Lorenzo MARTELLI, UPX group, LOA: Average Current Enhancement of Laser-Plasma Accelerators

Laser-plasma accelerators have demonstrated remarkable capabilities in generating high-energy electron beams exceeding 1 GeV, driven by hundreds-TW laser systems. However, many practical applications necessitate higher average beam currents rather than elevated energies. Moreover, in fields like industrial X-ray tomography, there’s a pressing need to control maximum energy outputs due to radiation safety considerations. In this seminar, we delve into an underexplored acceleration regime aimed at enhancing average beam currents at a few MeV. Utilizing Particle-in-Cell (PIC) simulations, we provide a detailed analysis of the acceleration processes, highlighting Ponderomotive Acceleration (PA) and Direct Laser Acceleration (DLA) as primary mechanisms. We leverage simulations to interpret experimental findings, exploring electron beam properties across varying laser energies and plasma densities. Our investigations yield promising results, with measured charges of up to ∼30 nC and a maximum energy conversion efficiency exceeding 20%.