Production of photoionized plasmas in the laboratory with x-ray line radiation.

In this paper we report the experimental implementation of a theoretically proposed technique for creating a photoionized plasma in the laboratory using x-ray line radiation. Using a Sn laser plasma to irradiate an Ar gas target, the photoionization parameter, ξ=4πF/N_{e}, reached values of order 50ergcms^{-1}, where F is the radiation flux in ergcm^{-2}s^{-1}. The significance of this is that this technique allows us to mimic effective spectral radiation temperatures in excess of 1 keV. We show that our plasma starts to be collisionally dominated before the peak of the x-ray drive. However, the technique is extendable to higher-energy laser systems to create plasmas with parameters relevant to benchmarking codes used to model astrophysical objects.