학술논문

ePlas model simulations of short pulse laser target interaction experiments
Document Type
Conference
Source
2010 Abstracts IEEE International Conference on Plasma Science Plasma Science, 2010 Abstracts IEEE International Conference on. :1-1 Jun, 2010
Subject
Nuclear Engineering
Engineered Materials, Dielectrics and Plasmas
Fields, Waves and Electromagnetics
Optical pulses
Laser modes
Electrons
Gold
Geometry
Wires
Copper
Absorption
Ignition
Target tracking
Language
ISSN
0730-9244
Abstract
Summary form only given. We present recent calculations from ePLAS 1 , an implicit/hybrid simulation model applied to targets used in recent UCSD/GA experiments on Rochester's short-pulse laser. The targets are ∼1 mm long cone-headed wires of gold and copper, designed to provide data on absorption and transport of hot electrons appropriate to Fast Ignition. The code tracks light to the critical surface in laser targets, generating hot electrons. The peak intensity is ∼5xl0 18 W/cm 2 , delivered in a pulse of 10-11 picoseconds duration. The energy of the hot electrons is high enough for them to penetrate the gold cone and to propagate both outside and inside the target in a predominantly axial direction. The combination of hot electron propagation and cold electron return flow leads to net surface currents, and O(10 MG) surface magnetic fields. Simulations have been made in both cylindrical and Cartesian geometries to identify geometry dependent effects, and for comparison with the experiments. Results will be reported for dynamic ionization of the initially cold, metallic targets using both tabular and analytic EOS code additions. We will bench-mark K-alpha radiation diagnostics by comparison with simulation results from an ePLAS postprocessor.