Issue |
A&A
Volume 418, Number 3, May II 2004
|
|
---|---|---|
Page(s) | 1073 - 1081 | |
Section | Stellar structure and evolution | |
DOI | https://doi.org/10.1051/0004-6361:20034257 | |
Published online | 16 April 2004 |
Emission lines in the optical spectrum of 3 Cen A *,**
1
Lund Observatory, University of Lund, Box 43, 22100 Lund, Sweden
2
European Southern Observatory, Casilla 19001, Santiago 19, Chile e-mail: shubrig@eso.org
Corresponding author: G. M. Wahlgren, glenn.wahlgren@astro.lu.se
Received:
2
September
2003
Accepted:
10
February
2004
Previously, weak emission lines had been detected at red wavelengths in the spectra of a limited sample of mid to late B type main sequence stars. A fuller description of the occurrence and origins of these lines has yet to be forwarded, in part due to the lack of observations detailing the spectral transitions involved. To address this deficiency, we present a line list of weak emission features found in the optical and near infrared spectral region of the chemically peculiar He-weak star 3 Cen A (HD 120709). Nearly 350 features, mostly associated with allowed transitions from high-excitation states of first ions, are catalogued along with identifications. Prominent among the emission lines are the spectra P II, Mn II, Fe II, Ni II and Cu II. Emission lines from Ca II, Si II and Hg II are also evident. Abundances are determined for several elements from synthetic spectrum fitting, with anomalies detected for the ions O I/II, P II/III and Si II/III. The LTE synthetic spectrum fitting also revealed that the low excitation 4s-4p transitions of Fe II predict an abundance that is greater than that determined from higher excitation 4d-4f transitions. Several of these latter transitions have upper energy levels that are found to be associated with emission lines. We also present empirical considerations for the excitation processes leading to the weak emission lines.
Key words: line: identification / stars: abundances / stars: chemically peculiar / stars: emission / stars: individual: 3 Cen A
© ESO, 2004
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.