SPECS 2D-CCD, User Manual

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Manual V2.docx | Status 10.12.2015 | Version 1
Figure 13. Principle of operation.
5.1.1
Analyzer
The electrons for the spin detector do not travel along the center of the hemispherical
analyzer, but rather closer to the inner hemisphere. The CCD detector is located at a radius
larger than the mean radius analyzer. Because of this, the spin detector and the CCD
detector will, at any one time, detect electrons which started with different kinetic energies
at the sample. The software compensates for this effect, so that the energy scale for each
detector is correct.
5.1.2 Acceleration lens
The acceleration lens consists of sections L1, L2, L3, and a lens triplet called L4A, L5, L4B. L2
is segmented in four quadrupole segments and forms the spin deflector 1 which steers the
beam into the 90° deflector. The deflection voltages are called SpinDeflection1X and
SpinDeflection1Y or SDefl1X and SDefl1Y. The first lens in the triplet (L4A) has two apertures
L4E
L4D
L5B
L4C
Ferrum detector
L5A
Sample
Target
Coil 1
Coil 2
Y
X
Z