Identifying Direct Collapse Black Hole Seed Candidates in the Cosmic Dawn
DOI:
https://doi.org/10.2218/esjs.12365Keywords:
Cosmic Dawn, Simulation, Black Hole, Dark Matter HaloAbstract
The discovery of billion-solar-mass quasars at z≈6 has raised a timing problem for supermassive black hole growth, motivating the Direct Collapse Black Hole (DCBH) scenario as a possible solution. We performed high-resolution Enzo zoom-in simulations targeting the six most massive halos in a 1 (Mpc/h)3 comoving volume by z=10. All six halos exceed the atomic cooling threshold (Tvir ≳ 104 K). Of these, the second and third largest halos by mass within the simulation volume (Halo 2 and Halo 3) additionally satisfy criteria for Lyman-Werner proximity and rapid growth dynamics, exhibiting runaway accretion rates (M ≳ 106 M⊙/Myr) and physical separations below the summed virial radii of neighbouring massive halos. Across the sample, smooth accretion accounts for approximately 80% of total mass growth, underscoring its role over mergers in driving rapid assembly. These results identify Halo 2 and Halo 3 as DCBH seed candidates that satisfy our criteria and offer preliminary context relevant to early SMBH seed formation scenarios, such as those proposed for JWST’s ‘Little Red Dots’.
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