Speaker
Joachim Wuttke
(JCNS at MLZ)
Description
SPHERES is a third-generation backscattering spectrometer with phase-transform chopper, located at a cold-neutron guide of FRM II, and in routine operation since 2007. For technical details, see [1,2,3]. In this talk, for a unique assembly of experts, I will not so much celebrate what we have achieved, but rather discuss the subtle difficulties that limit the accuracy of this fine experimental method. I will also highlight recent progress in modelling beam deflection by thick mosaic crystals [4].
[1] Wuttke et al, SPHERES, Jülich's high-flux neutron backscattering spectrometer at FRM II.
Rev. Sci. Instrum. 83, 075109 (2012).
[2] Wuttke & Zamponi, Simulation-guided optimization of small-angle analyzer geometry in the neutron backscattering spectrometer SPHERES. Rev. Sci. Instrum. 84, 115108 (2013).
[3] Khaneft et al, Upgrading the Neutron Backscattering Spectrometer SPHERES. II. Faster
Phase-Transform Chopper with Wider Deflector Mosaic. In preparation.
[4] Wuttke: Multiple Bragg reflection by a thick mosaic crystal.
Acta Cryst. A 70, 429-440 (2014).
Primary author
Joachim Wuttke
(JCNS at MLZ)
Co-authors
Marina Khaneft
(Forschungszentrum Jülich)
Michaela Zamponi
(Forschungszentrum Jülich)