Phase curve and variability analysis of WASP-12b using TESS photometry

Abstract

We analyse Sector 20 TESS photometry of the ultra-hot Jupiter WASP-12b, and extract its phase curve to study the planet's atmospheric properties. We successfully recover the phase curve with an amplitude of 549 $\pm$ 62 ppm, and a secondary eclipse depth of 609${}_{-73}^{+74}$ ppm. The peak of the phase curve is shifted by 0.049 $\pm$ 0.015 in phase, implying that the brightest spot in the atmosphere is shifted from the substellar point towards the planet's evening terminator. Assuming zero albedo, the eclipse depth infers a day-side brightness temperature of 3128${}_{-68}^{+64}$ K. No significant detection of flux from the night-side is found at 60 $\pm$ 97 ppm, implying a night-side brightness temperature of $<$2529 K (1-$\sigma$). We do not detect any significant variability in the light from the planet over the $\sim$27 days of the TESS observations. Finally, we note that an ephemeris model taking orbital decay into account provides a significantly better fit than a constant-period model.

arXiv comment11 pages, 5 figures. Accepted for publication in MNRAS Letters

References in corpus (41)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• Array Programming with NumPy
• emcee: The MCMC Hammer
• The Astropy Project: Building an inclusive, open-science project and status of the v2.0 core package
• Analytic Lightcurves for Planetary Transit Searches
• New evolutionary models for pre-main sequence and main sequence low-mass stars down to the hydrogen-burning limit
• batman: BAsic Transit Model cAlculatioN in Python
• Efficient, uninformative sampling of limb darkening coefficients for two-parameter laws
• A map of the day-night contrast of the extrasolar planet HD 189733b
• Equatorial superrotation on tidally locked exoplanets
• WASP-12b: The hottest transiting planet yet discovered
• Limb and gravity-darkening coefficients for the TESS satellite at several metallicities, surface gravities, and microturbulent velocities
• Periodic Flux Variability of Stars due to the Reflex Doppler Effect Induced by Planetary Companions
• Thermal Phase Variations of WASP-12b: Defying Predictions
• Changing Phases of Alien Worlds: Probing Atmospheres of Kepler Planets with High-Precision Photometry
• Optical Phase Curves of Kepler Exoplanets
• The Orbit of WASP-12b is Decaying
• The changing phases of extrasolar planet CoRoT-1b
• The 4.5 $\mu$m full-orbit phase curve of the hot Jupiter HD 209458b
• The Effects of Irradiation on Hot Jovian Atmospheres: Heat Redistribution and Energy Dissipation
• On the Orbit of Exoplanet WASP-12b
• Li abundances in F stars: planets, rotation and galactic evolution
• Re-Evaluating WASP-12b: Strong Emission at 2.315 micron, Deeper Occultations, and an Isothermal Atmosphere
• Atmospheric Circulation of Hot Jupiters: Dayside-Nightside Temperature Differences. II. Comparison with Observations
• Variability in the Atmosphere of the Hot Giant Planet HAT-P-7 b
• Deciphering the Atmospheric Composition of WASP-12b: A Comprehensive Analysis of its Dayside Emission
• Phase curves of WASP-33b and HD 149026b and a New Correlation Between Phase Curve Offset and Irradiation Temperature
• Near-infrared Thermal Emission from WASP-12b: detections of the secondary eclipse in Ks, H & J
• Kepler observations of the beaming binary KPD 1946+4340
• Transit Timing Variation Measurements of WASP-12b and Qatar-1b: No Evidence for Additional Planets
• Thermal Emission from Transiting Very-Hot Jupiters: Prospects for Ground-based Detection at Optical Wavelengths
• Day-side z'-band emission and eccentricity of Wasp-12b
• Decaying Orbit of the Hot Jupiter WASP-12b: Confirmation with TESS Observations
• Mass Loss from the Exoplanet WASP-12b Inferred from $\text{Spitzer}$ Phase Curves
• Systematic Phase Curve Study of Known Transiting Systems from Year 1 of the TESS Mission
• Ground-based detections of thermal emission from CoRoT-1b and WASP-12b
• The Very Low Albedo of WASP-12b From Spectral Eclipse Observations with $\text{Hubble}$
• Ground-based K-band detection of thermal emission from the exoplanet TrES-3b
• ULTRACAM z'-band Detection of the Secondary Eclipse of WASP-12b
• First Light of Engineered Diffusers at the Nordic Optical Telescope Reveal Time Variability in the Optical Eclipse Depth of WASP-12b
• Storms or Systematics? The changing secondary eclipse depth of WASP-12b

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