High Energy Laser Driven Electron Acceleration

The effects of introducing a gas density gradient just after the accelerating gas cell was tested with the intention of observing an increase in the energy of electrons and an improvement on several other parameters of the beam after acceleration (divergence, relative peak width, and beam pointing).

It was found that a density gradient was able to accelerate the electrons to higher energies owing to the longer acceleration lengths, with the final energy being up to 85% larger than the initial energy when shots were averaged out every 5 points. The pointing of the beam relative to the laser axis was also found to stabilise around the zero point after 70 shots, whereas the divergence and relative width of the monoenergetic peaks (∆E/E)remained relatively constant, with values of ∼ 1mrad and ∼ 15% the maximum energy respectively.