The Little Red Dots Are Direct Collapse Black Holes

Fuente: arXiv
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Main Authors: Pacucci, Fabio, Ferrara, Andrea, Kocevski, Dale D.
Format: Preprint
Published: 2026
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_version_ 1866909996454772736
author Pacucci, Fabio
Ferrara, Andrea
Kocevski, Dale D.
author_facet Pacucci, Fabio
Ferrara, Andrea
Kocevski, Dale D.
contents 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 ($>100$ 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.
format Preprint
id arxiv_https___arxiv_org_abs_2601_14368
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle The Little Red Dots Are Direct Collapse Black Holes
Pacucci, Fabio
Ferrara, Andrea
Kocevski, Dale D.
Astrophysics of Galaxies
Cosmology and Nongalactic Astrophysics
High Energy Astrophysical Phenomena
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 ($>100$ 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.
title The Little Red Dots Are Direct Collapse Black Holes
topic Astrophysics of Galaxies
Cosmology and Nongalactic Astrophysics
High Energy Astrophysical Phenomena
url https://arxiv.org/abs/2601.14368