Photoproduction Experiment with Polarized Target at SPring-8

摘要

Measurement of double polarization asymmetries for ? photoproduction with the polarized target and a polarized photon beam is a sensitive means to investigate small and exotic amplitudes, such as an ss-quark content of nucleons, via interferences with dominant amplitudes and the determination of the spin value of produced hadrons as the pentaquark. In order to realize the double polarization measurements to study the ss-quark content as well as exotic hadron structures, We started to construct a frozen-spin polarized HD target at the LEPS facility on the new basis of recent technology developments in cryogenic and high magnetic field. We discuss the experiment for ?-meson photoproduction which will be performed in 10 days (40 days) with the result of 20% (10%) accuracy for the double polarization asymmetry measurement.