̄pp backward elastic scattering has been measured for the cos θcm region between – 1.00 and – 0.88 and for the incident̄p laboratory momentum region between 0.70 and 2.37 GeV/c.These measurements, done in intervals of approximately 0.1 GeV/c, have been performed at the Alternating Gradient Synchrotron at Brookhaven National Laboratory during the winter of 1968.The measured differential cross sections, binned in cos θcm intervals of 0.02, have statistical errors of about 10%.Backward dipping exists below 0.95 GeV/c and backward peaking above 0.95 GeV/c.The 180˚ differential cross section extrapolated from our data shows a sharp dip centered at 0.95 GeV/c and a broad hump centered near 1.4 GeV/c.Our data have been interpreted in terms of resonance effects and in terms of diffraction dominance effects.
