J/A+A/573/A93ivo://CDS.VizieR/J/A+A/573/A93doi:10.26093/cds/vizier.35730093CDSVitale M.Fuhrmann L.Garcia-Marin M.Eckart A.Zuther J.Hopkins A.M.2015-04-07T13:46:14Z2015-03-11T14:53:18ZCDS support team

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

cds-question@unistra.frradio-galaxiesgalaxy-classification-systemsThe discovery of the M-{sigma} relation, the local galaxy bimodality, and the link between black-hole and host-galaxy properties have raised the question of whether active galactic nuclei (AGN) play a role in galaxy evolution. AGN feedback is one of the biggest observational challenges of modern extragalactic astrophysics. Several theoretical models implement AGN feedback to explain the observed galaxy luminosity function and, possibly, the color and morphological transformation of spiral galaxies into passive ellipticals. For understanding the importance of AGN feedback, a study of the AGN populations in the radio-optical domain is crucial. A mass sequence linking star-forming galaxies and AGN has already been noted in previous works, and it is now investigated as a possible evolutionary sequence. We observed a sample of 119 intermediate-redshift (0.04<=z<0.4) SDSS-FIRST radio emitters with the Effelsberg 100-m telescope at 4.85 and 10.45GHz and obtained spectral indices. The sample includes star-forming galaxies, composite galaxies (with mixed contribution to line emission from star formation and AGN activity), Seyferts, and low ionization narrow emission region (LINER) galaxies. With these sources we search for possible evidence of spectral evolution and a link between optical and radio emission in intermediate-redshift galaxies. We find indications of spectral index flattening in high-metallicity star-forming galaxies, composite galaxies, and Seyferts. This "flattening sequence" along the [NII]-based emission-line diagnostic diagram is consistent with the hardening of galaxy ionizing field, thanks to nuclear activity. After combining our data with FIRST measurements at 1.4GHz, we find that the three-point radio spectra of Seyferts and LINERs show substantial differences, which are attributable to small radio core components and larger (arcsecond sized) jet/lobe components, respectively. A visual inspection of FIRST images seems to confirm this hypothesis. Galaxies along this sequence are hypothesized to be transitioning from the active star-forming galaxies (blue cloud) to the passive elliptical galaxies (red sequence). This supports the suggestion that AGN both play a role in shutting down star formation and allow the transition from one galaxy class to the other.2015A&A...573A..93Vhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/573/A93CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/573/A93https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/573/A93http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/573/A93https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/573/A93https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/573/A93http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/573/A93GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/573/A93/tablea1 (Sources observed with the Effelsberg telescope at 10.45 and 4.85GHz)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/573/A93/tablea1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/573/A93/tablea1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/573/A93/tablea1?GETtext/xml+votable180.050000true204.380.59130.0055555555555555566/4166 4246 4276 4394 4512 4705 4708 4758 4807 4960 5005 5087 5225 5311 5491 5583 5920 6088 6436 6442 6451 6483 6515 6526 6532 7192 7266 7345 8212 8228 8248 8258 8299 8321 8414 8528 8576 8741 8897 8935 9019 9075 9083 9281 9767 9816 9981 9983 9991 10087 10327 10355 10535 10570 10579 10588 10748 10784 10815 10835 10975 11100 11136 11266 11355 11398 11426 11430 11512 17767 18075 18778 18857 22012 25907 25986 25995-25996 26027 26086 26095 26242-26243 26404 26469 26547 26620 26948 27051 27223 27360 27397 27468 27626 27654 27726 27733 27838 27853 27961 28036 28040 28092 28202 28270 28305 28350 28352 28360 28407 28472 28643 31377 31399 31423 31433 31599 490139.276497240453405e-25 6.924242574589622e-24https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/573/A93?format=asciiOpticalRadiodefaultJ/A+A/573/A93/tablea1Sources observed with the Effelsberg telescope at 10.45 and 4.85GHzrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintz[0/0.4] Redshiftsrc.redshiftfloatRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainF1.4Integrated flux density at 1.4GHzmJyphot.flux.density;em.radio.750-1500MHzfloatF10.45Flux density at 10.45GHzJyphot.flux.density;em.radio.6-12GHzfloate_F10.45rms uncertainty on F10.45GHzJystat.errorfloatF4.85Flux density at 4.85GHzJyphot.flux.density;em.radio.3-6GHzfloate_F4.85rms uncertainty on F4.85GHzJystat.errorfloatMTypeOptical morphology from SDSS images (1)src.morph.typecharRMorphRadio morphology from FIRST images (2)src.morph.paramcharActivityActivity type from NED (3)src.classcharNIId[LCS FS] Spectral classification according to the [NII]-based diagnostic diagram (4)meta.code.classcharSEDPlot the spectrum with SPECFIND (Vollmer et al. 2009, Cat. VIII/85)meta.ref.urlchar