GLIMPSED: Direct evidence for a fast AGN-driven outflow from a z=6.64 Little Red Dot host galaxy
Abstract
We report the discovery of GLIMPSED-329380, a z=6.64 galaxy behind Abell S1063, which shows signs of an extreme ionised outflow driven by an active galactic nucleus (AGN). The deep JWST/NIRSpec medium grating observations show spatially resolved structures of a host galaxy containing the very fast outflow and an AGN, which we analyse separately. The outflow, mainly traced by broad [O III]{\lambda}5008 and H{\alpha} emissions in the host, reaches a full-width half-maximum velocity of ~5500km/s, velocities only observed in AGN-dominated systems. From the Balmer decrement, we observe that while the narrow emission lines show no dust attenuation, the outflowing gas is dusty. We use emission lines diagnostics to infer gas abundances within the host galaxy. The oxygen abundance is 12+log(O/H) ~ 7.95 (~18% solar) and the host is slightly nitrogen-enriched with log(N/O) ~ -0.75. Despite its extreme velocity, the mass loading factor (<0.1) and the kinematic energy of the outflow (~10^43 erg/s) suggest limited impact on star formation. The AGN component shows many similarities with little red dots (LRDs): a characteristic "V-shape", exponential profile in hydrogen lines, numerous detection of forbidden [Fe II] lines, a Balmer break, and a broad absorption feature at ~4550 {\AA}. This detection of a fast outflow in an LRD, rare in surveys dominated by low-resolution (e.g. PRISM) spectra, provides direct evidence of AGN activity in these systems.
Cite
@article{arxiv.2604.08687,
title = {GLIMPSED: Direct evidence for a fast AGN-driven outflow from a z=6.64 Little Red Dot host galaxy},
author = {Damien Korber and Rui Marques-Chaves and Daniel Schaerer and Gabriel Brammer and Archana Aravindan and Arghyadeep Basu and Qinyue Fei and Emma Giovinazzo and Vasily Kokorev and Alberto Saldana-Lopez and Maxime Trebitsch and Hakim Atek and John Chisholm and Ryan Endsley and Seiji Fujimoto and Lukas Furtak and Richard Pan and Rohan P. Naidu},
journal= {arXiv preprint arXiv:2604.08687},
year = {2026}
}
Comments
14 pages, submitted to A&A