J/A+A/674/A119ivo://CDS.VizieR/J/A+A/674/A119doi:10.26093/cds/vizier.36740119CDSSnidaric I.Jelic V.Mevius M.Brentjens M.Erceg A.Shimwell T.W.,Piras S.Horellou C.Sabater J.Best P.N.Bracco A.Ceraj L.,Haverkorn M.O'Sullivan S.P.Turic L.Vacca V.2024-11-06T20:04:24Z2023-06-12T08:00:29ZCDS support team

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

cds-question@unistra.frmilky-way-galaxypolarimetryradio-continuum-emissionWe present the first deep polarimetric study of Galactic synchrotron emission at low radio frequencies. Our study is based on 21 observations of the European Large Area Infrared Space Observatory Survey-North 1 (ELAIS-N1) field using the Low-Frequency Array (LOFAR) at frequencies from 114.9 to 177.4MHz. These data are a part of the LOFAR Two-metre Sky Survey (LoTTS) Deep Fields Data Release 1. We used very low-resolution (4.3') Stokes QU data cubes of this release. We applied rotation measure (RM) synthesis to decompose the distribution of polarised structures in Faraday depth, and cross-correlation RM synthesis to align different observations in Faraday depth. We stacked images of about 150 hours of the ELAIS-N1 observations to produce the deepest Faraday cube at low radio frequencies to date, tailored to studies of Galactic synchrotron emission and the intervening magneto-ionic interstellar medium. This Faraday cube covers 36 deg^2^ of the sky and has a noise of 27uJy/PSF/RMSF in polarised intensity. This is an improvement in noise by a factor of approximately the square root of the number of stacked data cubes (sqrt(20)), as expected, compared to the one in a single data cube based on five-to-eight-hour observations. We detect a faint component of diffuse polarised emission in the stacked cube, which was not detected previously. Additionally, we verify the reliability of the ionospheric Faraday rotation corrections estimated from the satellite-based total electron content measurements to be of 0.05rad/m^2^. We also demonstrate that diffuse polarised emission itself can be used to account for the relative ionospheric Faraday rotation corrections with respect to a reference observation.2023A&A...674A.119Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/674/A119CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/MNRAS/371/1891 : GOODS ELAIS-N1 24um flux densities (Rodighiero+, 2006)J/ApJ/666/201 : Radio polarimetry of the ELAIS N1 field (Taylor+, 2007)J/MNRAS/383/75 : Deep 610MHz survey of ELAIS-N1 sources (Garn+, 2008)J/MNRAS/395/269 : ELAIS-N1 field 325MHz observations (Sirothia+, 2009)J/MNRAS/472/4259 : IRAC Dark Field, ELAIS-N1 & ADF-S galaxies (Davidge+, 2017)J/MNRAS/490/243 : ELAIS N1 field uGMRT 400MHz source catalogJ/A+A/648/A2 : LOFAR Two-metre Sky Survey Deep Fields DR1 (Sabater+, 2021)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/674/A119https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/674/A119http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/674/A119https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/674/A119https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/674/A119http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/674/A119GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/674/A119/list (Informations of Faraday cube)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/674/A119/list?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/674/A119/list?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/674/A119/list?GETtext/xml+votable180.050000true242.7555.00.0055555555555555566/10155https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/674/A119?format=asciiRadiodefaultJ/A+A/674/A119/listInformations of Faraday cuberecnoRecord 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.numberintNzNumber of slicesmeta.numberintObs.dateObservation datestime.epoch;obsnullablesizeSize of FITS fileKibytephys.size;meta.fitsintFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharTitleTitle of the FITS filemeta.title;meta.fitschar