ABUNDANCE ANALYSIS OF ROAP STARS .1. ALPHA-CIRCINI

Citation
F. Kupka et al., ABUNDANCE ANALYSIS OF ROAP STARS .1. ALPHA-CIRCINI, Astronomy and astrophysics, 308(3), 1996, pp. 886-894
Citations number
43
Categorie Soggetti
Astronomy & Astrophysics
Journal title
ISSN journal
00046361
Volume
308
Issue
3
Year of publication
1996
Pages
886 - 894
Database
ISI
SICI code
0004-6361(1996)308:3<886:AAORS.>2.0.ZU;2-V
Abstract
Based on high resolution, low noise spectroscopy in the spectral regio n from 4200 Angstrom to 6700 Angstrom we derived T-eff = 7900 +/- 200 K, log g = 4.2 +/- 0.15, nu sin(i) = 12.5 (-0.5, + 1.5)km s(-1), and e lemental abundances for the rapidly oscillating (ro)Ap star alpha Cir( HD 128898, HR5463). We used the spectrum synthesis and the equivalent width technique and confirmed the presence of a magnetic field in alph a Cir. The underabundance of C, N, and O, and the overabundances of ra re-earth and some other heavy elements are comparable to other cool Ap -stars. The most important peculiarity is that of Co, which is almost as overabundant as Cr, the most overabundant iron peak element in cool Ap-stars.