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.
VENUS: When Red meets Blue -- A multiply imaged Little Red Dot with an apparent blue companion behind the galaxy cluster Abell 383
9 Pith papers cite this work. Polarity classification is still indexing.
9
Pith papers citing it
abstract
We report the discovery of a doubly-imaged Little Red Dot (LRD) candidate behind the galaxy cluster Abell 383, which we dub A383-LRD1. Initially classified as a dropout galaxy in HST imaging with several ground-based emission line detections placing it at $z_{\mathrm{spec}}=6.027$, new JWST/NIRCam observations taken as part of the cycle 4 VENUS survey now reveal that the source consists of two underlying components: A red point-source with a V-shaped SED consistent with LRD selection criteria, and a nearby ($\sim 380$ pc) compact blue companion which was the main contributor to the previous rest-frame UV detections. Based on lensing symmetry and its SED, the LRD appears to lie at a similar redshift as well. The magnification of the two images of A383-LRD1 is $\mu_{\mathrm{A}}=16.2\pm1.2$ and $\mu_\mathrm{B}=9.0\pm0.6$, respectively, and the predicted time delay between them is $\Delta t_{\mathrm{grav}}=5.20\pm0.14$ yr ($\sim0.7$ yr in the rest-frame). After correcting for the lensing magnification, we derive an absolute magnitude of $M_{\mathrm{UV,LRD}}=-16.8\pm 0.3$ for the LRD, and $M_{\mathrm{UV,BC}}=-18.2\pm 0.2$ for the blue companion. We perform SED fits to both components, revealing the LRD to be best fitted with a black hole star (BH*) model and a substantial host galaxy, and the blue companion with an extremely young, emission-line dominated star-forming nebula. A383-LRD1 represents the second known multiply-imaged LRD detected to date, following A2744-QSO1, and to our knowledge, the first LRD system with a confirmed detection of [C $_{II}$]$\lambda158 \ \mu$m emission from ALMA observations. Thanks to lensing magnification, this system opens a unique door to study the relation between a LRD, its host galaxy, and its environment, and represents a prime candidate for deep JWST spectroscopy and high-resolution ALMA follow-up observations.
citation-role summary
background 1
citation-polarity summary
years
2026 9verdicts
UNVERDICTED 9roles
background 1polarities
background 1representative citing papers
Close compact pairs mark ~67% of known Little Red Dots and both high-redshift BLAGNs in the A2744 field, suggesting merger-driven accretion at high redshift.
Analysis of ~100 JWST LRDs finds redder, compact UV emission with Fe II/Mg II ~8-10 and correlations suggesting central red continuum (β_UV~0) beyond host galaxy contribution.
UV-bright companions to Little Red Dots provide Lyman-Werner fluxes of J21 ~ 10^2.5-10^5 that can suppress H2 cooling and enable direct collapse to massive black holes.
JWST data on LRDs and LBDs show AGN-like excitation, strong Lyα with broad components, and X-ray weakness, implying clumpy or equatorial geometries around growing black holes rather than complete gas envelopes.
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.
Red supergiant collisions with massive gaseous envelopes around SMBHs in LRDs can produce detectable transients at rates up to ~0.3 yr^{-1} per LRD for compact clusters of size ≲10 pc.
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.
A review summarizing recent advances in strong gravitational lensing applications and near-future prospects with the James Webb Space Telescope.
citing papers explorer
-
The metallicities of little red dot host galaxies: LRDs are metal poor, but not pristine
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.
-
Double Dots: Compact Pairs Mark Little Red Dots and High-Redshift Broad-line AGNs
Close compact pairs mark ~67% of known Little Red Dots and both high-redshift BLAGNs in the A2744 field, suggesting merger-driven accretion at high redshift.
-
The UV Side of Little Red Dots: Red, Compact, and Iron-Enhanced Rest-UV Emission with a Strong Downturn around Ly$\alpha$
Analysis of ~100 JWST LRDs finds redder, compact UV emission with Fe II/Mg II ~8-10 and correlations suggesting central red continuum (β_UV~0) beyond host galaxy contribution.
-
Connecting the Dots: UV-Bright Companions of Little Red Dots as Lyman-Werner Sources Enabling Direct Collapse Black Hole Formation
UV-bright companions to Little Red Dots provide Lyman-Werner fluxes of J21 ~ 10^2.5-10^5 that can suppress H2 cooling and enable direct collapse to massive black holes.
-
Little Red and Blue Dots: AGN-excited narrow lines, Lyman-$\alpha$ emission, and resemblance to standard quasars
JWST data on LRDs and LBDs show AGN-like excitation, strong Lyα with broad components, and X-ray weakness, implying clumpy or equatorial geometries around growing black holes rather than complete gas envelopes.
-
Between Degeneracy and Evolution: UV-to-optical Insights into the BH$^*$ Model in Little Red Dots
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.
-
Transient Signatures of Star-Envelope Collisions in Little Red Dots
Red supergiant collisions with massive gaseous envelopes around SMBHs in LRDs can produce detectable transients at rates up to ~0.3 yr^{-1} per LRD for compact clusters of size ≲10 pc.
-
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.
-
Strong Gravitational Lensing with the James Webb Space Telescope
A review summarizing recent advances in strong gravitational lensing applications and near-future prospects with the James Webb Space Telescope.