Native-resolution retrievals on 0.97-5.27 micron JWST spectra of VHS 1256 b find a ~79% cloud deck, solar-like metallicity and C/O, and depleted 18O in a partially cloudy disequilibrium atmosphere.
Atmospheric Chemistry in Giant Planets, Brown Dwarfs, and Low-Mass Dwarf Stars III. Iron, Magnesium, and Silicon
5 Pith papers cite this work. Polarity classification is still indexing.
abstract
We use thermochemical equilibrium calculations to model iron, magnesium, and silicon chemistry in the atmospheres of giant planets, brown dwarfs, extrasolar giant planets (EGPs), and low-mass stars. The behavior of individual Fe-, Mg-, and Si-bearing gases and condensates is determined as a function of temperature, pressure, and metallicity. Our results are thus independent of any particular model atmosphere. The condensation of Fe metal strongly affects iron chemistry by efficiently removing Fe-bearing species from the gas phase. Monatomic Fe is the most abundant Fe-bearing gas throughout the atmospheres of EGPs and L dwarfs and in the deep atmospheres of giant planets and T dwarfs. Mg- and Si-bearing gases are effectively removed from the atmosphere by forsterite (Mg2SiO4) and enstatite (MgSiO3) cloud formation. Monatomic Mg is the dominant magnesium gas throughout the atmospheres of EGPs and L dwarfs and in the deep atmospheres of giant planets and T dwarfs. Silicon monoxide (SiO) is the most abundant Si-bearing gas in the deep atmospheres of brown dwarfs and EGPs, whereas SiH4 is dominant in the deep atmosphere of Jupiter and other gas giant planets. Several other Fe-, Mg-, and Si-bearing gases become increasingly important with decreasing effective temperature. In principle, a number of Fe, Mg, and Si gases are potential tracers of weather or diagnostic of temperature in substellar atmospheres.
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astro-ph.EP 5years
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UNVERDICTED 5representative citing papers
Phase-resolved high-resolution spectroscopy of CoRoT-2b measures sub-synchronous rotation at 2.6-sigma significance, consistent with its western hotspot offset.
High-resolution M-band spectroscopy detects super-stellar SiO in TWA 5 B, implying no significant magnesium-silicate clouds and formation consistent with core accretion beyond the CO snowline or gravitational instability with solid enrichment.
Panchromatic JWST spectrum of WASP-121 b detects SiO and measures refractory-to-volatile ratios 3x stellar, consistent with mixed solid-gas accretion or migration with continued solid accretion.
Retrievals on six isolated brown dwarfs yield near-solar C/O (0.51-0.63), metallicities, and 12C/13C ratios (91-155) supporting molecular cloud fragmentation origin.
citing papers explorer
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Native-resolution retrievals of VHS 1256-1257 b spanning the JWST/NIRSpec wavelength range: Chemical composition of a partially cloudy atmosphere
Native-resolution retrievals on 0.97-5.27 micron JWST spectra of VHS 1256 b find a ~79% cloud deck, solar-like metallicity and C/O, and depleted 18O in a partially cloudy disequilibrium atmosphere.
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Unraveling the Mystery of the Peculiar and Young Hot Jupiter CoRoT-2b II: Phase Resolved Emission Spectroscopy with VLT/CRIRES+ and Gemini-S/IGRINS
Phase-resolved high-resolution spectroscopy of CoRoT-2b measures sub-synchronous rotation at 2.6-sigma significance, consistent with its western hotspot offset.
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The CRIMSON survey I: super-stellar SiO in the directly imaged companion TWA 5 B from high-resolution M-band spectroscopy
High-resolution M-band spectroscopy detects super-stellar SiO in TWA 5 B, implying no significant magnesium-silicate clouds and formation consistent with core accretion beyond the CO snowline or gravitational instability with solid enrichment.
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The panchromatic JWST dayside spectrum of WASP-121 b reveals a refractory-rich formation
Panchromatic JWST spectrum of WASP-121 b detects SiO and measures refractory-to-volatile ratios 3x stellar, consistent with mixed solid-gas accretion or migration with continued solid accretion.
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The ESO SupJup Survey XI. Atmospheric properties of six isolated M- and L-type dwarfs with CRIRES+
Retrievals on six isolated brown dwarfs yield near-solar C/O (0.51-0.63), metallicities, and 12C/13C ratios (91-155) supporting molecular cloud fragmentation origin.