{
  "id": "1709.05044",
  "version": "v1",
  "published": "2017-09-15T03:33:36.000Z",
  "updated": "2017-09-15T03:33:36.000Z",
  "title": "New binaries in the epsilon Cha association",
  "authors": [
    "Cesar Briceno",
    "Andrei Tokovinin"
  ],
  "comment": "12 pages, 6 figures. Accepted for publication in The Astronomical Journal",
  "categories": [
    "astro-ph.SR"
  ],
  "abstract": "We present Adaptive Optics-aided speckle observations of 47 young stars in the $\\epsilon$ Cha association, made at the 4-m Southern Astrophysical Research Telescope in the $I$-band. We resolved 10 new binary pairs, 5 previously known binaries and two triple systems, also previously known. In the separation range between 4 and 300 AU, the 30 association members of spectral types G0 and later host 6 binary companions, leading to the raw companion frequency of $0.010\\pm0.04$ per decade of separation, comparable to the main sequence dwarfs in the field. On the other hand, all 5 massive association members of spectral types A and B have companions in this range. We discuss the newly resolved and known binaries in our sample. Observed motions in the triple system $\\epsilon$ Cha, composed of three similar B9V stars, can be described by tentative orbits with periods 13 and $\\sim 900$ years, and a large mutual inclination.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2017-09-15T03:33:36.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "epsilon cha association",
      "triple system",
      "main sequence dwarfs",
      "similar b9v stars",
      "spectral types g0"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 12,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}