Observation of hydrodynamic processes of radiation-ablated plasma in a small-scale hole

In the hohlraum used in laser indirect-drive inertial confinement fusion experiments, hydrodynamic processes of radiation-ablated high-Z plasma have a great effect on laser injection efficiency, radiation uniformity and diagnosis of hohlraum radiation field from diagnostic windows (DW). To study plasma filling in the DWs, a laser-irradiated Ti disk was used to generate 2-5 keV narrow energy band X-ray as the intense backlighter source, and laser-produced X-ray in a hohlraum with low-Z foam tamper was used to heat a small-scale hole surrounded by gold wall with 150 μm in diameter and 100 μm deep. The gold plasma hydrodynamic movement in the small-scale hole was measured by an X-ray framing camera and the results are analyzed. Quantitative measurement of the plasma areal density distribution and evolution in the small-scale hole can be used to assess the effect of plasma filling on the diagnosis from the DWs.