dc.contributor.author | Tremblin, P | |
dc.contributor.author | Chabrier, G | |
dc.contributor.author | Baraffe, I | |
dc.contributor.author | Liu, MC | |
dc.contributor.author | Magnier, EA | |
dc.contributor.author | Lagage, P-O | |
dc.contributor.author | Oliveira, CAD | |
dc.contributor.author | Burgasser, AJ | |
dc.contributor.author | Amundsen, DS | |
dc.contributor.author | Drummond, B | |
dc.date.accessioned | 2017-10-31T09:45:03Z | |
dc.date.issued | 2017-11-15 | |
dc.description.abstract | Atmospheric modeling of low-gravity (VL-G) young brown dwarfs remains a challenge. The presence of very thick clouds has been suggested because of their extremely red near-infrared (NIR) spectra, but no cloud models provide a good fit to the data with a radius compatible with evolutionary models for these objects. We show that cloudless atmospheres assuming a temperature gradient reduction caused by fingering convection provides a very good model to match the observed VL-G NIR spectra. The sequence of extremely red colors in the NIR for atmospheres with effective temperature from ~2000 K down to ~1200 K is very well reproduced with predicted radii typical of young low-gravity objects. Future observations with NIRSPEC and MIRI on the James Webb Space Telescope (JWST) will provide more constrains in the mid-infrared, helping to confirm/refute whether or not the NIR reddening is caused by fingering convection. We suggest that the presence/absence of clouds will be directly determined by the silicate absorption features that can be observed with MIRI. JWST will therefore be able to better characterize the atmosphere of these hot young brown dwarfs and their low-gravity exoplanet analogues. | en_GB |
dc.description.sponsorship | This work is partly supported by the European Research
Council under the European Community’s Seventh Framework
Programme (FP7/2007-2013 Grant Agreement No.
247060-PEPS and grant No. 320478-TOFU). MCL acknowledges
support from NSF grant AST-1518339. POL acknowledges
support from the LabEx P2IO, the French ANR contract
05-BLAN-NT09-573739. | en_GB |
dc.identifier.citation | Vol. 850 (1), article 46 | en_GB |
dc.identifier.doi | 10.3847/1538-4357/aa9214 | |
dc.identifier.uri | http://hdl.handle.net/10871/30075 | |
dc.language.iso | en | en_GB |
dc.publisher | American Astronomical Society / IOP Publishing | en_GB |
dc.rights | © 2017. The American Astronomical Society. All rights reserved. | |
dc.subject | Methods: observational | en_GB |
dc.subject | Methods: numerical | en_GB |
dc.subject | brown dwarfs | en_GB |
dc.subject | planets and satellites: atmospheres | en_GB |
dc.title | Cloudless atmospheres for young low-gravity substellar objects | en_GB |
dc.type | Article | en_GB |
dc.description | This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record. | en_GB |
dc.identifier.eissn | 1538-4357 | |
dc.identifier.journal | Astrophysical Journal | en_GB |