ABSTRACT
We present experimental results from the first systematic study of performance scaling with drive parameters for a magnetoinertial fusion concept. In magnetized liner inertial fusion experiments, the burn-averaged ion temperature doubles to 3.1 keV and the primary deuterium-deuterium neutron yield increases by more than an order of magnitude to 1.1×10^{13} (2 kJ deuterium-tritium equivalent) through a simultaneous increase in the applied magnetic field (from 10.4 to 15.9 T), laser preheat energy (from 0.46 to 1.2 kJ), and current coupling (from 16 to 20 MA). Individual parametric scans of the initial magnetic field and laser preheat energy show the expected trends, demonstrating the importance of magnetic insulation and the impact of the Nernst effect for this concept. A drive-current scan shows that present experiments operate close to the point where implosion stability is a limiting factor in performance, demonstrating the need to raise fuel pressure as drive current is increased. Simulations that capture these experimental trends indicate that another order of magnitude increase in yield on the Z facility is possible with additional increases of input parameters.
ABSTRACT
The role of modeling in designing new treatment protocols and instruments is discussed. A computer program for modeling laser-tissue interaction named Latis is described. Interactions are divided into the processes of laser propagation, thermal effects, material effects, and hydrodynamics. Full coupling of the processes is taken into consideration. Applications in photothermal and photomechanical laser-tissue interactions are briefly discussed. A detailed description is given of a particular application of Latis to study the effects of dynamic optical properties on dosimetry in photothermal therapy. Optical properties are functions of tissue damage, as determined by previous measurements. Results are presented for the time variation of the light distribution and damage within the tissue as the optical properties of the tissue are altered. It is found that proper accounting of dynamical optical properties is important for accurate dosimetry modeling.