{
  "id": "2103.02113",
  "version": "v1",
  "published": "2021-03-03T01:14:45.000Z",
  "updated": "2021-03-03T01:14:45.000Z",
  "title": "The Color and Brightness of the F-Corona Inferred from the 2019 July 2 Total Solar Eclipse",
  "authors": [
    "Benjamin Boe",
    "Shadia Habbal",
    "Cooper Downs",
    "Miloslav Druckmuller"
  ],
  "comment": "25 pages, 9 figures, accepted for publication in ApJ",
  "categories": [
    "astro-ph.SR"
  ],
  "abstract": "Total solar eclipses (TSEs) provide a unique opportunity to quantify the properties of the K-corona (electrons), F-corona (dust) and E-corona (ions) continuously from the solar surface out to a few solar radii. We apply a novel inversion method to separate emission from the K- and F-corona continua using unpolarized total brightness (tB) observations from five 0.5 nm bandpasses acquired during the 2019 July 2 TSE between 529.5 nm and 788.4 nm. The wavelength dependence relative to the photosphere (i.e., color) of the F-corona itself is used to infer the tB of the K- and F-corona for each line-of-sight. We compare our K-corona emission results with the Mauna Loa Solar Observatory (MLSO) K-Cor polarized brightness (pB) observations from the day of the eclipse, and the forward modeled K-corona intensity from the Predictive Science Inc. (PSI) Magnetohydrodynamic (MHD) model prediction. Our results are generally consistent with previous work and match both the MLSO data and PSI-MHD predictions quite well, supporting the validity of our approach and of the PSI-MHD model. However, we find that the tB of the F-corona is higher than expected in the low corona, perhaps indicating that the F-corona is slightly polarized -- challenging the common assumption that the F-corona is entirely unpolarized.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2021-03-03T01:14:45.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "total solar eclipse",
      "brightness",
      "mauna loa solar observatory",
      "k-corona emission results",
      "novel inversion method"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 25,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}