A survey of eight hot Jupiters in secondary eclipse using WIRCam at CFHT

Eder Martioli; Knicole D Colón; Daniel Angerhausen; Keivan G Stassun; Joseph E Rodriguez; George Zhou; B Scott Gaudi; Joshua Pepper; Thomas G Beatty; Ramarao Tata; David J James; Jason D Eastman; Paul Anthony Wilson; Daniel Bayliss; Daniel J Stevens

doi:10.1093/mnras/stx3009

A survey of eight hot Jupiters in secondary eclipse using WIRCam at CFHT

Mon Not R Astron Soc. 2018 Mar 1;474(3):4264-4277. doi: 10.1093/mnras/stx3009. Epub 2017 Nov 23.

Authors

Eder Martioli¹, Knicole D Colón^{2

3

4}, Daniel Angerhausen^{5

6}, Keivan G Stassun^{7

8}, Joseph E Rodriguez^{7

9}, George Zhou⁹, B Scott Gaudi¹⁰, Joshua Pepper¹¹, Thomas G Beatty^{12

13}, Ramarao Tata¹⁴, David J James¹⁵, Jason D Eastman⁹, Paul Anthony Wilson¹⁶, Daniel Bayliss¹⁷, Daniel J Stevens⁷

Affiliations

¹ Laboratório Nacional de Astrofísica (LNA/MCTI), Rua Estados Unidos 154, Itajubá, MG, Brazil.
² NASA Ames Research Center, M/S 244-30, Mo ett Field, CA 94035, USA.
³ Bay Area Environmental Research Institute, 625 2nd St. Ste 209 Petaluma, CA 94952, USA.
⁴ NASA Goddard Space Flight Center, Exoplanets and Stellar Astrophysics Laboratory (Code 667), Greenbelt, MD 20771, USA.
⁵ USRA NASA Postdoctoral Program Fellow, NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771, USA.
⁶ Center for Space and Habitability, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland.
⁷ Department of Physics and Astronomy, Vanderbilt University, 6301 Stevenson Center, Nashville, TN 37235, USA.
⁸ Department of Physics, Fisk University, Nashville, TN 37208, USA.
⁹ Harvard-Smithsonian Center for Astrophysics, 60 Garden St, Cambridge, MA 02138, USA.
¹⁰ Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210, USA.
¹¹ Department of Physics, Lehigh University, 16 Memorial Drive East, Bethlehem, PA 18015, USA.
¹² Department of Astronomy & Astrophysics, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802, USA.
¹³ Center for Exoplanets and Habitable Worlds, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802, USA.
¹⁴ Ohio University, Athens, OH 45701, USA.
¹⁵ Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195, USA.
¹⁶ CNRS, UMR 7095, Institut d'Astrophysique de Paris, 98 Boulevard Arago, F-75014 Paris, France.
¹⁷ Observatoire Astronomique de l'Université de Geève, Chemin des Maillettes 51, 1290 Sauverny, Switzerland.

Abstract

We present near infrared high-precision photometry for eight transiting hot Jupiters observed during their predicted secondary eclipses. Our observations were carried out using the staring mode of the WIRCam instrument on the Canada-France-Hawaii Telescope (CFHT). We present the observing strategies and data reduction methods which delivered time series photometry with statistical photometric precision as low as 0.11%. We performed a Bayesian analysis to model the eclipse parameters and systematics simultaneously. The measured planet-to-star flux ratios allowed us to constrain the thermal emission from the day side of these hot Jupiters, as we derived the planet brightness temperatures. Our results combined with previously observed eclipses reveal an excess in the brightness temperatures relative to the blackbody prediction for the equilibrium temperatures of the planets for a wide range of heat redistribution factors. We find a trend that this excess appears to be larger for planets with lower equilibrium temperatures. This may imply some additional sources of radiation, such as reflected light from the host star and/or thermal emission from residual internal heat from the formation of the planet.

Keywords: facility: CFHT; infrared: planetary systems; instrument: WIRCam; instrumentation: photometers; stars: planetary systems.

Grants and funding

N-999999/Intramural NASA/United States