Photocathode rf guns depend on mode locked laser systems to produce an electron beam at a given phase of the rf. In general, the laser pulse is less than {sigma}{sub z} = 10{sup o} of rf phase in length and the required stability is on the order of {Delta}{phi} = 1{sup o}. At 90 GHz (W-band), these requirements correspond to {sigma}{sub z} = 333 fsec and {Delta}{phi} = 33 fsec. Laser system with pulse lengths in the fsec regime are commercially available, the timing stability is a major concern. We propose a multi-cell W-band photoinjector that does not require a mode locked laser system. Thereby eliminating the stability requirements at W-band. The laser pulse is allowed to be many rf periods long. In principle, the photoinjector can now be considered as a thermionic rf gun. Instead of using an alpha magnet to compress the electron bunch, which would have a detrimental effect on the transverse phase space quality due to longitudinal phase space mixing, we propose to use long pulse laser system and a pair of undulators to produce a low emittance, high current, ultra-short electron bunch for beam dynamics experiments in the 90 GHz regime.

This report contains a compilation of the results of vegetation monitoring data that were collected in the spring and summer of 2005 for the Environmental Restoration Contractor's revegetation and mitigation areas on the Hanford Site.

Accelerator mass spectrometry (AMS) is a highly sensitive analytical methodology used to quantify the content of radioisotopes, such as {sup 14}C, in a sample. The primary goals of this work were to demonstrate the utility of AMS in determining cellular [{sup 14}C]doxorubicin (DOX) concentrations and to develop a sensitive assay that is superior to high performance liquid chromatography (HPLC) for the quantification of DOX at the tumor level. In order to validate the superior sensitivity of AMS versus HPLC with fluorescence detection, we performed three studies comparing the cellular accumulation of DOX: one in vitro cell line study, and two in vivo xenograft mouse studies. Using AMS, we quantified cellular DOX content up to 4 hours following in vitro exposure at concentrations ranging from 0.2 pg/ml (345 fM) to 2 {micro}g/ml (3.45 {micro}M) [{sup 14}C]DOX. The results of this study show that, compared to standard fluorescence-based HPLC, the AMS method was over five orders of magnitude more sensitive. Two in vivo studies compared the sensitivity of AMS to HPLC using a nude mouse xenograft model in which breast cancer cells were implanted subcutaneously. After sufficiently large tumors formed, DOX was administered intravenously at two dose levels. Additionally, we tested the …

An important long-term objective of advanced nuclear fuel cycle (AFC) technologies is to provide improvement in the long-term management of radioactive waste. Compared to a once-thru fuel cycle, it is possible to generate far less waste, and potentially easier waste to manage, with advanced fuel cycles. However, the precise extent and value of these benefits are complex and difficult to quantify. This document presents a status report of efforts within AFCI Systems Analysis to define and quantify the AFC benefits to geologic disposal, development of cooperative efforts with the US repository program, and participation with international evaluations of AFC impacts on waste management. The primary analysis of repository benefits is conducted by ANL. This year repository impact evaluations have included: (1) Continued evaluation of LWR recycle benefits in support of scenario analysis. (2) Extension of repository analyses to consider long-term dose reductions. (3) Developing the opportunity for cooperation with the U.S. repository program. (4) International cooperation with OECD-NEA.

The next generation of linear colliders will require alignment accuracies and stabilities of component placement at least one, perhaps two, orders of magnitude better than can be achieved by the conventional methods and procedures in practice today. The magnitudes of these component-placement tolerances for current designs of various linear collider subsystems are tabulated. In the micron range, long-term ground motion is sufficiently rapid that on-line reference and mechanical correction systems are called for. Some recent experiences with the upgraded SLAC laser alignment systems and examples of some conceivable solutions for the future are described. The so called ''girder'' problem is discussed in the light of ambient and vibratory disturbances. The importance of the quality of the underlying geology is stressed. The necessity and limitations of particle-beam-derived placement information are mentioned.

The compression of a laser pulse by amplification of an ultra short pulse beam which seeds the stimulated Raman scatter of the first beam has been long been discussed in the context of solid and gas media. We investigate the possibility of using intersecting beams in a plasma to compress nanosecond pulses to picosecond duration by scattering from driven electron waves. Recent theoretical studies have shown the possibility of efficient compression with large amplitude, non-linear Langmuir waves driven either by SRS [1] or non-resonantly [2]. We describe experiments in which a plasma suitable for pulse compression is created, and amplification of an ultra short pulse beam is demonstrated.

The smoothness of a beam line refers to the quality of the relative positioning of a number of adjacent beam guiding components. The fact that smoothness is of highest priority when positioning magnets can be seen in the local tolerances imposed by the beam optics. In the past, smoothing has been done by separating horizontal and vertical misalignments and then applying some sort of analytical or manual ''feathering'' technique. The Stanford Linear Collider (SLC) did not easily lend itself to this sort of smoothing because of the highly coupled nature of its pitched and rolled beam line. This paper will discuss an attempt to develop a repeatable method which is independent of the inconsistencies of human judgment and can simultaneously smooth in two or more dimensions. Four major goals were defined for the smoothing algorithm used on the SLC alignment. The first, was to simultaneously model errors for both horizontal and vertical directions. Secondly, a smooth curve whose shape was suggested by the data and not by a predetermined model was implied by the fact that unknown systematic errors were being eliminated. Thirdly, this curve must be a reproducibly fit, independent of the inconsistent nature of human judgment. Fourth, the …

This paper discusses configuration scripts in general and the scripting language issues involved. A brief description of GNU autoconf is provided along with a contrasting overview of autokonf, a configuration script generator implemented in Perl, whose macros are implemented in Perl, generating a configuration script in Perl. It is very portable, easily extensible, and readily mastered.

A wealth of new measurements of hadronic B decays to open charm and charmonium have been performed on the data sample collected by the BaBar experiment at the PEP-II e{sup +}e{sup -} B-factory. We report the first measurement of the rates for inclusive charm production separately for charged and neutral B mesons. Combining measurements of the decay rate of B{sup 0} {yields} D*{sub s}{sup +}D*{sup -} obtained with a partial reconstruction technique and the complete reconstruction of B{sup 0} {yields} D*{sub s}{sup +}D*{sup -} with D{sub s}{sup +} {yields} {phi}{pi}{sup +}, we obtain the most precise measurement of {Beta}(D{sub s}{sup +} {yields} {phi}{pi}{sup +}). We present an update of the measurements of the branching fractions of exclusive B decays to J/{psi}, {psi}(2S), {chi}{sub c1}, {chi}{sub c2} and a kaon or a K*. In addition, we show preliminary results on exclusive decay rates to final states with baryons, or newly-discovered particles, such as D*{sub sJ}(2317), D{sub sJ}(2460){sup +}, and the X(3872).

The working group has identified the parameters of an afterburner based on the design of a future linear collider. The new design brings the center of mass energy of the collider from 1 to 2 TeV. The afterburner is located in the final focus section of the collider, operates at a gradient of {approx}4 GeV/m, and is only about 125 m long. Very important issues remain to be addressed, and include the physics and design of the positron side of the afterburner, as well as of the final focus system. Present plasma wakefield accelerator experiments have reached a level of maturity and of relevance to the afterburner, that make it timely to involve the high energy physics and accelerator community in the afterburner design process. The main result of this working group is the first integration of the designs of a future linear collider and an afterburner.

Beamline 7.2 of the Advanced Light Source (ALS) at theLawrence Berkeley National Laboratory (LBNL) is a beam diagnostics systemthat uses the synchrotron radiation emitted by a dipole magnet. Itconsists of two branches; in the first one the x-ray portion of theradiation is used in a pinhole camera system for measuring the transverseprofile of the beam. The second branch is equipped with an x-ray beamposition monitor (BPM) and with a multipurpose port where the visible andthe far-infrared part of the radiation can be used for variousapplications such as bunch length measurements and IR coherentsynchrotron radiation experiments. The pinhole system has been operatingsuccessfully since the end of 2003. The installation of the second branchhas been completed recently and the results of its commissioning arepresented in this paper together with examples of beam measurementsperformed at BL 7.2.

The goal of ''as-built'' computational modeling is to incorporate the most representative geometry and material information for an (fabricated or legacy) object into simulations. While most engineering finite element simulations are based on an object's idealized ''as-designed'' configuration with information obtained from technical drawings or computer-aided design models, ''as-built'' modeling uses nondestructive characterization and metrology techniques to provide the feature information. By incorporating more representative geometry and material features as initial conditions, the uncertainty in the simulation results can be reduced, providing a more realistic understanding of the event and object being modeled. In this paper, key steps and technology areas in the as-built modeling framework are: (1) inspection using non-destructive characterization (NDC) and metrology techniques; (2) data reduction (signal and image processing including artifact removal, data sensor fusion, and geometric feature extraction); and (3) engineering and physics analysis using finite element codes. We illustrate the process with a cylindrical phantom and include a discussion of the key concepts and areas that need improvement. Our results show that reasonable as-built initial conditions based on a volume overlap criteria can be achieved and that notable differences between simulations of the as-built and as-designed configurations can be observed for a given load …

The use of the Kern Me5000 as a ''stand alone'' instrument is restricted to a minimum measurement distance of approximately 20m (Kern internal ''low range'' program), with 2 display readout to the nearest 100{micro}m. Using an external program, it is possible to extend both, the display resolution to 10{micro}m, 2nd the range down to distances well below 20m. This paper attempts to explain Kern's reasoning behind the original limitation of approximately 20m, and presents the results from testing three Mekometer Me5000 instruments. Their similarities, differences, and accuracies are assessed for distances below 25m providing a comparison against the use of invar wires.

The purpose of this system description document (SDD) is to establish requirements that drive the design of the Cask/MSC/WP preparation system and their bases to allow the design effort to proceed to license application. This SDD is a living document that will be revised at strategic points as the design matures over time. This SDD identifies the requirements and describes the system design, as they exist at this time, with emphasis on those attributes of the design provided to meet the requirements. This SDD has been developed to be an engineering tool for design control. Accordingly, the primary audience and users are design engineers. This type of SDD both leads and trails the design process. It leads the design process with regard to the flow down of upper tier requirements onto the system. Knowledge of these requirements is essential in performing the design process. This SDD trails the design with regard to the description of the system. The description provided in the SDD is a reflection of the results of the design process to date. This SDD addresses the ''Project Requirements Document'' (PRD) (Canori and Leitner 2003 [DIRS 166275]) requirements. Additional PRD requirements may be cited, as applicable, to drive …

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Ion implantation into silica followed by thermal annealingis an established growth method for Si and Ge nanocrystals. Wedemonstrate that growth of Group IV semiconductor nanocrystals can besuppressed by co-implantation of oxygen prior to annealing. For Sinanocrystals, at low Si/O dose ratios, oxygen co-implantation leads to areduction of the average nanocrystal size and a blue-shift of thephotoluminescence emission energy. For both Si and Ge nanocrystals, atlarger Si/O or Ge/O dose ratios, the implanted specie is oxidized andnanocrystals do not form. This chemical deactivation was utilized toachieve patterned growth of Si and Ge nanocrystals. Si was implanted intoa thin SiO2 film on a Si substrate followed by oxygen implantationthrough an electron beam lithographically defined stencil mask. Thermalannealing of the co-implanted structure yields two-dimensionallypatterned growth of Si nanocrystals under the masked regions. We applieda previously developed process to obtain exposed nanocrystals byselective HF etching of the silica matrix to these patterned structures.Atomic force microscopy (AFM) of etched structures revealed that exposednanocrystals are not laterally displaced from their original positionsduring the etching process. Therefore, this process provides a means ofachieving patterned structures of exposed nanocrystals. The possibilitiesfor scaling this chemical-based lithography process to smaller featuresand for extending it to 3-D patterning is discussed.

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At the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory (LBNL), we are proposing the construction of CIRCE (Coherent InfraRed Center), a ring-based photon source completely optimized for the generation of coherent synchrotron radiation (CSR) in the terahertz frequency range [1]. CIRCE exploits the full complement of the CSR-production mechanisms presently available for obtaining top performance, including a photon flux exceeding by more than nine orders of magnitude that of existing ''conventional'' broadband terahertz sources.

Colloidal nanocrystals are nanometer-sized, solution-grown inorganic particles stabilized by a layer of surfactants attached to their surface. The inorganic cores exhibit useful properties controlled by composition as well as size and shape, while the surfactant coating ensures that these structures are easy to fabricate and process. It is this combination of features that makes colloidal nanocrystals attractive and promising building blocks for advanced materials and devices. But their full potential can only be exploited if we achieve exquisite control over their composition, size, shape, crystal structure and surface properties. Here we review what is known about nanocrystal growth and outline strategies for controlling it.

A method combining features of front-tracking methods and fixed-domain methods is presented to model dendritic solidification of pure materials. To explicitly track the interface growth and shape of the solidifying crystals, a fronttracking approach based on the level set method is implemented. To easily model the heat and momentum transport, a fixed-domain method is implemented assuming a diffused freezing front where the liquid fraction is defined in terms of the level set function. The fixed-domain approach, by avoiding the explicit application of essential boundary conditions on the freezing front, leads to an energy conserving methodology that is not sensitive to the mesh size. To compute the freezing front morphology, an extended Stefan condition is considered. Applications to several classical Stefan problems and two- and three-dimensional crystal growth of pure materials in an undercooled melt including the effects of melt flow are considered. The computed results agree very well with available analytical solutions as well as with results obtained using front-tracking techniques and the phase-field method.

A thermomechanical study of the effects of mold topography on the solidification of Aluminum alloys at early times is provided. The various coupling mechanisms between the solid-shell and mold deformation and heat transfer at the mold/solid-shell interface during the early stages of Aluminum solidification on molds with uneven topographies are investigated. The air-gap nucleation time, the stress evolution and the solid-shell growth pattern are examined for different mold topographies to illustrate the potential control of Aluminum cast surface morphologies during the early stages of solidification using proper design of mold topographies. The unstable shell growth pattern in the early solidification stages results mainly from the unevenness of the heat flux between the solid-shell and the mold surface. This heat flux is determined by the size of the air-gaps formed between the solidifying shell and mold surface or from the value of the contact pressure. Simulation results show that a sinusoidal mold surface with a smaller wavelength leads to nucleation of air-gaps at earlier times. In addition, the unevenness in the solid-shell growth pattern decreases faster for a smaller wavelength. Such studies can be used to tune mold surfaces for the control of cast surface morphologies.

Various results are obtained for a Friedmann-Robertson-Walker cosmology. We derive an exact equation that determines Hubble's law, clarify issues concerning the speeds of faraway objects and uncover a 'tail-light angle effect' for distant luminous sources. The latter leads to a small, previously unnoticed correction to the parallax distance formula.

Isotopic label tracing is a powerful experimental technique that can be combined with metabolic models to quantify metabolic fluxes in an organism under a particular set of growth conditions. In this work we constructed a genome-scale metabolic model of Methylobacterium extorquens, a facultative methylotroph with potential application in the production of useful chemicals from methanol. A series of labeling experiments were performed using 13C-methanol, and the resulting distribution of labeled carbon in the proteinogenic amino acids was determined by mass spectrometry. Algorithms were developed to analyze this data in context of the metabolic model, yielding flux distributions for wild-type and several engineered strains of M. extorquens. These fluxes were compared to those predicted by model simulation alone, and also integrated with microarray data to give an improved understanding of the metabolic physiology of this organism.

To incorporate symmetry properties of second-order differential equations into finite difference equations, the concept of differential-difference invariants is introduced. This concept is applied to discretizing homogeneous eigenvalue problems and inhomogeneous two-point boundary value problems with various combinations of Dirichlet, Neumann, and Robin boundary conditions. It is demonstrated that discretizations constructed with differential-difference invariants yield exact results for eigenvalue spectra and superconvergent results for numerical solutions of differential equations.