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A 0. 5 to 3. 0 MeV monoenergetic positron beam

Description: An adjustable, 0.5--3 MeV monoenergetic positron beam has been constructed at Brookhaven. Currently a /sup 22/Na source with a W(100) foil transmission moderator produces a 1.1 mm FWHN beam with an intensity of 3/times/10/sup 5/ e/sup +//sec at a target located downstream from the accelerator. The divergence of the beam is less than 0.1/degree/ at 2.2 MeV energy. A SOA gun with 2 lens transport system brings the beam to a focus at the entrance of an electrostatic 3 MeV Dynamitron accelerator. The post acceleration beam transport system comprises 3 focusing solenolds, 4 sets of steering magnets and a 90/degree/ double focusing bending magnet. The beam energy spread at the target is <1 keV FWHN deduced from the beam size. Below we describe the positron extraction optics and acceleration, the construction of the beamline and the beam diagnostic devices. The salient beam parameters are listed at the end of this paper. 2 refs., 3 figs., 1 tab.
Date: 1988~
Creator: Huomo, H.; AsokaKumar, P.; Henderson, S. D.; Phlips, B. F.; Mayer, R.; McDonough, J. et al.
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1-D closure models for slender 3-D viscoelastic free jets: von Karman flow geometry and elliptical cross section

Description: In this paper we derive one space dimensional, reduced systems of equations (1-D closure models) for viscoelastic free jets. We begin with the three-dimensional system of conservation laws and a Maxwell-Jeffreys constitutive law for an incompressible viscoelastic fluid. First, we exhibit exact truncations to a finite, closed system of 1-D equations based on classical velocity assumptions of von Karman. Next, we demonstrate that the 3-D free surface boundary conditions overconstrain these truncated systems, so that only a very limited class of solutions exist. We then proceed to derive approximate 1-D closure theories through a slender jet asymptotic scaling, combined with appropriate definitions of velocity, pressure and stress unknowns. Our nonaxisymmetric 1-D slender jet models incorporate the physical effects of inertia, viscoelasticity (viscosity, relaxation and retardation), gravity, surface tension, and properties of the ambient fluid, and include shear stresses and time dependence. Previous special 1-D slender jet models correspond to the lowest order equations in the present asymptotic theory by an a posteriori suppression to leading order of some of these effects, and a reduction to axisymmetry. Solutions of the lowest order system of equations in this asymptotic analysis are presented: For the special cases of elliptical inviscid and Newtonian free jets, subject to the effects of surface tension and gravity, our model predicts oscillation of the major axis of the free surface elliptical cross section between perpendicular directions with distance down the jet, and drawdown of the cross section, in agreement with observed behavior. 15 refs.
Date: January 1, 1988
Creator: Bechtel, S. E.; Forest, M. G.; Holm, D. D. & Lin, K. J.
open access

2. 5 MeV neutron source for fission cross section measurement

Description: A 2.5 MeV neutron source has been established on the beamline of a 100 kV, 0.5 ma ion accelerator. The ion accelerator provides a 100 kV deuteron beam of about 200 ..mu..a into a 3 mm beam spot at the target position. The neutron source is produced by the D(d,n)/sup 3/He reaction with a yield of about 10/sup 7/ n/sec. The time-correlated associated particle method (TCAP) is utilized for the neutron fluence determination and for neutron background elimination. The /sup 3/He associated particles are detected at 90 degrees behind a thin aluminum foil and the corresponding neutrons are emitted at 73.5 degrees with an energy near 2.5 MeV. Also, the protons from the competing D(d,p)T reaction are monitored at 135 degrees for normalization and diagnostic purposes. A fission chamber containing six uranium tetrafluoride deposits has been designed for use in the /sup 235/U(n,f) cross section measurement at 2.5 MeV. The 5 cm diameter deposits range in thickness from 230--300 ..mu..g/cm/sup 2/ and are expected to have good uniformity. A description of the 2.5 MeV neutron source facility is presented along with details of the associated particle detection and neutron beam characteristics. Preparations for the fission cross section measurement are discussed. 6 refs., 4 figs.
Date: January 1, 1988
Creator: Duvall, K. C.; Wasson, O. A. & Ma, Honchang
open access

2-D emittance equation with acceleration and compression

Description: Since both acceleration and compression are required for an Inertial Fusion Driver, the understanding of their effect on the beam quality, emittance, is important. This report attempts to generalize the usual emittance formula for the drifting beam to include these effects. The derivation of the 2-D emittance equation is carried out and a comparison with the particle code results is given. The 2-D emittance at a given axial location is reasonable to consider for a long beam, particularly with velocity tilt; transverse emittance averaged over the entire bunch is not a useful quantity. 6 refs., 2 figs., 1 tab.
Date: October 1, 1988
Creator: Hahn, K. D. & Smith, L.
open access

2-D time evolution of T/sub e/ during sawtooth crash based on fast ECE (electron cyclotron emission) measurements on TFTR

Description: Electron cyclotron emission measurements taken at 20 locations in the horizontal midplane during a sawtooth crash have been analysed based on the assumption of fast rigid rotation of the plasma. Due to this fast rotation (approx.100..mu..sec), which remains fairly constant throughout the sawtooth crash, we have been able to make time-to-space reconstructions of half the poloidal plane using points which are separated in time by not more than 40..mu..sec. The existence of a temperature flattening in the precursor phase, which we interpret as an m = 1 temperature island, is clearly demonstrated, and its location and width agree well with local emissivity measurements from soft x-ray tomography viewing the same poloidal plane. The rotating temperature island in the precursor phase, the outward movement of the region of high T/sub c/ during the crash phase, and the shape of T/sub e/ during the crash phase, and the shape of T/sub e/ distribution after the crash during the successor phase have all been documented in a time sequence of color contours. 4 refs., 10 figs.
Date: December 1, 1988
Creator: Kuo-Petravic, G.
open access

A 2-MV multi-beam injector for heavy ion fusion

Description: Construction of a sixteen beam (0.5 A per beam) injector for use in scaled heavy ion fusion experiments is underway at LBL. The machine was designed and partially constructed at LANL. The injector is designed to use carbon arc sources which will provide 25 mA/cm/sup 2/ of extractable current density. The plasma from the arcs is confined electrostatically from drifting into the ion gun before firing the extraction pulse. The acceleration column consists of a set of aperture lenses which both transport the beam and attenuate backstreaming electrons. The acceleration column is mounted inside a 28-inch diameter brazed alumina insulating module. The high voltage for the injector is provided by an inductively loaded and graded Marx generator which resides inside a pressure vessel filled with a 65 psig mixture of 30/percent/ SF/sub 6/ and 70/percent/ N/sub 2/. Data is presented showing the performance of single and multiple carbon arc sources. Measurements show that adequate current density is available. Emittance measurements and efforts to improve emittance and reproducibility are shown. Tests with a 5-tray section of the full 18 tray generator are described showing the evolution of the generator design. 5 refs., 3 figs.
Date: June 1, 1988
Creator: Rutkowski, H. L.; Faltens, A.; Vanecek, D.; Pike, C.; Humphries, S. Jr. & Meyer, E. A.
open access

3-D magnetic field calculations for wiggglers using MAGNUS-3D

Description: The recent but steady trend toward increased magnetic and geometric complexity in the design of wigglers and undulators, of which tapered wigglers, hybrid structures, laced electromagnetic wigglers, magnetic cladding, twisters and magic structures are examples, has caused a need for reliable 3-D computer models and a better understanding of the behavior of magnetic systems in three dimensions. The capabilities of the MAGNUS-3D Group of Programs are ideally suited to solve this class of problems and provide insight into 3-D effects. MAGNUS-3D can solve any problem of Magnetostatics involving permanent magnets, linear or nonlinear ferromagnetic materials and electric conductors of any shape in space. The magnetic properties of permanent magnets are described by the complete nonlinear demagnetization curve as provided by the manufacturer, or, at the user's choice, by a simpler approximation involving the coercive force, the residual induction and the direction of magnetization. The ferromagnetic materials are described by a magnetization table and an accurate interpolation relation. An internal library with properties of common industrial steels is available. The conductors are independent of the mesh and are described in terms of conductor elements from an internal library.
Date: January 1, 1988
Creator: Pissanetzky, S. & Tompkins, P.
open access

3-D numerical analysis of a high-gain free-electron laser

Description: We present a novel approach to the 3-dimensional high-gain free- electron laser amplifier problem. The method allows us to write the laser field as an integral equation which can be efficiently and accurately evaluated on a small computer. The model is general enough to allow the inclusion of various initial electron beam distributions to study the gain reduction mechanism and its dependence on the physical parameters. 16 refs., 8 figs., 1 tab.
Date: October 19, 1988
Creator: Gallardo, J.C.
open access

A 3 TeV on 3 TeV proton-proton dedicated collider for Fermilab

Description: The Fermilab Dedicated Collider proposed in May 1983 is a 2 TeV on 2 TeV p)bar p) collider. The expected luminosity is )approximately) 10/sup 31/ cm/sup (minus/2)sec/sup )minus/1) and the estimated cost is )approximately) $362M (FY-83 dollars). Since 1983 both the superconducting magnet and the particle detector technologies have advanced and the countenance of physics, hence the desired characteristics of new facilities have also altered somewhat. We want to show here that with the new magnet technology used for the SSC one can construct a 3 TeV on 3 TeV pp collider on the Fermilab site. This pp Dedicated Collider )PPDC) will have a luminosity of about 10/sub 33/cm/sup )minus/2)sec)sup)minus)1) and a cost only )approximately) 50)percent) more than that of the p)bar p) Dedicated Collider. 3 figs
Date: March 30, 1988
Creator: Teng, L.C.
open access

A 4. pi. tracking magnetic spectrometer for RHIC

Description: A tracking magnetic spectrometer based on large Time Projection Chambers (TPC) was previously proposed to measure the momentum of charged particles emerging from the RHIC beam pipe at angles larger than four degrees and to identify the particle type for those beyond fifteen degrees with momenta up to 700 MeV/c, which is a large fraction of the final charged particles emitted by a low cm rapidity quark-gluon plasma. Experimental progress in the successful performance of a TPC developed for AGS E-810 is reported. We have also included typical results of our event generator which contains an interface of an improved HIJET and a plasma bubble model. Typical plasma signals one can expect from this model are presented. 4 refs., 9 figs.
Date: January 1, 1988
Creator: Lindenbaum, S. J.
open access

6-Acetyldihydrohomopterin and sepiapterin affect some GTP cyclohydrolase I's and not others

Description: The first enzyme in pteridine biosynthesis, GTP cyclohydrolase I, is a likely site for regulation of pteridine biosynthesis to occur. GTP cyclohydrolase I responds to hormonal treatment and is found altered in a variety of mice with genetically based neurological and immunological disorders. Genetic loci can greatly modify the activity of GTP cyclohydrolase: Punch mutant in Drosophila hph-1 in mouse and atypical phenylketonuria in human. This report examines the ability of Ahp and sepiapterin to alter the activity of GTP cyclohydrolase I from mouse liver, rat liver and Drosophila head. 20 refs., 2 tabs.
Date: 1988~
Creator: Jacobson, K. Bruce & Manos, Richard E.
open access

90-Ton Triple Cylinder Jack Design

Description: The three D-Zero cryostats (2 EC and 1 CC) will rest on three carriages which in turn ride on a set of hardened ways in the center beam. A pair of Tychoway rollers will be fitted to each of the four corners of the three carriages to provide the rolling support. In the final design, the two EC cryostats will be able to roll out and away from the CC cryostat in order to provide access to the space between each cryostat for maintenance and repairs. The cryostat will be frequently accessed, about once a month. during a collider run. The heaviest cryostat weighs about 360 tons. The large roller weight in one position for such a long period of time, created a concern about the rollers dimpling the hardened ways or even suffering permanent deformations themselves. There is also the possibility that the vertical position of the cryostat will need to be adjusted to align it with the beam line or that the carriage and cryostat will have to be lifted to remove and service the rollers. A device or system was needed to (1) relieve the weight of the cryostats from the rollers and the hardened ways, and (2) minimally adjust the vertical position of the cryostats, if necessary, and/or service the rollers. Compact hydraulic jacks seemed to be the answer. The first and foremost criteria was capacity. It was desired that the jacks be rated to twice the actual load. A jack is to be placed beside each roller, giving a total of eight per cryostat. The load per jack for a 360 ton cryostat would then be 45 tons, leaving 90 tons as the required capacity. The second and equally important criteria to be met was size. After installation of the Tychoway rollers. room to mount …
Date: September 26, 1988
Creator: Jaques, Al
open access

280 GHz Gyro-BWO design study: Final report

Description: This report summarizes the results of a design study of a 280 GHz Gyro-BWO tunable source. The purpose of this study is to identify and propose viable design alternatives for any significant technological risk associated with building an operational BWO system. The tunable Gyro-BWO system will have three major components: a Gyro-BWO microwave tube, a superconducting magnet, and a power supply/modulator. The design tasks for this study in order of decreasing importance are: design and specification of the superconducting magnet; preliminary design and layout of a Gyro-BWO microwave tube; and specification for the power supply/modulator. 2 refs., 4 figs.
Date: July 1, 1988
open access

An 805 MHz disk and washer structure for the Fermilab Linac Upgrade

Description: The Linac Upgrade program, a portion of the Tevatron Upgrade, calls for increasing the energy of the existing 200 MeV, 201.25 MHz linac to 400 MeV in order to reduce beam emittance degradation in the Booster. This is to be accomplished by replacing the last four Alvarez linac tanks with more efficient, higher gradient 805 MHz linac structure. One of the linac structures currently under study in a collaboration between Fermilab and SAIC is the Disk-and-Washer accelerating structure with bi-periodic tee supports, four per washer pair. This structure has a stop-band for the TM/sub 11/ mode (a problem in other designs) centered near the ..pi.. TM/sub 02/ accelerating mode frequency. A novel heat shrinking technique is used in the construction of a ten-cell one-meter long vacuum prototype structure. Description of the structure, testing techniques and test results are presented. 9 refs., 4 figs., 1 tab.
Date: October 3, 1988
Creator: Moretti, A.; Young, D.; Lee, G.; Mills, F.E.; Zhou, P.; Swenson, D.A. et al.
open access

1987 Annual Report on Low-Level Radioactive Waste Management Progress: Report to Congress in Response to Public Law 99-240

Description: In response to Section 7(b) of the Low-Level Radioactive Waste Policy Amendments Act of 1985 (Public Law 99-240), this report summarizes the progress of states and low-level radioactive waste compacts in 1987 in establishing new low-level waste disposal facilities. It also reports the volume of low-level waste received for disposal in 1987 by commercially operated low-level waste disposal facilities.
Date: August 1, 1988
open access

1987 Environmental Monitoring Report

Description: Sandia National Labortories conduct various research activities related to Department of Energy interests which have the potential for release of hazardous materials or radionuclides to the environment. A strict environmental control program places maximum emphasis on limiting releases. The environmental monitoring program conducted by Lawrence Livermore National Laboratory and augmented by Sandia is designed to measure the performance of the environmental controls. The program includes analysis of air, water, soil, vegetation, sewer effluent, ground water, and foodstuffs for various toxic, hazardous, or radioactive materials. Based on these studies, the releases of materials of concern at Sandia during 1987 were well below applicable Department of Energy standards. 8 refs., 3 figs., 12 tabs.
Date: April 1, 1988
Creator: Devlin, T.K.
open access

1988 DOE model conference proceedings: Volume 1

Description: These Proceedings of the October 3-7, 1988, DOE Model Conference are a compilation of the papers that were presented in the technical or poster sessions at the conference. Papers and posters not submitted for publication are not included in the Proceedings. The Table of Contents lists the titles of papers as well as the names of the presenters. These individuals are not, in all cases, the primary authors of the papers published. The actual title pages, appearing later with the papers, show the primary author(s) and all co-authors. The papers in all three volumes of the Proceedings appear as they were originally submitted for publication and have not been edited or changed in any way. Topics included in Volume 1 are Environmental Data Management, Site characterization technology, Wastewater treatment, Waste management in foreign countries, Transuranic waste management, and Groundwater characterization and treatment.
Date: January 1, 1988
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1988 DOE model conference proceedings: Volume 3

Description: These Proceedings of the October 3 - 7, 1988, DOE Model Conference are a compilation of the papers that were presented in the technical or poster sessions at the conference. Papers and posters not submitted for publication are not included in the Proceedings. The Table of Contents lists the titles of papers as well as the names of the presenters. These individuals are not, in all cases, the primary authors of the papers published. The actual title pages, appearing later with the papers, show the primary author(s) and all co-authors. The papers in all three volumes of the proceedings appear as they were originally submitted for publication and have not been edited or changed in any way. Topics included in Volume 3 include treatment of soils, waste characterization and certification, waste minimization site remediation management plans and programs, and training programs.
Date: January 1, 1988
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1988 DOE model conference proceedings: Volume 4

Description: These Proceedings of the October 3-7, 1988, DOE Model Conference are a compilation of the papers that were presented in the technical or poster sessions at the conference. Papers and posters not submitted for publication are not included in the Proceedings. The Table of Contents lists the titles of papers as well as the names of the presenters. These individuals are not, in all cases, the primary authors of the papers published. The actual title pages, appearing later with the papers, show the primary author(s) and all co-authors. The papers in all three volumes of the Proceedings appear as they were originally submitted for publication and have not been edited or changed in any way. Topics discussed in Volume 4 include site characterization and remediation projects, environmental monitoring and modeling; disposal site selection and facility design, risk assessment, safety and health issues, and site remediation technology.
Date: January 1, 1988
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1988 DOE model conference proceedings: Volume 5

Description: These Proceedings of the October 3--7, 1988 DOE Model Conference are a compilation of the papers that were presented in the technical or poster sessions at the conference papers and posters not submitted for publication are not included in the Proceedings. The Table of Contents lists the titles of papers as well as the names of the presenters. These individuals are not, in all cases, the primary authors of the papers published. The actual title pages, appearing later with the papers, show the primary author(s) and all co-authors. The papers in all three volumes of the Proceedings appear as they were originally submitted for publication and have not been edited or changed in any way. Topics discussed in Volume 5 include environmental assessments and program strategies, waste treatment technologies, and regulations and compliance studies.
Date: January 1, 1988
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1988 Federal Interim Storage Fee study: A technical and economic analysis

Description: This document is the latest in a series of reports that are published annually by Pacific Northwest Laboratory (PNL) for the US Department of Energy (DOE). The information in this report, which was prepared by E.R. Johnson Associates, Inc., under subcontract to PNL, will be used by the DOE to establish a payment schedule for interim storage of spent nuclear fuel under the Federal Interim Storage (FIS) Program. The FIS Program was mandated by the Nuclear Waste Policy Act of 1982. The information will be used to establish the schedule of charges for FIS services for the year commencing January 1, 1989. 13 refs.
Date: November 1, 1988
open access

29th Annual Report

Description: The ACIR Library is composed of publications that study the interactions between different levels of government. This document is an annual report.
Date: January 1988
Creator: United States. Advisory Commission on Intergovernmental Relations.
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