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Developing high brightness and high current beams for HIF injectors (open access)

Developing high brightness and high current beams for HIF injectors

The US Heavy Ion Fusion Virtual National Laboratory is continuing research into ion sources and injectors that simultaneously provide high current (0.5-1.0 Amps) and high brightness (normalized emittance better than 1.0 {pi}-mm-mr). The central issue of focus is whether to continue pursuing the traditional approach of large surface ionization sources or to adopt a multiaperture approach that transports many smaller ''beamlets'' separately at low energies before allowing them to merge. For the large surface source concept, the recent commissioning of the 2-MeV injector for the High Current eXperiment has increased our understanding of the beam quality limitations for these sources. We have also improved our techniques for fabricating large diameter aluminosilicate sources to improve lifetime and emission uniformity. For the multiaperture approach, we are continuing to study the feasibility of small surface sources and a RF induced plasma source in preparation for beamlet merging experiments, while continuing to run computer simulations for better understanding of this alternate concept. Experiments into both architectures will be performed on a newly commissioned ion source test stand at LLNL called STS-500. This stand test provides a platform for testing a variety of ion sources and accelerating structures with 500 kV, 17-microsecond pulses. Recent progress …
Date: May 24, 2002
Creator: Ahle, Larry; Grote, Dave & Kwan, Joe
System: The UNT Digital Library
Scalable Analysis Techniques for Microprocessor Performance Counter Metrics (open access)

Scalable Analysis Techniques for Microprocessor Performance Counter Metrics

Contemporary microprocessors provide a rich set of integrated performance counters that allow application developers and system architects alike the opportunity to gather important information about workload behaviors. These counters can capture instruction, memory, and operating system behaviors. Current techniques for analyzing data produced from these counters use raw counts, ratios, and visualization techniques to help users make decisions about their application source code. While these techniques are appropriate for analyzing data from one process, they do not scale easily to new levels demanded by contemporary computing systems. Indeed, the amount of data generated by these experiments is on the order of tens of thousands of data points. Furthermore, if users execute multiple experiments, then we add yet another dimension to this already knotty picture. This flood of multidimensional data can swamp efforts to harvest important ideas from these valuable counters. Very simply, this paper addresses these concerns by evaluating several multivariate statistical techniques on these datasets. We find that several techniques, such as statistical clustering, can automatically extract important features from this data. These derived results can, in turn, be feed directly back to an application developer, or used as input to a more comprehensive performance analysis environment, such as …
Date: July 24, 2002
Creator: Ahn, D H & Vetter, J S
System: The UNT Digital Library
Light-ion therapy in the U.S.: From the Bevalac to ?? (open access)

Light-ion therapy in the U.S.: From the Bevalac to ??

While working with E.O. Lawrence at Berkeley, R.R. Wilson in 1946 noted the potential for using the Bragg-peak of protons (or heavier ions) for radiation therapy. Thus began the long history of contributions from Berkeley to this field. Pioneering work by C.A. Tobias et al at the 184-Inch Synchrocyclotron led ultimately to clinical applications of proton and helium beams, with over 1000 patients treated through 1974 with high-energy plateau radiation; placing the treatment volume (mostly pituitary fields) at the rotational center of a sophisticated patient positioner. In 1974 the SuperHILAC and Bevatron accelerators at the Lawrence Berkeley Laboratory were joined by the construction of a 250-meter transfer line, forming the Bevalac, a facility capable of accelerating ions of any atomic species to relativistic energies. With the advent of these new beams, and better diagnostic tools capable of more precise definition of tumor volume and determination of the stopping point of charged-particle beams, large-field Bragg-peak therapy with ion beams became a real possibility. A dedicated Biomedical experimental area was developed, ultimately consisting of three distinct irradiation stations; two dedicated to therapy and one to radiobiology and biophysics. These facilities included dedicated support areas for patient setup and staging of animal and …
Date: September 24, 2002
Creator: Alonso, Jose R. & Castro, Joseph R.
System: The UNT Digital Library
How well do we know the electromagnetic form factors of the proton? (open access)

How well do we know the electromagnetic form factors of the proton?

Recent measurements of recoil polarization in elastic scattering have been used to extract the ratio of the electric to the magnetic proton form factors. These results disagree with Rosenbluth extractions from cross section measurements, indicating either an inconsistency between the two techniques, or a problem with either the polarization transfer or cross section measurements. To obtain precise knowledge of the proton form factors, they must first understand the source of this discrepancy.
Date: September 24, 2002
Creator: Arrington, J.
System: The UNT Digital Library
Coupled-Oscillator Model for Nonlinear Optical Activity (open access)

Coupled-Oscillator Model for Nonlinear Optical Activity

Describes linear optical activity which studies non linear optical activity of dimer-like chiral molecules.
Date: April 24, 2002
Creator: Belkin, M. A.; Shen, Y. R. & Flytzanis, C.
System: The UNT Digital Library
Research and Development for X-Ray Optics and Diagnostics on the Linac Coherent Source (LCLS) (open access)

Research and Development for X-Ray Optics and Diagnostics on the Linac Coherent Source (LCLS)

The Linac Coherent Light Source (LCLS) is a 1.5 to 15 {angstrom} wavelength Free-Electron Laser (PEL), under development at the Stanford Linear Accelerator Center (SLAC). The photon output consists of high brightness, transversely coherent pulses with duration < 300 fs, together with a broad spontaneous spectrum. The output energy density per unit area, pulse duration, repetition rate, and small FEL spot size pose special challenges for optical components and diagnostics downstream of the undulator. Planning for the photon beam transport, manipulation and diagnostics downstream of the undulator has begun.
Date: September 24, 2002
Creator: Bionta, R. M.; Arthur, J.; Chapman, H.; Craig, B.; Klingmann, J.; Kuba, J. et al.
System: The UNT Digital Library
Active and passive safety control performance in sub - critical, accelerator - driven nuclear reactors. (open access)

Active and passive safety control performance in sub - critical, accelerator - driven nuclear reactors.

Traditional safety performance requirements for nuclear reactors have been developed for critical reactors, whose kinetics characteristics differ significantly from sub-critical, accelerator-driven nuclear reactors. In a critical nuclear reactor, relatively small amounts of reactivity (negative or positive) can produce large changes in the fission rate. In sub-critical reactors, the self-multiplication (k) decreases as the sub-criticality (1-k) increases, and the responsiveness to small reactivity changes decreases. This makes sub-critical nuclear reactors less responsive to positive reactivity insertions than critical reactors. Also, larger negative reactivity insertions are needed in sub-critical reactors to shut down the fission chain if the neutron source remains. This paper presents the results from a computational analysis of the safety performance of sub-critical, accelerator-driven nuclear reactors. Coupled kinetics and thermal-hydraulics models are used to quantify the effectiveness of traditional protection and control system designs in sub-critical reactors. The analyses also quantify the role of inherent, passive reactivity feedback mechanisms in sub-critical reactors. Computational results are used to develop conclusions regarding the most favorable and effective means for reactor control and protection in sub-critical, accelerator-driven nuclear reactors.
Date: May 24, 2002
Creator: Cahalan, J. E. & Eriksson, M.
System: The UNT Digital Library
Ultrasound Imaging Using Diffraction Tomography in a Cylindrical Geometry (open access)

Ultrasound Imaging Using Diffraction Tomography in a Cylindrical Geometry

Tomographic images of tissue phantoms and a sample of breast tissue have been produced from an acoustic synthetic array system for frequencies near 500 kHz. The images for sound speed and attenuation show millimeter resolution and demonstrate the feasibility of obtaining high-resolution tomographic images with frequencies that can deeply penetrate tissue. The image reconstruction method is based on the Born approximation to acoustic scattering and is a simplified version of a method previously used by Andre (Andre, et. al., Int. J. Imaging Systems and Technology, Vol 8, No. 1, 1997) for a circular acoustic array system. The images have comparable resolution to conventional ultrasound images at much higher frequencies (3-5 MHz) but with lower speckle noise. This shows the potential of low frequency, deeply penetrating, ultrasound for high-resolution quantitative imaging.
Date: January 24, 2002
Creator: Chambers, D H & Littrup, P
System: The UNT Digital Library
Mesoscale modeling of grain boundary migration under stress using coupled finite element and meshfree methods. (open access)

Mesoscale modeling of grain boundary migration under stress using coupled finite element and meshfree methods.

The process of grain boundary migration involves moving interfaces and topological changes of grain boundary geometry. This can not be effectively modeled by Lagrangian, Eulerian, or arbitrary Lagrangian Eulerian finite element formulation when stress effect is considered. A coupled finite element and meshfree approach is proposed for modeling of grain boundary migration under stress. In this formulation, the material grid carries material kinematic and kinetic variables, whereas the grain boundary grid carries grain boundary kinematic variables. The material domain is discretized by a reproducing kernel partition of unity with built-in strain discontinuity across the grain boundaries. The grain boundaries, on the other hand, are discretized by the standard finite elements. This approach allows an arbitrary evolution of grain boundaries without continuous remeshing.
Date: May 24, 2002
Creator: Chen, J.-S.; Lu, H.; Moldovan, D. & Wolf, D.
System: The UNT Digital Library
Constraining the leading weak axial two-body current by SNO and Super-K (open access)

Constraining the leading weak axial two-body current by SNO and Super-K

We analyze the Sudbury Neutrino Observatory (SNO) and Super-Kamiokande (SK) data on charged current (CC), neutral current (NC) and neutrino electron elastic scattering (ES) reactions to constrain the leading weak axial two-body current parameterized by L{sub 1A}. This two-body current is the dominant uncertainty of every low energy weak interaction deuteron breakup process, including SNO's CC and NC reactions. Our method shows that the theoretical inputs to SNO's determination of the CC and NC fluxes can be self-calibrated, be calibrated by SK, or be calibrated by reactor data. The only assumption made is that the total flux of active neutrinos has the standard {sup 8}B spectral shape (but distortions in the electron neutrino spectrum are allowed). We show that SNO's conclusion about the inconsistency of the no-flavor-conversion hypothesis does not contain significant theoretical uncertainty, and we determine the magnitude of the active solar neutrino flux.
Date: October 24, 2002
Creator: Chen, Jiunn-Wei; Heeger, Karsten M. & Robertson, R.G. Hamish
System: The UNT Digital Library
Design and Testing of a Fast, 50 kV Solid-State Kicker Pulser (open access)

Design and Testing of a Fast, 50 kV Solid-State Kicker Pulser

The ability to extract particle beam bunches from a ring accelerator in arbitrary order can greatly extend an accelerator's capabilities and applications. A prototype solid-state kicker pulser capable of generating asynchronous bursts of 50 kV pulses has been designed and tested into a 50{Omega} load. The pulser features fast rise and fall times and is capable of generating an arbitrary pattern of pulses with a maximum burst frequency exceeding 5 MHz If required, the pulse-width of each pulse in the burst is independently adjustable. This kicker modulator uses multiple solid-state modules stacked in an inductive-adder configuration where the energy is switched into each section of the adder by a parallel array of MOSFETs. Test data, capabilities, and limitations of the prototype pulser are described.
Date: June 24, 2002
Creator: Cook, E. G.; Hickman, B. C.; Lee, B. S.; Hawkins, S. A.; Gower, E. J.; Allen, F. V. et al.
System: The UNT Digital Library
Implementation of x-ray microscopy and micro-XANES analysis for investigations of the cellular uptake and cellular metabolism of transition metals. (open access)

Implementation of x-ray microscopy and micro-XANES analysis for investigations of the cellular uptake and cellular metabolism of transition metals.

Micro-SRIXE (synchrotron-radiation-induced X-ray emission) and micro-XAS (X-ray absorption spectroscopy) were used to probe the uptake of exogenous metals by cells. The high flux and the sub-micron resolution of the hard X-ray microprobe, offer the experimenter the ability to obtain highly sensitive spatial and structural information of cellular elements. In this work the uptake of carcinogenic Cr(VI) was compared with that of a relatively non-toxic Cr(III) complex by micro-SRIXE mapping of whole cells. High intracellular Cr concentrations were observed in Cr(VI)-treated cells, while no significant Cr uptake was observed for Cr(III)-treated cells, as is consistent with uptake studies performed by other techniques. Micro-XANES analysis of Cr(V)- and Cr(VI)-treated cells showed that the predominant oxidation product following cellular metabolism was Cr(III). As shown by X-ray microscopic analysis of thin-sectioned cells, however, the reduction of Cr(VI) to Cr(III) did not occur at a fast enough rate to exclude Cr entry into the cell nucleus.
Date: October 24, 2002
Creator: Dillon, C. T.; Kennedy, B. J.; Lay, P. A.; Lai, B.; Cai, Z.; Stampfl, A. P. J. et al.
System: The UNT Digital Library
Progress in the development of superconducting quadrupoles for heavy ion fusion (open access)

Progress in the development of superconducting quadrupoles for heavy ion fusion

The Heavy Ion Fusion program is developing single aperture superconducting quadrupoles based on NbTi conductor, for use in the High Current Experiment at Lawrence Berkeley National Laboratory. Following the fabrication and testing of prototypes using two different approaches, a baseline design has been selected and further optimized. A prototype cryostat for a quadrupole doublet, with features to accommodate induction acceleration modules, is being fabricated. The single aperture magnet was derived from a conceptual design of a quadrupole array magnet for multi-beam transport. Progress on the development of superconducting quadrupole arrays for future experiments is also reported.
Date: May 24, 2002
Creator: Faltens, A.; Lietzke, A.; Sabbi, G.; Seidl, P.; Lund, S.; Manahan, B. et al.
System: The UNT Digital Library
Analog Amplitude Modulation of a High Voltage, Solid State Inductive Adder, Pulse Generator Using MOSFETS (open access)

Analog Amplitude Modulation of a High Voltage, Solid State Inductive Adder, Pulse Generator Using MOSFETS

High voltage, solid state, inductive adder, pulse generators have found increasing application as fast kicker pulse modulators for charged particle beams. The solid state, inductive adder, pulse generator is similar in operation to the linear induction accelerator. The main difference is that the solid state, adder couples energy by transformer action from multiple primaries to a voltage summing stalk, instead of an electron beam. Ideally, the inductive adder produces a rectangular voltage pulse at the load. In reality, there is usually some voltage variation at the load due to droop on primary circuit storage capacitors, or, temporal variations in the load impedance. Power MOSFET circuits have been developed to provide analog modulation of the output voltage amplitude of a solid state, inductive adder, pulse generator. The modulation is achieved by including MOSFET based, variable subtraction circuits in the multiple primary stack. The subtraction circuits can be used to compensate for voltage droop, or, to tailor the output pulse amplitude to provide a desired effect in the load. Power MOSFET subtraction circuits have been developed to modulate short, temporal (60-400 ns), voltage and current pulses. MOSFET devices have been tested up to 20 amps and 800 Volts with a band pass …
Date: June 24, 2002
Creator: Gower, E J & Sullivan, J S
System: The UNT Digital Library
Proof of Concept Test of a Unique Gaseous Perflurocarbon Tracer System for Verification and Long Term Monitoring of Caps and Cover Systems Conducted at the Savannah River Site Bentonite Mat Test Facility. (open access)

Proof of Concept Test of a Unique Gaseous Perflurocarbon Tracer System for Verification and Long Term Monitoring of Caps and Cover Systems Conducted at the Savannah River Site Bentonite Mat Test Facility.

Engineered covers have been placed on top of buried/subsurface wastes to minimize water infiltration and therefore, release of hazardous contaminants. In order for the cover to protect the environment it must remain free of holes and breaches throughout its service life. Covers are subject to subsidence, erosion, animal intrusion, plant root infiltration, etc., all of which will affect the overall performance of the cover. The U.S. Department of Energy Environmental Management (DOE-EM) Program 2006 Accelerated Cleanup Plan is pushing for rapid closure of many of the DOE facilities. This will require a great number of new cover systems. Some of these new covers are expected to maintain their performance for periods of up to 1000 years. Long-term stewardship will require monitoring/verification of cover performance over the course of the designed lifetime. In addition, many existing covers are approaching the end of their design life and will need validation of current performance (if continued use is desired) or replacement (if degraded). The need for a reliable method of verification and long-term monitoring is readily apparent. Currently, failure is detected through monitoring wells downstream of the waste site. This is too late as the contaminants have already left the disposal area. The …
Date: February 24, 2002
Creator: Heiser, J.; Sullivan, T. & Serrato, M.
System: The UNT Digital Library
Lethality in PARP-1/Ku80 double mutant mice reveals physiologicalsynergy during early embryogenesis (open access)

Lethality in PARP-1/Ku80 double mutant mice reveals physiologicalsynergy during early embryogenesis

Ku is an abundant heterodimeric nuclear protein, consisting of 70-kDa and 86-kDa tightly associated subunits that comprise the DNA binding component of DNA-dependent protein kinase. Poly(ADP)ribose polymerase-1 (PARP-1) is a 113-kDa protein that catalyzes the synthesis of poly(ADP-ribose) on target proteins. Both Ku and PARP-1 recognize and bind to DNA ends. Ku functions in the non-homologous end joining (NHEJ) repair pathway whereas PARP-1 functions in the single strand break repair and base excision repair (BER) pathways. Recent studies have revealed that PARP-1 and Ku80 interact in vitro. To determine whether the association of PARP-1 and Ku80 has any physiological significance or synergistic function in vivo, mice lacking both PARP-1 and Ku80 were generated. The resulting offspring died during embryonic development displaying abnormalities around the gastrulation stage. In addition, PARP-1-/-Ku80-/- cultured blastocysts had an increased level of apoptosis. These data suggest that the functions of both Ku80 and PARP-1 are essential for normal embryogenesis and that a loss of genomic integrity leading to cell death through apoptosis is likely the cause of the embryonic lethality observed in these mice.
Date: September 24, 2002
Creator: Henrie, Melinda S.; Kurimasa, Akihiro; Burma, Sandeep; Menissier-de Murcia, Josiane; de Murcia, Gilbert; Li, Gloria C. et al.
System: The UNT Digital Library
Underline Physics of E -  MEVVA Operation. (open access)

Underline Physics of E - MEVVA Operation.

Recently substantial enhancement of high ion charge states was clearly observed in both the HCEI and ITEP E-MEVVA ion sources. These experimental set-ups have two different methods of measuring the ion charge state distributions. The results can be considered as a proof of the E-MEVVA principle. These results sparked discussions regarding, which physics effects are dominant. Basic physics seems straightforward, an ion charge state in E-MEVVA is determined by the number of collisions with fast electrons versus the number of encounters with neutrals and lower charge state ions during an ion dwell time in the drift channel. However, the fluxes of fast electrons, lower charge state ions, and neutrals encountered by an ion may be a consequence of numerous effects. Factors determining neutral fluxes might be poor vacuum conditions, desorption of adsorbed gas by the electron beam directly or indirectly due to stacking (E-beam reflection) and/or instabilities that cause heating and desorption. Flux and energy of the fast electrons is primarily determined by the electron gun output. But significant contributions from electron beam stacking, instabilities, as well as plasma electron heating, are possible.
Date: June 24, 2002
Creator: Hershcovitch, A.; Batalin, V. A.; Bugaev, A. S.; Debolt, N.; Gushenets, V. I. & AL, E. T.
System: The UNT Digital Library
Use of Taus in ATLAS (open access)

Use of Taus in ATLAS

The total production rate for taus at a hadron collider is not a useful quantity. Taus must have significant transverse momentum (p{sub T}) in order to be observable. Leptonic decays of taus will yield isolated electrons or muons that can be detected but these can also be directly produced so discriminating their origin can be difficult. Hadronic decays of taus result in jets that must be distinguished from jets arising from QCD processes using the particle multiplicity and invariant mass. At the LHC, new particles can be expected that decay to final states involving taus. Examples are given from simulations by the ATLAS experiment showing how such final states can be exploited.
Date: October 24, 2002
Creator: Hinchliffe, Ian
System: The UNT Digital Library
Crystal structure of kappa-In2Se3 (open access)

Crystal structure of kappa-In2Se3

Structural properties of single-phase films of {kappa}-In{sub 2}Se{sub 3} and {gamma}-In{sub 2}Se{sub 3} were investigated. Both films were polycrystalline but their microstructure differed considerably. The a-lattice parameter of {kappa}-In{sub 2}Se{sub 3} has been measured. Comparison between these two materials indicates that {kappa}-In{sub 2}Se{sub 3} has a significantly larger unit cell ({Delta}c = 2.5 {+-} 0.2 % and {Delta}a = 13.5 {+-} 0.5%) and a structure more similar to the {alpha}-phase of In{sub 2}Se{sub 3}.
Date: October 24, 2002
Creator: Jasinski, J.; Swider, W.; Washburn, J.; Liliental-Weber, Z.; Chaiken, A.; Nauka, K. et al.
System: The UNT Digital Library
Glass dissolution rates from static and flow-through tests. (open access)

Glass dissolution rates from static and flow-through tests.

We measured the dissolution rate of a simple five-component glass at 70 C using static tests and single-pass flowthrough (SPFT) tests with pH buffers at pH values of 6.2, 8.3, and 9.6. The two methods yielded similar rates; however, the measured rates are about 10X higher than the rates measured previously for a glass having the same composition using an SPFT test method. Differences are attributed to how the effect of the solution flow rate on the glass dissolution rate was taken into account and how the surface area of crushed glass was estimated. The differences indicate the need to standardize the SPFT test procedure.
Date: May 24, 2002
Creator: Jeong, S.-Y. & Ebert, W. L.
System: The UNT Digital Library
Improvement in brightness of multicusp-plasma ion source (open access)

Improvement in brightness of multicusp-plasma ion source

The beam brightness of a multicusp-plasma ion source has been substantially improved by optimizing the source configuration and extractor geometry. The current density of a 2 keV He{sup +} beam extracted from a 7.5-cm-diameter source operating at 2.5 kW RF power is {approx}100 mA/cm{sup 2}, which is {approx}10 times larger than that of a beam extracted from a 5-cm-diameter source operating at 1 kW RF power. A smaller focused beam spot size is achieved with a counter-bored extractor instead of a conventional (''through-hole'') extractor, resulting another order of magnitude improvement in beam current density. Measured brightness can be as high as 440 A/cm{sup 2}Sr, which represents a 30 times improvement over prior work.
Date: May 24, 2002
Creator: Ji, Q.; Jiang, X.; King, T-J.; Leung, K. N.; Standiford, K. & Wilde, S.B.
System: The UNT Digital Library
Fernald vacuum transfer system for uranium materials repackaging (open access)

Fernald vacuum transfer system for uranium materials repackaging

The Fernald Environmental Management Project (FEMP) is the site of a former Department of Energy (DOE) uranium processing plant. When production was halted, many materials were left in an intermediate state. Some of this product material included enriched uranium compounds that had to be repackaged for shipment of off-site storage. This paper provides an overview, technical description, and status of a new application of existing technology, a vacuum transfer system, to repackage the uranium bearing compounds for shipment. The vacuum transfer system provides a method of transferring compounds from their current storage configuration into packages that meet the Department of Transportation (DOT) shipping requirements for fissile materials. This is a necessary activity, supporting removal of nuclear materials prior to site decontamination and decommissioning, key to the Fernald site's closure process.
Date: February 24, 2002
Creator: Kaushiva, Shirley; Weekley, Clint; Molecke, Martin & Polansky, Gary
System: The UNT Digital Library
WHAT ARE WE LEARNING FROM RHIC? (open access)

WHAT ARE WE LEARNING FROM RHIC?

Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory on Long Island, New York, began operation in 2000 culminating over ten years of development and construction, and a much longer period of theoretical speculations about the properties of hot QCD matter produced in nuclear collisions in the collider regime. RHIC's 2.4mile rings contain superconducting magnets, which operate at minus 451.6 degrees Fahrenheit, 4.5 degrees above the absolute zero. RHIC collides two intersecting heavy ion beams at center-of-mass energy of up to 200 GeV/A (at luminosity of up to 10{sup 26}sec{sup -1}cm{sup 2}, which can be further increased in the future), and polarized proton beams at c.m.s. energy of up to 500 GeV. The total energy in the gold-gold collision thus reaches 40 TeV, which is at present the World's record collision energy. In the pp mode, the unique possibility offered by RHIC for the first time is the study of double spin asymmetries and other spin observables. This talk is an attempt to summarize some of the first results obtained at RHIC. The author discusses the significance of these measurements for establishing the properties of hot and dense QCD matter and for understanding the dynamics of the theory at the …
Date: June 24, 2002
Creator: Kharzeev, D.
System: The UNT Digital Library
Status of the Fermilab electron cooling recirculation project (open access)

Status of the Fermilab electron cooling recirculation project

The electron cooling project requires a high current electron beam with high reliability to provide the consistent cooling required by Fermilab's physics program. We are using a 5URE-2 Pelletron to provide this beam. The program is developing a high current DC recirculating electron beam with high recovery efficiency. The present layout uses 2 sets of tubes with acceleration, a 180{sup o} bend, and deceleration for a total of about 10 meters of beam line. The project's nominal operating parameters are .5 A at 4.3 MeV with the emission cathode immersed in a 200-600 G magnetic field.
Date: October 24, 2002
Creator: Kroc, Thomas K
System: The UNT Digital Library