{
  "id": "astro-ph/0405331",
  "version": "v1",
  "published": "2004-05-17T18:39:42.000Z",
  "updated": "2004-05-17T18:39:42.000Z",
  "title": "Are galactic disks dynamically influenced by dust?",
  "authors": [
    "Ch. Theis",
    "N. Orlova"
  ],
  "comment": "21 pages including 24 figures (some figures degraded in quality), in press in Astronomy & Astrophysics 418, 959(2004), A&A version available at http://www.edpsciences.org/articles/aa/full/2004/18/aa0047/aa0047.html",
  "journal": "Astron.Astrophys. 418 (2004) 959-978",
  "doi": "10.1051/0004-6361:20034047",
  "categories": [
    "astro-ph"
  ],
  "abstract": "Dynamically cold components are well known to destabilize hotter, even much more massive components. In this paper we studied the dynamical influence of a cold dust component on the gaseous phase in the central regions of galactic disks. We performed two-dimensional hydrodynamical simulations for flat multi-component disks embedded in a combined static stellar and dark matter potential. The pressure-free dust component is coupled to the gas by a drag force depending on their velocity difference. It turned out that the most unstable regions are those with either a low or near to minimum Toomre parameter or with rigid rotation, i.e. the central area. In that regions the dust-free disks become most unstable for high azimuthal modes (m~8), whereas in dusty disks all modes have a similar amplitude resulting in a patchy appearance. The structures in the dust have a larger contrast between arm and inter-arm regions than those of the gas. The dust peaks are frequently correlated with peaks of the gas distribution, but they do not necessarily coincide with them. Therefore, a large scatter in the dust-to-gas ratios is expected. The appearance of the dust is more cellular (i.e. sometimes connecting different spiral features), whereas the gas is organized in a multi-armed spiral structure. An admixture of 2% dust destabilizes gaseous disks substantially, whereas dust-to-gas ratios below 1% have no influence on the evolution of the gaseous disk. For a high dust-to-gas ratio of 10% the instabilities reach a saturation level already after 30 Myr.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2004-05-17T18:39:42.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "galactic disks",
      "dust-to-gas ratio",
      "minimum toomre parameter",
      "dust destabilizes gaseous disks"
    ],
    "tags": [
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 21,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 650453
    }
  }
}