Fire spectroscopy of the ultra-cool brown dwarf, UGPS J072227.51-054031.2: Kinematics, rotation and atmospheric parameters
We present λ/Δλ ~ 6000 near-infrared spectroscopy of the nearby T9 dwarf, UGPS J072227.51–054031.2, obtained during the commissioning of the Folded-Port Infrared Echellette Spectrograph on the Baade Magellan telescope at Las Campanas Observatory. The spectrum is marked by significant absorption from...
Main Authors: | , , , |
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Other Authors: | |
Format: | Article |
Language: | en_US |
Published: |
IOP Publishing
2013
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Online Access: | http://hdl.handle.net/1721.1/76694 https://orcid.org/0000-0003-3769-9559 |
Summary: | We present λ/Δλ ~ 6000 near-infrared spectroscopy of the nearby T9 dwarf, UGPS J072227.51–054031.2, obtained during the commissioning of the Folded-Port Infrared Echellette Spectrograph on the Baade Magellan telescope at Las Campanas Observatory. The spectrum is marked by significant absorption from H[subscript 2]O, CH[subscript 4], and H[subscript 2]. We also identify NH[subscript 3] absorption features by comparing the spectrum to recently published line lists. The spectrum is fit with BT-Settl models, indicating T [subscript eff] ~500-600 K and log g ~4.3-5.0. This corresponds to a mass of ~10-30 M {subscript Jup] and an age of 1-5 Gyr, however, there are large discrepancies between the model and observed spectrum. The radial and rotational velocities of the brown dwarf are measured as 46.9 ± 2.5 and 40 ± 10 km s[superscript –1], respectively, reflecting a thin disk Galactic orbit and fast rotation similar to other T dwarfs, suggesting a young, possibly planetary-mass brown dwarf. |
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