A5083222131- Laser-Plasma Interactions and Diagnostics
- Nuclear Physics and Applications
- Laser-induced spectroscopy and plasma
- X-ray Spectroscopy and Fluorescence Analysis
- Advanced X-ray Imaging Techniques
- High-pressure geophysics and materials
- Ion-surface interactions and analysis
- Advanced Optical Sensing Technologies
- Advanced X-ray and CT Imaging
- Atomic and Molecular Physics
- Ionosphere and magnetosphere dynamics
- Energetic Materials and Combustion
- Optical Systems and Laser Technology
- Radiation Detection and Scintillator Technologies
- Combustion and Detonation Processes
Lawrence Livermore National Laboratory
2016-2024
The Crystal Backlighter Imager (CBI) is a quasi-monochromatic, near-normal incidence, spherically bent crystal imager developed for the National Ignition Facility (NIF), which will allow inertial confinement fusion capsule implosions to be radiographed close stagnation. This not possible using standard pinhole-based area-backlighter configuration, as self-emission from hotspot overwhelms backlighter signal in final stages of implosion. CBI mitigates broadband hot spot by extremely narrow...
Current two-dimensional X-ray imaging at the National Ignition Facility (NIF) uses time resolved pinhole cameras with ∼10-25 μm pinholes. This method has limitations in smallest resolvable features that can be imaged reasonable photon statistics for inertial confinement fusion (ICF) applications. ICF sources have a broadband self-emission spectrum causes images obtained, through thin foil filters, to contain similarly complicating interpretation of structure source. In order study phenomena...
A new time-resolved opacity spectrometer (OpSpecTR) is currently under development for the National Ignition Facility (NIF) campaign. The utilizes Icarus version 2 (IV2) hybridized complementary metal–oxide–semiconductor sensors to collect gated data at time of transmission signal, unlocking ability higher-temperature measurements on NIF. Experimental conditions achieve higher temperatures are feasible; however, backgrounds will dominate collected by current time-integrating spectrometer....
When compared with the National Ignition Facility's (NIF) original soft x-ray opacity spectrometer, which used a convex cylindrical design, an elliptically shaped design has helped to increase signal-to-noise ratio and eliminated nearly all reflections from alternate crystal planes. The success of elliptical geometry in experiments driven new spectral range covering 520-1100 eV. coupled primary geometry, spans 1000-2100 eV, sub-keV helps cover full iron L-shell major oxygen transitions...
High-energy-density laser facilities and advances in dynamic compression techniques have expanded access to material states the Terapascal regime relevant inertial confinement fusion, planetary science, geophysics. However, experimentally determining temperature these extreme conditions has remained a difficult challenge. Extended X-ray Absorption Fine Structure (EXAFS), referring modulations x-ray absorption above an edge from photoelectrons’ interactions with neighboring atoms, proven be...
Supra-thermal (>100 keV) electrons generated by laser plasma interactions can be detrimental to the performance of ignition experiments conducted on National Ignition Facility (NIF). On a NIF shot, amount is estimated measuring hard X-rays passing through hohlraum wall. The primary sources hot in are Stimulated Raman Scattering (SRS) and two plasmon decay (TPD). While SRS well diagnosed NIF, there has been no diagnosis TPD. We have designed implemented new diagnostic characterize time...
The National Ignition Facility (NIF) at Lawrence Livermore Laboratory (LLNL) uses the world’s largest and most energetic laser system to explore High-Energy-Density (HED) physics. Historically, experiments NIF could not radiograph an Inertial Confinement Fusion (ICF) experiment late times due self-emission from capsule. Crystal Backlighter Imager diagnostic (CBI) fielded on in 2017 has allowed radiography of ICF capsules times. This capability is very narrow bandwidth imaging system, which...
The multi-channel Kirkpatrick-Baez microscope (KBM), currently in use at the National Ignition Facility (NIF), uses grazing incidence multilayer crystals to focus x-rays form an image. This diagnostic produces four images with a ~11x magnification, designed energy response of 10.2 ±1.5 keV We present new calibration KBM using molybdenum (W, Z = 42) x-ray microfocus source measure spectral instrument over its field view. Our results variation and dependence on coalignment imaging channels,...