The upgrade of the cold neutron triple-axis spectrometer FLEXX is described.
We discuss the characterisation of the gains from the new primary spectrometer,
including a larger guide and double focussing monochromator, and present
measurements of the energy and momentum resolution and of the neutron flux of
the instrument. We found an order of magnitude gain in intensity (at the cost
of coarser momentum resolution), and that the incoherent elastic energy widths
are measurably narrower than before the upgrade. The much improved count rate
should allow the use of smaller single crystals samples and thus enable the
upgraded FLEXX spectrometer to continue making leading edge measurements.Comment: 8 pages, 7 figures, 5 table