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arXiv · 0802.0990

Re II and Other Exotic Spectra in HD 65949

C. R. Cowley·S. Hubrig·G. M. Wahlgren
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Abstract

Powerful astronomical spectra reveal an urgent need for additional work on atomic lines, levels, and oscillator strengths. The star HD 65949 provides some excellent examples of species rarely identified in stellar spectra. For example, the Re II spectrum is well developed, with 17 lines between 3731 and 4904 [A], attributed wholly or partially to Re II. Classifications and oscillator strengths are lacking for a number of these lines. The spectrum of Os II is well identified. Of 14 lines attributed wholly or partially to Os II, only one has an entry in the VALD database. We find strong evidence that Te II is present. There are NO Te II lines in the VALD database. Ru II is clearly present, but oscillator strengths for lines in the visual are lacking. There is excellent to marginal evidence for a number of less commonly identified species, including Kr II, Nb II, Sb II, Xe II, Pr III, Ho III, Au II, and Pt II (probably Pt-198), to be present in the spectrum of HD 65949. The line Hg II at 3984 [A] is of outstanding strength, and all three lines of Multiplet 1 of Hg I are present, even though the surface temperature of HD 65949 is relatively high. Finally, we present the case of an unidentified, 24 [mA], line at 3859.63 [A], which could be the same feature seen in magnetic CP stars. It is typically blended with a putative U II line used in cosmochronology.

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C. R. Cowley, S. Hubrig, G. M. Wahlgren. 2008-02-07. Re II and Other Exotic Spectra in HD 65949. https://doi.org/10.1088/1742-6596/130/1/012005

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