Filter-fluorescer diagnostic system for the National Ignition Facility

Abstract

An early filter-fluorescer diagnostic system is being fielded at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) to measure the amount of hard x rays (20<hν<150 keV) generated in laser fusion experiments. From these measurements we hope to quantify the number of hot electrons produced in laser fusion experiments. The measurement of hot electron production is important for ignition experiments because these electrons can preheat the fuel capsule. Hot electrons can also be employed in experimentation by preheating hydrodynamic packages or by driving plasmas out of equilibrium. The experimental apparatus, data collection, analysis and calibration issues are discussed. Expected data signal levels are predicted and discussed.