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Optical model calculations of nucleon interactions with /sup 93/Nb, from 10 keV up to 50 MeV. [Spherical potential]

Description: The neutron spherical optical potential is determined following the SPRT method by a fit to strength functions, scattering radius, total cross section and neutron elastic scattering data. Comparison to the potential obtained with existing proton scattering data, (p,p) (p,n), provides a basis for the determination of the complex symmetry term of the optical potential. Calculations using the J.L.M. optical model will be also presented and discussed. 18 references.
Date: January 1, 1979
Creator: Lagrange, C.
Partner: UNT Libraries Government Documents Department

GAMMON activation library

Description: The GAMMON activation library is specifically designed for fusion reaction application, but is also adequate for many other design studies. The library contains multigroup cross sections (in 100 energy groups) for 420 neutron-induced reactions, multigroup gamma-ray spectra (in 25 energy groups) for 107 unique daughter products, maximum permissible concentrations (MPC's) for 200 reaction products, and absorbable decay energy (sensible heat) for 85 products. 3 tables.
Date: September 1, 1979
Creator: Battat, M.E.; LaBauve, R.J. & Muir, D.W.
Partner: UNT Libraries Government Documents Department

Laser-based instrumentation for detection of chemical-warfare agents

Description: Several laser-based techniques are being developed for remote, point, and surface contamination detection of chemical warfare agents. These techniques include optoacoustic spectroscopy, laser-induced breakdown spectroscopy, and synchronous detection of laser-induced fluorescence. Detection limits in the part-per-million to part-per-billion regime have been demonstrated.
Date: January 1, 1981
Creator: Quigley, G. P.; Radziemski, L. J.; Sander, R. K. & Hartford Jr., A.
Partner: UNT Libraries Government Documents Department

Radial pulsation analyses of DA dwarfs

Description: A careful study is made of realistic white dwarf envelopes with new opacities in order to identify any destabilizing mechanisms present in the models with a future application to a nonradial study. The initial results showed that the high order radial overtones were unstable. An extension is now made to various chemical compositions and slightly more realistic radii. This always shows that there is an instability strip lying at a certain temperature range depending upon the composition. The radial eigenfunctions are shown and the growth rates discussed. Also the work function integral is given. The possible mechanism and observational problems for these unstable modes are considered. 17 references. (JFP)
Date: January 1, 1979
Creator: Starrfield, S.; Cox, A.N. & Hodson, S.W.
Partner: UNT Libraries Government Documents Department

NEPS reactor and heat exchanger. Summary status (December 1978)

Description: The design of a 3 MW(+) heat-pipe cooled nuclear reactor for electric propulsion of spacecrafts has been evolving continually. Several modifications have been made to make the reactor design more tolerant of potential heat pipe failures. Design parameters and operating characteristics for the modified reactor are presented. The desirability of separating the reactor assembly from the thermionic converter assembly has been recognized, and an intermediate heat exchanger to couple the two subassemblies together has been conceptualized.
Date: June 1, 1979
Creator: Koenig, D. R.
Partner: UNT Libraries Government Documents Department

Physical conditions in reversed field pinches and theta pinches as inferred from simulations

Description: The nature of the transport in certain pinches is investigated by comparing experimental data with computational predictions of the AURORA code. It is shown that anomalous resistivity and anomalous thermal conduction are present during the implosion phase of the ZT-S reversed field pinch, and that as equilibrium is approached the anomalous contribution to the transport coefficients decrease. Evidence is presented indicating that a low density wall emitted plasma occupies the region between the main plasma column and the wall. Simulations of a theta-pinch show that anomalous heating of the ions due to microturbulent fields makes a noticeable contribution to the ion energetics.
Date: January 1, 1979
Creator: Sgro, A.
Partner: UNT Libraries Government Documents Department

Hydrogeochemical and stream sediment reconnaissance of the National Uranium Resource Evaluation Program primarily for the Rocky Mountain states of New Mexico, Colorado, Wyoming, and Montana, and the State of Alaska. Semiannual progress report, October 1978-March 1979

Description: During this six-month period, Hydrogeochemical and Stream Sediment Reconnaissance samples were collected by the Los Alamos Scientific Laboratory (LASL) from 623 locations in Colorado for a special study. Additional special studies are planned for nine other areas in the Rocky Mountain states in fiscal year 1979, plus some cleanup reconnaissance sampling in parts of four quadrangles that overlap state borders. Preparations for reconnaissance sampling of the entire North Slope region of Alaska have been made but sampling is contingent upon receiving supplemental funds. Water samples from 6725 locations were analyzed for uranium by fluorometry or delayed-neutron counting (DNC). Water samples from 9390 locations were analyzed by emission spectroscopy for 12 other elements. Sediment samples from 14,414 locations were analyzed for uranium and 31 other elements by combined DNC and neutron activation analysis. Sediment samples from 9876 locations were analyzed for two additional elements by x-ray fluorescence. Nine LASL reconnaissance reports, one pilot study data release, one supplemental multielement data release, a multielement data release for three areas in western Alaska, and one quarterly report were open filed by the Department of Energy, Grand Junction Office during the six-month period. Numerous other reports are in various stages of completion and several will be open filed in the near future.
Date: July 1, 1979
Creator: Aamodt, P. L.; Bunker, M. E.; Waterbury, G. R. & Waller, R. A.
Partner: UNT Libraries Government Documents Department

Report on the Los Alamos Kaon Factory seminar: physics

Description: The motivations, discussions, and preliminary conclusions of the LASL Kaon Factory Seminar, which met 15 times in the Spring of 1979, are reported. It is technically feasible, but expensive, to build a kaon factory using LAMPF as an injector. Taking advantage of the increased beam intensity, excellent secondary beam lines could be built. While we continue further study of the physics justification for a kaon factory, we also propose to gradually increase LASL participation in kaon and antiproton physics.
Date: January 1, 1979
Creator: Silbar, R.R.
Partner: UNT Libraries Government Documents Department

Sampling the Fermi-Dirac density

Description: A method is given for sampling the nonrelativistic Fermi-Dirac electron energy density for all values of the degeneracy parameter eta on the range - infinity < eta less than or equal to 50. The efficiency of the various rejection techniques employed is never less than 30%, and drops below 50% only for a short range of eta values around eta = 2. The range can certainly be extended beyond eta = 50, the efficiency there being 71%, and decreasing very slowly. 5 references.
Date: July 1, 1979
Creator: Cashwell, E.D. & Everett, C.J.
Partner: UNT Libraries Government Documents Department

Prototype particulate stack sampler with single-cut nozzle and microcomputer calculating/display system

Description: A prototype particulate stack sampler (PPSS) has been developed to improve on the existing EPA Method 5 sampling apparatus. Its primary features are (1) higher sampling rate (56 1/min); (2) display (on demand) of all required variables and calculated values by a microcomputer-based calculating and display system; (3) continuous stack gas moisture determination; (4) a virtual impactor nozzle with 3 ..mu..m mass median diameter cutpoint which collects fine and coarse particle fractions on separate glass fiber filters; (5) a variable-area inlet to maintain isokinetic sampling conditions; and (6) conversion to stainless steel components from the glass specified by EPA Method 5. The basic sampling techniques of EPA Method 5 have been retained; however, versatility in the form of optional in-stack filters and general modernization of the stack sampler have been provided in the prototype design. Laboratory testing with monodisperse dye aerosols has shown the present variable inlet, virtual impactor nozzle to have a collection efficiency which is less than 77% and significant wall losses. This is primarily due to lack of symmetry in this rectangular jet impactor and short transition lengths dictated by physical design constraints (required passage of the nozzle through a 7.6 cm (3 in) diameter stack port). Electronic components have shown acceptable service in laboratory testing although no field testing of the prototype under a broad range of temperature, humidity, and SO/sub 2/ concentration has been undertaken.
Date: January 1, 1979
Creator: Eler, J.C.; Littlefield, L.G. & Tillery, M.I.
Partner: UNT Libraries Government Documents Department

Losses in a built-up conductor for large pulsed coils

Description: Hysteretic and pulsed-field loss measurements have been performed on cables built up from a basic Nb-Ti composite conductor. Measurements were performed on the basic composite; on first-level cables, consisting of six soft copper wires twisted tightly around the basic composite; and on second-level cables, fabricated by twisting six first-level cables around either a bare or formvar-insulated center copper wire. Results of the measurements were analyzed in terms of a recent theory by Turck for losses in multifilamentary wires. We found from this analysis that contact resistances between constituent conductors in both first- and second-level cables play an important role in determining the pulsed-field loss values. We have been able to vary the degree of interstrand resistive coupling by compacting the cables and by solder-filling them. When the contact is good, as for solder-filled cables, the losses increase by about a factor of 7.5 for long pulse times relative to non-solder-filled, non-compacted cables. For relatively high contact resistances, as for unsoldered cables, the constituent conductors are more nearly decoupled from each other and the losses are low. From the study we have found that it is possible to produce, in a simple manner, fully-stabilized, high-current cables that exhibit low pulsed-field losses. Such conductors are attractive for application in Tokomak induction heating and energy storage magnets.
Date: January 1, 1979
Creator: Thompson, J. D.; Wollan, J. J.; Turck, B. & Schermer, R. I.
Partner: UNT Libraries Government Documents Department

ENDF/B-IV, and V cross section libraries for thermal power reactor analysis

Description: The NJOY processing system was used to produce thermal reactor cross-section libraries from ENDF/B-IV, and -V evaluations for the fuel cycle codes EPRI-CELL and EPRI-CPM, for the continuous-energy Monte Carlo code MCNP, and for the Los Alamos discrete-ordinates transport codes. This consistent data source allowed the approximate methods (equivalence theory, B/sub 1/, integral transport, P/sub L/-S/sub N/) to be compared with accurate Monte Carlo results. So far, this has resulted in improved methods for space-and-energy self-shielding in the resonance range (e.g., the NJOY flux calculator, epithermal disadvantage factors for EPRI-CELL, shielded elastic removal), it has shown why the newest ENDF-based libraries initially gave results worse than the old libraries, and it has pointed out problems for future study such as resonance interference effects at high burnup. Finally, the results are compared to various criticality benchmarks to evaluate the performance of ENDF/B-V for thermal reactor analysis and to establish the biases introduced by the approximate methods used in the fuel cycle codes. 3 tables.
Date: January 1, 1979
Creator: MacFarlane, R.E.
Partner: UNT Libraries Government Documents Department

Solar heating and cooling working fluids released to the ecosystem

Description: Gylcols, polygloycols, silicone oils, hydrocarbon oils and various corrosion inhibitors and biocides used in solar heating and cooling systems are tested and evaluated for their potential effects on soils, vegetation, and in regard to potential groundwater contamination. Experimental tests include measurement of the effects of additions of these substances to soils on soil microbial respiration, above ground vegetation, and on the mobilization of chemicals in soil water, including the test substance and any significant biodegradation products. Experimental work aims at developing the data base necessary to evaluate the environmental acceptability of the wide range of materials used for this purpose, addressing the need for development of disposal practices and the means of mitigating effects on the environment due to accidental releases.
Date: January 1, 1978
Creator: Wilson, D.W. & Miera, F.R. Jr.
Partner: UNT Libraries Government Documents Department

Aplanatic waxicons

Description: Waxicon mirror components offer many advantages in designing optical systems for transporting high power laser beams. The widespread use of waxicons has been limited because of their high sensitivity to tilt errors. This paper gives the equations of the surfaces of a waxicon that is rigorously corrected for both spherical aberration and coma. Computer ray tracing has confirmed its low sensitivity to tilt errors: if the aplantic waxicon as a whole is tilted by a small angle delta, the RMS wavefront error in the output beam will be proportional to delta/sup 2/.
Date: January 1, 1979
Creator: Minerbo, G.N.
Partner: UNT Libraries Government Documents Department

Specific heat and thermal conductivity of explosives, mixtures, and plastic-bonded explosives determined experimentally

Description: The specific heat and thermal conductivity of explosives and plastic-bonded explosives of interest to WX operations, determined experimentally, are reported in three tables. Specific heat was determined by differential scanning calorimetry against sapphire standards. Thermal conductivity was determined by two means: the guarded hot-plate method or the differential scanning calorimeter comparative method on miniature samples.
Date: September 1, 1979
Creator: Baytos, J.F.
Partner: UNT Libraries Government Documents Department

Modular design aspects of the FMIT drift-tube linac

Description: The Fusion Materials Irradiation Test (FMIT) Facility drift-tube linac may be subject to high levels of activation because of distributed spill of the deuteron beam. The drift-tube suspension system will use a modular design to allow repairs and alignment to be made without manned entry into the tanks. Design details are presented that show the resulting high degree of flexibility. Because the accelerator will be installed at the Hanford Engineering Development Laboratory (HEDL) at Richland, Washington, it is desirable that large prefabricated tank assemblies (15 m and 18 m long by 2.5 m diameter) be delivered to the construction site. Stress studies and vacuum sealing tests have influenced the design and these results are given. The rf power dissipation in the tank walls is 1.5 MW and requires a high-capacity cooling system. Finally, rf tuning of the tanks is complicated by the presence of girder slots and open vacuum ports.
Date: January 1, 1979
Creator: Liska, D.J.; Schamaun, R.G. & Fox, W.
Partner: UNT Libraries Government Documents Department

Numerical treatment of linearized equations describing inhomogeneous collisionless plasmas

Description: The equations governing the small-signal response of spatially inhomogeneous collisionless plasmas have practical significance in physics, for example in controlled thermonuclear fusion research. Although the solutions are very complicated and the equations are different to solve numerically, effective methods for them are being developed which are applicable when the equilibrium involves only one nonignorable coordinate. The general theoretical framework probably will provide a basis for progress when there are two or three nonignorable coordinates.
Date: January 1, 1979
Creator: Lewis, H.R.
Partner: UNT Libraries Government Documents Department

Petrology of the Apollo 12 Pigeonite Basalt Suite

Description: A comparative petrologic study of the Apollo 12 pigeonite basalt suite has been undertaken to answer the following questions: (1) What are the textural and petrologic variations within the pigeonite suite. (2) Are these variations consistent with the hypothesis that the pigeonite basalts are related by crystal fractionation to the olivine basalts. Texturally, the pigeonite basalts range from porphyritic samples with a very fine-grained variolitic groundmass to coarse-grained microgabbro samples with ophitic to graphic textures. The abundances of olivine and Cr-spinel continuously decrease with increasing grain size, whereas the abundances of plagioclase and ilmenite steadily increase. Petrologically, increasing grain size is accompanied by increased Ca in plagioclase, increased Fe in pyroxene, olivine, and spinel, and less Al, Ti, and Cr in pyroxene. All of these changes, including the differences in bulk chemistry can be explained by near-surface fractionation of olivine, pigeonite, and Cr-spinel with the compositions of the observed phenocryst phases.
Date: January 1, 1979
Creator: Baldridge, W. S.; Beaty, D. W.; Hill, S. M. R. & Albee, A. L.
Partner: UNT Libraries Government Documents Department

Development of Helios target insertion mechanism

Description: A system for precisely positioning a DT-filled target in the Helios target vacuum chamber is described. The target insertion mechanism (TIM), which is designed to insert either a target or a surrogate sphere into the vacuum chamber through an airlock to prevent loss of vacuum, is discussed in detail and its performance is evaluated.
Date: January 1, 1979
Creator: Day, R. D.; Cummings, C. E. & Tucker, H. E.
Partner: UNT Libraries Government Documents Department

Single particle analysis with a 360/sup 0/ light scattering photometer

Description: Light scattering by single spherical homogeneous particles in the diameter range 1 to 20 ..mu..m and relative refractive index 1.20 is measured. Particle size of narrowly dispersed populations is determined and a multi-modal dispersion of five components is completely analyzed. A 360/sup 0/ light scattering photometer for analysis of single particles has been designed and developed. A fluid stream containing single particles intersects a focused laser beam at the primary focal point of an ellipsoidal reflector ring. The light scattered at angles theta = 2.5/sup 0/ to 177.5/sup 0/ at phi = 0/sup 0/ and 180/sup 0/ is reflected onto a circular array of photodiodes. The ellipsoidal reflector is situated in a chamber filled with fluid matching that of the stream to minimize refracting and reflecting interfaces. The detector array consists of 60 photodiodes each subtending 3/sup 0/ in scattering angle on 6/sup 0/ centers around 360/sup 0/. 32 measurements on individual particles can be acquired at rates of 500 particles per second. The intensity and angular distribution of light scattered by spherical particles are indicative of size and relative refractive index. Calculations, using Lorenz--Mie theory, of differential scattering patterns integrated over angle corresponding to the detector geometry determined the instrument response to particle size. From this the expected resolution and experimental procedures are determined.Ultimately, the photometer will be utilized for identification and discrimination of biological cells based on the sensitivity of light scattering to size, shape, refractive index differences, internal granularity, and other internal morphology. This study has demonstrated the utility of the photometer and indicates potential for application to light scattering studies of biological cells.
Date: June 1, 1979
Creator: Bartholdi, M.F.
Partner: UNT Libraries Government Documents Department

Investigation of efficiency optimization in free electron lasers

Description: The dynamics of trapped particles in the presence of the wiggler magnetic field and the electromagnetic radiation field in free electron lasers were investigated. From the results of computer simulations, it was found that, for a given set of parameters, the efficiency of energy extraction from the electron beam maximizes at a particular intensity of the electromagnetic radiation. Based on the physical argument of the dynamics of the trapped particles, a criterion which predicts accurately the optimum intensity of the electromagnetic radiation was obtained. (TFD)
Date: January 1, 1979
Creator: Kwan, T. J. T.
Partner: UNT Libraries Government Documents Department

In-plant evaluation of a uranium NDA system

Description: A uranium solution assay system was developed to allow accurate, timely process control, accountability, and criticality data to be obtained. In it, Ge(Li) ..gamma..-ray spectroscopy is integrated with an interactive computer software package. The U concentation range is divided into three material categories: raffinates and distillates, leach solutions, and concentrated leach solutions. (DLC)
Date: January 1, 1979
Creator: Baxman, H. R.; Langner, D. G.; Sprinkle, J. K.; Sampson, T. E. & Canada, T. R.
Partner: UNT Libraries Government Documents Department

LAMPF neutrino experiment to test muon number conservation

Description: The need for a muon number conservation law separate from lepton number conservation is mandated by the absence of neutrinoless muon-electron transitions. The form of the muon number conservation law, however, is not determined by these considerations. A search was made for electron antineutrinos coming from positive muon decays, which would be allowed by a multiplicative formulation of muon number conservation, but not by an additive formulation. The LAMPF beam dump was used as a source of positive muons decaying at rest; electron antineutrinos were detected via inverse beta decay in a six-ton water Cerenkov counter. No excess of events above known backgrounds was seen; a limit was placed on the branching ratio for positive muon decay to electron antineutrinos of R < 6.5%. Electron neutrinos from normal muon decay were detected during a fill of the counter with heavy water, via the inverse beta decay on the deuteron. The cross section for this reaction was measured, averaged over the neutrino energy spectrum; the measured value of (0.52 +- 0.18) x 10/sup -40/ cm/sup 2/ is in good agreement with the calculated value of 0.48 x 10/sup -40/ cm/sup 2/.
Date: September 1, 1979
Creator: Willis, S.E.
Partner: UNT Libraries Government Documents Department
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