J/ApJ/455/75 CFRS III: 1415+52 and 2215+00 fields (Lilly+ 1995)
The Canada-France redshift survey. III. "Single emission-line" objects,
analysis of repeat observations, and spectroscopic identifications in
the 1415+52 and 2215+00 fields
Lilly S.J., Hammer F., Le Fevre O., Crampton D.
<Astrophys. J. 455, 75 (1995)>
=1995ApJ...455...75L 1995ApJ...455...75L (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, photometry ; Galaxies, spectra ; Redshifts
Keywords: catalogs - galaxies: distances and redshifts - line: identification
Abstract:
This paper is one of a series describing the Canada-France Redshift
Survey (CFRS). It is shown how the shape of the continuum around the
emission line can be used to distinguish between [O II]λ3727 at
z>0.76 and Hα at low redshift in spectra for which only a single
isolated emission line is visible. Based on this, [O II]λ3727
is most likely to be the emission line in most of the single
emission-line galaxies in the CFRS. The statistics of the repeated
observations are analyzed to derive an empirical calibration of the
reliability of the spectroscopic identifications in the CFRS in order
to determine how often additional observations could lead to the
identification of an initially unidentified object and to provide an
estimate of the internal velocity accuracy. Finally, the results of
spectroscopic observations of 413 objects in the 1415+52 and 2215+00
CFRS survey fields are presented.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 99 239 Spectroscopic catalog in the 1415+52 field
table3.dat 94 198 Spectroscopic catalog in the 2215+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/455/88 : CFRS IV: 0300+00 field (Hammer+ 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: table2.dat table3.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- 31 F4.1 arcsec DEs Declination (J2000)
33- 37 F5.2 mag Imag IAB magnitude (1)
39- 43 F5.2 mag V-I ? (V-I)AB colour index (2)
45- 49 F5.2 --- Q ? Compactness parameter;
see CFRS I. (1995ApJ...455...50L 1995ApJ...455...50L)
51- 56 F6.4 --- z ? Redshift
58- 59 I2 --- C Confidence class of spectroscopic
identification (3)
61- 64 I4 0.1nm Lam1 ? Spectroscopic feature (4)
65 A1 --- Cont1 [2a] Spectroscopic feature (4)
66- 69 I4 0.1nm Lam2 ? Spectroscopic feature (4)
70 A1 --- Cont2 [1b] Spectroscopic feature (4)
71- 74 I4 0.1nm Lam3 ? Spectroscopic feature (4)
75 I1 --- Cont3 [1]? Spectroscopic feature (4)
76- 79 I4 0.1nm Lam4 ? Spectroscopic feature (4)
80 A1 --- Cont4 [1a] Spectroscopic feature (4)
81- 84 I4 0.1nm Lam5 ? Spectroscopic feature (4)
85 A1 --- Cont5 [1a] Spectroscopic feature (4)
86- 89 I4 0.1nm Lam6 ? Spectroscopic feature (4)
91- 94 I4 0.1nm Lam7 ? Spectroscopic feature (4)
96- 99 I4 0.1nm Lam8 ? 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 the text 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 and a 2 indicates the multiple features of an M star.
b indicates break, a for 4863a line
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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
Hammer F. et al., Paper IV. =1995ApJ...455...88H 1995ApJ...455...88H, Cat. J/ApJ/455/88
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