Volume 537, January 2012
|Number of page(s)||8|
|Section||Stellar structure and evolution|
|Published online||17 January 2012|
1 Astronomical Institute, Faculty of Mathematics and Physics, Charles University Prague, CZ-180 00 Praha 8, V Holešovičkách 2, Czech Republic
2 Private observatory, Výpustky 5, Brno 614 00, Czech Republic
3 Private Observatory, Pohoří 71, 25401 Jílové u Prahy, Czech Republic
Received: 6 June 2011
Accepted: 9 December 2011
Context. A study of late-type low-mass eclipsing binaries provides us with important information about the most common stars in the Universe.
Aims. We obtain the first light curves and perform period analyses of two neglected eclipsing binaries GK Boo and AE For to reveal their basic physical properties.
Methods. We performed both a period analysis of the times of the minima and a BVR light curve analysis. Many new times of minima for both the systems were derived and collected from the data obtained by automatic and robotic telescopes. This allowed us to study the long-term period changes in these systems for the first time. From the light curve analysis, we derived the first rough estimates of the physical properties of these systems.
Results. We find that the analyzed systems are somewhat similar to each other. Both contain low-mass components of similar types, both are close to the Sun, both have short orbital period, and both contain another low-mass companions on longer orbits of a few years. In the case of GK Boo, both components are probably of K3 spectral type, while the distant companion is probably a late M star. The light curve of GK Boo is asymmetric, which probably causes the shift in the secondary minima in the O − C diagram. System AE For comprises two K7 stars, and the third body is a possible brown dwarf with a minimal mass of only about 47 MJup.
Conclusions. We succeed in completing period and light curve analyses of both systems, although a more detailed spectroscopic analysis is needed to confirm the physical parameters of the components to a higher accuracy.
Key words: binaries: eclipsing / stars: fundamental parameters / stars: individual: GK Boo / stars: individual: AE For
Tables 8 and 9 are available in electronic form at http://www.aanda.org
© ESO, 2012
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.