Feasibility study of neutron diffraction measurements of silica glass under high pressure

Katayama, Yoshinori; Yagafarov, O.; Machida, Akihiko; Hattori, Takanori   ; Sano, Asami   ; Komatsu, Kazuki*; Otomo, Toshiya*

To test feasibility of neutron diffraction measurements of glass at high pressures up to several GPa, a sample of silica glass in a Paris-Edinburgh type high-pressure apparatus was measured at ambient conditions using a total scattering spectrometer, NOVA, at the Japan Proton Accelerator Complex (J-PARC). The sample has a shape of double convex lens, 6 mm in diameter, 4.4 mm in thickness. It was surrounded by a ring-shape gasket made of TiZr alloy and two anviles made of tungsten carbide. The incident neutron beam passed through a anvil and the diffracted beam passed through the gasket. The data acquisition time was about 20 hours. A vanadium sample and the empty gasket were also measured as references. A clear oscillation was observed in the intensity as a function of wave number.