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The Abundances of Vega from the Ultraviolet Spectrum

Published online by Cambridge University Press:  12 April 2016

Fiorella Castelli
Fiorella Castelli*
Affiliation:
CNR-GNA c/o Osservatorio Astronomico Via G.B. Tiepolo 11 - 34131 Trieste -Italy

Abstract

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We derived preliminary abundances from the ultraviolet spectrum of Vega by comparing high-resolution Copernicus spectra with spectra computed with the ATLAS9 code and with updated line lists. The Teff=9400 K, log g=3.90 model, which fits the visual flux and the Balmer profiles is able to fit the ultraviolet flux either with [M/H]=−l and microturbulent velocity ξ= 2 km s−1 or with [M/H]=−0.5 and ξ=0 km s−1. The line spectrum is fitted by ξ=2 ± 0.5 km s−1 and by an iron abundance log (N(Fe)/Ntot)=−5.2 ±0.1 dex. All the observed elements indicate underabundances ranging from about −0.35 dex (C ) up to about −1 dex (Ni, Zn). The origin of the underabundances is an open question.

Type
II. Atmospheres, a window to the interior
Information
International Astronomical Union Colloquium , Volume 137: Inside the Stars , 1993 , pp. 202 - 204
Copyright
Copyright © Astronomical Society of the Pacific 1993

References

Adelman, S.J., and Gulliver, A.F. 1990, Ap.J., 348, 712.CrossRefGoogle Scholar
Anders, E., and Grevesse, N. 1989, Geochim. Cosmochim. Acta 52, 197.CrossRefGoogle Scholar
Bohlin, R.C., Harris, A.W., Holm, A.V., Gry, C. 1990, Ap.J. Suppl., 73, 413.CrossRefGoogle Scholar
Charbonneau, P. 1991, Ap. J. (Letters), 212, L33.CrossRefGoogle Scholar
Cowley, C.R. 1991, IAU Symp. No 145, p. 183.Google Scholar
Gray, D.F. 1980, Pub. A. S. P, 92, 154.CrossRefGoogle Scholar
Grevesse, N. 1991, quoted as private communication by Iglesias, C.A., Rogers, F.J., and Wilson, B.G. in Spin-Orbit Interaction Effects on the Rosseland Mean Opacity, 1992, Ap.J., preprint.Google Scholar
Kumcz, R.L. 1989, line lists on magnetic tapesGoogle Scholar
Kurucz, R.L. 1991, New Opacity Calculations in Stellar Atmospheres beyond classical models, ed. Crivellari, et al., NATO ASI Series, p. 441.CrossRefGoogle Scholar
Kurucz, R.L. 1992, New atmospheres for modeling binaries and disks, to be publised in Improvements in Light Curve Modeling of Eclipsing Binary Stars, Berlin, Springer- Verlag.Google Scholar
Michaud, G. 1980, Astron. J., 85, 589.CrossRefGoogle Scholar
Rogerson, J.B. Jr., 1989, Ap. J. Suppl., 71, 1011.CrossRefGoogle Scholar
Venn, K.A., and Lambert, D.L. 1990, Ap.J. Suppl., 363, 234.Google Scholar
Waters, L.B.F.M., Trams, N.R., Waelkens, C. 1992, Astr. Ap., preprint.Google Scholar