A laboratory photoionized plasma experiment driven by a long duration x-ray flux*

Many astrophysical environments such as x-ray binaries, active galactic nuclei, and accretion disks of compact objects include photoionized plasmas. Detailed x-ray spectral observations performed with the Chandra and XMM-Newton orbiting telescopes provide critical information on the state of these plasmas. However, the complexity of the astrophysical environment makes the spectral analysis challenging, and thus laboratory experiments are important to test and establish what physics models are needed to describe the plasma.¹ An experiment is being developed at the OMEGA EP laser in which a tamped Si sample is driven by a three-hohlraum source that produces a 30ns-duration, broad band x-ray flux with a radiation temperature of 90eV.² The photoionized plasma is diagnosed with L-shell emission and K-shell absorption spectroscopy. The latter is afforded by using a laser beam to drive a separate short-duration source of backlighting photons. Probing the Si plasma at different times provides a test of the photoionization equilibrium condition in the plasma.¹R. C. Mancini et al, Phys. Plasmas 16, 041001 (2009); ²D. Martinez, 2017 Annual OLUG Workshop, in preparation for publication.