{
  "id": "1909.08878",
  "version": "v1",
  "published": "2019-09-19T09:12:39.000Z",
  "updated": "2019-09-19T09:12:39.000Z",
  "title": "Diagnostics of collisions between electrons and water molecules in near-ultraviolet and visible wavelengths",
  "authors": [
    "D. Bodewits",
    "J. Országh",
    "J. Noonan",
    "M. Ďurian",
    "Š. Matejčík"
  ],
  "comment": "9 Figures, 8 Tables",
  "categories": [
    "astro-ph.EP",
    "physics.atom-ph"
  ],
  "abstract": "We studied dissociation reactions of electron impact on water vapor for several fragment species at optical and near ultraviolet wavelengths (200 - 850 nm). The resulting spectrum is dominated by the Hydrogen Balmer series, by the OH (A $^2\\Sigma^+$ - X $^2\\Pi$) band, and by the emission of ionic H$_2$O$^+$ (A $^2$A$_1$ - X $^2$B$_1$) and OH$^+$ (A $^3\\Pi$ - X $^3\\Sigma^-$) band systems. Emission cross sections and reaction channel thresholds were determined for energies between 5 - 100 eV. We find that electron impact dissociation of H$_2$O results in an emission spectrum of the OH (A $^2\\Sigma^+$ - X $^2\\Pi$) band that is distinctly different than the emission spectra from other excitation mechanisms seen in planetary astronomy. We attribute the change to a strongly non-thermal population of rotational states seen in planetary astronomy. This difference can be utilized for remote probing of the contribution of different physical reactions in astrophysical environments.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2019-09-19T09:12:39.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "water molecules",
      "visible wavelengths",
      "planetary astronomy",
      "diagnostics",
      "emission spectrum"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}