J/A+A/693/L2ivo://CDS.VizieR/J/A+A/693/L2doi:10.26093/cds/vizier.36939002CDSPerger K.Fogasy J.Frey S.Gabanyi K.E.2025-02-24T20:02:26Z2024-12-23T10:06:04ZCDS support team

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

cds-question@unistra.frradio-sourcesactive-galactic-nucleiredshiftedTo investigate the radio properties of the recently found high-redshift population, we collected a sample of 919 little red dots (LRDs) from the literature. By cross-matching their coordinates with the radio catalogues based on the first- and second-epoch observations of the Very Large Array Sky Survey (VLASS) and the Faint Images of the Radio Sky at Twenty-centimeters (FIRST) survey, we found no radio counterparts coinciding with any of the LRDs. To uncover possible sub-mJy level weak radio emission, we performed mean and median image stacking analyses of empty-field 'Quick Look' VLASS and FIRST image cutouts centred on the LRD positions. We found no radio emission above 3 sigma noise levels (~11 and ~18uJy/beam for the VLASS and FIRST maps, respectively) in either of the stacked images for the LRD sample, while the noise levels of the single-epoch images are comparable to those found earlier in the stacking of high-redshift radio-quiet active galactic nuclei (AGNs). The non-detection of radio emission in LRDs suggests these sources host weaker (or no) radio AGNs.2025A&A...693L...2Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/693/L2CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/693/L2https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/693/L2http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/693/L2https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/693/L2https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/693/L2http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/693/L2GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/693/L2/stacked (List of the selected little red dots (LRDs))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/693/L2/stacked?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/693/L2/stacked?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/693/L2/stacked?GETtext/xml+votable180.050000true3.444851-30.3263620.0055555555555555565/6814 6/2187 5630 7904 11252 11425 16486 17679 17688 17690 18242 27124 35935https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/693/L2?format=asciiRadiodefaultJ/A+A/693/L2/stackedList of the selected little red dots (LRDs)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameSource identifier from the discovery papermeta.id;meta.maincharRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainzspec? Spectroscopic redshiftsrc.redshiftdoublenullablezphot? Photometric redshiftsrc.redshiftfloatnullableRefBibcodemeta.bib.bibcodecharNotesNotesmeta.notechar