English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
 
 
DownloadE-Mail
  Stellar impact on disequilibrium chemistry and observed spectra of hot Jupiter atmospheres

Shulyak, D., Lara, L. M., Rengel, M., & Nemec, N.-E. (2020). Stellar impact on disequilibrium chemistry and observed spectra of hot Jupiter atmospheres. Astronomy and Astrophysics, 639: A48. doi:10.1051/0004-6361/201937210.

Item is

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Shulyak, Denis1, Author           
Lara, L. M., Author
Rengel, Miriam1, Author           
Nemec, Nina-Elisabeth2, 3, 4, Author           
Affiliations:
1Department Planets and Comets, Max Planck Institute for Solar System Research, Max Planck Society, ou_1832288              
2Department Sun and Heliosphere, Max Planck Institute for Solar System Research, Max Planck Society, ou_1832289              
3IMPRS for Solar System Science at the University of Göttingen, Max Planck Institute for Solar System Research, Max Planck Society, Justus-von-Liebig-Weg 3, 37077 Göttingen, DE, ou_1832290              
4ERC Starting Grant: Connecting Solar and Stellar Variabilities (SOLVe), Max Planck Institute for Solar System Research, Max Planck Society, ou_3164811              

Content

show
hide
Free keywords: planets and satellites: atmospheres / planets and satellites: composition / stars: activity / methods: numerical
 Abstract: Aims. We study the effect of disequilibrium processes (photochemistry and vertical transport) on mixing ratio profiles of neutral species and on the simulated spectra of a hot Jupiter exoplanet that orbits stars of various spectral types. We additionally address the impact of stellar activity that should be present, to various degrees, in all stars with convective envelopes.

Methods. We used the VULCAN chemical kinetic code to compute number densities of species in irradiated planetary atmospheres. The temperature-pressure profile of the atmosphere was computed with the HELIOS code. We also utilized the τ-REx forward model to predict the spectra of planets in primary and secondary eclipses. In order to account for the stellar activity, we made use of the observed solar extreme ultraviolet (XUV) spectrum taken from Virtual Planetary Laboratory as a proxy for an active sun-like star.

Results. We find large changes in the mixing ratios of most chemical species in planets orbiting A-type stars, which radiate strong XUV flux thereby inducing a very effective photodissociation. For some species, these changes can propagate very deep into the planetary atmosphere to pressures of around 1 bar. To observe disequilibrium chemistry we favor hot Jupiters with temperatures Teq = 1000 K and ultra-hot Jupiters, with Teq ≈ 3000 K,which also have temperature inversion in their atmospheres. On the other hand, disequilibrium calculations predict no noticeable changes in spectra of planets with intermediate temperatures. We also show that stellar activity similar to that of the modern Sun drives important changes in mixing ratio profiles of atmospheric species. However, these changes take place at very high atmospheric altitudes and thus do not affect predicted spectra. Finally, we estimate that the effect of disequilibrium chemistry in planets orbiting nearby bright stars could be robustly detected and studied with future missions with spectroscopic capabilities in infrared such as James Webb Space Telescope and ARIEL.

Details

show
hide
Language(s): eng - English
 Dates: 2020
 Publication Status: Published online
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Type: Peer
 Identifiers: DOI: 10.1051/0004-6361/201937210
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Astronomy and Astrophysics
  Other : Astron. Astrophys.
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: Les Ulis Cedex A France : EDP Sciences
Pages: 16 Volume / Issue: 639 Sequence Number: A48 Start / End Page: - Identifier: ISSN: 1432-0746
ISSN: 0004-6361
CoNE: https://pure.mpg.de/cone/journals/resource/954922828219_1