Finding of previously unknown energy levels using Fourier-transform and laser spectroscopy

Abstract

In this paper several possibilities of how to find previously unknown energy levels from highresolution Fourier-transform or laser-generated spectra are discussed. As examples we use levels of neutral Ta, Pr and La. The following methods are used: analysis of Fourier-transform emission spectra, laser-excitation of unclassified spectral lines, analysis of the hyperfine structure of unclassified lines. The discovery of two new La I energy levels is reported.

Progress in Finding New Energy Levels Using Laser Spectroscopy

“…The example given above tells us which tools are necessary for the classification of a line and for the characterization of a new energy level: All these tools are now available using the program "Elements", described in [14,15]. In contrast to previous work a long time ago [16], now all the needed tools are available during the performance of the experiment, and usually immediately after finding a LIF line and recording of the hf pattern the new level can be found.…”

Experimental Investigation of the Hyperfine Structure of Neutral Praseodymium Spectral Lines and Discovery of New Energy Levels

“…in ref. (Windholz 2016). But here we obtained only one LIF line, so this scenario cannot be resolved.…”

Investigation of the Hyperfine Structure of Atomic Niobium (Nb I) Spectral Lines Based on the Lower Energy Levels at 22936, 23010, and 23048 cm<sup>-1</sup>

“…During the present investigations, we calculated possible transition wavelengths between the lower even levels of interest and upper odd energy levels in the wavelength range of our lasers using the program "Elements" [24] [25]. Then we set the laser wavelength to such a calculated value and searched for a LIF The hf structure constants A of these three even levels are given in ref.…”