{
  "id": "1511.00018",
  "version": "v1",
  "published": "2015-10-30T20:08:13.000Z",
  "updated": "2015-10-30T20:08:13.000Z",
  "title": "Feedback Regulated Turbulence, Magnetic Fields, and Star Formation Rates in Galactic Disks",
  "authors": [
    "Chang-Goo Kim",
    "Eve C. Ostriker"
  ],
  "comment": "To appear in Proceedings of IAU Symposium 315, From interstellar clouds to star-forming galaxies: universal processes?, P. Jablonka, P. Andre, and F.. van der Tak, eds",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "We use three-dimensional magnetohydrodynamic (MHD) simulations to investigate the quasi-equilibrium states of galactic disks regulated by star formation feedback. We incorporate effects from massive-star feedback via time-varying heating rates and supernova (SN) explosions. We find that the disks in our simulations rapidly approach a quasi-steady state that satisfies vertical dynamical equilibrium. The star formation rate (SFR) surface density self-adjusts to provide the total momentum flux (pressure) in the vertical direction that matches the weight of the gas. We quantify feedback efficiency by measuring feedback yields, \\eta_c\\equiv P_c/\\Sigma_SFR (in suitable units), for each pressure component. The turbulent and thermal feedback yields are the same for HD and MHD simulations, \\eta_th~1 and \\eta_ turb~4, consistent with the theoretical expectations. In MHD simulations, turbulent magnetic fields are rapidly generated by turbulence, and saturate at a level corresponding to \\eta_mag,t~1. The presence of magnetic fields enhances the total feedback yield and therefore reduces the SFR, since the same vertical support can be supplied at a smaller SFR. We suggest further numerical calibrations and observational tests in terms of the feedback yields.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2015-10-30T20:08:13.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "star formation rate",
      "feedback regulated turbulence",
      "galactic disks",
      "mhd simulations",
      "turbulent magnetic fields"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}