Title :
Operational procedures to obtain high beam-beam tune shifts in LEP pretzel operation
Author :
Bailey, R. ; Collier, P. ; Bohl, T. ; Burkhardt, H. ; Cornelis, K. ; de Rijk, G. ; Faugier, A. ; Jonker, M. ; Lamont, M. ; Roy, G. ; Schmickler, H. ; Wenninger, J.
Author_Institution :
CERN, Geneva, Switzerland
Abstract :
During the running period 1994 the luminosity of LEP has been improved without colliding higher bunch currents. This paper describes the main procedures used by the operations group for luminosity optimization. Separator scans in the vertical plane and orbit interpolations in the horizontal plane are used to adjust settings for electrostatic separators in order to ensure head-on collisions. The closed orbit is corrected towards a reference orbit (called “golden” orbit) which has been found empirically to produce good luminosity. The settings of the skew quadrupoles for coupling compensation is obtained by measuring the closest tune approach of the horizontal and vertical betatron tunes
Keywords :
beam handling techniques; electron accelerators; particle beam dynamics; storage rings; synchrotrons; LEP pretzel operation; closed orbit; colliding higher bunch currents; coupling compensation; electrostatic separators; golden orbit; head-on collisions; high beam-beam tune shifts; luminosity; luminosity optimization; orbit interpolations; reference orbit; separator scans; skew quadrupoles; Electrostatic measurements; Extraterrestrial measurements; Interpolation; Optical coupling; Particle beams; Particle separators; Radiation detectors;
Conference_Titel :
Particle Accelerator Conference, 1995., Proceedings of the 1995
Conference_Location :
Dallas, TX
Print_ISBN :
0-7803-2934-1
DOI :
10.1109/PAC.1995.504715
