SIKA - the cold-neutron triple-axis spectrometer with multiplexing analyzer at Bragg Institute
Asia - Oceania Neutron Scattering Association
SIKA is a high-flux cold-neutron triple-axis spectrometer funded by Ministry of Science and Technology of Taiwan and currently being operated by National Synchrotron Radiation Research Center. It locates at the OPAL reactor face at the Australian Nuclear Science and Technology Organisation (ANSTO). Its incident energy ranges from 2.5meV to 30meV with the highest flux at ~8meV. With an advanced design, SIKA is equipped with an analyzer array of 13 PG(002) blades (Fig. 1), a multi-wire detector, and a separate diffraction detector. Such a design allows SIKA to run in a traditional step-by-step mode or in various mapping (or dispersive) modes by changing the configuration of analyzers and detectors. Several typical mapping modes are analyzed and simulated using Monte Carlo ray-tracing package SIMRES of RESTRAX.  The performance of different mapping modes are demonstrated and evaluated, providing the dispersion relations of these operation modes as references for experimental studies. In hotcommissioning, a multiplexing mode with constant Ef was used to measure the phonon dispersion in a Pb single crystal. The simulation and experiment results demonstrate the flexibility and fast data-collecting potential of SIKA as a next generation cold neutron triple-axis spectrometer.
OPAL Reactor, Spectrometers, Diffraction, Cold neutrons, Simulation, Measuring instruments
Deng, G., McIntyre, G. J., Wu, C.-M., Gardner, J., Vorderwisch, P., & Li, W.-H. (2015). SIKA - the cold-neutron triple-axis spectrometer with multiplexing analyzer at Bragg Institute. Paper presented at 2nd Asia Oceania Conference on Neutron Scattering (AOCNS 2015), Novotel, Manly Pacific, Sydney, Australia, 19-23 July 2015.