2001 Annual Report
The LLE 2001 Annual Report is a summary of the Laboratory’s work during fiscal year 2001 in support of direct-drive inertial fusion research, participation in the Department of Energy’s Stewardship Science Program (SSP), operation of the National Laser Users’ Facility (NLUF), and programs involving education of high school, undergraduate, and graduate students.
Highlights of this year’s effort include significant improvements in direct-drive capsule implosion performance with full beam smoothing on OMEGA; measurements to assess the effects of shock heating on the stability of direct-drive inertial fusion capsules; the development of a measurement-based model of the stagnated core and fuel-pusher mix; the development of a model, including hot-spot dynamics, to predict the minimum drive-energy requirements to achieve direct-drive ignition on the NIF; the measurement of the highest combination of electron density and temperature in Ar-doped deuterium-filled gas capsules; test of the feasibility of using extended x-ray absorption fine structure (EXAFS) to characterize the properties of solid materials shocked at pressures up to a few Mbar; multibeam laser-plasma interaction experiments designed to resemble future direct-drive laser fusion implosions on the NIF; and the development of improved plasma diagnostic capabilities for OMEGA and for future NIF experiments including the implementation of an improved-spatial-resolution neutron imaging system on OMEGA in collaboration with Commissariat à L’Énergie Atomique (CEA) of France and scientists from Los Alamos National Laboratory (LANL).
In addition, this annual report includes a summary of experiments conducted on OMEGA by teams from Lawrence Livermore National Laboratory, LANL, Sandia National Laboratory (SNL), CEA, and teams from several universities and private industry under the NLUF Program. Also included are LLE’s laser and optical materials research and development activities, i.e., the development of a UV fiber-optic beam delivery system for OMEGA beam diagnostics; preliminary work on NIF’s 2-D SSD beam smoothing system; and the modeling of the beam-smoothing performance of ultrafast picket-fence pulses for the NIF.
Finally, this report summarizes LLE’s education programs, which range from high school summer internships to graduate student research. As the only major university participant in the National ICF Program, education continues to be an important mission for the Laboratory.
Table of Contents
- Executive Summary
- Theory of the Hot-Spot Dynamics and Deceleration-Phase Instability of Imploding ICF Capsules
- The Effect of Shock Heating on the Stability of Laser-Driven Targets
- Spherical Cavity Expansion in Material with Densification
- Design and Performance of a Selectable-Rate Streak-Camera Deflection Ramp Generator
- Unique High-Bandwidth, UV Fiber Delivery System for OMEGA Diagnostics Applications
- Fabrication and Properties of an Ultrafast NbN Hot-Electron Single-Photon Detector
- Preliminary Design of NIF 2-D SSD
- Characterization of Direct-Drive-Implosion Core Conditions on OMEGA with Time-Resolved Ar K-Shell Spectroscopy
- Study of Direct-Drive, DT-Gas-Filled-Plastic-Capsule Implosions Using Nuclear Diagnostics on OMEGA
- A Consistent Measurement-Based Picture of Core-Mix in Direct-Drive Implosions on OMEGA
- High-Resolution Neutron Imaging of Laser-Imploded DT Targets
- The Smoothing Performance of Ultrafast Pickets on the NIF
- Tests of EXAFS on OMEGA: Feasibility for Shock-Heating Measurements
- Microhardness and Indentation Fracture of Potassium Dihydrogen Phosphate (KDP)
- A Self-Calibrating, Multichannel Streak Camera for Inertial Confinement Fusion Applications
- Evolution of Shell Nonuniformities Near Peak Compression of a Spherical Implosion
- Multibeam Stimulated Brillouin Scattering from Hot Solid-Target Plasmas
- Hot-Electron Effect in Superconductors and Its Applications for Radiation Sensors
- Scaling Law for Marginal Ignition
- Wide-Dynamic-Range “Neutron Bang Time” Detector on OMEGA
- Functional Damage Thresholds of Hafnia/Silica Coating Designs for the NIF Laser
- High-Gain Direct Drive Target Designs for the National Ignition Facility
- Ultrafast Optoelectronic Interface for Digital Superconducting Electronics
- Optimizing the Fabrication of Polyimide Shells
- LLE’s Summer High School Research Program
- FY01 Laser Facility Report
- National Laser Users’ Facility News
- Publications and Conference Presentations