Paper  astro-ph/0508046

The many lives of AGN: cooling flows, black holes and the luminosities and colours of galaxies

Authors: Darren J. Croton (1), Volker Springel (1), Simon D. M. White (1), Gabriella De Lucia (1), Carlos S. Frenk (2), Liang Gao (1), Adrian Jenkins (2), Guinevere Kauffmann (1), Julio Navarro (3), Naoki Yoshida (4) ((1) MPA, (2) Durham, (3) UVic, (4) Nagoya)
Comments: 21 pages, 12 figures, MNRAS (submitted). High resolution PDF version available on this page. Millennium Run semi-analytic galaxy catalogues are available for download on this page.
We simulate the growth of galaxies and their central supermassive black holes by implementing a suite of semi-analytic models on the output of the Millennium Run, a very large simulation of the concordance LCDM cosmogony. Our procedures follow the detailed assembly history of each object and are able to track the evolution of all galaxies more massive than the Small Magellanic Cloud throughout a volume comparable to that of large modern redshift surveys. In this first paper we supplement previous treatments of the growth and activity of central black holes with a new model for `radio' feedback from those AGN that lie at the centre of a quasistatic X-ray emitting atmosphere in a galaxy group or cluster. We show that for energetically and observationally plausible parameters such a model can simultaneously explain: (i) the low observed mass drop-out rate in cooling flows; (ii) the exponential cut-off at the bright end of the galaxy luminosity function; and (iii) the fact that the most massive galaxies tend to be bulge-dominated systems in clusters and to contain systematically older stars than lower mass galaxies. This success occurs because static hot atmospheres form only in the most massive structures, and radio feedback (in contrast, for example, to supernova or starburst feedback) can suppress further cooling and star formation without itself requiring star formation. We discuss possible physical models which might explain the accretion rate scalings required for our phenomenological `radio mode' model to be successful.

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Millennium Run semi-analytic galaxy catalogue downloads

(See also: Download site for full halo and semi-analytic galaxy catalogues)

The Millennium Run LCDM N-body simulation is described in the Nature paper "Simulating the joint evolution of quasars, galaxies and their large-scale distribution" (Springel et al. 2005). Full details, along with images and movies of the simulation, can be found here.

  • The semi-analytic catalogue can be downloaded by clicking the appropriate link on the right.

  • Galaxy magnitudes are available in both BVRIK (Vega) or ugriz (AB SDSS) filters.

  • Catalogues only include galaxies above our magnitude completeness limit (M_r-5logh = -16.6 (SDSS) and M_B-5logh = -15.6), for a total of about 9 million galaxies in the full simulation box (500 Mpc/h on a side).

  • The galaxies are stored as either a binary structure (~650 Mb, IDL script included) or in ASCII format (~1 Gb).

  • A "mini" version of the catalogue is also available for testing purposes (<2 Mb), which is identical in every way to the full version but in a smaller periodic box of 62.5 Mpc/h on a side.

  • The following redshift zero information is available for each galaxy:
    galaxy position and velocity,
    total and bulge galaxy magnitude in 5 bands,
    total and bulge stellar mass,
    cold, hot and ejected gas mass,
    black hole mass,
    star formation rate.
  • Please acknowledge the use of this galaxy catalogue with the following:
    "The Millennium Run simulation used in this paper was carried out by the Virgo Supercomputing Consortium at the Computing Centre of the Max-Planck Society in Garching. The semi-analytic galaxy catalogue is publicly available at"
  • Additional instructions are included in the tarfile. Please email here with any questions. Further galaxy properties can be made available. A formal request, together with a brief summary of the proposed project, should be sent to Simon White here.

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    Last modified: August 3, 2005