{
  "abstract": "Ideal-GRMHD calculations provide the bulk accretion flows used in black-hole emission models. A localized dissipation prescription can add a resolved map of current-sheet activity while retaining that dynamical reference. We implement such a prescription in Athena++, using a smooth threshold on the dimensionless current proxy $α_J$ to select the magnetic-diffusion coefficient. The constrained-transport update is coupled to a conservative energy-flux correction. Gas heating follows from primitive recovery; $q_{Ohm}=ηJ^2$ is recorded as a diagnostic, without a second energy source. Static Fourier and traveling Alfvén tests measure the evolved thermal gain, and an open-boundary Schwarzschild test closes the Killing-energy ledger. The relative total-energy residual is below $2\\times10^{-15}$ in these tests. A two-resolution Harris matrix gives localized rate exponents $0.510\\pm0.027$ and $0.488\\pm0.028$, consistent with $1/2$ over the specified early interval. The $η=10^{-3}$ rate exceeds the same-resolution ideal control by a factor of 5.96. In matched axisymmetric M87*-like runs, localized diffusion changes the early mean magnetic flux, accretion rate, and normalized flux by less than $0.02\\%$, with a radial-density distance of $0.005\\%$. During the late active phase, a common-restart on/off comparison keeps these mean shifts below $1.6\\%$, within the intrinsic temporal variability, and gives a density distance of $0.29\\%$. Uniform diffusion at the tested coefficient reduces the raw flux and accretion rate by $85\\%$ and $99.8\\%$. These comparisons establish a spatially selective diffusion prescription with explicit energy accounting and a quantified, small bulk-flow response.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.12377",
  "author_total": 2,
  "authors": [
    {
      "name": "Songyan Dai"
    },
    {
      "name": "Renyue Cen"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/1vqfefg3pz5t7.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.12377",
  "fulltext_url": null,
  "id": "1vqfefg3pz5t7",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.12377",
  "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.GA"
    ],
    [
      "arxiv",
      "astro-ph.HE"
    ],
    [
      "openalex",
      "3103|Astrophysical Phenomena and Observations"
    ]
  ],
  "openalex": "W7213116403",
  "pdf_url": "https://arxiv.org/pdf/2609.12377",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-11",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/1vqfefg3pz5t7.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:21:07Z",
      "native_id": "2609.12377",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.12377"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    }
  ],
  "title": "A Localized Current-Sheet Magnetic-Diffusion and Heating Prescription for Ideal-GRMHD Simulations of M87*-like Accretion Flows",
  "title_text": "A Localized Current-Sheet Magnetic-Diffusion and Heating Prescription for Ideal-GRMHD Simulations of M87*-like Accretion Flows",
  "type": "preprint",
  "updated_at": "2026-10-30T12:21:07Z",
  "url": "https://research.draconitic.com/paper/1vqfefg3pz5t7",
  "venue": "arXiv",
  "versions": []
}