J/AJ/124/1118 Radial velocities of high-velocity white dwarfs (Silvestri+, 2002)
Wide binary systems and the nature of high-velocity white dwarfs.
Silvestri N.M., Oswalt T.D., Hawley S.L.
<Astron. J. 124, 1118 (2002)>
=2002AJ....124.1118S 2002AJ....124.1118S
ADC_Keywords: Stars, double and multiple ; Stars, white dwarf ;
Radial velocities
Keywords: binaries: general - Galaxy: disk - Galaxy: kinematics and dynamics -
stars: fundamental parameters - white dwarfs
Description:
Radial velocities and complete space motions were measured for 116
white dwarf stars with M dwarf companions (WD+M), including thirteen
pairs having "halo-like" velocities. These 116 WD+dM binaries were
observed on the 3.5 m telescope at the Apache Point Observatory (APO)
on nearly 30 half-nights between 2000 September 4 and 2001 October 20.
The APO Double Imaging Spectrograph was used with a 15" slit, yielding
a resolution of approximately 2arcsrc/pixel.
From the near-solar abundance levels of the M dwarf companions, only
one potential stellar halo white dwarf (LP 164-52) was found in the
sample, 12 of the 13 high-velocity white dwarfs being actually part of
the high-velocity tail of the thick disk rather than the dark matter
halo of the Galaxy.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 60 116 116 White Dwarfs in Common Proper Motion
Binary Systems
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- ID White dwarf identifier assigned by Luyten
11 A1 --- f_ID [b] Note on ID (1)
13- 19 F7.4 h RAhour Right Ascension (B1950)
21- 28 F8.4 deg DEdeg Declination (B1950)
30- 33 F4.2 arcsec/yr mu Total proper motion
35- 37 I3 deg PAmu Position angle of the total proper motion
39- 43 F5.1 km/s RV Measured radial velocity
45- 48 F4.1 km/s e_RV Error in RV
50- 54 F5.2 mag Vmag The V band magnitude from Smith
(1997, Ph.D. thesis, Florida Inst. Technol)
56- 59 F4.1 mag VMag Absolute V band magnitude (2)
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Note (1): b: A stellar halo white dwarf candidate.
Note (2): Determined from the atmosphere models of Bergeron, Saumon & Wesemael
(1995ApJ...443..764B 1995ApJ...443..764B) assuming a log(g)=8.0 WD.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 26-Nov-2002