{
  "id": "1112.2151",
  "version": "v1",
  "published": "2011-12-09T17:13:36.000Z",
  "updated": "2011-12-09T17:13:36.000Z",
  "title": "Prospects for Probing the Spacetime of Sgr A* with Pulsars",
  "authors": [
    "K. Liu",
    "N. Wex",
    "M. Kramer",
    "J. M. Cordes",
    "T. J. W. Lazio"
  ],
  "comment": "12 pages, 10 Figures, accepted for publication in ApJ",
  "categories": [
    "astro-ph.HE",
    "astro-ph.GA"
  ],
  "abstract": "The discovery of radio pulsars in compact orbits around Sgr A* would allow an unprecedented and detailed investigation of the spacetime of the supermassive black hole. This paper shows that pulsar timing, including that of a single pulsar, has the potential to provide novel tests of general relativity, in particular its cosmic censorship conjecture and no-hair theorem for rotating black holes. These experiments can be performed by timing observations with 100 micro-second precision, achievable with the Square Kilometre Array for a normal pulsar at frequency above 15 GHz. Based on the standard pulsar timing technique, we develop a method that allows the determination of the mass, spin, and quadrupole moment of Sgr A*, and provides a consistent covariance analysis of the measurement errors. Furthermore, we test this method in detailed mock data simulations. It seems likely that only for orbital periods below ~0.3 yr is there the possibility of having negligible external perturbations. For such orbits we expect a ~10^-3 test of the frame dragging and a ~10^-2 test of the no-hair theorem within 5 years, if Sgr A* is spinning rapidly. Our method is also capable of identifying perturbations caused by distributed mass around Sgr A*, thus providing high confidence in these gravity tests. Our analysis is not affected by uncertainties in our knowledge of the distance to the Galactic center, R0. A combination of pulsar timing with the astrometric results of stellar orbits would greatly improve the measurement precision of R0.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2011-12-09T17:13:36.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "black hole",
      "no-hair theorem",
      "detailed mock data simulations",
      "standard pulsar timing technique",
      "consistent covariance analysis"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1088/0004-637X/747/1/1",
      "journal": "The Astrophysical Journal",
      "year": 2012,
      "month": "Mar",
      "volume": 747,
      "number": 1,
      "pages": 1
    },
    "note": {
      "typesetting": "TeX",
      "pages": 12,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1080808,
      "adsabs": "2012ApJ...747....1L"
    }
  }
}