FRIENDS OF HOT JUPITERS. III. AN INFRARED SPECTROSCOPIC SEARCH FOR LOW-MASS STELLAR COMPANIONS

Journal Article · Tue Dec 01 04:00:00 EST 2015 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/814/2/148· OSTI ID:22521834

Piskorz, Danielle; Knutson, Heather A.; Ngo, Henry; Batygin, Konstantin ^[1]; Muirhead, Philip S. ^[2]; Crepp, Justin R. ^[3]; Hinkley, Sasha ^[4]

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1. Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA (United States)
2. Institute for Astrophysical Research, Boston University, Boston, MA (United States)
3. Department of Physics, University of Notre Dame, South Bend, IN (United States)
4. Department of Physics and Astronomy, University of Exeter, Exeter (United Kingdom)

Surveys of nearby field stars indicate that stellar binaries are common, yet little is known about the effects that these companions may have on planet formation and evolution. The Friends of Hot Jupiters project uses three complementary techniques to search for stellar companions to known planet-hosting stars: radial velocity monitoring, adaptive optics imaging, and near-infrared spectroscopy. In this paper, we examine high-resolution K band infrared spectra of fifty stars hosting gas giant planets on short-period orbits. We use spectral fitting to search for blended lines due to the presence of cool stellar companions in the spectra of our target stars, where we are sensitive to companions with temperatures between 3500 and 5000 K and projected separations less than 100 AU in most systems. We identify eight systems with candidate low-mass companions, including one companion that was independently detected in our AO imaging survey. For systems with radial velocity accelerations, a spectroscopic non-detection rules out scenarios involving a stellar companion in a high inclination orbit. We use these data to place an upper limit on the stellar binary fraction at small projected separations, and show that the observed population of candidate companions is consistent with that of field stars and also with the population of wide-separation companions detected in our previous AO survey. We find no evidence that spectroscopic stellar companions are preferentially located in systems with short-period gas giant planets on eccentric and/or misaligned orbits.

• OSTI ID: 22521834
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 814; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ABSORPTION SPECTROSCOPY
ACCELERATION
BINARY STARS
DATA ANALYSIS
INCLINATION
INFRARED SPECTRA
JUPITER PLANET
MASS
NEAR INFRARED RADIATION
ORBITS
RADIAL VELOCITY
RESOLUTION
SATELLITES