{
  "id": "2407.07091",
  "version": "v1",
  "published": "2024-07-09T17:59:35.000Z",
  "updated": "2024-07-09T17:59:35.000Z",
  "title": "General Relativistic effects and the NIR variability of Sgr A* II: A systematic approach to temporal asymmetry",
  "authors": [
    "Sebastiano D. von Fellenberg",
    "Gunther Witzel",
    "Michi Bauboeck",
    "Hui-Hsuan Chung",
    "Nicola Marchili",
    "Greg Martinez",
    "Matteo Sadun-Bordoni",
    "Guillaume Bourdarot",
    "Tuan Do",
    "Antonia Drescher",
    "Giovanni Fazio",
    "Frank Eisenhauer",
    "Reinhard Genzel",
    "Stefan Gillessen",
    "Joseph L. Hora",
    "Felix Mang",
    "Thomas Ott",
    "Howard A. Smith",
    "Eduardo Ros",
    "Diogo C. Ribeiro",
    "Felix Widmann",
    "S. P. Willner",
    "J. Anton Zensus"
  ],
  "comment": "Accepted for publication in A&A letters",
  "categories": [
    "astro-ph.HE",
    "astro-ph.GA"
  ],
  "abstract": "A systematic study, based on the third-moment structure function, of Sgr A*'s variability finds an exponential rise time $\\tau_{1,\\rm{obs}}=14.8^{+0.4}_{-1.5}~\\mathrm{minutes}$ and decay time $\\tau_{2,\\rm{obs}}=13.1^{+1.3}_{-1.4}~\\mathrm{minutes}$. This symmetry of the flux-density variability is consistent with earlier work, and we interpret it as caused by the dominance of Doppler boosting, as opposed to gravitational lensing, in Sgr~A*'s light curve. A relativistic, semi-physical model of Sgr~A* confirms an inclination angle $i<45$ degrees. The model also shows that the emission of the intrinsic radiative process can have some asymmetry even though the observed emission does not. The third-moment structure function, which is a measure of the skewness of the light-curve increments, may be a useful summary statistic in other contexts of astronomy because it senses only temporal asymmetry, i.e., it averages to zero for any temporally symmetric signal.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2024-07-09T17:59:35.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "general relativistic effects",
      "temporal asymmetry",
      "systematic approach",
      "nir variability",
      "third-moment structure function"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}