Ion acceleration is considered to be one of the main applications of high power laser systems that are being projected, have been built, or are already operational around the world. Laser driven ion acceleration is not only attractive from the point of view of potential applications of high energy ion beams, but also from the point of view of investigations of fundamental aspects of laser-matter interaction and advanced concepts of particle acceleration. In this talk we, first, discuss an experimental study of ion acceleration using the BELLA petawatt laser, and, second, the results of 3D PIC modeling of laser ion acceleration from near critical density (NCD) targets.
We report on parameter scans with >100 shots that were enabled by the high repetition rate (1 Hz) of the laser, targetry and diagnostic. The experiments were conducted in the large laser spot size regime, where we found that the geometry of the interaction plays an important role in providing uniform plasma heating across the focal plane. The laser pulse duration scans (35 - 600 fs) were instrumental in revealing this geometric effect. Particle-in-Cell (PIC) simulations were used to gain insight into the dynamics of the interaction and field structure.
Laser-driven ion acceleration via the Magnetic Vortex Acceleration (MVA) scheme was explored using 3D Warp+PICSAR and WarpX PIC simulation codes. We discuss the properties of the Magnetic Vortex Acceleration mechanism revealed through the 3D PIC simulations and its optimization through matching of laser pulse focusing and target density.
The work was supported by the US DOE Office of Science (HEP, FES, and LDRD) under Contract No. DE-AC02-05CH11231.
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