The upgraded Polaris powder diffractometer at the ISIS neutron source
Journal article, 2019

This paper describes the design and operation of the Polaris time-of-flight powder neutron diffractometer at the ISIS pulsed spallation neutron source, Rutherford Appleton Laboratory, UK. Following a major upgrade to the diffractometer in 2010-2011, its detector provision now comprises five large ZnS scintillator-based banks, covering an angular range of 6° ≤ 2θ ≤ 168°, with only minimal gaps between each bank. These detectors have a substantially increased solid angle coverage (ω ∼5.67 sr) compared to the previous instrument (ω ∼0.82 sr), resulting in increases in count rate of between 2× and 10×, depending on 2θ angle. The benefits arising from the high count rates achieved are illustrated using selected examples of experiments studying small sample volumes and performing rapid, time-resolved investigations. In addition, the enhanced capabilities of the diffractometer in the areas of in situ studies (which are facilitated by the installation of a novel design of radial collimator around the sample position and by a complementary programme of advanced sample environment developments) and in total scattering studies (to probe the nature of short-range atomic correlations within disordered crystalline solids) are demonstrated.

Author

R. I. Smith

ISIS Facility

S. Hull

ISIS Facility

Matthew G. Tucker

ISIS Facility

Oak Ridge National Laboratory

Helen Y. Playford

ISIS Facility

D. J. McPhail

ISIS Facility

S. P. Waller

ISIS Facility

Stefan Norberg

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Environmental Inorganic Chemistry

Review of Scientific Instruments

0034-6748 (ISSN)

Vol. 90 11 115101

Subject Categories

Accelerator Physics and Instrumentation

DOI

10.1063/1.5099568

More information

Latest update

11/14/2019