Beamline and analyzer slits

Analyzer slit

Before starting the measurement select a proper analyzer slit (black knob on the analyzer).

Back side of the analyzer and black knob for slit selection. Current reading is 100.

Narrow slit: + better k-resolution perpendicular to the slit - more difficult to focus and less counts. Curved slit: + flat Fermi level and constant energy surfaces - makes a curved cut in k-space Straight slit: + makes a straight cut in k-space - curved Fermi level (energies need to be corrected programmatically).

We usually start with 400.

Table can be also found on the wall behind the monitors

Beamline exit slit

Beamline (BL) exit slit vertical width is controlled manually with a knob behind the electronics rack.

The BL slit knob. Reading is 13.95.

With a smaller slit you improve energy resolution, but get less counts.

Plateau area (~140um) is a good starting point.

BL exit slit calibration curve. Plateau area is around 12+-1.

Beamline resolution for a given BL exit slit and photon energy can be estimated using an Igor script provided below (beamline parameters correspond to 1^2):

Change only the 2 parameters on top.

Last updated

Was this helpful?