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arXiv · 1603.08040

The AllWISE Motion Survey, Part 2

Abstract

We use the AllWISE Data Release to continue our search for WISE-detected motions. In this paper, we publish another 27,846 motion objects, bringing the total number to 48,000 when objects found during our original AllWISE motion survey are included. We use this list, along with the lists of confirmed WISE-based motion objects from the recent papers by Luhman and by Schneider et al. and candidate motion objects from the recent paper by Gagne et al. to search for widely separated, common-proper-motion systems. We identify 1,039 such candidate systems. All 48,000 objects are further analyzed using color-color and color-mag plots to provide possible characterizations prior to spectroscopic follow-up. We present spectra of 172 of these, supplemented with new spectra of 23 comparison objects from the literature, and provide classifications and physical interpretations of interesting sources. Highlights include: (1) the identification of three G/K dwarfs that can be used as standard candles to study clumpiness and grain size in nearby molecular clouds because these objects are currently moving behind the clouds, (2) the confirmation/discovery of several M, L, and T dwarfs and one white dwarf whose spectrophotometric distance estimates place them 5-20 pc from the Sun, (3) the suggestion that the Na 'D' line be used as a diagnostic tool for interpreting and classifying metal-poor late-M and L dwarfs, (4) the recognition of a triple system including a carbon dwarf and late-M subdwarf, for which model fits of the late-M subdwarf (giving [Fe/H] ~ -1.0) provide a measured metallicity for the carbon star, and (5) a possible 24-pc-distant K5 dwarf + peculiar red L5 system with an apparent physical separation of 0.1 pc.

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BibTeXRIS

J. Davy Kirkpatrick, Kendra Kellogg, Adam C. Schneider, Sergio Fajardo-Acosta, Michael C. Cushing, Jennifer Greco, Gregory N. Mace, Christopher R. Gelino, Edward L. Wright, Peter R. M. Eisenhardt, Daniel Stern, Jacqueline K. Faherty, Scott S. Sheppard, George B. Lansbury, Sarah E. Logsdon, Emily C. Martin, Ian S. McLean, Steven D. Schurr, Roc M. Cutri, Tim Conrow. 2016-03-25. The AllWISE Motion Survey, Part 2. https://doi.org/10.3847/0067-0049/224/2/36

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