The Discovery of Two Nearby Carbon Dwarfs

Abstract

The comparison of optical and 2MASS near-infrared photometry for large samples of catalogued proper motion stars has the potential to discover previously unrecognized nearby objects of rare type. In this paper we present the discovery of two new carbon dwarfs, LSR 2105+2514 and LP 758-43, which were drawn from proper motion lists and which lie in a sparsely populated part of optical/near-IR color-color space. Their optical spectra, exhibiting absorptions by C_2 and/or CN, are discussed. LSR 2105+2514 is believed to lie within 200 pc and would have M_(K_s) < 6.7, making it lower in luminosity than any carbon dwarf with a measured trigonometric parallax. LP 758-43, which is not as red but still probably cooler than the best studied carbon dwarfs, is believed to lie within 360 pc. Using our optical/near-infrared selection technique on published lists of proper motion stars, we hope in the near future to expand further the current sample of carbon dwarfs, which numbers only 31 objects at this writing.

arXiv comment6 pages, 4 figs, Accepted by ApJ Letters

References in corpus (5)

• Improved Astrometry and Photometry for the Luyten Catalog. II. Faint Stars and the Revised Catalog
• New High Proper Motion Stars from the Digitized Sky Survey. I. Northern Stars with proper motion between 0.5 and 2.0 arcsec/yr at Low Galactic Latitudes
• The APM Survey for Cool Carbon Stars in the Galactic Halo - II The Search for Dwarf Carbon Stars
• Faint High Latitude Carbon Stars Discovered by the Sloan Digital Sky Survey: Methods and Initial Results
• Astrometry and Photometry for Two Dwarf Carbon Stars

Cited by in corpus (13)

• The Taurus Spitzer Survey: New Candidate Taurus Members Selected Using Sensitive Mid-Infrared Photometry
• Faint High-Latitude Carbon Stars Discovered by the Sloan Digital Sky Survey: An Initial Catalog
• A Survey for Low-Mass Stars and Brown Dwarfs in the Eta Cha and Eps Cha Young Associations
• Cool carbon stars in the halo: a new survey based on 2MASS
• A spectroscopic and proper motion search of Sloan digital Sky Survey: red subdwarfs in binary systems
• The CH fraction of Carbon stars at high Galactic latitudes
• Identifying Ultra-Cool Dwarfs at Low Galactic Latitudes: A Southern Candidate Catalogue
• Cool carbon stars in the halo II. A study of 25 new objects
• Dwarf carbon stars are likely metal-poor binaries and unlikely hosts to carbon planets
• Evidence for Halo Kinematics among Cool Carbon-Rich Dwarfs
• Meeting the Cool Neighbours, VI: A search for nearby ultracool dwarfs in the Galactic Plane
• Carbon-enhanced stars with short orbital and spin periods
• Revised classification of the SBS carbon star candidates including the discovery of a new emission line dwarf carbon star