{
  "id": "1906.07936",
  "version": "v1",
  "published": "2019-06-19T06:38:48.000Z",
  "updated": "2019-06-19T06:38:48.000Z",
  "title": "Stability of a force-free Hall equilibrium and release of magnetic energy",
  "authors": [
    "Leonid Kitchatinov"
  ],
  "comment": "9 two-column pages, 8 figures, submitted to AN",
  "categories": [
    "astro-ph.SR",
    "physics.flu-dyn",
    "physics.plasm-ph"
  ],
  "abstract": "Conservation of magnetic helicity by the Hall drift does not prevent Hall instability of helical fields. This conclusion follows from stability analysis of a force-free spatially-periodic Hall equilibrium. The growth rates of the instability scale as $\\sigma \\propto B^{3/4}\\eta^{1/4}$ with the field strength $B$ and magnetic diffusivity $\\eta$ and can be large compared to the rate of resistive decay of the background field. The instability deviates the magnetic field from the force-free configuration. The unstable eigenmodes include a fine spatial structure which evolves into current sheets at the nonlinear stage of the instability. The instability catalyses the resistive release of magnetic energy. The energy is released in a sequence of spikes, every spike emits several percent of the total energy. A numerically defined scaling for the energy released in a single spike permits an extrapolation to astrophysically relevant values of the Hall number. The instability can be relevant to magnetic energy release in a neutron star crust and, possibly, in stellar coronae.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2019-06-19T06:38:48.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "magnetic energy",
      "force-free hall equilibrium",
      "force-free spatially-periodic hall equilibrium",
      "fine spatial structure",
      "single spike permits"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}