J/A+A/664/A83ivo://CDS.VizieR/J/A+A/664/A83doi:10.26093/cds/vizier.36640083CDSHeesen V.Staffehl M.Basu A.Beck R.Stein M.Tabatabaei F.S.,Hardcastle M.J.Chyzy K.T.Shimwell T.W.Adebahr B.Beswick R.,Bomans D.J.Botteon A.Brinks E.Brueggen M.Dettmar R.-J.Drabent A.,de Gasperin F.Guerkan G.Heald G.H.Horellou C.Nikiel-Wroczynski B.,Paladino R.Piotrowska J.Roettgering H.J.A.Smith D.J.B.Tasse C.2022-09-30T23:29:14Z2022-08-08T08:44:35ZCDS support team

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

cds-question@unistra.frsurveysradio-continuum-emissiongalaxiesCosmic rays and magnetic fields are key ingredients in galaxy evolution, regulating both stellar feedback and star formation. Their properties can be studied with low-frequency radio continuum observations, free from thermal contamination. We define a sample of 76 nearby (<30Mpc) galaxies, with rich ancillary data in the radio continuum and infrared from the CHANG-ES and KINGFISH surveys, which will be observed with the LOFAR Two-metre Sky Survey (LoTSS) at 144 MHz. Methods. We present maps for 45 of them as part of the LoTSS data release 2 (LoTSS-DR2), where we measure integrated flux densities and study integrated and spatially resolved radio spectral indices. We investigate the radio-SFR relation, using star-formation rates (SFR) from total infrared and H{alpha}+24-um emission. The radio-SFR relation at 144 MHz is clearly super-linear with L144{prop.to}=SFR1.4-1.5. The mean integrated radio spectral index between 144 and ~1400MHz is <{alpha}>=-0.56+/-0.14, in agreement with the injection spectral index for cosmic ray electrons (CRE). However, the radio spectral index maps show a variation of spectral indices with flatter spectra associated with star-forming regions and steeper spectra in galaxy outskirts and, in particular, in extra-planar regions. We found that galaxies with high star-formation rates (SFR) have steeper radio spectra; we find similar correlations with galaxy size, mass, and rotation speed. Galaxies that are larger and more massive are better electron calorimeters, meaning that the CRE lose a higher fraction of their energy within the galaxies. This explains the super-linear radio-SFR relation, with more massive, star-forming galaxies being radio bright. We propose a semi-calorimetric radio-SFR relation, which employs the galaxy mass as a proxy for the calorimetric efficiency.2022A&A...664A..83Hhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/664/A83CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/659/A1 : LOFAR Two-metre Sky Survey (LoTSS) DR2 (Shimwell+, 2022)J/A+A/660/A78 : LoTSS-DR2 sample overview release (Botteon+, 2022)J/ApJS/257/30 : BL Lac morphologies with LoTSS-DR2 144MHz data (Mooney+, 2021)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/664/A83https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/664/A83http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/664/A83https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/664/A83https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/664/A83http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/664/A83GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/664/A83/flux (Integrated 144-MHz flux densities of the 45 galaxies in LoTSS-DR2)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/664/A83/flux?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/664/A83/flux?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/664/A83/flux?GETtext/xml+votable180.050000true23.4620419430.660221940.005555555555555556Cone search capability for table J/A+A/664/A83/list (List of fits maps)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/664/A83/list?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/664/A83/list?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/664/A83/list?GETtext/xml+votable180.050000true158.1335854.400560.005555555555555556Associated datahttps://cdsarc.cds.unistra.fr/assocdata/?obs_collection=J/A+A/664/A836/764 2155 2316 2320 2409 5067 5181 5469 5492 5504 5587 5639 5715 5751 5799 5995 6037 6042 7241 7424 7584 7602 7604 7606 10073 10475 10674 10751 10761 10841 10856 10888 10901 10911 10979 10986 11000 11026-11027 11263 11375 11434 11457 13522 28123 28496 286319.54153977050123e-26 9.54153977050123e-26https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/664/A83?format=asciiRadiodefaultJ/A+A/664/A83/fluxIntegrated 144-MHz flux densities of the 45 galaxies in LoTSS-DR2SimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameCatalog name of the galaxymeta.id;meta.maincharRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainaSemi-major axis of the integration ellipse for the 20" maparcminphys.angSizefloatbSemi-minor axis of the integration ellipse for the 20" maparcminphys.angSize.sminAxisfloatS144Integrated radio flux density at 144MHzJyphot.flux.density;em.radio.100-200MHzfloate_S144Error of flux densityJystat.errorfloatmapsDisplay the map listmeta.ref.urlcharJ/A+A/664/A83/listList of fits mapsTitleTitle of the FITS filemeta.title;meta.fitscharAssocDataAssociated Data web pagemeta.ref.urlcharNameCatalog name of the galaxymeta.id;meta.maincharFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharrecnoRecord 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.numberintObs.dateObservation datestime.epoch;obsnullablesizeSize of FITS fileKibytephys.size;meta.fitsint