{
  "id": "2003.01911",
  "version": "v1",
  "published": "2020-03-04T06:34:06.000Z",
  "updated": "2020-03-04T06:34:06.000Z",
  "title": "Quasi-periodic Oscillation and Evidence of a Curved Jet in the Blazar 3C 454.3",
  "authors": [
    "Arkadipta Sarkar",
    "Alok C. Gupta",
    "Varsha R. Chitnis",
    "Paul J. Wiita"
  ],
  "comment": "10 pages, 5 figures; Submitted to ApJL",
  "categories": [
    "astro-ph.HE"
  ],
  "abstract": "We report the detection of a quasi-periodic oscillation (QPO) in light curves of the blazar 3C 454.3. Periodic flux modulation was detected simultaneously in both $\\gamma$--ray and optical wavebands with a dominant period of $\\sim 47$ days. This period has a significance of over $4.2\\sigma$ in the \\textit{Fermi} $\\gamma$--ray waveband and around $2.4\\sigma$ in the optical V band. This QPO lasted for over 450 days (from MJD 56800 to 57250) resulting in over nine observed periods which is among the highest number of periods ever detected in a blazar light curve. The lower significance of the dominant period in optical wavebands is attributed to the absence of optical data for a number of QPO cycles due to the daytime transit of the source. We explore several physical models to explain the origin of this transient quasi-periodic modulation in the observed flux with a month-like period. These scenarios include a binary black hole system, a hotspot orbiting close to the innermost stable circular orbit of the supermassive black hole, and precessing jets. We conclude that the most likely scenario involves a region of enhanced emission moving helically inside a jet. Also, a curvature of $\\sim 0.05^{\\circ}$ pc$^{-1}$ in the jet fits the emission much better than does a straight blazar jet.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2020-03-04T06:34:06.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "blazar 3c",
      "quasi-periodic oscillation",
      "curved jet",
      "emission moving helically inside",
      "dominant period"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 10,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}