Damping the transverse resistive wall instability in the AGS Booster

Conference · Sun Jan 01 04:00:00 EST 1989

OSTI ID:5609998

Raka, E ^[1]

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1. Brookhaven National Lab., Upton, NY (USA)

A transverse bunch-to-bunch feedback system will be installed on the AGS Booster to suppress coherent coupled bunch oscillations driven by the resistive wall impedance of the vacuum chamber when accelerating high intensity proton beams (circulating currents > 3 amp). It is possible to estimate the expected growth rate of the instability by scaling from the machine parameters and measurements made on the AGS. An upper limit of 1.5 {times} 10{sup 3} sec{sup {minus}1} at 1.5 GeV kinetic energy with {Chi} = 0 and 0.5 {times} 10{sup 13} protons/bunch is obtained for the vertical plane. The position signal of each bunch (h = 3), at two locations separated by one quarter of a betatron wavelength, will be integrated, digitized and stored in a memory whose clock is synchronized with the acceleration frequency. This pair of inputs will be used in conjunction with look up tales, which will be related to a given range of the tune Q, to generate the proper correction amplitude. This will then be D/A converted, amplified and applied to 50{Omega} traveling wave kickers. The overall time delay will be adjusted to equal or revolution periods in order to permit the necessary digital signal processing (T{sub o} = 0.73 {mu}s at {gamma} = 2.6). An analysis of the performance of this and similar systems for within the bunch modes m = 0, 1 and both zero and non-zero head tail phase shift {Chi} will be presented. 4 refs., 1 fig.

• Research Organization: Brookhaven National Lab., Upton, NY (USA)
• Sponsoring Organization: DOE/ER
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 5609998
• Report Number(s): BNL-43275; CONF-890803--31; ON: DE90001324
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
430400* -- Particle Accelerators-- Storage Rings
ACCELERATORS
BEAM BUNCHING
BEAM DYNAMICS
BEAMS
BETATRON OSCILLATIONS
BROOKHAVEN AGS
CYCLIC ACCELERATORS
DAMPING
ELECTRIC IMPEDANCE
ELECTRICAL EQUIPMENT
ELECTROMAGNETS
EQUIPMENT
IMPEDANCE
INSTABILITY
KICKER MAGNETS
LANDAU DAMPING
MAGNETS
NUCLEON BEAMS
OSCILLATIONS
PARTICLE BEAMS
PARTICLE BOOSTERS
PROTON BEAMS
SYNCHROTRONS