Cool White Dwarfs Revisited: New Spectroscopy and Photometry

@article{Salim2004CoolWD,
  title={Cool White Dwarfs Revisited: New Spectroscopy and Photometry},
  author={Samir Salim and R. Michael Rich and Brad M S Hansen and L{\'e}on V. E. Koopmans and Ben R. Oppenheimer and Roger D.Blandford},
  journal={The Astrophysical Journal},
  year={2004},
  volume={601},
  pages={1075-1087}
}
In this paper we present new and improved data on 38 cool white dwarfs identified in 2001 by Oppenheimer and coworkers as candidate dark-halo objects. Using the high-resolution spectra obtained with LRIS on Keck I, we measure precise radial velocities for 13 white dwarfs that show an Hα absorption line. We show that accounting for radial velocities on average decreases the U-V plane velocities by only 6%. In two cases, accounting for the radial velocities put original halo candidates below the… Expand
On the Interpretation of High-Velocity White Dwarfs as Members of the Galactic Halo
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 BVRIExpand
3D kinematics of white dwarfs from the SPY project
We present the kinematics of a sample of 398 DA white dwarfs from the SPY project (ESO SN Ia Progenitor surveY) and discuss kinematic criteria for distinguishing thin-disk, thick-disk, and haloExpand
The Solar Neighborhood. XIX. Discovery and Characterization of 33 New Nearby White Dwarf Systems
We present spectra for 33 previously unclassified white dwarf systems brighter than V = 17 primarily in the southern hemisphere. Of these new systems, 26 are DA, 4 are DC, 2 are DZ, and 1 is DQ. WeExpand
A new ultracool white dwarf discovered in the SuperCOSMOS Sky Survey
We present BJ, R59F and IN photometry, and optical and near-infrared spectroscopy, of a new ultracool white dwarf (UCWD) discovered in the SuperCOSMOS Sky Survey. The spectrum of SSS J1556−0806 showsExpand
Additional Ultracool White Dwarfs Found in the Sloan Digital Sky Survey
We identify seven new ultracool white dwarfs discovered in the Sloan Digital Sky Survey (SDSS). The SDSS photometry, spectra, and proper motions are presented, and additional BVRI data are given forExpand
HIGH-VELOCITY WHITE DWARFS AND GALACTIC STRUCTURE
▪ Abstract A number of recent investigations suggest that cool white dwarfs are more numerous than predicted by conventional Galactic models and that those stars make a significant contribution toExpand
Disk or halo white dwarfs? Kinematic analysis of high proper motion surveys
We present an alternative method for the kinematic analysis of high proper motion surveys and discuss its application to the survey of Oppenheimer et al. (2001) for the selection of reliable haloExpand
3D kinematics of white dwarfs from the SPY project
We present kinematics of a sample of 107 DA white dwarfs from the SPY project (ESO SN Ia Progenitor surveY) and discuss kinematic criteria for a distinction of thin disk, thick disk, and haloExpand
Discovery of a Possible Cool White Dwarf Companion from the AllWISE Motion Survey
We present optical and near-infrared spectroscopy of WISEA J061543.91$-$124726.8, which we rediscovered as a high motion object in the AllWISE survey. The spectra of this object are unusual; whileExpand
White dwarfs in the SuperCOSMOS Sky Survey
We present a magnitude and proper motion limited catalogue of ∼10 000 white dwarf candidates, obtained from the SuperCOSMOS Sky Survey by means of reduced proper motion selection. This catalogueExpand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 41 REFERENCES
Wide Binary Systems and the Nature of High-Velocity White Dwarfs
We present measured radial velocities and complete space motions for 116 white dwarf stars with M dwarf companions. Thirteen pairs have "halo-like" velocities. According to a recent study byExpand
High-Velocity White Dwarfs: Thick Disk, Not Dark Matter
We present an alternative interpretation of the nature of the extremely cool, high-velocity white dwarfs identified by Oppenheimer et al. in a high-latitude astrometric survey. We argue that theExpand
Photometric and Spectroscopic Analysis of Cool White Dwarfs with Trigonometric Parallax Measurements
A detailed photometric and spectroscopic analysis of cool (Teff 12,000 K) white dwarf stars is presented. The sample has been drawn from the Yale Parallax Catalog and from a proper motion survey inExpand
Pure Hydrogen Model Atmospheres for Very Cool White Dwarfs
Microlensing events observed in the line of sight toward the LMC indicate that a significant fraction of the mass of the dark halo of the Galaxy is probably composed of white dwarfs. In addition,Expand
A Critical Examination of Halo White Dwarf Candidates
A detailed analysis of halo white dwarf candidates is presented, which is based on model atmosphere fits to observed energy distributions built from photoelectric or photographic magnitudes. Most ofExpand
The Chemical Evolution of Cool White Dwarfs and the Age of the Local Galactic Disk
Photometric and spectroscopic observations of 110 cool white dwarf stars are presented and analyzed with state-of-the-art model atmosphere calculations appropriate for cool white dwarfs with pureExpand
White Dwarfs in Common Proper Motion Binary Systems: Mass Distribution and Kinematics
We present the mass distribution, gravitational redshifts, radial velocities, and space motions of white dwarf stars in common proper motion binary systems. The mass distribution we derive for the 41Expand
3D kinematics of white dwarfs from the SPY project
We present kinematics of a sample of 107 DA white dwarfs from the SPY project (ESO SN Ia Progenitor surveY) and discuss kinematic criteria for a distinction of thin disk, thick disk, and haloExpand
Kinematics of Metal-poor Stars in the Galaxy. III. Formation of the Stellar Halo and Thick Disk as Revealed from a Large Sample of Nonkinematically Selected Stars
We present a detailed analysis of the space motions of 1203 solar-neighborhood stars with metal abundances [Fe/H] ≤ -0.6, on the basis of a catalog, of metal-poor stars selected without kinematicExpand
An Initial Survey of White Dwarfs in the Sloan Digital Sky Survey
An initial assessment is made of white dwarf and hot subdwarf stars observed in the Sloan Digital Sky Survey. In a small area of sky (190 square degrees), observed much like the full survey will be,Expand
...
1
2
3
4
5
...