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J/ApJ/699/782        High-redshift SDSS-DR5 QSOs         (Diamond-Stanic+, 2009)

High-redshift SDSS quasars with weak emission lines. Diamond-Stanic A.M., Fan X., Brandt W.N., Shemmer O., Strauss M.A., Anderson S.F., Carilli C.L., Gibson R.R., Jiang L., Kim J.S., Richards G.T., Schmidt G.D., Schneider D.P., Shen Y., Smith P.S., Vestergaard M., Young J.E. <Astrophys. J., 699, 782-799 (2009)> =2009ApJ...699..782D
ADC_Keywords: QSOs ; Equivalent widths ; Redshifts Keywords: quasars: emission lines - quasars: general Abstract: We identify a sample of 74 high-redshift quasars (z>3) with weak UV emission lines from the Fifth Data Release of the Sloan Digital Sky Survey and present infrared, optical, and radio observations of a subsample of four objects at z>4. These weak emission-line quasars (WLQs) constitute a prominent tail of the Lyα+NV equivalent width distribution, and we compare them to quasars with more typical emission-line properties and to low-redshift active galactic nuclei with weak/absent emission lines, namely BL Lac objects. We find that WLQs exhibit hot (T∼1000K) thermal dust emission and have rest-frame 0.1-5um spectral energy distributions that are quite similar to those of normal quasars. The variability, polarization, and radio properties of WLQs are also different from those of BL Lacs, making continuum boosting by a relativistic jet an unlikely physical interpretation. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 66 5374 Parameters for all z>3 quasars
See also: VII/260 : The SDSS-DR7 quasar catalog (Schneider+, 2010) J/ApJ/692/758 : BAL QSOs in SDSS-DR5 (Gibson+, 2009) J/MNRAS/399/2231 : SDSS DR5 BALQSO catalog (Scaringi+, 2009) J/MNRAS/391/369 : New z≥3.6 QSOs from FIRST-SDSS DR5 (Carballo+, 2008) J/ApJS/165/1 : BAL QSOs from SDSS DR3 (Trump+, 2006) J/MNRAS/370/1034 : FIRST-APM-SDSS survey for high-z radio QSOs (Carballo+, 2006) J/AJ/121/31 : High-redshift quasars in SDSS (Fan+, 2001) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 18 A18 --- SDSS Quasar SDSS identification ( 19- 21 A3 --- n_SDSS [sdw, ] quasar belongs to sample(s) (1) 23- 27 F5.1 0.1nm EW1 ? Lyα+NV equivalent width in Angstroms 29- 32 F4.1 0.1nm e_EW1 ? The 1σ error in EW1 34- 38 F5.1 0.1nm EW2 ? CIV equivalent width in Angstroms 40- 44 F5.1 0.1nm e_EW2 ? The 1σ error in EW2 46- 50 F5.2 --- alpha Spectral index α (fν∝να) 52- 55 F4.2 --- z SDSS-DR5 redshift 57 A1 --- l_R Limit flag on R 58- 62 I5 --- R ? The radio-loudness R parameter (2) 64 I1 --- Sel Uniform selection flag (3) 66 I1 --- BAL BAL flag (4)
Note (1): Flag as follows: s = Included in the subsample of for objects at z>4 (additional data in tables 3-8 of the paper) w = Included in the sample of the 74 weak emission-line quasars. See section 2 for further details. d = Included in the sample of weak emission-line quasars and EW(CIV)>10Å. Note (2): The radio-loudness parameter R, is defined as the ratio of radio to optical flux density. We adopt the definition used by Jiang et al. (2007ApJ...656..680J), where R=fν(6cm)/fν(2500Å). The upper limits use the FIRST catalog detection limit, a 5σ threshold that includes CLEAN bias. Note (3): In Fifth Data Release Quasar Catalog; flag as follows: 0 = not selected as a primary quasar target by the final target selection algorithm given by Richards et al. (2002AJ....123.2945R); 1 = selected as a primary quasar target by the final target selection algorithm. Note (4): BAL flag as follows: 0 = not identified as a BAL in either Trump et al. (2006, Cat. J/ApJS/165/1) or Gibson et al. (2009, Cat. J/ApJ/692/758) catalog 1 = identified as a BAL in Trump et al. (2006, Cat. J/ApJS/165/1) catalog only; 2 = identified as a BAL in Gibson et al. (2009, Cat. J/ApJ/692/758) catalog only; 3 = identified as a BAL in both Trump et al. (2006, Cat. J/ApJS/165/1) and Gibson et al. (2009, Cat. J/ApJ/692/758) catalogs.
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 05-Jul-2011
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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