Figure 3
From: Enhancing laser-driven proton acceleration by using micro-pillar arrays at high drive energy
The energy distribution of electrons escaping from micro-pillar targets (solid symbols) irradiated at 2 × 1017 W/cm2 was measured and compared with those from a flat target (empty symbols). Different planar film materials were used: copper (red), silver (black) and gold (blue). The experimental data were fitted to a Boltzmann distribution (dashed lines).
