Classification of X-Ray Spectra from Laser Produced Plasmas of Atoms from Tm to Pt in the Range 6-9 Å

X-ray spectra of highly ionized tungsten and neighbouring atoms (Tm, Yb, Hf, Ta, W, Re and Pt) has been observed from laser produced plasmas in the λ = 6-9 A range. Beside the prominent lines of the Ni I-like ions, lines belonging to Co I (3 d 9 -3 d 8 4 p ), Cu I (3 d 10 4 s -3 d 9 4 s 4 p , 3 d 10 4 p -3 d 9 4 p 2 ) and Zn I-like ions (3 d 10 4 s 2 -3 d 9 4 s 2 4 p , 3 d 10 4 s 4 p -3 d 9 4 s 4 p 2 ) have been identified. Classification was based on isoelectronic sequence analysis and on comparison with ab-initio relativistic calculations. A collisional-radiative model of the Cu I-like ions in the plasma is used to show that the contribution of the 3 d 10 4 d -3 d 9 4 p 4 d and 3 d 10 4 f -3 d 9 4 f 4 p transition arrays to the 3 d -4 p spectrum is small. The importance of configuration interaction is pointed out. Computations agree with measurements within experimental uncertainty.