Antiproton-Proton Cross Sections at 1.0, 1.25, and 2.0 Bev

The interaction of 1.0-, 1.25-, and 2.0-Bev antiprotons with protons has been studied with the aid of a $4\pi$ solid-angle scintillation-counter detector system. The measured total cross sections at the above energies are 100, 89, and 80 mb, respectively. At each energy, the charge-exchange cross section is approximately 5 mb. The total elastic cross sections are 33, 28, and 25 mb, respectively, at the three energies. The angular distribution of elastic scattering has been fitted with a simple optical-model calculation.