{
  "id": "0908.1120",
  "version": "v1",
  "published": "2009-08-07T20:43:50.000Z",
  "updated": "2009-08-07T20:43:50.000Z",
  "title": "The Globular Cluster System in M87: A Wide-Field Study with CFHT/Megacam",
  "authors": [
    "William E. Harris"
  ],
  "comment": "23 pages, 11 figures, accepted for publication in Astrophysical Journal",
  "categories": [
    "astro-ph.GA",
    "astro-ph.CO"
  ],
  "abstract": "CFHT Megacam data in (g',r',i') are used to obtain deep, wide-field photometry of the globular cluster system (GCS) around M87. A total of 6200 GCs brighter than M_I = -8.5 are included in the study, essentially containing almost the entire bright half of the total GC population in the galaxy. The classic bimodal metal-poor and metal-rich sequences of GCs show up clearly; while the spatial distribution of the GCs can be traced detectably outward to more than 100 kpc, the blue, metal-poor subpopulation is very much more spatially extended than the red subpopulation. Both the red and blue GC subsystems have radial metallicity gradients, where mean heavy-element abundance scales with projected galactocentric distance as Z ~ R^{-0.12} (blue) and R^{-0.17} (red). The blue sequence exhibits a strongly significant mass/metallicity relation (MMR) in which the mean metallicity gradually increases with cluster luminosity as Z ~ L^{0.25 \\pm 0.05} for the luminosity range M_I < -10. However, this relation is also clearly nonlinear, becoming vertical at fainter levels. The MMR can be understood as the result of self-enrichment within the most massive metal-poor GCs during their formation. In giant elliptical galaxies, the red GCs are likely to represent a broad composite population formed during several major starbursts. If so, the red sequence might display a population-based MMR that could in principle be either positive or negative.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2009-08-07T20:43:50.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "globular cluster system",
      "wide-field study",
      "mean heavy-element abundance scales",
      "cfht/megacam",
      "radial metallicity gradients"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1088/0004-637X/703/1/939",
      "journal": "The Astrophysical Journal",
      "year": 2009,
      "month": "Sep",
      "volume": 703,
      "number": 1,
      "pages": 939
    },
    "note": {
      "typesetting": "TeX",
      "pages": 23,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 828118,
      "adsabs": "2009ApJ...703..939H"
    }
  }
}