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Isentropic Compressibility of an Ideal Ternary Solution (open access)

Isentropic Compressibility of an Ideal Ternary Solution

Article on isentropic compressibility of an ideal ternary solution.
Date: April 1, 1983
Creator: Acree, William E. (William Eugene)
System: The UNT Digital Library
Efficient, radiation-hardened, 400- and 800-keV neutral-beam injection systems (open access)

Efficient, radiation-hardened, 400- and 800-keV neutral-beam injection systems

We present designs for two negative-ion based neutral beam lines with reactor-level power output. Both beam lines make use of such technologically advanced features as high-current-density surface-conversion ion sources, transverse-field-focussing (TFF) acceleration and transport, and laser photodetachment. For the second of these designs, we also presented detailed beam and vacuum calculations, as well as a brief description of a proof-of-principle test system currently under development.
Date: April 1, 1983
Creator: Anderson, O. A.; Cooper, W. S.; Fink, J. A.; Goldberg, D. A.; Ruby, L.; Soroka, L. et al.
System: The UNT Digital Library
Analysis of forward and near-forward elastic-scattering amplitudes for pp and anti pp collisions (open access)

Analysis of forward and near-forward elastic-scattering amplitudes for pp and anti pp collisions

We will present the results of two recently published (1983) papers by M.M. Block and R.N. Cahn, which analyze for anti pp and pp elastic scattering the rho values (ratios of the real to the imaginary parts of the forward nuclear scattering amplitudes), the total (hadronic) cross sections sigma, and the b values, the nuclear slope parameters. The predictions of the analyses, from ..sqrt.. s bar > 5 GeV, is compared with the recently measured values of sigma and b at the SPS Collider. The analysis has also been redone to include new ISR data available from R211 at ..sqrt.. s bar = 62.5 GeV, in order to estimate odderon contributions, i.e., contributions from odd amplitudes with unconventional (non-Reggeon) energy dependence. Limits of approx. 1% are placed on these amplitudes. Our analysis has been extrapolated up to 100 TeV, to give sigma, rho and b predictions for cosmic ray and future collider energies.
Date: April 1, 1983
Creator: Block, M.B. & Cahn, R.N.
System: The UNT Digital Library
Lattice dynamics of the mixed-conducting intermetallic compound,. beta. -LiAl (open access)

Lattice dynamics of the mixed-conducting intermetallic compound,. beta. -LiAl

The intermetallic compound, ..beta..-LiAl, that crystallizes in the uncommon Zintl structure is a mixed-conducting electrode and has many unusual properties pointing to the existence of unusual bonding in the semi-metallic compound. In order to elucidate the nature of the bonding in LiAl, we have studied the lattice dynamics of ..beta..-LiAl by inelastic neutron scattering. Results for the phonon dispersion curves have been obtained for the principal symmetry directions. A force constant fit to the results indicates that the Al-Al force constants are unusually large. Pair potentials were constructed by conventional pseudopotential calculations. The pair interactions favoring the Zintl structure were used to compute phonon dispersion curves. Good agreement between theory and experiment can be obtained for the acoustic branches.
Date: April 1, 1983
Creator: Brun, T.O.; Robinson, J.E.; Susman, S.; Mildner, D.F.R.; Dejus, R. & K., Skoeld
System: The UNT Digital Library
Effect of total pressure on graphite oxidation. [HTGR] (open access)

Effect of total pressure on graphite oxidation. [HTGR]

Graphite corrosion in the high-temperature gas-cooled reactor (HTGR) is calculated using two key assumptions: (1) the kinetic, catalysis, and transport characteristics of graphite determined by bench-scale tests apply to large components at reactor conditions and (2) the effects of high pressure and turbulent flow are predictable. To better understand the differences between laboratory tests and reactor conditions, a high-pressure test loop (HPTL) has been constructed and used to perform tests at reactor temperature, pressure, and flow conditions. The HPTL is intended to determine the functional dependence of oxidation rate and characteristics on total pressure and gas velocity and to compare the oxidation results with calculations using models and codes developed for the reactor.
Date: April 1, 1983
Creator: Burnette, R. D. & Hoot, C. G.
System: The UNT Digital Library
Search for right-handed currents in muon decay (open access)

Search for right-handed currents in muon decay

We report new limits on right-handed currents, based on precise measurement of the endpoint of the e/sup +/ spectrum from ..mu../sup +/ decay. Highly polarized ..mu../sup +/ from the TRIUMF surface beam were stopped in pure metal foils within either an 1.1-T spin-holding longitudinal field, or a 70-gauss spin-precessing transverse field. Decay e/sup +/ emitted within 200 mrad of the beam direction were momentum-analyzed to +-0.2%. For the spin-held data, decay via (V-A) currents requires the e/sup +/ rate to approach zero in the beam direction at the endpoint. Measurement of this rate sets the 90% confidence limits xi P/sub ..mu../delta/rho > 0.9959 and M(W/sub R/) > 380 GeV, where W/sub R/ is the possible right-handed gauge boson. For the spin-precessed data we independently determine a 90% confidence limit xi P/sub ..mu../delta/rho > 0.9918. 18 references.
Date: April 1, 1983
Creator: Carr, J.; Gidal, G.; Gobbi, B.; Jodidio, A.; Oram, C. J.; Shinsky, K. A. et al.
System: The UNT Digital Library
Mechanical engineering aspects of TFTR (open access)

Mechanical engineering aspects of TFTR

This paper briefly presents the principles which characterize a tokamak and discusses the mechanical aspects of TFTR, particularly the toroidal field coils and the vacuum chamber, in the context of being key components common to all tokamaks. The mechanical loads on these items as well as other design requirements are considered and the solutions to these requirements as executed in TFTR are presented. Future technological developments beyond the scope of TFTR, which are necessary to bring the tokamak concept to a full fusion-power system, are also presented. Additional methods of plasma heating, current drive, and first wall designs are examples of items in this category.
Date: April 1, 1983
Creator: Citrolo, J.C.
System: The UNT Digital Library
Zero-field. mu. SR and low-temperature. mu. /sup +/ diffusivity in copper (open access)

Zero-field. mu. SR and low-temperature. mu. /sup +/ diffusivity in copper

In this paper the history of ..mu../sup +/ diffusion studies in copper, with particular emphasis on the increased low-temperature diffusivity which has been known for several years now, is reviewed. The theory and practice of the zero-field ..mu..SR method, which has come into increasing favor in the study of muon diffusion and trapping in metals, is surveyed, and its application to the low-temperature copper problem is discussed. 26 references.
Date: April 1, 1983
Creator: Clawson, C.W.
System: The UNT Digital Library
Effects of electronically neutral impurities on muonium in germanium (open access)

Effects of electronically neutral impurities on muonium in germanium

Low-temperature measurements of muonium parameters in various germanium crystals have been performed. We have measured crystals with different levels of neutral impurities, with and without dislocations, and with different annealing histories. The most striking result is the apparent trapping of Mu by silicon impurities in germanium.
Date: April 1, 1983
Creator: Clawson, C.W.; Crowe, K.M.; Haller, E.E.; Rosenblum, S.S. & Brewer, J.H.
System: The UNT Digital Library
Isotropy of ultra-high-energy cosmic rays and multiple supernova I galactic source (open access)

Isotropy of ultra-high-energy cosmic rays and multiple supernova I galactic source

Ultra-high-energy cosmic rays are usually associated with an extragalactic origin. Active galactic nuclei are an unlikely source because of photon drag. Here the possibility of supernova events are considered. The time spread of arrival of 10/sup 20/ eV protons is 100 to 400 years at 10 to 20 kpc and the angular spread is +-15 to +-30/sup 0/ depending upon the Galactic field configuration. The time spread is sufficient to include several to a dozen type I SN. This is enough events and angular spread to include the observed data. The concentration of the observed events at the galactic poles is contradictory. The flux is reasonable if the observed flux and slope at 10/sup 12/ to 10/sup 15/ eV is characteristic of the source(s) and confined at this energy for roughly 100 traversals of the Galaxy, or 3 x 10/sup 6/ years.
Date: April 7, 1983
Creator: Colgate, S. A.
System: The UNT Digital Library
Photon damping in cosmic-ray acceleration in active galactic nuclei (open access)

Photon damping in cosmic-ray acceleration in active galactic nuclei

The usual assumption of the acceleration of ultra high energy cosmic rays, greater than or equal to 10/sup 18/ eV in quasars, Seyfert galaxies and other active galactic nuclei is challenged on the basis of the photon interactions with the accelerated nucleons. This is similar to the effect of the black body radiation on particles > 10/sup 20/ eV for times of the age of the universe except that the photon spectrum is harder and the energy density greater by approx. = 10/sup 15/. Hence, a single traversal, radial or circumferential, of radiation whose energy density is no greater than the emitted flux will damp an ultra high energy. Hence, it is unlikely that any reasonable configuration of acceleration can void disastrous photon energy loss. A different site for ultra high energy cosmic ray acceleration must be found.
Date: April 7, 1983
Creator: Colgate, S. A.
System: The UNT Digital Library
Lattice gauge theories (open access)

Lattice gauge theories

In the last few years lattice gauge theory has become the primary tool for the study of nonperturbative phenomena in gauge theories. The lattice serves as an ultraviolet cutoff, rendering the theory well defined and amenable to numerical and analytical work. Of course, as with any cutoff, at the end of a calculation one must consider the limit of vanishing lattice spacing in order to draw conclusions on the physical continuum limit theory. The lattice has the advantage over other regulators that it is not tied to the Feynman expansion. This opens the possibility of other approximation schemes than conventional perturbation theory. Thus Wilson used a high temperature expansion to demonstrate confinement in the strong coupling limit. Monte Carlo simulations have dominated the research in lattice gauge theory for the last four years, giving first principle calculations of nonperturbative parameters characterizing the continuum limit. Some of the recent results with lattice calculations are reviewed. (WHK)
Date: April 1, 1983
Creator: Creutz, M.
System: The UNT Digital Library
Computation of self-consistent 2-D MHD with neutral-beam and bootstrap currents in elongated plasmas (open access)

Computation of self-consistent 2-D MHD with neutral-beam and bootstrap currents in elongated plasmas

The observation of substantial current drive from neutral beam injection (NBI) in TFTR, JET and DIII-D has led to renewed interest in a steady state, non-inductively driven tokamak. The discovery of apparently considerable neoclassical (bootstrap) current in TFTR, makes a steady state device even more attractive since the bootstrap portion of the current could be obtained without additional power input. Motivated by these results, we have developed a code, ACCOME, which self-consistently computes the 2-D MHD equilibrium with the current driven by neutral beams, bootstrap and the electric field. In this paper we first describe some details of the code in the next section and in the subsequent section show some applications to DIII-D and to a possible ITER design.
Date: April 5, 1983
Creator: Devoto, R. S.; Tani, K. & Azumi, M.
System: The UNT Digital Library
High-spin. gamma. -ray spectroscopy: past successes, future hopes (open access)

High-spin. gamma. -ray spectroscopy: past successes, future hopes

Nuclei can carry angular momentum by aligning individual particles along the rotation axis or by rotation of a deformed nucleus as a whole. The interweaving of these modes leads to a variety of behavior that is just beginning to be observed and explained. The discrete ..gamma..-ray studies have led to a new backbending spectroscopy, which is telling us about the details of particle alignments and monopole and quadrupole pairing. The high-spin continuum studies, as yet less well developed, are indicating changes in shape and structure, as well as particle alignments from higher shells. New developments in detector systems and in theory promise much more detailed comparisons of experiment and theory and consequent increase in our knowledge of nuclear behavior at high spin.
Date: April 1, 1983
Creator: Diamond, R. M.
System: The UNT Digital Library
e/sup +/e/sup -/ interactions at very high energy: searching beyond the standard model (open access)

e/sup +/e/sup -/ interactions at very high energy: searching beyond the standard model

These lectures discuss e/sup +/e/sup -/ interactions at very high energies with a particular emphasis on searching the standard model which we take to be SU(3)/sub color/..lambda.. SU(2) ..lambda.. U(1). The highest e/sup +/e/sup -/ collision energy exploited to date is at PETRA where data have been taken at 38 GeV. We will consider energies above this to be the very high energy frontier. The lectures will begin with a review of the collision energies which will be available in the upgraded machines of today and the machines planned for tomorrow. Without going into great detail, we will define the essential elements of the standard model. We will remind ourselves that some of these essential elements have not yet been verified and that part of the task of searching beyond the standard model will involve experiments aimed at this verification. For if we find the standard model lacking, then clearly we are forced to find an alternative. So we will investigate how the higher energy e/sup +/e/sup -/ collisions can be used to search for the top quark, the neutral Higgs scalar, provide true verification of the non-Abelian nature of QCD, etc. Having done this we will look at tests …
Date: April 1, 1983
Creator: Dorfan, J.
System: The UNT Digital Library
Driver options and burn-cycle selection based on power-reactor considerations (open access)

Driver options and burn-cycle selection based on power-reactor considerations

Reactor implications for noninductive current drive are presented based on a number of studies. First, the lower hybrid driver for the STARFIRE reactor is discussed and the disadvantages of this driver are reviewed. Next, the results of an extensive search for a better current driver are presented. A large number of alternatives were compared in a common context, the DEMO reactor, in order to examine their suitability on a standard basis. Finally, the methodology of a study, currently in progress, is described. The goals of this last study are to compare tokamak reactor designs optimized for operation under different burn cycles, in order to assess the actual benefits and costs of pulsed versus steady-state operation.
Date: April 1, 1983
Creator: Ehst, D.A.
System: The UNT Digital Library
Theoretical perspectives on strange physics (open access)

Theoretical perspectives on strange physics

Kaons are heavy enough to have an interesting range of decay modes available to them, and light enough to be produced in sufficient numbers to explore rare modes with satisfying statistics. Kaons and their decays have provided at least two major breakthroughs in our knowledge of fundamental physics. They have revealed to us CP violation, and their lack of flavor-changing neutral interactions warned us to expect charm. In addition, K/sup 0/-anti K/sup 0/ mixing has provided us with one of our most elegant and sensitive laboratories for testing quantum mechanics. There is every reason to expect that future generations of kaon experiments with intense sources would add further to our knowledge of fundamental physics. This talk attempts to set future kaon experiments in a general theoretical context, and indicate how they may bear upon fundamental theoretical issues. A survey of different experiments which would be done with an Intense Medium Energy Source of Strangeness, including rare K decays, probes of the nature of CP isolation, ..mu.. decays, hyperon decays and neutrino physics is given. (WHK)
Date: April 1, 1983
Creator: Ellis, J.
System: The UNT Digital Library
Issues in the standard model (open access)

Issues in the standard model

Focussing on the standard electroweak model, we examine physics issues which may be addressed with the help of intense beams of strange particles. I have collected miscellany of issues, starting with some philosophical remarks on how things stand and where we should go from here. I will then focus on a case study: the decay K/sup +/ ..-->.. ..pi../sup +/ + nothing observable, which provides a nice illustration of the type of physics that can be probed through rare decays. Other topics I will mention are CP violation in K-decays, hyperon and anti-hyperon physics, and a few random comments on other relevant phenomena.
Date: April 1, 1983
Creator: Gaillard, M. K.
System: The UNT Digital Library
Evaporation of mesons from quark-gluon plasma by fission of chromoelectric flux tubes (open access)

Evaporation of mesons from quark-gluon plasma by fission of chromoelectric flux tubes

The chromoelectric flux tube model is used to obtain a dynamical description of the evaporation of mesons from a quark-gluon plasma. The radiation pressure is computed to assess whether this process is an important mode for the disassembly of a compressed plasma. A new result for the creation rate of q anti q pairs in a constant color field is employed.
Date: April 1, 1983
Creator: Glendenning, N.K.; Banerjee, B. & Matsui, T.
System: The UNT Digital Library
Some observations on simulated molten debris-coolant layer dynamics. [PWR; BWR] (open access)

Some observations on simulated molten debris-coolant layer dynamics. [PWR; BWR]

Experiments are being performed to investigate high temperature liquid-liquid film boiling between a pool of liquid metal and an overlying coolant pool of R-11 or water. Film boiling has been observed to be stable for R-11; however, considerable liquid-liquid contact has been observed with water well beyond the minimum film boiling temperature. Unstable liquid-liquid film boiling of water has been observed to escalate into dispersive, non-energetic vapor explosions when the interface contact temperature exceeded the spontaneous nucleation temperature. Other parametric trends in the data are discussed.
Date: April 1, 1983
Creator: Greene, G.A.; Klein, J.; Klages, J.; Schwarz, E. & Sanborn, Y.
System: The UNT Digital Library
Effects of radiation on frequency of chromosomal aberrations and sister chromatid exchange in the benthic worm Neanthes arenaceodentata (open access)

Effects of radiation on frequency of chromosomal aberrations and sister chromatid exchange in the benthic worm Neanthes arenaceodentata

Traditional bioassays are unsuitable for assessing sublethal effects of low levels of radioactivity because mortality and phenotypic responses are not anticipated. We compared the usefulness of chromosomal aberration (CA) and sister chromatid exchange (SCE) induction as measures of low-level radiation effects in a sediment-dwelling marine worm, Neanthes arenaceodentata. Newly hatched larvae were exposed to two radiation exposure regimes. Groups of 100 larvae were exposed to either x rays delivered at high dose rates (0.7 Gy min/sup -1/) or to /sup 60/Co gamma rays delivered at low dose rates (4.8 X 10/sup -5/ to 1.2 X 10/sup -1/ Gy h/sup -1/). After irradiation, the larvae were exposed to 3 X 10/sup -5/M bromodeoxyuridine (BrdUrd) for 28 h (x-ray-irradiated larvae) or for 54 h (/sup 60/Co-irradiated larvae). Slides of larval cells were prepared for observation of CAs and SCEs. Frequencies of CAs were determined in first division cells; frequencies of SCEs were determined in second division cells. Results from x-ray irradiation indicated that dose-related increases occur in chromosome and chromatid deletions, but an x-ray dose greater than or equal to 2 Gy was required to observe a significant increase. Worm larvae receiving /sup 60/Co irradiation showed elevated SCE frequencies; a significant increase …
Date: April 1, 1983
Creator: Harrison, Florence L.; Rice, David W., Jr.; Moore, Dan H. & Varela, Marilyn
System: The UNT Digital Library
Results of railgun experiments (open access)

Results of railgun experiments

During the 1979 Megagauss II conference the hypervelocity potential of railguns and the pulsed power technology needed to power them were discussed. Since then, many laboratories have initiated railgun R and D projects for a variety of potential applications. Los Alamos and Lawrence Livermore National Laboratories initiated a collaborative experimental railgun project which resulted in several successes in accelerating projectiles to high velocities, emphasized the limits on railgun operation, and indicated that the numerical modeling of railgun operation was in good agreement with the experiments.
Date: April 1, 1983
Creator: Hawke, R. S.; Brooks, A. L.; Fowler, C. M. & Peterson, D. R.
System: The UNT Digital Library
New developments in heavy ion fusion (open access)

New developments in heavy ion fusion

Beginning in 1984, the US Department of Energy plans a program aimed at determining the feasibility of using heavy ion accelerators as pellet drivers for Inertial Confinement Fusion (ICF). This paper will describe the events in the field of Heavy Ion Fusion (HIF) that have occurred in the three years since the Lausanne conference in this series. The emphasis will be on the events leading towards the new energy oriented program. in addition to providing an overview of progress in HIF, such a discussion may prove useful for promoters of any emerging energy technology.
Date: April 1, 1983
Creator: Herrmannsfeldt, W.B.
System: The UNT Digital Library
Sandia photovoltaic systems definition and application experiment projects (open access)

Sandia photovoltaic systems definition and application experiment projects

A compilation is given of the abstracts and visual material used in presentation at the Fourth Photovoltaic Systems Definition and Applications Projects Integration Meeting held at the Marriott Hotel, April 12-14, 1983, in Albuquerque, New Mexico. The meeting provided a forum for detailed analyses on recently completed and current activities. These activities include systems research, balance-of-system technology development, residential experimentation, and evaluation of intermediate-sized applications.
Date: April 1, 1983
Creator: Jones, G.
System: The UNT Digital Library