{
  "abstract": "Top-quark pair production at the LHC provides a bipartite spin system whose correlations are imprinted in the angular distributions of the decay products and can be studied with quantum-information tools. We investigate whether this spin structure can be used to probe invisible new physics in $pp\\to t\\bar t+X$, where $X$ is a spin-0 or spin-1 mediator motivated by top-philic simplified dark-matter models. Focusing on the dileptonic channel at the High-Luminosity LHC, we compare the sensitivity of the inclusive event yield, the visible invariant-mass distribution, an event-level estimator of the entanglement marker $D$, and the fiducial spin correlation $\\mathcal{D}$ measured as a function of the visible invariant mass. We find that observables retaining spin information improve the expected exclusion sensitivity with respect to rate and kinematic information alone, with $\\mathcal{D}(M_{t\\bar t}^{\\rm vis})$ providing the strongest reach for both mediator spins. The same observables also enhance the discrimination between scalar and pseudoscalar couplings of the spin-zero mediator, with $\\mathcal{D}(M_{t\\bar t}^{\\rm vis})$ again providing the strongest sensitivity, particularly at larger mediator masses. These results show that quantum-information-motivated observables of the $t\\bar t$ system can be efficient tools to probe both the presence of invisible new physics and the structure of its couplings to top quarks.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.31425",
  "author_total": 4,
  "authors": [
    {
      "name": "Blanca Belmonte"
    },
    {
      "name": "Diego Blas"
    },
    {
      "name": "Alba Cervera-Lierta"
    },
    {
      "name": "Francesco Montagno"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/8gayqe04ec6s6.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.31425",
  "fulltext_url": null,
  "id": "8gayqe04ec6s6",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.31425",
  "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": "W7214681308",
  "pdf_url": "https://arxiv.org/pdf/2609.31425",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-07",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/8gayqe04ec6s6.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:27:37Z",
      "native_id": "2609.31425",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.31425"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:hep-ex",
      "subfield": "high-energy"
    }
  ],
  "title": "Quantum probes of invisible particles in top-quark pair production at the LHC",
  "title_text": "Quantum probes of invisible particles in top-quark pair production at the LHC",
  "type": "preprint",
  "updated_at": "2026-10-30T12:27:37Z",
  "url": "https://research.draconitic.com/paper/8gayqe04ec6s6",
  "venue": "arXiv",
  "versions": []
}