Measurement of helicity dependent total inclusive γ–3He cross section and the GDH sum rule on the neutron

Abstract

A first experiment using a polarised 3He target has been carried out in Mainz at the MAMI accelerator, with the aim of investigate the Gerasimov-Drell-Hearn sum rule on the neutron. In fact, due to the spin structure of 3He, the data obtained with the polarised 3He target give a complementary and more direct access to the neutron compared to the existing data on the deuteron. Results of the unpolarised and helicity dependent total photoabsorption cross section γ3He → X, of the pion photoproduction channels γ3He → πX and of the γ3He → ppn channel, obtained in a photon energy range between 200 MeV and 500 MeV, will be presented.