A. Derekas, L. L. Kiss, T. Borkovits, D. Huber, H. Lehmann, J. Southworth, T. R. Bedding, D. Balam, M. Hartmann, M. Hrudkova, M. J. Ireland, J. Kovacs, Gy. Mezo, A. Moor, E. Niemczura, G. E. Sarty, Gy. M. Szabo, R. Szabo, J. H. Telting, A. Tkachenko, K. Uytterhoeven, J. M. Benko, S. T. Bryson, V. Maestro, A. E. Simon, D. Stello, G. Schaefer, C. Aerts, T. A. ten Brummelaar, P. De Cat, H. A. McAlister, C. Maceroni, A. Merand, M. Still, J. Sturmann, L. Sturmann, N. Turner, P. G. Tuthill, J. Christensen-Dalsgaard, R. L. Gilliland, H. Kjeldsen, E. V. Quintana, P. Tenenbaum, J. D. Twicken
Hierarchical triple systems comprise a close binary and a more distant
component. They are important for testing theories of star formation and of
stellar evolution in the presence of nearby companions. We obtained 218 days of
Kepler photometry of HD 181068 (magnitude of 7.1), supplemented by groundbased
spectroscopy and interferometry, which show it to be a hierarchical triple with
two types of mutual eclipses. The primary is a red giant that is in a 45-day
orbit with a pair of red dwarfs in a close 0.9-day orbit. The red giant shows
evidence for tidally-induced oscillations that are driven by the orbital motion
of the close pair. HD 181068 is an ideal target for studies of dynamical
evolution and testing tidal friction theories in hierarchical triple systems.
View original:
http://arxiv.org/abs/1202.2196
No comments:
Post a Comment