{
  "abstract": "Background: The deformed halo nucleus $^{31}$Ne exhibits unique structural properties arising from the interplay between its halo neutron and the deformation of the $^{30}$Ne core. While previous studies have established the nature of its weakly-bound ground state through reaction cross sections and inclusive breakup measurements, the structure of its excited states in the low-energy continuum, which are expected to appear as resonances, remains largely unexplored. Purpose: We investigate the structure of these resonant states and clarify their rotational nature and formation mechanism. Method: The structure of $^{31}$Ne is described using the particle rotor model (PRM), which explicitly treats the coupling between core excitation and single-particle motion in both bound and continuum states. Results: The calculations predict the emergence of unbound rotational states in the low-energy continuum of $^{31}$Ne, which form a rotational sequence built on the weakly-bound Nilsson [321 3/2] configuration. As the total angular momentum increases along the rotational band, the intrinsic Nilsson structure is largely preserved, whereas the dominant core-spin component shifts to higher spins. These resonances are stabilized through the combined effects of coupling to higher-lying closed core-excited channels and reduced effective neutron relative energies, and can therefore be interpreted as rotational Feshbach resonances. Conclusion: The present study elucidates the formation mechanism of rotational Feshbach resonances in $^{31}$Ne. This mechanism is expected to be a general feature of weakly-bound deformed nuclei. Exclusive breakup measurements with coincident detection of $γ$ rays from the de-exciting core will provide crucial tests of the proposed formation mechanism of rotational Feshbach resonances.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.04758",
  "author_total": 4,
  "authors": [
    {
      "name": "Shin Watanabe"
    },
    {
      "name": "Shoya Ogawa"
    },
    {
      "name": "Takuma Matsumoto"
    },
    {
      "name": "Kazuyuki Ogata"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/e5zd6yqazffph.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.04758",
  "fulltext_url": null,
  "id": "e5zd6yqazffph",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.04758",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "nucl-th"
    ],
    [
      "openalex",
      "3106|Nuclear physics research studies"
    ]
  ],
  "openalex": "W7211881718",
  "pdf_url": "https://arxiv.org/pdf/2609.04758",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-04",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/e5zd6yqazffph.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:14Z",
      "native_id": "2609.04758",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.04758"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:nucl-th",
      "subfield": "nuclear"
    }
  ],
  "title": "Rotational Feshbach resonances in the deformed halo nucleus $^{31}$Ne",
  "title_text": "Rotational Feshbach resonances in the deformed halo nucleus ^31Ne",
  "type": "preprint",
  "updated_at": "2026-10-30T12:19:14Z",
  "url": "https://research.draconitic.com/paper/e5zd6yqazffph",
  "venue": "arXiv",
  "versions": []
}