Astronomy and Astrophysics – Astrophysics
Scientific paper
2002-07-23
Mon.Not.Roy.Astron.Soc. 336 (2002) 1030
Astronomy and Astrophysics
Astrophysics
14 pages, 9 figures, accepted by MNRAS
Scientific paper
10.1046/j.1365-8711.2002.05865.x
The lambda Bootis stars are Population I, late B to early F-type stars, with 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). To put constraints on the various existing theories that try to explain these peculiar stars, we investigate the observational properties of lambda Bootis stars compared to a reference sample of normal stars. Using various photometric systems and Hipparcos data, we analyze the validity of standard photometric calibrations, elemental abundances, and Galactic space motions. There crystallizes a clear picture of a homogeneous group of Population I objects found at all stages of their main-sequence evolution, with a peak at about 1 Gyr. No correlation of astrophysical parameters such as the projected rotational velocities or elemental abundances with age is found, suggesting that the a-priori unknown mechanism, which creates lambda Bootis stars, works continuously for late B to early F-type stars in all stages of main-sequence evolution. Surprisingly, the sodium abundances seem to indicate an interaction between the stars and their local environment.
Barzova Ina S.
Iliev Ilian Kh.
Kamp Inga
Paunzen E. E.
No associations
LandOfFree
The status of Galactic field lambda Bootis stars in the post-Hipparcos era does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The status of Galactic field lambda Bootis stars in the post-Hipparcos era, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The status of Galactic field lambda Bootis stars in the post-Hipparcos era will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-468917