J/ApJS/204/5 SDSS DR7 white dwarf catalog (Kleinman+, 2013)
SDSS DR7 white dwarf catalog.
Kleinman S.J., Kepler S.O., Koester D., Pelisoli I., Pecanha V., Nitta A.,
Costa J.E.S., Krzesinski J., Dufour P., Lachapelle F.-R., Bergeron P.,
Yip C.-W., Harris H.C., Eisenstein D.J., Althaus L., Corsico A.
<Astrophys. J. Suppl. Ser., 204, 5 (2013)>
=2013ApJS..204....5K 2013ApJS..204....5K
ADC_Keywords: Photometry, SDSS ; Stars, white dwarf ; Stars, masses ;
Proper motions ; Surveys ; Spectral types
Keywords: catalogs - magnetic fields - surveys - white dwarfs -
stars: luminosity function, mass function
Abstract:
We present a new catalog of spectroscopically confirmed white dwarf
stars from the Sloan Digital Sky Survey (SDSS) Data Release 7
spectroscopic catalog. We find 20407 white dwarf spectra, representing
19712 stars, and provide atmospheric model fits to 14120 DA and 1011
DB white dwarf spectra from 12843 and 923 stars, respectively. These
numbers represent more than a factor of two increase in the total
number of white dwarf stars from the previous SDSS white dwarf
catalogs based on DR4 data. Our distribution of subtypes varies from
previous catalogs due to our more conservative, manual classifications
of each star in our catalog, supplementing our automatic fits. In
particular, we find a large number of magnetic white dwarf stars whose
small Zeeman splittings mimic increased Stark broadening that would
otherwise result in an overestimated logg if fit as a non-magnetic
white dwarf. We calculate mean DA and DB masses for our clean,
non-magnetic sample and find the DB mean mass is statistically larger
than that for the DAs.
Description:
Here, we report on the white dwarf catalog built from the SDSS DR7
(Cat. II/294). We have applied automated techniques supplemented by
complete, consistent human identifications of each candidate white
dwarf spectrum. We make use of the latest SDSS reductions and white
dwarf model atmosphere improvements in our spectral fits, providing
logg and Teff determinations for each identified clean DA and DB where
we use the word "clean" to identify spectra that show only features of
non-magnetic, nonmixed, DA or DB stars. Our catalog includes all white
dwarf stars from the earlier Kleinman et al. (2004, Cat.
J/ApJ/607/426) and Eisenstein et al. (2006, Cat. J/ApJS/167/40)
catalogs, although occasionally with different identifications.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 361 20407 Catalog of white dwarfs
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See also:
II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)
J/MNRAS/417/1210 : DA-white dwarfs from SDSS and UKIDSS (Girven+, 2011)
J/ApJ/730/128 : Spectroscopy of DA WD from the SDSS-DR4 (Tremblay+, 2011)
J/A+A/466/627 : Parameters of DA white dwarfs in SDSS-DR1 (Hu+, 2007)
J/ApJS/167/40 : SDSS4 confirmed white dwarfs catalog (Eisenstein+, 2006)
J/AJ/132/1221 : VJHK and SDSS photometry of DA white dwarfs (Holberg+, 2006)
J/AJ/132/676 : SDSS hot DB white dwarfs (Eisenstein+, 2006)
J/ApJ/607/426 : Catalog of white dwarfs in SDSS-DR1 (Kleinman+, 2004)
J/AJ/126/1023 : White Dwarfs in the SDSS (Harris+, 2003)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- SDSS SDSS object name (HHMMSS.ss+DDMMSS.s; J2000)
20- 23 I4 --- Plate SDSS plate number
25- 29 I5 d MJD SDSS Modified Julian date
31- 33 I3 --- Fiber SDSS FiberID
35- 46 F12.8 deg RAdeg Right Ascension in decimal degrees (J2000)
48- 59 F12.8 deg DEdeg Declination in decimal degrees (J2000)
61- 69 F9.6 --- SNg [0.4/90] SDSS g-band signal-to-noise ratio
71- 75 F5.2 mag umag SDSS u band PSF magnitude
77- 80 F4.2 mag e_umag Uncertainty in umag
82- 96 I15 --- f_umag ? Photometric flag on umag (1)
98-102 F5.2 mag gmag ?=0 SDSS g band PSF magnitude
104-108 F5.2 mag e_gmag ?=0 Uncertainty in gmag
110-124 I15 --- f_gmag ? Photometric flag on gmag (1)
126-130 F5.2 mag rmag SDSS r band PSF magnitude
132-135 F4.2 mag e_rmag Uncertainty in rmag
137-151 I15 --- f_rmag ? Photometric flag on rmag (1)
153-157 F5.2 mag imag SDSS i band PSF magnitude
159-164 F6.2 mag e_imag Uncertainty in imag
166-180 I15 --- f_imag ? Photometric flag on imag (1)
182-186 F5.2 mag zmag SDSS z band PSF magnitude
188-192 F5.2 mag e_zmag Uncertainty in zmag
194-208 I15 --- f_zmag ? Photometric flag on zmag (1)
210-219 F10.6 10mas/yr pm SDSS proper motion (arcsec/century)
221-230 F10.6 deg pmPA [0/360[ SDSS proper motion angle; North
through East
232 I1 --- f_pm [1]? SDSS proper motion match
(1=sucessful match within 1.0")
237-244 F8.6 mag Ag [0/4.52885] SDSS g band extinction
246-271 A26 --- GMT GMT observation data/time (when row 0 of r
measurement read)
273-286 A14 --- Atype Spectrum autofit code (2)
288-293 I6 K Teff ? autofit effective temperature (3)
295-299 I5 K e_Teff ? Uncertainty in Teff (3)
301-305 F5.2 [cm/s2] log(g) [5/10]? autofit log surface gravity (3)
307-312 F6.3 [cm/s2] e_log(g) ? Uncertainty in log(g) (3)
314-319 F6.3 --- chi2 [0.28/64.71]? autofit χ2 fit measurement
321-324 A4 --- m_Nsp "dup-" for duplicate spectra or "uniq"
325-328 I04 --- Nsp [0003-2635]? Running number of spectrum
for one object (when duplicate spectra)
329 A1 --- q_Nsp [a] a=best signal to noise ratio (for
duplicate spectra)
331-335 F5.3 Msun Mass [0.06/1.753]? Calculated mass (for clean DAs
and DBs only)
337-341 F5.3 Msun e_Mass [0/0.494]? Uncertainty in Mass
343-361 A19 --- Type Human spectral type assigned to this spectrum
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Note (1): The photometric flag values are processed versions of the flagsband
parameter in the SDSS database. It has been mathematically anded
with the appropriate values to highlight objects that have the
following quality control flags set: EDGE, PEAKCENTER, NOPROFILE,
BADCOUNTSERROR, INTERP_CENTER, DEBLEND_NOPEAK, PSFFLUXINTERP,
SATURATED, and NOTCHECKED. If the value is non-zero, then the
corresponding SDSS magnitude is suspect.
Note (2): Autofit code described in Kleinman et al. (2004, Cat. J/ApJ/607/426)
and Eisenstein et al. (2006, Cat. J/ApJS/167/40):
"DA" (H-lines) or "DB" (He-lines) followed by the θ temperature
subtype (50400K/Teff) and the log(g)s, separated by an underscore. The
CH: prefix and colon suffix are quality assessment checks
Note (3): A blank value indicates an unsuccessful autofit fit. Note that
these parameters are only meaningful for objects identified as a clean
DA or DB. Values for other identifications are provided only as a
diagnostic; they do not represent an attempt to accurately determine
each star's temperature and log(g).
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 28-Jan-2013