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The Low-Energy State ofCirculating Stored Ion Beams: Crystalline Beams

Description: Molecular dynamics is employed to study the low energy states of a beam of charged particles subject to circumferentially varying guiding and focusing forces and with Coulomb forces between the particles. In a constant gradient ring, the lowest energy state is never ordered, but in an alternating gradient structure, operating below the transition energy, the lowest state is ordered. The nature and characteristics of the ground state depends upon the beam density and the ring parameters. For zero temperature the crystal remains intact for a very long time, but at nonzero temperatures it gains energy from the lattice. A critical temperature exists above which the crystal melts rapidly.
Date: March 10, 1994
Creator: Wei, J.; Li, X.-P. & Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department

D0 Solenoid Chimney Routing Clearances

Description: This engineering note contains information about the measured clearances along the chimney route from the solenoid to the control dewar. This type of information is best conveyed by sketches and a few photos. Twelve photos taken on 2/17/94 are included which gIVe perspective views along the path. The detector was parked in the collision hall on this date. The CF iron was split open to the east and the South EF iron was rolled back. Also the South EndCap Calorimeter was rolled to the south on this day. This allowed personnel access and the photographic opportunity. A full set of raw dimensional sketches are included. These sketches were generated by me using a 25 foot tape measure and a note pad. The sketches are in chronological order with the most recent on top. The first sketch, 5/18/94, describes the 'tightest' location for the upward incline portion of the chimney. The sketches on 2/14/94 thru 2/16/94 are refinements of the early 1992 and 1993 sketches. They pick out quite a bit more detail of specific detector components along the path. The dimensional sketches of 1992 and 1993 gave information in not as much detail and therefore gave a more constrained clearance description. Most of the information of the early sketches was jotted down on the plan view dated 10-29-92. This sketch also had some information lifted from prints which later was superseded by the 1994 sketches. I tried to label components and give views either titled 'Elevation' or 'Plan' which refers to a top view looking down. Also where I could I jotted down direction, ie. South, East etc. Hopefully with a little effort one can decifer it. The curvature of the CC was determined from a three dimensional topographical survey. This survey information is stored in an electronic drawing file ...
Date: February 23, 1994
Creator: Rucinski, R.
Partner: UNT Libraries Government Documents Department

Optical assessment of large marine particles: development of an imaging and analysis system for quantifying large particle distributions and fluxes. Annual report, 1993-1994

Description: The central goal of DOE`s Ocean Margin Program (OMP) is to determine whether continental shelves are quantitatively significant in removing carbon dioxide from the atmosphere and isolating it via burial in sediments or exporting it to the open ocean (Program Announcement, 1991). A major component of the OMP will be to measure carbon flux on the shelf and across the shelf to the slope and open ocean. In the first round of OMP funding we proposed to develop an optical instrument package and the analytical techniques to measure a wide spectrum of the large aggregate population of particles in the shelf/slope environment. This particle population, encompassing the ``marine snow`` size particles (diameters > 0.5 mm), is thought to be the major pathway of material flux in the ocean (McCave, 1975; Asper, 1987; Walsh and Gardner, 1992). The overall objective of this proposal was to develop an instrument package and the analytical techniques to precisely measure a wide spectrum of the large aggregate population of particles in the shelf/slope environment at a rate sufficient to integrate the observed particle distributions into the coupled physical and biogeochemical models necessary to understand the shelf and slope as a system. We envisioned three stages of development of the instrument package: (1) design, assembly, and laboratory testing of all components and the package as a whole, (2) a short period of laboratory and field testing of the instrument package to determine the best operational parameters, and (3) operations within a framework of complementary analytical sampling such as an appropriate process study funded under the OMP. The first two stages were covered by this proposal. A renewal proposal follows to cover the third stage. 6 figs.
Date: December 31, 1994
Creator: Walsh, I. D. & Gardner, W. D.
Partner: UNT Libraries Government Documents Department

Final report from VFL Technologies for the pilot-scale thermal treatment of Lower East Fork Poplar Creek floodplain soils. LEFPC Appendices, Volume 3, Appendix V-B

Description: This report consists of appendix V-B which contains the final verification run data package. Validation of analytical data is presented for Ecotek LSI. Analytical results are included of both soil and creek bed samples for the following contaminants: metals; metals (TCLP); uranium; gross alpha/beta; and polychlorinated biphenyls.
Date: September 1, 1994
Partner: UNT Libraries Government Documents Department

Particle filtration: An analysis using the method of volume averaging

Description: The process of filtration of non-charged, submicron particles is analyzed using the method of volume averaging. The particle continuity equation is represented in terms of the first correction to the Smoluchowski equation that takes into account particle inertia effects for small Stokes numbers. This leads to a cellular efficiency that contains a minimum in the efficiency as a function of the particle size, and this allows us to identify the most penetrating particle size. Comparison of the theory with results from Brownian dynamics indicates that the first correction to the Smoluchowski equation gives reasonable results in terms of both the cellular efficiency and the most penetrating particle size. However, the results for larger particles clearly indicate the need to extend the Smoluchowski equation to include higher order corrections. Comparison of the theory with laboratory experiments, in the absence of adjustable parameters, provides interesting agreement for particle diameters that are equal to or less than the diameter of the most penetrating particle.
Date: December 1, 1994
Creator: Quintard, M. & Whitaker, S.
Partner: UNT Libraries Government Documents Department

The energy spectrometer for particles (ESP): Instrument description and orbital performance

Description: The ESP detector is functionally described, along with the pertinent orbital and spin properties of the spacecraft that supports it. The phoswiched plastic/BGO scintillators sensor design, electronic implementation, and resulting data types are recounted, and the ground calibration procedures are reported. Several illustrative examples of data are given, including the solar proton event of 29 September 1989, and the nearly periodic episodes of high relativistic electron flux that are associated with solar coronal holes which have been a dominant feature of the space weather over the past few years. 2 refs., 10 figs., 1 tab.
Date: December 31, 1994
Creator: Meier, M.M.; Belian, R.D.; Cayton, T.E.; Christensen, R.; Garcia, B.; Grace, K. et al.
Partner: UNT Libraries Government Documents Department

Optical assessment of large marine particles: development of an imaging and analysis sytem for quantifying large particle distributions and fluxes. Annual report, 1992-1993

Description: The central goal of DOE`s Ocean Margin Program (OMP) is to determine whether continental shelves are quantitatively significant in removing carbon dioxide from the atmosphere and isolating it via burial in sediments or exporting it to the open ocean (Program Announcement, 1991). A major component of the OMP will be to measure carbon flux on the shelf and across the shelf to the slope and open ocean. We are developing a video and optical instrument package (LAPS: Large Aggregate Profiling System) and the analytical techniques to precisely measure a wide spectrum of the large aggregate population of particles in the shelf/slope environment. This particle population, encompassing the ``marine snow`` size particles (diameters > 0.5 mm), is thought to be the major pathway of material flux in the ocean (McCave, 1975; Asper, 1987; Walsh and Gardner, 1992). Our goal is to use aggregate abundance and size spectrum data along with the CTD, beam attenuation and fluorescence data collected with our instrument package to collect data rapidly, repeatedly and accurately such that it is both linkable to carbon flux and usable in biophysical models. Additionally, measurements of particle flux will be made with sediment traps deployed on the continental slope in conjunction with the physical oceanography program. The combination of profiles and sections of aggregate data along with the measured mass flux and chemistry from the sediment traps will allow for a robust estimate of the mass transport and flux of organic carbon via the aggregate pathway. The LAPS will be tested in the field area during a cruise in June/July 1994. Sediment traps will also be deployed on that cruise to make the first comparisons between measured flux and aggregate abundance in the field area. Efforts to streamline the image processing have resulted in a suite of programs to handle data ...
Date: May 1, 1994
Creator: Walsh, I. D. & Gardner, W. D.
Partner: UNT Libraries Government Documents Department

Testing of the Eberline PCM-2

Description: The PCM-2 manufactured by Eberline Instruments is a whole body monitor that detects both alpha and beta contamination. The PCM-2 uses an IBM compatible personal computer for all software functions. The PCM-2 has 34 large area detectors which can cover approximately 40% of the body at a time. This requires two counting cycles to cover approximately 80% of the body. With the normal background seen at Rocky Flats, each count time takes approximately 15--20 seconds. There are a number of beta and gamma whole body monitors available from different manufacturers, but an alpha whole body monitor is a rarity. Because of the need for alpha whole body monitors at The Rocky Flats Environmental Technology Site, it was decided to do thorough testing on the PCM-2. A three month test was run in uranium building and a three month test in a plutonium building to verify the alpha capabilities of the PCM-2.
Date: December 23, 1994
Creator: Howe, K.L.
Partner: UNT Libraries Government Documents Department

The uses of electron beam ion traps in the study of highly charged ions

Description: The Electron Beam Ion Trap (EBIT) is a relatively new tool for the study of highly charged ions. Its development has led to a variety of new experimental opportunities; measurements have been performed with EBITs using techniques impossible with conventional ion sources or storage rings. In this paper, I will highlight the various experimental techniques we have developed and the results we have obtained using the EBIT and higher-energy Super-EBIT built at the Lawrence Livermore National Laboratory. The EBIT employs a high-current-density electron beam to trap, ionize, and excite a population of ions. The ions can be studied in situ or extracted from the trap for external experiments. The trapped ions form an ionization-state equilibrium determined by the relative ionization and recombination rates. Ions of several different elements may simultaneously be present in the trap. The ions are nearly at rest, and, for most systems, all in their ground-state configurations. The electron-ion interaction energy has a narrow distribution and can be varied over a wide range. We have used the EBIT devices for the measurement of electron-ion interactions, ion structure, ion-surface interactions, and the behavior of low-density plasmas.
Date: November 2, 1994
Creator: Knapp, D.
Partner: UNT Libraries Government Documents Department

Current issues in perturbative QCD

Description: This review talk discusses some issues of active research in perturbative QCD. The following topics are discussed: (1) current value of {alpha}s; (2) heavy quark production in hadron collisions; (3) production of {Psi} and {Upsilon} in p{anti p} collisions; (4) prompt photon production; (5) small-x and related phenomena; and (6) particle multiplicity in heavy quark jets.
Date: December 1, 1994
Creator: Hinchliffe, I.
Partner: UNT Libraries Government Documents Department

Nonperturbative QCD and elastic processes at CEBAF energies

Description: The authors outline how one can approach nonperturbative aspects of the QCD dynamics studying elastic processes at energies accessible at upgraded CEBAF. Their point is that, in the absence of a complete theory of the nonperturbative effects, a possible way out is based on a systematic use of the QCD factorization procedure which separates theoretically understood (''known'') short-distance effects and nonperturbative (''unknown'') long-distance ones. The latter include hadronic distribution amplitudes, soft components of hadronic form factors etc. Incorporating the QCD sum rule version of the QCD factorization approach, one can relate these nonperturbative functions to more fundamental objects, vacuum condensates, which accumulate information about the nonperturbative structure of the QCD vacuum. The emerging QCD sum rule picture of hadronic form factors is characterized by a dominant role of essentially nonperturbative effects in the few GeV region, with perturbative mechanisms starting to show up for momentum transfer, closer to 10 GeV{sup 2} and higher. Thus, increasing CEBAF energy provides a unique opportunity for a precision study of interplay between the perturbative and nonperturbative phenomena in the QCD description of elastic processes.
Date: October 1, 1994
Creator: Radyushkin, A.
Partner: UNT Libraries Government Documents Department

Heavy quark effective theory

Description: After a brief introduction, the results of application of the heavy quark effective theory to semileptonic decays of beta mesons are discussed. A nearly-model-independent extraction of {vert_bar}V{sub cb}{vert_bar} from data is described. Application of the effective theory to inclusive semileptonic decays of heavy mesons, in semileptonic decays of heavy baryons, and to the nonleptonic decays of hadrons are outlined. The authors conclude by mentioning other areas of research in this very active field.
Date: June 1, 1994
Creator: Roberts, W.
Partner: UNT Libraries Government Documents Department

Reduce phase space quantization of Ashtekar's gravity on de Sitter background

Description: The authors solve perturbative constraints and eliminate gauge freedom for Ashtekar's gravity on de Sitter background. They show that the reduced phase space consists of transverse, traceless, symmetric, fluctuations of the triad and of transverse, traceless, symmetric fluctuations of the connection. A part of gauge freedom corresponding to the conformal Killing vectors of the three-manifold can be fixed only by imposing conditions on Lagrange multiplier. The reduced phase space is equivalent to that of ADM gravity on the same background.
Date: May 1, 1994
Creator: Grigentch, I. & Vassilevich, D.V.
Partner: UNT Libraries Government Documents Department

The proton magnetic form factor in a vector meson dominance model

Description: New precision data for the magnetic form factor of the proton in the time-like region is found to be well represented by a {open_quotes}dipole{close_quotes} vector meson dominance model for both space- like and time-like momentum transfers (for {vert_bar}q{sub 2}{vert_bar} up to {approx} 15 GeV{sup 2}), if the first excited {rho}-meson is taken into account. The authors' result gives a counter example to the previous claim that the new data is only well described by perturbative QCD.
Date: May 1, 1994
Creator: Williams, R. & Krewald, S.
Partner: UNT Libraries Government Documents Department

Bounds on {Delta}B = 1 couplings in the supersymmetric standard model

Description: The most general supersymmetric model contains baryon number violating terms of the form {lambda}{sub ijk} {bar D}{sub i}{bar D}{sub j}{bar U}{sub k} in the superpotential. The authors reconsider the bounds on these couplings, assuming that lepton number conservation ensures proton stability. These operators can mediate n-{anti n} oscillations and double nucleon decay. They show that neutron oscillations do not, as previously claimed, constrain the {lambda}{sub dsu} coupling; they do provide a bound on the {lambda}{sub dbu} coupling, which they calculate. They find that the best bound on {lambda}{sub dsu} arises from double nucleon decay into two kaons; the calculation is discussed in detail. There are no published limits on this process; experimenters are urged to examine this nuclear decay mode. Finally, the other couplings can be bounded by the requirement of perturbative unification.
Date: December 1, 1994
Creator: Goity, J.L. & Sher, Marc
Partner: UNT Libraries Government Documents Department

Leptonic production of baryon resonances

Description: In these lectures, the author focuses on the electromagnetic transition between non-strange baryon states. This sector received much attention in the early 1970's after the development of the first dynamical quark models. However, experimental progress was slow, partly because of the low rates associated with electromagnetic interactions, and partly because of the lack of guidance by theoretical models that went beyond the simplest quark models. It was also difficult for experiments to achieve the precision needed for a detailed analysis of the entire resonance region in terms of the fundamental photocoupling amplitudes over a large range in momentum transfer.
Date: March 1, 1994
Creator: Burkert, V.
Partner: UNT Libraries Government Documents Department

{pi}-A1 electromagnetic form factors and light-cone QCD sum rules

Description: Electromagnetic form factors of the transition {pi} + {gamma}{sub virt.} {r_arrow} A{sub 1} are calculated by QCD sum rules technique with the description of the pion in terms of the set of wave functions of increasing twist. Obtained results are compared with standard QCD sum rule calculations.
Date: October 1, 1994
Creator: Belyaev, V.
Partner: UNT Libraries Government Documents Department

A spinor technique in symbolic Feynman diagram calculation mesons

Description: The authors present a recursive diagrammatic method for evaluating tree-level Feynman diagrams involving multi-fermions which interact through gauge bosons (gluons or photons). Based on this method, a package called COMPUTE, which can generate and calculate all the possible Feynman diagrams for exclusive processes in perturbative QCD, has been developed (available in both Mathematics and Maple). As an example, a calculation of the nucleon Compton scattering amplitude is given.
Date: February 17, 1994
Creator: Pang, A. & Ji, C.
Partner: UNT Libraries Government Documents Department

Goldstone pion and other mesons

Description: A covariant wave equation for q{anti q} interactions with an interaction kernel composed of the sum of constant vector and linear scalar confining interactions is solved for states with two quarks with identical mass. The model includes an NJL-like mechanism which links the dynamical breaking of chiral symmetry to the spontaneous generation of quark mass and the appearance of a low mass Goldstone pion. A novel feature of this approach is that it automatically explains the small mass of the pion even though the linear potential is a scalar interaction in Dirac space, and hence breaks chiral symmetry. Solutions for mesons composed of light quarks ({pi},{rho}, and low lying excited states) and heavy quarks ({rho}{sub c}, J/{Psi}, and low lying excited states) are presented and discussed.
Date: January 1, 1994
Creator: Gross, F. & Milana, J.
Partner: UNT Libraries Government Documents Department

Polarized structure functions of proton and neutron and the Gerasimov-Drell-Hearn and Bjorken sum rules

Description: The value of power corrections to the integrals of the polarization structure functions of proton and neutron {integral} g1{sub p,n}(x)dx measured by the EMC, SMC, and E142 groups, is determined based on a model which accounts for higher twist terms, has the correct asymptotic behavior at large Q{sup 2} and satisfies the Gerasimov-Drell-Hearn sum rule at Q{sup 2}=0. The contribution of resonances up to W=1.8GeV at Q{sup 2}=0 is taken into account based on the analysis of electroproduction data. It is shown that when taking into account these higher twit terms, the experimental data agree with the Bjorken sum rule and part of the proton spin projection carried by quarks, is consistent with the natural estimate of {approximately}50%.
Date: February 1, 1994
Creator: Burkert, V.D. & Ioffe, B.L.
Partner: UNT Libraries Government Documents Department

Heavy mesons in a relativistic model

Description: Motivated by the present interest in the heavy quark effective theory, the authors use the spectator equations to treat the mesonic bound states of heavy quarks. The kernel they use is based on scalar confining and vector Coulomb potentials. Wave functions are treated to leading order and energies to order 1/m{sub Q} in the heavy-light systems, and order 1/m{sub Q{sup 2}} in heavy-heavy systems. Their results are in reasonable agreement with experimental measurements. They estimate two of the parameters of the heavy quark effective theory, and propose further calculations that may be undertaken in the future.
Date: December 1, 1994
Creator: Zeng, J.; Orden, J. & Roberts, W.
Partner: UNT Libraries Government Documents Department

Massless fermions on the lattice

Description: The authors consider a nonlocal lattice action for fermions fermion doubling in lattice theories. It is shown, that it is possible to avoid the fermionic doubling in the case of free fermions, but this approach does not reproduce results for the effective action for gauge fields in the continuum theory, because the high frequency fermion modes have a strong dependence on the gauge field.
Date: December 1, 1994
Creator: Belyaev, V.M.
Partner: UNT Libraries Government Documents Department