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Published on: May 3, 2019
Spectrum and Energy Levels of Neutral Thulium
J Sugar1, W F Meggers1, P Camus2
1Institute for Basic Standards, National Bureau of Standards, Washington, D.C. 20234.
Abstract:
A new set of measurements of the spectrum of neutral thulium covering the range of 2513 Å to 11750 Å is given. The light source utilized for the observations was a microwave-excited thuliumiodide lamp. Second spectrum lines were recognized by comparing the output of this lamp with that of a 6A sliding spark. The results of Zeeman effect studies of these lines are included. Analysis of these new data led to the discovery of 348 new energy levels and provided revised values for the 142 already published. Measured Landé g factors are given for most of the levels.
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