1. Temperature distribution Vertical displacement
(1)
(2)
Boundary condition
Temperature distribution
Vertical displacement
Magnetic center vertical offset ~0.3mm.
(3)

2. Causes for vertical orbit drift
Source
Time scale
Tunnel drift
Magnet alignment
Optics change
Magnet & structure thermo- expansion.
Power supplies drifts / electronic components change
Run-to-run
(3-4 months)
~1-2mm
1-2mm
~5mm
1mm
~1mm
Day-to-day
1day - mm
Fill-to-fill
1-4 hrs
~0.1mm
How to fix
Often survey in drifting areas
Modeling of the magnets displacement
(Clean leaving)
Optics modeling
Better tunnel temperature control, one save set and constant current operation.
Regular PS calibrations.
PS calibration after component change.