A weak spectral signature of water vapour in the atmosphere of HD 179949 b at high spectral resolution in the L-band

Abstract

High resolution spectroscopy (R > 20,000) is currently the only known method to constrain the orbital solution and atmospheric properties of non-transiting hot Jupiters. It does so by resolving the spectral features of the planet into a forest of spectral lines and directly observing its Doppler shift while orbiting the host star. In this study, we analyse VLT/CRIRES (R = 100,000) L-band observations of the non-transiting giant planet HD 179949 b centred around 3.5 microns. We observe a weak (3.0 sigma, or S/N = 4.8) spectral signature of H2O in absorption contained within the radial velocity of the planet at superior-conjunction, with a mild dependence on the choice of line list used for the modelling. Combining this data with previous observations in the K-band, we measure a detection significance of 8.4 sigma for an atmosphere that is most consistent with a shallow lapse-rate, solar C/O ratio, and with CO and H2O being the only major sources of opacity in this wavelength range. As the two sets of data were taken three years apart, this points to the absence of strong radial-velocity anomalies due, e.g., to variability in atmospheric circulation. We measure a projected orbital velocity for the planet of KP = (145.2 +- 2.0)kms^{-1} (1 sigma) and improve the error bars on this parameter by ~70%. However, we only marginally tighten constraints on orbital inclination (66.2 +3.7 -3.1 degrees) and planet mass (0.963 +0.036 -0.031 Jupiter masses), due to the dominant uncertainties of stellar mass and semi-major axis. Follow ups of radial-velocity planets are thus crucial to fully enable their accurate characterisation via high resolution spectroscopy.

arXiv commentAccepted for publication in MNRAS; 13 pages, 10 figures

References in corpus (63)

• emcee: The MCMC Hammer
• Detection of an Extrasolar Planet Atmosphere
• A terrestrial planet candidate in a temperate orbit around Proxima Centauri
• The effects of snowlines on C/O in planetary atmospheres
• A continuum from clear to cloudy hot-Jupiter exoplanets without primordial water depletion
• Catalog of Nearby Exoplanets
• The orbital motion, absolute mass, and high-altitude winds of exoplanet HD209458b
• ExoMol molecular line lists XXX: a complete high-accuracy line list for water
• Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 parsecs: The Southern Sample
• C/O ratio as a Dimension for Characterizing Exoplanetary Atmospheres
• The signature of orbital motion from the dayside of the planet tau Bootis b
• The fast spin-rotation of a young extrasolar planet
• Detection of water absorption in the day side atmosphere of HD 189733 b using ground-based high-resolution spectroscopy at 3.2 microns
• Structure and Evolution of Nearby Stars with Planets II. Physical Properties of ~1000 Cool Stars from the SPOCS Catalog
• High C/O Ratio and Weak Thermal Inversion in the Very Hot Atmosphere of Exoplanet WASP-12b
• Spectrally resolved detection of sodium in the atmosphere of HD189733b with the HARPS spectrograph
• An atmospheric radiation model for Cerro Paranal. I. The optical spectral range
• Chemical consequences of the C/O ratio on hot Jupiters: Examples from WASP-12b,CoRoT-2b, XO-1b, and HD 189733b
• Ground-based detection of an extended helium atmosphere in the Saturn-mass exoplanet WASP-69b
• Retrieving Temperatures and Abundances of Exoplanet Atmospheres with High-Resolution Cross-Correlation Spectroscopy
• Atomic iron and titanium in the atmosphere of the exoplanet KELT-9b
• Rotation and winds of exoplanet HD 189733 b measured with high-dispersion transmission spectroscopy
• 55 Cancri (Copernicus): A Multi-Planet System with a Hot Super-Earth and a Jupiter Analogue
• Spectrally resolved helium absorption from the extended atmosphere of a warm Neptune-mass exoplanet
• Model atmospheres of irradiated exoplanets: The influence of stellar parameters, metallicity, and the C/O ratio
• A spectral survey of an ultra-hot Jupiter: Detection of metals in the transmission spectrum of KELT-9 b
• Detection of carbon monoxide in the high-resolution day-side spectrum of the exoplanet HD 189733b
• A Systematic Retrieval Analysis of Secondary Eclipse Spectra II: A Uniform Analysis of Eight Planets and Their C to O Ratios
• Formation and Evolution of Planetary Systems (FEPS): Properties of Debris Dust around Solar-type Stars
• Carbon monoxide and water vapor in the atmosphere of the non-transiting exoplanet HD 179949 b
• Spatially resolved eastward winds and rotation of HD 189733b
• Extrasolar Giant Planets under Strong Stellar Irradiation
• Carbon-rich Giant Planets: Atmospheric Chemistry, Thermal Inversions, Spectra, and Formation conditions
• High-Resolution Spectroscopic Detection of TiO and Stratosphere in the Day-side of WASP-33b
• Cross-Correlation and Maximum Likelihood Analysis: A New Approach to Combine Cross-Correlation Functions
• Weighing The Non-Transiting Hot Jupiter Tau BOO b
• Detection of He I $\lambda 10830$ Å absorption on HD 189733 b with CARMENES high-resolution transmission spectroscopy
• Hot Nights on Extrasolar Planets: Mid-IR Phase Variations of Hot Jupiters
• Detection of molecular absorption in the dayside of exoplanet 51 Pegasi b?
• First Results from the Anglo-Australian Planet Search - A Brown Dwarf Candidate and a 51 Peg-like Planet
• Discovery of water at high spectral resolution in the atmosphere of 51 Peg b
• GENESIS: New Self-Consistent Models of Exoplanetary Spectra
• SPIRou: the near-infrared spectropolarimeter/high-precision velocimeter for the Canada-France-Hawaii telescope
• Near-IR Direct Detection of Water Vapor in Tau Boo b
• A search for TiO in the optical high-resolution transmission spectrum of HD 209458b: Hindrance due to inaccuracies in the line database
• Exoplanet atmospheres with GIANO. I. Water in the transmission spectrum of HD 189733b
• The High-Resolution Transmission Spectrum of HD 189733b Interpreted with Atmospheric Doppler Shifts from Three-Dimensional General Circulation Models
• He I $\lambda$ 10830 Å in the transmission spectrum of HD 209458 b
• Atmospheric dynamics and the variable transit of KELT-9 b
• On the robustness of analysis techniques for molecular detections using high resolution exoplanet spectroscopy
• The slow spin of the young sub-stellar companion GQ Lupi b and its orbital configuration
• Long-Period Objects in the Extrasolar Planetary Systems 47 UMa and 14 Her
• Exoplanet atmospheres with GIANO II. Detection of molecular absorption in the dayside spectrum of HD 102195b
• Evidence for multiple molecular species in the hot Jupiter HD 209458b
• Evidence against a strong thermal inversion in HD 209458 b from high-dispersion spectroscopy
• Multiple water band detections in the CARMENES near-infrared transmission spectrum of HD 189733 b
• Water vapor detection in the transmission spectra of HD 209458 b with the CARMENES NIR channel
• Identifying new opportunities for exoplanet characterisation at high spectral resolution
• Evidence for the Direct Detection of the Thermal Spectrum of the Non-Transiting Hot Gas Giant HD 88133 b
• Constraining Hot Jupiter Atmospheric Structure and Dynamics through Doppler Shifted Emission Spectra
• Exoplanet Atmospheres at High Spectral Resolution
• Detection of Water Vapor in the Thermal Spectrum of the Non-Transiting Hot Jupiter upsilon Andromedae b
• The carbon-to-oxygen ratio: implications for the spectra of hydrogen-dominated exoplanet atmospheres

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• Five carbon- and nitrogen-bearing species in a hot giant planet's atmosphere
• The ExoMolOP Database: Cross-sections and k-tables for Molecules of Interest in High-Temperature Exoplanet Atmospheres
• Aerosols in Exoplanet Atmospheres
• Where is the Water? Jupiter-like C/H ratio but strong H${}_2$O depletion found on $\tau$ Boötis b using SPIRou
• First Detection of Hydroxyl Radical Emission from an Exoplanet Atmosphere: High-dispersion Characterization of WASP-33b using Subaru/IRD
• Seeing above the Clouds with High Resolution Spectroscopy
• CO or no CO? Narrowing the CO abundance constraint and recovering the H2O detection in the atmosphere of WASP-127 b using SPIRou
• Black Mirror: The impact of rotational broadening on the search for reflected light from 51 Pegasi b with high resolution spectroscopy
• Characterizing exoplanetary atmospheres at high resolution with SPIRou: Detection of water on HD 189733 b
• A Near-Infrared Chemical Inventory of the Atmosphere of 55 Cancri e
• Applications of a Gaussian Process Framework for Modelling of High-Resolution Exoplanet Spectra
• The hot Neptune WASP-166 b with ESPRESSO III: A blue-shifted tentative water signal constrains the presence of clouds
• Water observed in the atmosphere of τ Bootis Ab with CARMENES/CAHA
• SPORK That Spectrum: Increasing Detection Significances from High-Resolution Exoplanet Spectroscopy with Novel Smoothing Algorithms
• New perspectives on MASCARA-1b: A combined analysis of pre- and post-eclipse emission data using CRIRES+
• A First Look at CRIRES+: Performance Assessment and Exoplanet Spectroscopy