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arXiv · astro-ph/0206143

Abundance analysis of two late A-type stars HD 32115 and HD 37594

Abstract

We have performed abundance analysis of two slowly rotating, late A-type stars, HD 32115 (HR 1613) and HD 37594 (HR 1940), based on obtained echelle spectra covering the spectral range 4000-9850 AAngstrom. These spectra allowed us to identify an extensive line list for 31 chemical elements, the most complete to date for A-type stars. Two approaches to abundance analysis were used, namely a ``manual'' (interactive) and a semi-automatic procedure for comparison of synthetic and observed spectra and equivalent widths. For some elements non-LTE (NLTE) calculations were carried out and the corresponding corrections have been applied. The abundance pattern of HD 32115 was found to be very close to the solar abundance pattern, and thus may be used as an abundance standard for chemical composition studies in middle and late A stars. Further, its H-alpha line profile shows no core-to-wing anomaly like that found for cool Ap stars and therefore also may be used as a standard in comparative studies of the atmospheric structures of cool, slowly rotating Ap stars. HD 37594 shows a metal deficiency at the level of -0.3 dex for most elements and triangle-like cores of spectral lines. This star most probably belongs to the Delta Scuti group.

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I. F. Bikmaev, T. A. Ryabchikova, H. Bruntt, F. A. Musaev, L. I. Mashonkina, E. V. Belyakova, V. V. Shimansky, P. S. Barklem, G. Galazutdinov. 2002-06-10. Abundance analysis of two late A-type stars HD 32115 and HD 37594. https://doi.org/10.1051/0004-6361%3A20020593

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