Discovery of New Ultracool White Dwarfs in the Sloan Digital Sky Survey
Abstract
We report the discovery of five new white dwarfs in the Sloan Digital Sky Survey. Four are ultracool, exhibiting strong collision-induced absorption (CIA) from molecular hydrogen and are similar in color to the three previously known coolest white dwarfs, SDSS J1337+00, LHS 3250, and LHS 1402. The fifth star shows milder CIA flux suppression and has a color and spectral shape similar to WD 0346+246. All five new white dwarfs are faint (g>18.9) and have significant proper motions. One of the new ultracool white dwarfs, SDSS J0947, appears to be in a binary system with a slightly warmer (Teff~5000 K) white dwarf companion.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 2004
- DOI:
- 10.1086/424568
- arXiv:
- arXiv:astro-ph/0405566
- Bibcode:
- 2004ApJ...612L.129G
- Keywords:
-
- Stars: Individual: Alphanumeric: SDSS J0854+35;
- Stars: Individual: Alphanumeric: SDSS J0947+44;
- Stars: Individual: Alphanumeric: SDSS J1001+39;
- Stars: Individual: Alphanumeric: SDSS J1220+09;
- Stars: Individual: Alphanumeric: SDSS J1403+45;
- Stars: White Dwarfs;
- Astrophysics
- E-Print:
- 15 pages, 3 figures, submitted to ApJL. Higher resolution versions of finding charts are available at http://astro.uchicago.edu/~gates/findingcharts
