The Status of the SPRING8 Project

A polarized high energy photon beam line was constructed by means of Compton back scattering of laser light against 8 GeV electrons circulating in the SPring-8 storage ring. The intensity is 2.5 × 10⁶/s at maximum for the full energy spectrum up to 2.4GeV, at the electron current of 100mA with the laser power of 5W. Interesting physics programs to be performed at the beam line were submitted as letters of intents. One of them is the GDH experiment where the helicity dependent total photo-absorption cross-section will be measured from 1.8 GeV to 2.8 GeV. Preparation of the experiment are in progress.