Measurements of silica glass and water using a high-prssure diffractometer in J-PARC/MLF

Katayama, Yoshinori; Hattori, Takanori   ; Yagafarov, O.*; Saito, Hiroyuki; Sano, Asami   ; Suzuya, Kentaro; Chiba, Ayano*

As the first high-pressure experiments on structurally disordered materials using a new high-pressure neutron diffractometer, PLANET, installed in J-PARC/MLF, measurements of silica glass were caried out. We compressed a sample in a ZrO cube using a six-axis press and measured diffraction at pressures of 0.1 MPa, 2.3, 5.5, 7.5 and 9.9 GPa at room temperature. The size of the sample was 4.6 mm in diameter and 6.7 mm in height. The size of the incident beam was 2.5 mm in width and 4.5 mm in height. The pressure was estimated from the applied load. Vanadium sample and empty cell were also measured for the correction of the diffraction intensity. Clean diffraction patterns without diffraction lines from surrounding materials were obtained thanks to the radial collimator system. Measurements on heavy water at room temperature, 100C and 200C at 0.8 GPa were also carried out. Significant temperature dependence of diffraction pattern was observed.