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J/AJ/125/1711       Broad Absorption Line Quasars from SDSS   (Reichard+, 2003)

A catalog of Broad Absorption Line Quasars from the Sloan Digital Sky Survey Early Data Release. Reichard T.A., Richards G.T., Schneider D.P., Hall P.B., Tolea A., Krolik J.H., Tsvetanov Z., Vanden Berk D.E., York D.G., Knapp G.R., Gunn J.E., Brinkmann J. <Astron. J. 125, 1711 (2003)> =2003AJ....125.1711R
ADC_Keywords: QSOs ; Redshifts ; Photometry, SDSS Keywords: quasars: absorption lines - quasars: general Abstract: We present a catalog of 224 broad absorption line quasars (BALQSOs) from the Sloan Digital Sky Survey's Early Data Release Quasar Catalog, (Schneider et al., 2002, Cat. J/AJ/123/567) including a relatively complete and homogeneous subsample of 131 BALQSOs. Since the identification of BALQSOs is subject to considerable systematic uncertainties, we attempt to create a complete sample of SDSS BALQSOs by combining the results of two automated selection algorithms and a by-eye classification scheme. One of these automated algorithms finds broad absorption line troughs by comparing with a composite quasar spectrum. We present the details of this algorithm and compare this method with one that uses a power-law fit to the continuum. The BALQSOs in our sample are further classified as high-ionization BALQSOs (HiBALs), low-ionization BALQSOs (LoBALs), and BALQSOs with excited iron absorption features (FeLoBALs); composite spectra of each type are presented. We further present a study of the properties of the BALQSOs in terms of the balnicity distribution, which rises with decreasing balnicity. This distribution of balnicities suggests that the fraction of quasars with intrinsic outflows may be significantly underestimated. The balnicity index defined by Weymann et al. (1991ApJ...373...23W) amounts to a sort of equivalent width: a quasar is declared to be a BAL when its balnicity index is ≥0. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 100 185 SDSS EDR BALQSO Catalog: Objects with 1.7≤z≤4.2 table2.dat 99 39 Supplementary SDSS EDR BALQSO Catalog
See also: J/AJ/123/567 : SDSS quasar catalog (Schneider+, 2002) Byte-by-byte Description of file: table1.dat table2.dat
Bytes Format Units Label Explanations
1- 18 A18 --- SDSS SDSS object name (1) 20- 22 I3 --- PNum Plate number 24- 26 I3 --- FNum Fiber number 28- 32 I5 d MJD Modified Julian Date of observation 34 I1 --- Final [0/1] Final quasar target candidate (2) 36 I1 --- EDR [0/1] Early Data Release quasar target candidate (2) 38 I1 --- Ser [0/1] Early Data Release serendipity target candidate (2) 40- 44 F5.2 mJy 20cm ? FIRST peak flux density at 20cm (3) 46- 50 F5.3 --- z Redshift 52- 56 F5.2 mag i*mag Apparent i*-band magnitude (4) 58- 63 F6.2 mag i*Mag Resulting absolute i*-band magnitude 65- 69 I5 km/s CIV1 ? C IV balnicity index (5) 71- 75 I5 km/s CIV2 ? C IV balnicity index from Tolea et al., 2002ApJ...578L..31T (6) 77- 80 I4 km/s MgII ? Mg II balnicity index (5) 82 A1 --- C1 [HN] Fitted composite algorithm classification (7) 84 A1 --- C2 [HN] The Tolea et al., 2002ApJ...578L..31T classification (7) 86- 91 A6 --- C3 Visual classification (8) 93- 96 A4 --- C4 Overall classification (9) 98- 99 A2 --- Notes Additional notes (10)
Note (1): Using the SDSS format of J2000 right ascension (hhmmss.ss) and declination (±ddmmss.s). The "J" prefix should be added. Note (2): Final quasar target candidate: 1 = Selected; 0 = Not selected. Note (3): Null value indicates that the object is undetected in the FIRST survey at the ∼1mJy limit. Note (4): Corrected for Galactic reddening using Schlegel, Finkbeiner, & Davis, 1998ApJ...500..525S. Note (5): Computed using a fitted EDR composite spectrum as the continuum. Note (6): Computed using a power law with Gaussian C IV emission line as the continuum. Note (7): Classification: H = HiBAL; N = Non-BALQSO. Note (8): A question mark means uncertainty in the previous code; e.g., ``HiLo?'' means a tentative LoBAL through in a definite HiBAL. HiZ = HiBAL at z≥3.90, where LoBALs could be missed because λAlIII>9150Å; Hiz/Loz = Hi/LoBAL at z≥2.26, where LoBALs could be missed because λMgII>9150Å; Hi = Only high-ionization lines are present; Lo = Both high- and low-ionization lines are present; LoZ = LoBAL at z≥3.90, where LoBALs could be missed because λAlIII>9150Å; FeLo = High-, low-, and metastable Fe II/Fe III lines (∼2600Å, or otherwise) or atypical absorption that more readily classifies the object as an unusual or extreme BALQSO, usually with strong iron absorption; no = No broad absorption lines are present (non-BAL). Note (9): Overall classification: Lo = LoBAL if visual inspection classified the object as a LoBAL; FeLo = Visual inspection also revealed a few unusual LoBALs with iron absorption (FeLoBALs); Hi = The remaining objects are those classified as HiBALs by at least one of the three classification methods. Note (10): Additional notes: e: The balnicity indexes of these objects are formally zero (or unmeasured), but visual inspection suggests that the objects belong in this table. For SDSS 0149-0114 and SDSS 1132+0104 a small change in redshift would yield a positive BI. In the case of SDSS 1730+5850, Hall et al., 2002ApJS..141..267H found a BI greater than 10,900. f: See also Hall et al., 2002ApJS..141..267H; g: See also Menou et al., 2001ApJ...561..645M; h: This quasar was selected for spectroscopic follow-up as a star; i: This quasar was selected for spectroscopic follow-up as a galaxy.
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 13-May-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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