{
  "abstract": "Magnetic-field amplification and angular momentum (AM) transport critically shape the secular evolution, lifetime, and electromagnetic signatures of binary neutron-star merger remnants. While the magnetorotational instability can operate in the outer negative-shear regions of the neutron-star remnant and accretion disk, the positive-shear, stably stratified core may instead be susceptible to the Tayler-Spruit dynamo. We present the first global, long-term general-relativistic neutrino-radiation magnetohydrodynamics simulations of a neutron-star merger remnant incorporating the unresolved Tayler-Spruit dynamo through a new mean-field dynamo subgrid prescription. Our axisymmetric simulations starting from a realistic merger remnant show that the Tayler-Spruit dynamo is primarily active in high-latitude regions of the remnant core. The resulting Maxwell stresses redistribute AM on a spin-down timescale of a few hundred milliseconds, substantially flattening the core rotation profile and transferring mass and AM from the outer remnant into the disk. This produces a more massive, extended, and strongly magnetized disk with a low electron fraction, leading to substantially more neutron-rich ejecta. Our results demonstrate that currently unmodelled Tayler-Spruit dynamo action can qualitatively alter the rotational evolution, collapse prospects, disk formation, and multi-messenger signatures of long-lived neutron-star merger remnants.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2607.28556",
  "author_total": 2,
  "authors": [
    {
      "name": "Harry Ho-Yin Ng"
    },
    {
      "name": "Elias R. Most"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/23d3j9xxhh4y7.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2607.28556",
  "fulltext_url": null,
  "id": "23d3j9xxhh4y7",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2607.28556",
  "language": null,
  "licence": "CC-BY-NC-SA-4.0",
  "licence_label": "CC BY-NC-SA 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by-nc-sa/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "astro-ph.HE"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2607.28556",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-28",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/23d3j9xxhh4y7.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:25:12Z",
      "native_id": "2607.28556",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2607.28556"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    }
  ],
  "title": "Spinning down neutron-star merger remnants with the Tayler-Spruit dynamo: Global simulations reveal the formation of massive disks and neutron-rich ejecta",
  "title_text": "Spinning down neutron-star merger remnants with the Tayler-Spruit dynamo: Global simulations reveal the formation of massive disks and neutron-rich ejecta",
  "type": "preprint",
  "updated_at": "2026-10-30T12:25:12Z",
  "url": "https://research.draconitic.com/paper/23d3j9xxhh4y7",
  "venue": "arXiv",
  "versions": []
}