Extreme Ultraviolet Emission from Multi-Charged State Ions in Potassium Plasmas

This chapter discusses the observation of intense XUV emission generated from a hollow cathode micro-discharge source. The emission in the 40 nm XUV spectral region has been characterized from capillary discharge and laser-produced plasmas containing potassium ions with time-averaged electron temperatures of 12 eV and electron densities of 1020 cm⁻³. Atomic structure calculations with the Cowan code together with available spectral data were used to generate theoretical spectra to compare with the observed emission.