A Survey of Applications of Computer Technology at the Laboratory for Laser Energetics

Author: Jacques Delettrez (University of Rochester, Laboratory for Laser Energetics (LLE))

Abstract

The Laboratory for Laser Energetics (LLE) has been in the forefront of direct-drive inertial confinement fusion (ICF) research, which has as the ultimate goal of energy production using nuclear fusion. At LLE, the 25-kJ, 60-beam OMEGA laser irradiates targets with diameters slightly smaller than a millimeter with a pulse lasting one to three nanoseconds. For direct-drive ICF to succeed, tight requirements are imposed on the uniformity, timing, and pointing of the laser illumination and on the smoothness of the targets. Good quality experiments require that shots in a single campaign taken over the span of several months have the same pulse energy and temporal shape. Numerical simulations are needed to understand the complex physics of target implosions and to design experiments. Extensive use of computer technology has helped reach these goals. On the "hardware" side of the research program, computers are used to model the laser propagation and amplification, design phase plates to control the focal spot and streak cameras to measure the pulse, control the laser and shot sequence, and diagnose the uniformity of the inner ice surface in cryogenic targets. Experiments are backed by a large simulation capability that include one- and two-dimensional hydrodynamic codes to model the implosions, two laser-plasma interaction codes, and a hybrid PIC code that tackles the physics introduced by the new high-intensity, short-pulse OMEGA EP laser. Examples of these computer technology applications will be discussed with an emphasis on implosion simulations.

This work was supported by the U.S. Department of Energy Office of Inertial Confinement Fusion under Cooperative Agreement No. DE-FC52-92SF19460, the University of Rochester, and the New York State Energy Research and Development Authority. The support of DOE does not constitute an endorsement by DOE of the views expressed in this article.