EDP Sciences
Free Access
Issue
A&A
Volume 420, Number 2, June III 2004
Page(s) 673 - 681
Section Stellar atmospheres
DOI https://doi.org/10.1051/0004-6361:20035651
Published online 28 May 2004


A&A 420, 673-681 (2004)
DOI: 10.1051/0004-6361:20035651

Chemical composition of the magnetic B star HR 5049

M. Nishimura1, K. Sadakane2, K. Kato3, Y. Takeda4 and G. Mathys5

1  Rakutou High School, Anshu, Yamashina-ku, Kyoto 607-8017, Japan
2  Astronomical Institute, Osaka Kyoiku University, Asahigaoka, Kashiwara, Osaka 582-8582, Japan
3  Osaka Science Museum, Nakanoshima, Kita-ku, Osaka 530-0005, Japan
4  National Astronomical Observatory, Osawa, Mitaka, Tokyo 181-8588, Japan
5  European Southern Observatory, Casilla 19001, Santiago 19, Chile

(Received 10 November 2003 / Accepted 23 February 2004)

Abstract
A spectrum synthesis analysis for photospheric lines in the magnetic B star HR 5049 is presented, based on a high quality spectrogram obtained with the EMMI spectrograph attached to the NTT at ESO. It is found that light elements such as He, C and O are under-abundant. One of the most notable features is the deficiency of He by more than -2.0 dex. Co and Cl are over-abundant by +3.5 dex and +1.9 dex, respectively. Other iron peak elements are over-abundant ranging from +0.47 dex ( $\ion{Ti}{ii}$) to +1.94 dex ( $\ion{Cr}{i}$). For rare earth elements, the lines of once-ionized species are generally weak, while the third spectra (especially those of Pr and Nd) are very prominent. Although rare earth elements show significant over-abundances ranging from +3.0 dex to as large as +4.0 dex, Ba has the solar abundance. The Nd-Pr abundance difference, which shows an apparent decreasing trend with increasing effective temperature among CP stars, is found to be unusually small in HR 5049.


Key words: stars: abundances -- stars: chemically peculiar -- stars: individual: HR 5049

Offprint request: M. Nishimura, mnisimura@kcat.zaq.ne.jp

SIMBAD Objects
Tables at the CDS



© 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.