Effect of proton initial locations on proton acceleration by interaction of laser and plain target

For further understanding of the proton acceleration by target normal sheath acceleration (TNSA), the effect of the proton initial locations on the quality of the proton beam is investigated by two-dimensional particle-in-cell (2D-PIC) code Flips2D. The simulation results show that the effect of the proton initial locations on the proton quality is very significant. The divergence of protons is related to their initial locations in transverse direction. The farther away the protons is from the laser axis, the larger the proton divergence can be received.