Measurement of ρ, the ratio of the real to the imaginary part of thep¯pforward elastic-scattering amplitude, at √s=1.8 TeV

Abstract
We have measured ρ, the ratio of the real to the imaginary part of the p¯p forward elastic-scattering amplitude, at √s =1.8 TeV. Our result, ρ=0.140±0.069, is compared with extrapolations from lower-energy data based on dispersion relations, and with the UA4 value at √s =546 GeV.