J/A+A/423/755 Color-Induced Displacement double stars in SDSS (Pourbaix+, 2004)
Color-Induced Displacement double stars in SDSS.
Pourbaix D., Ivezic Z., Knapp G.R., Gunn J.E., Lupton R.H.
<Astron. Astrophys. 423, 755 (2004)>
=2004A&A...423..755P 2004A&A...423..755P
ADC_Keywords: Surveys ; Stars, double and multiple ; Photometry, SDSS
Keywords: astrometry - stars: binaries: general
Abstract:
We report the first successful application of the astrometric
color-induced displacement technique (CID, the displacement of the
photocenter between different band-passes dur to a varying
contribution of differently colored components to the total light),
originally proposed by Wielen (1996A&A...314..679W 1996A&A...314..679W) for discovering
unresolved binary stars.
Description:
Table 1 contains the 346 objects from the SDSS data release 2
(http://www.sdss.org/dr2) that exhibit a displacement of the
photocenter between that measured in the u and z bands. Such a
displacement is attributed to the binary nature of the object. Besides
the equatorial positions, the table contains the magnitudes and
uncertainties measured in the five photometric filters (u,g,r,i,z) and
the respective offsets in right ascension and declinations. By
construction, the offsets in the r bands are null and were therefore
omitted.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 213 346 Objects from SDSS Data Release 2 that exhibit a
displacement of the photocenter between that
measured in the u and z bands.
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See also:
http://www.sdss.org/dr2 : SDSS Data Release 2 Home Page
J/AJ/126/2579 : SDSS quasar catalog. II. First data release (Schneider+, 2003)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 16 F16.12 deg RAdeg Right ascension (in decimal degree) (J2000)
18- 33 F16.12 deg DEdeg Declination (in decimal degree) (J2000)
35- 42 F8.5 mag umag u magnitude
44- 51 F8.5 mag gmag g magnitude
53- 60 F8.5 mag rmag r magnitude
62- 69 F8.5 mag imag i magnitude
71- 78 F8.5 mag zmag z magnitude
80- 89 F10.8 mag e_umag Uncertainty on the u magnitude
91-100 F10.8 mag e_gmag Uncertainty on the g magnitude
102-111 F10.8 mag e_rmag Uncertainty on the r magnitude
113-122 F10.8 mag e_imag Uncertainty on the i magnitude
124-133 F10.8 mag e_zmag Uncertainty on the z magnitude
135-143 F9.6 arcsec oRAu Offset in right ascension in the u band
145-153 F9.6 arcsec oRAg Offset in right ascension in the g band
155-163 F9.6 arcsec oRAi Offset in right ascension in the i band
165-173 F9.6 arcsec oRAz Offset in right ascension in the z band
175-183 F9.6 arcsec oDEu Offset in declination in the u band
185-193 F9.6 arcsec oDEg Offset in declination in the g band
195-203 F9.6 arcsec oDEi Offset in declination in the i band
205-213 F9.6 arcsec oDEz Offset in declination in the z band
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Acknowledgements: Dimitri Pourbaix
(End) Patricia Vannier [CDS] 18-May-2004