Soft x-ray spectral analysis of samarium plasmas produced by solid-state laser pulses

XUV spectra of 150 ps laser-produced samarium(Sm) plasmas in the 1.8–10 nm wavelength region, where Δn = 1, n = 4 − n = 5 and Δn = 0, n = 4 − n = 4 transitions dominate the observed emission, were investigated experimentally and theoretically. Ab initio calculations using the flexible atomic code, as well as consideration of isoelectronictrends, are all employed to identify a number of new features in spectra from Sm16+ to Sm34+. The results show that Δn = 0, n = 4 − n = 4 emission from highly charged ionsmerge to form an intense unresolved transition arrays in the 7.5 nm region and Δn = 1, n = 4 − n = 5 resonance transitions contribute in the 3–7 nm region of the Sm spectrum. In addition, a number of strong individual lines at shorter wavelengths are seen to arise from Cu- and Zn-like ions and a number of new assignments are made for Zn-like Sm32+.