|ATLAS solenoid||Magnet length ~ 5.3 m. Max. field 2 T.
Integrated field ~ 12 T.m
Max. radial field 5 e-4 T
|Negligible||Can be neglected (1 microrad from crossing angle at 450 GeV)||Bring on and leave on after prefunctory checks at 450 GeV|
|ATLAS toroid||No effect on beam||As required by Atlas.|
Central field 0.5 T
Max Radial field 20 e-4 T
|"The maximum field is ~ 0.5 T and it can be neglected."||
Orbit kick from crossing angle at 450 GeV about 1 microrad - neglectable.
Need radial field distribution to be sure but integrated field strength likely to be negligible. (12 m x 20 Gauss gives 16 microrad at 450 GeV).
|Bring on and leave on after prefunctory checks at 450 GeV. Don't worry about polarity changes.|
|ALICE dipole spectrometer
field direction H
|B.dl ~ 3 T.m ~ 130 microrad at 7 TeV
|Dedicated commissioning at 450 GeV and in ramp.|
Magnetic length ~ 13.2 m
|At 450 GeV:
delta cminus ~ -5i e-3 compared with tolerance of 0.03. Contribution relevant when solenoid is at full field at injection.
With crossing angle on - vertical kick of ~ 5 microrad
Integrated Bdl from radial field - negligible
|Measure and correct coupling at 450 GeV. Turn off for first ramp attempts - want to minimise effect of coupling on tune measurement. Check orbit when we bring on crossing angles.|
|B.dl ~ 4.2 T.m ~ 180 microrad at 7 TeV||
|Dedicated commissioning at 450 GeV and in ramp. Have to repeat for operation with crossing angle and on change of polarity.|
ML November 2007
 Main reference "The effects of solenoids and dipole magnets of the LHC experiments", W. Herr, Chamonix 2006