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Transport in compact tori (open access)

Transport in compact tori

The parameter B/sub e//nr/sub p/ (here, B/sub e/ is applied magnetic field strength, nr/sub p/ is the plasma density-radius product) is proposed as a key parameter for spheromak heating studies. If B/sub e//nr/sub p/ is too large, increased magnetic fluctuations limit heating; low B/sub e//nr/sub p/ value results in excessive radiation losses. An optimum range appears to be B/sub e//nr/sub p/ approx. 1 to 5 x 10/sup -20/ Wb.
Date: February 23, 1983
Creator: Miley, G. H.
System: The UNT Digital Library
Current technology of particle physics detectors (open access)

Current technology of particle physics detectors

A brief discussion is given of the characteristics required of new accelerator facilities, leading into a discussion of the required detectors, including position sensitive detectors, particle identification, and calorimeters. (LEW)
Date: June 23, 1986
Creator: Ludlam, T. W.
System: The UNT Digital Library
Aperture studies with Patricia and Racetrack on simple lattices containing SSC dipoles (open access)

Aperture studies with Patricia and Racetrack on simple lattices containing SSC dipoles

The PATRICIA and RACETRACK particle tracking programs have been compared by tracking on a simple lattice. The dynamic aperture was found to decrease as the number of passes through the lattice per run increased from 20 to approx. 300, and it remained constant for longer runs. The dynamic apertures found by the two programs are consistent. The dependence of the dynamic aperture on horizontal tune near a decapole resonance was investigated. RACETRACK and PATRICIA showed decreases in the aperture on opposite sides of the resonance. A second set of studies was made with PATRICIA in which the dynamic apertures of lattices consisting of cells of the types used for the Reference Designs Study were determined when random multipole errors of the dipoles were included. The dependence of aperture on the number of cells in the lattice was determined. Finally, a comparison of magnet types suggested for the SSC was made by determining the aperture of lattices containing these magnets.
Date: June 23, 1984
Creator: Dell, G.F.; Leemann, B. & Willeke, F.
System: The UNT Digital Library
Symmetry issues in a class of ion beam targets using sufficiently short direct drive pulses (open access)

Symmetry issues in a class of ion beam targets using sufficiently short direct drive pulses

Controlling asymmetries in direct drive ion beam targets depends upon the ability to control the effects of residual target asymmetries after an appropriate illumination scheme has already been utilized. A class of modified ion beam targets where residual asymmetries are ameliorated is considered. The illumination scheme used is an axially symmetric one convenient for reactor designs. Residual asymmetries are controlled by limiting the radial motion of the radius R/sub dep/ of peak ion energy deposition. Limiting the motion of R/sub dep/ is achieved by lengthening the time scale t/sub s/ where changes in R/sub dep/ adversely affect asymmetries. In our example, t/sub s/ becomes longer than the duration ..delta..t/sub D/ of the entire direct drive pulse train (t/sub s/ > ..delta..t/sub D/).
Date: October 23, 1986
Creator: Mark, J.W.K. & Lindl, J.D.
System: The UNT Digital Library
Progress on achieving the ICF conditions needed for high gain (open access)

Progress on achieving the ICF conditions needed for high gain

Progress during the past two years has moved us much closer to demonstrating the scientific and technological requirements for high gain ICF in the laboratory. This progress has been made possible by operating at the third harmonic of 1..mu..m light which dramatically reduces concern about hot electrons and by advances in diagnostics such as 100 ps x-ray framing cameras which greatly increase the data available from each experiment. Making use of many of these new capabilities, major improvements in confinement conditions have been achieved for ICF implosions. In particular, in an optimized hohlraum on Nova, radiation driven implosions with convergence ratio in excess of 30 (volume compression /approximately/3 /times/ 10/sup 4/) have performed essentially as predicted by spherical implosion calculations. This paper presents these results as well as examples of advances in several other areas and discusses the implications for the future of ICF with lasers and heavy ion beam drivers. 8 refs., 10 figs.
Date: December 23, 1988
Creator: Lindl, J.D.
System: The UNT Digital Library
Radioactive fallout from the Chernobyl nuclear reactor accident (open access)

Radioactive fallout from the Chernobyl nuclear reactor accident

Following the accident at the nuclear reactor at Chernobyl, in the Soviet Union on April 26, 1986, we performed a variety of measurements to determine the level of the radioactive fallout on the western United States. We used gamma-spectroscopy to analyze air filters from the areas around Lawrence Livermore National Laboratory (LLNL), California, and Barrow and Fairbanks, Alaska. Milk from California and imported vegetables were also analyzed. The levels of the various fission products detected were far below the maximum permissible concentration levels.
Date: March 23, 1987
Creator: Beiriger, J.M.; Failor, R.A.; Marsh, K.V. & Shaw, G.E.
System: The UNT Digital Library
Novel probe for determining the size and position of a relativistic electron beam (open access)

Novel probe for determining the size and position of a relativistic electron beam

In order to determine the size and position of a relativistic electron beam inside the wiggler magnetic field of a Free Electron Laser (FEL), we have developed a new probe which intercepts the electron beam on a high Z target and monitors the resulting bremsstrahlung radiation. The probe is designed to move along the entire three meters of the wiggler. This FEL is designed to operate in the microwave region (2 to 8 mm) and the interaction region is an oversized waveguide with a cross section 3 cm x 9.8 cm. The axial probe moves inside this waveguide. The probe stops the electron beam on a Tantalum target and the resulting x-rays are scattered in the forward direction. A scintillator behind the beam stop reacts to the x-rays and emits visible light in the region where the x-rays strike. An array of fiber optics behind the scintillator transmits the visible light to a Reticon camera system which images the visible pattern from the scintillator. Processing the optical image is done by digitizing and storing the image and/or recording the image on video tape. Resolution and performance of this probe will be discussed.
Date: July 23, 1984
Creator: Orzechowski, T.J.; Koehler, H.; Edwards, W.; Nelson, M. & Marshall, B.
System: The UNT Digital Library
pi. /sup -/p. -->. K/sub s//sup 0/K/sub s//sup 0/n at 22 Gev/c and a Systematic Study of the 2/sup + +/ and 0/sup + +/ Meson Spectrum (open access)

pi. /sup -/p. -->. K/sub s//sup 0/K/sub s//sup 0/n at 22 Gev/c and a Systematic Study of the 2/sup + +/ and 0/sup + +/ Meson Spectrum

A coupled channel analysis has been carried out using amplitudes of the K/sub s//sup 0/K/sub s//sup 0/ system produced in the reaction ..pi../sup -/p ..-->.. K/sub s//sup 0/K/sub s//sup 0/n at 22 Gev/c, which contained about 40,000 events in the low-t region (absolute value of t-tmin < 0.1 Gev/sup 2/). The I/sup G/ = 0/sup +/, J/sup PC/ = 0/sup + +/, 2/sup + +/, 4/sup + +/ amplitudes from this analysis is considered, together with available data from other experiments in channels with the same quantum numbers in order to determine which 0/sup + +/ and 2/sup + +/ isoscalar mesons have significant pseudoscalar-pseudoscalar couplings. It is found that we need one pole for the 4/sup + +/ amplitudes while the 2/sup + +/ needs five poles and the 0/sup + +/ needs 7 poles.
Date: June 23, 1987
Creator: Longacre, R. S.; Etkin, A.; Foley, K. J.; Love, W. A.; Morris, T. W.; Platner, E. D. et al.
System: The UNT Digital Library
Analyzing power measurements in high-P/sub perpendicular to//sup 2/ p-p elastic scattering (open access)

Analyzing power measurements in high-P/sub perpendicular to//sup 2/ p-p elastic scattering

The analyzing power in 28 GeV/c proton-proton elastic scattering was measured at P/sub perpendicular to//sup 2/ = 5.95 and 6.56 (GEV/c)/sup 2/ y/sub g/ a polarized proton target and an unpolarized proton beam at the Brookhaven National Laboratory AGS. Results indicate that the analyzing power, A, is rising sharply with P/sub perpendicular to//sup 2/. Previous measurements of the analyzing power, A, in p + p ..-->.. p + p suggested a rise in A at large-P/sub perpendicular to//sup 2/, but the statistical uncertainty in the highest point at P/sub perpendicular to//sup 2/ = 5.95 (GeV/c)/sup 2/ made it impossible to determine the magnitude of the increase. In an effort to clarify this situation, we made new measurements of A at P/sub perpendicular to//sup 2/ = 5.95 and 6.56 (GeV/c)/sup 2/. An unpolarized beam of typically 5 x 10/sup 10/ 28 GeV/c protons from the AGS at Brookhaven National Laboratory was incident upon the University of Michigan polarized proton target. This target contains irradiated ammonia beads cooled to 0.5/sup 0/K by a /sup 3/He-/sup 4/He evaporation refrigerator, in a 2.5 T magnetic field. The polarizing transitions are driven by a 70 GHz microwave system. The polarization of the hydrogen protons is …
Date: May 23, 1984
Creator: Raymond, R. S.; Brown, K. A.; Bruni, R. J.; Cameron, P. R.; Crabb, D. G.; Cummings, R. L. et al.
System: The UNT Digital Library
Manufacture and evaluation of Nb/sub 3/Sn conductors fabricated by the MJR method (open access)

Manufacture and evaluation of Nb/sub 3/Sn conductors fabricated by the MJR method

The bronze matrix/niobium filament process has become established as a commercially viable method for producing multifilamentary Nb/sub 3/Sn superconductors. This paper describes a new method, the Modified Jelly-Roll (MJR) approach, which can produce a structure similar to that in a conventionally fabricated multifilamentary Nb/sub 3/Sn conductor. This approach utilizes alternate sheets of niobium expanded metal and bronze, which are rolled into a jelly-roll configuration and then extruded. During extrusion and subsequent drawing, the junctures in the niobium are elongated and the material develops a filamentary structure. This method may offer significant advantages in terms of reduced fabrication time and cost over the conventional approach. Results of a manufacturing development program will be presented in which two lengths of conductor were made to High-Field Test Facility conductor specifications. In addition, critical current and transition temperature measurements of the sub-elements used to construct the HFTF-type lengths will be reported.
Date: November 23, 1982
Creator: McDonald, W. K.; Curtis, C. W.; Scanlan, R. M.; Larbalestier, D. C.; Marken, K. & Smathers, D. B.
System: The UNT Digital Library
COBRA-WC pretest predictions and post-test analysis of the FOTA temperature distribution during FFTF natural-circulation transients (open access)

COBRA-WC pretest predictions and post-test analysis of the FOTA temperature distribution during FFTF natural-circulation transients

The natural circulation tests of the Fast Flux Test Facility (FFTF) demonstrated a safe and stable transition from forced convection to natural convection and showed that natural convection may adequately remove decay heat from the reactor core. The COBRA-WC computer code was developed by the Pacific Northwest laboratory (PNL) to account for buoyancy-induced coolant flow redistribution and interassembly heat transfer, effects that become important in mitigating temperature gradients and reducing reactor core temperatures when coolant flow rate in the core is low. This report presents work sponsored by the US Department of Energy (DOE) with the objective of checking the validity of COBRA-WC during the first 220 seconds (sec) of the FFTF natural-circulation (plant-startup) tests using recorded data from two instrumented Fuel Open Test Assemblies (FOTAs). Comparison of COBRA-WC predictions of the FOTA data is a part of the final confirmation of the COBRA-WC methodology for core natural-convection analysis.
Date: June 23, 1982
Creator: Khan, E. U.; George, T. L. & Rector, D. R.
System: The UNT Digital Library
Winter experience of a passive solar retrofit. Final technical report (open access)

Winter experience of a passive solar retrofit. Final technical report

An older home in St. Louis had 2 inch foam insulation added to the outside of masonry walls with stucco exterior finish applied. The south wall was modified so that there is a gross solar collection area of 26.2 m/sup 2/, with 13.2 m/sup 2/ of greenhouse, 8.6 m/sup 2/ of direct gain and 4.4 m/sup 2/ of Trombe components. The performance of the building and its data acquisition system are described. (MHR)
Date: December 23, 1980
Creator: Michels, T. I. & Andes, F. S.
System: The UNT Digital Library
Isolating human DNA repair genes using rodent-cell mutants (open access)

Isolating human DNA repair genes using rodent-cell mutants

The DNA repair systems of rodent and human cells appear to be at least as complex genetically as those in lower eukaryotes and bacteria. The use of mutant lines of rodent cells as a means of identifying human repair genes by functional complementation offers a new approach toward studying the role of repair in mutagenesis and carcinogenesis. In each of six cases examined using hybrid cells, specific human chromosomes have been identified that correct CHO cell mutations affecting repair of damage from uv or ionizing radiations. This finding suggests that both the repair genes and proteins may be virtually interchangeable between rodent and human cells. Using cosmid vectors, human repair genes that map to chromosome 19 have cloned as functional sequences: ERCC2 and XRCC1. ERCC1 was found to have homology with the yeast excision repair gene RAD10. Transformants of repair-deficient cell lines carrying the corresponding human gene show efficient correction of repair capacity by all criteria examined. 39 refs., 1 fig., 1 tab.
Date: March 23, 1987
Creator: Thompson, L.H.; Weber, C.A.; Brookman, K.W.; Salazar, E.P.; Stewart, S.A. & Mitchell, D.L.
System: The UNT Digital Library
lambda. N effective interaction (open access)

lambda. N effective interaction

A combination of theoretical estimates, based on a ..lambda..N potential model, and phenomenological analysis of hypernuclear data is used to determine a set of four P/sub N/s/sub ..lambda../ two-body matrix elements which characterize the spin dependence of the ..lambda..N interaction in the p shell. The central spin-spin and the ..lambda.. spin-orbit matrix elements are most strongly constrained by existing data. The spin dependence is weak in the sense that s/sub ..lambda../ doublet splittings are predicted to be of order 100 keV except for the special case of /sub ..lambda..//sup 7/Li where the central spin-spin interaction dominates and the ground-state doublet separation is likely to be about 600 keV. The results of recent (K/sup -/, ..pi../sup -/..gamma..) experiments at the Brookhaven AGS are interpreted in terms of the ..lambda..N effective interaction.
Date: May 23, 1984
Creator: Millener, D. J.
System: The UNT Digital Library
Final optic protection designs for ICF containment chambers (open access)

Final optic protection designs for ICF containment chambers

The output from a laser-driven high-fain ICF target in the laboratory microfusion facility (LMF) target chamber could produce enough x-rays, shrapnel, and debris to severely damage the laser's final optics. If the final optics were left unprotected, the replacement and reinstallation costs for each beam would exceed $40K. Assuming the laser has 68 beams, the replacement costs for each shot could reach $2.7M. To avoid these excessive costs, we must design a reliable optics protection system. This requires that we define the hazardous environment to which the optics are exposed. The geometrical layout for the 68 beams of the 10 megajoule laser shows the final optics placed at 25 meters from the target. The final optic will be a 2--5 cm thick debris shield ($40K each) which will be placed in front of a $200K focussing lens. Each of the 68 beams will deliver 150 kJ of 0.35 ..mu..m (3..omega..) light and will consist of either a 4 /times/ 4 or a 2 /times/ 8 array of beamlets, with each beamlet aperture having dimensions of 29 cm /times/ 29cm. This produces a 3..omega.. energy density at the final optic of 12J/cm/sup 2/ average and 225-30J/cm/sup 2/peak. 8 refs., 4 figs., …
Date: August 23, 1988
Creator: Nilson, David G. & Woodworth, John G.
System: The UNT Digital Library
Laser-induced damage measurements with 266-nm pulses (open access)

Laser-induced damage measurements with 266-nm pulses

The results of a survey of laser-induced damage thresholds for optical components at 266 nm are reported. The thresholds were measured at two pulse durations--0.150 ns and 1.0 ns. The 30 samples tested include four commercial dielectric reflectors, three metallic reflectors, two anti-reflection films, a series of eight half-wave oxide and fluoride films, and twelve bare surfaces (fluoride crystals, silica, sapphire, BK-7 glass, CD*A and KDP). The 266-nm pulses were obtained by frequency-quadrupling a Nd:YAG, glass laser. Equivalent plane imagery and calorimetry were used to measure the peak fluence of each of the UV pulses with an accuracy of +- 15%; the uncertainty in the threshold determinations is typically +- 30%.
Date: January 23, 1980
Creator: Deaton, T. F. & Smith, W. L.
System: The UNT Digital Library
ATA beam director experiment (open access)

ATA beam director experiment

This report describes beam director elements for an experiment at the Advanced Test Accelerator. The elements described include a vernier magnet for beam aiming, an achromat magnet, and an isolation system for the beam interface. These components are built at small scale for concept testing. (JDH)
Date: June 23, 1986
Creator: Lee, E.P.; Younger, F.C.; Cruz, G.E. & Nolting, E.
System: The UNT Digital Library
Determination of the linear aperture of the SSC (Superconducting Supercollider) clustered lattice used for the conceptual design report (open access)

Determination of the linear aperture of the SSC (Superconducting Supercollider) clustered lattice used for the conceptual design report

A study is made of the linear aperture for the clustered lattice used for the SSC Conceptual Design Report. Random multipole errors are included in all magnetic elements including the insertion dipoles and quadrupoles. Based on the concept of smear, the linear aperture is equal to the dynamic aperture in the range -0.1 less than or equal to ..delta..P/P less than or equal to 0.03%. Strong coupling for ..delta..P/P > 0% produces large smears. A variation of the smear parameter that is insensitive to coupling is proposed. A comparison is made with results reported in the SSC Conceptual Design Report.
Date: June 23, 1986
Creator: Dell, G.F.
System: The UNT Digital Library
Loading capacity of various filters for lithium fire generated aerosols (open access)

Loading capacity of various filters for lithium fire generated aerosols

The lithium aerosol loading capacity of a prefilter, HEPA filters and a sand and gravel bed filter was determined. The test aerosol was characterized and was generated by burning lithium in an unlimited air atmosphere. Correlation to sodium aerosol loading capacities were made to relate existing data to lithium aerosol loadings under varying conditions. This work is being conducted in support of the fusion reactor safety program. The lithium aerosol was generated by burning lithium pools, up to 45 kgs, in a 340 m/sup 3/ low humidity air atmosphere to supply aerosol to recirculating filter test loops. The aerosol was sampled to determine particle size, mass concentrations and chemical species. The dew point and gas concentrations were monitored throughout the tests. Loop inlet aerosol mass concentrations ranged up to 5 gr/m/sup 3/. Chemical compounds analyzed to be present in the aerosol include Li/sub 2/O, LiOH, and Li/sub 2/CO/sub 3/. HEPA filters with and without separators and a prefilter and HEPA filter in series were loaded with 7.8 to 11.1 kg/m/sup 2/ of aerosol at a flow rate of 1.31 m/sec and 5 kPa pressure drop. The HEPA filter loading capacity was determined to be greater at a lower flow rate. …
Date: October 23, 1980
Creator: Jeppson, D.W. & Barreca, J.R.
System: The UNT Digital Library
Design of the plasma current sensor diagnostic for MFTF-B (open access)

Design of the plasma current sensor diagnostic for MFTF-B

The Plasma Current Sensor (PCS) diagnostic includes large diamagnetic loops (DL) that fully encircle the plasma as well as small multi-turn pickup coils (PCs) located between the plasma and the superconducting magnets. Both types of sensors respond to changing magnetic flux linkages caused by plasma currents and are used to measure plasma diamagnetism, from which estimates of temperature and density can be made. The DLs are used in the central cell and Axicell regions, while the PCs are used in the Yin-yang regions where DLs are impractical. Other PCs are used in the central cell to detect axial plasma currents, to help tune trim coils in the transition cell and confirm theoretical estimates of radial diffusion limits. This paper describes the PCS diagnostic and presents the detailed mechanical and electrical designs.
Date: November 23, 1983
Creator: Goerz, D. A.; House, P. A. & Wells, C. W.
System: The UNT Digital Library
GRPANL: a program for deconvoluting and interpreting complex peak clusters (open access)

GRPANL: a program for deconvoluting and interpreting complex peak clusters

GRPANL (GRouP ANaLysis) is a general-purpose peak fitting program that first determines gamma-ray and x-ray energies and intensities for specified peaks or clusters of peaks in a spectrum and then proceeds to interpret these results, determining both the radioisotopes detected and the amounts of each in the sample. Versions of the program are now running on the Digital Equipment Corporation (DEC) VAX and PDP-11 computers. The code has several unique capabilities for deconvoluting and interpreting difficult analytical situations that other codes usually cannot handle.
Date: March 23, 1984
Creator: Gunnink, R.; Ruhter, W. D. & Niday, J. B.
System: The UNT Digital Library
The Oak Ridge National Laboratory's Robotics and Intelligent Systems Program (open access)

The Oak Ridge National Laboratory's Robotics and Intelligent Systems Program

The goals of the newly formed Robotics and Intelligent Systems Program are discussed. The application of the remote systems technology developed by the Consolidated Fuel Reprocessing Program for the Department of Energy is presented. The activities (satellite refueling and space station truss assembly) with the National Aeronautics and Space Administration are presented in a videotape format with narration by the presenter. The goals of technology transfer to the private sector and the potential positive impact on the community conclude the oral presentation.
Date: January 23, 1987
Creator: Meacham, S. A.
System: The UNT Digital Library
Overview of the ICF 1000 MJ experiment chamber design (open access)

Overview of the ICF 1000 MJ experiment chamber design

A conceptual design of an experiment chamber for a high gain ICF facility (1000 MJ) is being developed. Performance goals have been established. Several design approaches are being evaluated through computer simulation, engineering analysis, and experimental testing of candidate first wall components. 10 refs., 3 figs.
Date: September 23, 1988
Creator: Slaughter, D.
System: The UNT Digital Library
Progress in Diamond Cell Experiments: Pressures Above Three Megabars (open access)

Progress in Diamond Cell Experiments: Pressures Above Three Megabars

Diamond cell experiments at pressures above 2 megabars have many important applications with respect to planetary interiors (e.g., metallization of hydrogen). To make possible acquisition of data at extreme pressures on materials of planetary interest, we have been exploring both numerically and experimentally several aspects of diamond cell design and methodology. We have conducted detailed finite element analyses of the diamond cell to explore how bevelled anvils and material properties of the gasket affect diamond cell performance (1). These calculations include nonlinear equations of state, gasket plasticity, and diamond-gasket interfacial friction. Gasket plasticity has a dramatic effect on the stress field and thus must be included in any physically realistic analysis of the diamond cell; purely elastic calculations, therefore, cannot model adequately the behavior of a diamond cell. Gasket yield strengh is very important in facilitating generation of extreme pressures in a diamond cell. Increasing gasket yield strength allows a higher radial pressure gradient to be supported at a given gasket thickness, which means that failure of an experiment by deformation of the anvils to allow anvil-anvil contact occurs at higher pressures than would occur with a lower yield strength gasket. Furthermore, the finite element analyses indicate that increasing gasket …
Date: January 23, 1986
Creator: Goettel, K. A.; Reichlin, R.; Moss, W. C. & Martin, S.
System: The UNT Digital Library