PI: John Gizis, University of Delaware, email@example.com
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.
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