A comparison of simulated JWST observations derived from equilibrium and non-equilibrium chemistry models of giant exoplanets

We aim to see if the difference between equilibrium and disequilibrium chemistry is observable in the atmospheres of transiting planets by the James Webb Space Telescope (JWST). We perform a case study comparing the dayside emission spectra of three planets like HD 189733b, WASP-80b, and GJ 436b, in...

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Main Authors: Blumenthal, S, Mandell, A, Hébrard, E, Batalha, N, Cubillos, P, Rugheimer, S, Wakeford, H
Format: Journal article
Published: Institute of Physics 2018
_version_ 1797081941672984576
author Blumenthal, S
Mandell, A
Hébrard, E
Batalha, N
Cubillos, P
Rugheimer, S
Wakeford, H
author_facet Blumenthal, S
Mandell, A
Hébrard, E
Batalha, N
Cubillos, P
Rugheimer, S
Wakeford, H
author_sort Blumenthal, S
collection OXFORD
description We aim to see if the difference between equilibrium and disequilibrium chemistry is observable in the atmospheres of transiting planets by the James Webb Space Telescope (JWST). We perform a case study comparing the dayside emission spectra of three planets like HD 189733b, WASP-80b, and GJ 436b, in and out of chemical equilibrium at two metallicities each. These three planets were chosen because they span a large range of planetary masses and equilibrium temperatures, from hot and Jupiter-sized to warm and Neptune-sized. We link the one-dimensional disequilibrium chemistry model from Venot et al. (2012), in which thermochemical kinetics, vertical transport, and photochemistry are taken into account, to the one-dimensional, pseudo line-by-line radiative transfer model, Pyrat bay, developed especially for hot Jupiters, and then simulate JWST spectra using PandExo for comparing the effects of temperature, metallicity, and radius. We find the most significant differences from 4 to 5 μm due to disequilibrium from CO and CO2 abundances, and also H2O for select cases. Our case study shows a certain “sweet spot” of planetary mass, temperature, and metallicity where the difference between equilibrium and disequilibrium is observable. For a planet similar to WASP-80b, JWST’s NIRSpec G395M can detect differences due to disequilibrium chemistry with one eclipse event. For a planet similar to GJ 436b, the observability of differences due to disequilibrium chemistry is possible at low metallicity given five eclipse events, but not possible at the higher metallicity.
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spelling oxford-uuid:905b9ed1-ff11-4e1b-8069-a6eb2d8c8cef2022-03-26T23:11:09ZA comparison of simulated JWST observations derived from equilibrium and non-equilibrium chemistry models of giant exoplanetsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:905b9ed1-ff11-4e1b-8069-a6eb2d8c8cefSymplectic Elements at OxfordInstitute of Physics2018Blumenthal, SMandell, AHébrard, EBatalha, NCubillos, PRugheimer, SWakeford, HWe aim to see if the difference between equilibrium and disequilibrium chemistry is observable in the atmospheres of transiting planets by the James Webb Space Telescope (JWST). We perform a case study comparing the dayside emission spectra of three planets like HD 189733b, WASP-80b, and GJ 436b, in and out of chemical equilibrium at two metallicities each. These three planets were chosen because they span a large range of planetary masses and equilibrium temperatures, from hot and Jupiter-sized to warm and Neptune-sized. We link the one-dimensional disequilibrium chemistry model from Venot et al. (2012), in which thermochemical kinetics, vertical transport, and photochemistry are taken into account, to the one-dimensional, pseudo line-by-line radiative transfer model, Pyrat bay, developed especially for hot Jupiters, and then simulate JWST spectra using PandExo for comparing the effects of temperature, metallicity, and radius. We find the most significant differences from 4 to 5 μm due to disequilibrium from CO and CO2 abundances, and also H2O for select cases. Our case study shows a certain “sweet spot” of planetary mass, temperature, and metallicity where the difference between equilibrium and disequilibrium is observable. For a planet similar to WASP-80b, JWST’s NIRSpec G395M can detect differences due to disequilibrium chemistry with one eclipse event. For a planet similar to GJ 436b, the observability of differences due to disequilibrium chemistry is possible at low metallicity given five eclipse events, but not possible at the higher metallicity.
spellingShingle Blumenthal, S
Mandell, A
Hébrard, E
Batalha, N
Cubillos, P
Rugheimer, S
Wakeford, H
A comparison of simulated JWST observations derived from equilibrium and non-equilibrium chemistry models of giant exoplanets
title A comparison of simulated JWST observations derived from equilibrium and non-equilibrium chemistry models of giant exoplanets
title_full A comparison of simulated JWST observations derived from equilibrium and non-equilibrium chemistry models of giant exoplanets
title_fullStr A comparison of simulated JWST observations derived from equilibrium and non-equilibrium chemistry models of giant exoplanets
title_full_unstemmed A comparison of simulated JWST observations derived from equilibrium and non-equilibrium chemistry models of giant exoplanets
title_short A comparison of simulated JWST observations derived from equilibrium and non-equilibrium chemistry models of giant exoplanets
title_sort comparison of simulated jwst observations derived from equilibrium and non equilibrium chemistry models of giant exoplanets
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