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

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 precisionas 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.

17 pages, 19 figures, accepted for publication in the Monthly Notices of the Royal Astronomical Society

References in corpus (7)

• Possible thermochemical disequilibrium in the atmosphere of the exoplanet GJ 436b
• The Broadband Infrared Emission Spectrum of the Exoplanet HD 189733b
• Balancing the Energy Budget of Short-Period Giant Planets: Evidence for Reflective Clouds and Optical Absorbers
• KELT-2Ab: A Hot Jupiter Transiting the Bright (V=8.77) Primary Star of a Binary System
• Ks band secondary eclipses of WASP-19b and WASP-43b with the Anglo-Australian Telescope
• The Fortuitous Latitude of the Pierre Auger Observatory and Telescope Array for Reconstructing the Quadrupole Moment
• Subaru Spectroscopy and Spectral Modeling of Cygnus A

Cited by in corpus (6)

• ARES III: Unveiling the Two Faces of KELT-7 b with HST WFC3
• The secondary transit of the hot Jupiter WASP-121b at 2 $\mu$m
• Estimating dayside effective temperatures of hot Jupiters and associated uncertainties through Gaussian process regression
• Colour-colour and colour-magnitude diagrams for Hot Jupiters
• Near infrared and optical emission of WASP-5 b
• Scientific Validation of the SPARC4 Pipeline: Multi-band Imaging, Polarimetry, and Photometric Time Series for Improved Characterization of Transiting Exoplanets