A Common Proper Motion Stellar Companion to HAT-P-7
Earth and Planetary Astrophysics
2015-06-11 v1 Solar and Stellar Astrophysics
Abstract
We report that HAT-P-7 has a common proper motion stellar companion. The companion is located at arcsec to the east and estimated as an M5.5V dwarf based on its colors. We also confirm the presence of the third companion, which was first reported by Winn et al. (2009), based on long-term radial velocity measurements. We revisit the migration mechanism of HAT-P-7b given the presence of those companions, and propose sequential Kozai migration as a likely scenario in this system. This scenario may explain the reason for an outlier in the discussion of the spin-orbit alignment timescale for HAT-P-7b by Albrecht et al. (2012).
Keywords
Cite
@article{arxiv.1209.4422,
title = {A Common Proper Motion Stellar Companion to HAT-P-7},
author = {Norio Narita and Yasuhiro H. Takahashi and Masayuki Kuzuhara and Teruyuki Hirano and Takuya Suenaga and Ryo Kandori and Tomoyuki Kudo and Bun'ei Sato and Ryuji Suzuki and Shigeru Ida and Makiko Nagasawa and Lyu Abe and Wolfgang Brandner and Timothy D. Brandt and Joseph Carson and Sebastian E. Egner and Markus Feldt and Miwa Goto and Carol A. Grady and Olivier Guyon and Jun Hashimoto and Yutaka Hayano and Masahiko Hayashi and Saeko S. Hayashi and Thomas Henning and Klaus W. Hodapp and Miki Ishii and Masanori Iye and Markus Janson and Gillian R. Knapp and Nobuhiko Kusakabe and Jungmi Kwon and Taro Matsuo and Satoshi Mayama and Michael W. McElwain and Shoken Miyama and Jun-Ichi Morino and Amaya Moro-Martin and Tetsuo Nishimura and Tae-Soo Pyo and Eugene Serabyn and Hiroshi Suto and Michihiro Takami and Naruhisa Takato and Hiroshi Terada and Christian Thalmann and Daigo Tomono and Edwin L. Turner and Makoto Watanab and John P. Wisniewski and Toru Yamada and Hideki Takami and Tomonori Usuda and Motohide Tamara},
journal= {arXiv preprint arXiv:1209.4422},
year = {2015}
}
Comments
5 pages, 4 figures, 2 tables, PASJ Letters in press