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Beauty physics at Fermilab fixed target energies
The very high luminosities (>>10/sup 32/cm/sup /minus/2/sec/sup /minus/1/) available in the Fermilab fixed target experimental areas offer immediate opportunities for producing large samples (>10/sup 8/ of B hadrons in individual experiments. The possibilities of accumulating large samples of B decays are limited by experimental techniques and trigger strategies and not by available luminosity. At the present time one experiment, E771, is approved to begin B physics experimentation and several other experimental possibilities are being discussed. Some of the problems and the potential of B experiments at fixed target energies as B factories are discussed.
Date:
April 1, 1988
Creator:
Cox, B.
Object Type:
Report
System:
The UNT Digital Library
Electron-positron physics at 1 TeV
We discuss the motivation for TeV e/sup +/ e/sup )minus/) linear colliders, some aspects of their design, and the experimental consequences that follow from the design. After a brief discussion of the general physics environment, we consider the discovery potential of these colliders by examining three sample processes: the detection of new heavy leptons, standard Higgs bosons, and charged Higgs bosons. 13 refs., 22 figs., 5 tabs.
Date:
March 1, 1988
Creator:
Feldman, G. J.
Object Type:
Article
System:
The UNT Digital Library
Root cause analysis at the Savannah River Plant
Events (or near misses) provide important information about ways to improve plant performance. Any particular event may have several /open quotes/root causes/close quotes/ that need correcting to prevent recurrence of the event and, thereby, improve the safety of the plant. Also, by reviewing a large number of events, one can identify cause trends or /open quotes/generic concerns./close quotes/ A method has been developed at Savannah River Plant (SRP) to systematically evaluate events, identify their root causes, record the root causes, and analyze the root cause trends. By providing a systematic method to identify correctable root causes, the system helps the event investigator ask the right questions during the investigation. It also provides an independent safety analysis group and management with statistics indicating existing and developing trouble spots. 3 refs., 4 figs.
Date:
January 1, 1988
Creator:
Paradies, M & Busch, D
Object Type:
Article
System:
The UNT Digital Library
A proposal for a precision test of the standard model by neutrino-electron scattering (Large /hacek C/erenkov Detector Project)
A precision measurement of neutrino-electron elastic scattering from a beam stop neutrino source at LAMPF is proposed. The total error in sin/sup 2/theta/sub W/ is estimated to be +-0.89/percent/. The experiment also will be sensitive to neutrino oscillations and supernova-neutrino bursts, and should set improved limits on the neutrino-charge radius and magnetic-dipole moment. The detector consists of a 2.5-million-gallon tank of water with approximately 14,000 photomultiplier tubes lining the surfaces of the tank. Neutrino-electron scattering events will be observed from the /hacek C/erenkov radiation emitted by the electrons in the water. 19 refs.
Date:
April 1, 1988
Creator:
Allen, R. C.; Lu, X.-Q.; Gollwitzer, K.; Igo, G. J.; Gulmez, E.; Whitten, C. et al.
Object Type:
Report
System:
The UNT Digital Library
Sperm-head morphology study in B6C3F1 mice following inhalation exposure to 1,3-butadiene: Final technical report
The present report describes the results of a study of the morphology of epididymal sperm heads of B6C3F1 mice that were exposed to varying concentrations of 1,3-butadiene. During the fifth post-exposure week, the animals were killed and examined for gross lesions of the reproductive tract; suspensions of the epididymal sperm were prepared for morphologic evaluations. No mortality was observed in any of the inhalation exposure groups. Transient toxic signs, including piloerection and dyspnea, were evident during a 20- to 30-minute period following exposure to 5000 ppM. Mean values for body weights and weight gains of the mice exposed to 1,3-butadiene were not significantly different from control values. A concentration-related increase in the incidence of sperm-head abnormalities was evident and the percentage of sperm heads that were morphologically abnormal was significantly higher in mice exposed to 1000 and 5000 ppM than in the controls. 23 refs., 2 figs., 6 tabs.
Date:
April 1, 1988
Creator:
Hackett, P. L.; McClanahan, B. J.; Brown, M. G.; Buschbom, R. L.; Clark, M. L.; Decker, J. R. et al.
Object Type:
Report
System:
The UNT Digital Library
A subregion block iteration to 3-D finite element modeling of subsurface flow
A subregion block iteration (SBI) technique has been developed in conjunction with finite element approximations of saturated-unsaturated flow equations. The proposed SBI technique is implemented in a three-dimensional finite element saturated-unsaturated flow model. The model is verified with a nonlinear diffusion equation having an analytical solution. It is then applied to a burial trench problem. It is not possible to solve this field problem using the direct elimination finite element method. The SBI technique provides significant improvement over models based on direct band solution methods in both central processing unit (CPU) storage and CPU time. 5 refs., 2 figs.
Date:
January 1, 1988
Creator:
Yeh, G.T.
Object Type:
Article
System:
The UNT Digital Library
Development of biomass gasification to produce substitute fuels
The development of an efficient pressurized, medium-Btu steam-oxygen-blown fluidized-bed biomass gasification process was conducted. The overall program included initial stages of design-support research before the 12-ton-per-day (TPD) process research unit (PRU) was built. These stages involved the characterization of test-specific biomass species and the characteristics and limits of fluidization control. Also obtained for the design of the adiabatic PRU was information from studies with bench-scale equipment on the rapid rates of biomass devolatilization and on kinetics of the rate-controlling step of biomass char and steam gasification. The development program culminated with the sucessful operation of the PRU through 19 parametric-variation tests and extended steady-state process-proving tests. the program investigated the effect of gasifier temperature, pressure, biomass throughput rate, steam-to-biomass ratio, type of feedstock, feedstock moisture, and fludized-bed height on gasification performance. A long-duration gasification test of 3 days steady-state operation was conducted with the whole tree chips to indentify long-term effects of fluidized process conditions; to establish gasifier material and energy balances; to determine the possible breakthrough of low concentration organic species; and to evaluate the mechanical performance of the system components. Results indicate that the pressurized fludizied-bed process, can achieve carbon conversions of about 95% with cold gas thermal …
Date:
March 1, 1988
Creator:
Evans, R. J.; Knight, R. A.; Onischak, M. & Babu, S. P.
Object Type:
Report
System:
The UNT Digital Library
Microscopy and Elemental Analysis in Tissue Samples Using Computed Microtomography With Synchrotron X-Rays
The initial development shows that CMT using synchrotron x-rays can be developed to ..mu..m spatial resolution and perhaps even better. This creates a new microscopy technique which is of special interest in morphological studies of tissues, since no chemical preparation or slicing of the sample is necessary. The combination of CMT with spatial resolution in the ..mu..m range and elemental mapping with sensitivity in the ppM range results in a new tool for elemental mapping at the cellular level. 7 refs., 1 fig.
Date:
January 1, 1988
Creator:
Spanne, P. & Rivers, M. L.
Object Type:
Article
System:
The UNT Digital Library
Costs of nuclear waste glassmaking at Savannah River
Recently developed reference schedules for processing high-level nuclear wastes into solid glass froms at Savannah River provide bases for economic evaluations of potential improvements of glass melter design and operation. Greater melter output is achieved through increases in capacity and attainment and possible higher glass waste loadings. The economic evaluation indicates only minor beneficial impacts on total waste disposal costs for melter outputs greater than current reference values. In contrast, cost impacts are detrimentally large for outputs less than reference values, providing important incentives for development to ensure the reference output. The limits on cost benefits for greater-than-reference output are not intrinsic to on melter feed specified to control radiation and heat loads of the product glass waste form. 14 ref., 3 figs., 1 tab.
Date:
January 1, 1988
Creator:
McDonell, W R; Thomas, S D & Goodlett, C B
Object Type:
Article
System:
The UNT Digital Library
Some fundamental aspects of the optical potential for the interaction of fast neutrons with cobalt
Differential elastic- and inelastic-scattering cross sections, measured from approx.1.5 to 10.0 MeV, are interpreted in terms of spherical-optical-statistical (OM) and coupled-channels models. A successful description of the differential elastic scattering below 10 MeV and the total cross section to 20.0 MeV is achieved using the spherical OM with energy-dependent strengths and geometries. These energy dependencies are large below approx.7.0 MeV, but become smaller and similar to those reported for /open quotes/global/close quotes/ potentials at higher energies. This change in the energy dependence of the parameters probably marks the onset of the Fermi surface anomaly approx.19 MeV above the Fermi energy. Inelastic scattering to the levels below 1.8 MeV displays a forward-peaked behavior. This nonstatistical component is interpreted using the weak-coupling model in which the f/sub 7/2 proton hole is coupled to the 2/sup /plus// state in /sup 60/Ni. This model provides an explanation of the unusual energy dependence and relatively small radius found for the imaginary OM potential. The coupling also contributes to the large value of this potential. The real spherical OM potential derived from the neutron-scattering results is extrapolated to bound energies by using the dispersion relationship and the method of moments. The resulting real-potential strength and radius …
Date:
January 1, 1988
Creator:
Smith, A. B. & Lawson, R. D.
Object Type:
Article
System:
The UNT Digital Library
Considerations for the use of synchrotron radiation sources to measure sub-keV x-ray photoabsorption cross sections in transmission
Sub-keV x-ray photoabsorption cross section measurements in transmission have been made using synchrotron radiation beam lines on the VUV storage ring at the National Synchrotron Light Source (NSLS) and on the SPEAR storage ring at Stanford. The experimental considerations associated with making absolute measurements are reviewed, along with techniques for resolving difficulties. Suggestions for future measurements are included.
Date:
February 1, 1988
Creator:
Tirsell, K.G. & Del Grande, N.K.
Object Type:
Article
System:
The UNT Digital Library
High-fidelity in isotope ratio measurements for resonance ionization mass spectrometry
Calculations are performed to gauge the effect of the convolution of atomic spectral characteristics with laser sources upon isotope ratio measurements by Resonance Ionization Mass Spectrometry (RIMS). Comparison with experimental data is included. 7 refs., 3 figs.
Date:
January 1, 1988
Creator:
Miller, C. M.; Fearey, B. L.; Palmer, B. A. & Nogar, N. S.
Object Type:
Article
System:
The UNT Digital Library
A toxicological study of gadolinium nitrate
The sensitization study in the guinea pig did not show gadolinium nitrate to have potential sensitizing properties. Skin application studies in the rabbit demonstrated that it was cutaneously a severe irritant. This material was considered an irritant in the rabbit eye application studies. 3 refs., 1 tab.
Date:
May 1, 1988
Creator:
London, J.E.
Object Type:
Report
System:
The UNT Digital Library
Introduction to human factors
Some background is given on the field of human factors. The nature of problems with current human/computer interfaces is discussed, some costs are identified, ideal attributes of graceful system interfaces are outlined, and some reasons are indicated why it's not easy to fix the problems. (LEW)
Date:
March 1, 1988
Creator:
Winters, J. M.
Object Type:
Article
System:
The UNT Digital Library
Milliwatt generator project: Progress report, April 1983--March 1984
This report covers progress on the Milliwatt Generator Project during April 1983--March 1984. Activities included (plutonium 238 oxide) fuel processing and characterization, production of heat sources, fabrication of pressure-burst test units, compatibility studies, impact testing, examination of surveillance units, Inconel weld development, and qualilty assurance.
Date:
May 1, 1988
Creator:
Rinehart, G.H. & Latimer, T.W.
Object Type:
Report
System:
The UNT Digital Library
Remote reactor repair: GTA (gas tungsten Arc) weld cracking caused by entrapped helium
A repair patch was welded to the wall of a nuclear reactor tank using remotely controlled thirty-foot long robot arms. Further repair was halted when gas tungsten arc (GTA) welds joining type 304L stainless steel patches to the 304 stainless steel wall developed toe cracks in the heat-affected zone (HAZ). The role of helium in cracking was investigated using material with entrapped helium from tritium decay. As a result of this investigation, and of an extensive array of diagnostic tests performed on reactor tank wall material, helium embrittlement was shown to be the cause of the toe cracks.
Date:
January 1, 1988
Creator:
Kanne, W. R., Jr.
Object Type:
Article
System:
The UNT Digital Library
Accelerator and Fusion Research Division: 1987 summary of activities
An overview of the design and the initial studies for the Advanced Light Source is given. The research efforts for the Center for X-Ray Optics include x-ray imaging, multilayer mirror technology, x-ray sources and detectors, spectroscopy and scattering, and synchrotron radiation projects. The Accelerator Operations highlights include the research by users in nuclear physics, biology and medicine. The upgrade of the Bevalac is also discussed. The High Energy Physics Technology review includes the development of superconducting magnets and superconducting cables. A review of the Heavy-Ion Fusion Accelerator Research is also presented. The Magnetic Fusion Energy research included the development of ion sources, accelerators for negative ions, diagnostics, and theoretical plasma physics. (WRF)
Date:
April 1, 1988
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Electron irradiation effects in YBa/sub 2/Cu/sub 3/O/sub 7-delta/ single crystals
Defect structures in YBa/sub 2/Cu/sub 3/O/sub 7/minus/delta/ produced by electron irradiation at 300/degree/K, were investigated by transmission electron microscopy. Threshold energies for the production of visible defects were determined to b 152 keV and 131 keV (+- 7 keV) in directions near the a- and b-axes, respectively (b > a, both perpendicular to c, the long axis in the orthorhombic structure). During above-threshold irradiations in an electron flux of 3 x 10 /sup 18/ cm/sup /minus/2/s/sup /minus/1/, extended defects were observed to form and grow to sizes of 10--50 nm over 15 minutes, in material thicknesses varying between 20 and 200 nm. Upon irradiation between the a- and b-thresholds, movement of twin plane boundaries and shrinkage of twinned volume were observed. All these findings suggest oxygen atom displacements in the basal plane with recoil energies near 20 eV. Above-threshold irradiations also show the collapse of c-axis long-range order into a planar faulted defect structure with short range order peaks at 1.2 c and 1.07 c, depending on the irradiation direction. 9 refs., 4 figs.
Date:
April 1, 1988
Creator:
Kirk, M.A.; Baker, M.C.; Liu, J.Z.; Lam, D.J. & Weber, H.W.
Object Type:
Article
System:
The UNT Digital Library
Incinerator ash dissolution model for the system: Plutonium, nitric acid and hydrofluoric acid
This research accomplished two goals. The first was to develop a computer program to simulate a cascade dissolver system. This program would be used to predict the bulk rate of dissolution in incinerator ash. The other goal was to verify the model in a single-stage dissolver system using Dy/sub 2/O/sub 3/. PuO/sub 2/ (and all of the species in the incinerator ash) was assumed to exist as spherical particles. A model was used to calculate the bulk rate of plutonium oxide dissolution using fluoride as a catalyst. Once the bulk rate of PuO/sub 2/ dissolution and the dissolution rate of all soluble species were calculated, mass and energy balances were written. A computer program simulating the cascade dissolver system was then developed. Tests were conducted on a single-stage dissolver. A simulated incinerator ash mixture was made and added to the dissolver. CaF/sub 2/ was added to the mixture as a catalyst. A 9M HNO/sub 3/ solution was pumped into the dissolver system. Samples of the dissolver effluent were analyzed for dissolved and F concentrations. The computer program proved satisfactory in predicting the F concentrations in the dissolver effluent. The experimental sparge air flow rate was predicted to within 5.5%. The …
Date:
June 1, 1988
Creator:
Brown, E V
Object Type:
Report
System:
The UNT Digital Library
(Pulsed atmospheric fluidized-bed combustion). [Installation of the pulsed atmospheric fluidized-bed combustion components]
This second Quarterly Technical Progress Report presents the results of work accomplished during the period July 25 through October 30, 1988. The overall objective of the program is the development of a pulsed atmospheric fluidized-bed combustion (PAFBC) technology to burn coal and to provide heat and steam to commercial, institutional, and small industrial applications at a reasonable price in environmentally acceptable manner. Progress during this period accelerated rapidly. The site for the installation of the PAFBC was completed. All of the system components, including the fabrication of the furnace, were also completed. Additional component testing and inspection was also completed. By the end of this period the AFBC was completely assembled and installed at the site adjacent to the MTCI facility and shakedown tests were initiated. 20 figs., 2 tabs.
Date:
October 1, 1988
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Static magnetic ordering of CeCu/sub 2. 1/Si/sub 2/ found by muon spin relaxation
Zero- and longitudinal-field muon spin relaxation measurements on a poly-crystal sample of a heavy-fermion superconductor CeCu/sub 2.1/Si/sub 2/ (T/sub c/ = 0.7 K) have revealed an onset of static magnetic ordering below T )approximately) 0.8 K. The line shapes of the observed spectra in zero field indicate a wide distribution of static random local fields at muon sites, suggesting that the ordering is either spin glass or incommensurate spin-density-wave state. The observed width of the random local field at T = 0.05 K corresponds to a small averaged static moment of the order of 0.1 ..mu../sub B/ per formula unit.
Date:
January 1, 1988
Creator:
Uemura, Y. J.; Kossler, W. J.; Yu, X. H.; Schone, H. E.; Kempton, J. R.; Stronach, C. E. et al.
Object Type:
Article
System:
The UNT Digital Library
Prediction of the migration of radionuclides to the boundary of a shallow land burial trench
A general model which predicts the source term, radionuclide release rate, as a function of water flow, container degradation rate, waste form leach rate, and radionuclide migration rate from a low-level waste shallow land burial treach is being developed. This paper discusses modeling radionuclide migration, one component of the source term. Simulations of radionuclide transport from a generic shallow land burial trench have been performed for a range of water flow rates, dispersivity values, and distribution coefficients. For the modeling assumptions used and the range of parameters tested, the water flow rate plays the major role in redistributing radionuclides within the trench, except in the case of extremely high dispersion. Dispersion was always found to play significant role in determining transport. This was particularly apparent upstream from the source. Sorption decreased the magnitude of the radionuclide concentration and had the apparent effect of reducing the velocity with which the radionuclides were transported. Diffusion was found to be unimportant in determining radionuclide transport. 12 refs., 8 figs., 2 tabs.
Date:
January 1, 1988
Creator:
Sullivan, T.M.
Object Type:
Article
System:
The UNT Digital Library
Evaluation of station blackout accidents at nuclear power plants: Technical findings related to unresolved safety issue A-44: Final report
''Station Blackout,'' which is the complete loss of alternating current (AC) electrical power in a nuclear power plant, has been designated as Unresolved Safety Issue A-44. Because many safety systems required for reactor core decay heat removal and containment heat removal depend on AC power, the consequences of a station blackout could be severe. This report documents the findings of technical studies performed as part of the program to resolve this issue. The important factors analyzed include: the fequency of loss of offsite power; the probability that emergency or onsite AC power supplies would be unavailable; the capability and reliability of decay heat removal systems independent of AC power; and the likelihood that offsite power would be restored before systems that cannot operate for extended periods without AC power fail, thus resulting in core damage. This report also addresses effects of different designs, locations, and operational features on the estimated frequency of core damage resulting from station blackout events.
Date:
June 1, 1988
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
A study of low Q/sup 2/ radiative Bhabha scattering
This thesis presents a study of electron-positron scattering, via nearly real photon exchange, where in the process one or more high energy photons are produced. The motivations behind the work are twofold. Firstly, the study is a sensitive test of the theory of electron-photon interactions, quantum electrodynamics. A deviation from the theory could indicate that the electron is a composite particle. Secondly, a thorough understanding of this process is necessary for experiments to be done in the near future at the Stanford Linear Collider and the LEP facility at CERN. Calculations for the process to third and fourth order in pertubation theory are described. Methods for simulating the process by a Monte Carlo event generator are given. Results from the calculations are compared to data from the Mark II experiment at the PEP storage ring. The ratio of measured to calculated cross sections are 0.993 /+-/ 0.017 /+-/ 0.015 and 0.99 /+-/ 0.16 /+-/ 0.08 for final states with one and two observed photons respectively, where the first errors are statistical and the second systematic. The excellent agreement verifies the calculations of the fourth order radiative correction. No evidence for electron substructure is observed.
Date:
March 1, 1988
Creator:
Karlen, D.A.
Object Type:
Report
System:
The UNT Digital Library