Investigation of the Hyperfine Structure of Ta I lines (VII)

Abstract

We have classified about 400 new spectral lines of neutral tantalum via laser excitation or observation of laser-induced fluorescence. 37 energy levels with even parity and seven levels with odd parity were found by means of systematic hyperfine structure investigations. For the new levels angular momentum, parity, magnetic hyperfine interaction constant A and electric quadrupole interaction constant B were deduced. In addition, we have classified 230 new lines observed in high resolution Fourier transform spectra by analysing their observed hyperfine structure patterns.

Investigation of the hyperfine structure of Pr I and Pr II lines based on highly resolved Fourier transform spectra

“…Agreement was better than 0.001Å. In the UV and IR region Ar-lines of the present spectrum were compared with Ar-lines of earlier used FT spectra of Ta and Ar, taken at Imperial College London and Kitt Peak National Observatory ( [15]). Again the agreement was better than 0.003Å.…”

A list of tantalum lines for the wavelength calibration of the Hamilton echelle spectrograph

“…This may be due to the fact that the tantalum has an odd number in the periodic table, is subject to the effect of hyperfine splitting of atomic levels. According to the measurements of Messnarz et al (2003), the splitting of spectral lines of tantalum approaches 0.1-0.3 Å. The uneven distribution of the components leads to the asymmetry of the measured line and to the shift of its center.…”

Saturated-configuration-interaction calculations for five-valent Ta and Db

“…Most of the lowest energy odd parity levels as given in [30][31][32] were identified in order and have been presented in table II. All calculated odd levels were within 14% of experimental values, with the majority of levels within 8% of the experimental values, except the E = 15042 cm −1 , J = 5 2 level, which was within 16.5%.…”