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J/AJ/126/1023       White Dwarfs in the SDSS                 (Harris+, 2003)

An initial survey of white dwarfs in the Sloan Digital Sky Survey. Harris H.C., Liebert J., Kleinman S.J., Nitta A., Anderson S.F., Knapp G.R., Krzesinski J., Schmidt G., STrauss M.A., Vanden Berk D., Eisenstein D., Hawley S., Margon B., Munn J.A., Silvestri N.M., Smith J.A., Szkody P., Collinge M.J., Dahn C.C., Fan X., Hall P.B., Schneider D.P., Brinkmann J., Burles S., Gunn J.E., Hennessy G.S., Hindsley R., Ivezic Z., Kent S., Lamb D.Q., Lupton R.H., Nichol R.C., Pier J.R., Schlegel D.J., Subbarao M., Uomoto A., Yanny B., York D.G. <Astron. J. 126, 1023 (2003)> =2003AJ....126.1023H
ADC_Keywords: Stars, white dwarf Keywords: Stars, dwarfs ; Photometry, SDSS ; Proper motions Abstract: An initial assessment is made of white dwarf and hot subdwarf stars observed in the Sloan Digital Sky Survey. In a small area of sky (190 square degrees), observed much like the full survey will be, 269 white dwarfs (WDs) and 56 hot subdwarfs are identified spectroscopically where only 44 white dwarfs and five hot subdwarfs were known previously. Most are ordinary DA (hydrogen atmosphere) and DB (helium) types. In addition, in the full survey to date, a number of WDs have been found with uncommon spectral types. Among these are blue DQ stars displaying lines of atomic carbon; red DQ stars showing molecular bands of C2 with a wide variety of strengths; DZ stars where Ca and occasionally Mg, Na, and/or Fe lines are detected; and magnetic WDs with a wide range of magnetic field strengths in DA, DB, DQ, and (probably) DZ spectral types. Photometry alone allows identification of stars hotter than 12000K, and the density of these stars for magnitude g 15<g<20 is found to be ∼2.2deg-2 at Galactic latitudes of 29°-62°. Spectra are obtained for roughly half of these hot stars. The spectra show that for 15<g<17, 40% of hot stars are WDs, and the fraction of WDs rises to ∼90% at g=20. The remainder are hot sdB and sdO stars. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 84 249 DA and DB white dwarfs table2.dat 84 69 Unusual white dwarfs table3.dat 84 56 Hot subdwarfs notes.dat 81 46 Notes on tables 1, 2, 3
See also: J/AJ/123/3409 : SDSS M, L, and T dwarfs (Hawley+, 2002) Byte-by-byte Description of file: table*.dat
Bytes Format Units Label Explanations
1- 2 I2 h RAh Hour of right ascension (J2000) (1) 4- 5 I2 min RAm Minute of right ascension (J2000) (1) 7- 11 F5.2 s RAs Second of right ascension (J2000) (1) 13 A1 --- DE- Sign of the declination (J2000) (1) 14- 15 I2 deg DEd Degree of declination (J2000) (1) 17- 18 I2 arcmin DEm Arcminute of declination (J2000) (1) 20- 23 F4.1 arcsec DEs Arcsecond of declination (J2000) (1) 25- 29 F5.2 mag gmag SDSS g-band magnitude 31- 35 F5.2 mag u-g ? The SDSS (u-g) color 37- 41 F5.2 mag g-r The SDSS (g-r) color 43- 47 F5.2 mag r-i The SDSS (r-i) color 49- 53 F5.2 mag i-z The SDSS (i-z) color 55- 58 F4.2 mag Au Full SDSS u-band interstellar absorption (2) 60 A1 --- l_pm [≲] Limit or approximate flag on PM 64- 66 I3 mas/yr pm Total proper motion (3) 68- 70 I3 deg pmPA ? Position angle of the proper motion 72- 78 A7 --- SpType Spectral type (4) 80- 84 A5 --- Note Individual notes, detailed in file notes.dat
Note (1): Object name is "SDSS J+" plus the coordinates. Note (2): From Schlegel et al. (1998ApJ...500..525S). Reddening can be calculated using E(u-g)=0.264Au, E(g-r)=0.202Au, E(r-i)=0.129Au, and E(i-z)=0.119Au. For most stars at these high latitudes, the reddening is small whether or not the full absorption Note (3): Calculated using the USNO-A2.0 catalog (Monet et al., Cat. I/252) for the first-epoch position. For a few stars not in the USNO-A catalog, usually because they are too faint to be detected on both the POSS-I blue and red plates, the first-epoch position is taken from the USNO-B1.0 catalog (Monet et al., 2003, Cat. I/284). The proper motions typically have errors of 6-8mas/yr rms. Where the motion is less than 20mas/yr, it may not be real, and the position angle of the motion is omitted. Note (4): From our classification of the SDSS spectra.
Byte-by-byte Description of file: notes.dat
Bytes Format Units Label Explanations
1- 2 I2 --- Note Note number (1-24 in table 1, 30-47 in table2, 46- 51 in table3) 4 A1 --- --- [=] 6- 81 A76 --- Text Text of the note
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Laurent Cambresy [CDS] 05-Sep-2003
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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