Determining the hohlraum radiation temperature and$ M$-band fraction by using shock wave technique on SGIII-prototype laser facility

Experiments have been conducted on SGIII-prototype laser facility using tow materials Al and Ti as shock wave witness plates. The radiation temperature $^{\mbox{TR}}$ and M-band fraction fM inside a hohlraum are determined by using the observed shock velocities in Al and Ti. This is the first experimental demonstration of the proposal that $^{\mbox{TR}}$ and fM can be simultaneously determined by using shock wave technique [Y. S. Li, \textit{et a}l., Phys. Plasmas \textbf{18}, 022701 (2011)]. For the Au hohlraum used in the experiments, TR is about 160 eV and $^{\mbox{fM}}$ is around 4.3\% under a 1 ns laser pulse of 2 kJ. The results from this technique are complementary to those from the broadband soft x-ray spectrometer (SXS), and the technique can be used to determine $^{\mbox{TR}}$ and fM inside an ignition hohlraum.