Measurements and radiation transport of emitted and absorbed spectral lines within an expanded, dense aluminum plasma

Emission and absorption lines have been measured within an expanded, dense aluminum plasma plume produced by electron beam isochoric heating of 100-um-thick aluminum foils. The intense, monochromatic electron beam (20 MeV, 1.45 kA, 80-ns FWHM) deposits approximately 5 J in a sub-1-mm FWHM spot, heating and subsequently expanding the material through the warm dense plasma phase [1]. A spectroscopic-quality radiation transport model [2] has been developed using inputs from a radiation-hydrodynamics code [3] along with the LANL suite of atomic physics codes [4] to provide a complete simulation capability for matching the experimental spectra. The resulting model has been benchmarked by visible interferometer measurements. New simulations predicting the EUV spectrum (< 200 nm) of the dense aluminum plasma plume are presented, along with the design and current status of a grazing-incidence EUV spectrometer that will be deployed to make the experimental measurements. A comparison between aluminum Sesame [5] EOS 3715 and 3720 for the radiation-hydrodynamics model is also discussed.

[1] N. B. Ramey et al., Phys. Plasmas 28, 033301 (2021).

[2] P. Hakel, Comp. Phys. Commun. 207, 415 (2016).

[3] G. B. Zimmerman and W. L. Kruer, Comments Plasma Phys. Controlled Fusion 2, 51 (1975).

[4] C. J. Fontes et al., J. Phys. B 48, 144014 (2015).

[5] SESAME Library, Report No. UCID-118574-82-2 (Lawrence Livermore National Laboratory, 1982).