JWST-TST DREAMS: Quartz Clouds in the Atmosphere of WASP-17b

Clouds are prevalent in many of the exoplanet atmospheres that have been observed to date. For transiting exoplanets, we know if clouds are present because they mute spectral features and cause wavelength-dependent scattering. While the exact composition of these clouds is largely unknown, this information is vital to understanding the chemistry and energy budget of planetary atmospheres. In this work, we observe one transit of the hot Jupiter WASP-17b with JWST's MIRI LRS and generate a transmission spectrum from 5-12 $\rm{\mu}$m. These wavelengths allow us to probe absorption due to the vibrational modes of various predicted cloud species. Our transmission spectrum shows additional opacity centered at 8.6 $\rm{\mu}$m, and detailed atmospheric modeling and retrievals identify this feature as SiO$_2$(s) (quartz) clouds. The SiO$_2$(s) clouds model is preferred at 3.5-4.2$\sigma$ versus a cloud-free model and at 2.6$\sigma$ versus a generic aerosol prescription. We find the SiO$_2$(s) clouds are comprised of small ${\sim}0.01$ $\rm{\mu}$m particles, which extend to high altitudes in the atmosphere. The atmosphere also shows a depletion of H$_2$O, a finding consistent with the formation of high-temperature aerosols from oxygen-rich species. This work is part of a series of studies by our JWST Telescope Scientist Team (JWST-TST), in which we will use Guaranteed Time Observations to perform Deep Reconnaissance of Exoplanet Atmospheres through Multi-instrument Spectroscopy (DREAMS).Comment: 19 pages, 7 figures, accepted for publication in ApJ

Early Release Science of the exoplanet WASP-39b with JWST NIRCam

Measuring the metallicity and carbon-to-oxygen (C/O) ratio in exoplanet atmospheres is a fundamental step towards constraining the dominant chemical processes at work and, if in equilibrium, revealing planet formation histories. Transmission spectroscopy provides the necessary means by constraining the abundances of oxygen- and carbon-bearing species; however, this requires broad wavelength coverage, moderate spectral resolution, and high precision that, together, are not achievable with previous observatories. Now that JWST has commenced science operations, we are able to observe exoplanets at previously uncharted wavelengths and spectral resolutions. Here we report time-series observations of the transiting exoplanet WASP-39b using JWST's Near InfraRed Camera (NIRCam). The long-wavelength spectroscopic and short-wavelength photometric light curves span 2.0 - 4.0 $\mu$m, exhibit minimal systematics, and reveal well-defined molecular absorption features in the planet's spectrum. Specifically, we detect gaseous H$_2$O in the atmosphere and place an upper limit on the abundance of CH$_4$. The otherwise prominent CO$_2$ feature at 2.8 $\mu$m is largely masked by H$_2$O. The best-fit chemical equilibrium models favour an atmospheric metallicity of 1-100$\times$ solar (i.e., an enrichment of elements heavier than helium relative to the Sun) and a sub-stellar carbon-to-oxygen (C/O) ratio. The inferred high metallicity and low C/O ratio may indicate significant accretion of solid materials during planet formation or disequilibrium processes in the upper atmosphere.Comment: 35 pages, 13 figures, 3 tables, Nature, accepte

Transmission Spectroscopy of WASP-79b from 0.6 to 5.0 μm

As part of the Panchromatic Exoplanet Treasury 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., we examine Hubble Space Telescope (HST)/Wide Field Camera 3 (WFC3) (1.125-1.650 μm), Magellan/Low Dispersion Survey Spectrograph (LDSS)-3C (0.6-1 μm) data, and Spitzer data (3.6 and 4.5 μm). Using data from all three instruments, we constrain the water abundance to be -2.20 ≤ log(HO) ≤ -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 Transiting Exoplanet Survey Satellite (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 James Webb Space Telescope (JWST) Director's Discretionary Early Release Science (ERS) program, with ERS observations planned to be the first to execute in Cycle 1. Transiting exoplanets have been approved for 78.1 hr 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 hr in four different instrument modes, providing substantially more data by which to investigate this hot Jupiter.With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737

Transmission Spectroscopy of WASP-79b from 0.6 to 5.0 μm

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 $\leq$ log(H$_2$O) $\leq$ --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

JWST/NIRCam Transmission Spectroscopy of the Nearby Sub-Earth GJ 341b -- Supplementary Material

Supplementary material for 'JWST/NIRCam Transmission Spectroscopy of the Nearby Sub-Earth GJ 341b' by Kirk et al., AJ (2024). This repository contains six categories of data products: Data reduction reproduction — Eureka! control files (.ecf) and parameter files (.epf) alongside Tiberius input parameter files. These allow replication of our data reduction, light curve fitting, and transmission spectra extraction using the open-source code Eureka! and Tiberius. Stellar spectra — (Non flux calibrated) observed stellar spectra of GJ 341 for all three NIRCam visits as extracted with Eureka! and Tiberius. We also include flux calibrated stellar spectra for all three visits as extracted with Tiberius. Light curves — Reduced white and spectroscopic light curves from three data reduction codes (Eureka!, Tiberius, and Tswift) for all three NIRCam visits. Transmission spectra — Reduced transmission spectra from three data reduction codes (Eureka!, Tiberius, and Tswift) for all three NIRCam visits. Forward models — Set of four atmosphere forward models as presented in Kirk et al. 2024. Retrieved models — The median retrieved atmosphere model for each of the three reductions (Eureka!, Tiberius, and Tswift) as presented in Kirk et al. 2024. For any additional data requests or questions, please contact: [email protected]

Double Trouble (GJ 1132b JWST Transits NIRSpec G395H) — Supplementary Material

Supplementary material for 'Double Trouble: Two Transits of the Super-Earth GJ 1132 b Observed with JWST NIRSpec G395H' by May & MacDonald et al., ApJL (2023). This repository contains four categories of data products: Data reduction reproduction — Eureka! control files (.ecf) and parameter files (.epf) alongside saved Stage 3 output for both G395H visits. These allow replication of our data reduction, light curve fitting, and transmission spectra extraction using the open-source code Eureka! Transmission spectra — Reduced transmission spectra from three data reduction codes (Eureka!, FIREFLy, and ExoTiC-JEDI) for both G395H visits. Stellar spectra — Flux calibrated observed stellar spectra of GJ 1132 from each G395H visit. Retrievals — Corner plots and parameter statistics summaries from atmospheric and stellar contamination retrievals applied to both G395H visits (Eureka! reduction). The retrievals used the open-source code POSEIDON. For any additional data requests or questions, please contact: [email protected]

Double Trouble (GJ 1132b JWST Transits NIRSpec G395H) — Supplementary Material

Supplementary material for 'Double Trouble: Two Transits of the Super-Earth GJ 1132 b Observed with JWST NIRSpec G395H' by May & MacDonald et al., ApJL (2023). This repository contains four categories of data products: Data reduction reproduction — Eureka! control files (.ecf) and parameter files (.epf) alongside saved Stage 3 output for both G395H visits. These allow replication of our data reduction, light curve fitting, and transmission spectra extraction using the open-source code Eureka! Transmission spectra — Reduced transmission spectra from three data reduction codes (Eureka!, FIREFLy, and ExoTiC-JEDI) for both G395H visits. Stellar spectra — Flux calibrated observed stellar spectra of GJ 1132 from each G395H visit. Retrievals — Corner plots and parameter statistics summaries from atmospheric and stellar contamination retrievals applied to both G395H visits (Eureka! reduction). The retrievals used the open-source code POSEIDON. For any additional data requests or questions, please contact: [email protected]

JWST-TST DREAMS: Quartz Clouds in the Atmosphere of WASP-17b

Clouds are prevalent in many of the exoplanet atmospheres that have been observed to date. For transiting exoplanets, we know if clouds are present because they mute spectral features and cause wavelength-dependent scattering. While the exact composition of these clouds is largely unknown, this information is vital to understanding the chemistry and energy budget of planetary atmospheres. In this work, we observe one transit of the hot Jupiter WASP-17b with JWST’s Mid-Infrared Instrument Low Resolution Spectrometer and generate a transmission spectrum from 5 to 12 μ m. These wavelengths allow us to probe absorption due to the vibrational modes of various predicted cloud species. Our transmission spectrum shows additional opacity centered at 8.6 μ m, and detailed atmospheric modeling and retrievals identify this feature as SiO _2 (s) (quartz) clouds. The SiO _2 (s) clouds model is preferred at 3.5–4.2 σ versus a cloud-free model and at 2.6 σ versus a generic aerosol prescription. We find the SiO _2 (s) clouds are composed of small ∼0.01 μ m particles, which extend to high altitudes in the atmosphere. The atmosphere also shows a depletion of H _2 O, a finding consistent with the formation of high-temperature aerosols from oxygen-rich species. This work is part of a series of studies by our JWST Telescope Scientist Team (JWST-TST), in which we will use Guaranteed Time Observations to perform Deep Reconnaissance of Exoplanet Atmospheres through Multi-instrument Spectroscopy (DREAMS)

JWST-TST DREAMS: Quartz Clouds in the Atmosphere of WASP-17b

Data and models accompanying the publication "JWST-TST DREAMS: Quartz Clouds in the Atmosphere of WASP-17b". Here we include: Data, ExoTiC-MIRI reduction of JWST MIRI LRS transit observations Data, Eureka! reduction of JWST MIRI LRS transit observations Models, ATMO forward modelling. Models, PICASO+VIRGA forward modelling. Models, POSEIDON retrievals. Models, petitRADTRANS retrievals. Manuscript DOI: [DOI] and [LINK

JWST-TST DREAMS: Quartz Clouds in the Atmosphere of WASP-17b

Data and models accompanying the publication "JWST-TST DREAMS: Quartz Clouds in the Atmosphere of WASP-17b". Here we include: Data, ExoTiC-MIRI reduction of JWST MIRI LRS transit observations Data, Eureka! reduction of JWST MIRI LRS transit observations Models, ATMO forward modelling. Models, PICASO+VIRGA forward modelling. Models, POSEIDON retrievals. Models, petitRADTRANS retrievals. Manuscript DOI: [DOI] and [LINK