{
  "annotation_id": "d663c660-1e07-4230-a8a5-ffbb48f68472",
  "date_created": "2026-03-02T18:01:20.933000Z",
  "date_modified": "2026-03-02T18:01:20.933000Z",
  "file_hash": "7b18423a99a6109a5d0c670a8c1f54000748cffa16ecae9213b6c54bc7f47c10",
  "private": false,
  "record": {
    "abstract": "A non-relativistic Fokker-Planck equation for the electron distribution\nfunction is formulated incorporating the effects of stochastic acceleration by\nwhistler-mode waves and Coulomb collisions. The stationary solution $f$ to the\nequation, subject to a zero-flux boundary condition, is found to be a\ngeneralized Lorentzian (or kappa) distribution, which satisfies $f\\propto\nv^{-2(\\kappa+1)}$ for large velocity $v$, where $\\kappa$ is the spectral index.\nThe parameter $\\kappa$ depends strongly on the relative wave intensity $R$.\nTaking into account the critical energy required for resonance of electrons\nwith whistlers, we calculate a range of values of $R$ for each of a number of\ndifferent space plasmas for which kappa distributions can be expected to be\nformed. This study is one of the first in the literature to provide a\ntheoretical justification for the formation of generalized Lorentzian (or\nkappa) particle distribution functions in space plasmas.",
    "arxiv_id": "physics/9810049",
    "authors": [
      "Chun-yu Ma",
      "Danny Summers"
    ],
    "categories": [
      "physics.plasm-ph",
      "astro-ph",
      "physics.space-ph"
    ],
    "doi": "10.1029/1998GL900108",
    "journal_ref": "Geophysical Research Letters 25, No.21, 4099, 1998",
    "title": "Formation of Power-law Energy Spectra in Space Plasmas by Stochastic   Acceleration due to Whistler-Mode Waves",
    "url": "https://arxiv.org/abs/physics/9810049"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "807eac8b-9aa2-4a28-98fb-9d8e4708154a",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}