Equation of state measurements of hydrogen isotopes on Nova

Abstract
The Nova laser [E. M. Campbell, Laser Part. Beams 9, 209 (1991)] was used to shock-compress liquid deuterium and obtain new principal Hugoniot measurements of density and pressure between 0.3 and 2.1 Mbar. In this pressure-density region, deuterium is predicted to transform from a molecular insulating fluid to an atomic conducting fluid. Nova data show a rapid increase in density from 0.6 g/cc at 0.3 Mbar, to 1 g/cc at 0.6 Mbar, suggestive of such a transition. The observed sixfold compression near 1 Mbar is larger than predicted by many widely used equation of state models.