{
  "id": "astro-ph/9912387",
  "version": "v1",
  "published": "1999-12-17T16:57:56.000Z",
  "updated": "1999-12-17T16:57:56.000Z",
  "title": "Eta Carinae: Binarity Confirmed",
  "authors": [
    "Augusto Damineli",
    "Andreas Kaufer",
    "Bernhard Wolf",
    "Otmar Stahl",
    "Dalton F. Lopes",
    "Francisco X. de Araujo"
  ],
  "comment": "13 pages, accepted by ApJ Letters (January 2000)",
  "doi": "10.1086/312441",
  "categories": [
    "astro-ph"
  ],
  "abstract": "We report the recovery of a spectroscopic event in eta Carinae in 1997/98 after a prediction by Damineli (1996). A true periodicity with P = 2020+-5 days (0.2% uncertainty) is obtained. The line intensities and the radial-velocity curve display a phase-locked behavior implying that the energy and dynamics of the event repeat from cycle to cycle. This rules out S Doradus oscillation or multiple shell ejection by an unstable star as the explanation of the spectroscopic events. A colliding-wind binary scenario is supported by our spectroscopic data and by X-ray observations. Although deviations from a simple case exist around periastron, intensive monitoring during the next event (mid 2003) will be crucial to the understanding of the system.",
  "revisions": [
    {
      "version": "v1",
      "updated": "1999-12-17T16:57:56.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "eta carinae",
      "spectroscopic event",
      "radial-velocity curve display",
      "multiple shell ejection"
    ],
    "tags": [
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 13,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 520905
    }
  }
}