LRD host galaxies show average metallicity 0.08 Z_sun with narrow stable range, challenging pristine-gas formation models while ruling out typical local AGN.
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E., & Ho, L
31 Pith papers cite this work, alongside 764 external citations. Polarity classification is still indexing.
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abstract
It has been established that virial masses for black holes in low-redshift active galaxies can be estimated from measurements of the optical continuum strength and the width of the broad Hbeta line. Under various circumstances, however, both of these quantities can be challenging to measure or can be subject to large systematic uncertainties. To mitigate these difficulties, we present a new method for estimating black hole masses. From analysis of a new sample of broad-line active galactic nuclei, we find that Halpha luminosity scales almost linearly with optical continuum luminosity and that a strong correlation exists between Halpha and Hbeta line widths. These two empirical correlations allow us to translate the standard virial mass system to a new one based solely on observations of the broad Halpha emission line.
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The survey identifies 27 low-redshift LRDs with compact morphology, V-shaped continua, broad Balmer lines with extreme decrements, and ubiquitous outflows, matching high-z counterparts and yielding a number density lower limit of 7.5e-10 cMpc^-3.
Targeted PTA searches for CWs from 114 AGN in NANOGrav 15 yr data yield no detections, factor-of-two tighter limits than all-sky searches, and updated constraints ruling out part of the parameter space for a binary in 3C 66B.
Confirmation of 77 new heavily reddened quasars at 1.5 < z < 3.9 with high luminosities and extinctions, showing they are deficient in hot and warm dust relative to blue quasars and supporting a blow-out feedback phase.
A changing-look AGN exhibits a rapid accretion-driven spectral transition with broad-line region temperatures of approximately 11,800 K measured via Boltzmann plots and stable black hole mass estimates of 5 times 10 to the 7 solar masses across epochs.
Little Red Dots show soft ionizing spectra consistent with massive stars, based on high H-alpha EWs and low HeII/H-beta ratios that rule out hard AGN spectra via Cloudy modeling.
LRDs at z~3-7 exhibit an L_Hα,broad-L_bol scaling relation enhanced by a factor of ~40 compared to low-z Type 1 AGN, explained via Cloudy modeling with near-unity covering factor and high column density.
The quasar J1512+4422 at z~6.2 lies on the local M_BH-σ_* relation and powers an outflow whose mass and energy loss rates exceed the host's star formation rate, indicating negative feedback.
LRDs transition from underdense low-halo-mass environments at z>4 to typical galaxy conditions by z~3.5, with halo growth leading to larger sizes and SED changes that explain their disappearance at lower redshifts.
DESI DR1 yields 314k high-mass and 9.6k dwarf AGN, extending the M_BH-M_star relation to log M_star ~7.8 and suggesting two evolutionary pathways for galaxies and black holes.
A theoretical model of a magnetized black hole envelope is developed to explain the broad emission lines and X-ray faintness observed in little red dots using co-rotating plasma clumps and limited X-ray sources.
JWST observations of ERQs show stratified gas kinematics via deblended optical emission lines, with UV lines dominated by scattered light and optical lines mixing scattered and obscured emission.
Low-luminosity AGN exhibit structure function slopes rising from 0.1 to 0.3 with black hole mass, no breaks on decadal scales, amplitude anticorrelated with luminosity and positively correlated with mass.
Paschen jumps in Little Red Dots indicate their continua originate from free-bound recombination emission in low-temperature nebular gas rather than thermalized or AGN components.
Five LRDs at z≈2 yield number density ≈7×10^{-6} cMpc^{-3}, confirming a decline from the z≈5 peak but gentler than prior photometric estimates.
Presents a public spectroscopic atlas of 887 Southern broad-line AGNs at low redshift, including continuum decompositions and emission-line fits.
Bayesian continuum fitting of 66 LRDs shows the BH* model fits ~6% best, rising to ~40% under AGN-disfavoring priors, with most objects stellar/AGN-dominated and possible evolutionary trends.
JWST IFU spectroscopy of six z~6 galaxies finds broad Balmer lines in two objects, a strong correlation of broad-line presence with Lyα luminosity yielding AGN fractions >77% above and <15% below 10^44 erg/s, plus extended star-forming gas in non-AGN hosts.
A z=4.556 QSO exhibits A_1500/A_V ≈8 with no 2175Å bump, taken as evidence for small-grain dominance from QSO-driven shattering or condensation.
LRDs require Compton-thick gas at moderate metallicity plus high accretion rates producing weak X-rays to explain their non-detection, implying they are not chemically pristine.
New JWST spectrum of a z=8.3 galaxy with prior ALMA dust detection shows AGN signatures, 0.15 Zsun metallicity, Mdust ~10^6 Msun, Tdust~91 K, and an [OIII] line ratio higher than nebular models allow.
Multi-epoch spectroscopy of UNAM-KIAS 613 shows transient double-peaked broad Hα emission interpreted as a one-time bipolar outflow in an isolated low-luminosity AGN with Eddington ratio ~0.03-0.04.
Multi-phase molecular gas in IRAS20551-4250 is dominated by cold CO, shows UV-heated warm H2, tidal features from a merger, and no molecular outflows, consistent with ongoing star formation.
Mass-scaled DRW damping timescales in AGNs follow a linear relation with black hole mass (slope 0.35-0.50) for both jetted and non-jetted sources, supporting universal accretion physics.
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The Missing Hard Photons of Little Red Dots: Their Incident Ionizing Spectra Resemble Massive Stars
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A Scaling Relation of LRDs between Broad H$\alpha$ and Bolometric Luminosities: Enhanced Broad H$\alpha$ Emission Relative to Low-$z$ Type 1 AGN
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Why Little Red Dots Disappear at z < 3: Evolution of Number Density and Halo Mass
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A Magnetized Black Hole Envelope Model for Little Red Dots
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Kinematic Stratification in Extremely Red Quasars Revealed by JWST
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Optical Variability Structure Function of Low-Luminosity AGN using ATLAS Lightcurves
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Paschen Jumps in Little Red Dots: Evidence for Nebular Continua
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Little Red Dots at z~2 in EIGER reveal a gentle decline with respect to their peak number density at z~5
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OzSSy1: The Australian Southern Seyfert-1 Spectroscopic Atlas and Catalogue at z < 0.1
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Aether-SHELLQs: JWST integral-field spectroscopy of candidate obscured quasars at z ~ 6
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A Steep-Extinction QSO at z=4.6: JWST Evidence for Abundant Small Dust Grains
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On the quenching of LRD X-ray emission by both Compton-thick gas and high accretion rates
LRDs require Compton-thick gas at moderate metallicity plus high accretion rates producing weak X-rays to explain their non-detection, implying they are not chemically pristine.
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DREAMS. JWST Spectroscopy of a $z=8.3$ Galaxy with an ALMA Dust Continuum Detection: Early Dust, Very High $T_{\rm dust}$, and a Multi-wavelength [OIII] Ratio Discrepancy
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Spectral Evolution and Transient Broad-Line Features in the Isolated AGN UNAM-KIAS 613
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GOALS-JWST: Resolved multi-phase molecular gas in IRAS 20551-4250 using JWST and ALMA
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A universal relationship between the variability timescale and black hole mass in black hole jetted and non-jetted accreting systems
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