J/A+A/651/A64ivo://CDS.VizieR/J/A+A/651/A64doi:10.26093/cds/vizier.36510064CDSLambert S.Liu N.Arias E.F.Barache C.Souchay J.Taris F.Liu J.C.,Zhu Z.2023-02-04T18:17:19Z2021-07-13T08:31:43ZCDS support team

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

cds-question@unistra.frastrometryastronomical-reference-materialsinterferometryquasarsWe aim to study the relative positions of quasar emission centers at different wavelengths in order to help link the various realizations of the International Celestial Reference System (ICRS), and to unveil systematic uncertainties and individual source behavior at different wavelengths. We based our study on four catalogs representing the ICRS, the ICRF3 positions in the three VLBI bands X, K, and Ka, and the Gaia EDR3 catalog in optical wavelengths. We complemented radio source positions with jet kinematics results from the MOJAVE team, allowing us to obtain jet directions on the sky. A six-parameter deformation model was used to remove systematic uncertainties present in the different catalogs. For a set of 194 objects common to the four catalogs and to the objects whose jet kinematics was studied by the MOJAVE team, we computed the orientation between positions at the different wavelengths and with respect to the directions of the jets. We find that the majority of these objects have their radio-to-optical vector along the jet, with the optical centroid downstream from the radio centroids, and that the K and Ka centroids are preferably upstream in the jet with respect to the X centroid, which is consistent with the paradigm of a simple core-jet model. For a population of multiwavelength positions aligned along the jet, astrometric information can therefore be used to measure the direction of the jet independently of imaging. In addition, we find several sources for which the optical centroid coincides with stationary radio features with a relatively high fraction of polarization, indicating optical emission dominated by a synchrotron process in the jet.2021A&A...651A..64Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/651/A64CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJ/874/43 : MOJAVE XVII. Parsec-scale jet kinematics of AGNs (Lister+, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/651/A64https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/651/A64http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/651/A64https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/651/A64https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/651/A64http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/651/A64GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/651/A64/tablea1 (Length and orientation of astrometric position difference vectors and of the jets)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/651/A64/tablea1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/651/A64/tablea1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/651/A64/tablea1?GETtext/xml+votable180.050000true1.4882538.33752780.0055555555555555566/532 579 700 911 968 1154 1509 1546 1622 1702 2143 2280 2414 2836 3024 3096 3675 3820 3951 4285 4572 4695 4770 4820 5154 5423 5448 5458 5597 5693 5817 5848 6164 6368 6496 6507 6641 6815 6853 6948 6963 6996 7181 7371 7389 7896 8031 8199 8299 8487 8615 8915 9248 9442 9545 9612 9632 9676 9688 9998 10163 10249 10422 11430 11639 11715 12047 12352 12475 12580 12619 13156 13230 13352 13410 13693 13927 14520 15023 15147 15494 16027 16247 16298 17351 17516 17541 17579 18002 18005 18035 18037 18214 18378 18457 18624 18661 18718 18907 19088 19101 19190 19271 19370 19487 19523 19567 19622 19831 20099 20468 20836 21121 21266 21358 21564 21758 21768 21924 21935 21960 21968 22363 22396 22501 22658 22917 23015 23099 23121 23127 23323 23416 23786 24084 24571 24828 24845 25016 25196 25255 25503 25630 25742 25818 25864 26115 26131 26303 26363 27060 27310 27423 28083 28339 28454 28479 28517 29016 29570 29620 29675 29714 31391 31399 31430 31451 31559 31664 31894 32311 32660 36188 36602 38763 40434 40527 40730 40762 40766 42901 42980 44147 44247 44730 44908 46964 48023 48123 48610 48798 48846 48965 49071https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/651/A64?format=asciidefaultJ/A+A/651/A64/tablea1Length and orientation of astrometric position difference vectors and of the jetsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIERSRadio source IERS designationmeta.id;meta.maincharLXKLength of the X-to-K difference vectormaspos.distance;arith.difffloate_LXKUncertainty of the X-to-K difference vectormasstat.errorfloatPXKPosition angle of the X-to-K difference vectordegpos.posAnginte_PXKUncertainty of the position angle of the X-to-K difference vectordegstat.errorintLXKaLength of the X-to-Ka difference vectormaspos.distance;arith.difffloate_LXKaUncertainty of the X-to-Ka difference vectormasstat.errorfloatPXKaPosition angle of the X-to-Ka difference vectordegpos.posAnginte_PXKaUncertainty of the position angle of the X-to-Ka difference vectordegstat.errorintLXOLength of the X-to-O difference vectormaspos.distance;arith.difffloate_LXOUncertainty of the X-to-O difference vectormasstat.errorfloatPXOPosition angle of the X-to-O difference vectordegpos.posAnginte_PXOUncertainty of the position angle of the X-to-O difference vectordegstat.errorintPjetPosition angle of the 15GHz radio jetdegpos.posAnginte_PjetUncertainty of the position angle of the 15GHz radio jetdegstat.errorintFileNameName of the fits image in subdirectory imgmeta.id;meta.fitscharSimbadSimbad column added by the CDSmeta.ref.urlchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.main