Metallicity and Spectral Evolution of WASP 39b: The Limited Role of Hydrodynamic Escape
The recent observations on WASP-39 b by JWST have revealed hints of high metallicity within the atmosphere compared to its host star. There are various theories on how these high metallic atmospheres emerge. In this study, we closely investigate the impact of extreme escape in the form of hydrodynam...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2023-01-01
|
| Series: | The Astrophysical Journal Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.3847/2041-8213/acfaec |
| _version_ | 1827795844428988416 |
|---|---|
| author | Amy J. Louca Yamila Miguel Daria Kubyshkina |
| author_facet | Amy J. Louca Yamila Miguel Daria Kubyshkina |
| author_sort | Amy J. Louca |
| collection | DOAJ |
| description | The recent observations on WASP-39 b by JWST have revealed hints of high metallicity within the atmosphere compared to its host star. There are various theories on how these high metallic atmospheres emerge. In this study, we closely investigate the impact of extreme escape in the form of hydrodynamic escape to see its impact on atmospheric metallicity and spectral features such as CH _4 , CO _2 and SO _2 . We perform a grid simulation, with an adapted version of MESA that includes hydrodynamic escape to fully evolve planets with similar masses and radii to the currently observed WASP-39 b estimates. By making use of (photo)chemical kinetics and radiative transfer codes, we evaluate the transmission spectra at various time intervals throughout the simulation. Our results indicate that the massive size of WASP-39 b limits the metal enhancement to a maximum of ∼1.23× the initial metallicity. When incorporating metal drag, this enhancement factor is repressed to an even greater degree, resulting in an enrichment of at most ∼0.4%. As a consequence, when assuming an initial solar metallicity, metal-enriched spectral features like SO _2 are still missing after ∼9 Gyr into the simulation. This paper, thus, demonstrates that hydrodynamic escape cannot be the primary process behind the high metallicity observed in the atmosphere of WASP-39 b, suggesting instead that a metal-enhanced atmosphere was established during its formation. |
| first_indexed | 2024-03-11T18:56:12Z |
| format | Article |
| id | doaj.art-187e683f949049e7910117b8b7a72f34 |
| institution | Directory Open Access Journal |
| issn | 2041-8205 |
| language | English |
| last_indexed | 2024-03-11T18:56:12Z |
| publishDate | 2023-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal Letters |
| spelling | doaj.art-187e683f949049e7910117b8b7a72f342023-10-10T20:20:42ZengIOP PublishingThe Astrophysical Journal Letters2041-82052023-01-019561L1910.3847/2041-8213/acfaecMetallicity and Spectral Evolution of WASP 39b: The Limited Role of Hydrodynamic EscapeAmy J. Louca0https://orcid.org/0000-0002-3191-2200Yamila Miguel1https://orcid.org/0000-0002-0747-8862Daria Kubyshkina2https://orcid.org/0000-0001-9137-9818Leiden Observatory, Leiden University P.O. Box 9513, 2300 RA Leiden, The Netherlands ; louca@strw.leidenuniv.nlLeiden Observatory, Leiden University P.O. Box 9513, 2300 RA Leiden, The Netherlands ; louca@strw.leidenuniv.nl; SRON Netherlands Institute for Space Research , Niels Bohrweg 4, 2333 CA Leiden, The NetherlandsSpace Research Institute, Austrian Academy of Sciences , Schmiedlstrasse 6, A-8042 Graz, AustriaThe recent observations on WASP-39 b by JWST have revealed hints of high metallicity within the atmosphere compared to its host star. There are various theories on how these high metallic atmospheres emerge. In this study, we closely investigate the impact of extreme escape in the form of hydrodynamic escape to see its impact on atmospheric metallicity and spectral features such as CH _4 , CO _2 and SO _2 . We perform a grid simulation, with an adapted version of MESA that includes hydrodynamic escape to fully evolve planets with similar masses and radii to the currently observed WASP-39 b estimates. By making use of (photo)chemical kinetics and radiative transfer codes, we evaluate the transmission spectra at various time intervals throughout the simulation. Our results indicate that the massive size of WASP-39 b limits the metal enhancement to a maximum of ∼1.23× the initial metallicity. When incorporating metal drag, this enhancement factor is repressed to an even greater degree, resulting in an enrichment of at most ∼0.4%. As a consequence, when assuming an initial solar metallicity, metal-enriched spectral features like SO _2 are still missing after ∼9 Gyr into the simulation. This paper, thus, demonstrates that hydrodynamic escape cannot be the primary process behind the high metallicity observed in the atmosphere of WASP-39 b, suggesting instead that a metal-enhanced atmosphere was established during its formation.https://doi.org/10.3847/2041-8213/acfaecExoplanetsExoplanet astronomyTrojan planetsExtrasolar gaseous planets |
| spellingShingle | Amy J. Louca Yamila Miguel Daria Kubyshkina Metallicity and Spectral Evolution of WASP 39b: The Limited Role of Hydrodynamic Escape The Astrophysical Journal Letters Exoplanets Exoplanet astronomy Trojan planets Extrasolar gaseous planets |
| title | Metallicity and Spectral Evolution of WASP 39b: The Limited Role of Hydrodynamic Escape |
| title_full | Metallicity and Spectral Evolution of WASP 39b: The Limited Role of Hydrodynamic Escape |
| title_fullStr | Metallicity and Spectral Evolution of WASP 39b: The Limited Role of Hydrodynamic Escape |
| title_full_unstemmed | Metallicity and Spectral Evolution of WASP 39b: The Limited Role of Hydrodynamic Escape |
| title_short | Metallicity and Spectral Evolution of WASP 39b: The Limited Role of Hydrodynamic Escape |
| title_sort | metallicity and spectral evolution of wasp 39b the limited role of hydrodynamic escape |
| topic | Exoplanets Exoplanet astronomy Trojan planets Extrasolar gaseous planets |
| url | https://doi.org/10.3847/2041-8213/acfaec |
| work_keys_str_mv | AT amyjlouca metallicityandspectralevolutionofwasp39bthelimitedroleofhydrodynamicescape AT yamilamiguel metallicityandspectralevolutionofwasp39bthelimitedroleofhydrodynamicescape AT dariakubyshkina metallicityandspectralevolutionofwasp39bthelimitedroleofhydrodynamicescape |