Tagged Virtual Photons in the South Hall Ring

An extreme forward-angle electron scattering capability is being investigated for the South Hall Ring (SHR), to be used in conjunction with internal polarized gas targets. For , there is a direct correspondence with real photo-reactions. Linear polarizations as high as 80%are expected for photons ranging from MeV. Projected luminosities of cms are expected. Using polarized H, D, and He internal gas targets with a 4 hadron detector, double polarization observables in - production could be mapped out, and polarization degrees of freedom in few- body reactions could be studied in detail. Low density gas targets present negligble energy-loss to recoiling charged hadrons allowing measurements in the vicinity of meson thresholds. Initial tests of this concept will be carried out in the near future.