Time-resolved emission spectroscopy of transparent and nontransparent materials.

Time-resolved emission spectroscopy with pulsed excitation has been used to observe spectral changes of shocked transparent single crystals and nontransparent materials. For transparent single crystals, drastic spectral changes near the HEL are observed and Us-Up relations can be determined. As the shock pressure is increased in the plastic region, however, the emission intensity decreases rapidly, probably because plastic deformation develops with pressure. For nontransparent materials, measurements of emission spectra under shock compression appears more difficult than transparent materials. Results on powder materials will be presented.