J/ApJ/771/105ivo://CDS.VizieR/J/ApJ/771/105doi:10.26093/cds/vizier.17710105CDSBernardi G.Greenhill L.J.Mitchell D.A.Ord S.M.Hazelton B.J.,Gaensler B.M.de Oliveira-Costa A.Morales M.F.Udaya Shankar N.,Subrahmanyan R.Wayth R.B.Lenc E.Williams C.L.Arcus W.Arora B.S.,Barnes D.G.Bowman J.D.Briggs F.H.Bunton J.D.Cappallo R.J.,Corey B.E.Deshpande A.deSouza L.Emrich D.Goeke R.Herne D.,Hewitt J.N.Johnston-Hollitt M.Kaplan D.Kasper J.C.Kincaid B.B.,Koenig R.Kratzenberg E.Lonsdale C.J.Lynch M.J.McWhirter S.R.,Morgan E.Oberoi D.Pathikulangara J.Prabu T.Remillard R.A.,Rogers A.E.E.Roshi A.Salah J.E.Sault R.J.Srivani K.S.Stevens J.,Tingay S.J.Waterson M.Webster R.L.Whitney A.R.Williams A.,Wyithe J.S.B.2017-10-09T13:34:13Z2015-02-18T08:11:12ZCDS support team

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

cds-question@unistra.frinterferometryradio-continuum-emissionWe present a Stokes I, Q and U survey at 189MHz with the Murchison Widefield Array 32 element prototype covering 2400deg^2^. The survey has a 15.6' angular resolution and achieves a noise level of 15mJy/beam. We demonstrate a novel interferometric data analysis that involves calibration of drift scan data, integration through the co-addition of warped snapshot images, and deconvolution of the point-spread function through forward modeling. We present a point source catalog down to a flux limit of 4Jy. We detect polarization from only one of the sources, PMN J0351-2744, at a level of 1.8%+/-0.4%, whereas the remaining sources have a polarization fraction below 2%. Compared to a reported average value of 7% at 1.4GHz, the polarization fraction of compact sources significantly decreases at low frequencies. We find a wealth of diffuse polarized emission across a large area of the survey with a maximum peak of ~13K, primarily with positive rotation measure values smaller than +10rad/m2. The small values observed indicate that the emission is likely to have a local origin (closer than a few hundred parsecs). There is a large sky area at {alpha}>=2^h^30^m^ where the diffuse polarized emission rms is fainter than 1K. Within this area of low Galactic polarization we characterize the foreground properties in a cold sky patch at ({alpha},{delta})=(4^h^,-27.6{deg}) in terms of three-dimensional power spectra.2013ApJ...771..105Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/771/105CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVIII/84 : A final non-redundant catalogue for 7C 151-MHz survey (Hales+ 2007)VIII/79 : The VLA Low-frequency Sky Survey at 74MHz (Cohen+ 2007)VIII/38 : The Parkes-MIT-NRAO 4.85GHz (PMN) Surveys (Griffith+ 1993-1996)VIII/35 : Radio Sources observed with Culgoora Circular Array (Slee 1995)VIII/24 : 6C Survey of Radio Sources - V. (Hales+ 1993)VIII/15 : Parkes Radio Sources Catalogue (PKSCAT90) (Wright+ 1990)J/MNRAS/426/3295 : Complete 150MHz GMRT source catalogue (Ghosh+, 2012)J/ApJ/755/47 : Murchison Widefield Array 110-200MHz obs. (Williams+ 2012)J/ApJ/734/L34 : 145MHz source measurements by PAPER (Jacobs+, 2011)J/ApJ/702/1230 : Rotation measure image of the sky (Taylor+, 2009)J/ApJ/642/868 : Rotation measures for 223 pulsars (Han+, 2006)J/ApJS/80/137 : Southern Extragalactic Radio Sources (Jones+, 1992)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/771/105https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/771/105http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/771/105https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/771/105https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/771/105http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/771/105GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/771/105/table2 (Catalog of sources brighter than 4Jy at 189MHz observed at the with the Murchison Widefield Array)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/771/105/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/771/105/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/771/105/table2?GETtext/xml+votable180.050000true308.9494167-34.90255560.0055555555555555566/16410 16427 16434 16454 16496 16509 16511 16512 16614 16655 16713 16722 16732 16760 16783 16787 16792 16805 16900 16901 16902 16904 16923 16934 16950 16993 16998 17003 17026 17052 17063 17158 18437 20529 20537 20541 20609 20614 20715 21049 21090 21126 21133 21134 21143 34293 34296 34303 34535 34545 34603 34616 34648 34650 34653 34665 34666 34715 34763 34785 35304 35568 35666 35685 35696 35712 35761 35768 35788 35792 35810 35812 35889 35934 35963 35996 36003 36014 36082 36085 36100 36130 36160 36178 36209 36378 36382 36391 36418 36431 36452 36509 36545 46573 46948 46989 46995 47006 47007 47008 47022 47080 48150 48159 48210 48228 48256 48278 48283 48311 48323 48324 48330 48337 48344 48398 48449 48463 48488 48493 48496 48523 48529 48530 48535 48558 48724 488991.252327119562319e-25 1.252327119562319e-25https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/771/105?format=asciiRadiodefaultJ/ApJ/771/105/table2Catalog of sources brighter than 4Jy at 189MHz observed at the with the Murchison Widefield ArraySimbadNameSimbad column added by the CDSmeta.idcharNameSource identifiermeta.id;meta.maincharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintf_Name[*] first measurements in the 100-200MHz bandmeta.codecharFlux[4/47.7] 189MHz fluxJyphot.flux.density;em.radio.100-200MHzfloate_Flux[0.3/2.6] Flux uncertainty (1)Jystat.error;phot.fluxfloatSEDPlot the spectrum with SPECFIND (Vollmer et al. 2009, Cat. VIII/85)meta.ref.urlcharNEDSimbad 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