Optional Collimator

Upstream of the monochromator, FLEXX now has optional collimator inserts, which can slide horizontally into the guide. By collimating the neutrons before the monochromator we can trade off Q-resolution versus neutron flux, depending on the requirements of the individual experiment. Before the collimator changer, a virtual source is placed.

The horizontal virtual source coupled with an elliptical guide section and the horizontally-focussing monochromator allows for an optimal flux at the sample position as well as optimal beam monochromaticity.