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تسجيل مستخدم جديدThe Effect of Laser Focusing Conditions on Propagation and Monoenergetic Electron Production in Laser Wakefield Accelerators
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The effect of laser focusing conditions on the evolution of relativistic plasma waves in laser wakefield accelerators is studied both experimentally and with particle-in-cell simulations. For short focal length ($w_0 < lambda_p$) interactions, beam break-up prevents stable propagation of the pulse. High field gradients lead to non-localized phase injection of electrons, and thus broad energy spread beams. However for long focal length geometries ($w_0 > lambda_p$), a single optical filament can capture the majority of the laser energy, and self-guide over distances comparable to the dephasing length, even for these short-pulses ($ctau approx lambda_p$). This allows the wakefield to evolve to the correct shape for the production of the monoenergetic electron bunches, as measured in the experiment.
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