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 deg2. 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: Lyα + 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 Lyα + 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.
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science