Papers › Dust in Little Red Dots

Dust in Little Red Dots

6 Jul 2024arXiv:2407.05094links table onlyarchive 2025-07-28

Caitlin M. Casey, Hollis B. Akins, Vasily Kokorev, Jed McKinney, Olivia R. Cooper, Arianna S. Long, Maximilien Franco, Sinclaire M. Manning

The archive published only this paper's code-link row. Authors, date and abstract are from arXiv's metadata (CC0), read from the Kaggle arXiv metadata snapshot of 2026-09-12 where its title matched the archive's; the title is the archive's.

JWST has revealed a ubiquitous population of ``little red dots'' (LRDs) at z≳4, selected via their red rest-frame optical emission and compact morphologies. They are thought to be reddened by dust, whether in tori of active galactic nuclei or the interstellar medium (ISM), though none have direct dust detections to date. Informed by the average characteristics of 675 LRDs drawn from the literature, we provide ballpark constraints on the dust characteristics of the LRD population and estimate they have average dust masses of ⟨M_(dust)⟩=(1.6^(+4.8)_(-0.9))×10⁴ M_⊙, luminosities of ⟨L_(IR)⟩=(8⁺³₋₅)×10¹⁰ L_⊙ and temperatures of ⟨T_(dust)⟩=110⁺²¹₋₃₆ K. Notably, the spectral energy distributions are thought to peak at ∼100 K (rest-frame 20-30 μm) regardless of heating mechanism, whether AGN or star formation. LRDs' compact sizes R_(eff)∼100 pc are the dominant factor contributing to their low estimated dust masses. Our predictions likely mean LRDs have, on average, submillimeter emission a factor of ∼100× fainter than current ALMA limits provide. The star-to-dust ratio is a factor ∼100× larger than expected from dust formation models if one assumes the rest-optical light is dominated by stars; this suggests stars do not dominate. Despite their high apparent volume density, LRDs contribute negligibly (0.1%) to the cosmic dust budget at z≳4 due to their low dust masses.

PaperPDFCode

Code

Repository list and official/mentioned flags are the archive's, frozen 2025-07-28. Reachability, where shown, is from one Syntology probe window (2026-09-16 to 2026-09-18); repositories not probed show nothing. GitHub stars are not tracked.

Code Syntology ran Syntology

Not run by Syntology. Nothing on this page verifies that the listed code works.

Results from the paper archive 2025-07-28

No leaderboard rows for this paper in the archive.

Report a problem or propose a change · a person checks every report against the paper or source before anything changes; decisions are listed on /corrections