Development of 0.5 mm gauge size radial collimators for high-pressure neutron diffraction experiments at PLANET in J-PARC

Hydrogen bond symmetrisation in D2O ice observed by neutron diffraction

“…More than 10 independent loadings for the D 2 O sample (99.9 %, MagniSolv TM ) into nano-polycrystalline diamond anvil cell (NPDAC) were conducted, and in total 7 runs (#1-#7) had sufficient quality for detailed analyses. In each run, we varied the culet size and shape of anvils, the material and thickness of the gasket, diffraction geometry and neutron collimation using fine radial collimators 37 (see details in Supplementary Table 1 ). Except for run #2, we used cup-shaped culets to reduce unwanted scattering from the diamond anvils and to reduce deviatoric stress by relatively uniform compression compared to the case using the flat anvils 14 , 38 .…”

“…3 He gas detectors positioned in a pair of banks at 2 θ = 90° (coverage: 2 θ = 90 ± 11.3°, χ = 0 ± 34.6°) 28 . To reduce the background, radial collimators with a gauge length of 1.1 mm and of 0.5 mm for runs #1-#3 and runs #4-#7, respectively 37 . In run #6, the compression axis of the NPDAC was perpendicular to the incident beam, with incoming neutrons travelling through the gasket to reach the sample and the scattered neutrons also travelling through the gasket (“through gasket geometry”).…”