SCATPI, a subroutine for calculating. pi. N cross sections and polarizations for incident pion kinetic energies between 90 and 300 MeV. [In FORTRAN for CDC 6600 and 7600 and Xerox Sigma 7]

Abstract

A subroutine, SCATPI, has been written which calculates T + p and ~~p elastic differential cross sections for incident pion kinetic energies between 90 and 310 MeV for -+ p and 88 and 290 MeV for -n~p. The calculation is based upon the phase shift analysis of Carter, Bugg/and Carter, and is reliable to about 2% for TT + P and 'M for ~~p differential cross sections. SCATPI also calculates other scattering parameters for the TT ± P systems. The calculations are compared with the measurements used in the phase shift analysis, and with selected recent measurements. The use of SCATPI is described. I.

Measurement and isobar-model analysis of the doubly differential cross section for the. pi. /sup +/ produced in. pi. /sup -/p. -->. pi. /sup +/. pi. /sup -/n

“…Tr + p elastic scattering was measured at several angles for which27 At 141 MeV, the cross section for IT + mesons is known with two or three times the accuracy as that for 7r~ mesons. The predictions of SCATPI at this energy allowed com¬ parisons with the known differential cross section at the 1% level.Thus, each IT beam provided an individual test for a possible systematic variation in the solid angle acceptance of the spectrometer with angle.…”