MALS SALT-NOT survey of MIR-selected powerful radio-bright AGN at 0<z<3.5

Abstract

We present results of an optical spectroscopic survey using SALT and NOT to build a WISE mid-infrared color-based, dust-unbiased sample of powerful radio-bright ($>$200 mJy at 1.4 GHz) 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 ($\Delta i$=0.6 mag) and redder ($\Delta (g-i)$=0.2 mag) 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 $z<0.5$ are galaxies without strong nuclear emission, and 10% at $z>1.9$, have emission line ratios similar to radio galaxies. The farthest NLAGN in our sample is M1513$-$2524 ($z_{em}=3.132$), and the largest (size$\sim$330 kpc) is M0909$-$3133 ($z_{em}=0.884$). We discuss in detail 110 AGN at $1.9<z<3.5$. Despite representing the radio loudest quasars (median $R$=3685), their Eddington ratios are similar to the SDSS quasars having lower $R$. We detect 4 CIV BALQSOs, all among AGN with least $R$, and highest black hole masses and Eddington ratios. The BAL detection rate ($4_{-2}^{+3}$%) is consistent with that seen in extremely powerful ($L_{1.4GHz}>10^{25}$ WHz${}^{-1}$) quasars. Using optical light-curves, radio polarization and $\gamma$-ray detections, we identify 7 high-probability BL Lacs. We also summarize the full MALS footprint to search for HI 21-cm and OH 18-cm lines at $z<2$.

arXiv comment62 pages, 15 figures and 3 tables; accepted in ApJ (updated the redshift of M1312-2026 to z=0.977)

References in corpus (68)

• The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
• Unified Schemes for Radio-Loud Active Galactic Nuclei
• Observational Evidence of AGN Feedback
• Reverberation Measurements for 17 Quasars and the Size-Mass-Luminosity Relations in Active Galactic Nuclei
• A Catalog of Quasar Properties from SDSS DR7
• Determining Central Black Hole Masses in Distant Active Galaxies and Quasars. II. Improved Optical and UV Scaling Relationships
• The Co-Evolution of Galaxies and Supermassive Black Holes: Insights from Surveys of the Contemporary Universe
• The Zwicky Transient Facility: Data Processing, Products, and Archive
• On characterising the variability properties of X-ray light curves from active galaxies
• Spectral Energy Distributions and Multiwavelength Selection of Type 1 Quasars
• Spectroscopic Target Selection in the Sloan Digital Sky Survey: The Quasar Sample
• Mid-Infrared Selection of Active Galaxies
• SUMSS: A Wide-Field Radio Imaging Survey of the Southern Sky. II. The Source Catalogue
• Mid-Infrared Selection of AGN with the Wide-Field Infrared Survey Explorer. I. Characterizing WISE-Selected AGN in COSMOS
• Damped Lyman alpha Systems
• Obscured and unobscured active galactic nuclei in the Spitzer Space Telescope First Look Survey
• Active Galactic Nuclei: what's in a name?
• Supermassive Black Holes in Active Galactic Nuclei. II. Calibration of the M-sigma Relationship for AGNs
• Radio-Loudness of Active Galactic Nuclei: Observational Facts and Theoretical Implications
• Obscured Active Galactic Nuclei
• Roma-BZCAT: A multifrequency catalogue of Blazars
• Reverberation Mapping Measurements of Black Hole Masses in Six Local Seyfert Galaxies
• Using the Bright Ultra-Hard XMM-Newton Survey to define an IR selection of luminous AGN based on WISE colours
• Spitzer Quasar and ULIRG Evolution Study (QUEST): II. The Spectral Energy Distributions of Palomar-Green Quasars
• Low Resolution Spectral Templates For AGNs and Galaxies From 0.03 -- 30 microns
• Narrow-line region gas kinematics of 24,264 optically-selected AGN: the radio connection
• Evolution of the cosmological mass density of neutral gas from Sloan Digital Sky Survey II - Data Release 7
• The Rapid ASKAP Continuum Survey I: Design and First Results
• The VLT-UVES survey for molecular hydrogen in high-redshift damped Lyman-alpha systems
• On Black Hole Masses and Radio Loudness in AGN
• Properties of Radio-Selected Broad Absorption-Line Quasars from the FIRST Survey
• The WISE AGN Catalog
• Molecular hydrogen in high-redshift Damped Lyman-alpha systems: The VLT/UVES database
• The CORALS Survey I: New Estimates of the Number Density and Gas Content of Damped Lyman Alpha Systems Free from Dust Bias
• Type 2 AGNs with Double-Peaked [O III] Lines: Narrow Line Region Kinematics or Merging Supermassive Black Hole Pairs?
• Pan-STARRS Pixel Processing: Detrending, Warping, Stacking
• Magnetic flux paradigm for radio-loudness of AGN
• The Properties of the Radio-Selected 1Jy Sample of BL Lacertae Objects
• CIV Emission Line Properties and Systematic Trends in Quasar Black Hole Mass Estimates
• Fermi Large Area Telescope Fourth Source Catalog Data Release 2
• Dust-reddening and gravitational lensing of SDSS QSOs due to foreground damped Lyman-alpha systems
• 2WHSP: A catalog of HE and VHE gamma-ray blazars and blazar candidates
• Deep Learning of Quasar Spectra to Discover and Characterize Damped Lya Systems
• Buried AGNs in Advanced Mergers:Mid-infrared color selection as a dual AGN finder
• Ionized Gas in Damped Lyman Alpha Protogalaxies: I. Model-Independent Inferences From Kinematic Data
• Two new catalogs of blazar candidates in the WISE infrared sky
• Dependence of the BALQSO fraction on Radio Luminosity
• Search for cold gas in z>2 damped Lyman-alpha systems: 21-cm and H_2 absorption
• Radio-loud AGNs at high redshifts and the cosmic microwave background
• VLT/UVES observations of extremely strong intervening damped Lyman-alpha systems: Molecular hydrogen and excited carbon, oxygen and silicon at log N(HI)=22.4
• Constraining the H${}_2$ column density distribution at z$\sim$3 from composite DLA spectra
• Dust Biasing of Damped Lyman Alpha Systems: a Bayesian Analysis
• An HST/COS survey of molecular hydrogen in DLAs & sub-DLAs at z < 1: Molecular fraction and excitation temperature
• Blind HI and OH absorption line search: first results with MALS and uGMRT processed using ARTIP
• A Catalog of Host Galaxies for WISE-Selected AGN: Connecting Host Properties with Nuclear Activity and Identifying Contaminants
• The effect of dust bias on the census of neutral gas and metals in the high-redshift Universe due to SDSS-II quasar colour selection
• Searching for Dust Reddening in SDSS Spectra with Damped Lyman $\alpha${} Systems
• X-ray Absorption Towards The Einstein Ring Source PKS1830-211
• Outflowing material in the CSS quasar 3C48: evidence of jet-cloud interaction?
• PKS1830-211: OH and HI at z=0.89 and the first MeerKAT UHF spectrum
• The MeerKAT Absorption Line Survey (MALS)
• A search for damped Lyman-alpha systems towards radio-loud quasars I: The optical survey
• MALS-NOT: Identifying Radio-Bright Quasars for the MeerKAT Absorption Line Survey
• The Cosmic Ultraviolet Baryon Survey (CUBS) II: Discovery of an H${}_2$-Bearing DLA in the Vicinity of an Early-Type Galaxy at z = 0.576
• Evolution of cold gas at 2<z<5: a blind search for HI and OH absorption lines towards mid-infrared color selected radio-loud AGNs
• Spatially resolved Lyman-$\alpha$ emission around radio bright quasars
• Evidence for Late-Time Feedback from the Discovery of Multiphase Gas in a Massive Elliptical at $z=0.4$
• Lyman-$\alpha$ emission from a WISE-selected optically faint powerful radio galaxy M151304.72-252439.7 at $z$ = 3.132

Cited by in corpus (5)

• Proximate molecular quasar absorbers: Chemical enrichment and kinematics of the neutral gas
• The MeerKAT Absorption Line Survey: Homogeneous continuum catalogues towards a measurement of the cosmic radio dipole
• Discovery of Hydrogen Radio Recombination Lines at z=0.89 towards PKS 1830-211
• The MeerKAT Absorption Line Survey (MALS) data release 3: Cold atomic gas associated with the Milky Way
• Dim cores of radio-bright AGN jets: VLBI and Gaia astrometry pinpoint different parsec-scale features