{
  "abstract": "We provide transition probabilities and Maxwellian-averaged collision-strengths for the electron-impact excitation of Ce {\\sc ii} - {\\sc iv}. These ions are potentially abundant in kilonovae (KNe) and feature both forbidden and allowed transitions in the infrared. These atomic data are obtained using the {\\sc grasp}$^0$ atomic structure code, interfaced with the non-perturbative {\\sc darc} R-matrix close-coupling codes. We additionally use {\\sc autostructure} to produce dielectronic and radiative recombination rate coefficients for Ce {\\sc ii} - {\\sc vi}. Using this data, we calculate an approximate ionization balance including non-thermal ionization rates with deposition rates from realistic models. We find Ce {\\sc ii} - {\\sc iv} to be of roughly equal abundance, subject to ejecta conditions. We find that generally we need $\\gtrsim$ 10$^{-3}$ M$_{\\odot}$ of Ce in total to produce emission of comparable luminosity to the features in the spectrum of AT2023vfi. In particular, it is found that [Ce {\\sc iv}] 4.5 $μ$m requires both strong ionization and weak recombination, as well as a production of Ce considerably stronger than that of the solar abundance in order to have luminosity comparable to the apparent emission in this wavelength vicinity in \\grb. %which is seemingly incompatible with the current understanding of the bulk composition of KNe. With such strict requirements on individual element masses, the detection of individual lanthanides on a line-by-line basis in the nebular phase seems unlikely - but lanthanides may remain important for cooling and early time analyses.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.15900",
  "author_total": 6,
  "authors": [
    {
      "name": "Leo Patrick Mulholland"
    },
    {
      "name": "Niamh Ferguson"
    },
    {
      "name": "Luke J. Shingles"
    },
    {
      "name": "Catherine A. Ramsbottom"
    },
    {
      "name": "Connor P. Ballance"
    },
    {
      "name": "Stuart A. Sim"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/1k3bqk1j52hfc.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.15900",
  "fulltext_url": null,
  "id": "1k3bqk1j52hfc",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.15900",
  "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",
      "astro-ph.HE"
    ],
    [
      "openalex",
      "3103|Gamma-ray bursts and supernovae"
    ]
  ],
  "openalex": "W7213297335",
  "pdf_url": "https://arxiv.org/pdf/2609.15900",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-14",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/1k3bqk1j52hfc.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:21:25Z",
      "native_id": "2609.15900",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.15900"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    }
  ],
  "title": "Ce II-IV emission in kilonovae with R-matrix collision strengths and distorted wave recombination rates",
  "title_text": "Ce II-IV emission in kilonovae with R-matrix collision strengths and distorted wave recombination rates",
  "type": "preprint",
  "updated_at": "2026-10-30T12:21:25Z",
  "url": "https://research.draconitic.com/paper/1k3bqk1j52hfc",
  "venue": "arXiv",
  "versions": []
}