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Prominent Soft X-ray Lines of Sr-like Au41+ in Low-energy EBIT Spectrum

Description: Relativistic multireference M{o}ller-Plesset perturbation theory has been employed to calculate with high accuracy the energy levels and transition probabilities of Cu- to Sr-like gold ions. The many-body calculations were carried out to identify the unassigned blended lines in the 35-40 angstroms region of the low-energy EBIT spectrum of the gold ions. Most of the prominent lines in the 35-40 angstroms region were identified as the emission lines in Sr-like gold.
Date: March 27, 2007
Creator: Vilkas, M J; Ishikawa, Y & Trabert, E
Partner: UNT Libraries Government Documents Department

Relativistic multireference many-body perturbation theory calculations on Au64+ - Au69+ ions

Description: Many-body perturbation theory (MBPT) calculations are an adequate tool for the description of the structure of highly charged multi-electron ions and for the analysis of their spectra. They demonstrate this by way of a re-investigation of n=3, {Delta}n=0 transitions in the EUV spectra of Na-, Mg-, Al-like, and Si-like ions of Au that have been obtained previously by heavy-ion accelerator based beam-foil spectroscopy. They discuss the evidence and propose several revisions on the basis of the multi-reference many-body perturbation theory calculations of Ne- through P-like ions of Au.
Date: March 31, 2006
Creator: Vilkas, M J; Ishikawa, Y & Trabert, E
Partner: UNT Libraries Government Documents Department

Relativistic multireference many-body perturbation theory calculations on F-, Ne-, Na-, Mg-, Al-, Si-, and P-like xenon ions

Description: Many-Body Perturbation Theory (MBPT) has been employed to calculate with high wavelength accuracy the extreme ultraviolet (EUV) spectra of F-like to P-like Xe ions. They discuss the reliability of the new calculations using the example of EUV beam-foil spectra of Xe, in which n = 3, {Delta}n = 0 transitions of Na-, Mg-, Al-like, and Si-like ions have been found to dominate. A further comparison is made with spectra from an electron beam ion trap, that is, from a device with a very different (low density) excitation balance.
Date: December 22, 2005
Creator: Vilkas, M J; Ishikawa, Y & Trabert, E
Partner: UNT Libraries Government Documents Department

Relativistic Many-body Moller-Plesset Perturbation Theory Calculations of the Energy Levels and Transition Probabilities in Na- to P-like Xe Ions

Description: Relativistic multireference many-body perturbation theory calculations have been performed on Xe{sup 43+}-Xe{sup 39+} ions, resulting in energy levels, electric dipole transition probabilities, and level lifetimes. The second-order many-body perturbation theory calculation of energy levels included mass shifts, frequency-dependent Breit correction and Lamb shifts. The calculated transition energies and E1 transition rates are used to present synthetic spectra in the extreme ultraviolet range for some of the Xe ions.
Date: March 27, 2007
Creator: Vilkas, M J; Ishikawa, Y & Trabert, E
Partner: UNT Libraries Government Documents Department

Electric-dipole 5s - 5p Transitions in Promethiumlike Ions

Description: The 5s-5p electric-dipole resonance transitions in highly ionized promethiumlike ions have been studied applying relativistic multi-reference Moeller-Plesset second-order perturbation theory. The transition wavelengths are determined to within 0.2 {angstrom} in the more highly charged ions, where the level degeneracies are small. For somewhat lighter ions a very large reference space was used in order to account for the many degeneracies. In order to calculate transition probabilities and lifetimes, correlation corrections have been added to the transition operator in the next order. The contributions from the higher orders of the theory, that is, frequency-dependent Breit correction, Lamb shift, and mass shifts, have been estimated. The results are used to re-assess spectroscopic data from beam-foil, electron beam ion trap, and tokamak observations.
Date: February 29, 2008
Creator: Vilkas, M J; Ishikawa, Y & Trabert, E
Partner: UNT Libraries Government Documents Department