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The U5. 0 undulator design for the advanced light source at LBL

Description: The U5.0 undulator, currently under design, is the first in a series of insertion devices planned for the Advanced Light Source at LBL. U5.0 parameters include a 5 cm period, 5 m length with a 0.837 T maximum field at a 14 mm gap. A hybrid configuration utilizing Nd-Fe-B permanent magnet material and Vanadium Permendur poles is used for the magnetic structure. Construction is modular with many pole assemblies attached to a pole mount, which in turn is fastened onto one of the backing beams. Ver… more
Date: August 1, 1989
Creator: Hoyer, E.; Chin, J.; Halbach, K.; Hassenzahl, W.; Humphries, D.; Kincaid, B. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The collaborative program of research in engineering sciences

Description: Research programs in the following areas are briefly described: High-Temperature Gas-Particle Reactions; Mathematical Modelling of Plasma Systems; Metal Transfer in Gas Metal-Arc Welding; Multivariable Control of Gas Metal-Arc Welding; Synthesis of Heat and Work Integration Systems for Chemical Process Plants; Parity Simulation of Dynamic Processes; Fundamentals of Elastic-Plastic Fracture: Three-Dimensional and Mechanistic Modelling; and Comminution of Energy Materials. Publications from each … more
Date: August 1, 1989
Creator: White, D.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Production and decay of heavy top quarks

Description: Experimental evidence indicates that the top quark exists and has a mass between 50 and 200 GeV/c{sup 2}. The decays of a top quark with a mass in this range are studied with emphasis placed on the mass region near the threshold for production of real W bosons. Topics discussed are: (1) possible enhancement of strange quark production when M{sub W} + m{sub s} < m{sub t} < M{sub W} + m{sub b}; (2) exclusive decays of T mesons to B and B{asterisk} mesons using the non-relativistic quark model; (3… more
Date: August 1, 1989
Creator: Kauffman, R.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Multilayer optical elements for generation and analysis of circularly polarized x-rays

Description: Calculations of the relative phase changes of {sigma} and {pi} electric field components on Bragg reflection from and transmission through multilayers are presented. Large relative phase changes can be calculated in certain cases, which may lead to utility of multilayers as quarter-wave plates for generation and analysis of circularly polarized soft x-radiation. Similar behavior may be expected for perfect crystals in the hard x-ray range. 24 refs., 4 figs.
Date: August 1, 1989
Creator: Kortright, J.B. & Underwood, J.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Raman microprobe investigation of molecular structure and organization in the native state of woody tissue

Description: Although the primary emphasis of our program has remained with the application of Raman spectroscopy to the study of native tissue, the scope of the work has been expanded to include a number of complementary approaches. These have included Solid State 13C NMR, autoradiography of radiolabeled woody tissue sections, and the generation of biomimetic tertiary aggregates which simulate states of aggregation characteristic of cell walls. Our Raman spectroscopic studies have resulted in progress in t… more
Date: August 1, 1989
Creator: Atalla, R.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An assessment of the effects of radiation on permanent magnet material in the ALS (Advanced Light Source) insertion devices

Description: Electrons that are lost from the beam during normal operation of a synchrotron radiation source and during a beam dump at the end of a run produce both ionizing radiation and neutrons. This radiation has the potential for damaging sensitive materials, in particular those that need to be very close to the beam. The wigglers and undulators for the Advanced Light Source (ALS) at LBL will use magnetic materials such as the very high performance neodymium-iron-boron, which will be as close as 1 cm a… more
Date: August 1, 1989
Creator: Hassenzahl, W. V.; Jenkins, T. M.; Namito, Y.; Nelson, W. R. & Swanson, W. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Cycle-life improvement of Zn/NiOOH cells by the addition of Ca(OH) sub 2 to the zinc electrode

Description: The addition of Ca(OH){sub 2} to the zinc electrode of Zn/NiOOH cells was investigated in order to determine its effect on reducing the rate of Zinc redistribution. Cells containing 0, 10, 25, and 40 mol% Ca(OH){sub 2} in the zinc electrode were constructed and tested. Ca(OH){sub 2} was found to form a calcium zincate complex with the zincate-supersaturated KOH solution created during the discharge half-cycle. As Ca(OH){sub 2} is insoluble in the electrolyte, the formation of this complex (cont… more
Date: August 1, 1989
Creator: Jain, R.; McLarnon, F. R. & Cairns, E. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cosmic ray half life of sup 54 Mn

Description: A search for the {beta}{sup +} decay of {sup 54}Mn has established an upper limit of 4.4 {times} 10{sup {minus}8} for this branching ratio, and a lower limit of 13.3 for the log ft value for this second forbidden unique transition. Assuming that the {beta}{sup {minus}} decay branch has the same log ft value, then its partial half life must be greater than 4 {times} 10{sup 4} years. Experiments to directly measure the {beta}{sup {minus}} decay rate of {sup 54}Mn are now in progress. 6 refs., 2 f… more
Date: August 1, 1989
Creator: Norman, E.B.; Sur, B.; Vogel, K.R.; Lesko, K.T.; Larimer, R.M. & Browne, E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The digital data acquisition chain and the cosmic ray trigger system for the SLD Warm Iron Calorimeter

Description: The entire data-acquisition chain, from the custom-made front-end electronics to the Fastbus readout and data-reduction module, for the digital readout of the SLD limited streamer tube Warm Iron Calorimeter and Muon Identifier is described. Also described is a Fastbus Cosmic Logic Unit being developed to achieve the capability of reading cosmic ray events, also during the inter-crossing time, for apparatus monitoring and calibration purposes. 9 refs., 9 figs.
Date: August 1, 1989
Creator: Benvenuti, A.; Piemontese, L.; Calcaterra, A.; De Sangro, R.; De Simone, P.; Burrows, P. N. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Grazing-incidence Cerenkov x-ray generation

Description: X-ray Cerenkov radiation can be generated by electrons incident on thin foils. For grazing incidence the Cerenkov radiation intensity can be more than a decade greater than for perpendicular incidence. Experimental results are discussed in terms of a simple formalism. 17 refs., 3 figs.
Date: August 1, 1989
Creator: Moran, Michael J.; Chang, Britton; Schneider, Marilyn B. & Maruyama, Xavier K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A database of fragmentation cross section measurements applicable to cosmic ray propagation calculations

Description: A database of single particle inclusive fragment production cross section measurements has been established and is accessible over common computer networks. These measurements have been obtained from both published literature and direct communication with experimenters and include cross sections for nuclear beams on H, He, and heavier targets, and for H and He beams on nuclear targets, for energies >30 MeV/nucleon. These cross sections are directly applicable to calculations involving cosmic ra… more
Date: August 1, 1989
Creator: Crawford, H. J.; Engelage, J.; Jones, F. C.; Guzik, T. G.; Mitchell, J. W.; Wefel, J. P. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Challenges for utilization of the new synchrotron facilities

Description: The emergence of third generation synchrotron radiation facilities provides new scientific opportunities and challenges. Optimized for small phase space electron beams, long periodic magnet structures, and dedicated scientific user access -- these new machines promise significant increases in spectral brightness, as well as enhanced spatial and temporal coherence properties, which translates to new opportunities for combining high spatial and spectral resolution. The challenges to the machine b… more
Date: August 1, 1989
Creator: Attwood, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Exotic signatures from supersymmetry

Description: Minor changes to the standard supersymmetric model, such as soft flavor violation and R parity violation, cause large changes in the signatures. The origin of these changes and the resulting signatures are discussed. 15 refs., 7 figs., 2 tabs.
Date: August 1, 1989
Creator: Hall, L. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electrical Resistivity of Strongly Coupled Plasmas in Intense Fields

Description: It is now possible to measure the electrical resistivity, or alternatively the electron collision frequency, in strongly coupled plasmas through the use of very fast laser pulses. In such experiments, the effect of the intense laser field needs to be included in the calculation of material transport coefficients. We derive a form for the electrical resistivity which includes the effects of strong correlations, as well as an external electric field. Our results are compared with other theories a… more
Date: August 1, 1989
Creator: Cauble, R.; Rogers, F.J. (Lawrence Livermore National Lab., CA (USA)) & Rozmus, Wojtek (Alberta Univ., Edmonton, AB (Canada). Theoretical Physics Inst.)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Calculation of magnetic error fields in hybrid insertion devices

Description: The Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory requires insertion devices with fields sufficiently accurate to take advantage of the small emittance of the ALS electron beam. To maintain the spectral performance of the synchrotron radiation and to limit steering effects on the electron beam these errors must be smaller than 0.25%. This paper develops a procedure for calculating the steering error due to misalignment of the easy axis of the permanent magnet material. The pro… more
Date: August 1, 1989
Creator: Savoy, R.; Halbach, K.; Hassenzahl, W.; Hoyer, E.; Humphries, D. & Kincaid, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Weighted fit of parametric functions to distributions: The new interface of HOBOOK with MINUIT

Description: The fitting routines of the HBOOK package allow weighted fit of parametric functions to the contents of a one, two or N-dimensional distribution, and analysis of the function in the neighborhood of its minimum, through an interface with the MINUIT package. These routines have been rewritten so as to interface the new version of MINUIT and to allow for smooth transitions to future versions of both packages. We discuss the interface and its capabilities: it is more stable than the previous versio… more
Date: August 1, 1989
Creator: Lessner, E.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The challenges of third-generation synchrotron light source

Description: Third-generation synchrotron light sources are specifically designed to operate with long insertion devices that produce very high brightness beams of synchrotron radiation. There are many such facilities now under construction, or in the design stage, all over the world. After a brief review of the main properties of the low emittance storage rings that form the heart of these facilities, we will discuss the particular challenges that accompany their design. These include: the effects of the s… more
Date: August 1, 1989
Creator: Jackson, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Study of four-lepton final states in electron-positron interactions at 29 GeV

Description: This thesis presents a study of electron-positron scattering to four light leptons. The motivations behind it are twofold. Firstly, the study is a test of the theory of electron-positron interactions to 4th order in the fine structure constant {alpha}. A deviation from the theory could indicate the existence of a heavy new particle. Secondly, a measurement of these processes may prove useful in the understanding of other QED-type reactions. The method for simulating the four-lepton processes by… more
Date: August 1, 1989
Creator: Petradza, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cosmic ray half life of sup 56 Ni

Description: A search for the {beta}{plus} decay of {sup 56}Ni has established an upper limit on the branching ratio of 7.2 {times} 10{sup {minus} 7} for the most likely such transition. This provides a lower limit of 2.3 {times} 10{sup 4} years for the cosmic ray half life of {sup 56}Ni. 2 refs., 2 figs.
Date: August 1, 1989
Creator: Norman, E.B.; Sur, B.; Lesko, K.T.; Larimer, R.M. & Browne, E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Quantum mechanical reactive scattering theory for simple chemical reactions: Recent developments in methodology and applications

Description: It has recently been discovered that the S-matrix version of the Kohn variational principle is free of the Kohn anomalies'' that have plagued other versions and prevented its general use. This has made a major contribution to heavy particle reactive (and also to electron-atom/molecule) scattering which involve non-local (i.e., exchange) interactions that prevent solution of the coupled channel equations by propagation methods. This paper reviews the methodology briefly and presents a sample of … more
Date: August 1, 1989
Creator: Miller, William H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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SLC status and SLAC (Stanford Linear Accelerator Center) future plans

Description: In this presentation, I shall discuss the linear collider program at the Stanford Linear Accelerator Center as it is now, and as we hope to see it evolve over the next few years. Of greatest interest to the high energy accelerator physics community gathered here is the development of the linear collider concept, and so I shall concentrate most of this paper on a discussion of the present status and future evolution of the SLC. I will also briefly discuss the research and development program tha… more
Date: August 1, 1989
Creator: Richter, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High Resolution-Angle Resolved Photoemission Studies of High Temperature Superconductors

Description: Recent photoemission studies of Y 123 and Bi 2212 performed with high energy and angular resolution have provided detailed information on the nature of the states near the Fermi level. Measurements of the superconducting gap, band dispersion, and the density of states near the Fermi level in the normal state all support a Fermi liquid description of these materials. 5 refs., 4 figs.
Date: August 1, 1989
Creator: Olson, C. G.; Liu, R.; Lynch, D. W.; Veal, B. W.; Chang, Y. C.; Jiang, P. Z. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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An immersed field cluster klystron

Description: Future linear colliders have a need for high power, high frequency, and short-pulse radio frequency sources. The proposed ''cluster klystron'' should give over 1 GW of 12 GHz radio frequency power, can employ direct current or a long high-voltage pulse, but can be gated to give pulses down to a few tens of nanoseconds. The device consists of 42 parallel 100 A channels. Each channel is fed from an individual magnetron-type gun employing a common 50 kV mod-anode. The beams are accelerated to 400 … more
Date: August 1, 1989
Creator: Palmer, R. B.; Herrmannsfeldt, W. B. & Eppley, K. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Multiple-neutral-meson decays of the /tau/ lepton and electromagnetic calorimeter requirements at Tau-Charm Factory

Description: This is a study of the physics sensitivity to the multiple-neutral-meson decays of the /tau/ lepton at the Tau-Charm Factory. The sensitivity is compared for a moderate and an ultimate electromagnetic calorimeter. With the high luminosity of the Tau- Charm Factory, a very large sample of the decays /tau//sup /minus// /yields/ /pi//sup /minus//2/pi//sup 0//nu//sub /tau// and /tau//sup /minus// /yields/ /pi//sup /minus//3/pi//sup 0//nu//sub /tau// can be collected with both detectors. However, wi… more
Date: August 1, 1989
Creator: Gan, K.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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