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The rough proposal at the moment consists of initial collision positioning of the beams under extrapolated pickup readings. Fast luminosity scans would then allow fine regulation of the crossing point.
Tune spread will over 13th order resonances which are not excited by head-on
collisions. In the SPS the beam separation was controlled to 0.3 sigma.
In the LHC would aim to measure beam position at IP to +/- 1 micron, angles
to around 2 microrad. Control luminosity to 1-2%.
Experiments can provide x,y as well as the pickups.
RF
Before collisions, some re-phasing adjustment, see here
Collimators
Adjustment of D1 collimators before collisions
Lattice Ocupoles
Off during collision, beam-beam will provide sufficient Landeau damping