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Title: The atmospheric circulation and observable properties of non-synchronously rotating hot Jupiters

Abstract

We study the feasibility of observationally constraining the rotation rate of hot Jupiters, planets that are typically assumed to have been tidally locked into synchronous rotation. We use a three-dimensional General Circulation Model to solve for the atmospheric structure of two hot Jupiters (HD 189733b and HD 209458b), assuming rotation periods that are 0.5, 1, or 2 times their orbital periods (2.2 and 3.3 days, respectively), including the effect of variable stellar heating. We compare two observable properties: (1) the spatial variation of flux emitted by the planet, measurable in orbital phase curves, and (2) the net Doppler shift in transmission spectra of the atmosphere, which is tantalizingly close to being measurable in high-resolution transit spectra. Although we find little difference between the observable properties of the synchronous and non-synchronous models of HD 189733b, we see significant differences when we compare the models of HD 209458b. In particular, the slowly rotating model of HD 209458b has an atmospheric circulation pattern characterized by westward flow and an orbital phase curve that peaks after secondary eclipse (in contrast to all of our other models), while the quickly rotating model has a net Doppler shift that is more strongly blueshifted than the othermore » models. Our results demonstrate that the combined use of these two techniques may be a fruitful way to constrain the rotation rate of some planets and motivate future work on this topic.« less

Authors:
 [1];  [2]
  1. Department of Astrophysical Sciences, Princeton University, 4 Ivy Lane, Peyton Hall, Princeton, NJ 08544 (United States)
  2. Department of Physics, Grinnell College, Noyce Science Building, Grinnell, IA 50112 (United States)
Publication Date:
OSTI Identifier:
22364274
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 790; 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; ATMOSPHERIC CIRCULATION; COMPARATIVE EVALUATIONS; DOPPLER EFFECT; ECLIPSE; EMISSION; HEATING; HYDRODYNAMICS; JUPITER PLANET; RADIANT HEAT TRANSFER; RESOLUTION; ROTATION; SATELLITE ATMOSPHERES; SATELLITES; SPECTRA; THREE-DIMENSIONAL CALCULATIONS; TRANSMISSION

Citation Formats

Rauscher, Emily, and Kempton, Eliza M. R. The atmospheric circulation and observable properties of non-synchronously rotating hot Jupiters. United States: N. p., 2014. Web. doi:10.1088/0004-637X/790/1/79.
Rauscher, Emily, & Kempton, Eliza M. R. The atmospheric circulation and observable properties of non-synchronously rotating hot Jupiters. United States. doi:10.1088/0004-637X/790/1/79.
Rauscher, Emily, and Kempton, Eliza M. R. Sun . "The atmospheric circulation and observable properties of non-synchronously rotating hot Jupiters". United States. doi:10.1088/0004-637X/790/1/79.
@article{osti_22364274,
title = {The atmospheric circulation and observable properties of non-synchronously rotating hot Jupiters},
author = {Rauscher, Emily and Kempton, Eliza M. R.},
abstractNote = {We study the feasibility of observationally constraining the rotation rate of hot Jupiters, planets that are typically assumed to have been tidally locked into synchronous rotation. We use a three-dimensional General Circulation Model to solve for the atmospheric structure of two hot Jupiters (HD 189733b and HD 209458b), assuming rotation periods that are 0.5, 1, or 2 times their orbital periods (2.2 and 3.3 days, respectively), including the effect of variable stellar heating. We compare two observable properties: (1) the spatial variation of flux emitted by the planet, measurable in orbital phase curves, and (2) the net Doppler shift in transmission spectra of the atmosphere, which is tantalizingly close to being measurable in high-resolution transit spectra. Although we find little difference between the observable properties of the synchronous and non-synchronous models of HD 189733b, we see significant differences when we compare the models of HD 209458b. In particular, the slowly rotating model of HD 209458b has an atmospheric circulation pattern characterized by westward flow and an orbital phase curve that peaks after secondary eclipse (in contrast to all of our other models), while the quickly rotating model has a net Doppler shift that is more strongly blueshifted than the other models. Our results demonstrate that the combined use of these two techniques may be a fruitful way to constrain the rotation rate of some planets and motivate future work on this topic.},
doi = {10.1088/0004-637X/790/1/79},
journal = {Astrophysical Journal},
number = 1,
volume = 790,
place = {United States},
year = {Sun Jul 20 00:00:00 EDT 2014},
month = {Sun Jul 20 00:00:00 EDT 2014}
}
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