HIGH-ENERGY ELASTIC SCATTERING OF PI+-, K-, AND PBAR ON HYDROGEN AT CM ANGLES FROM 22 DEGREES TO 180 DEGRESS

Elastic π±-p, K - p, and p̄-p scattering cross sections have been measured using three different experimental arrangements covering the c.m. angular regions ∼20°-120°, ∼135°-169°, and ∼165°-180°at incident momenta from 6 to 17 GeV/c. In the region 130°-180°, only π±-p scattering was measured. In the angular region near 180°, the energy dependences and shapes of the π-p backward peaks were determined up to crossed-momentum transfers of u∼-2 (GeV/c)2. At all energies, the π+-p backward peak had a sharp dip at u=-0.13 (GeV/c)2, with no similar effect in the π - p case. Nearly complete angular distributions of π - p elastic scattering from 20°to 180°have been obtained at 6 and 10 GeV/c. These results at 6 and 10 GeV/c as well as at 8 GeV/c reveal a sharp dip in π - p scattering at t=-3 (GeV/c)2. Several structures in the form of dips or shoulders were seen in the p̄-p angular distributions also, with less pronounced structure observed in K - p scattering. At fixed momentum transfer, all cross sections when expressed as dσdt appear to be decreasing with increasing energy. © 1969 The American Physical Society.