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Nuclear breakup and particle densities in 200 A GeV - /sup 16/O interactions with emulsion nuclei

Description: Experiment EMU-01 makes use of emulsion chambers and conventional stacks to study the interactions in matter of 200 A GeV /sup 16/O nuclei accelerated at the CERN SPS. Projectile fragmentation is compatible with such interactions of /sup 16/O nuclei at 2 A GeV, indications of limiting fragmentation. Particle production is examined via high precision pseudo-rapidity distributions. Energy densities up to about 3 GeVfm/sup 3/ are observed in central /sup 16/O + Ag(Br) interactions. Pseudo-rapidity… more
Date: September 1, 1987
Creator: Adamovich, M.I.; Alexandrov, Y.A.; Asimov, S.A.; Badyal, S.K.; Basova, E. & Bhalla, K.B.
Partner: UNT Libraries Government Documents Department
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Advances in inherently conducting polymers

Description: The discovery of polyacetylene as the prototype material led to extensive research on its synythesis and characterization. The techniques that emerged as the most important and promising ones are those that dealt with molecular orientation and that resulted in conductivities almost as high as that of copper. The study of dozens of other materials followed. Interest in conducting polymers stems from their nonclassical optical and electronic properties as well as their potential technological app… more
Date: September 1, 1987
Creator: Aldissi, M.
Partner: UNT Libraries Government Documents Department
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Conducting hybrid polymeric systems

Description: The studies took advantage of the opportunities offered by copolymerization for gaining insight into electrical conduction, morphology, phase separation, polymer-polymer interfaces, and solubility. Copolymerization is technologically important for it allows one to tailor-make products with specifically desired properties. However, the utility of copolymerization involving conjugated, rigid components could be different from that of conventional polymers. This paper is focused on the synthesis a… more
Date: September 1, 1987
Creator: Aldissi, M.; White, J.W.; Agnew, S. & Jorgensen, B.S.
Partner: UNT Libraries Government Documents Department
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The Direct Application of Geothermal Energy to Provide Process Heat in Guatemala

Description: One part of an energy and resource development program in Central America is a geothermal process heat project in Guatemala. The feasibility of the direct heat application depends upon the production characteristics and reliability of the geothermal source. Other factors are the distance from the heat source, quantity of use, and capacity factor of the use facilities. Favorable conditions would be distances of under 5 km, heat requirements approximately equal to the well capacity, and high capa… more
Date: September 1, 1987
Creator: Altseimer, John H. & Edeskuty, Frederick J.
Partner: UNT Libraries Government Documents Department
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A Search for Flavour Changing Neutral Current Processes in Decays of Charmed Mesons

Description: Neutral current interactions are known from studies of K meson decays to conserve flavor to a high precision. Although flavor changing neutral currents (FCNC) are forbidden in the Weinberg-Salam model, many extensions of the Standard Model allow such processes. We present preliminary upper limits on FCNC-mediated decays of charmed particles, namely D/sup 0/ ..-->.. e/sup +/e/sup -/, D/sup 0/ ..-->.. ..mu../sup +/..mu../sup -/, D/sup 0/ ..-->.. ..mu..e and D/sup +/ ..-->.. ..pi../sup +/..mu..e.
Date: September 1, 1987
Creator: Anjos, J. C.; Appel, J. A.; Bracker, S. B.; Browder, T. E.; Cremaldi, L. M.; Elliott, J. R. et al.
Partner: UNT Libraries Government Documents Department
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A Study of the Semileptonic Decay Mode D/Sup 0/. -->. K/Sup -/E/Sup +/Nu/Sub E/

Description: We present an analysis of the exclusive semileptonic decay mode D/sup 0/ ..-->.. K/sup -/e/sup +/nu/sub e/. We have measured the ratio of decay rates GAMMA(D/sup 0/ ..-->.. K/sup -/e/sup +/nu/sub e/)/GAMMA(D/sup 0/ ..-->.. K/sup -/..pi../sup +/). After correcting for the reconstruction efficiencies and subtracting the contribution from other decay modes we have found the ratio to be equal to 0.77 +- 0.12(stat) +- 0.13(syst).
Date: September 1, 1987
Creator: Anjos, J. C.; Appel, J. A.; Bracker, S. B.; Browder, T. E.; Cremaldi, L. M.; Elliott, J. R. et al.
Partner: UNT Libraries Government Documents Department
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Limits on the transverse phase space density in the Fermilab Booster

Description: Recent results on intensity and transverse density limitations in the Fermilab 8-GeV Booster are presented. The evidence suggests that the limits are set by incoherent space-charge effects at low energy. Data are interpreted in terms of the space-charge tune shift and possible means of improving performance further are discussed. 8 refs., 3 figs.
Date: September 1, 1987
Creator: Ankenbrandt, C. & Holmes, S.D.
Partner: UNT Libraries Government Documents Department
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Positron-annihilation 2D-ACAR studies of disordered and defected alloys

Description: Theoretical and experimental progess in connection with 2D-ACAR positron annihilation studies of ordered, disordered, and defected alloys is discussed. We present, in particular, some of the recent developments concerning the electronic structure of disordered alloys, and the work in the area of annihilation from positrons trapped at vacancy-type defects in metals and alloys. The electronic structure and properties of a number of compounds are also discussed briefly; we comment specifically on … more
Date: September 1, 1987
Creator: Bansil, A.; Prasad, R.; Smedskjaer, L. C.; Benedek, R. & Mijnarends, P. E.
Partner: UNT Libraries Government Documents Department
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The stability of free-electron lasers against filamentation

Description: In inertial confinement fusion (ICF) experiments, the high electromagnetic fields propagating through a relatively dense plasma can result in a transverse instability, causing the matter and light to form filaments oriented parallel to the light beam. We examine whether a similar instability exists in the electron beam of a free-electron laser, where such an instability could interfere with the transfer of beam kinetic energy into optical wave energy. We heuristically examine the instability in… more
Date: September 15, 1987
Creator: Barnard, J. J.; Scharlemann, E. T. & Yu, S. S.
Partner: UNT Libraries Government Documents Department
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Initial electron distributions for free-electron lasers generated by injector and accelerator simulations

Description: Early free-electron laser (FEL) development was guided by simple performance criteria based on the number of undulator periods, electron beam quality, and current. The beam quality (emittance and energy spread) was used to characterize the initial distribution of axial electron velocities along the undulator axis. While the emittance and energy spread determine the overall width of the distribution, its detailed shape is also important. As new accelerators are designed specifically for FEL appl… more
Date: September 16, 1987
Creator: Boyd, J. K.; Colson, W. B. & Scharlemann, E. T.
Partner: UNT Libraries Government Documents Department
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The purposes, achievements, and priorities of arms control

Description: Arms control purposes include strengthening the framework of deterrence and reducing the threat of the use of nuclear weapons, reducing the dangers of attack and accidental nuclear war, and allowing more resources for the civilian economy. The paper briefly describes achievements in arms control since World War II. These include the Limited Test Ban Treaty (LTBT), Nonproliferation Treaty (NPT), Anti-Ballistic Missile Treaty (ABMT)-SALT I, SALT II, Threshold Test Ban Treaty (TTBT), Peaceful Nucl… more
Date: September 1, 1987
Creator: Brown, P.S.
Partner: UNT Libraries Government Documents Department
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Quality application to space nuclear power (SP-100)

Description: Westinghouse Hanford Company (WHC) was selected by DOE as the preferred site to install and conduct operational, performance, and reliability tests on the ground-based prototype of the space reactor. These tests will be conducted with the reactor in a large vacuum chamber to simulate the space environment. A containment vessel system from the decommissioned Plutonium Recycle Test Reactor will house the chamber and provide appropriate safeguards. The reactor will generate 2.5-MW thermal energy f… more
Date: September 1, 1987
Creator: Caplinger, W.H.
Partner: UNT Libraries Government Documents Department
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Channeling and dechanneling at high energy

Description: The possibility of using channeling as a tool for high energy particle physics has now been extensively investigated. Bent crystals have been used as an accelerator extraction element and for particle deflection. Applications as accelerating devices have been discussed but appear remote. The major advantage in using a bent crystal rather than a magnet is the large deflection that can be achieved in a short length. The major disadvantage is the low transmission. A good understanding of dechannel… more
Date: September 30, 1987
Creator: Carrigan, R. A., Jr.
Partner: UNT Libraries Government Documents Department
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The use of toroidal boundary conditions in the program POISSON

Description: In circular particle accelerators of moderate size, one cannot entirely neglect the curvature of the structure and of the guide field. In practice, one may wish to restrict the region of analysis to that near the working aperture, while excluding a very substantial area closer to (and including) the axis of rotational symmetry. In this way, a more efficient mesh can be generated for a program such as POISSON. In restricting the solution to the region of interest, there must be concern regarding… more
Date: September 1, 1987
Creator: Caspi, S.; Helm, M. & Laslett, L.J.
Partner: UNT Libraries Government Documents Department
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Wavelengths of the 3p-3d transitions of the Co- and Fe-like ions: The effects of electron correlation

Description: The experimental observations of the 3p/sup 6/ 3d/sup 9/ /sup 2/D - 3p/sup 5/ 3d/sup 10/ /sup 2/p transitions of the Co-like ions and 3p/sup 6/ 3d/sup 8/ /sup 3/F/sub 4/ - 3p/sup 5/ 3d/sup 9/ /sup 3/F/sub 3/ of the Fe-like ions have recently been extended to highly charged ions of heavy elements up to uranium (Z = 92). A comparison between the observed energies and calculated values from the Dirac-Fock model indicated persistent discrepancies of 3 to 4 eV for all ions. Systematic multiconfigura… more
Date: September 2, 1987
Creator: Chen, Mau Hsiung
Partner: UNT Libraries Government Documents Department
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Long-term aging of cast stainless steels: Mechanisms and resulting properties

Description: Mechanical property data are presented from Charpy-impact, tensile, and J-R curve tests for several heats of cast stainless steel aged up to 10,000 h at 450, 400, 350, 320, and 290/sup 0/C. The results indicate that thermal aging increases the tensile strength and decreases the impactenergy, J/sub IC/ and tearing modulus of the steels. Also, the ductile-to-brittle transition curve shifts to higher temperatures. The low-carbon CF-3 steels were the most resistant and the molybdenum-containing hig… more
Date: September 1, 1987
Creator: Chopra, O. K. & Chung, H. M.
Partner: UNT Libraries Government Documents Department
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ECRH (electron-cyclotron resonance heating)-heated distributions in thermal-barrier tandem mirrors

Description: The distribution function is calculated for electrons subjected to strong electron-cyclotron resonance heating (ECRH) at the plug and barrier in a tandem-mirror thermal-barrier cell. When ECRH diffusion locally dominates over collisions and a boundary condition (associated with electrons passing to the center cell) imposes variations on the distribution function rapid compared to the variation of the ECRH and collisional diffusion coefficients, the kinetic equation can be reduced approximately … more
Date: September 1, 1987
Creator: Cohen, R. H. & LoDestro, L. L.
Partner: UNT Libraries Government Documents Department
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Analysis of exposure due to work on activated components

Description: In this brief note the author summarized analysis of the exposure incurred in various maintenance jobs involving activated accelerator and beam line components at Fermilab. A tabulation was made of parameters associated with each job. Included are rather terse descriptions of the various tasks. The author presented various plots of the quantities in the table. All exposure rates are mR/hr while all exposures accumulated are mR. The exposure rates were generally measured at the Fermilab standard… more
Date: September 1, 1987
Creator: Cossairt, J.D.
Partner: UNT Libraries Government Documents Department
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Residual radioactivity measurements along the PB target pile

Description: In this brief note, measurements of residual radioactivity made along the PB target pile will be described. This was done as a test of the methods described by P. Gollon (Go76) for predicting such radioactivity based upon surface star density calculations using CASIM. These methods have been extensively used at Fermilab, especially in the design of the Tevatron II target piles. 4 refs., 2 figs.
Date: September 1, 1987
Creator: Cossairt, J.D.
Partner: UNT Libraries Government Documents Department
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Charm Hadroproduction Results From Fermilab E-400

Description: Results are presented from Fermilab E-400 on the production of charmed baryons and mesons at a mean energy of 640 GeV. We show evidence for the charm-strange baryon, ..xi../sub c//sup +/, and present our measurements of its mass, width, lifetime, cross section and relative branching fractions, and the A, x/sub f/, p/sub t/, and particle/antiparticle dependence of the state. We show evidence for both the ..sigma../sub c//sup 2 +/ and ..sigma../sub c//sup 0/, and present measurements of three mas… more
Date: September 1, 1987
Creator: Coteus, P.; Binkley, M.; Bossi, F.; Butler, J.; Cumalat, J. P.; DiCorato, M. et al.
Partner: UNT Libraries Government Documents Department
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Cermet fuel reactors

Description: Cermet fueled nuclear reactors are attractive candidates for high performance space power systems. The cermet fuel consists of tungsten-urania hexagonal fuel blocks characterized by high strength at elevated temperatures, a high thermal conductivity and resultant high thermal shock resistance. Key features of the cermet fueled reactor design are (1) the ability to achieve very high coolant exit temperatures, and (2) thermal shock resistance during rapid power changes, and (3) two barriers to fi… more
Date: September 1, 1987
Creator: Cowan, C. L.; Palmer, R. S.; Van Hoomissen, J. E.; Bhattacharyya, S. K. & Barner, J. O.
Partner: UNT Libraries Government Documents Department
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Effect of the subgap conductance on the metastable states in a Josephson tunnel junction

Description: An investigation of the decay rate of metastable states in Josephson tunnel junctions in presence of thermal noise is presented. We have observed that, in the extremely underdamped regime, there is an exponential temperature dependence of the best fit value for the shunt conductance. Such a dependence shows a close relation with the temperature dependence of the subgap conductance, suggesting that the effective conductance for the escape from the metastable states obeys to a quasi-particle ther… more
Date: September 1, 1987
Creator: Cristiano, R.; Pagano, S.; Silvestrini, P.; Gray, K.E. & Liengme, O.
Partner: UNT Libraries Government Documents Department
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[Dialog, September 1987: President's Message]

Description: President's message from the September 1987 edition of Diaog. Some sentences are highlighted.
Date: September 1987
Creator: Dallas Gay Alliance
Partner: UNT Libraries Special Collections
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