Volume 400, Number 1, March II 2003
|Page(s)||271 - 277|
|Section||Stellar structure and evolution|
|Published online||24 February 2003|
Dr.-Remeis-Sternwarte, Sternwartstraße 7, 96049 Bamberg, Germany
2 Institut für Astronomie und Astrophysik, Abteilung Astronomie, Sand 1, 72076 Tübingen, Germany
Corresponding author: T. Rauch, firstname.lastname@example.org
Accepted: 17 December 2002
We present an analysis of the rotational velocity of the primary of LB 3459 based on 107 new high-resolution and high- ESO VLT UVES spectra. 105 of them cover a complete orbital period (0.26 d) of this binary system. We have determined an orbital period of , a radial velocity amplitude of , and . From simulations of the He II λ 4686 Å line profile (based on NLTE model atmosphere calculations), we derive . We present an animation which shows the orbital movement of the binary system, its synthetic lightcurve, and compares the phase-dependent variation of the predicted with the observed He II λ 4686 Å line profile. The radius of the cool component is almost the same size like Jupiter but its mass is about 70 times higher than Jupiter's mass. Thus, from its present mass (), the secondary of LB 3459 lies formally within the brown-dwarf mass range (). It might be a former planet which has survived the previous common-envelope phase and even has gained mass.
Key words: stars: binaries: eclipsing / stars: fundamental parameters / stars: individual: LB 3459 / stars: individual: AA Dor / stars: low-mass, brown dwarfs / stars: rotation
© ESO, 2003
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.