English

The Little Red Dots Are Direct Collapse Black Holes

Astrophysics of Galaxies 2026-01-22 v1 Cosmology and Nongalactic Astrophysics High Energy Astrophysical Phenomena

Abstract

The discovery by JWST of a substantial population of compact "Little Red Dots" (LRDs) presents a major puzzle: their observed spectra defy standard astrophysical interpretations. Here, we show that LRD spectra are naturally reproduced by emission from an accreting Direct Collapse Black Hole (DCBH). Using radiation-hydrodynamic simulations, we follow the growth of the DCBH seed via a dense, compressionally heated, collisionally ionized accretion flow. The model self-consistently reproduces the screen responsible for the observed Balmer absorption, while allowing UV/optical emission to partially escape, along with reprocessed infrared radiation. Crucially, this structure is not a blackbody and requires no stellar contribution: the UV continuum originates entirely from reprocessed DCBH radiation, attenuated only by a small amount of dust with an extinction curve consistent with high-redshift galaxies. This single framework simultaneously explains the key observational puzzles of LRDs: (a) weak X-ray emission, (b) metal and high-ionization lines alongside absent star-formation features, (c) overmassive black holes, (d) compact morphology, (e) abundance and redshift evolution -- linking them directly to pristine atomic-cooling halos, (f) long-lived (>100>100 Myr), slowly variable phases driven by radiation pressure. Our findings indicate that JWST is witnessing the widespread formation of heavy black hole seeds in the early Universe.

Keywords

Cite

@article{arxiv.2601.14368,
  title  = {The Little Red Dots Are Direct Collapse Black Holes},
  author = {Fabio Pacucci and Andrea Ferrara and Dale D. Kocevski},
  journal= {arXiv preprint arXiv:2601.14368},
  year   = {2026}
}

Comments

Submitted. 17 pages, 4 figures