{
  "id": "1504.07735",
  "version": "v1",
  "published": "2015-04-29T06:41:48.000Z",
  "updated": "2015-04-29T06:41:48.000Z",
  "title": "Resonant states of neutron-rich $Λ$ hypernucleus $^7_Λ$He",
  "authors": [
    "E. Hiyama",
    "M. Isaka",
    "M. Kamimura",
    "T. Myo",
    "T. Motoba"
  ],
  "comment": "6 pages, 4 figures,published in Physical Review C",
  "categories": [
    "nucl-th"
  ],
  "abstract": "The structure of neutron-rich $\\Lambda$ hypernucleus, $^7_{\\Lambda}$He is studied within the framework of an $\\alpha +\\Lambda +n+n$ four-body cluster model. We predict second $3/2^+$ and $5/2^+$ states, corresponding to a $0s$ $\\Lambda$ coupled to the second $2^+$ state of $^6$He, as narrow resonant states with widths $\\Gamma \\sim 1$ MeV to be at 0.03 MeV and 0.07 MeV respect to the $\\alpha +\\Lambda +n+n$ threshold. From an estimation of the differential cross section for the $^7{\\rm Li} (\\gamma,K^+) ^7_{\\Lambda}$He reaction, there is a possibility to observe these state at JLab in the future. We also calculate the second $2^+$ state of $^6$He as resonant state within the framework of an $\\alpha +n+n$ three-body cluster model. Our result is $2.81$ MeV with $\\Gamma =$4.63 MeV with respect to the $\\alpha +n+n$ threshold. This energy position is $\\sim 1$ MeV higher, and with a much broader decay width, than the recent SPIRAL data. It is suggested that an experiment at JLab to search for the second $3/2^+$ and $5/2^+$ states of $^7_{\\Lambda}$He would provide an opportunity to confirm the second $2^+$ state of the core nucleus $^6$He.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2015-04-29T06:41:48.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "21.80.+a",
      "21.60.Gx",
      "27.20.+n"
    ],
    "keywords": [
      "hypernucleus",
      "neutron-rich",
      "narrow resonant states",
      "four-body cluster model",
      "differential cross section"
    ],
    "publication": {
      "doi": "10.1103/PhysRevC.91.054316"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 6,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1365339
    }
  }
}