{
  "id": "2103.09511",
  "version": "v1",
  "published": "2021-03-17T09:00:05.000Z",
  "updated": "2021-03-17T09:00:05.000Z",
  "title": "Three-body description of $^9$C: Role of low-lying resonances in breakup reactions",
  "authors": [
    "Jagjit Singh",
    "Takuma Matsumoto",
    "Tokuro Fukui",
    "Kazuyuki Ogata"
  ],
  "comment": "7 pages, 4 figures, 2 tables",
  "categories": [
    "nucl-th",
    "nucl-ex"
  ],
  "abstract": "The $^9$C nucleus and related capture reaction, ${^8\\mathrm{B}}(p,\\gamma){^9\\mathrm{C}}$, have been intensively studied with an astrophysical interest. Due to the weakly-bound nature of $^9$C, its structure is likely to be described as the three-body (${^7\\mathrm{Be}}+p+p$). Its continuum structure is also important to describe reaction processes of $^9$C, with which the reaction rate of the ${^8\\mathrm{B}}(p,\\gamma){^9\\mathrm{C}}$ process have been extracted indirectly. We preform three-body calculations on $^9$C and discuss properties of its ground and low-lying states via breakup reactions. We employ the three-body model of $^9$C using the Gaussian-expansion method combined with the complex-scaling method. This model is implemented in the four-body version of the continuum-discretized coupled-channels method, by which breakup reactions of $^9$C are studied. The intrinsic spin of $^7$Be is disregarded. By tuning a three-body interaction in the Hamiltonian of $^9$C, we obtain the low-lying 2$^+$ state with the resonant energy 0.781 MeV and the decay width 0.137 MeV, which is consistent with the available experimental information. Our calculation predicts also three 1$^-$ states. We discuss the role of these resonances in the elastic breakup cross section of $^9$C on $^{208}$Pb at 65 and 160 MeV/A. The low-lying 2$^+$ state is probed as a sharp peak of the breakup cross section, while the 1$^-$ states enhance the cross section around 3 MeV. Our calculations will further support the future and ongoing experimental campaigns for extracting astrophysical information and evaluating the two-proton removal cross-sections.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2021-03-17T09:00:05.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "breakup reactions",
      "three-body description",
      "low-lying resonances",
      "elastic breakup cross section",
      "preform three-body calculations"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 7,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}