{
  "abstract": "The April 2018 gamma-ray flare of the flat-spectrum radio quasar 3C~279 exhibited sharp peaks within a broader outburst. Its rapid substructure was previously attributed to magnetic reconnection. Motivated by its distinctive temporal profile within our comparison sample of bright blazar flares and its resemblance to caustic-crossing features in optical microlensing events, we investigate a finite-source binary-microlensing interpretation. A jointly fitted model of binary-lens magnification, a smooth intrinsic flare, and Gaussian-process variability reproduces the principal double-peaked structure of the GeV light curve. The adopted local solution has a binary mass ratio of $q\\simeq0.098$ and an Einstein timescale of $t_{\\rm E}\\simeq0.327$~d. The absolute lens mass and projected source radius depend on the lens distance and relative proper motion. The fitted geometry can correspond to a Galactic planetary-mass binary or an intervening stellar or substellar system, with different physical source sizes in each case. We present binary microlensing as a testable interpretation of this event, with the finite-source structure offering a potential probe of the compact GeV-emitting region.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.40255",
  "author_total": 11,
  "authors": [
    {
      "name": "Yihong Yang"
    },
    {
      "name": "Jianeng Zhou"
    },
    {
      "name": "Haibin Ren"
    },
    {
      "name": "Wei Zhu"
    },
    {
      "name": "Haiyun Zhang"
    },
    {
      "name": "Dahai Yan"
    },
    {
      "name": "Hongping Deng"
    },
    {
      "name": "Hengxiao Guo"
    },
    {
      "name": "Zhen Yan"
    },
    {
      "name": "Liang Chen"
    },
    {
      "name": "Minfeng Gu"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2nsvm9wer4tke.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.40255",
  "fulltext_url": null,
  "id": "2nsvm9wer4tke",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.40255",
  "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": null,
  "pdf_url": "https://arxiv.org/pdf/2610.40255",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-29",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/2nsvm9wer4tke.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:36:28Z",
      "native_id": "2610.40255",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.40255"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    }
  ],
  "title": "A Candidate Binary Microlensing Event in the 2018 Gamma-Ray Flare of 3C 279",
  "title_text": "A Candidate Binary Microlensing Event in the 2018 Gamma-Ray Flare of 3C 279",
  "type": "preprint",
  "updated_at": "2026-11-01T12:20:47Z",
  "url": "https://research.draconitic.com/paper/2nsvm9wer4tke",
  "venue": "arXiv",
  "versions": []
}