We present recent result of equation of state (EOS) measurements of shocked silica (SiO2) aerogel foam at the OMEGA laser facility. Silica aerogel is an important low-density pressure standard used in many high energy density experiments, including the novel technique of shock and release. Due to its many applications it has been a heavily studied material and has a well known Hugoniot curve. This work then complements the velocity and pressure measurements with additional temperature data

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... ding the full EOS information within the warm dense matter regime for the temperature interval of 1 − 15 eV and shock velocities between 10 and 40 km/s corresponding to shock pressures of 0.3 − 2 Mbar. The experimental results were compared with hydrodynamic simulations and equation of state models. We found that the measured temperature was systematically lower than suggested by theoretical calculations. Simulations provide a possible explanation that the emission measured by optical pyrometry comes from a radiative precursor rather from the shock front, which could have important implications for such measurements.