KNOW THE STAR, KNOW THE PLANET. V. CHARACTERIZATION OF THE STELLAR COMPANION TO THE EXOPLANET HOST STAR HD 177830

Journal Article · Thu Oct 15 00:00:00 EDT 2015 · Astronomical Journal (Online)

DOI:https://doi.org/10.1088/0004-6256/150/4/103· OSTI ID:22520139

Roberts, Jr., Lewis C.; Beichman, Charles; Burruss, Rick; Cady, Eric; Lockhart, Thomas G. ^[1]; Oppenheimer, Rebecca; Brenner, Douglas; Luszcz-Cook, Statia; Nilsson, Ricky ^[2]; Crepp, Justin R. ^[3]; Baranec, Christoph ^[4]; Dekany, Richard; Hillenbrand, Lynne ^[5]; Hinkley, Sasha ^[6]; King, David; Parry, Ian R. ^[7]; Pueyo, Laurent ^[8]; Sivaramakrishnan, Anand; Soummer, Rémi ^[9]; others, and

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1. Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena CA 91109 (United States)
2. American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024 (United States)
3. Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN 46556 (United States)
4. Institute for Astronomy, University of Hawai‘i at Mānoa, Hilo, HI 96720-2700 (United States)
5. Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States)
6. School of Physics, University of Exeter, Stocker Road, Exeter, EX4 4QL (United Kingdom)
7. Institute of Astronomy, University of Cambridge, Madingley Road., Cambridge, CB3 OHA (United Kingdom)
8. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
9. Department of Astronomy, Stockholm University, AlbaNova University Center, Roslagstullsbacken 21, SE-10691 Stockholm (Sweden)

HD 177830 is an evolved K0IV star with two known exoplanets. In addition to the planetary companions it has a late-type stellar companion discovered with adaptive optics imagery. We observed the binary star system with the PHARO near-IR camera and the Project 1640 coronagraph. Using the Project 1640 coronagraph and integral field spectrograph we extracted a spectrum of the stellar companion. This allowed us to determine that the spectral type of the stellar companion is a M4 ± 1 V. We used both instruments to measure the astrometry of the binary system. Combining these data with published data, we determined that the binary star has a likely period of approximately 800 years with a semimajor axis of 100–200 AU. This implies that the stellar companion has had little or no impact on the dynamics of the exoplanets. The astrometry of the system should continue to be monitored, but due to the slow nature of the system, observations can be made once every 5–10 years.

• OSTI ID: 22520139
• Journal Information: Astronomical Journal (Online), Vol. 150, Issue 4; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
BINARY STARS
CAMERAS
INTEGRALS
NEAR INFRARED RADIATION
OPTICS
PLANETS
STELLAR CORONAE