{
  "id": "1011.3563",
  "version": "v2",
  "published": "2010-11-16T01:20:52.000Z",
  "updated": "2011-01-21T02:17:53.000Z",
  "title": "The spin parameter of uniformly rotating compact stars",
  "authors": [
    "Ka-Wai Lo",
    "Lap-Ming Lin"
  ],
  "comment": "Minor changes to match the published version",
  "journal": "Astrophys.J.728:12,2011",
  "categories": [
    "astro-ph.HE",
    "gr-qc"
  ],
  "abstract": "We study the dimensionless spin parameter $j (= c J/ (G M^2))$ of uniformly rotating neutron stars and quark stars in general relativity. We show numerically that the maximum value of the spin parameter of a neutron star rotating at the Keplerian frequency is $j_{\\rm max} \\sim 0.7$ for a wide class of realistic equations of state. This upper bound is insensitive to the mass of the neutron star if the mass of the star is larger than about $1 M_\\odot$. On the other hand, the spin parameter of a quark star modeled by the MIT bag model can be larger than unity and does not have a universal upper bound. Its value also depends strongly on the bag constant and the mass of the star. Astrophysical implications of our finding will be discussed.",
  "revisions": [
    {
      "version": "v2",
      "updated": "2011-01-21T02:17:53.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "spin parameter",
      "uniformly rotating compact stars",
      "neutron star",
      "quark star",
      "mit bag model"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1088/0004-637X/728/1/12",
      "journal": "The Astrophysical Journal",
      "year": 2011,
      "month": "Feb",
      "volume": 728,
      "number": 1,
      "pages": 12
    },
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 877514,
      "adsabs": "2011ApJ...728...12L"
    }
  }
}