Skip to content

First measurement of the Gerasimov-Drell-Hearn integral for Hydrogen from 200 to 800 MeV

GDH-Collaboration, A2-Collaboration, :, J. Ahrens

hep-exarXiv:hep-ex/0105089

Abstract

A direct measurement of the helicity dependence of the total photoabsorption cross section on the proton was carried out at MAMI (Mainz) in the energy range 200 < Egamma < 800 MeV. The experiment used a 4π detection system, a circularly polarized tagged photon beam and a frozen spin target. The contributions to the Gerasimov-Drell-Hearn sum rule and to the forward spin polarizability γ0 determined from the data are 226 5 (stat) 12(sys) μb and -187 8 (stat) 10(sys)10-6 fm4, respectively, for 200 < Eγ< 800 MeV.

Create a lesson