{
  "abstract": "Axion-star mass-radius relations are commonly computed using different orders of relativistic approximation, making it important to determine where these descriptions remain reliable. We perform a unified numerical comparison of axion-star ground-state configurations in the Newtonian Schrödinger-Poisson description, first- and second-order relativistic effective field theories, and the full Einstein-Klein-Gordon system for a real scalar field. Using the same attractive quartic self-interaction in all four descriptions, we scan $|\\widetildeλ|=(M_{\\rm Pl}/f_a)^2$ and determine the maximum masses and corresponding enclosed-mass radii. All descriptions recover the common large-$|\\widetildeλ|$ dilute-star scaling, while substantial differences appear at weak and moderate coupling. The relativistic EFTs interpolate systematically between the Newtonian and full-GR results. For part of the maximum-mass sequence where $\\max|ϕ|/f_a=O(1)$, we test the temporal-harmonic and potential truncations explicitly in full GR. The higher-harmonic expansion shows rapid convergence, while restoring the complete single-cosine potential changes the maximum mass only at the percent level and $R_{95}$ at the several-percent level. Together with the systematic convergence of the relativistic EFT descriptions toward full GR, these results show that the large weak-coupling departure from the Schrödinger-Poisson prediction reflects the breakdown of the nonrelativistic structural description. Our results provide a systematic benchmark for determining when Newtonian, relativistically corrected, or fully general-relativistic descriptions are required for axion-star structure. The numerical implementation used in this work is available in the Axion Star Solvers repository at https://github.com/Parisa-Arabameri/AxionStar.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.13638",
  "author_total": 4,
  "authors": [
    {
      "name": "Parisa Arabameri"
    },
    {
      "name": "Paola Arias"
    },
    {
      "name": "Francisco Colipí-Marchant"
    },
    {
      "name": "Enrico D. Schiappacasse"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/5g01z5nvevf1d.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.13638",
  "fulltext_url": null,
  "id": "5g01z5nvevf1d",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.13638",
  "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.CO"
    ],
    [
      "arxiv",
      "astro-ph.GA"
    ],
    [
      "arxiv",
      "gr-qc"
    ],
    [
      "arxiv",
      "hep-ph"
    ],
    [
      "arxiv",
      "hep-th"
    ],
    [
      "openalex",
      "3106|Dark Matter and Cosmic Phenomena"
    ]
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  "openalex": "W7213313454",
  "pdf_url": "https://arxiv.org/pdf/2609.13638",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-12",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/5g01z5nvevf1d.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:21:25Z",
      "native_id": "2609.13638",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.13638"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.CO",
      "subfield": "cosmology"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    },
    {
      "field": "physics",
      "origin": "arxiv:gr-qc",
      "subfield": "gravitation"
    },
    {
      "field": "physics",
      "origin": "arxiv:hep-ph",
      "subfield": "high-energy"
    }
  ],
  "title": "A Unified Numerical Study of Axion Stars: From the Nonrelativistic Regime to General Relativity",
  "title_text": "A Unified Numerical Study of Axion Stars: From the Nonrelativistic Regime to General Relativity",
  "type": "preprint",
  "updated_at": "2026-10-30T12:21:25Z",
  "url": "https://research.draconitic.com/paper/5g01z5nvevf1d",
  "venue": "arXiv",
  "versions": []
}