Measurement of elastic scattering in antiproton-proton collisions at 52.8 GeV centre-of-mass energy

The authors measured the differential cross section for pp and pp elastic scattering in the momentum-transfer range 0.01< mod t mod <1.0 GeV/sup 2/ at the CERN Intersecting Storage Rings with center-of-mass energy \sqrt{s}=52.8 GeV. Fitting the differential cross section with an exponential (A exp (bt)), they found b/sub pp/=13.92+or-0.59 GeV/sup -2/ for mod t mod <0.05 GeV/sup 2/, whilst for mod t mod >0.09 GeV/sup 2/, b/sub pp/=10.68+or-0.26 GeV/sup -2/. Using the optical theorem, they obtained the total cross section sigma /sub tot/(pp) =44.86+or-0.78 mb and, by integrating the differential cross section, the total elastic cross section sigma /sub el/(pp)=7.89+or-0.28 mb. Calculations of sigma /sub tot/ combining elastic-rate and total-rate measurements are also given. All of these measurements were also performed for pp scattering at the same energy, and the results for both reactions are compared.