Photon acceleration in variable ultrarelativistic outflows and high-energy spectra of gamma-ray bursts

Andrei Gruzinov, Peter Mészáros

    Research output: Contribution to journalArticle

    Abstract

    MeV seed photons produced in shocks in a variable ultrarelativistic outflow gain energy by the Fermi mechanism, because the photons Compton scatter off relativistically colliding shells. The Fermi-modified high-energy photon spectrum has a nonuniversal slope and a universal cutoff. A significant increase in the total radiative efficiency is possible. In some gamma-ray bursts, most of the power might be emitted at the high-energy cutoff for this mechanism, which would be close to 100 MeV for outflows with a mean bulk Lorentz factor of 100.

    Original languageEnglish (US)
    JournalAstrophysical Journal
    Volume539
    Issue number1 PART 2
    StatePublished - Aug 10 2000

    Fingerprint

    gamma ray bursts
    energy spectra
    outflow
    photons
    cut-off
    energy
    seeds
    shock
    shell
    slopes
    seed

    Keywords

    • Gamma rays: bursts
    • Radiation mechanisms: nonthermal

    ASJC Scopus subject areas

    • Space and Planetary Science

    Cite this

    Photon acceleration in variable ultrarelativistic outflows and high-energy spectra of gamma-ray bursts. / Gruzinov, Andrei; Mészáros, Peter.

    In: Astrophysical Journal, Vol. 539, No. 1 PART 2, 10.08.2000.

    Research output: Contribution to journalArticle

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