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open access

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. T… more
Date: 1988~
Creator: Huomo, H.; AsokaKumar, P.; Henderson, S. D.; Phlips, B. F.; Mayer, R.; McDonough, J. et al.
open access

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 trunca… more
Date: January 1, 1988
Creator: Bechtel, S. E.; Forest, M. G.; Holm, D. D. & Lin, K. J.
open access

2.0 K CEBAF Cryogenics

Description: No Description Available.
Date: October 1, 1988
Creator: Arenius, Dana; Chronis, William; Kashy, David; Keesee, Marie & Rode, Claus
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 … more
Date: January 1, 1988
Creator: Duvall, K. C.; Wasson, O. A. & Ma, Honchang
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 tra… more
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… more
Date: January 1, 1988
Creator: Pissanetzky, S. & Tompkins, P.
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… more
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 t… more
Date: 1988~
Creator: Jacobson, K. Bruce & Manos, Richard E.
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-perio… more
Date: October 3, 1988
Creator: Moretti, A.; Young, D.; Lee, G.; Mills, F. E.; Zhou, P.; Swenson, D. A. et al.
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 … more
Date: January 1, 1988
open access

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 th… more
Date: January 1, 1988
open access

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 … more
Date: January 1, 1988
open access

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 p… more
Date: January 1, 1988
open access

2D Full-Wave Modeling of ICRH With Finite E/Parallel/

Description: In this paper, the Oak Ridge ion cyclotron wave propagation code ORION has been extended to include nonzero E/parallel/ in both axisymmetric tokamak and helically symmetric stellarator geometries. Flux surfaces, conducting boundaries, and antennas can be of arbitrary shape, and antenna current is assumed to be divergence free (not a necessary assumption). Cartesian coordinates eliminate the singularity that occurs at the origin of cylindrical coordinate systems. In this paper we consider two al… more
Date: January 1, 1988
Creator: Batchelor, D. B.; Jaeger, E. F. & Weitzner, H.
open access

6th target fabrication specialists meeting: Proceedings, June 23, 1988 Sessions

Description: The following papers were presented at the meeting: Laser Target Fabrication at the Naval Research Laboratory; High-Sensitivity Radiography Detects Very Small Defects in Laser Fusion Targets; Ablation Layer Coating on Inertial Fusion Targets at Laboratory for Laser Energetics; X-Ray Microscopy of Inertial Fusion Targets Using a Laser Produced Plasma as an X-Ray Source; A Study of Factors Affecting The Deposition of Smooth Plasma Polymers; Composite Foams; Low-Density Resorcinol-Formaldehyde Foa… more
Date: January 1, 1988
open access

Ab initio studies of transition-metal dihydrogen chemistry

Description: Examples of transition metal complexes containing dihydrogen ligands are investigated using ab initio electronic structure calculations employing effective core potentials. Calculated geometrical structures and relative energies of various forms of WL/sub 5/(H/sub 2/) complexes (L = CO, PR/sub 3/) are reported, and the influence of the ligand on the relative stabilities of the dihydrogen and dihydride forms is studied. The possible intramolecular mechanisms for H/D scrambling are investigated i… more
Date: January 1, 1988
Creator: Kober, E. M. & Hay, P. J.
open access

Absolute calibration of a SPRED (Spectrometer Recording Extended Domain) EUV (extreme ultraviolet) spectrograph for use on the DIII-D tokamak

Description: We have performed an absolute intensity calibration of a SPRED multichannel EUV spectrograph using synchrotron radiation from the NBS SURF-II electron storage ring. The calibration procedure and results for both a survey grating (450 g/mm) and a high-resolution (2100 g/mm) grating are presented. The spectrograph is currently in use on the DIII-D tokamak with a tangential line-of-sight at the plasma midplane. Data is first acquired and processed by a microcomputer; the absolute line intensities … more
Date: January 1, 1988
Creator: Wood, R. D. & Allen, S. L.
open access

AC magnetic measurements of the ALS Booster Synchrotron Dipole Magnet engineering model

Description: We made a minimal set of AC magnetic measurements of the engineering model of the ALS Booster Dipole Magnet as part of the process of qualifying its design for production. Magnetic induction integrals over paths approximating electron-beam trajectories were measured with long curved coils connected to an electronic integrator. Magnetic induction was measured with point coils and an integrator and independently with a Hall-effect Gaussmeter. These quantities, and magnet current, were displayed o… more
Date: September 1, 1988
Creator: Green, M.I.; Hoyer, E.; Keller, R. & Nelson, D.H.
open access

Accelerated aging of cellulose by laser irradiation. [Development for Shroud of Turin]

Description: We describe a new technique for studying thermally-induced chemical transformations in cellulose developed for the Shroud of Turin. The apparatus consists of a carbon dioxide laser for heating, an infrared thermometer, and an optical reflectance spectrometer for tracking the progressive discoloration of the sample. To illustrate the technique, we present measurements from a single piece of sample linen along five isotherms in the range 200-290/degree/C. The results are explained in terms of fir… more
Date: January 1, 1988
Creator: Jackson, J. P.; Arthurs, E.; Schwalbe, L. A.; Sega, R. M.; Windish, D.; Long, W. H. et al.
open access

Accelerating structure with linear excitation

Description: The switched power linac (SPL) structures require a ring-shaped laser beam pulse of uniform intensity to avoid transverse field components of the accelerating field at the center. In order to also utilize the reflection of the outgoing EM wave, the switching element has to be very close to the outer edge of the structure to ensure nearly synchronous superposition at the beam hole with the original inward going wave. It is sometimes easier to produce linear (flat) laser beams, e.g., from powerfu… more
Date: March 1, 1988
Creator: Fischer, J. & Srinivasan-Rao, T.
open access

Acceleration, current amplification and emittance in MBE-4, an experimental beam induction linear accelerator for heavy ions

Description: We report on the implementation of a second schedule of acceleration and current amplification in MBE-4. Control of the beam current within the bunch is improved over that in the first schedule by the addition of several small amplitude induction pulsers to compensate for acceleration errors and to control the ends of the bunch. Measurements of the longitudinal and transverse emittance are presented. 5 refs., 3 figs., 1 tab.
Date: October 1, 1988
Creator: Warwick, A. I.; Gough, D. E.; Keefe, D. & Meuth, H.
open access

Acceleration of compact toroid plasma rings for fusion applications

Description: We describe experimental results for a new type of collective accelerator based on magnetically confined compact torus (CT) plasma rings and discuss applications to both inertial and magnetic fusion. We have demonstrated the principle of CT acceleration in the RACE device with acceleration of 0.5 mg ring masses to 400 km/s and 0.02 mg ring masses to 1400 km/s at greater than or equal to30% efficiency. Scaling the CT accelerator to the multi-megajoule level could provide an efficient, economical… more
Date: August 26, 1988
Creator: Hartman, C. W.; Barr, W. L.; Eddleman, J. L.; Gee, M.; Hammer, J. H.; Ho, S. K. et al.
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