Al Collisions Research Articles

Neutral meson production by 930 MeV protons

The production of neutral mesons in pC and pAl collisions has been studied using total absorption Čerenkov counters. The counters were tested in gamma ray beams arising from π 0 production in internal targets in the synchrotron. Total cross sections for π 0 production from carbon at 930 and 660 MeV were 69±14 and 21±9 mb. The angular distribution of gamma rays, in the nucleon-nucleon centre of mass, at 930 MeV, was 1 − (0.2 ± 0.3) cos θ + (0.9 ± 0.3) cos 2 θ. From this the angular distribution of mesons in proton-nucleon collisions is deduced as being 1 + (2.6 ± 1.6) cos 2 θ.