We present a first look at the new code for self-consistent, 2D simulations of beam dynamics affected by the coherent synchrotron radiation. The code is of the particle-in-cell variety: the beam bunch is sampled by point-charge particles, which are deposited on the grid; the corresponding forces on the grid are then computed using retarded potentials according to causality, and interpolated so as to advance the particles in time. The retarded potentials are evaluated by integrating over the 2D path history of the bunch, with the charge and current density at the retarded time obtained from interpolation of the particle distributions recorded at discrete timesteps. The code is benchmarked against analytical results obtained for a rigid-line bunch. We also outline the features and applications which are currently being developed.

The shielding design for the NSLS-II will provide adequate protection for the full injected beam loss in two periods of the ring around the injection point, but the remainder of the ring is shielded for lower losses of {le} 10% full beam. This will require a system to insure that beam losses don't exceed these levels for a period of time that could cause excessive radiation levels outside the shield walls. This beam containment system will measure, provide a level of control and alarm indication of the beam power losses along the beam path from the source (e-gun, linac) thru the injection system and the storage ring. This system will consist of collimators that will provide limits to (and potentially to measure) the beam miss-steering and control the loss points of the charge and monitors that will measure the average beam current losses along the beam path and alarm when this beam power loss exceeds the level set by the shielding specifications. This will require some new ideas in beam loss detection capability and collimation. The initial planning and R&D program will be presented.

The planned luminosity upgrade to LHC is likely to necessitate a large crossing angle and a local crab crossing scheme. For this scheme crab cavities align bunches prior to collision. The scheme requires at least four such cavities, a pair on each beam line either side of the interaction point (IP). Upstream cavities initiate rotation and downstream cavities cancel rotation. Cancellation is usually done at a location where the optics has re-aligned the bunch. The beam line separation near the IP necessitates a more compact design than is possible with elliptical cavities such as those used at KEK. The reduction in size must be achieved without an increase in the operational frequency to maintain compatibility with the long bunch length of the LHC. This paper proposes a suitable superconducting variant of a four rod coaxial deflecting cavity (to be phased as a crab cavity), and presents analytical models and simulations of suitable designs.

Ultra intense short pulse laser pulses incident on solid targets can generate energetic protons. In additions to their potentially important applications such as in cancer treatments and proton fast ignition, these protons are essential to understand the complex physics of intense laser plasma interaction. To better characterize these laser-produced protons, we designed and constructed a novel, spatially imaging proton spectrometer that will not only measure proton energy distribution with high resolution, but also provide its angular characteristics. The information obtained from this spectrometer compliments those from commonly used diagnostics including radiochromic film packs, CR39 nuclear track detectors, and non-imaging magnetic spectrometers. The basic characterizations and sample data from this instrument are presented.

Long range beam-beam experiments were conducted during the Run 2009 in the Yellow and the Blue beams of the RHIC accelerator with DC wires. The effects of a long-range interaction with a DC wire on colliding and non-colliding bunches with the aid of beam losses, orbits, tunes were studied. Results from distance scans and an attempt to compensate a long-range interaction with a DC wire is presented. Two DC wires in the vertical plane were installed in the RHIC accelerator in 2006 with the aim of investigating long range (LR) beam-beam effects and a potential compensation. Extensive experiments were conducted focusing mainly on the effect of a wire on single ion beams from 2006-2009. A unique opportunity to compare the effect of the wire on colliding beams and compensation of a single LR beam-beam interaction were conducted in Run2009 with protons at 100 GeV. Due to aperture considerations for decreasing {beta}*, the Blue wire was removed during the shutdown after the Run2009 and the Yellow wire is foreseen to be removed in the near future. Therefore, these experiments serve as the final set of measurements for LR beam-beam with RHIC as a test bed. The relevant RHIC beam and lattice …

Physics experiments aimed at deducing key parameters for use in a variety of programs critical to the mission of the National Laboratories require actinide targets placed onto various substrates. The target material quantity and the substrate desired depend upon the type of experiment being designed. The physicist(s) responsible for the experimental campaign will consult with the radiochemistry staff as to the feasibility of producing a desired target/substrate combination. In this report they discuss the production of U and Pu targets on very thin C and Ti substrates. The techniques used, plating cells designed for, tips, and limits is discussed.

The first phase of the project consists of four months of applied research, starting from September 1, 2005 and was completed by December 31, 2005. During this time, the project team heavily relied on highly detailed numerical modeling techniques to evaluate the feasibility of the APA technology. Specifically, (i) A GT-Power{sup TM}engine simulation model was constructed to predict engine efficiency at various operating conditions. Efficiency was defined based on the second-law thermodynamic availability. (ii) The engine efficiency map generated by the engine simulation was then fed into a simplified vehicle model, which was constructed in the Matlab/Simulink environment, to predict fuel consumption of a refuse truck on a simple collection cycle. (iii) Design and analysis work supporting the concept of retrofitting an existing Sturman Industries Hydraulic Valve Actuation (HVA) system with the modifications that are required to run the HVA system with Air Power Assist functionality. A Matlab/Simulink model was used to calculate the dynamic response of the HVA system. Computer aided design (CAD) was done in Solidworks for mechanical design and hydraulic layout. At the end of Phase I, 11% fuel economy improvement was predicted. During Phase II, the engine simulation group completed the engine mapping work. The air …

RF electron guns with a strained super lattice GaAs cathode can generate polarized electron beam of higher brightness and lower emittance than do DC guns, due to their higher field gradient at the cathode's surface. In a normal conducting RF gun, the extremely high vaccum required by these cathodes can not be met. We report on an experiment with a superconducting SRF gun, which can maintain a vacuum of nearly 10-12 torr because of cryo-pumping at the temperature of 4.2K. With conventional activation, we obtained a QE of 3% at 532 nm, with lifetime of nearly 3 days in the preparation chamber. We plan to use this cathode in a 1.3 GHz 1/2 cell SRF gun to study its performance. In addition, we studied the multipacting at the location of cathode. A new model based on the Forkker-Planck equation which can estimate the bunch length of the electron beam is discussed in this paper. Future particle accelerators such as eRHIC and ILC require high brightness, high current polarized electrons Recently, using a superlattice crystal, the maximum polarization of 95% was reached. Activation with Cs,O lowers the electron affinity and makes it energetically possible for all the electrons excited in to …

The proposed steam in let temperature in the Advanced Ultra Supercritical (A·USC) steam turbine is high enough (760°C) Ihat traditional turbine casing and valve body materials such as ferr;tic/manensitic steels will not suffice due to temperature lim itations of this class of materials. Cast versions of three traditionally wrought Ni-based superalloys (Haynes 263. Haynes 282, and Nimonic 105) were evaluated for use as casing or valve components for the next generation of industrial steam turbines. The full size castings are substantia l: 2-5,000 kg each half and on the order of 100 nun thick. Experimental castings were quite a bit smaller, but section size was retained and cooling rate controlled to produce equi valem microslruclUre •. A multi_step homogenization heat treatment was d~ve loped to better disperse the al loy constituents. These castings were subsequently evaluated by characterizing their microstructure as well as their steam oxidation resistance (al 760 and 800 "C).

Given the cost and lead-times involved in high-energy proton radiography, it is prudent to model proposed radiographic experiments to see if the images predicted would return useful information. We recently modified our raytracing transmission radiography modeling code HADES to perform simplified Monte Carlo simulations of the transport of protons in a proton radiography beamline. Beamline objects include the initial diffuser, vacuum magnetic fields, windows, angle-selecting collimators, and objects described as distorted 2D (planar or cylindrical) meshes or as distorted 3D hexahedral meshes. We present an overview of the algorithms used for the modeling and code timings for simulations through typical 2D and 3D meshes. We next calculate expected changes in image blur as scattering materials are placed upstream and downstream of a resolution test object (a 3 mm thick sheet of tantalum, into which 0.4 mm wide slits have been cut), and as the current supplied to the focusing magnets is varied. We compare and contrast the resulting simulations with the results of measurements obtained at the 800 MeV Los Alamos LANSCE Line-C proton radiography facility.

The global atmospheric concentration of CO2 has increased by more than 30percent since the industrial revolution. Although the stimulating effects of elevated CO2 (eCO2) on plant growth and primary productivity have been well studied, its influences on belowground microbial communities are poorly understood and controversial. In this study, we showed a significant change in the structure and functional potential of soil microbial communities at eCO2 in a grassland ecosystem, the BioCON (Biodiversity, CO2 and Nitrogen) experimental site (http://www.biocon.umn.edu/) using a comprehensive functional gene array, GeoChip 3.0, which contains about 28,0000 probes and covers approximately 57,000 gene variants from 292 functional gene families involved in carbon, nitrogen, phosphorus and sulfur cycles as well as other functional processes. GeoChip data indicated that the functional structure of microbial communities was markedly different between ambient CO2 (aCO2) and eCO2 by detrended correspondence analysis (DCA) of all 5001 detected functional gene probes although no significant differences were detected in the overall microbial diversity. A further analysis of 1503 detected functional genes involved in C, N, P, and S cycles showed that a considerable portion (39percent) of them were only detected under either aCO2 (14percent) or eCO2 (25percent), indicating that the functional characteristics of the microbial …

This document presents high-level architectural and system requirements for a next-generation system analysis code (NGSAC) to support reactor safety decision-making by plant operators and others, especially in the context of light water reactor plant life extension. The capabilities of NGSAC will be different from those of current-generation codes, not only because computers have evolved significantly in the generations since the current paradigm was first implemented, but because the decision-making processes that need the support of next-generation codes are very different from the decision-making processes that drove the licensing and design of the current fleet of commercial nuclear power reactors. The implications of these newer decision-making processes for NGSAC requirements are discussed, and resulting top-level goals for the NGSAC are formulated. From these goals, the general architectural and system requirements for the NGSAC are derived.

A Mono-Energetic Gamma-Ray (MEGa-Ray) Compton scattering light source is being developed at LLNL in collaboration with SLAC National Accelerator Laboratory. The electron beam for the Compton scattering interaction will be generated by a X-band RF gun and a X-band LINAC at the frequency of 11.424 GHz. High power RF in excess of 500 MW is needed to accelerate the electrons to energy of 250 MeV or greater for the interaction. Two high power klystron amplifiers, each capable of generating 50 MW, 1.5 msec pulses, will be the main high power RF sources for the system. These klystrons will be powered by state of the art solid-state high voltage modulators. A RF pulse compressor, similar to the SLED II pulse compressor, will compress the klystron output pulse with a power gain factor of five. For compactness consideration, we are looking at a folded waveguide setup. This will give us 500 MW at output of the compressor. The compressed pulse will then be distributed to the RF gun and to six traveling wave accelerator sections. Phase and amplitude control are located at the RF gun input and additional control points along the LINAC to allow for parameter control during operation. This high …

Recent experimental results have indicated that Buffered Electropolishing (BEP) is a promising candidate for the next generation of surface treatment technique for Nb superconducting radio frequency (SRF) cavities to be used in particle accelerators. In order to lay the foundation for using BEP as the next generation surface treatment technique for Nb SRF cavities, some fundamental aspects of BEP treatments for Nb have to be investigated. In this report, recent progress on BEP study at JLab is shown. Improvements on the existing vertical BEP are made to allow water cooling from outside of a Nb single cell cavity in addition to cooling provided by acid circulation so that the temperature of the cavity can be stable during processing. Some investigation on the electrolyte mixture was performed to check the aging effect of the electrolyte. It is shown that good polishing results can still be obtained on Nb at a current density of 171 mA/cm when the BEP electrolyte was at the stationary condition and was more than 1.5 years old.

Progress made in ALICE (Accelerators and Lasers In Combined Experiments) commissioning and a summary of the latest experimental results are presented in this paper. After an extensive work on beam loading effects in SC RF linac (booster) and linac cavities conditioning, ALICE can now operate in full energy recovery mode at the bunch charge of 40pC, the beam energy of 30MeV and train lengths of up to 100us. This improved operation of the machine resulted in generation of coherently enhanced broadband THz radiation with the energy of several tens of uJ per pulse and in successful demonstration of the Compton Backscattering x-ray source experiment. The next steps in the ALICE scientific programme are commissioning of the IR FEL and start of the research on the first non-scaling FFAG accelerator EMMA. Results from both projects will be also reported.

The 3rd LHC Crab Cavity workshop (LHC-CC09) took place at CERN in October 2009. It reviewed the current status and identified a clear strategy towards a future crab-cavity implementation. Following the success of crab cavities in KEK-B and the strong potential for luminosity gain and leveling, CERN will pursue crab crossing for the LHC upgrade. We present a summary and outcome of the variousworkshop sessions which have led to the LHC crab-cavity strategy, covering topics like layout, cavity design, integration, machine protection, and a potential validation test in the SPS.

The planned luminosity upgrade to LHC is likely to necessitate a large crossing angle and a local crab crossing scheme. For this scheme crab cavities align bunches prior to collision. The scheme requires at least four such cavities, a pair on each beam line either side of the interaction point (IP). Upstream cavities initiate rotation and downstream cavities cancel rotation. Cancellation is usually done at a location where the optics has re-aligned the bunch. The beam line separation near the IP necessitates a more compact design than is possible with elliptical cavities such as those used at KEK. The reduction in size must be achieved without an increase in the operational frequency to maintain compatibility with the long bunch length of the LHC. This paper proposes a suitable superconducting variant of a four rod coaxial deflecting cavity (to be phased as a crab cavity), and presents analytical models and simulations of suitable designs.

Heat pump clothes dryers (HPCDs) can be as much as 50percent more energy-efficient than conventional electric resistance clothes dryers, and therefore have the potential to save substantial amounts of electricity. While not currently available in the U.S., there are manufacturers in Europe and Japan that produce units for those markets. Drawing on analysis conducted for the U.S. Department of Energy's (DOE) current rulemaking on amended standards for clothes dryers, this paper evaluates the cost-effectiveness of HPCDs in American homes, as well as the national impact analysis for different market share scenarios. In order to get an accurate measurement of real energy savings potential, the paper offers a new energy use calculation methodology that takes into account the most current data on clothes washer cycles, clothes dryer usage frequency, remaining moisture content, and load weight per cycle, which is very different from current test procedure values. Using the above methodology along with product cost estimates developed by DOE, the paper presents the results of a life-cycle cost analysis of the adoption of HPCDs in a representative sample of American homes. The results show that HPCDs have positive economic benefits only for households with high clothes dryer usage or for households with …

Microbiomes play very important roles in terms of nutrition, health and disease by interacting with their hosts. Based on sequence data currently available in public domains, we have developed a functional gene array to monitor both organismal and functional gene profiles of normal microbiota in human and mouse hosts, and such an array is called human and mouse microbiota array, HMM-Chip. First, seed sequences were identified from KEGG databases, and used to construct a seed database (seedDB) containing 136 gene families in 19 metabolic pathways closely related to human and mouse microbiomes. Second, a mother database (motherDB) was constructed with 81 genomes of bacterial strains with 54 from gut and 27 from oral environments, and 16 metagenomes, and used for selection of genes and probe design. Gene prediction was performed by Glimmer3 for bacterial genomes, and by the Metagene program for metagenomes. In total, 228,240 and 801,599 genes were identified for bacterial genomes and metagenomes, respectively. Then the motherDB was searched against the seedDB using the HMMer program, and gene sequences in the motherDB that were highly homologous with seed sequences in the seedDB were used for probe design by the CommOligo software. Different degrees of specific probes, including gene-specific, …

Medicine Lake Volcano is a Quaternary shield volcano located in a tectonically complex and active zone at the transition between the Basin and Range Province and the Cascade Range of the Pacific Province. The volcano is topped by a 7x12 km elliptical depression surrounded by a discontinuous constructional ring of basaltic to rhyolitic lava flows. This thesis explores the possibility that the depression may have formed due to regional extension (rift basin) or dextral shear (pull-apart basin) rather than through caldera collapse and examines the relationship between regional tectonics and localized volcanism. Existing data consisting of temperature and magnetotelluric surveys, alteration mineral studies, and core logging were compiled and supplemented with additional core logging, field observations, and fault striae studies in paleomagnetically oriented core samples. These results were then synthesized with regional fault data from existing maps and databases. Faulting patterns near the caldera, extension directions derived from fault striae P and T axes, and three-dimensional temperature and alteration mineral models are consistent with slip across arcuate ring faults related to magma chamber deflation during flank eruptions and/or a pyroclastic eruption at about 180 ka. These results are not consistent with a rift or pull-apart basin. Limited subsidence can be …

Within the Neutrino Factory Project the muon acceleration process involves a complex chain of accelerators including a (single-pass) linac, two recirculating linacs and an FFAG. The linac consists of RF cavities and iron shielded solenoids for transverse focusing and has been previously designed relying on idealized field models. However, to predict accurately the transport and acceleration of a high emittance 30 cm wide beam with 10 % energy spread requires detailed knowledge of fringe field distributions. This article presents results of the front-to-end tracking of the muon beam through numerically simulated realistic field distributions for the shielded solenoids and the RF fields. Real and phase space evolution of the beam has been studied along the linac and the results are presented and discussed.

For elastically noninteracting vertical-fracture sets at arbitrary orientation angles to each other, a detailed model is presented in which the resulting anisotropic fractured medium generally has orthorhombic symmetry overall. Some of the analysis methods and ideas of Schoenberg are emphasized, together with their connections to other similarly motivated and conceptually related methods by Sayers and Kachanov, among others. Examples show how parallel vertical-fracture sets having HTI (horizontal transversely isotropic) symmetry transform into orthotropic fractured media if some subsets of the vertical fractures are misaligned with the others, and then the fractured system can have VTI (vertical transversely isotropic) symmetry if all of the fractures are aligned randomly or half parallel and half perpendicular to a given vertical plane. An orthotropic example having vertical fractures in an otherwise VTI earth system (studied previously by Schoenberg and Helbig) is compared with the other examples treated and it is finally shown how fluids in the fractures affect the orthotropic poroelastic system response to seismic waves. The key result is that fracture-influence parameters are multiplied by a factor of (1-B), where 0 {le} B < 1 is Skempton's second coefficient for poroelastic media. Skempton's B coefficient is itself a measurable characteristic of fluid-saturated porous …

Many efforts were made over the last decades to develop a better polarized electron source for the high energy physics. Several laboratories operate DC guns with the Gallium-Arsenide photo-cathode, which yield a highly polarized electron beam. However, the beam's emittance might well be improved using a Superconducting RF electron gun, which delivers beams of higher brightness than DC guns does, because the field gradient at the cathode is higher. SRF guns with metal cathodes and CsTe cathodes have been tested successfully. To produce polarized electrons, a Gallium-Arsenide photo-cathode must be used: an experiment to do so in a superconducting RF gun is under way at BNL. Since the cathode will be normal conducting, the problem about the heat load stemming from the cathode arises. We present our measurements of the electrical resistance of GaAs at cryogenic temperatures, a prediction of the heat load and the verification by measuring the quality factor of the gun with and without cathode.

A replacement for the PS storage ring is being considered, in the context of the future LHC accelerator complex upgrade, that would likely place the new machine (the PS2) in a regime where the electron-cloud (EC) effect might be significant. We report here our current estimate of the EC density ne in the bending magnets and the field-free regions at injection and extraction beam energy, for both proposed bunch spacings, tb = 25 and 50 ns. The primary model parameters exercised are the peak secondary emission yield (SEY) delta max, the electron-wall impact energy at which the SEY peaks, Emax, and the chamber radius a in the fieldfree regions. We present many of our results as a function of the bunch intensity Nb, and we provide a tentative explanation for the non-monotonic behavior of ne as a function of Nb.