{
  "id": "0807.3911",
  "version": "v1",
  "published": "2008-07-24T15:21:56.000Z",
  "updated": "2008-07-24T15:21:56.000Z",
  "title": "Tracing Galaxy Formation with Stellar Halos II: Relating Substructure in Phase- and Abundance-Space to Accretion Histories",
  "authors": [
    "Kathryn V. Johnston",
    "James S. Bullock",
    "Sanjib Sharma",
    "Andreea Font",
    "Brant E. Robertson",
    "Samuel N. Leitner"
  ],
  "comment": "21 pages, 20 figures. To appear in the Astrophysical Journal",
  "doi": "10.1086/592228",
  "categories": [
    "astro-ph"
  ],
  "abstract": "This paper explores the mapping between the observable properties of a stellar halo in phase- and abundance-space and the parent galaxy's accretion history in terms of the characteristic epoch of accretion and mass and orbits of progenitor objects. The study utilizes a suite of eleven stellar halo models constructed within the context of a standard LCDM cosmology. The results demonstrate that coordinate-space studies are sensitive to the recent (0-8 Gyears ago) merger histories of galaxies (this timescale corresponds to the last few to tens of percent of mass accretion for a Milky-Way-type galaxy). Specifically, the {\\it frequency, sky coverage} and {\\it fraction of stars} in substructures in the stellar halo as a function of surface brightness are indicators of the importance of recent merging and of the luminosity function of infalling dwarfs. The {\\it morphology} of features serves as a guide to the orbital distribution of those dwarfs. Constraints on the earlier merger history (> 8 Gyears ago) can be gleaned from the abundance patterns in halo stars: within our models, dramatic differences in the dominant epoch of accretion or luminosity function of progenitor objects leave clear signatures in the [alpha/Fe] and [Fe/H] distributions of the stellar halo - halos dominated by very early accretion have higher average [alpha/Fe], while those dominated by high luminosity satellites have higher [Fe/H]. This intuition can be applied to reconstruct much about the merger histories of nearby galaxies from current and future data sets.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2008-07-24T15:21:56.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "stellar halo",
      "tracing galaxy formation",
      "relating substructure",
      "merger history",
      "abundance-space"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "journal": "The Astrophysical Journal",
      "year": 2008,
      "month": "Dec",
      "volume": 689,
      "number": 2,
      "pages": 936
    },
    "note": {
      "typesetting": "TeX",
      "pages": 21,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 791438,
      "adsabs": "2008ApJ...689..936J"
    }
  }
}