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arXiv · hep-ph/0212033

Spin structure of the nucleon at low energies

Véronique Bernard·Thomas R. Hemmert·Ulf-G. Meißner
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Abstract

The spin structure of the nucleon is analyzed in the framework of a Lorentz-invariant formulation of baryon chiral perturbation theory. The structure functions of doubly virtual Compton scattering are calculated to one-loop accuracy (fourth order in the chiral expansion). We discuss the generalization of the Gerasimov-Drell-Hearn sum rule, the Burkhardt-Cottingham sum rule and moments of these. We give predictions for the forward and the longitudinal-transverse spin polarizabilities of the proton and the neutron at zero and finite photon virtuality. A detailed comparison to results obtained in heavy baryon chiral perturbation theory is also given.

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Véronique Bernard, Thomas R. Hemmert, Ulf-G. Meißner. 2002-12-03. Spin structure of the nucleon at low energies. https://doi.org/10.1103/physrevd.67.076008

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