Laser-driven collisionless shock acceleration of protons

Paper in proceeding, 2016

Experimental and numerical results have shown that collisionless shock acceleration is promis- ing for generation of high energy proton beams. There are many potential applications for such beams, for example: isotope generation for medical applications, ion therapy and proton radio- graphy. In this work, we use 1D1P Eulerian Vlasov-Maxwell simulations to study shock wave acceleration. Vlasov-Maxwell modeling allows for high resolution of the distribution function and is highly suitable in cases where effects of low-density tails in the distribution function need to be resolved accurately. We find that combining collisionless shock acceleration with a strong, quasi-stationary sheath- field may be a way to reach even higher maximum proton energies and optimize the ion spec- trum. We show that a layered plasma target with a combination of light and heavy ions leads to a strong quasi-static sheath-field, which induces an enhancement of the energy of shock-wave accelerated ions, without broadening their energy spectrum, if the heavy ion layer has high density.