Black hole–galaxy scaling relations in FIRE: the importance of black hole location and mergers
ABSTRACT

The concurrent growth of supermassive black holes (SMBHs) and their host galaxies remains to be fully explored, especially at high redshift. While often understood as a consequence of self-regulation via AGN feedback, it can also be explained by alternative SMBH accretion models. Here, we expand on previous work by studying the growth of SMBHs with the help of a large suite of cosmological zoom-in simulations (MassiveFIRE) that are part of the Feedback in Realistic Environments (FIRE) project. The growth of SMBHs is modelled in post-processing with different black hole accretion models, placements, and merger treatments, and validated by comparing to on-the-fly calculations. Scaling relations predicted by the gravitational torque-driven accretion (GTDA) model agree with observations at low redshift without the need for AGN feedback, in contrast to models in which the accretion rate depends strongly on SMBH mass. At high redshift, we find deviations from the local scaling relations in line with previous theoretical results. In particular, SMBHs are undermassive, presumably due to stellar feedback, but start to grow efficiently once their host galaxies reach M* ∼ 1010M⊙. We analyse and explain these findings in the context of a simple analytic model. Finally, we show that the predicted scaling more »

Authors:
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Award ID(s):
Publication Date:
NSF-PAR ID:
10362447
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
511
Issue:
1
Page Range or eLocation-ID:
p. 506-535
ISSN:
0035-8711
Publisher:
Oxford University Press
National Science Foundation
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2. ABSTRACT

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3. ABSTRACT

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5. ABSTRACT

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