Heavy Neutral Beam Probe for edge plasma analysis in Tokamaks. Annual progress report, December 1, 1992--November 30, 1993 (open access)

Heavy Neutral Beam Probe for edge plasma analysis in Tokamaks. Annual progress report, December 1, 1992--November 30, 1993

The contents of this report present the progress achieved to date on the Heavy Neutral Beam Probe project. This effort is an international collaboration in magnetic confinement fusion energy research sponsored by the US Department of Energy, Office of Energy Research (Confinement Systems Division) and the Centre Canadien de Fusion Magnetique (CCFM). The overall objective of the effort is to develop and apply a neutral particle beam to the study of edge plasma dynamics in discharges on the Tokamak de Varennes (TdeV) facility in Montreal, Canada. To achieve this goal, a research and development project was established to produce the necessary hardware to make such measurements and meet the scheduling requirements of the program. At present the project is in the middle of its second budget period with the instrumentation on-site at TdeV. The first half of this budget period was used to complete total system tests at InterScience, Inc., dismantle and ship the hardware to TdeV, re-assemble and install the HNBP on the tokamak. Integration of the diagnostic into the TdeV facility has progressed to the point of first beam production and measurement on the plasma. At this time, the HNBP system is undergoing final de-bugging prior to re-start …
Date: September 3, 1993
Creator: Castracane, J.; Saravia, E.; Beckstead, J. & Aceto, S.
Object Type: Report
System: The UNT Digital Library
Using laser absorption spectroscopy to monitor composition and physical properties of metal vapors (open access)

Using laser absorption spectroscopy to monitor composition and physical properties of metal vapors

The Atomic Vapor Laser Isotope Separation (AVLIS) program has been using laser absorption spectroscopy to monitor vapor densities for over 15 years. Laser absorption spectroscopy has proven itself to be an accurate and reliable method to monitor both density and composition. During this time the diagnostic has moved from a research tool toward a robust component of a process control system. The hardware used for this diagnostic is discussed elsewhere at this symposium. This paper describes how the laser absorption spectroscopy diagnostic is used as a component of a process control system as well as supplying detailed measurements on vapor densities, composition, flow velocity, internal and kinetic temperatures, and constituent distributions. Examples will be drawn from the uranium AVLIS program. In addition potential applications such as composition control in the production of metal matrix composites or aircraft alloys will be discussed.
Date: September 3, 1993
Creator: Berzins, L. V.
Object Type: Article
System: The UNT Digital Library
Mean time between failures (MTBF) and availability of the Gyrotron system used on the Microwave Tokamak Experiment at Lawrence Livermore National Laboratory (open access)

Mean time between failures (MTBF) and availability of the Gyrotron system used on the Microwave Tokamak Experiment at Lawrence Livermore National Laboratory

This paper presents an analysis of the mean time between failures (MTBF) and availability history of the Varian VGT8140, 400 Watt, 140 GHz Gyrotron that was operated on the Microwave Tokamak Experiment (MTX) at the Lawrence Livermore National Laboratory (LLNL).
Date: September 3, 1993
Creator: Ferguson, S. W.; Jackson, M. C. & Seilhymer, D. B.
Object Type: Article
System: The UNT Digital Library
Neutron detector for fusion reaction-rate measurements (open access)

Neutron detector for fusion reaction-rate measurements

We have developed a fast, sensitive neutron detector for recording the fusion reaction-rate history of inertial-confinement fusion (ICF) experiments. The detector is based on the fast rise-time of a commercial plastic scintillator (BC-422) and has a response < 25-ps FWHM. A thin piece of scintillator material acts as a neutron-to- light converter. A zoom lens images light from the scintillator surface to a high-speed (15 ps) optical streak camera for recording. The zoom lens allows the scintillator to be positioned between 1 and 50 cm from a target. The camera simulaneously records an optical fiducial pulse which allows the camera time base to be calibrated relative to the incident laser power. Bursts of x rays formed by focusing 20-ps, 2.5-TW laser pulses onto gold disk targets demonstrate the detector resolution to be < 25 ps. We have recorded burn histories for deuterium/tritium-filled targets producing as few as 3 {times} 10{sup 7} neutrons.
Date: September 3, 1993
Creator: Lerche, R. A.; Phillion, D. W. & Tietbohl, G. L.
Object Type: Article
System: The UNT Digital Library
Storing data from fusion experiments at the National Storage Laboratory (open access)

Storing data from fusion experiments at the National Storage Laboratory

The National Storage Laboratory (NSL) at the National Energy Research Supercomputer Center (NERSC) is a prototype facility which is developing data storage and retrieval techniques using hardware that includes a hierarchy of storage devices. The ultimate goal is to store terabytes of data and achieve rapid retrieval times compatible with the type of media where the data is stored. Files stored in the NSL are accessed directly using the Network File System (NFS); in the future, the Andrew File System (AFS) is expected to be used. System level control of files is available using the File Transfer Protocol (FTP) or a set of program-callable routines. We have experimented with storing and retrieving data from fusion experiments at LLNL and at General Atomics in San Diego, California, using computers running UNIX and VMS operating systems. We discuss some issues associated with accessing files whose names are known, but which are not immediately available, the time required for retrieval, and other pertinent parameters.
Date: September 3, 1993
Creator: Butner, D. N. & Meyer, W. H.
Object Type: Article
System: The UNT Digital Library