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Quantum mechanical study of transition probabilities, Einstein A coefficients, and oscillator strengths of band systems of diatomic molecules
Oscillator strengths and wavelengths of X ray and EUV transitions in highly ionized iron line spectra
Hydrogen and deuterium oscillator strengths and transition probabilities for Lyman and Werner system individual bands by electronic dipole moment functions
Measurements of the oscillator strengths of the ultraviolet lines of neutral nickel obtained by the use of the combined hook and absorption technique are reported. A total of 221 transitions in the range 1964-4094 A was measured for nickel atoms from a high-temperature graphite furnace (2000-2500 K) using a continuum background source, a Mach-Zehnder interferometer and a 3-m Czerny-Turner spectrograph. Hook and absorption measurements are presented, and radiative lifetimes are derived from log gf values. Comparison of the present values with previous results indicates only those of Bell et al. (1966) and Lennard et al. (1975) to consistently agree with the data presented, although the reliability laser-excitation technique of lifetime measurement is supported over that of Hanle methods.
Born approximation used in calculating wave functions of helium atom for determining generalized oscillator strengths in first ionized continuum of helium
Electronic oscillator strengths for nitrogen second positive and nitrogen first negative systems from observations of shock layers about hypersonic projectiles
Shock tube measurement of autoionization lifetime and oscillator strengths of states above first ionization potential for aluminum
Flash photolysis produced methyl and methylene radical transitions maximum extinction coefficients and oscillator strength in vacuum UV
The stopping of a charged particle by isolated atoms is investigated theoretically using an 'atomic plasma' model in which atomic oscillator strengths are replaced by the plasma frequency spectrum. The plasma-frequency correction factor for individual electron motion proposed by Pines (1953) is incorporated, and atomic mean excitation energies are calculated for atoms through Sr. The results are compared in a graph with those obtained theoretically by Inokuti et al. (1978, 1981) and Dehmer et al. (1975) and with the experimental values compiled by Seltzer and Berger (1982): good agreement is shown.
Oscillator strengths and autoionization lifetime of aluminum I doublet measured in shock tube
Atomic O 1302 A and 1152 A lines oscillator strengths determined from radiative lifetimes measured by phase shift
He isoelectronic sequence 3d-nf transitions, determining UV wavelengths and oscillator strengths
Theoretical calculations of selected excitation energies and oscillator strengths for Ba are presented that overcome the difficulties of previous theoretical treatments. A relativistic effective-core potential treatment is used to account for the relativistic core contraction, but the outermost ten electrons are treated explicitly. Core-valence correlation can be included in this procedure in a rigorous and systematic way through a configuration-interaction calculation. Insight is gained into the importance of relativistic effects by repeating many of the calculations using an all-electron nonrelativistic treatment employing an extended Slater basis set. It is found that the intensity of the intercombination line 3P1-1S0 is accurately determined by accounting for the deviation from LS coupling through spin-orbit mixing with the 1P1 state, and that deviations from the Lande interval rule provide an accurate measure of the degree of mixing.
Absolute absorption values of four strongest bands in molecular N dipole, determining oscillator strengths
Oscillator strengths for 134 lines from the ground term of neutral titanium have been measured by the hook method. The data, which are normalized to those of Bell, Kalman and Tubbs, agree well with most previously measured data but indicate that there is a line strength dependent error in the National Bureau of Standards compilation of TiIf-values by Wiese and Fuhr.
Band oscillator strengths (f-values) for four bands of the Fourth Positive system (A (1)Pi - Chi(sup 1) Sigma(+)) of CO have been determined from high-resolution (lambda/Delta lambda approximately equal to 150,000) absorption spectra. The bands, (14, 0) through (11, 0), are at wavelengths between 121 and 127 nm. Our f-values for the (11, 0) and (12, 0) bands support those of Chan, Cooper, & Brion (1993), which have been shown to be consistent with observations of CO in the clouds in the line of sight to zeta Oph. Our f-values for the (13, 0) and (14, 0) bands are the first directly measured values for these bands.
Ca, Mg, B and Al prominent resonance transitions radiative lifetimes and absolute oscillator strengths
The hook method, which makes use of anomalous dispersion, was employed to measure 107 absolute oscillator strengths of Fe I on a high-temperature furnace. The absolute scale was established before and after each run by recording the anomalous dispersion near a strong resonance line with accurately known f-value. The results cover three lines with wavelengths from 1934 to 1941 A, and 104 lines lying between 2084 and 3194 A - mostly transitions originating from the a 5 D ground state. The average error of the f-values is plus or minus 20%, and the largest and smallest errors given are plus or minus 10 and plus or minus 60%. Disagreements exceeding an order of magnitude are found with previous values in the literature.