{
  "abstract": "We investigate the prospects for improving the heavy neutral lepton (HNL) searches at the far-forward LHC experiments FASER and FASER$ν$, as well as their proposed HL-LHC successors, FASER2 and FASER$ν$2, using new HNL production mechanisms. We consider scenarios in which HNLs couple directly to a new $U(1)$ gauge boson and decay into visible Standard Model final states through mixing with active neutrinos. Focusing on the $U(1)_{B-L}$, $U(1)_{B-3L_τ}$, and $U(1)_B$ gauge extensions as benchmark models, we study HNL production through proton bremsstrahlung and Drell--Yan processes, which probe complementary mediator-mass regimes. We analyze several visible decay channels, including charged leptons, neutral mesons, and other hadrons, and evaluate the projected sensitivities for different neutrino-flavor mixing patterns. We find that these new production mechanisms that differ qualitatively from the conventional picture in which both production and decay are controlled by active-sterile mixing enable the far-forward LHC program to probe previously unexplored regions of HNL parameter space, with the first-ever demonstration of FASER$ν$ having sensitivity to HNLs and FASER2 and FASER$ν$2 offering substantially enhanced sensitivity during the HL-LHC era, even reaching the canonical seesaw prediction for all three lepton flavors. Our results demonstrate that new gauge interactions can substantially enhance HNL production independently of the active-sterile mixing that governs their visible decays, opening complementary opportunities to explore HNLs at the forward physics facilities.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.30240",
  "author_total": 6,
  "authors": [
    {
      "name": "Francis M. Burk"
    },
    {
      "name": "P. S. Bhupal Dev"
    },
    {
      "name": "Bhaskar Dutta"
    },
    {
      "name": "Tao Han"
    },
    {
      "name": "Aparajitha Karthikeyan"
    },
    {
      "name": "Doojin Kim"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/41dng012bq2rf.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.30240",
  "fulltext_url": null,
  "id": "41dng012bq2rf",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.30240",
  "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",
      "hep-ex"
    ],
    [
      "arxiv",
      "hep-ph"
    ],
    [
      "openalex",
      "3106|Particle physics theoretical and experimental studies"
    ]
  ],
  "openalex": "W7223372232",
  "pdf_url": "https://arxiv.org/pdf/2610.30240",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-21",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/41dng012bq2rf.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:34:34Z",
      "native_id": "2610.30240",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.30240"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:hep-ex",
      "subfield": "high-energy"
    }
  ],
  "title": "Probing Heavy Neutral Leptons through New Gauge Interactions at the Forward Physics Facilities",
  "title_text": "Probing Heavy Neutral Leptons through New Gauge Interactions at the Forward Physics Facilities",
  "type": "preprint",
  "updated_at": "2026-10-30T12:34:34Z",
  "url": "https://research.draconitic.com/paper/41dng012bq2rf",
  "venue": "arXiv",
  "versions": []
}