Lonely Little Red Dots: Challenges to the AGN-nature of little red dots through their clustering and spectral energy distributions

Abstract

Observations with the James Webb Space Telescope (JWST) reveal a previously unseen population of compact red objects, known as ``little red dots`` (LRDs). We study a new photometrically selected sample of 124 LRDs in the redshift range $z$ $\sim$ 3 - 10 selected from NIRCam coverage of the CEERS, NEP-TDF, JADES and JEMS surveys. For JADES, the NEP-TDF and CEERS, we compare SED models with and without AGN components and analyse the impact of an AGN component on the goodness of fit using the Bayesian information criterion (BIC). We find that whilst the ${\chi }^2$ of the majority of models containing AGN components is improved compared to models without AGN components, we show that the BIC suggests models without AGN are a more appropriate fit to LRD SEDs, especially when MIRI data is available. We also measure LRD clustering in the CEERS field, JADES field, and NEP-TDF, where we compare the spatial distribution of LRDs and galaxies with Kolmogorov-Smirnov tests of equality of distribution. We find that the neighbourhood of LRDs tends to be less dense compared to galaxies at all selections and masses and at similar redshifts. We further measure upper limit estimates for the halo masses of LRDs using abundance matching. Whilst the population of LRDs could be a mixture of several different inherent populations, as a whole it does appear that these systems are mostly hosting compact galaxies or star clusters in formation.

arXiv comment24 pages, 17 figures, submitted to ApJL

References in corpus (61)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• Planck 2015 results. XIII. Cosmological parameters
• Stellar population synthesis at the resolution of 2003
• Galactic Stellar and Substellar Initial Mass Function
• The Dust Content and Opacity of Actively Star-Forming Galaxies
• The Astropy Project: Sustaining and Growing a Community-oriented Open-source Project and the Latest Major Release (v5.0) of the Core Package
• Coevolution (Or Not) of Supermassive Black Holes and Host Galaxies
• The Average Star Formation Histories of Galaxies in Dark Matter Halos from z=0-8
• CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey
• Infrared Emission from Interstellar Dust. IV. The Silicate-Graphite-PAH Model in the Post-Spitzer Era
• CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey - The Hubble Space Telescope Observations, Imaging Data Products and Mosaics
• Evolutionary population synthesis: models, analysis of the ingredients and application to high-z galaxies
• EAZY: A Fast, Public Photometric Redshift Code
• Toward a halo mass function for precision cosmology: the limits of universality
• The M-sigma and M-L Relations in Galactic Bulges and Determinations of their Intrinsic Scatter
• CIGALE: a python Code Investigating GALaxy Emission
• UniverseMachine: The Correlation between Galaxy Growth and Dark Matter Halo Assembly from z=0-10
• The SAURON project - IV. The mass-to-light ratio, the virial mass estimator and the fundamental plane of elliptical and lenticular galaxies
• The Large Scale Bias of Dark Matter Halos: Numerical Calibration and Model Tests
• Analysis of galaxy SEDs from far-UV to far-IR with CIGALE: Studying a SINGS test sample
• Formation of the First Supermassive Black Holes
• Inferring the star-formation histories of massive quiescent galaxies with BAGPIPES: Evidence for multiple quenching mechanisms
• The All-wavelength Extended Groth Strip International Survey (AEGIS) Data Sets
• Star Formation and Dust Attenuation Properties in Galaxies from a Statistical UV-to-FIR Analysis
• Andromeda's Dust
• The dust covering factor in active galactic nuclei
• Three-dimensional radiative transfer modeling of AGN dusty tori as a clumpy two-phase medium
• Rest-frame ultraviolet-to-optical spectral characteristics of extremely metal-poor and metal-free galaxies
• CEERS Epoch 1 NIRCam Imaging: Reduction Methods and Simulations Enabling Early JWST Science Results
• Evidence of Cosmic Evolution of the Stellar Initial Mass Function
• The JWST Early Release Observations
• The black hole mass -- stellar velocity dispersion correlation: bulges versus pseudobulges
• Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs). V. Quasar Luminosity Function and Contribution to Cosmic Reionization at z = 6
• Gaia Early Data Release 3: Summary of the contents and survey properties
• Confirmation and refutation of very luminous galaxies in the early universe
• Spectroscopic Confirmation of CEERS NIRCam-selected Galaxies at $\mathbf{z}\simeq 8-10$
• Evolution of supermassive stars as a pathway to black hole formation
• The stellar-to-halo mass relation over the past 12 Gyr
• JADES NIRSpec Initial Data Release for the Hubble Ultra Deep Field: Redshifts and Line Fluxes of Distant Galaxies from the Deepest JWST Cycle 1 NIRSpec Multi-Object Spectroscopy
• JWST's PEARLS: Prime Extragalactic Areas for Reionization and Lensing Science: Project Overview and First Results
• The Hubble Legacy Field GOODS-S Photometric Catalog
• JWST UNCOVER: Extremely red and compact object at$z_{\mathrm{phot}}\simeq 7.6$ triply imaged by Abell 2744
• A massive galaxy that formed its stars at $z\sim 11$
• Clumpy Galaxies in CANDELS. II. Physical Properties of UV-bright Clumps at $0.5\le z<3$
• RUBIES: a complete census of the bright and red distant Universe with JWST/NIRSpec
• The cosmic evolution of dust-corrected metallicity in the neutral gas
• Spectral Templates Optimal for Selecting Galaxies at z > 8 with JWST
• The Faint End of the Quasar Luminosity Function at $z\sim 5$ from the Subaru Hyper Suprime-Cam Survey
• Modelling type 1 quasar colours in the era of Rubin and Euclid
• Little Red Dots: Rapidly Growing Black Holes Reddened by Extended Dusty Flows
• JWST's PEARLS: a new lens model for ACT-CL J0102$-$4915, "EL Gordo'', and the first red supergiant star at cosmological distances discovered by JWST
• The dependence of the galaxy stellar-to-halo mass relation on galaxy morphology
• The evolution of clustering length, large-scale bias and host halo mass at 2<z<5 in the VIMOS Ultra Deep Survey (VUDS)
• The Formation of Supermassive Black Holes from Population III.1 Seeds. I. Cosmic Formation Histories and Clustering Properties
• Little Red Dots or Brown Dwarfs? NIRSpec Discovery of Three Distant Brown Dwarfs Masquerading as NIRCam-Selected Highly-Reddened AGNs
• Exploring the AGN Fraction of a Sample of JWST's Little Red Dots at $5<z<8$: Overmassive Black Holes Are Strongly Favored
• Sizes and Stellar Masses of the Little Red Dots Imply Immense Stellar Densities
• The NIRSpec Wide GTO Survey
• "Little red dots" cannot reside in the same dark matter halos as comparably luminous unobscured quasars
• NoSOCS in SDSS. V. Red Disc and Blue Bulge Galaxies Across Different Environments
• Paper 1: The JWST PEARLS View of the El Gordo Galaxy Cluster and of the Structure It Magnifies

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