Study of the reaction π-p → eta n in the region of the N*(1688)

In an experiment performed at the Bevatron, a negative-pion beam incident on a 20-cm liquid-hydrogen target produced reactions of the form π/sup -/p → neutral final state. The final-state neutron was detected by plastic-scintillator counters. The final-state photons were detected by lead-plate spark chambers, which covered about 3.7 π solid angle, or by lead-scintillator sandwich counters, which covered most of the open face of the spark-chamber array. For this analysis, a kinematic fit was done on the L. B. L. computer for each event in which two photons were detected. For each momentum, events which fit the hypothesis π/sup -/p → eta n were binned according to the calculated production cosine, and the resulting distributions were corrected by comparing to the results of a Monte-Carlo calculation for the same reaction. The differential cross section was calculated for each bin, and the values for each momentum were fit to a sum of Legendre polynomials in production cosine. In the final chapter, the Legendre polynomial coefficients, the total cross section, and the differential cross sections extrapolated to 00 and 1800 are compared to the results of other experiments, and some speculations are offered as to the spin-parity states which affect the measured behavior of the reaction. The conclusion is drawn that the N (1688) does not contribute, but that the N (1670) does, with a cross section of (0.84 +- 0.21) mb. (U.S.)