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Extensive relativistic configuration interaction calculations have been performed for the 4d104f and 4d105s states of the Ag-like isoelectronic ion using the GRASP2K package based on the multi-configuration Dirac-Fock method. The active space techniques have been employed to extend the configuration expansion systematically. The electron correlation effects, Breit interaction and quantum electrodynamics effects to the atomic state wavefunctions and the corresponding energies have been taken into account. Good agreement has been obtained in a general trend with the existing experimental and theoretical values. The change of the ground state configuration from 4d105s to 4d104f is predicted to occur at Z = 62. The transition energy and probability of the M1 transition between the 4d104f multiplets are, respectively, scaled to be 0.01(Z* )4 cm-1 and 1.95 × 10-17(Z* )11.97 s-1, where Z* = Z - 34.42 is the effective nuclear charge number for Ag-like ions with Z > 62. Our results show the need for more high-precision experiments for Z >68 ions. [ABSTRACT FROM AUTHOR]

In this work, the KLL dielectronic recombination (DR) processes of highly charged He-like to O-like xenon ions are studied systematically by using a DR program, which is based on the multi-configuration Dirac-Fock (MCDF) method. The KLL DR resonant energies and the corresponding resonant strengths are calculated, emphasizing especially the effect of the Breit interaction on the DR strengths. The theoretical KLL DR spectra are obtained and compared with the latest experimental results obtained in the Shanghai Electron Beam Ion Trap. [ABSTRACT FROM AUTHOR]

We systematically study the decay properties of the K-shell excited F-like ions with 10≤ Z ≤36 based on the multiconfiguration Dirac-Fock method. The Breit interaction, the QED corrections and the nuclear finite mass effects are also considered as perturbation. Auger transition rates, radiative, Auger and natural widths, as well as fluorescence and Auger yields for K-shell excited F-like ions are presented. It is shown by means of concrete figures that the decay properties change significantly with the increase of the atomic number Z; the Auger rate is overtaken at Z = 30 by the radiative decay rate. Several fitting formulae for the radiative and Auger widths and the fluorescence yields have been evaluated which is expected to be useful in plasma analysis and plasma modeling. [ABSTRACT FROM AUTHOR]

An atomic kinetics code is developed to gain insight into the generation of polarized Healpha by fast electron transport relevant to fast ignition. The calculation predicts a very small polarization in the dense region (>or=100 times the critical density) due to frequent elastic transitions between magnetic sublevels, while high polarization is observable in the low density region (

We have observed K-shell and L-shell hollow beryllium atoms (2s(2)2p3s and 1s3s(2)3p) created by photoexcitation using synchrotron radiation. Resonance shapes were fitted to the Fano profile and the parameters were deduced. A Dirac-Fock calculation was performed to identify the configuration of the peaks and to predict other hollow atomic peaks. The results of the calculation were in good agreement with the experimental data. The comparison of the transition strength has revealed that the three-electron photoexcitation to the 1s3s(2)3p configuration is stronger than the two-electron photoexcitation to the 2s(2)2p3s configuration. This is attributed to the large overlap between the 2s orbital of the ground state (1s(2)2s(2)) with the orbital of the L-shell hollow state (1s3s(2)3p).

A population kinetics code was developed to analyze K alpha emission from partially ionized chlorine atoms in hydrocarbon plasmas. Atomic processes are solved under collisional-radiative equilibrium for two-temperature plasmas. It is shown that the fast electrons dominantly contribute to ionize the K-shell bound electrons (i.e., inner-shell ionization) and the cold electrons to the outer-shell bound ones. Ratios of K alpha lines of partially ionized atoms are presented as a function of cold-electron temperature. The model was validated by observation of the K alpha lines from a chlorinated plastic target irradiated with 1 TW Ti:sapphire laser pulses at 1.5 x 10(17) W/cm(2), inferring a plasma temperature of about 100 eV on the target surface.