Evidence for TiO in the atmosphere of the hot Jupiter HAT-P-65 b

Abstract

We present the low-resolution transmission spectra of the puffy hot Jupiter HAT-P-65b (0.53 M${}_{\mathrm{Jup}}$, 1.89 R${}_{\mathrm{Jup}}$, $T_{\mathrm{eq}}=1930$ K), based on two transits observed using the OSIRIS spectrograph on the 10.4 m Gran Telescopio CANARIAS (GTC). The transmission spectra of the two nights are consistent, covering the wavelength range 517--938 nm and consisting of mostly 5 nm spectral bins. We perform equilibrium-chemistry spectral retrieval analyses on the jointly fitted transmission spectrum and obtain an equilibrium temperature of $1645_{-244}^{+255}$ K and a cloud coverage of $36_{-17}^{+23}$%, revealing a relatively clear planetary atmosphere. Based on free-chemistry retrieval, we report strong evidence for TiO. Additional individual analyses in each night reveal weak-to-moderate evidence for TiO in both nights, but moderate evidence for Na or VO only in one of the nights. Future high-resolution Doppler spectroscopy as well as emission observations will help confirm the presence of TiO and constrain its role in shaping the vertical thermal structure of HAT-P-65b's atmosphere.

15 pages, 8 figures, accepted for publication in ApJL

References in corpus (23)

• Bayes in the sky: Bayesian inference and model selection in cosmology
• Achieving better than 1 minute accuracy in the Heliocentric and Barycentric Julian Dates
• petitRADTRANS: a Python radiative transfer package for exoplanet characterization and retrieval
• On the radiative equilibrium of irradiated planetary atmospheres
• Rayleigh scattering in the transit spectrum of HD 189733b
• Can TiO Explain Thermal Inversions in the Upper Atmospheres of Irradiated Giant Planets?
• Nightside condensation of iron in an ultra-hot giant exoplanet
• An ultrahot gas-giant exoplanet with a stratosphere
• Limb darkening and exoplanets: testing stellar model atmospheres and identifying biases in transit parameters
• Observing transiting planets with JWST -- Prime targets and their synthetic spectral observations
• Detection of titanium oxide in the atmosphere of a hot Jupiter
• High-Resolution Spectroscopic Detection of TiO and Stratosphere in the Day-side of WASP-33b
• Neutral Iron Emission Lines From The Day-side Of KELT-9b -- The GAPS Programme With HARPS-N At TNG XX
• Evidence for a Dayside Thermal Inversion and High Metallicity for the Hot Jupiter WASP-18b
• The atmosphere of HD 209458b seen with ESPRESSO. No detectable planetary absorptions at high resolution
• A temperature inversion with atomic iron in the ultra-hot dayside atmosphere of WASP-189b
• HAT-P-65b and HAT-P-66b: Two Transiting Inflated Hot Jupiters and Observational Evidence for the Re-Inflation of Close-In Giant Planets
• Detection of Fe\,{\sc i} Emission in the Day-side Spectrum of WASP-33b
• Is TiO emission present in the ultra-hot Jupiter WASP-33b? A reassessment using the improved ExoMol Toto line list
• Search for TiO and Optical Night-side Emission from the Exoplanet WASP-33b
• Detection of Na in WASP-21b's lower and upper atmosphere
• An enhanced slope in the transmission spectrum of the hot Jupiter WASP-104b
• Role of the impact parameter in exoplanet transmission spectroscopy

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• The origin of the high metallicity of close-in giant exoplanets II The nature of the sweet spot for accretion
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• Simultaneous multicolour transit photometry of hot Jupiters HAT-P-19b, HAT-P-51b, HAT-P-55b, and HAT-P-65b
• Evidence for stellar contamination and water absorption in NGTS-5b's transmission spectra with GTC/OSIRIS
• The Effect of Atmospheric Chemistry on the Optical Geometric Albedos of Hot Jupiters