Fine-structure intervals for the lowest P terms in the Cu, Zn, Ga, and Br isoelectronic sequences for Z <= 92

Spectroscopic analysis of N-intrashell transitions in Rb-like to Ni-like Yb ions

Extreme ultraviolet spectra of highly-charged ytterbium ions produced in an electron beam ion trap at the National Institute of Standards and Technology were observed with a flat-field grazing incidence spectrometer in the wavelength region of about 4 nm-20 nm. The measured spectra were interpreted through detailed analysis by collisional-radiative modeling of the non-Maxwellian EBIT plasma. Seventy-nine new spectral lines due to intrashell (Δn = 0, n = 4) electric-dipole, magnetic-dipole, and electric-quadrupole transitions were identified in Rb-like Yb33+ through Ni-like Yb42+ ions. The effects of strong configuration interaction within the n = 4 complex on the measured spectra are discussed for a number of ionization stages.

Intercombination Transitions in the n = 4 Shell of Zn-, Ga-, and Ge-Like Ions of Elements Kr through Xe

Earlier beam-foil measurements have targeted 4s-4p intercombination transitions in the Zn-, Ga- and Ge-like ions of Nb (Z=41), Mo (Z=42), Rh (Z=44), Ag (Z=47) and I (Z=53). At the time, the spectra were calibrated with literature data on prominent lines in the Cu- and Zn-like ions. Corresponding literature data on the intercombination transitions in Ga- and Ge-like ions were largely lacking, which caused some ambiguity in the line identifications. We review the (mostly computational) progress made since. We find that a consistent set of state-of-the-art computations of Ga- and Ge-like ions would be highly desirable for revisiting the beam-foil data and the former line identifications for the elements from Kr (Z=36) to Xe (Z=54). We demonstrate that the literature data for these two isoelectronic sequences are insufficient, and we contribute reference computations in the process. We discuss the option of electron beam ion trap measurements as an alternative to the earlier use of classical light sources, beam-foil interaction and laser-produced plasmas, with the example of Xe (Z=54).

New spectroscopic results in Kr VIII

New Kr VIII spectroscopic results between 280 and 2000 A using a theta-pinch and a discharge tube are presented, including one new energy level and two new classified lines. The previous analysis was also revised, and the uncertainty in the resulting level values is now <10 cm(-1).