Transmission spectroscopy of WASP-52 b with JWST NIRISS: Water and helium atmospheric absorption, alongside prominent star-spot crossings

Abstract

In the era of exoplanet studies with JWST, the transiting, hot gas giant WASP-52 b provides an excellent target for atmospheric characterization through transit spectroscopy. WASP-52 b orbits an active K-type dwarf recognized for its surface heterogeneities, such as star-spots and faculae, which offers challenges to atmospheric characterization via transmission spectroscopy. Previous transit observations have detected active regions on WASP-52 through crossing events in transit light-curves and via the spectral imprint of unocculted magnetic regions on transmission spectra. Here, we present the first JWST observations of WASP-52 b. Our JWST NIRISS/SOSS transit observation, obtained through the GTO 1201 Program, detects two clear spot-crossing events that deform the 0.6-2.8 $\mu$m transit light-curves of WASP-52 b. We find that these two occulted spots combined cover about 2.4 % of the stellar surface and have temperatures about 400-500 K colder than the stellar photosphere. Our NIRISS/SOSS transmission spectrum is best-fit by an atmosphere with H${}_2$O (10.8 $\sigma$), He (7.3 $\sigma$, with evidence of an escaping tail at $\sim$ 2.9 $\sigma$), hints of K (2.5 $\sigma$), and unocculted star-spots and faculae (3.6 $\sigma$). The retrieved H${}_2$O abundance ($\log$ H${}_2$O $\approx -4\pm 1$) is consistent with a subsolar or solar atmospheric metallicity for two independent data reductions. Our results underscore the importance of simultaneously modelling planetary atmospheres and unocculted stellar heterogeneities when interpreting transmission spectra of planets orbiting active stars and demonstrate the necessity of considering different stellar contamination models that account for both cold and hot active regions.

arXiv commentSubmitted to MNRAS; 17 pages, 11 figures and 3 tables

References in corpus (77)

• MultiNest: an efficient and robust Bayesian inference tool for cosmology and particle physics
• dynesty: A Dynamic Nested Sampling Package for Estimating Bayesian Posteriors and Evidences
• A new extensive library of PHOENIX stellar atmospheres and synthetic spectra
• Efficient, uninformative sampling of limb darkening coefficients for two-parameter laws
• Theoretical Transmission Spectra During Extrasolar Giant Planet Transits
• The chemical make-up of the Sun: A 2020 vision
• ExoMol molecular line lists XXX: a complete high-accuracy line list for water
• Infrared Transmission Spectroscopy of the Exoplanets HD209458b and XO-1b Using the Wide Field Camera-3 on the Hubble Space Telescope
• Detection of atmospheric haze on an extrasolar planet: The 0.55 - 1.05 micron transmission spectrum of HD189733b with the Hubble Space Telescope
• Chemical Equilibrium Abundances in Brown Dwarf and Extrasolar Giant Planet Atmospheres
• Transmission Spectra as Diagnostics of Extrasolar Giant Planet Atmospheres
• The Transit Light Source Effect: False Spectral Features and Incorrect Densities for M-dwarf Transiting Planets
• Helium in the eroding atmosphere of an exoplanet
• Juliet: a versatile modelling tool for transiting and non-transiting exoplanetary systems
• A population study of gaseous exoplanets
• ExoMol line lists III: An improved hot rotation-vibration line list for HCN and HNC
• Early Release Science of the exoplanet WASP-39b with JWST NIRSpec PRISM
• Water Vapor in the Spectrum of the Extrasolar Planet HD 189733b: 1. the Transit
• HD 209458b in New Light: Evidence of Nitrogen Chemistry, Patchy Clouds and Sub-Solar Water
• Early Release Science of the Exoplanet WASP-39b with JWST NIRSpec G395H
• Equilibrium chemistry down to 100 K - Impact of silicates and phyllosilicates on carbon/oxygen ratio
• Photochemically-produced SO${}_2$ in the atmosphere of WASP-39b
• Hubble Space Telescope times-series photometry of the planetary transit of HD189733: no moon, no rings, starspots
• ExoMol molecular line lists XXXV: a rotation-vibration line list for hot ammonia
• Early Release Science of the exoplanet WASP-39b with JWST NIRISS
• Mass-Metallicity Trends in Transiting Exoplanets from Atmospheric Abundances of H${}_2$O, Na, and K
• Transmission spectral properties of clouds for hot Jupiter exoplanets
• ExoMol line lists -- XXXIX. Ro-vibrational molecular line list for CO${}_2$
• Exoplanetary Atmospheres - Chemistry, Formation Conditions, and Habitability
• A consistent retrieval analysis of 10 Hot Jupiters observed in transmission
• Identification of carbon dioxide in an exoplanet atmosphere
• High Tide or Riptide on the Cosmic Shoreline? A Water-Rich Atmosphere or Stellar Contamination for the Warm Super-Earth GJ~486b from JWST Observations
• Atmospheric Reconnaissance of TRAPPIST-1 b with JWST/NIRISS: Evidence for Strong Stellar Contamination in the Transmission Spectra
• How stellar activity affects the size estimates of extrasolar planets
• Retrieval of planetary and stellar properties in transmission spectroscopy with Aura
• The Stagger-grid: A grid of 3D stellar atmosphere models - IV. Limb darkening coefficients
• A broadband thermal emission spectrum of the ultra-hot Jupiter WASP-18b
• The effect of stellar limb darkening values on the accuracy of the planet radii derived from photometric transit observations
• WASP-52b, WASP-58b, WASP-59b, and WASP-60b: four new transiting close-in giant planets
• Impact of occultations of stellar active regions on transmission spectra: Can occultation of a plage mimic the signature of a blue sky?
• Transit spectroscopy with JWST: Systematics, starspots and stitching
• Transit timing variations in WASP-10b induced by stellar activity?
• The Near-Infrared Transmission Spectra of TRAPPIST-1 Planets b, c, d, e, f, and g and Stellar Contamination in Multi-Epoch Transit Spectra
• A High Internal Heat Flux and Large Core in a Warm Neptune Exoplanet
• JWST/NIRISS reveals the water-rich "steam world" atmosphere of GJ 9827 d
• Empirical limb-darkening coefficients & transit parameters of known exoplanets from TESS
• Detection of Na, K, and H$\alpha$ absorption in the atmosphere of WASP-52b using ESPRESSO
• POSEIDON: A Multidimensional Atmospheric Retrieval Code for Exoplanet Spectra
• spotrod: a semi-analytic model for transits of spotted stars
• Awesome SOSS: Transmission Spectroscopy of WASP-96b with NIRISS/SOSS
• p-winds: an open-source Python code to model planetary outflows and upper atmospheres
• Orbital alignment and starspot properties in the WASP-52 planetary system
• Near-Infrared Transmission Spectroscopy of HAT-P-18b with NIRISS: Disentangling Planetary and Stellar Features in the Era of JWST
• The GTC exoplanet transit spectroscopy survey. VII. Detection of sodium in WASP-52b's cloudy atmosphere
• Constraints on Metastable Helium in the Atmospheres of WASP-69b and WASP-52b with Ultra-Narrowband Photometry
• Water and an escaping helium tail detected in the hazy and methane-depleted atmosphere of HAT-P-18b from JWST NIRISS/SOSS
• Transmission spectroscopy of the inflated exoplanet WASP-52b, and evidence for a bright region on the stellar surface
• The Near Infrared Imager and Slitless Spectrograph for the James Webb Space Telescope -- III. Single Object Slitless Spectroscopy
• Signatures of Nitrogen Chemistry in Hot Jupiter Atmospheres
• Quartz Clouds in the Dayside Atmosphere of the Quintessential Hot Jupiter HD 189733 b
• The Influence of Stellar Contamination on the Interpretation of Near Infrared Transmission Spectra of Sub-Neptune Worlds around M-Dwarfs
• Keck/NIRSPEC studies of He I in the atmospheres of two inflated hot gas giants orbiting K dwarfs: WASP-52b and WASP-177b
• WASP-52b. The effect of starspot correction on atmospheric retrievals
• APPLESOSS: A Producer of ProfiLEs for SOSS. Application to the NIRISS SOSS Mode
• The HST PanCET Program: Hints of Na I & Evidence of a Cloudy Atmosphere for the Inflated Hot Jupiter WASP-52b
• Homogeneous search for helium in the atmosphere of 11 gas giant exoplanets with SPIRou
• Starspot occultations in infrared transit spectroscopy: the case of WASP-52b
• HST PanCET Program: A Complete Near-UV to Infrared Transmission Spectrum for the Hot Jupiter WASP-79b
• ATOCA: an algorithm to treat order contamination. Application to the NIRISS SOSS mode
• MSG: A software package for interpolating stellar spectra in pre-calculated grids
• MOPSS I: Flat Optical Spectra for the Hot Jupiters WASP-4 b and WASP-52b
• Hiding in plain sight: observing planet-starspot crossings with the James Webb Space Telescope
• Determination of Starspot Covering Fraction as a function of Stellar Age from Observational Data
• Cthulhu: An Open Source Molecular and Atomic Cross Section Computation Code for Substellar Atmospheres
• Probing Na in giant exoplanets with ESPRESSO and 3D NLTE stellar spectra
• Characterization of the visit-to-visit Stability of the GR700XD Wavelength Calibration for NIRISS/SOSS Observations
• Effects of Planetary Parameters on Disequilibrium Chemistry in Irradiated Planetary Atmospheres: From Gas Giants to Sub-Neptunes

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• Deciphering transmission spectra by exploring the solar paradigm
• Information content of JWST transmission spectroscopy of the exoplanet HAT-P-12b from the optical to the mid-infrared
• An Hα Transit of HD 189733b to Assess Stellar Activity Across the Transit Chord Close to JWST Observations
• Probing the extent of WASP-52 b's atmosphere. High-resolution observations and 3D modeling insights