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400-MeV upgrade for the Fermilab linac (open access)

400-MeV upgrade for the Fermilab linac

Fermilab plans to upgrade the Tevatron to expand the physics research program in both the fixed target and the collider operating modes. The first phase of this program is to increase the energy of the H{sup -} linac from 200 to 400 MeV in order to reduce the incoherent space change tuneshift at injection into the Booster which can limit either the brightness or the total intensity of the beam. The linac upgrade will be achieved by replacing the last four 201 MeV, with seven 805 MHz side-coupled cavity modules operating at an average axial field of about 8 MV/m. This will allow acceleration to 400 MeV in the existing Linac enclosure. 4 refs., 3 figs., 1 tab.
Date: September 1, 1989
Creator: Young, D.E. & Noble, R.J.
System: The UNT Digital Library
An 805 MHz disk and washer accelerating structure with coaxial coupler for the Fermilab upgrade (open access)

An 805 MHz disk and washer accelerating structure with coaxial coupler for the Fermilab upgrade

The Disk and Washer (DAW) structure with four bi-periodic tees to support the washers has been studied at Fermilab for the Linac Upgrade by constructing two, 805 MHz, one-meter sections joined by a coaxial coupler. The coupler provides an rf drive port, an adjustable tuner, a vacuum port, and an enclosure for the installation of beam focussing and monitoring devices. This configuration is suitable for a high beta proton linear accelerator. The bi-periodic tee supports in the DAW structure suppress the TM{sub 11} mode at the operating frequency which has been a problem with previous designs. Frequency-mode spectra have been calculated and measured as well as the quantities Q, R/Q, and ZT{sup 2}. The structure has been evacuated and operated at high power levels and high accelerating fields. 5 refs., 4 figs., 2 tabs.
Date: September 1, 1989
Creator: Young, D. E.; Moretti, A.; Lee, G.; Mills, F. E.; Zhou, P. (Fermi National Accelerator Lab., Batavia, IL (USA)); Swenson, D. A. et al.
System: The UNT Digital Library
Abstracts submitted for the thirty-first annual meeting, Division of Plasma Physics, November 13--17, 1989 (open access)

Abstracts submitted for the thirty-first annual meeting, Division of Plasma Physics, November 13--17, 1989

This report contains abstracts of papers that are submitted for the 31st annual meeting of the Division of Plasma Physics, November 13--17, 1989. (LSP)
Date: September 1, 1989
Creator: unknown
System: The UNT Digital Library
Alpha particle emitters in medicine (open access)

Alpha particle emitters in medicine

Radiation-induced cancer of bone, liver and lung has been a prominent harmful side-effect of medical applications of alpha emitters. In recent years, however, the potential use of antibodies labeled with alpha emitting radionuclides against cancer has seemed promising because alpha particles are highly effective in cell killing. High dose rates at high LET, effectiveness under hypoxic conditions, and minimal expectancy of repair are additional advantages of alpha emitters over antibodies labeled with beta emitting radionuclides for cancer therapy. Cyclotron-produced astatine-211 ({sup 211}At) and natural bismuth-212 ({sup 212}Bi) have been proposed and are under extensive study in the United States and Europe. Radium-223 ({sup 223}Ra) also has favorable properties as a potential alpha emitting label, including a short-lived daughter chain with four alpha emissions. The radiation dosimetry of internal alpha emitters is complex due to nonuniformly distributed sources, short particle tracks, and high relative specific ionization. The variations in dose at the cellular level may be extreme. Alpha-particle radiation dosimetry, therefore, must involve analysis of statistical energy deposition probabilities for cellular level targets. It must also account fully for nonuniform distributions of sources in tissues, source-target geometries, and particle-track physics. 18 refs., 4 figs.
Date: September 1, 1989
Creator: Fisher, D. R.
System: The UNT Digital Library
The ALS (Advanced Light Source): A third generation light source (open access)

The ALS (Advanced Light Source): A third generation light source

The Advanced Light Source, a third-generation national synchrotron-radiation facility now under construction at the Lawrence Berkeley Laboratory, is scheduled to begin serving qualified users across a broad spectrum of research areas in April 1993. Based on a low- emittance electron storage ring optimized to operate at 1.5 GeV, the ALS will have 11 long straight sections available for insertion devices (undulators and wigglers). Undulators will generate high- brightness soft x-ray and ultraviolet (XUV) radiation; wigglers will extend the spectrum generated into the hard x-ray region, but at a lower brightness. Up to 48 bending-magnet ports will also be available. Engineering design has begun on a complement of three undulators with periods of 8.0, 5.0, and 3.9 cm that between them will cover the photon-energy range from 5.4 eV to 2.5 keV when the first, third, and fifth harmonics are used, as well as a wiggler with a critical energy of 3.1 keV. Undulator beam lines will be based on high-resolution spherical-grating monochromators. A Call for Proposals has been issued for those who wish to participate in the design, development, commissioning, and operation of the initial complement of ALS experimental facilities (insertion devices, beam lines, and experimental stations) as members of …
Date: September 1, 1989
Creator: Robinson, A. L. & Schlachter, A. S.
System: The UNT Digital Library
Analysis of quench-vent pressures for present design of ITER (International Thermonuclear Experimental Reactor) TF (toroidal field) coils (open access)

Analysis of quench-vent pressures for present design of ITER (International Thermonuclear Experimental Reactor) TF (toroidal field) coils

The International Thermonuclear Experimental Reactor (ITER) is a new tokamak design project with joint participation from Japan, the European Community, the Union of the Soviet Union, and the United States. This paper examines the effects of a quench within the toroidal field (TF) coils based on current ITER design. It is a preliminary, rough analysis. Its intent is to assist ITER designers while more accurate computer codes are being developed and to provide a check against these more rigorous solutions. Rigorous solutions to the quench problem are very complex involving three- dimensional heat transfer, extreme changes in heat capacities and copper resistivity, and varying flow dynamics within the conductors. This analysis addresses all these factors in an approximate way. The result is much less accurate than a rigorous analysis. Results here could be in error as much as 30 to 40 percent. However, it is believed that this paper can still be very useful to the coil designer. Coil pressures and temperatures vs time into a quench are presented. Rate of helium vent, energy deposition in the coil, and depletion of magnetic stored energy are also presented. Peak pressures are high (about 43 MPa). This is due to the very …
Date: September 20, 1989
Creator: Slack, D.S.
System: The UNT Digital Library
Analytical methods for predicting contaminant transport (open access)

Analytical methods for predicting contaminant transport

This paper summarizes some of the previous and recent work at the University of California on analytical solutions for predicting contaminate transport in porous and fractured geologic media. Emphasis is given here to the theories for predicting near-field transport, needed to derive the time-dependent source term for predicting far-field transport and overall repository performance. New theories summarized include solubility-limited release rate with flow backfill in rock, near-field transport of radioactive decay chains, interactive transport of colloid and solute, transport of carbon-14 as carbon dioxide in unsaturated rock, and flow of gases out of and a waste container through cracks and penetrations. 28 refs., 4 figs.
Date: September 1, 1989
Creator: Pigford, T.H.
System: The UNT Digital Library
Anisotropy of oxygen tracer diffusion in YBa sub 2 Cu sub 3 O sub 7-. delta. single crystals (open access)

Anisotropy of oxygen tracer diffusion in YBa sub 2 Cu sub 3 O sub 7-. delta. single crystals

The crystal structure of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} strongly suggests that the diffusion of oxygen in this material will be highly anisotropic, with diffusion in the ab plane being much faster than diffusion parallel to the c axis, and this has been assumed in most analyses of diffusion in YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}. The present data confirm this hypothesis; the diffusion coefficient in the ab plane is several orders of magnitude greater than the diffusion coefficient along the c axis. Some interesting artifacts of the measurement, due to this strong anisotropy, are also revealed. Oxygen exchange in polycrystalline samples of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} is discussed in terms of these results. 15 refs., 9 figs.
Date: September 1, 1989
Creator: Rothman, S. J.; Routbort, J. L.; Liu, J.-Z.; Downey, J. W.; Thompson, L. J.; Fang, Y. et al.
System: The UNT Digital Library
B production in hadron collisions: Theory (open access)

B production in hadron collisions: Theory

A review is presented of heavy quark production in {bar p}p, {pi}{sup -}p, and pp interactions at fixed target and collider energies. Calculations of total cross sections and of single quark inclusive differential cross sections d{sup 2}{sigma}/dk{sub T}dy are described including contributions through next-to-leading order in QCD perturbation theory. Comparisons with available data on charm and bottom quark production show good agreement for reasonable values of the charm and bottom quark masses and other parameters. Predictions and open issues in the interpretation of results are summarized. 20 refs., 5 figs.
Date: September 28, 1989
Creator: Berger, E. L.
System: The UNT Digital Library
Beam dynamics in linear colliders (open access)

Beam dynamics in linear colliders

In this paper, we discuss some basic beam dynamics issues related to obtaining and preserving the luminosity of a next generation linear collider. 17 refs., 1 fig.
Date: September 1, 1989
Creator: Ruth, R. D.
System: The UNT Digital Library
Biomodal spontaneous fission (open access)

Biomodal spontaneous fission

Investigations of mass and kinetic-energy distributions from spontaneous fission have been extended in recent years to an isotope of element 104 and, for half-lives, to an isotope of element 108. The results have been surprising in that spontaneous fission half-lives have turned out to be much longer than expected and mass and kinetic- energy distributions were found to abruptly shift away from those of the lighter actinides, showing two modes of fission. These new developments have caused a re-evaluation of our understanding of the fission process, bringing an even deeper appreciation of the role played by nuclear shell effects upon spontaneous fission properties. 16 refs., 10 figs.
Date: September 26, 1989
Creator: Hulet, E.K. (Lawrence Livermore National Lab., CA (USA))
System: The UNT Digital Library
A blanket design, apparatus, and fabrication techniques for the mass production of multilayer insulation blankets for the Superconducting Super Collider (open access)

A blanket design, apparatus, and fabrication techniques for the mass production of multilayer insulation blankets for the Superconducting Super Collider

The multilayer insulation (MLI) system for the Superconducting Super Collider (SSC) consists of full cryostat length assemblies of aluminized polyester film fabricated in the form of blankets and installed as blankets to the 4.5K cold mass and the 20K and 80K thermal radiation shields. Approximately 40,000 MLI blankets will be required in the 10,000 cryogenic devices comprising the SSC accelerator. Each blanket is nearly 17 meters long and 1.8 meters wide. This paper reports the blanket design, an apparatus, and the fabrication method used to mass produce pre-fabricated MLI blankets. Incorporated in the blanket design are techniques which automate quality control during installation of the MLI blankets in the SSC cryostat. The apparatus and blanket fabrication method insure consistency in the mass produced blankets by providing positive control of the dimensional parameters which contribute to the thermal performance of the MLI blanket. By virtue of the fabrication process, the MLI blankets have inherent features of dimensional stability three-dimensional uniformity, controlled layer density, layer-to-layer registration, interlayer cleanliness, and interlayer material to accommodate thermal contraction differences. 11 refs., 6 figs., 1 tab.
Date: September 1, 1989
Creator: Gonczy, J. D.; Boroski, W. N.; Niemann, R. C.; Otavka, J. G.; Ruschman, M. K. & Schoo, C. J.
System: The UNT Digital Library
Coherent pair creation from beam-beam interaction (open access)

Coherent pair creation from beam-beam interaction

It has recently been recognized that in future linear colliders, there is a finite probability that the beamstrahlung photons will turn into e{sup +}e{sup {minus}} pairs induced by the same beam-beam field, and this would potentially cause background problems. In this paper, we first review the probability of such a coherent pair creation process. It is seen that the constraint on the beamstrahlung parameter, {Upsilon}, is tight of these coherent pairs to be totally suppressed. We then point out that there exists a minimum energy for the pair-created particles, which scales as {approximately}1/5{Upsilon}. When combining this condition with the deflection angle for the low-energy particles, the constraint on the allowable {Upsilon} value is much relaxed. Finally, we calculate the effective cross section for producing the weak bosons by the low-energy e{sup +}e{sup {minus}} pairs. It is shown that these cross sections are substantial for {Upsilon} > 1. We suggest that this effect can help to autoscan the particle spectrum in the high energy frontier. 10 refs., 2 figs.
Date: September 1, 1989
Creator: Chen, Pisin.
System: The UNT Digital Library
A comparison of hydrogen vs. helium glow discharge effects on fusion device first-wall conditioning (open access)

A comparison of hydrogen vs. helium glow discharge effects on fusion device first-wall conditioning

Hydrogen- and deuterium-fueled glow discharges are used for the initial conditioning of magnetic fusion device vacuum vessels following evacuation from atmospheric pressure. Hydrogenic glow discharge conditioning (GDC) significantly reduces the near-surface concentration of simple adsorbates, such as H/sub 2/O, CO, and CH/sub 4/, and lowers ion-induced desorption coefficients by typically three orders of magnitude. The time evolution of the residual gas production observed during hydrogen-glow discharge conditioning of the carbon first-wall structure of the TFTR device is similar to the time evolution observed during hydrogen GDC of the initial first-wall configuration in TFTR, which was primarily stainless steel. Recently, helium GDC has been investigated for several wall-conditioning tasks on a number of tokamaks including TFTR. Helium GDC shows negligible impurity removal with stainless steel walls. For impurity conditioning with carbon walls, helium GDC shows significant desorption of H/sub 2/O, CO, and CO/sub 2/; however, the total desorption yield is limited to the monolayer range. In addition, helium GDC can be used to displace hydrogen isotopes from the near-surface region of carbon first-walls in order to lower hydrogenic retention and recycling. 38 refs., 6 figs.
Date: September 1, 1989
Creator: Dylla, H.F.
System: The UNT Digital Library
Confinement and the Pomeron (open access)

Confinement and the Pomeron

The importance of confinement for obtaining a unitary high-energy limit for QCD is discussed. Minijets'' are argued to build up non-unitary behavior{endash}when k{sub T} {gt} {Lambda} is imposed. For minijets to mix with low k{sub T} Pomeron Field Theory describing confinement, and give consistent asymptotic behavior, new quarks'' must enter the theory above the minijet transverse momentum scale. The Critical Pomeron is the resulting high-energy limit. 22 refs.
Date: September 25, 1989
Creator: White, A.R.
System: The UNT Digital Library
Correlation of waterside corrosion and cladding microstructure in high-burnup fuel and gadolinia rods (open access)

Correlation of waterside corrosion and cladding microstructure in high-burnup fuel and gadolinia rods

Waterside corrosion of the Zircaloy cladding has been examined in high-burnup fuel rods from several BWRs and PWRs, as well as in 3 wt % gadolinia burnable poison rods obtained from a BWR. The corrosion behavior of the high-burnup rods was then correlated with results from a microstructural characterization of the cladding by optical, scanning-electron, and transmission-electron microscopy (OM, SEM, and TEM). OM and SEM examination of the BWR fuel cladding showed both uniform and nodular oxide layers 2 to 45 {mu}m in thickness after burnups of 11 to 30 MWd/kgU. For one of the BWRs, which was operated at 307{degree}C rather than the normal 288{degree}C, a relatively thick (50 to 70 {mu}m) uniform oxide, rather than nodular oxides, was observed after a burnup of 27 to 30 MWd/kgU. TEM characterization revealed a number of microstructural features that occurred in association with the intermetallic precipitates in the cladding metal, apparently as a result of irradiation-induced or -enhanced processes. The BWR rods that exhibited white nodular oxides contained large precipitates (300 to 700 nm in size) that were partially amorphized during service, indicating that a distribution of the large intermetallic precipitates is conductive to nodular oxidation. 23 refs., 9 figs.
Date: September 1, 1989
Creator: Chung, H.M. (Argonne National Lab., IL (USA))
System: The UNT Digital Library
Cosmic Strings and Baryon Decay Catalysis (open access)

Cosmic Strings and Baryon Decay Catalysis

Cosmic strings, like monopoles, can catalyze proton decay. For integer charged fermions, the cross section for catalysis is not amplified, unlike in the case of monopoles. We review the catalysis processes both in the free quark and skyrmion pictures and discuss the implications for baryogenesis. We present a computation of the cross section for monopole catalyzed skyrmion decay using classical physics. We also discuss some effects which can screen catalysis processes. 32 refs., 1 fig.
Date: September 1, 1989
Creator: Gregory, R.; Perkins, W. B.; Davis, A. C. & Brandenberger, R. H.
System: The UNT Digital Library
Current status of E/f sub 1 (1420) and. iota. /. eta. (1450) (open access)

Current status of E/f sub 1 (1420) and. iota. /. eta. (1450)

The current status and future prospects are given of the E/f{sub 1} (1420) and the {eta}(1430) region containing the {iota}/{eta}(1450). These states are seen in the channels K{bar K}{pi} and {eta}{pi}{pi}. 43 refs., 10 figs., 5 tabs.
Date: September 1, 1989
Creator: Chung, S.U. (Brookhaven National Lab., Upton, NY (USA))
System: The UNT Digital Library
Deformed ODD-ODD nuclei: Matrix elements for the residual n-p interaction and patterns of alternating perturbations in level spacings (open access)

Deformed ODD-ODD nuclei: Matrix elements for the residual n-p interaction and patterns of alternating perturbations in level spacings

The application of a simple semi-empirical model is discussed in terms of interpreting experimental nuclear structure data for twelve of the best characterized odd-odd deformed nuclei. An essential part of this modeling is to calculate values for the Gallagher-Moszkowski splittings and Newby shifts, the observables that arise from the n-p residual interaction in odd-odd nuclei. Assumptions regarding the form for this n-p force are traced historically. The predictive power of a favored form of the n-p force, one that includes a central force with short and long-range components, a tensor force, and some effects of core polarization, is examined in light of experimental data obtained since its formulation. A data set of 42 experimentally determined Newby shifts has been reviewed as to the reliability of each entry. Exceptions to a recently proposed rule for the a priori determination of the sign of Newby shift are discussed. Evidence is presented for the existence of an odd-even staggering or signature effect in the rotational spacings of many K{sup {minus}} bands (with K > 0). By use of Coriolis-coupling calculations, it has been possible to reproduce the staggering observed in some of the K{sup {minus}} rotational bands of {sup 156}Tb, {sup 168}Tm, {sup …
Date: September 1, 1989
Creator: Hoff, R.W.; Jain, A.K.; Kvasil, J.; Sood, P.C.; Sheline, R.K. (Lawrence Livermore National Lab., CA (USA) & Florida State Univ., Tallahassee, FL (USA))
System: The UNT Digital Library
Deformed Proximity Potential for Heavy Ion Reactions (open access)

Deformed Proximity Potential for Heavy Ion Reactions

The proximity potential is discussed for the inelastic scattering of a spherical nucleus on a deformed nucleus or the mutual interaction of two deformed nuclei. It is shown that the proximity potential is, in general, geometrically more correct than the usual centerline prescription used in inelastic scattering analyses. For the cases where the proximity potential is inadequate a folding model approach is advocated. Techniques to facilitate the coupled channels analysis are presented. 11 refs., 6 figs.
Date: September 1, 1989
Creator: Baltz, A. J.
System: The UNT Digital Library
Design considerations in achieving 1 MW CW operation with a whispering-gallery-mode gyrotron (open access)

Design considerations in achieving 1 MW CW operation with a whispering-gallery-mode gyrotron

Varian is developing high-power, CW gyrotrons at frequencies in the range 100 GHz to 150 GHz, for use in electron cyclotron heating applications. Early test vehicles have utilized a TE{sub 15,2,1} interaction cavity, have achieved short-pulse power levels of 820 kW and average power levels of 80 kW at 140 GHz. Present tests are aimed at reaching 400 kW under CW operating conditions and up to 1 MW for short pulse durations. Work is also underway on modifications to the present design that will enable power levels of up to 1 MW CW to be achieved. 7 refs., 2 figs.
Date: September 1, 1989
Creator: Felch, K.; Feinstein, J.; Hess, C.; Huey, H.; Jongewaard, E.; Jory, H. et al.
System: The UNT Digital Library
ECR sources for the production of highly charged ions (open access)

ECR sources for the production of highly charged ions

Electron Cyclotron Resonance Ion Sources (ECRIS) using RF between 5 and 16 GHz have been developed into stable, reliable sources of highly charged ions produced from a wide range of elements. These devices are currently used as ion sources for cyclotrons, synchrotrons, and heavy-ion linacs for nuclear and relativistic heavy-ion physics. They also serve the atomic physics community as a source of low energy multiply-charged ions. In order to improve their performance both with respect to maximum charge state and beam intensity, ECRIS builders are now designing and constructing sources which will operate at frequencies up to 30 GHz. In this paper we review the present status of operating ECRIS, review recent experimental measurements on plasma parameters, and look at the technology and potential of sources operating at frequencies up to 30 GHz. 14 refs., 4 figs., 1 tab.
Date: September 1, 1989
Creator: Lyneis, C.M.; Antaya, T.A (Lawrence Berkeley Lab., CA (USA) & Michigan State Univ., East Lansing, MI (USA))
System: The UNT Digital Library
Effects of irradiation on intergranular stress corrosion cracking of Type 304 stainless steel (open access)

Effects of irradiation on intergranular stress corrosion cracking of Type 304 stainless steel

Constant extension rate tests (CERT) were run on ten irradiated specimens in continuation of a study of environmental effects on intergranular stress corrosion cracking of type 304 stainless steel. Specimens of both furnace sensitized and annealed material were irradiated to fluences of 1 to 2 {times} 10{sup 21} neutrons (E {ge} 0.1 Mev) per square centimeter at a temperature of {approximately}150{degree}C in a reflector position of the High Flux Isoptope Reactor at ORNL. CERT test conditions duplicated conditions for testing of non-irradiated specimens. The time-to-failure for the sensitized and irradiated specimens showed the same pattern of dependence on test variables as the non-irradiated specimens in an associated study. The annealed and irradiated specimens showed no evidence of irradiation assisted stress corrosion cracking.
Date: September 15, 1989
Creator: Caskey, G. R.; Ondrejcin, R. S.; Aldred, P.; Davis, R. B. & Wilson, S. A.
System: The UNT Digital Library
Effects of irradiation on intergranular stress corrosion cracking of Type 304 stainless steel (open access)

Effects of irradiation on intergranular stress corrosion cracking of Type 304 stainless steel

Constant extension rate tests (CERT) were run on ten irradiated specimens in continuation of a study of environmental effects on intergranular stress corrosion cracking of type 304 stainless steel. Specimens of both furnace sensitized and annealed material were irradiated to fluences of 1 to 2 {times} 10{sup 21} neutrons (E {ge} 0.1 Mev) per square centimeter at a temperature of {approximately}150{degree}C in a reflector position of the High Flux Isoptope Reactor at ORNL. CERT test conditions duplicated conditions for testing of non-irradiated specimens. The time-to-failure for the sensitized and irradiated specimens showed the same pattern of dependence on test variables as the non-irradiated specimens in an associated study. The annealed and irradiated specimens showed no evidence of irradiation assisted stress corrosion cracking.
Date: September 15, 1989
Creator: Caskey, G. R.; Ondrejcin, R. S. (Westinghouse Savannah River Co., Aiken, SC (United States)); Aldred, P.; Davis, R. B. & Wilson, S. A. (General Electric Co., San Jose, CA (United States))
System: The UNT Digital Library