New magnet pole shape for isochronous cyclotrons

Journal Article · Mon Jun 01 00:00:00 EDT 1981 · IEEE Trans. Nucl. Sci.; (United States)

DOI:https://doi.org/10.1109/TNS.1981.4331600· OSTI ID:6332984

Thorn, C E; Chasman, C; Baltz, A J

A new design has been developed for shaping pole tips to produce the radially increasing fields required for isochronous cyclotrons. The conventional solid hillpoles are replaced by poles mounted over a small secondary gap which tapers radially from maximum at the magnet edge to zero near the center. Field measurements with a model magnet and calculations with the code TRIM show an increase in field at the edge of the magnet without the usual corresponding large increase in fringing, and a radial field shape more nearly field independent than for conventional hills. The flying hills have several advantages for variable energy multiparticle cyclotrons: (1) a large reduction in the power dissipated by isochronizing trim coils; (2) a more constant shape and magnitude flutter factor, eliminating flutter coils and increasing the operating range; and (3) a sharper fall-off of the fringe field, simplifying beam extraction. 6 figures.

• Research Organization: Brookhaven National Lab. (BNL), Upton, NY (United States)
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 6332984
• Journal Information: IEEE Trans. Nucl. Sci.; (United States), Vol. NS-28:3
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ISOCHRONOUS CYCLOTRONS
MAGNETIC FIELDS
MAGNETS
COMPUTERIZED SIMULATION
GEOMETRY
MAGNET COILS
SHAPE
SPECIFICATIONS
STABILITY
ACCELERATORS
CYCLIC ACCELERATORS
CYCLOTRONS
ELECTRIC COILS
ELECTRICAL EQUIPMENT
EQUIPMENT
MATHEMATICS
SIMULATION
430200* - Particle Accelerators- Beam Dynamics
Field Calculations
& Ion Optics