''Follow that quarkexclamation'' (and other exclusive stories) (open access)

''Follow that quarkexclamation'' (and other exclusive stories)

Quarks are considered to be the basic constituents of matter. In a series of recent experiments, Carroll studied exclusive reactions as a means of determining the interactions between quarks. Quantum Chromo-dynamics (QCD) is the modern theory of the interaction of quarks. This theory explains how quarks are held together via the strong interaction in particles known as hadrons. Hadrons consisting of three quarks are called baryons. Hadrons made up of a quark and an antiquark are called mesons. In his lecture, Carroll describes what happens when two hadrons collide and scatter to large angles. The violence of the collision causes the gluons that bind the quarks in a particular hadron to temporarily lose their grip on particular quarks. Quarks scramble toward renewed unity with other quarks, and they undergo rearrangement, which generally results in additional new particles. A two-body exclusive reaction has occurred when the same number of particles exist before and after the collisions. At large angles these exclusive reactions are very rare. The labels on the quarks known as flavor enable the experimenter to follow the history of individual quarks in detail during these exclusive reactions. Carroll describes the equipment used in the experiment to measure short distance, …
Date: June 17, 1987
Creator: Carroll, A. S.
Object Type: Report
System: The UNT Digital Library
Technical data summary: Plan for closure of the 643-G burial ground (open access)

Technical data summary: Plan for closure of the 643-G burial ground

This report involves the actions of closing the 643-G burial ground which involves waste removal, stabilization, and capping. Remedial action involves the removing of the transuranic waste and closing of the grid wells. The closure cap for the burial site will consist of native soil, clay, and gravel. This will assure long-term physical and chemical stability. (MB)
Date: August 17, 1987
Creator: Cook, J. R.
Object Type: Report
System: The UNT Digital Library
Helical Siberian Snakes (open access)

Helical Siberian Snakes

None
Date: March 17, 1987
Creator: D., Courant E.
Object Type: Report
System: The UNT Digital Library
RHIC Decapole Correction Magnet Requirements (open access)

RHIC Decapole Correction Magnet Requirements

None
Date: August 17, 1987
Creator: F., Dell G.; Hahn, H.; Parzen, G. & Ruggiero, A. G.
Object Type: Report
System: The UNT Digital Library
Magnet technology for the Engineering Test Reactor (open access)

Magnet technology for the Engineering Test Reactor

The consideration for building an international Engineering Test Reactor emerged from the November 1985 Geneva Summit, in which President Reagan and Secretary Gorbachev called for the ''widest practical development of international cooperation'' in fusion. In parallel with the OTR design in the USSR, the FER in Japan, and the NET in Europe, the US has pursued the TIBER (Tokamak Ignition/Burn Experimental Reactor). This compact design of 3-m major radius is achievable because of high-current-density, radiation-tolerant magnets with nuclear heating rates up to 10 mW . cm/sup -3/. Full development of cable-in-conduit conductors (CICC) is seen as a credible path to achieve 40 A . mm/sup -2/ at fields of 12 T in the toroidal field (TF) coils and 14 T in the central poloidal field (PF) coils. Since neutron fluences of up to 10/sup 19/ n . cm/sup -2/ are expected in the TF coils, the unalloyed niobium-tin would be superior at 12 T. However, the central PF coil at 14 T is better shielded, so modified niobium tin would be advantageous. Polyimide insulation in the TF coils would withstand the equivalent 10/sup 10/) rads if loads in the winding pack are taken in compression. 13 refs., 7 figs., 2 …
Date: September 17, 1987
Creator: Henning, C. D. & Miller, J. R.
Object Type: Article
System: The UNT Digital Library
Thermal damage study of beryllium windows used as vacuum barriers in synchrotron radiation beamlines (open access)

Thermal damage study of beryllium windows used as vacuum barriers in synchrotron radiation beamlines

An experimental study to investigate thermal-induced damage to SSRL-designed beryllium foil windows was performed at LLNL's Laser Welding Research Facility. The primary goal of this study was to determine the threshold at which thermal-stress-induced damage occurs in these commonly used vacuum barriers. An Nd:Yag pulsed laser with cylindrical optics and a carefully designed test cell provided a test environment that closely resembles the actual beamline conditions at SSRL. Tests performed on two beryllium window geometries, with different vertical aperture dimensions but equal foil thicknesses of 0.254 mm, resulted in two focused total-power thresholds at which incipient damage was determined. For a beam spot size similar to that of the Beamline-X Wiggler Line, onset of surface damage for a 5-mm by 25-mm aperture window was observed at 170 W after 174,000 laser pulses (1.2-ms pulse at 100 pps). A second window with double the vertical aperture dimension (10 mm by 25 mm) was observed to have surface cracking after 180,000 laser pulses with 85 W impinging its front surface. It failed after approximately 1,000,000 pulses. Another window of the same type (10 mm by 25 mm) received 2,160,000 laser pulses at 74.4 W, and subsequent metallographic sectioning revealed no signs of …
Date: September 17, 1987
Creator: Holdener, F. R.; Johnson, G. L.; Karpenko, V. P.; Wiggins, R. K.; Cerino, J. A.; Dormiani, M. T. et al.
Object Type: Report
System: The UNT Digital Library
Summary of I-129 measurements in ground and surface waters (open access)

Summary of I-129 measurements in ground and surface waters

The iodine-129 content of groundwater and surface water at on-plant (Savannah River Plant) and off-plant locations has been determined at irregular intervals since 1970 using neutron activation analysis. I-129 was detected in groundwater near the Burial Ground and near the seepage basins of the Separations areas. For reference, I-129 concentrations in the groundwater can be compared to the EPA drinking water standard. At a few locations the concentrations exceeded both the existing and pending EPA drinking water standard. In surface water, Four Mile Creek was the only SRP stream found to transport significant I-129 to the Savannah River. Dilution by C-Reactor discharge and the Savannah River reduced the off-plant I-129 concentrations in river water to less than 1% of the existing EPA drinking water standard and less than 0.01% of the pending EPA drinking water standard.
Date: November 17, 1987
Creator: Kantelo, M. V.
Object Type: Report
System: The UNT Digital Library
Incorporation of toroidal boundary conditions into program POISSON (open access)

Incorporation of toroidal boundary conditions into program POISSON

A technique is developed for introduction of a boundary condition applicable to relaxation computations for magnetic problems with axial symmetry and with no sources (currents, or magnetized material) external to the boundary. The procedure as described in this note is restricted to cases in which the (toroidal) boundary will surround completely the region of physical interest but will not encompass the axis of rotational symmetry. The technique accordingly provides the opportunity of economically excluding from the relaxation process regions of no direct concern in the immediate neighborhood of the symmetry axis and hence can have useful application to annular magnetic devices with axial symmetry. The procedure adopted makes use internally of the characteristic form of the vector-potential function, in a source-free region, when expressed in toroidal coordinates. The relevant properties of associated Legendre functions of half-integral degree are summarized in this connection and their introduction into the program POISSON is outlined. Results of some test cases are included, to illustrate the application of this technique for configurations with median-plane symmetry. 8 refs., 9 figs.
Date: July 17, 1987
Creator: Laslett, L.J.; Caspi, S. & Helm, M.
Object Type: Report
System: The UNT Digital Library
Monopole strength as a probe of nuclear shape mixing (open access)

Monopole strength as a probe of nuclear shape mixing

The monopole strength, MS, within a single set of nuclear shape excitations is compared with the MS between different shapes. After misconceptions are pointed out concerning the spin dependence of B(E2) values, MS properties are juxtaposed with gamma-ray and beta-decay properties of /sup 70/Se, /sup 96/Zr, /sup 102/Pd, and the N = 60 isotones to illustrate the utility of combined investigations and evidence is given for the observation of a two-phonon octupole multiplet. Finally, consideration is given to the dominance of the /sup 3/S/sub 1/ force in producing deformation in the N > 50 1g nuclei. 23 refs., 4 figs.
Date: August 17, 1987
Creator: Meyer, R.A.
Object Type: Article
System: The UNT Digital Library
The LLNL HFTF (High-Field Test Facility): A flexible superconducting test facility for fusion magnet development (open access)

The LLNL HFTF (High-Field Test Facility): A flexible superconducting test facility for fusion magnet development

The High-Field Test Facility (HFTF) is a flexible and, in many ways, unique facility at Lawrence Livermore National Laboratory (LLNL) for providing the test capabilities needed to develop the superconducting magnet systems of the next generation fusion machines. The superconducting coil set in HFTF has been operated successfully at LLNL, but in its original configuration, its utility as a test facility was somewhat restricted and cryogenic losses were intolerable. A new cryostat for the coil set allows the magnet system to remain cold indefinitely so the system is available on short notice to provide high fields (about 11 T) inside a reasonably large test volume (0.3-m diam). The test volume is physically and thermally isolated from the coil volume, allowing test articles to be inserted and removed without disturbing the coil cryogenic volume, which is maintained by an on-line refrigerator. Indeed, with the proper precautions, it is even unnecessary to drop the field in the HFTF during such an operation. The separate test volume also allows reduced temperature operation without the expense and complication of subcooling the entire coil set (about 20-t cold mass). The HFTF has thus become a key facility in the LLNL magnet development program, where the …
Date: September 17, 1987
Creator: Miller, J. R.; Chaplin, M. R.; Leber, R. L. & Rosdahl, A. R.
Object Type: Article
System: The UNT Digital Library
Suppression of the uranium-hydrogen reaction using high-dose carbon implantation (open access)

Suppression of the uranium-hydrogen reaction using high-dose carbon implantation

We have previously reported the delay and reduction of the hydriding of uranium by implantation of oxygen. The reduced hydriding was attributed to the presence of the uranium oxide layer created near room temperature. In this paper we present results for the layers formed by implantation of 80 keV C/sup +/ to a dose of 8E17 C/cm/sup 2/. The carbide layers formed were characterized by Auger electron spectroscopy, Rutherford backscattering, and glancing angle x-ray diffraction. Hydriding properties of both non-implanted and implanted uranium were measured for 76 Torr hydrogen at 130/sup 0/C. The implanted specimens had significantly longer incubation times for the start of the reaction after exposure to hydrogen and less area participating in the reaction.
Date: April 17, 1987
Creator: Musket, R.G.
Object Type: Article
System: The UNT Digital Library
The Early Stage Of Ultra-Relativistic Heavy Ion Collisions (open access)

The Early Stage Of Ultra-Relativistic Heavy Ion Collisions

None
Date: April 17, 1987
Creator: P., Blaizot J.
Object Type: Report
System: The UNT Digital Library
Application of microwave energy for in-drum solidification of simulated precipitation sludge (open access)

Application of microwave energy for in-drum solidification of simulated precipitation sludge

The application of microwave energy for in-container solidification of simulated transuranic contaminated precipitation sludges has been tested. Results indicate volume reductions to 83% are achievable by the continuous feeding of pre-dried sludge into a waste container while applying microwave energy. An economic evaluation was completed showing achievable volume and weight reductions to 87% compared with a current immobilization process for wet sludge. 7 refs., 15 figs., 16 tabs.
Date: August 17, 1987
Creator: Petersen, R. D.; Johnson, A. J.; Swanson, S. D. & Thomas, R. L. (ed.)
Object Type: Report
System: The UNT Digital Library
Button/Plate Yielding (open access)

Button/Plate Yielding

An aluminum button and plate were yielded to compare the experimental and calculated button to plate stress ratios. Using the fact that compressive stress is directly proportional to area and load, the calculated button to plate stress ratio is equal to the plate to button area ratio for a constant load. The loads that caused the button and plate to yield were estimated from a load test cell graph obtained from the materials testing facility. The button was simply compressed, but the plate was compressed with a steel cylinder of the same diameter as the aluminum button. The experimental and calculated stress ratios for the button and plate are the same within experimental error. The equation for the plate bearing area is therefore correct.
Date: June 17, 1987
Creator: Wintercorn, S.
Object Type: Report
System: The UNT Digital Library