scholarly journals Radiative transitions for three lowest configurations of tungsten ions W38+–W43+

2017 ◽  
Vol 57 (3) ◽  
Author(s):  
Rasa Karpuškienė ◽  
Pavel Bogdanovich ◽  
Romualdas Kisielius
Keyword(s):  
Transition Probabilities ◽  
Relativistic Effects ◽  
Electric Quadrupole ◽  
Radiative Transition ◽  
Configuration Interaction Method ◽  
Hartree Fock ◽  
Radiative Transitions ◽  
Emission Transition ◽  
Magnetic Quadrupole ◽  
Electron Correlation Effects

The ab initio quasirelativistic approximation was used to derive transition data for the multicharged tungsten ions W38+–W43+ with an open 4p shell. The configuration interaction method with transformed radial orbitals was applied to include electron correlation effects. The relativistic effects were taken into account in the Breit–Pauli approximation for the quasirelativistic Hartree–Fock radial orbitals. The level energies E, radiative lifetimes τ, and Landé g-factors were calculated for the 4s24pN, 4s24pN–14d, and 4s4pN+1 configurations of six tungsten ions. The radiative transition wavelengths λ, spontaneous emission transition probabilities A and their uncertainties for the electric dipole, electric quadrupole, electric octupole, magnetic dipole and magnetic quadrupole transitions among the levels of these configurations are presented.

An Investigation on the Fine Structure Levels in the Ground State Configuration for the Antimony Anion

2014 ◽  
Vol 69 (8-9) ◽  
pp. 397-402
Author(s):  
Leyla Özdemir ◽  
Sadiye Tuna
Keyword(s):  
Fine Structure ◽  
Ground State ◽  
Transition Probabilities ◽  
Relativistic Effects ◽  
Electric Quadrupole ◽  
Radiative Transition ◽  
Ground State Configuration ◽  
Hartree Fock ◽  
First Time ◽  
State Configuration

We have investigated the correlation, relativistic, and isotope shift effects on the fine structure levels in the ground state configuration for the antimony anion ( Sb-). Energies and radiative transition probabilities (for magnetic dipole, M1, and electric quadrupole, E2) have been obtained using the multiconfiguration Hartree-Fock method within the framework of the Breit-Pauli Hamiltonian. Therefore, the most important configuration interaction and relativistic effects have been included. Comparisons with other available works are presented. For some M1 and E2 lines the considered transition probabilities are reported for the first time

scholarly journals X-Ray Satellite Lines

1984 ◽  
Vol 86 ◽  
pp. 36-36
Author(s):  
J. Dubau
Keyword(s):  
Transition Probabilities ◽  
Relativistic Effects ◽  
Radiative Transition ◽  
Electron System ◽  
Great Accuracy ◽  
Atomic Data ◽  
X Ray ◽  
Spectroscopic Diagnostics ◽  
Radiative Transitions ◽  
Shell Vacancy

Satellite lines are typical features of X-ray spectra. They correspond to radiative transitions involving an inner-shell vacancy. The most studied satellite lines are of the - type, i.e., (ls–2p) transition.With the advent of Space Astronomy, X-ray spectra emitted by very hot solar plasma have been obtained. By a simple comparison of different spectra, it appears that, for highly ionized atoms, some satellite lines have intensities as large as resonance lines intensities and, more particularly, this is the case for the ls2n. – ls 2pn satellite lines of the 1s2 – ls2p resonance lines.The analysis of the different population mechanisms responsible for the satellite lines and resonance lines emission has shown that different spectroscopic diagnostics could be derived from line ratios only if atomic data of great accuracy were available. There exists nowadays different atomic data programs adapted to X-ray satellite lines. They have in common to give a great amount of data simultaneously: wavelengths, autoionization and radiative transition probabilities. They take into account correlation and relativistic effects.After tackling the simple 3-electron system, the programs give now appropriate data for more complex systems but this required large computers because the lines become blended. It is therefore impossible to limit the calculation to the most intense lines.

Kα transition probabilities of C-like to F-like Al ions

2015 ◽  
Vol 93 (3) ◽  
pp. 267-270
Author(s):  
Cuicui Sang ◽  
Feng Chen ◽  
Chao Chen ◽  
Bingcong Gou
Keyword(s):  
Transition Probabilities ◽  
Energy Levels ◽  
Emission Spectra ◽  
Radiative Transition ◽  
Transition Rates ◽  
Atomic Structures ◽  
Radiative Transitions ◽  
Electron Correlation Effects ◽  
Reasonable Description ◽  
Spectral Intensities

Kα radiative transitions of C-like to F-like Al ions are studied using the multiconfiguration Dirac–Fock (MCDF) method. The fully relativistic MCDF approach was specifically designed to calculate atomic structures and radiative transition rates, and hence it ensures a reasonable description of the emission effects and spectral intensities. The energies and wavefunctions, corresponding mixing coefficients, the influence of electron correlation effects on energy levels, and radiative transition rates for C-like to F-like Al ions are investigated in detail. Good agreement is found between the calculated Kα emission spectra in this work and the spectra from experimental measurements.

Energy spectra of the tungsten ion 4s24pN, 4s24N–14d and 4s4pN+1 configurations

2015 ◽  
Vol 55 (3) ◽  
Author(s):  
Pavel Bogdanovich ◽  
Rasa Karpuškienė ◽  
Romualdas Kisielius
Keyword(s):  
Energy Level ◽  
Configuration Interaction ◽  
Electron Correlation ◽  
Relativistic Effects ◽  
Energy Spectra ◽  
Correlation Effects ◽  
Interaction Method ◽  
Configuration Interaction Method ◽  
Hartree Fock ◽  
Electron Correlation Effects

The ab initio quasirelativistic Hartree–Fock approximation was used to determine spectroscopic parameters for the multicharged tungsten ions with an open 4p shell. The configuration interaction method based on the transformed radial orbitals was applied to include the electron-correlation effects. The relativistic effects were taken into account in the Breit–Pauli approximation for the quasirelativistic Hartree–Fock radial orbitals. The complete energy level spectra were calculated for the 4s24pN, 4s24pN–14d and 4s4pN+1 configurations of the tungsten ions from W43+ to W38+.

Energies and radiative transitions (E1, E2, and M1) for hydrogen-like thorium

2016 ◽  
Vol 94 (11) ◽  
pp. 1138-1141 ◽  
Author(s):  
G. Ürer
Keyword(s):  
Atomic Structure ◽  
Quantum Electrodynamics ◽  
Transition Probabilities ◽  
Spectral Characteristics ◽  
Relativistic Effects ◽  
Theoretical Work ◽  
Oscillator Strengths ◽  
Hartree Fock ◽  
Radiative Transitions ◽  
Calculated Level

Hydrogen-like ions with high Z present unique opportunities to promote the understanding of atomic structure. On the other hand, determining the atomic structure of hydrogen-like atoms provides us the test of relativistic effects as well as accurate values of the spectral characteristics required for many applications. For this reason we have calculated level energies of hydrogen like thorium (Th89+, Z = 90) with both multiconfiguration Hartree–Fock (MCHF) and multiconfiguration Dirac–Fock (MCDF) methods. These calculations have contained the Breit–Pauli relativistic corrections in MCHF calculation and quantum electrodynamics effects in MCDF calculations besides electron correlations. The wavelengths, λ, weighted oscillator strengths, gf-value, and transition probabilities, Aki, have been also represented for allowed (E1) and forbidden (E2 and M1) transitions. We have compared our results with only theoretical work results because there is no available experimental data for Th89+.

scholarly journals Recombination Spectra of Planetary Nebulae

1983 ◽  
Vol 103 ◽  
pp. 514-516
Author(s):  
P.O. Bogdanovich ◽  
Z.B. Rudzikas ◽  
T. H. Feklistova ◽  
A.F. Kholtygin ◽  
A.A. Nikitin ◽  
...  
Keyword(s):  
Transition Probabilities ◽  
Planetary Nebulae ◽  
Dielectronic Recombination ◽  
Wave Functions ◽  
Energy Spectra ◽  
Coupling Scheme ◽  
Intermediate Coupling ◽  
Hartree Fock ◽  
Radiative Transitions ◽  
Intermediate Coupling Scheme

The lines of the transitions between the subordinate levels of the CIII, NIII etc. ions are observed in the spectra of planetary nebulae (PN) (1). Their theoretical intensities may be found by solving the stationarity equations and accounting for both the recombination and cascade radiative transitions. It is possible to calculate the recombination spectra in various approaches: the single- or multi-configuration approximations (SCA and MCA) making use of both the superposition of configurations (SC) or the multiconfigurational Hartree-Fock-Jucys equations (2), taking into consideration the contribution of the dielectronic recombination to the intensities of the recombination lines. The energy spectra, the transition probabilities etc., as a rule ought to be calculated in the intermediate coupling scheme (2). Both analytical or numerical (e.g. Hartree-Fock) wave functions may be adopted.

scholarly journals Population of Excited States of Al10+ in a Plasma by a Time-Dependent Model

1984 ◽  
Vol 86 ◽  
pp. 221-224
Author(s):  
H. Guennou ◽  
A. Sureau
Keyword(s):  
Population Distribution ◽  
Transition Probabilities ◽  
Ground Level ◽  
Radiative Transition ◽  
Time Dependent ◽  
Hartree Fock ◽  
Ion Collisions ◽  
Finite Set ◽  
Dependent Model ◽  
Time Dependent Model

The present model is the time-dependent version of a previous model (Sureau et al. 1983) in which the population distribution was assumed in steady state. A finite set of levels is partitioned in four subsets: the Z-ion ground-level and, contingently, the first near-degenerated levels (subset 1); all the successive excited Z-ion levels up to n=5 (subset 2); a finite number of higher Rydberg levels (because of the limitation of the series in the plasmas) which are assumed in LTE with the Z+l−ion ground-level (subset 3, called the thermal band); and the Z+l ion ground-level (subset 4).The physical processes explicitly considered are the radiative cascades and the transitions between the Z-ion bound levels induced by electron-ion collisions. The radiative-transition probabilities are given by ab-initio calculations using a modified Hartree-Fock method including the spin-orbit interaction (Sureau et al., 1984). The collision rates are derived by the Van Regemorter formula multiplied by an adjustable parameter Fc.

scholarly journals Transition Parameters for Doubly Ionized Lanthanum

2012 ◽  
Vol 2012 ◽  
pp. 1-15 ◽  
Author(s):  
Betül Karaçoban ◽  
Leyla Özdemir
Keyword(s):  
Least Squares ◽  
Configuration Interaction ◽  
Electric Dipole ◽  
Transition Probabilities ◽  
Energy Levels ◽  
Relativistic Effects ◽  
Oscillator Strengths ◽  
Least Squares Fitting ◽  
Hartree Fock

The transition parameters such as the wavelengths, weighted oscillator strengths, and transition probabilities (or rates) for the nd (n=5−9)−nf (n=4−8), nd (n=5−9)−np (n=6−9), np (n=6−9)−ns (n=6−10), and ng (n=5−8)−nf (n=4−8) electric dipole (E1) transitions of doubly ionized lanthanum (La III, Z=57) have been calculated using the relativistic Hartree-Fock (HFR) method. In this method, configuration interaction and relativistic effects have been included in the computations combined with a least squares fitting of the Hamiltonian eigenvalues to the observed energy levels. We have compared the results obtained from this work with the previously available calculations and experiments in literature. We have also reported new transitions with the weighted transition probabilities greater than or equal to 105.

Accurate study on the properties of spectral lines for Na-like Cr13+

2019 ◽  
Vol 97 (4) ◽  
pp. 436-442
Author(s):  
A.K. Singh ◽  
Mayank Dimri ◽  
Dishu Dawra ◽  
Alok K.S. Jha ◽  
Man Mohan
Keyword(s):  
Configuration Interaction ◽  
Energy Levels ◽  
Electric Quadrupole ◽  
General Purpose ◽  
Spectral Lines ◽  
Oscillator Strengths ◽  
Fusion Plasma ◽  
Configuration Interaction Method ◽  
Magnetic Quadrupole ◽  
Configuration Interaction Calculations

An extended calculation of energy levels, radiative rates, and lifetimes are reported for sodium-like chromium. Extensive configuration interaction calculations have been performed using general-purpose relativistic atomic structure package (GRASP). The radiative rates, oscillator strengths, and line strengths are listed for all electric dipole (E1) transitions. However, for magnetic dipole (M1), electric quadrupole (E2), and magnetic quadrupole (M2) transitions, only radiative rates are listed. The importance of valence–valence (VV) and core–valence (CV) correlation effects in the calculation of energy levels have also been shown. To confirm the accuracy of the present results for energy levels by GRASP, independent calculations have been performed by using Flexible Atomic Code (FAC) and configuration interaction method (CIV3). The accuracy of the present levels, wavelengths, transition rates, and lifetimes are assessed by comparing them to available experimental and other theoretical results. We believe that our extensive results may be beneficial in fusion plasma research and astrophysical investigations and applications.

scholarly journals Allowed and Forbidden n = 2?2 Transitions of the Elements Kr and Mo

1984 ◽  
Vol 37 (6) ◽  
pp. 601
Author(s):  
R Glass
Keyword(s):  
Transition Probabilities ◽  
Relativistic Effects ◽  
Correlation Effect ◽  
Coupling Scheme ◽  
Intermediate Coupling ◽  
Transition Energies ◽  
Hartree Fock ◽  
Physical Assumption ◽  
Variational Process ◽  
Intermediate Coupling Scheme

Relativistic intermediate-coupling wavefunctions are used to evaluate transition energies, line strengths and transition probabilities for all allowed and forbidden n = 2-2 transitions for krypton and molybdenum beryllium-like ions. Our results are in very good agreement with those calculated using the relativistic multi-configuration Hartree-Fock approximation. These calculations were carried out under the same physical assumption that the dominant correlation effect is the n = 2 intra-shell correlation. We also discuss the importance of relativistic effects on the radial functions, the relativistic intermediate-coupling scheme in the variational process, the importance of radiative corrections for transition energies between states with different occupation of the 2s shell, and the relative importance of intra- versus inter-shell correlation effects.

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