Are we surprised to find SMBHs with JWST at z > 9?

2023/05/21 by Raffaella Schneider, Schneider, Raffaella, Rosa Valiante +8 · 5 citations
Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics of Galaxies (astro-ph.GA) #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #Pulsars and Gravitational Waves Research

paper · pdf · doi:10.48550/arxiv.2305.12504

openalex publication_date 2023/05/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

JWST is unveiling for the first time accreting black holes (BHs) with masses of 10⁶ - 10⁷ Msun at z > 4, with the most distant residing in GNz11 at z = 10.6. Are we really surprised to find them in the nuclei of z = 5 - 11 galaxies? Here we predict the properties of 4 < z < 11 BHs and their host galaxies considering an Eddington-limited (EL) and a super-Eddington (SE) BH accretion scenario, using the Cosmic Archaeology Tool (CAT) semi-analytical model. We calculate the transmitted spectral energy distribution of CAT synthetic candidates, representative of the BH/galaxy properties of GNz11. We also examine the possibility that the z = 8.7 galaxy CEERS-1019 could host an active BH. We find that the luminosity of high-z JWST detected BHs are better reproduced by the SE model, where BHs descend from efficiently growing light and heavy seeds. Conversely, the host galaxy stellar masses are better matched in the EL model, in which all the systems detectable with JWST surveys JADES and CEERS descend from heavy BH seeds. We support the interpretation that the central point source of GNz11 could be powered by a SE (lambda_Edd = 2 - 3) accreting BH with mass 1.5 10⁶ Msun, while the emission from CEERS-1019 is dominated by the host galaxy; if it harbours an active BH, we find it to have a mass of M_BH = 10⁷ Msun, and to be accreting at sub-Eddington rates (lambda_Edd = 0.5).

Cited by

• ALMA and JWST Imaging of z > 6 Quasars: No Spatial Position Offset Observed Between Quasars and Their Host Galaxies
• JWST provides a new view of cosmic dawn: latest developments in studies of early galaxies
• Heavy seeds and the first black holes: Insights from the BRAHMA simulations
• The ALPINE-CRISTAL-JWST Survey: Revealing Less Massive Black Holes in High-Redshift Galaxies
• The implications of overmassive black holes at z > 5 for quasar and black hole growth

Related

• The possible accretion discs of GN-z11 at redshift z = 10.6, MoM-z14 at z = 14.44 and other high redshift objects
• Beyond the Monsters: A More Complete Census of Black Hole Activity at Cosmic Dawn
• Episodic super-Eddington accretion as a clue to Overmassive Black Holes in the early Universe
• SHELLQs-JWST perspective on the intrinsic mass relation between supermassive black holes and their host galaxies at z > 6
• The Emerging Black Hole Mass Function in the High-Redshift Universe