ELASTIC PROTON-PROTON SCATTERING AT GEV ENERGIES: ANALYZING POWERS ANAND SPIN CORRELATION PARAMETERS ANN, ASS, AND ASL

The analyzing powers ANand spin correlation parameters ANN, ASS, and ASLof the elastic proton-proton scattering have been measured with an internal polarized atomic beam target at the cooler synchrotron COSY. Excitation functions were taken continuously during the acceleration and deceleration of the internal beam for kinetic energies ranging between 0.45 and 2.5 GeV and scattering angles 30°≤Θc.m.≤90°. The analyzing power excitation functions provide a new polarization standard in the GeV region. The spin correlation data on ASSdisagree strikingly with existing phase shift solutions. The addition of the new polarization data to the world database removes some of the ambiguities in the phase shift solutions and the direct reconstruction of scattering amplitudes. The data are compared with a recent extension of a meson-exchange potential model to higher energies.

COMPLETE DETERMINATION OF REACTION AMPLITUDES

The reaction amplitudes 〈jcmc;jdmd|T|jama;jbmb〉 for a+b→c+d, with arbitrary spins jv, are completely determined if one carries out measurements of a subset of final state spin correlation parameters [Formula: see text] where the index ‘s’ denotes appropriate initial spin preparations.