Personnel neutron dosimetry using CR-39 foils (open access)

Personnel neutron dosimetry using CR-39 foils

We are using CR-39 foils for personnel nuetron dosimetry at the Lawrence Livermore National Laboratory. We have developed a three-step electrochemical etching procedure that includes low-frequency electrochemical etching at low frequency and at elevated temperatures. Our first etching step is at 60 Hz, 3000 V for 5 hours in a 60/sup 0/C oven using 6.5 N KOH. The second etching step consists of an additional 23-minute etch at 60/sup 0/C, 2.0 kHz, and 3000 V, which increases the track size and makes them relatively uniform in size. The final step is a 15-minute post etch at 60/sup 0/C, which gives the tracks a smoother appearance. The foils are etched in etch chambers that can etch up to 24 foils. Several of these chambers can be used simultaneously with a single power supply. These chambers are rugged and have been used daily for over a year. 8 refs., 6 figs., 1 tab.
Date: January 13, 1987
Creator: Hankins, D.E.; Homann, S. & Westermark, J.
Object Type: Article
System: The UNT Digital Library
Dynamics of heavy ion beams during longitudinal compression (open access)

Dynamics of heavy ion beams during longitudinal compression

Heavy ion beams with initially uniform line charge density can be compressed longitudinally by an order of magnitude in such a way that the compressed beam has uniform line charge density and velocity-tilt profiles. There are no envelope mismatch oscillations during compression. Although the transverse temperature varies along the beam and also varies with time, no substantial longitudinal and transverse emittance growth has been observed. Scaling laws for beam radius and transport system parameters are given.
Date: March 13, 1987
Creator: Ho, D.D.M.; Bangerter, R.O.; Lee, E.P.; Brandon, S. & Mark, J.W.K.
Object Type: Article
System: The UNT Digital Library
Microwave instabilities in Booster and AGS (open access)

Microwave instabilities in Booster and AGS

Microwave instabilities is evaluated for the Booster and AGS for the preparation of the relativistic heavy ion collider. We found that the Booster may require feedback system for the transverse instability at the high intensity proton operation. The coherent instability is not important for the nominal RhIC operational intensity.
Date: March 13, 1987
Creator: Lee, S. Y. & Zhao, X. F.
Object Type: Article
System: The UNT Digital Library
A new heavy-ion-beam driver model for the SAFIRE code (open access)

A new heavy-ion-beam driver model for the SAFIRE code

The heavy-ion-beam driver model that was developed by McDonnell Douglas Astronautics Corporation as part of the Heavy Ion Fusion System Assessment study has been incorporated into the SAFIRE code. The model calculates the cost and performance of an induction linear accelerator and the beam transport systems required to deliver the beam to the fusion chamber. The results are used within the SAFIRE code for economic evaluation of inertial confinement fusion electric power plants. This report briefly describes the subroutines that make up the driver model, defines the variables that were added to the SAFIRE code, and gives an example of the output for a calculation using the new driver model.
Date: March 13, 1987
Creator: Meier, W. R.
Object Type: Report
System: The UNT Digital Library
An overview of copper-laser development for isotope separation (open access)

An overview of copper-laser development for isotope separation

We have developed a copper-laser pumped dye-laser system that addresses all of the requirements for atomic vapor laser isotope separation. The requirement for high average power for the laser system has led to the development of copper-laser chains with injection-locked oscillators and multihundred-watt amplifiers. By continuously operating the Laser Demonstration Facility, we gain valuable data for further upgrade and optimization.
Date: March 13, 1987
Creator: Warner, B.E.
Object Type: Article
System: The UNT Digital Library
The present status of the LLNL Evaluated Charged Particle Library (ECPL) (open access)

The present status of the LLNL Evaluated Charged Particle Library (ECPL)

The present report is written with two purposes in mind: to summarize the charged-particle reactions that presently exist in Evaluated Charge Particle Library; and to list all of the low-Z charged-particle reactions for which data exist in the Livermore experimental data compilation. 2 tabs.
Date: March 13, 1987
Creator: Mac Gregor, M.H.
Object Type: Report
System: The UNT Digital Library
Stress control of seismicity patterns observed during hydraulic fracturing experiments at the Fenton Hill hot dry rock geothermal energy site, New Mexico (open access)

Stress control of seismicity patterns observed during hydraulic fracturing experiments at the Fenton Hill hot dry rock geothermal energy site, New Mexico

Seismicity accompanying hydraulic injections into granitic rock is often diffuse rather than falling along a single plane. This diffuse zone of seismicity cannot be attributed to systematic errors in locations of the events. It has often been asserted that seismicity occurs along preexisting joints in the rock that are favorably aligned with the stress field so that slip can occur along them when effective stress is reduced by increasing pore fluid pressure. A new scheme for determining orientations and locations of planes along which the microearthquakes occurred was recently developed. The basic assumption of the method, called the three point method, is that many of the events fall along well defined planes; these planes are often difficult to identify visually in the data because planes of many orientations are present. The method has been applied to four hydraulic fracturing experiments conducted at Fenton Hill as part of a hot dry rock geothermal energy project. While multiple planes are found for each experiment; one plane is common to all experiments. The ratio of shear to normal stress along planes of all orientations is calculated using a best estimate of the current stress state at Fenton Hill. The plane common to all …
Date: April 13, 1987
Creator: Fehler, M. C.
Object Type: Article
System: The UNT Digital Library
Cores from the Salton Sea scientific drilling program: Metamorphic reaction progress as a function of chemical and thermal environment: Final report (open access)

Cores from the Salton Sea scientific drilling program: Metamorphic reaction progress as a function of chemical and thermal environment: Final report

The study investigated the downhole progressive metamorphism at the Salton Sea site by monitoring and evaluating discontinuous and continuous metamorphic reactions. The main emphasis was placed on: (1) the addition of petrographic, geochemical, and mineralogical data to the Salton Sea data base; (2) determination of downhole reactions; (3) evaluation of the progress of individual continuous reaction (epsilon) and the overall reaction progress (epsilon/sub T/) during the transition from one metamorphic zone to the next; and (4) evaluation and correlation of mineral reactions and reaction progress with mineral phase and organic material geothermometry. To these ends, thirty-three samples from the Salton Sea core were analyzed for: (1) quantitative modal mineralogy using the x-ray diffraction reference intensity method (RIM), (2) 30 major and trace elements in the whole rock and (3) mineral chemistry and structural state. In addition, a subset of these samples were used for temperature determinations using vitrinite reflectivity.
Date: May 13, 1987
Creator: Papike, J. J. & Shearer, C. K.
Object Type: Report
System: The UNT Digital Library
Ovecoming matrix organization problems in R and D (open access)

Ovecoming matrix organization problems in R and D

This paper describes ORNL's management of its fusion energy program. Guidelines for effective management are given. (JDH)
Date: May 13, 1987
Creator: Morgan, O. Bill
Object Type: Article
System: The UNT Digital Library
High Pressure Source/Cryostat Relief Solutions (open access)

High Pressure Source/Cryostat Relief Solutions

This report addresses solutions to the potential problem of cryostat over pressurization by the nominal 65 psi MWAP LAr source dewar. Uncontrolled (by reason of failure) filling of a 15 psi MW AP cryostat by the LAr fill line could cause over pressurization by overwhelming the provided cryostat relief system. Three levels of protection against over pressurization by the source dewar are mentioned in this report; the reduced (operational) relief pressure, the source pressure regulator, and the LAr dewar cooling loop. Only the first of these is recognized by the ASME code as sufficient protection, the others provide operational convenience and avoid the loss of detector fluid. Flow limiting device solutions are not considered because of the conflicting requirement to empty and fill the cryostats rapidly (within one eight hour shift), e.g. the movement of the cryostat from the assembly hall to the collision hall, or the inverse operation.
Date: August 13, 1987
Creator: Wintercorn, S. J. & Mulholland, G. T.
Object Type: Report
System: The UNT Digital Library
Ion dip spectroscopy of cold molecules and ions. Progress report and renewal proposal (open access)

Ion dip spectroscopy of cold molecules and ions. Progress report and renewal proposal

A research program is underway with the objective of developing techniques of high resolution multiphoton spectroscopy for selective, ultrasensitive molecular detection. Methods under study include various forms of ion dip spectroscopy and new methods of ion fragmentation spectroscopy. The studies are providing a new understanding of the fundamental spectroscopy and photophysics of large molecular ions. Dimer and cluster ions of polynuclear aromatics and related species are also being investigated, with potential detection applications.
Date: August 13, 1987
Creator: Wessel, J.
Object Type: Report
System: The UNT Digital Library
Transverse wake effects in an optical waveguide IFEL accelerator (open access)

Transverse wake effects in an optical waveguide IFEL accelerator

A recent proposal describes a project to build a short demonstration stage IFEL accelerator using as input beam the output of the Accelerator Test Facility high brightness linac (ATF) currently under construction at BNL. A second stage of the proposal involves the design and construction of a GeV IFEL accelerator. Both IFEL accelerators could be built using standard focussing as discussed in the proposal. While this is fairly natural in the short (60cm) demonstration accelerator, it requires multiple refocussing for the 1 GeV machine. It would therefore be valuable if an optical waveguide could be used to contain the laser beam over the full length of the accelerator. However, it is clear that if the use of a waveguide is to compete with the direct focussing method, the aperture of the waveguide must be comparable to the laser beam waist for a Rayleigh length of approx. = 30cm. In other words, the waveguide aperture must be at most a few mm. A natural concern for such close fitting structures is the effect of the wake fields produced in the waveguide by the beam. In particular, the wake fields produced by the front of the beam pulse may lead to Transverse …
Date: August 13, 1987
Creator: Sandweiss, J.
Object Type: Report
System: The UNT Digital Library
CC Cryostat Vacuum Pumping Efficiency (open access)

CC Cryostat Vacuum Pumping Efficiency

This report calculates the effect of the conductances of the pumping lines on the pumping speeds of the vacuum pumps being used to pump the inner vessel, and annular space, vacuum tight during the CC Cryostat testing. Effective pumping speeds were calculated for various values of pressure via the above stated formulas (see calculations). Conductances of valves, elbows, and tees were calculated with the help of ref. 1, and the volumes of the inner vessel and annular space were calculated wtth the aid of ref. 2. The major results of these calculations follow. The attached graphs show the effective pumping speed vs. pressure, as well as the pressure vs. pumpdown time for both the inner vessel pumpdown and the annular space pumpdown. Many intervals of pressure were chosen in order to give a complete picture of the effects on the pumping speed, and pumpdown time. An important rule of thumb is that the effective pumping speed be close to the intrinsic pump speed in the region of interest for the best efficiency. With an infinite conductance, these quantities become equal. In the case of the annular space pumpdown. the effective pumping speed is within approximately 15% of the intrinsic pump …
Date: October 13, 1987
Creator: Fitzpatrick, J.B.
Object Type: Report
System: The UNT Digital Library
Plasma Separation Process: Betacell (BCELL) code: User's manual. [Bipolar barrier junction] (open access)

Plasma Separation Process: Betacell (BCELL) code: User's manual. [Bipolar barrier junction]

The emergence of clearly defined applications for (small or large) amounts of long-life and reliable power sources has given the design and production of betavoltaic systems a new life. Moreover, because of the availability of the plasma separation program, (PSP) at TRW, it is now possible to separate the most desirable radioisotopes for betacell power generating devices. A computer code, named BCELL, has been developed to model the betavoltaic concept by utilizing the available up-to-date source/cell parameters. In this program, attempts have been made to determine the betacell energy device maximum efficiency, degradation due to the emitting source radiation and source/cell lifetime power reduction processes. Additionally, comparison is made between the Schottky and PN junction devices for betacell battery design purposes. Certain computer code runs have been made to determine the JV distribution function and the upper limit of the betacell generated power for specified energy sources. A Ni beta emitting radioisotope was used for the energy source and certain semiconductors were used for the converter subsystem of the betacell system. Some results for a Promethium source are also given here for comparison. 16 refs.
Date: November 13, 1987
Creator: Taherzadeh, M.
Object Type: Report
System: The UNT Digital Library
Thermal Regimes of Major Volcanic Centers: Magnetotelluric Constraints (open access)

Thermal Regimes of Major Volcanic Centers: Magnetotelluric Constraints

The focus of activity at this laboratory is on applying natural electromagnetic methods along with other geophysical techniques to studying the dynamical processes and thermal regimes associated with centers of major volcanic activity. We are presently emphasizing studies of the Long Valley/Mono Craters Volcanic Complex, the Cascades Volcanic Belt, and the Valles Caldera. This work addresses questions regarding geothermal energy, chemical transport of minerals in the crust, emplacement of economic ore deposits, and optimal siting of drill-holes for scientific purposes. In addition, since much of our work is performed in the intermontane sedimentary basins of the western US (along with testing our field-system in some of the graben structures in the Northeast), there is an application of these studies to developing exploration and interpretational strategies for detecting and delineating structures associated with hydrocarbon reserves.
Date: November 13, 1987
Creator: Hermance, J. F.
Object Type: Report
System: The UNT Digital Library
Ventilating-air change rate versus particulate contaminant spread (open access)

Ventilating-air change rate versus particulate contaminant spread

This study provides information on the spread of particulate contamination from glovebox leaks in plutonium manufacturing facilities, with emphasis on the effect of ventilating-air change rate on contaminated spread. A new, very sensitive aerosol tracer technique was developed to simulate plutonium aerosol leaks and its dispersion in a room. The tracer, a submicron aerosol of phloroglucinol, does not interfere with work activity and is detected by its ability to form ice crystals in a supercooled cloud. This technique was applied in Buildings 371 and 707 plutonium production areas. The tracer spread throughout the rooms in a few minutes and reached its equilibrium concentration in 10 to 25 min. Also, to clear the room of all tracer took about the same time. In one room, tracer concentration decreased proportionally to the air change rate, while in the second one, air change rate had no effect. This points out the need for air velocity data. Also, future work must include simultaneous particle concentration measurements at several points. 4 refs., 9 figs., 2 tabs.
Date: November 13, 1987
Creator: Langer, G. & Deitesfeld, C. A.
Object Type: Report
System: The UNT Digital Library