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arXiv · 1002.2945

HD 65949: Rosetta Stone or Red Herring

C. R. Cowley·S. Hubrig·P. Palmeri·P. Quinet·É. Biémont·G. M. Wahlgren·O. Schütz·J. F. González
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Abstract

HD 65949 is a late B star with exceptionally strong Hg II at 3984[A], but it is not a typical HgMn star. The Re II spectrum is of extraordinary strength. Abundances, or upper limits are derived here for 58 elements based on a model with Teff = 13100K, and log(g) = 4.0. Even-Z elements through nickel show minor deviations from solar abundances. Anomalies among the odd-Z elements through copper are mostly small. Beyond the iron peak, a huge scatter is found. The abundance pattern of the heaviest elements resembles the N=126 r-process peak of solar material, though not in detail. We find a significant correlation of the abundance excesses with second ionization potentials for elements with Z > 30. This indicates the relevance of photospheric or near-photospheric processes. We explore a model with mass accretion of exotic material followed by the more commonly accepted differentiation by diffusion. That model leads to a number of predictions which challenge future work. Likely primary and secondary masses are near 3.3 and 1.6 M(solar), with a separation of ca. 0.25 AU. New atomic structure calculations are presented in two appendices.

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C. R. Cowley, S. Hubrig, P. Palmeri, P. Quinet, É. Biémont, G. M. Wahlgren, O. Schütz, J. F. González. 2010-02-15. HD 65949: Rosetta Stone or Red Herring. https://doi.org/10.1111/j.1365-2966.2010.16529.x

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