We use cosmological adaptive mesh refinement code enzo zoom-in simulations to study the long-term evolution of the collapsing gas within dark matter haloes at z. This direct collapse process is a leading candidate for rapid formation of supermassive black hole (SMBH) seeds. To circumvent the Courant condition at small radii, we apply the sink particle method, focusing on evolution on scales ∼0.01–10 pc. The collapse proceeds in two stages, with the secondary runaway happening within the central 10 pc. The sink particles form when the collapsing gas requires additional refinement of the grid size at the highest refinement level. Their growth is negligible with the sole exception of the central seed which grows dramatically to Mseed ∼ 2 × 106 M in ∼2 Myr, confirming the feasibility of this path to the SMBH. The variability of angular momentum in the accreted gas results in the formation of two misaligned discs. Both discs lie within the Roche limit of the central seed. While the inner disc is geometrically thin and weakly asymmetric, the outer disc flares due to turbulent motions as a result of the massive inflow along a pair of penetrating filaments. The filamentary inflow determines the dominant Fourier modes in this disc – these modes have a non-self-gravitational origin. We do not confirm that m = 1 is a dominant mode that drives the inflow in the presence of a central massive object. The overall configuration appears to be generic, and is expected to form when the central seed becomes sufficiently massive.

Document Type


Publication Date


Notes/Citation Information

Published in Monthly Notices of the Royal Astronomical Society, v. 456, issue 1, p. 500-511.

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2015 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.

The copyright holders have granted the permission for posting the article here.

Digital Object Identifier (DOI)


Funding Information

IS acknowledges support from NSF grant AST-0807760 and from HST/STScI grant AR-12639.01-A. IS and KN are grateful for support from International Joint Research Promotion Program at Osaka University. JHC acknowledges support from NASA ATP NNX11AE09G, NSF AST-1009799, and Caltech/JPL SURP Project No. 1515294 through the UT Austin (P.I. Paul Shapiro). MCB acknowledges support from the NSF under AST-1411879. KN acknowledges the partial support by JSPS KAKENHI Grant Number 26247022. Support for HST/STScI AR-12639.01-A was provided by NASA through a grant from the STScI, which is operated by the AURA, Inc., under NASA contract NAS5-26555.