Experimental evidence of ionization burnthrough and absorption resonance in radiative energy transport in hot dense matter

Abstract

Radiative energy transport in hot dense matter has been investigated in the sub-keV region. In a medium-Z element (aluminum), ionization burn-through has been observed. Burn-through speed is estimated to be 6\ifmmode\times\else\texttimes\fi{}${10}^{5}$ g/${\mathrm{cm}}^{2}$ sec or more at an x-ray intensity of 7.4\ifmmode\times\else\texttimes\fi{}${10}^{12}$ W/${\mathrm{cm}}^{2}$. At a high Z (gold), the spectral structure of transmitted x rays indicates the formation of an x-ray heat conduction band via absorption resonance. Penetration depth (\ensuremath{\rho} \ensuremath{\Delta}R) of radiative energy transport in Au is found to be 3--4 times larger than that in aluminum.