J/AJ/146/5ivo://CDS.VizieR/J/AJ/146/5doi:10.26093/cds/vizier.51460005CDSPetrov L.2017-10-02T19:28:42Z2014-06-04T15:14:37ZCDS support team

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

cds-question@unistra.frvery-long-baseline-interferometryradio-sourcessurveysFuture space-borne astrometry missions, such as Gaia, will be able to determine the optical positions of hundreds of quasars with submilliarcsecond accuracies comparable to those achieved in radio by very long baseline interferometry (VLBI). Comparisons of coordinate systems from space-borne missions and VLBI will be very important, first for investigations of possible systematic errors and second for investigations of possible shifts between centroids of radio and optical emissions in active galactic nuclei. In order to make such a comparison more robust, a program for densification of the grid of radio sources detectable with both VLBI and Gaia was launched in 2006. Program sources are 398 quasars with declinations >-10{deg} that are brighter than 18mag at the V band. The first two observing campaigns were run in 2007-2008. In the third campaign, a set of 291 objects from that list was observed with the VLBA+EVN in 2010-2011 with the primary goal of producing their images with milliarcsecond resolution. In this paper, following the method of absolute astrometry, coordinates of observed sources have been derived with milliarcsecond accuracies from analysis of these observations. The catalog of positions of 295 target sources, estimates of their correlated flux densities at 2.2 and 8.4GHz, and their images are presented. The accuracies of source coordinates are in a range of 2-200mas, with a median of 3.2mas.2013AJ....146....5Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/146/5CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/258 : Quasars and Active Galactic Nuclei (13th Ed.) (Veron+ 2010)I/323 : International Celestial Reference Frame 2, ICRF2 (Ma+, 2009)I/251 : VLBI International Celestial Reference Frame ICRF (Ma+ 1997)J/A+A/544/A34 : Bright AGN VLBI imaging study at 2 and 8GHzJ/MNRAS/416/1097 : The EVN Galactic Plane Survey - EGaPS (Petrov, 2012)J/MNRAS/414/2528 : LBA Calibrator Survey (LCS1) (Petrov+, 2011)J/AJ/142/105 : Optically Bright Extragalactic Radio Sources (Petrov+, 2011)J/AJ/142/35 : The VLBA Galactic Plane Survey (VGaPS) (Petrov+, 2011)J/A+A/526/A102 : VLBI imaging of 105 extragalactic radio sourcesJ/A+A/520/A113 : VLBI detection of 398 extragalactic radio sourcesJ/AJ/136/580 : Sixth VLBA calibrator survey: VCS6 (Petrov+, 2008)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/146/5https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/146/5http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/146/5https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/146/5https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/146/5http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/146/5GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/146/5/table2 (The OBRS-2 source VLBI position catalog)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/146/5/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/146/5/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/146/5/table2?GETtext/xml+votable180.050000true0.348727504176.541927094440.0055555555555555566/29 49 171 447 615 988 1535 1702 2074 2164 2217 2225 2257 2295 2456 2619 2630 2650 2762 3930 3932 4103 4143 4232 4253 4322 4333 4347 4369 4472 4568 4693 4705 4882 4888 4892 4947 5091 5169 5202 5244 5361 5364 5379 5439 5462 5483 5510 5528 5588 5846 5918 5940 5958 5985 6021 6143 6173 6204 6206 6209 6237 6362 6515 6534 6618 6648 6723 6889 7176 7186 7223 7285 7341 7354 7404 7448 7469 7488 7495 7518 7576 7604 7640 7699 7779 7896 8067 8071 8080 8117 8300 8315 8372 8374 8415 8556 8595 8652 8674 8716 8753 8758 8938 8951 8972 9049 9181 9196 9311 9372 9383 9385 9463 9614 9684 9716 9877 9908 9955 10123 10149 10152 10183 10318 10402 10433 10448 10461 10472 10512 10561 10563 10572 10596 10605 10650 10688 10715 10755 10893 10938 10948 10987 10994 10996 10999 11033 11065 11126 11143 11290 11345 11362 11374 11386 11429 11440 11627 11682 11706 11736 11786 11813 11829 11854 11924 11936 12038 12231 12772 12886 12924 13464 13783 15059 15269 16036 16039 16042 17346 17639 17690 17730 17979 18023 18125 18209 18270 18402 18538 18540 18756 18895 18992 19036 19099 19190 19214 19287 19315 19370 19397 19413 19466 19503 19507 19671 19698 19700 19757 19789 19907 20005 20020 20032 20065 20083 20116 20286 20327 20389 20390 22372 22389 22914 23085 23181 23222 23427 24027 25810 25902 25912 25977 26036 26083 26090 26298 26305 26322 26373 26382 26416 26499 26595 26615 26939 27062 27217 27253 27394 27481 27560 27602 27610 27650 27656 27722 27750 27755 27815 27846 28043 28132 28138 28199 28352 28454 28482 28517 28539 28616 28647 28666 32427 32570 32647 36862 45006 45038 45044 48983 48985 490151.457735337063324e-24 5.5658981862942334e-24https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/146/5?format=asciiRadiodefaultJ/AJ/146/5/table2The OBRS-2 source VLBI position catalogJNameIAU source name (JHHMM+DDMM)meta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBNameIVS source name (HHMM+DDd; B1950) (1)meta.id;meta.maincharRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.maine_RAJ2000Uncertainty in RAs (without cos{delta} factor)masstat.error;pos.eq.rafloatDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.maine_DEJ2000Uncertainty in DEsmasstat.error;pos.eq.decfloatCorr[-1/1] Correlation coefficient between the uncertainties in RAs and DEsstat.correlationfloatB[SX] Band used for deriving positions: S (2.2GHz) or X (8.4GHz)instr.bandpasscharNS[0/385] Number of used observations at S-bandmeta.numberintNX[0/381] Number of used observations at X-bandmeta.numberintF(S)s? Median value of the correlated "short" flux density at the S-band (2.2GHz) (2)Jyphot.flux.density;em.radio.1500-3000MHzfloatnullablel_F(S)l[<] Upper limit flag on FlS (detection limit)meta.code.errorcharF(S)l? Median value of the correlated "long" flux density at the S-band (2.2GHz) (2)Jyphot.flux.density;em.radio.1500-3000MHzfloatnullableF(X)s? Median value of the correlated "short" flux density at the X-band (8.4GHz) (2)Jyphot.flux.density;em.radio.6-12GHzfloatnullablel_F(X)l[<] Upper limit flag on FlX (detection limit)meta.code.errorcharF(X)l? Median value of the correlated "long" flux density at the X-band (8.4GHz) (2)Jyphot.flux.density;em.radio.6-12GHzfloatnullableS[m] A map at S-band is availablemeta.codecharX[m] A map at X-band is availablemeta.codecharSimbadSimbad column added by the CDSmeta.ref.urlchar