| 1. |
- Ekman, Jörgen, et al.
(author)
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A spectral study of Te V from MCDHF calculations
- 2013
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In: Journal of Physics B: Atomic, Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 46:9
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Journal article (peer-reviewed)abstract
- State-of-the-art multiconfiguration Dirac-Hartree-Fock calculations for Te V have been performed and energies, LS-compositions, radiative lifetimes and Lande gJ-factors for 51 odd and even parity states are presented. In addition, predictions on transition rates and oscillator strengths for a multitude of transitions between these states are reported for the first time. To describe the atomic system accurately, by means of configuration interaction, valence and core-valence electron correlation effects were taken into account. Calculated energies and lifetimes of excited states agree very well with experimental data.
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| 2. |
- Grumer, Jon, et al.
(author)
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Atomic Data and Stark Broadening Parameters for Sn II and Sn III
- 2013
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In: Book of abstracts. - : Institute of Modern Physics, Chinese Academy of Sciences.
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Conference paper (other academic/artistic)abstract
- Synopsis Extensive multicon guration Dirac-Hartree-Fock (MCDHF) and relativistic con guration interaction (RCI) calculations of energies, transition rates and broadening parameters are reported for Sn II and Sn III, ions which are of importance for plasma modeling. Results are compared with other recent works.
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| 3. |
- Grumer, Jon, et al.
(author)
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Magnetic field induced transition rates in Ne- and Be-like ions for plasma diagnostics and E1M1 two-photon decay rate determination
- 2013
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In: Book of abstracts. - : Institute of Modern Physics, Chinese Academy of Sciences.
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Conference paper (other academic/artistic)abstract
- Synopsis We report on theoretical results of magnetic field induced transitions (MITs) in Ne- and Be-like ions without nuclear spin for two applications. Firstly, MITs are promising candidates in the determination of magnetic fields in plasmas. In our work on Ne-like ions we present accurate theoretical MIT rates for 2p6 1S0 − 2p53s 3P0 , 2 [1]. Furthermore, for Be-like ions, it has been proposed to extract the rate of the E1M1 two-photon transition 2s2 1S0 − 2s2p 3P0 by measuring the lifetime of the 3P0 state using a storage ring, which involves an external magnetic field. The MIT rates are carefully evaluated and shown to be of the same order as the E1M1 rates.
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| 4. |
- Grumer, Jon, et al.
(author)
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The effect of an external magnetic field on the determination of E1M1 two-photon decay rates in Be-like ions
- 2013
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In: Physical Review A. Atomic, Molecular, and Optical Physics. - : American Physical Society. - 1050-2947 .- 1094-1622. ; 88
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Journal article (peer-reviewed)abstract
- In this work we report on ab initio theoretical results for the magnetic-field-induced 2s 2p 3P0 → 2s2 1S0 E1 transition for ions in the beryllium isoelectronic sequence between Z = 5 and 92. It has been proposed that the rate of the E1M1 two-photon transition 2s 2p 3P0 → 2s2 1S0 can be extracted from the lifetime of the 3P0 state in Be-like ions with zero nuclear spin by employing resonant recombination in a storage ring. This experimental approach involves a perturbing external magnetic field. The effect of this field needs to be evaluated in order to properly extract the two-photon rate from the measured decay curves. The magnetic-field-induced transition rates are carefully evaluated, and it is shown that, with a typical storage-ring field strength, it is dominant or of the same order as the E1M1 rate for low- and mid-Z ions. Results for several field strengths and ions are presented, and we also give a simple Z-dependent formula for the rate. We estimate the uncertainties of our model to be within 5% for low- and mid-Z ions and slightly larger for more highly charged ions. Furthermore we evaluate the importance of including both perturber states, 3P1 and 1P1, and it is s
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| 5. |
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| 6. |
- Li, Jiguang, et al.
(author)
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Theoretical investigation of magnetic-field-induced 2p53s 3P0 - 2p6 1S0 transitions in Ne-like ions without nuclear spin
- 2013
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In: Physical Review A. Atomic, Molecular, and Optical Physics. - : American Physical Society. - 1050-2947 .- 1094-1622. ; 88:1
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Journal article (peer-reviewed)abstract
- We report theoretical results for magnetic-field-induced 2p53s 3P0,2 − 2p6 1S0 E1 transitions in Ne-like ions with zero nuclear spin (I = 0) between Mg III and Zn XXI as well as in Ne I.We demonstrate that it is important to include both “perturber” states 2p53s 1P1 and 2p53s 3P1 in order to produce reliable transition rates. Furthermore, we investigate the trends of the rates along the isoelectronic sequence of the 2p53s 3P0,2 − 2p6 1S0 transitions and their competition with the 2p53s 3P0 − 2p53s 3P1 M1 and the 2p53s 3P2 − 2p6 1S0 M2 decays. For the 2p53s 3P0 state the magnetic-field-induced transition becomes the dominant decay channel for the light elements even in a relatively weak magnetic field, and it will therefore prove useful in diagnostics of the strength of magnetic fields in different plasmas. The influence of an external magnetic field on the lifetime of the 2p53s 3P2 state is much smaller but still observable for the ions near the neutral end of the sequence. As a special case, the magnetic field effect on the lifetimes of 2p53s 3P0,2 states of neutral 20Ne is discussed. It is found that the lifetimes are drastically reduced by a magnetic field, which may be an underlying reason for the discrepancies in the lifetime of the 2p53s 3P2 state between experiment [14.73(14) s] and theory (17.63 s).
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| 7. |
- Petryla, Andrius, et al.
(author)
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Theoretical and experimental studies of In I, Sn II, Sb III, and Te IV atomic properties
- 2012
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In: Europhysics Conference Abstracts;36C. - : European Physical Society. ; , s. 42-42
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Conference paper (other academic/artistic)abstract
- We use relativistic multiconfiguration Dirac-Hartree-Fock and configuration interaction calculations to study 5s2nl and 5s5p2 configurations of In I, Sn II, Sb III, and Te IV. Energies, transition amplitudes, Land´e gJ-factors, and hyperfine constants are calculated using a correlation model that accounts for valence and core-valence correlation. Also spin- and orbital polarization effects are accounted for by single excitations from all core-shells to an increasing set of active orbitals. Transformed to the LSJ-coupling scheme, using the new features of the GRASP2K program, the calculated wave functions shed light on the difficulties in labeling some states due to the extensive 5s25d and 5s5p2 configuration interaction. Our results are compared with experimental values and values from relativistic many-body perturbation theory (RMBPT) and all-order single-double (SD) calculations. The theoretical work is complemented with experiment, and new hyperfine interaction constants are derived for several states in In I from high resolution Fourier Transform Spectra.
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| 8. |
- Verdebout, Simon, et al.
(author)
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Spectral properties of In II, Sn III, Sb IV, and Te V in the Cd-sequence from large scale MCDHF and RCI calculations
- 2012
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In: Europhysics Conference Abstracts;36C. - : European Physical Society. ; , s. 136-136
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Conference paper (other academic/artistic)abstract
- We report on extensive relativistic multiconfiguration Dirac-Hartree-Fock and relativistic configuration interaction spectrum calculations for In II, Sn III, Sb IV, and Te V in the Cdsequence. For each ion, energies, LS-composition, and Land´e gJ-factors for up to 60 odd and even parity states are computed along with lifetimes and E1 and M1 rates for transitions between these states. Results for the 5s2 1S0 → 5s5p 3Po0 hyperfine induced transition are also presented. Valence and core-valence electron correlation effects are accounted for by explicit configuration interaction. The calculated energies are based on expansions with several hundred thousand configuration state functions (CSFs), and agree well with recent experiment, but the labeling of some of the odd states are ambiguous due to close degeneracies between several configurations. Calculated lifetimes of the excited states are in good agreement with values from cascade corrected beam-foil measurements.
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