Radiative lifetimes, branching fractions and oscillator strengths in PdI and the solar palladium abundance; ; et al in Astronomy and Astrophysics (2006), 452(1), 357-362 Transition probabilities have been derived for 20 5s-5p transitions of Pd I from a combination of radiative lifetime measurements for 6 odd-parity levels with time-resolved laser-induced fluorescence ... [more ▼] Transition probabilities have been derived for 20 5s-5p transitions of Pd I from a combination of radiative lifetime measurements for 6 odd-parity levels with time-resolved laser-induced fluorescence spectroscopy and of branching fraction determination using a hollow cathode discharge lamp. Additional oscillator strengths for 18 transitions have been determined from measured lifetimes and theoretical branching fractions obtained from configuration interaction calculations with core-polarization effects included. These new results have allowed us to refine the palladium abundance in the solar photosphere: A(Pd) = 1.66 +/- 0.04, in the usual logarithmic scale, a result in close agreement with the meteoritic value. [less ▲] Detailed reference viewed: 15 (1 ULg) Transition probabilities and lifetimes in neutral and singly ionized osmium and the Solar osmium abundanceQuinet, Pascal ; ; Biémont, Emile et alin Astronomy and Astrophysics (2006), 448(3), 1207-93 Radiative lifetime measurements have been performed, with a time-resolved laser-induced fluorescence technique, for 12 levels of Os I and for 9 levels of Os II. For 9 levels of Os I and 4 levels of Os II ... [more ▼] Radiative lifetime measurements have been performed, with a time-resolved laser-induced fluorescence technique, for 12 levels of Os I and for 9 levels of Os II. For 9 levels of Os I and 4 levels of Os II, there were no previous experimental data available. From a comparison with new theoretical calculations, taking configuration interactions and core-polarization effects into account, it has been possible to deduce oscillator strengths for 129 transitions of Os I and 137 transitions of Os II of astrophysical interest appearing in the wavelength range 180.0-870.0 nm. These results have allowed us to revise the abundance of osmium in the solar photosphere (log epsilon(Os) = 1.25 +/- 0.11). The newly derived oscillator strengths have been applied as well to derive the osmium abundance in the carbon-rich metal-poor star HD 187861. [less ▲] Detailed reference viewed: 8 (3 ULg) |
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