{
  "id": "1412.2883",
  "version": "v1",
  "published": "2014-12-09T08:25:35.000Z",
  "updated": "2014-12-09T08:25:35.000Z",
  "title": "Properties of barred spiral disks in hydrodynamical cosmological simulations",
  "authors": [
    "Goz David",
    "Pierluigi Monaco",
    "Giuseppe Murante",
    "Anna Curir"
  ],
  "comment": "15 pages, 18 figures, MNRAS accepted",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "We present a quantification of the properties of bars in two N-body+SPH cosmological simulations of spiral galaxies, named GA and AqC. The initial conditions were obtained using the zoom-in technique and represent two dark matter (DM) halos of $2-3\\times10^{12}\\ {\\rm M}_\\odot$, available at two different resolutions. The resulting galaxies are presented in the companion paper of Murante et al. (2014). We find that the GA galaxy has a bar of length $8.8$ kpc, present at the two resolution levels even though with a slightly different strength. Classical bar signatures (e.g. pattern of streaming motions, high $m=2$ Fourier mode with roughly constant phase) are consistently found at both resolutions. Though a close encounter with a merging satellite at $z\\sim0.6$ (mass ratio $1:50$) causes a strong, transient spiral pattern and some heating of the disk, we find that bar instability is due to secular process, caused by a low Toomre parameter $Q\\lesssim1$ due to accumulation of mass in the disk. The AqC galaxy has a slightly different history: it suffers a similar tidal disturbance due to a merging satellite at $z\\sim0.5$ but with a mass ratio of $1:32$, that triggers a bar in the high-resolution simulation, while at low resolution the merging is found to take place at a later time, so that both secular evolution and merging are plausible triggers for bar instability.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2014-12-09T08:25:35.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "barred spiral disks",
      "hydrodynamical cosmological simulations",
      "properties",
      "bar instability",
      "mass ratio"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 15,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}