J/A+A/486/843 White dwarf-red dwarf binaries in the SDSS (Augusteijn+, 2008)
White dwarf-red dwarf binaries in the SDSS. I. Sample definition.
Augusteijn, T., Greimel R., van den Besselaar E.J.M., Groot P.J.,
Morales-Rueda L.
<Astron. Astrophys. 486, 843 (2008)>
=2008A&A...486..843A 2008A&A...486..843A
ADC_Keywords: Binaries, spectroscopic ; Photometry, SDSS
Keywords: binaries: spectroscopic - stars: late-type - white dwarfs
Abstract:
To reduce contamination by more distant sources, such as quasars, we
have selected candidate white dwarf-red dwarf binaries from the
catalogue of proper motion stars drawn from the intersection of the
Sloan Digital Sky Survey (SDSS) and the USNO-B1.0 catalogue.
Description:
To separate single from binary sources and to cut spurious sources
out, we defined selection criteria based on a combination of the
(u-g), (g-r), and (r-i) colours. Here we list the final sample of 651
binary candidates. We found that for r magnitudes brighter than ∼16.5
the proper motion catalogue is heavily contaminated with sources that
have incorrect colours due to the r magnitudes being relatively too
faint, most likely due to saturation effects. The level of
contamination can be reduced by either excluding sources brighter than
r=16.5mag or by excluding sources bluer than (u-g)=-0.5 or (g-r)=-0.6
and brighter than r=16.0mag.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
sample.dat 66 651 The final sample of binary candidates
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See also:
J/ApJS/152/103 : Proper-motion catalog SDSS + USNO-B (Gould+, 2004)
http://www.sdss.org : SDSS Home Page
Byte-by-byte Description of file: sample.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [SDSS]
6- 24 A19 --- SDSS SDSS designation (JHHMMSS.ss+DDMMSS.s)
26- 31 F6.1 mas/yr pm Proper motion
33- 38 F6.3 mag rmag SDSS r magnitude
40- 45 F6.3 mag u-g SDSS u-g colour index
47- 52 F6.3 mag g-r SDSS g-r colour index
54- 59 F6.3 mag r-i SDSS r-i colour index
61- 66 F6.3 mag i-z SDSS i-z colour index
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Acknowledgements:
Thomas Augusteijn, tau(at)not.iac.es
(End) Thomas Augusteijn [NOT], Patricia Vannier [CDS] 25-Jan-2008