{
  "id": "1103.5746",
  "version": "v4",
  "published": "2011-03-29T20:00:02.000Z",
  "updated": "2011-09-14T13:20:10.000Z",
  "title": "Gamma-Ray Burst without Baryonic and Magnetic Load?",
  "authors": [
    "Kunihito Ioka",
    "Yutaka Ohira",
    "Norita Kawanaka",
    "Akira Mizuta"
  ],
  "comment": "10 pages, 3 figures, final version to be published in Progress of Theoretical Physics",
  "journal": "Prog. Theor. Phys. 126 (2011), 555-564",
  "doi": "10.1143/PTP.126.555",
  "categories": [
    "astro-ph.HE"
  ],
  "abstract": "We show that, contrary to common belief, internal shocks can arise in an accelerating radiation-dominated jet if it is confined even weakly to a converging opening angle because the acceleration declines. The radiation-dominated internal shock (RDIS) enables a very efficient yet highly nonthermal emission by Fermi-like photon acceleration, keeping the electron-positron ($e^{\\pm}$) pair photosphere and inertia up to a high Lorentz factor >1000. In gamma-ray bursts (GRBs), a weak confinement would persist beyond the progenitor star or surrounding matter because of the fast cocoon accompanying the breakout jet. The simplest model predicts few high-energy cosmic rays and neutrinos, and a correlation between the early afterglow and the GeV-TeV prompt emission. The central engine allows a less fine-tuned baryon load than previously thought, even including pure-leptonic unmagnetized outflows.",
  "revisions": [
    {
      "version": "v4",
      "updated": "2011-09-14T13:20:10.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "gamma-ray burst",
      "magnetic load",
      "internal shock",
      "high lorentz factor",
      "simplest model predicts"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "journal": "Progress of Theoretical Physics",
      "year": 2011,
      "month": "Sep",
      "volume": 126,
      "number": 3,
      "pages": 555
    },
    "note": {
      "typesetting": "TeX",
      "pages": 10,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 894533,
      "adsabs": "2011PThPh.126..555I"
    }
  }
}