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J/A+A/399/469     Parkes Quarter-Jansky Flat-Spectrum Sample. II. (Hook+, 2003)

The Parkes Quarter-Jansky Flat-Spectrum Sample. 2. New optical spectra and redshift measurements. Hook I.M., Shaver P.A., Jackson C.A., Wall J.V., Kellermann K.I. <Astron. Astrophys. 399, 469 (2003)> =2003A&A...399..469H
ADC_Keywords: QSOs ; Redshifts Keywords: quasars: general Abstract: We present optical spectra and redshift measurements for 178 flat-spectrum objects from the Parkes quarter-Jansky flat-spectrum sample. These spectra were obtained in order to compile a complete sample of quasars for use in a study of quasar evolution. We present a composite optical spectrum made from the subset of 109 quasars that have flux densities in the range 0.25Jy<S(2.7GHz)<0.5Jy, and make a comparison with a composite spectrum for radio-quiet QSOs from the Large Bright Quasar Survey. Our large sample of radio-loud quasars allows us to strengthen previous reports that the Ly and CIV emission lines have larger equivalent width in radio-loud quasars than radio-quiet QSOs to greater than the 3σ level. However we see no significant difference in the equivalent widths of CIII] or MgII. We also show that the flux decrements across the Lyman-α line (DA) measured from these spectra show the same trend with redshift as for optically selected QSOs. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file tablea1.dat 31 178 Redshifts for the Parkes quarter-Jansky flat-spectrum sample notes.dat 80 28 Individual notes
See also: VIII/34 : Parkes Half-Jansky Flat-Spectrum Sample (Drinkwater + 1997) J/A+A/386/97 : Parkes Quarter-Jansky Flat-Spectrum Sample. I. (Jackson+, 2002) Byte-by-byte Description of file: tablea1.dat
Bytes Format Units Label Explanations
1- 9 A9 --- Name QSO name (BHHMM-DDd) 10 A1 --- n_Name [*] for a note detailed in notes.dat file 12- 16 F5.3 --- z ? Redshift 18 I1 --- Conf [0/2] Level of confidence of the redshift (1) 20- 22 A3 --- Class Classification, reproduced from Jackson et al. (2002, Cat. J/A+A/386/97) (2) 24- 30 A7 "MM/YYYY" Date Observation date
Note (1): Level of confidence in the redshift 0 = no lines for redshift determination 1 = secure redshift 2 = single line or weak lines Note (2): These classifications are based on both the spectrum and images of the source and their meanings are as follows: Q = confirmed quasar by spectroscopy or UVX photometry BL = spectroscopically-confirmed BL Lac object G = Galaxy with morphological or spectroscopic confirmation NCS = Non-compact radio source (the source is either a steep-spectrum or extended radio source)
Byte-by-byte Description of file: notes.dat
Bytes Format Units Label Explanations
1- 9 A9 --- Name Name 11- 80 A70 --- Note Text of the note
History: From electronic version of the journal
(End) Patricia Bauer [CDS] 11-Feb-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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