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Title: A 2MASS/AllWISE Search for Extremely Red L Dwarfs: The Discovery of Several Likely L Type Members of β Pic, AB Dor, Tuc-Hor, Argus, and the Hyades

Abstract

Young brown dwarfs share many properties with directly imaged giant extrasolar planets. They therefore provide unique laboratories for investigating the full range of temperature and mass encompassed by the growing collection of planets discovered outside our Solar System. Furthermore, if they can be tied to a particular group of coeval stars, they also provide vital anchor points for low-mass empirical isochrones. We have developed a novel procedure for identifying such objects based on their unique 2MASS and AllWISE colors. Using our search criteria, we have identified 50 new, late-type L dwarf candidates, 47 of which are spectroscopically confirmed as L dwarfs with follow-up near-infrared spectroscopy. We evaluate the potential membership of these objects in nearby, young moving groups using their proper motions, photometric distance estimates, and spectroscopic indicators of youth, and find seven likely L-type members belonging to the β Pictoris moving group, the AB Doradus moving group, the Tucana-Horologium association, or the Argus association, in addition to several lower probability members. Also found are two late-type (L5 and L6) potential members of the nearby Hyades cluster (WISEA J043642.75+190134.8 and WISEA J044105.56+213001.5).

Authors:
;  [1]; ;  [2];  [3]
  1. School of Earth and Space Exploration, Arizona State University, Tempe, AZ, 85282 (United States)
  2. Department of Physics and Astronomy, University of Toledo, 2801 W. Bancroft Street, Toledo, OH 43606 (United States)
  3. IPAC, Mail Code 100-22, Caltech, 1200 E. California Boulevard, Pasadena, CA 91125 (United States)
Publication Date:
OSTI Identifier:
22663712
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (Online); Journal Volume: 153; Journal Issue: 4; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABSORPTION SPECTROSCOPY; COLOR; DISTANCE; DWARF STARS; INDICATORS; INFRARED SPECTRA; MASS; NEAR INFRARED RADIATION; PLANETS; PROPER MOTION; SOLAR SYSTEM

Citation Formats

Schneider, Adam C., Shkolnik, Evgenya L., Windsor, James, Cushing, Michael C., and Kirkpatrick, J. Davy, E-mail: aschneid10@gmail.com. A 2MASS/AllWISE Search for Extremely Red L Dwarfs: The Discovery of Several Likely L Type Members of β Pic, AB Dor, Tuc-Hor, Argus, and the Hyades. United States: N. p., 2017. Web. doi:10.3847/1538-3881/AA6624.
Schneider, Adam C., Shkolnik, Evgenya L., Windsor, James, Cushing, Michael C., & Kirkpatrick, J. Davy, E-mail: aschneid10@gmail.com. A 2MASS/AllWISE Search for Extremely Red L Dwarfs: The Discovery of Several Likely L Type Members of β Pic, AB Dor, Tuc-Hor, Argus, and the Hyades. United States. doi:10.3847/1538-3881/AA6624.
Schneider, Adam C., Shkolnik, Evgenya L., Windsor, James, Cushing, Michael C., and Kirkpatrick, J. Davy, E-mail: aschneid10@gmail.com. Sat . "A 2MASS/AllWISE Search for Extremely Red L Dwarfs: The Discovery of Several Likely L Type Members of β Pic, AB Dor, Tuc-Hor, Argus, and the Hyades". United States. doi:10.3847/1538-3881/AA6624.
@article{osti_22663712,
title = {A 2MASS/AllWISE Search for Extremely Red L Dwarfs: The Discovery of Several Likely L Type Members of β Pic, AB Dor, Tuc-Hor, Argus, and the Hyades},
author = {Schneider, Adam C. and Shkolnik, Evgenya L. and Windsor, James and Cushing, Michael C. and Kirkpatrick, J. Davy, E-mail: aschneid10@gmail.com},
abstractNote = {Young brown dwarfs share many properties with directly imaged giant extrasolar planets. They therefore provide unique laboratories for investigating the full range of temperature and mass encompassed by the growing collection of planets discovered outside our Solar System. Furthermore, if they can be tied to a particular group of coeval stars, they also provide vital anchor points for low-mass empirical isochrones. We have developed a novel procedure for identifying such objects based on their unique 2MASS and AllWISE colors. Using our search criteria, we have identified 50 new, late-type L dwarf candidates, 47 of which are spectroscopically confirmed as L dwarfs with follow-up near-infrared spectroscopy. We evaluate the potential membership of these objects in nearby, young moving groups using their proper motions, photometric distance estimates, and spectroscopic indicators of youth, and find seven likely L-type members belonging to the β Pictoris moving group, the AB Doradus moving group, the Tucana-Horologium association, or the Argus association, in addition to several lower probability members. Also found are two late-type (L5 and L6) potential members of the nearby Hyades cluster (WISEA J043642.75+190134.8 and WISEA J044105.56+213001.5).},
doi = {10.3847/1538-3881/AA6624},
journal = {Astronomical Journal (Online)},
number = 4,
volume = 153,
place = {United States},
year = {Sat Apr 01 00:00:00 EDT 2017},
month = {Sat Apr 01 00:00:00 EDT 2017}
}
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