Sendai Nuclear Science Colloquium (No. 167)

First Double Polarization Measurements towards the test of the Gerasimov-Drell-Hearn Sum Rule at MAMI (Mainz) and ELSA (Bonn)

Werner Meyer

Bochum University 教授

日時：2003年03月13日（木） 15:30-

場所：東北大学原子核理学研究施設３Ｆ会議室

A direct measurement of the helicity dependence of the total inclusivephotoabsorption cross section on the proton was carried out in theenergy range from 200 up to 3000 MeV for the first time. Theexperiments were performed at the Mainz accelerator facility MAMI(200-800 MeV) and at the Bonn accelerator ELSA (800-3000 MeV).4π detector systems, circularly polarized tagged photon beams anda newly developed polarized solid target were used. The data obtainedprovide new information for multipole analyses of pion photoproductionand give contributions to the Gerasimov-Drell-Hearn (GDH) sum rule.