Sample Alignment Quick Reference

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Prior to this section make sure beamline alignment has been performed (Beamline Alignment Quick Reference)

1) Verify optic alignment
Perform CCD changeover to Coolsnap
Drive focusing optic into beam, adjust OSAX and OSAY so outgoing focused beam is not clipped and remnant central parallel beam intensity is minimized
Close NES slits to 0.1x0.1, adjust FOMX and FOMY to center optic on beam axis - outgoing wavefront clipped by slits should look symmetric around the edges
Record this as your "optic in" position, move FOMX so parallel beam is unobstructed with NES slits at 1x1 (should be ~+4000 relative move) - this is your "parallel beam" position

NOTES:
i) Central stop may be offset from the center of optic - do not simply put image of central stop in the center of the beam footprint when aligning optic

2) Mount sample
Move Objective Y to 0.0, rotate Sample Theta to 90 degrees, vent chamber
Remove old sample, slide new sample stick into machined slot, verify sample is flush with bottom of slot
Pump down chamber
View sample from top camera, roughly adjust SAMZ to put surface on marked focal plane
View sample from upstream camera, roughly adjust SAMX and SAMY to put region of interest on marked focal spot
NOTES:
i) Camera positions will not be accurate until chamber is pumped down