The performance of parallel Monte Carlo transport calculations which use both spatial and particle parallelism is increased by dynamically assigning processors to the most worked domains. Since the particle work load varies over the course of the simulation, this algorithm determines each cycle if dynamic load balancing would speed up the calculation. If load balancing is required, a small number of particle communications are initiated in order to achieve load balance. This method has decreased the parallel run time by more than a factor of three for certain criticality calculations.

We built a bi-directional scatter diagnostics to measure and quantify losses due to scattering and absorption of harmonic conversion crystals (DKDP) for the National Ignition Facility (NIF). The main issues to be addressed are (1) amount of total energy reaching the target if the target hole was {+-}200 {micro}rad in size, (2) distribution of energy inside the target hole, (3) collateral damage of other optics by scattered light. The scatter diagnostics enables angle-resolved measurements at 351 nm, and is capable of both near specular transmission and large angle scatter measurements. In the near specular setup, the transmission can be measured within {+-}65 {micro}rad up to {+-}60 mrad acceptance angle. A silicon photo detector and a scientific-grade CCD camera provide total energy and energy distribution. A linear swing arm detection system enables large angle scatter measurements of 360{sup o}, in principal, with step sizes as small as 0.01{sup o} and different collection angle ranging between 1 and 20 mad. In this paper, scatter effects from laser damage and final finishing process of DKDP are discussed.

The RuC molecule has been a challenging species due to the open-shell nature of Ru resulting in a large number of low-lying electronic states. We have carried out state-of-the-art calculations using the complete active space multi-configuration self-consistent field (CASSCF) followed by multireference configuration interaction (MRCI) methods that included up 18 million configurations, in conjunction with relativistic effects. We have computed 29 low-lying electronic states of RuC with different spin multiplicities and spatial symmetries with energy separations less than 38 000 cm{sup -1}. We find two very closely low-lying electronic states for RuC, viz., {sup 1}{Sigma}{sup +} and {sup 3}{Delta} with the {sup 1}{Sigma}{sup +} being stabilized at higher levels of theory. Our computed spectroscopic constants and dipole moments are in good agreement with experiment although we have reported more electronic states than those that have been observed experimentally. Our computations reveal a strongly bound X{sup 1}{Sigma}{sup +} state with a large dipole moment and an energetically close {sup 3}{Delta} state with a smaller dipole moment. Overall our computed spectroscopic constants of the excited states with energy separations less than 18000 cm{sup -1} agree quite well with those of the corresponding observed states.

We present a study, based on simulations with SERDYCA, a spatially-explicit individual based model of rodent dynamics, on the connection between population persistence and the presence of inhomogeneities in the habitat. We are specifically interested on the effect that inhomogeneities that do not fragment the environment, have on population persistence. Our results suggest that a certain percentage of inhomogeneities can increase the average time to extinction of the population. Inhomogeneities decrease the population density and can increase the ratio of juveniles in the population thus providing a better chance for the population to restore itself after a severe period with critically low population density. We call this the ''inhomogeneity localization effect''.

We consider the full multinomial combinatorics of all irreducible representations of the octahedral (cubic) symmetry as a function of partitions for vertex, face and edge colorings. Full combinatorial tables for all irreducible representations and all multinomial partitions are constructed. These enumerations constitute multinomial expansions of character-based cycle index polynomials, and grow in combinatorial complexity as a function of edge or vertex coloring partitions.

The warm density matter regime of high energy density physics [1, 2, 3] has a high scientific discovery potential for the properties of plasmas at high densities and pressures and at moderate temperatures (kT) in which the Coulomb interaction energy between plasma particles exceed kT. This leads to correlations in the plasma characterized by the dimensionless ''coupling'' parameter {Lambda} > 1, where {Lambda} is defined by {Lambda} = q{sup 2}n{sup 1/3}/kT. Here q is the effective ion charge and n the ion density. Strongly-coupled plasmas with {Lambda} > 1 are difficult to study analytically and by numerical simulation. Many astrophysical systems (e.g., brown dwarfs, and giant planets) and inertial fusion plasmas in the beginning stages of compression fall into this regime. There is an opportunity to develop improved understanding and models through accurate measurements of properties in the large parameter space of temperature and density where data is currently limited or non-existent. X-ray free-electron lasers (Fourth generation light sources), ultra-short pulse and high energy optical lasers, pulsed-power z-pinch x-ray sources, and high explosives are all capable of producing warm dense matter conditions at various temperatures, pressures, and sample sizes. Therefore, the challenge is not how to create warm dense matter …

We investigated chemical etching as a possible means to mitigate the growth of UV laser-induced surface damage on fused silica. The intent of this work is to examine the growth behavior of existing damage sites that have been processed to remove the UV absorbing, thermo-chemically modified material within the affected area. The study involved chemical etching of laser-induced surface damage sites on fused silica substrates, characterizing the etched sites using scanning electron microscopy (SEM) and laser fluorescence, and testing the growth behavior of the etched sites upon illumination with multiple pulses of 351nm laser light. The results show that damage sites that have been etched to depths greater than about 9 {micro}m have about a 40% chance for zero growth with 1000 shots at fluences of 6.8-9.4 J/cm{sup 2}. For the etched sites that grow, the growth rates are consistent with those for non-etched sites. There is a weak dependence of the total fluorescence emission with the etch depth of a site, but the total fluorescence intensity from an etched site is not well correlated with the propensity of the site to grow. Deep wet etching shows some promise for mitigating damage growth in fused silica, but fluorescence does not …

A new technique is described for the isochoric heating (i.e., heating at constant volume) of matter to high energy-density plasma states (>10{sup 5} J/g) on a picosecond timescale (10{sup -12} sec). An intense, collimated, ultrashort-pulse beam of protons--generated by a high-intensity laser pulse--is used to isochorically heat a solid density material to a temperature of several eV. The duration of heating is shorter than the timescale for significant hydrodynamic expansion to occur, hence the material is heated to a solid density warm dense plasma state. Using spherically-shaped laser targets a focused proton beam is produced and used to heat a smaller volume to over 20 eV. The technique described of ultrafast proton heating provides a unique method for creating isochorically heated high-energy density plasma states.

The character theory of relativistic double group spinor representations is developed in order to represent the total rovibronic states of non-rigid molecules. It is shown that the double groups can be represented in terms of wreath products and powerful matrix cycle type generators that are used to construct their character tables. It is shown that these tables are of use when spin-orbit coupling is included in the hamiltonian even for molecules containing lighter atoms. Applications to non-rigid molecules such as Tl{sub 2}H{sub 4} /Tl{sub 2}H{sub 4}{sup +} are considered. It is shown that the tunneling splittings and the nuclear spin statistical weights can be obtained for such species using the character tables thus constructed. The spinor double groups of several other molecules such as hexamethyl dilead and heavy weakly bound clusters such as (PoH{sub 2}){sub 4} are also considered.

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The World Wide Web provides a vast resource to genomics researchers in the form of web-based access to distributed data sources--e.g. BLAST sequence homology search interfaces. However, the process for seeking the desired scientific information is still very tedious and frustrating. While there are several known servers on genomic data (e.g., GeneBank, EMBL, NCBI), that are shared and accessed frequently, new data sources are created each day in laboratories all over the world. The sharing of these newly discovered genomics results are hindered by the lack of a common interface or data exchange mechanism. Moreover, the number of autonomous genomics sources and their rate of change out-pace the speed at which they can be manually identified, meaning that the available data is not being utilized to its full potential. An automated system that can find, classify, describe and wrap new sources without tedious and low-level coding of source specific wrappers is needed to assist scientists to access to hundreds of dynamically changing bioinformatics web data sources through a single interface. A correct classification of any kind of Web data source must address both the capability of the source and the conversation/interaction semantics which is inherent in the design of the …

We present the results of a series of experiments studying how visualization software scales to massive data sets. Although several paradigms exist for processing large data, we focus on pure parallelism, the dominant approach for production software. These experiments utilized multiple visualization algorithms and were run on multiple architectures. Two types of experiments were performed. For the first, we examined performance at massive scale: 16,000 or more cores and one trillion or more cells. For the second, we studied weak scaling performance. These experiments were performed on the largest data set sizes published to date in visualization literature, and the findings on scaling characteristics and bottlenecks contribute to understanding of how pure parallelism will perform at high levels of concurrency and with very large data sets.

The rate coefficient for the reaction of the ethynyl radical (C{sub 2}H) with 1-butyne (H-C{triple_bond}C-CH{sub 2}-CH{sub 3}) is measured in a pulsed Laval nozzle apparatus. Ethynyl radicals are formed by laser photolysis of acetylene (C{sub 2}H{sub 2}) at 193 nm and detected via chemiluminescence (C{sub 2}H + O{sub 2} {yields} CH (A{sup 2}{Delta}) + CO{sub 2}). The rate coefficients are measured over the temperature range of 74-295 K. The C{sub 2}H + 1-butyne reaction exhibits no barrier and occurs with rate constants close to the collision limit. The temperature dependent rate coefficients can be fit within experimental uncertainties by the expression k = (2.4 {+-} 0.5) x 10{sup -10} (T/295 K)-(0.04 {+-} 0.03) cm{sup 3} molecule{sup -1}s{sup -1}. Reaction products are detected at room temperature (295 K) and 533 Pa using a Multiplexed Photoionization Mass Spectrometer (MPIMS) coupled to the tunable VUV synchrotron radiation from the Advanced Light Source at the Lawrence Berkeley National Laboratory. Two product channels are identified for this reaction: m/z = 64 (C{sub 5}H{sub 4}) and m/z = 78 (C{sub 6}H{sub 6}) corresponding to the CH{sub 3}- and H-loss channels, respectively. Photoionization efficiency (PIE) curves are used to analyze the isomeric composition of both product channels. …

This research examined the following items/issues: the NSFD methodology, technical achievements and applications, dissemination efforts and research related professional activities. Also a list of unresolved issues were identified that could form the basis for future research in the area of constructing and analyzing NSFD schemes for both ODE's and PDE's.

In prior years a Wisconsin-SLAC collaboration developed polarized photocathodes which were used for the SLAC SLD and fixed target programs. Currently, the R&D program goal is the development of a polarized electron source (PES) which meets the ILC requirements for polarization, charge, lifetime, and pulse structure. There are two parts to this program. One part is the continued improvement of photocathode structures with higher polarization. The second part is the design and development of the laser system used to drive the photocathode. The long pulse train for the ILC introduces new challenges for the PES. More reliable and stable operation of the PES may be achievable if appropriate R&D is carried out for higher voltage operation and for a simpler photocathode load-lock system. The collaboration with SLAC is through the Polarized Photocathode Research Collaboration (PPRC). Senior SLAC personnel include T. Maruyama, J. Clendenin, R. Kirby, and A. Brachmann.

Strength of the apple parts has been noticed to decrease, especially those installed by the new induction heating system since the LEP campaign started. Fig. 1 shows the ultimate tensile strength (UTS), yield strength (YS), and elongation of the installed or installation-simulated apples on various systems. One can clearly see the mean values of UTS and YS of the post-LEP parts decreased by about 8 ksi and 6 ksi respectively from those of the pre-LEP parts. The slight increase in elongation seen in Fig.1 can be understood from the weak inverse relationship between the strength and elongation in metals. Fig.2 shows the weak correlation between the YS and elongation of the parts listed in Fig. 1. Strength data listed in Figure 1 were re-plotted as histograms in Figs. 3 and 4. Figs. 3a and 4a show histograms of all UTS and YS data. Figs. 3b and 4b shows histograms of pre-LEP data and Figs. 3c and 4c of post-LEP data. Data on statistical scatter of tensile strengths have been rarely published by material suppliers. Instead, only the minimum 'guaranteed' strength data are typically presented. An example of strength distribution of aluminum 7075-T6 sheet material, listed in Fig. 5, show that …

Growth and dissolution of Fe and Mn oxide films are key regulators of the fate and transport of heavy metals in the environment, especially during changing seasonal conditions of pH and dissolved oxygen. The Fe and Mn are present at much higher concentrations than the heavy metals, and, when Fe and Mn precipitate as oxide films, heavy metals surface adsorb or co-precipitate and are thus essentially immobilized. Conversely, when the Fe and Mn oxide films dissolve, the heavy metals are released to aqueous solution and are thus mobilized for transport. Therefore, understanding the dynamics and properties of Fe and Mn oxide films and thus on the uptake and release of heavy metals is critically important to any attempt to develop mechanistic, quantitative models of the fate, transport, and bioavailablity of heavy metals. A primary capability developed in our earlier work was the ability to grow manganese oxide (MnO{sub x}) films on rhodochrosite (MnCO{sub 3}) substrate in presence of dissolved oxygen under mild alkaline conditions. The morphology of the films was characterized using contact-mode atomic force microscopy. The initial growth began by heteroepitaxial nucleation. The resulting films had maximum heights of 1.5 to 2 nm as a result of thermodynamic constraints. …

A coordinate system adapted to the invariant structures of chaotic magnetic fields is constructed. The coordinates are based on a set of ghost-surfaces, defined via an action-gradient flow between the minimax and minimizing periodic orbits. The construction of the chaotic coordinates allows an expression describing the temperature gradient across a chaotic magnetic field to be derived. The results are in close agreement with a numerical calculation.

Absolute line emission cross sections are presented for 1 keV/amu charge exchange collisions of multiply charged solar wind ions with H{sub 2}O, H, O, CO{sub 2}, and CO cometary targets. The present calculations are contrasted with available laboratory data. A parameter-free model is used to successfully predict the recently observed x-ray spectra of comet C/LINEAR 1999 S4. We show that the resulting spectrum is extremely sensitive to the time variations of the solar wind composition. Our results suggest that orbiting x-ray satellites may be a viable way to predict the solar wind intensities and composition on the Earth many hours before the ions reach the earth.

The Confederated Salish and Kootenai Tribes (CSKT) and Montana Fish Wildlife and Parks (MFWP) wrote the 'Fisheries Mitigation Plan for Losses Attributable to the Construction and Operation of Hungry Horse Dam' in March 1991 to define the fisheries losses, mitigation alternatives and recommendations to protect, mitigate and enhance resident fish and aquatic habitat affected by Hungry Horse Dam. On November 12, 1991, the Northwest Power Planning Council (NPPC) approved the mitigation plan with minor modifications, called for a detailed implementation plan, and amended measures 903(h)(1) through (7). A long-term mitigation plan was submitted in August 1992, was approved by the Council in 1993, and the first contract for this project was signed on November 11, 1993. The problem this project addresses is the loss of habitat, both in quality and quantity, in the Flathead Lake and River basin resulting from the construction and operation of Hungry Horse Dam. The purpose of the project is to both implement mitigation measures and monitor the biological responses to those measures including those implemented by Project Numbers 9101903 and 9101904. Goals and objectives of the 1994 Fish and Wildlife Program (Section 10.1) addressed by this project are the rebuilding to sustainable levels weak, but …

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This report summarizes the results of a proejct sponsored by DTRA to 1) Assess the readiness of private-sector businesses, building owners, and service providers to restore property and recover operations in the aftermath of a wide-area dispersal of anthrax; and 2) Understand what private property owners and businesses "want and need" from federal, state, and local government to support recovery and restoration from such an incident.

The program InvMass has been developed to perform a general model-independent search for new particles using the ATLAS detector at the Large Hadron Collider (LHC), a proton-proton collider at CERN. The search is performed by examining statistically significant variations from the Standard Model predictions in exclusive event classes classified according to the number of identified objects. The program, called InvMass, finds all relevant particle groups identified with the ATLAS detector and analyzes their production rates, invariant masses and the total transverse momenta. The generic code of InvMass can easily be adapted for any particle types identified with the ATLAS detector. Several benchmark tests are presented.

This report summarizes the study of the tolerance limits on the assembly of the cathode and the Pierce electrode for the DARHT-II diode (2.5 MV, 2 kA case), performed through a series of computer simulations using the PIC code WARP [1]. We have considered sources of beam quality degradation like the errors in axial and transverse positioning, and the size of the radial gap between the cathode and the Pierce electrode (shroud). The figure of merit was chosen to be the RMS beam (edge) emittance at a distance of 1 meter from the cathode, as defined by {var_epsilon}{sub x} = 4 {beta}{gamma} {radical}(<x{sup 2}><x{prime}{sup 2}>-<xx{prime}>{sup 2}) {center_dot}. The analysis shows that to position the cathode at the correct axial and transverse location is more important than the size of the radial gap.