The effect of hyperfine splitting on Stark broadening for three blue-green Cu i lines in laser-induced plasma

Abstract

ABSTRACT Stark effect is observed in many natural and artificial plasmas and is of great importance for diagnostic purposes. Since this effect alters profiles of spectral lines, it should be taken into account when assessing chemical composition of radiation sources, including stars. Copper is one of the elements which studies of stellar atmospheres deal with. To this end, UV and visible Cu lines are used. However, there is a lack of agreement between existing data on their Stark parameters. It is therefore of interest to obtain new experimental data on these lines and to compare them to previous results. In this work, we have estimated Stark widths and shifts for three blue-green lines at 5105.54, 5153.24, and 5218.20 Å (corresponding transitions are [3d104p] 2P° → [3d94s2] 2D and [3d104d] 2D → [3d104p] 2P°) observed in a ‘long-spark’ laser-induced plasma. For the first time, we have accurately estimated an impact of hyperfine splitting on the profile shapes of the studied lines taking also into account the isotope shifts. We have shown that both effects considerably influence shift and width of Cu i line at 5105.54 Å, and shifts of Cu i lines at 5153.24 and 5218.20 Å.