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Full-Text Articles in Physical Sciences and Mathematics
Radiative Lifetimes, Branching Ratios, And Absolute Transition Probabilities In Cr Ii And Zn Ii, Scott D. Bergeson, J. E. Lawler
Radiative Lifetimes, Branching Ratios, And Absolute Transition Probabilities In Cr Ii And Zn Ii, Scott D. Bergeson, J. E. Lawler
Faculty Publications
New absolute atomic transition probability measurements are reported for 12 transitions in Cr II and two transitions in Zn II. These transition probabilities are determined by combining branching ratios measured by classical techniques and radiative lifetimes measured by time-resolved laser-induced fluorescence. The measurements are compared with branching fractions, radiative lifetimes, and transition probabilities in the literature. The 206 nm resonance multiplets in Cr II and Zn II are included in this work. These multiplets are very useful in determining the distribution of the elements in the gas versus grain phases in the interstellar medium.
Oscillator Strengths Of The Si Ii 181 Nanometer Resonance Multiplet, Scott D. Bergeson, J. E. Lawler
Oscillator Strengths Of The Si Ii 181 Nanometer Resonance Multiplet, Scott D. Bergeson, J. E. Lawler
Faculty Publications
We report Si II experimental log (gf)-values of –2.38(4) for the 180.801 nm line, of –2.18(4) for the 181.693 nm line, and of –3.29(5) for the 181.745 nm line, where the number in parenthesis is the uncertainty in the last digit. The overall uncertainties (~10%) include the 1 σ random uncertainty (~6%) and an estimate of the systematic uncertainty. The oscillator strengths are determined by combining branching fractions and radiative lifetimes. The branching fractions are measured using standard spectroradiometry on an optically thin source; the radiative lifetimes are measured using time-resolved laser-induced fluorescence.