J/ApJ/455/88 CFRS IV: 0300+00 field (Hammer+ 1995)
The Canada-France Redshift Survey. IV. Spectroscopic selection effects
and 0300+00 field spectroscopic data.
Hammer F., Crampton D., Le Fevre O., Lilly S.J.
<Astrophys. J. 455, 88 (1995)>
=1995ApJ...455...88H 1995ApJ...455...88H (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, photometry ; Galaxies, spectra ; Redshifts
Keywords: catalogs - galaxies: distances and redshifts - methods: observational
Abstract:
Possible surface brightness selection effects in the redshift catalogs
of the Canada-France Redshift Survey are investigated through
comparisons of subsamples of the data. Our analyses demonstrate that
the securing of redshifts is independent of possible biases arising
from surface brightness effects and/or differing galaxy morphologies
and orientations. The unusual geometry of the mask designs for our
spectroscopic observations also do not produce any significant bias.
There is, however, a bias at the highest and lowest redshifts,
especially for absorption-line galaxies at z>1 and z<0.2, due to the
adopted spectral range (4250-8500A). Apart from the latter, we
conclude that our sample of identified galaxies is an unbiased
subsample of the original photometric catalog and is essentially
limited by I-band flux density (17.5<IAB<22.5). Finally,
spectroscopic data for the remaining CFRS field is presented. Data for
272 objects in the 0300+0000 field are given.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 92 272 Spectroscopic catalog in the 0300+00 field
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See also:
J/ApJ/455/60 : CFRS II: 0000-00 and 1000+25 fields (Le Fevre+ 1995)
J/ApJ/455/75 : CFRS III: 1415+52 and 2215+00 fields (Lilly+ 1995)
J/ApJ/464/79 : CFRS XI: High-redshift field galaxies morphology (Schade+ 1996)
J/ApJ/481/49 : CFRS XIV. Field galaxies up to z=1 (Hammer+ 1997)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 7 F7.4 --- CFRS Canada-France Redshift Survey designation
9- 10 I2 h RAh Right ascension (J2000)
12- 13 I2 min RAm Right ascension (J2000)
15- 19 F5.2 s RAs Right ascension (J2000)
21 A1 --- DE- Declination sign
22- 23 I2 deg DEd Declination (J2000)
25- 26 I2 arcmin DEm Declination (J2000)
28- 29 I2 arcsec DEs Declination (J2000)
31- 35 F5.2 mag Imag IAB magnitude (1)
37- 41 F5.2 mag V-I ? (V-I)AB colour index (2)
43- 47 F5.2 --- Q ? Compactness parameter;
see CFRS I. (1995ApJ...455...50L 1995ApJ...455...50L)
49- 54 F6.4 --- z ? Redshift
56- 57 I2 --- C Confidence class of spectroscopic
identification (3)
59- 62 I4 0.1nm Lam1 ? Spectroscopic feature (4)
63 I1 --- Cont1 [1]? Spectroscopic feature (4)
64- 67 I4 0.1nm Lam2 ? Spectroscopic feature (4)
68 I1 --- Cont2 [1]? Spectroscopic feature (4)
69- 72 I4 0.1nm Lam3 ? Spectroscopic feature (4)
73 I1 --- Cont3 [1]? Spectroscopic feature (4)
74- 77 I4 0.1nm Lam4 ? Spectroscopic feature (4)
78 I1 --- Cont4 [1]? Spectroscopic feature (4)
79- 82 I4 0.1nm Lam5 ? Spectroscopic feature (4)
83 I1 --- Cont5 [1]? Spectroscopic feature (4)
84- 87 I4 0.1nm Lam6 ? Spectroscopic feature (4)
88 I1 --- Cont6 [1]? Spectroscopic feature (4)
89- 92 I4 0.1nm Lam7 ? Spectroscopic feature (4)
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Note (1): Measured in isophotal aperture; see CFRS I. (1995ApJ...455...50L 1995ApJ...455...50L)
Note (2): Measured in a 3" aperture; see CFRS I. (1995ApJ...455...50L 1995ApJ...455...50L)
Note (3): Each object identification was assigned a confidence class.
This scheme is somewhat different from a pure "quality" scheme, and
the confidence class reflects the consensus probability that a
redshift measurement is correct and represents the confidence in the
measurement one gets from a combination of S/N, the number and
agreement of features, and the continuum shape.
The notation was set to classes 0-4, 8, 9 12-14, 92-94 as follow:
0-4: 0: when no redshift could be assigned
1: probability of 50% that the measurement was correct
2: probability of more than 75% that the measurement was correct
3: measurement at least 95% secure
4: unquestionably correct identification
8-9: 8: object for which the algorithm indicates that the emission
line is [O II]λ3727
9: object for which the redshift ambiguity still could not be
resolved
12-14: QSO are identified with the same quality notation 1-4 as
galaxies, but a 1 is placed in front, e.g.,
14 is a very secure QSO.
92-94: Objects which do not belong to the main catalog, either because
they have IAB=22.5 or IAB<17.5, because of instrumental
problems but have a redshift determination, or whose photometry
was adjusted fainter than IAB=22.5 after the spectroscopic
observation, are kept in a supplemental catalog and are
identified by a 9 in front of the confidence class, e.g., 93.
The objects in this supplemental catalog may thus have biases
that will not be present in the statistically complete sample.
In any use of these data, attention should be paid to the confident
class that has been assigned to each spectroscopic identification.
Identifications with C=<1 are not used in the CFRS scientific analyses
described elsewhere. See CFRS II (1995ApJ...455...60L 1995ApJ...455...60L) and
CFRS III (1995ApJ...455...75L 1995ApJ...455...75L) for more information.
Note (4): Features noted in the spectra. These are largely self-explanatory,
except that a 1 indicates that the continuum shape supported the
identification in cases in which the number of distinct features
was small
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History: Prepared via OCR at CDS.
References:
Lilly S.J. et al., Paper I. =1995ApJ...455...50L 1995ApJ...455...50L
Le Fevre O. et al.. Paper II. =1995ApJ...455...60L 1995ApJ...455...60L, Cat. J/ApJ/455/60
Lilly S.J. et al., Paper III. =1995ApJ...455...75L 1995ApJ...455...75L, Cat. J/ApJ/455/75
Crampton D. et al., Paper V. =1995ApJ...455...96C 1995ApJ...455...96C
Lilly S. J. et al., Paper VI. =1995ApJ...455..108L 1995ApJ...455..108L
Hammer F. et al., Paper VII. =1995MNRAS.276.1085H 1995MNRAS.276.1085H
Le Fevre O. et al., Paper VIII. =1996ApJ...461..534L 1996ApJ...461..534L
Schade D. et al., Paper IX. =1995ApJ...451L...1S 1995ApJ...451L...1S
Schade D. et al., Paper X. =1996MNRAS.278...95S 1996MNRAS.278...95S
Schade D. et al., Paper XI. =1996ApJ...464...79S 1996ApJ...464...79S, Cat. J/ApJ/464/79
Tresse L. et al., Paper XII. =1996MNRAS.281..847T 1996MNRAS.281..847T
Le Fevre et al., Paper XIII. =1996BCFHT..34...10L 1996BCFHT..34...10L
Hammer et al., Paper XIV. =1997ApJ...481...49H 1997ApJ...481...49H, Cat. J/APJ/481/49
(End) James Marcout, Patricia Bauer [CDS] 27-Mar-1997