PG002 monochromator

Finally, FLEXX now comprises a double focussing PG002 monochromator (upgraded from the vertically focusing monochromator from the old FLEX).  In the horizontal plane this is part of the virtual source setup. Focusing in the vertical direction is provided entirely by the crystal optics.

This means that the full beam height is transported by a vertical neutron guide to the monochromator without elliptical compression.