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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
Laser Accelerators (open access)

Laser Accelerators

Laser accelerators may be conveniently characterized, by their mode of operation, into media, far-field, and near-field accelerators. The first category--media accelerators--include the Inverse Cherenkov Effect Accelerator, the Plasma Focus Accelerator, and the Beat Wave Accelerator (BWA). The second category--far-field accelerators--include the Two-Wave Device and the Inverse Free Electron Accelerator (IFEL). The third category--near-field accelerators--includes conventional linacs scaled to small dimensions, dielectric sheets, small holes in dielectric cylinders, and gratings. Attention is devoted to an example from each category: namely (1) the BWA, (2) the IFEL, and (3) the linac scaled to small dimensions (about 30 GHz) and powered by a free electron laser (FEL). Finally, special attention is given to grating accelerators.
Date: April 1, 1983
Creator: Sessler, Andrew M.
System: The UNT Digital Library
PROCEEDINGS OF THE 1983 DPF WORKSHOP ON COLLIDER DETECTORS: PRESENT CAPABILITIES AND FUTURE POSSIBILITIES, FEB. 28 - MARCH 4, 1983. (open access)

PROCEEDINGS OF THE 1983 DPF WORKSHOP ON COLLIDER DETECTORS: PRESENT CAPABILITIES AND FUTURE POSSIBILITIES, FEB. 28 - MARCH 4, 1983.

It is useful before beginning our work here to restate briefly the purpose of this workshop in the light of the present circumstances of elementary particle physics in the U.S. The goal of our field is easily stated in a general way: it is to reach higher center of mass energies and higher luminosities while employing more sensitive and more versatile event detectors, all in order to probe more deeply into the physics of elementary particles. The obstacles to achieving this goal are equally apparent. Escalating costs of construction and operation of our facilities limit alternatives and force us to make hard choices among those alternatives. The necessity to be highly selective in the choice of facilities, in conjunction with the need for increased manpower concentrations to build accelerators and mount experiments, leads to complex social problems within the science. As the frontier is removed ever further, serious technical difficulties and limitations arise. Finally, competition, much of which is usually healthy, now manifests itself with greater intensity on a regional basis within our country and also on an international scale. In the far ({ge}20 yr) future, collaboration on physics facilities by two or more of the major economic entities of …
Date: April 1, 1983
Creator: Loken Ed, S.C. & Nemethy Ed, P.
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
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
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
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
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
Statistical calculation of complete events in medium-energy nuclear collisions (open access)

Statistical calculation of complete events in medium-energy nuclear collisions

This lecture presents the essential tools for formulating a statistical model for the nuclear disassembly process. We consider the quick disassembly (explosion) of a hot nuclear system, a so-called source, into multifragment final states, which compete according to their statistical weight. First some useful notation is introduced. The expressions for exclusive and inclusive distributions are given and the factorization of an exclusive distribution into inclusive ones is carried out. In turn, the grand canonical approximation for one-fragment inclusive distributions is introduced. Finally, it is outlined how to generate a statistical sample of complete final states. On this basis, a model for statistical simulation of complete events in medium-energy nuclear collisions has been developed.
Date: April 1, 1983
Creator: Randrup, J.
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
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
Nucleon-nucleon scattering contribution to the triton binding energy (open access)

Nucleon-nucleon scattering contribution to the triton binding energy

We conjectured in 1972 that much of the dynamics of a few nucleon systems could be computed from the on-shell nucleon-nucleon scatterings provided that a consistent few body theory using this input could be constructed. Such a Zero Range Scattering Theory has been shown to lead to unitary three and four particle scattering amplitudes provided only the two particle amplitudes have no singularities other than bound state poles when continued to negative energies, which restricts the theory to Castillejo-Dalitz-Dyson solutions of the Low equation. We extend the model by rewriting the off-shell amplitude which drives the Faddeev equations. This amplitude retains full off-shell unitarity and still leads to unitary on-shell three particle amplitudes. This amounts to keeping any unitary two-nucleon amplitude on-shell and restricting the analytic continuation to negative energies to the term which represents the correct continuation of the two particle total partial wave cross section; the meson exchange or potential contributions are eliminated in the unphysical region, thus excising the left-hand cut. Using this model in the zero range Faddeev equations for the three nucleon system our preliminary results show that the on-shell scatterings bind the triton with about 2.5 MeV and are insensitive to the details of …
Date: April 1, 1983
Creator: Noyes, H. Pierre
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
Status and future plans for the Mark II detector at SLAC (open access)

Status and future plans for the Mark II detector at SLAC

In this brief talk, I report on three subjects. First the present status of PEP, where there has been a very large increase in the luminosity in the past five months. Next, the present status of the Mark II detector, whose secondary vertex detector constitutes a very important part of the physics which our collaboration is doing at PEP. Finally, I review the design of the upgraded Mark II Detector which will be used at the Stanford Linear Collider (SLC).
Date: April 1, 1983
Creator: Perl, Martin L.
System: The UNT Digital Library
Interplays of. mu. SR, susceptibility, and neutron studies on dilute-alloy spin glasses (open access)

Interplays of. mu. SR, susceptibility, and neutron studies on dilute-alloy spin glasses

Static spin polarization of Fe moments in a spin glass AuFe, determined by zero-field ..mu..SR, is compared to an ac-susceptibility measurement below the cusp temperature T/sub g/, and a rather uniform amplitude of the static polarization is pointed out for frozen spins. Completely random orientation of frozen spins is revealed by neutron scattering in a dilute 1% CuMn, and an importance of comparing results of these different methods is demonstrated.
Date: April 1, 1983
Creator: Uemura, Y.J.
System: The UNT Digital Library
Diffractive dissociation and new quarks (open access)

Diffractive dissociation and new quarks

We argue that the chiral limit of QCD can be identified with the strong (diffractive dissociation) coupling limit of reggeon field theory. Critical Pomeron scaling at high energy must then be directly related to an infra-red fixed-point of massless QCD and so requires a large number of flavors. This gives a direct argument that the emergence of diffraction-peak scaling, KNO scaling etc. at anti p-p colliders are evidence of a substantial quark structure still to be discovered.
Date: April 1, 1983
Creator: White, A.R.
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
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
Resonance production in. gamma gamma. collisions (open access)

Resonance production in. gamma gamma. collisions

The processes ..gamma gamma.. ..-->.. hadrons can be depicted as follows. One photon creates a q anti q pair which starts to evolve; the other photon can either (A) make its own q anti q pair and the (q anti q q anti q) system continue to evolve or (B) interact with the quarks of the first pair and lead to a modified (q anti q) system in interaction with C = +1 quantum numbers. A review of the recent theoretical activity concerning resonance production and related problems is given under the following headings: hadronic C = +1 spectroscopy (q anti q, qq anti q anti q, q anti q g, gg, ggg bound states and mixing effects); exclusive ..gamma gamma.. processes (generalities, unitarized Born method, VDM and QCD); total cross section (soft and hard contributions); q/sup 2/ dependence of soft processes (soft/hard separation, 1/sup +- +/ resonances); and polarization effects. (WHK)
Date: April 1, 1983
Creator: Renard, F.M.
System: The UNT Digital Library
Collider detectors: present capabilities and future possibilities (open access)

Collider detectors: present capabilities and future possibilities

Separate abstracts were prepared for 27 papers in this conference proceedings. Thirteen other papers had been previously abstracted for EDB. (LEW)
Date: April 1, 1983
Creator: Loken, S.C. & Nemethy, P. (eds.)
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
Proceedings of the fifth symposium on training of nuclear facility personnel (open access)

Proceedings of the fifth symposium on training of nuclear facility personnel

Separate abstracts were prepared for 22 papers in this symposium proceedings. (LEW)
Date: April 1, 1983
Creator: unknown
System: The UNT Digital Library
Status of the iota (1440) and theta (1640) as gluonium candidates (open access)

Status of the iota (1440) and theta (1640) as gluonium candidates

A review of the experimental evidence for the iota (1440) and theta (1640) states is presented. The measured properties of these states are compared with various theoretical predictions. A likely interpretation is that these states contain a large gluonic admixture.
Date: April 1, 1983
Creator: Lockman, W.S.
System: The UNT Digital Library