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A semi-analytic model for the co-evolution of galaxies, black holes and active galactic nuclei

Somerville, Rachel S. and Hopkins, Philip F. and Cox, Thomas J. and Robertson, Brant E. and Hernquist, Lars (2008) A semi-analytic model for the co-evolution of galaxies, black holes and active galactic nuclei. Monthly Notices of the Royal Astronomical Society, 391 (2). pp. 481-506. ISSN 0035-8711.

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We present a new semi-analytic model that self-consistently traces the growth of supermassive black holes (BH) and their host galaxies within the context of the Lambda cold dark matter (ΛCDM) cosmological framework. In our model, the energy emitted by accreting black holes regulates the growth of the black holes themselves, drives galactic scale winds that can remove cold gas from galaxies, and produces powerful jets that heat the hot gas atmospheres surrounding groups and clusters. We present a comprehensive comparison of our model predictions with observational measurements of key physical properties of low-redshift galaxies, such as cold gas fractions, stellar metallicities and ages, and specific star formation rates. We find that our new models successfully reproduce the exponential cut-off in the stellar mass function and the stellar and cold gas mass densities at z∼ 0, and predict that star formation should be largely, but not entirely, quenched in massive galaxies at the present day. We also find that our model of self-regulated BH growth naturally reproduces the observed relation between BH mass and bulge mass. We explore the global formation history of galaxies and black holes in our models, presenting predictions for the cosmic histories of star formation, stellar mass assembly, cold gas and metals. We find that models assuming the ‘concordance’ΛCDM cosmology overproduce star formation and stellar mass at high redshift (z≳ 2). A model with less small-scale power predicts less star formation at high redshift, and excellent agreement with the observed stellar mass assembly history, but may have difficulty accounting for the cold gas in quasar absorption systems at high redshift (z∼ 3–4).

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Hopkins, Philip F.0000-0003-3729-1684
Robertson, Brant E.0000-0002-4271-0364
Hernquist, Lars0000-0001-6950-1629
Additional Information:© 2008 The Authors. Journal compilation © 2008 RAS. Accepted 2008 August 5. Received 2008 July 18; in original form 2008 February 25. We would like to thank E. Bell, B. Panter and D. Schiminovich for providing us with their data in electronic form. We warmly thank B. Allgood, E. Bell, J. Bromley, D. Croton, G. de Lucia, A. Dekel, M. Elvis, S. Faber, A. Fabian, S. Jester, A. Kravtsov, C. Martin, L. Moustakas, P. Natarajan, H.-W. Rix, S. Trager, R. Wechsler and A. Walen for discussions that contributed to this work, and S. Allen, A. Gonzalez and S. Zibetti for help interpreting their observational results. We also thank E. Bell and S. Trager for careful readings of an earlier draft of the manuscript, and B. Moster for providing us with his results in advance of publication. RSS thanks the ITC at the CfA for hospitality. BER gratefully acknowledges support from a Spitzer Fellowship through a NASA grant administrated by the Spitzer Science Center. This work was supported in part by a grant from the W. M. Keck Foundation.
Group:Infrared Processing and Analysis Center (IPAC)
Funding AgencyGrant Number
NASA Spitzer FellowshipUNSPECIFIED
W. M. Keck FoundationUNSPECIFIED
Subject Keywords:galaxies: evolution, galaxies: formation, cosmology: theory
Issue or Number:2
Record Number:CaltechAUTHORS:20200529-093432282
Persistent URL:
Official Citation:Rachel S. Somerville, Philip F. Hopkins, Thomas J. Cox, Brant E. Robertson, Lars Hernquist, A semi-analytic model for the co-evolution of galaxies, black holes and active galactic nuclei, Monthly Notices of the Royal Astronomical Society, Volume 391, Issue 2, December 2008, Pages 481–506,
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:103547
Deposited By: George Porter
Deposited On:01 Jun 2020 14:14
Last Modified:01 Jun 2020 14:14

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