The NCNR backscattering spectrometer
The NCNR backscattering spectrometer is one of the highest intensity instruments of its kind. It enables very high energy resolution studies of the low frequency dynamics of many systems. The High Flux Backscattering Spectrometer is well-suited for investigations in soft condensed matter, chemical physics, polymer dynamics, and biology. A backscattering spectrometer is an inverse-geometry instrument in which only those neutrons with a particular final energy (2.08 meV in this case) are detected in the counting process. The motions in the sample are probed by varying the energy of the incident neutrons (by Doppler motion of the monochromator) and measuring the gain or loss in energy that they undergo in their interaction with the sample. The backscattering spectrometer at the NCNR is located on neutron guide NG2. The photograph below shows the instrument as seen from the north-east corner of the Guide Hall.