LRDs are interpreted as high-inclination hyper-Eddington accreting SMBHs analogous to SS 433, with V-shaped SEDs, X-ray weakness, and Balmer breaks emerging from disk self-shielding geometry.
The GlimmIr: Spectroscopic Variability in a z~7 LRD Indicates Rapid Changes in Both the Narrow and Broad Line Regions
3 Pith papers cite this work. Polarity classification is still indexing.
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Pith papers citing it
abstract
The enigmatic population of ``Little Red Dots'' (LRDs) sit at the center of some of the largest debates in extragalactic astronomy today. The source(s) of ionizing emission and the physical scale over which it governs is still largely unknown. We show for the first time spectroscopic variability in a z ~ 7 LRD. Comparing a recently obtained 10.2 hr JWST/NIRSpec F290LP/G395M spectrum via the C3PO survey to an 8.4 hr F290LP/G395M spectrum taken 99 days earlier (~13 rest-days) via the THRILS survey, we find a ~30% $ difference in the continuum and broad-line flux, and a 42% difference between [OIII]5008 flux in the two epochs. Through rigorous testing, we confirm that such differences are not the result of differing MSA slit placements on source nor merely flux calibration offsets. These results are further corroborated by both a similar continuum and [OIII]5008 flux differences found in NIRSpec prism/clear observations of the source at an epoch taken approximately a year earlier than the THRILS observations via RUBIES and an additional observation fortuitously taken during the THRILS epoch (within a rest-day) via the CAPERS survey. Assuming LRDs are a type of accreting black hole system, this implies direct sight-lines must exist from the accretion disk to the surrounding nebular gas on scales beyond the broad-line region, and thus any high-density gas interpretations must allow for covering fractions < 100%. Furthermore, these results show the [OIII] line emission is likely not galaxy process-dominated, with a significant population of the narrow-line emitting gas closest to the broad-line region being directly ionized by the LRD. Finally, these results highlight the need for new approaches in inferring black hole properties of these systems, accounting for the lack of significant ionization via star formation, and/or exploring more exotic host-galaxy conditions at these early epochs.
years
2026 3verdicts
UNVERDICTED 3representative citing papers
Narrow-line diagnostics on ~20 LRDs indicate that stellar photoionization alone cannot explain the observed ratios in many objects, implying anisotropic ionizing radiation from complex gas geometry.
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.
citing papers explorer
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Little Red Dots as Supermassive Analogs of SS 433
LRDs are interpreted as high-inclination hyper-Eddington accreting SMBHs analogous to SS 433, with V-shaped SEDs, X-ray weakness, and Balmer breaks emerging from disk self-shielding geometry.
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Constraints on the Gas Geometry Surrounding Little Red Dots through Narrow-Line Diagnostics
Narrow-line diagnostics on ~20 LRDs indicate that stellar photoionization alone cannot explain the observed ratios in many objects, implying anisotropic ionizing radiation from complex gas geometry.
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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.