TY - JOUR
T1 - Detection of thermal emission of XO-2b
T2 - Evidence for a weak temperature inversion
AU - MacHalek, Pavel
AU - McCullough, Peter R.
AU - Burrows, Adam
AU - Burke, Christopher J.
AU - Hora, Joseph L.
AU - Johns-Krull, Christopher M.
PY - 2009
Y1 - 2009
N2 - We estimate flux ratios of the extrasolar planet XO-2b to its host star XO-2 at 3.6, 4.5, 5.8, and 8.0 μm with Infrared Array Camera on the Spitzer Space Telescope to be 0.00081 ± 0.00017, 0.00098 ± 0.00020, 0.00167 ± 0.00036, and 0.00133 ± 0.00049, respectively. The fluxes provide tentative evidence for a weak temperature inversion in the upper atmosphere, the precise nature of which would need to be confirmed by longer wavelength observations. XO-2b substellar flux of 0.76 × 109 erg cm-2 s-1 lies in the predicted transition region between atmospheres with and without upper atmospheric temperature inversion.
AB - We estimate flux ratios of the extrasolar planet XO-2b to its host star XO-2 at 3.6, 4.5, 5.8, and 8.0 μm with Infrared Array Camera on the Spitzer Space Telescope to be 0.00081 ± 0.00017, 0.00098 ± 0.00020, 0.00167 ± 0.00036, and 0.00133 ± 0.00049, respectively. The fluxes provide tentative evidence for a weak temperature inversion in the upper atmosphere, the precise nature of which would need to be confirmed by longer wavelength observations. XO-2b substellar flux of 0.76 × 109 erg cm-2 s-1 lies in the predicted transition region between atmospheres with and without upper atmospheric temperature inversion.
KW - Binaries: eclipsing
KW - Infrared: stars
KW - Planetary systems
KW - Stars: individual (XO-2)
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U2 - 10.1088/0004-637X/701/1/514
DO - 10.1088/0004-637X/701/1/514
M3 - Article
AN - SCOPUS:70449814692
SN - 0004-637X
VL - 701
SP - 514
EP - 520
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 1
ER -