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Parallaxes of Brown Dwarfs at USNO

Published online by Cambridge University Press:  26 May 2016

Hugh C. Harris
Affiliation:
U. S. Naval Observatory, P.O. Box 1149, Flagstaff, AZ 86002-1149
Conard C. Dahn
Affiliation:
U. S. Naval Observatory, P.O. Box 1149, Flagstaff, AZ 86002-1149
Frederick J. Vrba
Affiliation:
U. S. Naval Observatory, P.O. Box 1149, Flagstaff, AZ 86002-1149
Harry H. Guetter
Affiliation:
U. S. Naval Observatory, P.O. Box 1149, Flagstaff, AZ 86002-1149
Blaise Canzian
Affiliation:
U. S. Naval Observatory, P.O. Box 1149, Flagstaff, AZ 86002-1149
Arne A. Henden
Affiliation:
U. S. Naval Observatory, P.O. Box 1149, Flagstaff, AZ 86002-1149
Stephen E. Levine
Affiliation:
U. S. Naval Observatory, P.O. Box 1149, Flagstaff, AZ 86002-1149
Christian B. Luginbuhl
Affiliation:
U. S. Naval Observatory, P.O. Box 1149, Flagstaff, AZ 86002-1149
Alice K. B. Monet
Affiliation:
U. S. Naval Observatory, P.O. Box 1149, Flagstaff, AZ 86002-1149
David G. Monet
Affiliation:
U. S. Naval Observatory, P.O. Box 1149, Flagstaff, AZ 86002-1149
Jeffery R. Pier
Affiliation:
U. S. Naval Observatory, P.O. Box 1149, Flagstaff, AZ 86002-1149
Ronald C. Stone
Affiliation:
U. S. Naval Observatory, P.O. Box 1149, Flagstaff, AZ 86002-1149
Richard L. Walker
Affiliation:
U. S. Naval Observatory, P.O. Box 1149, Flagstaff, AZ 86002-1149

Abstract

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Trigonometric parallaxes have been measured by Dahn et al. (2002) for 28 cool dwarfs and brown dwarfs, including 17 L dwarfs and three T dwarfs. Broadband CCD and near-IR photometry (VRIz*JHK) have been obtained for these objects and for 24 additional late-type dwarfs. These data have been supplemented with astrometry and photometry from the literature, including parallaxes for the brighter companions of ten L and two T dwarfs. The absolute magnitudes and colors are reviewed here. The I - J color and the spectral type are both good predictors of absolute magnitude for late-M and L dwarfs. MJ becomes monotonically fainter with I - J color and with spectral type through late-L dwarfs, then brightens for early-T dwarfs. In contrast, the J - K color correlates poorly with absolute magnitude for L dwarfs. Using several other parameters from the literature (Li detection, Hα emission strength, projected rotation velocity, and tangential velocity), we fail to uncover any measurable parameter that correlates with the anomalous J - K color.

Type
Part 7. Atmospheres and Internal Structure
Copyright
Copyright © Astronomical Society of the Pacific 2001 

References

Ackerman, A., & Marley, M. 2001, ApJ, 556, 872 Google Scholar
Basri, G. 2001, in ASP Conf. Ser. 223, 11th Cool Stars Workshop, eds. García-López, R. Rebolo, & Zapatero-Osorio, M.R., (San Francisco: ASP), 261 Google Scholar
Basri, G., Mohanty, S., Allard, F., Hauschildt, P.H., Delfosse, X., Martín, E.L., Forveille, T., & Goldman, B. 2000, ApJ, 538, 363 Google Scholar
Burrows, A., Burgasser, A.J., Kirkpatrick, J.D., Liebert, J., Milsom, J.A., Sudarsky, M.D., & Hubeny, I. 2002, ApJ, 573, 394 Google Scholar
Dahn, C.C., et al. 2002, AJ, 124, 1170 Google Scholar
Leggett, S.K., et al. 2002, ApJ, 564, 452 Google Scholar
Kirkpatrick, J.D., et al. 1999, ApJ, 519, 802 Google Scholar
Kirkpatrick, J.D., et al. 2000, AJ, 120, 477 Google Scholar
Kirkpatrick, J.D., Dahn, C.C., Monet, D.G., Reid, I.N., Gizis, J.E., Liebert, J., & Burgasser, A.J. 2001, AJ, 121, 3235 Google Scholar
Martín, E.L., Delfosse, X., Basri, G., Goldman, B., Forveille, T., & Zapatero Osorio, M.R. 1999, AJ, 118, 2466 Google Scholar
Reid, I.N., Kirkpatrick, J.D., Liebert, J., Gizis, J.E., Dahn, C.C., & Monet, D.G. 2002, AJ, 124, in press, astro-ph/0204285 Google Scholar
Tinney, C.G. & Reid, I.N. 1998, MNRAS, 301, 1031 CrossRefGoogle Scholar
Tsuji, T. 2002, ApJ, 575, 264 CrossRefGoogle Scholar