{
  "abstract": "We propose to measure hard exclusive $α$-knockout reactions from the light $α$-conjugate nuclei $^{12}$C, $^{16}$O, and $^{20}$Ne using electron scattering. Three reaction channels will be measured for the first time on the same target set: (i) the quasi-elastic knockout $(e, e' α)$ knockout, which establishes a baseline against $α$-clustering model calculations and tests final-state-interaction (FSI) models; (ii) coherent deeply virtual Compton scattering (DVCS) on a bound $α$, which provides a quark-level probe of the bound system through the beam-spin asymmetry; and (iii) coherent vector-meson production ($ϕ$ and J/{$ψ$}) on a bound $α$, which probes the gluon distribution of the bound cluster through two-gluon exchange. The central observables are ratios of cross sections and beam-spin asymmetries between the bound $α$ in $^{12}$C, $^{16}$O, and $^{20}$ Ne and the free $^4$He ground state. Together these measurements directly address the question of the role of QCD in the structure of light nuclei : do the quark and gluon distributions of an $α$ embedded in a heavier nucleus differ from those of a free 4He, and do those modifications track the increasing $α$-clustering strength along the $α$-conjugate chain? The measurement will use the 12 GeV CEBAF accelerator in Hall B with the CLAS12 spectrometer instrumented with the ALERT low-energy recoil detector and high-pressure gas straw targets. ALERT, which replaced the CLAS12 silicon vertex tracker, was successfully commissioned and operated during Run Group L (RG-L) from April through August 2025. It uniquely provides identification of low-momentum recoiling light ions (p, d, t, $^3$He, and $^4$He) close to the beamline at the high luminosities required by these exclusive channels.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.16218",
  "author_total": 25,
  "authors": [
    {
      "name": "Whitney R. Armstrong"
    },
    {
      "name": "Ian Cloët"
    },
    {
      "name": "Fernando A. Flor"
    },
    {
      "name": "Sylvester Joosten"
    },
    {
      "name": "Bobae Kim"
    },
    {
      "name": "Minho Kim"
    },
    {
      "name": "Henry T. Klest"
    },
    {
      "name": "Zein-Eddine Meziani"
    },
    {
      "name": "Chao Peng"
    },
    {
      "name": "Valerii Klimenko"
    },
    {
      "name": "Noémie Pilleux"
    },
    {
      "name": "Maria Żurek"
    },
    {
      "name": "Jacob C. Dulya"
    },
    {
      "name": "Zhiwan Xu"
    },
    {
      "name": "Lamiaa El Fassi"
    },
    {
      "name": "Penn Smith"
    },
    {
      "name": "Nazmus S. Ifat"
    },
    {
      "name": "Sangbaek Lee"
    },
    {
      "name": "Suman Shrestha"
    },
    {
      "name": "Nikos Sparveris"
    },
    {
      "name": "Fatiha Benmokhtar"
    },
    {
      "name": "Christine Ploen"
    },
    {
      "name": "Raphaël Dupré"
    },
    {
      "name": "Jennifer Rittenhouse West"
    },
    {
      "name": "Stanley J. Brodsky"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/40q7j6qdb4hws.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.16218",
  "fulltext_url": null,
  "id": "40q7j6qdb4hws",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.16218",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "nucl-ex"
    ],
    [
      "openalex",
      "3106|Nuclear physics research studies"
    ]
  ],
  "openalex": "W7221771872",
  "pdf_url": "https://arxiv.org/pdf/2610.16218",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-15",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/40q7j6qdb4hws.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:29:50Z",
      "native_id": "2610.16218",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.16218"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:nucl-ex",
      "subfield": "nuclear"
    }
  ],
  "title": "Letter of Intent for Alpha Knockout from Nuclei in Hard Exclusive Processes with ALERT",
  "title_text": "Letter of Intent for Alpha Knockout from Nuclei in Hard Exclusive Processes with ALERT",
  "type": "preprint",
  "updated_at": "2026-10-30T12:29:50Z",
  "url": "https://research.draconitic.com/paper/40q7j6qdb4hws",
  "venue": "arXiv",
  "versions": []
}