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- Carlsson, J, et al.
(author)
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Lifetimes and Transition-probabilities of the Boron Atom Calculated With the Active-space Multiconfiguration Hartree-fock Method
- 1994
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In: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 49:5, s. 3426-3431
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Journal article (peer-reviewed)abstract
- Systematic multiconfiguration Hartree-Fock results are presented for the transition probabilities and excited-state lifetimes in the term system of the boron atom. Particularly, the interaction between the 1s(2)2s2p2 configuration and the 1s(2)2s2ns2S and 1s(2)2s2nd2D Rydberg series is considered. Term energies and transition-matrix elements are calculated to convergence using increasing active sets of s, p, d, f, and g orbitals.
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- Fischer, Charlotte, et al.
(author)
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Mchf Calculations For Atomic Properties
- 1994
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In: Computer Physics Communications. - 0010-4655. ; 84:1-3, s. 37-58
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Journal article (peer-reviewed)abstract
- A historical review of the early development of Hartree-Fock and Multiconfiguration Hartree-Fock theories is presented. After the underlying theory is summarized, some recent results from the application of these methods to the prediction of atomic properties are described. These include total energies, transition probabilities, autoionization rates, specific mass shifts, and hyperfine parameters. In each case, large-scale, systematic procedures are used to show the convergence of the theoretically predicted results.
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- Jönsson, Per, et al.
(author)
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Accurate Calculation of the Isotope Shift and Hyperfine-structure In the Boron (b-ii) Line At 1362 Angstrom
- 1994
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In: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 429:1
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Journal article (peer-reviewed)abstract
- An extensive multiconfiguration Hartree-Fock (MCHF) calculation of the isotope shift and hyperfine structure in the resonance line of B II at 1362 angstrom has been performed. The calculated B-11-B-10 isotope shift is 13.3 mangstrom with an estimated uncertainty of 1%. The calculated interaction constants A and B give a hyperfine structure splitting of less than 0.45 mangstrom for both isotopes. The size of the isotope shift in the B II line is similar to the limit of detection in high-resolution observations with the Goddard High Resolution Spectrograph aboard the Hubble Space Telescope when side A becomes operational after the service mission.
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7. |
- Jönsson, Per, et al.
(author)
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Large-scale Multiconfiguration Hartree-fock and Configuration-interaction Calculations of Isotope Shifts and Hyperfine Structures In Boron
- 1994
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In: Physical Review A (Atomic, Molecular and Optical Physics). - 1050-2947. ; 50:4, s. 3080-3088
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Journal article (peer-reviewed)abstract
- A new isotope shift program, part of the multiconfiguration Hartree-Fock (MCHF) atomic structure package, has been written and tested. The program calculates the isotope shift of an atomic level from MCHF or configuration-interaction (CI) wave functions. The program is specially designed to be used with very large CI expansions, for which angular data cannot be stored on disk. To explore the capacity of the program, large-scale isotope shift calculations were performed for the 1s(2)2s(2)2p 2P, 1s(2)2s(2)3s2S, and 1s(2)2s2p2 2D levels in boron. From the isotope shifts of these levels the transition isotope shifts were calculated for the two resonance transitions. The calculated transition isotope shifts are in very good agreement with experimental shifts. As an additional test of the quality of the CI wave functions, the hyperfine structure was calculated for all levels.
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