Continuation of Full-Scale Three-Dimensional Numerical Experiments on High-Intensity Particle and Laser Beam-Matter Interactions

University Of California-Los Angeles, Los Angeles CA

Investigators

Abstract

The goal of this research is broadly aimed at advancing the understanding of the complex interactions that occur when intense lasers and particle beams propagate through plasmas. Very accurate simulations are used to study these interactions, focusing on developing concrete concepts for new classes of ultra-compact particle accelerators. Particle accelerators are some of the most complex and expensive tools used for scientific discovery. They are used to discover the most fundamental particles in nature, to understand fundamental processes in biology, to probe and develop materials, and to treat cancer. A plasma, an ionized gas of charged particles, is sometimes called the fourth state of matter. When a short pulse of very bright light or a short pulse of a high current of electrons are sent through a plasma a wake or wave is created. The crests and troughs in this wake move near the speed of light, and charged particles can then surf this wake and also accelerate to near the speed of light. This research will focus on understanding how the laser-plasma interactions can be controlled to lead to the creation of the plasma wake and the acceleration of the injected beam to very high energies. The research will use a combination of accurate simulations and theory to advance the understanding of basic high-energy density science in the area of intense laser and particle beam plasma interactions, and on how to manipulate the six dimensional phase space of particle beams using plasma wave wakefields. This will include production of exotic and bright beams, and efficient acceleration of positrons. This research relies on the particle-in-cell method which simulates the trajectories of individual electrons and ions in the plasma as they interact through their self-consistently generated electric and magnetic fields and any externally applied fields. This discovery driven research will also help to provide the understanding needed to develop plasma-based accelerator stages for use in high energy physics colliders, next-generation light sources, medicine, and homeland security. This effort blends basic and discovery driven research with particle-in-cell simulations including full-scale 3D modeling of current, near term, and far term experiments. The simulations have repeatedly been shown to provide a test bed for theoretical ideas and new concepts and a method for guiding ongoing and future experiments. The research continues to include benchmarking codes against well-diagnosed experiments and each other. High-fidelity full-scale modeling using the nations largest computers provides a means to extrapolate parameters into regimes that will not be accessible to experiments for years to come. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.