Electron positron factories (open access)

Electron positron factories

In this paper, we will first indicate the key issues in designing a B-factory and a {phi}-factory, and illustrate the approaches that are being followed to address them. In general, reaching the B-factory parameter regime offers the most challenges, so we will emphasize it here. Then we will consider an extrapolation of our present understanding of collider performance and assess the maximum luminosity that could be anticipated. To reach extremely high luminosity, it may be necessary to consider possibilities beyond the scope of standard'' approaches to collider design; a few illustrative examples are outlined. For both the present designs and the extrapolated parameters, R D activities in a few key areas are required; these areas are discussed in this paper also.
Date: December 1, 1990
Creator: Zisman, M. S.; Chattopadhyay, S.; Garren, A. A.; Lambertson, G. (Lawrence Berkeley Lab., CA (United States)); Bloom, E.; Corbett, W. J. et al.
System: The UNT Digital Library
An introduction to baryon violation in standard electroweak theory (open access)

An introduction to baryon violation in standard electroweak theory

I shall begin with a qualitative overview of the anomaly and B violation at zero and non-zero temperature, demonstrating how these processes may be understood on the back of an envelope. Then I shall discuss a part of the formalism necessary for doing calculations in more detail. Specifically, B violation is related to various solutions to the Euclidean equations of motion; instantons, sphalerons, and calorons (also called periodic instantons). The applicability of the various solutions may be understood by analogies with elementary quantum mechanics problems. Finally, I shall touch upon the computation of high-energy B violation mentioned above. 29 refs., 11 figs.
Date: December 1, 1990
Creator: Arnold, P.B.
System: The UNT Digital Library
A new experimental limit on the electric dipole moment of the electron (open access)

A new experimental limit on the electric dipole moment of the electron

We describe a search for the electric dipole moment d{sub e} of the electron, carried out with {sup 205}Tl atoms in the ground state. The experiment makes use of the separated-oscillating-field magnetic-resonance method, laser state selection, fluorescence detection, and two counter-propagating atomic beams. Very careful attention is paid to systematic effects. The result for the atomic electric dipole moment is d{sub a} = (1.6 {plus minus} 5.0) {times} 10{sup {minus}24} e cm. If we assume the theoretical ratio d{sub a}/d{sub e} = {minus}600, this yields d{sub e} = ({minus}2.7 {plus minus} 8.3) {times} 10{sup {minus}27} e cm. 17 refs., 7 figs., 1 tab.
Date: December 1, 1990
Creator: Carlberg, C.; Gould, H. (Lawrence Berkeley Lab., CA (USA)); Abdullah, K.; Commins, E.D. & Ross, S.B. (Lawrence Berkeley Lab., CA (USA) California Univ., Berkeley, CA (USA). Dept. of Physics)
System: The UNT Digital Library
Framework ordering in aluminophosphate molecular sieves studied by sup 27 Al double rotation NMR (open access)

Framework ordering in aluminophosphate molecular sieves studied by sup 27 Al double rotation NMR

Aluminum-27 Double Rotation NMR spectroscopy (DOR) has been used to investigate framework ordering in the aluminophosphate molecular sieves VPI-5, AlPO{sub 4}-5, and AlPO{sub 4}-8. Well resolved peaks in the {sup 27}Al DOR spectra of both hydrated and dehydrated VPI-5 allow isotropic shifts to be correlated with local framework structure. more distorted aluminum environments are reflected by broader lines in {sup 27}Al DOR spectra of AlPO{sub 4}-5 and AlPO{sub 4}-8.
Date: December 1, 1990
Creator: Chmelka, B.F.; Wu, Y.; Jelinek, R.; Davis, M.E. & Pines, A. (Lawrence Berkeley Lab., CA (USA) California Univ., Berkeley, CA (USA). Dept. of Chemistry)
System: The UNT Digital Library
An electro-optical imaging approach to the prompt signal processing problem of mega-channel SSC detector arrays (open access)

An electro-optical imaging approach to the prompt signal processing problem of mega-channel SSC detector arrays

The physics demands of high luminosity at the SSC and the sometimes subtle measurements required to elucidate new physics will undoubtedly tax existing instrumentation. As is the case with most experimental fields, new physics follows from better measurement concepts and technologies. We expect this to be the case with the SSC as well. In what follows, we offer a glimpse of what may be possible using some of the recent results from the emerging technologies in the field of electro-optics. 12 refs., 4 figs.
Date: December 1, 1990
Creator: Lowry, M.; Ables, E.; Bionta, R.; Haigh, R.; Hugenberg, K.; Kalibjian, R. et al.
System: The UNT Digital Library
HOM (higher order mode) losses at the Interaction Region of the B factory (open access)

HOM (higher order mode) losses at the Interaction Region of the B factory

Masking at the Interaction Region (IR) will presumably reduce the synchrotron radiation background in the detector. One possible layout of the IR for the B factory, shows a rather complicated system of masks. A bunch passing each mask will generate RF waves. These waves (usually called higher order modes, HOMs) will be absorbed in the beam pipe wall producing additional heating and, interacting with the beam, kicking particles in the radial and azimuthal directions. This may change the bunch motion and its emittance. These effects are estimated in the present note. 4 refs., 3 figs., 3 tabs.
Date: December 1, 1990
Creator: Heifets, S.
System: The UNT Digital Library
Calculation of defect properties of NiTi and FeTi (open access)

Calculation of defect properties of NiTi and FeTi

The energies and configurations of interstitials and vacancies in the B2 ordered compounds NiTi and FeTi were calculated using atomistic simulation. The stable configuration of a vacancy after the removal of an Ni atom was a vacant Ni site; similarly, the removal of an Fe atom in FeTi resulted in a vacant Fe site. Removal of a Ti atom in both compounds, however, resulted in a vacant Ni or Fe site and an adjacent antisite defect. The effective vacancy formation energies in NiTi and FeTi were calculated to be 1.48 and 1.07 eV, respectively. Interstitials in NiTi formed split {l angle}111{r angle} configurations consisting of a Ni-Ni dumbbell oriented in the {l angle}111{r angle} direction with one or two adjacent antisite defects. The Fe interstitial in FeTi had a similar configuration, except the dumbbell contained Fe atoms. The Ti interstitial in FeTi formed an {l angle}110{r angle} Fe-Fe dumbbell. 8 refs., 2 tabs.
Date: December 1, 1990
Creator: Lutton, R.T.; Sabochick, M.J. (Air Force Inst. of Tech., Wright-Patterson AFB, OH (USA). Dept. of Engineering Physics) & Lam, N.Q. (Argonne National Lab., IL (USA))
System: The UNT Digital Library
Electro-optic transient imaging instrumentation development at Lawrence Livermore National Laboratory: Implications for SSC instrumentation development (open access)

Electro-optic transient imaging instrumentation development at Lawrence Livermore National Laboratory: Implications for SSC instrumentation development

Over the last decade, the underground weapons physics laboratories fielded by LLNL's Nuclear Test and Experimental Sciences (NTES) program have experienced marked change. This change is characterized by a phenomenal growth in the amount of data returned per event. These techniques have been developed as a result of the severe demands placed upon transient instrumentation by the physics requirements of our underground nuclear laboratories. The detector front-ends must quickly detect, process and transmit a large volume of data to recording stations located approximately 1 km from the event. In a recent event, the detector front-ends successfully handled data at a prompt rate of approximately 13 Terabits/sec. Largely, this advance can be attributed directly to the increased use of electro-optic techniques. These highly-parallel high-bandwidth imaging instrumentation systems developed for the test program may have a lot to offer the high-energy physics community tackling the challenge of the unprecedented luminosity and fidelity demands at the SSC. In what follows, we discuss details of a few of our prompt instrumentation techniques and compare these capabilities to the detector requirements for the challenging physics at the SSC. 5 refs., 3 figs.
Date: December 1, 1990
Creator: Lowry, M.; Jacoby, B. & Schulte, H.
System: The UNT Digital Library
XRD (x-ray diffraction) and HREM (high resolution electron microscopy) studies of nanocrystalline Cu and Pd (open access)

XRD (x-ray diffraction) and HREM (high resolution electron microscopy) studies of nanocrystalline Cu and Pd

Consolidated powders of nanocrystalline Cu and Pd have been studied by x-ray diffraction (XRD) and high resolution electron microscopy (HREM) as part of an investigation of the mechanical behavior of nanocrystalline pure metals. XRD line broadening measurements were made to estimate grain size, qualitative grain size distribution and average long range strains in a number of samples. Mean grain sizes range from 4--60 nm and have qualitatively narrow grain size distributions. Long range lattice strains are of the order of 0.2--3% in consolidated samples. These strains apparently persist and even increase in Cu samples after annealing at 0.35 Tm (498K) for 2h, accompanied by an apparent increase in grain size of {ge}2x. Grain size, grain size distribution width and internal strains vary somewhat among samples produced under apparently identical processing conditions. HREM studies show that twins, stacking faults and low-index facets are abundant in as-consolidated nanocrystalline Cu samples. Methodology, results, and analysis of XRD and HREM experiments are presented. 17 refs., 2 figs., 2 tabs.
Date: December 1, 1990
Creator: Nieman, G. W.; Weertman, J. R. (Northwestern Univ., Evanston, IL (USA). Dept. of Materials Science and Engineering) & Siegel, R. W. (Argonne National Lab., IL (USA))
System: The UNT Digital Library
Electron trapping in amorphous silicon: A quantum molecular dynamics study (open access)

Electron trapping in amorphous silicon: A quantum molecular dynamics study

Quantum molecular dynamics (QMD) simulations provide the real-time dynamics of electrons and ions through numerical solutions of the time-dependent Schrodinger and Newton equations, respectively. Using the QMD approach we have investigated the localization behavior of an excess electron in amorphous silicon at finite temperatures. For time scales on the order of a few picoseconds, we find the excess electron is localized inside a void of radius {approximately}3 {Angstrom} at finite temperatures. 12 refs.
Date: December 1, 1990
Creator: Yang, Lin H.; Kalia, R.K. & Vashishta, P.
System: The UNT Digital Library
A compilation of jet finding algorithms (open access)

A compilation of jet finding algorithms

Technical descriptions of jet finding algorithms currently in use in p{bar p} collider experiments (CDF, UA1, UA2), e{sup +}e{sup {minus}} experiments and Monte-Carlo event generators (LUND programs, ISAJET) have been collected. 20 refs.
Date: December 1, 1990
Creator: Flaugher, B. (Fermi National Accelerator Lab., Batavia, IL (USA)) & Meier, K. (Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany, F.R.))
System: The UNT Digital Library
A visual inspection system for evaluating the interior surface of valve stems on material storage container tops (open access)

A visual inspection system for evaluating the interior surface of valve stems on material storage container tops

A nondestructive inspection for evaluating the interior surface of the small diameter valve stems on material storage container tops was mandated. The specifications required that the interior surface of the valve stem have a surface finish of {number sign}16 or better. Conventional methods which utilizes mechanical stylus-type''surface analyzing equipment could not extend into the narrow 0.312 inch diameter by 1.5 inch deep hole (of the valve stem). A visual inspection system which exploits the capabilities of a high resolution fiberoptic borescope was designed and assembled to resolve this requirement. This paper discusses the design and inspection features of the aforementioned system and includes several illustrations of inspection results. 6 figs.
Date: December 1, 1990
Creator: Pickett, C.A.
System: The UNT Digital Library
Theoretical topics in B-physics (open access)

Theoretical topics in B-physics

The bottom quark should need no introduction. Other than the undiscovered top quark, it is by far the most fashionable of the six. There is good reason for this. It is bottom-quark behavior which holds out the most hope of measuring and understanding some of the most hope of measuring and understanding some of the most fundamental and delicate parameters of the standard model -- those having to do with the origin of electroweak mixing -- and thereby in all probability also the origin of quark mass. Also interwoven into this is the subject of CP violation, and its proposed interpretation in terms of electroweak mixing. In this section we shall review the basics of electroweak mixing and how it is impacted by the study of b-quark properties. There are by now many lecture series and workshop proceedings devoted to this topic, so I will not try to be comprehensive, but only hit some highlights. 28 refs., 14 figs., 4 tabs.
Date: December 1, 1990
Creator: Bjorken, J. D.
System: The UNT Digital Library
An operational description of the compact and tunable LEP spin rotator (open access)

An operational description of the compact and tunable LEP spin rotator

Special configurations of horizontal and vertical bending magnets can rotate the spin vector from the vertical to the longitudinal direction. The compact and tunable LEP spin rotator discovered recently fits neatly into the list of such configurations that generate a group of 24 rotation operators. It is shown that any of these configurations can be achieved with a string of 8 simple dipoles. Results can, in principle, be applied to electron or proton beams. 3 refs., 2 figs., 2 tabs.
Date: December 1, 1990
Creator: Fieguth, T. (Stanford Linear Accelerator Center, Menlo Park, CA (USA)) & Guignard, G. (European Organization for Nuclear Research, Geneva (Switzerland))
System: The UNT Digital Library
Coherent x-ray lasers for applications (open access)

Coherent x-ray lasers for applications

Many of the projected applications of x-ray lasers require high quality output radiation with properties such as short wavelength, high power, good focusability, short pulse, and high degree of coherence. We discuss the requirements of an x-ray laser for the application of holography of biological samples. We present ideas for achieving these properties. Given that population inversions can be established to provide laser gain, we discuss how the propagation and amplification of x-rays within the lasing medium affect the quality of the output radiation. Particular attention is given toward the development of transverse coherence. Results are presented from several methods for calculating the coherence, including a modal analysis and a numerical-wave propagation code. Calculations of the expected degree of coherence of standard x-ray lasers are given, as well as designs for more coherent lasers. 9 refs., 6 figs., 1 tab.
Date: December 1, 1990
Creator: London, R. A.; Amendt, P.; Rosen, M. D.; Feit, M. D.; Fleck, J. A. (Lawrence Livermore National Lab., CA (USA)) & Strauss, M. (Negev Nuclear Research Centre, Beersheba (Israel))
System: The UNT Digital Library
Strangeness production in nucleus-nucleus collisions: An experimental review (open access)

Strangeness production in nucleus-nucleus collisions: An experimental review

In experiments with oxygen (60 and 200 GeV/N) and sulphur (200 GeV/N) ions at CERNSPS, large energy densities of the order of 2--3 GeV/fm{sub 3} have been observed, which according to QCD calculations, satisfy necessary conditions for the formation of a quark gluon plasma (QGP) phase. Under such conditions, colour would no longer be confined to hadronic dimensions, and quarks and gluons will propagate freely throughout an extended volume. Somehow lower energy densities, of the order of 0.7--1 GeV/fm{sub 3}, were observed in AGS experiments with 15 GeV/N silicon beams and heavy targets. These energy densities might be adequate for investigations of the pre-equilibrium stage, during which the momentum space distribution has been degradated from its initial value but is not yet thermal. First experimental results, available now, show promise of seeing signs of a new phase of matter. In this review the current status of the selective experimental results on strange-particle production, which are relevant to equilibration and QGP formation in nucleus-nucleus collisions, is presented.
Date: December 1, 1990
Creator: Odyniec, G.
System: The UNT Digital Library
A tritium target system for. mu. CF (open access)

A tritium target system for. mu. CF

An apparatus has been constructed for the safe handling of tritium as part of a series of muon-catalyzed fusion experiments. The equipment was designed to handle 100 kCi of tritium. The main parts of this system are the oil-free high vacuum and transfer system, and the quadrupole mass analyzer for a direct determination of the target content. The system was used successfully for five continuous periods of operation of over one month each. A new target system was constructed at Lawrence Livermore National Laboratory (LLNL) for ultimate use at Paul Scherrer Institute (PSI) to investigate the high temperature and high pressure region. 9 refs., 4 figs.
Date: December 1, 1990
Creator: Zmeskal, J.; Ackerbauer, P. (Oesterreichische Akademie der Wissenschaften, Vienna (Austria). Inst. fuer Mittelenergiephysik); Sherman, R.H. (Los Alamos National Lab., NM (USA)); Durham, W.B.; Heard, H.C. (Lawrence Livermore National Lab., CA (USA)); Neumann, W. (Eidgenoessische Technische Hochschule, Zurich (Switzerland)) et al.
System: The UNT Digital Library
Interactions of energetic particles and clusters with solids (open access)

Interactions of energetic particles and clusters with solids

Ion beams are being applied for surface modifications of materials in a variety of different ways: ion implantation, ion beam mixing, sputtering, and particle or cluster beam-assisted deposition. Fundamental to all of these processes is the deposition of a large amount of energy, generally some keV's, in a localized area. This can lead to the production of defects, atomic mixing, disordering and in some cases, amorphization. Recent results of molecular dynamics computer simulations of energetic displacement cascades in Cu and Ni with energies up to 5 keV suggest that thermal spikes play an important role in these processes. Specifically, it will be shown that many aspects of defect production, atomic mixing and cascade collapse'' can be understood as a consequence of local melting of the cascade core. Included in this discussion will be the possible role of electron-phonon coupling in thermal spike dynamics. The interaction of energetic clusters of atoms with solid surfaces has also been studied by molecular dynamics simulations. this process is of interest because a large amount of energy can be deposited in a small region and possibly without creating point defects in the substrate or implanting cluster atoms. The simulations reveal that the dynamics of the …
Date: December 1, 1990
Creator: Averback, R.S.; Hsieh, Horngming (Illinois Univ., Urbana, IL (USA). Dept. of Materials Science and Engineering); Diaz de la Rubia, T. (Lawrence Livermore National Lab., CA (USA)) & Benedek, R. (Argonne National Lab., IL (USA))
System: The UNT Digital Library
Adaptation of the IBM ECR (electric cantilever robot) robot to plutonium processing applications (open access)

Adaptation of the IBM ECR (electric cantilever robot) robot to plutonium processing applications

The changing regulatory climate in the US is adding increasing incentive to reduce operator dose and TRU waste for DOE plutonium processing operations. To help achieve that goal the authors have begun adapting a small commercial overhead gantry robot, the IBM electric cantilever robot (ECR), to plutonium processing applications. Steps are being taken to harden this robot to withstand the dry, often abrasive, environment within a plutonium glove box and to protect the electronic components against alpha radiation. A mock-up processing system for the reduction of the oxide to a metal was prepared and successfully demonstrated. Design of a working prototype is now underway using the results of this mock-up study. 7 figs., 4 tabs.
Date: December 1, 1990
Creator: Armantrout, G. A.; Pedrotti, L. R. (Lawrence Livermore National Lab., CA (USA)); Halter, E. A. & Crossfield, M. (International Business Machines Corp., Armonk, NY (USA))
System: The UNT Digital Library
The Soudan 2 honeycomb calorimeter (open access)

The Soudan 2 honeycomb calorimeter

Soudan 2 is an 1100-ton honeycomb tracking calorimeter which is being constructed to search for nucleon decay. The detector consists of finely segmented iron instrumented with long drift tubes, and records three spatial coordinates and dE/dx for every gas crossing. Excellent event reconstruction capability, particle identification and muon sign and direction determination give superior rejection of the neutrino background to nucleon decay in many modes. The first 620 tons of Soudan 2 are now in steady operation, with completion planned for 1992. Detector performance has been studied using cosmic ray tracks and a charged test beam calibration. Results on detector performance and detector response are described in this paper. 2 refs. , 11 figs.
Date: December 1, 1990
Creator: Garcia-Garcia, C.
System: The UNT Digital Library
Environmentally assisted cracking in light water reactors (open access)

Environmentally assisted cracking in light water reactors

Topics that have been investigated during this year include (1) SCC of A533-Gr B steel used in steam generator and reactor pressure vessels, (2) fatigue of Type 316NG SS, and (3) SCC of Type 347 and CF-3 cast duplex stainless steels in simulated BWR water. Crack-growth-rate (CGR) tests were performed on a composite A533-Gr B/Inconel-182 specimen in which the stress corrosion crack in the Inconel-182 weld metal penetrated and grew into the A533-Gr B steel. CGR tests were also conducted on conventional (unplated) and nickel- or gold-plated A533-Gr B specimens to provide insight into whether the nature of the surface layer on the low-alloy steel, either oxide corrosion products or a noble metal, influences the overall SCC process. CGR data on the A533-Gr B specimens were compared with the fatigue crack reference curves in the ASME Boiler and Pressure Vessel Code, Section XI, Appendix A. Fatigue tests were conducted on Type 316NG SS in air and simulated BWR water at low strain ranges and frequencies to better establish margins in the ASME Code Section III Fatigue Design Curves. CGR tests were also conducted on specimens of Type 347 SS with different heat-treatment conditions, and a specimen of CF-3 cast stainless …
Date: December 1, 1990
Creator: Park, J.Y.; Ruther, W.E.; Kassner, T.F. & Shack, W.J.
System: The UNT Digital Library
Texture and microstructure development in Al-2%Mg during high- temperature deformation (open access)

Texture and microstructure development in Al-2%Mg during high- temperature deformation

The high rate sensitivity of the flow stress that is exhibited by alloys under solute drag control, such as Al-Mg at high temperatures, influences texture development because more slip systems contribute to deformation. Al-2% Mg was tested in channel-die compression, i.e. idealized rolling, at 290{degree}C and 400{degree}C, at strain rates from 10{sup {minus}1}/s to 10{sup {minus}5}/s. The texture development in rolling predicted by polycrystal plasticity simulation indicates that the brass component increases while the copper component decreases when the rate sensitivity is raised. The experimental results are in good agreement with this prediction. In addition, cube component appears when microstructural change occurs due to dynamic recrystallization. This microstructural change leads to the shift from {l angle}011{r angle} to {l angle}001{r angle} fiber texture in free compression at high temperature. 18 refs., 13 figs.
Date: December 1, 1990
Creator: Chen, S.R. & Kocks, U.F.
System: The UNT Digital Library
Recent results on CP-violation from Fermilab experiment E731 (open access)

Recent results on CP-violation from Fermilab experiment E731

We report the current status of the analysis for the CP-violation parameters, {var epsilon}{prime}/{var epsilon}, from the entire data sample of Fermilab experiment E731. A new measurement of the CP-violation parameter {eta}{sub {plus minus}{gamma}} was extracted from the K{sub L} {minus} K{sub S} interference of the {pi}{sup +}{pi}{sup {minus}}{gamma} decay mode downstream of a regenerator. The preliminary result, {vert bar}{eta}{sub {plus minus}{gamma}}{vert bar} = 0.0020 {plus minus} 0.0002(stat) {plus minus} 0.0003(syst), is consistent with {vert bar}{eta}{sub {plus minus}}{vert bar} from {pi}{sup +}{pi}{sup {minus}} decay mode. Some results on the measurements of the branching ratio for K{sub L} {yields} {pi}{sup +}{pi}{sup {minus}}{gamma} and K{sub S} {yields} {pi}{sup +}{pi}{sup {minus}}{gamma} are presented here. For the very first time, the quadratic decay parameter of K{sub L} {yields} 3{pi}{sup 0} has been measured from the 3{pi}{sup 0} Dalitz plot. Our result, b = ({minus}0.6 {plus minus} 1.4) {times} 10{sup {minus}3}, is consistent with zero, indicating a flat Dalitz distribution. It is inconsistent with the fitted result, b = ({minus}8.3 {plus minus} 2.4) {times} 10{sup {minus}3}, from Devlin and Dickey's review. 13 refs., 5 figs.
Date: December 1, 1990
Creator: Hsiung, Yee B.
System: The UNT Digital Library
Problems underlying the use of referential integrity mechanisms in relational database management systems (open access)

Problems underlying the use of referential integrity mechanisms in relational database management systems

Referential integrity is used in relational data-bases for expressing existence dependencies between tuples. Relational database management systems (RDBMS) provide diverse referential integrity capabilities. Thus, is some RDBMSs referential integrity constraints can be specified non-procedurally (declaratively), while in other RDBMSs they must be specified procedurally. Moreover, some RDBMSs restrict the class of allowed referential integrity constraints. We examine in this paper the main problems underlying the use of referential integrity mechanisms in three representative RDBMSs, DB2, SYBASE, and INGRES. 11 refs.
Date: December 1, 1990
Creator: Markowitz, V.M.
System: The UNT Digital Library