Laser-Produced Plasma Experiments and Particle in Cell Simulation to Study Thrust Conversion Processes in a Laser Fusion Rocket

An experiment is conducted to study the thrust conversion process of a laser fusion rocket (LFR) in a scaled-down manner. The temporal evolution of laser-produced plasma clouds (LPC) expanding in a dipole magnetic field is examined and the thrust conversion efficiency is estimated. For comparative purposes, numerical analyses of plasma behaviour in a dipole magnetic field are also performed using a three-dimensional (3D) hybrid particle-in-cell (PIC) code. An overall good agreement between the experimental and simulation data is found. It is also found that a thrust conversion efficiency as high as 60% is possible in the scaled-down model considered here. The experiments will be very useful in developing LFR designs and testing the basic features of the large-scale simulative LFR experiments proposed for the National Ignition Facility (NIF).