Fraine, Jonathan D.; Deming, Drake; Gillon, Michaël; Jehin, Emmanuël; Demory, Brice-Olivier; Benneke, Bjoern; Seager, Sara; Lewis, Nikole K.; Knutson, Heather; Désert, Jean-Michel (2013). SPITZER TRANSITS OF THE SUPER-EARTH GJ1214b AND IMPLICATIONS FOR ITS ATMOSPHERE. Astrophysical journal, 765(2), p. 127. Institute of Physics Publishing IOP 10.1088/0004-637x/765/2/127
|
Text
Fraine_2013_ApJ_765_127.pdf - Published Version Available under License Publisher holds Copyright. Download (9MB) | Preview |
We observed the transiting super-Earth exoplanet GJ1214b using warm Spitzer at 4.5 μm wavelength during a 20 day quasi-continuous sequence in 2011 May. The goals of our long observation were to accurately define the infrared transit radius of this nearby super-Earth, to search for the secondary eclipse, and to search for other transiting planets in the habitable zone of GJ1214. We here report results from the transit monitoring of GJ1214b, including a reanalysis of previous transit observations by Désert et al. In total, we analyze 14 transits of GJ1214b at 4.5 μm, 3 transits at 3.6 μm, and 7 new ground-based transits in the I+z band. Our new Spitzer data by themselves eliminate cloudless solar composition atmospheres for GJ1214b, and methane-rich models from Howe & Burrows. Using our new Spitzer measurements to anchor the observed transit radii of GJ1214b at long wavelengths, and adding new measurements in I+z, we evaluate models from Benneke & Seager and Howe & Burrows using a χ2 analysis. We find that the best-fit model exhibits an increase in transit radius at short wavelengths due to Rayleigh scattering. Pure water atmospheres are also possible. However, a flat line (no atmosphere detected) remains among the best of the statistically acceptable models, and better than pure water atmospheres. We explore the effect of systematic differences among results from different observational groups, and we find that the Howe & Burrows tholin-haze model remains the best fit, even when systematic differences among observers are considered.
Item Type: |
Journal Article (Original Article) |
|---|---|
Division/Institute: |
10 Strategic Research Centers > Center for Space and Habitability (CSH) |
UniBE Contributor: |
Demory, Brice-Olivier Denys |
Subjects: |
500 Science > 520 Astronomy |
ISSN: |
0004-637X |
Publisher: |
Institute of Physics Publishing IOP |
Language: |
English |
Submitter: |
Brice-Olivier Denys Demory |
Date Deposited: |
06 Apr 2022 10:41 |
Last Modified: |
02 Mar 2023 23:34 |
Publisher DOI: |
10.1088/0004-637x/765/2/127 |
BORIS DOI: |
10.48350/153311 |
URI: |
https://boris.unibe.ch/id/eprint/153311 |
Actions (login required)
 |
Edit item |