Helicity dependence of the interaction and the GDH sum rule
INFN-Sezione di Pavia, via Bassi 6, Pavia, Italy
* e-mail: firstname.lastname@example.org
First measurements of pion photoproduction using circularly polarized photons on longitudinally polarized protons were carried out at MAMI (Mainz) in the energy range -800 MeV. Results of the helicity dependence of the total inclusive photoabsorption cross-section and of the pion photoproduction channels will be presented. These data provide new input for multipole analyses and determine the main contribution to the Gerasimov-Drell-Hearn integral and the forward spin polarizability .
© Società Italiana di Fisica and Springer-Verlag, 2003