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TDR liquid level detection program

Description: A data acquisition system for monitoring the SRS reactor Supplemental Safety System (SSS) during chargeback testing has been installed. The system is based on liquid level detection by means of time domain reflectometry. Software developed for the system allows data to be collected from a digitizing oscilloscope by an IBM AT computer, displayed and stored as needed by the user. The software is menu- driven to facilitate user interaction.
Date: July 1, 1996
Creator: Reeves, G. & Toole, B.
Partner: UNT Libraries Government Documents Department

New perspectives on substorm injections

Description: There has been significant progress in understanding substorm injections since the Third International Conference on Substorms in 1996. Progress has come from a combination of new theories, quantitative modeling, and observations--particularly multi-satellite observations. There is now mounting evidence that fast convective flows are the mechanism that directly couples substorm processes in the mid tail, where reconnection occurs, with substorm processes the inner magnetosphere where Pi2 pulsations, auroral breakups, and substorm injections occur. This paper presents evidence that those flows combined with an earthward-propagating compressional wave are responsible for substorm injections and discusses how that model can account for various substorm injection signatures.
Date: December 1, 1998
Creator: Reeves, G.D.
Partner: UNT Libraries Government Documents Department

ULTRA SECURE HIGH RELIABILITY WIRELESS RADIATION MONITOR

Description: Radiation monitoring in nuclear facilities is essential to safe operation of the equipment as well as protecting personnel. In specific, typical air monitoring of radioactive gases or particulate involves complex systems of valves, pumps, piping and electronics. The challenge is to measure a representative sample in areas that are radioactively contaminated. Running cables and piping to these locations is very expensive due to the containment requirements. Penetration into and out of an airborne or containment area is complex and costly. The process rooms are built with thick rebar-enforced concrete walls with glove box containment chambers inside. Figure 1 shows high temperature radiation resistance cabling entering the top of a typical glove box. In some case, the entire processing area must be contained in a 'hot cell' where the only access into the chamber is via manipulators. An example is shown in Figure 2. A short range wireless network provides an ideal communication link for transmitting the data from the radiation sensor to a 'clean area', or area absent of any radiation fields or radioactive contamination. Radiation monitoring systems that protect personnel and equipment must meet stringent codes and standards due to the consequences of failure. At first glance a wired system would seem more desirable. Concerns with wireless communication include latency, jamming, spoofing, man in the middle attacks, and hacking. The Department of Energy's Savannah River National Laboratory (SRNL) has developed a prototype wireless radiation air monitoring system that address many of the concerns with wireless and allows quick deployment in radiation and contamination areas. It is stand alone and only requires a standard 120 VAC, 60 Hz power source. It is designed to be mounted or portable. The wireless link uses a National Security Agency (NSA) Suite B compliant wireless network from Fortress Technologies that is considered robust enough ...
Date: August 3, 2011
Creator: Cordaro, J.; Shull, D.; Farrar, M. & Reeves, G.
Partner: UNT Libraries Government Documents Department

ELECTRONICS UPGRADE TO THE SAVANNAH RIVER NATIONAL LABORATORY COULOMETER FOR PLUTONIUM AND NEPTUNIUM ASSAY

Description: The Savannah River Site (SRS) has the analytical measurement capability to perform high-precision plutonium concentration measurements by controlled-potential coulometry. State-of-the-art controlled-potential coulometers were designed and fabricated by the Savannah River National Laboratory and installed in the Analytical Laboratories process control laboratory. The Analytical Laboratories uses coulometry for routine accountability measurements of and for verification of standard preparations used to calibrate other plutonium measurement systems routinely applied to process control, nuclear safety, and other accountability applications. The SRNL Coulometer has a demonstrated measurement reliability of {approx}0.05% for 10 mg samples. The system has also been applied to the characterization of neptunium standard solutions with a comparable reliability. The SRNL coulometer features: a patented current integration system; continuous electrical calibration versus Faraday's Constants and Ohm's Law; the control-potential adjustment technique for enhanced application of the Nernst Equation; a wide operating room temperature range; and a fully automated instrument control and data acquisition capability. Systems have been supplied to the International Atomic Energy Agency (IAEA), Russia, Japanese Atomic Energy Agency (JAEA) and the New Brunswick Laboratory (NBL). The most recent vintage of electronics was based on early 1990's integrated circuits. Many of the components are no longer available. At the request of the IAEA and the Department of State, SRNL has completed an electronics upgrade of their controlled-potential coulometer design. Three systems have built with the new design, one for the IAEA which was installed at SAL in May 2011, one system for Los Alamos National Laboratory, (LANL) and one for the SRS Analytical Laboratory. The LANL and SRS systems are undergoing startup testing with installation scheduled for this summer.
Date: July 8, 2011
Creator: Cordaro, J.; Holland, M.; Reeves, G.; Nichols, S. & Kruzner, A.
Partner: UNT Libraries Government Documents Department

Observations of magnetospheric substorms occurring with no apparent solar wind/IMF trigger

Description: An outstanding topic in magnetospheric physics is whether substorms are always externally triggered by disturbances in either the interplanetary magnetic field or solar wind, or whether they can also occur solely as the result of an internal magnetospheric instability. Over the past decade, arguments have been made on both sides of this issue. Horwitz and McPherron have shown examples of substorm onsets which they claimed were not externally triggered. However, as pointed out by Lyons, there are several problems associated with these studies that make their results somewhat inconclusive. In particular, in the McPherron et al. study, fluctuations in the B{sub y} component were not considered as possible triggers. Furthermore, Lyons suggests that the sharp decreases in the AL index during intervals of steady IMF/solar wind, are not substorms at all but rather that they are just enhancements of the convection driven DP2 current system that are often observed to occur during steady magnetospheric convection events. In the present study, we utilize a much more comprehensive dataset (consisting of particle data from the Los Alamos energetic particle detectors at geosynchronous orbit, IMP 8 magnetometer and plasma data, Viking UV auroral imager data, mid-latitude Pi2 pulsation data, ground magnetometer data and ISEE1 magnetic field and energetic particle data) to show as unambiguously as possible that typical substorms can indeed occur in the absence of an identifiable trigger in the solar wind/IMF.
Date: March 1, 1996
Creator: Henderson, M.G.; Reeves, G.D.; Belian, R.D. & Murphree, J.S.
Partner: UNT Libraries Government Documents Department

A quantitative test of different magnetic field models using conjunctions between DMSP and geosynchronous orbit

Description: We report here on a study which tests the magnetic field line mapping between geosynchronous orbit and the ionosphere. The mapping is determined both observationally and from five magnetospheric magnetic field models. The mapping is tested observationally by comparing electron energy spectra obtained by the Magnetospheric Plasma Analyzer (MPA) at geosynchronous orbit and by the DMSP spacecraft. Because the orbits are nearly perpendicular, in general, the spectra match well for only a few seconds providing a good determination of when DMSP crosses the geosynchronous drift shell. In this way the mapping between geosynchronous orbit and the ionosphere can be determined to better than one degree. We then compare the measured magnetic footpoints of geosynchronous orbit with the footpoints predicted by five magnetospheric field models: Tsyganenko-89, Tsyganenko-87, Tsyganenko-82, Oslen-Pfitzer, and Hilmer-Voigt. Based on a set of over 100 measured magnetic conjunctions we find that, in general, there are significant differences between the mappings predicted by various magnetic field models but that there is no clear ``winner`` in predicting the observed mapping. We find that the range of magnetic latitudes at which we measure conjunctions is much broader than the range of latitudes which the models can accommodate. This lack of range is common to all magnetic field models tested. Although there are certainly cases where the models are not sufficiently stretched, we find that on average all magnetic field models tested are too stretched. This technique provides an excellent opportunity for testing future magnetic field models and for determining the appropriate parameterizations for those models. 21 refs., 4 figs.
Date: March 1, 1996
Creator: Reeves, G.D.; Weiss, L.A.; Thomsen, M.F. & McComas, D.J.
Partner: UNT Libraries Government Documents Department

Measuring the magnetic connectivity of the geosynchronous region of the magnetosphere

Description: This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The purpose of this project was to determine the magnetic connectivity of the geosynchronous region of the magnetosphere to the auroral zone in the polar ionosphere in order to test and refine current magnetospheric magnetic field models. The authors used plasma data from LANL instruments on three geosynchronous satellites and from USAF instruments on three low-altitude, polar-orbiting, DMSP satellites. Magnetic connectivity is tested by comparing plasma energy spectra at DMSP and geosynchronous satellites when they are in near conjunction. The times of closest conjugacy are used to evaluate the field models. They developed the tools for each step of the process and applied them to the study of a one-week test set of conjunctions. They automated the analysis tools and applied them to four months of two-satellite observations. This produced a database of about 130 definitive magnetic conjunctions. They compared this database with the predictions of the widely-used Tsyganenko magnetic field model and showed that in most cases one of the various parameterizations of the model could reproduce the observed field line connection. Further, they explored various measurables (e.g., magnetospheric activity indices or the geosynchronous field orientation) that might point to the appropriate parameterization of the model for these conjunctions, and ultimately, for arbitrary times.
Date: March 1, 1996
Creator: Thomsen, M.; Hones, E.; McComas, D.; Reeves, G. & Weiss, L.
Partner: UNT Libraries Government Documents Department

Automated leak test systems

Description: An automated leak test system for tritium shipping containers has been developed at Westinghouse Savannah River Co. (WSRC). The leak detection system employs a computer controlled helium detector which allows an operator to enter key information when prompted. The software for controlling the tests and the equipment apparatus were both designed and manufactured at the Savannah River Technology Center within WSRC. Recertification Test: Every twelve months, the pressure vessel portion of the shipping container itself must undergo a rigorous recertification leak test. After an empty pressure vessel (shipping container) is assembled, it is placed into one of six stainless steel belljars for helium leak testing. The belljars are fashioned in row much the same as assembly line arrangement. Post-load Test: A post-load leak test is performed upon reservoirs that have been filled with tritium and placed inside the shipping containers mentioned above. These leak tests are performed by a rate-of-rise method where the area around the shipping container seals is evacuated, valved off from the vacuum pump, and then the vacuum pressure is monitored over a two-minute period. The Post Load Leak Test is a quality verification test to ensure that the shipping container has been correctly assembled. 2 figs.
Date: September 15, 1997
Creator: Cordaro, J.V.; Thompson, W.D. & Reeves, G.
Partner: UNT Libraries Government Documents Department

Observational testing of magnetospheric magnetic field models at geosynchronous orbit

Description: Empirical mode which estimate the magnetic field direction and magnitude at any point within the magnetosphere under a variety of conditions play an important role in space weather forecasting. We report here on a number of different studies aimed at quantitatively evaluating these models, and in particular the Tsyganenko T89a model. The models are evaluated in two basic ways: (1) by comparing the range of magnetic field tilt angles observed at geosynchronous orbit with the ranges predicted for the same locations by the models; and (2) by comparing the observed magnetic field mapping between the ionosphere and geosynchronous orbit (using two-satellite magnetic field conjunctions) with the model predictions at the same locations. We find that while the T89a model predicts reasonably well the basic variation in tilt angle with local time and permits a range of field inclinations adequate to encompass the majority of observed angles on the dawn, dusk, and night sides, it is unable to reproduce the range of inclinations on the dayside. The model also predicts a smaller magnetic latitude range of geosynchronous field line footpoints than the observed two-satellite mapping indicate. Together, these results suggest that the next generation of field models should allow a greater range of stretching, especially in local time sectors away from midnight. It is important to note, however, that any increased range should encompass less-stretched configurations: although there are certainly cases where the models are not sufficiently stretched, we find that on average all magnetic field models tested, including T89a, are too stretched. Finally, in investigating how well the observed degree of field stretch was ordered by various magnetospheric indices, we find that the tilt of the field at geosynchronous orbit is a promising candidate for the incorporation into future models.
Date: September 1, 1996
Creator: Weiss, L.A.; Thomsen, M.F.; Reeves, G.D. & McComas, D.J.
Partner: UNT Libraries Government Documents Department

AEM/STEM analysis of vapor-deposited multilayered laser targets

Description: S(TEM) examinations were made to augment other types of measurements of absolute density. The structure of the 5 ..mu..m thick layers of aluminum and gold on aluminum laminate gold substrate was examined to establish film integrity, to characterize the microstructure, as well as to estimate the surface roughness of this multilayer material.
Date: January 1, 1983
Creator: Johnson, K.A.; Staudhammer, K.P.; Reeves, G.A. & Vesser, L.R.
Partner: UNT Libraries Government Documents Department

Composition and energetics of solar flare particle events measured by satellites, 1989--1991

Description: The Synchronous Orbit Particle Analyzer (SOPA), on board the satellite 1989-046 and others, has detected ions from carbon through nickel at energies from 2 to 50 MeV in the great solar energetic particle events of the current solar cycle. Energetic protons from the same events have been detected by the Charged Particle Analyzer (CPA) on board the satellite 1984-129 and others. We present here a collection of data from these various instruments that includes events of 1989, 1990, and 1991. We demonstrate the association of the events detected by the satellites with solar flares, and examine local solar wind features that in some instances alter the flux. We determine the ionic composition of the events, and compare these compositions among the various events and with those events, and compare these compositions among the various events and with those found in events of previous solar cycles. We obtain time-histories of the energetic particle fluxes, resolved both by ion species and by energy range. These detailed histories are of use, in conjunction with other data, in determining the parameters of the acceleration region.
Date: January 1, 1991
Creator: Gisler, G.R.; Belian, R.D.; Cayton, T.E. & Reeves, G.D.
Partner: UNT Libraries Government Documents Department

Impedance-matching experiments using high-pressure, laser-driven shock waves

Description: A high-power laser was used to produce shock waves with pressures of 300 to 700 GPa. A series of impedance-matching experiments on aluminum-copper systems with 10% accuracy indicate several areas in which the experiment can be improved to reduce the errors. Several such improvements are now being made, including upgrading both the laser and recording systems and modifying the target characterization techniques.
Date: January 1, 1981
Creator: Veeser, L.R.; Reeves, G.A.; Holmes, N.C.; Trainor, R.J. & Anderson, R.A.
Partner: UNT Libraries Government Documents Department

MAINTAINING HIGH RESOLUTION MASS SPECTROMETRY CAPABILITIES FOR NATIONAL NUCLEAR SECURITY ADMINISTRATION APPLICATIONS

Description: The Department of Energy (DOE) National Nuclear Security Administration (NNSA) has a specialized need for analyzing low mass gas species at very high resolutions. The currently preferred analytical method is electromagnetic sector mass spectrometry. This method allows the NNSA Nuclear Security Enterprise (NSE) to resolve species of similar masses down to acceptable minimum detection limits (MDLs). Some examples of these similar masses are helium-4/deuterium and carbon monoxide/nitrogen. Through the 1980s and 1990s, there were two vendors who supplied and supported these instruments. However, with declining procurements and down turns in the economy, the supply of instruments, service and spare parts from these vendors has become less available, and in some cases, nonexistent. The largest NSE user of this capability is the Savannah River Site (SRS), located near Aiken, South Carolina. The Research and Development Engineering (R&DE) Group in the Savannah River National Laboratory (SRNL) investigated the areas of instrument support that were needed to extend the life cycle of these aging instruments. Their conclusions, as to the focus areas of electromagnetic sector mass spectrometers to address, in order of priority, were electronics, software and hardware. Over the past 3-5 years, the R&DE Group has designed state of the art electronics and software that will allow high resolution legacy mass spectrometers, critical to the NNSA mission, to be operated for the foreseeable future. The funding support for this effort has been from several sources, including the SRS Defense Programs, NNSA Readiness Campaign, Pantex Plant and Sandia National Laboratory. To date, electronics systems have been upgraded on one development system at SRNL, two production systems at Pantex and one production system at Sandia National Laboratory. An NSE working group meets periodically to review strategies going forward. The R&DE Group has also applied their work to the electronics for a Thermal Ionization Mass ...
Date: June 6, 2011
Creator: Wyrick, S.; Cordaro, J.; Reeves, G.; Mcintosh, J.; Mauldin, C.; Tietze, K. et al.
Partner: UNT Libraries Government Documents Department

PERFORMANCE OF THE SAVANNAH RIVER SITE COULOMETER FOR NEPTUNIUM PROCESSACCOUNTABILITY AND NEPTUNIUM OXIDE PRODUCT CHARACTERIZATION

Description: The Savannah River Site's (SRS) H-Area B-Line (HB-Line) nuclear facility is processing neptunium solutions for stabilization as an oxide. The oxide will eventually be reprocessed and fabricated into target material and the 237Np irradiated to produce {sup 238}Pu in support of National Aeronautics and Space Administration space program missions. As part of nuclear materials accountability, solution concentrations were measured using a high-precision controlled-potential coulometer developed and manufactured at the SRS for plutonium accountability measurements. The Savannah River Site Coulometer system and measurement methodology for plutonium meets performance standards in ISO 12183-2005, 'Controlled-Potential Coulometric Assay of Plutonium'. The Department of Energy (DOE) does not produce or supply a neptunium metal certified reference material, which makes qualifying a measurement method and determining accuracy and precision difficult. Testing and performance of the Savannah River Site Coulometer indicates that it can be used to measure neptunium process solutions and dissolved neptunium oxide without purification for material control and accountability purposes. Savannah River Site's Material Control and Accountability organization has accepted the method uncertainty for accountability and product characterization measurements.
Date: June 4, 2008
Creator: Holland, M; Patterson Nuessle, P; Sheldon Nichols, S; Joe Cordaro, J & George Reeves, G
Partner: UNT Libraries Government Documents Department

Superconducting properties of Tl-Ba-Ca-Cu-O films on silver substrates

Description: Films of Ba-Ca-Cu-O have been rf magnetron sputtered onto Consil 995 substrates. A post deposition anneal in an over pressure of Tl produces the superconducting 1212 and 2212 phases. Varying the annealing procedures changes the electrical properties of the final films dramatically. Dynamic impedance, a novel approach to the electrical characterization of these films on a conductive substrate is discussed and compared with SEM, XRD and RBS measurements as a function of differing annealing protocols. 3 refs., 9 figs.
Date: January 1, 1990
Creator: Dye, R.C.; Arendt, P.N.; Martin, J.A.; Hubbard, K.M.; Elliott, N. & Reeves, G.
Partner: UNT Libraries Government Documents Department

An observational test of magnetospheric magnetic field mapping

Description: The distortion of the geomagnetic field is a key signature of the response of the magnetosphere to the solar wind input. A number of empirical models have been devised to estimate the magnetic field direction and magnitude at any point within the magnetosphere under a variety of conditions. We describe a technique whereby the field-line mapping predicted by such models is tested by matching measurements of magnetospheric plasma energy spectra obtained by Los Alamos instruments at geosynchronous orbit with spectra obtained by instruments on the polar-orbiting DMSP satellites (at an altitude of about 800 km) at times when the two satellites are in approximate magnetic conjugacy. With up to three geosynchronous satellites and as many as four DMSP satellites in operation at any given time, there are a very large number of such two-satellite conjunctions, allowing the model mappings to be tested under a wide range of local times and geomagnetic activity. Preliminary results from the application of this technique are presented for one week of data from March, 1991.
Date: July 1, 1994
Creator: Weiss, L. A.; Thomsen, M. F.; Reeves, G. D.; Hones, E. W. & McComas, D. J.
Partner: UNT Libraries Government Documents Department

An observational test of magnetospheric field models at geosynchronous orbit

Description: The configuration of the geomagnetic field is an indicator of the response of the magnetosphere to the solar wind input. A number of empirical magnetospheric field models are currently in use which estimate the magnetic field direction and magnitude at any point within the magnetosphere under a variety of conditions. Here, the global nature of the Tsyganenko 89 [Tsyganenko, 1989] magnetospheric magnetic field model is tested by comparison of the model-predicted field orientations with the field orientations derived simultaneously at two different locations in geosynchronous orbit from the axis of symmetry of the plasma electron distribution function (30 eV--40 keV). The results for the particular time interval studied are inconclusive because the Tsyganenko 89 model does not describe the field at one of the satellites well enough, but the procedure itself appears promising.
Date: July 1, 1994
Creator: Thomsen, M. F.; Weiss, L. A.; McComas, D. J.; Moldwin, M. B. & Reeves, G. D.
Partner: UNT Libraries Government Documents Department

Long term behavior of trapped relativistic electrons and their correlation with solar wind speed

Description: We examine Los Alamos energetic electron data from 1979 through the present to show long term trends in the trapped relativistic electron populations at geosynchronous Earth orbit. Such populations are thought to be associated with high-speed solar wind structures typically present near solar minimum. We will show that high-energy electron fluxes, E > 1.4 MeV, displayed a solar-like cycle of about 10.5 years, but that the behavior is out of phase with the sunspot cycle. We will also compare relativistic electrons during the cycle with solar wind speed from the MIT plasma analyzers on IMP-8. It will be shown that relativistic electrons correlate well with high solar winds only during limited, short periods of time. We will also confirm the observation that the higher-energy electrons occur with a longer delay after the establishment of the high-speed solar wind. Comparison of our data with previously published data indicate that the higher the solar wind speed, the sooner the relativistic electrons occur.
Date: December 1995
Creator: Belian, R. D.; Cayton, T. E.; Christensen, R. A.; Ingraham, J. C. & Reeves, G. D.
Partner: UNT Libraries Government Documents Department

The energy spectrometer for particles (ESP): Instrument description and orbital performance

Description: The ESP detector is functionally described, along with the pertinent orbital and spin properties of the spacecraft that supports it. The phoswiched plastic/BGO scintillators sensor design, electronic implementation, and resulting data types are recounted, and the ground calibration procedures are reported. Several illustrative examples of data are given, including the solar proton event of 29 September 1989, and the nearly periodic episodes of high relativistic electron flux that are associated with solar coronal holes which have been a dominant feature of the space weather over the past few years. 2 refs., 10 figs., 1 tab.
Date: December 31, 1994
Creator: Meier, M.M.; Belian, R.D.; Cayton, T.E.; Christensen, R.; Garcia, B.; Grace, K. et al.
Partner: UNT Libraries Government Documents Department

Energetic neutral atom imaging with the Polar CEPPAD/IPS instrument: Initial forward modeling results

Description: Although the primary function of the CEP-PAD/IPS instrument on Polar is the measurement of energetic ions in-situ, it has also proven to be a very capable Energetic neutral Atom (ENA) imager. Raw ENA images are currently being constructed on a routine basis with a temporal resolution of minutes during both active and quiet times. However, while analyses of these images by themselves provide much information on the spatial distribution and dynamics of the energetic ion population in the ring current, detailed modeling is required to extract the actual ion distributions. In this paper, the authors present the initial results of forward modeling an IPS ENA image obtained during a small geo-magnetic storm on June 9, 1997. The equatorial ion distribution inferred with this technique reproduces the expected large noon/midnight and dawn/dusk asymmetries. The limitations of the model are discussed and a number of modifications to the basic forward modeling technique are proposed which should significantly improve its performance in future studies.
Date: December 31, 1997
Creator: Henderson, M.G.; Reeves, G.D.; Moore, K.R.; Spence, H.E.; Jorgensen, A.M.; Fennell, J.F. et al.
Partner: UNT Libraries Government Documents Department

Particle acceleration from reconnection in the geomagnetic tail

Description: Acceleration of charged particles in the near geomagnetic tail, associated with a dynamic magnetic reconnection process, was investigated by a combined effort of data analysis, using Los Alamos data from geosynchronous orbit, MHD modeling of the dynamic evolution of the magnetotail, and test particle tracing in the electric and magnetic fields obtained from the MHD simulation.
Date: August 1, 1997
Creator: Birn, J.; Borovsky, J.E.; Thomsen, M.F.; McComas, D.J.; Reeves, G.D.; Belian, R.D. et al.
Partner: UNT Libraries Government Documents Department

The energy spectrometer for particles (ESP): Instrument description and orbital performance

Description: The ESP detector is functionally described, along with the pertinent orbital and spin properties of the spacecraft that supports it. The phoswiched plastic/BGO scintillators sensor design, electronic implementation, and resulting data types are recounted, and the ground calibration procedures are reported. Several illustrative examples of data are given, including the solar proton event of 29 September 1989, and the nearly periodic episodes of high relativistic electron flux that are associated with solar coronal holes which have been a dominant feature of the space weather over the past few years.
Date: December 31, 1994
Creator: Meier, M.; Belian, D.; Cayton, T.; Christensen, R.; Garcia, B.; Grace, K. et al.
Partner: UNT Libraries Government Documents Department

Physical vapor deposited aluminum foils from high energy density physics experiments

Description: Fabrication of cylindrical aluminum load foils and graded thickness aluminum vacuum opening switch foils is described. Load foils are vaporized by joule heating and imploded by J {times} B forces to stagnate on axis and create soft x-rays. Plasma flow switch foils are mounted to shunt the vacuum power flow channel of a coaxial gun and are vaporized by joule heating. The resultant graded density plasma is magnetically driven down the annular power flow channel. Opening switch action occurs when the shunt plasma crosses a load slot in the center conductor. These foil components have been used in both the Pegasus and Procyon experiments.
Date: September 1, 1995
Creator: Barthell, B.L.; Anderson, W.E.; Gomez, V.M.; Henneke, B.F.; Moore, J.E.; Reeves, G.A. et al.
Partner: UNT Libraries Government Documents Department

Solar particle events during the rising phase of solar cycle 22

Description: The solar energetic particle events since early 1989 have been among the most intense and hardest in almost three decades. These particles were measured by several Los Alamos instruments on satellites in geosynchronous orbit. Proton fluxes and spectral slopes as measured by the CPA instrument are reported for 1989 and 1990. The composition of heavy (Z {approx} 6--28) energetic ({approx}2--50 MeV) ions as measured by the SOPA instrument is presented for the October 1989 event. 13 refs., 4 figs.
Date: January 1, 1991
Creator: Reedy, R.C.; Cayton, T.E.; Belian, R.D.; Gary, S.P.; Gisler, G.R.; Reeves, G.D. et al.
Partner: UNT Libraries Government Documents Department