{
  "id": "astro-ph/0503634",
  "version": "v1",
  "published": "2005-03-29T22:20:16.000Z",
  "updated": "2005-03-29T22:20:16.000Z",
  "title": "Discovery of Optical Emission in the Hotspots of Three 3CR Quasars: High-Energy Particle Acceleration in Powerful Radio Hotspots",
  "authors": [
    "C. C. Cheung",
    "J. F. C. Wardle",
    "T. Chen"
  ],
  "comment": "ApJ accepted, 13 pages, downgraded quality figures for astro-ph",
  "journal": "Astrophys.J. 628 (2005) 104-112",
  "doi": "10.1086/430634",
  "categories": [
    "astro-ph"
  ],
  "abstract": "Archival Hubble Space Telescope WFPC2 images were used to search for optical emission associated with the radio jets of a number of luminous quasars. From this search, we report new optical hotspot detections in the well-known blazar 3C~454.3 and the lobe-dominated quasars 3C~275.1 and 3C~336. We also find optical emission in the vicinity of the hotspot in 3C~208, but believe this is a chance alignment. Optical emission from the arcsecond-scale jet in 3C~454.3 is also detected. Multi-frequency archival radio data from the VLA and MERLIN are analyzed, and the synchrotron spectra of these high-power hotspots are presented. We estimate that their break frequencies are in the range of $10^{10}-10^{11}$ Hz, with large uncertainties due to the wide gap in frequency coverage between the radio and optical bands. We also calculate their equipartition magnetic fields, and find that the anti-correlation between break frequency and magnetic field found by Brunetti et al. for lower power hotspots extends to these high power hotspots. This supports their model of hot-spots based on shock acceleration and synchrotron losses.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2005-03-29T22:20:16.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "optical emission",
      "high-energy particle acceleration",
      "powerful radio hotspots",
      "space telescope wfpc2 images",
      "3cr quasars"
    ],
    "tags": [
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 13,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 679300
    }
  }
}