J/MNRAS/508/2798ivo://CDS.VizieR/J/MNRAS/508/2798doi:10.26093/cds/vizier.75082798CDSSotnikova Y.Mikhailov A.Mufakharov T.Mingaliev M.Bursov N.,Semenova T.Stolyarov V.Udovitskiy R.Kudryashova A.Erkenov A.2024-08-21T20:18:45Z2022-03-04T15:47:44ZCDS support team

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

cds-question@unistra.frquasarsradio-sourcesWe present the radio properties of optically selected quasars with z>=3. The complete sample consists of 102 quasars with a flux density level S_1.4_>=100mJy in a declination range -35{deg}<=Dec.<=+49{deg}. The observations were obtained in 2017-2020 using the radio telescope RATAN-600. We measured flux densities at six frequencies 1.2, 2.3, 4.7, 8.2, 11.2, and 22GHz quasi-simultaneously with uncertainties of 9-31 per cent. The detection rate is 100, 89, and 46 per cent at 4.7, 11.2, and 22GHz, respectively. We have analysed the averaged radio spectra of the quasars based on the RATAN and literature data. We classify 46 per cent of radio spectra as peaked-spectrum, 24 per cent as flat, and none as ultra-steep spectra ({alpha}<=-1.1). The multifrequency data reveal that a peaked spectral shape (PS) is a common feature for bright high-redshift quasars. This indicates the dominance of bright compact core emission and the insignificant contribution of extended optically thin kpc-scale components in observed radio spectra. Using these new radio data, the radio loudness log R was estimated for 71 objects with a median value of 3.5, showing that the majority of the quasars are highly radio-loud with log R>2.5. We have not found any significant correlation between z and {alpha}. Several new megahertz- peaked spectrum (MPS) and gigahertz- peaked spectrum (GPS) candidates are suggested. Further studies of their variability and additional low-frequency observations are needed to classify them precisely.2021MNRAS.508.2798Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/508/2798CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)J/A+A/495/691 : Multifrequency catalogue of blazars Roma-BZCAT (Massaro+, 2009)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/508/2798https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/508/2798http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/508/2798https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/508/2798https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/508/2798http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/508/2798GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/508/2798/table1 (Parameters of 102 objects)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/508/2798/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/508/2798/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/508/2798/table1?GETtext/xml+votable180.050000true0.285958319.24286110.0055555555555555566/594 638 2112 2469 2820 3074 4114 4120 4263 4361 4446 4720 4947 5130 5170 5229 5362 5392 5470 6217 6469 6576 6790 6853 8218 8229 8255 8345 8525 8588 8627 8748 8912 9161 9334 9394 10328 10463 10558 10598 10603 10690 10694 10802 12471 12804 12888 13213 13314 14905 17326 17859 18164 18271 18644 18883 18988 19061 19673 19882 20156 20450 20657 21020 22298 23099 23257 23355 23548 25413 25677 25863 25990 26083 26816 27033 27302 27549 27608 28004 28369 29795 30836 31146 31355 31383 31444 31529 32410 32451 32746 34271 35741 35770 35952 36346 44724 46577 47050 47941 48610 487088.613890125444795e-25 1.4577353054677623e-23https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/508/2798?format=asciiRadiodefaultJ/MNRAS/508/2798/table1Parameters of 102 objectsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintzRedshift (1)src.redshiftfloatSimbadSimbad column added by the CDSmeta.ref.urlcharBlTypeBlazar type: FSRQ or blazar of uncertain type (2)src.classcharNVSSName (HHMMSS+DDMMSS, J2000)meta.id;meta.maincharS4.7Flux density at 4.7GHzJyphot.flux.density;em.radio.3-6GHzfloate_S4.7Flux density error at 4.7GHzJystat.errorfloatL4.7Radio luminosity at 4.7GHz (in 10^44^erg/s)1e+37Wphys.luminosity;em.radiofloate_L4.7Radio luminosity error1e+37Wstat.errorfloatlogR? logarithm of radio loudnessphot.flux;arith.ratiofloatnullablee_logR? error of logarithm of radio loudnessstat.errorfloatnullableAlowSpectral index in optical thick regionspect.indexfloate_AlowSpectral index errorstat.errorfloatAhighSpectral index in optical thin regionspect.indexfloate_AhighSpectral index errorstat.errorfloatSpTypeSpectral type: upturn, peaked, complex, flat, steep, invertedsrc.classchar_RAPositions mainly from NVSS (right ascension part)degpos.eq.ra;meta.main_DEPositions mainly from NVSS (declination part)degpos.eq.dec;meta.mainJ/MNRAS/508/2798/table2Flux densitiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordinte_S8? Error of flux density at 7.7/8.2GHzJystat.errorcharJDJulian datetime.epochintS22Flux density at 21.7/22GHzJyphot.flux.density;em.radio.12-30GHzchare_S22Error of flux density at 21.7/22GHzJystat.errorcharS11Flux density at 11.2GHzJyphot.flux.density;em.radio.6-12GHzchare_S11Error of flux density at 11.2GHzJystat.errorcharS8? Flux density at 7.7/8.2GHzJyphot.flux.density;em.radio.6-12GHzcharS4Flux density at 4.8GHzJyphot.flux.density;em.radio.3-6GHzchare_S4Error of flux density at 4.8GHzJystat.errorcharS2? Flux density at 2.3GHzJyphot.flux.density;em.radio.1500-3000MHzchare_S2? Error of flux density at 2.3GHzJystat.errorcharS1? Flux density at 1/1.3GHzJyphot.flux.density;em.radio.750-1500MHzchare_S1? Error of flux density at 1/1.3GHzJystat.errorcharNVSSName (HHMMSS+DDMMSS, J2000)meta.id;meta.mainchar