
The Library
HD 54272, a classical λ Bootis star and γ Doradus pulsator
Tools
Paunzen, E., Skarka, M., Holdsworth, D. L., Smalley, B. and West, Richard G. (2014) HD 54272, a classical λ Bootis star and γ Doradus pulsator. Monthly Notices of the Royal Astronomical Society, Volume 440 (Number 2). pp. 1020-1026. doi:10.1093/mnras/stu415
Research output not available from this repository, contact author.
Official URL: http://dx.doi.org/10.1093/mnras/stu415
Abstract
We detect the second known λ Bootis star (HD 54272) which exhibits γ Doradus-type pulsations. The star was formerly misidentified as a RR Lyrae variable. The λ Bootis stars are a small group (only 2 per cent) of late B to early F-type, Population I stars which show moderate to extreme (up to a factor 100) surface underabundances of most Fe-peak elements and solar abundances of lighter elements (C, N, O, and S). The photometric data from the Wide Angle Search for Planets (WASP) and All Sky Automated Survey (ASAS) projects were analysed. They have an overlapping time base of 1566 d and 2545 d, respectively. Six statistically significant peaks were identified (f1 = 1.410 116 d−1, f2 = 1.283 986 d−1, f3 = 1.293 210 d−1, f4 = 1.536 662 d−1, f5 = 1.157 22 d−1 and f6 = 0.226 57 d−1). The spacing between f1 and f2, f1 and f4, f5 and f2 is almost identical. Since the daily aliasing is very strong, the interpretation of frequency spectra is somewhat ambiguous. From spectroscopic data, we deduce a high rotational velocity (250 ± 25 km s−1) and a metal deficiency of about −0.8 to −1.1 dex compared to the Sun. A comparison with the similar star, HR 8799, results in analogous pulsational characteristics but widely different astrophysical parameters. Since both are λ Bootis-type stars, the main mechanism of this phenomenon, selective accretion, may severely influence γ Doradus-type pulsations.
Item Type: | Journal Article | ||||||||
---|---|---|---|---|---|---|---|---|---|
Divisions: | Faculty of Science > Physics | ||||||||
Journal or Publication Title: | Monthly Notices of the Royal Astronomical Society | ||||||||
Publisher: | Oxford University Press | ||||||||
ISSN: | 0035-8711 | ||||||||
Official Date: | 11 May 2014 | ||||||||
Dates: |
|
||||||||
Volume: | Volume 440 | ||||||||
Number: | Number 2 | ||||||||
Page Range: | pp. 1020-1026 | ||||||||
DOI: | 10.1093/mnras/stu415 | ||||||||
Status: | Peer Reviewed | ||||||||
Publication Status: | Published | ||||||||
Access rights to Published version: | Restricted or Subscription Access |
Request changes or add full text files to a record
Repository staff actions (login required)
![]() |
View Item |