{
  "abstract": "We present an analysis of a long NuSTAR observation of the intermediate supergiant fast X-ray transient (SFXT) IGR J00370+6122, obtained around the peak of its orbital modulation. The observation has a net exposure ~93 ks. During the observation, the source displayed a bright flaring event that was resolved into numerous short flares with durations of 10-1000 s. The 3-70 keV luminosity spanned a dynamic range of ~200, from ~1E34 to ~1.8E36 erg/s; the maximum was reached for only ~40 s in total. The spectrum is well described by an absorbed double-Comptonisation model, with parameters consistent with those found in other X-ray pulsars accreting at similarly low luminosities. This is the first detection of a double-hump continuum in IGR J00370+6122, which extends this spectral state to the class of intermediate SFXTs. We searched for the previously reported ~346 s and ~674 s periodicities and find no significant signal at either period, which makes their interpretation as the neutron star spin period less likely. Using ~21 yr of Swift/BAT monitoring, we refine the orbital period of the system to P_orb=15.6654 +/- 0.0008 d. Finally, we discuss the observed flaring activity in the framework of quasi-spherical settling accretion, which is expected at the observed luminosities.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.27925",
  "author_total": 6,
  "authors": [
    {
      "name": "L. Ducci"
    },
    {
      "name": "M. M. Serim"
    },
    {
      "name": "P. Romano"
    },
    {
      "name": "E. Bozzo"
    },
    {
      "name": "L. Ji"
    },
    {
      "name": "C. Malacaria"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/36ft7a11cd8jq.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.27925",
  "fulltext_url": null,
  "id": "36ft7a11cd8jq",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.27925",
  "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.HE"
    ],
    [
      "openalex",
      "3103|Astrophysical Phenomena and Observations"
    ]
  ],
  "openalex": "W7223099816",
  "pdf_url": "https://arxiv.org/pdf/2610.27925",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-20",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/36ft7a11cd8jq.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:34:04Z",
      "native_id": "2610.27925",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.27925"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    }
  ],
  "title": "A bright X-ray flaring event from the intermediate supergiant fast X-ray transient IGR J00370+6122 observed with NuSTAR",
  "title_text": "A bright X-ray flaring event from the intermediate supergiant fast X-ray transient IGR J00370+6122 observed with NuSTAR",
  "type": "preprint",
  "updated_at": "2026-10-30T12:34:04Z",
  "url": "https://research.draconitic.com/paper/36ft7a11cd8jq",
  "venue": "arXiv",
  "versions": []
}