{
  "abstract": "Torque balance between gravitational radiation reaction and magnetocentrifugal accretion is one reason why accreting neutron stars rotate slower than centrifugal break-up. Random processes in the accretion disk, such as Rayleigh-Taylor instabilities and flicker noise, drive the spin frequency $f_\\ast$ and gravitational wave frequency $f_{\\rm gw}\\propto f_\\ast$ to wander stochastically around their torque balance values. Here it is shown theoretically, in terms of an idealized Ornstein-Uhlenbeck model, that the standard deviation of $f_{\\rm gw}$ is given by $σ_{f_{\\rm gw}}(h_0) \\propto f_{\\rm gw} h_0 D βT^{1/2}$, or equivalently $σ_{f_{\\rm gw}}(F_{\\rm X}) \\propto f_{\\rm gw}^{1/2} F_{\\rm X}^{1/2} D βT^{1/2}$, where $h_0$ is the characteristic wave strain, $F_{\\rm X}$ is the X-ray flux, $D$ is the source distance, and $β$ and $T$ are the fractional amplitude and autocorrelation time-scale of the stochastic torque. One can use $σ_{f_{\\rm gw}}(h_0)$ and $σ_{f_{\\rm gw}}(F_{\\rm X})$ to check the physical consistency of a detection candidate in a gravitational wave search by comparing with $σ_{f_{\\rm gw}}$ observed. Spin wandering impacts search design, because it sets the maximum time interval $\\max(T_{\\rm coh})$, during which the signal may be treated as coherent. The Ornstein-Uhlenbeck calculation predicts $10^{-1} \\lesssim \\max(T_{\\rm coh}) / (1\\, {\\rm day}) \\lesssim 10^3$, with $3\\times 10^{-2} \\lesssim βT^{1/2} / (1 \\, {\\rm s^{1/2}} ) \\lesssim 4$, for Rayleigh-Taylor instabilities and flicker noise. The predicted $\\max(T_{\\rm coh})$ is shorter typically than the year-long observation runs of audio-band interferometers operating today, emphasizing the utility of semi-coherent search algorithms, which divide the data into multiple coherent segments of duration $\\max(T_{\\rm coh})$.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.32164",
  "author_total": 1,
  "authors": [
    {
      "name": "Andrew Melatos"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/0x2czdzgbvbmv.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.32164",
  "fulltext_url": null,
  "id": "0x2czdzgbvbmv",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.32164",
  "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",
      "gr-qc"
    ],
    [
      "openalex",
      "3103|Pulsars and Gravitational Waves Research"
    ]
  ],
  "openalex": "W7214701448",
  "pdf_url": "https://arxiv.org/pdf/2609.32164",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-26",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/0x2czdzgbvbmv.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:25:12Z",
      "native_id": "2609.32164",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.32164"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    },
    {
      "field": "physics",
      "origin": "arxiv:gr-qc",
      "subfield": "gravitation"
    }
  ],
  "title": "Spin wandering of an accreting neutron star near torque balance: implications for gravitational wave searches",
  "title_text": "Spin wandering of an accreting neutron star near torque balance: implications for gravitational wave searches",
  "type": "preprint",
  "updated_at": "2026-10-30T12:25:12Z",
  "url": "https://research.draconitic.com/paper/0x2czdzgbvbmv",
  "venue": "arXiv",
  "versions": []
}