Recent 2{omega} gasbag experiments on the Helen laser studied single-beam propagation and backscatter as a function of gas density. We present a comprehensive analysis of these experiments using simulations in HYDRA. Post-processed results agree well with experimental fast x-ray images (FXI) showing stable laser propagation across the bag. The measured total stimulated Raman backscatter (SRS) increases with initial gas density up to n{sub e} {approx} 0.08 n{sub c}, then decreases. Near-backscatter images (NBI) show that the decrease in total SRS with increasing density is not due to scatter outside of the collection optics. SRS gain spectra calculated from the HYDRA results agree well with experimental streak spectra. The tilt and spread in wavelength of the spectra appear to be explained by gasbag hydrodynamics only, with no need to invoke filamentation. Axial density gradients and laser pump absorption may combine to detune and limit SRS gain at high density.

We are developing an all fiber front end for the next generation high-energy petawatt (HEPW) laser at Lawrence Livermore National Laboratory (LLNL). The ultimate goal of the LLNL HEPW effort is to generate 5-kJ pulses capable of compression to 5ps at 1053nm, enabling advanced x-ray backlighters and possible demonstration of fast ignition. We discuss the front-end of the laser design from the fiber master oscillator, which generates the mode-locked 20nm bandwidth initial pulses through the 10mJ output of the large flattened mode (LFM) fiber amplifier. Development of an all fiber front end requires technological breakthroughs in the key areas of the master oscillator and fiber amplification. Chirped pulse amplification in optical fibers has been demonstrated to 1mJ. Further increase is limited by the onset of stimulated Raman scattering (SRS). We have recently demonstrated a new flattened mode fiber technology, which reduces peak power for a given energy and thus the onset of SRS. Controlled experiments with 1st generation fibers yielded 0.5mJ of energy while significantly increasing the point at which nonlinear optical effects degrade the amplified pulse. In this paper we will discuss our efforts to extend this work to greater than 20mJ using our large flattened mode fiber amplifier.

The Advanced Light Source (ALS) saw first light on October 5, 1993, not quite to the day but close to 10 years before the 2003 ALS Users Association meeting, held October 6-8. Fittingly, the proceedings included retrospectives from two of the key players in the early history of the ALS, David Attwood and Jay Marx, and a display of photographs chronicling its construction and commissioning. Science highlights, highlights from young researchers, and posters constituted the meat of the program on Monday and Tuesday morning, while workshops took over Tuesday afternoon and all day Wednesday.

A randomized complete block experiment was performed to measure the effect of prescribed, dormant-season burns of three different levels of severity (measured as fuel consumption and soil surface heating) on subsequent insect infestation and mortality of mature longleaf pine (Pinus palustris Mill.). Multiple-funnel traps baited with a low release rate of turpentine and ethanol were used to monitor activity of certain coniferophagous beetles. Non-aggressive species, including the root beetles Hylastes salebrosus Eichhoff and H. tenuis Eichhoff, the ambrosia beetle Xyleborus pubescens Zimmermann, the reproduction weevil Pachylobius picivorus (Germar), and buprestid borers, were attracted to burned plots in numbers that correlated positively with burn severity. Beetle attraction to burned sites was greatest in the first weeks post-burn and disappeared by the second year. Two potential tree-killing bark beetles, Dendroctonus terebrans (Olivier) and Ips grandicollis (Eichhoff), were trapped in significant numbers but exhibited no attraction to burned plots. Tree mortality correlated significantly with the severity of the burns and amounted to 5% of stems in the hottest burn treatment after 3 years. The majority of the mortality was observed in the second and third years post-burn. Attacks of Ips and Dendroctonus bark beetles were apparent on nearly all dead or dying trees, …

LiCoO{sub 2} is the most common lithium storage material used as positive electrode in lithium rechargeable batteries. Ordering of lithium and vacancies has a profound effect on the physical properties of Li{sub x}CoO{sub 2} and the electrochemical performances of lithium batteries. An exit surface wave (ESW) phase image reconstructed from experimental images obtained on the LBNL One-Angstrom Microscope (OAM) shows all three types of atoms in LiCoO{sub 2}.

The Collider Detector at Fermilab (CDF) records proton-antiproton collisions at center of mass energy of 2.0 TeV at the Tevatron collider. A new collider run, Run II, of the Tevatron started in April 2001. Increased luminosity will result in about 1 PB of data recorded on tapes in the next two years. Currently the CDF experiment has about 260 TB of data stored on tapes. This amount includes raw and reconstructed data and their derivatives. The data storage and retrieval are managed by the CDF Data Handling (DH) system. This system has been designed to accommodate the increased demands of the Run II environment and has proven robust and reliable in providing reliable flow of data from the detector to the end user. This paper gives an overview of the CDF Run II Data Handling system which has evolved significantly over the course of this year. An outline of the future direction of the system is given.

Adaptive optics (AO), a mature technology developed for astronomy to compensate for the effects of atmospheric turbulence, can also be used to correct the aberrations of the eye. The classic phoropter is used by ophthalmologists and optometrists to estimate and correct the lower-order aberrations of the eye, defocus and astigmatism, in order to derive a vision correction prescription for their patients. An adaptive optics phoropter measures and corrects the aberrations in the human eye using adaptive optics techniques, which are capable of dealing with both the standard low-order aberrations and higher-order aberrations, including coma and spherical aberration. High-order aberrations have been shown to degrade visual performance for clinical subjects in initial investigations. An adaptive optics phoropter has been designed and constructed based on a Shack-Hartmann sensor to measure the aberrations of the eye, and a liquid crystal spatial light modulator to compensate for them. This system should produce near diffraction-limited optical image quality at the retina, which will enable investigation of the psychophysical limits of human vision. This paper describes the characterization and operation of the AO phoropter with results from human subject testing.

None

I review investigations of the quark confinement mechanism that have been carried out in the framework of SU(N) lattice gauge theory. The special role of Z(N) center symmetry is emphasized.

A cross-platform component for EPICS Simple Channel Access (SCA) has been developed. EPICS client programs with GUI become portable at their C++ source-code level both on Windows and Linux by using Borland C++ Builder 6 and Kylix 3 on these platforms respectively.

In this paper we discuss recent work on the development of high damage threshold, high efficiency MLD (multilayer dielectric) diffraction gratings for use in high energy, petawatt laser systems. This effort involves a close integration between modeling, fabrication, and testing. The modeling work is used to identify grating designs that satisfy the constraints of high efficiency (>94%) and low field enhancement which is a necessary condition for high damage threshold. Subscale MLD gratings for test are being fabricated in an advanced ion-etch machine we have recently built. The testing effort is being conducted in a dedicated laboratory. The laser beam used to test the samples is based on an OPCPA (optical parametric chirped-pulse amplifier) and a compressor that can provide pulse energies up to 50mJ with pulse lengths variable from 0.3-20 ps. This test station is equipped with diagnostics to fully characterize both the spatial and temporal characteristics of the test beam at the plane of the sample. Initial results have demonstrated a dependence of damage threshold on incident angle that is in good agreement with the field enhancement calculations. We have demonstrated a grating design with a damage threshold of 3J/cm{sup 2} and are investigating manufacturability and reproducibility issues …

At the U. S. Department of Energy Savannah River Site, disposal of radioactive wastes in shallow trenches was simulated with vadose zone models and decoupled aquifer models. The vadose zone models provided contaminant fluxes to the aquifer models.

Based on a review of airflow design factors and in-situ energy measurements in ISO Cleanliness Class-5 cleanrooms, this paper addresses the importance of energy efficiency in airflow design and opportunities of cost savings in cleanroom practices. The paper discusses design factors that can long lastingly affect cleanroom system performance, and demonstrates benefits of energy efficient cleanroom design from viewpoints of environmental control and business operations. The paper suggests that a high performance cleanroom should not only be effective in contamination control, but also be efficient in energy and environmental performance. The paper also suggests that energy efficient design practice stands to bring in immediate capital cost savings and operation cost savings, and should be regarded by management as a strategy to improve business bottom lines.

Zincblende half-metallic compounds such as CrAs, with large magnetic moments and high Curie temperatures, are promising materials for spintronic applications. They explore layered materials, consisting of alternating layers of zincblende half-metals, by first principles calculations, and find that superlattices of (CrAs){sub 1}(MnAs){sub 1} and (CrAs){sub 2}(MnAs){sub 2} are half-metallic with magnetic moments of 7.0{mu}{sub B} and 14.0{mu}{sub B} per unit cell, respectively. They discuss the nature of the bonding and half-metallicity in these materials and, based on the understanding acquired, develop a simple expression for the magnetic moment in such materials. They explore the range of lattice constants over which half-metallicity is manifested, and suggest corresponding substrates for growth in thin film form.

We report on the evolution of defects in Pu during isochronal annealing and self irradiation using positron annihilation spectroscopy. Positron annihilation spectroscopy is a sensitive probe (part per million level) for atomic-scale defects. The spectroscopic tools available at LLNL allow the determination of size, concentration, and chemical surroundings of defects in aged Pu samples. Positron lifetime analysis was performed on eight samples aged 7 months to 42 years. All samples except the 7-month old sample contained a high concentration of positron trapping centers. The dominant component yielded a lifetime value of {approx}182 ps. In aged samples, a second longer lifetime component was observed that appears to increase in strength with the age of the sample. The observed lifetime values and their relative strengths are shown in figure 1. The top panel corresponds to the lifetime values and the bottom panel corresponds to the intensity of the long lifetime component. Positron lifetime values are determined by the bubble size and He content. When He is added to a bubble, the positron lifetime is shortened due to the increased electron density. When the size of the bubble is known from an independent measurement, the observed positron lifetime values and the associated first …

Information management in natural resources has become an overwhelming task. A massive amount of electronic documents and data is now available for creating informed decisions. The problem is finding the relevant information to support the decision-making process. Determining gaps in knowledge in order to propose new studies or to determine which proposals to fund for maximum potential is a time-consuming and difficult task. Additionally, available data stores are increasing in complexity; they now may include not only text and numerical data, but also images, sounds, and video recordings. Information visualization specialists at Pacific Northwest National Laboratory (PNNL) have software tools for exploring electronic data stores and for discovering and exploiting relationships within data sets. These provide capabilities for unstructured text explorations, the use of data signatures (a compact format for the essence of a set of scientific data) for visualization (Wong et al 2000), visualizations for multiple query results (Havre et al. 2001), and others (http://www.pnl.gov/infoviz ). We will focus on IN-SPIRE, a MS Windows vision of PNNL’s SPIRE (Spatial Paradigm for Information Retrieval and Exploration). IN-SPIRE was developed to assist information analysts find and discover information in huge masses of text documents.

A hardware hash sorter for the Fermilab BTeV Level 1 trigger system will be presented. The has sorter examines track-segment data before the data are sent to a system comprised of 2500 Level 1 processors, and rearranges the data into bins based on the slope of track segments. They have found that by using the rearranged data, processing time is significantly reduced allowing the total number of processors required for the Level 1 trigger system to be reduced. The hash sorter can be implemented in an FPGA that is already included as part of the design of the trigger system. Hash sorting has potential applications in a broad area in trigger and DAQ systems. It is a simple O(n) process and is suitable for FPGA implementation. Several implementation strategies will also be discussed in this document.

This paper is a review of heavy quarks in lattice gauge theory, focusing on methodology. It includes a status report on some of the calculations that are relevant to heavy-quark spectroscopy and to flavor physics.

We have designed and built a six-band multi-spectral NIR imaging system used in clinical testing on cancer patients. From our layered tissue model, we create blood volume and blood oxygenation images for patient treatment monitoring.

Superovulation of female mice with exogenous gonadotrophins is routinely used for increasing the number of eggs ovulated by each female in reproductive and developmental studies. We report an unusual effect of superovulation on fertilization in mice. In vivo matings of superovulated T-stock females with B6C3F1 males resulted in a 2-fold reduction (P<0.001) in the frequencies of fertilized eggs compared to control B6C3F1 matings. In addition, {approx}22 hr after mating only 15% of fertilized eggs recovered in T-stock females had reached the metaphase stage of the first cleavage division versus 87% in B6C3F1 females (P < 0.0001). Matings with T-stock males did not improve the reproductive performance of T-stock females. To investigate the possible cause(s) for the impaired fertilization and zygotic development, the experiments were repeated using in vitro fertilization. Under these conditions, the frequencies of fertilized eggs were not different in superovulated T-stock and B6C3F1 females (51.7% {+-} 6.0 and 64.5% {+-}3.8, P=0.10). There was a 7-fold increase in the frequencies of fertilized T-stock eggs that completed the first cell cycle of development after in vitro versus in vivo fertilization. These results rule out an intrinsic deficiency of the T-stock oocyte as the main reason for the impaired fertility after …

Contrary to the behavior of swelling of f.c.c. Fe-15Cr-16Ni and Fe-15Cr-16Ni-0.25Ti alloys irradiated together in the same FFTF-MOTA experiment, Fe-15Cr-16Ti-0.25Ti-0.05C does not exhibit a dependence of swelling on dpa rate at {approx}400 C. The transient regime of swelling is prolonged by carbon addition, however. Addition of boron to the carbon-doped alloy decreases the swelling somewhat but does not restore the sensitivity to dpa rate. It appears that the primary influence of boron is chemical in nature, probably associated with boron's impact on the behavior of carbon. Boron's role as a source of helium is thought to be secondary.

The past several years have seen designs for PET cameras optimized to image the breast, commonly known as Positron Emission Mammography or PEM cameras. The guiding principal behind PEM instrumentation is that a camera whose field of view is restricted to a single breast has higher performance and lower cost than a conventional PET camera. The most common geometry is a pair of parallel planes of detector modules, although geometries that encircle the breast have also been proposed. The ability of the detector modules to measure the depth of interaction (DOI) is also a relevant feature. This paper finds that while both the additional solid angle coverage afforded by encircling the breast and the decreased blurring afforded by the DOI measurement improve performance, the ability to measure DOI is more important than the ability to encircle the breast.

International benchmarking and conference on women in physics.

These lectures are intended to provide an introduction to heavy meson decays and CP violation. The first lecture contains a brief review of the standard model and how the CKM matrix and CP violation arise, mixing and CP violation in neutral meson systems, and explanation of the cleanliness of the sin 2{beta} measurement. The second lecture deals with the heavy quark limit, some applications of heavy quark symmetry and the operator product expansion for exclusive and inclusive semileptonic B decays. The third lecture concerns with theoretically clean CP violation measurements that may become possible in the future, and some developments toward a better understanding of nonleptonic B decays. The conclusions include a subjective best buy list for the near future.