On the Interpretation of High‐Velocity White Dwarfs as Members of the Galactic Halo
Open Access
- 1 June 2005
- journal article
- research article
- Published by American Astronomical Society in The Astrophysical Journal
- Vol. 625 (2), 838-848
- https://doi.org/10.1086/429715
Abstract
A detailed analysis of 32 of the 38 halo white dwarf candidates identified by Oppenheimer et al. is presented, based on model atmosphere fits to observed energy distributions built from optical BVRI and infrared JHK CCD photometry. Effective temperatures and atmospheric compositions are determined for all objects, as well as masses and cooling ages when trigonometric parallax measurements are available. This sample is combined with that of other halo white dwarf candidates and disk white dwarfs to study the nature of these objects in terms of reduced proper motion diagrams, tangential velocities, and stellar ages. We reaffirm the conclusions of an earlier analysis based on photographic magnitudes of the same sample that total stellar ages must be derived in order to associate a white dwarf with the old halo population, and that this can only be accomplished through precise mass and distance determinations.Other Versions
This publication has 40 references indexed in Scilit:
- Hubble Space TelescopeAbsolute Spectrophotometry of Vega from the Far-Ultraviolet to the InfraredThe Astronomical Journal, 2004
- A Critical Examination of Halo White Dwarf CandidatesThe Astrophysical Journal, 2003
- Model Atmosphere Analysis of Two Very Cool White DwarfsThe Astrophysical Journal, 2002
- Photometric and Spectroscopic Analysis of Cool White Dwarfs with Trigonometric Parallax MeasurementsThe Astrophysical Journal Supplement Series, 2001
- The Chemical Evolution of Cool White Dwarfs and the Age of the Local Galactic DiskThe Astrophysical Journal Supplement Series, 1997
- Photometric Calibration of Hydrogen- and Helium-Rich White Dwarf ModelsPublications of the Astronomical Society of the Pacific, 1995
- New model atmospheres for very cool white dwarfs with mixed H/He and pure He compositionsThe Astrophysical Journal, 1995
- A spectroscopic determination of the mass distribution of DA white dwarfsThe Astrophysical Journal, 1992
- UBVRI passbandsPublications of the Astronomical Society of the Pacific, 1990
- JHKLM photometry - Standard systems, passbands, and intrinsic colorsPublications of the Astronomical Society of the Pacific, 1988