The determination of laser plasma electron density by K spectra of multicharged ions

Abstract

X-ray spectroscopic methods for the determination of electron densities Ne>1020 cm-3 in plasmas with high electron temperatures (Te>or approximately=0.2 keV) are reviewed. The methods considered are based on the following measurements of: (i) relative intensities of resonance and intercombination lines in spectra of He-like ions; (ii) relative intensities of satellite lines in spectra of H-like ions; (iii) relative intensities of H-like resonance doublet components; (iv) Stark broadening of the lines of H-like ions. All these methods have been used in experiments on plasma heating by focusing a laser beam on plane massive targets containing elements with nuclear charge Z=12-19. The density distribution in the plasma was measured within the limits of Ne=1018-1021 cm-3. The results obtained by all the methods are compared and the limits of application of the methods are determined.