A study of the hyperfine structure of Ta I lines based on Fourier transform spectra and laser-induced fluorescence

Abstract

The hyperfine structure of several spectral lines of the tantalum atom has been investigated by laser excitation in the spectral range 4180-7000 Å. We report the discovery of 14 new energy levels of even parity and 21 new energy levels of odd parity. For the new levels, besides their wave number, their total angular momentum quantum number J , their parity, as well as their magnetic dipole and electric quadrupole hyperfine interaction constants A and B were determined. We classified altogether 73 lines by means of laser spectroscopy in a hollow cathode discharge, 52 of them by laser excitation and 21 via fluorescence decay. Additionally, 120 lines, observed in high-resolution Fourier transform spectra, were classified by using their wave numbers and their characteristic hyperfine patterns.

The Role of the Hyperfine Structure for the Determination of Improved Level Energies of Ta II, Pr II and La II

“…Either laser-induced fluorescence light or the change of the discharge impedance (optogalvanic detection) was observed. Details of the experimental arrangement can be found in various publications, e.g., [1][2][3].…”