Spatial profile of accelerated electrons from ponderomotive scattering in hydrogen cluster targets

We study the laser-driven acceleration of electrons from overdense hydrogen clusters to energies up 13 MeV in laser forward direction and several hundreds keV an outer ring-like structure. The use cryogenic allows for high repetition-rate operation examination influence source parameters like temperature gas flow. structure accelerated electrons, originating interaction, that is robust against change target can be observed low electron densities ca. 3$\times$10$^{16}$ cm$^{-3}$. For higher densities, additional central spot observed. Utilizing 3D-PIC simulations, it revealed both populations mainly stem ponderomotive scattering.