J/ApJ/756/29ivo://CDS.VizieR/J/ApJ/756/29doi:10.26093/cds/vizier.17560029CDSKoay J.Y.Macquart J.-P.Rickett B.J.Bignall H.E.Jauncey D.L.,Pursimo T.Reynolds C.Lovell J.E.J.Kedziora-Chudczer L.Ojha R.2017-09-27T05:56:02Z2014-04-28T09:25:14ZCDS support team

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

cds-question@unistra.fractive-galactic-nucleiradio-sourcesinterstellar-mediumThe fraction of compact active galactic nuclei (AGNs) that exhibit interstellar scintillation (ISS) at radio wavelengths, as well as their scintillation amplitudes, have been found to decrease significantly for sources at redshifts z>~2. This can be attributed to an increase in the angular sizes of the {mu}as-scale cores or a decrease in the flux densities of the compact {mu}as cores relative to that of the mas-scale components with increasing redshift, possibly arising from (1) the space-time curvature of an expanding universe, (2) AGN evolution, (3) source selection biases, (4) scatter broadening in the ionized intergalactic medium (IGM) and intervening galaxies, or (5) gravitational lensing. We examine the frequency scaling of this redshift dependence of ISS to determine its origin, using data from a dual-frequency survey of ISS of 128 sources at 0<~z<~4. We present a novel method of analysis which accounts for selection effects in the source sample.2012ApJ...756...29Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/756/29CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/249 : WHAM Northern Sky Survey, V-1.1 (Haffner+, 2003)VIII/72 : CLASS survey of radio sources (Myers+, 2003)J/AJ/142/108 : Radio variability of compact, flat-spectrum AGNs (Koay+, 2011)J/ApJ/737/45 : Variable 1.4GHz radio sources from NVSS and FIRST (Ofek+, 2011)J/ApJS/194/29 : Observations of blazars at 15GHz (Richards+, 2011)J/A+A/520/A62 : Radio-optical scrutiny of compact AGN (Arshakian+, 2010)J/ApJ/689/108 : MASIV survey. II. First four epochs (Lovell+, 2008)J/AJ/128/1570 : 8.4GHz VLBA observations of scintillating sources (Ojha+, 2004)J/ApJ/614/607 : 8.4GHz obs. of scintillating sources (Ojha+, 2004)J/A+A/421/455 : Interplanetary Scintillation Pushchino Survey (Kopylov+, 2004)J/A+A/416/35 : Radio Emission from VLA FIRST Survey AGN (Wadadekar, 2004)J/A+A/342/378 : 6 and 20cm flux densities of radio galaxies (Gurvits+ 1999)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/756/29https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/756/29http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/756/29https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/756/29https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/756/29http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/756/29GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/756/29/table1 (List of sources and their observed properties)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/756/29/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/756/29/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/756/29/table1?GETtext/xml+votable180.050000true2.43112515.22719440.0055555555555555566/124 180 197 579 597 625 1152 1154 1584 1593 1610 2053 2087 2098 2531 2978 3886 4027 4405 4446 5035 5817 5848 6173 6507 6631 6790 6853 7148 7227 7235 7570 7623 7709 7724 7951 8073 8131 8324 9248 9545 9560 9641 9723 9813 9961 9976 10198 10550 11037 11398 11640 11805 11821 11845 11878 11977 12001 12133 12311 12352 12397 12619 12621 12851 13352 13414 13427 13739 13792 14495 14820 14985 14996 15123 15277 15945 15947 16170 16351 18035 18209 18806 18923 19174 19308 19357 19676 19743 20218 21935 21960 21968 22359 22363 22375 22396 22433 22965 23226 23274 23306 23416 23478 23730 23786 24084 24123 27322 27323 27583 27605 28383 28479 31190 31202 31229 31529 31649 31792 31894 32035 32101 32247 32311 32328 32391 327643.2467741526420485e-24 5.5658981862942334e-24https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/756/29?format=asciiRadiodefaultJ/ApJ/756/29/table1List of sources and their observed propertiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMASIVIAU name (JHHMM+DDMM)meta.id;meta.maincharS4.9[0.05/4.31] Mean 4.9GHz flux densityJyphot.flux.density;em.radio.3-6GHzfloatS8.4[0.05/5.25] Mean 8.4GHz flux density (1)Jyphot.flux.density;em.radio.6-12GHzfloatalphaSpectral index {alpha} (1)spect.indexfloatD4.9The 4.9GHz structure function D({tau}=4d) (6)src.var.indexdoublee_D4.9The 95% confidence error in D4.9stat.errordoubleD8.4The 8.4GHz structure function D({tau}=4d) (6)src.var.indexdoublee_D8.4The 95% confidence error in D8.4 (1)stat.errordoubleRD? The D8.4/D4.9 ratio (2)stat.fit.omcfloatnullablee_RD? The 95% confidence error in RDstat.errorfloatnullableOpIDOptical identification (3)src.classcharz[0.1/4] Source redshift (4)src.redshiftfloatIHa[-0.2/147] Line-of-sight H{alpha} intensity (5)1e+10m**-2.s**-1phot.flux.densityfloatPapIDisplay the data from Paper I (Cat. J/AJ/142/108)meta.ref.urlcharSimbadSimbad column added by the CDSmeta.ref.urlcharNEDSimbad column added by the CDSmeta.refchar_RAPositons from the MASIV catalog (J/ApJ/689/108) (right ascension part)degpos.eq.ra;meta.main_DEPositons from the MASIV catalog (J/ApJ/689/108) (declination part)degpos.eq.dec;meta.main