A precision measurement of pp elastic scattering cross-sections at intermediate energies

Abstract

We have measured differential cross sections for pp elastic scattering with internal fiber targets in the recirculating beam of the proton synchrotron COSY. Measurements were made continuously during acceleration for projectile kinetic energies between 0.23 and 2.59 GeV in the angular range 30 ◦ ≤ �c.m. ≤ 90 ◦ . Details of the apparatus and the data analysis are given and the resulting excitation functions and angular distributions presented. The precision of each data point is typically better than 4%, and a relative normalization uncertainty of only 2.5% within an excitation function has been reached. The impact on phase shift analysis as well as upper bounds on possible resonant contributions in lower partial waves are discussed. PACS. 25.40.Cm Elastic proton scattering - 13.75.Cs Nucleon-nucleon interactions - 13.85.Dz Elastic scattering - 21.30.-x Nuclear forces