Progress report on the LEP Pre-injector

The LEP (Large Electron Positron Collider) Pre-injector (LPI) reliably provided positrons and electrons at 500 MeV for the LEP injector chain during the first LEP injection tests. Later, experiments were performed with the LEP Injector Linacs (LIL) to verify the influence of various parameters on the positron current and on the conversion efficiency. Also reported are experiments done with the Electron-Positron Accumulation ring (EPA) operating at 500 MeV, concerning trapping, accumulation, and equilibrium beam parameters. The cutting of eight bunches by a thin electrostatic septum to produce two batches of eight bunches was successfully tested. In addition, first runs with e/sup +/ and e/sup -/ at 600 MeV showed that LPI behaves as expected at this energy.