CERN Accelerating science

Article
Report number	SLAC-PUB-11758
Title	High-Precision Resonant Cavity Beam Position, Emittance and Third-Moment Monitors
Author(s)	Barov, Nikolai ; Kim, Jin-Soo ; Miller, Roger H ; Nantista, Christopher D ; Weidemann, A W
Affiliation	(Far-Tech, Inc., San Diego, California) ; (SLAC)
Publication	2005
Imprint	May 2005
Number of pages	3
In:	21st IEEE Particle Accelerator Conference, Knoxville, TN, USA, 16 - 20 May 2005, pp.4311
Subject category	Accelerators and Storage Rings
Abstract	Linear colliders and FEL facilities need fast, nondestructive beam position and profile monitors to facilitate machine tune-up, and for use with feedback control. FAR-TECH, Inc. is developing a resonant cavity diagnostic to simultaneously measure the dipole, quadrupole and sextupole moments of the beam distribution. Measurements of dipole and quadrupole moments at multiple locations yield information about beam orbit and emittance. The sextupole moment can reveal information about beam asymmetry which is useful in diagnosing beam tail deflections caused by short range dipole wakefields. In addition to the resonance enhancement of a single-cell cavity, use of a multi-cell standign-wave structure further enhances signal strength and improves the resolution of the device. An estimated rms beam size resolution is sub micro-meters and beam position is sub nano-meter.