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1/m<sub>c</sub> Terms in lambda<sup>+</sup><sub>c</sub> Semileptonic Decays

Description: We use the heavy quark effective theory to investigate the form factors that describe the semileptonic decays lambda<sup>+</sup><sub>c</sub> -> lambda e<sup>+</sup> nu, to order 1/m<sub>c</sub>. We find that a total of four form factors are needed to this order, in contrast with two form factors to leading order, and six form factors in the most general case. We point out some relationships that arise among the general form factors.
Date: February 1, 1992
Creator: Roberts, Winston

O(1/M{sup 3}) effects for heavy-light mesons in lattice NRQCD

Description: The masses of spin-singlet and spin-triplet S-wave mesons containing a single heavy quark are computed in the quenched approximation. The light quark action and gauge field action are both classically-improved and tadpole-improved, and the couplings to the heavy quark are organized by the 1/M expansion of tadpole-improved NRQCD. At each of two lattice spacings, near 0.22fm and 0.26fm, meson masses are obtained for heavy quarks spanning the region between charmed and bottom mesons. Results up to O(1/M), O(1/M{sup 2})and O(1/M{sup 3}) are displayed separately, so that the convergence of the heavy quark expansion can be discussed. Also, the effect of each term in the O(1/M{sup 3}) contribution is computed individually. For bottom mesons the 1/M-expansion appears to be satisfactory, but the situation for charmed mesons is less clear.
Date: March 1998
Creator: Lewis, Randy & Woloshyn, R. M.

1: Mass asymmetric fission barriers for {sup 98}Mo; 2: Synthesis and characterization of actinide-specific chelating agents

Description: Excitation functions have been measured for complex fragment emission from the compound nucleus {sup 98}Mo, produced by the reaction of {sup 86}Kr with {sup 12}C. Mass asymmetric fission barriers have been obtained by fitting the excitation functions with a transition state formalism. The extracted barriers are {approximately} 5.7 MeV higher, on average, than the calculations of the Rotating Finite Range Model (RFRM). These data clearly show an isospin dependence of the conditional barriers when compared with the extracted barriers from {sup 90}Mo and {sup 94}Mo. Eleven different liquid/liquid extractants were synthesized based upon the chelating moieties 3,2-HOPO and 3,4-HOPO; additionally, two liquid/liquid extractants based upon the 1,2-HOPO chelating moiety were obtained for extraction studies. The Pu(IV) extractions, quite surprisingly, yielded results that were very different from the Fe(III) extractions. The first trend remained the same: the 1,2-HOPOs were the best extractants, followed closely by the 3,2-HOPOs, followed by the 3,4-HOPOs; but in these Pu(IV) extractions the 3,4-HOPOs performed much better than in the Fe(III) extractions. 129 refs.
Date: August 1, 1996
Creator: Veeck, A. C.

A 1 MEGAWATT POLYPHASE BOOST CONVERTER-MODULATOR FOR KLYSTRON PULSE APPLICATION

Description: This paper describes electrical design criteria and first operational results a 140 kV, 1 MW average, 11 MW peak, zero-voltage-switching 20 kHz polyphase bridge, boost converter/modulator for klystron pulse application. The DC-DC converter derives the buss voltages from a standard 13.8 kV to 2300 Y substation cast-core transformer. Energy storage and filtering is provided by self-clearing metallized hazy polypropylene traction capacitors. Three ''H-Bridge'' Insulated Gate Bipolar Transistor (IGBT) switching networks are used to generate the polyphase 20 kHz transformer primary drive waveforms. The 20 kHz drive waveforms are chirped the appropriate duration to generate the desired klystron pulse width. PWM (pulse width modulation) of the individual 20 kHz pulses is utilized to provide regulated output waveforms with adaptive feedforward and feedback techniques. The boost transformer design utilizes amorphous nanocrystalline material that provides the required low core loss at design flux levels and switching frequencies. Resonant shunt-peaking is used on the transformer secondary to boost output voltage and resonate transformer leakage inductance. With the appropriate transformer leakage inductance and peaking capacitance, zero-voltage-switching of the IGBT's is attained, minimizing switching losses. A review of these design parameters and the first results of the performance characteristics will be presented.
Date: June 1, 2001
Creator: REASS, W.A.; DOSS, J.D. & GRIBBLE, R.F.

A-01 metals in stormwater runoff evaluation

Description: As a part of the A-01 investigation required by the NPDES permit, an investigation was performed to ascertain the concentrations of metals specifically copper (Cu), lead (Pb), and zinc (Zn) in stormwater being discharged through the outfall. This information would indicate whether all water being discharged would have to be treated or if only a portion of the discharged stormwater would have to be treated. A study was designed to accomplish this. The first goal was to determine if the metal concentrations increased, decreased, or remained the same as flow increased during a rain event. The second goal was to determine if the concentrations in the storm water were due to dissolved. The third goal was to obtain background data to ascertain if effluent credits could be gained due to naturally occurring metals.Samples from this study were analyzed and indicate that the copper and lead values increase as the flow increases while the zinc values remain essentially the same regardless of the flow rate. Analyses of samples for total metals, dissolved metals, TSS, and metals in solids was complicated because in all cases metals contamination was found in the filters themselves. Some conclusions can be derived if this problem is taken into account when analyzing the data. Copper concentrations in the total and dissolved fractions as well as the TSS concentrations followed the hydrograph at this outfall but the copper in solids concentration appeared to peak in the first flush and decline to nondetectable rapidly over the course of the storm event. Lead was present in the total analysis but not present in the dissolved fraction or the solids fraction of the samples. The data for zinc was interesting in that the dissolved fractions were higher than the total fraction in three out of four samples. This is probably due ...
Date: November 6, 1997
Creator: Eldridge, L. L.

1 MeV electron irradiation of solid Xe nanoclusters in Al : an in-situ HRTEM study.

Description: Thin film samples of a simple embedded nanocluster system consisting of solid Xe precipitates in Al have been subjected to 1 MeV electron irradiation in a high-voltage electron microscope. High-resolution images have been recorded on videotape in order to monitor the changes to the system resulting from the passage of electrons through the film. Inspection of the video recordings (in some cases frame-by-frame) reveals that complex, rapid processes occur under the electron beam. These include, movement of small clusters, coalescence of neighboring clusters, shape changes, the apparent melting and resolidification of the Xe, and the creation and annealing of extended defects within the Xe lattice. A tentative interpretation of some of the observations is presented in terms of the electron-induced displacement processes at the surface of the clusters.
Date: December 5, 1997
Creator: Donnelly, S. E.; Furuya, K.; Song, M.; Birtcher, R. C. & Allen, C. W.

1 mil gold bond wire study.

Description: In microcircuit fabrication, the diameter and length of a bond wire have been shown to both affect the current versus fusing time ratio of a bond wire as well as the gap length of the fused wire. This study investigated the impact of current level on the time-to-open and gap length of 1 mil by 60 mil gold bond wires. During the experiments, constant current was provided for a control set of bond wires for 250ms, 410ms and until the wire fused; non-destructively pull-tested wires for 250ms; and notched wires. The key findings were that as the current increases, the gap length increases and 73% of the bond wires will fuse at 1.8A, and 100% of the wires fuse at 1.9A within 60ms. Due to the limited scope of experiments and limited data analyzed, further investigation is encouraged to confirm these observations.
Date: May 1, 2013
Creator: Huff, Johnathon; McLean, Michael B.; Jenkins, Mark W. & Rutherford, Brian Milne

1. Mono((8)annulene)Uranium(4) half-sandwich complexes, 2. Novel syntheses of symmetrically substituted cyclooctatetetraenes

Description: A reproducible, high-yield synthesis of mono((8)annulene)uranium(4)dichloride (1) is reported, along with the X-ray crystal structural of the bis(pyridine) adduct. Metathesis reactions of the half-sandwich complex 1 with a variety of simple alkyl and alkoxy reagents failed to generate any isolable mono-ring complexes. Reactions of 1 with polydentate, delocalized anions did produce stable derivatives, including mono((8)annulene)uranium(4)bis(acetylacetonate) (4). An X-ray crystal structure of 4 is reported.
Date: October 1, 1991
Creator: Boussie, T. R.

1. Mono([8]annulene)Uranium(4) half-sandwich complexes, 2. Novel syntheses of symmetrically substituted cyclooctatetetraenes

Description: A reproducible, high-yield synthesis of mono([8]annulene)uranium(4)dichloride (1) is reported, along with the X-ray crystal structural of the bis(pyridine) adduct. Metathesis reactions of the half-sandwich complex 1 with a variety of simple alkyl and alkoxy reagents failed to generate any isolable mono-ring complexes. Reactions of 1 with polydentate, delocalized anions did produce stable derivatives, including mono([8]annulene)uranium(4)bis(acetylacetonate) (4). An X-ray crystal structure of 4 is reported.
Date: October 1, 1991
Creator: Boussie, T. R.

1/N

Description: There exist families of field theories with symmetry group SO(N) (or SU(N)) that become simpler as N becomes larger. More precisely, the solutions to these theories possess an expansion in powers of 1/N. This expansion is the subject of these lectures. The 1/N expansion can be used to analyze model field theories. The 1/N expansion is developed for phi/sup 4/ theory and applied to two two-dimensional models with similar combinatoric structures, the Gross-Neveu model and the CP/sup N-1/ model. These models display (in the leading 1/N approximation) such interesting phenomena as asymptotic freedom, dynamical symmetry breaking, dimensional transmutation, and non-perturbative confinement. It is possible that the 1/N expansion, with N the number of colors, might fruitfully be applied to quantum chromodynamics. Unfortunately, it is not possible to make a decisive test of the approximation, because no one knows how to compute even the first term in the expansion in closed form. However, it is possible to argue that this first term, whatever its detailed form, has many properties that are also shared by the real world, and which are otherwise underived from field theory. These include the saturation of scattering amplitudes by an infinite number of narrow resonances, the essential feature of dual-resonance models. (RWR)
Date: March 1, 1980
Creator: Coleman, S.

1+-n+ ECR ION SOURCE DEVELOPMENT TEST STAND

Description: A test stand for the investigation of 1+-n+ charge boosting using an ECR ion sources is currently being assembled at the Texas A&M Cyclotron Institute. The ultimate goal is to relate the charge-boosting of ions of stable species to possible charge-boosting of ions of radioactive species extracted from the diverse, low-charge-state ion sources developed for radioactive ion beams.
Date: April 7, 2006
Creator: May, Donald P.

1 nA beam position monitoring system

Description: A system has been developed at Jefferson Lab for measuring transverse position of very low current beams delivered to the Experimental Hall B of the Continuous Electron Beam Accelerator Facility (CEBAF). At the heart of the system is a position sensitive cavity operating at 1497 MHz. The cavity utilizes a unique design which achieves a high sensitivity to beam position at a relatively low cavity Q. The cavity output RF signal is processed using a down-converter and a commercial lock-in amplifier operating at 100 kHz. The system interfaces with a VME based EPICS control system using the IEEE, 488 bus. The main features of the system are simple and robust design, and wide dynamic range capable of handling beam currents from 1 nA to 1000 nA with an expected resolution better than 100 {mu}m. This paper outlines the design of the system.
Date: June 1, 1997
Creator: Ursic, R.; Flood, R. & Piller, C.

1 Outreach, Education and Domestic Market Enhancement 2 Export Promotion and Assistance

Description: Geothermal Energy Association supports the US geothermal industry in its efforts to bring more clean geothermal energy on-line throughout the world. Activities designed to accomplish this goal include: (1) developing and maintaining data bases, web pages, (2) commissioning of special studies and reports, (3) preparing, printing and distributing brochures and newsletters, (4) developing exhibits and displays, and participating in trade shows, (5) designing, producing and disseminating audio-video materials, (6) monitoring and coordinating programs carried out by US DOE and other Federal agencies, (7) holding workshops to facilitate communication between researchers and industry and to encourage their recognition of emerging markets for geothermal technology, (8) attending conferences, making speeches and presentation, and otherwise interacting with environmental and other renewable energy organizations and coalitions, (9) hosting events in Washington, DC and other appropriate locations to educate Federal, State and local representatives, environmental groups, the news media, and other about the status and potential of geothermal energy, (10) conducting member services such as the preparation and distribution of a member newsletter related to operating and maintaining s useful and viable association, and (11) performing similar kinds of activities designed to inform others about geothermal energy. The activities of the export promotion aim to assist industry in accomplishing the goal of successfully penetrating and developing energy in country with existing geothermal resources and a desire to develop them. Activities including in export promotion are: (1)needs analysis and assessment involve monitoring the progress of developing markets and projects overseas and working with US industry to determine what future activities by GEA would be of greatest assistance, (2) outreach includes the preparation and dissemination of brochures and videos for foreign professionals, officials and decision-makers as well as presentations of information of the geothermal technology and the capabilities of the US geothermal industry, (3) Market conditioning involves ...
Date: March 15, 2004
Creator: Geothermal Energy Association

S-1 project. Volume I. Architecture. 1979 annual report

Description: The US Navy is one of the world's largest users of digital computing equipment having a procurement cost of at least $50,000, and is the single largest such computer customer in the Department of Defense. Its projected acquisition plan for embedded computer systems during the first half of the 80s contemplates the installation of over 10,000 such systems at an estimated cost of several billions of dollars. This expenditure, though large, is dwarfed by the 85 billion dollars which DOD is projected to spend during the next half-decade on computer software, the near-majority of which will be spent by the Navy; the life-cycle costs of the 700,000+ lines of software for a single large Navy weapons systems application (e.g., AEGIS) have been conservatively estimated at most of a billion dollars. The S-1 Project is dedicated to realizing potentially large improvements in the efficiency with which such very large sums may be spent, so that greater military effectiveness may be secured earlier, and with smaller expenditures. The fundamental objectives of the S-1 Project's work are first to enable the Navy to be able to quickly, reliably and inexpensively evaluate at any time what is available from the state-of-the-art in digital processing systems and what the relevance of such systems may be to Navy data processing applications: and second to provide reference prototype systems to support possible competitive procurement action leading to deployment of such systems.
Date: January 1, 1979

S-1 project. Volume II. Hardware. 1979 annual report

Description: This volume includes highlights of the design of the Mark IIA uniprocessor (SMI-2), and the SCALD II user's manual. SCALD (structured computer-aided logic design system) cuts the cost and time required to design logic by letting the logic designer express ideas as naturally as possible, and by eliminating as many errors as possible - through consistency checking, simulation, and timing verification - before the hardware is built. (GHT)
Date: January 1, 1979

1-/sup 11/C-D-glucose and related compounds

Description: The novel compounds 1-/sup 11/C-D-glucose, 1-/sup 11/C-D-mannose, 1-/sup 11/C-D-galactose, 2-/sup 11/C-D-glucose, 2-/sup 11/C-D-mannose and 2-/sup 11/C-D-galactose which can be used in nuclear medicine to monitor the metabolism of glucose and galactose can be rapidly prepared by reaction of the appropriate aldose substrate with an alkali metal /sup 11/C-labeled cyanide followed by reduction with a Raney alloy in formic acid.
Date: January 26, 1982
Creator: Shiue, C.Y. & Wolf, A.P.

1 to 2 GeV/c beam line for hypernuclear and kaon research

Description: A kaon beam line operating in the range from 1.0 to 2.0 GeV/c is proposed. The line is meant for kaon and pion research in a region hitherto inaccessible to experimenters. Topics in hypernuclear and kaon physics of high current interest include the investigation of doubly strange nuclear systems with the K/sup -/,K/sup +/ reaction, searching for dibaryon resonances, hyperon-nucleon interactions, hypernuclear ..gamma.. rays, and associated production of excited hypernuclei. The beam line would provide separated beams of momentum analyzed kaons at intensities greater than 10/sup 6/ particles per spill with a momentum determined to one part in a thousand. This intensity is an order of magnitude greater than that currently available. 63 references.
Date: February 15, 1985
Creator: Chrien, R.E.

A 1- to 5-MW, RCS-based, short-pulse spallation neutron source

Description: Two accelerator configurations, the linac/compressor ring scheme and the linac/RCS scheme, are commonly used to provide the proton beam power for a short-pulse spallation neutron source. In one configuration, a full-power linac provides the beam power and a compressor ring shortens the pulse length from 1-ms down to 1 {micro}s. In the other, rapid cycling synchrotrons (RCSs) provide the beam power and also shorten the pulse length. A feasibility study of a staged approach to a 5-MW proton source utilizing RCS technology, allowing intermediate operation at 1 MW, was performed at ANL and is presented in this paper. This study is complementary to a study in progress at ORNL based on a linac and an accumulator ring. The 1-MW facility consists of a 400-MeV injector linac that delivers 0.5-mA time-averaged current, a synchrotron that accelerates the beam to 2 GeV at a 30-Hz rate, and two neutron-generating target stations. In the second phase, the 2-GeV beam is accelerated to 10 GeV by a larger RCS, increasing the facility beam power to 5 MW.
Date: June 1997
Creator: Cho, Y.; Chae, Y.-C. & Crosbie, E.

1 to 12 GeV/c beam transport for transverse or longitudinally polarized protons

Description: A two-stage beam transport for polarized protons has been constructed and operated at the Argonne ZGS. The first stage delivers vertically polarized protons (N-type) to an elastic scattering polarimeter consisting of a 10 cm long LH/sub 2/ target and two moveable sets of forward and recoil scintillation counters. The unscattered protons transported through the beam's second stage are focused onto the polarized proton target PPT-III; this target utilizes a 2.5 T R and A magnet to produce target polarizations in the horizontal plane, either in the beam direction (L-type) or transverse to it (S-type). The second stage of the beam is equipped with a combination of superconducting solenoids and dipole magnets; thus the beam polarization can also be rotated to point in the L or S direction. The entire system has been operated successfully over the momentum range 1.0 to 11.75 GeV/c with NS, LS, SS, and LL beam target spin directions.
Date: January 1, 1979
Creator: Colton, E.P.

1-watt composite-slab Er:YAG laser. Revision 1

Description: A diode-side-pumped discrete-optic Er{sup 3+} :YAG laser employs pump-light coupling through a sapphire plate diffusion-bonded to the laser slab, removing heat directly at the pump face of the slab instead of requiring conduction through to its far side. This lowers the temperature in the gain region and gives reduced thermal lensing, which produces exceptional beam quality (M{sup 2} {approx} 1.3) at output powers {approx} 0.3 Watt. Powers above 1 Watt have been demonstrated with peak slope efficiencies {approx}20%. The novel architecture is also applicable to other side-pumped lasers.
Date: February 13, 1997
Creator: Page, R. H.; Bartels, R. A.; Beach, R. J.; Sutton, S. B.; Furu, L. H. & LaSala, J. E.

2-1/2-D electromagnetic modeling of nodular defects in high-power multilayer optical coatings

Description: Advances in the design and production of high damage threshold optical coatings for use in mirrors and polarizers have been driven by the design requirements of high-power laser systems such as the proposed 1.8-MJ National Ignition Facility (NIF) and the prototype 12- kJ Beamlet laser system. The present design of the NIF will include 192 polarizers and more than 1100 mirrors. Currently, the material system of choice for high-power multilayer optical coatings with high damage threshold applications near 1.06 {mu}m are e-beam deposited HfO{sub 2}/Si0{sub 2} coatings. However, the optical performance and laser damage thresholds of these coatings are limited by micron-scale defects and insufficient control over layer thickness. In this report, we will discuss the results of our 2-1/2-D finite-element time- domain (FDTD) EM modeling effort for rotationally-symmetric nodular defects in multilayer dielectric HR coatings. We have added a new diagnostic to the 2-1/2-D FDTD EM code, AMOS, that enables us to calculate the peak steady-state electric fields throughout a 2-D planar region containing a 2-D r-z cross-section of the axisymmetric nodular defect and surrounding multilayer dielectric stack. We have also generated a series of design curves to identify the range of loss tangents for Si0{sub 2} and HfO{sub 2} consistent with the experimentally determined power loss of the HR coatings. In addition, we have developed several methods to provide coupling between the EM results and the thermal-mechanical simulation effort.
Date: July 1996
Creator: Molau, N. E.; Brand, H. R.; Kozlowski, M. R. & Shang, C. C.