KEPLER-15b: A HOT JUPITER ENRICHED IN HEAVY ELEMENTS AND THE FIRST KEPLER MISSION PLANET CONFIRMED WITH THE HOBBY-EBERLY TELESCOPE

Journal Article · Tue Nov 01 00:00:00 EDT 2011 · Astrophysical Journal, Supplement Series

DOI:https://doi.org/10.1088/0067-0049/197/1/13· OSTI ID:22047341

Endl, Michael; MacQueen, Phillip J; Cochran, William D ^[1]; Brugamyer, Erik J ^[2]; Buchhave, Lars A ^[3]; Rowe, Jason ^[4]; Lucas, Phillip ^[5]; Isaacson, Howard ^[6]; Bryson, Steve; Howell, Steve B; Borucki, William J; Caldwell, Douglas; Christiansen, Jessie L; Haas, Michael R ^[7]; Fortney, Jonathan J ^[8]; Hansen, Terese ^[9]; Ciardi, David R ^[10]; Demory, Brice-Olivier ^[11]; Everett, Mark ^[12]; Ford, Eric B ^[13] ; others, and

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1. McDonald Observatory, University of Texas at Austin, Austin, TX 78712 (United States)
2. Astronomy Department, University of Texas at Austin, Austin, TX 78712 (United States)
3. Niels Bohr Institute, University of Copenhagen, Denmark Centre for Star and Planet Formation, University of Copenhagen (Denmark)
4. SETI Institute, Moffett Field, CA 94035 (United States)
5. Centre for Astrophysics Research, University of Hertfordshire, College Lane, Hatfield AL10 9AB (United Kingdom)
6. Department of Astronomy, University of California, Berkeley, CA 94720 (United States)
7. NASA-Ames Research Center, Moffett Field, CA 94035 (United States)
8. Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)
9. Niels Bohr Institute, University of Copenhagen (Denmark)
10. NASA Exoplanet Science Institute/Caltech, Pasadena, CA 91125 (United States)
11. Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)
12. NOAO, 950 N. Cherry Ave., Tucson, AZ 85719 (United States)
13. Astronomy Department, University of Florida, 211 Bryant Space Sciences Center, Gainesville, FL 32111 (United States)

We report the discovery of Kepler-15b (KOI-128), a new transiting exoplanet detected by NASA's Kepler mission. The transit signal with a period of 4.94 days was detected in the quarter 1 (Q1) Kepler photometry. For the first time, we have used the High Resolution Spectrograph (HRS) at the Hobby-Eberly Telescope (HET) to determine the mass of a Kepler planet via precise radial velocity (RV) measurements. The 24 HET/HRS RVs and 6 additional measurements from the Fibre-fed Echelle Spectrograph spectrograph at the Nordic Optical Telescope reveal a Doppler signal with the same period and phase as the transit ephemeris. We used one HET/HRS spectrum of Kepler-15 taken without the iodine cell to determine accurate stellar parameters. The host star is a metal-rich ([Fe/H] = 0.36 {+-} 0.07) G-type main-sequence star with T{sub eff} = 5515 {+-} 124 K. The semi-amplitude K of the RV orbit is 78.7{sup +8.5}{sub -9.5} m s{sup -1}, which yields a planet mass of 0.66 {+-} 0.1 M{sub Jup}. The planet has a radius of 0.96 {+-} 0.06 R{sub Jup} and a mean bulk density of 0.9 {+-} 0.2 g cm{sup -3}. The radius of Kepler-15b is smaller than the majority of transiting planets with similar mass and irradiation level. This suggests that the planet is more enriched in heavy elements than most other transiting giant planets. For Kepler-15b we estimate a heavy element mass of 30-40 M{sub Circled-Plus }.

• OSTI ID: 22047341
• Journal Information: Astrophysical Journal, Supplement Series, Vol. 197, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0067-0049
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
AMPLITUDES
ASTROPHYSICS
BULK DENSITY
DOPPLER EFFECT
FIBERS
IMAGE PROCESSING
MAIN SEQUENCE STARS
MASS
METALS
ORBITS
PHOTOMETRY
PLANETS
RADIAL VELOCITY
RESOLUTION
TELESCOPES