{
  "abstract": "The family of KY codes is an XSPEC-compatible package of fully relativistic models for spectro-polarimetric modeling of X-ray binary systems and active galactic nuclei. Within Kerr space-time, they compute accretion disc line profiles, reflection spectra from discs illuminated by Comptonized coronal radiation, and thermal disc emission including disc-corona interaction and disc self-irradiation. Many of these models include polarimetric computations, and more advanced timing variants compute X-ray, UV and optical reverberation. The primary source of Comptonized X-rays is assumed to be in the lamp-post on-axis or slab above the disc geometry. The KY codes operate at various levels of complexity; some models use analytical approximations for local re-processing, while others rely on detailed numerical tables. For the most accurate treatment of rest-frame re-processing in partially ionized accretion disc atmospheres, the KY codes employ pre-computed spectro-polarimetric tables generated with the STOKES code. These transmission and reflection tables are also designed for standalone use in XSPEC and as inputs to higher-level models beyond KY. The chapter first introduces the STOKES tables in various variants and shows their non-relativistic usage in XSPEC models for (i) an extended source illuminating a distant geometrically thin disc, and (ii) a compact source illuminating a vertically extended equatorial obscurer (e.g., a torus or thick wind). The relativistic KY ray-tracing is then described, followed by an introduction to each KY model. Examples of fits to the IXPE data of X-ray binaries and active galactic nuclei using these models are shown. Together, these models form a comprehensive and publicly available framework for spectro-polarimetric modeling and data fitting of accretion. We provide links to their online repositories.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2608.30677",
  "author_total": 2,
  "authors": [
    {
      "name": "Jakub Podgorný"
    },
    {
      "name": "Michal Dovčiak"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/fpnzsm67tnwfq.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2608.30677",
  "fulltext_url": null,
  "id": "fpnzsm67tnwfq",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2608.30677",
  "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": "W7204879460",
  "pdf_url": "https://arxiv.org/pdf/2608.30677",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-23",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/fpnzsm67tnwfq.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:35:35Z",
      "native_id": "2608.30677",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2608.30677"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    }
  ],
  "title": "STOKES tables and KY codes",
  "title_text": "STOKES tables and KY codes",
  "type": "preprint",
  "updated_at": "2026-10-30T12:35:35Z",
  "url": "https://research.draconitic.com/paper/fpnzsm67tnwfq",
  "venue": "arXiv",
  "versions": []
}