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HD 181068: a red giant in a triply eclipsing compact hierarchical triple system
A Derekas1, L L Kiss, T Borkovits
1Department of Astronomy, Eötvös University, Budapest, Hungary. derekas@konkoly.hu
Science (New York, N.Y.)
|April 9, 2011
Summary
Hierarchical triple systems, like HD 181068, are key to understanding star evolution. This study reveals a red giant with tidally induced oscillations due to a close binary companion.
Area of Science:
- Astronomy and Astrophysics
- Stellar Physics
- Exoplanetary Systems
Background:
- Hierarchical triple systems are crucial for testing stellar formation and evolution theories.
- These systems consist of a close binary pair and a more distant stellar component.
Purpose of the Study:
- To analyze the hierarchical triple system HD 181068 using extensive photometric and spectroscopic data.
- To investigate the dynamical interactions and tidal effects within the system.
Main Methods:
- Acquisition of 218 days of Kepler photometry for HD 181068.
- Supplementation with ground-based spectroscopy and interferometry.
- Analysis of mutual eclipses to determine orbital parameters and system configuration.
Main Results:
- HD 181068 confirmed as a hierarchical triple system.
- The system comprises a red giant in a 45-day orbit with a close 0.9-day binary of red dwarfs.
- Evidence of tidally induced oscillations in the red giant, driven by the inner binary's motion.
Conclusions:
- HD 181068 serves as an ideal laboratory for studying dynamical evolution in triple star systems.
- The system provides a unique opportunity to test theories of tidal friction and stellar interactions.
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