Transmission Spectroscopy of WASP-79b from 0.6 to 5.0 $\mu$m

Abstract

As part of the PanCET program, we have conducted a spectroscopic study of WASP-79b, an inflated hot Jupiter orbiting an F-type star in Eridanus with a period of 3.66 days. Building on the original WASP and TRAPPIST photometry of Smalley et al (2012), we examine HST/WFC3 (1.125 - 1.650 $\mu$m), Magellan/LDSS-3C (0.6 - 1 $\mu$m) data, and Spitzer data (3.6 and 4.5 $\mu$m). Using data from all three instruments, we constrain the water abundance to be --2.20 $\le$ log(H${}_2$O) $\le$ --1.55. We present these results along with the results of an atmospheric retrieval analysis, which favor inclusion of FeH and H${}^{-}$ in the atmospheric model. We also provide an updated ephemeris based on the Smalley, HST/WFC3, LDSS-3C, Spitzer, and TESS transit times. With the detectable water feature and its occupation of the clear/cloudy transition region of the temperature/gravity phase space, WASP-79b is a target of interest for the approved JWST Director's Discretionary Early Release Science (DD ERS) program, with ERS observations planned to be the first to execute in Cycle 1. Transiting exoplanets have been approved for 78.1 hours of data collection, and with the delay in the JWST launch, WASP-79b is now a target for the Panchromatic Transmission program. This program will observe WASP-79b for 42 hours in 4 different instrument modes, providing substantially more data by which to investigate this hot Jupiter.

References in corpus (12)

• EXOFAST: A fast exoplanetary fitting suite in IDL
• New Grids of ATLAS9 Model Atmospheres
• Fingering convection and cloudless models for cool brown dwarf atmospheres
• HST hot-Jupiter transmission spectral survey: detection of potassium in WASP-31b along with a cloud deck and Rayleigh scattering
• HAT-P-26b: A Neptune-Mass Exoplanet with a Well Constrained Heavy Element Abundance
• The Effects of Consistent Chemical Kinetics Calculations on the Pressure-Temperature Profiles and Emission Spectra of Hot Jupiters
• ACCESS I: An Optical Transmission Spectrum of GJ 1214b Reveals a Heterogeneous Stellar Photosphere
• The Transit Light Source Effect II: The Impact of Stellar Heterogeneity on Transmission Spectra of Planets Orbiting Broadly Sun-like Stars
• An emission spectrum for WASP-121b measured across the 0.8-1.1 micron wavelength range using the Hubble Space Telescope
• WASP-78b and WASP-79b: Two highly-bloated hot Jupiter-mass exoplanets orbiting F-type stars in Eridanus
• Transmission Spectroscopy of WASP-79b from 0.6 to 5.0 $\mu$m
• Spitzer Secondary Eclipse Depths with Multiple Intrapixel Sensitivity Correction Methods: Observations of WASP-13b, WASP-15b, WASP-16b, WASP-62b, and HAT-P-22b

Cited by in corpus (4)

• ARES II: Characterising the Hot Jupiters WASP-127 b, WASP-79 b and WASP-62 b with HST
• Transmission Spectroscopy of WASP-79b from 0.6 to 5.0 $\mu$m
• The HST PanCET Program: An Optical to Infrared Transmission Spectrum of HAT-P-32Ab
• Highlights of Exoplanetary Science from Spitzer