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arXiv · 2506.06814

An analytical optimization of plasma density profiles for downramp injection in laser wake-field acceleration

Gaetano Fiore·Paolo Tomassini
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Abstract

We propose and detail a multi-step analytical procedure, based on an improved fully relativistic plane model for Laser Wake Field Acceleration, to tailor the initial density of a cold diluted plasma to the laser pulse profile, so as to control and optimize the partial wave-breaking of the plasma wave and maximize the acceleration of small bunches of electrons self-injected by the first wave-breaking at the density down-ramp, at least in the first stages of their acceleration phase. We find an excellent agreement with the results of Particle In Cell simulations obtained with the same input data.

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Gaetano Fiore, Paolo Tomassini. 2025-06-07. An analytical optimization of plasma density profiles for downramp injection in laser wake-field acceleration. https://doi.org/10.1016/j.physd.2026.135124

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