CHARACTERIZING K2 PLANET DISCOVERIES: A SUPER-EARTH TRANSITING THE BRIGHT K DWARF HIP 116454

Journal Article · Tue Feb 10 00:00:00 EST 2015 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/800/1/59· OSTI ID:22364214

Vanderburg, Andrew; Montet, Benjamin T.; Johnson, John Asher; Buchhave, Lars A.; Zeng, Li; Latham, David W.; Angus, Ruth; Bieryla, Allyson; Charbonneau, David ^[1]; Pepe, Francesco; Udry, Stéphane; Lovis, Christophe ^[2]; Cameron, Andrew Collier ^[3]; Molinari, Emilio; Boschin, Walter ^[4]; Matthews, Jaymie M. ^[5]; Cameron, Chris ^[6]; Law, Nicholas ^[7]; Bowler, Brendan P. ^[8]; Baranec, Christoph ^[9] ; others, and

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1. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)
2. Observatoire Astronomique de l'Université de Genève, 51 chemin des Maillettes, CH-1290 Versoix (Switzerland)
3. SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, Fife KY16 9SS (United Kingdom)
4. INAF-Fundación Galileo Galilei, Rambla José Ana Fernández Pérez, 7, E-38712 Breña Baja (Spain)
5. University of British Columbia, Vancouver, BC V6T1Z1 (Canada)
6. Cape Breton University, 1250 Grand Lake Road, Sydney NS B1P 6L2 (Canada)
7. University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 (United States)
8. California Institute of Technology, Pasadena, CA 91125 (United States)
9. University of Hawai'i at Mānoa, Hilo, HI 96720 (United States)

We report the first planet discovery from the two-wheeled Kepler (K2) mission: HIP 116454 b. The host star HIP 116454 is a bright (V = 10.1, K = 8.0) K1 dwarf with high proper motion and a parallax-based distance of 55.2 ± 5.4 pc. Based on high-resolution optical spectroscopy, we find that the host star is metal-poor with [Fe/H] =–0.16 ± 0.08 and has a radius R {sub *} = 0.716 ± 0.024 R {sub ☉} and mass M {sub *} = 0.775 ± 0.027 M {sub ☉}. The star was observed by the Kepler spacecraft during its Two-Wheeled Concept Engineering Test in 2014 February. During the 9 days of observations, K2 observed a single transit event. Using a new K2 photometric analysis technique, we are able to correct small telescope drifts and recover the observed transit at high confidence, corresponding to a planetary radius of R{sub p} = 2.53 ± 0.18 R {sub ⊕}. Radial velocity observations with the HARPS-N spectrograph reveal a 11.82 ± 1.33 M {sub ⊕} planet in a 9.1 day orbit, consistent with the transit depth, duration, and ephemeris. Follow-up photometric measurements from the MOST satellite confirm the transit observed in the K2 photometry and provide a refined ephemeris, making HIP 116454 b amenable for future follow-up observations of this latest addition to the growing population of transiting super-Earths around nearby, bright stars.

• OSTI ID: 22364214
• Journal Information: Astrophysical Journal, Vol. 800, Issue 1; 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
DETECTION
DISTANCE
MASS
METALS
ORBITS
PHOTOMETRY
PLANETS
PROPER MOTION
RADIAL VELOCITY
RESOLUTION
SATELLITES
STARS
TELESCOPES