{
  "id": "1712.06257",
  "version": "v1",
  "published": "2017-12-18T05:51:22.000Z",
  "updated": "2017-12-18T05:51:22.000Z",
  "title": "Possible $η' d$ bound state and its $s$-channel formation in the $γd \\to ηd$ reaction",
  "authors": [
    "Takayasu Sekihara",
    "Hiroyuki Fujioka",
    "Takatsugu Ishikawa"
  ],
  "comment": "9 pages, 13 eps figures",
  "categories": [
    "nucl-th",
    "hep-ex",
    "hep-ph",
    "nucl-ex"
  ],
  "abstract": "We theoretically investigate a possibility of an $\\eta ^{\\prime} d$ bound state and its formation in the $\\gamma d \\to \\eta d$ reaction. First, in the fixed center approximation to the Faddeev equations we obtain an $\\eta ^{\\prime} d$ bound state with a binding energy of 25 MeV and width of 19 MeV, where we take the $\\eta ^{\\prime} N$ interaction with a coupling to the $\\eta N$ channel from the linear $\\sigma$ model. Then, in order to investigate the feasibility from an experimental point of view, we calculate the cross section of the $\\gamma d \\to \\eta d$ reaction at the photon energy in the laboratory frame around 1.2 GeV. As a result, we find a clear peak structure with the strength $\\sim$ 0.2 nb/sr, corresponding to a signal of the $\\eta ^{\\prime} d$ bound state in case of backward $\\eta$ emission. This structure will be prominent because a background contribution coming from single-step $\\eta$ emission off a bound nucleon is highly suppressed. In addition, the signal can be seen even in case of forward $\\eta$ emission as a bump or dip, depending on the relative phase between the bound-state formation and the single-step background.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2017-12-18T05:51:22.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "bound state",
      "channel formation",
      "clear peak structure",
      "fixed center approximation",
      "background contribution"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 9,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}