J/ApJ/766/37ivo://CDS.VizieR/J/ApJ/766/37doi:10.26093/cds/vizier.17660037CDSSingal A.K.Singh R.L.2017-10-16T14:58:09Z2014-12-10T15:41:58ZCDS support team

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

cds-question@unistra.fractive-galactic-nucleiquasarsredshiftedradio-continuum-emissionIn the currently popular orientation-based unified scheme, a radio galaxy appears as a quasar when its principal radio-axis happens to be oriented within a certain cone opening angle around the observer's line of sight. Due to geometrical projection, the observed sizes of quasars should therefore appear smaller than those of radio galaxies. We show that this simple, unambiguous prediction of the unified scheme is not borne out by the actually observed angular sizes of radio galaxies and quasars. Except in the original 3CR sample, based on which the unified scheme was proposed, in other much larger samples no statistically significant difference is apparent in the size distributions of radio galaxies and quasars. The population of low-excitation radio galaxies with apparently no hidden quasars inside, which might explain the observed excess number of radio galaxies at low redshifts, cannot account for the absence of any foreshortening of the sizes of quasars at large redshifts. On the other hand, from infrared and X-ray studies, there is evidence of a hidden quasar within a dusty torus in many radio galaxies, at z>0.5. It is difficult to reconcile this with the absence of foreshortening of quasar sizes at even these redshifts, and perhaps one has to allow that the major radio axis may not have anything to do with the optical axis of the torus. Otherwise, to resolve the dichotomy of radio galaxies and quasars, a scheme quite different from the present might be required.2013ApJ...766...37Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/766/37CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVIII/16 : Molonglo Reference Catalogue (MRC) of Radio Sources (Large+ 1991)VIII/1 : The 3C and 3CR Catalogues (Edge+ 1959-1962)J/AJ/148/16 : Updated 3CRR sample of radio sources (Singal, 2014)J/ApJS/177/148 : 3CR radio source counterparts HST survey. II. (Floyd+, 2008)J/AJ/130/23 : Spectrophotometry of 3CR lobe-dominated quasars (Aars+, 2005)J/ApJS/107/19 : MRC/1Jy Radio source survey. I. (McCarthy+ 1996)J/A+A/303/420 : Radio galaxies and quasars (Chyzy+, 1995)J/MNRAS/204/151 : Bright radio sources at 178 MHz (3CRR) (Laing+ 1983)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/766/37https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/766/37http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/766/37https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/766/37https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/766/37http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/766/37GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/766/37/table1 (Radio and optical data for our sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/766/37/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/766/37/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/766/37/table1?GETtext/xml+votable180.050000true0.9491667-23.49444440.0055555555555555566/16471 16476 16494 16496 16500 16501 16509 16511 16561 16602 16614 16617 16619 16621 16625 16632 16635 16638 16659 16668 16676 16684 16685 16686 16688 16693 16696 16697 16702 16704 16706 16708 16709 16712 16722 16725 16773 16776 16782 16783 16784 16787 16792 16802 16900 16901 16902 16904 16915 16916 16918 16923 16929 16934 16938 16950 16955 16956 16957 16961 16967 16993 17026 17028 17031 17033 17037 17048 17056 20583 20635 20673 20674 20675 20706 20708 20715 20722 20726 20728 20731 20998 21009 21010 21020 21033 21038 21049 21067 21088 21090 21122 21126 21129 21138 21154 24665 24666 24684 24687 24691 24695 24696 24698 24700 24724 24742 24753 24761 24762 24765 24766 24771 24775 24785 24803 24809 24818 24819 24825 24830 24832 24835 24841 24846 24861 24867 24871 24873 24881 24888 24892 24893 24902 24903 24907 24908 24910 24920 24932 24967 24974 24980 24993 25096 25105 25108 25110 25112 25116 25121 25131 25136 25142 25144 25145 25147 25164 25170 25216 25226 25228 25231 25233 34668 34669 34672 34715 34717 34730 34753 34755 34758 34763 34764 34771 34777 34778 34785 34788 34801 34808 35696 35698 35699 35700 35709 35711 35735 35742 35761 35768 35769 35774 35779 35780 35783 35788 35792 35794 35795 35798 35806 35810 35812 35816 35817 35833 35836 35934 35952 35957 35960 35962 35963 35964 35965 35996 36013 36014 36018 36041 36042 36046 36047 36049 36052 36057 36066 36069 36071 36079 36082 36085 36094 36097 36100 36112 36113 36117 36118 36130 36151 36155 36157 36160 36165 36166 36178 36195 36228 36260 36354 36367 36375 36378 36380 36382 36383 36391 36392 36402 36408 36410 36418 36421 36435 36442 36484 36487 36488 36489 36493 36496 36497 36512 38763 38765 38771 38772 38774 38777 38804 38805 38810 38815 38829 38833 38836 38838 38843 38845 38855 38857 38860 38872 38884 38885 38887 38891 38893 38895 38897 38898 38899 38901 38904 38906 38911 40199 40209 40215 40216 40217 40219 40223 40228 40240 40246 40254 40255 40257 40264 40265 40268 40275 40290 40339 43862 43870 43887 43900 43931 43946 43947 43949 43957 43962 43964 43966 43967 43981 43982 43988 44009 44019 44022 44028 44579 44586 44587 44672 44677 44678 44679 44681 44684 46965 47006 47007 47020 47022 47023 47028 47033 47040 47047 47049 47058 47061 47078 47080 47082 47091 47092 47100 47101 48219 48238 48239 48240 48242 48250 48252 48283 48286 48295 48308 48309 48319 48323 48324 48330 48337 48340 48341 48344 48347 48350 48355 48356 48363 48364 48369 48371 48375 48386 48390 48392 48398 48403 48404 48406 48420 48427 48428 48429 48433 48436 48449 48463 48467 48484 48488 48489 48513 48516 48523 48529 48530 48705 48711 48712 48714 48719 48724 48736 48737 487382.703436334132769e-25 2.703436334132769e-25https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/766/37?format=asciiOpticalRadiodefaultJ/ApJ/766/37/table1Radio and optical data for our samplerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMRCMRC source name (<MRC HHMM+DDdA> in Simbad)meta.id;meta.maincharS408[0.9/28.1] Flux density at 408MHzJyphot.flux.density;em.radio.200-400MHzfloatalpha[0.5/1.6]? Spectral index; S{propto}{nu}^-{alpha}^spect.indexfloatnullableOT[GQU] Nature of optical object: G=Galaxy, Q=Quasar, U=Unidentifiedmeta.code.classcharz[0.03/3.2]? Redshift when availablesrc.redshiftfloatnullabletheta[0.9/372]? Largest angular size {theta}arcsecphys.angSize;stat.maxfloatnullableSize[3/1202]? Linear sizekpcphys.sizeintnullableP408? The 408MHz spectral luminosityW/Hzphys.luminosity;em.radio.400-750MHzfloatnullableSimbadSimbad column added by the CDSmeta.ref.urlcharNEDSimbad column added by the CDSmeta.ref.urlchar_RAPositions from SIMBAD database (right ascension part)degpos.eq.ra;meta.main_DEPositions from SIMBAD database (declination part)degpos.eq.dec;meta.main