Conceptual design of hollow electron lenses for beam halo control in the Large Hadron Collider

Technical Report · Thu Jun 26 04:00:00 EDT 2014

DOI:https://doi.org/10.2172/1289781· OSTI ID:1289781

Stancari, Giulio ^[1]; Previtali, Valentina ^[1]; Valishev, Alexander ^[1]; Bruce, Roderik ^[2]; Redaelli, Stefano ^[2]; Rossi, Adriana ^[2]; Salvachua Ferrando, Belen ^[2]

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1. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
2. European Organization for Nuclear Research (CERN), Geneva (Switzerland)

Collimation with hollow electron beams is a technique for halo control in high-power hadron beams. It is based on an electron beam (possibly pulsed or modulated in intensity) guided by strong axial magnetic fields which overlaps with the circulating beam in a short section of the ring. The concept was tested experimentally at the Fermilab Tevatron collider using a hollow electron gun installed in one of the Tevatron electron lenses. We are proposing a conceptual design for applying this technique to the Large Hadron Collider at CERN. A prototype hollow electron gun for the LHC was built and tested. The expected performance of the hollow electron beam collimator was based on Tevatron experiments and on numerical tracking simulations. Halo removal rates and enhancements of halo diffusivity were estimated as a function of beam and lattice parameters. Proton beam core lifetimes and emittance growth rates were checked to ensure that undesired effects were suppressed. Hardware specifications were based on the Tevatron devices and on preliminary engineering integration studies in the LHC machine. Required resources and a possible timeline were also outlined, together with a brief discussion of alternative halo-removal schemes and of other possible uses of electron lenses to improve the performance of the LHC.

• Research Organization: Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
• Contributing Organization: European Organization for Nuclear Research (CERN), Geneva (Switzerland)
• DOE Contract Number: AC02-07CH11359
• OSTI ID: 1289781
• Report Number(s): FERMILAB-TM--2572-APC; CERN-ACC--2014-0248; 1294962
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
BEAM DYNAMICS
BEAM EMITTANCE
BEAM PROFILES
CERN LHC
COLLIMATORS
CONTROL
DESIGN
ELECTROMAGNETIC LENSES
ELECTRON BEAMS
ELECTRON GUNS
FERMILAB TEVATRON
LIFETIME
MAGNETIC FIELDS
PERFORMANCE
PROTON BEAMS
SPECIFICATIONS