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Atomic Transition Probabilities of Aluminum and Silicon A Critical Compilation



Daniel E. Kelleher, Larissa Podobedova


This compilation is the second in a series of updates to Atomic Transition Probabilities, Sodium through Calcium, published in 19691. Atomic transition probabilities have been critically evaluated and compiled for about 10,800 spectral lines of aluminum and silicon (nuclear charge Z = 13-14). The cited values and their estimated uncertainties are based on our consideration of all available theoretical and experimental literature sources. All ionization stages (except for hydrogenic) are covered, and the data are presented in separate tables for each atom and ion. Separate listings are given for allowed (electric dipole) and forbidden (magnetic dipole plus electric and magnetic quadrupole) transitions. In each spectrum, lines are grouped into multiplets which are arranged in order of ascending lower and upper level energies, respectively. For each line, the emission transition probability Aki, the line strength S, and (for allowed lines) the absorption oscillator strength fik, are given together with the spectroscopic designation, the wavelength, the statistical weights, and the energy levels of the lower and upper states. The estimated relative uncertainties of the line strength are also indicated, as are the source citations. The statistical method we use to estimate these uncertainties is described in detail. We only include those lines whose transition rates are deemed sufficiently accurate to qualify as reference values. A discussion of the principal criteria for our judgments and our method of data selection and evaluation are presented in ref. 4. Short introductions precede the tables for each ion.
J. Phys. & Chem. Ref. Data (JPCRD) -


atomic spectra, energy levels, ions, line strengths, magnesium, oscillator strengths, sodium, transition probabilities


Kelleher, D. and Podobedova, L. (2018), Atomic Transition Probabilities of Aluminum and Silicon A Critical Compilation, J. Phys. & Chem. Ref. Data (JPCRD), National Institute of Standards and Technology, Gaithersburg, MD (Accessed May 28, 2024)


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Created November 14, 2018