The emergence and ionizing feedback of Pop III.1 stars as progenitors for supermassive black holes
Year: 2025
Type: article
Abstract: ABSTRACT Recent observations by James Webb Space Telescope reveal an unexpectedly abundant population of rapidly growing supermassive black holes (SMBHs) in the early Universe, underscoring the need for improved models for their origin and growth. Employing new full radiative transfer hydrodynamical simulations of galaxy formation, we investigate the local and intergalactic feedback of SMBH progenitors for the Population III.1 (Pop III.1) scenario, i.e. efficient formation of supermassive stars from pristine, undisturbed dark matter minihaloes. Our cosmological simulations capture the R-type expansion phase of these Pop III.1 stars, with their H-ionizing photon luminosities of ${\sim} 10^{53} \, {\rm s}^{-1}$ generating H ii regions that extend deep into the intergalactic medium, reaching comoving radii of $r_{\rm H\,\small {II}} \sim 1\, \text{cMpc}$. We vary both the Pop III.1 ionization flux and cosmological formation environments, finding the former regulates their final $r_{\rm H\, \small {II}}$, whereas the latter is more important in setting their formation redshift. We use the results from our radiation-hydrodynamics simulations to estimate the cosmic number density of SMBHs, $n_{\mathrm{SMBH}}$, expected from Pop III.1 progenitors. We find $n_{\mathrm{SMBH}} \sim 10^{-1}\, \mathrm{cMpc}^{-3}$, consistent with the results inferred from recent observations of the local and high-redshift universe. Overall, this establishes Pop III.1 progenitors as viable candidates for the formation of the first SMBH, and emphasizes the importance of exploring heavy mass seed scenarios.
Institutions: University of Oxford, Chalmers University of Technology, University of Virginia, Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, University of Trieste, University of Memphis, Trieste Astronomical Observatory, Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, Institute for Fundamental Physics of the Universe, National Institute for Astrophysics, University of Modena and Reggio Emilia, Brera Astronomical Observatory, Stockholm University, AlbaNova
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,046
Funders: National Science Foundation, National Aeronautics and Space Administration, Dell EMC, Department for Business, Energy and Industrial Strategy, UK Government, Colorectal Cancer Alliance, Space Telescope Science Institute, Universities Space Research Association, European Commission, Durham University, Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, Universität Stuttgart, Engineering and Physical Sciences Research Council, Science and Technology Facilities Council, H2020 European Research Council
Awards: G1134310069, G1468651527, DiRAC-2.5 - the pathway to DiRAC Phase 3, G2309215924, G2368581224, Peta-5: A National Facility for Petascale Data Intensive Computation and Analytics, G2656428114, G2843074508, G358276009, G4251892262, Phasenübergänge und Instabilitäten, G433322167, G4387011080, G5274026675, G58316358, G6273510985, DiRAC-2.5 DC - Operations 2017-2020, DiRAC: Memory Intensive 2.5y, Connecting galaxy formation and Cosmic Reionization, Massive Star Formation through the Universe, DiRAC: Memory Intensive 2.5x, G972786147, G977319879
OpenAlex ID: W4413184058