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arXiv · 1004.2458

Search for Outer Massive Bodies around Transiting Planetary Systems: Candidates of Faint Stellar Companions around HAT-P-7

Norio Narita·Tomoyuki Kudo·Carolina Bergfors·Makiko Nagasawa·Christian Thalmann·Bun'ei Sato·Ryuji Suzuki·Ryo Kandori·Markus Janson·Miwa Goto·Wolfgang Brandner·Shigeru Ida·Lyu Abe·Joseph Carson·Sebastian E. Egner·Markus Feldt·Taras Golota·Olivier Guyon·Jun Hashimoto·Yutaka Hayano·Masahiko Hayashi·Saeko S. Hayashi·Thomas Henning·Klaus W. Hodapp·Miki Ishii·Gillian R. Knapp·Nobuhiko Kusakabe·Masayuki Kuzuhara·Taro Matsuo·Michael W. McElwain·Shoken Miyama·Jun-Ichi Morino·Amaya Moro-Martin·Tetsuo Nishimura·Tae-Soo Pyo·Eugene Serabyn·Takuya Suenaga·Hiroshi Suto·Yasuhiro Takahashi·Michihiro Takami·Naruhisa Takato·Hiroshi Terada·Daigo Tomono·Edwin L. Turner·Makoto Watanabe·Toru Yamada·Hideki Takami·Tomonori Usuda·Motohide Tamura
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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.

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Norio Narita, Tomoyuki Kudo, Carolina Bergfors, Makiko Nagasawa, Christian Thalmann, Bun'ei Sato, Ryuji Suzuki, Ryo Kandori, Markus Janson, Miwa Goto, Wolfgang Brandner, Shigeru Ida, Lyu Abe, Joseph Carson, Sebastian E. Egner, Markus Feldt, Taras Golota, Olivier Guyon, Jun Hashimoto, Yutaka Hayano, Masahiko Hayashi, Saeko S. Hayashi, Thomas Henning, Klaus W. Hodapp, Miki Ishii, Gillian R. Knapp, Nobuhiko Kusakabe, Masayuki Kuzuhara, Taro Matsuo, Michael W. McElwain, Shoken Miyama, Jun-Ichi Morino, Amaya Moro-Martin, Tetsuo Nishimura, Tae-Soo Pyo, Eugene Serabyn, Takuya Suenaga, Hiroshi Suto, Yasuhiro Takahashi, Michihiro Takami, Naruhisa Takato, Hiroshi Terada, Daigo Tomono, Edwin L. Turner, Makoto Watanabe, Toru Yamada, Hideki Takami, Tomonori Usuda, Motohide Tamura. 2010-04-14. Search for Outer Massive Bodies around Transiting Planetary Systems: Candidates of Faint Stellar Companions around HAT-P-7. https://doi.org/10.1093/pasj%2F62.3.779

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