Electromagnetic cascades and the depletion of intense fields.

ORAL

Abstract

The interaction of electrons, positrons, and photons with intense electromagnetic fields gives rise to multi-photon Compton and Breit-Wheeler processes.~It is shown that electrons and/or positrons undergo a cascade-type process involving multiple~emissions of photons. These photons can consequently convert into electron-positron pairs. As a result charged~particles quickly lose their energy developing an exponentially decaying energy distribution. Moreover the multi-photon nature of~Compton and Breit-Wheeler processes implies the absorption of a significant number of photons. As a result, the interaction of a highly charged electron bunch with an intense laser pulse can lead to a significant depletion of the laser pulse energy, thus rendering the external field approximation invalid. The relevance of these results to the proposed BELLA-i beamline at BELLA center at LBNL is discussed.

*We acknowledge support from the Office of Science of the US DOE under Contract No. DE-AC02-05CH11231.

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Authors

  • Stepan Bulanov

    • Lawrence Berkeley National Laboratory
    • Lawrence Berkeley Natl Lab

  • Daniel Seipt

    • Helmholtz-Institut Jena, Germany

  • Thomas Heinzl

    • Plymouth University, Plymouth, UK

  • Mattias Marklund

    • Chalmers University of Technology, Gothenburg, Sweden

  • Qing Ji

    • Lawrence Berkeley National Laboratory

  • Sven Steinke

    • Lawrence Berkeley National Laboratory

  • Carl Schroeder

    • Lawrence Berkeley National Laboratory

  • Eric Esarey

    • Lawrence Berkeley National Laboratory

  • Wim P. Leemans

    • Lawrence Berkeley National Laboratory