THE NEPTUNE-SIZED CIRCUMBINARY PLANET KEPLER-38b

Journal Article · Sat Oct 20 00:00:00 EDT 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/758/2/87· OSTI ID:22086536

Orosz, Jerome A; Welsh, William F; Short, Donald R; Windmiller, Gur ^[1]; Carter, Joshua A; Torres, Guillermo; Geary, John C ^[2]; Brugamyer, Erik; Cochran, William D; Endl, Michael; MacQueen, Phillip ^[3]; Buchhave, Lars A ^[4]; Ford, Eric B ^[5]; Agol, Eric ^[6]; Barclay, Thomas; Caldwell, Douglas A; Clarke, Bruce D ^[7]; Doyle, Laurance R ^[8]; Fabrycky, Daniel C ^[9]; Haghighipour, Nader ^[10] ; others, and

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1. Department of Astronomy, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182 (United States)
2. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
3. McDonald Observatory, University of Texas at Austin, Austin, TX 78712-0259 (United States)
4. Niels Bohr Institute, University of Copenhagen, Juliane Maries vej 30, DK-2100 Copenhagen (Denmark)
5. Astronomy Department, University of Florida, 211 Bryant Space Sciences Center, Gainesville, FL 32611 (United States)
6. Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States)
7. NASA Ames Research Center, Moffett Field, CA 94035 (United States)
8. SETI Institute, 189 Bernardo Avenue, Mountain View, CA 94043 (United States)
9. Department of Astronomy and Astrophysics, University of California, Santa Cruz, Santa Cruz, CA 95064 (United States)
10. Institute for Astronomy and NASA Astrobiology Institute University of Hawaii-Manoa, 2680 Woodlawn Dr., Honolulu, HI 96822 (United States)

We discuss the discovery and characterization of the circumbinary planet Kepler-38b. The stellar binary is single-lined, with a period of 18.8 days, and consists of a moderately evolved main-sequence star (M{sub A} = 0.949 {+-} 0.059 M {sub Sun} and R{sub A} = 1.757 {+-} 0.034 R {sub Sun }) paired with a low-mass star (M{sub B} = 0.249 {+-} 0.010 M {sub Sun} and R{sub B} = 0.2724 {+-} 0.0053 R {sub Sun }) in a mildly eccentric (e = 0.103) orbit. A total of eight transits due to a circumbinary planet crossing the primary star were identified in the Kepler light curve (using Kepler Quarters 1-11), from which a planetary period of 105.595 {+-} 0.053 days can be established. A photometric dynamical model fit to the radial velocity curve and Kepler light curve yields a planetary radius of 4.35 {+-} 0.11 R {sub Circled-Plus }, or equivalently 1.12 {+-} 0.03 R {sub Nep}. Since the planet is not sufficiently massive to observably alter the orbit of the binary from Keplerian motion, we can only place an upper limit on the mass of the planet of 122 M {sub Circled-Plus} (7.11 M {sub Nep} or equivalently 0.384 M {sub Jup}) at 95% confidence. This upper limit should decrease as more Kepler data become available.

• OSTI ID: 22086536
• Journal Information: Astrophysical Journal, Vol. 758, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ASTRONOMY
ASTROPHYSICS
BINARY STARS
DETECTION
DIAGRAMS
MAIN SEQUENCE STARS
MASS
ORBITS
RADIAL VELOCITY
SATELLITES
VISIBLE RADIATION