J/A+A/648/A104ivo://CDS.VizieR/J/A+A/648/A104doi:10.26093/cds/vizier.36480104CDSde Gasperin F.Williams W.L.Best P.Brueggen M.Brunetti G.,Cuciti V.Dijkema T.J.Hardcastle M.J.Norden M.J.Offringa A.,Shimwell T.van Weeren R.Bomans D.Bonafede A.Botteon A.,Callingham J.R.Cassano R.Chyzy K.T.Emig K.L.Edler H.Haverkorn M.,Heald G.Heesen V.Iacobelli M.Intema H.T.Kadler M.Malek K.,Mevius M.Miley G.Mingo B.Morabito L.K.Sabater J.Morganti R.,Orru E.Pizzo R.Prandoni I.Shulevski A.Tasse C.Vaccari M.,Zarka P.Roettgering H.2021-12-08T20:03:10Z2021-04-22T07:35:51ZCDS support team

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

cds-question@unistra.frsurveysradio-sourcesradio-continuum-emissionLOFAR is the only radio telescope that is presently capable of high-sensitivity, high-resolution (i.e. <1mJy/b and <15") observations at ultra-low frequencies (<100MHz). To utilise these capabilities, the LOFAR Surveys Key Science Project is undertaking a large survey to cover the entire northern sky with Low Band Antenna (LBA) observations. The LOFAR LBA Sky Survey (LoLSS) aims to cover the entire northern sky with 3170 pointings in the frequency range 42-66MHz, at a resolution of 15-arcsec and at a sensitivity of 1mJy/beam (1{sigma}. Here we outline the survey strategy, the observational status, the current calibration techniques, and briefly describe several scientific motivations. We also describe the preliminary public data release. The preliminary images were produced using a fully automated pipeline that aims to correct all direction-independent effects in the data. Whilst the direction-dependent effects, such as those from the ionosphere, are not yet corrected, the images presented in this work are still 10 times more sensitive than previous surveys available at these low frequencies. The preliminary data release covers 740deg^2^ around the HETDEX spring field region at a resolution of 47" with a median noise level of 5mJy/beam. The images and the catalogue with 25247 sources are publicly released. We demonstrate that the system is capable of reaching an rms noise of 1mJy/beam and the resolution of 15" once direction-dependent effects are corrected for. LoLSS will provide the ultra-low-frequency information for hundreds of thousands of radio sources, providing critical spectral information and producing a unique dataset that can be used for a wide range of science topics such as: the search for high redshift galaxies and quasars, the study of the magnetosphere of exoplanets, and the detection of the oldest populations of cosmic-rays in galaxies, clusters of galaxies, and from AGN activity.2021A&A...648A.104Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/648/A104CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/648/A104https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/648/A104http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/648/A104https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/648/A104https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/648/A104http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/648/A104GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/648/A104/lolssv3 (LOFAR LBA Sky Survey preliminary release catalog)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/648/A104/lolssv3?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/648/A104/lolssv3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/648/A104/lolssv3?GETtext/xml+votable180.050000true160.4570676357746.562658978820.005555555555555556Cone search capability for table J/A+A/648/A104/list (Information on fits image)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/648/A104/list?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/648/A104/list?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/648/A104/list?GETtext/xml+votable180.050000true200.8919355.352460.0055555555555555563/93 173-174 178 4/349-351 369 380-381 622 669-671 685-687 689-691 700-702 705-710 716 736-737 5/1373-1375 1389 1391 1393 1395 1485 1529 2479 2483 2486 2492 2494-2495 2655 2671 2674-2675 2719 2735 2739 2753 2755 2819 2844 2846 2868 2870 2872-2874 2880 2952-2954 2956 2960 2976 6/5471 5491 5535 5555 5561-5563 5571 5577-5579 5893 5895 5901 5903 5936-5937 5948-5949 5951 6037 6112-6113 6115 6121 6124-6125 6128-6130 6132 6136 9909-9911 9913-9915 9926-9927 9929-9931 9936 9938-9939 9974-9975 10154 10613-10615 10617-10619 10655 10671 10677-10679 10681-10683 10693-10695 10847 10863 10867 10869-10871 10873-10875 10911 10931 10933-10935 10937-10939 10949-10951 10953-10955 11017-11019 11248-11250 11269-11271 11273-11275 11380-11382 11500-11502 11504-11506 11512 11528 11530 11820-11822 11828 11832 11844 11848 11908 11912https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/648/A104?format=asciiRadiodefaultJ/A+A/648/A104/lolssv3LOFAR LBA Sky Survey preliminary release catalogrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameSource ID (LOLpJHHMMSS.s+DDMMSS)meta.id;meta.maincharRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainindexede_RAJ2000Error on the Right ascensionarcsecstat.error;pos.eq.radoubleDEJ2000Declination (J2000)degpos.eq.dec;meta.mainindexede_DEJ2000Error on the Declinationarcsecstat.error;pos.eq.decdoubleTotalFluxIntegrated flux densitymJyphot.flux.density;em.radiodoublee_TotalFluxError on the integrated flux densitymJystat.errordoublePeakFluxPeak brightness, affected by smearingmJy/beamphot.flux.density;em.radiodoublee_PeakFluxError on the peak brightnessmJy/beamstat.errordoubleMajSource size, major axisarcsecphys.angSizedoublee_MajError on the major axisarcsecstat.errordoubleMinSource size, minor axisarcsecphys.angSize;srcdoublee_MinError on the minor axisarcsecstat.error;stat.mindoublePAPosition angledegpos.posAngdoublee_PAError on the position angledegstat.errordoubleDCMajDeconvolved source size, major axisarcsecphys.angSizedoublee_DCMajError on the deconvolved major axisarcsecstat.errordoubleDCMinDeconvolved source size, minor axisarcsecphys.angSize;srcdoublee_DCMinError on the deconvolved minor axisarcsecstat.errordoubleDCPADeconvolved position angledegpos.posAngdoublee_DCPAError on the deconvolved position angledegstat.errordoubleIslrmsLocal rms noisemJy/beamstat.errordoubleSCode[CMS] Source code (1)meta.codecharJ/A+A/648/A104/listInformation on fits imagerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right Ascension of center (J2000)degpos.eq.ra;meta.mainDEJ2000Declination of center (J2000)degpos.eq.dec;meta.mainNxNumber of pixels along X-axismeta.numberintNyNumber of pixels along Y-axismeta.numberintsizeSize of FITS fileKibytephys.size;meta.fitsintFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharTitleTitle of the FITS filemeta.title;meta.fitschar