J/ApJ/707/114ivo://CDS.VizieR/J/ApJ/707/114doi:10.26093/cds/vizier.17070114CDSFeain I.J.Ekers R.D.Murphy T.Gaensler B.M.Macquart J.-P.,Norris R.P.Cornwell T.J.Johnston-Hollitt M.Ott J.Middelberg E.2026-05-19T14:24:40Z2010-02-06T17:53:36ZCDS support team

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

cds-question@unistra.frradio-galaxiesradio-sourcespolarimetrygalaxy-classification-systemsWe present the results of an Australia Telescope Compact Array 1.4GHz spectropolarimetric aperture synthesis survey of 34deg^2^ centered on Centaurus A-NGC 5128. A catalog of 1005 extragalactic compact radio sources in the field to a continuum flux density of 3mJy/beam is provided along with a table of Faraday rotation measures (RMs) and linear polarized intensities for the 28% of sources with high signal to noise in linear polarization. We use the ensemble of 281 background polarized sources as line-of-sight probes of the structure of the giant radio lobes of Centaurus A. This is the first time such a method has been applied to radio galaxy lobes and we explain how it differs from the conventional methods that are often complicated by depth and beam depolarization effects. Assuming a magnetic field strength in the lobes of 1.3B1uG, where B1=1 is implied by equipartition between magnetic fields and relativistic particles, the upper limit we derive on the maximum possible difference between the average RM of 121 sources behind Centaurus A and the average RM of the 160 sources along sightlines outside Centaurus A implies an upper limit on the volume-averaged thermal plasma density in the giant radio lobes of <ne><5x10^-5^B1^-1^cm^-3^. We use an RM structure function analysis and report the detection of a turbulent RM signal, with rms=17rad/m^2^ and scale size 0.3deg, associated with the southern giant lobe. We cannot verify whether this signal arises from turbulent structure throughout the lobe or only in a thin skin (or sheath) around the edge, although we favor the latter. The RM signal is modeled as possibly arising from a thin skin with a thermal plasma density equivalent to the Centaurus intragroup medium density and a coherent magnetic field that reverses its sign on a spatial scale of 20kpc. For a thermal density of n1 10^-3^cm^-3^, the skin magnetic field strength is 0.8n1^-1^uG.2009ApJ...707..114Fhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/707/114CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJS/45/97 : Extragal. radio sources Faraday rotation (Simard-Normandin 1981)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/707/114https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/707/114http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/707/114https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/707/114https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/707/114http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/707/114GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/707/114/table2 (Radio continuum properties of 1005 sources to 3mJy/beam)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/707/114/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/707/114/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/707/114/table2?GETtext/xml+votable180.050000true198.7194583-40.18233330.005555555555555556Cone search capability for table J/ApJ/707/114/table3 (Polarisation properties of 281 sources)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/707/114/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/707/114/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/707/114/table3?GETtext/xml+votable180.050000true203.4889167-46.69390.0055555555555555565/10807 10813-10814 10858 10900 10903 10944-10946 6/43222-43223 43225 43227 43248-43249 43251 43394 43400 43402 43424 43426 43438 43605-43607 43609 43611 43636-43637 43788 43808https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/707/114?format=asciiOpticalRadiodefaultJ/ApJ/707/114/table2Radio continuum properties of 1005 sources to 3mJy/beamrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintPSimbad column added by the CDSmeta.ref.urlcharNameSource Name (HHMMSS-DDMMSS)meta.id;meta.maincharprimaryRAJ2000Hour of Right Asecension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainpFluxPeak 1.4GHz flux density (mJy/beam)mJyphot.flux.density;em.radio.750-1500MHzfloate_pFluxError in pFluxmJystat.errorfloatiFluxIntegrated 1.4GHz flux density (mJy)mJyphot.flux.density;em.radio.750-1500MHzfloate_iFluxError in iFluxmJystat.errorfloatfMajFitted major axisarcsecphys.angSizefloatfMinFitted minor axisarcsecphys.angSize;srcfloatfPAFitted position angledegpos.posAng;meta.modelledfloatdMaj? Deconvolved major axisarcsecphys.angSizefloatnullabledMin? Deconvolved minor axisarcsecphys.angSize;srcfloatnullabledPA? Deconvolved position angledegpos.posAngfloatnullableJ/ApJ/707/114/table3Polarisation properties of 281 sourcesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameSource Name (HHMMSS-DDMMSS)meta.id;meta.maincharRAJ2000Hour of Right Asecension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainpFluxPeak polarised 1.4GHz flux density (mJy/beam)mJyphot.flux.density;em.radio.750-1500MHzfloatSNRSignal-to-Noise in pFLuxstat.snrfloatRMMeasured Faraday rotation measurerad.m**-2phys.polarization.rotMeasurefloate_RMUncertainty in RM (1)rad.m**-2stat.errorfloatRMcorFaraday rotation measure (2)rad.m**-2phys.polarization.rotMeasurefloat