ANALYZING POWERS OF SHe(p,p)SHe ELASTIC SCATTERING BETWEEN 20 AND 35 MeV %

In order to supplement the present data base and to improve existin@ ~hase shift analyses, we are measuring analyzing powers for proton-~He elastic scattering between 20 and 35 MeV. A scattering facility featuring an optically pumped polarized SHe target has been constructed. Target polarizations of greater than 20% have been obtained, which compare favorably with SHe polarizations obtained at other laboratories. Glass target cells with very thin entrance windows have been developed to reduce background from multiplyscattered protons. Analyzing power angular distributions have been obtained at 25.0 and 30.0 MeV.