{
  "id": "1910.04174",
  "version": "v1",
  "published": "2019-10-09T18:00:04.000Z",
  "updated": "2019-10-09T18:00:04.000Z",
  "title": "A Black Hole X-ray Binary at $\\sim$100 Hz: Multiwavelength Timing of MAXI J1820+070 with HiPERCAM and NICER",
  "authors": [
    "J. A. Paice",
    "P. Gandhi",
    "T. Shahbaz",
    "P. Uttley",
    "Z. Arzoumanian",
    "P. A. Charles",
    "V. S. Dhillon",
    "K. C. Gendreau",
    "S. P. Littlefair",
    "J. Malzac",
    "S. Markoff",
    "T. R. Marsh",
    "R. Misra",
    "D. M. Russell",
    "A. Veledina"
  ],
  "comment": "MNRAS Letters, In Press",
  "doi": "10.1093/mnrasl/slz148",
  "categories": [
    "astro-ph.HE"
  ],
  "abstract": "We report on simultaneous sub-second optical and X-ray timing observations of the low mass X-ray binary black hole candidate MAXI J1820+070. The bright 2018 outburst rise allowed simultaneous photometry in five optical bands ($ugriz_s$) with HiPERCAM/GTC (Optical) at frame rates over 100 Hz, together with NICER/ISS observations (X-rays). Intense (factor of two) red flaring activity in the optical is seen over a broad range of timescales down to $\\sim$10 ms. Cross-correlating the bands reveals a prominent anti-correlation on timescales of $\\sim$seconds, and a narrow sub-second correlation at a lag of $\\approx$+165 ms (optical lagging X-rays). This lag increases with optical wavelength, and is approximately constant over Fourier frequencies of $\\sim$0.3-10 Hz. These features are consistent with an origin in the inner accretion flow and jet base within $\\sim$5000 Gravitational radii. An additional $\\sim$+5 s lag feature may be ascribable to disc reprocessing. MAXI J1820+070 is the third black hole transient to display a clear $\\sim$0.1s optical lag, which may be common feature in such objects. The sub-second lag $variation$ with wavelength is novel, and may allow constraints on internal shock jet stratification models.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2019-10-09T18:00:04.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "black hole x-ray binary",
      "black hole candidate maxi",
      "binary black hole candidate",
      "x-ray binary black hole",
      "shock jet stratification models"
    ],
    "tags": [
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}