A small-angle neutron scattering cell for the study of supercritical fluids at elevated pressure and high temperature: A study of heavy water

Abstract

The main characteristics of a cell optimized for small-angle neutron scattering experiments on supercritical fluids are presented. The cell operates satisfactorily at pressures up to 300 bar at 400 °C and 750 bar at 90 °C. It has large apertures sealed by thick synthetic sapphire windows. The maximum forward scattering angle is 16° and the sample path length is 5.1 mm. It has been used to study scattering from supercritical heavy water close to its critical point at wave number transfers up to 0.34 Å−1.