Back to Labs Accomplishments Home page
Supernova remnants are radiative shocks that exhibit a large amount of structure and may play a role in star formation. In experiments with the University of Texas using the Z-Beamlet laser, we modeled the growth of such structures by tracking the evolution of perturbations induced on the surface of nearly spherical blast waves (see image at left). A unique feature of our experiments is the ability to induce perturbations of different wavelengths using wire arrays. The measured perturbation decay rates are in substantial agreement with a theory proposed by Vishniac in the 1980s. (1600)
Our 3D electromagnetics modeling code, Emphasis/Nevada, was used to model the detailed, time-dependent performance of the complex water convolute component in the ZR accelerator. Emphasis/Nevada simulates full electromagnetics behavior using a cutting-edge, finite-element formulation. Using standard analysis techniques, we also constructed an electrical circuit model of the convolute for the ZR system model. The 3D modeling identified a problem with the water convolute that we corrected in the final design, thereby improving the performance of ZR by more than a million amperes.
Following its successful deployment of flash X-ray radiography on the Armando sub-crit experiment at the Nevada Test Site, the Advanced Radiographic Technologies Program has met a corporate level 2 milestone with the completed construction of the Radiographic Integrated Test Stand (RITS). The RITS-6 accelerator is designed to deliver 11 MV, 125 kA, 60-ns pulses for flash X-ray radiography source development. Future experiments to be conducted in collaboration with the UK’s Atomic Weapons Establishment will attempt to obtain world-record X-ray intensities from a pulse-power-driven architecture.
Wire array z-pinches driven at up to 20 MA on the Z accelerator are the world’s most powerful and energetic laboratory source of soft X-rays. Recent progress in meeting the radiation symmetry requirements for inertial confinement fusion (ICF) has now been complemented by experiments that shaped the soft X-ray radiation-drive time history. Nested wire arrays were shown to meet the pulse shape requirements for high-gain inertial fusion at yields of 290-900 MJ, compatible with future applications of low-cost z-pinch technology to stockpile stewardship and fusion energy applications. (1600)