|Science with Neutrons|
Neutron backscattering is one of several inelastic neutron scattering techniques. Backscattering from monochromator and analyzer crystals is used to achieve an energy resolution in the order of μeV. Neutron backscattering experiments are performed to study atomic or molecular motion on a nanosecond time scale.
Neutron backscattering was proposed by Heinz Maier-Leibnitz in 1966, and realized by some of his students in a test setup at the research reactor FRM I in Garching bei München, Germany.  Following this successful demonstration of principle, permanent spectrometers were built at Forschungszentrum Jülich and at the Institut Laue-Langevin (ILL). Later instruments brought an extension of the accessible momentum transfer range (IN13 at ILL), the introduction of focussing optics (IN16 at ILL), and a further increase of intensity by a compact design with a phase-space transform chopper (HFBS at NIST, SPHERES at FRM II).
List of backscattering spectrometers 
Operational backscattering spectrometers at reactors:
- IN10 at the Institut Laue-Langevin
- IN13 at the Institut Laue-Langevin
- IN16 at the Institut Laue-Langevin
- High flux backscattering spectrometer (HFBS) at NIST Center for Neutron Research
- SPHERES, an instrument of Forschungszentrum Jülich at FRM II.
Inverse geometry spectrometers at spallation sources:
- IRIS at ISIS at Rutherford-Appleton
- OSIRIS at ISIS at Rutherford-Appleton
- BASIS at SNS
- MARS at Paul Scherrer Institute
- the first backscattering spectrometer was a temporary setup at FRM I
- backscattering spectrometer BSS (also called PI) at the DIDO reactor of the Forschungszentrum Jülich (decommissioned)
- H. Maier-Leibnitz: Grundlagen für die Beurteilung von Intensitäts- und Genauigkeitsfragen bei Neutronenstreumessungen, Nukleonik 8, 61 (1966).
- B. Alefeld, M. Birr, A. Heidemann, Naturwissenschaften 56, 410 (1969).
- A. Meyer, R. M. Dimeo, P. M. Gehring, D. A. Neumann: The high-flux backscattering spectrometer at the NIST Center. Rev. Sci. Instrum. 74, 2759 (2003).
- J. Wuttke et al.: SPHERES, Jülich's high-flux neutron backscattering spectrometer at FRM II. Rev. Sci. Instrum. 83, 075109 (2012).
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