Aerogel*

The thermodynamic behavior of shock-compressed SiO₂ was studied over a broad density and temperature range using low-density foams. Temperature and reflectance measurements were performed on single-shocked SiO₂ at initial densities of 2.65 (a‑quartz), 2.2 (fused silica), 0.3 (silica aerogel), 0.2, and 0.11 g/cm³. Thermodynamic derivatives are calculated across P–T phase space using the SiO₂ Hugoniot measurements combined with other experimental data sets. This work extends the capability of SiO₂ as a thermodynamic calibrant for high-energy-density physics experiments.