{
  "id": "1802.03842",
  "version": "v1",
  "published": "2018-02-11T23:52:46.000Z",
  "updated": "2018-02-11T23:52:46.000Z",
  "title": "Circular polarization of gravitational waves from non-rotating supernova cores: a new probe into the pre-explosion hydrodynamics",
  "authors": [
    "Kazuhiro Hayama",
    "Takami Kuroda",
    "Kei Kotake",
    "Tomoya Takiwaki"
  ],
  "comment": "5 pages, 4 figures",
  "categories": [
    "astro-ph.HE",
    "gr-qc"
  ],
  "abstract": "We present an analysis of the circular polarization of gravitational-waves (GWs) using results from three-dimensional (3D), general relativistic (GR) core-collapse simulations of a non-rotating $15 M_{\\odot}$ star. For the signal detection, we perform a coherent network analysis taking into account the four interferometers of LIGO Hanford, LIGO Livingston, VIRGO, and KAGRA. We focus on the Stokes $V$ parameter, which directly characterizes the asymmetry of the GW circular polarization. We find that the amplitude of the GW polarization becomes bigger for our 3D-GR model that exhibits strong activity of the standing accretion shock instability (SASI). Our results suggest that the SASI-induced accretion flows to the proto-neutron star (PNS) lead to a characteristic, low-frequency modulation (100 $\\sim$ 200 Hz) in both the waveform and the GW circular polarization. During the vigorous SASI phase, we observe that the GW polarization switches from the right- to left-handed mode, which is clearly visible in the spectrogram. By estimating the signal-to-noise ratio of the GW polarization, we demonstrate that the detection horizon of the circular polarization extends by more than a factor of several times farther comparing to that of the GW amplitude. Our results suggest that the GW circular polarization, if detected, could provide a new probe into the pre-explosion hydrodynamics such as the SASI activity and the $g$-mode oscillation of the PNS.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2018-02-11T23:52:46.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "non-rotating supernova cores",
      "pre-explosion hydrodynamics",
      "gw circular polarization",
      "gravitational waves",
      "standing accretion shock instability"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 5,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}