MALS SALT-NOT survey of MIR-selected AGN at z<3.5

We present results of an optical spectroscopic survey using SALT and the Nordic Optical Telescope to build a Wide-field Infrared Survey Explorer mid-infrared color-based, dust-unbiased sample of powerful radio-bright (>200mJy at 1.4GHz) active galactic nuclei (AGN) for the MeerKAT Absorption Line Survey (MALS). Our sample has 250 AGN (median z=1.8) showing emission lines, 26 with no emission lines, and 27 without optical counterparts. Overall, our sample is fainter ({Delta}i=0.6mag) and redder ({Delta}(g-i)=0.2mag) than radio-selected quasars, and representative of fainter quasar population detected in optical surveys. About 20% of the sources are narrow-line AGN (NLAGN)-65% of these, at z1.9, have emission line ratios similar to radio galaxies. The farthest NLAGN in our sample is M1513-2524 (z_em_=3.132), and the largest radio source (size ~330kpc) is M0909-3133 (z_em_=0.884). We discuss in detail 110 AGN at 1.9<z10^25^W/Hz) quasars. Using optical light curves, radio polarization, and {gamma}-ray detections, we identify seven high-probability BL Lacertae objects. We also summarize the full MALS footprint to search for HI 21cm and OH 18cm lines at z<2.

Cone search capability for table J/ApJ/929/108/table1 (*radio sources for the uGMRT survey)

Identifier
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/ApJ/929/108
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/929/108
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/929/108
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/ApJ/929/108
Provenance
Creator Gupta N.; Shukla G.; Srianand R.; Krogager J.-K.; Noterdaeme P.,Baker A.J.; Combes F.; Fynbo J.P.U.; Momjian E.; Hilton M.; Hussain T.,Moodley K.; Petitjean P.; Chen H.-W.; Deka P.; Dutta R.; Jose J.,Jozsa G.I.G.; Kaski C.; Klockner H.-R.; Knowles K.; Sikhosana S.,Wagenveld J.
Publisher CDS
Publication Year 2024
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Cosmology; Galactic and extragalactic Astronomy; High Energy Astrophysics; Interdisciplinary Astronomy; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy