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Making sense of anomalous gauge theories (open access)

Making sense of anomalous gauge theories

An anomalous gauge theory is defined here as a gauge theory in which the field equation is inconsistent and gauge invariance is lost. A conventional approach to anomalous gauge theories, that of adjusting the fermion content so the anomaly vanishes, is discussed, followed by a mathematically coherent frame for anomalies. 10 refs. (LEW)
Date: September 1, 1985
Creator: Jackiw, R.
System: The UNT Digital Library
Polarization spectroscopy of tokamak plasmas (open access)

Polarization spectroscopy of tokamak plasmas

Measurements of polarization of spectral lines emitted by tokamak plasmas provide information about the plasma internal magnetic field and the current density profile. The methods of polarization spectroscopy, as applied to the tokamak diagnostic, are reviewed with emphasis on the polarimetry of motional Stark effect in hydrogenic neutral beam emissions. 25 refs., 7 figs.
Date: September 1, 1991
Creator: Wroblewski, D.
System: The UNT Digital Library
Hybrid reactors. [Fuel cycle] (open access)

Hybrid reactors. [Fuel cycle]

The rationale for hybrid fusion-fission reactors is the production of fissile fuel for fission reactors. A new class of reactor, the fission-suppressed hybrid promises unusually good safety features as well as the ability to support 25 light-water reactors of the same nuclear power rating, or even more high-conversion-ratio reactors such as the heavy-water type. One 4000-MW nuclear hybrid can produce 7200 kg of /sup 233/U per year. To obtain good economics, injector efficiency times plasma gain (eta/sub i/Q) should be greater than 2, the wall load should be greater than 1 MW.m/sup -2/, and the hybrid should cost less than 6 times the cost of a light-water reactor. Introduction rates for the fission-suppressed hybrid are usually rapid.
Date: September 9, 1980
Creator: Moir, Ralph W.
System: The UNT Digital Library
Probing the possibility of a /sup 12/C/sup 13/C abundance gradient from observations of interstellar CH/sup +/ (open access)

Probing the possibility of a /sup 12/C/sup 13/C abundance gradient from observations of interstellar CH/sup +/

I have performed high signal-to-noise (SN /equals/ 300 to 500) observations of interstellar CH/sup /plus// at Lick Observatory and at CTIO of the reddened, early-type stars HD 183143, HD 24432, and HD 157038 in an effort to probe the existence of a /sup 12/C/sup 13/C abundance gradient in our Galaxy.
Date: September 16, 1987
Creator: Hawkins, I.
System: The UNT Digital Library
Physical protection solutions for security problems at nuclear power plants. [PWR; BWR] (open access)

Physical protection solutions for security problems at nuclear power plants. [PWR; BWR]

Under Department of Energy sponsorship, Sandia National Laboratories has developed a broad technological base of components and integrated systems to address security concerns at facilities of importance, including nuclear reactors. The primary security concern at a light water reactor is radiological sabotage, a deliberate set of actions at a plant which could expose the public to a significant amount of radiation (on the order of 10 CFR 100 limits). (Also of importance to plant operators are acts of industrial sabotage that could prevent a plant from producing electrical power).
Date: September 1, 1980
Creator: Darby, J.L. & Jacobs, J.
System: The UNT Digital Library
A prototype on-line work procedure system for radioisotope thermoelectric generator production (open access)

A prototype on-line work procedure system for radioisotope thermoelectric generator production

An on-line system to manage work procedures is being developed to support radioisotope thermoelectric generator (RTG) assembly and testing in a new production facility. This system implements production work procedures as interactive electronic documents executed at the work site with no intermediate printed form. It provides good control of the creation and application of work procedures and provides active assistance to the worker in performing them and in documenting the results. An extensive prototype of this system is being evaluated to ensure that it will have all the necessary features and that it will fit the user's needs and expectations. This effort has involved the Radioisotope Power Systems Facility (RPSF) operations organization and technology transfer between Westinghouse Hanford Company (Westinghouse Hanford) and EG G Mound Applied Technologies Inc. (Mound) at the US Department of Energy (DOE) Mound Site. 1 ref.
Date: September 1, 1991
Creator: Kiebel, G.R.
System: The UNT Digital Library
Injection septum magnets for the Loma Linda medical accelerator (open access)

Injection septum magnets for the Loma Linda medical accelerator

The injection beamline runs over the last magnet before a long straight section and is then displaced downward 55.88 cm to the accelerator beamline. The displacement is magnetic and the final deflection onto the synchrotron orbit is by an electric kicker. The first component, the reverse septum magnet, bends the injection beam 25)degree) downward. This is followed by the injection septum (20)degree) bend upward) and the final injection kicker (5)degree) bend upward). The septum magnets produce a peak field of 3.4 K gauss at a current of 28,000 amperes within a 0.1 msec long pulse. The electric kicker produces a field of 7.3 KV/cm with a pulse length of 0.0011 msec. The septum magnets are similar to each other in construction with a bending radium of 72.7 cm. The curvature is required to increase the effective aperture. Each magnet has a single-turn copper coil bonded to a stainless steel plate for reinforcement. This eliminates insulating material, which could be subject to radiation damage, at the septum. The stainless steel plate is welded to the magnet laminations. The current is confined to the septum by the insulation between the laminations, which are a standard core material. The total septum thickness with …
Date: September 22, 1987
Creator: Satti, J.A.
System: The UNT Digital Library
The q q meson states with J sup PC = 2 sup ++ and 0 sup ++ (open access)

The q q meson states with J sup PC = 2 sup ++ and 0 sup ++

The lowest mesons made up of a light quark and a strange quark produced from a K beam show a good agreement with expectations of the quark model. This good agreement leads to the prediction of the light isoscalar and isovector states and the isoscalar s{bar s} states. Except for one mystery The X(1590) the 2{sup ++} states seems to be well described by the expected ideally mixed q{bar q} states up to 2. 0 GeV. Above 2.0 GeV a new degree of freedom seems to be excited with respect to the breakdown of the OZI rule in production of 2{sup ++} resonances that decay into {phi}{phi}. This is to be contrasted with the situation for the O{sup ++} isoscalar states which seems to show a new degree of freedom for its mesons in its ground state. One might conclude that since the O{sup ++} glueball is predicted by lattice calculations to be degenerate with the s{bar s} O{sup ++} meson, that the very unusual assortment of isoscalar O{sup ++} mesons are due to glueball mixing.
Date: September 26, 1991
Creator: Longacre, R. S.
System: The UNT Digital Library
Background field coils for the High Field Test Facility (open access)

Background field coils for the High Field Test Facility

The High Field Test Facility (HFTF), presently under construction at LLNL, is a set of superconducting coils that will be used to test 1-m-o.d. coils of prototype conductors for fusion magnets in fields up to 12 T. The facility consists of two concentric sets of coils; the outer set is a stack of Nb-Ti solenoids, and the inner set is a pair of solenoids made of cryogenically-stabilized, multifilamentary Nb/sub 3/Sn superconductor, developed for use in mirror-fusion magnets. The HFTF system is designed to be parted along the midplane to allow high-field conductors, under development for Tokamak fusion machines, to be inserted and tested. The background field coils were wound pancake-fashion, with cold-welded joints at both the inner and outer diameters. Turn-to-turn insulation was fabricated at LLNL from epoxy-fiberglass strip. The coils were assembled and tested in our 2-m-diam cryostat to verify their operation.
Date: September 22, 1980
Creator: Zbasnik, J. P.; Cornish, D. N.; Scanlan, R. M.; Jewell, A. M.; Leber, R. L.; Rosdahl, A. R. et al.
System: The UNT Digital Library
Panel discussion on laboratory accelerator programs: present and future (open access)

Panel discussion on laboratory accelerator programs: present and future

The present SLAC accelerator program is summarized briefly, and the future of electron-positron colliders is discussed. Present activities discussed include the PEP storage ring, the SPEAR storage ring, the Linear Accelerator, and the SLAC Linear Collider (SLC) project. Future prospects include a larger scale linear collider. The stability requirements on acceleration are briefly discussed. (LEW)
Date: September 1, 1986
Creator: Richter, B.
System: The UNT Digital Library
Ferrocyanide-containing waste tanks: Ferrocyanide chemistry and reactivity (open access)

Ferrocyanide-containing waste tanks: Ferrocyanide chemistry and reactivity

The complexing constant for hexacyano-iron complexes, both Fe(2) and Fe(3), are exceptionally large. The derived transition metal salts or double salts containing alkali metal ions are only slightly soluble. The various nickel compounds examined in this study, i.e., those predicted to have been formed in the Hanford waste scavenging program, are typical examples. In spite of their relative stability towards most reagents under ambient conditions, they are all thermodynamically unstable towards oxidation and react explosively with oxidants such as nitrate or nitrate salts when heated to temperatures in excess of 200{degree}C. 42 refs., 5 figs., 3 tabs.
Date: September 1, 1991
Creator: Scheele, R. D.; Burger, L. L.; Tingey, J. M.; Bryan, S. A.; Borsheim, G. L.; Simpson, B. C. et al.
System: The UNT Digital Library
Search for W prime and Z prime at CDF (open access)

Search for W prime and Z prime at CDF

We have searched for heavy charged and neutral vector bosons via the decays W{prime} {yields} ev, W{prime} {yields} {mu}v, Z{prime} {yields} {mu}{mu} in p{bar p} collisions at {radical}s = 1.8 TeV, using data taken with the collider Detector at Fermilab. The nonobservation of these processes leads to a lower limit (95% confidence level) of 520 GeV/c{sup 2} on the mass of the W{prime} and of 412 GeV/C{sup 2} on the mass of the Z{prime}, assuming standard model coupling to fermions. 12 refs., 6 figs., 1 tab.
Date: September 1, 1991
Creator: Fuess, T.
System: The UNT Digital Library
Oxide cathode lifetime improvements at RTNS-II (open access)

Oxide cathode lifetime improvements at RTNS-II

Results are reported for an ongoing effort to optimize D/sup +/ beam production by the MATS-III ion source used at the RTNS-II. The oxide cathode assembly originally designed for lower power operation has been modified and redesigned for higher electron current yield, longer life and serviceability. A factor of 2.5 has been gained in cathode lifetime due to these changes. The details of the changes and results and benefits in operation and performance are given. In addition, the technique used for manufacture of the filament is described.
Date: September 29, 1986
Creator: Massoletti, D.J.
System: The UNT Digital Library
The Scalable Coherent Interface and related standards projects (open access)

The Scalable Coherent Interface and related standards projects

The Scalable Coherent Interface (SCI) project (IEEE P1596) found a way to avoid the limits that are inherent in bus technology. SCI provides bus-like services by transmitting packets on a collection of point-to-point unidirectional links. The SCI protocols support cache coherence in a distributed-shared-memory multiprocessor model, message passing, I/O, and local-area-network-like communication over fiber optic or wire links. VLSI circuits that operate parallel links at 1000 MByte/s and serial links at 1000 Mbit/s will be available early in 1992. Several ongoing SCI-related projects are applying the SCI technology to new areas or extending it to more difficult problems. P1596.1 defines the architecture of a bridge between SCI and VME; P1596.2 compatibly extends the cache coherence mechanism for efficient operation with kiloprocessor systems; P1596.3 defines new low-voltage (about 0.25 V) differential signals suitable for low power interfaces for CMOS or GaAs VLSI implementations of SCI; P1596.4 defines a high performance memory chip interface using these signals; P1596.5 defines data transfer formats for efficient interprocessor communication in heterogeneous multiprocessor systems. This paper reports the current status of SCI, related standards, and new projects. 16 refs.
Date: September 1, 1991
Creator: Gustavson, D.B.
System: The UNT Digital Library
Open and hidden charm muoproduction. [209 GeV] (open access)

Open and hidden charm muoproduction. [209 GeV]

New results are presented on open and hidden charm and bottom production by 209-GeV muons interacting in a magnetized steel calorimeter. The upper limit on the production of T states by muons is sigma(..mu..N ..-->.. ..mu..UPSILONX)B(UPSILON ..-->.. ..mu mu..) < 22 x 10/sup -39/ cm/sup 2/ (90% confidence level). The distributions of elastically produced psi's are consistent with s-channel helicity conservation (SCHC) and disagree with psi dominance. From analysis of dimuon final states the cross section for diffractive charm muoproduction is 6.9/sub -1.4/sup +1.9/ nb. The structure function F/sub 2/(c anti c) for diffractive charmed-quark pair production is presented. 5 figures, 2 tables.
Date: September 1, 1980
Creator: Clark, A.R.; Johnson, K.J. & Kerth, L.T.
System: The UNT Digital Library
Some initial measurements of DDT resuspension and translocation from Pacific Northwest forests (open access)

Some initial measurements of DDT resuspension and translocation from Pacific Northwest forests

None
Date: September 1, 1974
Creator: Orgill, M M; Petersen, M R & Sehmel, G A
System: The UNT Digital Library
Bootstrap and fast wave current drive for tokamak reactors (open access)

Bootstrap and fast wave current drive for tokamak reactors

Using the multi-species neoclassical treatment of Hirshman and Sigmar we study steady state bootstrap equilibria with seed currents provided by low frequency (ICRF) fast waves and with additional surface current density driven by lower hybrid waves. This study applies to reactor plasmas of arbitrary aspect ratio. IN one limit the bootstrap component can supply nearly the total equilibrium current with minimal driving power (< 20 MW). However, for larger total currents considerable driving power is required (for ITER: I{sub o} = 18 MA needs P{sub FW} = 15 MW, P{sub LH} = 75 MW). A computational survey of bootstrap fraction and current drive efficiency is presented. 11 refs., 8 figs.
Date: September 1, 1991
Creator: Ehst, D.A.
System: The UNT Digital Library
Nuclear de-excitation processes following medium energy heavy ion collisions (open access)

Nuclear de-excitation processes following medium energy heavy ion collisions

As heavy ion reaction studies have progressed from beam energies below 10 MeV/nucleon to higher energies, many non-equilibrium reaction phenomena have been observed. Among these are nucleon emission with velocities in excess of the beam velocity, incomplete momentum transfer to evaporation residue and fission-like fragments, ..gamma..-rays with energies in excess of 100 MeV, and ..pi../sup 0/ production when beam energies are below the threshold for production by the nucleon-nucleon collision mechanism. Additionally, prefission neutrons have been observed in excess of numbers expected from equilibrium models. A few of the approaches which have been applied to these phenomena are as follows: Intranuclear cascade: two body collisions are assumed to mediate the equilibration. The geometry and momentum space is followed semiclassically. The approach has many successes though it may suffer in a few applications is not following holes; TDHF considers one body processes only; in the energy regime of interest, two body processes are important so that this may not be a viable approach; Boltzmann-Uehling-Uhlenbeck or Vlasov-Uehling-Uhlenbeck (BUU/VUU) equations combine both one body and two body dynamics. The spatial and momentum evolution of the reactions are followed in a mean field. These should be the Cadillacs of the models. They are computationally …
Date: September 1, 1986
Creator: Blann, M.
System: The UNT Digital Library
Operational history of Fermilab's 1500 W refrigerator used for energy saver magnet production testing (open access)

Operational history of Fermilab's 1500 W refrigerator used for energy saver magnet production testing

The 1500 W helium refrigerator system utilizes two oil-injected screw compressors staged to feed a liquid nitrogen pre-cooled cold box. Refrigeration is provided by two Sulzer TGL-22 magnetic/gas bearing turbines. The refrigerator feeds six magnet test stands via a 10,000 L dewar and subcooler equipped distribution box. The design of the controls has permitted the system to be routinely operated 24 hours/day, seven days/week with only five operators. It has operated approximately 90% of the 4-1/2 years prior to shutting down in 1984 for a period of one year to move the compressor skid. Scheduled maintenance, failures, repairs and holidays are about equal to the 10% off time. The equipment described was used to test approximately 1200 superconducting magnets for the Fermilab accelerator ring. The seven year operating experience is presented as an equipment and technique review. Compressor hours currently exceed 42,000 and turbine hours exceed 39,000 each. Failure rates, causes, preventive maintenance, monitoring practices and equipment, and modifications are examined along with notes on some of the more successful applications of technique and equipment. 4 refs.
Date: September 1, 1985
Creator: Bianchi, A. J.; Barger, R. K.; Johnson, F. B.; McGuire, K. J.; Pinyan, K. D.; Wilson, F. W. et al.
System: The UNT Digital Library
Positron computed tomography: current state, clinical results and future trends (open access)

Positron computed tomography: current state, clinical results and future trends

An overview is presented of positron computed tomography: its advantages over single photon emission tomography, its use in metabolic studies of the heart and chemical investigation of the brain, and future trends. (ACR)
Date: September 1, 1980
Creator: Schelbert, H. R.; Phelps, M. E. & Kuhl, D. E.
System: The UNT Digital Library
Polymer concrete patching materials (open access)

Polymer concrete patching materials

The increased use of deicing salts is causing rapid deterioration of portland cement concrete bridge decks. Soluble chlorides cause corrosion of the steel reinforcing rods with a corresponding increase in volume of the rods. This expansion causes stresses in the concrete which result in delaminations and surface spalling. The repair of surface spalls with portland cement concrete can only be made if traffic can be avoided for several days. A patching material which would allow traffic to resume over the repaired area in a few hours was needed. Polymer concrete (PC) was developed to repair deteriorated portland cement concrete. Polymer concrete is defined as a composite material in which the aggregate is bound together in a dense matrix with a polymer binder. The aggregate is mixed with a monomer mixture and subsequently cured in place. Polymer concrete combines the premix characteristics of portland cement concrete with high strength, long term durability properties and fast cure times. PC placed at temperatures between 35/sup 0/F and 95/sup 0/F attains strengths greater than 5000 psi in 2 hours. The high early strength of PC is suitable for use in the repair of highway structures where traffic conditions allow closing of the area for …
Date: September 1, 1977
Creator: Fontana, J.J.
System: The UNT Digital Library
Engineering design solutions of flux swing with structural requirements for ohmic heating solenoids (open access)

Engineering design solutions of flux swing with structural requirements for ohmic heating solenoids

Here a more detailed publication is summarized which presents analytical methods with solutions that describe the structural behavior of ohmic heating solenoids to achieve a better understanding of the relationships between the functional variables that can provide the basis for recommended design improvements. The solutions relate the requirements imposed by structural integrity to the need for producing sufficient flux swing to initiate a plasma current in the tokamak fusion machine. A method is provided to perform a detailed structural analysis of every conducting turn in the radial build of the solenoid, and computer programmed listings for the closed form solutions are made available as part of the reference document. Distinction is made in deriving separate models for the regions of the solenoid where turn-to-turn radial contact is maintained with radial compression or with a bond in the presence of radial tension, and also where there is turn-to-turn radial separation due to the absence or the loss of bonding in the presence of would be radial tension. The derivations follow the theory of elasticity for a body possessing cylindrical anisotropy where the material properties are different in the radial and tangential directions. The formulations are made practical by presenting the methods …
Date: September 30, 1977
Creator: Smith, R. A.
System: The UNT Digital Library
Pellet fueling development at ORNL (open access)

Pellet fueling development at ORNL

Advanced plasma fueling systems for magnetic confinement devices are being developed at the Oak Ridge National Laboratory (ORNL). The general approach is that of producing and accelerating frozen hydrogenic pellets at speeds in the range of 1-2 km/s and higher. Two specific concepts are under development: (1) high-speed pneumatic acceleration; and (2) mechanical (centrifugal) acceleration. Both approaches are being pursued to meet the projected pellet size and delivery rates for major near-term plasma confinement devices, such as the Tokamak Fusion Test Reactor (TFTR), Tore Supra, the Joint European Torus (JET), JT-60, and Doublet III-D (DIII-D), as well as future applications. In addition to these confinement physics related activities, ORNL is pursuing advanced technologies to achieve pellet velocities significantly in excess of the 2-km/s range already attained with pneumatic injectors and has embarked on a development program designed to explore the feasibility of fabricating and accelerating tritium pellets. This paper describes these ongoing activities.
Date: September 1, 1986
Creator: Combs, S. K.; Milora, S. L.; Foster, C. A.; Schuresko, D. D.; Foust, C. R.; Simmons, D. W. et al.
System: The UNT Digital Library
Proceedings of the 1986 workshop on advanced time-of-flight neutron powder diffraction (open access)

Proceedings of the 1986 workshop on advanced time-of-flight neutron powder diffraction

This report contains abstracts of talks and summaries of discussions from a small workshop held to discuss the future of time-of-flight neutron powder diffraction and its implementation at the Los Alamos Neutron Scattering Center. 47 refs., 3 figs.
Date: September 1, 1986
Creator: Lawson, A. C. & Smith, K. (comps.)
System: The UNT Digital Library