{
  "id": "1601.07907",
  "version": "v1",
  "published": "2016-01-28T21:00:04.000Z",
  "updated": "2016-01-28T21:00:04.000Z",
  "title": "It's not easy being green: The evolution of galaxy colour in the EAGLE simulation",
  "authors": [
    "James. W. Trayford",
    "Tom Theuns",
    "Richard G. Bower",
    "Robert A. Crain",
    "Claudia del P. Lagos",
    "Matthieu Schaller",
    "Joop Schaye"
  ],
  "comment": "15 pages, 10 figures. Submitted to MNRAS. All comments welcome. Larger version of Fig. 1 included in source. For the animated evolution of the EAGLE intrinsic u-r CMD (with central and satellite galaxies coloured red and blue respectively) see http://community.dur.ac.uk/j.w.trayford/media/CMD_evolution_EAGLE.mp4",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "We examine the evolution of intrinsic u-r colours of galaxies in the EAGLE cosmological hydrodynamical simulations, which has been shown to reproduce the observed redshift z=0.1 colour-magnitude distribution well. The median u-r of star-forming ('blue cloud') galaxies reddens by 1 mag from z=2 to 0 at fixed stellar mass, as their specific star formation rates decrease with time. A red sequence starts to build-up around z=1, due to the quenching of low-mass satellite galaxies at the faint end, and due to the quenching of more massive central galaxies by their active galactic nuclei (AGN) at the bright end. This leaves a dearth of intermediate-mass red sequence galaxies at z=1, which is mostly filled in by z=0. We quantify the time-scales of colour transition due to satellite and AGN quenching, finding that most galaxies spend less than 2 Gyr in the 'green valley'. On examining the trajectories of galaxies in a colour-stellar mass diagram, we identify three characteristic tracks that galaxies follow (quiescently star-forming, quenching and rejuvenating galaxies) and quantify the fraction of galaxies that follow each track.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2016-01-28T21:00:04.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "eagle simulation",
      "galaxy colour",
      "specific star formation rates decrease",
      "intermediate-mass red sequence galaxies",
      "colour-stellar mass diagram"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 15,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2016arXiv160107907T"
    }
  }
}