CAOSP abstracts, Volume: 27, No.: 3, year: 1998
- Author(s): PAUNZEN, E.
- Journal: Contributions of the Astronomical Observatory Skalnate Pleso,
vol. 27, no. 3, p. 479-481.
- Date: 04/1998
- Title: On the evolutionary status of lambda Bbootis stars using Hipparcos data
- Keyword(s): STARS: LAMBDA BOOTIS, STARS: CHEMICALLY PECULIAR, STARS: EARLY TYPE,
STARS: FUNDAMENTAL PARAMETERS, STARS: PRE-MAIN SEQUENCE
- Pages: 479 -- 481
Using the Hipparcos data, absolute magnitudes and thus the evolutionary
status for the group of lambda Bootis stars were derived. The origin of this
small group of non-magnetic, chemically peculiar stars, still remains
a matter of debate. Using new evolutionary tracks, an age determination
could be provided to distinguish between the two competing theories - the
diffusion/mass-loss and the accretion. The results establish the members of
this group as objects which are very close to the Main Sequence. This is
supported by Pre-Main Sequence evolutionary tracks as well as by
observational results. This contradicts prior conclusions that most of these
stars are in the middle of their Main Sequence lifetime. The new results
strongly support the predictions of the accretion theory.
Full text version of this article in
(600dpi) format compressed by gzip; or in