A Wide-field Multicolor Survey for High-Redshift Quasars, z equal to or greater than 2.2 (Warren, S. J., Hewett, P. C., and Osmer, P. S.) Documentation for the Computer-Readable Version Nancy G. Roman Doc. No. NSSDC/WDC-A-R&S 92-09 November 1992 National Space Science Data Center (NSSDC)/ World Data Center A for Rockets and Satellites (WDC-A-R&S) National Aeronautics and Space Administration Goddard Space Flight Center Greenbelt, Maryland 20771 Abstract In a wide-field multicolor survey (45.7 sq. deg. width m(or) between 16.0 and 20.0) the authors discovered 130 new quasars, of which 100 are of redshift z equal to or greater than 2.2. There are 49 new quasars of redshift z equal to or greater than 3.0 including three of z equal to or greater than 4.0. The catalog provides spectra, coordinates, redshifts, broad-band magnitudes (u, b(j), v, or, r, i), line-equivalent widths for Lyman alpha/NV and CIV, and continuum spectral indices. 1 Introduction and Source Reference 1.1 Introduction The goal of the wide-field multicolor survey for high-redshift (that is z equal to or greater than 2.2) quasars is to constrain the quasar luminosity function and its evolution over the redshift interval z between 2.2 and 4.5. The survey is based on the identification of stellar objects with colors different from those of common galactic stars, but redder in (U-B) than most low-redshift quasars. The raw data come from scans by the Automated Plate Measuring facility (APM) of pairs of United Kingdom Schmidt Telescope (UKST) direct plates in six passbands, u, b(j), v, or, r, i. The lowercase letters denote the natural photometric system defined by the UKST emulsion/filter combinations. The survey covers two fields, the south Galactic pole (SPG) at 0h53m -28 03' (1950.0) and UKST field F401 at 20h48m -35 03', for a total effective area 45.7 of square degrees. The respective magnitude ranges are m(or) between 16.00 and 20.00 and between 16.00 and 19.82. Ninety-three new non-UVX quasars were discovered in the SGP field and 37 in F401. The catalog lists the details of these new quasars in right ascension order. The coordinates are accurate to about 1". Finding charts can be made available on request to Hewett. Three of the new SGP quasars were discovered independently by others. The equivalent widths (EWs) were measured in all cases where the complete line was included in the spectrum. This is also the case for the full width, half maximum (FWHM) C IV except that that quantity was not measured for the broad absorption-line (BAL) quasars. The measurement of the spectral index was limited to objects of redshift z equal to or greater than 2.2. The published paper contains the spectra. 1 Candidates for the catalog were selected by identifying outliers from the stellar sequence that exists in the six-dimensional parameter space defined by the six broad-band magnitudes. Lists of about 1000 candidates in each field (List A) that are redder than a specified limit m(u) - m(j) (the non-ultraviolet excess) were compiled. Following an exploration of the contents of these lists, the sample was restricted, using precisely-defined criteria (List B), to objects farthest from the mean line, as well as candidates further down the lists that possess similar colors to the high-redshift quasars already discovered. 1.2 Source Reference "A Wide-Field Multicolor Survey for High-Redshift Quasars, z equal to or greater than 2.2. II. The Quasar Catalog" 1991, Warren, S. J., Hewitt, P. C., and Osmer, P. S., ApJS, 76, 23 2 Structure 2.1 File Structure The "A Wide-Field Survey for High-Redshift Quasars, z equal to or greater than 2.2 II. The Quasar Catalog" as distributed here is in a single fixed block file. It contains 130 records, each 129 bytes long. The four tables in the printed paper have been concatenated into one with the SGP field first, followed by F401 and all data for each quasar on a single line. This information is sufficient for a user to describe the indigenous characteristics of the machine-readable version of the "A Wide-Field Survey for High-Redshift Quasars, z equal to or greater than 2.2 II. The Quasar Catalog" to a computer. A copy of this document should accompany any further distribution of this file. 2.2 File Format Table 1 gives a byte-by-byte description of the contents of the data file. 2 Bytes Unit Format Item 2 - 9 A8 Number 12 - 13 deg I2 RA(1950) 15 - 16 min I2 RA 18 - 22 sec F5.2 RA 24 - 26 deg I3 Dec(1950) 28 - 29 ' I2 Dec 31 - 34 " F4.2 Dec 36 - 39 year I4 Date of observation 41 - 43 month A3 Date of observation 45 - 46 day I2 Date of observation 48 A1 Telescope 50 - 53 F4.2 z 54 A1 Uncertainty code for z 56 A1 List A 60 A1 List B 63 - 65 A3 Plot no. 67 - 72 mag A6 m(u) 74 - 79 mag A6 m(bj) 81 - 86 mag A6 m(v) 88 - 92 mag F5.2 m(or) 94 - 98 mag F5.2 m(r) 100-105 mag A6 m(i) 107-110 A A4 Eq. width Ly alpha/NV 112-117 A A6 Eq. width CIV 119-121 A A3 FWHM CIV 124-129 A5 Spectral index Table 1: Format 3 Notes to the Catalog Telescope: A = AAT, C = CTIO 4 m. 0043-296 is also in Boyle et al. 1990 and Anderson et al. 1991. 0049-286 and 0052-297 are also in Anderson et al. 1991. The redshift of 0043-275 is incorrectly stated in Warren et al. 1987a. 0100-283A is classified as marginally non-stellar. 0100-292 is fainter than the sample limit. When two values are given for the equivalent width, they are BAL emission/absorption EW. 3 The spectral index for 0101-304 is taken from Schneider, Schmidt, & Gunn 1989. The spectral indices for the objects in field F401 have been dereddened. 4 Acknowledgments We thank Dr. Warren for forwarding to us a machine-readable version of the catalog. 5 References "A Wide-Field Multicolor Survey for High-Redshift Quasars, z equal to or greater than 2.2 II. The Quasar Catalog" Warren, S. J., Hewitt, P. C., and Osmer, P. S., 1991, ApJS, 76, 23 4