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Title: Advection of Potential Temperature in the Atmosphere of Irradiated Exoplanets: A Robust Mechanism to Explain Radius Inflation

Abstract

The anomalously large radii of strongly irradiated exoplanets have remained a major puzzle in astronomy. Based on a two-dimensional steady-state atmospheric circulation model, the validity of which is assessed by comparison to three-dimensional calculations, we reveal a new mechanism, namely the advection of the potential temperature due to mass and longitudinal momentum conservation, a process occurring in the Earth’s atmosphere or oceans. In the deep atmosphere, the vanishing heating flux forces the atmospheric structure to converge to a hotter adiabat than the one obtained with 1D calculations, implying a larger radius for the planet. Not only do the calculations reproduce the observed radius of HD 209458b, but also reproduce the observed correlation between radius inflation and irradiation for transiting planets. Vertical advection of potential temperature induced by non-uniform atmospheric heating thus provides a robust mechanism to explain the inflated radii of irradiated hot Jupiters.

Authors:
 [1]; ; ; ; ; ;  [2];  [3];  [4]
  1. Maison de la Simulation, CEA-CNRS-INRIA-UPS-UVSQ, USR 3441, CEA Paris-Saclay, F-91191 Gif-Sur-Yvette (France)
  2. Astrophysics Group, University of Exeter, EX4 4QL Exeter (United Kingdom)
  3. Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY 10025 (United States)
  4. Laboratoire AIM, CEA/DSM-CNRS-Université Paris 7, Irfu/Service d’Astrophysique, CEA Paris-Saclay, F-91191 Gif-sur-Yvette (France)
Publication Date:
OSTI Identifier:
22663585
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 841; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ADVECTION; ASTRONOMY; ATMOSPHERES; COMPARATIVE EVALUATIONS; COSMOLOGICAL INFLATION; HEATING; IRRADIATION; JUPITER PLANET; LONGITUDINAL MOMENTUM; SATELLITES; STEADY-STATE CONDITIONS; THREE-DIMENSIONAL CALCULATIONS; TWO-DIMENSIONAL CALCULATIONS

Citation Formats

Tremblin, P., Chabrier, G., Mayne, N. J., Baraffe, I., Debras, F., Drummond, B., Manners, J., Amundsen, D. S., and Fromang, S., E-mail: pascal.tremblin@cea.fr. Advection of Potential Temperature in the Atmosphere of Irradiated Exoplanets: A Robust Mechanism to Explain Radius Inflation. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA6E57.
Tremblin, P., Chabrier, G., Mayne, N. J., Baraffe, I., Debras, F., Drummond, B., Manners, J., Amundsen, D. S., & Fromang, S., E-mail: pascal.tremblin@cea.fr. Advection of Potential Temperature in the Atmosphere of Irradiated Exoplanets: A Robust Mechanism to Explain Radius Inflation. United States. doi:10.3847/1538-4357/AA6E57.
Tremblin, P., Chabrier, G., Mayne, N. J., Baraffe, I., Debras, F., Drummond, B., Manners, J., Amundsen, D. S., and Fromang, S., E-mail: pascal.tremblin@cea.fr. Sat . "Advection of Potential Temperature in the Atmosphere of Irradiated Exoplanets: A Robust Mechanism to Explain Radius Inflation". United States. doi:10.3847/1538-4357/AA6E57.
@article{osti_22663585,
title = {Advection of Potential Temperature in the Atmosphere of Irradiated Exoplanets: A Robust Mechanism to Explain Radius Inflation},
author = {Tremblin, P. and Chabrier, G. and Mayne, N. J. and Baraffe, I. and Debras, F. and Drummond, B. and Manners, J. and Amundsen, D. S. and Fromang, S., E-mail: pascal.tremblin@cea.fr},
abstractNote = {The anomalously large radii of strongly irradiated exoplanets have remained a major puzzle in astronomy. Based on a two-dimensional steady-state atmospheric circulation model, the validity of which is assessed by comparison to three-dimensional calculations, we reveal a new mechanism, namely the advection of the potential temperature due to mass and longitudinal momentum conservation, a process occurring in the Earth’s atmosphere or oceans. In the deep atmosphere, the vanishing heating flux forces the atmospheric structure to converge to a hotter adiabat than the one obtained with 1D calculations, implying a larger radius for the planet. Not only do the calculations reproduce the observed radius of HD 209458b, but also reproduce the observed correlation between radius inflation and irradiation for transiting planets. Vertical advection of potential temperature induced by non-uniform atmospheric heating thus provides a robust mechanism to explain the inflated radii of irradiated hot Jupiters.},
doi = {10.3847/1538-4357/AA6E57},
journal = {Astrophysical Journal},
number = 1,
volume = 841,
place = {United States},
year = {Sat May 20 00:00:00 EDT 2017},
month = {Sat May 20 00:00:00 EDT 2017}
}
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