Forward angle analyzing power in p→-n and p→-p quasifree scattering at 643 and 797 MeV

Polarized proton beams and a liquid-deuterium target were used to measure the analyzing power for quasifree p→-n and p→-p scattering in the forward direction at 643 and 797 MeV. Alternate use of a liquid-hydrogen target provided a comparison of free and quasifree p→-p scattering. The precision of the data is in general ±0.01 to ±0.02, although some of the p→-p data for 797 MeV are at the precision level of ±0.005. For c.m. angles θ^*≥22° there is no difference between quasifree and free results at either energy. The data are compared with the predictions of several phase-shift analyses. In a search for more pronounced quasifree scattering effects, a small amount of p→-‘‘p’’ data were taken with a carbon target.