New electron levels and classified lines in Pr II from hyperfine structure measurements

In this work results of the laser-induced fluorescence measurements of the hyperfine structure for 22 electronic levels belonging to the odd configurations of lanthanum ion La II, hitherto not investigated or investigated with lower precision, are presented. The results obtained have been applied in semi-empirical calculations of fine and hyperfine structure radial parameters, performed within the basis of 42 configurations.

Section: Methodsmentioning

confidence: 99%

Hyperfine structure in La II odd configuration levels

Furmann¹,

Ruczkowski²,

Stefańska³

et al. 2008

“…Along with the laserinduced fluorescence signal, transmission variations of a highfinesse Fabry-Perot interferometer (FSR = 1500 MHz), used as a frequency marker, were recorded (the resulting regular comb of transmission peaks was used for generation of the frequency scale for the spectrum). The experimental setup applied is a rather typical one and was successfully used earlier in similar investigations [7,8,[24][25][26][27][28][29].…”

Section: Methodsmentioning

confidence: 99%

“…Fourier spectra). In our work concerning praseodymium ion [26,29], a method including additional LIF measurements of fluorescence channels of the line investigated (and thus involving the same upper level) was applied. However, this method can only be used in the cases when at least some of the fluorescence channels lie in the spectral region covered by available tunable lasers.…”

Section: Methodsmentioning

confidence: 99%

Hyperfine structure and isotope shift measurements of unclassified lines in Eu II and new determination of the partition function

Furmann¹,

Stefańska²

2013

Results of the measurements of isotope shifts and the hyperfine structure for 31 unclassified spectral lines of Eu II, obtained with the laser-induced fluorescence method, are presented. All experimental results are the first results available for these spectral lines. On the basis of measured hyperfine structure constants, J quantum numbers and fluorescence channels (by comparison to the theoretically predicted values), identification of electronic levels was accomplished. The lower levels of the lines investigated were identified as levels belonging to configuration 4f 7 6s. On the basis of the literature values of isotope shifts for this configuration, isotope shifts for lower and upper levels were determined, and, with the use of a sharing rule, contributions of particular configurations in the spectroscopic description of these levels were evaluated. The number of configurations (cores) necessary for description of the Eu II spectrum and the resulting changes of partition function were estimated. Although, due to the lack of transitions to known electronic levels in Eu II, determination of absolute energies of the levels identified was impossible, probable energy values are presented, which might constitute a starting point for investigations in other spectral regions.

“…In the investigations of the isotope shift and hyperfine structure for spectral lines of europium performed, the experimental setup for laser spectroscopy in a hollow-cathode discharge, previously used in investigations of praseodymium and lanthanum described in [31] and our other works [32][33][34][35][36][37] CR 699-21) operating alternatively on the dyes Rhodamine 6G, DCM and Stilbene 3 was applied. In the cases of the first two dyes, the laser was optically pumped with a frequency-doubled Nd:YVO 4 laser (Coherent, model Verdi V-10), and in the case of the third dye, with all lines UV of the argon ion laser (Spectra Physics, model 2085-15-3.0).…”

Section: Methodsmentioning

confidence: 99%

Isotope shift and hyperfine structure in even configurations of neutral europium

Furmann

Stefańska

2011

Results of the measurements of the isotope shifts, as well as the hyperfine structure constants, are presented concerning electronic levels belonging to the even configurations in a europium atom with energies within the range 28 000-43 000 cm −1 . The data were obtained with the method of laser-induced fluorescence in a hollow-cathode discharge. On the basis of the measurements of 137 spectral lines, the values of isotope shifts and hyperfine structure constants A and B for 69 levels were determined; in the case of 44 levels, these values were obtained for the first time. Relying on the experimental results, the parameters describing the isotope shifts for individual configurations and the crossed second-order effects were calculated. The results obtained were compared to the ab initio estimations.