Temperature measurements of shocked silica aerogel foam

K. Falk, C. A. McCoy, C. L. Fryer, C. W. Greeff, A. L. Hungerford, D. S. Montgomery, D. W. Schmidt, D. G. Sheppard, J. R. Williams, T. R. Boehly, J. F. Benage
2014 Physical Review E  
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
more » ... 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.
doi:10.1103/physreve.90.033107 pmid:25314547 fatcat:n5nrfobhqba6ngld3ziw6qp3oy