NOAO > Observing Info > Approved Programs > 2012B-0424
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NOAO > Observing Info > Approved Programs > 2012B-0424 |
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PI: John Gizis, University of Delaware, gizis@udel.edu
Address: Department of Physics and Astronomy, 217 Sharp Lab, Newark, DE 19716, USA
CoI: Philip Castro, University of Delaware
Title: Completing the nearby L dwarf sample
Abstract:
We are using the WISE and 2MASS infrared sky survey to identify
nearby bright L-type brown dwarfs close to the Galactic Plane, where
2MASS or SDSS-based surveys could not reliably identify them. In this
proposal, we request optical spectroscopy of ten new bright L dwarfs,
which will serve as new standards for detailed studies of substellar
objects. We argue that optical spectroscopy provides important
information that cannot be determined from near-infrared spectroscopy we
have already obtained: The optical features are better temperature
indicators, lithium is a mass/age indicator, H alpha is a chromospheric
activity indicator, and the molecular bandheads are sensitive to surface
gravity. Our targets include the reddest field L dwarf known, which
uniquely proves extremely cloudy substellar atmospheric conditions, and
the two closest L7-L8 dwarfs in the northern hemisphere.
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 > 2012B-0424 |
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