Revised and extended analysis of the spectrum of ten-times-ionized cerium (Ce XI)

Atomic properties of Cd-like and Sn-like ions for the development of frequency standards and search for the variation of the fine-structure constant

“…Energies for similar Cd-like Ba 8+ , La 9+ , Ce 10+ , Pr 11+ and Sn-like Ba 6+ ions, where the experimental values are available, were calculated and compared with experiment for further tests of accuracy. Our values are in excellent agreement with experimental energies from [20][21][22] for Cd-like Ba 8+ , La 9+ , Ce 10+ , with similar level of agreement for all three ions. However, we find a significant discrepancy with experimental values from [23,24] for Pr 11+ and Nd +12 which might indicate a problem with the experimental level identification.…”

“…To explore the discrepancy of our energies with experiment for Nd 12+ , we calculated the energies of the other three ions of Cd-like isoelectronic sequence, La 9+ , Ce 10+ , and Pr 11+ , and compared the results with the experimental values from [21][22][23]. We present the comparison of theoretical energies with experiment for all 5 consecutive ions of Cd-like isoelectronic sequence, Ba 8+ [20], La 9+ [21], Ce 10+ [22], Pr 11+ [23], and Nd 12+ [24] in Table II. All energies are given relative to the 5s 2 1 S 0 ground state in cm −1 .…”

“…We note that the 5s 2 1 S 0 − 5s5p 1 P 1 is the only strong easily identifiable line from all of the states considered here. The identification of other numerous ultraviolet (UV) lines is a very difficult task carried out in [21][22][23] using the Cowan code. It may be possible that change in the order of levels for Pr 11+ resulted in TABLE I: Energies of Cd-like Ba 8+ , Nd 12+ , and Sm 14+ ions relative to their ground states evaluated using the CI+all-order method (in cm −1 ).…”

Ground-state configurations and unresolved transition arrays in extreme ultraviolet spectra of lanthanide ions

“…Currently ground configurations of the lanthanides are known experimentally for ion stages up to the third, and fourth in some cases [2]. As noted in [1], systematic analysis of spectra in higher ion stages of lanthanum and cerium have been performed: La VII [9], La XI [10,11], La XIII [12], Ce III [13], Ce V [14], Ce VI [15], Ce IX [16], Ce X [17] and Ce XIV [10][11][12]. More recently progress has been made in analysing Cd-like ion spectra from Xe VII -Eu XVI [5, 18,19] and Pd-like ion spectra [20].…”

Extended analysis of Xe VII and Xe VIII

“…In the studies related with the stimulated emission of xenon, the understanding of the population mechanisms that affect the Xe VII laser action requires knowledge of the spectral analysis corresponding to this ion. Results for ions in the Cdlike isoelectronic sequence were published [7][8][9][10][11][12][13][14][15][16][17] and previous works about cadmiumlike xenon were carried out by different groups of researchers [18][19][20][21][22][23], who used various experimental methods such as beam-foil spectroscopy, spark-light sources, laserproduced plasma, theta-pinches, etc. Larsson et al [24] obtained energy levels of the 5s6s, 5s5d and 5p 2 , and 5s4f configurations by collision-based spectroscopy.…”