{
  "abstract": "We perform a theoretical study of intermediate-energy quasifree one-proton knockout reactions on proton targets. Single-particle wave functions constrained by the experimental proton separation energies are employed to calculate longitudinal momentum distributions, one-proton removal cross sections, and full momentum-space profiles for $^{26}$P, $^{27}$S and $^{31}$Ar nuclei. To establish robust criteria to identify proton halos, the analysis is extended beyond the traditional momentum-width approach by investigating the spatial extension of the valence proton through root-mean-square radii and the probability that the proton resides outside the core nucleus, $P(r>R_{\\rm core})$. We also examine Coulomb-barrier systematics, mirror-nucleus comparisons, realistic spectroscopic mixtures, finite experimental momentum resolution, and uncertainties associated with the proton separation energy. Our calculations indicate that proton-halo structure cannot be identified reliably from a single observable. A consistent interpretation emerges only when momentum distributions, spatial observables, Coulomb effects, and many-body structure are considered simultaneously. Within the present model, $^{26}$P exhibits the strongest proton-halo signatures, while $^{27}$S retains pronounced halo-like features despite its larger Coulomb barrier. The more strongly confined $^{31}$Ar provides a useful comparison and illustrates the progressive suppression of halo observables with increasing binding and core charge.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2608.06524",
  "author_total": 3,
  "authors": [
    {
      "name": "Taslima S. C. Diba"
    },
    {
      "name": "Carlos A. Bertulani"
    },
    {
      "name": "Ronaldo V. Lobato"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/32nhbygjhdan9.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2608.06524",
  "fulltext_url": null,
  "id": "32nhbygjhdan9",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2608.06524",
  "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-ex"
    ],
    [
      "arxiv",
      "nucl-th"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2608.06524",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-06",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/32nhbygjhdan9.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:27:22Z",
      "native_id": "2608.06524",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2608.06524"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:nucl-ex",
      "subfield": "nuclear"
    }
  ],
  "title": "Momentum Distributions and Spatial Signatures of Proton Halos in the sd Shell",
  "title_text": "Momentum Distributions and Spatial Signatures of Proton Halos in the sd Shell",
  "type": "preprint",
  "updated_at": "2026-10-30T12:27:22Z",
  "url": "https://research.draconitic.com/paper/32nhbygjhdan9",
  "venue": "arXiv",
  "versions": []
}