Signatures of quantum effects on radiation reaction in laser-electron-beam collisions
Abstract
Two signatures of quantum effects on radiation reaction in the collision of a ∼ GeV electron beam with a high intensity (>3× 1020 W cm-2) laser pulse have been considered. We show that the decrease in the average energy of the electron beam may be used to measure the Gaunt factor g for synchrotron emission. We derive an equation for the evolution of the variance in the energy of the electron beam in the quantum regime, i.e. quantum efficiency parameter η \not ≪ 1. We show that the evolution of the variance may be used as a direct measure of the quantum stochasticity of the radiation reaction and determine the parameter regime where this is observable. For example, stochastic emission results in a 25% increase in the standard deviation of the energy spectrum of a GeV electron beam, 1 fs after it collides with a laser pulse of intensity 1021 W cm-2. This effect should therefore be measurable using current high-intensity laser systems.
- Publication:
-
Journal of Plasma Physics
- Pub Date:
- October 2017
- DOI:
- 10.1017/S0022377817000642
- arXiv:
- arXiv:1708.04511
- Bibcode:
- 2017JPlPh..83e7102R
- Keywords:
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- intense particle beams;
- plasma dynamics;
- plasma simulation;
- Physics - Plasma Physics
- E-Print:
- Journal of Plasma Physics, 83, 715830502 (2017)