J/ApJS/98/1ivo://CDS.VizieR/J/ApJS/98/1doi:10.26093/cds/vizier.20980001CDSPolatidis A.G.Wilkinson P.N.Xu W.Readhead A.C.S.,Pearson T.J.Taylor G.B.Vermeulen R.C.1997-12-09T20:28:39Z1997-12-09T21:28:32ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frvery-long-baseline-interferometryquasarsradio-sourcesWe 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.1995ApJS...98....1Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/98/1CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/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)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/98/1https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/98/1http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/98/1https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/98/1https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/98/1http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/98/1GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/98/1/table1 (The complete CJ1 sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/98/1/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/98/1/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/98/1/table1?GETtext/xml+votable180.050000true3.379712540.860319440.005555555555555556Cone search capability for table J/ApJS/98/1/table2 (Sources from the PR sample observed at 18 cm)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/98/1/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/98/1/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/98/1/table2?GETtext/xml+votable180.050000true17.9054958339.107802780.005555555555555556https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/98/1?format=asciiRadiodefaultJ/ApJS/98/1/table1The complete CJ1 samplerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCJ1B1950 source name according to IAU conventionmeta.id;meta.maincharRAJ2000Right ascension, J2000.0pos.eq.ra;meta.mainDEJ2000Declination, J2000.0pos.eq.dec;meta.mainS11cm*Total flux density at 11 cmJyphot.flux.density;em.radio.1500-3000MHzfloatS6cm*Total flux density at 6 cmJyphot.flux.density;em.radio.3-6GHzfloatS2.8cm*Total flux density at 2.8 cmJyphot.flux.density;em.radio.6-12GHzfloatID*Optical identificationmeta.idcharV? Apparent V magnitudemagphot.mag;em.opt.Vfloatn_z[f>] 'f' - featureless spectrum, '>' - limitmeta.notecharz*? Redshiftsrc.redshiftfloatOBS? Date of VLBI observations (year)time.epochn_OBSy*Notes on observation datemeta.notecharr_OBS*[1/18]? Reference to published observationmeta.refintJ/ApJS/98/1/table2Sources from the PR sample observed at 18 cmrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCJ1B1950 source name according to IAU conventionmeta.id;meta.maincharRAJ2000Right ascension, J2000.0pos.eq.ra;meta.mainDEJ2000Declination, J2000.0pos.eq.dec;meta.mainS11cm*Total flux density at 11 cmJyphot.flux.density;em.radio.1500-3000MHzfloatS6cm*Total flux density at 6 cmJyphot.flux.density;em.radio.3-6GHzfloatS2.8cm*? Total flux density at 2.8 cmJyphot.flux.density;em.radio.6-12GHzfloatID*Optical identificationmeta.idcharVmag? Apparent V magnitudemagphot.mag;em.opt.Vfloatz*? Redshift from Lawrence et al.src.redshiftfloatOBSDate of VLBI observations (year)time.epochJ/ApJS/98/1/table4Map parametersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCJ1B1950 source name according to IAU conventionmeta.id;meta.maincharOBSDate of VLBI observation (year)time.epochSampVLBI sample (CJ1 or PR) source belongs tometa.idchara18cmnFWHM of major axis of the restoring beammasphys.angSize;instr.beamfloatb18cmnFWHM of minor axis of the restoring beammasphys.angSize;instr.beamfloatPA18cmn[-83/88] Position angle of major axis, north through eastdegpos.posAngintS18cmn*Peak flux density, naturally weighted mapmJyphot.flux.density;em.radio.1500-3000MHzinte_S18cmn*Off source rms, naturally weighted mapmJystat.errorfloata18cmt? FWHM of major axis of tapered map restoring beammasphys.angSizefloatb18cmt? FWHM of minor axis of tapered map restoring beammasphys.angSizefloatPA18cmt[-75/70]? Position angle of major axis, N through Edegpos.posAngintS18cmt*? Peak flux density, tapered mapmJyphot.flux.density;em.radio.1500-3000MHzinte_S18cmt*? Off source rms, tapered mapmJystat.errorfloatJ/ApJS/98/1/table5Gaussian modelsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCJ1B1950 source name according to IAU conventionmeta.id;meta.maincharSFlux density of componentJyphot.flux.density;em.radio.3-6GHzfloatRad*Radius of componentmasphys.angSize;srcfloatTheta*Angle to componentdegpos.posAngfloataFWHM of major axis of componentmasphys.angSizefloatb/aAxial ratio of major to minor axis, b/aphys.size;arith.ratiofloatPhiPosition angle of major axis, north through eastdegpos.posAngfloatChi2? Chi-squared between the model and the self-calibrated UV-datastat.fit.chi2float