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Spectroscopic CCD surveys for quasars at large redshift. 3: The Palomar Transit Grism Survey catalogThis paper reports the initial results of the Palomar Transit Grism Survey (PTGS). The PTGS was designed to produce a sample of z greater than 2.7 quasars that were identified by well-defined selection criteria. The survey consists of six narrow (approximately equal to 8.5 min wide) strips of sky; the total effective area is 61.47 sq deg. Low-resolution slitless spectra, covering the wavelength range from 4400 to 7500 A, were obtained for approximately 600 000 objects. The wavelength- and flux-calibrated spectra were searched for emission lines with an automatic software algorithm. A total to 1655 emission features in the grism data satisfied our signal-to-noise ratio and equivalent width selection criteria; subsequent slit spectroscopy of the candidates confirmed the existence of 1052 lines (928 different objects). Six groups of emission lines were detected in the survey: Lyman alpha + N V, C IV, C III1, Mg II, H Beta + (O III), and H alpha + (S II). More than two-thirds of the candidates are low-redshift (z less than 0.45) emission-line galaxies; ninety objects are high-redshift quasars (z greater than 2.7) detected via their Lyman alpha + N V emission lines. The survey contains three previously unknown quasars brighter than 17th magnitude; all three have redshifts of approximately equal to 1.3. In this paper we present the observational properties of the survey, the algorithms used to select the emission-line candidates, and the catalog of emission-line objects.
Document ID
19950030800
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Schneider, Donald P.
(Institute for Advanced Study, Princeton, NJ United States)
Schmidt, Maarten
(California Inst. of Tech., Pasadena, CA United States)
Gunn, James E.
(Princeton Univ. Observatory, Princeton, NJ, United States)
Date Acquired
August 16, 2013
Publication Date
April 1, 1994
Publication Information
Publication: The Astronomical Journal
Volume: 107
Issue: 4
ISSN: 0004-6256
Subject Category
Astronomy
Accession Number
95A62399
Funding Number(s)
CONTRACT_GRANT: NAG5-1618
CONTRACT_GRANT: NSF AST-91-08834
CONTRACT_GRANT: NSF AST-86-18257A02
CONTRACT_GRANT: NSF AST-87-15508
Distribution Limits
Public
Copyright
Other

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