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.
hub
VENUS: When Red meets Blue -- A multiply imaged Little Red Dot with an apparent blue companion behind the galaxy cluster Abell 383
10 Pith papers cite this work. Polarity classification is still indexing.
10
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.
hub tools
citation-role summary
background 1
citation-polarity summary
years
2026 10verdicts
UNVERDICTED 10roles
background 1polarities
background 1representative citing papers
Derives idealized P-L-T relation from hydrostatic envelope model for LRDs and uses sparse data to obtain preliminary H0 = 120.7 with large errors as proof-of-concept.
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
-
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.