Weekly archive
LRDigestWeekly digests of little red dots and JWST-selected AGN papers, with curated reading notes and archive pages.
654 indexed papers · 430 research notes
JWST/NIRSpec CO v=1–0 emission across NGC 3256 S’s outflow base implies that the obscured AGN’s 4.7-μm radiation is anisotropic and likely collimated, though the inferred geometry depends on radiative-transfer assumptions.
In 12 z=4.17–5.54 compact broad-line emitters, Lyα is detected in six and is systematically narrower than broad Hα. Host-SED predictions correlate more closely with observed Lyα than nuclear Hα/UV, although excess Lyα permits nuclear emission.
Across 2,709 SMILES–JADES sources at 0.05<z<6, AGN luminosity tracks recent star formation and dust emission more strongly than stellar mass. PCA identifies activity and age axes, but the inferred cold-gas driver is an interpretation rather than a direct gas measurement.
Using JWST Paα spectroscopy, the authors find that radio-bright AGNs at z=1.1–1.5 occupy denser ∼1.5 pMpc environments than matched controls; density also correlates with accretion indicators, while environmental Paα luminosity functions are elevated and flatter at the faint end.
This framework treats JWST massive galaxies, AGN, and UV luminosity functions as host-halo supply tests. It finds that rare-halo abundance predictions depend strongly on high-redshift HMF calibration and assumed baryonic or black-hole mappings, precluding simple source-by-source consistency claims.
Using JWST mid-infrared IFS of NGC 5728, the authors decompose blended circumnuclear line emission into a star-forming ring and AGN bicone. Stacking twelve tracers yields spatial flux fractions that are stable across tested weighting choices.
![Figure 4 from Search for High-Ionization Nebular Emission (SHINE). I. A Systematically Selected [Ne V] Sample at z > 3 with JWST/NIRSpec PRISM](/lrdigest/research/figures/2609.27130v1/figure-4-1.png?v=1f796e8992092206)
SHINE identifies 25 luminous [Ne V] emitters at z=3.06–9.44 from >9,000 JWST/NIRSpec PRISM galaxies. Their hard-ionization lines favor accretion, but heterogeneous selection and incomplete diagnostic overlap preclude an intrinsic AGN-incidence measurement.
JWST MIRI/Spitzer hydrogen-line measurements in 27 dusty z~1–2 infrared galaxies yield directly inferred nebular attenuation declining from ~3 mag near 2 μm to ~1 mag near 4 μm, yet IR-based SFRs remain ~2.5 times higher.
JWST spectra of the single dusty galaxy AzTEC-1 at z=4.3419 reveal a broad Hα component blueshifted by 1245 km s⁻¹. The authors favor a candidate sub-pc SMBH binary or recoiling SMBH over an ionized outflow, but confirmation requires resolved follow-up.
Skyfire’s CEERS NIRSpec census finds broad Balmer emission across redder LRDs and somewhat bluer candidates, motivating an expanded continuum-slope selection. The color trend is suggestive of continuity with blue broad-line sources, but uneven targeting prevents a definitive population-unification claim.
A reionization-budget calculation argues that, if faint z=3–7 Little Blue Dots are common and leak ionizing radiation efficiently, most cannot be highly super-Eddington: their hard EUV spectra would complete He II reionization earlier than allowed.
A DJA census identifies 20 compact, blue broad-line emitters at z=4–7. Model-dependent escape fractions imply they provide a modest global ionizing budget at z≈5, while potentially dominating radiation locally over few-Mpc scales.
Spatially resolved JWST/MIRI spectroscopy of five nearby AGN links contrasting PAH-ratio trends to AGN irradiation and shock-processing diagnostics. The authors interpret their coexistence as a route to nuclear PAH suppression and to divergent PAH star-formation calibrations.
![Figure 5 from Implications of Broad [O III] 4364 and UV Line Emission in Two Little Red Dots at z ~ 7 - 8](/lrdigest/research/figures/2608.04101v1/figure-5-1.png?v=d97d8fa8c5c52d9f)
Deep JWST/NIRSpec spectra of two z=6.68–8.35 LRDs associate broad [O III] λ4364 with dense gas and mixed stellar/accretion ionization; however, inferred parsec-scale structure relies on temperature and virial assumptions.
AESOPICA forward-models JWST broad-line selection in 12 cosmological simulations, finding that selection can yield apparently overmassive AGN from several seed scenarios; very light seeds nevertheless require unusually efficient, intermittently super-Eddington growth in the explored models.
Using GOODS-S JWST SMILES+JADES photometry and CIGALE fits, the authors report that obscured-AGN incidence and infrared contribution rise toward high redshift, but are consistent with no systematic dependence on total infrared luminosity within their uncertainties.
JWST IFU spectroscopy and NIRCam imaging resolve GN-77652 at z=5.229 beside a ≈12-kpc, four-source filament. Its modest internal velocity gradient is modelled as rotation, while the filament’s coherent kinematics and a possible nearby second AGN indicate an assembling, complex environment.
JWST/MIRI resolves dusty point sources across Centaurus A’s warped disc: 928 red infrared-excess objects are consistent with embedded young stellar objects and follow the disc rather than the radio jet, favoring merger-accreted gas as the immediate star-formation reservoir.
MEOW uses JWST/MIRI hot-dust selection over GOODS to identify 16 z≳5 AGN candidates, mostly not previously selected as broad-line AGN. Its luminosity-function comparison suggests an obscured population comparable in abundance to broad-line AGN near log Lbol≈45, but faint-end constraints remain limited.
This paper uses spatially resolved CIGALE SED fitting to separate the ∼1 kpc nuclear core of GN20 from the full 9.9 kpc galaxy, combining JWST NIRCam, MIRI, NIRSpec PRISM pseudo-continuum, HST, and millimeter data. The central result is that the galaxy-wide SED is overwhelmingly star-formation powered, with only a marginal integrated AGN fraction of 0.09 ± 0.02, while the nucleus requires a much stronger AGN contribution of 0.34 ± 0.05 to explain a rest-frame 2.5–3.6 μm mid-infrared excess from torus-heated dust. That means the AGN contributes about one-third of the nuclear infrared luminosity but only about 9% of the total L_IR, naturally explaining why integrated diagnostics and earlier Spitzer limits made the source look starburst-dominated. The broader significance is that GN20 looks like a buried-black-hole case where only JWST-resolution, nuclear-scale decomposition can uncover ongoing early SMBH growth inside an extreme z = 4.055 dusty starburst.
This forecasting study argues that multi-frequency SKAO continuum observations could separate intrinsically weak, Compton-thick, and ionized-cocoon interpretations of radio-faint JWST AGN and LRDs, but it presents sensitivity-based predictions rather than new radio detections.
JWST/NIRSpec slit spectroscopy finds offset peaks in [O III]/Hβ relative to continuum light in 12 CEERS galaxies at 3<z<8. These are candidate off-nuclear ionizing regions, not direct detections of wandering black holes.
JWST/MIRI PCA tomography recovers 11.3-μm PAH velocity maps in three of five z~0.1 type-2 quasars; all three show dust-traced outflow kinematics, with molecular-gas residuals consistent with outflow after disk subtraction.
In 65 PRIMER-UDS post-starbursts at z=1–2, massive systems mostly lack mid-IR excess: template tests place population-level obscured accretion below 1% Eddington. Low-mass PSBs instead show 18-μm excess plausibly associated with residual star formation.
In the J0226+0302 quasar sightline, 73 line-emitting galaxies trace a tentative, 10–40 cMpc enhancement in IGM transmission, while four broad-line AGN show a possible smaller-scale enhancement. The results favor local ionizing-background variations but remain statistically and model limited.
Across six JWST/NIRSpec IFU targets at z=3–9, resolved stellar-population histories associate strong AGN-driven ionized outflows with recent nuclear quenching in the most massive systems, while starburst-driven outflows accompany continued growth in lower-mass galaxies.
JWST/NIRSpec IFU spectroscopy of six z~6 SHELLQs narrow-Lyα candidates finds secure broad Balmer components in two, while extended, largely non-rotating ionized gas characterizes several non-broad-line systems. Broad-line incidence rises sharply with Lyα luminosity.
Across 21,428 COSMOS-Web galaxies, two SED codes and deep-learning imaging agree well when AGN light is negligible but diverge sharply for AGN-significant systems. Imaging-constrained refits can materially shift host properties despite acceptable photometric fits.
Spatially resolved JWST, ALMA and KCWI data support a multiphase, minor-axis biconical outflow in the dusty local merger IRAS F01364-1042. The authors infer faster ionized than molecular gas and argue a nuclear starburst can energetically drive it despite an obscured AGN.
Across a large SDSS–eROSITA quasar sample, bolometric luminosity scales nearly linearly with virial black-hole mass while hard X-rays rise more slowly. The authors argue this disfavors classical Bondi feeding and favors CCA, but redshift covariances and JWST line-based systematics limit interpretation.
This paper searches JWST/NIRSpec archival spectra of 87 massive quenched galaxies at z≈1.5-4.5 and finds [NeV] λ3427 in six, arguing that this coronal line cleanly isolates luminous SMBH accretion in systems where residual star formation is not a viable explanation. Four of the six [NeV] hosts also show broad Hα with FWHM ≳ 4000 km s^-1, implying MBH ≈ 10^8.5-10^9.5 Msun, while the [NeV] luminosities indicate quasar-like power outputs of roughly 10^45-10^46 erg s^-1 and Eddington ratios of about 10-50%. The strongest [NeV] emitters sit in the youngest post-starburst galaxies with Dn4000 ≲ 1.3, whereas older quenched systems lack comparable activity, pointing to intense radiatively efficient black-hole growth that can continue for several hundred Myr after the main quenching event. That timing matters because it links early quenching to delayed but still powerful SMBH growth, and provides a concrete empirical target for models that aim to produce the first massive passive galaxies.
Using AGN-aware fits to JWST spectra, the authors report that non-LRD broad-line AGN shift from elevated observed M_BH/M* above z≈4.5 to the local relation by z≈3.5; LRD host-mass inferences remain substantially less secure.
For the single z=8.312 galaxy MACS0416-Y1, deep JWST/NIRSpec plus archival IFU/ALMA data support a broad-line AGN interpretation, low metallicity and dust mass ratios, and a spatially non-coincident origin for optical and far-infrared [OIII].
JWST/MIRI-MRS resolves a warm-H₂ outflow in the composite ULIRG F10565+2448: it is hotter than the disk but apparently sub-escape-speed, while a faster unresolved ionized component and localized shock candidates support multiphase feedback.
JWST/MIRI-MRS mapping of seven nearby radio-loud AGN links elevated warm-H2 excitation and broadened multiphase gas to radio-jet environments, including transverse regions. The authors interpret the correlations as predominantly jet-driven shocks, while recognizing source-dependent exceptions.
After image decomposition and host-only SED fitting, 36 NIRCam-selected NEP-TDF AGN candidates separate into a likely AGN “branch” and an ambiguous, largely early-type “bridge” near quenching; the reported SFR–AGN-fraction trend is weakly explanatory.
JWST/NIRSpec spectra of two z~6.6 ultra-luminous Lyα emitters reveal broad Balmer-line black-hole masses near 2×10^8 M⊙ and double-peaked Lyα, which the authors interpret as brief post-quasar phases inside relic ionised bubbles.
JWST IFU spectroscopy of NGC 7582 separates rotating circumnuclear-disk gas from an AGN bicone by ionisation potential and line-profile decomposition, finding distinct kinematic axes and broader outflow lines; mixed-ionisation tracers require two components.
Medium-resolution JWST/NIRSpec data spatially separate an LRD-like AGN and its host at z=6.64, revealing exceptionally broad ionised gas consistent with AGN driving but a low inferred mass-loading factor and therefore limited immediate star-formation impact.
Deep NOEMA observations of three z>6 JWST AGN—two Little Red Dots and one blue Type-I source—yield no significant [C II] or dust-continuum detection, tightening host-galaxy and SED constraints while leaving the physical origin of their [C II] deficit unresolved.
Using JWST/MIRI-selected sources, MEOW infers that obscured AGN become increasingly dominant with redshift: its SED-based luminosity functions imply a 98–99% obscured fraction at z=4.5–6 for luminous AGN, relative to UV type-1 quasars.
This lecture-based review argues that JWST has converted early luminous-quasar studies from rest-UV, ground-based inference to rest-optical spectroscopy and resolved host/environment measurements, while supporting—within virial-estimator uncertainty—the pre-JWST Mg II black-hole mass scale.
Two z≈0.7 compact dwarfs combine blue, burst-dominated UV–optical emission with a MIRI hot-dust excess. SED-inferred AGN luminosities imply candidate black holes disproportionately massive for ≈10^7 M⊙ hosts, but masses depend strongly on the assumed Eddington ratio.
JWST IFU observations of 10 local Seyferts use PCA tomography of broad PAH bands to map dust-phase kinematics. The authors report neutral, larger PAHs sharing molecular and ionised-outflow signatures in NGC 5728 and NGC 7582, while 3.3 μm PAHs trace disks.
High-redshift LRDs and JWST-selected broad-line AGN are X-ray weak relative to broad Hα, plausibly resembling highly accreting local systems; however, predominantly upper-limit-based X-ray constraints leave intrinsic coronal suppression and obscuration unresolved.
Forward-modeling broad-Hα selection in a JADES broad-line AGN sample at z≳4 yields an M_BH–M★ relation consistent in mean with local relations but with 0.63 dex intrinsic scatter, implying diverse early black-hole growth histories.
Joint modelling of broad lines and Chandra non-detections for 14 JWST high-redshift broad-line AGNs favors low-mass, highly super-Eddington black holes with over-cooled coronæ over massive, weakly accreting alternatives, but the inference remains model-dependent and bimodal.
A data-driven demographic consistency test finds that the abundant faint JWST AGN at z≈5.5 can be explained by moderately elevated black-hole–stellar-mass scaling relations and ∼50% duty cycles, without requiring the most extreme inferred black-hole masses.
JWST NIRSpec/MIRI nuclear spectra of eight LLAGN plus Cen A associate decreasing [Ne V]-to-X-ray output below log(Lbol/LEdd)≈−3.5 with a UV-deficient ionizing SED, while finding warmer rotational H2 and predominantly nuclear silicate emission.
JWST/NIRCam decomposition detects extended host emission in 9 of 17 broad-Hα AGN at z≈4–6. Separating point-source light can reduce inferred host masses by 1–2 dex, yielding high BH-to-stellar mass ratios, although unresolved compact hosts remain a viable alternative.
This resource catalogue consolidates 3,242 AGNs in JWST observations through 20 March 2025, combining proposal-based target identification with footprint cross-matches. It is an access and sample-discovery product, not a uniform AGN survey or a measurement of AGN demographics.
JWST spectroscopy identifies a lensed z=5.96 “pseudo-LRD” whose red optical colour is Hα-line driven, yet whose broad Hα supports a ∼3×10^6 M⊙ black hole embedded in a dusty, dense, very metal-poor starburst.
JWST/HST observations of the lensed z≈6.87 galaxy A2744-z7DLA reveal damped Lyα absorption plus a statistically preferred broad Hα component, supporting a gas-enshrouded broad-line AGN interpretation while its UV–optical continuum remains predominantly stellar.
JWST 3–28 μm nuclear spectroscopy of four low-luminosity AGN associates weak high-ionization emission, shock-like line ratios, altered PAH populations, and non-thermal H₂ excitation with feedback, while leaving the proposed jet connection indirect.
JWST/MIRI imaging of eight nearby Seyferts finds resolved 100–200 pc NLR dust in four. Its warm, steep mid-IR SEDs exceed simple AGN-heating predictions; the authors therefore favor local shock heating, while treating shocks as an interpretation rather than a direct calorimetric detection.
New JWST/NIRSpec IFU spectroscopy classifies LAE2, ~30 kpc from the quenched z=3.064 galaxy GS10578, as an AGN, completing a three-AGN environment; LAE1 is instead plausibly Lyα light scattered from LAE2.
Using JWST/NIRSpec prism spectra, the authors find that strong C III] emission is common among 61 galaxies at z=5–7 and often coincides with AGN indicators, but upper limits and prism resolution leave many classifications provisional.
JWST/MIRI plus MUSE resolves a dusty, multiphase ionized outflow in NGC 1068: [O IV] is 300 km s⁻¹ faster than [O III], and the authors infer that optical data miss much of the ionized outflow mass.
JWST/NIRSpec IFU maps of four dwarf AGN with [O III] outflows find extended, predominantly AGN-photoionized near-IR coronal emission and compact broad components. The results link coronal-line visibility to outflows, but small-sample correlations do not establish causation.
Two z~3 X-ray AGNs with He I λ10830 absorption indicate dense, broad-line-region-scale circumnuclear gas, but their contrasting obscuration, accretion rates, and outflow signatures provide only a two-object, model-dependent case for an evolutionary sequence.