Elemental Abundance Analyses with DAO Spectrograms. XXXIX. The Am Stars 2 UMa and 15 Vul

• Published in: Publications of the Astronomical Society of the Pacific Vol. 128; no. 963; pp. 1 - 8
• Main Authors: Çay, pek H., Yelkenci, Aysegul Teker, Adelman, Saul J.
• Format: Journal Article
• Language: English
• Published: The Astronomical Society of the Pacific 01.05.2016; IOP Publishing Limited
• Subjects: Stars and Stellar Evolution; stars: abundances; stars: chemically peculiar
• ISSN: 0004-6280; 1538-3873
• DOI: 10.1088/1538-3873/128/963/054201

We derived the elemental abundances of the metallic-line stars 2 UMa (=HR 3354; spectral type A2m) and 15 Vul (=HR 7653; spectral type A4 III), using high-dispersion, high signal-to-noise ratio (≥200) optical region spectrograms obtained with CCD detectors at the long Coudé camera of the 1.22 m telescope of the Dominion Astrophysical Observatory (DAO) and Kurucz's ATLAS9 and WIDTH9 programs. The star 2 UMa has not been the subject of a modern detailed elemental abundances analysis. It is relatively sharp-lined and sufficiently hot (Teff = 8050 K) that the continuum placement is not a major problem in the optical region. Comparison of the results of this new study of 15 Vul with the last complete study shows a 0.15 dex mean increase in the derived abundances and a reduction in the standard deviations of the mean values. The abundance anomalies of 2 UMa are usually larger than those of 15 Vul. The greater spectral coverage of 15 Vul compared with 2 UMa results in a larger number of abundances being derived. The abundances of 2 UMa are typical for those of classical Am stars that have similar effective temperatures and surface gravities. 15 Vul, characterized by a similar effective temperature and smaller surface gravity, is a more evolved star.