Development of a longitudinal density monitor for storage rings

Conference · Wed May 28 04:00:00 EDT 2003

OSTI ID:813389

Zolotorev, M ^[1]; Beche, J -F; Byrd, J; Datte, P; De Santis, S; Denes, P; Placidi, M; Ratti, A; Riot, V; Schoenlein, R; Turner, W

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1. LBNL Library

We report on development of a new storage ring operations tool for measurement of longitudinal beam density profile. The technique mixes synchrotron light with light from a mode locked solid-state laser oscillator in a non-linear crystal and detects the up-converted radiation with a photo-multiplier. The laser is phase locked to the storage ring RF system. The laser choices available for repetition frequency, pulse length and phase modulation give a very wide range of options for matching the bunch configuration of particular storage rings. Progress in the technology of solid-state lasers ensures this system can be made robust for routine use in storage ring operations. A very large number of important applications are possible including measurement of the fraction of untrapped particles prior to acceleration, the population of particles in the nominally unfilled RF buckets in a bunch train (''ghost bunches''), longitudinal tails, the diffusion of particles into the beam abort gap and th e normal bunch parameters of longitudinal shape and intensity. We are currently investigating application to two devices: (1) the 1.9 GeV ALS electron storage ring at LBNL with 328 RF buckets, 2ns bucket spacing, 276 nominally filled bunches, 15-30ps rms bunch length and (2) the 7 TeV LHC proton collider under construction at CERN with 35,640 RF buckets, 2.5 ns bucket spacing, 2,808 nominally filled bunches, 280-620 ps rms bunch length. A proof of principle experiment is being conducted on ALS. The results of the ALS experiment and detailed analyses of the application to LHC and its requirements are described.

• Research Organization: Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA (US)
• Sponsoring Organization: U.S. DOE. Director, Office of Science. High Energy Physics (US)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 813389
• Report Number(s): LBNL--52808
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ACCELERATORS
DIFFUSION
ELECTRONS
MODULATION
MONITORS
OSCILLATORS
PROTONS
RF STORAGE RINGS LONGITUDINAL BEAM DENSITY
RF SYSTEMS
SOLID STATE LASERS
STORAGE RINGS
SYNCHROTRONS