{
  "abstract": "The engulfment of a neutron star (NS) by a massive companion initiates a highly dynamic common-envelope (CE) evolution phase. As the NS spirals into the dense stellar core, it is subjected to hypercritical accretion rates that threaten to rapidly collapse the NS into a black hole (BH). However, if the infalling envelope possesses sufficient angular momentum and magnetic fields, the NS might survive longer and launch feedback-driving jets. To investigate this, we perform fully coupled, axisymmetric General Relativistic Magnetohydrodynamic (GRMHD) simulations of hyperaccreting NSs, featuring energy-integrated two-moment neutrino transport and a 13-isotope nuclear reaction network. We systematically vary the envelope rotation profile and the magnetic field strength of the NS surface ($B_{\\rm surf} \\sim 5 \\times 10^{10} - 5 \\times 10^{13}$~G). In non-magnetised models, we find that envelope rotation naturally forms a centrifugal barrier and a geometrically thick accretion disk, which suppresses the mass accretion rate and lowers the neutrino luminosity; conversely, the intrinsic spin of the NS has a negligible global impact. In magnetised models, the differential rotation of the accretion flow vigorously amplifies the toroidal magnetic field via the $Ω$-effect, driving the expansion of magnetic towers. Crucially, for strong initial surface magnetic fields ($B_{\\rm surf} \\gtrsim 2.3 \\times 10^{13}$~G), the intense magnetic pressure could completely halt the accretion flow at the NS surface and evacuates a low-density polar funnel. We conclude that while this highly magnetised NS engine successfully delays prompt BH formation and may launch low-power precursor jets (with powers up to ${\\sim} 10^{46}~{\\rm erg/s}$) capable of generating observable X-ray flares, it lacks the energy budget to unbind the massive envelope, potentially setting the stage for a subsequent BH-driven explosion.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2608.09395",
  "author_total": 3,
  "authors": [
    {
      "name": "Patrick Chi-Kit Cheong"
    },
    {
      "name": "Christopher L. Fryer"
    },
    {
      "name": "David Radice"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/0dpaxzb1yhrmf.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2608.09395",
  "fulltext_url": null,
  "id": "0dpaxzb1yhrmf",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2608.09395",
  "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|Astrophysical Phenomena and Observations"
    ]
  ],
  "openalex": "W7202207574",
  "pdf_url": "https://arxiv.org/pdf/2608.09395",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-13",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/0dpaxzb1yhrmf.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:29:31Z",
      "native_id": "2608.09395",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2608.09395"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    }
  ],
  "title": "Hyperaccreting Magnetised Neutron Stars inside Rotating Massive Envelopes: Low-Power Jets and Precursor Flares",
  "title_text": "Hyperaccreting Magnetised Neutron Stars inside Rotating Massive Envelopes: Low-Power Jets and Precursor Flares",
  "type": "preprint",
  "updated_at": "2026-10-30T12:29:31Z",
  "url": "https://research.draconitic.com/paper/0dpaxzb1yhrmf",
  "venue": "arXiv",
  "versions": []
}