Determination of Lande gJ - factors of La I levels using laser spectroscopic methods: Complementary investigations

•New metod of Lande gJ factors measurement was used for observation of La I spectra.•New experimental gJ factors have been determined.•Hfs data for La I levels have been tested and corrected.

Laser Induced Fluorescence Spectroscopy (LIF) and Optogalvanic Spectroscopy (OG) were used for the investigation of the Zeeman hyperfine structures of 26 spectral lines of La I in the wavelength range between 569.7 and 665.4 nm. As a source of free La atoms a hollow cathode discharge lamp was used. The spectra were recorded in the presence of a magnetic field of about 800G produced by a permanent magnet for two linear polarizations of the exciting laser light. As a result of the study, we determined for the first time the Landé gJ- factors of 20 levels of La I. For several other levels the Landé gJ- factors were re-investigated and determined with higher precision.