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One of the major forms of scientific and technical communication is a poster session found at many scientific and technical conferences. Most students are not exposed to this type of communication early in their academic careers, and those who choose to enter into a non-technical major may never be exposed to this style of presentation. We report the results of a program to increase scientific literacy...
The Physics program at the United States Coast Guard Academy has implemented a completely revised introductory physics sequence utilizing state-of-the-art techniques in physics education. With active student engagement based on socio-cultural constructivism at its core, techniques such as Just-inTime Teaching and Peer Instruction along with the testing effect are paramount to this new model. Here,...
The refurbishment of Sandia's Z generator, completed in late 2007, represents a significant enhancement in its capabilities. In addition to increased operational efficiency and reliability, up to twice the previous energy can be stored in its present capacitors, allowing for greater load current and coupled energy1. Despite losses occurring near the load, enhancements of current of ∼ 15% and load...
Z-pinch driven plasmas produce the highest yield among K-shell line emission sources1. Recently measured yields on the refurbished Z generator (∼20 MA) include: 270 kJ for Al (E>1 keV); 75 kJ for stainless steel (SS, E>5 keV); and 25 kJ for Cu (E>5 KeV). Gas puff experiments are planned for the summer of 2012 and predictions for the Ar (E>3.1 keV) K-shell yield are > 300 kJ. Clearly...
A new hohlraum configuration for radiation physics/ICF was proposed [B. Jones et al., PRL 104, 125001 (2010)]. Multiple compact (mm-scale) planar wire array (PWA) sources that surround a central hohlraum allow reduced hohlraum surface area and potentially provide a hotter x-ray environment than in a double-ended scheme with cylindrical arrays. The current multiplication technique became possible because...
Advances in diagnostics at the refurbished Z facility at Sandia National Laboratories (SNL) now allow spatially and temporally resolved spectra to be obtained, with improved signal-to-noise ratios. Z-pinch simulation models have also improved, due both to substantial advances in the understanding of the underlying physics, and to the development of more detailed and accurate atomic databases. We will...
Summary form only given. K-shell X-rays have been studied with various materials at the 20-MA (pre-refurbished) Z accelerator. This paper presents results obtained for the ablation dynamics and stagnation physics of single and nested copper z-pinches with varying initial load diameters. Monochromatic imaging and shadowgraphy provide detailed information regarding the ablation of the wires and the...
The increasing use of charged particle radiotherapy (CPT) in many countries will require British oncologists to establish their personal viewpoints on this subject in order to advise their patients regarding the merits or otherwise of obtaining such treatment abroad. This paper covers the advantages and some disadvantages of CPT in many anatomical locations on the basis of the achievable dose distributions...
Summary form only given. The time-history of the ion-kinetic energy Ekion throughout the stagnation phase of a neon-puff, 500 ns, 600 kA, Z-pinch implosion was determined. The X-ray spectroscopic system provides a resolving power of 6700 and four consecutive time gated (~1 ns) spectra. A simultaneous axial imaging allows for studying the ion kinetic energy at 0.1-mm-resolution along the pinch column...
A 1D radiation hydrodynamics code with non-LTE collisional radiative population dynamics is used to simulate stainless steel wire array pinch implosions on the ZR generator at Sandia National Laboratories. To account for the wire ablation phase, the initial array position is treated as a time dependent mass source. The spatial extent of the evaporation and radial acceleration forms a thin outer boundary...
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