J/MNRAS/381/341ivo://CDS.VizieR/J/MNRAS/381/341doi:10.26093/cds/vizier.73810341CDSBroderick J.W.Bryant J.J.Hunstead R.W.Sadler E.M.Murphy T.2024-07-05T20:15:36Z2008-12-16T18:45:02ZCDS support team

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

cds-question@unistra.frsurveysradio-galaxiespolarimetryThis paper introduces a new program to find high-redshift radio galaxies in the Southern hemisphere through ultra-steep spectrum (USS) selection. We define a sample of 234 USS radio sources with spectral indices {alpha}^843^_408_<=-1.0 (S_{nu}_{prop.to}{nu}^alpha^) and flux densities S_408_>=200mJy in a region of 0.35sr, chosen by cross-correlating the revised 408MHz Molonglo Reference Catalogue, the 843MHz Sydney University Molonglo Sky Survey and the 1400MHz NRAO VLA Sky Survey in the overlap region -40{deg}<DE<-30{deg}. We present Australia Telescope Compact Array (ATCA) high-resolution 1384 and 2368MHz radio data for each source, which we use to analyse the morphological, spectral index and polarization properties of our sample. We find that 85 per cent of the sources have observed-frame spectral energy distributions that are straight over the frequency range 408-2368MHz, and that, on average, sources with smaller angular sizes have slightly steeper spectral indices and lower fractional linear polarization. Fractional polarization is anticorrelated with flux density at both 1400 and 2368MHz. We also use the ATCA data to determine observed-frame Faraday rotation measures for half of the sample.2007MNRAS.381..341Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/381/341CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)J/A+AS/93/399 : Optical ident. of USS radio sources (Wieringa+ 1992)J/A+AS/108/79 : Ultra-steep spectrum radio sources (Roettgering+, 1994)J/A+AS/143/303 : Ultra steep spectrum radio sources catalog (De Breuck+ 2000)J/AJ/123/637 : Ultra-steep-spectrum radio sources (De Breuck +, 2002)J/MNRAS/355/20 : K magnitudes of 74MHz USS radio sources (Jarvis+, 2004)J/A+A/436/457 : Ultra-steep spectrum radio sources (Gopal-Krishna+, 2005)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/381/341https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/381/341http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/381/341https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/381/341https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/381/341http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/381/341GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/381/341/table3 (The MRCR-SUMSS USS sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/381/341/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/381/341/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/381/341/table3?GETtext/xml+votable180.050000true0.6305417-34.437250.005555555555555556Cone search capability for table J/MNRAS/381/341/table5 (Sources in the MRCR-SUMSS sample with likely optical identifications in SuperCOSMOS)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/381/341/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/381/341/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/381/341/table5?GETtext/xml+votable180.050000true4.4069167-36.78652780.0055555555555555566/16393-16394 16398 16400 16402 16404-16405 16411 16413 16429 16433 16435 16442 16458 16463 16466 16468 16472 16488 16514 16521-16523 16552 24585 24588 24606 24737 34552 35257 35262 35296 35309 35314 35319 35445 35447-35448 35531 35536 35539 35546 35551 35553 35557 35559-35561 35565 35569-35570 35573-35574 35587 35590 35598 35600 35604 35607-35609 35612 35625 35636 35646-35647 35656-35658 35672 35681 35685 35688 35713 35717 35721 35732 35887 35895-35896 35900 35902-35903 35911 35913 35921 35973 35977 35981-35982 36006 36010 38259 38266 38303 38330 38339 38344-38345 38348 38360 38380 38516-38518 38612 38660 38663 38666 38701 38711 38744 42675 42684-42685 42724 42728 42730 42736 43359 43379 43383 43423 43437 43443 43445 43461-43462 43467 43471 43474 43479 43490-43491 43497-43498 43502 43516 43631 43636 43638 43645 43702 43745 43782 43788 43793 43797 43815 44035-44036 44044 44046 44048-44049 44051 44055 44057 44064 44068 44070 44073 44075 44082 44084 44114 44120 46452 46454 46535 46541 46548 46563 46719 46799 46803-46804 46811-46812 46814 46829 46831 46833 46840 46861-46862 46874 46876-46877 46883 46886 46889-46890 46892 46894 46902 46909 46912 46936 47009 47016 47455 47576 47581 48136 48153 48162 48174 48183 48193 48195 48199 48205 48211 48224 48269 48271 48280https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/381/341?format=asciiRadiodefaultJ/MNRAS/381/341/table3The MRCR-SUMSS USS samplerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNVSSNVSS designation (JHHMMSS+DDMMSS)meta.id;meta.maincharprimaryf_NVSSFlag when associated data (G1)meta.codecharn_NVSS[abc] Note on NVSS (2)meta.notecharRAJ2000NVSS Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000NVSS Declination (J2000)pos.eq.dec;meta.mainS408Integrated flux density at 408MHzmJyphot.flux.density;em.radio.200-400MHzinte_S408rms uncertainty on 408MHzmJystat.errorintS843Integrated flux density at 843MHzmJyphot.flux.density;em.radio.750-1500MHzfloate_S843rms uncertainty on 843MHzmJystat.errorfloatS1384Integrated flux density at 1384MHzmJyphot.flux.density;em.radio.750-1500MHzfloate_S1384rms uncertainty on 1384MHzmJystat.errorfloatS1400Integrated flux density at 1400MHzmJyphot.flux.density;em.radio.750-1500MHzfloate_S1400rms uncertainty on 1400MHzmJystat.errorfloatS2368Integrated flux density at 2368MHzmJyphot.flux.density;em.radio.1500-3000MHzfloate_S2368rms uncertainty on 2368MHzmJystat.errorfloatalpha1Two-point observed-frame spectral index between 843 and 408MHzspect.indexfloate_alpha1rms uncertainty on alpha1stat.errorfloatalpha2Two-point observed-frame spectral index between 1400 and 843MHzspect.indexfloate_alpha2rms uncertainty on alpha2stat.errorfloatalpha3Two-point observed-frame spectral index between 2368 and 1384MHzspect.indexfloate_alpha3rms uncertainty on alpha3stat.errorfloatalpha? Five-point fit spectral index (3)spect.indexfloatnullablee_alpha? rms uncertainty on alphastat.error;pos.eq.rafloatnullablen_alpha[sf] (f)latten or (s)teepen spectrum (4)meta.notecharpNVSS? NVSS fractional linear polarization (5)%phys.polarization.linearfloatnullablee_pNVSS? rms uncertainty on pNVSS%stat.errorfloatnullablel_LASLimit flag on LASmeta.code.errorcharLASLargest angular size at 2368MHz (6)arcsecphys.angSize;em.radio.1500-3000MHz;stat.maxfloatLAS2? Second value of LASarcsecphys.angSizefloatnullablePA[-90/90]? Deconvolved position angle of the radio structure at 2368MHz, measured from the north to the east (7)degpos.posAngfloatnullablePA2[-90/90]? Second value of Position angledegpos.posAngfloatnullableMTypeRadio morphology at 2368MHz (8)src.morph.typecharMType2Second radio morphology at 2368MHz (8)meta.notecharNVSSdataDisplay the NVSS data (Condon et al. 1998, Cat. VIII/65)meta.ref.urlcharJ/MNRAS/381/341/table4ATCA properties of individual radio componentsn_NVSS[ab] Note on NVSS (2)meta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNVSSNVSS designation (JHHMMSS+DDMMSS)meta.id;meta.maincharm_NVSSMultiplicity index on NVSS (HT, ND, SD or WAT) (2)meta.code.multipcharf_NVSSFlag when associated data (G1)meta.codecharS1384c? 1384MHz integrated flux density of central component (3)mJyphot.flux.density;em.radio.750-1500MHzfloatnullableS1384? Total 1384MHz integrated flux density (4)mJyphot.flux.density;em.radio.750-1500MHzfloatnullableS1384n? 1384MHz integrated flux density of north lobe (3)mJyphot.flux.density;em.radio.750-1500MHzfloatnullablen_S1384n[(EW) ] Note on S1384n (4)meta.notecharS1384s? 1384MHz integrated flux density of south lobe (3)mJyphot.flux.density;em.radio.750-1500MHzfloatnullablen_S1384s[(EW) ] Note on S1384s (4)meta.notecharS2368c? 2368MHz integrated flux density of central component (3)mJyphot.flux.density;em.radio.1500-3000MHzfloatnullablen_S2368c[(EW) ] Note on S2368c (4)meta.notecharS2368? Total 2368MHz integrated flux density (4)mJyphot.flux.density;em.radio.1500-3000MHzfloatnullableS2368n? 2368MHz integrated flux density of north lobe (3)mJyphot.flux.density;em.radio.1500-3000MHzfloatnullablen_S2368n[(EW) ] Note on S2368n (4)meta.notecharS2368s? 2368MHz integrated flux density of south lobe (3)mJyphot.flux.density;em.radio.1500-3000MHzfloatnullablen_S2368s[(EW) ] Note on S2368s (4)meta.notecharalpha1? Two-point spectral index between 2368MHz and 1384MHz for central component (5)spect.indexfloatnullablealpha2? Two-point spectral index between 2368MHz and 1384MHz for north lobe (5)spect.indexfloatnullablealpha3? Two-point spectral index between 2368MHz and 1384MHz for south lobe (5)spect.indexfloatnullablel_p1384cLimit flag on p1384cmeta.code.errorcharp1384c? 1384MHz fractional linear polarization for the central component (6)%phys.polarization.linearfloatnullablee_p1384c? rms uncertainty on p1384c%stat.errorfloatnullablel_p1384nLimit flag on p1384nmeta.code.errorcharp1384n? 1384MHz fractional linear polarization for the north lobe component (6)%phys.polarization.linearfloatnullablee_p1384n? rms uncertainty on p1384n%stat.errorfloatnullablel_p1384sLimit flag on p1384smeta.code.errorcharp1384s? 1384MHz fractional linear polarization for the south lobe component (6)%phys.polarization.linearfloatnullablee_p1384s? rms uncertainty on p1384s%stat.errorfloatnullablel_p2368cLimit flag on p2368cmeta.code.errorcharp2368c? 2368MHz fractional linear polarization for the central component (6)%phys.polarization.linearfloatnullablee_p2368c? rms uncertainty on p2368c%stat.errorfloatnullablel_p2368nLimit flag on p2368nmeta.code.errorcharp2368n? 2368MHz fractional linear polarization for the north lobe component (6)%phys.polarization.linearfloatnullablen_p2368n[(E) ] (E) when data for eastern componentmeta.notechare_p2368n? rms uncertainty on p2368n%stat.errorfloatnullablel_p2368sLimit flag on p2368smeta.code.errorcharp2368s? 2368MHz fractional linear polarization for the south lobe component (6)%phys.polarization.linearfloatnullablen_p2368s[(W) ] (W) when data for weastern componentmeta.notechare_p2368s? rms uncertainty on p2368s%stat.errorfloatnullableRMC? Observed-frame Faraday rotation measure for the central components (7)rad.m**-2phys.polarization.rotMeasureintnullablee_RMC? rms uncertainty on RMCrad.m**-2stat.errorintnullableRMN? Observed-frame Faraday rotation measure for the north lobe components (7)rad.m**-2phys.polarization.rotMeasureintnullablee_RMN? rms uncertainty on RMNrad.m**-2stat.errorintnullableRMS? Observed-frame Faraday rotation measure for the south lobe components (7)rad.m**-2phys.polarization.rotMeasureintnullablee_RMS? rms uncertainty on RMSrad.m**-2stat.errorintnullableRM? Galactic rotation measure (8)rad.m**-2phys.polarization.rotMeasure;pos.galacticintnullableJ/MNRAS/381/341/table5Sources in the MRCR-SUMSS sample with likely optical identifications in SuperCOSMOSrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNVSSNVSS designation (JHHMMSS+DDMMSS)meta.id;meta.maincharNVSS2Second NVSS name when combined datameta.idcharRAJ2000Host galaxy Right ascension (J2000) (1)pos.eq.ra;meta.mainDEJ2000Host galaxy Declination (J2000) (1)pos.eq.dec;meta.mainl_BjmagLimit flag on Bjmagmeta.code.errorcharBjmagB_J_ magnitudemagphot.mag;em.opt.Bfloatl_RmagLimit flag on Rmagmeta.code.errorcharRmagR magnitudemagphot.mag;em.opt.RfloatJ/MNRAS/381/341/notesIndividual notesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNVSSNVSS designation (JHHMMSS+DDMMSS)meta.id;meta.maincharNoteText of the notemeta.notechar