Cross comparison of radial collimator components, using McStas and
contributed components. It shows that all implementations are equivalent.
The Exact_radial_coll contributed component also takes into account the absorbing
blade thickness between slits, which decreases slightly intensity.
Parameters in boldface are required;
the others are optional.
Choice of radial collimator component to test, with 1=Collimator_Radial, 2=Collimator_ROC, 3=Exact_radial_coll.