Small beam - Post Vert A mirror

Post Vertical mirror coordinates (Branch A) for small beam sizes

March 2022, by Igor Pis

Grating Z (d ± 0.2 mm)  Z (No. Screw revolutions) Pitch (μm)
See Note 2
 "Large beam" < 55 mm 2 to 4 CCW from "0" pos   See Note 3
SG2, SG3, SG1 standard position 51 mm 2 CCW from "0" pos -8500 Standard position from Aug 2022
SG2, SG3, SG1 55.1 mm "0" (-7150)
-8099 (-0.5)
The Pitch values changed in July 2022
SG2, SG3
small beam
59.2 mm 2 CW from "0" pos. -6350  
SG4 standard 61.1 mm 3 CW from "0" pos -6050  
small beam (ARPES)
69.2 mm 7 CW from "0" pos -5200 See Note 1

Note 1: To have enough space for moving the mirror down, the top cover of the optical bench under the pneumatic valve of the mirror chamber must be removed.
Note 2: The Pitch values are approxiamte, they should be veryfied for XPS/ARPES every time the Z position is changed.
Note 3: When Z is moved up (d below 55 mm), the beam is broadening in vertical direction, the XPS signal increases, but the resolution decreases (not very much for SG2, but it can quite a lot for SG3 at high photon energies and for SG4 at all energies. The resolution(Au4f peak width) should be checked when the Z is moved here.

Z position screw
Last Updated on Tuesday, 09 August 2022 16:38