rule for I_1(0)+I_2(0) is heavily violated.

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L. Tiator, D. Drechsel, S. S. Kamalov. 1999-09-28. Pion Electroproduction on the Nucleon and the Generalized GDH Sum Rule. https://arxiv.org/abs/nucl-th/9909068

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