COSY - A Cooler Synchrotron and Storage Ring

Abstract

The storage ring COSY with phase space cooling and RF acceleration is designed to accept protons and light ions injected from the existing cyclotron JULIC or protons from the LINAC of the proposed neutron spallation source (SNQ). The lay-out of COSY was developed in cooperation with the Universities in Nordrhein-Westfalen and meets the experimental requirements of variable and high quality beams which are necessary for future nuclear research under discussion. The motivation for the cooler-synchrotron COSY emerged from discussions of nuclear physicists in Nordrhein-Westfalen on future research activities. The Workshop on Electron Coolinq in 1982 came to the conclusion that a cooler-synchrotron I is an excellent tool for advanced nuclear research experiments. It should be built at the KFA in cooperation with the surrounding Universities. The three essential properties of the storage ring will be: - high luminosities and very efficient use of the beam in the storage ring by thin internal targets - energy variability in the range of 20 MeV to 1.5 GeV by RF acceleration - very high beam quality through phase space cooling. Two classes of experiments will be feasible in the first step of construction. At proton energies up to about 200 MeV it will be possible to excite selectively fundamental nuclear spin isospin modes and to resolve the corresponding nuclear levels with the existing high resolution spectrometer BIG KARL'. At higher energies single nucleons in the nucleus can be excited internally and coherent meson production can be studied, processes which reflect details of the subnuclear structure.