相关论文: Oscillator Strengths for Ultraviolet Transitions i…
We report lifetimes, branching fractions, and the resulting oscillator strengths for transitions within the P II multiplet (3s^23p^2 ^3P - 3s^23p4s ^3P^o) at 1154 A. These beam-foil measurements represent the most comprehensive and precise…
We present the results of lifetime measurements made using beam-foil techniques on levels of astrophysical interest in Pb II producing lines at 1203.6 A ($6s6p^{2}$ $^{2}D_{3/2}$) and 1433.9 A ($6s^{2}6d$ $^{2}D_{3/2}$). We also report the…
We present lifetime measurements using beam-foil techniques for radiative transitions from the 3$p^4$($^1S$)4$s$ $^2S_{1/2}$, 3$p^4$($^3P$)5$s$ $^2P_{1/2,3/2}$, and 3$p^4$($^3P$)3$d$ $^2F_{5/2}$ levels in Cl I and the corresponding results…
Lifetime measurements using beam foil techniques for the $5s5p^{2}$ $^{2}D_{3/2,5/2}$ levels in Sn II are presented. The resulting oscillator strengths for transitions at 1699.4, 1831.8 and 1811.2 \AA{} are reported. We also studied these…
The stellar abundance ratio of Mg/Fe is an important tool in diagnostics of galaxy evolution. In order to make reliable measurements of the Mg abundance of stars, it is necessary to have accurate values for the oscillator strength (f-value)…
This work reports new experimental radiative lifetimes and calculated oscillator strengths for transitions of astrophysical interest in singly ionized cobalt. More precisely, nineteen radiative lifetimes in Co+ have been measured with the…
Phosphorus abundance is crucial for DNA-based extraterrestrial life in exoplanets. Atomic data for observed spectral lines of P-ions are needed for its accurate determination. We present the first calculations for collision strengths for…
We report empirical determinations of atomic oscillator strengths, or f-values, for 11 ground-state transitions of Fe II in the wavelength range 1050 to 1150 Ang. We use ultraviolet absorption line observations of interstellar material…
We report experimental oscillator strengths for 88 Ti I transitions covering the wavelength range 465 to 3892 nm, 67 of which had no previous experimental values. Radiative lifetimes for thirteen energy levels, including the low energy…
The lifetimes of 17 even-parity levels (3d5s, 3d4d, 3d6s, and 4p$^2$) in the region 57743-77837 cm$^{-1}$ of singly ionised scandium (\ion{Sc}{ii}) were measured by two-step time-resolved laser induced fluorescence spectroscopy. Oscillator…
This work reports new experimental radiative lifetimes and calculated oscillator strengths for transitions from 3d8 4d levels of astrophysical interest in singly ionized nickel. Radiative lifetimes of seven high-lying levels of even parity…
We report new experimental Fe I oscillator strengths obtained by combining measurements of branching fractions measured with a Fourier Transform spectrometer and time-resolved laser-induced fluorescence lifetimes. The study covers the…
Absorption oscillator strengths have been determined from high-resolution spectra in the 967-972 \AA region of three CO isotopomers for transitions to the Rydberg levels 4{\it p$\pi$}(0), 3{\it d$\pi$}(1) and 4{\it p$\sigma$}(0), as well as…
Band oscillator strengths for electronic transitions in CO were obtained at the Synchrotron Radiation Center of the University of Wisconsin-Madison. Our focus was on transitions that are observed in interstellar spectra with the Far…
The oscillator strengths of the $H^+_2$ molecular ion, $1s\sigma_{g}-2p\sigma_{u}$, $1s\sigma_{g}-2p\pi_{u}$ are calculated within the Born-Oppenheimer approximation. The variational expansion with randomly chosen exponents has been used…
Fully relativistic calculations have been performed for two multiplets, $3s3p^2\;^4P$ and $3s3p4s\;^4P^o$, in Al I. Wave functions were obtained for all levels of these multiplets using the GRASP programs. Reported are the E1 transitions…
Radiative lifetimes, accurate to +/- 5%, have been measured for 212 odd-parity levels of Sm II using laser-induced fluorescence. The lifetimes are combined with branching fractions measured using Fourier-transform spectrometry to determine…
Employing two state-of-the-art methods, multiconfiguration Dirac--Hartree--Fock and second-order many-body perturbation theory, the excitation energies and lifetimes for the lowest 200 states of the $2s^2 2p^4$, $2s 2p^5$, $2p^6$, $2s^2…
Employing two state-of-the-art methods, second-order many-body perturbation theory and multiconfiguration Dirac-Fock, highly accurate calculations are performed for the lowest 318 fine-structure levels arising from the $2s^{2} 2p^{4}$, $2s…
New branching fraction measurements based primarily on data from a cross dispersed echelle spectrometer are reported for 84 lines of Co II. The branching fractions for 82 lines are converted to absolute atomic transition probabilities using…