Spectroscopic CCD Surveys for Quasars at Large Redshift. V. The Palomar Scan GRISM Survey Catalog

This paper presents the catalog of objects found in the Palomar Scan Grism Survey (PSGS). The survey consists of eight narrow (~8.5‧ wide) strips of sky; the total effective area is 1.10 deg^2. Low-resolution slitless spectra, covering the wavelength range 4400-7500 Å, were obtained for approximately 97,000 objects. The wavelength- and flux-calibrated spectra were searched for emission lines with an automatic software algorithm. A total of 192 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 111 lines (96 different objects). Six groups of emission lines were detected in the survey: Lyalpha + N V, C IV, C III], Mg II, Hβ + [O III], and Hα + [S II]. Slightly more than half of the confirmed lines are low-redshift (z<0.45) emission-line galaxies; nine objects are high-redshift quasars (z>2.7) detected via their Lyalpha + N V emission lines. Two unusual emission-line objects were found as part of the survey; one is a late-type star (M9.5) with very strong Balmer emission, the other is an unresolved source with numerous broad emission lines and a strong absorption line.