Spectral line classification of the thulium element in between 3500 cm-1 - 10000 cm-1 and hyperfine structure investigation

The aim of this study is to classify atomic and single ionized state of thulium (Tm) element in 3500 cm-1 -10000 cm-1 wavenumber range and to determine magnetic dipole hyperfine constants of the fine structure energy levels of Tm atom in this spectral region experimentally. The spectra of Tm element were obtained separately using argon and neon inert gases with Fourier Transform (FT) spectroscopy method in near and mid-infrared regions. 1148 spectral lines were analyzed using all known experimental fine structure energy levels of Tm. Among these lines, 719 lines were classified as atomic thulium (Tm I) transitions 625 of which were revealed for the first time in this study and 72 lines were classified as single ionized state of thulium (Tm II) transitions. 356 new lines were determined as Tm I or Tm II. As a result of the analysis of spectral transitions, magnetic dipole hyperfine constant A of 13 fine structure levels, have been obtained for the first time in this study experimentally. In addition, the values of two magnetic dipole hyperfine constants, which existed in the literature before this study have been revised.