Hot Exoplanet Atmospheres Resolved with Transit Spectroscopy (HEARTS) VII. Detection of sodium on the long-transiting inflated sub-Saturn KELT-11 b

Abstract

KELT-11b is an inflated sub-Saturn with a hot atmosphere and that orbits a bright evolved subgiant star, making it a prime choice for atmospheric characterization, but that transits its host star for more than seven hours. We observed this system in series of three consecutive nights with the HARPS spectrograph and report on the analysis of the transmission spectrum obtained from this dataset. Our results highlight the potential for independent observations of a long-transiting planet over consecutive nights. Our study reveals a sodium excess absorption of $0.28\pm 0.05$ and $0.50\pm 0.06$ in the Na D1 and D2 lines, respectively. This corresponds to 1.44 and 1.69 times the white-light planet radius in the line cores. Wind pattern modeling tends to prefer day-to-night side winds with no vertical winds, which is surprising considering the planet bloatedness. The modeling of the Rossiter-Mclaughlin effect yields a significantly misaligned orbit, with a projected spin-orbit angle of $\lambda =-77.86_{-2.26}^{+2.36}{}^{\circ }$. The characteristics of KELT-11 b, notably its extreme scale height and long transit, make it an ideal and unique target for next-generation telescopes. Our results as well as recent findings from HST, TESS, and CHEOPS observations could make KELT-11 b a benchmark exoplanet in atmospheric characterization.

arXiv comment19 pages, 18 figures, 8 tables. Accepted for publication in Astronomy & Astrophysics

References in corpus (79)

• emcee: The MCMC Hammer
• Gaia Data Release 2. Summary of the contents and survey properties
• The Gaia mission
• Detection of Planetary Transits Across a Sun-like Star
• Detection of an Extrasolar Planet Atmosphere
• Bayes in the sky: Bayesian inference and model selection in cosmology
• batman: BAsic Transit Model cAlculatioN in Python
• A continuum from clear to cloudy hot-Jupiter exoplanets without primordial water depletion
• The orbital motion, absolute mass, and high-altitude winds of exoplanet HD209458b
• Theoretical Transmission Spectra During Extrasolar Giant Planet Transits
• Molecfit: A general tool for telluric absorption correction. I. Method and application to ESO instruments
• Obliquities of Hot Jupiter host stars: Evidence for tidal interactions and primordial misalignments
• Detection of oxygen and carbon in the hydrodynamically escaping atmosphere of the extrasolar planet HD209458b
• Infrared Transmission Spectroscopy of the Exoplanets HD209458b and XO-1b Using the Wide Field Camera-3 on the Hubble Space Telescope
• A giant comet-like cloud of hydrogen escaping the warm Neptune-mass exoplanet GJ 436b
• ELODIE metallicity-biased search for transiting Hot Jupiters II. A very hot Jupiter transiting the bright K star HD189733
• Molecfit: A general tool for telluric absorption correction II. Quantitative evaluation on ESO-VLT X-Shooter spectra
• Sodium Absorption From the Exoplanetary Atmosphere of HD189733b Detected in the Optical Transmission Spectrum
• Evaporation of the planet HD189733b observed in HI Lyman-alpha
• Dearth of short-period Neptunian exoplanets - a desert in period-mass and period-radius planes
• Exoplanetary Atmospheres: Key Insights, Challenges and Prospects
• Spectrally resolved detection of sodium in the atmosphere of HD189733b with the HARPS spectrograph
• The Spectroscopic Orbit of the Planetary Companion Transiting HD209458
• The CHEOPS mission
• Ground-based detection of an extended helium atmosphere in the Saturn-mass exoplanet WASP-69b
• Ground-based detection of sodium in the transmission spectrum of exoplanet HD209458b
• Spectrally resolved helium absorption from the extended atmosphere of a warm Neptune-mass exoplanet
• Mass-Metallicity Trends in Transiting Exoplanets from Atmospheric Abundances of H${}_2$O, Na, and K
• PASTIS: Bayesian extrasolar planet validation. I. General framework, models, and performance
• Temperature-Pressure Profile of the hot Jupiter HD 189733b from HST Sodium Observations: Detection of Upper Atmospheric Heating
• Detection of titanium oxide in the atmosphere of a hot Jupiter
• Stellar obliquities in exoplanetary systems
• The Rossiter-McLaughlin effect reloaded: Probing the 3D spin-orbit geometry, differential stellar rotation, and the spatially-resolved stellar spectrum of star-planet systems
• The Complete transmission spectrum of WASP-39b with a precise water constraint
• The Oblique Orbit of the Super-Neptune HAT-P-11b
• Hot Exoplanet Atmospheres Resolved with Transit Spectroscopy (HEARTS) IV. A spectral inventory of atoms and molecules in the high-resolution transmission spectrum of WASP-121 b
• Orbital misalignment of the Neptune-mass exoplanet GJ 436b with the spin of its cool star
• Three sub-Jupiter-mass planets: WASP-69b & WASP-84b transit active K dwarfs and WASP-70Ab transits the evolved primary of a G4+K3 binary
• Atmospheric Rossiter-McLaughlin effect and transmission spectroscopy of WASP-121b with ESPRESSO
• Magnetic field strengths of hot Jupiters from signals of star-planet interactions
• High-resolution confirmation of an extended helium atmosphere around WASP-107b
• Three irradiated and bloated hot Jupiters: WASP-76b, WASP-82b & WASP-90b
• Hot Exoplanet Atmospheres Resolved with Transit Spectroscopy (HEARTS) - II. A broadened sodium feature on the ultra-hot giant WASP-76b
• WASP-39b: a highly inflated Saturn-mass planet orbiting a late G-type star
• Hot Exoplanet Atmospheres Resolved with Transit Spectroscopy (HEARTS) I. Detection of hot neutral sodium at high altitudes on WASP-49b
• The HARPS search for southern extra-solar planets. XXXVIII. Bayesian re-analysis of three systems. New super-Earths, unconfirmed signals, and magnetic cycles
• Calibration of Equilibrium Tide Theory for Extrasolar Planet Systems II
• Hot Exoplanet Atmospheres Resolved with Transit Spectroscopy (HEARTS) III. Atmospheric structure of the misaligned ultra-hot Jupiter WASP-121b
• Detection of sodium in the atmosphere of WASP-69b
• ESPRESSO high resolution transmission spectroscopy of WASP-76b
• The GTC exoplanet transit spectroscopy survey IX. Detection of Haze, Na, K, and Li in the super-Neptune WASP-127b
• Mass loss rate and local thermodynamic state of KELT-9 b thermosphere from the hydrogen Balmer series
• Detection of neutral atomic species in the ultra-hot jupiter WASP-121b
• The center-to-limb variation across the Fraunhofer lines of HD 189733; Sampling the stellar spectrum using a transiting planet
• The GAPS Programme with HARPS-N at TNG XVI: Measurement of the Rossiter-McLaughlin effect of the transiting planetary systems HAT-P-3, HAT-P-12, HAT-P-22, WASP-39 and WASP-60
• Search for water vapor in the high-resolution transmission spectrum of HD189733b in the visible
• The effect of the stellar absorption line centre-to-limb variation on exoplanet transmission spectrum observations
• From dense hot Jupiter to low-density Neptune: The discovery of WASP-127b, WASP-136b and WASP-138b
• Wind of Change: retrieving exoplanet atmospheric winds from high-resolution spectroscopy
• The atmosphere of HD 209458b seen with ESPRESSO. No detectable planetary absorptions at high resolution
• Into the Storm: Diving into the winds of the ultra hot Jupiter WASP-76 b with HARPS and ESPRESSO
• The HARPS search for southern extra-solar planets. XLIII. A compact system of four super-Earth planets orbiting HD 215152
• Is there NaI in the atmosphere of HD 209458b? Effect of the centre-to-limb variation and Rossiter-McLaughlin effect in transmission spectroscopy studies
• WASP-127b: A misaligned planet with a partly cloudy atmosphere and tenuous sodium signature seen by ESPRESSO
• Analytical determination of orbital elements using Fourier analysis. I. The radial velocity case
• LRG-BEASTS: transmission spectroscopy and retrieval analysis of the highly-inflated Saturn-mass planet WASP-39b
• KELT-11b: A Highly Inflated Sub-Saturn Exoplanet Transiting the V=8 Subgiant HD 93396
• Refined architecture of the WASP-8 system: a cautionary tale for traditional Rossiter-McLaughlin analysis
• High-resolution transmission spectroscopy of four hot inflated gas giant exoplanets
• Hot Exoplanet Atmospheres Resolved with Transit Spectroscopy (HEARTS) VI. Non-detection of sodium with HARPS on the bloated super-Neptune WASP-127b
• Hot Exoplanet Atmospheres Resolved with Transit Spectroscopy (HEARTS) V. Detection of sodium on the bloated super-Neptune WASP-166b
• KELT-11 b: Abundances of water and constraints on carbon-bearing molecules from the Hubble transmission spectrum
• An Unusual Transmission Spectrum for the Sub-Saturn KELT-11b Suggestive of a Sub-Solar Water Abundance
• Telluric correction in the near-infrared: Standard star or synthetic transmission?
• How Much Information Does the Sodium Doublet Encode? Retrieval Analysis of Non-LTE Sodium Lines at Low and High Spectral Resolutions
• Probing the atmosphere of WASP-69 b with low- and high-resolution transmission spectroscopy
• Assessing telluric correction methods for Na detections with high-resolution exoplanet transmission spectroscopy
• The Hot Neptune WASP-166 b with ESPRESSO II: Confirmation of atmospheric sodium
• Determining Empirical Stellar Masses and Radii Using Transits and Gaia Parallaxes as Illustrated by Spitzer Observations of KELT-11b

Cited by in corpus (18)

• DREAM II. The spin-orbit angle distribution of close-in exoplanets under the lens of tides
• Detection of a high-velocity sodium feature on the ultra-hot Jupiter WASP-121 b
• Ponderings on the Possible Preponderance of Perpendicular Planets
• Homogeneous search for helium in the atmosphere of 11 gas giant exoplanets with SPIRou
• An atlas of resolved spectral features in the transmission spectrum of WASP-189 b with MAROON-X
• DREAM: III.A helium survey in exoplanets on the edge of the hot Neptune desert with GIANO-B@TNG
• Evidence for Primordial Alignment: Insights from Stellar Obliquity Measurements for Compact Sub-Saturn Systems
• Combined analysis of stellar and planetary absorption lines via global forward-transit simulations
• Temperature-chemistry coupling in the evolution of gas giant atmospheres driven by stellar flares
• ATREIDES I. Embarking on a trek across the exo-Neptunian landscape with the TOI-421 system
• Hydride ion continuum hides absorption signatures in the NIRPS near-infrared transmission spectrum of the ultra-hot gas giant WASP-189b
• NIGHT: a compact, near-infrared, high-resolution spectrograph to survey helium in exoplanet systems
• NIRPS detection of delayed atmospheric escape from the warm and misaligned Saturn-mass exoplanet WASP-69b
• A Time-Resolved High-Resolution Spectroscopic Analysis of Ionized Calcium and Dynamical Processes in the Ultra-Hot Jupiter HAT-P-70 b
• Hot Exoplanet Atmospheres Resolved with Transit Spectroscopy (HEARTS) VIII. Nondetection of sodium in the atmosphere of the aligned planet KELT-10b
• The ESPRESSO transmission spectrum of HD189733b : Extracting the planetary sodium and lithium signatures amid stellar contamination
• Engulfment of a hot Jupiter as a possible origin of the rapid spin and internal spin misalignment of the planet-hosting red giant Kepler-56
• DARWEN: Data-driven Algorithm for Reduction of Wide Exoplanetary Networks