Time-resolved x-ray spectrometer for opacity study through Z-pinch dynamic Hohlraum radiation.

A new time-resolved x-ray spectrometer is currently being developed in China's 10-MA facility, which is used for the Z-pinch dynamic Hohlraum radiation-driven opacity experiments. The spectrometer utilizes a six-slits imaging system, generating six frames of soft x-ray spectral images on time-resolved gold-coated MCP detectors after diffraction of a convex cylindrical KAP crystal. The gating time of the system is ∼1.1 ns, which greatly suppresses the background noise generated from the Z-pinch high-energy radiation beyond the backlighting moment. We present the time-resolved and time-integrated absorption x-ray spectral of radiation heated Al + Fe mixed plasma. By comparing the experimental x-ray transmission with the calculated transmission of Al plasma, we suggest that the radiative heated Al/Fe plasma achieves a temperature of ∼112 eV and an ion density of 1.1 × 1021 cm-3.