J/ApJ/643/402 Cool white dwarfs in the solar neighborhood (Kawka+, 2006)
Spectroscopic identification of cool white dwarfs in the solar neighborhood.
Kawka A., Vennes S.
<Astrophys. J., 643, 402-415 (2006)>
=2006ApJ...643..402K 2006ApJ...643..402K
ADC_Keywords: Stars, white dwarf ; Stars, nearby ; Photometry ; Space velocities
Keywords: solar neighborhood - stars: atmospheres - white dwarfs
Abstract:
The New Luyten Two-Tenths catalog contains a large number of
high proper motion white dwarf candidates that remain to be
spectroscopically confirmed. We present new spectroscopic
observations, as well as SDSS archival spectra of 49 white dwarf
candidates selected from the revised NLTT catalog of Salim & Gould
(2003, Cat. J/ApJ/582/1011). Of these, 34 are cool DA white dwarfs
with temperatures ranging from approximately 5000 up to 11,690K, and
11 are DC white dwarfs with temperatures ranging from 4300K (NLTT
18555) up to 11000K. Three of the DA white dwarfs also display
abundances of heavy elements (NLTT 3915, NLTT 44986, and NLTT 43806),
and one is a cool magnetic white dwarf (NLTT 44447) with an estimated
magnetic field strength of 1.3MG. We also present a new cool DQ white
dwarf (NLTT 31347) with an estimated temperature of 6250K. We
supplement our sample with SDSS ugriz photometry for a fraction of the
newly identified white dwarfs. A kinematical study of this sample of
white dwarfs, characterized by proper motions ranging from 0.136"/yr
to 0.611"/yr, suggest that they belong to the thin disk population.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 83 61 NLTT white dwarfs
table2.dat 62 25 SDSS Colors of NLTT White Dwarfs
table3.dat 93 61 White Dwarf Parameters and Kinematics
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See also:
I/98 : NLTT Catalogue (Luyten, 1979)
J/ApJ/582/1011 : Revised NLTT Catalog (Salim+, 2003)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 5 I5 ---- NLTT NLTT number
7- 35 A29 --- OName Other name(s)
37- 41 F5.3 arcsec/yr pm Total proper motion (1)
43- 47 F5.1 deg pmPA Position angle of proper motion (1)
49- 53 F5.2 mag Vmag V magnitude
55- 58 F4.2 mag e_Vmag rms uncertainty on Vmag
59 A1 --- r_Vmag [a-f] Vmag reference (2)
61- 65 F5.2 mag V-J V-J colour index (3)
67- 70 F4.2 mag e_V-J rms uncertainty on V-J
72- 77 F6.3 mag J-H J-H colour index (3)
79- 83 F5.3 mag e_J-H rms uncertainty on J-H
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Note (1): From Salim & Gould, Cat. J/ApJ/582/1011
Note (2): References as follows:
a = From Salim & Gould (2003, Cat. J/ApJ/582/1011)
c = From SPM Catalog 2.0. (1998, Cat. I/277
d = From Kilkenny et al. (1997, Cat. J/MNRAS/287/867)
e = From Eggen (1968ApJS...16...97E 1968ApJS...16...97E)
f = From Beers et al. (1992, Cat. J/AJ/103/267)
Note (3): from 2MASS magnitudes converted to CIT.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- NLTT NLTT number
7- 25 A19 --- SDSS SDSS name (JHHMMSS.ss+DDMMSS.s)
27- 31 F5.3 mag u-g SDSS u-g colour index
33- 37 F5.3 mag e_u-g rms uncertainty on u-g
39- 43 F5.3 mag g-r SDSS g-r colour index
45- 49 F5.3 mag e_g-r rms uncertainty on g-r
51- 56 F6.3 mag r-i SDSS r-i colour index
58- 62 F5.3 mag e_r-i rms uncertainty on r-i
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 5 I5 ---- NLTT NLTT number
7- 13 A7 --- Obs Observatories
15- 22 A8 --- WD Other name(s)
23- 25 A3 --- n_WD [abe, ] Note (1)
27- 29 A3 --- SpT Spectral type
31 A1 --- l_Teff [~] Limit flag on Teff
32- 36 I5 K Teff Effective temperature
38- 41 I4 K E_Teff ? Error on Teff (upper limit)
43- 46 I4 K e_Teff ? Error on Teff (lower limit)
47 A1 --- n_Teff [c] Note (1)
49- 52 F4.2 [cm/s2] logg ? Surface gravity
54- 57 F4.2 [cm/s2] e_logg ? rms uncertainty on logg
58 A1 --- n_logg [M] M for Magnetic
59 A1 --- u_logg [)] uncertainty flag on logg
61- 64 F4.2 solMass Mass Mass
66- 69 F4.2 solMass e_Mass ? rms uncertainty on Mass
70 A1 --- u_Mass [)] uncertainty flag on Mass
72 A1 --- l_VMAG [~] Limit flag on VMAG
73- 77 F5.2 mag VMAG Absolute V magnitude
78 A1 --- n_VMAG [d] d: see text for new cool DQ white dwarf
NLTT 31347
80- 81 I2 pc Dist Heliocentric estimated distance
83- 85 I3 km/s UVel U space velocity
87- 89 I3 km/s VVel V space velocity
91- 93 I3 km/s WVel W space velocity
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Note (1): Note as follows:
a = Also in Kawka et al. (2004AJ....127.1702K 2004AJ....127.1702K)
b = Also in Vennes & Kawka (2003ApJ...586L..95V 2003ApJ...586L..95V)
c = Possible binary, Teff estimate from V-J,J-H diagram
e = Double degenerate system.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 25-Sep-2008