CCD Parallaxes for 309 Late-type Dwarfs and Subdwarfs
Abstract
New, updated, and/or revised CCD parallaxes determined with the Strand Astrometric Reflector at the Naval Observatory Flagstaff Station (NOFS) are presented. Included are results for 309 late-type dwarf and subdwarf stars observed over the 30+ years that the program operated. For 124 of the stars, parallax determinations from other investigators have already appeared in the literature and we compare the different results. Also included here is new or updated photometry on the Johnson-Kron-Cousins system for all but a few of the faintest targets. Together with 2MASS near-infrared photometry, a sample of absolute magnitude versus color and color versus color diagrams are constructed. Since large proper motion was a prime criterion for targeting the stars, the majority turn out to be either M-type subdwarfs or late M-type dwarfs. The sample also includes 50 dwarf or subdwarf L-type stars, and four T dwarfs. Possible halo subdwarfs are identified in the sample based on tangential velocity, subluminosity, and spectral type. Residuals from the solutions for parallax and proper motion for several stars show evidence of astrometric perturbations.
Keywords
Cite
@article{arxiv.1709.02729,
title = {CCD Parallaxes for 309 Late-type Dwarfs and Subdwarfs},
author = {Conard C. Dahn and Hugh C. Harris and John P. Subasavage and Harold D. Ables and Blaise J. Canzian and Harry H. Guetter and Fred H. Harris and Arne H. Henden and S. K. Leggett and Stephen E. Levine and Christian B. Luginbuhl and Alice B. Monet and David G. Monet and Jeffrey A. Munn and Jeffrey R. Pier and Ronald C. Stone and Frederick J. Vrba and Richard L. Walker and Trudy M. Tilleman},
journal= {arXiv preprint arXiv:1709.02729},
year = {2017}
}
Comments
Machine-readable tables are available as supplemental material (click on "Other Formats" to access)