J/A+A/363/887ivo://CDS.VizieR/J/A+A/363/887doi:10.26093/cds/vizier.33630887CDSDallacasa D.Stanghellini C.Centonza M.Fanti R.2001-05-19T15:26:53Z2001-05-19T15:26:48ZCDS support team

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

cds-question@unistra.frradio-galaxiesquasarsradio-astronomyHere we present a sample of sources with convex radio spectra peaking at frequencies above a few GHz. We call these radio sources High Frequency Peakers (HFPs). This sample extends to higher turnover frequencies than the samples of Compact Steep Spectrum (CSS) and GHz Peaked Spectrum (GPS) radio sources. HFPs are rare due to the strong bias against them caused by their turnover occurring at frequencies about one order of magnitude higher than in CSS-GPS samples. he sample has been selected by a comparison between the Green Bank survey (87GB) at 4.9 GHz and the NRAO VLA Sky Survey (NVSS) at 1.4 GHz. Then the candidates have been observed with the VLA at 1.365, 1.665, 4.535, 4.985, 8.085, 8.485, 14.96 and 22.46 GHz in order to derive a simultaneous radio spectrum, and remove variable sources from the sample. The final list of genuine HFP sources consists of 55 objects with flux density exceeding 300 mJy at 4.9 GHz at the time of the 87GB observation. Optical identifications are available for 29 of them; 24 are high redshift quasars, 3 are galaxies (one of them has indeed broad lines in the optical spectrum) and 2 are BL Lac objects. The remaining sources are mostly empty fields (17) on the digitised POSS or have uncertain classification (9).2000A&A...363..887Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/363/887CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)VIII/40 : GB6 catalog of radio sources (Gregory+ 1996)VIII/60 : Interferometer phase calibration sources (Patnaik+ 1998)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/363/887https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/363/887http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/363/887https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/363/887https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/363/887http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/363/887GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/363/887/table1 (Candidates observed with the VLA)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/363/887/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/363/887/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/363/887/table1?GETtext/xml+votable180.050000true0.830583321.49569440.0055555555555555566/465 550 991 1019 1225 1576 1909 2089 2179 2631 2817 4155 5458 5630 5767 6381 6755 6815 6853 7119 7129 7570 7623 7653 7857 8199 8220 8252 8365 8718 8912 9202 9681 9720 10213 10321 10422 10798 10921 11024 11041 11216 11430 11552 11594 11640 11669 11686 11808 12301 12352 12471 12611 12625 12896 13153 13352 13359 13572 13585 13731 14879 14905 15819 16027 17857 18871 18932 19101 19287 19367 19483 19537 19549 19748 20228 21960 21972 22298 23015 23127 23215 23226 23720 24084 26107 27433 27436 27446 27464 30171 31222 31529 31663 31666 31894 31930 32160 32247 32362 32374 32764https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/363/887?format=asciiRadiodefaultJ/A+A/363/887/table1Candidates observed with the VLAB1950B1950 namemeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameName based on J2000 coordinates (HHMM+DDMM)meta.id;meta.maincharRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainNVSSNVSS (Cat. <VIII/65>) flux density at 1.4GHzmJyphot.flux.density;em.radio.750-1500MHzfloat87GB87GB (Cat. <VIII/40>) flux density at 4.85GHzmJyphot.flux.density;em.radio.3-6GHzintJVAS? JVAS (Cat. <VIII/60>) flux density at 8.4GHzmJyphot.flux.density;em.radio.6-12GHzintnullableSp-IndexSpectral index between the NVSS and the 87GB (S{prop.to}{nu}^-{alpha}^)spect.indexfloatSampleSource in other relevant samples (1)meta.idcharIDOptical identification (2)src.classcharmag? Magnitude from NED database (not all in the same band)magphot.magfloatnullableu_mag[?] Uncertainty flag on magmeta.code.errorcharz? Redshift from NED databasesrc.redshiftdoublenullableu_z[?] Uncertainty flag on zmeta.code.errorchar