EOS with Double-shock Compression*

We present data from recent D₂ experiments where off-Hugoniot (double-shock) states were measured directly and characterized. We deduce mechanical, thermal, and transport, properties of the double-shocked material to pressures of several Mbar with reflectivity, shock velocity, and temperature data obtained from velocity interferometry and optical pyrometry. We conclude with a comparison of our findings to recent experimental work by Fernandez-Panella et al. (2019) and theoretical work by Rygg et al. (2023).