{
  "id": "1611.03872",
  "version": "v1",
  "published": "2016-11-11T21:00:37.000Z",
  "updated": "2016-11-11T21:00:37.000Z",
  "title": "The density of dark matter haloes of early-type galaxies in low density environments",
  "authors": [
    "E. M. Corsini",
    "G. A. Wegner",
    "J. Thomas",
    "R. P. Saglia",
    "R. Bender"
  ],
  "comment": "26 pages, 6 figures, MNRAS in press",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "New photometric and long-slit spectroscopic observations are presented for NGC 7113, PGC 1852, and PGC 67207, which are three bright galaxies residing in low density environments. The surface-brightness distribution is analysed from K_S-band images taken with adaptive optics at the Gemini North Telescope and ugriz-band images from the Sloan Digital Sky Survey while the line-of-sight stellar velocity distribution and line-strength Lick indices inside the effective radius are measured along several position angles. The age, metallicity, and alpha-element abundance of the galaxies are estimated from single stellar-population models. In spite of the available morphological classification, images show that PGC 1852 is a barred spiral which we do not further consider for mass modelling. The structural parameters of the two early-type galaxies NGC 7113 and PGC 67207 are obtained from a two-dimensional photometric decomposition and the mass-to-light ratio of all the (luminous and dark) mass that follows the light is derived from orbit-based axisymmetric dynamical modelling together with the mass density of the dark matter halo. The dynamically derived mass that follows the light is about a factor 2 larger than the stellar mass derived using stellar-population models with Kroupa initial mass function. Both galaxies have a lower content of halo dark matter with respect to early-type galaxies in high density environments and in agreement with the predictions of semi-analytical models of galaxy formation.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2016-11-11T21:00:37.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "dark matter halo",
      "low density environments",
      "sloan digital sky survey",
      "stellar-population models",
      "line-of-sight stellar velocity distribution"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 26,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}