This paper describes a new method of compressing materials up to pressures of several megabars. A high-intensity magnetic field, obtained by magnetic flux compression, is used to compress a sample contained in a metallic tube. The compression of the sample is slow enough to avoid the generation of shock waves which allows the process to be isentropic. This paper describes the apparatus and several experiments with Lucite samples. Evidence that Lucite was isentropically compressed to a specific volume of about 0.25 is included. The pressure reached is estimated to be ~4 Mbar.

No abstract

Tlfc is i fKfmt .f 1 pftr mtnki br (ttH-• itiijl-••? te wfc tafa. HBoli-. •• Htpmt «•*-**«» *e-" nil m W art » wfiifctrf lifcir *i friM»in «r*ci Knnmi «F ns rawai s unfa ^

A linear electric motor has been built to study hydrodynamic instabilities at the interface between fluids subjected to acceleration. The facility is powered by 16 independent capacitor banks to provide arbitrary acceleration profiles up to 1000 times earth’s gravity. Electrical measurements include the current, magnetic field, acceleration, and projectile trajectory. The instability is observed with flash shadowgraphy. The shot turnaround time is <15 min and over 100 shots can be taken before replacing the armature and rails.

This paper describes an apparatus that can be used to study the Raman and fluorescence spectra of liquids and solids up to pressures above 80 kilobar and in the temperature range between about 100 and 500 K. Basically, the pressure is produced by two opposed Bridgman anvils, whereby at least one anvil is made out of transparent sapphire material. This allows back scattered Raman measurements from a sample which is in the same environment as a small ruby crystal. The fluorescence lines of the ruby crystal at 14432 and 14404 cm−1 are frequency shifted by pressure and temperature and this effect is used to accurately measure the pressure in the cell. Raman spectra of water in the liquid, ice VI, VII, and VIII phases are given here to illustrate the capability of this apparatus.