Wobbler facility for biomedical experiments at the Bevalac (open access)

Wobbler facility for biomedical experiments at the Bevalac

A new wobbler facility has been developed to deliver large uniform fields of relativistic heavy ions at the Bevalc without resorting to the use of scattering material in the beam. The charged particle beams are made to wobble and 'paint' a ring at the target by a pair of dipole magnets, which are placed tandem with their fields orthogonal to each other. The magnets are powered sinusoidally 90/sup 0/ out of phase with each other. By superimposing several rings of appropriate sizes and intensities, large uniform fields are produced. Up to 30 cm diameter fields with less than 5% variation in uniformity have been achived. Physics and biology measurements have been made to characterize the radiation field. 5 refs., 4 figs., 1 tab.
Date: May 1, 1985
Creator: Chu, W. T.; Curtis, S. B.; Llacer, J.; Renner, T. R. & Sorensen, R. W.
Object Type: Article
System: The UNT Digital Library
Feasibility of 81Br(Nu e-) 81Kr Solar Neutrino Experiment (open access)

Feasibility of 81Br(Nu e-) 81Kr Solar Neutrino Experiment

Several ingenious solutions have been offered for the solar neutrino problem - a defect in the solar model, the appearance of a new type of neutrino physics, the sun is no longer burning, etc. The range of these proffered solutions stresses the need for a new experiment to study the sun. The modern pulsed laser now makes possible a new solar neutrino test which examines an independent neutrino source in the sun. A recently proposed experiment would use the reaction /sup 81/Br(nu,e/sup -/)/sup 81/Kr to measure the flux of /sup 7/Be neutrinos from the sun. When /sup 7/Be decays by electron capture to make /sup 7/Li, a neutrino is emitted at 0.862 MeV and the flux of these on the earth is about 4 x 10/sup 9/ cm/sup -2/ s/sup -1/, according to the standard model. Therefore, an experiment based on /sup 81/Br(nu,e/sup -/)/sup 81/Kr which is sensitive to these lower energy neutrinos would be of fundamental importance. To first order, the chlorine experiment detects the /sup 8/B neutrinos while bromine detects the much more abundant /sup 7/Be neutrino source. In practice, the proposed bromine experiment would be very similar to the chlorine radiochemical experiment, except that /sup 81/Kr with …
Date: May 1, 1985
Creator: Hurst, G. S.; Allman, S. L.; Chen, C. H.; Kramer, S. D.; Thomson, J. O. & Cleveland, B.
Object Type: Article
System: The UNT Digital Library
Wobbler dosimetry for the biomedical program at the LBL Bevalac (open access)

Wobbler dosimetry for the biomedical program at the LBL Bevalac

A system for measuring delivered dose and dose distributions has been developed for use with the wobbler beam delivery system. The system allows rapid termination of an irradiation when hardware of software monitors indicate the required dose has been delivered. In addition several safeguard systems are required by such an active system in event of a failure of the wobbler, associated electronic hardware or the computer. Computer graphic displays allow operator monitoring of the irradiation on a pulse by pulse basis. 1 ref., 5 figs.
Date: May 1, 1985
Creator: Chu, W.; McEvoy, M.; Nyman, M.; Renner, T.; Gonzales, B.; Singh, R.P. et al.
Object Type: Article
System: The UNT Digital Library
Phenomenological model for stress corrosion cracking of Types 316NG and 316 stainless steel. [BWR] (open access)

Phenomenological model for stress corrosion cracking of Types 316NG and 316 stainless steel. [BWR]

A phenomenological model for both intergranular and transgranular stress corrosion cracking (SCC) in constant extension rate (CERT) tests is discussed. The model is based on an estimate of crack-tip strain rate obtained by use of a J-integral approach, a slip dissolution model for SCC, and a J-integral fracture criterion. The model is used to derive correlations between the SCC parameters (such as time to failure and average crack growth rate) and applied (nominal) strain rate. The model is extended to determine similar relationships between the SCC parameters and average near-crack-tip strain rate. The model predictions are compared with CERT test results obtained for Type 316NG stainless steel (SS) in water containing dissolved oxygen and impurities at 289/sup 0/C over a range of strain rates between 10/sup -5/ and 10/sup -7//s. Good agreement is obtained between the theoretical description and experimental results. The SCC behavior of Type 316NG SS is also compared with that of Type 316 SS to determine the relative SCC susceptibility of the two materials.
Date: May 1, 1985
Creator: Maiya, P.S.
Object Type: Article
System: The UNT Digital Library
Medical heavy ion accelerator proposals (open access)

Medical heavy ion accelerator proposals

For several decades, accelerators designed primarily for research in nuclear and high energy physics have been adapted for biomedical research including radiotherapeutic treatment of human diseases such as pituitary disorders, cancer, and more recently, arteriovascular malformations. The particles used in these treatments include pions, protons and heavier ions such as carbon, neon, silicon and argon. Maximum beam energies must be available to penetrate into an equivalent of about 30 cm of water, requiring treatment beams of 250 to 1000 MeV/nucleon. Certain special treatments of superficial melanoma, however, require that beam energies as low as 70 MeV/nucleon also be available. Intensities must be adequate to complete a 100 rad treatment fraction in about 1 minute. For most heavy ion treatments, this corresponds to 10/sup 7/-10/sup 9/ ions/second at the patient. Because this research is best conducted in a dedicated, hospital-based facility, and because of the clinical need for ultra-high reliability, the construction of new and dedicated facilities has been proposed. Heavy ion accelerators can provide a variety of ions and energies, permitting treatment plans that exploit the properties of the ion best suited to each individual treatment, and that employ radioactive beams (such as /sup 11/C and /sup 19/Ne) to precisely …
Date: May 1, 1985
Creator: Gough, R.A.
Object Type: Article
System: The UNT Digital Library
Ion implantation of boron in germanium (open access)

Ion implantation of boron in germanium

Ion implantation of /sup 11/B/sup +/ into room temperature Ge samples leads to a p-type layer prior to any post implant annealing steps. Variable temperature Hall measurements and deep level transient spectroscopy experiments indicate that room temperature implantation of /sup 11/B/sup +/ into Ge results in 100% of the boron ions being electrically active as shallow acceptor, over the entire dose range (5 x 10/sup 11//cm/sup 2/ to 1 x 10/sup 14//cm/sup 2/) and energy range (25 keV to 100 keV) investigated, without any post implant annealing. The concentration of damage related acceptor centers is only 10% of the boron related, shallow acceptor center concentration for low energy implants (25 keV), but becomes dominant at high energies (100 keV) and low doses (<1 x 10/sup 12//cm/sup 2/). Three damage related hole traps are produced by ion implantation of /sup 11/B/sup +/. Two of these hole traps have also been observed in ..gamma..-irradiated Ge and may be oxygen-vacancy related defects, while the third trap may be divacancy related. All three traps anneal out at low temperatures (<300/sup 0/C). Boron, from room temperature implantation of BF/sub 2//sup +/ into Ge, is not substitutionally active prior to a post implant annealing step of …
Date: May 1, 1985
Creator: Jones, K. S.
Object Type: Report
System: The UNT Digital Library
Workshop on e/sup +/e/sup -/ physics at high luminosities: proceedings (open access)

Workshop on e/sup +/e/sup -/ physics at high luminosities: proceedings

Separate abstracts were prepared for 10 papers in this workshop proceedings. (LEW)
Date: May 1, 1985
Creator: unknown
Object Type: Article
System: The UNT Digital Library
Developments in accelerators for heavy ion fusion (open access)

Developments in accelerators for heavy ion fusion

The long term goal of Heavy Ion Fusion (HIF) is the development of an accelerator with the large beam power, large beam stored-energy, and high brightness needed to implode small deuterium-tritium capsules for fusion power. While studies of an rf linac/storage ring combination as an inertial fusion driver continue in Japan and Europe, the US program in recent times has concentrated on the study of the suitability of linear induction acceleration of ions for this purpose. Novel features required include use of multiple beams, beam current amplification in the linac, and manipulation of long beam bunches with a large velocity difference between head and tail. Recent experiments with an intense bright beam of cesium ions have established that much higher currents can be transported in a long quadrupole system than was believed possible a few years ago. A proof-of-principle ion induction linac to demonstrate beam current amplification with multiple beams is at present being fabricated at LBL. 28 refs., 4 figs.
Date: May 1, 1985
Creator: Keefe, D.
Object Type: Article
System: The UNT Digital Library
Recent advances in the technology of superconducting accelerator magnets (open access)

Recent advances in the technology of superconducting accelerator magnets

Recent progress in technology of high-current-density cables for SSC model magnets is summarized. NbTi cable with J/sub c/ up to 50% higher than Tevatron cable can be expected. Magnetization effects can be predicted and corrected with several new techniques. Development of Superconductor with 2 to 3 ..mu..m filament diameter and high J/sub c/ is expected. 15 refs., 3 figs.
Date: May 1, 1985
Creator: Taylor, C.E.
Object Type: Article
System: The UNT Digital Library
Fish Passage Improvements at Three Mile Falls Diversion Dam, Umatilla River, Oregon, Final Completion Report. (open access)

Fish Passage Improvements at Three Mile Falls Diversion Dam, Umatilla River, Oregon, Final Completion Report.

This report contains the results and conclusions from the biological assessment and outlines several alternative plans for solving fish passage problems at the dam. A recommended plan, based on consensus of the fisheries agencies and the tribes, is described, and the rationale for that decision is discussed. Data needs for final designs, a tentative construction schedule, and a discussion of operation and maintenance needs are presented.
Date: May 1, 1985
Creator: Author, Unknown
Object Type: Report
System: The UNT Digital Library
Power combiners/dividers for loop pickup and kicker arrays for FNAL stochastic cooling rings (open access)

Power combiners/dividers for loop pickup and kicker arrays for FNAL stochastic cooling rings

The anti-proton accumulator and debuncher at FNAL will use stochastic methods to ''cool'' the beam. Pairs of quarter-wavelength directional-coupler loops are used to detect and kick the beam. The loops are copper plates which are flush with the upper and lower wall of a rectangular beam pipe. The plates, when surrounded by a properly sized pocket, form a 100-ohm transmission-line directional coupler. As the beam passes, a signal which gives position and time information, is induced in the plates. But, because the signal levels are low (<.5 picowatts per pair), a power combiner (usually several primary combiners feeding a secondary combiner) is used to combine the outputs of many loops. Subsequently, the combined signal is amplified, filtered and then fed into a divider, (that is, a combiner operating in reverse). The divider distributes the signal into a different set of loops which modify (kick) the beam's position. Since the loop couplers are arranged linearly, in arrays of various lengths, combiners also provide a convenient method of reducing the number of vacuum feedthroughs and preamplifiers and their related costs in performance and dollars. In this note we describe various stripline combiner systems that add the outputs of 4, 8, 16 or …
Date: May 1, 1985
Creator: Johnson, J. K. & Nemetz, R.
Object Type: Article
System: The UNT Digital Library
Beam profile monitor system for the Bevalac transfer line (open access)

Beam profile monitor system for the Bevalac transfer line

Incorporated in the current Bevalac transfer line upgrade project is a proposal for a new electronic beam monitoring system. It will be designed to amplify, convert, and transmit the signals of twelve 16 by 16 multi-wire grids to a central computer located in the Bevatron control room. Each station will contain interface amplifiers and a local microprocessor to convert wire grid currents into digitized values which will then be transmitted via a serial data channel to the main computer. The system will have a large dynamic range (1 nano to 1 milli-ampere of beam current), be designed for distributed operation, and will be easily expandable. This paper describes the basic electronic hardware and software components of the proposed system. 10 refs., 3 figs.
Date: May 1, 1985
Creator: Stover, G.
Object Type: Article
System: The UNT Digital Library
Suppression of propagating TE modes in the FNAL antiproton source stochastic beam cooling system (open access)

Suppression of propagating TE modes in the FNAL antiproton source stochastic beam cooling system

A method of attenuating the propagation of waveguide modes in the stochastic cooling array beam pipes to be utilized in the accumulator and debuncher rings of the Fermilab antiproton source is described. The attenuation method treated involves lining the vertical walls of the beam pipes with a ferrimagnetic material. The general solution for propagation in a nonhomogeneously loaded waveguide is presented along with numerical results specific to the antiproton source beam cooling system. Also described is a broadband, automated technique for the simultaneous measurement of complex ..mu.. and epsilon developed to aid in the characterization of different ferrite materials. Permittivity and permeability data for a typical ferrite are presented along with a discussion of the effects of these parameters on waveguide mode attenuation in the ferrite lined beam pipes.
Date: May 1, 1985
Creator: Barry, W.C.
Object Type: Report
System: The UNT Digital Library
Collective effects and lattice implications for an FEL bypass ring (open access)

Collective effects and lattice implications for an FEL bypass ring

Optimizing the performance of a single-pass free electron laser (FEL) in a storage ring requires a stored beam having both a relatively high volume density and a low momentum spread. These requirements place severe constraints on storage ring design due to the impact of both coherent and incoherent multiparticle phenomena. In this paper we present approximate scaling laws that elucidate the relative importance of various lattice parameters, and we will describe a systematic approach (embodied in the computer code ZAP) to parameter selection. 9 refs., 1 fig.
Date: May 1, 1985
Creator: Bisognano, J.; Jackson, A. & Zisman, M. S.
Object Type: Article
System: The UNT Digital Library
Brightness measurements on the Livermore high brightness test stand (open access)

Brightness measurements on the Livermore high brightness test stand

Several techniques using small radius collimating pipes with and without axial magnetic fields to measure the brightness of an extracted 1 - 2 kA, 1 - 1.5 MeV electron beam will be described. The output beam of the High Brightness Test Stand as measured by one of these techniques is in excess of 2 x 10/sup 5/ amp/cm/sup 2//steradian. 5 refs., 4 figs.
Date: May 9, 1985
Creator: Caporaso, G.J. & Birx, D.L.
Object Type: Article
System: The UNT Digital Library
Design of a three channel septum magnet (open access)

Design of a three channel septum magnet

A three channel septum magnet has been designed to service the three primary beam lines at the exit of the SuperHILAC. A pulsed switching magnet located in the next to last drift tube in the SuperHILAC poststripper diverts the beam +-1.09/sup 0/ into either the north or south port of the septum magnet. The central channel allows an undiverted beam to pass into another distribution magnet downstream. All channels may be active simultaneously and each may be tuned independently. Each septum channel contains four separate field regions and bends the beam 14.91/sup 0/. Various important aspects of the design, including geometry, material selection, thermal characteristics and power requirements, are discussed. 2 refs., 3 figs.
Date: May 1, 1985
Creator: Milburn, J.; Porter, J.; Tanabe, J.; Caylor, R. & Reimers, R.
Object Type: Article
System: The UNT Digital Library
Finding a rational nomenclature for mesons and baryons (open access)

Finding a rational nomenclature for mesons and baryons

A history of the Particle Data Group's efforts to find a rational and systematic convention for naming mesons and baryons is given. Several versions of our proposal are reviewed, and name changes which would occur are summarized. Some of the mail we have received is described. We hope to stimulate additional feedback.
Date: May 1, 1985
Creator: Barnett, R. M.; Cahn, R. N.; Gidal, G.; Rittenberg, A.; Trippe, T. G.; Wohl, C. G. et al.
Object Type: Article
System: The UNT Digital Library
New control techniques for extraction of bevalac beams (open access)

New control techniques for extraction of bevalac beams

Beams of accelerated heavy ions can now be delivered as one-second-long dc pulses with minimal fluctuations in instantaneous flux. Pulse duration can be held constant to within 1% while keeping a high non-varying extraction efficiency which minimizes pulse-to-pulse position shift in the extracted beam. In addition, differing beam intensities over several orders of magnitude can be delivered. Computer adjustment of all measurement and control devices results in linear operation over three orders of magnitude of beam intensity. Control of beam structure is accomplished by a unique combination of dual slope integrators and phase forward ''predictive'' circuits in the feedback loop.
Date: May 1, 1985
Creator: Nyman, M.; Chu, W.; Mehlman, B.; Mirer, W.; Oakley, H.; Renner, T. et al.
Object Type: Article
System: The UNT Digital Library
MBE-4, a heavy ion multiple-beam experiment (open access)

MBE-4, a heavy ion multiple-beam experiment

MBE-4, a heavy-ion multiple beam induction linac being built at LBL in FY85/86, will model many features of a much longer device. It will accelerate four space-charge-dominated cesium ion beams from, for example, 0.2 MeV, 5 mA/beam, 3.0 ..mu..sec, 1.6 m length at injection to approx.0.8 MeV, 15 mA/beam, 1.0 ..mu..sec, 1.1 m length at the exit. It will permit study of simultaneous focussing, acceleration, current amplification and emittance growth of multiple space-charge-dominated ion beams. Some features of this accelerator are described. 11 refs., 5 figs.
Date: May 1, 1985
Creator: Avery, R. T.; Chavis, C. S.; Fessenden, T. J.; Gough, D. E.; Henderson, T. F.; Keefe, D. et al.
Object Type: Article
System: The UNT Digital Library
Investigation of electromagnetic launcher behavior for impact fusion. Annual report, May 1, 1984-April 30, 1985 (open access)

Investigation of electromagnetic launcher behavior for impact fusion. Annual report, May 1, 1984-April 30, 1985

The second year of a 4-year program to develop an ultra-high velocity electromagnetic launcher has been completed, with significant progress made in the key technical areas. This lays firmly the cornerstone for major progress in Year 3 of the program. The launcher instrumentation and diagnostics system was developed. More than 20 launcher experiments were conducted using the SUVAC-I augmented launcher system. We tested our novel plasma generation technique using a lithium seeded propellant with encouraging success. We accelerated a 1.4 g projectile to 5.3 km/s in 1.6 m in the series. Unaugmented barrels for SUVAC-II were fabricated. The barrels were tested and commissioned with a total of 8 firings in single-stage configurations. The tests verified the basic soundness of the barrel mechanical and electrical design. Velocity up to 4.4 km/s was achieved with a 1.1 g projectile. Concurrently, we completed the fabrication, assembly and installation of SUVAC-II power supply (1 MJ) and its expanded control system. Experimentation with the multi-stage SUVAC-II launcher is expected to take place in the early part of Year 3. In the meantime, fabrication of the SUVAC-III power supply (an additional 0.4 MJ) has also been initiated.
Date: May 1, 1985
Creator: Thio, Y. C.
Object Type: Report
System: The UNT Digital Library
Synthesis of MBE-4 accelerating waveforms (open access)

Synthesis of MBE-4 accelerating waveforms

An ion induction linac for HIF must operate near the space charge current limit along most of its length. Small errors in the voltages applied to the accelerating gaps can readily produce local unwanted beam bunching and consequent beam loss. Uncompensated space charge forces will generate current loss from longitudinal beam spreading. In the design of the MBE-4 ideal acceleration voltages were developed that assure self-similar amplifying current waveforms at each position along the accelerator. These were approximately synthesized by adding waveforms that can be obtained from realizable electrical pulsers. A code is used to study effects produced by the imperfect synthesis on the longitudinal ion dynamics and beam current waveforms in the presence of space-charge forces.
Date: May 1, 1985
Creator: Kim, C. H.; Brady, V. O.; Fessenden, T. J.; Judd, D. L. & Laslett, L. J.
Object Type: Article
System: The UNT Digital Library
Evaluation and Modification of ASPEN Fixed-bed Gasifier Models for Inclusion in an Integrated Gasification Combined-Cycle Power Plant Simulation (open access)

Evaluation and Modification of ASPEN Fixed-bed Gasifier Models for Inclusion in an Integrated Gasification Combined-Cycle Power Plant Simulation

Several Advanced System for Process Engineering (ASPEN) fixed-bed gasifier models have been evaluated to determine which is the most suitable model for use in an integrated gasification combined-cycle (IGCC) power plant simulation. Four existing ASPEN models were considered: RGAS, a dry ash gasifier model developed by Halcon/Scientific Design Company; USRWEN, the WEN II dry ash gasifier model originally developed by C.Y. Wen at West Virginia University; the slagging gasifier model developed by Massachusetts Institute of Technology (MIT) and based on Continental Oil Company's (CONOCO) design study for the proposed Pipeline Demonstration Plant; and the ORNL dry ash gasifier model developed by Oak Ridge National Laboratory for the simulation of the Tri-States Indirect Liquefaction Process. Because none of the models studied were suitable in their present form for inclusion in an IGCC power plant simulation, the SLAGGER model was developed by making significant modifications to the MIT model. The major problems with the existing ASPEN models were most often inaccurate material and energy balances, limitations of coal type, or long run times. The SLAGGER model includes simplifications and improvements over the MIT model, runs quickly (less than 30 seconds of computer time on a VAX-11/780), and gives more accurate mass and …
Date: May 1, 1985
Creator: Stefano, J.M.
Object Type: Report
System: The UNT Digital Library
Multiwell Experiment: Reservoir Modeling Analysis, Volume II (open access)

Multiwell Experiment: Reservoir Modeling Analysis, Volume II

This report updates an ongoing analysis by reservoir modelers at the Morgantown Energy Technology Center (METC) of well test data from the Department of Energy's Multiwell Experiment (MWX). Results of previous efforts were presented in a recent METC Technical Note (Horton 1985). Results included in this report pertain to the poststimulation well tests of Zones 3 and 4 of the Paludal Sandstone Interval and the prestimulation well tests of the Red and Yellow Zones of the Coastal Sandstone Interval. The following results were obtained by using a reservoir model and history matching procedures: (1) Post-minifracture analysis indicated that the minifracture stimulation of the Paludal Interval did not produce an induced fracture, and extreme formation damage did occur, since a 65% permeability reduction around the wellbore was estimated. The design for this minifracture was from 200 to 300 feet on each side of the wellbore; (2) Post full-scale stimulation analysis for the Paludal Interval also showed that extreme formation damage occurred during the stimulation as indicated by a 75% permeability reduction 20 feet on each side of the induced fracture. Also, an induced fracture half-length of 100 feet was determined to have occurred, as compared to a designed fracture half-length of …
Date: May 1, 1985
Creator: Horton, A.I.
Object Type: Report
System: The UNT Digital Library
CSEM-steel hybrid wiggler/undulator magnetic field studies (open access)

CSEM-steel hybrid wiggler/undulator magnetic field studies

Current design of permanent magnet wiggler/undulators use either pure charge sheet equivalent material (CSEM) or the CSEM-Steel hybrid configuration. Hybrid configurations offer higher field strength at small gaps, field distributions dominated by the pole surfaces and pole tuning. Nominal performance of the hybrid is generally predicted using a 2-D magnetic design code neglecting transverse geometry. Magnetic measurements are presented showing transverse configuration influence on performance, from a combination of models using CSEMs, REC (H/sub c/ = 9.2 kOe) and NdFe (H/sub c/ = 10.7 kOe), different pole widths and end configurations. Results show peak field improvement using NdFe in place of REC in identical models, gap peak field decrease with pole width decrease (all results less than computed 2-D fields), transverse gap field distributions, and importance of CSEM material overhanging the poles in the transverse direction for highest gap fields.
Date: May 1, 1985
Creator: Halbach, K.; Hoyer, E.; Marks, S.; Plate, D. & Shuman, D.
Object Type: Article
System: The UNT Digital Library