J/ApJS/98/1 First Caltech-Jodrell Bank VLBI Survey. I. (Polatidis+ 1995)
The First Caltech-Jodrell Bank VLBI survey. I. Lambda = 18 centimeter
observations of 87 sources
Polatidis A.G., Wilkinson P.N., Xu W., Readhead A.C.S.,
Pearson T.J., Taylor G.B., Vermeulen R.C.
<Astrophys. J. Suppl. Ser. 98, 1 (1995)>
=1995ApJS...98....1P 1995ApJS...98....1P
ADC_Keywords: VLBI ; QSOs ; Radio sources
Keywords: quasars: general - radio continuum: galaxies - surveys -
techniques: interferometric
Abstract:
We present the first results from the first Caltech-Jodrell Bank VLBI
survey (the CJ1 survey). The CJ1 sample includes 135 radio sources
with total flux density 1.3Jy>S_6cm≥0.7Jy, declination
delta_1950≥35deg, and Galactic latitude |b^II|>10deg. It extends the
flux density limit of the complete "PR" sample studied by Pearson &
Readhead from 1.3 to 0.7Jy and increases the total number of sources
from 65 to 200. The complete survey includes VLBI images at both
lambda-18 and 6cm of all objects in the extended sample that have
cores strong enough to be mapped with the Mark II VLBI system. These
images provide a large enough sample to study, for example, the
variety of morphologies exhibited by compact radio sources,
cosmological evolution, superluminal motion, and misalignment between
parsec-scale and kiloparsec-scale radio structures. In this paper we
present lambda-18cm VLBI observations of 56 CJ1 and 31 PR sources made
in 1990-1991, including images of 82 sources. The observations were
made with a "snapshot" technique in which each source was observed in
three 20-30-minute scans using an array of 12-16 antennas. The images
have resolution 3-10mas and dynamic range greater than 100:1. Later
papers in the series will present the remaining lambda-18cm
observations, the lambda-6cm observations, and the analysis and
interpretation of the results.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 89 135 The complete CJ1 sample
table2.dat 84 31 Sources from the PR sample observed at 18 cm
table4.dat 74 82 Map parameters
table5 53 236 Gaussian models
fig/* . 165 Maps
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See also:
J/ApJS/98/33 : First Caltech-Jodrell Bank VLBI Survey. II (Thakkar+ 1995)
J/ApJS/99/297 : First Caltech-Jodrell Bank VLBI Survey. III (Xu+ 1995)
J/ApJS/95/345 : Second Caltech-Jodrell Bank VLBI Survey. I. (Taylor+ 1994)
J/ApJS/100/1 : Second Caltech-Jodrell Bank VLBI Survey. II (Henstock+ 1995)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- CJ1 B1950 source name according to IAU convention
10- 11 I2 h RAh Right ascension, J2000.0
13- 14 I2 min RAm Right ascension, J2000.0
16- 21 F6.3 s RAs Right ascension, J2000.0
25- 26 I2 deg DEd Declination, J2000.0
28- 29 I2 arcmin DEm Declination, J2000.0
31- 35 F5.2 arcsec DEs *Declination, J2000.0
46- 49 F4.2 Jy S11cm *Total flux density at 11 cm
52- 55 F4.2 Jy S6cm *Total flux density at 6 cm
58- 61 F4.2 Jy S2.8cm *Total flux density at 2.8 cm
63- 64 A2 --- ID *Optical identification
66- 69 F4.1 mag V ? Apparent V magnitude
70 A1 --- n_z [f>] 'f' - featureless spectrum, '>' - limit
71- 76 F6.4 --- z *? Redshift
78- 81 I4 yr OBSy ? Date of VLBI observations (year)
83- 84 I2 --- OBSm ? Date of VLBI observations (month)
85- 86 A2 --- n_OBSy *Notes on observation date
88- 89 I2 --- r_OBS *[1/18]? Reference to published observation
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Note on DEs:
Positions specified with a precision of 0.01" are from the Jodrell Bank-
VLA Astrometric Survey (Patnaik et al. 1992MNRAS.254..655P 1992MNRAS.254..655P, Tables
2 and 4; and unpublished observations); the remaining positions have
been compiled from a variety of publications via the NASA Extragalactic
Database (NED).
Note on S11cm:
Total flux density at 11cm from Pauliny-Toth et al. 1978AJ.....83..451P 1978AJ.....83..451P
Note on S6cm:
Total flux density at 6cm from Kuhr et al. 1981AJ.....86..854K 1981AJ.....86..854K
Note on S2.8cm:
Total flux density at 3.6cm from Kuhr et al. 1981AJ.....86..854K 1981AJ.....86..854K
Note on ID: Optical identification:
BL - BL Lac object; EF - Empty Field;
G - Galaxy; Q - Quasar; SO - Stellar object.
Note on z:
See notes to Table 1 in the printed paper for references.
Note on n_OBSy:
Parentheses indicate that the source was observed but not mapped; in three
cases (marked with an asterisk) this is because the a priori position
assumed for correlations was wrong, while in the other cases the
source was too heavily resolved. A blank field indicates that the
source was not observed because it does not contain a compact
component strong enough for detection with Mark-II VLBI.
Note to r_OBS:
1: Xu et al. 1994AJ....108..395X 1994AJ....108..395X
2: Stickel & Khuer 1994 J/A+AS/103/349
3: Stickel, Meisenheimer & Khuer 1994 ≪J/A+AS/105/211>
4: Spinrad et al. 1985 J/PASP/97/932
5: Browne et al. 1993MNRAS.263L..32B 1993MNRAS.263L..32B
6: Henstock, Browne & Wilkinson 1995 J/ApJS/100/1
7: Jackson 1989 (Ph.D. thesis, Univ. of Manchester)
8: Palomar Observatory Sky Survey
9: Hewitt & Burbidge 1993 VII/158
10: Eckart et al. 1987A&AS...67..121E 1987A&AS...67..121E
11: Sanghera 1992 (Ph.D. thesis, Univ. of Manchester)
12: Fanti et al. 1985A&A...143..292F 1985A&A...143..292F
13: Dallacasa et al. 1995A&A...295...27D 1995A&A...295...27D
14: Foulsham 1989 (M.Sc. thesis, Univ. of Manchester)
15: Jones et al. 1986ApJ...305..684J 1986ApJ...305..684J
16: Dallacasa et al. 1990 (in Compact Steep-Spectrum and GHz-peaked Spectrum
Radio Sources, ed. C. Fanti, D. Fanti. C.P. O'Dea & R.T. Schilizzi,
Bologna: Consiglio Nazionale delle Ricerche, 77
17: Sanghera 1989 (M.Sc. thesis, Univ. of Manchester)
18: Lawrence, Zucker, Readhead, Unwin, Pearson & Xu, 1995, ApJS, submitted
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- CJ1 B1950 source name according to IAU convention
10- 11 I2 h RAh Right ascension, J2000.0
13- 14 I2 min RAm Right ascension, J2000.0
16- 21 F6.3 s RAs Right ascension, J2000.0
25- 26 I2 deg DEd Declination, J2000.0
28- 29 I2 arcmin DEm Declination, J2000.0
31- 35 F5.2 arcsec DEs *Declination, J2000.0
45- 49 F5.2 Jy S11cm *Total flux density at 11 cm
52- 55 F4.2 Jy S6cm *Total flux density at 6 cm
57- 61 F5.2 Jy S2.8cm *? Total flux density at 2.8 cm
63- 64 A2 --- ID *Optical identification
66- 69 F4.1 mag Vmag ? Apparent V magnitude
71- 76 F6.4 --- z *? Redshift from Lawrence et al.
78- 81 I4 yr OBSy Date of VLBI observations (year)
83- 84 I2 --- OBSm Date of VLBI observations (month)
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Note on DEs:
Positions specified with a precision of 0.01" are from the Jodrell Bank-
VLA Astrometric Survey (Patnaik et al. 1992MNRAS.254..655P 1992MNRAS.254..655P, Tables
2 and 4; and unpublished observations); the remaining positions have
been compiled from a variety of publications via the NASA Extragalactic
Database (NED).
Note on S11cm:
Total flux density at 11cm from Pauliny-Toth et al. 1978AJ.....83..451P 1978AJ.....83..451P
Note on S6cm:
Total flux density at 6cm from Kuhr et al. 1981AJ.....86..854K 1981AJ.....86..854K
Note on S2.8cm:
Total flux density at 3.6cm from Kuhr et al. 1981AJ.....86..854K 1981AJ.....86..854K
Note on ID:
Optical identification: BL - BL Lac object; G - Galaxy; Q - Quasar
Note on z:
Lawrence, Zucker, Readhead, Unwin, Pearson & Xu, 1995, ApJS, submitted
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- CJ1 B1950 source name according to IAU convention
10- 13 I4 yr OBSy Date of VLBI observation (year)
15- 16 I2 --- OBSm Date of VLBI observation (month)
18- 20 A3 --- Samp VLBI sample (CJ1 or PR) source belongs to
22- 26 F5.2 mas a18cmn FWHM of major axis of the restoring beam
28- 32 F5.2 mas b18cmn FWHM of minor axis of the restoring beam
35- 37 I3 deg PA18cmn [-83/88] Position angle of major axis,
north through east
39- 42 I4 mJy S18cmn *Peak flux density, naturally weighted map
44- 47 F4.2 mJy e_S18cmn *Off source rms, naturally weighted map
49- 53 F5.2 mas a18cmt ? FWHM of major axis of tapered map
restoring beam
55- 59 F5.2 mas b18cmt ? FWHM of minor axis of tapered map
restoring beam
62- 64 I3 deg PA18cmt [-75/70]? Position angle of major axis,
N through E
66- 69 I4 mJy S18cmt *? Peak flux density, tapered map
71- 74 F4.2 mJy e_S18cmt *? Off source rms, tapered map
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Note on S18cmn, e_S18cmn, S18cmt, e_S18cmt: Data are in mJy/beam
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Byte-by-byte Description of file: table5
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Bytes Format Units Label Explanations
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1- 8 A8 --- CJ1 B1950 source name according to IAU convention
10- 14 F5.3 Jy S Flux density of component
16- 21 F6.2 mas Rad *Radius of component
23- 28 F6.1 deg Theta *Angle to component
30- 35 F6.2 mas a FWHM of major axis of component
37- 40 F4.2 --- b/a Axial ratio of major to minor axis, b/a
42- 47 F6.1 deg Phi Position angle of major axis,
north through east
49- 53 F5.3 --- Chi2 ? Chi-squared between the model and the
self-calibrated UV-data
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Note on Rad:
Radius of component, measured from position of first component
Note on Theta:
Angle to component, measured north through east from the position of
the first component
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Origin: AAS CD-ROM series, Volume 4, 1995 Lee Brotzman [ADS] 10-May-95
(End) [CDS] 14-Oct-1996