Abstract
QED cascades in a strong electromagnetic field of optical range and arbitrary configuration are considered. A general expression for short-time dependence of the key electron quantum dynamical parameter is derived, allowing one to generalize the effective threshold condition of QED cascade onset. The generalized theory is applied to self-sustained cascades in a single focused laser pulse. According to numerical simulations, if a GeV electron bunch is used as a seed, an ordinary cascade can be converted into a self-sustained one. As an application, it would be also possible to produce this way bright collimated photon beams with up to GeV photon energies.
- Received 10 May 2021
- Accepted 6 July 2021
DOI:https://doi.org/10.1103/PhysRevA.104.012221
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