Beamline Alignment Quick Reference

Back to X-Ray Microscopy

1) Select x-ray energy:
Calculate scattering angle of Si 111 for desired energy with Bragg law calculator
Drive DCM Theta to the correct Bragg angle for the desired energy, drive undulators approximately to this energy as well

NOTES:
i) If DCM theta looks low (~2-4 deg) you may need to re-set user offset (current calibrated theta offset = dial + 8.646deg)
ii) Approximate Si 111 Bragg Theta = asin(1.977084/E keV)
iii) Approximate undulator offsets are ~ desired energy +0.1 keV

2) Scan mirror piezo:
Set slits to

Slit	H Size (mm)	V Size (mm)
PBS	0.2	2
NES	2	2
BDA	2	-

scan mirror piezo +/- 1 V. Set mirror piezo to the maximum.
NOTES:
i) mirror piezo feedback should be OFF
ii) CCD shutter should be set to "manual open"

2) Scan DCM roll:
Set slits to

Slit	H Size (um)	V Size (um)
PBS	0.2	2
NES	0.2	2
BDA	0.025	-

and scan roll +/- 0.25 mrad. Set roll to maximum, but correct for back lash.

3) Scan DCM pitch:
Set slits to

Slit	H Size (um)	V Size (um)
PBS	2	2
NES	2	2
BDA	0.025	-

and scan pitch +/- 0.05 mrad. Set pitch to max.

4) Scan DCM Bragg: