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Search for narrow states produced in the reaction. pi. /sup -/p. -->. n +. gamma. 's at 13 GeV/c

Description: A double arm lead-glass lead-scintillator calorimeter system was used to search for narrow states, such as the eta/sub c/, produced in the exclusive reactions ..pi../sup -/p ..-->.. ..gamma gamma..n, ..pi../sup -/p ..-->.. ..pi../sup 0/..gamma..n, and ..pi../sup -/p ..-->.. ..pi../sup 0/..pi../sup 0/n at 13 GeV/c. A 90% c.l. upper limit sigma.BR < 260 pb was found for ..gamma gamma.. states with masses from 2.6 to 3.1 GeV/c/sup 2/. Corresponding limits on narrow ..pi../sup 0/..gamma… more
Date: July 7, 1980
Creator: Chiang, I. H.; Johnson, R. A. & Kwan, B.
Partner: UNT Libraries Government Documents Department
open access

MTX (Microwave Tokamak Experiment) facility and machine grounding plan

Description: A key issue in the design of fusion research experiments and their related facilities is the control of ground currents. Because of the large magnetic field, high voltages and high currents present in most of these installations, it is essential to avoid ground loops, and to control ground currents during both normal operations and fault conditions. This paper describes the grounding policy that was developed for MTX. The vault area was divided into zones, and each of the four walls was treated… more
Date: October 7, 1987
Creator: Bell, H.H.; Rice, B.W.; Petersen, D.E. & Herrera, C.H.
Partner: UNT Libraries Government Documents Department
open access

MFTF-B quasi-optical ECRH transmission system

Description: The microwave transmission system for ERCH on MFTF-B will utilize quasi-optical transmission techniques. The system consists of ten gyrotron oscillators: two gyrotrons at 28 GHz, two at 35 GHz, and six at 56 GHz. The 28 and 35 GHz gyrotrons both heat the electrons in the end plug (potential peak) while the 56 GHz sources heat the minimum-B anchor region (potential minimum). Microwaves are launched into a pair of cylindrical mirrors that form a pseudo-cavity which directs the microwaves through … more
Date: November 7, 1983
Creator: Yugo, J. J.; Shearer, J. W. & Ziolkowski, R. W.
Partner: UNT Libraries Government Documents Department
open access

Superconducting (radiation hardened) magnets for mirror fusion devices

Description: Superconducting magnets for mirror fusion have evolved considerably since the Baseball II magnet in 1970. Recently, the Mirror Fusion Test Facility (MFTF-B) yin-yang has been tested to a full field of 7.7 T with radial dimensions representative of a full scale reactor. Now the emphasis has turned to the manufacture of very high field solenoids (choke coils) that are placed between the tandem mirror central cell and the yin-yang anchor-plug set. For MFTF-B the choke coil field reaches 12 T, whil… more
Date: December 7, 1983
Creator: Henning, C. D.; Dalder, E. N. C.; Miller, J. R. & Perkins, J. R.
Partner: UNT Libraries Government Documents Department
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Estimating and coping with public response to radioactive waste repository siting

Description: The siting and construction of a radioactive waste disposal operation is likely to be controversial in the communities being considered, and at the state and national levels as well. Public response can be conceptualized at two levels: individual, and group or organizational. At the individual level, public response is the behavior of people motivated by their attitudes, knowledge, and perceptions of radioactive waste and its hazards and risks. On the group or organizational level, public respo… more
Date: February 7, 1984
Creator: Payne, B.A.
Partner: UNT Libraries Government Documents Department
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Spatial averaging algorithms for ultrasonic inspection of austenitic stainless steel welds

Description: Interpretation of ultrasonic inspection data from stainless steel welds is difficult because the signal-to-noise ratio is very low. The three main reasons for this are the granular structure of the weld, the high attenuation of stainless steel, and electronic noise. Averaging in time at the same position in space reduces electronic noise, but does not reduce ultrasonic noise from grain boundary scattering. Averaging wave-forms from different spatial positions helps reduce grain noise, but desir… more
Date: April 7, 1980
Creator: Horn, J. E.; Cooper, C.S. & Michaels, T.E.
Partner: UNT Libraries Government Documents Department
open access

Magnet power system for the Microwave Tokamak Experiment (MTX)

Description: The system configuration, layout, and general philosophy for the MTX magnet power system is described. The vast majority of the magnet power equipment was quite successfully used on the ALCATOR-C experiment at the Massachusetts Institute of Technology. The AC power for the magnet system at MIT was obtained from a 225MVA alternator. The power for the system at LLNL is obtained directly from the local utility's 230 kV line. This installation, therefore, necessitates the addition of a great deal o… more
Date: October 7, 1987
Creator: Jackson, M.C. & Musslewhite, R.C.
Partner: UNT Libraries Government Documents Department
open access

Thin-thick quadrature frequency conversion

Description: The quadrature conversion scheme is a method of generating the second harmonic. The scheme, which uses two crystals in series, has several advantages over single-crystal or other two crystal schemes. The most important is that it is capable of high conversion efficiency over a large dynamic range of drive intensity and detuning angle.
Date: February 7, 1985
Creator: Eimerl, D.
Partner: UNT Libraries Government Documents Department
open access

Difficulties with inferring neutron cross sections from charged-particle reactions

Description: We have investigated problems associated with inferring cross sections for neutron reactions on unstable nuclei in the mass-90 region from charged-particle reactions on nearby stable targets. We conclude that effects due to precompound evaporation, isospin, and multiple reaction paths severely limit the circumstances under which charged-particle studies may be directly and easily converted to neutron cross sections of useful accuracy. 4 refs., 2 figs.
Date: May 7, 1985
Creator: Gardner, D. G. & Gardner, M. A.
Partner: UNT Libraries Government Documents Department
open access

Role of human- and animal-sperm studies in the evaluation of male reproductive hazards

Description: Human sperm tests provide a direct means of assessing chemically induced spermatogenic dysfunction in man. Available tests include sperm count, motility, morphology (seminal cytology), and Y-body analyses. Over 70 different human exposures have been monitored in various groups of exposed men. The majority of exposures studied showed a significant change from control in one or more sperm tests. When carefully controlled, the sperm morphology test is statistically the most sensitive of these huma… more
Date: April 7, 1982
Creator: Wyrobek, A.J.; Gordon, L. & Watchmaker, G.
Partner: UNT Libraries Government Documents Department
open access

Benchmark cross sections for bottom quark production

Description: A summary is presented of theoretical expectations for the total cross sections for bottom quark production, for longitudinal and transverse momentum distributions, and for b, /bar b/ momentum correlations at Fermilab fixed target and collider energies.
Date: January 7, 1988
Creator: Berger, E. L.
Partner: UNT Libraries Government Documents Department
open access

Improvements in the weldability of a superconductor sheath material

Description: This paper investigates the effects of chemistry and heat treatment variation on the 4-K tensile properties of A-286, a candidate sheath material for force-cooled superconductors. Currently, full use of A-286 and similar superalloys is limited by the observed low yield and ultimate tensile strengths in the welded and aged condition. The low strength is shown to be associated with the formation of precipitate-free zones as a result of alloying-element segregation during weld pool solidification.… more
Date: August 7, 1985
Creator: Summers, L.T. & Morris, J.W. Jr.
Partner: UNT Libraries Government Documents Department
open access

Calculational tools for the evaluation of nuclear cross-section and spectra data

Description: A technique based on discrete energy levels rather than energy level densities is presented for nuclear reaction calculations. The validity of the technique is demonstrated via theoretical and experimental agreement for cross sections, isomer-ratios and gamma-ray strength functions. 50 refs., 7 figs. (WRF)
Date: May 7, 1985
Creator: Gardner, M.A.
Partner: UNT Libraries Government Documents Department
open access

Automated supernova search

Description: A program is described for development of an automated supernova search based upon complete remote computer control of a telescope and vidicon digital imaging system. (GHT)
Date: October 7, 1981
Creator: Colgate, S. A.
Partner: UNT Libraries Government Documents Department
open access

High-field superconducting solenoids for the TIBER II PF (poloidal-field) system

Description: The poloidal-field (PF) coil set for the Tokamak Ignition/Burn Engineering Reactor (TIBER-II) consists of 24 solenoid modules, 16 of which are stacked inside the toroidal-field (TF) system at the center of the machine. These central solenoid modules operate at high-current densities, and maximum fields at the windings approach 14 T. Although TIBER-II is designed for steady-state operation with noninductive current drive, other operating scenarios are also considered. In the pulsed or inductive … more
Date: October 7, 1987
Creator: Kerns, J. A.; Miller, J. R. & Summers, L. T.
Partner: UNT Libraries Government Documents Department
open access

TIBER-II TF (toroidal-field) winding pack design

Description: The superconducting, toroidal-field (TF) coils in the Tokamak Ignition/Burn Engineering Reactor (TIBER II) are designed with cable-in-conduit conductor (CICC) using Nb/sub 3/Sn composite strands. To design the CICC winding pack, we used an optimization technique that maximizes the conductor stability without violating the constraints imposed by the structure, electrical insulation, quench protection, and fabrication technique. Detailed helium-properties codes calculate the heat removal along a … more
Date: October 7, 1987
Creator: Kerns, J. A.; Miller, J. R.; Slack, D. S. & Summers, L. T.
Partner: UNT Libraries Government Documents Department
open access

Creep of 304 LN and 316 L stainless steels at cryogenic temperatures

Description: Creep behavior of Type 304 LN plate and 316 L shielded-metal-arc (SMA)-deposited stainless weld metal was investigated at 4/sup 0/K. Testing was performed at constant load in a creep machine with a cryostat designed for long-term stability. Both transient and steady-state creep were observed during tests lasting over 2000 hours. Steady-state creep rates were much greater than expected from extrapolations of 300-K creep data. Creep rates on the order of 10/sup -10/ s/sup -1/ were observed at str… more
Date: August 7, 1985
Creator: Roth, L. D.; Manhardt, A. E.; Dalder, E. N. C. & Kershaw, R. P., Jr.
Partner: UNT Libraries Government Documents Department
open access

New harmonic materials: index engineering. Thin-thick quadrature frequency conversion

Description: The quadrature conversion scheme is a method of generating the second harmonic. The scheme, which uses two crystals in series, has several advantages over single-crystal or other two crystal schemes. The most important is that it is capable of high conversion efficiency over a large dynamic range of drive intensity and detuning angle. Consider a pair of KDP crystals cut for type-II phase matching. In the quadrature scheme, the optic axes of the crystals are arranged so that the plans containing… more
Date: February 7, 1985
Creator: Eimerl, D.
Partner: UNT Libraries Government Documents Department
open access

Proceedings of the 1986 summer workshop on antiproton beams in the 2-10 GeV/c range

Description: The possibilities for building a facility for the formation spectroscopy of ''charmonium'' and the study of ''exotics'' at the AGS with high intensity antiproton beams of good resolution and enhanced purity are explored. The performance potential of a number of long beams and the AGS booster are evaluated and costs are estimated. Fluxes of several 10/sup 7/ antiprotons per pulse with purities of 5% to 99% are possible with conventional long beams. A similar total antiproton flux would be availa… more
Date: May 7, 1987
Creator: Lazarus, D. (ed.)
Partner: UNT Libraries Government Documents Department
open access

Materials at extreme conditions: ICF targets

Description: Currently two simple theories are heavily used in laser-fusion research: the Thomas-Fermi-Dirac statistical model, and an atomic ionization model based on screened hydrogen like energy levels. Recent improvements in these theories are summarized. We show representation calculations of thermodynamic properties, ionization, x-ray emission rates and fast-ion stopping powers, and give a brief sketch of the major unresolved scientific questions.
Date: April 7, 1980
Creator: More, R.M.
Partner: UNT Libraries Government Documents Department
open access

Inversion approach for thermal data from a convecting hydrothermal system. Revision 1

Description: Hydrothermal systems are often studied by collecting thermal gradient data and temperature-depth curves. These data contain important information about the flow field, the evolution of the hydrothermal system, and the location and nature of the ultimate heat sources. Thermal data are conventionally interpreted by the ''forward'' method; the thermal field is calculated based on selected initial conditions and boundary conditions such as temperature and permeability distributions. If the calculat… more
Date: June 7, 1985
Creator: Kasameyer, P.; Younker, L. & Hanson, J.
Partner: UNT Libraries Government Documents Department
open access

Cable-in-conduit conductor optimization for fusion magnet applications

Description: Careful design of the toroidal-field (TF) and poloidal-field (PF) coils in a tokamak machine using cable-in-conduit conductors (CICC) can result in quite high overall winding-pack current densities - even with the high nuclear heat loads that may be imposed in operating a fusion reactor - and thereby help reduce the overall machine size. In our design process, we systematically examined the operational environment of a magnet, e.g., mechanical stresses, current, field, heat load, coolant temper… more
Date: October 7, 1987
Creator: Miller, J. R. & Kerns, J. A.
Partner: UNT Libraries Government Documents Department
open access

Pulse-power circuit diagnostics for the Nova laser

Description: The Nova laser will have a large pulse power system for driving laser amplifiers, incorporating approximately 1600 flashlamp circuits. An automated system has been designed for diagnosing the condition of these flashlamp circuits. It records digitized circuit current waveforms and detects current excursions above a given threshold. In addition, it is able to fire flashlamps at a low energy to ascertain the health of the system. Data from this system can be ploted for inspection by the operator,… more
Date: June 7, 1982
Creator: Christie, D. J.; Dallum, G. E.; Gritton, D. G.; Merritt, B. T.; Whitham, K. & Berkbigler, L. W.
Partner: UNT Libraries Government Documents Department
open access

Molecular-dynamics calculations of energetic displacement cascades

Description: The results of fully dynamic computer simulations of collision cascades show an abrupt decrease in defect production efficiency beginning at energies about 10 times the minimum threshold energy in agreement with experimental results on resistivity damage rates at 4.2 K. A detailed analysis of the time development of a typical cascade reveals that this drop in efficiency is primarily due to recombination by defect transport during the cascade cooling phase. This transport is an order of magnitud… more
Date: August 7, 1981
Creator: Guinan, M.W. & Kinney, J.H.
Partner: UNT Libraries Government Documents Department
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