Stark broadening and shift of selected Ge II spectral lines

Abstract

We present experimental Stark widths (w) and shifts (d) of selected singly ionized germanium (Ge II) lines. The experiment is conducted in laser-induced plasma in helium atmosphere at reduced pressure. Spectra are taken side-on, in imaging mode of the CCD camera, which provides Stark shift measurement from a single image of the spectrum relying on inverse Abel transform. Stark width and shift values for 11 Ge II lines are presented. All Stark shift values are measured for the first time and also Stark widths for four Ge II lines. Our w data are compared with existing experimental and theoretical results.