Multiple Inner-Shell Vacancies in Laser-Irradiated Au Plasma

The fifteen spectral lines between 3 and 4 keV from a laser-irradiated Au plasma were identified by the relativistic Hartree-Fock-Slater method and were attributed to multiple inner-shell vacancies: one in the $3p_{\frac{1}{2}}$ or $3p_{\frac{3}{2}}$ shell and one or two more in the $M$ or $N$ shell. The splitting of two groups of lines was about 400 eV, the same as the spin-orbit splitting in the $3p$ shell.