- Library Home /
- Search Collections /
- Open Collections /
- Browse Collections /
- TRIUMF: Canada's national laboratory for particle and nuclear physics /
- Magnetic field tolerances for a six-sector 500 MeV...
Open Collections
TRIUMF: Canada's national laboratory for particle and nuclear physics
Magnetic field tolerances for a six-sector 500 MeV H‾ cyclotron Craddock, M. K. (Michael Kevin); Richardson, J. Reginald
Abstract
This report discusses the tolerances which beam dynamical requirements place on the accuracy to which the cyclotron magnet must be constructed and its magnetic field measured. The tolerance most significantly affecting manufacturing methods is probably that demanded of the spiral shape of the sectors to keep vertical focusing within acceptable limits. At large radii the precision required reaches ±0.033" and will necessitate a shimming programme subsequent to manufacture. The associated ±7 G tolerance on the field flutter should be easier to achieve. Isochronism sufficient to give 36% microscopic duty factor can be provided by a radial field gradient correct to ±2 G/ft together with 35 circular trim coils. Separated turn acceleration would require ±1 G/ft with 54 trim coils and very closely controlled dee voltage, radio frequency and magnet excitation. To avoid the poor energy resolution resulting from large radial betatron oscillations, the first harmonic field amplitude must not exceed 0.2 G; this demands 72 harmonic trim coils, ±0.14° accuracy in placing the sectors, and uniformity in their reluctance to 0.5%. Finally, to keep electric stripping of the H‾ ions within ±10% limits, the hill magnetic field must meet ±0.4% limits over the outer 20 in.
Item Metadata
Title |
Magnetic field tolerances for a six-sector 500 MeV H‾ cyclotron
|
Alternate Title |
TRIUMF brown reports TRI-67-2
|
Creator | |
Publisher |
TRIUMF
|
Date Issued |
1968-12
|
Description |
This report discusses the tolerances which beam dynamical
requirements place on the accuracy to which the cyclotron
magnet must be constructed and its magnetic field
measured. The tolerance most significantly affecting
manufacturing methods is probably that demanded of the
spiral shape of the sectors to keep vertical focusing within
acceptable limits. At large radii the precision
required reaches ±0.033" and will necessitate a shimming
programme subsequent to manufacture. The associated ±7 G
tolerance on the field flutter should be easier to achieve.
Isochronism sufficient to give 36% microscopic duty factor
can be provided by a radial field gradient correct to
±2 G/ft together with 35 circular trim coils. Separated
turn acceleration would require ±1 G/ft with 54 trim coils
and very closely controlled dee voltage, radio frequency
and magnet excitation.
To avoid the poor energy resolution resulting from large
radial betatron oscillations, the first harmonic field
amplitude must not exceed 0.2 G; this demands 72 harmonic
trim coils, ±0.14° accuracy in placing the sectors, and
uniformity in their reluctance to 0.5%. Finally, to keep
electric stripping of the H‾ ions within ±10% limits, the
hill magnetic field must meet ±0.4% limits over the outer
20 in.
|
Subject | |
Genre | |
Type | |
Language |
eng
|
Date Available |
2015-05-13
|
Provider |
Vancouver : University of British Columbia Library
|
Rights |
Attribution-NonCommercial-NoDerivs 2.5 Canada
|
DOI |
10.14288/1.0107805
|
URI | |
Affiliation | |
Peer Review Status |
Unreviewed
|
Scholarly Level |
Researcher
|
Copyright Holder |
TRIUMF
|
Rights URI | |
Aggregated Source Repository |
DSpace
|
Item Media
Item Citations and Data
Rights
Attribution-NonCommercial-NoDerivs 2.5 Canada