States

Antiprotons and the Crystal Ball (open access)

Antiprotons and the Crystal Ball

During the 1998 running of the Crystal Ball experiment, a couple of brief test runs were done with the C6 beamline tuned to produce antiprotons. Specifically, one shift on July 29th produced runs 329-334 with the beam momentum set for 650 MeV/c, run 355 was done on July 31st with a 550 MeV/c beam momentum, and run 926-929 were obtained in a single shift on November 3rd, also with a beam momentum of 550 MeV/c. The beam tune for the November data was greatly superior to that of the July data, however. Therefore, only the November data have been analyzed in detail, and the results of this analysis are presented in this note. Due to the paucity of statistics that were obtained, it was decided not to attempt to publish the results. However, the results are valuable as a tool for planning a possible future program of dedicated measurements of antiproton-proton annihilation into all-neutral final states using the Crystal Ball. The data in fact show that the Crystal Ball with its large angular acceptance and multi-photon capability would be an excellent detector for such an experiment. Only one other such experiment (the Crystal Barrel experiment at CERN/LEAR) has ever been …
Date: November 15, 1999
Creator: Allgower, C. & Peaslee, D.
Object Type: Report
System: The UNT Digital Library
Hadroproduction of charm at Fermilab E769 (open access)

Hadroproduction of charm at Fermilab E769

Experiment E769 at Fermilab obtained charm hadroproduction data during the 1987-88 Fixed Target running period with a 250 GeV hadron beam incident on thin target foils of Be, Al, Cu, and W. From an analysis of 25% of the recorded 400M trigger sample we have explored the Feynman x, p{sub t}{sup 2} and the atomic number dependence of charm quark production using samples of D{sup +} and D{sup 0} mesons. 7 refs., 4 figs.
Date: November 15, 1990
Creator: Alves, G. A.; Anjos, J. C.; de Mello Neto, J. R. T.; de Miranda, J. M.; da Motta, H.; dos Reis, A. C. et al.
Object Type: Article
System: The UNT Digital Library
Identification and Evaluation of Fluvial-Dominated Deltaic Reservoirs. (open access)

Identification and Evaluation of Fluvial-Dominated Deltaic Reservoirs.

This document is provided as a Quarterly Technical Progress Report for the program entitled `Identification and Evaluation of Fluvial- Dominated Deltaic (Class I Oil) Reservoirs in Oklahoma`, covering the reporting period of July 1 - September 30, 1997. Work is progressing as expected for the project. The Tonkawa Play workshop was completed as scheduled on July 9, 1997 in Norman Oklahoma. It was attended by 101 people of whom about 55 were operators. The Bartlesville workshop is scheduled for October and November 1997, in three different sites including Tulsa, Bartlesville, and Norman, Oklahoma. The FDD computer facility is fully operational. During this quarter, there were 10 industry individuals who used the computer facility. This project is serving an extremely valuable role in the technology transfer activities for the Oklahoma petroleum industry, with very positive industry feedback.
Date: November 15, 1997
Creator: Baken, Mary K. & Andrews, Richard
Object Type: Report
System: The UNT Digital Library
Comparison of Analytical and Experimental Effectiveness of Four-Row Plate-Fin-Tube Heat Exchangers with Water, R-22, and R-410A (open access)

Comparison of Analytical and Experimental Effectiveness of Four-Row Plate-Fin-Tube Heat Exchangers with Water, R-22, and R-410A

The analytical solutions of heat exchanger effectiveness for four-row crcmilow, cross-countertlow and cross-paralleltlow have been derived in the recent study. The main objective of this study is to investigate the etlkct of heat exchawger tlow conllguration on thermal performance with refrigerant mixtures. Difference of heat exchanger effectiveness for all flow arrangements relative to an analytical many-row solution has been analyzed. A comparison of four-row cross cou~ltet-ilow heat exchanger effectiveness between analytical solutions and experimental data with water, R-22, and R-4 10A is presented.
Date: November 15, 1998
Creator: Baxter, V. D.; Chen, T. D. & Conklin, J. C.
Object Type: Article
System: The UNT Digital Library
Treatment tests for ex situ removal of chromate, nitrate, and uranium (VI) from Hanford (100-HR-3) groundwater. Final report (open access)

Treatment tests for ex situ removal of chromate, nitrate, and uranium (VI) from Hanford (100-HR-3) groundwater. Final report

This report describes batch and anion exchange column laboratory-scale studies investigating ex situ methods to remove chromate (chromium [VI]), nitrate (NO{sub 3}), and uranium (present as uranyl (uranium [VI]) carbonato anionic species) from contaminated Hanford Site groundwaters. The technologies investigated include chemical precipitation or coprecipitation to remove chromate and uranium, and anion exchange to remove chromate, uranium, and nitrate. The technologies investigated were specified in the 100-HR-3 Groundwater Treatability Test Plan (DOE-RL 1993). The goal of these tests was to determine the best method to remove selected contaminants to below the concentration of the project performance goals. The raw data and observations made during these tests can be found in the Westinghouse Hanford Company (WHC) laboratory notebooks (Beck 1992, Herting 1993). The method recommended for future study is anion exchange with Dowex 21K resin.
Date: November 15, 1993
Creator: Beck, M. A. & Duncan, J. B.
Object Type: Report
System: The UNT Digital Library
RPM-SIM (Renewable Energy Power System Modular Simulator) user's guide (open access)

RPM-SIM (Renewable Energy Power System Modular Simulator) user's guide

Using the VisSimTM visual environment, researchers developed a modular simulation system to facilitate an application-specific, low-cost study of the system dynamics for wind-diesel hybrid power systems. This manual presents the principal modules of the simulator and, using case studies of a hybrid system, demonstrates some of the benefits that can be gained from understanding the effects of the designer's modifications to these complex dynamic systems.
Date: November 15, 1999
Creator: Bialasiewicz, J.T.; Muljadi, E.; Nix, G.R. & Drouilhet, S.
Object Type: Text
System: The UNT Digital Library
Behavior of actinide ions during sludge washing of alkaline radioactive. (open access)

Behavior of actinide ions during sludge washing of alkaline radioactive.

It is difficult to accurately predict actinide behavior during the alkaline leaching of Hanford's radioactive sludges due to the diverse chemical and radiolytic conditions existing in these wastes. The results of Pu dissolution during experimental washing of sludge simulants from the BiPO{sub 4} Redox, and PUREX processes shows that {le} 2.l% Pu is dissolved during contact with alkaline media, but up to 65.5% Pu may be dissolved in acidic media. The dissolution of Cr, Fe, Nd, and Mn has also been observed, and the results of solid state, radioanalytical, and spectroscopic investigations are detailed.
Date: November 15, 1999
Creator: Bond, A. H.; Nash, K. L.; Gelis, A. V.; Jensen, M. P.; Sullivan, J. C. & Rao, L.
Object Type: Article
System: The UNT Digital Library
Cavity design and beam simulations for the APS rf gun (open access)

Cavity design and beam simulations for the APS rf gun

An earlier note discussed the preliminary design of the 1-1/2 cell RF cavity for the APS RF gun. This note describes the final design, including cavity properties and simulation results from the program rf gun. The basic idea for the new design was that the successful SSRL design could be improved upon by reducing fields that had nonlinear dependence on radius. As discussed previously, this would reduce the emittance and produce tighter momentum and time distributions. In addition, it was desirable to increase the fields in the first half-cell relative to the fields in the second half-cell, in order to allow more rapid initial acceleration, which would reduce the effects of space charge. Both of these goals were accomplished in the new design.
Date: November 15, 1991
Creator: Borland, M.
Object Type: Report
System: The UNT Digital Library
Photoexcited charge pair escape and recombination. Progress report, November 15, 1990--November 14, 1991 (open access)

Photoexcited charge pair escape and recombination. Progress report, November 15, 1990--November 14, 1991

We report photocurrent transients arising from the pulsed laser excitation of the dipolar first excited singlet sate S{sub 1} of trans 4-dimethyl-amino-4{prime}-nitrostilbene (DMANS) in toluene solution. The currents arise from rotational reorientation of DMANS dipoles with respect to the axis of an applied electric field. The method appears to offer a simple and general approach to the measurement of the change in dipole moment upon electronic excitation of a molecule. In another experiment, durene (1,2,4,5-tetramethylbenzene) dissolved in n-hexane was photoionized by 35 psec pulses at 266 nm. Transient absorption at 1064 nm arising chiefly from geminate electrons was detected and used to monitor the recombination of the electron-cation pairs produced by two-photon ionization. An excellent fit to the recombination kinetics was obtained by assuming that the distribution of initial electron-cation separations was of the form r{sup 2}EXP = r{sup 2}/(2L{sup 3})exp({minus}r/L) with a mean radius 3L = 5.7 nm.
Date: November 15, 1991
Creator: Braun, C. L.
Object Type: Report
System: The UNT Digital Library
Photoexcited Charge Pair Escape and Recombination (open access)

Photoexcited Charge Pair Escape and Recombination

We report photocurrent transients arising from the pulsed laser excitation of the dipolar first excited singlet sate S{sub 1} of trans 4-dimethyl-amino-4{prime}-nitrostilbene (DMANS) in toluene solution. The currents arise from rotational reorientation of DMANS dipoles with respect to the axis of an applied electric field. The method appears to offer a simple and general approach to the measurement of the change in dipole moment upon electronic excitation of a molecule. In another experiment, durene (1,2,4,5-tetramethylbenzene) dissolved in n-hexane was photoionized by 35 psec pulses at 266 nm. Transient absorption at 1064 nm arising chiefly from geminate electrons was detected and used to monitor the recombination of the electron-cation pairs produced by two-photon ionization. An excellent fit to the recombination kinetics was obtained by assuming that the distribution of initial electron-cation separations was of the form r{sup 2}EXP = r{sup 2}/(2L{sup 3})exp({minus}r/L) with a mean radius 3L = 5.7 nm.
Date: November 15, 1991
Creator: Braun, Charles L.
Object Type: Report
System: The UNT Digital Library
Pyrochemical processing of Idaho Chemical Processing Plant (ICPP) High Level Waste (HLW) calcine (open access)

Pyrochemical processing of Idaho Chemical Processing Plant (ICPP) High Level Waste (HLW) calcine

Inertial force damping control by micromanipulator modulation is proposed to suppress the vibrations of a micro/macro-manipulator system. The proposed controller, developed using classical control theory, is added to the existing control system. The proposed controller uses real-time measurements of macro-manipulator flexibility to adjust the motion of the micro manipulator to counteract structural vibrations. Experimental studies using an existing micro/macro flexible link manipulator testbed demonstrate the effectiveness of the proposed approach to suppression of vibrations in the macro/micro-manipulator system using micromanipulator-based inertial active damping control.
Date: November 15, 1994
Creator: Bronson, M. C.; Ebbinghaus, B. B.; Riley, D. C.; Nelson, L. & Del Debbio, J.
Object Type: Article
System: The UNT Digital Library
200 Area TEDF interface control document (open access)

200 Area TEDF interface control document

Because the TEDF does not have any treatment or retention capacity, strict control at the generator interface is essential to operate the TEDF in compliance with good engineering practices, Hanford site requirements, and the 216 Discharge Permit. The information in the Interface Control Document (ICD) forms the basis of understanding between all parties involved in the TEDF; DOE, WHC, and the generating facilities. The ICD defines the controlling document hierarchy; LEF, and generator responsibilities; monitoring and sampling requirements; and specifies the TEDF/Generator Interface points.
Date: November 15, 1994
Creator: Brown, M. J. & Hildebrand, R. A.
Object Type: Report
System: The UNT Digital Library
Position paper on gas generation in the Waste Isolation Pilot Plant (open access)

Position paper on gas generation in the Waste Isolation Pilot Plant

Gas generation by transuranic (TRU) waste is a significant issue because gas will, if produced in significant quantities, affect the performance of the Waste Isolation Pilot Plant (WIPP) with respect to Environmental Protection Agency (EPA) regulations for the long-term isolation of radioactive and chemically hazardous waste. If significant gas production occurs, it will also affect, and will be affected by, other processes and parameters in WIPP disposal rooms. The processes that will produce gas in WIPP disposal rooms are corrosion, microbial activity and radiolysis. This position paper describes these processes and the models, assumptions and data used to predict gas generation in WIPP disposal rooms.
Date: November 15, 1994
Creator: Brush, L. H.
Object Type: Article
System: The UNT Digital Library
Numerical modeling of shielding by a wire mesh box (open access)

Numerical modeling of shielding by a wire mesh box

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Date: November 15, 1999
Creator: Burke, G. J. & Steich, D. J.
Object Type: Article
System: The UNT Digital Library
ARTI refrigerant database (open access)

ARTI refrigerant database

The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilitates access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufacturers and those using alternative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.
Date: November 15, 1996
Creator: Calm, J. M.
Object Type: Report
System: The UNT Digital Library
Electronic Effects on Grain Boundary Structure in BCC Metals (open access)

Electronic Effects on Grain Boundary Structure in BCC Metals

The dominant factor in determining the atomic structure of grain boundaries is the crystal structure of the material, e.g. FCC vs. BCC. However, for a given crystal structure, the structure of grain boundaries can be influenced by electronic effects, i.e. by the element comprising the crystal. Understanding and modeling the influence of electronic structure on defect structures is a key ingredient for successful atomistic simulations of materials with more complicated crystal structures than FCC. We have found that grain boundary structure is a critical test for interatomic potentials. To that end, we have fabricated the identical {Sigma}5 (3l0)/[001] symmetric tilt grain boundary in three different BCC metals (Nb, MO, and Ta) by diffusion bonding precisely oriented single crystals. The structure of these boundaries have been determined by high resolution transmission electron microscopy. The boundaries have been found to have different atomic structures. The structures of these boundaries have been modeled with atomistic simulations using interatomic potentials incorporating angularly dependent interactions, such as those developed within Model Generalized Pseudopotential Theory. The differing structures of these boundaries can be understood in terms of the strength of the angular dependence of the interatomic interaction. We report here the results for Ta.
Date: November 15, 1999
Creator: Campbell, G. H.; King, W. E.; Belak, J. A.; Moriarty, J. A. & Foiles, S. M.
Object Type: Article
System: The UNT Digital Library
Imaging sciences workshop (open access)

Imaging sciences workshop

This workshop on the Imaging Sciences sponsored by Lawrence Livermore National Laboratory contains short abstracts/articles submitted by speakers. The topic areas covered include the following: Astronomical Imaging; biomedical imaging; vision/image display; imaging hardware; imaging software; Acoustic/oceanic imaging; microwave/acoustic imaging; computed tomography; physical imaging; imaging algorithms. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.
Date: November 15, 1994
Creator: Candy, J.V.
Object Type: Article
System: The UNT Digital Library
A Correlated Study of the Response of a Satellite to Acoustic Radiation Using Statistical Energy Analysis and Acoustic Test Data (open access)

A Correlated Study of the Response of a Satellite to Acoustic Radiation Using Statistical Energy Analysis and Acoustic Test Data

Aerospace payloads, such as satellites, are subjected to vibroacoustic excitation during launch. Sandia's MTI satellite has recently been certified to this environment using a combination of base input random vibration and reverberant acoustic noise. The initial choices for the acoustic and random vibration test specifications were obtained from the launch vehicle Interface Control Document (ICD). In order to tailor the random vibration levels for the laboratory certification testing, it was necessary to determine whether vibration energy was flowing across the launch vehicle interface from the satellite to the launch vehicle or the other direction. For frequencies below 120 Hz this issue was addressed using response limiting techniques based on results from the Coupled Loads Analysis (CLA). However, since the CLA Finite Element Analysis FEA model was only correlated for frequencies below 120 Hz, Statistical Energy Analysis (SEA) was considered to be a better choice for predicting the direction of the energy flow for frequencies above 120 Hz. The existing SEA model of the launch vehicle had been developed using the VibroAcoustic Payload Environment Prediction System (VAPEPS) computer code [1]. Therefore, the satellite would have to be modeled using VAPEPS as well. As is the case for any computational model, the …
Date: November 15, 1999
Creator: Cap, Jerome S. & Tracey, Brian
Object Type: Article
System: The UNT Digital Library
Electron-atom collision studies using optically state selected beams. Progress report, May 15, 1988--May 14, 1991 (open access)

Electron-atom collision studies using optically state selected beams. Progress report, May 15, 1988--May 14, 1991

This report discusses progress made during the current contract period on the authors research program to study collisions between spin-polarized electrons and spin-polarized atoms. The objective of this work is to stimulate a deeper theoretical understanding of the electron-atom interaction by providing the most complete possible experimental characterization of the colliding system. Through the use of optical state preparation techniques to prepare both the incident electrons and atom in well-defined initial states, the authors are able to extract substantially more information about the scattering process than is available from more conventional measurements of differential scattering cross sections. Their primary interest is to study in detail the role played by spin in electron-atom collisions at low to intermediate energies. The additional information provided by these spin-dependent measurements greatly enhances understanding of both exchange and the spin-orbit interaction in the scattering process. During this three-year period they have made substantial progress in measurements of both elastic and superelastic scattering of spin-polarized electrons from optically pumped sodium. The elastic scattering measurements in particular were made possible by several important improvements to the experimental apparatus.
Date: November 15, 1990
Creator: Celotta, R. J. & Kelley, M. H.
Object Type: Report
System: The UNT Digital Library
Measured Delayed Neutron Spectra from the Fission of U-235 and Np-237 (open access)

Measured Delayed Neutron Spectra from the Fission of U-235 and Np-237

Texas A&M University, in collaboration with Oak Ridge National Laboratory / the Japan Atomic Energy Research Institute, have been actively studying the delayed neutron emission characteristics of the higher actinide isotopes for several years. 1-3 Recently, a proton recoil detector system was designed, built, and characterized for use in measuring delayed neutron energy spectra following neutron induced fission. The system has been used to measure aggregate delayed neutron energy spectra from neutron induced fission of U-235 and Np-237. These spectra have also been compared to that calculated using individual precursor P, values, yields, and spectra from the ENDF/B-VI file. A proton recoil detector array consisting of three LND Model 28305 high- -pressure proton recoil detectors has been constructed at the Texas A&M University Nuclear Science Center. The array was characterized using several neutron and gamma- ray sources to check for efficiency, gamma-ray response, and reliability of the unfolding techniques. Resultant measured proton recoil distributions were unfolded using a modified version of the spectrum unfolding code PSNS (the new code was renamed SAC). SAC used response functions calculated using MCNP 4A. This feature allowed the inclusion of several inches of lead between the detector and the source to decrease the detector's …
Date: November 15, 1998
Creator: Charlton, W. S.; Comfort, C.; Parish, T. A. & Raman, S.
Object Type: Article
System: The UNT Digital Library
The Properties and Weldability of Materials for Fusion Reactor Applications (open access)

The Properties and Weldability of Materials for Fusion Reactor Applications

Low-activation austenitic stainless steels have been suggested for applications within fusion reactors. The use of these nickel-free steels will help to reduce the radioactive waste management problem after service. one requirement for such steels is the ability to obtain sound welds for fabrication purposes. Thus, two austenitic Fe-Cr-Mn alloys were studied to characterize the welded microstructure and mechanical properties. The two steels investigated were a Russian steel (Fe-11.6Cr19.3Mn-0.181C) and an US steel (Fe-12.lCr-19.4Mn-0.24C). Welding was performed using a gas tungsten arc welding (GTAW) process. Microscopic examinations of the structure of both steels were conducted. The as-received Russian steel was found to be in the annealed state. Only the fusion zone and the base metal were observed in the welded Russian steel. No visible heat affected zone was observed. Examination revealed that the as-received US steel was in the cold rolled condition. After welding, a fusion zone and a heat affected zone along with the base metal region were found.
Date: November 15, 1991
Creator: Chin, B. A.; Kee, C. K.; Wilcox, R. C. & Zinkle, S. J.
Object Type: Report
System: The UNT Digital Library
The Properties and Weldability of Materials for Fusion Reactor Applications (open access)

The Properties and Weldability of Materials for Fusion Reactor Applications

Low-activation austenitic stainless steels have been suggested for applications within fusion reactors. The use of these nickel-free steels will help to reduce the radioactive waste management problem after service. one requirement for such steels is the ability to obtain sound welds for fabrication purposes. Thus, two austenitic Fe-Cr-Mn alloys were studied to characterize the welded microstructure and mechanical properties. The two steels investigated were a Russian steel (Fe-11.6Cr19.3Mn-0.181C) and an US steel (Fe-12.lCr-19.4Mn-0.24C). Welding was performed using a gas tungsten arc welding (GTAW) process. Microscopic examinations of the structure of both steels were conducted. The as-received Russian steel was found to be in the annealed state. Only the fusion zone and the base metal were observed in the welded Russian steel. No visible heat affected zone was observed. Examination revealed that the as-received US steel was in the cold rolled condition. After welding, a fusion zone and a heat affected zone along with the base metal region were found.
Date: November 15, 1991
Creator: Chin, B. A.; Kee, C. K.; Wilcox, R. C. & Zinkle, S. J.
Object Type: Report
System: The UNT Digital Library
Accelerated line-by-line calculations for the radiative transfer of trace gases related to climate studies. Progress report No. 1, 15 September 1993--14 September 1994 (open access)

Accelerated line-by-line calculations for the radiative transfer of trace gases related to climate studies. Progress report No. 1, 15 September 1993--14 September 1994

In the present study we are studying the effects of including carbon dioxide, ozone, methane, and the halocarbons in addition to water vapor in the radiating atmosphere. The study has focused on two principal issues: the effect on the spectral fluxes and cooling rates of carbon dioxide, ozone and the halocarbons at 1990 concentration levels and the change in fluxes and cooling rates as a consequence of the anticipated ten year change in the profiles of these species. For the latter study the water vapor profiles have been taken as invariant in time. The radiative line-by-line calculations using LBLRTM (Line-By-Line Radiative Transfer Model) have been performed for tropical (TRP), mid-latitude winter (MLW) and mid-latitude summer (MLS) model atmospheres. The halocarbons considered in the present study are CCl{sub 4}, CFC-11, CFC-12 and CFC-22. In addition to considering the radiative effects of carbon dioxide at 355 ppM, the assumed current level, we have also obtained results for doubled carbon dioxide at 710 ppM. An important focus of the current research effort is the effect of the ozone depletion profile on atmospheric radiative effects.
Date: November 15, 1993
Creator: Clough, S. A.
Object Type: Report
System: The UNT Digital Library
Particle deposition in human and canine tracheobronchial casts. Annual progress report (open access)

Particle deposition in human and canine tracheobronchial casts. Annual progress report

The aim of this work is to measure deposition patterns and efficiencies of aerosol particles within realistic, single-pathway physical models of the tracheobronchial airways of humans and experimental animals over a range of particle sizes for a variety of respiratory modes and rates. This will provide data needed to assess the dose to the bronchial epithelium from inhaled radon progeny. In prior grant years an empirical expression for diffusional deposition efficiency of particles in the upper airways was obtained based on experimental data collected in central airway casts. The work also provided new quantitative data of airflow distribution in a realistic central airway cast for two species for both steady and pulsatile inspiratory flow and for expiratory flow. Theoretical studies were then extended based on a developing flow model. We concluded that although the developing flow model is a better predictor of the data than assumption of parabolic flow, the predicted deposition is significantly lower than that predicted by our best fit equation. In the current year the experimental results were evaluated in terms of the parametric solution of the convective diffusion equation.
Date: November 15, 1991
Creator: Cohen, B. S.
Object Type: Report
System: The UNT Digital Library