Relativistic many-body calculations of the oscillator strengths, transition rates and polarizabilities in Zn-like ions

Abstract

Transition rates, oscillator strengths and line strengths are calculated for electric-dipole (E1) transitions between even-parity 4s 2 , 4p 2 , 4s4d, 4d 2 , 4p4f and 4f 2 states and odd-parity 4s4p, 4s4f, 4p4d and 4d4f states in Zn-like ions with the nuclear charges ranging from Z = 32 to 100. Relativistic many-body perturbation theory (RMBPT), including the Breit interaction, is used to evaluate retarded E1 matrix elements in length and velocity forms. The calculations start from a 1s 2 2s 2 2p 6 3s 2 3p 6 3d 10 Dirac-Fock potential. First-order RMBPT is used to obtain intermediate coupling coefficients and second-order RMBPT is used to calculate transition matrix elements. Contributions from negative-energy states are included in the second-order E1 matrix elements to ensure the gauge independence of transition amplitudes. Transition energies used in the calculation of oscillator strengths and transition rates are from second-order RMBPT. Ground state scalar α 0 (4s 2 1 S 0) polarizabilities are calculated for Zn-like ions from Z = 33 to 100. To evaluate the α 0 (4s 2 1 S 0) polarizabilities, we calculate RMBPT energies for the odd-parity 4l5l complex with J = 1 and line strengths between the even-parity 4l4l complex with J = 0 and the odd-parity 4l5l , 4l6l complexes with J = 1.

Recent progress in spectroscopy of tungsten1This review is part of a Special Issue on the 10th International Colloquium on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas.

“…Their calculated energies are in good agreement with the RMBPT calculations of Safronova and Safronova [27,28] and with other high-precision calculations discussed above. The calculated rates provide another set of data for comparison with other calculations and will help to evaluate the accuracy of calculations.…”

“…However, the complete omission of the work of Brown et al [101] in the compilation [1] was a mistake. Now, the good agreement between the RMBPT calculations of Safronova and Safronova [27,28], MRMP calculations of Vilkas and Ishikawa [102], semiempirical results of Brown et al [101], and several firmly established experimental values of energy levels [1] makes it possible to confirm the accuracy of the measurements of Brown et al [101], and confirm several of their line identifications. Some of their identifications must be rejected because they contradict more precise measurements adopted in [1].…”

“…Another work of Safronova and Safronova [28] gives results of RMBPT calculations of energy levels and radiative rates in Zn-like ions from Z = 32 to 100. They compare their calculated wavelengths with experimental data for the 4s 2 -4s4p, 4s4p-4s4d, and 4s4p-4p 2 transitions in the interval Z = 70-92.…”

Multiconfiguration calculations of electronic isotope-shift factors in Zn i

“…There are many theoretical studies of properties such as oscillator strengths, lifetimes, polarizabilities, and hyperfine structure constants in Zn I and Zn-like ions [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27]. By contrast, to the best of our knowledge, no recent paper reporting on theoretical IS electronic factors in Zn I has been published since the pioneering works led by Bauche and Crubellier [28,29] reporting only on SMS factors, and by Blundell et al [30,31] only on FS factors.…”

Measurement of dynamic Stark polarizabilities by analyzing spectral line shapes of forbidden transitions

“…The present experiments typically rely on theoretical calculations of electric dipole polarizabilities [15][16][17]. Several methods for measuring polarizabilities also exist.…”