Scattering of Pions by Hydrogen at 165 Mev

Abstract

Measurements of the elastic scattering of both positive and negative pions, and of the charge exchange scattering of negative pions were carried out at each of five angles, at 165 Mev using a liquid hydrogen target. In addition, the total cross sections for positive and negative pions were measured by the transmission method. Integration of the differential measurements gave total cross sections of 199\ifmmode\pm\else\textpm\fi{}11 mb for the positive, and 69.8\ifmmode\pm\else\textpm\fi{}3.8 mb for the negative pions. The corresponding cross sections obtained by transmission were 188.2\ifmmode\pm\else\textpm\fi{}5.4 mb and 67.5\ifmmode\pm\else\textpm\fi{}1.5 mb, respectively.A least squares analysis was carried out on the seventeen data to determine the most probable values of the phase shifts, limiting the analysis to $s$ and $p$ waves. Seven solutions were found, three being of the Fermi type, the others of the Yang type. The Fermi type solutions gave ${\ensuremath{\alpha}}_{33}$ near 63\ifmmode^\circ\else\textdegree\fi{}, ${\ensuremath{\alpha}}_{3}$ near -20\ifmmode^\circ\else\textdegree\fi{}, with the other phase shifts small.