Tevatron Electron Lenses: Design and Operation

• Published in: Physical review special topics. PRST-AB. Accelerators and beams Vol. 11; no. 10
• Main Authors: Shiltsev, Vladimir, /Fermilab, Bishofberger, Kip, /Los Alamos, Kamerdzhiev, Vsevolod, Kozub, Sergei, /Serpukhov, IHEP, Kufer, Matthew, Kuznetsov, Gennady, Martinez, Alexander, Olson, Marvin, Pfeffer, Howard, Saewert, Greg, Scarpine, Vic, Seryi, Andrei, /SLAC, Solyak, Nikolai, Sytnik, Veniamin, Tiunov, Mikhail, /Novosibirsk, IYF, Tkachenko, Leonid, Wildman, David, Wolff, Daniel, Zhang, Xiao-Long
• Format: Journal Article
• Language: English
• Published: United States 12.09.2011
• Subjects: ACCELERATORS; Accelerators,PHYS; ANTIPROTON BEAMS; ANTIPROTONS; APERTURES; BEAM-BEAM INTERACTIONS; ELECTRON BEAMS; ELECTRONS; ELECTROSTATICS; FERMILAB TEVATRON; INTERACTION RANGE; LENSES; LIFETIME; LUMINOSITY; MAGNETS; PARTICLE ACCELERATORS; PROTONS; TUNING
• ISSN: 1098-4402; 1098-4402

Fermilab's Tevatron is currently the world's highest energy accelerator in which tightly focused beams of 980 GeV protons and antiprotons collide at two dedicated interaction points (IPs). Both beams share the same beam pipe and magnet aperture and, in order to avoid multiple detrimental head-on collisions, the beams are placed on separated orbits everywhere except the main IPs by using high-voltage (HV) electrostatic separators. The electromagnetic beam-beam interaction at the main IPs together with the long-range interactions between separated beams adversely affect the collider performance, reducing the luminosity integral per store (period of continuous collisions) by 10-30%. Tuning the collider operation for optimal performance becomes more and more cumbersome as the beam intensities and luminosity increase. The long-range effects which (besides being nonlinear) vary from bunch to bunch are particularly hard to mitigate. A comprehensive review of the beam-beam effects in the Tevatron Collider Run II can be found in Ref. [1]. The beam-beam effects have been the dominating sources of beam loss and lifetime limitations in the Tevatron proton-antiproton collider [1]. Electron lenses were originally proposed for compensation of electromagnetic long-range and head-on beam-beam interactions of proton and antiproton beams [2]. Results of successful employment of two electron lenses built and installed in the Tevatron are reported in [3,4,5]. In this paper we present design features of the Tevatron electron lenses (TELs), discuss the generation of electron beams, describe different modes of operation and outline the technical parameters of various subsystems.