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Human somatic, germinal and heritable mutagenicity

Description: This report deals with the general process of variant formation rather than with the consequences of a specific variant being present. It focusses on mutational mechanisms, mutagens, and the method for detecting de novo mutants and estimating mutation rate. It is to human genetics much like disease causation and prevention medicine are to medicine as a whole. The word ''mutagenicity'' is used in the title and throughout the text to connote the causation of all classes of genetic damage. Mutagen… more
Date: May 1, 1987
Creator: Mendelsohn, M.L.
Partner: UNT Libraries Government Documents Department
open access

The numerical simulation of accelerator components

Description: The techniques of the numerical simulation of plasmas can be readily applied to problems in accelerator physics. Because the problems usually involve a single component ''plasma,'' and times that are at most, a few plasma oscillation periods, it is frequently possible to make very good simulations with relatively modest computation resources. We will discuss the methods and illustrate them with several examples. One of the more powerful techniques of understanding the motion of charged particle… more
Date: May 1, 1987
Creator: Herrmannsfeldt, W.B. & Hanerfeld, H.
Partner: UNT Libraries Government Documents Department
open access

Progress toward identification of gluonic states

Description: Progress in the last two years toward identification of gluonic states is reviewed. Discovery of additional pseudoscalars tends to confirm the glueball interpretation of iota(1460). A variety of evidence indicates new physics in the J = 1 channel in the E mass region. 65 refs., 1 tab.
Date: May 29, 1987
Creator: Chanowitz, Michael S.
Partner: UNT Libraries Government Documents Department
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Improving Hatchery Effectiveness as Related to Smoltification: Proceedings of a Workshop held at Kah-Nee-Tah Lodge, Warm Springs, Oregon, May 20-23, 1985.

Description: The Bonneville Power Administration (BPA) intends to develop a smoltification research effort that would have broad support among the interested parties. BPA sponsored this workshop on smoltification and related research to gather leading technical experts in the field in smoltification, permit them to exchange information about the state of the art of smoltification research, and allow them to identify and rank high-priority projects. This document includes keynote speeches, technical papers, … more
Date: May 1, 1987
Creator: Bouck, Gerald R.
Partner: UNT Libraries Government Documents Department
open access

Blown-up orbifolds

Description: A method to repair - ''blow-up'' - the singularities of the Abelian (2,2) orbifolds to obtain the corresponding (2,2) Calabi-Yau manifolds is presented. This approach makes use of the fact that with each orbifold singularity there are associated massless scalar fields - blowing-up modes - whose potential is flat to all orders in the string perturbation theory. The zero vacuum expectation values (VEV's) of the blowing-up modes correspond to the orbifold limit, while nonzero VEV's yield the corre… more
Date: May 1, 1987
Creator: Cvetic, M.
Partner: UNT Libraries Government Documents Department
open access

Relativistic 3-D nuclear hydrodynamics with Monte Carlo pions

Description: A model for relativistic three-dimensional hydrodynamical nuclear fluids has been coupled to a Monte Carlo pion model which treats the production, scattering, and absorption of pions in relativistic nuclear fluids. The model is dynamic and allows us to explicitly follow the temporal and spatial development of pion components through an entire collision process and into the final state. Such calculations will be necessary to extract meaningful information from measured RHIC pion distributions. W… more
Date: May 1, 1987
Creator: Zingman, J. A.; McAbee, T. L.; Wilson, J. R. & Alonso, C. T.
Partner: UNT Libraries Government Documents Department
open access

Effect of Dy additions on microstructure and magnetic properties of Fe-Nd-B magnets

Description: It is shown that increasing additions of Dy causes the remanence B/sub r/ to decrease linearly. The intrinsic coercivity, iHc, increases sharply for small additions of Dy, but the increase is not proportional for higher Dy contents. The iHc increases almost linearly with the effective anisotropy field of the RE/sub 2/Fe/sub 14/B phase until the Dy content is about 10% of the total rare earth content. Above this concentration, there is strong deviation from linearity. Various types of possible c… more
Date: May 1, 1987
Creator: Ramesh, R.; Thomas, G. & Ma, B.M.
Partner: UNT Libraries Government Documents Department
open access

Exotic damping ring lattices

Description: This paper looks at, and compares three types of damping ring lattices: conventional, wiggler lattice with finite ..cap alpha.., wiggler lattice with ..cap alpha.. = 0, and observes the attainable equilibrium emittances for the three cases assuming a constraint on the attainable longitudinal impedance of 0.2 ohms. The emittance obtained are roughly in the ratio 4:2:1 for these cases.
Date: May 1, 1987
Creator: Palmer, Robert B.
Partner: UNT Libraries Government Documents Department
open access

Cryogenic detection of particles: Development effort in the United States

Description: The development of cryogenic detectors of particles, with emphasis on large mass devices, has been reviewed. Most groups are still tooling up and exploring basic properties of sensors. The main discussion themes are summarized and some of the early experimental results are described.
Date: May 1, 1987
Creator: Sadoulet, B.
Partner: UNT Libraries Government Documents Department
open access

Is Dark Matter made out of particles. Current searches and detector developments

Description: The hypothesis that Dark Matter is made out of exotic particles is definite enough to be testable in a variety of ways. We review the first generation experiments looking for dark matter particles, using conventional techniques. They may find those particles and in any case will provide powerful constraints. We argue that in the long run, cryogenic detectors will have to be used for that type of physics, and since the European effort is covered by other speakers, we review the present developme… more
Date: May 1, 1987
Creator: Sadoulet, B.
Partner: UNT Libraries Government Documents Department
open access

Use of permanent magnets in accelerator technology: Present and future

Description: This report is a collection of viewgraphs discussing accelerator magnets. Permanent magnet systems have some generic properties that, under some circumstances, make them not only mildly preferable over electromagnets, but make it possible to do things that can not be done with any other technology. After a general discussion of these generic advantages, some specific permanent magnet systems will be described. Special emphasis will be placed on systems that have now, or are likely to have in th… more
Date: May 1, 1987
Creator: Halbach, K.
Partner: UNT Libraries Government Documents Department
open access

Proceedings of the 1986 summer workshop on antiproton beams in the 2-10 GeV/c range

Description: The possibilities for building a facility for the formation spectroscopy of ''charmonium'' and the study of ''exotics'' at the AGS with high intensity antiproton beams of good resolution and enhanced purity are explored. The performance potential of a number of long beams and the AGS booster are evaluated and costs are estimated. Fluxes of several 10/sup 7/ antiprotons per pulse with purities of 5% to 99% are possible with conventional long beams. A similar total antiproton flux would be availa… more
Date: May 7, 1987
Creator: Lazarus, D. (ed.)
Partner: UNT Libraries Government Documents Department
open access

Geology of Platanares geothermal area, Copan, Honduras

Description: The Platanares, Copan (Honduras) geothermal area is located in a highly faulted terrain of Paleozoic(.) metamorphic rocks, Cretaceous clastic sedimentary rocks, and Tertiary volcanic rocks. All thermal manifestations are located along faults. The volcanic rocks are probably too old to represent the surface expression of an active crustal magma body. Thus, the thermal water is interpreted to be heated during deep circulation in a regime of elevated heat flow. The water chemistry suggests that th… more
Date: May 1, 1987
Creator: Heiken, G.; Duffield, W.; Wohletz, K.; Priest, S.; Ramos, N.; Flores, W. et al.
Partner: UNT Libraries Government Documents Department
open access

Search for close-mass lepton pairs (L/sup -/,L/sup 0/)

Description: Preliminary results are reported of a search in 207 pb/sup -1/ of MARK II PEP data at ..sqrt..s = 29 GeV for lepton pairs (L/sup -/,L/sup 0/) where the L/sup 0/ mass can be close to, but not exceed, the L/sup -/ mass. The numbers of e - ..mu.., and 3 or more charged hadrons versus isolated e or ..mu.., events are compared to Monte Carlo predictions for e/sup +/e/sup -/ ..-->.. tau/sup +/tau/sup -/, e/sup +/e/sup -/ ..-->.. q anti q, and two-virtual-photon processes. Possible residual signals fo… more
Date: May 1, 1987
Creator: Stoker, D. P. & Perl, M. L.
Partner: UNT Libraries Government Documents Department
open access

The influence of N-ion irradiation on superconducting TiN

Description: The influence of disorder on the properties of the B1 phase superconductive compound titanium nitride has been investigated. Following synthesis and characterization of thin films of TiN, the materials were disordered progressively and uniformly by irradiation with nitrogen ions. The superconducting transition temperature T/sub c/ decreased and the low temperature electrical resistivity rho increased as lattice damage was introduced. The dependence of both T/sub c/ and rho on N-ion fluence phi … more
Date: May 1, 1987
Creator: Thompson, J. R.; Ellis, J. T.; Christen, D. K.; Sekula, S. T.; Lewis, J. D. & Williams, J. M.
Partner: UNT Libraries Government Documents Department
open access

Probability of causation: Implications for radiological protection and dose limitation

Description: This report on the probability of causation of radiation-induced cancer is an attempt to bring together biology, chemistry, physics and statistics to calculate a value in the form of a ratio expressed as a percentage. In involves the interactions of numerous cancer risk factors, and all are fraught with technical difficulties and uncertainties. It is a computational approach to a societal problem that should be resolved in the political arena by men and women of government and law. But, it must… more
Date: May 1, 1987
Creator: Fabrikant, Jacob I.
Partner: UNT Libraries Government Documents Department
open access

Multifragmentation and flow in central collisions of heavy systems

Description: Experimental results are presented on the production of light particles (A < 5) and intermediate mass fragments (6 < A < 18) over a large solid angle. The reactions 200 MeV/n Au + Au amd Au + Fe were studied to provide information on multifragmentation processes and collective flow. 20 refs., 6 figs.
Date: May 1, 1987
Creator: Harris, J. W.; Jacak, B. V.; Kampert, K. H.; Claesson, G.; Doss, K. G. R.; Ferguson, R. et al.
Partner: UNT Libraries Government Documents Department
open access

Performance comparisons of low emittance lattices

Description: In this paper, the results of a performance analysis of several low emittance electron storage ring lattices provided by various members of the Lattice Working Group are presented. Altogether, four lattices were investigated. There are two different functions being considered for the low beam emittance rings discussed here. The first is to serve as a Damping Ring (DR), i.e., to provide the emittance damping required for a high energy linear collider. The second is to provide beams for a short w… more
Date: May 1, 1987
Creator: Delahaye, J. P. & Zisman, M. S.
Partner: UNT Libraries Government Documents Department
open access

Alarm points for fixed oxygen monitors

Description: Oxygen concentration monitors were installed in a vault where numerous pipes carried inert cryogens and gases to the Mirror Fusion Test Facility (MFTF-B) experimental vessel at Lawrence Livermore National Laboratory (LLNL). The problems associated with oxygen-monitoring systems and the reasons why such monitors were installed were reviewed. As a result of this review, the MFTF-B monitors were set to sound an evacuation alarm when the oxygen concentration fell below 18%. We chose the 18% alarm c… more
Date: May 1, 1987
Creator: Miller, G.C.
Partner: UNT Libraries Government Documents Department
open access

Gaining control over rare earth valence fluctuations

Description: This paper briefly deals with the problem of narrow band materials. It addresses a new theoretical approach to the fluctuation of valence electrons in rare earth elements. It is believed that the phenomena of interest arize from an instability of the partially filled d or f shell of certain atoms when they are put into a metallic host. The theoretical models which dominate the scene work with two local d or f states on one hand and a structureless sea of free conduction electrons on the other. … more
Date: May 31, 1987
Creator: Wohlleben, D.
Partner: UNT Libraries Government Documents Department
open access

NULLJOB product

Description: The ever increasing demand for more CPU cycles for data analysis on our Central VAX Cluster led us to investigate new ways to utilize more fully the resources that were available. A review of the experiment and software development VAX systems on site revealed many unused computing cycles. Furthermore, these systems were all connected by DECnet which would allow easy file transfer and remote batch job submission. A product was developed to allow jobs to be submitted on the Central VAX Cluster b… more
Date: May 1, 1987
Creator: Hughart, N. & Ritchie, D.
Partner: UNT Libraries Government Documents Department
open access

Searching for 4th generation fermions at high-energy e/sup +/e/sup -/ machines

Description: This writeup summarizes Monte Carlo studies on the feasibility of searching for 4th family fermions at high energy e/sup +/e/sup -/ machines. By high energy it is meant at energies beyond the Z/sup 0/; the Z/sup 0/ searches having been studied extensively by the SLC and LEP collaborations. The specific examples of ..sqrt..s = 200 GeV (namely LEP200) and ..sqrt..s = 600 GeV (in line with work being done at SLAC to investigate the potential of a future linear collider) were chosen. The studies ha… more
Date: May 1, 1987
Creator: Dorfan, J. & Van Kooten, R.J.
Partner: UNT Libraries Government Documents Department
open access

Challenges of nuclear fusion

Description: After 30 years of research and development in many countries, the magnetic confinement fusion experiments finally seem to be getting close to the original first goal: the point of ''scientific break-even.'' Plans are being made for a generation of experiments and tests with actual controlled thermonuclear fusion conditions. Therefore, engineers and material scientists are hard at work to develop the required technology. In this paper the principal elements of a generic fusion reactor are descri… more
Date: May 1, 1987
Creator: Kunkel, W.B.
Partner: UNT Libraries Government Documents Department
open access

The maximum likelihood estimator method of image reconstruction: Its fundamental characteristics and their origin

Description: We review our recent work characterizing the image reconstruction properties of the MLE algorithm. We studied its convergence properties and confirmed the onset of image deterioration, which is a function of the number of counts in the source. By modulating the weight given to projection tubes with high numbers of counts with respect to those with low numbers of counts in the reconstruction process, we have confirmed that image deterioration is due to an attempt by the algorithm to match projec… more
Date: May 1, 1987
Creator: Llacer, J. & Veklerov, E.
Partner: UNT Libraries Government Documents Department
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