ETA-MESON PRODUCTION IN PD AND PP COLLISIONS

The doubly-differential cross sections for the pp --> pp eta and pd -- > eta X reactions have been measured at incident proton energies of 1. 3 and 1.5 GeV. The ratio of the pd to pp-induced cross sections varies from about 8-10 at 1.3 GeV to 4.5-6 at 1.5 GeV in the eta kinetic ene rgy interval 100 MeV less than or equal to T-eta less than or equal to 220 MeV. Information on the pn --> eta X reaction has been extracted from these measurements within the framework of a simple folding model .