Pion-Hydrogen Phase Shift Analysis between 120 and 217 Mev

An analysis has been made of the experimental angular distributions of negative pion---hydrogen scattering between 120 and 217 Mev. The usual assumptions of charge independence, and contributions from S and P waves only, are used and the six phase shifts determined as a function of energy by means of the Los Alamos MANIAC. The resulting phase shifts are used to predict positive pion---hydrogen scattering in this energy region. Comparison with the experimental data on positive pions enables one to exclude some of the sets of solutions obtained from the negative pion data. Essentially three acceptable sets of solutions are found. Arguments are given why one of these is likely to be the physically correct one. Its characteristics are that the predominant phase angle with T=32, j=32 passes through 90^ at about 195 Mev, that none of the other phase angles shows a resonance in our energy region, and that the T=12 phase angles are all small.