Optical Radiation Properties of NaCl Crystal under Shock Compression

The optical absorptances of crystal NaCl under shock compression from 40 GPa to 70 GPa were measured using optical radiation technique. Comparing with Kormer's results, our results are almost as ten times as Kormer's results when shock pressure is about 60 GPa. The results show that the possible reason for causing this difference is that the time resolution of experimental record system used by Kormer was not fast enough. The changing of free-carrier mobility with shock temperature was calculated by using the experimental data. The results show that our results have a good agreement with Ziman's theoretical results. The disagreement existed in Kormer's experimental results and Ziman's theoretical results all the time was resolved.