{
  "id": "1505.06739",
  "version": "v1",
  "published": "2015-05-25T20:00:47.000Z",
  "updated": "2015-05-25T20:00:47.000Z",
  "title": "Production of ultrahigh-energy cosmic rays via one-shot acceleration of galactic cosmic rays by jets",
  "authors": [
    "Damiano Caprioli"
  ],
  "comment": "5 pages, 2 figures, submitted to PRL - Comments welcome",
  "categories": [
    "astro-ph.HE"
  ],
  "abstract": "We propose that ultra-high-energy (UHE) cosmic rays (CRs) above $10^{18}$eV are produced in relativistic jets of powerful active galactic nuclei via an original mechanism, which we dub \"espresso\" acceleration: \"seed\" galactic CRs with energies $\\lesssim 10^{17}$eV that penetrate the jet sideways receive a \"one-shot\" boost of a factor of $\\sim\\Gamma^2$ in energy, where $\\Gamma$ is the Lorentz factor of the relativistic flow. For typical jet parameters, a few per cent of the CRs in the host galaxy can undergo this process, and powerful blazars with $\\Gamma\\gtrsim 30$ may accelerate UHECRs up to more than $10^{20}$eV. The chemical composition of espresso-accelerated UHECRs is determined by the one at the Galactic CR knee, and is expected to be proton-dominated at $10^{18}$eV and increasingly heavy at higher energies, in agreement with recent observations of the Pierre Auger Observatory.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2015-05-25T20:00:47.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "galactic cosmic rays",
      "ultrahigh-energy cosmic rays",
      "one-shot acceleration",
      "production",
      "galactic cr knee"
    ],
    "publication": {
      "doi": "10.1088/2041-8205/811/2/L38"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 5,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1373241
    }
  }
}