Several contemporary proton-recoil detectors are described and compared. These detectors have been used for neutron-spectrum measurements over various portions of the 10-keV-to-20-MeV energy range. Several factors which limit the accuracy of the results are compared quantitatively. General suggestions are given for setting and using standard cross sections and for future developments using the n,p scattering reaction.

Progress is reported in the following research areas: cesium fixation in aluminosilicates and supercalcine development; low sodium wastes and high sodium wastes. Phase relations in the appropriate (for supercalcine) portion of the Cs/sub 2/O-Al/sub 2/O/sub 3/-SiO/sub 2/ system are being investigated. Several compatibility lines (tie lines) have been established on the phase diagram. Methods of preparing pure single phases of CsAlSiO/sub 4/ and CsAlSi/sub 2/O/sub 6/ (pollucite) are being developed. Compatibility studies continue to be the basis of supercalcine crystalline phase formation modeling. (LK)

We have conducted tests to ascertain whether or not exposure to erbia would adversely affect the mechanical properties of vanadium more than the regular annealing furnace environment. Mechanical properties of the vanadium exposed to erbia are not different from those of the vanadium to a regular annealing furnace environment. However, there is a change in the impurity levels, the carbon content increasing and the oxygen content decreasing. There is also anomalous behavior in the strain-hardening and elongation to failure of both the annealed and the erbia specimens. It is possible that hydrogen could have been released as a result of water reacting with the vanadium to form oxides. Very small amounts of hydrogen can impair the mechanical properties of vanadium. It is possible, on the basis of diffusion data, that, should hydrogen be generated in this fashion, it could diffuse completely through the vanadium and contaminate whatever is in contact with the vanadium. Further experiments should be conducted to verify whether or not hydrogen is in fact responsible for the anomalous strain-hardening and elongation-to-failure behavior. 20 refs., 8 figs., 3 tabs.

Channeling of positrons in single crystals of silicon was observed in transmission and scattering measurements for incident energies from 16 to 28 MeV. In addition, the spectral dependence upon crystal orientation of the forward coherent bremsstrahlung produced by beams of 28-MeV positrons and electrons incident upon a 5 ..mu..m thick single crystal of silicon was measured with a NaI photon spectrometer. Effects of channeling and perhaps of the nonvalidity of the first Born approximation were observed for beam directions near the (111) axis of the crystal, and coherent peaks near 0.5 MeV were observed for a compound interference direction, in agreement with first-order theoretical calculations. 32 fig.

This report presents the results of measurements of two quadrupole magnets that are used in the 200 MeV transfer line. The measurements were performed to obtain data to evaluate the suitability of these magnets for use in a 400 MeV transfer line once the Linac Upgrade is complete. In order to provide a basis for comparison, data were obtained from Fermilab's Magnet Test Facility of measurements of magnets of similar size and strength that were built for the Loma Linda project. These Loma Linda magnets are possible replacements for the ones presently in the 200 MeV transfer line. The Fermilab Linac Upgrade includes the reconfiguration of the transfer line that runs from the linac to the booster in order to handle the higher beam energy. Nominally, the quadrupole strengths will need to be 1.5 times their current operating points. This report will use a value of 1.7 to allow a tuning range to account differences in geometry between the old and new lines. Another goal in the design of the new transfer line is to produce a non-steering line. A complaint about the current line is that steering results from any attempt to re-tune the line. 18 figs., 3 tabs.

The new heavy ion synchrotron facility proposed by GSI will have two superconducting magnet rings in the same tunnel, with rigidities of 300 T-m and 100 T-m. Fast ramp times are needed, which can cause significant problems for the magnets, particularly in the areas of ac loss and magnetic field distortion. The development of the low loss Rutherford cable that can be used is described, together with a novel insulation scheme designed to promote efficient cooling. Measurements of contact resistance in the cable are presented and the results of these measurements are used to predict the ac losses, in the magnets during fast ramp operation. For the high energy ring, a lm model dipole magnet was built, based on the RHIC dipole design. This magnet was tested under boiling liquid helium in a vertical cryostat. The quench current showed very little dependence on ramp rate. The ac losses, measured by an electrical method, were fitted to straight line plots of loss/cycle versus ramp rate, thereby separating the eddy current and hysteresis components. These results were compared with calculated values, using parameters which had previously been measured on short samples of cable. Reasonably good agreement between theory and experiment was found, …

This paper contains three analytical solutions of transport problems which can be used to test ray-effect errors in the numerical solutions of the Boltzmann Transport Equation (BTE). We derived the first two solutions and the third was shown to us by M. Prasad. Since this paper is intended to be an internal LLNL report, no attempt was made to find the original derivations of the solutions in the literature in order to cite the authors for their work.

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New techniques developed in connection with the NNLO corrections to the Higgs production rate at hadron colliders and some recent applications are reviewed.

Shock-induced twinning and martensitic transformation in BCC-based polycrystalline metals (Ta and U-6wt%Nb) have been observed and studied using transmission electron microscopy (TEM). The length-scale of domain thickness for both twin lamella and martensite phase is found to be smaller than 100 nm. While deformation twinning of {l_brace}112{r_brace}<111>-type is found in Ta when shock-deformed at 15 GPa, both twinning and martensitic transformation are found in Ta when shock-deformed at 45 GPa. Similar phenomena of nanoscale twinning and martensitic transformation are also found in U6Nb shock-deformed at 30 GPa. Since both deformation twinning and martensitic transformation occurred along the {l_brace}211{r_brace}{sub b} planes associated with high resolved shear stresses, it is suggested that both can be regarded as alternative paths for shear transformations to occur in shock-deformed BCC metals. Heterogeneous nucleation mechanisms for shock-induced twinning and martensitic transformation are proposed and discussed.

Initial dislocation structure in annealed high-purity Mo single crystals and deformation substructure in a crystal subjected to 1% compression have been examined and studied in order to investigate dislocation multiplication mechanisms in the early stages of plastic deformation. The initial dislocation density is in a range of 10{sup 6} {approx} 10{sup 7} cm{sup -2}, and the dislocation structure is found to contain many grown-in superjogs along dislocation lines. The dislocation density increases to a range of 10{sup 8} {approx} 10{sup 9} cm{sup -2}, and the average jog height is also found to increase after compressing for a total strain of 1%. It is proposed that the preexisting jogged screw dislocations can act as (multiple) dislocation multiplication sources when deformed under quasi-static conditions. Both the jog height and length of link segment (between jogs) can increase by stress-induced jog coalescence, which takes place via the lateral migration (drift) of superjogs driven by unbalanced line-tension partials acting on link segments of unequal lengths. Applied shear stress begins to push each link segment to precede dislocation multiplication when link length and jog height are greater than critical lengths. This dynamic dislocation multiplication source is subsequently verified by direct simulations of dislocation dynamics under …

To address SNJV concerns that fluoride in Nevada Test site (NTS) groundwaters may impact radionuclide speciation and transport, NTS water quality databases were obtained and scanned for analyses with high fluoride concentrations (> 10 mg/L). The aqueous speciation of nine representative samples of these groundwaters with added trace amounts of uranium (U), neptunium (Np), plutonium (Pu), americium (Am) and europium (Eu) was then calculated with the computer code EQ3NR assuming a temperature of 25 C, using currently available thermodynamic data for these species. Under conditions where U(VI), Np(V), Pu(IV), Am(III) and Eu(III) dominate, F complexes are insignificant (<1 mole %) for U, Np, Pu and Am. Eu-F complexes may be significant in groundwaters that lack bicarbonate, possess pH values less than about 7 at ambient temperatures, or contain F in extremely high concentrations (e.g. > 50 mg/L). The objective is to evaluate the extent to which fluoride in NTS groundwaters complex U(VI), Np(V), Pu(IV), Am(III) and Eu(III). The approach used is to screen existing databases of groundwater chemistry at NTS for waters with high fluoride concentrations and calculate the extent to which fluoride complexes with the nuclides of interest in these waters.

The dataset for this report is described in Walter et al. (2004) and consists primarily of Nevada Test Site (NTS) explosions, hole collapse and earthquakes. In addition, there were several earthquakes in California and Utah; earthquakes recorded near Cataract Creek, Arizona; mine blasts at two areas in Arizona; and two mine collapses in Wyoming. In the vicinity of NTS there were mainshock/aftershock sequences at Little Skull Mt, Scotty's Junction and Hector ere mine. All the events were shallow and distances ranged from about 0.1 degree to regional distances. All of the data for these events were carefully reviewed and analyzed. In the following sections of the report, we describe analysis procedures, problems with the data and results of analysis.

Strained semiconductor thin films grown epitaxially on semiconductor substrates of different composition, such as Si{sub 1-x}Ge{sub x}/Si, are becoming increasingly important in modern microelectronic technologies. In this paper, we report a hierarchical computational approach for analysis of dislocation formation, glide motion, multiplication, and annihilation in Si{sub 1-x}Ge{sub x} epitaxial thin films on Si substrates. Specifically, a condition is developed for determining the critical film thickness with respect to misfit dislocation generation as a function of overall film composition, film compositional grading, and (compliant) substrate thickness. In addition, the kinetics of strain relaxation in the epitaxial film during growth or thermal annealing (including post-implantation annealing) is analyzed using a properly parameterized dislocation mean-field theoretical model, which describes plastic deformation dynamics due to threading dislocation propagation. The theoretical results for Si{sub 1-x}Ge{sub x} epitaxial thin films grown on Si (100) substrates are compared with experimental measurements and are used to discuss film growth and thermal processing protocols toward optimizing the mechanical response of the epitaxial film.

In HGHG FEL the optimum strength of dispersive section is determined by the maximum bunching that beam obtains after interaction with seed laser. In this paper we present a simple semi-analytic expression of the required dispersive section strength for a wide range of laser power, intrinsic energy spread and harmonic number.

Domain decomposed Monte Carlo codes, like other domain-decomposed codes, are difficult to debug. Domain decomposition is prone to error, and interactions between the domain decomposition code and the rest of the algorithm often produces subtle bugs. These bugs are particularly difficult to find in a Monte Carlo algorithm, in which the results have statistical noise. Variations in the results due to statistical noise can mask errors when comparing the results to other simulations or analytic results. If a code can get the same result on one domain as on many, debugging the whole code is easier. This reproducibility property is also desirable when comparing results done on different numbers of processors and domains. We describe how reproducibility, to machine precision, is obtained on different numbers of domains in an Implicit Monte Carlo photonics code.

Time series analysis techniques are applied to wave-front sensor telemetry data from the Lick Adaptive Optics System. For 28 fully-illuminated subapertures, telemetry data of 4096 consecutive slope estimates for each subaperture are available. The primary problem is performance comparison of alternative wave-front sensing algorithms. Using direct comparison of data in open loop and closed-loop trials, we analyze algorithm performance in terms of gain, noise and residual power. We also explore the benefits of multi-input Wiener filtering and analyze the open-loop and closed-loop spatial correlations of the sensor measurements.

Skin detection is an important preliminary process in human motion analysis. It is commonly performed in three steps: transforming the pixel color to a non-RGB colorspace, dropping the illumination component of skin color, and classifying by modeling the skin color distribution. In this paper, we evaluate the effect of these three steps on the skin detection performance. The importance of this study is a new comprehensive colorspace and color modeling testing methodology that would allow for making the best choices for skin detection. Combinations of nine colorspaces, the presence of the absence of the illuminance component, and the two color modeling approaches are compared. The performance is measured by using a receiver operating characteristic (ROC) curve on a large dataset of 805 images with manual ground truth. The results reveal that (1) the absence of the illuminance component decreases performance, (2) skin color modeling has a greater impact than colorspace transformation, and (3) colorspace transformations can improve performance in certain instances. We found that the best performance was obtained by transforming the pixel color to the SCT, HSI, or CIELAB colorspaces, keeping the illuminance component, and modeling the color with the histogram approach.

A very long base line super neutrino beam facility is need to determine the neutrino mixing amplitudes and phase accurately, as well as the CP violation parameters. This is possible due to the long distance and wideband nature of the neutrino beam for the observation of several oscillations from one species of the neutrino to the other. BNL plans to upgrade the AGS proton beam from the current 0.14 MW to higher than 1.0 MW and beyond for such a neutrino facility which consists of three major subsystems. First is a 1.2 GeV superconducting linac to replace the booster as injector for the AGS, second is the performance upgrade for the AGS itself for the higher intensity and repetition rate, and finally is target and horn system for the neutrino production. The major contribution for the higher power is from the increase of the repetition rate of the AGS form 0.3 Hz to 2.5 Hz, with moderate increase from the intensity. The design consideration to achieve high intensity and low losses for the linac and the AGS will be reviewed. The target horn design for high power operation and easy maintenance will also be presented.

Fused silica and Si-O{sub x} coatings are of interest for use under high flux conditions of laser light. Si-O{sub x} coatings are sputter deposited from silicon and fused quartz targets using planar magnetrons operated in the rf mode with a variable working-gas mixture of Argon-Oxygen. A series of coatings are prepared on optically flat, fused quartz substrates. Analysis of surface curvature reveals the deposition process conditions that minimize residual stress. Compressive stress levels that exceed 1.5 GPa can be reduced to less than 0.4 GPa for an optimum working gas pressure. Characterization using Rutherford backscattering and x-ray photoelectron spectroscopy indicates that both the fused quartz and silicon targets can be used to sputter deposit coatings with the chemical bonding features of the fused-quartz substrate material.

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Solid radioactive wastes resulting from chemical separations processing of spent reactor fuels have been disposed by burial in trenches in the 200 Areas since 1944. Solid radioactive wastes from other Hanford facilities and from off-site AEC contractors have also been buried in the 200 Areas` Waste Burial Grounds. Since 1970, industrial wastes containing or suspected of containing transuranic radionuclides have been packaged in concrete boxes and {open_quotes}dry wastes{close_quotes} have been packaged in steel boxes or drums and buried in segregated trenches. A land area of approximately 149 acres has been used to bury 5.2 million cubic feet of contaminated solid waste through calendar year 1971. Annual reports of radioactive solid waste burials issued, beginning in 1968, have shown land area used, and volume and quantity of radioactivity grams U and/or Pu and curies buried. No corrections for radioactive decay have been reported. In July 1972, J. D. Anderson, G. L. Hanson, G. R. Kiel, B. J. McMurray, and N. P. Nisick were assigned the responsibility for a study to provide the decayed inventory of radioactivity in each solid waste burial ground in the 200 Areas. The results of this study are included as Tables 1 and 2 in this report.

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The goal of this contractual effort is the development and demonstration of a Road Transportable Analytical Laboratory (RTAL) system to meet the unique needs of the Department of Energy (DOE) for rapid, accurate analysis of a wide variety of hazardous and radioactive contaminants in soil, groundwater, and surface waters. This laboratory system will be designed to provide the field and laboratory analytical equipment necessary to detect and quantify radionuclides, organics, heavy metals and other inorganics, and explosive materials. The planned laboratory system will consist of a set of individual laboratory modules deployable independently or as an interconnected group to meet each DOE site`s specific needs.