Design of a pulsed-power driven platform to study photoionization fronts in the laboratory

Photoionization fronts play an important role in many astrophysical environments, including the development of galactic structure at the end of the Cosmic Dark Ages [1] and the formation of stellar-wind bubbles around O-type stars [2]. Despite their importance, predictions of photoionization front behaviour have yet to be tested in laboratory experiments [3]. We present designs for a new experimental platform for studying photoionization fronts using the MAGPIE pulsed-power facility (1 MA, 500 ns). A wire array Z-pinch will be used to produce an intense burst of X-Rays (10$^{\mathrm{4}}$ J in 20ns) which will drive a photoionization front through a target. The target, a vaporised Al wire expanded to 10$^{\mathrm{18}}$ -- 10$^{\mathrm{19}}$ cm$^{\mathrm{-3}}$, will be driven by a separate generator (10kA, 20ns). Front properties will be diagnosed using 2-color laser interferometry, Thomson scattering and X-Ray absorption spectroscopy. [1] B. E. Robertson, Nature, 2010 [2] J. Mackey, Astronomy {\&} Astrophysics, 2016 [3] R. P. Drake, The Astrophysical Journal, 2016