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J/AJ/107/1245       QSOs Palomar Transit Grism Survey catalog (Schneider+ 1994)

Spectroscopic CCD surveys for quasars at large redshift. III. The Palomar Transit Grism Survey catalog. Schneider D.P., Schmidt M., Gunn J.E. <Astron. J. 107, 1245 (1994)> =1994AJ....107.1245S (SIMBAD/NED BibCode)
ADC_Keywords: QSOs ; Redshifts ; Abstract: This paper reports the initial results of the Palomar Transit Grism Survey (PTGS). The PTGS was designed to produce a sample of z>2.7 quasars that were identified by well-defined selection criteria. The survey consists of six narrow (∼8.5' wide) strips of sky; the total effective area is 61.47deg2. Low-resolution slitless spectra, covering the wavelength range from 4400 to 7500A, were obtained for approximately 600000 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 III], Mg II, Hbeta+[O III], and Halpha+[S II]. More than two-thirds of the candidates are low-redshift (z<0.45) emission-line galaxies; ninety objects are high-redshift quasars (z>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 ∼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. See also: 1986ApJ...306..411S Schmidt M., Schneider D.P., Gunn J.E. (Paper I) 1986ApJ...310..518S Schmidt M., Schneider D.P., Gunn J.E. (Paper II) 1995AJ....110...68S Schmidt M., Schneider D.P., Gunn J.E. (Paper IV) File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table5 67 1052 Transit grism line detections
Byte-by-byte Description of file: table5
Bytes Format Units Label Explanations
1- 10 A10 --- PTGS Name with multiplicity index (1) 12- 13 I2 h RAh Right ascension (1950) 15- 16 I2 min RAm Right ascension (1950) 18- 21 F4.1 s RAs Right ascension (1950) 23 A1 --- DE- Declination sign 24- 25 I2 deg DEd Declination (1950) 27- 28 I2 arcmin DEm Declination (1950) 30- 31 I2 arcsec DEs Declination (1950) 33- 37 F5.2 mag r4 r4 magnitude calculated from the slit spectrum 39- 43 F5.3 --- z Source redshift based on measurements of the slit spectrum 45- 49 F5.2 mW/m2 -logF Negative logarithm of the detected emission line flux 51- 54 I4 0.1nm EW Observed equivalent width of the emission feature ID measured in the slit spectrum (2) 56- 61 F6.2 --- SN Signal-to-noise ratio of the emission line in the grism spectrum 63- 65 I3 0.1nm W0 Intrinsic observed line width measured from the slit spectrum for ID line 67 I1 --- ID Identification code for line (3)
Note (1): The object name is formed by taking the first digits of the 1950 right ascension and declination; when this nomenclature fails to uniquely define an object, a suffix A, B or C is attached. Note (2): The quoted values for Lyman alpha + N V (ID=1) and Hbeta + [O III] (ID=5) lines refer to the total equivalent width of the blend. A value of 1000 indicates that the continuum in the grism spectrum is negative. Note (3): Code for line identifications: 1 - Lyman alpha + N V 2 - C IV 3 - C [III] 4 - Mg II 5 - Hbeta + [O III] 6 - Halpha+[S II]
History: Prepared via OCR at CDS. Corrected in February 1997 with a file that was supplied by Don P. Schneider to Heinz Andernach in April 1994.
(End) James Marcout, Patricia Bauer [CDS] 13-Feb-1997
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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