J/A+A/517/A76 Near-IR spectrum of 2M1207b (Patience+, 2010)
The highest resolution near-infrared spectrum of the imaged planetary mass
companion 2M1207b.
Patience J., King R.R., De Rosa R.J., Marois C.
<Astron. Astrophys. 517, A76 (2010)>
=2010A&A...517A..76P 2010A&A...517A..76P
ADC_Keywords: Stars, nearby ; Planets ; Spectra, infrared
Keywords: planetary systems - brown dwarfs -
planets and satellites: atmospheres - binaries: close -
techniques: high angular resolution
Abstract:
Direct-imaging searches for planets reveal wide orbit planets amenable
to spectroscopy, and their atmospheres represent an important
comparison to the irradiated atmospheres of Hot Jupiters. Using AO
integral field spectroscopy of 2M1207b, the shape of the continuum
emission over the J, H, and K bands from the atmosphere of this young,
planetary mass companion is measured in order to compare with
atmospheric and evolutionary models, and objects of similar
temperature in young clusters and the field. The 2M1207b spectrum has
the highest spectral resolution (R∼300-1500) and largest wavelength
coverage, including the first J-band spectrum, for this benchmark
object. The high signal-to-noise of the data allow a clear
identification of signatures of low surface gravity, and comparison
with a grid of AMES-Dusty models reveals a best-fit effective
temperature of Teff=1600K with a preferred surface gravity of
logg=4.5. The J-band flux is depressed relative to nearly all L-type
objects, and the detailed shape of the absorption features across the
H-band exhibit differences from the model predictions. The possible
origins of 2M1207b and its low luminosity are examined with the new
data and analysis which suggest that extinction from a disk with large
grains is a viable scenario and is preferred over scattering off an
optically thick disk. The 2M1207b spectrum presents an important
comparison for the types of features which may be present in upcoming
spectra of the atmospheres of planets imaged in orbit around stellar
primaries.
Description:
Near-IR spectroscopy of the planetary-mass companion to 2M1207. These
observations were made with the ESO VLT SINFONI spectrograph. The
flux has been scaled by the J and K-band photometry in the J and HK
spectral orders. In regions of high telluric absorption the data have
been masked and flux set to zero.
Objects:
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RA (2000) DE Designation(s)
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12 07 33.5 -39 32 54 2M1207 = 2MASSW J1207334-393254
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
2m1207b.dat 25 2491 Near-IR spectrum of 2M1207b
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See also:
J/ApJ/646/505 : Catalog of nearby exoplanets (Butler+, 2006)
Byte-by-byte Description of file: 2m1207b.dat
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Bytes Format Units Label Explanations
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3- 10 F8.6 um lambda [1.088/2.493] Wavelength
16- 25 E10.5 W/m2/um Flux Flux (Flambda)
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Acknowledgements:
Jenny Patience, patience(at)astro.ex.ac.uk
(End) Patricia Vannier [CDS] 09-Aug-2010