HAT-P-31b,c: A TRANSITING, ECCENTRIC, HOT JUPITER AND A LONG-PERIOD, MASSIVE THIRD BODY

Journal Article · Thu Sep 15 04:00:00 EDT 2011 · Astronomical Journal (New York, N.Y. Online)

DOI:https://doi.org/10.1088/0004-6256/142/3/95· OSTI ID:21582882

Kipping, D M; Hartman, J; Bakos, G A; Torres, G; Latham, D W; Beky, B; Quinn, S N; Noyes, R W; Sasselov, D D; Stefanik, R P ^[1]; Bayliss, D; Kiss, L L ^[2]; Sato, B ^[3]; Kovacs, Geza ^[4]; Buchhave, L A; Andersen, J ^[5]; Marcy, G W; Howard, A W ^[6]; Fischer, D A ^[7]

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1. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States)
2. Research School of Astronomy and Astrophysics, The Australian National University, Weston Creek, ACT (Australia)
3. Department of Earth and Planetary Sciences, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551 (Japan)
4. Konkoly Observatory, Budapest (Hungary)
5. Niels Bohr Institute, Copenhagen University, Copenhagen (Denmark)
6. Department of Astronomy, University of California, Berkeley, CA (United States)
7. Department of Astronomy, Yale University, New Haven, CT (United States)

We report the discovery of HAT-P-31b, a transiting exoplanet orbiting the V = 11.660 dwarf star GSC 2099-00908. HAT-P-31b is the first planet discovered with the Hungarian-made Automated Telescope (HAT) without any follow-up photometry, demonstrating the feasibility of a new mode of operation for the HATNet project. The 2.17 M{sub J} , 1.1 R{sub J} planet has a period of P{sub b} = 5.0054 days and maintains an unusually high eccentricity of e{sub b} = 0.2450 {+-} 0.0045, determined through Keck, FIbr-fed Echelle Spectrograph, and Subaru high-precision radial velocities (RVs). Detailed modeling of the RVs indicates an additional quadratic residual trend in the data detected to very high confidence. We interpret this trend as a long-period outer companion, HAT-P-31c, of minimum mass 3.4 M{sub J} and period {>=}2.8 years. Since current RVs span less than half an orbital period, we are unable to determine the properties of HAT-P-31c to high confidence. However, dynamical simulations of two possible configurations show that orbital stability is to be expected. Further, if HAT-P-31c has non-zero eccentricity, our simulations show that the eccentricity of HAT-P-31b is actively driven by the presence of c, making HAT-P-31 a potentially intriguing dynamical laboratory.

• OSTI ID: 21582882
• Journal Information: Astronomical Journal (New York, N.Y. Online), Journal Name: Astronomical Journal (New York, N.Y. Online) Journal Issue: 3 Vol. 142; ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
DWARF STARS
JUPITER PLANET
PHOTOMETRY
PLANETS
RADIAL VELOCITY
SIMULATION
STARS
TELESCOPES
VELOCITY