TY - JOUR
T1 - High-temperature photochemistry in the atmosphere of HD 189733b
AU - Line, M. R.
AU - Liang, M. C.
AU - Yung, Y. L.
N1 - Funding Information:
This work was supported by Ministerio de Ciencia e Innovaci?n (Spanish Ministry of Science and Innovation, MICINN) (SAF2014-53819-R to Luis del Peso and Benilde Jimenez; SAF2017-88771-R to Luis del Peso and Benilde Jimenez).
Funding Information:
This work was supported by Ministerio de Ciencia e Innovación (Spanish Ministry of Science and Innovation, MICINN)
PY - 2010
Y1 - 2010
N2 - Recent infrared spectroscopy of hot exoplanets is beginning to reveal their atmospheric composition. Deep within the planetary atmosphere, the composition is controlled by thermochemical equilibrium. Photochemistry becomes important higher in the atmosphere, at levels above ∼1 bar. These two chemistries compete between 1 and 10 bars in hot-Jupiter-like atmospheres, depending on the strength of the eddy mixing and temperature. HD189733b provides an excellent laboratory in which to study the consequences of chemistry of hot atmospheres. The recent spectra of HD189733b contain signatures of CH4, CO 2, CO, and H2O. Here we identify the primary chemical pathways that govern the abundances of CH4, CO2, CO, and H2O in the cases of thermochemical equilibrium chemistry, photochemistry, and their combination. Our results suggest that the disequilibrium mechanisms can significantly enhance the abundances of these species above their thermochemical equilibrium value, so some caution must be taken when assuming that an atmosphere is in strict thermochemical equilibrium.
AB - Recent infrared spectroscopy of hot exoplanets is beginning to reveal their atmospheric composition. Deep within the planetary atmosphere, the composition is controlled by thermochemical equilibrium. Photochemistry becomes important higher in the atmosphere, at levels above ∼1 bar. These two chemistries compete between 1 and 10 bars in hot-Jupiter-like atmospheres, depending on the strength of the eddy mixing and temperature. HD189733b provides an excellent laboratory in which to study the consequences of chemistry of hot atmospheres. The recent spectra of HD189733b contain signatures of CH4, CO 2, CO, and H2O. Here we identify the primary chemical pathways that govern the abundances of CH4, CO2, CO, and H2O in the cases of thermochemical equilibrium chemistry, photochemistry, and their combination. Our results suggest that the disequilibrium mechanisms can significantly enhance the abundances of these species above their thermochemical equilibrium value, so some caution must be taken when assuming that an atmosphere is in strict thermochemical equilibrium.
KW - Atmospheric effects
KW - Methods: numerical
KW - Planetary systems
KW - Planets and satellites: atmospheres
KW - Radiative transfer
KW - Stars: individual (HD 189733b)
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U2 - 10.1088/0004-637X/717/1/496
DO - 10.1088/0004-637X/717/1/496
M3 - Article
AN - SCOPUS:77953733713
SN - 0004-637X
VL - 717
SP - 496
EP - 502
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 1
ER -