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

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 x 10/sup 5/ g/cm/sup 2/ sec or more at an x-ray intensity of 7.4 x 10/sup 12/ W/cm/sup 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 (rho ..delta..R) of radiative energy transport in Au is found to be 3--4 times larger than that in aluminum.