A High Efficiency, Kinetic-Ejection Negative Ion Source for RIB Generation (open access)

A High Efficiency, Kinetic-Ejection Negative Ion Source for RIB Generation

Chemically active radioactive species, diffused from RIB target materials, often arrive at the ionization chamber of the source in a variety of molecular forms. Because of the low probability for simultaneously dissociating and efficiently ionizing the individual atomic constituents of molecules with conventional hot-cathode electron-impact ion sources, the species of interest are often distributed in several mass channels in the form of molecular side-band beams and consequently, their intensities are diluted. The sputter negative ion beam generation technique offers an efficient means for simultaneously dissociating and ionizing highly electronegative atomic species present in molecular carriers. We have incorporated these principles in the design and fabrication of a kinetic ejection negative ion source and evaluated its potential for generating {sup 17,18}F{sup {minus}} beams for the Holifield Radioactive Ion Beam Facility astrophysics research program. The source utilizes Cs{sup +} beams to bombard condensable fluorine compounds that emanate from a target material, such as Al{sub 2}O{sub 3}, and are transported to the cooled inner surface of a conical-geometry cathode where they are adsorbed. The energetic Cs{sup +} beams efficiently dissociate these molecules and sputter their constituents. Since the work functions of cesiated surfaces are low, highly electronegative species such as fluorine are efficiently …
Date: October 5, 1998
Creator: Alton, G. D.; Liu, Y.; Murray, S. N. & Williams, C.
Object Type: Article
System: The UNT Digital Library
Plans for Constructing a Next-Generation ISOL Facility at ORNL (open access)

Plans for Constructing a Next-Generation ISOL Facility at ORNL

The U.S. Nuclear Science Community in its 1996 Long Range Plan identified an advanced radioactive ion beam (RIB) facility based on the ISOL technique as the next major facility to be constructed for U.S. nuclear physics. The proposed SpaHation Neutron Source (SNS) for Oak Ridge National Laboratory, whose construction design funds have recently been appropriated, offers a unique opportunity for the construction of this new facility, Plans for extracting a proton beam from the SNS, transporting it to the RIB facility, and constructing the new RIB facility at the SNS site are discussed, as are the ISOL targets, radiation handling, isobaric separation, acceleration of beams of radioactive experimental areas.
Date: October 5, 1998
Creator: Garrett, J.D.
Object Type: Article
System: The UNT Digital Library
ECR Ion Source Developments at the Oak Ridge National Laboratory (open access)

ECR Ion Source Developments at the Oak Ridge National Laboratory

New techniques for enhancing the performances of electron cyclotron resonance (ECR) ion sources are being investigated at the Oak Ridge National Laboratory. We have utilized the multiple discrete frequency technique to improve the charge state distributions extracted from conventional magnetic field geometry ECR source by injecting three frequencies into the source. A new flat central magnetic field concept, has been incorporated in the designs of a compact all-permanent-magnet source for high charge-state ion beam generation and a compact electromagnetic source for singly ionized radioactive ion beam generation for use in the Holifield Radioactive Ion Beam Facility (HRIBF) research program. A review of the three frequency injection experiments and descriptions of the design aspects of the "volume-type" ECR ion sources will be given in this report.
Date: October 5, 1998
Creator: Alton, G. D.; Liu, Y. & Meyer, F. W.
Object Type: Article
System: The UNT Digital Library
Spatial filter lens design for the main laser of the National Ignition Facility (open access)

Spatial filter lens design for the main laser of the National Ignition Facility

The National Ignition Facility (NIF), being designed and constructed at Lawrence Livermore National Laboratory (LLNL), comprises 192 laser beams The lasing medium is neodymium in phosphate glass with a fundamental frequency (1{omega}) of 1 053{micro}m Sum frequency generation in a pair of conversion crystals (KDP/KD*P) will produce 1 8 megajoules of the third harmonic light (3{omega} or {lambda}=351{micro}m) at the target The purpose of this paper is to provide the lens design community with the current lens design details of the large optics in the Main Laser This paper describes the lens design configuration and design considerations of the Main Laser The Main Laser is 123 meters long and includes two spatial filters one 13 5 meters and one 60 meters These spatial filters perform crucial beam filtering and relaying functions We shall describe the significant lens design aspects of these spatial filter lenses which allow them to successfully deliver the appropriate beam characteristic onto the target For an overview of NIF please see ``Optical system design of the National Ignition Facility,`` by R Edward English. et al also found in this volume.
Date: June 5, 1998
Creator: Korniski, R. J., Optics 1 Inc, Westlake Village, CA
Object Type: Article
System: The UNT Digital Library
Evaluation of the ISUS Power Management and Distribution System Under Operational Conditions (open access)

Evaluation of the ISUS Power Management and Distribution System Under Operational Conditions

An operational evaluation of the Integrated Solar Upper Stage (ISUS) power management and distribution (PMAD) system was conducted as part of the Engine Ground Demonstration thermionic power system test program-- START-3. START-3 testing took place at the Baikal Test Stand, located in the University of New Mexico's Energy Conversion Research Laboratory at the New Mexico Engineering Research Institute in Albuquerque, NM. One objective of this test was to evaluate the operational performance of the lSUS PMAD system developed by the National Aeronautics and Space Administration (NASA) Lewis Research Center. Tests of the PMAD with the ISUS diode string demonstrated that the PMAD could regulate the output of an array of thermionic converters within the design requirements and couId be modified to optimize performance for diode strings of fewer than 16 diodes.
Date: October 5, 1998
Creator: Button, R.M.; Luker, S.M.; Nelson, MAJ R.C. & Wyant, F.J.
Object Type: Article
System: The UNT Digital Library
Precision Studies of Nuclei (open access)

Precision Studies of Nuclei

This grant covers the period Sept. 1, 1994 to Aug. 31, 1996 with an extension to Dec. 31, 1996. The main activities funded by this research grant include work on the TJNAF (formerly CEBAF) Hall A data analysis software project and other projects in Hall A worked on by my graduate students. All of these projects are necessary for the functioning of Hall A and are therefore directly related to my Hall A research program. The Hall A experimental equipment is still in the commissioning phase with the first experiment expected to be performed in May of 1997. My effort has focused on software development, in particular on analyzing and calibrating the vertical drift chambers (VDCs) which will be used for particle tracking in the high resolution spectrometers. I have written a standalone program to determine calibration constants needed to obtain the ultimate position and angle resolution. High resolution performance will be paramount for much of the Hall A experimental program. In particular, I am spokesman on an experiment to separate the response functions in the d(e,e{prime}p)n reaction. In order to make meaningful comparisons with theory, this experiment requires accurate determination of the cross sections and it will therefore be …
Date: October 5, 1998
Creator: Ulmer, Paul E.
Object Type: Report
System: The UNT Digital Library
ACCOMPLISHMENTS OF THE AMERICAN-POLISH PROGRAM FOR ELIMINATION OF LOW EMISSIONS IN KRAKOW (open access)

ACCOMPLISHMENTS OF THE AMERICAN-POLISH PROGRAM FOR ELIMINATION OF LOW EMISSIONS IN KRAKOW

In 1991, US and Polish officials signed a Memorandum of Understanding formally initiating and directing the Cracow Clean Fossil Fuels and Energy Efficiency Program. Developing a program approach for the most effective use of the available funds required considerable effort on the part of all project participants. The team recognized early that the cost of solving the low emissions problem even in only one city far exceeded the amount of available US funds. Economic conditions in Poland limited availability of local capital funds for environmental projects. Imposing environmental costs on struggling companies or city residents under difficult conditions of the early 1990's required careful consideration of the economic and political impacts. For all of these reasons the program sought to identify technologies for achieving air quality goals which, through improved efficiency and/or reduced fuel cost, could be so attractive economically as to lead to self-sustaining activities beyond the end of the formal project. The effort under this program has been focused into 5 main areas of interest as follows: (1) Energy Conservation and Extension of Central Station District Heating; (2) Replacement of Coal- and Coke-Fired Boilers with Natural Gas-Fired Boilers; (3) Replacement of Coal-Fired Home Stoves with Electric Heating Appliances; …
Date: November 5, 1998
Creator: BUTCHER,T.A. & PIERCE,B.
Object Type: Article
System: The UNT Digital Library
Preliminary Ionization Efficiencies of {sup 11}C and {sup 14}O with the LBNL ECR Ion Sources (open access)

Preliminary Ionization Efficiencies of {sup 11}C and {sup 14}O with the LBNL ECR Ion Sources

High charge states, up to fully stripped {sup 11}C and {sup 14}O ion, beams have been produced with the electron cyclotron resonance ion sources (LBNL, ECR and AECR-U) at Lawrence Berkeley National Laboratory. The radioactive atoms of {sup 11}C and {sup 14}O were collected in batch mode with an LN{sub 2} trap and then bled into the ECR ion sources. Ionization efficiency as high as 11% for {sup 11}C{sup 4+} was achieved.
Date: October 5, 1998
Creator: Xie, Z.Q.; Cerny, J.; Guo, F.Q.; Joosten, R.; Larimer, R.M.; Lyneis, C.M. et al.
Object Type: Article
System: The UNT Digital Library
Hydrochlorofluorocarbon Reactivity and Structural Characterization of Zinc Exchanged NaX (open access)

Hydrochlorofluorocarbon Reactivity and Structural Characterization of Zinc Exchanged NaX

None
Date: July 5, 1998
Creator: Ciraolo, M. F.; Norby, P.; Hanson, J. C.; Corbin, D. R. & Grey, C. P.
Object Type: Article
System: The UNT Digital Library
Residual stresses due to processing of composite tubes (open access)

Residual stresses due to processing of composite tubes

X-ray and neutron diffraction were used to characterize residual stresses in composite tubing of a corrosion-resistant clad alloy on carbon steel. A useful X-ray method, based on the measurement of the fcc (3 1 1) reflection using Cr K{sub {beta}} radiation, was developed which allowed precise determination of surface residual stresses in the textured clad layer. Neutron diffraction measurements were carried out in both the carbon steel core and the clad layer, using the bcc (2 1 1) and fcc (3 1 1) reflections, respectively. The neutron diffraction results are consistent with surface residual stresses determined with X-ray diffraction. However, the through-thickness stress profiles established by X-ray and neutron diffraction do not agree with elastic calculations based on the thermal expansion mismatch between the carbon steel and clad alloy. The differences between the calculation and experimental results are discussed.
Date: February 5, 1998
Creator: Wang, X. L.; Hubbard, C. R.; Spooner, S.; Taljat, B. & Keiser, J. R.
Object Type: Report
System: The UNT Digital Library
Data analysis for preliminary conceptual model design, Vadose Zone Monitoring System (VZMS), McClellan AFB. 1997 annual report (open access)

Data analysis for preliminary conceptual model design, Vadose Zone Monitoring System (VZMS), McClellan AFB. 1997 annual report

Vadose zone investigations are being performed at site S-7 in IC 34, at McClellan AFB. At this location, a Vadose Zone Monitoring System (VZMS) is being used to collect subsurface data including hydraulic potential, soil gas pressure, moisture content, water chemistry, gas chemistry, and temperature. Although each individual data set is useful in improving the characterization of this contaminated site, the overall purpose of data collection is to provide input for the conceptual and numerical modeling of VOC transport in the vadose zone and the exchange of contaminants between the vadose zone and groundwater. In this report the authors submit a summary and preliminary analysis of the data collected through the end of 1997 and present it in the context of input for the impending modeling. This report merges findings from both the first and second half of 1997 and is presented as an annual report in lieu of two semi-annual reports, due to the fact that insufficient data had been collected up to mid June to allow a meaningful analysis.
Date: January 5, 1998
Creator: Zawislanski, P.T. & Oldenburg, C.M.
Object Type: Report
System: The UNT Digital Library
Monitoring and data analysis for the Vadose zone monitoring system (VZMS), McClellan AFB - Quarterly Status Report - 11/15/97-2/20/98 (open access)

Monitoring and data analysis for the Vadose zone monitoring system (VZMS), McClellan AFB - Quarterly Status Report - 11/15/97-2/20/98

None
Date: May 5, 1998
Creator: Zawislanski, P.; Mountford, H. S.; Dahlquist, R. & Rodriguez, S.
Object Type: Report
System: The UNT Digital Library
Terawatt Picosecond CO(sub 2) Laser Technology for High Energy Physics Applications (open access)

Terawatt Picosecond CO(sub 2) Laser Technology for High Energy Physics Applications

Demonstration of ultra-high acceleration gradients in the SM LWFA experiments put a next objective for the laser accelerator development to achieve a low-emittance monochromatic acceleration over extended interaction distances. The emerging picosecond terawatt (ps-TW) CO{sub 2} laser technology helps to meet this strategic goal. Among the considered examples are: the staged electron laser accelerator (STELLA) experiment, which is being conducted at the Brookhaven ATF, and the plasma-channeled LWFA. The long-wavelength and high average power capabilities of CO{sub 2} lasers maybe utilized also for generation of intense x-ray and gamma radiation through Compton back-scattering of the laser beams off relativistic electrons. We discuss applications of ps-TW CO{sub 2} lasers for a tentative {gamma}-{gamma} (or {gamma}-lepton) collider and generation of polarized positron beams.
Date: July 5, 1998
Creator: Pogorelsky, I. V.
Object Type: Article
System: The UNT Digital Library
Singular and nonlinear processes in applied mathematics. Final technical report (open access)

Singular and nonlinear processes in applied mathematics. Final technical report

A wide range of research topics were supported under this grant. These included: (1) complex space time singularities in nonlinear differential equations; (2) singularities in magneto-hydrodynamics; (3) the dynamics of knots and curves; and (4) the structure and dynamics of foams and grain boundaries. A brief summary of results achieved in each of these four areas is given below along with the associated publications acknowledging DOE support.
Date: August 5, 1998
Creator: Tabor, M.
Object Type: Report
System: The UNT Digital Library
Regulatory Closure Options for the Residue in the Hanford Site Single-Shell Tanks (open access)

Regulatory Closure Options for the Residue in the Hanford Site Single-Shell Tanks

Liquid, mixed, high-level radioactive waste (HLW) has been stored in 149 single-shell tanks (SSTS) located in tank farms on the U.S. Department of Energy's (DOE's) Hanford Site. The DOE is developing technologies to retrieve as much remaining HLW as technically possible prior to physically closing the tank farms. In support of the Hanford Tanks Initiative, Sandia National Laboratories has addressed the requirements for the regulatory closure of the radioactive component of any SST residue that may remain after physical closure. There is significant uncertainty about the end state of each of the 149 SSTS; that is, the nature and amount of wastes remaining in the SSTS after retrieval is uncertain. As a means of proceeding in the face of these uncertainties, this report links possible end-states with associated closure options. Requirements for disposal of HLW and low-level radioactive waste (LLW) are reviewed in detail. Incidental waste, which is radioactive waste produced incidental to the further processing of HLW, is then discussed. If the low activity waste (LAW) fraction from the further processing of HLW is determined to be incidental waste, then DOE can dispose of that incidental waste onsite without a license from the U.S. Nuclear Regulatory Commissions (NRC). The …
Date: October 5, 1998
Creator: Cochran, J.R. Shyr, L.J.
Object Type: Report
System: The UNT Digital Library
Rare earth magnetic order in RNi{sub 2}B{sub 2}C and RNiBC (open access)

Rare earth magnetic order in RNi{sub 2}B{sub 2}C and RNiBC

A review of neutron diffraction experiments on the magnetic order in the RNi{sub 2}B{sub 2}C and RNiBC (R-rare earth) systems is given. The RNi{sub 2}B{sub 2}C materials exhibit a wide variety of commensurate and incommensurate magnetic structures for different rare earths, along with superconductivity that is coupled to the magnetism. Simple commensurate antiferromagnetic structures are observed for R = Pr (T{sub N} = 4.0 K), Nd (T{sub N} = 4.8 K), Ho (T{sub N} = 8.5 K) and Dy (T{sub N} = 4.8 K). In addition, HoNi{sub 2}B{sub 2}C exhibits a c-axis spiral and an a-axis modulated incommensurate structure above 5 K, while both structures collapse in favor of the commensurate structure at low T. A transversely polarized spin density wave (SDW) type incommensurate structure is observed for Er (T{sub N} = 6.8 K) and Tm (T{sub N} = 1.5 K), while a longitudinally polarized SDW structure is observed for Tb (T{sub N} = 15 K). No magnetic ordering of any type is detected for Y, Ce and Yb. HoNiBC is an antiferromagnet (T{sub N} = 9.8 K), ErNiBC is a ferromagnetic (T{sub C} = 4.6 K), while TbNiBC and DyNiBC exhibit both ferromagnetic and antiferromagnetic ordering at 17 K …
Date: July 5, 1998
Creator: Skanthakumar, S. & Lynn, J.W.
Object Type: Report
System: The UNT Digital Library
STELLA Experiment: Design and Model Predictions (open access)

STELLA Experiment: Design and Model Predictions

The STaged ELectron Laser Acceleration (STELLA) experiment will be one of the first to examine the critical issue of staging the laser acceleration process. The BNL inverse free electron laser (EEL) will serve as a prebuncher to generate {approx} 1 {micro}m long microbunches. These microbunches will be accelerated by an inverse Cerenkov acceleration (ICA) stage. A comprehensive model of the STELLA experiment is described. This model includes the EEL prebunching, drift and focusing of the microbunches into the ICA stage, and their subsequent acceleration. The model predictions will be presented including the results of a system error study to determine the sensitivity to uncertainties in various system parameters.
Date: July 5, 1998
Creator: Kimura, W. D.; Babzien, M.; Ben-Zvi, Ilan; Campbell, L. P.; Cline, D. B.; Fiorito, R. B. et al.
Object Type: Article
System: The UNT Digital Library
Reduction of B-Integral Accumulation in Lasers (open access)

Reduction of B-Integral Accumulation in Lasers

A pulsed laser is provided wherein the B-integral accumulated in the laser pulse is reduced using a semiconductor wafer. A laser pulse is generated by a laser pulse source. The laser pulse passes through a semiconductor wafer that has a negative nonlinear index of refraction. Thus, the laser pulse accumulates a negative B-integral. The laser pulse is then fed into a laser amplification medium, which has a positive nonlinear index of refraction. The laser pulse may make a plurality of passes through the laser amplification medium and accumulate a positive B-integral during a positive non-linear phase change. The semiconductor and laser pulse wavelength are chosen such that the negative B-integral accumulated in the semiconductor wafer substantially cancels the positive B-integral accumulated in the laser amplification medium. There may be additional accumulation of positive B-integral if the laser pulse passes through additional optical mediums such as a lens or glass plates. Thus , the effects of self-phase modulation in the laser pulse are substantially reduced.
Date: June 5, 1998
Creator: Meyerhofer, David D. & Konoplev, Oleg A.
Object Type: Patent
System: The UNT Digital Library
Federal Emergency Management Information System (FEMIS) Bill of Materials (BOM) for FEMIS version 1.4.5 (open access)

Federal Emergency Management Information System (FEMIS) Bill of Materials (BOM) for FEMIS version 1.4.5

This document describes the hardware and software required for the Federal Emergency Management Information System version 1.4.5 (FEMIS v1.4.5). The FEMIS system is designed for a single Chemical Stockpile Emergency Preparedness Program (CSEPP) site that has multiple Emergency Operations Centers (EOCs). Each EOC has personal computers (PCs) that emergency planners and operations personnel use to do their jobs. These PCs are connected via a local area network (LAN) to servers that provide EOC-wide services. Each EOC is interconnected to other EOCs via a Wide Area Network (WAN). A UNIX server provides a platform to support the Oracle relational database management system (RDBMS) distributed by Pacific Northwest National Laboratory (PNNL), ARC/INFO geographic information system (GIS) capabilities (optional), basic file management services, the evacuation model (ESIM), the data exchange interface (DEI), and the notification service. FEMIS is a client/server system where much of the application software is located in the client PC. This client software includes the FEMIS application, government furnished dispersion and evacuation models, and Commercial-Off-The-Shelf (COTS) software applications, including the ArcView GIS and Microsoft Project (electronic planning). Several configurations are possible at a CSEPP site. In this document, a site is understood to include several installations of FEMIS, including the …
Date: June 5, 1998
Creator: Fangman, P.M.; Gerhardstein, L.H. & Homer, B.J.
Object Type: Report
System: The UNT Digital Library
POLARIZATION AND LUMINOSITY REQUIREMENTS FOR THE FIRST MUON COLLIDER. (open access)

POLARIZATION AND LUMINOSITY REQUIREMENTS FOR THE FIRST MUON COLLIDER.

None
Date: July 5, 1998
Creator: PARSA,Z.
Object Type: Article
System: The UNT Digital Library
Characterization of K{Sup +} Ion Exchange Into Na-Lsx Using Time Resolved Synchrotron X-Ray Powder Diffraction and Rietveld Refinement (open access)

Characterization of K{Sup +} Ion Exchange Into Na-Lsx Using Time Resolved Synchrotron X-Ray Powder Diffraction and Rietveld Refinement

None
Date: July 5, 1998
Creator: Lee,Y.; Cahill, C. L.; Hanson, J. C.; Parise, J. B.; Carr, S. W.; Myrick, M. L. et al.
Object Type: Article
System: The UNT Digital Library
Development of a radioactive ion beam test stand at LBNL (open access)

Development of a radioactive ion beam test stand at LBNL

For the on-line production of a {sup 14}O{sup +} ion beam, an integrated target--transfer line ion source system is now under development at LBNL. {sup 14}O is produced in the form of CO in a high temperature carbon target using a 20 MeV {sup 3}He beam from the LBNL 88'' Cyclotron via the reaction {sup 12}C({sup 3}He,n){sup 14}O. The neutral radioactive CO molecules diffuse through an 8 m room temperature stainless steel line from the target chamber into a cusp ion source. The molecules are dissociated, ionized and extracted at energies of 20 to 30 keV and mass separated with a double focusing bending magnet. The different components of the setup are described. The release and transport efficiency for the CO molecules from the target through the transfer line was measured for various target temperatures. The ion beam transport efficiencies and the off-line ion source efficiencies for Ar, O{sub 2} and CO are presented. Ionization efficiencies of 28% for Ar{sup +}, 1% for CO, 0.7% for O{sup +}, 0.33 for C{sup +} have been measured.
Date: October 5, 1998
Creator: Burke, J.; Freedman, S. J.; Fujikawa, B.; Gough, R. A.; Lyneis, C. M.; Vetter, P. et al.
Object Type: Article
System: The UNT Digital Library
Rheology of non-radioactive simulant of concentrated tetraphenylborate precipitate (open access)

Rheology of non-radioactive simulant of concentrated tetraphenylborate precipitate

This report presents rheological information on a simulated non-radioactive concentrated tetraphenylborate (TPB) precipitate.
Date: April 5, 1998
Creator: McLain, M. A. & Goren, I. D.
Object Type: Report
System: The UNT Digital Library
Femtosecond laser materials processing (open access)

Femtosecond laser materials processing

Femtosecond lasers enable materials processing of most any material with extremely high precision and negligible shock or thermal loading to the surrounding area. Applications ranging from drilling teeth to cutting explosives to precision cuts in composites are possible by using this technology. For material removal at reasonable rates, we have developed a fully computer-controlled 15-Watt average power, 100-fs laser machining system.
Date: August 5, 1998
Creator: Stuart, B
Object Type: Article
System: The UNT Digital Library