{
  "abstract": "We present a population-level spectral analysis of fast radio bursts from the second CHIME/FRB catalog using three curvature-radiation-motivated templates: point-source, one-dimensional bunch, and paired-bunch cavity models. Fits are evaluated with reduced chi-squared $χ^2_r$, AIC/BIC, and the Ljung-Box residual autocorrelation test. All three templates yield median $χ^2_r$ values close to unity for both repeating and non-repeating bursts. Repeaters show narrower $χ^2_r$ distributions than non-repeaters, with statistically significant but modest population-level differences. AIC favours the one-dimensional bunch model for the largest fraction of sources, whereas BIC increases the relative preference for the simpler point-source model. However, residual autocorrelation remains widespread across all models: only 15%-21% of sources simultaneously satisfy goodness-of-fit and residual-independence criteria, indicating persistent structured residuals beyond the tested templates. These results suggest that while curvature-radiation-motivated geometries capture the dominant spectral envelope of many FRBs, additional physical ingredients or spectral components are required to describe the fine-scale spectral structure of the data. The inferred coherence scales are $\\sim$16-18 cm for the one-dimensional model and $\\sim$25-28 cm for the cavity model.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2606.17039",
  "author_total": 3,
  "authors": [
    {
      "name": "Thonimar V. Alencar"
    },
    {
      "name": "Jéferson A. S. Fortunato"
    },
    {
      "name": "Wiliam S. Hipólito-Ricaldi"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2y3gre38scfds.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2606.17039",
  "fulltext_url": null,
  "id": "2y3gre38scfds",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2606.17039",
  "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",
      "astro-ph.HE"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2606.17039",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-29",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/2y3gre38scfds.ris",
  "sources": [
    {
      "first_seen": "2026-11-02T12:21:14Z",
      "native_id": "2606.17039",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2606.17039"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    }
  ],
  "title": "Curvature-Radiation Geometries Across the Second CHIME/FRB Fast Radio Burst Population",
  "title_text": "Curvature-Radiation Geometries Across the Second CHIME/FRB Fast Radio Burst Population",
  "type": "preprint",
  "updated_at": "2026-11-04T15:20:50Z",
  "url": "https://research.draconitic.com/paper/2y3gre38scfds",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1016/j.jheap.2026.100768",
      "pid": null,
      "relation": "published-as",
      "title": null,
      "venue": null
    }
  ]
}