MULTI-MEGABAR MEASUREMENT OF THE PRINCIPAL QUASI-ISENTROPE FOR TANTALUM

Quasi-isentropic ramp-loading experiments promise accurate equation-of-state (EOS) data in the solid phase at relatively low temperatures and multi-megabar pressures. Isentropic compression experiments (ICE) using the Z Machine at Sandia as a magnetic drive have recently seen significant improvements in accuracy and pressure range, due to (1) a major refurbishment and upgrade of the accelerator, (2) the development of a stripline target configuration, and (3) new experiment design and data analysis approaches. After a brief discussion of these improvements, new data are presented for the principal quasi-isentrope of tantalum.