{
  "id": "1807.09806",
  "version": "v1",
  "published": "2018-07-25T18:15:56.000Z",
  "updated": "2018-07-25T18:15:56.000Z",
  "title": "Young and eccentric: the quadruple system HD 86588",
  "authors": [
    "Andrei Tokovinin",
    "Hank Corbett",
    "Octavi Fors",
    "Ward Howard",
    "Nicholas M. Law",
    "Maxwell Moe",
    "Frederick M. Walter"
  ],
  "comment": "Accepted by The Astronomical Journal; 10 pages, 9 figures",
  "categories": [
    "astro-ph.SR"
  ],
  "abstract": "High-resolution spectroscopy and speckle interferometry reveal the young star HD 86588 as a quadruple system with a 3-tier hierarchy. The 0.3\" resolved binary A,B with an estimated period around 300 years contains the 8-year pair Aa,Abc (also potentially resolvable), where Ab,Ac is a double-lined binary with equal components, for which we compute the spectroscopic orbit. Despite the short period of 2.4058 day, the orbit of Ab,Ac is eccentric (e=0.086+-0.003). It has a large inclination, but there are no eclipses; only a 4.4 mmag light modulation apparently caused by star spots on the components of this binary is detected with Evryscope. Assuming a moderate extinction of A_V = 0.5 mag and a parallax of 5.2 mas, we find that the stars are on or close to the main sequence (age >10 Myr) and their masses are from 1 to 1.3 solar. We measure the strength of the Lithium line in the visual secondary B which, together with rotation, suggests that the system is younger than 150 Myr. This object is located behind the extension of the Chamaeleon I dark cloud (which explains extinction and interstellar Sodium absorption), but apparently does not belong to it. We propose a scenario where the inner orbit has recently acquired its high eccentricity through dynamical interaction with the outer two components; it is now undergoing rapid tidal circularization on a time scale of ~1 Myr. Alternatively, the eccentricity could be excited quasi-stationary by the outer component Aa.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2018-07-25T18:15:56.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "quadruple system hd",
      "undergoing rapid tidal circularization",
      "outer component aa",
      "speckle interferometry reveal",
      "interstellar sodium absorption"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 10,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}