NASA Scientific and Technical Aerospace Reports

with other subsystems. Currents on the target chamber from the pulsed power systems are well below the background noise
currents.
NTIS
Background Noise; Currents; Leakage; Pulse Duration; Power Conditioning
20040068280 Lawrence Livermore National Lab., Livermore, CA
Extraction Kickers and Modulators for the Advanced Hydrodynamic Facility
Walstrom, P. L.; Cook, E. G.; Jun. 12, 2001; In English
Report No.(s): DE2003-15004787; UCRL-JC-144172; No Copyright; Avail: National Technical Information Service (NTIS)
In order to exploit the full potential of the Advanced Hydrodynamic Facility (AHF) facility to produce a time sequence
of proton transmission radiographs throughout the dynamic event, a kicker/modulator for extraction from the 50 GeV ring that
is capable of generating a string of 25 pulse pairs at arbitrary times within a total time duration of 100 microseconds or more
is desired. The full range of desired pulse-train requirements cannot be met with the commonly used pulse-forming cables or
networks (PFNs) switched with thyratrons. The preferred modulator design approach at present is a transformer voltage-adder
concept with primary-side pulses formed with MOSFET-switched capacitors. This modulator will be a scale-up of an existing
modulator that has been developed by Lawrence Livermore National Laboratory for use in DARHT, an electron induction
accelerator facility at Los Alamos National Laboratory. Before the voltage-adder concept can be adopted for use in AHF, a
working prototype that meets the AHF requirements for the pulse voltage, current, rise and fall time, and total pulse number
must be built and tested. Additional requirements for pulse-to-pulse flattop height variation and baseline shift must also be met.
A development and testing plan for the voltage-adder kicker modulator for AHF is described.
NTIS
Capacitors; Electron Accelerators; Extraction; Field Effect Transistors; Protons
20040068285 Lawrence Livermore National Lab., Livermore, CA
Investigation into the Role of Initial Conditions on Rayleigh-Taylor Instabilities by Low Atwood Experiments and
Simulations
Mueschke, N.; Andrews, M.; Schilling, O.; Jul. 16, 2003; In English
Report No.(s): DE2003-15004813; UCRL-ID-154412; No Copyright; Avail: National Technical Information Service (NTIS)
The primary goal of the research being conducted this summer is to investigate the role of initial conditions in the
development of a two fluid mix driven by Rayleigh-Taylor instability. The effects of initial conditions will be studied through
the use of experimental facilities located at the Buoyancy-Driven Mixing Lab at Texas A&M University and through high
resolution direct numerical simulations of the experiment by the MIRANDA code developed at Lawrence Livermore National
Lab.
NTIS
Research Facilities; Simulation; Taylor Instability
20040068288 Rutherford Appleton Lab., Oxford, UK
Investigation of a Low-Energy X-Ray Spectrometer Based on Pixellated Hybrid Silicon Detectors
Seller, P.; Feb. 2004; 18 pp.; In English
Report No.(s): PB2004-105658; Copyright; Avail: National Technical Information Service (NTIS)
No abstract available
Silicon; X Ray Spectrometers
20040068295 Lawrence Livermore National Lab., Livermore, CA
Slow Radio-Frequency Processing of Large Oil Shale Volumes to Produce Petroleum-like Shale Oil
Burnham, A. K.; Aug. 20, 2003; In English
Report No.(s): DE2003-15004663; UCRL-ID-155045; No Copyright; Avail: National Technical Information Service (NTIS)
A process is proposed to convert oil shale by radio frequency heating over a period of months to years to create a product
similar to natural petroleum. Electrodes would be placed in drill holes, either vertical or horizontal, and a radio frequency
chosen so that the penetration depth of the radio waves is of the order of tens to hundreds of meters. A combination of excess
volume production and overburden compaction drives the oil and gas from the shale into the drill holes, where it is pumped
to the surface. Electrical energy for the process could be provided initially by excess regional capacity, especially off-peak
power, which would generate (approx)3 x 10(exp 5) bbl/day of synthetic crude oil, depending on shale grade. The electricity
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