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J/ApJ/663/1291      DZ stars in SDSS DR4                     (Dufour+, 2007)

On the spectral evolution of cool, helium-atmosphere white dwarfs: detailed spectroscopic and photometric analysis of DZ stars. Dufour P., Bergeron P., Liebert J., Harris H.C., Knapp G.R., Anderson S.F., Hall P.B., Strauss M.A., Collinge M.J., Edwards M.C. <Astrophys. J., 663, 1291-1308 (2007)> =2007ApJ...663.1291D
ADC_Keywords: Stars, white dwarf ; Effective temperatures ; Abundances Keywords: stars: abundances - stars: atmospheres - stars: evolution - white dwarfs Abstract: We present a detailed analysis of a large spectroscopic and photometric sample of DZ white dwarfs based on our latest model atmosphere calculations. We revise the atmospheric parameters of the trigonometric parallax sample of Bergeron, Leggett, & Ruiz (2001, Cat. J/ApJS/133/413, 12 stars) and analyze 147 new DZ white dwarfs discovered in the SDSS. The inclusion of metals and hydrogen in our model atmosphere calculations leads to different atmospheric parameters than those derived from pure helium models. Description: The first sample used for this study is drawn from the Bergeron et al. (1997ApJS..108..339B, BRL97) and (2001, Cat. J/ApJS/133/413, BLR01) analyses, which include 12 DZ stars with optical BVRI and infrared JHK photometry, as well as trigonometric parallax measurements, with the exception of ESO 445-271 (WD 1338-311), for which the parallax and JHK measurements are not available. Our second sample consists of DZ white dwarfs spectroscopically identified in the SDSS. We selected all DZ stars from the First and Fourth Data Release white dwarf catalogs (Kleinman et al. 2004, Cat. J/ApJ/607/426 and Eisenstein et al. 2006, Cat. J/ApJS/167/40). File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 78 147 Atmospheric parameters of DZ Stars from the SDSS
See also: J/ApJ/607/426 : Catalog of white dwarfs in SDSS-DR1 (Kleinman+, 2004) J/ApJS/167/40 : SDSS4 confirmed white dwarfs catalog (Eisenstein+, 2006) Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 4 A4 --- --- [SDSS] 6- 24 A19 --- SDSS SDSS designation ( 26- 29 I4 --- Plate SDSS plate number 31- 35 I5 --- MJD SDSS MJD number 37- 39 I3 --- Fiber SDSS Fiber number 41- 45 I5 K Teff Effective temperature 47- 49 I3 K e_Teff rms uncertainty on Teff 51- 56 F6.2 [-] log(Ca/He) Ca/He abundance 58- 61 F4.2 [-] e_log(Ca/He) rms uncertainty on log(Ca/He) 63- 65 I3 pc Dist Heliocentric distance 67 A1 --- l_log(H/He) Limit flag on log(H/He) 68- 72 F5.2 [-] log(H/He) H/He abundance 74- 77 F4.2 [-] e_log(H/He) ? rms uncertainty on log(H/He) 78 A1 --- R [*] indicates the SDSS name was corrected at CDS (see the "History" section below)
History: * 19-Aug-2009: From electronic version of the journal * 20-Jan-2010: 4 errors detected in the sign of the SDSS designation and fixed at CDS; these records are marked by an asterisk (*) in the additional column "R" of the table (Fabienne Woelfel, CDS)
(End) Patricia Vannier [CDS] 19-Aug-2009
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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