NOAO > Observing Info > Approved Programs > 2013A-0269
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NOAO > Observing Info > Approved Programs > 2013A-0269 |
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PI: Sandy Leggett, Gemini Observatory, sleggett@gemini.edu
Address: Gemini Observatory, 670 N. Aohoku Place, Hilo, HI 96720, USA
CoI: Jonathan Fortney, UC Santa Cruz
CoI: Mark Marley, NASA Ames
CoI: Caroline Morley, UC Santa Cruz
CoI: Didier Saumon, Los Alamos National Lab
CoI: Channon Visscher, Southwest Research Institute
Title: Near-Infrared Characterization of Y Dwarfs
Abstract:
Extremely low-temperature brown dwarfs, the prototype Y dwarfs, have recently
been discovered in 5 micron images obtained by WISE . We have shown that our
models which include chloride and sulfide clouds are successful at
reproducing the energy distributions of brown dwarfs with T_eff between 400K
and 800K (Y0 to T8 spectral types). We are working on cooler models which
incorporate water clouds. NIRI photometry obtained in 12A and 12B indicates
problems with previously published Palomar photometry. We have used the NIRI
data and our models to constrain temperature, mass and age for the first WISE
Y dwarfs: 300 to 450K, 5 to 10 Jupiter masses, and 1 to 5 Gyr. We request
time to obtain NIRI photometry of two new WISE 400K dwarfs, and additional
data for two 300-350K WISE dwarfs. We will also observe a WISE T9 dwarf with
apparently odd colors. These data will allow us to examine the distribution
in temperature, gravity and cloudiness for 400K objects, and constrain our
new water cloud models for 300K objects. The new model suite will enable
detailed study of brown dwarfs and gas giant exoplanets at nearly all
relevant T_eff, including those found at Gemini by GPI.
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360
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NOAO > Observing Info > Approved Programs > 2013A-0269 |
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