{
  "abstract": "Faraday rotation provides one of the most direct probes of magnetized plasma along the line of sight, from the large-scale Galactic magnetic field to compact plasma environments local to radio sources. In particular, temporal variations in rotation measure can trace changes in the density, magnetic-field strength, or geometry of the Faraday-rotating medium, as observed in radio pulsars and fast radio bursts. Long-period radio transients (LPTs), a recently identified class of coherent radio sources with periods of hundreds to thousands of seconds, remain poorly explored because their physical nature is still uncertain. Here we present full-Stokes observations of the 421-s LPT source CHIME J0630+25 and report, for the first time, extreme rotation measure (RM) variability from approximately -400 to -1630 rad m^-2. The rapid RM changes occur on short timescales, including a difference of approximately 50 rad m^-2 between two consecutive rotation periods and a sudden change of approximately 536 rad m^-2 within approximately 2500 s. Compared with other radio-emitting sources, CHIME J0630+25 occupies an unusual region of the DM-RM plane: despite its very small DM of approximately 22 pc cm^-3, |RM| reaches over 1.6 x 10^3 rad m^-2, far exceeding that expected from the interstellar medium and pulsars. The fast and large-amplitude RM variations should arise from a compact, structured, and rapidly evolving magneto-ionic environment local to the source, possibly associated with a compact binary system.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.23259",
  "author_total": 8,
  "authors": [
    {
      "name": "Botao Li"
    },
    {
      "name": "Yongjie Jin"
    },
    {
      "name": "Shike Qu"
    },
    {
      "name": "Chaohua Gao"
    },
    {
      "name": "Wei Wang"
    },
    {
      "name": "Pei Wang"
    },
    {
      "name": "Shumei Jia"
    },
    {
      "name": "Jifeng Liu"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/668257vvp84f1.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.23259",
  "fulltext_url": null,
  "id": "668257vvp84f1",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.23259",
  "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"
    ],
    [
      "arxiv",
      "astro-ph.SR"
    ],
    [
      "openalex",
      "3103|Pulsars and Gravitational Waves Research"
    ]
  ],
  "openalex": "W7214002508",
  "pdf_url": "https://arxiv.org/pdf/2609.23259",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-20",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/668257vvp84f1.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:23:19Z",
      "native_id": "2609.23259",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.23259"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.SR",
      "subfield": "stellar"
    }
  ],
  "title": "A dynamic magneto-ionic environment around a long-period radio transient",
  "title_text": "A dynamic magneto-ionic environment around a long-period radio transient",
  "type": "preprint",
  "updated_at": "2026-10-30T12:23:19Z",
  "url": "https://research.draconitic.com/paper/668257vvp84f1",
  "venue": "arXiv",
  "versions": []
}