Energy shift of the Lβ2 line as an ionization diagnostic for the dense plasma in the PFRP

On modest ionization, the change in the photon energies of characteristic K- and L-lines from high-Z (Z∼75) ions can be used as an ionization diagnostic (Słabkowska et al., 2014). Indeed, the line shape of the Lβ2 line in a spatially resolved but time-averaged L-shell spectrum from a tungsten Plasma Filled Rod Pinch plasma suggested ionization states up to +28W. Here the Lβ2 line is measured with nanosecond time resolution to determine the plasma's ionization as it varies in time. Together with the plasma temperature from the black-body radiation and the pressure from the expansion history, such a measurement could eventually determine the plasma's equation of state.