Reduction of data from inverted-geometry time-of-flight instruments

Abstract

The validity of differing prescriptions for the reduction of data collected on inverted-geometry time-of-flight instruments has been investigated by means of Monte-Carlo ray-tracing simulations for a virtual instrument closely resembling OSIRIS at the ISIS facility and experimental measurements on the newly commissioned instrument, MARS at SINQ, PSI. In both cases, the prescription recently set out by Dorner [Bruno Dorner, J. Neutron Res. 13, 267–274 (2005)] yields the correct scattering function.

Keywords:

• Data reduction
• Backscattering

Acknowledgements

We thank Dr Franz Demmel for valuable information relating to the IRIS and OSIRIS instruments, situated at ISIS. From our correspondence with Dr Demmel, we can confirm that the way in which raw IRIS data are treated is mathematically equivalent to the prescription of Dorner. We are also very grateful to Professor Oliver Waldmann for providing the sample of deuterated Mn₁₂.