Injection and transport of beams of positrons into and through an octant of LEP

In July 1988 the first successful injection and transport of a beam of positrons at approximately 18 GeV through the first completed octant of LEP (Large Electron-Positron collider) was achieved on the first shot. Subsequently, many beam tests were performed on LEP hardware and measurements made on the optics parameters. Detailed analyses are given on the betatron phase advance per cell for several optics configurations and the magnetic reproducibility. The injection errors and the momentum deviation were measured by fitting a betatron trajectory through the position monitor readings. Following correction of these errors the measured residual deviations were used to estimate alignment errors. These turned out to be significantly smaller than expected. The betatron phase advances in the arc were determined from a difference measurement of trajectories obtained with two opposite settings of single corrector magnets. This showed a slight (but easily correctable) phase difference between the horizontal and vertical planes.<>