Search for Outer Massive Bodies around Transiting Planetary Systems: Candidates of Faint Stellar Companions around HAT-P-7
/ Authors
N. Narita, T. Kudo, C. Bergfors, M. Nagasawa, C. Thalmann, B. Sato, R. Suzuki, R. Kandori, M. Janson, M. Goto
and 39 more authors
W. Brandner, S. Ida, L. Abe, J. Carson, S. Egner, M. Feldt, T. Golota, O. Guyon, J. Hashimoto, Y. Hayano, M. Hayashi, S. Hayashi, T. Henning, K. Hodapp, M. Ishii, G. Knapp, N. Kusakabe, M. Kuzuhara, T. Matsuo, M. McElwain, S. Miyama, J. Morino, A. Moro-Martin, T. Nishimura, T. Pyo, E. Serabyn, T. Suenaga, H. Suto, Yasuhiro H. Takahashi, M. Takami, N. Takato, H. Terada, D. Tomono, E. Turner, Makoto Watanabe, Toru Yamada, H. Takami, T. Usuda, M. Tamura
/ Abstract
We present results of direct imaging observations for HAT-P-7 taken with the Subaru HiCIAO and the Calar Alto AstraLux. Since the close-in transiting planet HAT-P-7b was reported to have a highly tilted orbit, massive bodies such as giant planets, brown dwarfs, or a binary star are expected to exist in the outer region of this system. We show that there are indeed two candidates for distant faint stellar companions around HAT-P-7. We discuss possible roles played by such companions on the orbital evolution of HAT-P-7b. We conclude that as there is a third body in the system as reported by Winn et al. (2009, ApJL, 763, L99), the Kozai migration is less likely while planet-planet scattering is possible.
Journal: arXiv: Earth and Planetary Astrophysics