The figure on the left shows the measured neutron intensity (neutrons per second) with all choppers running at
20000 rpm, as a function of neutron wavelength and resolution mode.
The sharp dips in the beam intensity at 3.35 Å and 6.70 Å are respectively due to (004) and (002) Bragg
reflections in the pyrolytic graphite filter.
The graphite filter is used to eliminate high energy neutrons (for a detailed explanation, please look at the
reference The optical filter of the disk chopper spectrometer at NIST
JRD Copley and JC Cook (2000) Physica B 283 386-388).
Click here to get
an interactive graphical interface