Sample records for loaded accelerating structure

  1. Experimental Study of the Effect of Beam Loading on RF Breakdown Rate in CLIC High-Gradient Accelerating Structures

    E-Print Network [OSTI]

    Tecker, F; Kelisani, M; Doebert, S; Grudiev, A; Quirante, J; Riddone, G; Syratchev, I; Wuensch, W; Kononenko, O; Solodko, A; Lebet, S

    2013-01-01T23:59:59.000Z

    RF breakdown is a key issue for the multi-TeV highluminosity e+e- Compact Linear Collider (CLIC). Breakdowns in the high-gradient accelerator structures can deflect the beam and decrease the desired luminosity. The limitations of the accelerating structures due to breakdowns have been studied so far without a beam present in the structure. The presence of the beam modifies the distribution of the electrical and magnetic field distributions, which determine the breakdown rate. Therefore an experiment has been designed for high power testing a CLIC prototype accelerating structure with a beam present in the CLIC Test Facility (CTF3). A special beam line allows extracting a beam with nominal CLIC beam current and duration from the CTF3 linac. The paper describes the beam optics design for this experimental beam line and the commissioning of the experiment with beam.

  2. Development of an Accelerated Ash-Loading Protocol for Diesel...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    an Accelerated Ash-Loading Protocol for Diesel Particulate Filters Development of an Accelerated Ash-Loading Protocol for Diesel Particulate Filters Poster presentation at the 2007...

  3. Plasma-based accelerator structures

    SciTech Connect (OSTI)

    Schroeder, Carl B.

    1999-12-01T23:59:59.000Z

    Plasma-based accelerators have the ability to sustain extremely large accelerating gradients, with possible high-energy physics applications. This dissertation further develops the theory of plasma-based accelerators by addressing three topics: the performance of a hollow plasma channel as an accelerating structure, the generation of ultrashort electron bunches, and the propagation of laser pulses is underdense plasmas.

  4. EXPERIMENTAL DEMONSTRATION OF WAKEFIELD EFFECTS IN A 250 GHZ PLANAR DIAMOND ACCELERATING STRUCTURE*

    E-Print Network [OSTI]

    Brookhaven National Laboratory

    of a rectangular waveguide loaded with polycrystalline CVD diamond plates as an accelerating structure. It should polycrystalline diamond plates loaded in a 6 cm long waveguide (Fig. 2). The beam gap was 200 microns (Fig. TM11EXPERIMENTAL DEMONSTRATION OF WAKEFIELD EFFECTS IN A 250 GHZ PLANAR DIAMOND ACCELERATING STRUCTURE

  5. Photonic Crystal Laser-Driven Accelerator Structures

    SciTech Connect (OSTI)

    Cowan, Benjamin M.

    2007-08-22T23:59:59.000Z

    Laser-driven acceleration holds great promise for significantly improving accelerating gradient. However, scaling the conventional process of structure-based acceleration in vacuum down to optical wavelengths requires a substantially different kind of structure. We require an optical waveguide that (1) is constructed out of dielectric materials, (2) has transverse size on the order of a wavelength, and (3) supports a mode with speed-of-light phase velocity in vacuum. Photonic crystals---structures whose electromagnetic properties are spatially periodic---can meet these requirements. We discuss simulated photonic crystal accelerator structures and describe their properties. We begin with a class of two-dimensional structures which serves to illustrate the design considerations and trade-offs involved. We then present a three-dimensional structure, and describe its performance in terms of accelerating gradient and efficiency. We discuss particle beam dynamics in this structure, demonstrating a method for keeping a beam confined to the waveguide. We also discuss material and fabrication considerations. Since accelerating gradient is limited by optical damage to the structure, the damage threshold of the dielectric is a critical parameter. We experimentally measure the damage threshold of silicon for picosecond pulses in the infrared, and determine that our structure is capable of sustaining an accelerating gradient of 300 MV/m at 1550 nm. Finally, we discuss possibilities for manufacturing these structures using common microfabrication techniques.

  6. Photonic Crystal Laser-Driven Accelerator Structures

    SciTech Connect (OSTI)

    Cowan, B.; /SLAC

    2005-09-19T23:59:59.000Z

    We discuss simulated photonic crystal structure designs for laser-driven particle acceleration, focusing on three-dimensional planar structures based on the so-called ''woodpile'' lattice. We demonstrate guiding of a speed-of-light accelerating mode by a defect in the photonic crystal lattice and discuss the properties of this mode. We also discuss particle beam dynamics in the structure, presenting a novel method for focusing the beam. In addition we describe some potential coupling methods for the structure.

  7. Wind induced torsional loads on structures

    E-Print Network [OSTI]

    Kareem, Ahsan

    Wind induced torsional loads on structures A. Kareem Department of Civil Engineering, University degrees of freedom. If the resultant wind forces do not coincide with the centre of mass at each floor is also sensitive to the ratio of torsional to translational frequencies. There is no existing wind load

  8. Variable energy constant current accelerator structure

    DOE Patents [OSTI]

    Anderson, O.A.

    1988-07-13T23:59:59.000Z

    A variable energy, constant current ion beam accelerator structure is disclosed comprising an ion source capable of providing the desired ions, a pre-accelerator for establishing an initial energy level, a matching/pumping module having means for focusing means for maintaining the beam current, and at least one main accelerator module for continuing beam focus, with means capable of variably imparting acceleration to the beam so that a constant beam output current is maintained independent of the variable output energy. In a preferred embodiment, quadrupole electrodes are provided in both the matching/pumping module and the one or more accelerator modules, and are formed using four opposing cylinder electrodes which extend parallel to the beam axis and are spaced around the beam at 90/degree/ intervals with opposing electrodes maintained at the same potential. 12 figs., 3 tabs.

  9. Variable energy constant current accelerator structure

    DOE Patents [OSTI]

    Anderson, Oscar A. (Berkeley, CA)

    1990-01-01T23:59:59.000Z

    A variable energy, constant current ion beam accelerator structure is disclosed comprising an ion source capable of providing the desired ions, a pre-accelerator for establishing an initial energy level, a matching/pumping module having means for focusing means for maintaining the beam current, and at least one main accelerator module for continuing beam focus, with means capable of variably imparting acceleration to the beam so that a constant beam output current is maintained independent of the variable output energy. In a preferred embodiment, quadrupole electrodes are provided in both the matching/pumping module and the one or more accelerator modules, and are formed using four opposing cylinder electrodes which extend parallel to the beam axis and are spaced around the beam at 90.degree. intervals with opposing electrodes maintained at the same potential. Adjacent cylinder electrodes of the quadrupole structure are maintained at different potentials to thereby reshape the cross section of the charged particle beam to an ellipse in cross section at the mid point along each quadrupole electrode unit in the accelerator modules. The beam is maintained in focus by alternating the major axis of the ellipse along the x and y axis respectively at adjacent quadrupoles. In another embodiment, electrostatic ring electrodes may be utilized instead of the quadrupole electrodes.

  10. The grating as an accelerating structure

    SciTech Connect (OSTI)

    Fernow, R.C.

    1991-02-01T23:59:59.000Z

    This report considers the use of a diffraction grating as an accelerating structure for charged particle beams. We examine the functional dependence of the electromagnetic fields above the surface of a grating. Calculations are made of the strength of the accelerating modes for structures with {pi} and 2{pi} phase advance per period and for incident waves polarized with either the E or H vector along the grooves of the grating. We consider examples of using gratings in a laser linac and in a grating lens. We also briefly examine previous results published about this subject. 36 refs.

  11. Optimal Design of Motor and Gear for Drives with High Acceleration and Load Torque

    E-Print Network [OSTI]

    Paderborn, Universität

    Optimal Design of Motor and Gear for Drives with High Acceleration and Load Torque H. Grotstollen-acceleration product are transmitted unchanged by an ideal gear. At a first step those motors can be selected which offer sufficient rated power and power rate. When designing gears for each of these motors two ranges

  12. Dielectric-Lined High-Gradient Accelerator Structure

    SciTech Connect (OSTI)

    Jay L. Hirshfield

    2012-04-24T23:59:59.000Z

    Rectangular particle accelerator structures with internal planar dielectric elements have been studied, with a view towards devising structures with lower surface fields for a given accelerating field, as compared with structures without dielectrics. Success with this concept is expected to allow operation at higher accelerating gradients than otherwise on account of reduced breakdown probabilities. The project involves studies of RF breakdown on amorphous dielectrics in test cavities that could enable high-gradient structures to be built for a future multi-TeV collider. The aim is to determine what the limits are for RF fields at the surfaces of selected dielectrics, and the resulting acceleration gradient that could be achieved in a working structure. The dielectric of principal interest in this study is artificial CVD diamond, on account of its advertised high breakdown field ({approx}2 GV/m for dc), low loss tangent, and high thermal conductivity. Experimental studies at mm-wavelengths on materials and structures for achieving high acceleration gradient were based on the availability of the 34.3 GHz third-harmonic magnicon amplifier developed by Omega-P, and installed at the Yale University Beam Physics Laboratory. Peak power from the magnicon was measured to be about 20 MW in 0.5 {micro}s pulses, with a gain of 54 dB. Experiments for studying RF high-field effects on CVD diamond samples failed to show any evidence after more than 10{sup 5} RF pulses of RF breakdown up to a tangential surface field strength of 153 MV/m; studies at higher fields were not possible due to a degradation in magnicon performance. A rebuild of the tube is underway at this writing. Computed performance for a dielectric-loaded rectangular accelerator structure (DLA) shows highly competitive properties, as compared with an existing all-metal structure. For example, comparisons were made of a DLA structure having two planar CVD diamond elements with a all-metal CERN structure HDS operating at 30 GHz. It was shown that the ratio of maximum surface electric field to accelerating field at the metal wall is only 0.35-0.4 for DLA, much smaller than the value 2.2 for HDS; and the ratio of surface magnetic field to accelerating field is 3.0 mA/V for DLA, compared with 3.45 mA/V for HDS. These values bode well for DLA in helping to avoid breakdown and to reducing pulsed surface heating and fatigue. The shunt impedance is found to be 160-175 M{Omega}/m for DLA, as compared to 99 M{Omega}/m for HDS. Conclusions are reached from this project that CVD diamond appears promising as a dielectric with a high threshold for RF breakdown, and that rectangular accelerator structures can be devised using planar CVD diamond elements that could be operated at higher acceleration gradients with low probability of RF breakdown, as compared with corresponding all-metallic structures.

  13. Structural loading of cross deck connections for trimaran vessels

    E-Print Network [OSTI]

    Rhoads, Jason L

    2004-01-01T23:59:59.000Z

    This work investigates the fundamental relationships of wave loading on cross deck structures for trimaran vessels. In contrast with a monohull ship, trimaran vessels experience several possible structural loading cases ...

  14. Emission Control Technology, Performance/Durability -POSTER Effect of Accelerated Ash Loading on Performance of Diesel

    E-Print Network [OSTI]

    Pennycook, Steve

    on Performance of Diesel Particulate Filters and Morphology of Ash Layers Bruce G. Bunting and Todd J. Toops using a single-cylinder diesel engine has been developed for accelerated ash loading in catalyzed and non- catalyzed diesel particular filters (DPF) made of cordierite, SiC and mullite substrate

  15. Accelerator structure bead pull measurement at SLAC

    E-Print Network [OSTI]

    Lewandowski, J R; Miller, R H; Wang, J W

    2004-01-01T23:59:59.000Z

    Microwave measurement and tuning of accelerator structures are important issues for the current and next generation of high energy physics machines. Application of these measurements both before and after high power processing can reveal information about the structure but may be misinterpreted if measurement conditions are not carefully controlled. For this reason extensive studies to characterize the microwave measurements at have been made at SLAC. For the beadpull a reproducible measurement of less than 1 degree of phase accuracy in total phase drift is needed in order to resolve issues such as phase changes due to structure damage during high power testing. Factors contributing to measurement errors include temperature drift, mechanical vibration, and limitations of measurement equipment such as the network analyzer. Results of this continuing effort will be presented.

  16. RF properties of periodic accelerating structures for linear colliders

    SciTech Connect (OSTI)

    Wang, J.W.

    1989-07-01T23:59:59.000Z

    With the advent of the SLAC electron-positron linear collider (SLC) in the 100 GeV center-of-mass energy range, research and development work on even higher energy machines of this type has started in several laboratories in the United States, Europe, the Soviet Union and Japan. These linear colliders appear to provide the only promising approach to studying e/sup /plus//e/sup /minus// physics at center-of-mass energies approaching 1 TeV. This thesis concerns itself with the study of radio frequency properties of periodic accelerating structures for linear colliders and their interaction with bunched beams. The topics that have been investigated are: experimental measurements of the energy loss of single bunches to longitudinal modes in two types of structures, using an equivalent signal on a coaxial wire to simulate the beam; a method of canceling the energy spread created within a single bunch by longitudinal wakefields, through appropriate shaping of the longitudinal charge distribution of the bunch; derivation of the complete transient beam-loading equation for a train of bunches passing through a constant-gradient accelerator section, with application to the calculation and minimization of multi-bunch energy spread; detailed study of field emission and radio frequency breakdown in disk-loaded structures at S-, C- and X-band frequencies under extremely high-gradient conditions, with special attention to thermal effects, radiation, sparking, emission of gases, surface damage through explosive emission and its possible control through RF-gas processing. 53 refs., 49 figs., 9 tabs.

  17. Used Nuclear Fuel Loading and Structural Performance Under Normal...

    Energy Savers [EERE]

    Used Nuclear Fuel Loading and Structural Performance Under Normal Conditions of Transport - Demonstration of Approach and Results of Used Fuel Performance Characterization Used...

  18. Numerical Simulation of Wave Loads on Static Offshore Structures

    E-Print Network [OSTI]

    of Wave Loads on Static Offshore Structures ­ p. #12;VOF Free Surface Flow Model Modelling of Free Surface-cell resolution of prescribed wave forms in relaxation zones · Support for dynamic mesh with 6-DOF solver meshNumerical Simulation of Wave Loads on Static Offshore Structures Hrvoje Jasak, Inno Gatin, Vuko

  19. R&D of Accelerator Structures at SLAC

    SciTech Connect (OSTI)

    Wang, J.W.; /SLAC

    2007-01-17T23:59:59.000Z

    The research activities for accelerator structures at SLAC are reviewed including the achievement via the main linac design for the Next Linear Collider (NLC), the program adjustment after the decision of the International Linear Collider (ILC) to be based on superconducting technology, and the work progress for the ILC, photon science at SLAC and basic accelerator structure studies.

  20. Structural load inventory database for the Kansas City federal complex

    SciTech Connect (OSTI)

    Hashimoto, P.S.; Johnson, M.W.; Nakaki, D.K. [EQE International, Inc., Irvine, CA (United States); Lynch, D.T.; Drury, M.A. [AlliedSignal Inc., Kansas City, MO (United States). Kansas City Division

    1995-12-01T23:59:59.000Z

    A structural load inventory database (LID) has been developed to support configuration management at the DOE Kansas City Plant (KCP). The objective of the LID is to record loads supported by the plant structures and to provide rapid assessments of the impact of future facility modifications on structural adequacy. Development of the LID was initiated for the KCP`s Main Manufacturing Building. Field walkdowns were performed to determine all significant loads supported by the structure, including the weight of piping, service equipment, etc. These loads were compiled in the LID. Structural analyses for natural phenomena hazards were performed in accordance with UCRL-15910. Software to calculate demands on the structural members due to gravity loads, total demands including both gravity and seismic loads, and structural member demand-to-capacity ratios were also developed and integrated into the LID. Operation of the LID is menu-driven. The LID user has options to review and print existing loads and corresponding demand-to-capacity ratios, and to update the supported loads and demand-to-capacity ratios for any future facility modifications.

  1. Structural evaluation of the 2736Z Building for seismic loads

    SciTech Connect (OSTI)

    Giller, R.A.

    1994-09-23T23:59:59.000Z

    The 2736Z building structure is evaluated for high-hazard loads. The 2736Z building is analyzed herein for normal and seismic loads and is found to successfully meet the guidelines of UCRL-15910 along with the related codes requirements.

  2. Nitrogen heat treatments of superconducting niobium radio frequency cavities: a pathway to highly efficient accelerating structures

    E-Print Network [OSTI]

    Grassellino, A; Melnychuk, O; Trenikhina, Y; Crawford, A; Rowe, A; Wong, M; Sergatskov, D; Khabiboulline, T; Barkov, F

    2013-01-01T23:59:59.000Z

    We report the experimental finding of a new surface treatment that systematically improves the quality factor of niobium radio frequency cavities for particle acceleration. A combination of annealing in a partial pressure of nitrogen and subsequent electropolishing of the niobium cavity surface leads to extremely low values of the cavities microwave surface resistance, and an improvement in the efficiency of these accelerating structures up to a factor of 3 compared to standard surface treatments, significantly reducing the cryogenic load of SRF cavities for both pulsed and continuous duty cycles. The field dependence of the Mattis-Bardeen/BCS surface resistance RBCS is reversed compared to that of standard chemically polished niobium with dRBCS/dB < 0 in the full range of investigated fields. This treatment can lead to even larger efficiency gains at increasing operating frequencies, and potentially to even larger cost savings by reducing the size of the accelerating structures.

  3. Experimental study of photonic band gap accelerator structures

    E-Print Network [OSTI]

    Marsh, Roark A

    2009-01-01T23:59:59.000Z

    This thesis reports theoretical and experimental research on a novel accelerator concept using a photonic bandgap (PBG) structure. Major advances in higher order mode (HOM) damping are required for the next generation of ...

  4. accelerator structural materials: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    accelerator structural materials First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 EM characterization of...

  5. JOURNAL OF STRUCTURAL ENGINEERING / AUGUST 2000 / 989 EQUIVALENT STATIC BUFFETING LOADS ON STRUCTURES

    E-Print Network [OSTI]

    Kareem, Ahsan

    wind loading used in design is equal to the mean wind force multiplied by the GLF. Although on structures is treated as the mean wind force multiplied by the GLF as follows: ^ ¯P(z) = GP(z) (1) where force, differs significantly from the inertial wind loading that is related to the mass and mode shape

  6. Engineering Design of a Multipurpose X-band Accelerating Structure

    E-Print Network [OSTI]

    Gudkov, Dmitry; Samoshkin, Alexander; Zennaro, Riccardo; Dehler, Micha; Raguin, Jean-Yves

    2010-01-01T23:59:59.000Z

    Both FEL projects, SwissFEL and Fermi-Elettra each require an X-band RF accelerating structure for optimal bunch compression at the respective injectors. As the CLIC project is pursuing a program for producing and testing the X-band high-gradient RF structures, a collaboration between PSI, Elettra and CERN has been established to build a multipurpose X-band accelerating structure. This paper focuses on its engineering design, which is based on the disked cells jointed together by diffusion bonding. Vacuum brazing and laser beam welding is used for auxiliary components. The accelerating structure consists of two coupler subassemblies, 73 disks and includes a wakefield monitor and diagnostic waveguides. The engineering study includes the external cooling system, consisting of two parallel cooling circuits and an RF tuning system, which allows phase advance tuning of the cell by deforming the outer wall. The engineering solution for the installation and sealing of the wake field monitor feed-through devices that...

  7. Theory of factors limiting high gradient operation of warm accelerating structures

    SciTech Connect (OSTI)

    Nusinovich, Gregory S. [University of Maryland; Antonsen, Thomas M. [University of Maryland; Kishek, Rami [University of Maryland

    2014-07-25T23:59:59.000Z

    This final report summarizes the research performed during the time period from 8/1/2010 to 7/31/2013. It consists of two parts describing our studies in two directions: (a) analysis of factors limiting operation of dielectric-loaded accelerating (DLA) structures where the main problem is the occurrence of multipactor on dielectric surfaces, and (b) studies of effects associated with either RF magnetic or RF electric fields which may cause the RF breakdown in high-gradient metallic accelerating structures. In the studies of DLA structures, at least, two accomplishments should be mentioned: the development of a 3D non-stationary, self-consistent code describing the multipactor phenomena and yielding very good agreement with some experimental data obtained in joint ANL/NRL experiments. In the metallic structures, such phenomena as the heating and melting of micro-particles (metallic dust) by RF electric and magnetic fields in single-shot and rep-rate regimes is analyzed. Also, such processes in micro-protrusions on the structure surfaces as heating and melting due to the field emitted current and the Nottingham effect are thoroughly investigated with the account for space charge of emitted current on the field emission from the tip.

  8. Design of Accelerator Online Simulator Server Using Structured Data

    SciTech Connect (OSTI)

    Shen, Guobao; /Brookhaven; Chu, Chungming; /SLAC; Wu, Juhao; /SLAC; Kraimer, Martin; /Argonne

    2012-07-06T23:59:59.000Z

    Model based control plays an important role for a modern accelerator during beam commissioning, beam study, and even daily operation. With a realistic model, beam behaviour can be predicted and therefore effectively controlled. The approach used by most current high level application environments is to use a built-in simulation engine and feed a realistic model into that simulation engine. Instead of this traditional monolithic structure, a new approach using a client-server architecture is under development. An on-line simulator server is accessed via network accessible structured data. With this approach, a user can easily access multiple simulation codes. This paper describes the design, implementation, and current status of PVData, which defines the structured data, and PVAccess, which provides network access to the structured data.

  9. TEMPERATURE AND LOAD EFFECTS ON ACOUSTIC EMISSION SIGNALS FOR STRUCTURAL HEALTH MONITORING APPLICATIONS

    E-Print Network [OSTI]

    Boyer, Edmond

    TEMPERATURE AND LOAD EFFECTS ON ACOUSTIC EMISSION SIGNALS FOR STRUCTURAL HEALTH MONITORING. KEYWORDS : Structural Health Monitoring, Acoustic Emission, Environmental and Operational Conditions2014 Author manuscript, published in "EWSHM - 7th European Workshop on Structural Health Monitoring

  10. Improved Load Distribution for Load Rating of Low-Fill Box Structures

    E-Print Network [OSTI]

    Acharya, Raju

    2012-12-31T23:59:59.000Z

    . The distribution of live loads on the top slab of a box culvert plays a major role in determining the rating factor of the culvert. The current AASHTO guidelines do not consider the effects of pavements present above the fill while determining the load distribution...

  11. A THz Coaxial Two-Channel Dielectric Wakefield Structure for High Gradient Acceleration

    SciTech Connect (OSTI)

    Marshall, T. C. [Columbia University, New York, NY (United States); Omega-P, Inc., New Haven, CT (United States); Sotnikov, G. V. [Omega-P, Inc., New Haven, CT (United States); NSC Kharkov Institute of Physics and Technology, Kharkov (Ukraine); Hirshfield, J. L. [Omega-P, Inc., New Haven, CT (United States); Yale University, New Haven, CT (United States)

    2010-11-04T23:59:59.000Z

    A coaxial two-channel dielectric wakefield structure is examined for use as a high gradient accelerator. A THz design, having radius {approx}1 mm, is shown to provide GeV/m--level acceleration gradient, high transformer ratio, and stable accelerated bunch motion when excited by a stable-moving 5-GeV 6-nC annular drive bunch.

  12. Demonstrating Structural Adequacy of Nuclear Power Plant Containment Structures for Beyond Design-Basis Pressure Loadings

    SciTech Connect (OSTI)

    Braverman, J.I.; Morante, R.

    2010-07-18T23:59:59.000Z

    ABSTRACT Demonstrating the structural integrity of U.S. nuclear power plant (NPP) containment structures, for beyond design-basis internal pressure loadings, is necessary to satisfy Nuclear Regulatory Commission (NRC) requirements and performance goals. This paper discusses methods for demonstrating the structural adequacy of the containment for beyond design-basis pressure loadings. Three distinct evaluations are addressed: (1) estimating the ultimate pressure capacity of the containment structure (10 CFR 50 and US NRC Standard Review Plan, Section 3.8) ; (2) demonstrating the structural adequacy of the containment subjected to pressure loadings associated with combustible gas generation (10 CFR 52 and 10 CFR 50); and (3) demonstrating the containment structural integrity for severe accidents (10 CFR 52 as well as SECY 90-016, SECY 93-087, and related NRC staff requirements memoranda (SRMs)). The paper describes the technical basis for specific aspects of the methods presented. It also presents examples of past issues identified in licensing activities related to these evaluations.

  13. Towards A Structural Load Testing Tool CheerSun D. Yang and Lori L. Pollock

    E-Print Network [OSTI]

    Pollock, Lori L.

    by the tester within an operational profile. This method of load testing is applied at system inte­ gration timeTowards A Structural Load Testing Tool Cheer­Sun D. Yang and Lori L. Pollock Department of Computer and Information Sciences University of Delaware Newark, DE 19716 (302) 831­1953 Abstract Load sensitive faults

  14. Experimental study on the thorium-loaded accelerator-driven system at the Kyoto Univ. critical assembly

    SciTech Connect (OSTI)

    Pyeon, C. H.; Yagi, T.; Lim, J. Y.; Misawa, T. [Nuclear Science Engineering Div., Research Reactor Inst., Kyoto Univ., Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka 590-0494 (Japan)

    2012-07-01T23:59:59.000Z

    The experimental study on the thorium-loaded accelerator-driven system (ADS) is conducted in the Kyoto Univ. Critical Assembly (KUCA). The experiments are carried out in both the critical and subcritical states for attaining the reaction rates of the thorium capture and fission reactions. In the critical system, the thorium plate irradiation experiment is carried out for the thorium capture and fission reactions. From the results of the measurements, the thorium fission reactions are obtained apparently in the critical system, and the C/E values of reaction rates show the accuracy of relative difference of about 30%. In the ADS experiments with 14 MeV neutrons and 100 MeV protons, the subcritical experiments are carried out in the thorium-loaded cores to obtain the capture reaction rates through the measurements of {sup 115}In(n, {gamma}){sup 116m}In reactions. The results of the experiments reveal the difference between the reaction rate distributions for the change in not only the neutron spectrum but also the external neutron source. The comparison between the measured and calculated reaction rate distributions demonstrates a discrepancy of the accuracy of reaction rate analyses of thorium capture reactions through the thorium-loaded ADS experiments with 14 MeV neutrons. Hereafter, kinetic experiments are planned to be carried out to deduce the delayed neutron decay constants and subcriticality using the pulsed neutron method. (authors)

  15. Shell-Based Support Structures for Nb3Sn Accelerator Quadrupole Magnets

    E-Print Network [OSTI]

    Ferracin, Paolo

    2010-01-01T23:59:59.000Z

    similarly to the outer shell, they significantly increasedof Technology Quadrupole Shell (TQS) Magnet Models forSHELL-BASED SUPPORT STRUCTURES FOR NB 3 SN ACCELERATOR

  16. Development of High-Gradient Dielectric Laser-Driven Particle Accelerator Structures

    SciTech Connect (OSTI)

    Byer, Robert L.

    2013-11-07T23:59:59.000Z

    The thrust of Stanford's program is to conduct research on high-gradient dielectric accelerator structures driven with high repetition-rate, tabletop infrared lasers. The close collaboration between Stanford and SLAC (Stanford Linear Accelerator Center) is critical to the success of this project, because it provides a unique environment where prototype dielectric accelerator structures can be rapidly fabricated and tested with a relativistic electron beam.

  17. Two Channel Dielectric-Lined Rectangular High Transformer Ratio Accelerator Structure Experiment

    SciTech Connect (OSTI)

    Shchelkunov, S. V.; LaPointe, M. A. [Beam Physics Laboratory, Yale University, 272 Whitney Avenue, New Haven, CT 06511 (United States); Hirshfield, J. L. [Beam Physics Laboratory, Yale University, 272 Whitney Avenue, New Haven, CT 06511 (United States); Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States); Marshall, T. C. [Columbia University, New York, NY 10027 (United States); Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States); Sotnikov, G. [NSC Kharkov Institute of Physics and Technology, Kharkov (Ukraine); Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States); Gai, Wei; Conde, M.; Power, J.; Mihalcea, D. [Argonne National Laboratory, Argonne, IL 60439 (United States)

    2010-11-04T23:59:59.000Z

    Current status of a two-channel cm-scale rectangular dielectric lined wakefield accelerator structure is described. This structure is installed at the Argonne Wakefield Accelerator facility (AWA), and is presently being evaluated. The device has a transformer ratio of {approx}12.5:1. When driven by a {approx}50 nC single drive bunch it is expected to obtain {approx}6 MV/m acceleration gradient. Related issues are discussed.

  18. Relativistic Winds from Compact Gamma-Ray Sources: II. Pair Loading and Radiative Acceleration in Gamma-ray Bursts

    E-Print Network [OSTI]

    Christopher Thompson; Piero Madau

    2000-02-21T23:59:59.000Z

    We consider the effects of rapid pair creation by an intense pulse of gamma-rays propagating ahead of a relativistic shock. Side-scattered photons colliding with the main gamma-ray beam amplify the density of scattering charges. The acceleration rate of the pair-loaded medium is calculated, and its limiting bulk Lorentz factor related to the spectrum and compactness of the photon source. One obtains, as a result, a definite prediction for the relative inertia in baryons and pairs. The deceleration of a relativistic shock in the moving medium, and the resulting synchrotron emissivity, are compared with existing calculations for a static medium. The radiative efficiency is increased dramatically by pair loading. When the initial ambient density exceeds a critical value, the scattering depth traversed by the main gamma-ray pulse rises above unity, and the pulse is broadened. These considerations place significant constraints on burst progenitors: a pre-burst mass loss rate exceeding 10^{-5} M_\\odot per year is difficult to reconcile with individual pulses narrower than 10 s, unless the radiative efficiency is low. An anisotropic gamma-ray flux (on an angular scale \\Gamma^{-1} or larger) drives a large velocity shear that greatly increases the energy in the seed magnetic field forward of the propagating shock.

  19. accelerating structure design: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    contract No. DE-AC02-76CH00016. Abstract A common coil design concept for 2-in-1 superconduct- ing Gupta, Ramesh 103 New model for auroral acceleration: O-shaped potential...

  20. Accelerating Structure design and fabrication For KIPT and PAL XFEL

    E-Print Network [OSTI]

    Hou, Mi; Pei, Shilun

    2014-01-01T23:59:59.000Z

    ANL and the National Science Center "Kharkov Institute of Physics Technology" (NSC KIPT, Kharkov, Ukraine) jointly proposed to design and build a 100MeV/100KW linear accelerator which will be used to drive the neutron source subcritical assembly. Now the linac was almost assembled in KIPT by the team from Institute of High Energy Physics (IHEP, Beijing, China). The design and measurement result of the accelerating system of the linac will be described in this paper.

  1. 168 / JOURNAL OF STRUCTURAL ENGINEERING / FEBRUARY 2001 GUST LOADING FACTOR: NEW MODEL

    E-Print Network [OSTI]

    Kareem, Ahsan

    to the mean wind force multiplied by the GLF. Although the traditional GLF method ensures an accurate force multiplied by a GLF. The GLF accounts for the dynamics of wind fluctuations and any load and Ahsan Kareem,2 Member, ASCE ABSTRACT: Wind loads on structures under the buffeting action of wind gusts

  2. A performance-based approach to retrofitting unreinforced masonry structures for seismic loads

    E-Print Network [OSTI]

    Bouchard, Keith M. (Keith Michael)

    2007-01-01T23:59:59.000Z

    The structural inadequacy of existing unreinforced masonry (URM) buildings to resist possible seismic loading is a serious problem in many parts of the United States, including the Northeast and Midwest. The fact that many ...

  3. Commercial application of aluminum honeycomb and foam in load bearing tubular structures

    E-Print Network [OSTI]

    Bartolucci, Stefano, 1976-

    2004-01-01T23:59:59.000Z

    Small dimension engineering tubular structures subjected to a complex load system are designed like hollow circular shells. For minimum weight design, the ratio between the shell radius and the thickness has to be as large ...

  4. Calculation of wakefields in a 17 GHz beam-driven photonic band-gap accelerator structure

    E-Print Network [OSTI]

    Hu, Min

    We present the theoretical analysis and computer simulation of the wakefields in a 17 GHz photonic band-gap (PBG) structure for accelerator applications. Using the commercial code CST Particle Studio, the fundamental ...

  5. H-mode accelerating structures with PMQ focusing for low-beta ion beams

    SciTech Connect (OSTI)

    Kurennoy, Sergey S [Los Alamos National Laboratory; O' Hara, James F [Los Alamos National Laboratory; Olivas, Eric R [Los Alamos National Laboratory; Rybarcyk, Lawrence J [Los Alamos National Laboratory

    2010-01-01T23:59:59.000Z

    We are developing high-efficiency normal-conducting RF accelerating structures based on inter-digital H-mode (IH) cavities and the transverse beam focusing with permanent-magnet quadrupoles (PMQ), for beam velocities in the range of a few percent of the speed of light. Such IH-PMQ accelerating structures following a short RFQ can be used in the front end of ion linacs or in stand-alone applications, e.g. a compact deuteron-beam accelerator up to the energy of several MeV. Results of combined 3-D modeling for a full IH-PMQ accelerator tank - electromagnetic computations, beam-dynamics simulations with high currents, and thermal-stress analysis - are presented. The accelerating field profile in the tank is tuned to provide the best beam propagation using coupled iterations of electromagnetic and beam-dynamics modeling. A cold model of the IH-PMQ tank is being manufactured.

  6. Accelerated Life Structural Benchmark Testing for a Stirling Convertor Heater Head

    SciTech Connect (OSTI)

    Krause, David L. [National Aeronautics and Space Administration, Glenn Research Center, Cleveland, OH 44135 (United States); Kantzos, Pete T. [Ohio Aerospace Institute, NASA Glenn Research Center, Cleveland, OH 44135 (United States)

    2006-01-20T23:59:59.000Z

    For proposed long-duration NASA Space Science missions, the Department of Energy, Lockheed Martin, Infinia Corporation, and NASA Glenn Research Center are developing a high-efficiency, 110-watt Stirling Radioisotope Generator (SRG110). A structurally significant limit state for the SRG110 heater head component is creep deformation induced at high material temperature and low stress level. Conventional investigations of creep behavior adequately rely on experimental results from uniaxial creep specimens, and a wealth of creep data is available for the Inconel 718 material of construction. However, the specified atypical thin heater head material is fine-grained with a heat treatment that limits precipitate growth, and little creep property data for this microstructure is available in the literature. In addition, the geometry and loading conditions apply a multiaxial stress state on the component, far from the conditions of uniaxial testing. For these reasons, an extensive experimental investigation is ongoing to aid in accurately assessing the durability of the SRG110 heater head. This investigation supplements uniaxial creep testing with pneumatic testing of heater head-like pressure vessels at design temperature with stress levels ranging from approximately the design stress to several times that. This paper presents experimental results, post-test microstructural analyses, and conclusions for four higher-stress, accelerated life tests. Analysts are using these results to calibrate deterministic and probabilistic analytical creep models of the SRG110 heater head.

  7. AIRCRAFT PARAMETRIC STRUCTURAL LOAD MONITORING USING GAUSSIAN PROCESS REGRESSION

    E-Print Network [OSTI]

    Boyer, Edmond

    cases. KEYWORDS : Structural Health and Usage Monitoring, Gaussian Process Regression, Fatigue, 1 in the remaining useful life. If the error is too 7th European Workshop on Structural Health Monitoring July 8 manuscript, published in "EWSHM - 7th European Workshop on Structural Health Monitoring (2014)" #12

  8. Evaluation methodology for structures subjected to seismic loading

    E-Print Network [OSTI]

    O'Boyle, Margaret

    1996-01-01T23:59:59.000Z

    } and rearranging Eq. (2. 5): 15 The load distribution applied during the pushover analysis is: au where R i(i) = i-th story shear resistance at the previous computation step, V?= total base shear at the current computation step, and n = current computation... to: $?mv(t) = $?m$, Y, + $?m$z Yz+. . . +P?m)?Y? (2. 14) where $? is the transpose of the n-th mode shape vector. Because of the orthogonality property with respect to mass in which $?m$ = 0 for all n c m, all the terms on the right side of Eq. (2...

  9. Wakefield generation by a relativistic ring beam in a coaxial two channel dielectric loaded structure.

    SciTech Connect (OSTI)

    Liu, W.; Gai, W. (High Energy Physics)

    2009-05-12T23:59:59.000Z

    In this paper, we give a complete analytical solution for wakefields generated by an azimuthally symmetric ring beam propagating in a coaxial two-channel dielectric structure. This wakefield can be used to accelerate a witness beam in the central channel. The ratio of the peak accelerating field in the center channel to the decelerating field in the ring channel (defined as transformer ratio R) is also derived. We find that, by appropriate choice of parameters, R can be much greater than 2, the limiting value for collinear wakefield accelerators.

  10. Measurement of wakefield suppression in a detuned x-band accelerator structure

    SciTech Connect (OSTI)

    Adolphsen, C.; Bane, K.; Higo, T.; Kubo, K.; Miller, R.; Ruth, R.; Thompson, K.; Wang, J.

    1994-08-01T23:59:59.000Z

    Research is underway at SLAC to develop accelerator structures for a next generation linear collider. A full-scale prototype X-band structure has been built in which the dipole mode frequencies were detuned to suppress the long-range transverse wakefield by about two orders of magnitude. To verify that the detuning works as expected, a facility to measure the long-range wakefield, called the Accelerator Structure SETup, or ASSET, was constructed in the SLAC Linear Collider (SLC). This paper presents the results from the measurement of the prototype X-band structure with this facility.

  11. Free electron laser using Rf coupled accelerating and decelerating structures

    DOE Patents [OSTI]

    Brau, Charles A. (Los Alamos, NM); Swenson, Donald A. (Los Alamos, NM); Boyd, Jr., Thomas J. (Los Alamos, NM)

    1984-01-01T23:59:59.000Z

    A free electron laser and free electron laser amplifier using beam transport devices for guiding an electron beam to a wiggler of a free electron laser and returning the electron beam to decelerating cavities disposed adjacent to the accelerating cavities of the free electron laser. Rf energy is generated from the energy depleted electron beam after it emerges from the wiggler by means of the decelerating cavities which are closely coupled to the accelerating cavities, or by means of a second bore within a single set of cavities. Rf energy generated from the decelerated electron beam is used to supplement energy provided by an external source, such as a klystron, to thereby enhance overall efficiency of the system.

  12. Linear particle accelerator with seal structure between electrodes and insulators

    DOE Patents [OSTI]

    Broadhurst, John H. (Golden Valley, MN)

    1989-01-01T23:59:59.000Z

    An electrostatic linear accelerator includes an electrode stack comprised of primary electrodes formed or Kovar and supported by annular glass insulators having the same thermal expansion rate as the electrodes. Each glass insulator is provided with a pair of fused-in Kovar ring inserts which are bonded to the electrodes. Each electrode is designed to define a concavo-convex particle trap so that secondary charged particles generated within the accelerated beam area cannot reach the inner surface of an insulator. Each insulator has a generated inner surface profile which is so configured that the electrical field at this surface contains no significant tangential component. A spark gap trigger assembly is provided, which energizes spark gaps protecting the electrodes affected by over voltage to prevent excessive energy dissipation in the electrode stack.

  13. Wake field in dielectric acceleration structures L. Schachter,1

    E-Print Network [OSTI]

    Byer, Robert L.

    particle accel- erators relies on dielectric slow-wave structures confining a laser field. Conceptually

  14. Damage predictions of aluminum thin-walled structures subjected to explosive loads.

    SciTech Connect (OSTI)

    Saul, W. Venner; Reu, Phillip L.; Gruda, Jeffrey Donald; Haulenbeek, Kimberly K.; Larsen, Marvin Elwood; Phelan, James M.; Stofleth, Jerome H.; Corona, Edmundo; Gwinn, Kenneth West

    2010-11-01T23:59:59.000Z

    Predicting failure of thin-walled structures from explosive loading is a very complex task. The problem can be divided into two parts; the detonation of the explosive to produce the loading on the structure, and secondly the structural response. First, the factors that affect the explosive loading include: size, shape, stand-off, confinement, and chemistry of the explosive. The goal of the first part of the analysis is predicting the pressure on the structure based on these factors. The hydrodynamic code CTH is used to conduct these calculations. Secondly, the response of a structure from the explosive loading is predicted using a detailed finite element model within the explicit analysis code Presto. Material response, to failure, must be established in the analysis to model the failure of this class of structures; validation of this behavior is also required to allow these analyses to be predictive for their intended use. The presentation will detail the validation tests used to support this program. Validation tests using explosively loaded aluminum thin flat plates were used to study all the aspects mentioned above. Experimental measurements of the pressures generated by the explosive and the resulting plate deformations provided data for comparison against analytical predictions. These included pressure-time histories and digital image correlation of the full field plate deflections. The issues studied in the structural analysis were mesh sensitivity, strain based failure metrics, and the coupling methodologies between the blast and structural models. These models have been successfully validated using these tests, thereby increasing confidence of the results obtained in the prediction of failure thresholds of complex structures, including aircraft.

  15. High Transformer ratios in collinear wakefield accelerators.

    SciTech Connect (OSTI)

    Power, J. G.; Conde, M.; Yusof, Z.; Gai, W.; Jing, C.; Kanreykin, A.; Schoessow, P.; High Energy Physics; Euclid Techlabs, LLC

    2008-01-01T23:59:59.000Z

    Based on our previous experiment that successfully demonstrated wakefield transformer ratio enhancement in a 13.625 GHz dielectric-loaded collinear wakefield accelerator using the ramped bunch train technique, we present here a redesigned experimental scheme for even higher enhancement of the efficiency of this accelerator. Design of a collinear wakefield device with a transformer ratio R2, is presented. Using a ramped bunch train (RBT) rather than a single drive bunch, the enhanced transformer ratio (ETR) technique is able to increase the transformer ratio R above the ordinary limit of 2. To match the wavelength of the fundamental mode of the wakefield with the bunch length (sigmaz=2 mm) of the new Argonne wakefield accelerator (AWA) drive gun (where the experiment will be performed), a 26.625 GHz dielectric based accelerating structure is required. This transformer ratio enhancement technique based on our dielectric-loaded waveguide design will result in a compact, high efficiency accelerating structures for future wakefield accelerators.

  16. Effect of the change in the load resistance on the high voltage pulse transformer of the intense electron-beam accelerators

    SciTech Connect (OSTI)

    Cheng Xinbing; Liu Jinliang; Qian Baoliang; Zhang Yu; Zhang Hongbo [College of Photoelectrical Science and Engineering, National University of Defense Technology, Hunan 410073 (China)

    2009-11-15T23:59:59.000Z

    A high voltage pulse transformer (HVPT) is usually used as a charging device for the pulse forming line (PFL) of intense electron-beam accelerators (IEBAs). Insulation of the HVPT is one of the important factors that restrict the development of the HVPT. Until now, considerable effort has been focused on minimizing high field regions to avoid insulation breakdown between windings. Characteristics of the HVPT have been widely discussed to achieve these goals, but the effects of the PFL and load resistance on HVPT are usually neglected. In this paper, a HVPT is used as a charging device for the PFL of an IEBA and the effect of the change in the load resistance on the HVPT of the IEBA is presented. When the load resistance does not match the wave impedance of the PFL, a high-frequency bipolar oscillating voltage will occur, and the amplitude of the oscillating voltage will increase with the decrease in the load resistance. The load resistance approximates to zero and the amplitude of the oscillating voltage is much higher. This makes it easier for surface flashover along the insulation materials to form and decrease the lifetime of the HVPT.

  17. H-mode accelerating structures with permanent-magnet quadrupole beam focusing

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kurennoy, S. S.; Rybarcyk, L. J.; O’Hara, J. F.; Olivas, E. R.; Wangler, T. P.

    2012-09-01T23:59:59.000Z

    We have developed high-efficiency normal-conducting rf accelerating structures by combining H -mode resonator cavities and a transverse beam focusing by permanent-magnet quadrupoles (PMQ), for beam velocities in the range of a few percent of the speed of light. The shunt impedance of interdigital H -mode (IH-PMQ) structures is 10–20 times higher than that of a conventional drift-tube linac, while the transverse size is 4–5 times smaller. Results of the combined 3D modeling—electromagnetic computations, multiparticle beam-dynamics simulations with high currents, and thermal-stress analysis—for an IH-PMQ accelerator tank are presented. The accelerating-field profile in the tank is tuned to provide the best propagation of a 50-mA deuteron beam using coupled iterations of electromagnetic and beam-dynamics modeling. Measurements of a cold model of the IH-PMQ tank show a good agreement with the calculations. Examples of cross-bar H -mode structures with PMQ focusing for higher beam velocities are also presented. H -PMQ accelerating structures following a short radio-frequency quadrupole accelerator can be used both in the front end of ion linacs or in stand-alone applications.

  18. Proposed few-optical cycle laser-driven particle accelerator structure T. Plettner, P. P. Lu, and R. L. Byer

    E-Print Network [OSTI]

    Byer, Robert L.

    Proposed few-optical cycle laser-driven particle accelerator structure T. Plettner, P. P. Lu, and R importance for future laser-driven particle accelerators. Application of such short pulses for laser-driven particle accelerators appears especially appealing from a gradient and an efficiency point of view

  19. Measurement of wakefields generated in accelerator test structures using the SLC

    SciTech Connect (OSTI)

    Adolphsen, C.; Bane, K.; Loew, G.; Ruth, R.; Thompson, K.; Wang, J.

    1992-10-01T23:59:59.000Z

    Research is underway at SLAC to develop accelerator structures for the next generation linear collider. An important feature of the design is a detuning of the dipole modes of the cells to suppress the long-range transverse wakefield by two orders of magnitude. This paper describes a facility, called ASSET, that will be incorporated into the SLAC Linear Collider (SLC) to test the long-range wakefield suppression and also to measure the other components of the wakefields generated in accelerator test structures.

  20. Cavity resonance absorption in ultra-high bandwidth CRT deflection structure by a resistive load

    DOE Patents [OSTI]

    Dunham, M.E.; Hudson, C.L.

    1993-05-11T23:59:59.000Z

    An improved ultra-high bandwidth helical coil deflection structure for a cathode ray tube is described comprising a first metal member having a bore therein, the metal walls of which form a first ground plane; a second metal member coaxially mounted in the bore of the first metal member and forming a second ground plane; a helical deflection coil coaxially mounted within the bore between the two ground planes; and a resistive load disposed in one end of the bore and electrically connected to the first and second ground planes, the resistive load having an impedance substantially equal to the characteristic impedance of the coaxial line formed by the two coaxial ground planes to inhibit cavity resonance in the structure within the ultra-high bandwidth of operation. Preferably, the resistive load comprises a carbon film on a surface of an end plug in one end of the bore.

  1. X-Band Photonic Band-Gap Accelerator Structure Breakdown Experiment

    SciTech Connect (OSTI)

    Marsh, Roark A.; /MIT /MIT /NIFS, Gifu /JAERI, Kyoto /LLNL, Livermore; Shapiro, Michael A.; Temkin, Richard J.; /MIT; Dolgashev, Valery A.; Laurent, Lisa L.; Lewandowski, James R.; Yeremian, A.Dian; Tantawi, Sami G.; /SLAC

    2012-06-11T23:59:59.000Z

    In order to understand the performance of photonic band-gap (PBG) structures under realistic high gradient, high power, high repetition rate operation, a PBG accelerator structure was designed and tested at X band (11.424 GHz). The structure consisted of a single test cell with matching cells before and after the structure. The design followed principles previously established in testing a series of conventional pillbox structures. The PBG structure was tested at an accelerating gradient of 65 MV/m yielding a breakdown rate of two breakdowns per hour at 60 Hz. An accelerating gradient above 110 MV/m was demonstrated at a higher breakdown rate. Significant pulsed heating occurred on the surface of the inner rods of the PBG structure, with a temperature rise of 85 K estimated when operating in 100 ns pulses at a gradient of 100 MV/m and a surface magnetic field of 890 kA/m. A temperature rise of up to 250 K was estimated for some shots. The iris surfaces, the location of peak electric field, surprisingly had no damage, but the inner rods, the location of the peak magnetic fields and a large temperature rise, had significant damage. Breakdown in accelerator structures is generally understood in terms of electric field effects. These PBG structure results highlight the unexpected role of magnetic fields in breakdown. The hypothesis is presented that the moderate level electric field on the inner rods, about 14 MV/m, is enhanced at small tips and projections caused by pulsed heating, leading to breakdown. Future PBG structures should be built to minimize pulsed surface heating and temperature rise.

  2. New Structural Model for Multicomponent Pile Cross Sections under Axial Load

    E-Print Network [OSTI]

    Horvath, John S.

    New Structural Model for Multicomponent Pile Cross Sections under Axial Load John S. Horvath, Ph.D., P.E., M.ASCE1 Abstract: Piles composed of more than one material in their cross section have been used for more than 100 years. Originally this was limited to driven steel shell or pipe piles filled

  3. A METHOD FOR RAPID VULNERABILITY ASSESSMENT OF STRUCTURES LOADED BY OUTSIDE BLASTS

    E-Print Network [OSTI]

    Cizelj, Leon

    military threats to a nuclear power plant in the year 1991 (Stritar et al, 1991). More recent examples cases not been assumed as design basis loads of nuclear power plant buildings and structures. Recent efforts have been recently devoted to the increased security of nuclear power plants (NPP) (see

  4. Loading and Response of Offshore Wind Turbine Support Structures: Prediction with Comparison to Measured Data

    E-Print Network [OSTI]

    Sweetman, Bert

    Loading and Response of Offshore Wind Turbine Support Structures: Prediction with Comparison, offshore wind support platforms differ from oil platforms is several important ways: First, wind platforms is often closer to frequencies at which there is meaningful wave energy. Second, wind farms often include

  5. NONLINEAR FINITE ELEMENT ANALYSIS OF REINFORCED CONCRETE STRUCTURES SUBJECTED TO TRANSIENT THERMAL LOADS

    E-Print Network [OSTI]

    Vecchio, Frank J.

    Abstract ii NONLINEAR FINITE ELEMENT ANALYSIS OF REINFORCED CONCRETE STRUCTURES SUBJECTED nonlinear finite element transient thermal analysis is implemented into program VecTor2©, a nonlinear's response to thermal loads, this research develops and implements a 2D nonlinear finite element transient

  6. CYCLIC PLASTICITY OF A CRACKED STRUCTURE SUBJECTED TO MIXED MODE LOADING

    E-Print Network [OSTI]

    CYCLIC PLASTICITY OF A CRACKED STRUCTURE SUBJECTED TO MIXED MODE LOADING Sylvie Pommier1, a 1 LMT, mixed mode crack propagation, plasticity, crack deflection. Abstract. Cyclic plasticity in the crack tip stresses in the overload's plastic zone. Moreover, if the overload's ratio is large enough, the crack may

  7. Geometric dependence of radio-frequency breakdown in normal conducting accelerating structures

    E-Print Network [OSTI]

    Istituto Nazionale di Fisica Nucleare (INFN)

    Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA 2 High Energy Accelerator Research magnetic field, or alternatively on surface pulsed heating. This is in contrast to the classical view geometries. The structure circuit pa- rameters play a dual role. First, they control the local varia- tion

  8. Alignment tolerance of accelerating structures and corrections for future linear colliders

    SciTech Connect (OSTI)

    Kubo, K.; Adolphsen, C.; Bane, K.L.F.; Raubenheimer, T.O.; Thompson, K.A.

    1995-06-01T23:59:59.000Z

    The alignment tolerance of accelerating structures is estimated by tracking simulations. Both single-bunch and multi-bunch effects are taken into account. Correction schemes for controlling the single and multi-bunch emittance growth in the case of large misalignment are also tested by simulations.

  9. A model for structural response to hydrogen combustion loads in severe accidents

    SciTech Connect (OSTI)

    Breitung, W.; Redlinger, R. [Forschungszentrum Karlsruhe (Germany). Institut fuer Neutronenphysik und Reaktortechnik

    1995-09-01T23:59:59.000Z

    The response of structures to different pressure histories from hydrogen combustion is analyzed using the model of a linear undamped oscillator. The effective static pressures from a slow deflagration-to-detonation transition (DDT) and a stable detonation are calculated as functions of oscillator frequency. The response of components with a low natural frequency, such as the outermost shell in a large dry containment, is governed by the long-term pressure after combustion. Detonation peak pressure and impulse are not important. For structures with low frequencies, fast flames have a damage potential very similar to detonations. For the investigated pressure loads, the normally reflected detonation provides the bounding effective static pressure for oscillators up to 500 Hz. Fully confined DDT events can exceed the detonation load near the transition location for structural frequencies about {approximately}40 Hz.

  10. Load requirements for maintaining structural integrity of Hanford single-shell tanks during waste feed delivery and retrieval activities

    SciTech Connect (OSTI)

    JULYK, L.J.

    1999-09-22T23:59:59.000Z

    This document provides structural load requirements and their basis for maintaining the structural integrity of the Hanford Single-Shell Tanks during waste feed delivery and retrieval activities. The requirements are based on a review of previous requirements and their basis documents as well as load histories with particular emphasis on the proposed lead transfer feed tanks for the privatized vitrification plant.

  11. Shell-Based Support Structures for Nb3Sn Accelerator Quadrupole Magnets

    SciTech Connect (OSTI)

    Ferracin, Paolo

    2008-05-19T23:59:59.000Z

    Shell-based support structures are being fabricated and tested as part of the development of large-aperture Nb{sub 3}Sn superconducting quadrupoles for future upgrades of the LHC Interaction Regions. These structures utilize water pressurized bladders for room-temperature pre-load control, and rely on a pre-tensioned aluminum shell to deliver a substantial part of the coil pre-stress during cool-down. The coil final pre-load is therefore monotonically approached from below, without overstressing the strain-sensitive conductor. This method has been adopted by the US LARP collaboration to test subscale racetrack coils (SQ series), 1 m long cos-theta coils (TQS series), and 4 m long magnets (LRS and LQS series). We present recent progress in the development of shell-based support structures, with a description of the principles of operations and the future plans.

  12. Laser Wakefield Acceleration: Structural and Dynamic Studies. Final Technical Report ER40954

    SciTech Connect (OSTI)

    Downer, Michael C.

    2014-12-19T23:59:59.000Z

    Particle accelerators enable scientists to study the fundamental structure of the universe, but have become the largest and most expensive of scientific instruments. In this project, we advanced the science and technology of laser-plasma accelerators, which are thousands of times smaller and less expensive than their conventional counterparts. In a laser-plasma accelerator, a powerful laser pulse exerts light pressure on an ionized gas, or plasma, thereby driving an electron density wave, which resembles the wake behind a boat. Electrostatic fields within this plasma wake reach tens of billions of volts per meter, fields far stronger than ordinary non-plasma matter (such as the matter that a conventional accelerator is made of) can withstand. Under the right conditions, stray electrons from the surrounding plasma become trapped within these “wake-fields”, surf them, and acquire energy much faster than is possible in a conventional accelerator. Laser-plasma accelerators thus might herald a new generation of compact, low-cost accelerators for future particle physics, x-ray and medical research. In this project, we made two major advances in the science of laser-plasma accelerators. The first of these was to accelerate electrons beyond 1 gigaelectronvolt (1 GeV) for the first time. In experimental results reported in Nature Communications in 2013, about 1 billion electrons were captured from a tenuous plasma (about 1/100 of atmosphere density) and accelerated to 2 GeV within about one inch, while maintaining less than 5% energy spread, and spreading out less than ½ milliradian (i.e. ½ millimeter per meter of travel). Low energy spread and high beam collimation are important for applications of accelerators as coherent x-ray sources or particle colliders. This advance was made possible by exploiting unique properties of the Texas Petawatt Laser, a powerful laser at the University of Texas at Austin that produces pulses of 150 femtoseconds (1 femtosecond is 10-15 seconds) in duration and 150 Joules in energy (equivalent to the muzzle energy of a small pistol bullet). This duration was well matched to the natural electron density oscillation period of plasma of 1/100 atmospheric density, enabling efficient excitation of a plasma wake, while this energy was sufficient to drive a high-amplitude wake of the right shape to produce an energetic, collimated electron beam. Continuing research is aimed at increasing electron energy even further, increasing the number of electrons captured and accelerated, and developing applications of the compact, multi-GeV accelerator as a coherent, hard x-ray source for materials science, biomedical imaging and homeland security applications. The second major advance under this project was to develop new methods of visualizing the laser-driven plasma wake structures that underlie laser-plasma accelerators. Visualizing these structures is essential to understanding, optimizing and scaling laser-plasma accelerators. Yet prior to work under this project, computer simulations based on estimated initial conditions were the sole source of detailed knowledge of the complex, evolving internal structure of laser-driven plasma wakes. In this project we developed and demonstrated a suite of optical visualization methods based on well-known methods such as holography, streak cameras, and coherence tomography, but adapted to the ultrafast, light-speed, microscopic world of laser-driven plasma wakes. Our methods output images of laser-driven plasma structures in a single laser shot. We first reported snapshots of low-amplitude laser wakes in Nature Physics in 2006. We subsequently reported images of high-amplitude laser-driven plasma “bubbles”, which are important for producing electron beams with low energy spread, in Physical Review Letters in 2010. More recently, we have figured out how to image laser-driven structures that change shape while propagating in a single laser shot. The latter techniques, which use the methods of computerized tomography, were demonstrated on test objects – e.g. laser-d

  13. accelerating technology transfer: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Effect of Accelerated Ash Loading Youngquist and Ke Nguyen University of Tennessee Knoxville, TN 37996 An accelerated ash loading protocol using a single-cylinder diesel engine...

  14. Turbulence descriptors for scaling fatigue loading spectra of wind turbine structural components

    SciTech Connect (OSTI)

    Kelley, N.D.

    1994-07-01T23:59:59.000Z

    The challenge for the designer in developing a new wind turbine is to incorporate sufficient strength in its components to safely achieve a 20- or 30-year service life. To accomplish this, the designer must understand the load and stress distributions (in a statistical sense at least) that the turbine is likely to encounter during its operating life. Sources of loads found in the normal operating environment include start/stop cycles, emergency shutdowns, the turbulence environment associated with the specific site and turbine location, and extreme or ``rare`` events that can challenge the turbine short-term survivability. Extreme events can result from an operational problem (e.g., controller failure) or violent atmospheric phenomena (tornadic circulations, strong gust fronts). For the majority of the operating time, however, the character of the turbulent inflow is the dominant source of the alternating stress distributions experienced by the structural components. Methods of characterizing or scaling the severity of the loading spectra (or the rate of fatigue damage accumulation) must be applicable to a wide range of turbulent inflow environments -- from solitary isolation to the complex flows associated with multi-row wind farms. The metrics chosen must be related to the properties of the turbulent inflow and independent of the nature of local terrain features.

  15. Altered structural development and accelerated succession from intermediate-scale wind disturbance in Quercus stands on the

    E-Print Network [OSTI]

    Hart, Justin

    . Logistic regression revealed an increasing probability of mortality during wind disturbance with increasingAltered structural development and accelerated succession from intermediate-scale wind disturbance Structure Succession Wind a b s t r a c t Natural disturbances play important roles in shaping the structure

  16. Multiorbit induction accelerators

    SciTech Connect (OSTI)

    Zvontsov, A.A.; Kas'yanov, V.A.; Chakhlov, V.L.

    1985-09-01T23:59:59.000Z

    Large numbers of particles accelerated per cycle are made possible by accelerating simultaneously in several equilibrium orbits in a single betatron structure. (AIP)

  17. Offshore structures can be subjected to millions of variable amplitude load cycles during their service life which is the primary cause of structural deterioration. Such

    E-Print Network [OSTI]

    Boyer, Edmond

    ABSTRACT Offshore structures can be subjected to millions of variable amplitude load cycles during and methods coupled with a growing appetite to exploit the bountiful offshore energy resources has lead to the installation of more and more offshore structures and at greater depths. These structures can experience

  18. Archival Journals: 1. "Ship Bottom Structure under Uniform Lateral and Inplane Loads," Schiff und Hafen, Heft 5, May

    E-Print Network [OSTI]

    Mofrad, Mohammad R. K.

    Archival Journals: 1. "Ship Bottom Structure under Uniform Lateral and Inplane Loads," Schiff und Research, Vol. 16, No. 2, June 1972, pp. 113-123 (also M.I.T. Report No. 70-15, Sept. 1970). 4. "Post-buckling

  19. Inverse Load Calculation of Wind Turbine Support Structures - A Numerical Verification Using the Comprehensive Simulation Code FAST: Preprint (Revised)

    SciTech Connect (OSTI)

    Pahn, T.; Jonkman, J.; Rolges, R.; Robertson, A.

    2012-11-01T23:59:59.000Z

    Physically measuring the dynamic responses of wind turbine support structures enables the calculation of the applied loads using an inverse procedure. In this process, inverse means deriving the inputs/forces from the outputs/responses. This paper presents results of a numerical verification of such an inverse load calculation. For this verification, the comprehensive simulation code FAST is used. FAST accounts for the coupled dynamics of wind inflow, aerodynamics, elasticity and turbine controls. Simulations are run using a 5-MW onshore wind turbine model with a tubular tower. Both the applied loads due to the instantaneous wind field and the resulting system responses are known from the simulations. Using the system responses as inputs to the inverse calculation, the applied loads are calculated, which in this case are the rotor thrust forces. These forces are compared to the rotor thrust forces known from the FAST simulations. The results of these comparisons are presented to assess the accuracy of the inverse calculation. To study the influences of turbine controls, load cases in normal operation between cut-in and rated wind speed, near rated wind speed and between rated and cut-out wind speed are chosen. The presented study shows that the inverse load calculation is capable of computing very good estimates of the rotor thrust. The accuracy of the inverse calculation does not depend on the control activity of the wind turbine.

  20. Published in Proceedings of the XL2003 (Response of Structures to Extreme Loading) Conference, Toronto, August 2003. EFFICIENT MODELS FOR WIND TURBINE EXTREME LOADS

    E-Print Network [OSTI]

    Manuel, Lance

    , Toronto, August 2003. EFFICIENT MODELS FOR WIND TURBINE EXTREME LOADS USING INVERSE RELIABILITY K, USA ABSTRACT The reliability of wind turbines against extreme loads is the focus of this study loads for a 600kW three-bladed horizontal-axis wind turbine. Only operating loads ­ here, flapwise (out

  1. Testing and analysis of structural steel columns subjected to blast loads

    E-Print Network [OSTI]

    Stewart, Lauren K.

    2010-01-01T23:59:59.000Z

    Blast Simulator Testing of Steel Columns and Components. ”Testing of Structural Steel Columns. ” 8 th Internationaland Analysis of Structural Steel Columns Subjected to Blast

  2. A New Cavity Design For Medium Beta Acceleration

    SciTech Connect (OSTI)

    He, Feisi [Peking University, Beijing (China); Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Wang, Haipeng [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Rimmer, Robert A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    2014-02-01T23:59:59.000Z

    Heavy duty or cw, superconducting proton and heavy ion accelerators are being proposed and constructed worldwide. The total length of the machine is one of the main drivers in terms of cost. Thus hwr and spoke cavities at medium beta are usually optimized to achieve low surface field and high gradient. A novel accelerating structure at beta=0.5 evolved from spoke cavity is proposed, with lower surface fields but slightly higher heat load. It would be an interesting option for pulsed and cw accelerators with beam energy of more than 200mev/u.

  3. Load test of the 283W Clearwell Roof Deck and Support Structure

    SciTech Connect (OSTI)

    McCoy, R.M.

    1994-09-12T23:59:59.000Z

    The 283W Clearwell roof area was load tested according to the approved load-test procedure, WHC-SD-GN-TP-30015, Revision 0, as modified below. The 283W Clearwell is located in the 200 West Area of the Hanford Site and has the following characteristics: Roof deck - concrete slab supported by columns and walls; Roof membrane - tar and gravel; Roof slope - flat (< 10 deg); and Roof elevation - approximately 6 in. above ground level. The 283W Clearwell was visited in April 1993 for a visual inspection, but could not be inspected because of the confined space requirements. It was revisited in February 1994 for the purpose of writing this test report. Because the roof could not be inspected, a test was determined to be the best way to qualify the roof for personnel access.

  4. Calculational analysis of structural activation induced by 20-100 MeV proton beam loss in high-power linear accelerators

    E-Print Network [OSTI]

    Lee, Stacey Kirsten

    1994-01-01T23:59:59.000Z

    fulfillment of the requirements for the degree of MASTER OF SCIENCE August 1994 Major Subject: Nuclear Engineering CALCULATIONAL ANALYSIS OF STRUCTURAL ACTIVATION INDUCED BY 20-100 MEV PROTON BEAM LOSS IN HIGH-POWER LINEAR ACCELERATORS A Thesis...) Carl A. Beard (Member) / John . Poston (Head of Department) August 1994 Major Subject: Nuclear Engineering ABSTRACT Calculational Analysis of Structural Activation Induced by 20-100 MeV Proton Beam Loss in High-Power Linear Accelerators. (August...

  5. Load test of the 277W Building high bay roof deck and support structure

    SciTech Connect (OSTI)

    McCoy, R.M.

    1994-12-02T23:59:59.000Z

    The 277W Building high bay roof area was load tested according to the approved load-test procedure, WHC-SD-GN-TP-30015, Revision 1. The 277W Building is located in the 200 West Area of the Hanford Site and has the following characteristics: roof deck -- wood decking supported by 4 x 14 timber purlins; roof membrane -- tar and gravel; roof slope -- flat (<10 deg); and roof elevation -- maximum height of about 63 ft. The 227W Building was visited in March 1994 for a visual inspection. During this inspection, cracked areas were visible in the decking, but it was not possible to determine whether these cracks extended completely through the decking, which is 2-in. thick. The building was revisited in March 1994 for the purpose of writing this test report. Because the roof requires personnel access, a test was determined to be the best way to qualify the roof. The conclusions are that the roof has been qualified for 500-lb total roof load and that the ``No Roof Access`` signs can be changed to ``Roof Access Restricted`` signs.

  6. Eect of sludge-processing mode, soil texture and soil pH on metal mobility in undisturbed soil columns under accelerated loading

    E-Print Network [OSTI]

    Walter, M.Todd

    Eect of sludge-processing mode, soil texture and soil pH on metal mobility in undisturbed soil 8 September 1999 Abstract The eect of sludge processing (digested dewatered, pelletized, alkaline (Lamellic Hapludalf), at initial pH levels of 5 and 7. Sludges were applied during four accelerated cropping

  7. Crash behavior of three dimensional thin-walled structures under combined loading

    E-Print Network [OSTI]

    Kim, Heung-Soo, 1971-

    2001-01-01T23:59:59.000Z

    For the weight efficient and crashworthy design of the structural body of a transportation system, a thorough understanding of crushing behavior of thin-walled structural members such as spot-welded sheet metal beams or ...

  8. Field Profile and Loading Measurements on Higher Order Modes in a Two Cell 500 MHz Superconducting Structure

    E-Print Network [OSTI]

    Barry, W.

    2011-01-01T23:59:59.000Z

    in the Proceedings Field Profile and Loading Measurements onNo. N00014-91-4152. Field Profile and Loading Measurementspart of this study, field profile and loading measurements

  9. Design of an electromagnetic accelerator for turbulent hydrodynamic mix studies

    SciTech Connect (OSTI)

    Susoeff, A.R.; Hawke, R.S.; Morrison, J.J.; Dimonte, G.; Remington, B.A.

    1993-12-08T23:59:59.000Z

    An electromagnetic accelerator in the form of a linear electric motor (LEM) has been designed to achieve controlled acceleration profiles of a carriage containing hydrodynamically unstable fluids for the investigation of the development of turbulent mix. The Rayleigh- Taylor instability is investigated by accelerating two dissimilar density fluids using the LEM to achieve a wide variety of acceleration and deceleration profiles. The acceleration profiles are achieved by independent control of rail and augmentation currents. A variety of acceleration-time profiles are possible including: (1) constant, (2) impulsive and (3) shaped. The LEM and support structure are a robust design in order to withstand high loads with deflections and to mitigate operational vibration. Vibration of the carriage during acceleration could create artifacts in the data which would interfere with the intended study of the Rayleigh-Taylor instability. The design allows clear access for diagnostic techniques such as laser induced fluorescence radiography, shadowgraphs and particle imaging velocimetry. Electromagnetic modeling codes were used to optimize the rail and augmentation coil positions within the support structure framework. Results of contemporary studies for non-arcing sliding contact of solid armatures are used for the design of the driving armature and the dynamic electromagnetic braking system. A 0. 6MJ electrolytic capacitor bank is used for energy storage to drive the LEM. This report will discuss a LEM design which will accelerate masses of up to 3kg to a maximum of about 3000g{sub o}, where g{sub o} is accelerated due to gravity.

  10. Development of load and resistance factor design for FRP strengthening of reinforced concrete structures

    E-Print Network [OSTI]

    Atadero, Rebecca Anne

    2006-01-01T23:59:59.000Z

    Design for FRP Strengthening of Reinforced Concrete. In 7 thFRP) Reinforcement for Concrete Structure; Shield, C.K. ,G.C. Fatigue Performance of Concrete Beams Strengthened with

  11. REVIEW OF PRACTICE FOR DEEPLY EMBEDDED/BURIED NPP STRUCTURES SUBJECT TO SEISMIC LOADINGS.

    SciTech Connect (OSTI)

    XU,J.HOFMAYER,C.MILLER,C.GRAVES,H.

    2004-03-24T23:59:59.000Z

    Motivated by many design considerations, several conceptual designs for advanced reactors have proposed that the entire reactor building and a significant portion of the steam generator building will be either partially or completely embedded below grade. For the analysis of seismic events, the soil-structure interaction (SSI) effect and passive earth pressure for these types of deeply embedded structures will have a significant influence on the predicted seismic response. Sponsored by the US Nuclear Regulatory Commission (NRC), Brookhaven National Laboratory (BNL) is carrying out a research program to assess the significance of these proposed design features for advanced reactors, and to evaluate the existing analytical methods to determine their applicability and adequacy in capturing the seismic behavior of the proposed designs. This paper summarizes a literature review performed by BNL to determine the state of knowledge and practice for seismic analyses of deeply embedded and/or buried (DEB) nuclear containment type structures. Included in the paper is BNL's review of the open literature of existing standards, tests, and practices that have been used in the design and analysis of DEB structures. The paper also provides BNL's evaluation of available codes and guidelines with respect to seismic design practice of DEB structures. Based on BNL's review, a discussion is provided to highlight the applicability of the existing technologies for seismic analyses of DEB structures and to identify gaps that may exist in knowledge and potential issues that may require better understanding and further research.

  12. The X-ray Jet in Centaurus A: Clues on the Jet Structure and Particle Acceleration

    E-Print Network [OSTI]

    Jun Kataoka; Lukasz Stawarz; Felix Aharonian; Fumio Takahara; Michal Ostrowski; Philip G. Edwards

    2005-12-10T23:59:59.000Z

    We report detailed studies of the X-ray emission from the kpc scale jet in the nearest active galaxy, Cen A. 41 compact sources were found within the jet, 13 of which were newly identified. We construct the luminosity function for the detected jet-knots and argue that the remaining emission is most likely to be truly diffuse, rather than resulting from the pile-up of unresolved faint knots. The transverse jet profile reveals that the extended emission has the intensity peak at the jet boundaries. We note that limb-brightened jet morphologies have been observed previously at radio frequencies in some jet sources, but never so clearly at higher photon energies. Our result therefore supports a stratified jet model, consisting of a relativistic outflow including a boundary layer with a velocity shear. In addition, we found that the X-ray spectrum of the diffuse component is almost uniform across and along the jet. We discuss this spectral behavior within a framework of shock and stochastic particle acceleration processes. We note some evidence for a possible spectral hardening at the outer sheath of the jet. Due to the limited photon statistics of the present data, further deep observations of Cen A are required to determine the reality of this finding, however we note that the existence of the hard X-ray features at outer jet boundaries would provide an important challenge to theories for the evolution of ultra-relativistic particles within the jets.

  13. Computational structure-based methods to anticipate HIV drug resistance evolution and accelerate inhibitor discovery

    E-Print Network [OSTI]

    Chang, Max W.

    2008-01-01T23:59:59.000Z

    energy results from large-scale virtual screening identi?es representative wild-wild-type structure, speci?c amino acid substitutions are modeled, followed by energywild?type HIV?1 mutant HIV?2 Ligand Protease Figure 6.2: Speci?c energy

  14. Structure of Velocity Distribution of Sheath-Accelerated Secondary Electrons in Asymmetric RF-DC Discharge

    E-Print Network [OSTI]

    Khrabrov, Alexander V; Ventzek, Peter L G; Ranjan, Alok; Chen, Lee

    2015-01-01T23:59:59.000Z

    The ballistic population is thought to be responsible for alleviating the electron shading effect and the notching of the photoresist layer. We have performed test-particle simulations where the features in the EVDF of electrons impacting the RF electrode are fully resolved at all energies. An analytic model has been developed to predict existence of peaked and step-like structures in the EVDF.

  15. Accelerators and the Accelerator Community

    E-Print Network [OSTI]

    Malamud, Ernest

    2009-01-01T23:59:59.000Z

    for a PhD in accelerator physics was by E.O. Lawrence.of Beams) organizes accelerator physics sessions at APSstudents specializing in accelerator physics are not being “

  16. Base reinforcement results from the addition of a geosynthetic at the bottom or within a base course to increase the structural or load-carrying capacity of a pavement system. While there is clear evidence that geosynthetic

    E-Print Network [OSTI]

    Zornberg, Jorge G.

    course to increase the structural or load-carrying capacity of a pavement system. While there is clear evidence that geosynthetic reinforcements can lead to improved pavement performance, the identification, pavement structures deteriorate under the combined effects of traffic loading and environmental conditions

  17. Accelerating Atomic Orbital-based Electronic Structure Calculation via Pole Expansion plus Selected Inversion

    E-Print Network [OSTI]

    Lin, Lin; Yang, Chao; He, Lixin

    2012-01-01T23:59:59.000Z

    We describe how to apply the recently developed pole expansion plus selected inversion (PEpSI) technique to Kohn-Sham density function theory (DFT) electronic structure calculations that are based on atomic orbital discretization. We give analytic expressions for evaluating charge density, total energy, Helmholtz free energy and atomic forces without using the eigenvalues and eigenvectors of the Kohn-Sham Hamiltonian. We also show how to update the chemical potential without using Kohn-Sham eigenvalues. The advantage of using PEpSI is that it has a much lower computational complexity than that associated with the matrix diagonalization procedure. We demonstrate the performance gain by comparing the timing of PEpSI with that of diagonalization on insulating and metallic nanotubes. For these quasi-1D systems, the complexity of PEpSI is linear with respect to the number of atoms. This linear scaling can be observed in our computational experiments when the number of atoms in a nanotube is larger than a few hundr...

  18. Adaptive control for accelerators

    DOE Patents [OSTI]

    Eaton, Lawrie E. (Los Alamos, NM); Jachim, Stephen P. (Los Alamos, NM); Natter, Eckard F. (Santa Fe, NM)

    1991-01-01T23:59:59.000Z

    An adaptive feedforward control loop is provided to stabilize accelerator beam loading of the radio frequency field in an accelerator cavity during successive pulses of the beam into the cavity. A digital signal processor enables an adaptive algorithm to generate a feedforward error correcting signal functionally determined by the feedback error obtained by a beam pulse loading the cavity after the previous correcting signal was applied to the cavity. Each cavity feedforward correcting signal is successively stored in the digital processor and modified by the feedback error resulting from its application to generate the next feedforward error correcting signal. A feedforward error correcting signal is generated by the digital processor in advance of the beam pulse to enable a composite correcting signal and the beam pulse to arrive concurrently at the cavity.

  19. Tribometer with programmable motion and load to investigate the influence of molecular structure on wear of orthopaedic polyethylene 

    E-Print Network [OSTI]

    Kilgour, Alastair Scott

    2010-01-01T23:59:59.000Z

    ; Polytetrafluroethylene, Polyacetal, and UHMWPE were subjected to linear-reciprocating (LR) and novel elliptical motion paths under a Paul-type load profile. All three polymers showed higher wear factors under elliptical motion, by up to 2 orders of magnitude, agreeing...

  20. High Gradient Two-Beam Electron Accelerator

    SciTech Connect (OSTI)

    Jiang, Y. [Beam Physics Laboratory, Yale University, 272 Whitney Ave., New Haven, CT 06511 (United States); Kazakov, S. Yu. [Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States); Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Kuzikov, S. V. [Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States); Institute of Applied Physics, Nizhny Novgorod, 603600 (Russian Federation); Hirshfield, J. L. [Beam Physics Laboratory, Yale University, 272 Whitney Ave., New Haven, CT 06511 (United States); Omega-P, Inc., 258 Bradley St., New Haven, CT 06510 (United States)

    2010-11-04T23:59:59.000Z

    A high-gradient two-beam electron accelerator structure using detuned cavities is described. A self-consistent theory based on a circuit model is presented to calculate idealized acceleration gradient, transformer ratio, and efficiency for energy transfer from the drive beam to the accelerated beam. Experimental efforts are being carried out to demonstrate this acceleration concept.

  1. High-Power Rf Load

    DOE Patents [OSTI]

    Tantawi, Sami G. (San Mateo, CA); Vlieks, Arnold E. (Livermore, CA)

    1998-09-01T23:59:59.000Z

    A compact high-power RF load comprises a series of very low Q resonators, or chokes [16], in a circular waveguide [10]. The sequence of chokes absorb the RF power gradually in a short distance while keeping the bandwidth relatively wide. A polarizer [12] at the input end of the load is provided to convert incoming TE.sub.10 mode signals to circularly polarized TE.sub.11 mode signals. Because the load operates in the circularly polarized mode, the energy is uniformly and efficiently absorbed and the load is more compact than a rectangular load. Using these techniques, a load having a bandwidth of 500 MHz can be produced with an average power dissipation level of 1.5 kW at X-band, and a peak power dissipation of 100 MW. The load can be made from common lossy materials, such as stainless steel, and is less than 15 cm in length. These techniques can also produce loads for use as an alternative to ordinary waveguide loads in small and medium RF accelerators, in radar systems, and in other microwave applications. The design is easily scalable to other RF frequencies and adaptable to the use of other lossy materials.

  2. Used Nuclear Fuel Loading and Structural Performance Under Normal Conditions of Transport - Modeling, Simulation and Experimental Integration RD&D Plan

    SciTech Connect (OSTI)

    Adkins, Harold E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-04-01T23:59:59.000Z

    Under current U.S. Nuclear Regulatory Commission regulation, it is not sufficient for used nuclear fuel (UNF) to simply maintain its integrity during the storage period, it must maintain its integrity in such a way that it can withstand the physical forces of handling and transportation associated with restaging the fuel and moving it to treatment or recycling facilities, or a geologic repository. Hence it is necessary to understand the performance characteristics of aged UNF cladding and ancillary components under loadings stemming from transport initiatives. Researchers would like to demonstrate that enough information, including experimental support and modeling and simulation capabilities, exists to establish a preliminary determination of UNF structural performance under normal conditions of transport (NCT). This research, development and demonstration (RD&D) plan describes a methodology, including development and use of analytical models, to evaluate loading and associated mechanical responses of UNF rods and key structural components. This methodology will be used to provide a preliminary assessment of the performance characteristics of UNF cladding and ancillary components under rail-related NCT loading. The methodology couples modeling and simulation and experimental efforts currently under way within the Used Fuel Disposition Campaign (UFDC). The methodology will involve limited uncertainty quantification in the form of sensitivity evaluations focused around available fuel and ancillary fuel structure properties exclusively. The work includes collecting information via literature review, soliciting input/guidance from subject matter experts, performing computational analyses, planning experimental measurement and possible execution (depending on timing), and preparing a variety of supporting documents that will feed into and provide the basis for future initiatives. The methodology demonstration will focus on structural performance evaluation of Westinghouse WE 17×17 pressurized water reactor fuel assemblies with a discharge burnup range of 30-58 GWd/MTU (assembly average), loaded in a representative high-capacity (?32 fuel rod assemblies) transportation package. Evaluations will be performed for representative normal conditions of rail transport involving a rail conveyance capable of meeting the Association of American Railroads (AAR) S-2043 specification. UNF modeling is anticipated to be defined to the pellet-cladding level and take in to account influences associated with spacer grids, intermediate fluid mixers, and control components. The influence of common degradation issues such as ductile-to-brittle-transition will also be accounted for. All model development and analysis will be performed with commercially available software packages exclusively. Inputs and analyses will be completely documented, all supporting information will be traceable, and bases will be defendable so as to be most useful to the U.S. Department of Energy community and mission. The expected completion date is the end of fiscal year (FY) 2013.

  3. Pressure loadings of Soviet-designed VVER (Water-Cooled, Water-Moderated Energy Reactor) reactor release mitigation structures from large-break LOCAs

    SciTech Connect (OSTI)

    Sienicki, J.J.; Horak, W.C. (Argonne National Lab., IL (USA); Brookhaven National Lab., Upton, NY (USA))

    1989-01-01T23:59:59.000Z

    Analyses have been carried out of the pressurization of the accident release mitigation structures of Soviet-designed VVER (Water-Cooled, Water-Moderated Energy Reactor) pressurized water reactors following large-break loss-of-coolant accidents. Specific VVER systems for which calculations were performed are the VVER-440 model V230, VVER-440 model V213, and VVER-1000 model V320. Descriptions of the designs of these and other VVER models are contained in the report DOE/NE-0084. The principal objective of the current analyses is to calculate the time dependent pressure loadings inside the accident localization or containment structures immediately following the double-ended guillotine rupture of a primary coolant pipe. In addition, the pressures are compared with the results of calculations of the response of the structures to overpressure. Primary coolant system thermal hydraulic conditions and the fluid conditions at the break location were calculated with the RETRAN-02 Mod2 computer code (Agee, 1984). Pressures and temperatures inside the building accident release mitigation structures were obtained from the PACER (Pressurization Accompanying Coolant Escape from Ruptures) multicompartment containment analysis code developed at Argonne National Laboratory. The analyses were carried out using best estimate models and conditions rather than conservative, bounding-type assumptions. In particular, condensation upon structure and equipment was calculated using correlations based upon analyses of the HDR, Marviken, and Battelle Frankfurt containment loading experiments. The intercompartment flow rates incorporate an effective discharge coefficient and liquid droplet carryover fraction given by expressions of Schwan determined from analyses of the Battelle Frankfurt and Marviken tests. 5 refs., 4 figs.

  4. Fluid acceleration effects on suspended sediment transport in the J. A. Puleo, K. T. Holland, and N. G. Plant

    E-Print Network [OSTI]

    Slinn, Donald

    in suspended load followed the anomalies in acceleration in a way that was not apparent from the nearly

  5. Petawatt pulsed-power accelerator

    DOE Patents [OSTI]

    Stygar, William A. (Albuquerque, NM); Cuneo, Michael E. (Albuquerque, NM); Headley, Daniel I. (Albuquerque, NM); Ives, Harry C. (Albuquerque, NM); Ives, legal representative; Berry Cottrell (Albuquerque, NM); Leeper, Ramon J. (Albuquerque, NM); Mazarakis, Michael G. (Albuquerque, NM); Olson, Craig L. (Albuquerque, NM); Porter, John L. (Sandia Park, NM); Wagoner; Tim C. (Albuquerque, NM)

    2010-03-16T23:59:59.000Z

    A petawatt pulsed-power accelerator can be driven by various types of electrical-pulse generators, including conventional Marx generators and linear-transformer drivers. The pulsed-power accelerator can be configured to drive an electrical load from one- or two-sides. Various types of loads can be driven; for example, the accelerator can be used to drive a high-current z-pinch load. When driven by slow-pulse generators (e.g., conventional Marx generators), the accelerator comprises an oil section comprising at least one pulse-generator level having a plurality of pulse generators; a water section comprising a pulse-forming circuit for each pulse generator and a level of monolithic triplate radial-transmission-line impedance transformers, that have variable impedance profiles, for each pulse-generator level; and a vacuum section comprising triplate magnetically insulated transmission lines that feed an electrical load. When driven by LTD generators or other fast-pulse generators, the need for the pulse-forming circuits in the water section can be eliminated.

  6. Stress Analysis and Structural Optimization of a Three-Layer Composite Cladding Tube Under Thermo-Mechanical Loads

    SciTech Connect (OSTI)

    S.-S. Zhou; X.-L. Gao; G. W. Griffith

    2012-07-01T23:59:59.000Z

    A general solution for the stress and strain fields in a three-layer composite tube subjected to internal and external pressures and temperature changes is first derived using thermo-elasticity. The material in each layer is treated as orthotropic, and the composite tube is regarded to be in a generalized plane strain state. A three-layer ZRY4-SiCf/SiCSiC composite cladding tube under a combined pressure and thermal loading is then analyzed and optimized by applying the general solution. The effects of temperature changes, applied pressures, and layer thickness on the mechanical behavior of the tube are quantitatively studied. The von Mises failure criterion for isotropic materials and the Tsai-Wu's failure theory for composites are used, respectively, to predict the failure behavior of the monolithic ZRY4 (i.e., Zircaloy-4) inner layer and SiC outer layer and the composite SiCf/SiC core layer of the three-layer tube. The numerical results reveal that the maximum radial and circumferential stresses in each layer always occur on the bonding surfaces. By adjusting the thickness of each layer, the effective stress in the three-layer cladding tube under the prescribed thermal-mechanical loading can be changed, thereby making it possible to optimally design the cladding tube.

  7. Dielectric Wakefield Accelerator to drive the future FEL Light Source.

    SciTech Connect (OSTI)

    Jing, C.; Power, J.; Zholents, A. (Accelerator Systems Division (APS)); ( HEP); (LLC)

    2011-04-20T23:59:59.000Z

    X-ray free-electron lasers (FELs) are expensive instruments and a large part of the cost of the entire facility is driven by the accelerator. Using a high-energy gain dielectric wake-field accelerator (DWA) instead of the conventional accelerator may provide a significant cost saving and reduction of the facility size. In this article, we investigate using a collinear dielectric wakefield accelerator to provide a high repetition rate, high current, high energy beam to drive a future FEL x-ray light source. As an initial case study, a {approx}100 MV/m loaded gradient, 850 GHz quartz dielectric based 2-stage, wakefield accelerator is proposed to generate a main electron beam of 8 GeV, 50 pC/bunch, {approx}1.2 kA of peak current, 10 x 10 kHz (10 beamlines) in just 100 meters with the fill factor and beam loading considered. This scheme provides 10 parallel main beams with one 100 kHz drive beam. A drive-to-main beam efficiency {approx}38.5% can be achieved with an advanced transformer ratio enhancement technique. rf power dissipation in the structure is only 5 W/cm{sup 2} in the high repetition rate, high gradient operation mode, which is in the range of advanced water cooling capability. Details of study presented in the article include the overall layout, the transform ratio enhancement scheme used to increase the drive to main beam efficiency, main wakefield linac design, cooling of the structure, etc.

  8. Fusion of remote vision and on-board acceleration data for the vibration estimation of large space structures

    E-Print Network [OSTI]

    Bilton, Amy M. (Amy Marlou)

    2006-01-01T23:59:59.000Z

    Future space structures such as solar power stations and telescopes are expected to be very large. These structures will require on-orbit construction. Due to the risks and costs of human extravehicular work, teams of ...

  9. Composite Load Model Evaluation

    SciTech Connect (OSTI)

    Lu, Ning; Qiao, Hong (Amy)

    2007-09-30T23:59:59.000Z

    The WECC load modeling task force has dedicated its effort in the past few years to develop a composite load model that can represent behaviors of different end-user components. The modeling structure of the composite load model is recommended by the WECC load modeling task force. GE Energy has implemented this composite load model with a new function CMPLDW in its power system simulation software package, PSLF. For the last several years, Bonneville Power Administration (BPA) has taken the lead and collaborated with GE Energy to develop the new composite load model. Pacific Northwest National Laboratory (PNNL) and BPA joint force and conducted the evaluation of the CMPLDW and test its parameter settings to make sure that: • the model initializes properly, • all the parameter settings are functioning, and • the simulation results are as expected. The PNNL effort focused on testing the CMPLDW in a 4-bus system. An exhaustive testing on each parameter setting has been performed to guarantee each setting works. This report is a summary of the PNNL testing results and conclusions.

  10. Accelerate Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Accelerate Energy Productivity 2030 Over the next year, the U.S. Department of Energy, the Council on Competitiveness and the Alliance to Save Energy will join forces to undertake...

  11. APT accelerator technology

    SciTech Connect (OSTI)

    Schneider, J.D.

    1996-09-01T23:59:59.000Z

    Proposed accelerator production of tritium (APT) project requires an accelerator providing a cw proton beam of 100 mA at 1300 MeV. Since most of the technical risk of a high-current cw (continuous-wave, 100% DF) accelerator resides in the low-energy section, Los Alamos is building a 20 MeV duplicate of the accelerator front end to confirm design codes, beam performance, and demonstrate operaional reliability. We report on design details of this low-energy demonstration accelerator (LEDA) and discuss the integrated design of the full accelerator for the APT plant. LEDA`s proton injector is under test and has produced more than 130 mA at 75 keV. Fabrication is proceeding on a 6.7-KeV, 8-m long RFQ, and detailed design is underway on coupled-cavity drift-tube linac (CCDTL) structures. Detailed design and technology experiments are underway on medium-beta superconducting cavities to assess feasibility of replacing the conventional (room-temperature copper) high-energy linac with a linac made of niobium superconducting RF cavities.

  12. Investigation of sands subjected to dynamic loading

    E-Print Network [OSTI]

    Reeves, Gary Neil

    1967-01-01T23:59:59.000Z

    become apparent that dynamic, or sud- denly applied loads, present a different type of problem to the engineer. Wind loads on tall structures, pile driving, nuclear blasts, and many other familiar loading conditions cannot be de- scribed or handled... an earthquake or nuclear blast. Also under this category of loading is the pulse which would be purposely induced to fail the soil structure for the purpose of excavation or pile driving. As part of a broader research project concerned with pile dri- ving...

  13. Compact accelerator for medical therapy

    DOE Patents [OSTI]

    Caporaso, George J.; Chen, Yu-Jiuan; Hawkins, Steven A.; Sampayan, Stephen E.; Paul, Arthur C.

    2010-05-04T23:59:59.000Z

    A compact accelerator system having an integrated particle generator-linear accelerator with a compact, small-scale construction capable of producing an energetic (.about.70-250 MeV) proton beam or other nuclei and transporting the beam direction to a medical therapy patient without the need for bending magnets or other hardware often required for remote beam transport. The integrated particle generator-accelerator is actuable as a unitary body on a support structure to enable scanning of a particle beam by direction actuation of the particle generator-accelerator.

  14. High field gradient particle accelerator

    DOE Patents [OSTI]

    Nation, J.A.; Greenwald, S.

    1989-05-30T23:59:59.000Z

    A high electric field gradient electron accelerator utilizing short duration, microwave radiation, and capable of operating at high field gradients for high energy physics applications or at reduced electric field gradients for high average current intermediate energy accelerator applications is disclosed. Particles are accelerated in a smooth bore, periodic undulating waveguide, wherein the period is so selected that the particles slip an integral number of cycles of the r.f. wave every period of the structure. This phase step of the particles produces substantially continuous acceleration in a traveling wave without transverse magnetic or other guide means for the particle. 10 figs.

  15. High field gradient particle accelerator

    DOE Patents [OSTI]

    Nation, John A. (Ithaca, NY); Greenwald, Shlomo (Haifa, IL)

    1989-01-01T23:59:59.000Z

    A high electric field gradient electron accelerator utilizing short duration, microwave radiation, and capable of operating at high field gradients for high energy physics applications or at reduced electric field gradients for high average current intermediate energy accelerator applications. Particles are accelerated in a smooth bore, periodic undulating waveguide, wherein the period is so selected that the particles slip an integral number of cycles of the r.f. wave every period of the structure. This phase step of the particles produces substantially continuous acceleration in a traveling wave without transverse magnetic or other guide means for the particle.

  16. Linear induction accelerator

    DOE Patents [OSTI]

    Buttram, M.T.; Ginn, J.W.

    1988-06-21T23:59:59.000Z

    A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities. 4 figs.

  17. Paper No. 2004-mfb-03 Kelly Page: 1 of 4 Tensile Loading of Model Caisson Foundations for Structures on Sand

    E-Print Network [OSTI]

    Byrne, Byron

    . In the particular case of offshore wind turbines, large moments are applied at foundation level by the action the ultimate capacity is large in both cases (and controlled by the cavitation of the pore fluid the coast of the UK. In the first instance many of the wind turbine structures will be founded on piles

  18. Nano-Structural Elucidation in Carbon Black Loaded NR Vulcanizate by 3D-TEM and In Situ WAXD Measurements

    SciTech Connect (OSTI)

    Ikeda,Y.; Kato, A.; Shimanuki, J.; Kohjiya, S.; Tosaka, M.; Poompradub, S.; Toki, S.; Hsiao, B.

    2007-01-01T23:59:59.000Z

    Three dimensional (3D) visualization of nanometer structure of carbon black dispersion in rubbery matrix has successfully been studied and reported in this paper. Use of 3D-TEM, which is computerized tomography combined with transmission electron microscopy (TEM), enabled us to reconstruct 3D images of carbon black aggregates in natural rubber (NR) matrix. The TEM measurements were conducted by a bright-field method on thin samples without any electron staining. The sample was subject to uni-axial tilting (+65 degree to -65 degree with 2 degree increment) in the sample chamber, and 66 TEM images were taken on each sample. These TEM images were used for computerized tomography to reconstruct the 3D image. This technique is designated as 3D-TEM. The nano-structural features observed by 3D-TEM were in conformity with the electron-conductivity results, and the percolation behavior was recognized. These results were further supplemented by in situ wide-angle X-ray diffraction (WAXD), i.e., simultaneous WAXD and tensile measurements on the sample to observe the strain-induced crystallization in NR vulcanizate. Upon tensile elongation, the crystallization was clearly observed in WAXD in the presence of carbon black, and it contributed to the tensile properties. In order to understand the performances of filled NR vulcanizates, it surely is necessary to know the structural states of the mixed nano-filler and the crystallites produced upon elongation.

  19. Accelerated Stress Testing, Qualification Testing, HAST, Field...

    Broader source: Energy.gov (indexed) [DOE]

    StaJc Mechanical Structural failures All Load Broken glass Cry---Si & TF (SimulaJon of wind Broken interconnect ribbons All and snow load) Broken Cells Cry---Si & CPV Electrical...

  20. Acceleration Fund

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041cloth DocumentationProducts (VAP) VAP7-0973 1 Introduction In theACME - AcceleratedAccelerating

  1. Structural Safety and Reliability, Corotis et al. (eds), 2001 Swets & Zeitlinger, ISBN 90 5809 197 X Moment-based fatigue load models for wind energy systems

    E-Print Network [OSTI]

    Manuel, Lance

    197 X 1 Moment-based fatigue load models for wind energy systems Steven R. Winterstein & LeRoy M. Veers Sandia National Laboratories, Wind Energy Technology Department, Albuquerque, NM 87185-0708 Keywords: load models, fatigue loads, wind energy, non-Gaussian, moment-based models, long- term, short

  2. Calculational analysis of structural activation induced by 20-100 MeV proton beam loss in high-power linear accelerators 

    E-Print Network [OSTI]

    Lee, Stacey Kirsten

    1994-01-01T23:59:59.000Z

    to obtain dose rate estimates at several locations near the accelerator. To perform these calculations, simplified computer models were developed from detailed engineering drawings of a typical high-power accelerator design. This research focused on the 20...

  3. Dynamic response of Cu4Zr54 metallic glass to high strain rate shock loading: plasticity, spall and atomic-level structures

    SciTech Connect (OSTI)

    Luo, Shengnian [Los Alamos National Laboratory; Arman, Bedri [Los Alamos National Laboratory; Germann, Timothy C [Los Alamos National Laboratory; Cagin, Tahir [TEXAS A& M UNIV

    2009-01-01T23:59:59.000Z

    We investigate dynamic response of Cu{sub 46}Zr{sub 54} metallic glass under adiabatic planar shock wave loading (one-dimensional strain) wjth molecular dynamics simulations, including Hugoniot (shock) states, shock-induced plasticity and spallation. The Hugoniot states are obtained up to 60 CPa along with the von Mises shear flow strengths, and the dynamic spall strength, at different strain rates and temperatures. The spall strengths likely represent the limiting values achievable in experiments such as laser ablation. For the steady shock states, a clear elastic-plastic transition is identified (e.g., in the shock velocity-particle velocity curve), and the shear strength shows strain-softening. However, the elastic-plastic transition across the shock front displays transient stress overshoot (hardening) above the Hugoniot elastic limit followed by a relatively sluggish relaxation to the steady shock state, and the plastic shock front steepens with increasing shock strength. The local von Mises shear strain analysis is used to characterize local deformation, and the Voronoi tessellation analysis, the corresponding short-range structures at various stages of shock, release, tension and spallation. The plasticity in this glass is manifested as localized shear transformation zones and of local structure rather than thermal origin, and void nucleation occurs preferentially at the highly shear-deformed regions. The Voronoi and shear strain analyses show that the atoms with different local structures are of different shear resistances that lead to shear localization (e.g., the atoms indexed with (0,0,12,0) are most shear-resistant, and those with (0,2,8,1) are highly prone to shear flow). The dynamic changes in local structures are consistent with the observed deformation dynamics.

  4. Plasma accelerator

    DOE Patents [OSTI]

    Wang, Zhehui (Los Alamos, NM); Barnes, Cris W. (Santa Fe, NM)

    2002-01-01T23:59:59.000Z

    There has been invented an apparatus for acceleration of a plasma having coaxially positioned, constant diameter, cylindrical electrodes which are modified to converge (for a positive polarity inner electrode and a negatively charged outer electrode) at the plasma output end of the annulus between the electrodes to achieve improved particle flux per unit of power.

  5. Plug Load

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for RenewableSpeedingBiomassPPPOPetroleum38 (1996)representative of thePlug-Load Sign In

  6. MUON ACCELERATION

    SciTech Connect (OSTI)

    BERG,S.J.

    2003-11-18T23:59:59.000Z

    One of the major motivations driving recent interest in FFAGs is their use for the cost-effective acceleration of muons. This paper summarizes the progress in this area that was achieved leading up to and at the FFAG workshop at KEK from July 7-12, 2003. Much of the relevant background and references are also given here, to give a context to the progress we have made.

  7. Velocity bunching in travelling wave accelerator with low acceleration gradient

    E-Print Network [OSTI]

    Huang, Rui-Xuan; Li, Wei-Wei; Jia, Qi-Ka

    2013-01-01T23:59:59.000Z

    We present the analytical and simulated results concerning the influences of the acceleration gradient in the velocity bunching process, which is a bunch compression scheme that uses a traveling wave accelerating structure as a compressor. Our study shows that the bunch compression application with low acceleration gradient is more tolerant to phase jitter and more successful to obtain compressed electron beam with symmetrical longitudinal distribution and low energy spread. We also present a transverse emittance compensation scheme to compensate the emittance growth caused by the increasing of the space charge force in the compressing process that is easy to be adjusted for different compressing factors.

  8. Accelerators and the Accelerator Community

    SciTech Connect (OSTI)

    Malamud, Ernest; Sessler, Andrew

    2008-06-01T23:59:59.000Z

    In this paper, standing back--looking from afar--and adopting a historical perspective, the field of accelerator science is examined. How it grew, what are the forces that made it what it is, where it is now, and what it is likely to be in the future are the subjects explored. Clearly, a great deal of personal opinion is invoked in this process.

  9. Increasing the transformer ratio at the Argonne wakefield accelerator.

    SciTech Connect (OSTI)

    Power, J.G.; Conde, M.; Liu, W.; Yusof, Z.; Gai, W.; Jing, C.; Kanareykin, A. (High Energy Physics); (Euclid Techlabs, LLC)

    2011-01-01T23:59:59.000Z

    The transformer ratio is defined as the ratio of the maximum energy gain of the witness bunch to the maximum energy loss experienced by the drive bunch (or a bunch within a multidrive bunch train). This plays an important role in the collinear wakefield acceleration scheme. A high transformer ratio is desirable since it leads to a higher overall efficiency under similar conditions (e.g. the same beam loading, the same structure, etc.). One technique to enhance the transformer ratio beyond the ordinary limit of 2 is to use a ramped bunch train. The first experimental demonstration observed a transformer ratio only marginally above 2 due to the mismatch between the drive microbunch length and the frequency of the accelerating structure [C. Jing, A. Kanareykin, J. Power, M. Conde, Z. Yusof, P. Schoessow, and W. Gai, Phys. Rev. Lett. 98, 144801 (2007)]. Recently, we revisited this experiment with an optimized microbunch length using a UV laser stacking technique at the Argonne Wakefield Accelerator facility and measured a transformer ratio of 3.4. Measurements and data analysis from these experiments are presented in detail.

  10. Influence of the Combustion Energy Release on Surface Accelerations of an HCCI Engine

    SciTech Connect (OSTI)

    Massey, Jeffery A [ORNL; Eaton, Scott J [ORNL; Wagner, Robert M [ORNL

    2009-01-01T23:59:59.000Z

    Large cyclic variability along with increased combustion noise present in low temperature combustion (LTC) modes of internal combustion engines has driven the need for fast response, robust sensors for diagnostics and feedback control. Accelerometers have been shown as a possible technology for diagnostics and feedback control of advanced LTC operation in internal combustion engines. To make better use of this technology, an improved understanding is necessary of the effect of energy release from the combustion process on engine surface vibrations. This study explores the surface acceleration response for a single-cylinder engine operating with homogeneous charge compression ignition (HCCI) combustion. Preliminary investigation of the engine surface accelerations is conducted using a finite element analysis of the engine cylinder jacket along with consideration of cylindrical modes of the engine cylinder. Measured in-cylinder pressure is utilized as a load input to the FE model to provide an initial comparison of the computed and measured surface accelerations. Additionally, the cylindrical cavity resonant modes of the engine geometry are computed and the in-cylinder pressure frequency content is examined to verify this resonant behavior. Experimental correlations between heat release and surface acceleration metrics are then used to identify specific acceleration frequency bands in which characteristics of the combustion heat release process is detected with minimal structural resonant influence. Investigation of a metric capable of indicting combustion phasing is presented. Impact of variations in the combustion energy release process on the surface accelerations is discussed.

  11. Peculiar acceleration

    E-Print Network [OSTI]

    Luca Amendola; Claudia Quercellini; Amedeo Balbi

    2007-08-08T23:59:59.000Z

    It has been proposed recently to observe the change in cosmological redshift of distant galaxies or quasars with the next generation of large telescope and ultra-stable spectrographs (the so-called Sandage-Loeb test). Here we investigate the possibility of observing the change in peculiar velocity in nearby clusters and galaxies. This ``peculiar acceleration'' could help reconstructing the gravitational potential without assuming virialization. We show that the expected effect is of the same order of magnitude of the cosmological velocity shift. Finally, we discuss how to convert the theoretical predictions into quantities directly related to observations.

  12. ACCELERATE ENERGY

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742Energy China 2015ofDepartmentDepartment of Energy ThisThistheSummaryACCELERATE ENERGY

  13. Linear Accelerator

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |Is Your HomeLatestCenter (LMI-EFRC) -Choices toLeeLinear Accelerator

  14. Accelerator Research Department B Dept. of Applied Physics

    E-Print Network [OSTI]

    Wechsler, Risa H.

    1 Accelerator Research Department B Dept. of Applied Physics E163: Laser Acceleration at the NLCTA March 11, 2002 * Spokesman. #12;2 Accelerator Research Department B Dept. of Applied PhysicsTechnical Roadmap LEAPLEAP 1. Demonstrate the physics of laser acceleration in dielectric structures 2. Develop

  15. Retrofitting unreinforced concrete masonry to resist tornado loading

    E-Print Network [OSTI]

    Dorshorst, Evan G. (Evan Gregory)

    2013-01-01T23:59:59.000Z

    Advances in structural design and building materials have significantly increased the performance of many structures under the extreme loading conditions associated with natural disasters such as earthquakes. However, ...

  16. TWO-CHANNEL DIELECTRIC WAKE FIELD ACCELERATOR

    SciTech Connect (OSTI)

    Jay L. Hirshfield

    2012-05-30T23:59:59.000Z

    Experimental results are reported for test beam acceleration and deflection in a two-channel, cm-scale, rectangular dielectric-lined wakefield accelerator structure energized by a 14-MeV drive beam. The dominant waveguide mode of the structure is at {approx}30 GHz, and the structure is configured to exhibit a high transformer ratio ({approx}12:1). Accelerated bunches in the narrow secondary channel of the structure are continuously energized via Cherenkov radiation that is emitted by a drive bunch moving in the wider primary channel. Observed energy gains and losses, transverse deflections, and changes in the test bunch charge distribution compare favorably with predictions of theory.

  17. Loading and conjugating cavity biostructures

    DOE Patents [OSTI]

    Hainfeld, J.F.

    1997-11-25T23:59:59.000Z

    Methods for the preparation and use of a biological delivery system are disclosed. The method of preparation includes the loading of a non-biological material into a biostructure having a load-bearing structure. The method also includes the removal of some of the biostructure`s contents and the loading of a non-biological material into the biostructure. The biostructure is biologically compatible with the host, and preferably is derived from the host, the host`s species or a related species. The loaded biostructure is used directly, or it can be targeted to specific cells, tissues and/or organs within a host. The targeted biostructure can be used to deliver the non-biological material to a specified tissue, organ or cell within a host for diagnostic, therapeutic or other purposes. 11 figs.

  18. Loading and conjugating cavity biostructures

    DOE Patents [OSTI]

    Hainfeld, J.F.

    1995-08-22T23:59:59.000Z

    Methods for the preparation and use of a biological delivery system are disclosed. The method of preparation includes the loading of a non-biological material into a biostructure having a load-bearing structure. The method also includes the removal of some of the biostructure`s contents and the loading of a non-biological material into the biostructure. The biostructure is biologically compatible with the host, and preferably is derived from the host, the host`s species or a related species. The loaded biostructure is used directly, or it can be targeted to specific cells, tissues and/or organs within a host. The targeted biostructure can be used to deliver the non-biological material to a specified tissue, organ or cell within a host for diagnostic, therapeutic or other purposes. 11 figs.

  19. Load Management for Industry

    E-Print Network [OSTI]

    Konsevick, W. J., Jr.

    1982-01-01T23:59:59.000Z

    customer management programs exist. EPRI Report (EM-1606) loads to beneficially alter a'utility's load curve. (Page 1-2) list them as: Load management alternatives are covered. 1. Direct or voluntary control of customer Load management methods can... and Electric Power Research Institute (EPRI) Report energy management programs. (EM-1606) states that "the objective of load manage ment is to alter the real or apparent pattern of Our load management program was designed electricity use in order to...

  20. Plasma-based accelerator structures

    E-Print Network [OSTI]

    Schroeder, C.B.

    2011-01-01T23:59:59.000Z

    by a self- modulated intense short laser pulse”. Phys. Rev.High Intensity Short Pulse Laser Plasma Experiments”. [39]Instabilities of Short-Pulse Laser Propagation through

  1. Plasma-based accelerator structures

    E-Print Network [OSTI]

    Schroeder, C.B.

    2011-01-01T23:59:59.000Z

    significant in such ultra-short laser-plasma interactions.of ultra-short electron bunches by using colliding laser

  2. for sequence accelerators

    E-Print Network [OSTI]

    Zakharov, Vladimir

    Wynn's -algorithm for sequence accelerators using high precision arithmetic Rachel Baumann University of Arizona Wynn's -algorithm for sequence accelerators using high precision arithmetic Rachel Baumann University of Arizona April 17, 2012 #12;Wynn's -algorithm for sequence accelerators using high

  3. High payload six-axis load sensor

    DOE Patents [OSTI]

    Jansen, John F. (Knoxville, TN); Lind, Randall F. (Knoxville, TN)

    2003-01-01T23:59:59.000Z

    A repairable high-payload six-axis load sensor includes a table, a base, and at least three shear-pin load transducers removably mounted between the table and the base. Removable mounting permits easy replacement of damaged shear pins. Preferably, the shear-pin load transducers are responsive to shear forces imparted along the two axes perpendicular to an axis of minimum sensitivity characteristic of the transducer. Responsive to an applied shear force, each shear-pin load transducer can produce an electrical signal proportional to the reaction force. The load sensor can further include a structure for receiving the proportional electrical signals and computing the applied load corresponding to the proportional electrical signals. The computed load can be expressed in terms of a three-dimensional XYZ Cartesian coordinate system.

  4. ACCELERATOR TEST FACILITY

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    LABORATORY PHYSICS DEPARTMENT Effective: 04012004 Page 1 of 2 Subject: Accelerator Test Facility - Linear Accelerator General Systems Guide Prepared by: Michael Zarcone...

  5. Specific features of the structure of the Z-pinch emitting region formed during the implosion of a foam-wire load at the ANGARA-5-1 facility

    SciTech Connect (OSTI)

    Mitrofanov, K. N., E-mail: mitrofan@triniti.ru; Grabovski, E. V.; Gritsuk, A. N.; Laukhin, Ya. N.; Aleksandrov, V. V.; Oleinik, G. M.; Medovshchikov, S. F. [Troitsk Institute for Innovation and Fusion Research (Russian Federation)] [Troitsk Institute for Innovation and Fusion Research (Russian Federation); Shevel'ko, A. P. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)] [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

    2013-01-15T23:59:59.000Z

    Results are presented from experimental studies of the structure of the compressed plasma of a Z-pinch produced during the implosion of a foam-wire load at the current of up to 3 MA. The foam-wire load consisted of two nested cylindrical cascades, one of which was a solid or hollow cylinder made of low-density agar-agar foam, while the other was a wire array. The wall thickness of a hollow foam cylinder was 100-200 {mu}m. The images of the pinch and its spectrum obtained with the help of multiframe X-ray cameras and a grazing incidence spectrograph with a spatial resolution were analyzed. Data on the spatial structure of the emitting regions and the soft X-ray (SXR) spectrum of the Z-pinch in the final stage of compression of a foam-wire load were obtained. The implosion modes characterized by the formation of hot regions during implosion of such loads were revealed. The characteristic scale lengths of the hot regions were determined. It is shown that the energy distribution of SXR photons in the energy range from 80 eV to 1 keV forms the spatial structure of Z-pinch images recorded during the implosion of foam-wire loads. It is revealed that the spectral density of SXR emission in the photon energy range of 300-600 eV from hot Z-pinch regions exceeds the spectral density of radiation from the neighboring Z-pinch regions by more than one order of magnitude. Groups of lines related to the absorption and emission of radiation by atoms and multicharged ions of carbon and oxygen in the outer foam cascade of a foam-wire load were recorded for the first time by analyzing the spatial distribution of the SXR spectra of multicharged ions of the Z-pinch. The groups of absorption lines of ions (C III, O III, O IV, and O VI) corresponding to absorption of SXR photons in the Z-pinch of a tungsten wire array, which served as the inner cascade of a foam-wire load, were identified. The plasma electron temperature measured from the charge composition of carbon and oxygen ions in the outer agar-agar foam cascade was 10-40 eV. During the implosion of foam-wire loads at currents of up to 3 MA, SXR pulses (h{nu} > 100 eV) with a duration of 10 ns and peak power of 3 TW were detected. It is shown that the temporal profile of single-peak and double-peak SXR pulses can be controlled by varying the parameters of the outer and inner cascades of the foam-wire load.

  6. SLAC National Accelerator Laboratory Accelerator Physics Faculty Search

    E-Print Network [OSTI]

    Ford, James

    SLAC National Accelerator Laboratory Accelerator Physics Faculty Search The SLAC National Accelerator Laboratory invites applications for a faculty appointment in Accelerator Physics (LCLS), LCLS-II, SPEAR-3, NLC Test Accelerator (NLCTA), Cathode Test Facility (CTF), the proposed

  7. The identification of inflow fluid dynamics parameters that can be used to scale fatigue loading spectra of wind turbine structural components

    SciTech Connect (OSTI)

    Kelley, N.D.

    1993-11-01T23:59:59.000Z

    We have recently shown that the alternating load fatigue distributions measured at several locations on a wind turbine operating in a turbulent flow can be described by a mixture of at least three parametric statistical models. The rainflow cycle counting of the horizontal and vertical inflow components results in a similar mixture describing the cyclic content of the wind. We believe such a description highlights the degree of non-Gaussian characteristics of the flow. We present evidence that the severity of the low-cycle, high-amplitude alternating stress loads seen by wind turbine components are a direct consequence of the degree of departure from normality in the inflow. We have examined the details of the turbulent inflow associated with series large loading events that took place on two adjacent wind turbines installed in a large wind park in San Gorgonio Pass, California. In this paper, we describe what we believe to be the agents in the flow that induced such events. We also discuss the atmospheric mechanisms that influence the low-cycle, high-amplitude range loading seen by a number of critical wind turbine components. We further present results that can be used to scale the specific distribution shape as functions of measured inflow fluid dynamics parameters.

  8. A pulse width modulated picket fence pulser to reduce accelerator start-up transients

    SciTech Connect (OSTI)

    Reass, William A [Los Alamos National Laboratory; Balmes, Anthony A [Los Alamos National Laboratory; Bradley, Joseph T [Los Alamos National Laboratory; Netz, Dana [Los Alamos National Laboratory; Sandoval, Jacob B [Los Alamos National Laboratory

    2010-01-01T23:59:59.000Z

    This paper describes a solid state modulator used to control the input beam to the Los Alamos Neutron Science Center 'LANSCE' 800 MeV accelerator. This electrostatic Ground Level Deflector (GLD) chops the beam after the 750 keV injection energy. Two GLD's are utilized, one for the 'H+' beam and another for the 'H-' beam. These modulators are mounted on the vacuum beam pipe and directly operate sets of deflection plates. To minimize the accelerator beam start up transients, the beam is let into the accelerator cavity structures by a pulse width modulated picket fence operating between 0 and 12 kV. As the deflection plate structure appears as a capacitive load, a totem-pole switching network is utilized to facilitate rise and fall times of {approx}50 ns that is able to sink and source current to minimize beam induced sidewall activation. This paper will describe the system design and provides operational results as now presently utilized on the LANSCE accelerator system.

  9. Superconducting Radiofrequency (SRF) Accelerator Cavities

    ScienceCinema (OSTI)

    Reece, Charlie

    2014-05-22T23:59:59.000Z

    Charlie Reece, an accelerator technology scientist, explains how superconducting radiofrequency accelerator cavities work.

  10. PASSIVE DETECTION OF VEHICLE LOADING

    SciTech Connect (OSTI)

    Garrett, A.

    2012-01-03T23:59:59.000Z

    The Digital Imaging and Remote Sensing Laboratory (DIRS) at the Rochester Institute of Technology, along with the Savannah River National Laboratory is investigating passive methods to quantify vehicle loading. The research described in this paper investigates multiple vehicle indicators including brake temperature, tire temperature, engine temperature, acceleration and deceleration rates, engine acoustics, suspension response, tire deformation and vibrational response. Our investigation into these variables includes building and implementing a sensing system for data collection as well as multiple full-scale vehicle tests. The sensing system includes; infrared video cameras, triaxial accelerometers, microphones, video cameras and thermocouples. The full scale testing includes both a medium size dump truck and a tractor-trailer truck on closed courses with loads spanning the full range of the vehicle's capacity. Statistical analysis of the collected data is used to determine the effectiveness of each of the indicators for characterizing the weight of a vehicle. The final sensing system will monitor multiple load indicators and combine the results to achieve a more accurate measurement than any of the indicators could provide alone.

  11. Development of Wind-and-React Bi-2212 Accelerator Magnet Technology

    SciTech Connect (OSTI)

    Godeke, A.; Cheng, D.; Dietderich, D. R.; English, C. D.; Felice, H.; Hannaford, C. R.; Prestemon, S. O.; Sabbi, G.; Scanlan, R. M.; Hikichi, Y.; Nishioka, J.; Hasegawa, T.

    2007-08-28T23:59:59.000Z

    We report on the progress in our R&D program, targeted to develop the technology for the application of Bi2Sr2CaCu2Ox (Bi-2212) in accelerator magnets. The program uses subscale coils, wound from insulated cables, to study suitable materials, heat treatment homogeneity, stability, and effects of magnetic field and thermal and electro-magnetic loads. We have addressed material and reaction related issues and report on the fabrication, heat treatment, and analysis of subscale Bi-2212 coils. Such coils can carry a current on the order of 5000 A and generate, in various support structures, magnetic fields from 2.6 to 9.9 T. Successful coils are therefore targeted towards a hybrid Nb3Sn-HTS magnet which will demonstrate the feasibility of Bi-2212 for accelerator magnets, and open a new magnetic field realm, beyond what is achievable with Nb3Sn.

  12. Buildings Stock Load Control

    E-Print Network [OSTI]

    Joutey, H. A.; Vaezi-Nejad, H.; Clemoncon, B.; Rosenstein, F.

    2006-01-01T23:59:59.000Z

    and distribution electricity infrastructures The second part presents the approach used to rise the objectives : ? To aggregat the individual loads and to analyze the impact of different strategies from load shedding to reduce peak power demand by: ? Developing...

  13. Load sensing system

    DOE Patents [OSTI]

    Sohns, Carl W. (Oak Ridge, TN); Nodine, Robert N. (Knoxville, TN); Wallace, Steven Allen (Knoxville, TN)

    1999-01-01T23:59:59.000Z

    A load sensing system inexpensively monitors the weight and temperature of stored nuclear material for long periods of time in widely variable environments. The system can include an electrostatic load cell that encodes weight and temperature into a digital signal which is sent to a remote monitor via a coaxial cable. The same cable is used to supply the load cell with power. When multiple load cells are used, vast

  14. accelerate thrombus formation: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    as a function of time as structure formation proceeds, which mimics the effect of "dark energy" with negative pressure. Hence, the "acceleration" may be merely a mirage. We...

  15. accelerator pulsed load: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    as a transform-limited pulse, with an intensity that scales as N 2 (where N is the number of electrons in the bunch), giving rise to a coherent enhancement factor of N when...

  16. Some Frontiers of Accelerator Physics

    E-Print Network [OSTI]

    Sessler, Andrew M.

    2008-01-01T23:59:59.000Z

    Some Frontiers of Accelerator Physics A.M. Sessler OctoberSOME FRONTIERS OF ACCELERATOR PHYSICS* Andrew M. Sessleris Some Frontiers of Accelerator Physics and it is most

  17. Accelerating Particles with Plasma

    SciTech Connect (OSTI)

    Litos, Michael; Hogan, Mark

    2014-11-05T23:59:59.000Z

    Researchers at SLAC explain how they use plasma wakefields to accelerate bunches of electrons to very high energies over only a short distance. Their experiments offer a possible path for the future of particle accelerators.

  18. Accelerating semantic graph databases on commodity clusters

    SciTech Connect (OSTI)

    Morari, Alessandro; Castellana, Vito G.; Haglin, David J.; Feo, John T.; Weaver, Jesse R.; Tumeo, Antonino; Villa, Oreste

    2013-10-06T23:59:59.000Z

    We are developing a full software system for accelerating semantic graph databases on commodity cluster that scales to hundreds of nodes while maintaining constant query throughput. Our framework comprises a SPARQL to C++ compiler, a library of parallel graph methods and a custom multithreaded runtime layer, which provides a Partitioned Global Address Space (PGAS) programming model with fork/join parallelism and automatic load balancing over a commodity clusters. We present preliminary results for the compiler and for the runtime.

  19. Speed And Power Control Of An Engine By Modulation Of The Load Torque

    DOE Patents [OSTI]

    Ziph, Benjamin (Ann Arbor, MI); Strodtman, Scott (Ypsilanti, MI); Rose, Thomas K (Chelsea, MI)

    1999-01-26T23:59:59.000Z

    A system and method of speed and power control for an engine in which speed and power of the engine is controlled by modulation of the load torque. The load torque is manipulated in order to cause engine speed, and hence power to be changed. To accomplish such control, the load torque undergoes a temporary excursion in the opposite direction of the desired speed and power change. The engine and the driven equipment will accelerate or decelerate accordingly as the load torque is decreased or increased, relative to the essentially fixed or constant engine torque. As the engine accelerates or decelerates, its power increases or decreases in proportion.

  20. Entanglement of Accelerating Particles

    E-Print Network [OSTI]

    W. L. Ku; M. -C. Chu

    2007-09-03T23:59:59.000Z

    We study how the entanglement of a maximally entangled pair of particles is affected when one or both of the pair are uniformly accelerated, while the detector remains in an inertial frame. We find that the entanglement is unchanged if all degrees of freedom are considered. However, particle pairs are produced, and the entanglements of different bipartite systems may change with the acceleration. In particular, the entanglement between accelerating fermions is transferred preferentially to the produced antiparticles when the acceleration is large, and the entanglement transfer is complete when the acceleration approaches infinity. However, for scalar particles, no entanglement transfer to the antiparticles is observed.

  1. Systems and methods for the magnetic insulation of accelerator electrodes in electrostatic accelerators

    DOE Patents [OSTI]

    Grisham, Larry R

    2013-12-17T23:59:59.000Z

    The present invention provides systems and methods for the magnetic insulation of accelerator electrodes in electrostatic accelerators. Advantageously, the systems and methods of the present invention improve the practically obtainable performance of these electrostatic accelerators by addressing, among other things, voltage holding problems and conditioning issues. The problems and issues are addressed by flowing electric currents along these accelerator electrodes to produce magnetic fields that envelope the accelerator electrodes and their support structures, so as to prevent very low energy electrons from leaving the surfaces of the accelerator electrodes and subsequently picking up energy from the surrounding electric field. In various applications, this magnetic insulation must only produce modest gains in voltage holding capability to represent a significant achievement.

  2. High brightness electron accelerator

    DOE Patents [OSTI]

    Sheffield, Richard L. (Los Alamos, NM); Carlsten, Bruce E. (Los Alamos, NM); Young, Lloyd M. (Los Alamos, NM)

    1994-01-01T23:59:59.000Z

    A compact high brightness linear accelerator is provided for use, e.g., in a free electron laser. The accelerator has a first plurality of acclerating cavities having end walls with four coupling slots for accelerating electrons to high velocities in the absence of quadrupole fields. A second plurality of cavities receives the high velocity electrons for further acceleration, where each of the second cavities has end walls with two coupling slots for acceleration in the absence of dipole fields. The accelerator also includes a first cavity with an extended length to provide for phase matching the electron beam along the accelerating cavities. A solenoid is provided about the photocathode that emits the electons, where the solenoid is configured to provide a substantially uniform magnetic field over the photocathode surface to minimize emittance of the electons as the electrons enter the first cavity.

  3. Load sensing system

    DOE Patents [OSTI]

    Sohns, C.W.; Nodine, R.N.; Wallace, S.A.

    1999-05-04T23:59:59.000Z

    A load sensing system inexpensively monitors the weight and temperature of stored nuclear material for long periods of time in widely variable environments. The system can include an electrostatic load cell that encodes weight and temperature into a digital signal which is sent to a remote monitor via a coaxial cable. The same cable is used to supply the load cell with power. When multiple load cells are used, vast inventories of stored nuclear material can be continuously monitored and inventoried of minimal cost. 4 figs.

  4. Load regulating expansion fixture

    DOE Patents [OSTI]

    Wagner, Lawrence M. (San Jose, CA); Strum, Michael J. (San Jose, CA)

    1998-01-01T23:59:59.000Z

    A free standing self contained device for bonding ultra thin metallic films, such as 0.001 inch beryllium foils. The device will regulate to a predetermined load for solid state bonding when heated to a bonding temperature. The device includes a load regulating feature, whereby the expansion stresses generated for bonding are regulated and self adjusting. The load regulator comprises a pair of friction isolators with a plurality of annealed copper members located therebetween. The device, with the load regulator, will adjust to and maintain a stress level needed to successfully and economically complete a leak tight bond without damaging thin foils or other delicate components.

  5. Load regulating expansion fixture

    DOE Patents [OSTI]

    Wagner, L.M.; Strum, M.J.

    1998-12-15T23:59:59.000Z

    A free standing self contained device for bonding ultra thin metallic films, such as 0.001 inch beryllium foils is disclosed. The device will regulate to a predetermined load for solid state bonding when heated to a bonding temperature. The device includes a load regulating feature, whereby the expansion stresses generated for bonding are regulated and self adjusting. The load regulator comprises a pair of friction isolators with a plurality of annealed copper members located therebetween. The device, with the load regulator, will adjust to and maintain a stress level needed to successfully and economically complete a leak tight bond without damaging thin foils or other delicate components. 1 fig.

  6. Diffusive Acceleration of Ions at Interplanetary Shocks

    E-Print Network [OSTI]

    Matthew G. Baring; Errol J. Summerlin

    2005-06-08T23:59:59.000Z

    Heliospheric shocks are excellent systems for testing theories of particle acceleration in their environs. These generally fall into two classes: (1) interplanetary shocks that are linear in their ion acceleration characteristics, with the non-thermal ions serving as test particles, and (2) non-linear systems such as the Earth's bow shock and the solar wind termination shock, where the accelerated ions strongly influence the magnetohydrodynamic structure of the shock. This paper explores the modelling of diffusive acceleration at a particular interplanetary shock, with an emphasis on explaining in situ measurements of ion distribution functions. The observational data for this event was acquired on day 292 of 1991 by the Ulysses mission. The modeling is performed using a well-known kinetic Monte Carlo simulation, which has yielded good agreement with observations at several heliospheric shocks, as have other theoretical techniques, namely hybrid plasma simulations, and numerical solution of the diffusion-convection equation. In this theory/data comparison, it is demonstrated that diffusive acceleration theory can, to first order, successfully account for both the proton distribution data near the shock, and the observation of energetic protons farther upstream of this interplanetary shock than lower energy pick-up protons, using a single turbulence parameter. The principal conclusion is that diffusive acceleration of inflowing upstream ions can model this pick-up ion-rich event without the invoking any seed pre-acceleration mechanism, though this investigation does not rule out the action of such pre-acceleration.

  7. Synthesis of polyoxometalate-loaded epoxy composites

    DOE Patents [OSTI]

    Anderson, Benjamin J

    2014-10-07T23:59:59.000Z

    The synthesis of a polyoxometalate-loaded epoxy uses a one-step cure by applying an external stimulus to release the acid from the polyoxometalate and thereby catalyze the cure reaction of the epoxy resin. Such polyoxometalate-loaded epoxy composites afford the cured epoxy unique properties imparted by the intrinsic properties of the polyoxometalate. For example, polyoxometalate-loaded epoxy composites can be used as corrosion resistant epoxy coatings, for encapsulation of electronics with improved dielectric properties, and for structural applications with improved mechanical properties.

  8. Disruptions, loads, and dynamic response of ITER

    SciTech Connect (OSTI)

    Nelson, B.; Riemer, B.; Sayer, R.; Strickler, D. [Oak Ridge National Lab., TN (United States); Barabaschi, P.; Ioki, K.; Johnson, G.; Shimizu, K.; Williamson, D. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany). International Thermonuclear Experimental Reactor (ITER) Team

    1995-12-31T23:59:59.000Z

    Plasma disruptions and the resulting electromagnetic loads are critical to the design of the vacuum vessel and in-vessel components of the International Thermonuclear Experimental Reactor (ITER). This paper describes the status of plasma disruption simulations and related analysis, including the dynamic response of the vacuum vessel and in-vessel components, stresses and deflections in the vacuum vessel, and reaction loads in the support structures.

  9. MCO loading and cask loadout technical manual

    SciTech Connect (OSTI)

    PRAGA, A.N.

    1998-10-01T23:59:59.000Z

    A compilation of the technical basis for loading a multi-canister overpack (MCO) with spent nuclear fuel and then placing the MCO into a cask for shipment to the Cold Vacuum Drying Facility. The technical basis includes a description of the process, process technology that forms the basis for loading alternatives, process control considerations, safety considerations, equipment description, and a brief facility structure description.

  10. 16 Load Data Cleansing and Bus Load

    E-Print Network [OSTI]

    Wang, Ke

    -to-day operations, system analysis in smart grids, system visualization, system performance reliability, energy..............................................................................................................397 #12;376 Smart Grids The load forecast generally provides annual peak values for the whole system saving, and accuracy in system planning [1­4]. * This work is partly supported by a collaborative

  11. Leaky Fermi accelerators

    E-Print Network [OSTI]

    Shah, Kushal; Rom-Kedar, Vered; Turaev, Dmitry

    2015-01-01T23:59:59.000Z

    A Fermi accelerator is a billiard with oscillating walls. A leaky accelerator interacts with an environment of an ideal gas at equilibrium by exchange of particles through a small hole on its boundary. Such interaction may heat the gas: we estimate the net energy flow through the hole under the assumption that the particles inside the billiard do not collide with each other and remain in the accelerator for sufficiently long time. The heat production is found to depend strongly on the type of the Fermi accelerator. An ergodic accelerator, i.e. one which has a single ergodic component, produces a weaker energy flow than a multi-component accelerator. Specifically, in the ergodic case the energy gain is independent of the hole size, whereas in the multi-component case the energy flow may be significantly increased by shrinking the hole size.

  12. THE DIELECTRIC WALL ACCELERATOR

    SciTech Connect (OSTI)

    Caporaso, G J; Chen, Y; Sampayan, S E

    2009-08-17T23:59:59.000Z

    The Dielectric Wall Accelerator (DWA), a class of induction accelerators, employs a novel insulating beam tube to impress a longitudinal electric field on a bunch of charged particles. The surface flashover characteristics of this tube may permit the attainment of accelerating gradients on the order of 100 MV/m for accelerating pulses on the order of a nanosecond in duration. A virtual traveling wave of excitation along the tube is produced at any desired speed by controlling the timing of pulse generating modules that supply a tangential electric field to the tube wall. Because of the ability to control the speed of this virtual wave, the accelerator is capable of handling any charge to mass ratio particle; hence it can be used for electrons, protons and any ion. The accelerator architectures, key technologies and development challenges will be described.

  13. Optically pulsed electron accelerator

    DOE Patents [OSTI]

    Fraser, J.S.; Sheffield, R.L.

    1985-05-20T23:59:59.000Z

    An optically pulsed electron accelerator can be used as an injector for a free electron laser and comprises a pulsed light source, such as a laser, for providing discrete incident light pulses. A photoemissive electron source emits electron bursts having the same duration as the incident light pulses when impinged upon by same. The photoemissive electron source is located on an inside wall of a radiofrequency-powered accelerator cell which accelerates the electron burst emitted by the photoemissive electron source.

  14. Optically pulsed electron accelerator

    DOE Patents [OSTI]

    Fraser, John S. (Los Alamos, NM); Sheffield, Richard L. (Los Alamos, NM)

    1987-01-01T23:59:59.000Z

    An optically pulsed electron accelerator can be used as an injector for a free electron laser and comprises a pulsed light source, such as a laser, for providing discrete incident light pulses. A photoemissive electron source emits electron bursts having the same duration as the incident light pulses when impinged upon by same. The photoemissive electron source is located on an inside wall of a radio frequency powered accelerator cell which accelerates the electron burst emitted by the photoemissive electron source.

  15. Advanced Accelerator Concepts Workshop

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    on high energy ion generation Levi Schachter Active Media Accelerators Benjamin Bowes Ultrafast 2-D radiative transport in a micron-scale aluminum plasma excited at...

  16. Accelerator Test Facility

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Test Facility Vitaly Yakimenko October 6-7, 2010 ATF User meeting DOE HE, S. Vigdor, ALD - (Contact) T. Ludlam Chair, Physics Department V. Yakimenko Director ATF, Accelerator...

  17. Accelerator Concepts Workshop

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Colliders to Synchrotron Radiation Sources. The wide scope of the workshop includes new methods of particle acceleration to high energies, techniques for production of...

  18. Charged particle accelerator grating

    DOE Patents [OSTI]

    Palmer, Robert B. (Shoreham, NY)

    1986-01-01T23:59:59.000Z

    A readily disposable and replaceable accelerator grating for a relativistic particle accelerator. The grating is formed for a plurality of liquid droplets that are directed in precisely positioned jet streams to periodically dispose rows of droplets along the borders of a predetermined particle beam path. A plurality of lasers are used to direct laser beams into the droplets, at predetermined angles, thereby to excite the droplets to support electromagnetic accelerating resonances on their surfaces. Those resonances operate to accelerate and focus particles moving along the beam path. As the droplets are distorted or destroyed by the incoming radiation, they are replaced at a predetermined frequency by other droplets supplied through the jet streams.

  19. Accelerator R&D

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Superconducting RF Module with a PBG Coupler Cell, 2013 North American Particle Accelerator Conference, Pasadena, CA, September 29 - October 4th, 2013. Evgenya I. Simakov,...

  20. Market Acceleration (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2010-09-01T23:59:59.000Z

    The fact sheet summarizes the goals and activities of the DOE Solar Energy Technologies Program efforts within its market acceleration subprogram.

  1. Accelerated quantification of critical parameters for predicting the service life and life cycle costs of chloride-laden reinforced concrete structures

    E-Print Network [OSTI]

    Pillai Gopalakrishnan, Radhakrishna

    2003-01-01T23:59:59.000Z

    systems. A parametric study with different steel reinforcement, water-cement ratios, and chloride exposure conditions indicated that the use of corrosion resistant steels will increase the overall service life and can reduce the LCC of RC structures...

  2. Note: Numerical simulation and experimental validation of accelerating voltage formation for a pulsed electron accelerator

    SciTech Connect (OSTI)

    Egorov, I., E-mail: egoris@tpu.ru [Institute of High Technology Physics, Tomsk Polytechnic University, 2a Lenin Avenue, Tomsk 634028 (Russian Federation)

    2014-06-15T23:59:59.000Z

    This paper describes the development of a computation model of a pulsed voltage generator for a repetitive electron accelerator. The model is based on a principle circuit of the generator, supplemented with the parasitics elements of the construction. Verification of the principle model was achieved by comparison of simulation with experimental results, where reasonable agreement was demonstrated for a wide range of generator load resistance.

  3. Loads on Tie-Down Systems for Floating Drilling Rigs during Hurricane Conditions

    E-Print Network [OSTI]

    Bae, Yoon Hyeok

    2010-01-16T23:59:59.000Z

    -mooring-riser coupled dynamic analysis tool CHARM3D. Based on the simulated motion and acceleration time series, the inertial and gravity loads on derrick and skid base footing are calculated. In addition to the inertial-gravity loads, wind forces exerted on the derrick...

  4. Community petascale project for accelerator science and simulation: Advancing computational science for future accelerators and accelerator technologies

    E-Print Network [OSTI]

    Spentzouris, Panagiotis

    2008-01-01T23:59:59.000Z

    program for computational accelerator physics development isof computational accelerator physics applications, withof computational accelerator physics. Under ComPASS, the

  5. Load research manual. Volume 3. Load research for advanced technologies

    SciTech Connect (OSTI)

    None

    1980-11-01T23:59:59.000Z

    This three-volume manual presents technical guidelines for electric utility load research. Special attention is given to issues raised by the load data reporting requirements of the Public Utility Regulatory Policies Act of 1978 and to problems faced by smaller utilities that are initiating load research programs. The manual includes guides to load research literature and glossaries of load research and statistical terms. In Volume 3, special load research procedures are presented for solar, wind, and cogeneration technologies.

  6. Neutrino physics at accelerators

    E-Print Network [OSTI]

    Enrique Fernandez

    2006-07-16T23:59:59.000Z

    Present and future neutrino experiments at accelerators are mainly concerned with understanding the neutrino oscillation phenomenon and its implications. Here a brief account of neutrino oscillations is given together with a description of the supporting data. Some current and planned accelerator neutrino experiments are also explained.

  7. Microscale acceleration history discriminators

    DOE Patents [OSTI]

    Polosky, Marc A. (Albuquerque, NM); Plummer, David W. (Albuquerque, NM)

    2002-01-01T23:59:59.000Z

    A new class of micromechanical acceleration history discriminators is claimed. These discriminators allow the precise differentiation of a wide range of acceleration-time histories, thereby allowing adaptive events to be triggered in response to the severity (or lack thereof) of an external environment. Such devices have applications in airbag activation, and other safety and surety applications.

  8. Accelerators (4/5)

    ScienceCinema (OSTI)

    None

    2011-10-06T23:59:59.000Z

    1a) Introduction and motivation 1b) History and accelerator types 2) Transverse beam dynamics 3a) Longitudinal beam dynamics 3b) Figure of merit of a synchrotron/collider 3c) Beam control 4) Main limiting factors 5) Technical challenges Prerequisite knowledge: Previous knowledge of accelerators is not required.

  9. Accelerators (5/5)

    ScienceCinema (OSTI)

    None

    2011-10-06T23:59:59.000Z

    1a) Introduction and motivation 1b) History and accelerator types 2) Transverse beam dynamics 3a) Longitudinal beam dynamics 3b) Figure of merit of a synchrotron/collider 3c) Beam control 4) Main limiting factors 5) Technical challenges Prerequisite knowledge: Previous knowledge of accelerators is not required.

  10. Safety of Accelerator Facilities

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2004-07-23T23:59:59.000Z

    To establish accelerator-specific safety requirements which, when supplemented by other applicable safety and health requirements, will serve to prevent injuries and illnesses associated with Department of Energy (DOE) or National Nuclear Security Administration (NNSA) accelerator operations. Cancels DOE O 420.2A. Certified 5-13-08. Canceled by DOE O 420.2C.

  11. Accelerators (3/5)

    ScienceCinema (OSTI)

    None

    2011-10-06T23:59:59.000Z

    1a) Introduction and motivation 1b) History and accelerator types 2) Transverse beam dynamics 3a) Longitudinal beam dynamics 3b) Figure of merit of a synchrotron/collider 3c) Beam control 4) Main limiting factors 5) Technical challenges Prerequisite knowledge: Previous knowledge of accelerators is not required.

  12. Safety of Accelerator Facilities

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2011-07-21T23:59:59.000Z

    The order defines accelerators and establishes accelerator specific safety requirements and approval authorities which, when supplemented by other applicable safety and health requirements, promote safe operations to ensure protection of workers, the public, and the environment. Cancels DOE O 420.2B.

  13. Safety of Accelerator Facilities

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2001-01-08T23:59:59.000Z

    To establish accelerator-specific safety requirements which, when supplemented by other applicable safety and health requirements, will serve to prevent injuries and illnesses associated with Department of Energy (DOE) or National Nuclear Security Administration (NNSA) accelerator operations. Cancels DOE O 420.2. Canceled by DOE O 420.2B.

  14. High loading uranium fuel plate

    DOE Patents [OSTI]

    Wiencek, Thomas C. (Bolingbrook, IL); Domagala, Robert F. (Indian Head Park, IL); Thresh, Henry R. (Palos Heights, IL)

    1990-01-01T23:59:59.000Z

    Two embodiments of a high uranium fuel plate are disclosed which contain a meat comprising structured uranium compound confined between a pair of diffusion bonded ductile metal cladding plates uniformly covering the meat, the meat having a uniform high fuel loading comprising a content of uranium compound greater than about 45 Vol. % at a porosity not greater than about 10 Vol. %. In a first embodiment, the meat is a plurality of parallel wires of uranium compound. In a second embodiment, the meat is a dispersion compact containing uranium compound. The fuel plates are fabricated by a hot isostatic pressing process.

  15. Testing a combined vibration and acceleration environment.

    SciTech Connect (OSTI)

    Jepsen, Richard Alan; Romero, Edward F.

    2005-01-01T23:59:59.000Z

    Sandia National Laboratories has previously tested a capability to impose a 7.5 g-rms (30 g peak) radial vibration load up to 2 kHz on a 25 lb object with superimposed 50 g acceleration at its centrifuge facility. This was accomplished by attaching a 3,000 lb Unholtz-Dickie mechanical shaker at the end of the centrifuge arm to create a 'Vibrafuge'. However, the combination of non-radial vibration directions, and linear accelerations higher than 50g's are currently not possible because of the load capabilities of the shaker and the stresses on the internal shaker components due to the combined centrifuge acceleration. Therefore, a new technique using amplified piezo-electric actuators has been developed to surpass the limitations of the mechanical shaker system. They are lightweight, modular and would overcome several limitations presented by the current shaker. They are 'scalable', that is, adding more piezo-electric units in parallel or in series can support larger-weight test articles or displacement/frequency regimes. In addition, the units could be mounted on the centrifuge arm in various configurations to provide a variety of input directions. The design along with test results will be presented to demonstrate the capabilities and limitations of the new piezo-electric Vibrafuge.

  16. Load Monitoring CEC/LMTF Load Research Program

    SciTech Connect (OSTI)

    Huang, Zhenyu; Lesieutre, B.; Yang, Steve; Ellis, A.; Meklin, A.; Wong, B.; Gaikwad, A.; Brooks, D.; Hammerstrom, Donald J.; Phillips, John; Kosterev, Dmitry; Hoffman, M.; Ciniglio, O.; Hartwell, R.; Pourbeik, P.; Maitra, A.; Lu, Ning

    2007-11-30T23:59:59.000Z

    This white paper addresses the needs, options, current practices of load monitoring. Recommendations on load monitoring applications and future directions are also presented.

  17. Accelerated Quantum Dynamics

    E-Print Network [OSTI]

    Lynch, Morgan H

    2015-01-01T23:59:59.000Z

    In this paper we establish a formalism for the computation of observables due to acceleration-induced particle physics processes. General expressions for the transition rate, multiplicity, power, spectra, and displacement law of particles undergoing time-dependent acceleration and transitioning into a final state of arbitrary particle number are obtained. The transition rate, power, and spectra are characterised by unique polynomials of multiplicity and thermal distributions of both bosonic and fermionic statistics. The acceleration dependent multiplicity is computed in terms of the branching fractions of the associated inertial processes. The displacement law of the spectra predicts the energy of the emitted particles are directly proportional to the accelerated temperature. These results extend our understanding of particle physics into the high acceleration sector.

  18. Power System load management

    SciTech Connect (OSTI)

    Rudenko, Yu.N.; Semenov, V.A.; Sovalov, S.A.; Syutkin, B.D.

    1984-01-01T23:59:59.000Z

    The variation in demand nonuniformity is analyzed for the Unified Electric Power System of the USSR and certain interconnected power systems; the conditions for handling such nonuniformity with utilization of generating equipment having differing flexibility capabilities are also considered. On this basis approaches and techniques for acting on user loads, load management, in order to assure a balance between generated and consumed power are considered.

  19. Jar mechanism accelerator

    SciTech Connect (OSTI)

    Anderson, E.A.; Webb, D.D.

    1989-07-11T23:59:59.000Z

    This patent describes an accelerator for use with a jar mechanism in a well pipe string to enhance the jarring impact delivered to a stuck object wherein the jar mechanism includes inner and outer members for connection, respectively, between the well pipe string the stuck object. The jar mechanism members are constructed to (1) restrict relative longitudinal movement therebetween to build up energy in the well pipe string and accelerator and then (2) to release the jar mechanism members for unrestrained, free relative longitudinal movement therebetween to engage jarring surfaces on the jar mechanism members for delivering a jarring impact to the stuck object. The accelerator includes: inner and outer telescopically connected members relatively movable longitudinally to accumulate energy in the accelerator; the inner and outer accelerator members each having means for connecting the accelerator in the well pipe string; means associated with the inner and outer members for initially accomodating a predetermined minimum length of unrestrained, free relative longitudinal movement between the inner and outer accelerator members.

  20. Particle Acceleration at High-$?$ Shock Waves

    E-Print Network [OSTI]

    Jacek Niemiec

    2005-09-22T23:59:59.000Z

    First-order Fermi acceleration processes at ultrarelativistic shocks are studied with Monte Carlo simulations. The accelerated particle spectra are obtained by integrating the exact particle trajectories in a turbulent magnetic field near the shock, with a few ``realistic'' features of the field structure included. We show that the main acceleration process at oblique shocks is the particle compression at the shock. Formation of energetic spectral tails is possible in a limited energy range for highly perturbed magnetic fields. Cut-offs in the spectra occur at low energies in the resonance range considered. We relate this feature to the structure of the magnetic field downstream of the shock, where field compression produces effectively 2D turbulence in which cross-field diffusion is very small. Because of the field compression downstream, the acceleration process is inefficient also in parallel high-$\\gamma$ shocks for larger turbulence amplitudes, and features observed in oblique shocks are recovered. For small-amplitude perturbations, particle spectra are formed in a wide energy range and modifications of the acceleration process due to the existence of long-wave perturbations are observed. The critical turbulence amplitude for efficient acceleration at parallel shocks decreases with shock Lorentz factor. We also study the influence of strong short-wave perturbations downstream of the shock on the particle acceleration processes. The spectral indices obtained do not converge to the ``universal'' value . Our results indicate inefficiency of the first-order Fermi process to generate high-energy cosmic rays at ultrarelativistic shocks with the considered perturbed magnetic field structures.

  1. A comparison of measured wind park load histories with the WISPER and WISPERX load spectra

    SciTech Connect (OSTI)

    Kelley, N.D.

    1995-01-01T23:59:59.000Z

    The blade-loading histories from two adjacent Micon 65/13 wind turbines are compared with the variable-amplitude test-loading histories known as the WISPER and WISPERX spectra. These standardized loading sequences were developed from blade flapwise load histories taken from nine different horizontal-axis wind turbines operating under a wide range of conditions in Europe. The subject turbines covered a broad spectrum of rotor diameters, materials, and operating environments. The final loading sequences were developed as a joint effort of thirteen different European organizations. The goal was to develop a meaningful loading standard for horizontal-axis wind turbine blades that represents common interaction effects seen in service. In 1990, NREL made extensive load measurements on two adjacent Micon 65/13 wind turbines in simultaneous operation in the very turbulent environment of a large wind park. Further, before and during the collection of the loads data, comprehensive measurements of the statistics of the turbulent environment were obtained at both the turbines under test and at two other locations within the park. The trend to larger but lighter wind turbine structures has made an understanding of the expected lifetime loading history of paramount importance. Experience in the US has shown that the turbulence-induced loads associated with multi-row wind parks in general are much more severe than for turbines operating individually or within widely spaced environments. Multi-row wind parks are much more common in the US than in Europe. In this paper we report on our results in applying the methodology utilized to develop the WISPER and WISPERX standardized loading sequences using the available data from the Micon turbines. While the intended purpose of the WISPER sequences were not to represent a specific operating environment, we believe the exercise is useful, especially when a turbine design is likely to be installed in a multi-row wind park.

  2. Charged particle accelerator grating

    DOE Patents [OSTI]

    Palmer, R.B.

    1985-09-09T23:59:59.000Z

    A readily disposable and replaceable accelerator grating for a relativistic particle accelerator is described. The grating is formed for a plurality of liquid droplets that are directed in precisely positioned jet streams to periodically dispose rows of droplets along the borders of a predetermined particle beam path. A plurality of lasers are used to direct laser beams onto the droplets, at predetermined angles, thereby to excite the droplets to support electromagnetic accelerating resonances on their surfaces. Those resonances operate to accelerate and focus particles moving along the beam path. As the droplets are distorted or destroyed by the incoming radiation, they are replaced at a predetermined frequency by other droplets supplied through the jet streams.

  3. Accelerator on a Chip

    ScienceCinema (OSTI)

    England, Joel

    2014-07-16T23:59:59.000Z

    SLAC's Joel England explains how the same fabrication techniques used for silicon computer microchips allowed their team to create the new laser-driven particle accelerator chips. (SLAC Multimedia Communications)

  4. BNL | Accelerator Test Facility

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and new approaches to particle acceleration and x-ray generation. A next-generation ultra-fast CO2 laser based on chirped pulse amplification in isotopic gas mixtures is...

  5. CEBAF accelerator achievements

    SciTech Connect (OSTI)

    Y.C. Chao, M. Drury, C. Hovater, A. Hutton, G.A. Krafft, M. Poelker, C. Reece, M. Tiefenback

    2011-06-01T23:59:59.000Z

    In the past decade, nuclear physics users of Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) have benefited from accelerator physics advances and machine improvements. As of early 2011, CEBAF operates routinely at 6 GeV, with a 12 GeV upgrade underway. This article reports highlights of CEBAF's scientific and technological evolution in the areas of cryomodule refurbishment, RF control, polarized source development, beam transport for parity experiments, magnets and hysteresis handling, beam breakup, and helium refrigerator operational optimization.

  6. Breakthrough: Fermilab Accelerator Technology

    ScienceCinema (OSTI)

    None

    2014-08-12T23:59:59.000Z

    There are more than 30,000 particle accelerators in operation around the world. At Fermilab, scientists are collaborating with other laboratories and industry to optimize the manufacturing processes for a new type of powerful accelerator that uses superconducting niobium cavities. Experimenting with unique polishing materials, a Fermilab team has now developed an efficient and environmentally friendly way of creating cavities that can propel particles with more than 30 million volts per meter.

  7. DAMAGE LOCALIZATION USING LOAD VECTORS Dionisio Bernal

    E-Print Network [OSTI]

    Bernal, Dionisio

    DAMAGE LOCALIZATION USING LOAD VECTORS Dionisio Bernal Associate Professor Department of Civil: A technique to localize damage in structures that can be treated as linear in the pre and post-damage state is presented. Central to the approach is the computation of a set of vectors, designated as Damage Locating

  8. Summary Report of Working Group 1: Laser-Plasma Acceleration

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    structure providing a linear mechanism with potential to harness low-energy laser systems [11 orders beyond conventional machines, with quasi-monoenergetic beams at MeV-GeV energies, making them and diagnostics. This includes laser wakefield acceleration [1], where acceleration by a plasma wave excited

  9. Vacuum polarization induced by a uniformly accelerated charge

    E-Print Network [OSTI]

    B. Linet

    1995-03-30T23:59:59.000Z

    We consider a point charge fixed in the Rindler coordinates which describe a uniformly accelerated frame. We determine an integral expression of the induced charge density due to the vacuum polarization at the first order in the fine structure constant. In the case where the acceleration is weak, we give explicitly the induced electrostatic potential.

  10. Real-time POD-CFD Wind-Load Calculator for PV Systems

    SciTech Connect (OSTI)

    Huayamave, Victor [Centecorp; Divo, Eduardo [Centecorp; Ceballos, Andres [Centecorp; Barriento, Carolina [Centecorp; Stephen, Barkaszi [FSEC; Hubert, Seigneur [FSEC

    2014-03-21T23:59:59.000Z

    The primary objective of this project is to create an accurate web-based real-time wind-load calculator. This is of paramount importance for (1) the rapid and accurate assessments of the uplift and downforce loads on a PV mounting system, (2) identifying viable solutions from available mounting systems, and therefore helping reduce the cost of mounting hardware and installation. Wind loading calculations for structures are currently performed according to the American Society of Civil Engineers/ Structural Engineering Institute Standard ASCE/SEI 7; the values in this standard were calculated from simplified models that do not necessarily take into account relevant characteristics such as those from full 3D effects, end effects, turbulence generation and dissipation, as well as minor effects derived from shear forces on installation brackets and other accessories. This standard does not include provisions that address the special requirements of rooftop PV systems, and attempts to apply this standard may lead to significant design errors as wind loads are incorrectly estimated. Therefore, an accurate calculator would be of paramount importance for the preliminary assessments of the uplift and downforce loads on a PV mounting system, identifying viable solutions from available mounting systems, and therefore helping reduce the cost of the mounting system and installation. The challenge is that although a full-fledged three-dimensional computational fluid dynamics (CFD) analysis would properly and accurately capture the complete physical effects of air flow over PV systems, it would be impractical for this tool, which is intended to be a real-time web-based calculator. CFD routinely requires enormous computation times to arrive at solutions that can be deemed accurate and grid-independent even in powerful and massively parallel computer platforms. This work is expected not only to accelerate solar deployment nationwide, but also help reach the SunShot Initiative goals of reducing the total installed cost of solar energy systems by 75%. The largest percentage of the total installed cost of solar energy system is associated with balance of system cost, with up to 40% going to “soft” costs; which include customer acquisition, financing, contracting, permitting, interconnection, inspection, installation, performance, operations, and maintenance. The calculator that is being developed will provide wind loads in real-time for any solar system designs and suggest the proper installation configuration and hardware; and therefore, it is anticipated to reduce system design, installation and permitting costs.

  11. Soil-Spring Model for Fatigue Evaluation of Cyclic-Loaded Offshore Conductors

    E-Print Network [OSTI]

    Ilupeju, Olusola Ayandire

    2014-05-01T23:59:59.000Z

    more important. Design considerations and methodology for dealing with conductors and piles subjected to cyclic lateral loads, have been based on modifications to formulations for monotonic loads. Soil-structure interaction problems involving offshore...

  12. Physically Based Rendering Intersection Acceleration

    E-Print Network [OSTI]

    Kazhdan, Michael

    Physically Based Rendering (600.657) Intersection Acceleration #12;Intersection Testing Accelerated partitions: Group objects into clusters Cluster volumes may overlap #12;Uniform (Voxel) Grid Acceleration Acceleration · Trace rays through grid cells ­ Fast ­ Incremental A B C D E F Only check primitives

  13. Load research manual. Volume 1. Load research procedures

    SciTech Connect (OSTI)

    Brandenburg, L.; Clarkson, G.; Grund, Jr., C.; Leo, J.; Asbury, J.; Brandon-Brown, F.; Derderian, H.; Mueller, R.; Swaroop, R.

    1980-11-01T23:59:59.000Z

    This three-volume manual presents technical guidelines for electric utility load research. Special attention is given to issues raised by the load data reporting requirements of the Public Utility Regulatory Policies Act of 1978 and to problems faced by smaller utilities that are initiating load research programs. In Volumes 1 and 2, procedures are suggested for determining data requirements for load research, establishing the size and customer composition of a load survey sample, selecting and using equipment to record customer electricity usage, processing data tapes from the recording equipment, and analyzing the data. Statistical techniques used in customer sampling are discussed in detail. The costs of load research also are estimated, and ongoing load research programs at three utilities are described. The manual includes guides to load research literature and glossaries of load research and statistical terms.

  14. Proton linear accelerators: A theoretical and historical introduction

    SciTech Connect (OSTI)

    Lapostolle, P.M.

    1989-07-01T23:59:59.000Z

    From the beginning, the development of linear accelerators has followed a number of different directions. This report surveys the basic ideas and general principles of such machines, pointing out the problems that have led to the various improvements, with the hope that it may also aid further progress. After a brief historical survey, the principal aspects of accelerator theory are covered in some detail: phase stability, focusing, radio-frequency accelerating structures, the detailed calculation of particle dynamics, and space-charge effects at high intensities. These developments apply essentially to proton and ion accelerators, and only the last chapter deals with a few aspects relative to electrons. 134 refs.

  15. Induction accelerators for the phase rotator system

    SciTech Connect (OSTI)

    Reginato, Lou; Yu, Simon; Vanecek, Dave

    2001-07-30T23:59:59.000Z

    The principle of magnetic induction has been applied to the acceleration of high current beams in betatrons and a variety of induction accelerators. The linear induction accelerator (LIA) consists of a simple nonresonant structure where the drive voltage is applied to an axially symmetric gap that encloses a toroidal ferromagnetic material. The change in flux in the magnetic core induces an axial electric field that provides particle acceleration. This simple nonresonant (low Q) structure acts as a single turn transformer that can accelerate from hundreds of amperes to tens of kiloamperes, basically only limited by the drive impedance. The LIA is typically a low gradient structure that can provide acceleration fields of varying shapes and time durations from tens of nanoseconds to several microseconds. The efficiency of the LIA depends on the beam current and can exceed 50% if the beam current exceeds the magnetization current required by the ferromagnetic material. The acceleration voltage available is simply given by the expression V=A dB/dt. Hence, for a given cross section of material, the beam pulse duration influences the energy gain. Furthermore, a premium is put on minimizing the diameter, which impacts the total weight or cost of the magnetic material. The diameter doubly impacts the cost of the LIA since the power (cost) to drive the cores is proportional to the volume as well. The waveform requirements during the beam pulse makes it necessary to make provisions in the pulsing system to maintain the desired dB/dt during the useful part of the acceleration cycle. This is typically done two ways, by using the final stage of the pulse forming network (PFN) and by the pulse compensation network usually in close proximity of the acceleration cell. The choice of magnetic materials will be made by testing various materials both ferromagnetic and ferrimagnetic. These materials will include the nickel-iron, silicon steel amorphous and various types of ferrites not only to determine the properties that are essential in this application but the energy losses in the magnetization process which directly impact the cost.

  16. Fermilab | Science | Particle Accelerators | Fermilab's Accelerator Complex

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem NotEnergy,ARMFormsGasReleaseSpeechesHall A ThisFermilab's Accelerator Complex photo

  17. Fermilab | Science | Particle Accelerators | Leading Accelerator Technology

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem NotEnergy,ARMFormsGasReleaseSpeechesHall A ThisFermilab's Accelerator ComplexLeading

  18. Microelectromechanical acceleration-sensing apparatus

    DOE Patents [OSTI]

    Lee, Robb M. (Albuquerque, NM); Shul, Randy J. (Albuquerque, NM); Polosky, Marc A. (Albuquerque, NM); Hoke, Darren A. (Albuquerque, NM); Vernon, George E. (Rio Rancho, NM)

    2006-12-12T23:59:59.000Z

    An acceleration-sensing apparatus is disclosed which includes a moveable shuttle (i.e. a suspended mass) and a latch for capturing and holding the shuttle when an acceleration event is sensed above a predetermined threshold level. The acceleration-sensing apparatus provides a switch closure upon sensing the acceleration event and remains latched in place thereafter. Examples of the acceleration-sensing apparatus are provided which are responsive to an acceleration component in a single direction (i.e. a single-sided device) or to two oppositely-directed acceleration components (i.e. a dual-sided device). A two-stage acceleration-sensing apparatus is also disclosed which can sense two acceleration events separated in time. The acceleration-sensing apparatus of the present invention has applications, for example, in an automotive airbag deployment system.

  19. contingency Nominal loading margin

    E-Print Network [OSTI]

    Member Member Fellow Electrical and Computer Engineering Department University of Wisconsin, Madison WI 53706 USA Abstract: The change in the loading margin to voltage collapse when line outages occur the line outages of the IEEE 118 bus system. The results show the effective ranking of contingencies

  20. Cooling load estimation methods

    SciTech Connect (OSTI)

    McFarland, R.D.

    1984-01-01T23:59:59.000Z

    Ongoing research on quantifying the cooling loads in residential buildings, particularly buildings with passive solar heating systems, is described. Correlations are described that permit auxiliary cooling estimates from monthly average insolation and weather data. The objective of the research is to develop a simple analysis method, useful early in design, to estimate the annual cooling energy required of a given building.

  1. Development of Wind-and-React Bi-2212 Accelerator MagnetTechnology

    SciTech Connect (OSTI)

    Godeke, A.; Cheng, D.; Dietderich, D.R.; English, C.D.; Felice,H.; Hannaford, C.R.; Prestemon, S.O.; Sabbi, G.; Scanlan, R.M.; Hikichi,Y.; Nishioka, J.; Hasegawa, T.

    2007-08-28T23:59:59.000Z

    We report on the progress in our R&D program, targetedto develop the technology for the application of Bi2Sr2CaCu2Ox (Bi-2212)in accelerator magnets. The program uses subscale coils, wound frominsulated cables, to study suitable materials, heat treatmenthomogeneity, stability, and effects ofmagnetic field and thermal andelectro-magnetic loads. We have addressed material and reaction relatedissues and report onthe fabrication, heat treatment, and analysis ofsubscale Bi-2212 coils. Such coils can carry a current on the order of5000 A and generate, in various support structures, magnetic fields from2.6 to 9.9 T. Successful coils are therefore targeted towards a hybridNb3Sn-HTS magnet which will demonstrate the feasibility of Bi-2212 foraccelerator magnets, and open a new magnetic field realm, beyond what isachievable with Nb3Sn.

  2. Beam-driven acceleration in ultra-dense plasma media

    SciTech Connect (OSTI)

    Shin, Young-Min [Fermi National Accelerator Laboratory, Batavia, IL (United States)

    2014-09-12T23:59:59.000Z

    Accelerating parameters of beam-driven wakefield acceleration in an extremely dense plasma column has been analyzed with the dynamic framed particle-in-cell plasma simulator, and compared with analytic calculations. In the model, a witness beam undergoes a TeV/m scale alternating potential gradient excited by a micro-bunched drive beam in a 1025 m-3 and 1.6 x 1028 m-3 plasma column. The acceleration gradient, energy gain, and transformer ratio have been extensively studied in quasi-linear, linear-, and blowout-regimes. The simulation analysis indicated that in the beam-driven acceleration system a hollow plasma channel offers 20 % higher acceleration gradient by enlarging the channel radius (r) from 0.2 Ap to 0.6 .Ap in a blowout regime. This paper suggests a feasibility of TeV/m scale acceleration with a hollow crystalline structure (e.g. nanotubes) of high electron plasma density.

  3. Beam-driven acceleration in ultra-dense plasma media

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Shin, Young-Min [Fermi National Accelerator Laboratory, Batavia, IL (United States)

    2014-09-15T23:59:59.000Z

    Accelerating parameters of beam-driven wakefield acceleration in an extremely dense plasma column has been analyzed with the dynamic framed particle-in-cell plasma simulator, and compared with analytic calculations. In the model, a witness beam undergoes a TeV/m scale alternating potential gradient excited by a micro-bunched drive beam in a 1025 m-3 and 1.6 x 1028 m-3 plasma column. The acceleration gradient, energy gain, and transformer ratio have been extensively studied in quasi-linear, linear-, and blowout-regimes. The simulation analysis indicated that in the beam-driven acceleration system a hollow plasma channel offers 20 % higher acceleration gradient by enlarging the channel radius (r) from 0.2 ?p to 0.6 ?p in a blowout regime. This paper suggests a feasibility of TeV/m scale acceleration with a hollow crystalline structure (e.g. nanotubes) of high electron plasma density.

  4. Beam-driven acceleration in ultra-dense plasma media

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Shin, Young-Min

    2014-09-15T23:59:59.000Z

    Accelerating parameters of beam-driven wakefield acceleration in an extremely dense plasma column has been analyzed with the dynamic framed particle-in-cell plasma simulator, and compared with analytic calculations. In the model, a witness beam undergoes a TeV/m scale alternating potential gradient excited by a micro-bunched drive beam in a 1025 m-3 and 1.6 x 1028 m-3 plasma column. The acceleration gradient, energy gain, and transformer ratio have been extensively studied in quasi-linear, linear-, and blowout-regimes. The simulation analysis indicated that in the beam-driven acceleration system a hollow plasma channel offers 20 % higher acceleration gradient by enlarging the channel radius (r)more »from 0.2 ?p to 0.6 ?p in a blowout regime. This paper suggests a feasibility of TeV/m scale acceleration with a hollow crystalline structure (e.g. nanotubes) of high electron plasma density.« less

  5. Accelerating the development of complex products in extended enterprises

    E-Print Network [OSTI]

    Dawson, Benjamin Alan

    2011-01-01T23:59:59.000Z

    This thesis examines strategies to accelerate product development in a large commercial aerospace program structured as an extended enterprise where first and second tier suppliers perform most of the detailed product ...

  6. Overview of the SuperNova/Acceleration probe (SNAP)

    E-Print Network [OSTI]

    2002-01-01T23:59:59.000Z

    from 42 High-Redshift Supernovae,” Astrophys J. 517, pp.Observational Evidence from Supernovae for an AcceleratingEnergy with Type Ia Supernovae and Large-Scale Structure,”

  7. acceleration cavity tuner: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    power proton linear accelerators. In terms of structure design, a triple-spoke superconduct- ing cavity of the proton linac in the Eurisol project 3. Meanwhile, the study of...

  8. Investigation of resonators loaded periodic structures

    E-Print Network [OSTI]

    Diao, M'baye, S.M. Massachusetts Institute of Technology

    2006-01-01T23:59:59.000Z

    The study of metamaterials has brought about new changes in modern microwave communication systems. As predicted by Veselago some 37 years ago, substances which exhibit simultaneously, negative permittivity ([epsilon]) and ...

  9. Load rating of light pavement structures

    E-Print Network [OSTI]

    Chua, Koon Meng

    1983-01-01T23:59:59.000Z

    Deflectometer C) tY u I/s LU u I ? I I- vs FSTFI - Initial Stiffness FSTFO - Overall Stiffness FSTFI = -109. 663 e 1. 31393 x FSTFO 250 500 750 1000 1250 1500 OVERALL STIFFNESS [FROM FWDj (KIP/IN) FIGURE 18. Determination of Initial Slope... LIST OF TABLES LIST OF FIGURES INTRODUCTION TABLE OF CONTENTS Page vii 1X RELATED TECHNICAL BACKGROUND Non-Destructive Testing Techniques Computer Proarams Modelling of Pavement Materials DATA COI LEC, ION Location of Test Sites Test...

  10. Automated detection and analysis of particle beams in laser-plasma accelerator simulations

    SciTech Connect (OSTI)

    Ushizima, Daniela Mayumi; Geddes, C.G.; Cormier-Michel, E.; Bethel, E. Wes; Jacobsen, J.; Prabhat, ,; R.ubel, O.; Weber, G,; Hamann, B.

    2010-05-21T23:59:59.000Z

    Numerical simulations of laser-plasma wakefield (particle) accelerators model the acceleration of electrons trapped in plasma oscillations (wakes) left behind when an intense laser pulse propagates through the plasma. The goal of these simulations is to better understand the process involved in plasma wake generation and how electrons are trapped and accelerated by the wake. Understanding of such accelerators, and their development, offer high accelerating gradients, potentially reducing size and cost of new accelerators. One operating regime of interest is where a trapped subset of electrons loads the wake and forms an isolated group of accelerated particles with low spread in momentum and position, desirable characteristics for many applications. The electrons trapped in the wake may be accelerated to high energies, the plasma gradient in the wake reaching up to a gigaelectronvolt per centimeter. High-energy electron accelerators power intense X-ray radiation to terahertz sources, and are used in many applications including medical radiotherapy and imaging. To extract information from the simulation about the quality of the beam, a typical approach is to examine plots of the entire dataset, visually determining the adequate parameters necessary to select a subset of particles, which is then further analyzed. This procedure requires laborious examination of massive data sets over many time steps using several plots, a routine that is unfeasible for large data collections. Demand for automated analysis is growing along with the volume and size of simulations. Current 2D LWFA simulation datasets are typically between 1GB and 100GB in size, but simulations in 3D are of the order of TBs. The increase in the number of datasets and dataset sizes leads to a need for automatic routines to recognize particle patterns as particle bunches (beam of electrons) for subsequent analysis. Because of the growth in dataset size, the application of machine learning techniques for scientific data mining is increasingly considered. In plasma simulations, Bagherjeiran et al. presented a comprehensive report on applying graph-based techniques for orbit classification. They used the KAM classifier to label points and components in single and multiple orbits. Love et al. conducted an image space analysis of coherent structures in plasma simulations. They used a number of segmentation and region-growing techniques to isolate regions of interest in orbit plots. Both approaches analyzed particle accelerator data, targeting the system dynamics in terms of particle orbits. However, they did not address particle dynamics as a function of time or inspected the behavior of bunches of particles. Ruebel et al. addressed the visual analysis of massive laser wakefield acceleration (LWFA) simulation data using interactive procedures to query the data. Sophisticated visualization tools were provided to inspect the data manually. Ruebel et al. have integrated these tools to the visualization and analysis system VisIt, in addition to utilizing efficient data management based on HDF5, H5Part, and the index/query tool FastBit. In Ruebel et al. proposed automatic beam path analysis using a suite of methods to classify particles in simulation data and to analyze their temporal evolution. To enable researchers to accurately define particle beams, the method computes a set of measures based on the path of particles relative to the distance of the particles to a beam. To achieve good performance, this framework uses an analysis pipeline designed to quickly reduce the amount of data that needs to be considered in the actual path distance computation. As part of this process, region-growing methods are utilized to detect particle bunches at single time steps. Efficient data reduction is essential to enable automated analysis of large data sets as described in the next section, where data reduction methods are steered to the particular requirements of our clustering analysis. Previously, we have described the application of a set of algorithms to automate the data analys

  11. Perturbations for transient acceleration

    SciTech Connect (OSTI)

    Vargas, Cristofher Zuñiga; Zimdahl, Winfried [Universidade Federal do Espírito Santo, Departamento de Física, Av. Fernando Ferrari, 514, Campus de Goiabeiras, CEP 29075-910, Vitória, Espírito Santo (Brazil); Hipólito-Ricaldi, Wiliam S., E-mail: win_unac@hotmail.com, E-mail: hipolito@ceunes.ufes.br, E-mail: winfried.zimdahl@pq.cnpq.br [Universidade Federal do Espírito Santo, Departamento de Ciências Naturais, Grupo de Física Teórica, Rodovia BR 101 Norte, km 60, Campus de São Mateus, CEP 29932-540, São Mateus, Espírito Santo (Brazil)

    2012-04-01T23:59:59.000Z

    According to the standard ?CDM model, the accelerated expansion of the Universe will go on forever. Motivated by recent observational results, we explore the possibility of a finite phase of acceleration which asymptotically approaches another period of decelerated expansion. Extending an earlier study on a corresponding homogeneous and isotropic dynamics, in which interactions between dark matter and dark energy are crucial, the present paper also investigates the dynamics of the matter perturbations both on the Newtonian and General Relativistic (GR) levels and quantifies the potential relevance of perturbations of the dark-energy component. In the background, the model is tested against the Supernova type Ia (SNIa) data of the Constitution set and on the perturbative level against growth rate data, among them those of the WiggleZ survey, and the data of the 2dFGRS project. Our results indicate that a transient phase of accelerated expansion is not excluded by current observations.

  12. analysis load: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of a water-loaded structure excited by an impulse force is of interest for the acoustic stealth of submarines Paris-Sud XI, Universit de 43 Mechanics of Fastening System Rail...

  13. HIGH GRADIENT INDUCTION ACCELERATOR

    SciTech Connect (OSTI)

    Caporaso, G J; Sampayan, S; Chen, Y; Blackfield, D; Harris, J; Hawkins, S; Holmes, C; Krogh, M; Nelson, S; Nunnally, W; Paul, A; Poole, B; Rhodes, M; Sanders, D; Selenes, K; Sullivan, J; Wang, L; Watson, J

    2007-06-21T23:59:59.000Z

    A new type of compact induction accelerator is under development at the Lawrence Livermore National Laboratory that promises to increase the average accelerating gradient by at least an order of magnitude over that of existing induction machines. The machine is based on the use of high gradient vacuum insulators, advanced dielectric materials and switches and is stimulated by the desire for compact flash x-ray radiography sources. Research describing an extreme variant of this technology aimed at proton therapy for cancer will be described. Progress in applying this technology to several applications will be reviewed.

  14. Production, Characterization, and Acceleration of Optical Microbunches

    SciTech Connect (OSTI)

    Sears, Christopher M.S.; /Stanford U. /SLAC

    2008-06-20T23:59:59.000Z

    Optical microbunches with a spacing of 800 nm have been produced for laser acceleration research. The microbunches are produced using a inverse Free-Electron-Laser (IFEL) followed by a dispersive chicane. The microbunched electron beam is characterized by coherent optical transition radiation (COTR) with good agreement to the analytic theory for bunch formation. In a second experiment the bunches are accelerated in a second stage to achieve for the first time direct net acceleration of electrons traveling in a vacuum with visible light. This dissertation presents the theory of microbunch formation and characterization of the microbunches. It also presents the design of the experimental hardware from magnetostatic and particle tracking simulations, to fabrication and measurement of the undulator and chicane magnets. Finally, the dissertation discusses three experiments aimed at demonstrating the IFEL interaction, microbunch production, and the net acceleration of the microbunched beam. At the close of the dissertation, a separate but related research effort on the tight focusing of electrons for coupling into optical scale, Photonic Bandgap, structures is presented. This includes the design and fabrication of a strong focusing permanent magnet quadrupole triplet and an outline of an initial experiment using the triplet to observe wakefields generated by an electron beam passing through an optical scale accelerator.

  15. Load responsive hydrodynamic bearing

    DOE Patents [OSTI]

    Kalsi, Manmohan S. (Houston, TX); Somogyi, Dezso (Sugar Land, TX); Dietle, Lannie L. (Stafford, TX)

    2002-01-01T23:59:59.000Z

    A load responsive hydrodynamic bearing is provided in the form of a thrust bearing or journal bearing for supporting, guiding and lubricating a relatively rotatable member to minimize wear thereof responsive to relative rotation under severe load. In the space between spaced relatively rotatable members and in the presence of a liquid or grease lubricant, one or more continuous ring shaped integral generally circular bearing bodies each define at least one dynamic surface and a plurality of support regions. Each of the support regions defines a static surface which is oriented in generally opposed relation with the dynamic surface for contact with one of the relatively rotatable members. A plurality of flexing regions are defined by the generally circular body of the bearing and are integral with and located between adjacent support regions. Each of the flexing regions has a first beam-like element being connected by an integral flexible hinge with one of the support regions and a second beam-like element having an integral flexible hinge connection with an adjacent support region. A least one local weakening geometry of the flexing region is located intermediate the first and second beam-like elements. In response to application of load from one of the relatively rotatable elements to the bearing, the beam-like elements and the local weakening geometry become flexed, causing the dynamic surface to deform and establish a hydrodynamic geometry for wedging lubricant into the dynamic interface.

  16. The International Mass Loading Service

    E-Print Network [OSTI]

    Petrov, Leonid

    2015-01-01T23:59:59.000Z

    The International Mass Loading Service computes four loadings: a) atmospheric pressure loading; b) land water storage loading; c) oceanic tidal loading; and d) non-tidal oceanic loading. The service provides to users the mass loading time series in three forms: 1) pre-computed time series for a list of 849 space geodesy stations; 2) pre-computed time series on the global 1deg x 1deg grid; and 3) on-demand Internet service for a list of stations and a time range specified by the user. The loading displacements are provided for the time period from 1979.01.01 through present, updated on an hourly basis, and have latencies 8-20 hours.

  17. Feasibility study of channeling acceleration experiment at the Fermilab ASTA facility

    E-Print Network [OSTI]

    Shin, Young-Min; Still, Dean A; Shiltsev, Vladimir

    2015-01-01T23:59:59.000Z

    Crystal channeling technology has offered various opportunities in accelerator community with a viability of ultrahigh gradient (TV/m) acceleration for future HEP collider in Energy Frontier. The major challenge of the channeling acceleration is that ultimate acceleration gradients might require high power driver at hard x-ray regime (~ 40 keV), exceeding those conceivable for x-rays as of today, though x-ray lasers can efficiently excite solid plasma and accelerate particles inside a crystal channel. Moreover, only disposable crystal accelerators are possible at such high externally excited fields which would exceed the ionization thresholds destroying the atomic structure, so acceleration will take place only in a short time before full dissociation of the lattice. Carbon- based nanostructures have great potential with a wide range of flexibility and superior physical strength, which can be applied to channeling acceleration. This paper present beam-driven channeling acceleration concept with CNTs and discu...

  18. HIGH-POWER PRECISION CURRENT SUPPLY IST2-1000M FOR ELEMENTS OF MAGNETIC SYSTEMS OF ACCELERATORS AND

    E-Print Network [OSTI]

    Kozak, Victor R.

    HIGH-POWER PRECISION CURRENT SUPPLY IST2-1000M FOR ELEMENTS OF MAGNETIC SYSTEMS OF ACCELERATORS. These supplies are intended to power magnetic systems of accelerators, requiring high stability and low ripples current at non-inductive load % 0,02 Rate of current raise without disturbing operation of the system

  19. TOPICS IN THE PHYSICS OF PARTICLE ACCELERATORS

    E-Print Network [OSTI]

    Sessler, A.M.

    2008-01-01T23:59:59.000Z

    their whole lives to accelerator physics. As high energysome appreciation of accelerator physics. We cannot, nor dolectures on basic accelerator physics; then you will hear

  20. Progress on laser plasma accelerators

    SciTech Connect (OSTI)

    Chen, P.

    1986-04-01T23:59:59.000Z

    Several laser plasma accelerator schemes are reviewed, with emphasis on the Plasma Beat Wave Accelerator (PBWA). Theory indicates that a very high acceleration gradient, of order 1 GeV/m, can exist in the plasma wave driven by the beating lasers. Experimental results obtained on the PBWA experiment at UCLA confirms this. Parameters related to the PBWA as an accelerator system are derived, among them issues concerning the efficiency and the laser power and energy requirements are discussed.

  1. Particle Acceleration at Relativistic Shocks

    E-Print Network [OSTI]

    Yves A. Gallant

    2002-01-15T23:59:59.000Z

    I review the current status of Fermi acceleration theory at relativistic shocks. I first discuss the relativistic shock jump conditions, then describe the non-relativistic Fermi mechanism and the differences introduced by relativistic flows. I present numerical calculations of the accelerated particle spectrum, and examine the maximum energy attainable by this process. I briefly consider the minimum energy for Fermi acceleration, and a possible electron pre-acceleration mechanism.

  2. Integration of MHD load models with circuit representations the Z generator.

    SciTech Connect (OSTI)

    Jennings, Christopher A.; Ampleford, David J.; Jones, Brent Manley; McBride, Ryan D.; Bailey, James E.; Jones, Michael C.; Gomez, Matthew Robert.; Cuneo, Michael Edward; Nakhleh, Charles; Stygar, William A.; Savage, Mark Edward; Wagoner, Timothy C.; Moore, James K.

    2013-03-01T23:59:59.000Z

    MHD models of imploding loads fielded on the Z accelerator are typically driven by reduced or simplified circuit representations of the generator. The performance of many of the imploding loads is critically dependent on the current and power delivered to them, so may be strongly influenced by the generators response to their implosion. Current losses diagnosed in the transmission lines approaching the load are further known to limit the energy delivery, while exhibiting some load dependence. Through comparing the convolute performance of a wide variety of short pulse Z loads we parameterize a convolute loss resistance applicable between different experiments. We incorporate this, and other current loss terms into a transmission line representation of the Z vacuum section. We then apply this model to study the current delivery to a wide variety of wire array and MagLif style liner loads.

  3. Multidimensional spectral load balancing

    SciTech Connect (OSTI)

    Hendrickson, B.; Leland, R.

    1993-01-01T23:59:59.000Z

    We describe an algorithm for the static load balancing of scientific computations that generalizes and improves upon spectral bisection. Through a novel use of multiple eigenvectors, our new spectral algorithm can divide a computation into 4 or 8 pieces at once. These multidimensional spectral partitioning algorithms generate balanced partitions that have lower communication overhead and are less expensive to compute than those produced by spectral bisection. In addition, they automatically work to minimize message contention on a hypercube or mesh architecture. These spectral partitions are further improved by a multidimensional generalization of the Kernighan-Lin graph partitioning algorithm. Results on several computational grids are given and compared with other popular methods.

  4. A Probabilistic Model of Flooding Loads on Transverse Watertight Bulkheads in the Event of Hull Damage

    E-Print Network [OSTI]

    Bhattacharya, Baidurya

    -board explosions, weapons effects, and ex- treme wave environments. Although the structural loading or reliability WTB loads. Poisson arrival is assumed for damage events, and the maximum life-time load effect (Chan et al 2002), the effect of water in a flooded compartment on motions (Yildiz 1983, Chan et al 2002

  5. Designing and Testing Controls to Mitigate Tower Dynamic Loads in the Controls Advanced Research Turbine: Preprint

    SciTech Connect (OSTI)

    Wright, A. D.; Fingersh, L. J.; Stol, K. A.

    2007-01-01T23:59:59.000Z

    This report describes NREL's efforts to design, implement, and test advanced controls for maximizing energy extraction and reducing structural dynamic loads in wind turbines.

  6. Parametric Study of Emerging High Power Accelerator Applications Using Accelerator Systems Model (ASM)

    E-Print Network [OSTI]

    Berwald, D H; Myers, T J; Paulson, C C; Peacock, M A; Piaszczyk, C M; Rathke, J W; Piechowiak, E M

    1996-01-01T23:59:59.000Z

    Parametric Study of Emerging High Power Accelerator Applications Using Accelerator Systems Model (ASM)

  7. Radiation from Accelerated Branes

    E-Print Network [OSTI]

    Mohab Abou-Zeid; Miguel S. Costa

    2000-01-29T23:59:59.000Z

    The radiation emitted by accelerated fundamental strings and D-branes is studied within the linear approximation to the supergravity limit of string theory. We show that scalar, gauge field and gravitational radiation is generically emitted by such branes. In the case where an external scalar field accelerates the branes, we derive a Larmor-type formula for the emitted scalar radiation and study the angular distribution of the outgoing energy flux. The classical radii of the branes are calculated by means of the corresponding Thompson scattering cross sections. Within the linear approximation, the interaction of the external scalar field with the velocity fields of the branes gives a contribution to the observed gauge field and gravitational radiation.

  8. Accelerator research studies

    SciTech Connect (OSTI)

    Not Available

    1993-01-01T23:59:59.000Z

    The Accelerator Research Studies program at the University of Maryland, sponsored by the Department of Energy under grant number DE-FG05-91ER40642, is currently in the second year of a three-year funding cycle. The program consists of the following three tasks: TASK A, Study of Transport and Longitudinal Compression of Intense, High-Brightness Beams,'' (P.I., M. Reiser); TASK B, Study of Collective Ion Acceleration by Intense Electron Beams and Pseudospark Produced High Brightness Electron Beams,'' (Co-P.I.'s, W.W. Destler, M. Reiser, M.J. Rhee, and C.D. Striffler); TASK C, Study of a Gyroklystron High-Power Microwave Source for Linear Colliders,'' (Co-P.I.'s, V.L. Granatstein, W. Lawson, M. Reiser, and C.D. Striffler). In this report we document the progress that has been made during the past year for each of the three tasks.

  9. Upgrade of the Drive LINAC for the AWA Facility Dielectric Two-Beam Accelerator

    SciTech Connect (OSTI)

    Power, John; /Argonne; Conde, Manoel; /Argonne; Gai, Wei; /Argonne; Li, Zenghai; /SLAC; Mihalcea, Daniel; /Northern Illinois U.

    2012-07-02T23:59:59.000Z

    We report on the design of a seven-cell, standing-wave, 1.3-GHz rf cavity and the associated beam dynamics studies for the upgrade of the drive beamline LINAC at the Argonne Wakefield Accelerator (AWA) facility. The LINAC design is a compromise between single-bunch operation (100 nC {at} 75 MeV) and minimization of the energy droop along the bunch train during bunch-train operation. The 1.3-GHz drive bunch-train target parameters are 75 MeV, 10-20-ns macropulse duration, and 16 x 60 nC microbunches; this is equivalent to a macropulse current and beam power of 80 A and 6 GW, respectively. Each LINAC structure accelerates approximately 1000 nC in 10 ns by a voltage of 11 MV at an rf power of 10 MW. Due to the short bunch-train duration desired ({approx}10 ns) and the existing frequency (1.3 GHz), compensation of the energy droop along the bunch train is difficult to accomplish by means of the two standard techniques: time-domain or frequency-domain beam loading compensation. Therefore, to minimize the energy droop, our design is based on a large stored energy rf cavity. In this paper, we present our rf cavity optimization method, detailed rf cavity design, and beam dynamics studies of the drive beamline.

  10. Development of Wind-and-React Bi-2212 Accelerator Magnet Technology

    SciTech Connect (OSTI)

    Cheng, Daniel; Dietderich, Daniel R.; English, C.D.; Felice, Helene; Hannaford, Charles R.; Prestemon, Soren O.; Sabbi, GianLuca; Scanlan, Ron M.; Hikichi, Y.; Nishioka, J.; Hasegawa, T.; Godeke, A.

    2007-06-01T23:59:59.000Z

    We report on the progress in our R&D program, targeted to develop the technology for the application of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} (Bi-2212) in accelerator magnets. The program uses subscale coils, wound from insulated cables, to study suitable materials, heat treatment homogeneity, stability, and effects of magnetic field and thermal and electro-magnetic loads. We have addressed material and reaction related issues and report on the fabrication, heat treatment, and analysis of subscale Bi-2212 coils. Such coils can carry a current on the order of 5000 A and generate, in various support structures, magnetic fields from 2.6 to 9.9 T. Successful coils are therefore targeted towards a hybrid Nb{sub 3}Sn-HTS magnet which will demonstrate the feasibility of Bi-2212 for accelerator magnets, and open a new magnetic field realm, beyond what is achievable with Nb{sub 3}Sn.

  11. Accelerating QDP++ using GPUs

    E-Print Network [OSTI]

    Frank Winter

    2011-05-11T23:59:59.000Z

    Graphic Processing Units (GPUs) are getting increasingly important as target architectures in scientific High Performance Computing (HPC). NVIDIA established CUDA as a parallel computing architecture controlling and making use of the compute power of GPUs. CUDA provides sufficient support for C++ language elements to enable the Expression Template (ET) technique in the device memory domain. QDP++ is a C++ vector class library suited for quantum field theory which provides vector data types and expressions and forms the basis of the lattice QCD software suite Chroma. In this work accelerating QDP++ expression evaluation to a GPU was successfully implemented leveraging the ET technique and using Just-In-Time (JIT) compilation. The Portable Expression Template Engine (PETE) and the C API for CUDA kernel arguments were used to build the bridge between host and device memory domains. This provides the possibility to accelerate Chroma routines to a GPU which are typically not subject to special optimisation. As an application example a smearing routine was accelerated to execute on a GPU. A significant speed-up compared to normal CPU execution could be measured.

  12. CESR Test Accelerator

    E-Print Network [OSTI]

    Rubin, David L

    2013-01-01T23:59:59.000Z

    The Cornell Electron Storage Ring (CESR) was reconfigured in 2008 as a test accelerator to investigate the physics of ultra-low emittance damping rings. During the approximately 40 days/year available for dedicated operation as a test accelerator, specialized instrumentation is used to measure growth and mitigation of the electron cloud, emittance growth due to electron cloud, intra-beam scattering, and ions, and single and multi-bunch instabilities generated by collective effects. The flexibility of the CESR guide field optics and the integration of accelerator modeling codes with the control system have made possible an extraordinary range of experiments. Findings at CesrTA with respect to electron cloud effects, emittance tuning techniques, and beam instrumentation for measuring electron cloud, beam sizes, and beam positions are the basis for much of the design of the ILC damping rings as documented in the ILC-Technical Design Report. The program has allowed the Cornell group to cultivate the kind of talen...

  13. A facility for accelerator research and education at Fermilab

    SciTech Connect (OSTI)

    Church, Mike; Nagaitsev, Sergei; /Fermilab

    2009-01-01T23:59:59.000Z

    Fermilab is currently constructing the 'SRF Test Accelerator at the New Muon Lab' (NML). NML consists of a photo-emitted RF electron gun, followed by a bunch compressor, low energy test beamlines, SCRF accelerating structures, and high energy test beamlines. The initial primary purpose of NML will be to test superconducting RF accelerating modules for the ILC and for Fermilab's 'Project X' - a proposal for a high intensity proton source. The unique capability of NML will be to test these modules under conditions of high intensity electron beams with ILC-like beam parameters. In addition NML incorporates a photoinjector which offers significant tunability and especially the possibility to generate a bright electron beam with brightness comparable to state-of-the-art accelerators. This opens the exciting possibility of also using NML for fundamental beams research and tests of new concepts in beam manipulations and acceleration, instrumentation, and the applications of beams.

  14. Tunable Laser Plasma Accelerator based on Longitudinal Density Tailoring

    SciTech Connect (OSTI)

    Gonsalves, Anthony; Nakamura, Kei; Lin, Chen; Panasenko, Dmitriy; Shiraishi, Satomi; Sokollik, Thomas; Benedetti, Carlo; Schroeder, Carl; Geddes, Cameron; Tilborg, Jeroen van; Osterhoff, Jens; Esarey, Eric; Toth, Csaba; Leemans, Wim

    2011-07-15T23:59:59.000Z

    Laser plasma accelerators have produced high-quality electron beams with GeV energies from cm-scale devices and are being investigated as hyperspectral fs light sources producing THz to {gamma}-ray radiation and as drivers for future high-energy colliders. These applications require a high degree of stability, beam quality and tunability. Here we report on a technique to inject electrons into the accelerating field of a laser-driven plasma wave and coupling of this injector to a lower-density, separately tunable plasma for further acceleration. The technique relies on a single laser pulse powering a plasma structure with a tailored longitudinal density profile, to produce beams that can be tuned in the range of 100-400 MeV with percent-level stability, using laser pulses of less than 40 TW. The resulting device is a simple stand-alone accelerator or the front end for a multistage higher-energy accelerator.

  15. Cryogenic supply for accelerators and experiments at FAIR

    SciTech Connect (OSTI)

    Kauschke, M.; Xiang, Y.; Schroeder, C. H.; Streicher, B.; Kollmus, H. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1,64291 Darmstadt (Germany)

    2014-01-29T23:59:59.000Z

    In the coming years the new international accelerator facility FAIR (Facility for Antiproton and Ion Research), one of the largest research projects worldwide, will be built at GSI. In the final construction FAIR consists of synchrotrons and storage rings with up to 1,100 meters in circumference, two linear accelerators and about 3.5 kilometers beam transfer lines. The existing GSI accelerators serve as pre-accelerators. Partly the new machines will consist of superconducting magnets and therefore require a reliable supply with liquid helium. As the requirements for the magnets is depending on the machine and have a high variety, the cooling system is different for each machine; two phase cooling, forced flow cooling and bath cooling respectively. In addition the cold mass of the individual magnets varies between less than 1t up to 80t and some magnets will cause a dynamic heat load due to ramping that is higher than the static loads. The full cryogenic system will be operated above atmospheric pressure. The refrigeration and liquefaction power will be provided by two main cryogenic plants of 8 and 25 kW at 4K and two smaller plants next to the experiments.

  16. Recent Advances in Plasma Acceleration

    SciTech Connect (OSTI)

    Hogan, Mark

    2007-03-19T23:59:59.000Z

    The costs and the time scales of colliders intended to reach the energy frontier are such that it is important to explore new methods of accelerating particles to high energies. Plasma-based accelerators are particularly attractive because they are capable of producing accelerating fields that are orders of magnitude larger than those used in conventional colliders. In these accelerators a drive beam, either laser or particle, produces a plasma wave (wakefield) that accelerates charged particles. The ultimate utility of plasma accelerators will depend on sustaining ultra-high accelerating fields over a substantial length to achieve a significant energy gain. More than 42 GeV energy gain was achieved in an 85 cm long plasma wakefield accelerator driven by a 42 GeV electron drive beam in the Final Focus Test Beam (FFTB) Facility at SLAC. Most of the beam electrons lose energy to the plasma wave, but some electrons in the back of the same beam pulse are accelerated with a field of {approx}52 GV/m. This effectively doubles their energy, producing the energy gain of the 3 km long SLAC accelerator in less than a meter for a small fraction of the electrons in the injected bunch. Prospects for a drive-witness bunch configuration and high-gradient positron acceleration experiments planned for the SABER facility will be discussed.

  17. Muon Acceleration - RLA and FFAG

    SciTech Connect (OSTI)

    Alex Bogacz

    2011-10-01T23:59:59.000Z

    Various acceleration schemes for muons are presented. The overall goal of the acceleration systems: large acceptance acceleration to 25 GeV and 'beam shaping' can be accomplished by various fixed field accelerators at different stages. They involve three superconducting linacs: a single pass linear Pre-accelerator followed by a pair of multi-pass Recirculating Linear Accelerators (RLA) and finally a non-scaling FFAG ring. The present baseline acceleration scenario has been optimized to take maximum advantage of appropriate acceleration scheme at a given stage. The solenoid based Pre-accelerator offers very large acceptance and facilitates correction of energy gain across the bunch and significant longitudinal compression trough induced synchrotron motion. However, far off-crest acceleration reduces the effective acceleration gradient and adds complexity through the requirement of individual RF phase control for each cavity. The RLAs offer very efficient usage of high gradient superconducting RF and ability to adjust path-length after each linac pass through individual return arcs with uniformly periodic FODO optics suitable for chromatic compensation of emittance dilution with sextupoles. However, they require spreaders/recombiners switchyards at both linac ends and significant total length of the arcs. The non-scaling Fixed Field Alternating Gradient (FFAG) ring combines compactness with very large chromatic acceptance (twice the injection energy) and it allows for large number of passes through the RF (at least eight, possibly as high as 15).

  18. FINAL PROJECT REPORT LOAD MODELING TRANSMISSION RESEARCH

    E-Print Network [OSTI]

    Lesieutre, Bernard

    2013-01-01T23:59:59.000Z

    components such as power sources, loads,  transformers and components such as power sources, loads,  transformers and 

  19. Load responsive multilayer insulation performance testing

    SciTech Connect (OSTI)

    Dye, S.; Kopelove, A. [Quest Thermal Group, 6452 Fig Street Suite A, Arvada, CO 80004 (United States); Mills, G. L. [Ball Aerospace and Technologies Corp, 1600 Commerce Street, Boulder, CO 80301 (United States)

    2014-01-29T23:59:59.000Z

    Cryogenic insulation designed to operate at various pressures from one atmosphere to vacuum, with high thermal performance and light weight, is needed for cryogenically fueled space launch vehicles and aircraft. Multilayer insulation (MLI) performs well in a high vacuum, but the required vacuum shell for use in the atmosphere is heavy. Spray-on foam insulation (SOFI) is often used in these systems because of its light weight, but can have a higher heat flux than desired. We report on the continued development of Load Responsive Multilayer Insulation (LRMLI), an advanced thermal insulation system that uses dynamic beam discrete spacers that provide high thermal performance both in atmosphere and vacuum. LRMLI consists of layers of thermal radiation barriers separated and supported by micromolded polymer spacers. The spacers have low thermal conductance, and self-support a thin, lightweight vacuum shell that provides internal high vacuum in the insulation. The dynamic load responsive spacers compress to support the external load of a vacuum shell in one atmosphere, and decompress under reduced atmospheric pressure for lower heat leak. Structural load testing was performed on the spacers with various configurations. LRMLI was installed on a 400 liter tank and boil off testing with liquid nitrogen performed at various chamber pressures from one atmosphere to high vacuum. Testing was also performed with an MLI blanket on the outside of the LRMLI.

  20. SLIM, Short-pulse Technology for High Gradient Induction Accelerators

    SciTech Connect (OSTI)

    Arntz, Floyd; /Diversified Tech., Bedford; Kardo-Sysoev, A.; /Ioffe Phys. Tech. Inst.; Krasnykh, A.; /SLAC

    2008-12-16T23:59:59.000Z

    A novel short-pulse concept (SLIM) suited to a new generation of a high gradient induction particle accelerators is described herein. It applies advanced solid state semiconductor technology and modern microfabrication techniques to a coreless induction method of charged particle acceleration first proven on a macro scale in the 1960's. Because this approach avoids use of magnetic materials there is the prospect of such an accelerator working efficiently with accelerating pulses in the nanosecond range and, potentially, at megahertz pulse rates. The principal accelerator section is envisioned as a stack of coreless induction cells, the only active element within each being a single, extremely fast (subnanosecond) solid state opening switch: a Drift Step Recovery Diode (DSRD). Each coreless induction cell incorporates an electromagnetic pulse compressor in which inductive energy developed within a transmission-line feed structure over a period of tens of nanoseconds is diverted to the acceleration of the passing charge packet for a few nanoseconds by the abrupt opening of the DSRD switch. The duration of this accelerating output pulse--typically two-to-four nanoseconds--is precisely determined by a microfabricated pulse forming line connected to the cell. Because the accelerating pulse is only nanoseconds in duration, longitudinal accelerating gradients approaching 100 MeV per meter are believed to be achievable without inciting breakdown. Further benefits of this approach are that, (1) only a low voltage power supply is required to produce the high accelerating gradient, and, (2) since the DSRD switch is normally closed, voltage stress is limited to a few nanoseconds per period, hence the susceptibility to hostile environment conditions such as ionizing radiation, mismatch (e.g. in medical applications the peak beam current may be low), strong electromagnetic noise levels, etc is expected to be minimal. Finally, we observe the SLIM concept is not limited to linac applications; for instance, it could be employed to both accelerate the beam and to stabilize the superbunch mode of operation in circular track machines.

  1. Fracture of aluminum naval structures

    E-Print Network [OSTI]

    Galanis, Konstantinos, 1970-

    2007-01-01T23:59:59.000Z

    Structural catastrophic failure of naval vessels due to extreme loads such as underwater or air explosion, high velocity impact (torpedoes), or hydrodynamic loads (high speed vessels) is primarily caused by fracture. ...

  2. Observation of Enhanced Transformer Ratio in Collinear Wakefield Acceleration

    SciTech Connect (OSTI)

    Jing, C.; Kanareykin, A.; Schoessow, P. [Euclid Techlabs LLC, Solon, Ohio 44139 (United States); Power, J. G.; Conde, M.; Yusof, Z.; Gai, W. [High Energy Physics Division, Argonne National Laboratory, Argonne, Illinois-60439 (United States)

    2007-04-06T23:59:59.000Z

    One approach to future high energy particle accelerators is based on the wakefield principle: a leading high-charge drive bunch is used to excite fields in an accelerating structure or plasma that in turn accelerates a trailing low-charge witness bunch. The transformer ratio R is defined as the ratio of the maximum energy gain of the witness bunch to the maximum energy loss of the drive bunch. In general, R<2 for this configuration. A number of techniques have been proposed to overcome the transformer ratio limitation. We report here the first experimental study of the ramped bunch train (RBT) technique in a dielectric based accelerating structure. A single drive bunch was replaced by two bunches with charge ratio of 1 ratio 2.5 and a separation of 10.5 wavelengths of the fundamental mode. An average measured transformer ratio enhancement by a factor of 1.31 over the single drive bunch case was obtained.

  3. Materials considerations for a high power-density accelerator

    SciTech Connect (OSTI)

    Michelotti, R.A.; Tennant, R.A.; Bultman, N.K.; Uher, J.L.; Brewton, R.J.; Mayer, A.

    1985-01-01T23:59:59.000Z

    A 100-mA 50-MeV H/sup -/ accelerator is being designed at Los Alamos. The accelerating structures will operate at 425-MHz and will consist of a radio-frequency quadrupole (RFQ) to 2-MeV and a drift-tube linac (DTL) from 2 to 50-MeV. Design parameters have been specified to match the maximum operating capabilities of the rf system: 2-ms pulse length and 6% duty factor. The accelerating gradient in the DTL will be 4-MV/m; the maximum electric field will be approximately 1.2 times the Kilpatrick limit. These design parameters are substantially more ambitious than those of the accelerating test stand (ATS). That copper will be used on the rf-structure surfaces is not in question. Concern with residual activation and thermal management forces the investigation of materials other than the traditional carbon- and stainless-steel base materials used at Los Alamos.

  4. Nonlinear Particle Acceleration in Relativistic Shocks

    E-Print Network [OSTI]

    Donald C. Ellison; Glen P. Double

    2002-04-22T23:59:59.000Z

    Monte Carlo techniques are used to model nonlinear particle acceleration in parallel collisionless shocks of various speeds, including mildly relativistic ones. When the acceleration is efficient, the backreaction of accelerated particles modifies the shock structure and causes the compression ratio, r, to increase above test-particle values. Modified shocks with Lorentz factors less than about 3 can have compression ratios considerably greater than 3 and the momentum distribution of energetic particles no longer follows a power law relation. These results may be important for the interpretation of gamma-ray bursts if mildly relativistic internal and/or afterglow shocks play an important role accelerating particles that produce the observed radiation. For shock Lorentz factors greater than about 10, r approaches 3 and the so-called `universal' test-particle result of N(E) proportional to E^{-2.3} is obtained for sufficiently energetic particles. In all cases, the absolute normalization of the particle distribution follows directly from our model assumptions and is explicitly determined.

  5. Demand Response: Load Management Programs

    E-Print Network [OSTI]

    Simon, J.

    2012-01-01T23:59:59.000Z

    CenterPoint Load Management Programs CATEE Conference October, 2012 Agenda Outline I. General Demand Response Definition II. General Demand Response Program Rules III. CenterPoint Commercial Program IV. CenterPoint Residential Programs... V. Residential Discussion Points Demand Response Definition of load management per energy efficiency rule 25.181: ? Load control activities that result in a reduction in peak demand, or a shifting of energy usage from a peak to an off...

  6. Dynamic load balancing of applications

    DOE Patents [OSTI]

    Wheat, S.R.

    1997-05-13T23:59:59.000Z

    An application-level method for dynamically maintaining global load balance on a parallel computer, particularly on massively parallel MIMD computers is disclosed. Global load balancing is achieved by overlapping neighborhoods of processors, where each neighborhood performs local load balancing. The method supports a large class of finite element and finite difference based applications and provides an automatic element management system to which applications are easily integrated. 13 figs.

  7. A proposal for a 1 GeV plasma-wakefield acceleration experiment at SLAC

    SciTech Connect (OSTI)

    Katsouleas, T.; Lee, S. [Univ. of Southern California, Los Angeles, CA (United States); Assmann, R. [Stanford Linear Accelerator Center, Menlo Park, CA (United States)] [and others

    1997-07-01T23:59:59.000Z

    A plasma-based wakefield acceleration (PWFA) experiment is proposed that will accelerate parts of an SLC bunch by up to 1 GeV/m over a length of 1 m. A single SLC bunch is used to both induce wakefields in the one meter long plasma and to witness the resulting beam acceleration. The proposed experiment will explore and further develop the techniques that are needed to apply high-gradient plasma wakefield acceleration to large scale accelerators. The one meter length of the experiment is about two orders of magnitude larger than other high-gradient PWFA experiments and the 1 GeV/m accelerating gradient is roughly ten times larger than that achieved with conventional metallic structures. Using existing SLAC facilities, the proposed experiment will allow the study of high-gradient acceleration at the forefront of advanced accelerator research.

  8. Generic Quantum Ratchet Accelerator with Full Classical Chaos

    E-Print Network [OSTI]

    Jiangbin Gong; Paul Brumer

    2006-09-05T23:59:59.000Z

    A simple model of quantum ratchet transport that can generate unbounded linear acceleration of the quantum ratchet current is proposed, with the underlying classical dynamics fully chaotic. The results demonstrate that generic acceleration of quantum ratchet transport can occur with any type of classical phase space structure. The quantum ratchet transport with full classical chaos is also shown to be very robust to noise due to the large linear acceleration afforded by the quantum dynamics. One possible experiment allowing observation of these predictions is suggested.

  9. APT accelerator. Topical report

    SciTech Connect (OSTI)

    Lawrence, G.; Rusthoi, D. [comp.] [ed.

    1995-03-01T23:59:59.000Z

    The Accelerator Production of Tritium (APT) project, sponsored by Department of Energy Defense Programs (DOE/DP), involves the preconceptual design of an accelerator system to produce tritium for the nation`s stockpile of nuclear weapons. Tritium is an isotope of hydrogen used in nuclear weapons, and must be replenished because of radioactive decay (its half-life is approximately 12 years). Because the annual production requirements for tritium has greatly decreased since the end of the Cold War, an alternative approach to reactors for tritium production, based on a linear accelerator, is now being seriously considered. The annual tritium requirement at the time this study was undertaken (1992-1993) was 3/8 that of the 1988 goal, usually stated as 3/8-Goal. Continued reduction in the number of weapons in the stockpile has led to a revised (lower) production requirement today (March, 1995). The production requirement needed to maintain the reduced stockpile, as stated in the recent Nuclear Posture Review (summer 1994) is approximately 3/16-Goal, half the previous level. The Nuclear Posture Review also requires that the production plant be designed to accomodate a production increase (surge) to 3/8-Goal capability within five years, to allow recovery from a possible extended outage of the tritium plant. A multi-laboratory team, collaborating with several industrial partners, has developed a preconceptual APT design for the 3/8-Goal, operating at 75% capacity. The team has presented APT as a promising alternative to the reactor concepts proposed for Complex-21. Given the requirements of a reduced weapons stockpile, APT offers both significant safety, environmental, and production-fexibility advantages in comparison with reactor systems, and the prospect of successful development in time to meet the US defense requirements of the 21st Century.

  10. Sandia National Laboratories: hydrodynamic loading

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    loading High-Fidelity Hydrostructural Analysis of Ocean Renewable Power Company's (ORPC's) TidGen Turbine On March 19, 2014, in Computational Modeling & Simulation, Energy, News,...

  11. Particle Acceleration by MHD Turbulence

    E-Print Network [OSTI]

    Jungyeon Cho; A. Lazarian

    2005-10-21T23:59:59.000Z

    Recent advances in understanding of magnetohydrodynamic (MHD) turbulence call for revisions in the picture of particle acceleration. We make use of the recently established scaling of slow and fast MHD modes in strong and weak MHD turbulence to provide a systematic study of particle acceleration in magnetic pressure (low-$\\beta$) and gaseous pressure (high-$\\beta$) dominated plasmas. We consider the acceleration by large scale compressions in both slow and fast particle diffusion limits. We compare the results with the acceleration rate that arises from resonance scattering and Transit-Time Damping (TTD). We establish that fast modes accelerate particles more efficiently than slow modes. We find that particle acceleration by pitch-angle scattering and TTD dominates acceleration by slow or fast modes when the spatial diffusion rate is small. When the rate of spatial diffusion of particles is high, we establish an enhancement of the efficiency of particle acceleration by slow and fast modes in weak turbulence. We show that highly supersonic turbulence is an efficient agent for particle acceleration. We find that even incompressible turbulence can accelerate particles on the scales comparable with the particle mean free path.

  12. Accelerators AND Beams

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041cloth DocumentationProducts (VAP) VAP7-0973 1 Introduction In theACME -Toggle FermilabAccelerators

  13. Relativistic Particle Acceleration in a Folded Current Sheet

    E-Print Network [OSTI]

    S. Zenitani; M. Hoshino

    2005-05-24T23:59:59.000Z

    Two-dimensional particle simulations of a relativistic Harris current sheet of pair plasmashave demonstrated that the system is unstable to the relativistic drift kink instability (RDKI) and that a new kind of acceleration process takes place in the deformed current sheet. This process contributes to the generation of non-thermal particles and contributes to the fast magnetic dissipation in the current sheet structure. The acceleration mechanism and a brief comparison with relativistic magnetic reconnection are presented.

  14. Assessment of existing studies of wind loading on solar collectors

    SciTech Connect (OSTI)

    Murphy, L. M.

    1981-02-01T23:59:59.000Z

    In developing solar collectors, wind loading is the major structural design consideration. Wind loading investigations have focused on establishing safe bounds for steady state loading and verifying rational but initial and conservative design approaches for the various solar collector concepts. As such, the effort has been very successful, and has contributed greatly to both the recognition and qualitative understanding of many of the physical phenomena involved. Loading coefficients corresponding to mean wind velocities have been derived in these prior studies to measure the expected structural loading on the various solar collectors. Current design and testing procedures for wind loading are discussed. The test results corresponding to numerous wind tests on heliostats, parabolic troughs, parabolic dishes, and field mounted photovoltaic arrays are discussed and the applicability of the findings across the various technologies is assessed. One of the most significant consistencies in the data from all the technologies is the apparent benefit provided by fences and field shielding. Taken in toto, these data show that load reductions of three or possibly more seem feasible, though a more thorough understanding of the phenomena involved must be attained before this benefit can be realized. It is recommended that the required understanding be developed to take advantage of this benefit and that field tests be conducted to correlate with both analyses and tests.

  15. Cast dielectric composite linear accelerator

    DOE Patents [OSTI]

    Sanders, David M. (Livermore, CA); Sampayan, Stephen (Manteca, CA); Slenes, Kirk (Albuquerque, NM); Stoller, H. M. (Albuquerque, NM)

    2009-11-10T23:59:59.000Z

    A linear accelerator having cast dielectric composite layers integrally formed with conductor electrodes in a solventless fabrication process, with the cast dielectric composite preferably having a nanoparticle filler in an organic polymer such as a thermosetting resin. By incorporating this cast dielectric composite the dielectric constant of critical insulating layers of the transmission lines of the accelerator are increased while simultaneously maintaining high dielectric strengths for the accelerator.

  16. LOAD FORECASTING Eugene A. Feinberg

    E-Print Network [OSTI]

    Feinberg, Eugene A.

    , regression, artificial intelligence. 1. Introduction Accurate models for electric power load forecasting to make important decisions including decisions on pur- chasing and generating electric power, load for different operations within a utility company. The natures 269 #12;270 APPLIED MATHEMATICS FOR POWER SYSTEMS

  17. Thomas Precession by Uniform Acceleration

    E-Print Network [OSTI]

    Miroslav Pardy

    2014-12-09T23:59:59.000Z

    We determine the nonlinear transformations between coordinate systems which are mutually in a constant symmetrical accelerated motion. The maximal acceleration limit follows from the kinematical origin and it is an analogue of the maximal velocity in special relativity. We derive the dependence of mass, length, time, Doppler effect, Cherenkov effect and transition radiation angle on acceleration as an analogue phenomena in special theory of relativity. The last application of our method is the Thomas precession by uniform acceleration with the possible role in the modern physics and cosmology. The comparison of derived results with other relativistic methods is necessary.

  18. Nuclear Physics: Archived Talks - Accelerator

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Free Electron Laser (FEL) Medical Imaging Physics Topics Campaigns Meetings Recent Talks Archived Talks Accelerator Hall A Hall B Hall C 12 GeV Upgrade Experimental Techniques...

  19. Thomas Precession by Uniform Acceleration

    E-Print Network [OSTI]

    Pardy, Miroslav

    2015-01-01T23:59:59.000Z

    We determine the nonlinear transformations between coordinate systems which are mutually in a constant symmetrical accelerated motion. The maximal acceleration limit follows from the kinematical origin and it is an analogue of the maximal velocity in special relativity. We derive the dependence of mass, length, time, Doppler effect, Cherenkov effect and transition radiation angle on acceleration as an analogue phenomena in special theory of relativity. The last application of our method is the Thomas precession by uniform acceleration with the possible role in the modern physics and cosmology. The comparison of derived results with other relativistic methods is necessary.

  20. Lab Breakthrough: Fermilab Accelerator Technology

    Broader source: Energy.gov [DOE]

    Fermilab scientists developed techniques to retrofit some of the 30,000 particle accelerators in use around the world to make them more efficient and powerful.

  1. FINAL REPORT DE-FG02-04ER41317 Advanced Computation and Chaotic Dynamics for Beams and Accelerators

    SciTech Connect (OSTI)

    Cary, John R [U. Colorado

    2014-09-08T23:59:59.000Z

    During the year ending in August 2013, we continued to investigate the potential of photonic crystal (PhC) materials for acceleration purposes. We worked to characterize acceleration ability of simple PhC accelerator structures, as well as to characterize PhC materials to determine whether current fabrication techniques can meet the needs of future accelerating structures. We have also continued to design and optimize PhC accelerator structures, with the ultimate goal of finding a new kind of accelerator structure that could offer significant advantages over current RF acceleration technology. This design and optimization of these requires high performance computation, and we continue to work on methods to make such computation faster and more efficient.

  2. COMPASS, the COMmunity Petascale project for Accelerator Science and Simulation, a board computational accelerator physics initiative

    E-Print Network [OSTI]

    Cary, J.R.

    2008-01-01T23:59:59.000Z

    a broad computational accelerator physics initiative † J Rbroad computational accelerator physics initiative J R Caryand future to the accelerator physics community of the

  3. Radio frequency focused interdigital linear accelerator

    DOE Patents [OSTI]

    Swenson, Donald A.; Starling, W. Joel

    2006-08-29T23:59:59.000Z

    An interdigital (Wideroe) linear accelerator employing drift tubes, and associated support stems that couple to both the longitudinal and support stem electromagnetic fields of the linac, creating rf quadrupole fields along the axis of the linac to provide transverse focusing for the particle beam. Each drift tube comprises two separate electrodes operating at different electrical potentials as determined by cavity rf fields. Each electrode supports two fingers, pointing towards the opposite end of the drift tube, forming a four-finger geometry that produces an rf quadrupole field distribution along its axis. The fundamental periodicity of the structure is equal to one half of the particle wavelength .beta..lamda., where .beta. is the particle velocity in units of the velocity of light and .lamda. is the free space wavelength of the rf. Particles are accelerated in the gaps between drift tubes. The particle beam is focused in regions inside the drift tubes.

  4. THE RADIOLOGICAL RESEARCH ACCELERATOR FACILITY The Radiological Research Accelerator Facility

    E-Print Network [OSTI]

    THE RADIOLOGICAL RESEARCH ACCELERATOR FACILITY 71 The Radiological Research Accelerator Facility the irradiated cells. Both the microbeam and the track segment facilities continue to be utilized in various investigations of this phenomenon. The single- particle microbeam facility provides precise control of the number

  5. THE RADIOLOGICAL RESEARCH ACCELERATOR FACILITY The Radiological Research Accelerator Facility

    E-Print Network [OSTI]

    THE RADIOLOGICAL RESEARCH ACCELERATOR FACILITY 1 The Radiological Research Accelerator Facility for Radiological Research (CRR). Using the mi- crobeam facility, 10% of the cells were irradiated through particle beam as well as the first fo- cused microbeam in the new microbeam facility. · Another significant

  6. The Radiological Research Accelerator THE RADIOLOGICAL RESEARCH ACCELERATOR FACILITY

    E-Print Network [OSTI]

    The Radiological Research Accelerator Facility #12;84 THE RADIOLOGICAL RESEARCH ACCELERATOR FACILITY Director: David J. Brenner, Ph.D., D.Sc., Manager: Stephen A. Marino, M.S. An NIH SupportedV/µm 4 He ions using the microbeam facility (Exp. 73) also continued. The transformation frequency

  7. Molecular mechanisms of hydrogen loaded B-hydroquinone clathrate

    SciTech Connect (OSTI)

    Daschbach, John L.; Chang, Tsun-Mei; Corrales, Louis R.; Dang, Liem X.; McGrail, B. Peter

    2006-09-07T23:59:59.000Z

    Molecular dynamics simulations are used to investigate the molecular interactions of hydrogen loaded beta-hydroquinone clathrate. It is found that at lower temperatures, higher loadings are more stable, whereas, at higher temperatures, lower loadings are more stable. This trend can be understood based on the interactions in the system. For loadings greater than one, the repulsive forces between the guest molecules shove each other towards the attractive forces between the guest and host molecules leading to a stabilized minimum energy configuration at low temperatures. At higher temperatures greater displacements take the system away from the shallow energy minimum and the trend reverses. The asymmetries of the clathrate cage structure are due to the presence of the attractive forces at loadings greater than one that lead to confined states. The nature of the cavity structure is nearly spherical for a loading of one, leads to preferential occupation near the hydroxyl ring crowns of the cavity with a loading of two, and at higher loadings, leads to occupation of the interstitial sites (the hydroxyl rings) between cages by a single H2 molecule with the remaining molecules occupying the equatorial plane of the cavity. At higher temperatures, the cavity is more uniformly occupied for all loadings, where the occupation of the interstitial positions of the cavities leads to facile diffusion. ACKNOWLEDGEMENT This work was partially supported by NIDO (Japan), LDRD (PNNL), EERE U.S. Department of Energy, and by OBES, U.S. DOE. The Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy

  8. COAXIAL TWO-CHANNEL DIELECTRIC WAKE FIELD ACCELERATOR

    SciTech Connect (OSTI)

    Hirshfield, Jay L. [Omega-P, Inc.

    2013-04-30T23:59:59.000Z

    Theory, computations, and experimental apparatus are presented that describe and are intended to confirm novel properties of a coaxial two-channel dielectric wake field accelerator. In this configuration, an annular drive beam in the outer coaxial channel excites multimode wakefields which, in the inner channel, can accelerate a test beam to an energy much higher than the energy of the drive beam. This high transformer ratio is the result of judicious choice of the dielectric structure parameters, and of the phase separation between drive bunches and test bunches. A structure with cm-scale wakefields has been build for tests at the Argonne Wakefield Accelerator Laboratory, and a structure with mm-scale wakefields has been built for tests at the SLAC FACET facility. Both tests await scheduling by the respective facilities.

  9. Muon Collider Progress: Accelerators

    E-Print Network [OSTI]

    Michael S. Zisman

    2011-09-14T23:59:59.000Z

    A muon collider would be a powerful tool for exploring the energy-frontier with leptons, and would complement the studies now under way at the LHC. Such a device would offer several important benefits. Muons, like electrons, are point particles so the full center-of-mass energy is available for particle production. Moreover, on account of their higher mass, muons give rise to very little synchrotron radiation and produce very little beamstrahlung. The first feature permits the use of a circular collider that can make efficient use of the expensive rf system and whose footprint is compatible with an existing laboratory site. The second feature leads to a relatively narrow energy spread at the collision point. Designing an accelerator complex for a muon collider is a challenging task. Firstly, the muons are produced as a tertiary beam, so a high-power proton beam and a target that can withstand it are needed to provide the required luminosity of ~1 \\times 10^34 cm^-2s^-1. Secondly, the beam is initially produced with a large 6D phase space, which necessitates a scheme for reducing the muon beam emittance ("cooling"). Finally, the muon has a short lifetime so all beam manipulations must be done very rapidly. The Muon Accelerator Program, led by Fermilab and including a number of U.S. national laboratories and universities, has undertaken design and R&D activities aimed toward the eventual construction of a muon collider. Design features of such a facility and the supporting R&D program are described.

  10. SRF 020128-01/TESLA Report 2002-01 The optimal shape of cells of a superconducting accelerating section

    E-Print Network [OSTI]

    1 SRF 020128-01/TESLA Report 2002-01 The optimal shape of cells of a superconducting accelerating.S.A. Abstract The shape of TESLA accelerating structure can be improved to decrease maximal surface magnetic. For the TESLA accelerating cavity, as reported in [1], these values are: 0.2max =accEE , 6.42max =accEH Oe

  11. Hydrodynamic Simulation of Supernova Remnants Including Efficient Particle Acceleration

    E-Print Network [OSTI]

    Donald C. Ellison; Anne Decourchelle; Jean Ballet

    2003-08-19T23:59:59.000Z

    A number of supernova remnants (SNRs) show nonthermal X-rays assumed to be synchrotron emission from shock accelerated TeV electrons. The existence of these TeV electrons strongly suggests that the shocks in SNRs are sources of galactic cosmic rays (CRs). In addition, there is convincing evidence from broad-band studies of individual SNRs and elsewhere that the particle acceleration process in SNRs can be efficient and nonlinear. If SNR shocks are efficient particle accelerators, the production of CRs impacts the thermal properties of the shock heated, X-ray emitting gas and the SNR evolution. We report on a technique that couples nonlinear diffusive shock acceleration, including the backreaction of the accelerated particles on the structure of the forward and reverse shocks, with a hydrodynamic simulation of SNR evolution. Compared to models which ignore CRs, the most important hydrodynamical effects of placing a significant fraction of shock energy into CRs are larger shock compression ratios and lower temperatures in the shocked gas. We compare our results, which use an approximate description of the acceleration process, with a more complete model where the full CR transport equations are solved (i.e., Berezhko et al., 2002), and find excellent agreement for the CR spectrum summed over the SNR lifetime and the evolving shock compression ratio. The importance of the coupling between particle acceleration and SNR dynamics for the interpretation of broad-band continuum and thermal X-ray observations is discussed.

  12. Particle Acceleration in Relativistic Jets due to Weibel Instability

    E-Print Network [OSTI]

    K. -I. Nishikawa; P. Hardee; G. Richardson; R. Preece; H. Sol; G. J. Fishman

    2003-06-04T23:59:59.000Z

    Shock acceleration is an ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., the Buneman instability, two-streaming instability, and the Weibel instability) created in the shocks are responsible for particle (electron, positron, and ion) acceleration. Using a 3-D relativistic electromagnetic particle (REMP) code, we have investigated particle acceleration associated with a relativistic jet front propagating through an ambient plasma with and without initial magnetic fields. We find only small differences in the results between no ambient and weak ambient magnetic fields. Simulations show that the Weibel instability created in the collisionless shock front accelerates particles perpendicular and parallel to the jet propagation direction. While some Fermi acceleration may occur at the jet front, the majority of electron acceleration takes place behind the jet front and cannot be characterized as Fermi acceleration. The simulation results show that this instability is responsible for generating and amplifying highly nonuniform, small-scale magnetic fields, which contribute to the electron's transverse deflection behind the jet head. The ``jitter'' radiation (Medvedev 2000) from deflected electrons has different properties than synchrotron radiation which is calculated in a uniform magnetic field. This jitter radiation may be important to understanding the complex time evolution and/or spectral structure in gamma-ray bursts, relativistic jets, and supernova remnants.

  13. Special Issue Load Profiling Based Routing for

    E-Print Network [OSTI]

    Special Issue Load Profiling Based Routing for Guaranteed Bandwidth Flows \\Lambda IBRAHIM MATTA y the load across the set of candidate routes. In this paper, we propose the use of load profiling as an attractive alternative to load balancing for routing guaranteed bandwidth VCs (flows). Load profiling

  14. Laser acceleration of ion beams

    E-Print Network [OSTI]

    I. A. Egorova; A. V. Filatov; A. V. Prozorkevich; S. A. Smolyansky; D. B. Blaschke; M. Chubaryan

    2007-02-01T23:59:59.000Z

    We consider methods of charged particle acceleration by means of high-intensity lasers. As an application we discuss a laser booster for heavy ion beams provided, e.g. by the Dubna nuclotron. Simple estimates show that a cascade of crossed laser beams would be necessary to provide additional acceleration to gold ions of the order of GeV/nucleon.

  15. I Investigation of Pellet Acceleration

    E-Print Network [OSTI]

    I Investigation of Pellet Acceleration by an Arc heated Gas Gun An Interim Report INVESTIGATION OP PELLET ACCELERATION BY AN ARC HEATED GAS GUN* An Interim Report on the Investigations carried, and K.-V. Weisberg Abstract. Deep penetration of pellets into the JET plasma may prove to be a useful

  16. SBA Growth Accelerator Fund Competition

    Broader source: Energy.gov [DOE]

    The U.S. Small Business Administration (SBA) is accepting applications for the Growth Accelerator Fund Competition to identify the nation's innovative accelerators and similar organizations and award them cash prizes they may use to fund their operations costs and allow them to bring startup competitions to scale and new ideas to life.

  17. Wakefield measurements of SLAC linac structures at the Argonne AATF

    SciTech Connect (OSTI)

    Wang, J.W.; Loew, G.A. (Stanford Linear Accelerator Center, Menlo Park, CA (USA)); Simpson, J.; Chojnacki, E.; Gai, W.; Konecny, R.; Schoessow, P. (Argonne National Lab., IL (USA))

    1991-05-01T23:59:59.000Z

    Damped and detuned linac structures designed to minimize the effects of wakefields excited by e{sup {plus minus}} bunch trains in future linear colliders are presently under investigation at SLAC. This paper describes the results of measurements of both longitudinal and transverse wakefields performed at the ANL Advanced Accelerator Test Facility with two SLAC-built X-Band disk-loaded waveguides: a conventional 30-cavity long constant-impedance structure and a non-conventional 50-cavity long structure along which the iris and spacer diameters have been varied so as to stagger-tune the HEM{sub 11} mode frequency by 37%. The results are shown to be in excellent agreement with computations made by KN7C, TRANSVRS, TBCI, and LINACBBU. 8 refs., 5 figs.

  18. Testing in a combined vibration and acceleration environment.

    SciTech Connect (OSTI)

    Jepsen, Richard Alan; Romero, Edward F.

    2004-10-01T23:59:59.000Z

    Sandia National Laboratories has previously tested a capability to impose a 7.5 g-rms (30 g peak) radial vibration load up to 2 kHz on a 25 lb object with superimposed 50 g acceleration at its centrifuge facility. This was accomplished by attaching a 3,000 lb Unholtz-Dickie mechanical shaker at the end of the centrifuge arm to create a 'Vibrafuge'. However, the combination of non-radial vibration directions, and linear accelerations higher than 50g's are currently not possible because of the load capabilities of the shaker and the stresses on the internal shaker components due to the combined centrifuge acceleration. Therefore, a new technique using amplified piezo-electric actuators has been developed to surpass the limitations of the mechanical shaker system. They are lightweight, modular and would overcome several limitations presented by the current shaker. They are 'scalable', that is, adding more piezo-electric units in parallel or in series can support larger-weight test articles or displacement/frequency regimes. In addition, the units could be mounted on the centrifuge arm in various configurations to provide a variety of input directions. The design along with test results will be presented to demonstrate the capabilities and limitations of the new piezo-electric Vibrafuge.

  19. Cryogenic system for the MYRRHA superconducting linear accelerator

    SciTech Connect (OSTI)

    Chevalier, Nicolas R.; Junquera, Tomas [Accelerators and Cryogenic Systems, 86, rue de Paris, 91400 Orsay (France); Thermeau, Jean-Pierre [Institut de Physique Nucléaire, Université Paris Sud, 91400 Orsay (France); Romão, Luis Medeiros; Vandeplassche, Dirk [SCK-CEN, Boeretang 200, 2400 Mol (Belgium)

    2014-01-29T23:59:59.000Z

    SCK?CEN, the Belgian Nuclear Research Centre, is designing MYRRHA, a flexible fast spectrum research reactor (80 MW{sub th}), conceived as an accelerator driven system (ADS), able to operate in sub-critical and critical modes. It contains a continuous-wave (CW) superconducting (SC) proton accelerator of 600 MeV, a spallation target and a multiplying core with MOX fuel, cooled by liquid lead-bismuth (Pb-Bi). From 17 MeV onward, the SC accelerator will consist of 48 ?=0.36 spoke-loaded cavities (352 MHz), 34 ?=0.47 elliptical cavities (704 MHz) and 60 ?=0.65 elliptical cavities (704 MHz). We present an analysis of the thermal loads and of the optimal operating temperature of the cryogenic system. In particular, the low operating frequency of spoke cavities makes their operation in CW mode possible both at 4.2 K or at 2 K. Our analysis outlines the main factors that determine at what temperature the spoke cavities should be operated. We then present different cryogenic fluid distribution schemes, important characteristics (storage, transfer line, etc.) and the main challenges offered by MYRRHA in terms of cryogenics.

  20. Particle Acceleration in Astrophysical Sources

    E-Print Network [OSTI]

    Amato, Elena

    2015-01-01T23:59:59.000Z

    Astrophysical sources are extremely efficient accelerators. Some sources emit photons up to multi-TeV energies, a signature of the presence, within them, of particles with energies much higher than those achievable with the largest accelerators on Earth. Even more compelling evidence comes from the study of Cosmic Rays, charged relativistic particles that reach the Earth with incredibly high energies: at the highest energy end of their spectrum, these subatomic particles are carrying a macroscopic energy, up to a few Joules. Here I will address the best candidate sources and mechanisms as cosmic particle accelerators. I will mainly focus on Galactic sources such as Supernova Remnants and Pulsar Wind Nebulae, which being close and bright, are the best studied among astrophysical accelerators. These sources are held responsible for most of the energy that is put in relativistic particles in the Universe, but they are not thought to accelerate particles up to the highest individual energies, $\\approx 10^{20}$ eV...

  1. Particle Acceleration in Gamma-Ray Burst Jets

    E-Print Network [OSTI]

    Frank M. Rieger; Peter Duffy

    2005-11-02T23:59:59.000Z

    Gradual shear acceleration of energetic particles in gamma-ray burst (GRB) jets is considered. Special emphasis is given to the analysis of universal structured jets, and characteristic acceleration timescales are determined for a power-law and a Gaussian evolution of the bulk flow Lorentz factor $\\gamma_b$ with angle $\\phi$ from the jet axis. The results suggest that local power-law particle distributions may be generated and that higher energy particles are generally concentrated closer to the jet axis. Taking several constraints into account we show that efficient electron acceleration in gradual shear flows, with maximum particle energy successively decreasing with time, may be possible on scales larger than $r \\sim 10^{15}$ cm, provided the jet magnetic field becomes sufficiently weak and/or decreases rapidly enough with distance, while efficient acceleration of protons to ultra-high energies $> 10^{20}$ eV may be possible under a wide range of conditions.

  2. Accelerating Ab Initio Nuclear Physics Calculations with GPUs

    E-Print Network [OSTI]

    Hugh Potter; Dossay Oryspayev; Pieter Maris; Masha Sosonkina; James Vary; Sven Binder; Angelo Calci; Joachim Langhammer; Robert Roth; Ümit Çatalyürek; Erik Saule

    2014-12-18T23:59:59.000Z

    This paper describes some applications of GPU acceleration in ab initio nuclear structure calculations. Specifically, we discuss GPU acceleration of the software package MFDn, a parallel nuclear structure eigensolver. We modify the matrix construction stage to run partly on the GPU. On the Titan supercomputer at the Oak Ridge Leadership Computing Facility, this produces a speedup of approximately 2.2x - 2.7x for the matrix construction stage and 1.2x - 1.4x for the entire run.

  3. Collisionless Shocks -- Magnetic Field Generation and Particle Acceleration

    E-Print Network [OSTI]

    J. Trier Frederiksen; C. B. Hededal; T. Haugboelle; A. Nordlund

    2003-03-16T23:59:59.000Z

    We present numerical results from plasma particle simulations of collisionless shocks and ultra-relativistic counter-streaming plasmas. We demonstrate how the field-particle interactions lead to particle acceleration behind the shock-front. Further, we demonstrate how ultra relativistic counter-streaming plasmas create large scale patchy magnetic field structures and that these field structures propagate down-stream of the shock front. These results may help explain the origin of the magnetic fields and accelerated electrons responsible for afterglow synchrotron radiation from gamma ray bursts.

  4. Seismic Loading for FAST: May 2011 - August 2011

    SciTech Connect (OSTI)

    Asareh, M. A.; Prowell, I.

    2012-08-01T23:59:59.000Z

    As more wind farms are constructed in seismically active regions, earthquake loading increases in prominence for design and analysis of wind turbines. Early investigation of seismic load tended to simplify the rotor and nacelle as a lumped mass on top of the turbine tower. This simplification allowed the use of techniques developed for conventional civil structures, such as buildings, to be easily applied to wind turbines. However, interest is shifting to more detailed models that consider loads for turbine components other than the tower. These improved models offer three key capabilities in consideration of base shaking for turbines: 1) The inclusion of aerodynamics and turbine control; 2) The ability to consider component loads other than just tower loads; and 3) An improved representation of turbine response in higher modes by reducing modeling simplifications. Both experimental and numerical investigations have shown that, especially for large modern turbines, it is important to consider interaction between earthquake input, aerodynamics, and operational loads. These investigations further show that consideration of higher mode activity may be necessary in the analysis of the seismic response of turbines. Since the FAST code is already capable of considering these factors, modifications were developed that allow simulation of base shaking. This approach allows consideration of this additional load source within a framework, the FAST code that is already familiar to many researchers and practitioners.

  5. Core/corona modeling of diode-imploded annular loads

    SciTech Connect (OSTI)

    Terry, R.E.; Guillory, J.U.

    1980-11-07T23:59:59.000Z

    The effects of a tenuous exterior plasma corona with anomalous resistivity on the compression and heating of a hollow, collisional aluminum z-pinch plasma are predicted by a one-dimensional code. As the interior ('core') plasma is imploded by its axial current, the energy exchange between core and corona determines the current partition. Under the conditions of rapid core heating and compression, the increase in coronal current provides a trade-off between radial acceleration and compression, which reduces the implosion forces and softens the pitch. Combined with a heuristic account of energy and momentum transport in the strongly coupled core plasma and an approximate radiative loss calculation including Al line, recombination and Bremsstrahlung emission, the current model can provide a reasonably accurate description of imploding annular plasma loads that remain azimuthally symmetric. The implications for optimization of generator load coupling are examined.

  6. Electron beam accelerator with magnetic pulse compression and accelerator switching

    DOE Patents [OSTI]

    Birx, D.L.; Reginato, L.L.

    1984-03-22T23:59:59.000Z

    An electron beam accelerator is described comprising an electron beam generator-injector to produce a focused beam of greater than or equal to .1 MeV energy electrons; a plurality of substantially identical, aligned accelerator modules to sequentially receive and increase the kinetic energies of the beam electron by about .1-1 MeV per module. Each accelerator module includes a pulse-forming network that delivers a voltage pulse to the module of substantially .1-1 MeV maximum energy over a time duration of less than or equal to 1 ..mu..sec.

  7. Electrical and Production Load Factors 

    E-Print Network [OSTI]

    Sen, Tapajyoti

    2010-07-14T23:59:59.000Z

    Load factors are an important simplification of electrical energy use data and depend on the ratio of average demand to peak demand. Based on operating hours of a facility they serve as an important benchmarking tool for ...

  8. Sandia Wind Turbine Loads Database

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    The Sandia Wind Turbine Loads Database is divided into six files, each corresponding to approximately 16 years of simulation. The files are text files with data in columnar format. The 424MB zipped file containing six data files can be downloaded by the public. The files simulate 10-minute maximum loads for the NREL 5MW wind turbine. The details of the loads simulations can be found in the paper: “Decades of Wind Turbine Loads Simulations”, M. Barone, J. Paquette, B. Resor, and L. Manuel, AIAA2012-1288 (3.69MB PDF). Note that the site-average wind speed is 10 m/s (class I-B), not the 8.5 m/s reported in the paper.

  9. Demand Response: Load Management Programs 

    E-Print Network [OSTI]

    Simon, J.

    2012-01-01T23:59:59.000Z

    CenterPoint Load Management Programs CATEE Conference October, 2012 Agenda Outline I. General Demand Response Definition II. General Demand Response Program Rules III. CenterPoint Commercial Program IV. CenterPoint Residential Programs...

  10. Electrical and Production Load Factors

    E-Print Network [OSTI]

    Sen, Tapajyoti

    2010-07-14T23:59:59.000Z

    Load factors are an important simplification of electrical energy use data and depend on the ratio of average demand to peak demand. Based on operating hours of a facility they serve as an important benchmarking tool for the industrial sector...

  11. Building load control and optimization

    E-Print Network [OSTI]

    Xing, Hai-Yun Helen, 1976-

    2004-01-01T23:59:59.000Z

    Researchers and practitioners have proposed a variety of solutions to reduce electricity consumption and curtail peak demand. This research focuses on load control by improving the operations in existing building HVAC ...

  12. Advanced nonintrusive load monitoring system

    E-Print Network [OSTI]

    Wichakool, Warit, 1977-

    2011-01-01T23:59:59.000Z

    There is a need for flexible, inexpensive metering technologies that can be deployed in many different monitoring scenarios. Individual loads may be expected to compute information about their power consumption. Utility ...

  13. Radiological Research Accelerator Facility Service Request Form

    E-Print Network [OSTI]

    Radiological Research Accelerator Facility Service Request Form National Institute of Biomedical Imaging and Bioengineering Radiological Research Accelerator Facility Service request form Estimate when(s) to control for this experiment (if more than one, please prioritize): Radiological Research Accelerator

  14. FPGA Acceleration of Discrete Molecular Dynamics Simulation

    E-Print Network [OSTI]

    Herbordt, Martin

    ' & $ % FPGA Acceleration of Discrete Molecular Dynamics Simulation Joshua Model Thesis submitted UNIVERSITY COLLEGE OF ENGINEERING Thesis FPGA Acceleration of Discrete Molecular Dynamics Simulation Acceleration of Discrete Molecular Dynamics Simulation Joshua Model ABSTRACT Molecular dynamics simulation

  15. TOPICS IN THE PHYSICS OF PARTICLE ACCELERATORS

    E-Print Network [OSTI]

    Sessler, A.M.

    2008-01-01T23:59:59.000Z

    IN THE PHYSICS OF PARTICLE ACCELERATORS A.M. Sessler TWO-IN THE PHYSICS OF PARTICLE ACCELERATORS Andrew M. SesslerBruck, "Circular Particle Accelerators," PUF, Paris (1966).

  16. Negative hydrogen ion sources for accelerators

    SciTech Connect (OSTI)

    Moehs, D.P.; /Fermilab; Peters, J.; /DESY; Sherman, J.; /Los Alamos

    2005-08-01T23:59:59.000Z

    A variety of H{sup -} ion sources are in use at accelerator laboratories around the world. A list of these ion sources includes surface plasma sources with magnetron, Penning and surface converter geometries as well as magnetic-multipole volume sources with and without cesium. Just as varied is the means of igniting and maintaining magnetically confined plasmas. Hot and cold cathodes, radio frequency, and microwave power are all in use, as well as electron tandem source ignition. The extraction systems of accelerator H{sup -} ion sources are highly specialized utilizing magnetic and electric fields in their low energy beam transport systems to produce direct current, as well as pulsed and/or chopped beams with a variety of time structures. Within this paper, specific ion sources utilized at accelerator laboratories shall be reviewed along with the physics of surface and volume H{sup -} production in regard to source emittance. Current research trends including aperture modeling, thermal modeling, surface conditioning, and laser diagnostics will also be discussed.

  17. LIMITS OF Nb3Sn ACCELERATOR MAGNETS

    SciTech Connect (OSTI)

    Caspi, Shlomo; Ferracin, Paolo

    2005-05-01T23:59:59.000Z

    Pushing accelerator magnets beyond 10 T holds a promise of future upgrades to machines like the Tevatron at Fermilab and the LHC at CERN. Exceeding the current density limits of NbTi superconductor, Nb{sub 3}Sn is at present the only practical superconductor capable of generating fields beyond 10 T. Several Nb{sub 3}Sn pilot magnets, with fields as high as 16 T, have been built and tested, paving the way for future attempts at fields approaching 20 T. High current density conductor is required to generate high fields with reduced conductor volume. However this significantly increases the Lorentz force and stress. Future designs of coils and structures will require managing stresses of several 100's of MPa and forces of 10's of MN/m. The combined engineering requirements on size and cost of accelerator magnets will involve magnet technology that diverges from the one currently used with NbTi conductor. In this paper we shall address how far the engineering of high field magnets can be pushed, and what are the issues and limitations before such magnets can be used in particle accelerators.

  18. RFQ accelerator tuning system

    DOE Patents [OSTI]

    Bolie, Victor W. (Albuquerque, NM)

    1990-01-01T23:59:59.000Z

    A cooling system is provided for maintaining a preselected operating temperature in a device, which may be an RFQ accelerator, having a variable heat removal requirement, by circulating a cooling fluid through a cooling system remote from the device. Internal sensors in the device enable an estimated error signal to be generated from parameters which are indicative of the heat removal requirement from the device. Sensors are provided at predetermined locations in the cooling system for outputting operational temperature signals. Analog and digital computers define a control signal functionally related to the temperature signals and the estimated error signal, where the control signal is defined effective to return the device to the preselected operating temperature in a stable manner. The cooling system includes a first heat sink responsive to a first portion of the control signal to remove heat from a major portion of the circulating fluid. A second heat sink is responsive to a second portion of the control signal to remove heat from a minor portion of the circulating fluid. The cooled major and minor portions of the circulating fluid are mixed in response to a mixing portion of the control signal, which is effective to proportion the major and minor portions of the circulating fluid to establish a mixed fluid temperature which is effective to define the preselected operating temperature for the remote device. In an RFQ environment the stable temperature control enables the resonant frequency of the device to be maintained at substantially a predetermined value during transient operations.

  19. RFQ accelerator tuning system

    DOE Patents [OSTI]

    Bolie, V.W.

    1990-07-03T23:59:59.000Z

    A cooling system is provided for maintaining a preselected operating temperature in a device, which may be an RFQ accelerator, having a variable heat removal requirement, by circulating a cooling fluid through a cooling system remote from the device. Internal sensors in the device enable an estimated error signal to be generated from parameters which are indicative of the heat removal requirement from the device. Sensors are provided at predetermined locations in the cooling system for outputting operational temperature signals. Analog and digital computers define a control signal functionally related to the temperature signals and the estimated error signal, where the control signal is defined effective to return the device to the preselected operating temperature in a stable manner. The cooling system includes a first heat sink responsive to a first portion of the control signal to remove heat from a major portion of the circulating fluid. A second heat sink is responsive to a second portion of the control signal to remove heat from a minor portion of the circulating fluid. The cooled major and minor portions of the circulating fluid are mixed in response to a mixing portion of the control signal, which is effective to proportion the major and minor portions of the circulating fluid to establish a mixed fluid temperature which is effective to define the preselected operating temperature for the remote device. In an RFQ environment the stable temperature control enables the resonant frequency of the device to be maintained at substantially a predetermined value during transient operations. 3 figs.

  20. Design Considerations For Blast Loads In Pressure Vessels.

    SciTech Connect (OSTI)

    Rodriguez, E. A. (Edward A.); Nickell, Robert E.; Pepin, J. E. (Jason E.)

    2007-01-01T23:59:59.000Z

    Los Alamos National Laboratory (LANL), under the auspices of the U.S. Department of Energy (DOE) and the National Nuclear Security Administration (NNSA), conducts confined detonation experiments utilizing large, spherical, steel pressure vessels to contain the reaction products and hazardous materials from high-explosive (HE) events. Structural design and analysis considerations include: (a) Blast loading phase (i.e., impulsive loading); (b) Dynamic structural response; (c) Fragment (i.e., shrapnel) generation and penetration; (d) Ductile and non-ductile fracture; and (e) Design Criteria to ASME Code Sec. VIII, Div. 3, Impulsively Loaded Vessels. These vessels are designed for one-time-use only, efficiently utilizing the significant plastic energy absorption capability of ductile vessel materials. Alternatively, vessels may be designed for multiple-detonation events, in which case the material response is restricted to elastic or near-elastic range. Code of Federal Regulations, Title 10 Part 50 provides requirements for commercial nuclear reactor licensing; specifically dealing with accidental combustible gases in containment structures that might cause extreme loadings. The design philosophy contained herein may be applied to extreme loading events postulated to occur in nuclear reactor and non-nuclear systems or containments.

  1. Decentralized customerlevel under frequency load shedding in...

    Open Energy Info (EERE)

    enables the management of large groups of distributed loads under a single innovative control schemes to use the flexibility of electrical loads for power system purposes....

  2. Sandia Energy - Sandia Wind Turbine Loads Database

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Sandia Wind Turbine Loads Database Home Stationary Power Energy Conversion Efficiency Wind Energy Resources Wind Software Downloads Sandia Wind Turbine Loads Database Sandia Wind...

  3. Cooling load design tool for UFAD systems.

    E-Print Network [OSTI]

    Bauman, Fred; Schiavon, Stefano; Webster, Tom; Lee, Kwang Ho

    2010-01-01T23:59:59.000Z

    De- velopment of a Simplified Cooling Load Design Tool forand C. Benedek. 2007. “Cooling airflow design calculationscalculation method for design cooling loads in underfloor

  4. Laser Driven Dynamic Loading of Condensed Matter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Laser Driven Dynamic Loading of Condensed Matter Laser Driven Dynamic Loading of Condensed Matter Advanced diagnostics of experiments covering many orders of magnitude in strain...

  5. Experimental test accelerator (ETA) II

    SciTech Connect (OSTI)

    Fessenden, T.J.; Atchison, W.L.; Birx, D.L.

    1981-03-06T23:59:59.000Z

    The Experimental Test Accelerator (ETA) is designed to produce a 10 kAmp electron beam at an energy of 4.5 MeV in 40 nsec pulses at an average rate of 2 pps. The accelerator also operates in bursts of 5 pulses spaced by as little as one millisec at an average rate of 5 pps. The machine is currently operating near 80% of its design values and has accumulated over 2.5 million pulses - mostly at a rate of one pps. The plasma cathode electron source, the remainder of the accelerator, and the operating characteristics of the machine are discussed.

  6. Cosmic Particle Acceleration: Basic Issues

    E-Print Network [OSTI]

    T. W. Jones

    2000-12-22T23:59:59.000Z

    Cosmic-rays are ubiquitous, but their origins are surprisingly difficult to understand. A review is presented of some of the basic issues common to cosmic particle accelerators and arguments leading to the likely importance of diffusive shock acceleration as a general explanation. The basic theory of diffusive shock acceleration is outlined, followed by a discussion of some of the key issues that still prevent us from a full understanding of its outcomes. Some recent insights are mentioned at the end that may help direct ultimate resolution of our uncertainties.

  7. Terahertz radiation from laser accelerated electron bunches

    E-Print Network [OSTI]

    2004-01-01T23:59:59.000Z

    NUMBER 5 MAY 2004 Terahertz radiation from laser acceleratedand millimeter wave radiation from laser acceleratedNo. 5, May 2004 Terahertz radiation from laser accelerated

  8. ASTA at Fermilab: Accelerator Physics and Accelerator Education Programs at the Modern Accelerator R&D Users Facility for HEP and Accelerator Applications.

    SciTech Connect (OSTI)

    Shiltsev, V.; Piot, P.

    2013-09-01T23:59:59.000Z

    We present the current and planned beam physics research program and accelerator education program at Advanced Superconducting Test Accelerator (ASTA) at Fermilab.

  9. Accelerating CHP Deployment, United States Energy Association...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Accelerating CHP Deployment, United States Energy Association (USEA), August 2011 Accelerating CHP Deployment, United States Energy Association (USEA), August 2011 The United...

  10. Berkeley Lab Compact Accelerator Sets World Record

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Berkeley Lab Particle Accelerator Sets World Record Berkeley Lab Particle Accelerator Sets World Record Simulations at NERSC Help Validate Experimental Laser-Plasma Design December...

  11. Inverse free electron laser accelerator for advanced light sources

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Duris, J. P.; Musumeci, P.; Li, R. K.

    2012-06-01T23:59:59.000Z

    We discuss the inverse free electron laser (IFEL) scheme as a compact high gradient accelerator solution for driving advanced light sources such as a soft x-ray free electron laser amplifier or an inverse Compton scattering based gamma-ray source. In particular, we present a series of new developments aimed at improving the design of future IFEL accelerators. These include a new procedure to optimize the choice of the undulator tapering, a new concept for prebunching which greatly improves the fraction of trapped particles and the final energy spread, and a self-consistent study of beam loading effects which leads to an energy-efficient high laser-to-beam power conversion.

  12. Feed forward rf control system of the accelerator test facility

    SciTech Connect (OSTI)

    Ben-Zvi, I.; Xie, Jialin; Zhang, Renshan.

    1991-01-01T23:59:59.000Z

    We report a scheme to control the amplitude and phase of the rf accelerating field in a klystron driven electron linac. The amplitude and phase distribution within the rf pulse can be controlled to follow specified functions to reduce the energy spread of the electron beam being accelerated. The scheme employs fast beam energy and phase detectors and voltage-controlled electronic attenuator and phase shifter in the amplifier chain. The control voltages of these devices are generated by arbitrary function generators. The function generators' outputs are calculated numerically using an algorithm which takes into consideration the desired target function and the deviation (due to load variations or system parameter drift) from the target function. Results of preliminary tests on producing flat rf power and phase pulses from a high power klystron indicate that amplitude variation of {plus minus}0.2% and phase variation of {plus minus}1{degree} can be readily achieved. 4 refs., 3 figs.

  13. Accelerating DSMC data extraction.

    SciTech Connect (OSTI)

    Gallis, Michail A.; Piekos, Edward Stanley

    2006-10-01T23:59:59.000Z

    In many direct simulation Monte Carlo (DSMC) simulations, the majority of computation time is consumed after the flowfield reaches a steady state. This situation occurs when the desired output quantities are small compared to the background fluctuations. For example, gas flows in many microelectromechanical systems (MEMS) have mean speeds more than two orders of magnitude smaller than the thermal speeds of the molecules themselves. The current solution to this problem is to collect sufficient samples to achieve the desired resolution. This can be an arduous process because the error is inversely proportional to the square root of the number of samples so we must, for example, quadruple the samples to cut the error in half. This work is intended to improve this situation by employing more advanced techniques, from fields other than solely statistics, for determining the output quantities. Our strategy centers on exploiting information neglected by current techniques, which collect moments in each cell without regard to one another, values in neighboring cells, nor their evolution in time. Unlike many previous acceleration techniques that modify the method itself, the techniques examined in this work strictly post-process so they may be applied to any DSMC code without affecting its fidelity or generality. Many potential methods are drawn from successful applications in a diverse range of areas, from ultrasound imaging to financial market analysis. The most promising methods exploit relationships between variables in space, which always exist in DSMC due to the absence of shocks. Disparate techniques were shown to produce similar error reductions, suggesting that the results shown in this report may be typical of what is possible using these methods. Sample count reduction factors of approximately three to five were found to be typical, although factors exceeding ten were shown on some variables under some techniques.

  14. Linear Accelerator | Advanced Photon Source

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    photo below). Selective phasing of the electric field accelerates the electrons to 450 million volts (MeV). At 450 MeV, the electrons are relativistic: they are traveling at...

  15. The Sustainable Building-Accelerator 

    E-Print Network [OSTI]

    Maassen, W.H.

    2011-01-01T23:59:59.000Z

    stages to generate optimal design solutions. The ''Sustainable Building - Accelerator'' supports stakeholders to decide on sustainable solutions by giving them cost and benefit information of design solutions. This information provides them...

  16. Israel Careers ACCELERATE YOUR FUTURE

    E-Print Network [OSTI]

    Rimon, Elon

    Lithography Control products within the product lifecycle process including defining requirements, settingIsrael Careers ACCELERATE YOUR FUTURE Product Marketing Manager Job Description: Product Marketing Manager at the Optical Metrology Division is responsible for product strategy and customer interface

  17. Sequentially pulsed traveling wave accelerator

    DOE Patents [OSTI]

    Caporaso, George J. (Livermore, CA); Nelson, Scott D. (Patterson, CA); Poole, Brian R. (Tracy, CA)

    2009-08-18T23:59:59.000Z

    A sequentially pulsed traveling wave compact accelerator having two or more pulse forming lines each with a switch for producing a short acceleration pulse along a short length of a beam tube, and a trigger mechanism for sequentially triggering the switches so that a traveling axial electric field is produced along the beam tube in synchronism with an axially traversing pulsed beam of charged particles to serially impart energy to the particle beam.

  18. BRIEF HISTORY OF FFAG ACCELERATORS.

    SciTech Connect (OSTI)

    RUGGIERO, A.

    2006-12-04T23:59:59.000Z

    Colleagues of mine have asked me few times why we have today so much interest in Fixed-Field Alternating-Gradient (FFAG) accelerators when these were invented a long time ago, and have always been ignored since then. I try here to give a reply with a short history of FFAG accelerators, at least as I know it. I take also the opportunity to clarify few definitions.

  19. Accelerating universes driven by bulk particles

    SciTech Connect (OSTI)

    Brito, F.A. [Departamento de Fisica, Universidade Federal de Campina Grande, 58109-970 Campina Grande, Paraiba (Brazil); Cruz, F.F.; Oliveira, J.F.N. [Departamento de Matematica, Universidade Regional do Cariri, 63040-000 Juazeiro do Norte, Ceara (Brazil)

    2005-04-15T23:59:59.000Z

    We consider our universe as a 3d domain wall embedded in a 5d dimensional Minkowski space-time. We address the problem of inflation and late time acceleration driven by bulk particles colliding with the 3d domain wall. The expansion of our universe is mainly related to these bulk particles. Since our universe tends to be permeated by a large number of isolated structures, as temperature diminishes with the expansion, we model our universe with a 3d domain wall with increasing internal structures. These structures could be unstable 2d domain walls evolving to fermi-balls which are candidates to cold dark matter. The momentum transfer of bulk particles colliding with the 3d domain wall is related to the reflection coefficient. We show a nontrivial dependence of the reflection coefficient with the number of internal dark matter structures inside the 3d domain wall. As the population of such structures increases the velocity of the domain wall expansion also increases. The expansion is exponential at early times and polynomial at late times. We connect this picture with string/M-theory by considering BPS 3d domain walls with structures which can appear through the bosonic sector of a five-dimensional supergravity theory.

  20. Beam-driven acceleration in ultra-dense plasma media

    SciTech Connect (OSTI)

    Shin, Young-Min [Fermi National Accelerator Laboratory, Batavia, IL (United States)

    2014-09-15T23:59:59.000Z

    Accelerating parameters of beam-driven wakefield acceleration in an extremely dense plasma column has been analyzed with the dynamic framed particle-in-cell plasma simulator, and compared with analytic calculations. In the model, a witness beam undergoes a TeV/m scale alternating potential gradient excited by a micro-bunched drive beam in a 1025 m-3 and 1.6 x 1028 m-3 plasma column. The acceleration gradient, energy gain, and transformer ratio have been extensively studied in quasi-linear, linear-, and blowout-regimes. The simulation analysis indicated that in the beam-driven acceleration system a hollow plasma channel offers 20 % higher acceleration gradient by enlarging the channel radius (r) from 0.2 ?p to 0.6 ?p in a blowout regime. This paper suggests a feasibility of TeV/m scale acceleration with a hollow crystalline structure (e.g. nanotubes) of high electron plasma density.

  1. Beam-driven acceleration in ultra-dense plasma media

    SciTech Connect (OSTI)

    Shin, Young-Min [Department of Physics, Northern Illinois University, Dekalb, Illinois 60115 (United States); Accelerator Physics Center (APC), Fermi National Accelerator Laboratory (FNAL), Batavia, Illinois 60510 (United States)

    2014-09-15T23:59:59.000Z

    Accelerating parameters of beam-driven wakefield acceleration in an extremely dense plasma column has been analyzed with the dynamic framed particle-in-cell plasma simulator, and compared with analytic calculations. In the model, a witness beam undergoes a TeV/m scale alternating potential gradient excited by a micro-bunched drive beam in a 10{sup 25?}m{sup ?3} and 1.6?×?10{sup 28?}m{sup ?3} plasma column. The acceleration gradient, energy gain, and transformer ratio have been extensively studied in quasi-linear, linear-, and blowout-regimes. The simulation analysis indicated that in the beam-driven acceleration system a hollow plasma channel offers ?20% higher acceleration gradient by enlarging the channel radius (r) from 0.2 ?{sub p} to 0.6 ?{sub p} in a blowout regime. This paper suggests a feasibility of TeV/m scale acceleration with a hollow crystalline structure (e.g., nanotubes) of high electron plasma density.

  2. Microwaves and particle accelerators: a fundamental link

    SciTech Connect (OSTI)

    Chattopadhyay, Swapan [Universities of Lancaster, Liverpool and Manchester and Cockcroft Institute, Cheshire (United Kingdom)

    2011-07-01T23:59:59.000Z

    John Cockcroft's splitting of the atom and Ernest Lawrence's invention of the cyclotron in the first half of the twentieth century ushered in the grand era of ever higher energy particle accelerators to probe deeper into matter. It also forged a link, bonding scientific discovery with technological innovation that continues today in the twenty first century. The development of radar and high power vacuum electronics, especially microwave power tubes like the magnetrons and the klystrons in the pre-second world war era, was instrumental in the rapid development of circular and linear charged particle accelerators in the second half of the twentieth century. We had harnessed the powerful microwave radio-frequency sources from few tens of MHz to up to 90 GHz spanning L-band to W-band frequencies. Simultaneously in the second half of the twentieth century, lasers began to offer very first opportunities of controlling charged particles at smaller resolutions on the scale of wavelengths of visible light. We also witnessed in this period the emergence of the photon and neutron sciences driven by accelerators built-by-design producing tailored and ultra-bright pulses of bright photons and neutrons to probe structure and function of matter from aggregate to individual molecular and atomic scales in unexplored territories in material and life sciences. As we enter the twenty first century, the race for ever higher energies, brightness and luminosity to probe atto-metric and atto-second domains of the ultra-small structures and ultra-fast processes continues. These developments depend crucially on yet further advancements in the production and control of high power and high frequency microwaves and light sources, often intricately coupled in their operation to the high energy beams themselves. We give a glimpse of the recent developments and innovations in the electromagnetic production and control of charged particle beams in the service of science and society. (author)

  3. Effects of pulsed-power loads upon an electric power grid

    SciTech Connect (OSTI)

    Smolleck, H.A.; Ranade, S.J.; Prasad, N.R. (New Mexico State Univ., Las Cruces, NM (USA). Dept. of Electrical and Computer Engineering); Velasco, R.O. (Los Alamos National Lab., NM (USA))

    1990-01-01T23:59:59.000Z

    Certain proposed particle-accelerator and laser experiments, and other devices related to fusion research, require multi-megawatt, repetitive power pulses, often at low (subsynchronous) frequency. While some power-delivery technologies call for a certain degree of buffering of the utility demand using capacitive, inductive, or inertial energy storage, considerations have also been made for serving such loads directly from the line. In either case, such pulsed loads represent non-traditional applications from the utility's perspective which, in certain cases, can have significant design and operational implications. This paper outlines an approach to the analysis of the effects of such loads upon the electric power grid using existing analysis techniques. The impacts studied include busvoltage flicker, transient and dynamic stability, and torsional excitation. The impact of a particular pulsed load is examined and illustrated for the power network serving the Los Alamos National Laboratory. 19 refs., 13 figs.

  4. Multimode Analysis of the Hollow Plasma Channel Wakefield Accelerator C. B. Schroeder,1

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    by resonant excitation [1]. In conventional accelerators, the size of these accel- erating fields is limited particle beam. For the laser wakefield accelerator one of the most se- vere limitations is the weakening- neous plasma. These properties make it well suited as a structure for both particle beam wakefield

  5. Particle Beam Stability in the Hollow Plasma Channel Wake Field Accelerator

    E-Print Network [OSTI]

    Wurtele, Jonathan

    Particle Beam Stability in the Hollow Plasma Channel Wake Field Accelerator Carl B. Schroeder1 structure is the transverse instability of the particle beam. INTRODUCTION Plasma-based accelerators have. The electromagnetic wake field response of a hollow plasma channel to a driver (laser or charged particle beam

  6. Dynamic Loading of Polycrystalline Shape Memory Alloy Rods

    E-Print Network [OSTI]

    in a cylindrical SMA rod in- duced by an impact loading is considered. Some applications of this model problem. Examples include joints that connect the hull of an underwater vehicle with its internal structure, tank armor, cargo con- tainers, etc. Another promising field of applications includes various active

  7. ORIGINAL ARTICLE Frictional systems subjected to oscillating loads

    E-Print Network [OSTI]

    Barber, James R.

    ORIGINAL ARTICLE Frictional systems subjected to oscillating loads J. R. Barber Received: 3 and a generalized Hertzian contact problem with friction. Keywords Coulomb friction Á Shakedown Á Damping Á of appropriate interaction laws for use in the analysis of masonry structures [1] and for the discrete element

  8. Response of Lithium Polymer Batteries to Mechanical Loading

    E-Print Network [OSTI]

    Petta, Jason

    with graphite. · Two layers of polymer separator with electrolyte. #12;Lithium Polymer Battery Structure Cu strain of the battery. #12;Anode - Graphite Crushed Uncrushed #12;Cathode ­ LiCoO2 Crushed Uncrushed #12Response of Lithium Polymer Batteries to Mechanical Loading Karl Suabedissen1, Christina Peabody2

  9. Inhomogeneous Cosmology, Inflation and Late-Time Accelerating Universe

    E-Print Network [OSTI]

    J. W. Moffat

    2007-05-30T23:59:59.000Z

    An exact inhomogeneous solution of Einstein's field equations is shown to be able to inflate in a non-uniform way in the early universe and explain anomalies in the WMAP power spectrum data. It is also possible for the model to explain the accelerated expansion of the universe by late-time inhomogeneous structure.

  10. MODELING AND CONTROL OF THERMOSTATICALLY CONTROLLED LOADS

    E-Print Network [OSTI]

    Hiskens, Ian A.

    controlled loads (TCLs) has demonstrated that such load following is feasible, but analyt- ical models) is well matched to the role of load following. Re- search into the behavior of TCLs began with the work was then employed in a minimum variance control law to demonstrate the load following capability of a population

  11. Flow Duration Curve Load Duration Curve

    E-Print Network [OSTI]

    #12;Flow Duration Curve Load Duration Curve #12;1. Develop Flow Duration Curve 2. Estimate load given flow and concentration data--select appropriate conversion factors 3. Develop Load Duration Curve 4. Plot observed data with Load Duration Curve #12;What are they? How do you make one? #12;Describes

  12. Flow Duration Curve Load Duration Curve

    E-Print Network [OSTI]

    Flow Duration Curve Load Duration Curve 1. Develop Flow Duration Curve 2. Estimate load given flow and concentration data--select appropriate conversion factors 3. Develop Load Duration Curve 4. Plot observed data with Load Duration Curve What are they? How do you make one? Describes the percent of time a flow rate

  13. Analysis of the Thermal Loads on the KSTAR Cryogenic System

    SciTech Connect (OSTI)

    Kim, Y.S.; Oh, Y.K.; Kim, W.C.; Park, Y.M.; Lee, Y.J.; Jin, S.B.; Sa, J.W.; Choi, C.H.; Cho, K.W.; Bak, J.S.; Lee, G.S. [Korea Basic Science Institute, Yusung-Ku, Daejeon 305-806 (Korea, Republic of)

    2004-06-23T23:59:59.000Z

    A large-scale helium refrigeration system is one of the key components for the KSTAR (Korea Superconducting Tokamak Advanced Research) device. In the design of the refrigeration system, an estimation of the thermal loads on the cold mass is an important issue according to the operation scenario. The cold mass of the KSTAR device is about 250 tons including 30 superconducting (SC) coils and the magnet structure. In addition to the static thermal loads, pulsed thermal loads to the refrigeration system have been considered in the operation stage. The main pulsed thermal loads on magnet system are AC losses in the SC coils and eddy current losses in the magnet structure that depend on the magnetic field variation rate. The nuclear radiation loss due to plasma pulse operation is also considered. The designed cooling capacity of the refrigeration system is estimated to be about 9 kW at 4.5 K isothermal. In this paper, calculation of the various kinds of thermal loads on KSTAR cryogenic system and design of the large-scale helium refrigeration system are presented.

  14. Microwave power coupler for a superconducting multiple-cell cavity for accelerator application and its testing procedures

    SciTech Connect (OSTI)

    Li, Jianjian; /IIT, Chicago

    2008-12-01T23:59:59.000Z

    Superconducting cavity resonators offer the advantage of high field intensity for a given input power, making them an attractive contender for particle accelerator applications. Power coupling into a superconducting cavity employed in a particle accelerator requires unique provisions to maintain high vacuum and cryogenic temperature on the cavity side, while operating with ambient conditions on the source side. Components introduced to fulfill mechanical requirements must show negligible obstruction of the propagation of the microwave with absence of critical locations that may give rise to electron multipaction, leading to a multiple section design, instead of an aperture, a probe, or a loop structure as found in conventional cavities. A coaxial power coupler for a superconducting multiple-cell cavity at 3.9 GHz has been developed. The cavity is intended to be employed as an accelerator to provide enhanced electron beam quality in a free-electron laser in Hamburg (FLASH) user facility. The design of the coupler called for two windows to sustain high vacuum in the cavity and two bellows to accommodate mechanical dimensional changes resulting from cryogenics. Suppression of multipacting was accomplished by the choice of conductor dimensions and materials with low second yield coefficients. Prior to integration with the cavity, the coupler was tested for intrinsic properties in a back-to-back configuration and conditioned for high-power operation with increasing power input. Maximum incident power was measured to be 61 kW. When integrated with the superconducting cavity, a loaded quality factor of 9 x 10{sup 5} was measured by transient method. Coupler return loss and insertion loss were estimated to be around -21 dB and -0.2 dB, respectively.

  15. RADIO EMISSION OF SOLAR FLARE PARTICLE ACCELERATION

    E-Print Network [OSTI]

    RADIO EMISSION OF SOLAR FLARE PARTICLE ACCELERATION A. O. Benz Abstract The solar corona is a very be considered as a particle accelerator. The free mobility of charged particles in a dilute plasma to accelerate particles in resonance. From a plasma physics point of view, acceleration is not surprising

  16. Investigation of residential central air conditioning load shapes in NEMS

    SciTech Connect (OSTI)

    Hamachi LaCommare, Kristina; Marnay, Chris; Gumerman, Etan; Chan, Peter; Rosenquist, Greg; Osborn, Julie

    2002-05-01T23:59:59.000Z

    This memo explains what Berkeley Lab has learned about how the residential central air-conditioning (CAC) end use is represented in the National Energy Modeling System (NEMS). NEMS is an energy model maintained by the Energy Information Administration (EIA) that is routinely used in analysis of energy efficiency standards for residential appliances. As part of analyzing utility and environmental impacts related to the federal rulemaking for residential CAC, lower-than-expected peak utility results prompted Berkeley Lab to investigate the input load shapes that characterize the peaky CAC end use and the submodule that treats load demand response. Investigations enabled a through understanding of the methodology by which hourly load profiles are input to the model and how the model is structured to respond to peak demand. Notably, it was discovered that NEMS was using an October-peaking load shape to represent residential space cooling, which suppressed peak effects to levels lower than expected. An apparent scaling down of the annual load within the load-demand submodule was found, another significant suppressor of the peak impacts. EIA promptly responded to Berkeley Lab's discoveries by updating numerous load shapes for the AEO2002 version of NEMS; EIA is still studying the scaling issue. As a result of this work, it was concluded that Berkeley Lab's customary end-use decrement approach was the most defensible way for Berkeley Lab to perform the recent CAC utility impact analysis. This approach was applied in conjunction with the updated AEO2002 load shapes to perform last year's published rulemaking analysis. Berkeley Lab experimented with several alternative approaches, including modifying the CAC efficiency level, but determined that these did not sufficiently improve the robustness of the method or results to warrant their implementation. Work in this area will continue in preparation for upcoming rulemakings for the other peak coincident end uses, commercial air conditioning and distribution transformers.

  17. Tested by Fire - How two recent Wildfires affected Accelerator Operations at LANL

    SciTech Connect (OSTI)

    Spickermann, Thomas [Los Alamos National Laboratory

    2012-08-01T23:59:59.000Z

    In a little more than a decade two large wild fires threatened Los Alamos and impacted accelerator operations at LANL. In 2000 the Cerro Grande Fire destroyed hundreds of homes, as well as structures and equipment at the DARHT facility. The DARHT accelerators were safe in a fire-proof building. In 2011 the Las Conchas Fire burned about 630 square kilometers (250 square miles) and came dangerously close to Los Alamos/LANL. LANSCE accelerator operations Lessons Learned during Las Conchas fire: (1) Develop a plan to efficiently shut down the accelerator on short notice; (2) Establish clear lines of communication in emergency situations; and (3) Plan recovery and keep squirrels out.

  18. Plasmonic Meta-Surface for Efficient Ultra-Short Pulse Laser-Driven Particle Acceleration

    E-Print Network [OSTI]

    Bar-Lev, Doron

    2014-01-01T23:59:59.000Z

    A laser-driven particle accelerator based on plasmonic nano-antennas is proposed and analyzed. The concept utilizes the enhancement and localization of the electric field by nano-antennas to maximize the acceleration gradient and to overcome potential metallic losses. The structure is optimized for accelerating relativistic particles using a femto-second laser source operating at 800nm, and is shown to support the bandwidth of ultra-short laser pulses (up to 16fsec) while providing a high acceleration gradient potentially reaching 11.6GV/m.

  19. Determining equivalent damage loading for full-scale wind turbine blade fatigue tests

    SciTech Connect (OSTI)

    Freebury, G.; Musial, W.

    2000-03-13T23:59:59.000Z

    This paper describes a simplified method for converting wind turbine rotor design loads into equivalent-damage, constant-amplitude loads and load ratios for both flap and lead-lag directions. It is an iterative method that was developed at the National Renewable Energy Laboratory (NREL) using Palmgren-Miner's linear damage principles. The general method is unique because it does not presume that any information about the materials or blade structural properties is precisely known. According to this method, the loads are never converted to stresses. Instead, a family of M-N curves (moment vs. cycles) is defined with reasonable boundaries for load-amplitude and slope. An optimization program iterates and converges on the constant amplitude test load and load ratio that minimizes the sensitivity to the range of M-N curves for each blade section. The authors constrained the general method to match the NedWind 25 design condition for the Standards, Measurements, and Testing (SMT) blade testing pro gram. SMT participants agreed to use the fixed S-N slope of m = 10 from the original design to produce consistent test-loads among the laboratories. Unconstrained, the general method suggests that slightly higher test loads should be used for the NedWind 25 blade design spectrum. NedWind 25 blade test loads were computed for lead-lag and flap under single-axis and two-axis loading.

  20. Accelerator and electrodynamics capability review

    SciTech Connect (OSTI)

    Jones, Kevin W [Los Alamos National Laboratory

    2010-01-01T23:59:59.000Z

    Los Alamos National Laboratory (LANL) uses capability reviews to assess the science, technology and engineering (STE) quality and institutional integration and to advise Laboratory Management on the current and future health of the STE. Capability reviews address the STE integration that LANL uses to meet mission requirements. The Capability Review Committees serve a dual role of providing assessment of the Laboratory's technical contributions and integration towards its missions and providing advice to Laboratory Management. The assessments and advice are documented in reports prepared by the Capability Review Committees that are delivered to the Director and to the Principal Associate Director for Science, Technology and Engineering (PADSTE). Laboratory Management will use this report for STE assessment and planning. LANL has defined fifteen STE capabilities. Electrodynamics and Accelerators is one of the seven STE capabilities that LANL Management (Director, PADSTE, technical Associate Directors) has identified for review in Fiscal Year (FY) 2010. Accelerators and electrodynamics at LANL comprise a blend of large-scale facilities and innovative small-scale research with a growing focus on national security applications. This review is organized into five topical areas: (1) Free Electron Lasers; (2) Linear Accelerator Science and Technology; (3) Advanced Electromagnetics; (4) Next Generation Accelerator Concepts; and (5) National Security Accelerator Applications. The focus is on innovative technology with an emphasis on applications relevant to Laboratory mission. The role of Laboratory Directed Research and Development (LDRD) in support of accelerators/electrodynamics will be discussed. The review provides an opportunity for interaction with early career staff. Program sponsors and customers will provide their input on the value of the accelerator and electrodynamics capability to the Laboratory mission.

  1. Ultra-high vacuum photoelectron linear accelerator

    DOE Patents [OSTI]

    Yu, David U.L.; Luo, Yan

    2013-07-16T23:59:59.000Z

    An rf linear accelerator for producing an electron beam. The outer wall of the rf cavity of said linear accelerator being perforated to allow gas inside said rf cavity to flow to a pressure chamber surrounding said rf cavity and having means of ultra high vacuum pumping of the cathode of said rf linear accelerator. Said rf linear accelerator is used to accelerate polarized or unpolarized electrons produced by a photocathode, or to accelerate thermally heated electrons produced by a thermionic cathode, or to accelerate rf heated field emission electrons produced by a field emission cathode.

  2. Based Accelerators Gennady Shvets

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041cloth DocumentationProductsAlternativeOperationalAugustDecade5-F,INITIAL JohnEAdvanced Structure -

  3. Hazard consistent structural demands and in-structure design response spectra

    SciTech Connect (OSTI)

    Houston, Thomas W [Los Alamos National Laboratory; Costantino, Michael C [Los Alamos National Laboratory; Costantino, Carl J [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    Current analysis methodology for the Soil Structure Interaction (SSI) analysis of nuclear facilities is specified in ASCE Standard 4. This methodology is based on the use of deterministic procedures with the intention that enough conservatism is included in the specified procedures to achieve an 80% probability of non-exceedance in the computed response of a Structure, System. or Component for given a mean seismic design input. Recently developed standards are aimed at achieving performance-based, risk consistent seismic designs that meet specified target performance goals. These design approaches rely upon accurately characterizing the probability (hazard) level of system demands due to seismic loads consistent with Probabilistic Seismic Hazard Analyses. This paper examines the adequacy of the deterministic SSI procedures described in ASCE 4-98 to achieve an 80th percentile of Non-Exceedance Probability (NEP) in structural demand, given a mean seismic input motion. The study demonstrates that the deterministic procedures provide computed in-structure response spectra that are near or greater than the target 80th percentile NEP for site profiles other than those resulting in high levels of radiation damping. The deterministic procedures do not appear to be as robust in predicting peak accelerations, which correlate to structural demands within the structure.

  4. Surface plasmon routing in dielectric-loaded surface plasmon polariton waveguides

    E-Print Network [OSTI]

    Grandidier, Jonathan

    Surface plasmon routing in dielectric-loaded surface plasmon polariton waveguides J. Grandidier, S ABSTRACT Waveguiding by dielectric-loaded surface plasmon-polaritons (DLSPP) structures are numerically waveguide parameters such as width and thickness on the properties of the surface plasmon guided modes

  5. American Institute of Aeronautics and Astronautics An Experimental Investigation on Dynamic Wind Loads Acting on a

    E-Print Network [OSTI]

    Hu, Hui

    of the wind turbine blades = air density I. Introduction he mechanical design of a wind turbine structure Loads Acting on a Wind Turbine Model in Atomspheric Boundary Layer Winds Wei Tian1 , Ahmet Ozbay2 An experimental study was conducted to investigate the dynamic wind loads acting on a wind turbine model sited

  6. Analytical and numerical methods for processing Hopkinson Bar Loaded Bending test on concrete: a comparative study

    E-Print Network [OSTI]

    Boyer, Edmond

    Analytical and numerical methods for processing Hopkinson Bar Loaded Bending test on concrete on dynamic characteristics of concrete. Various techniques have been used to test concretes at high strain for concrete structures subjected to dynamic loading such as explosions or im- pacts require information

  7. Damage and Damage Prediction for Wood Shearwalls Subjected to Simulated Earthquake Loads

    E-Print Network [OSTI]

    Gupta, Rakesh

    Damage and Damage Prediction for Wood Shearwalls Subjected to Simulated Earthquake Loads John W damaged resulting in large financial losses. Societal demands for damage-limiting design philosophies and better predict damage to woodframe structures. This paper examines damage to the lateral load carrying

  8. Mitigation of Fatigue Loads Using Individual Pitch Control of Wind Turbines Based on FAST

    E-Print Network [OSTI]

    Chen, Zhe

    Mitigation of Fatigue Loads Using Individual Pitch Control of Wind Turbines Based on FAST Yunqian University, China jiz@seu.edu.cn Abstract-With the increase of wind turbine dimension and capacity, the wind turbine structures are subjected to prominent loads and fatigue which would reduce the lifetime of wind

  9. Accelerator Physics Accelerators form the backbone of SLAC's on-site experimental program. Research at SLAC

    E-Print Network [OSTI]

    Wechsler, Risa H.

    #12;Accelerator Physics Accelerators form the backbone of SLAC's on-site experimental program. Research at SLAC is continually improving accelerators, both here and at other laboratories, and paving the way for a new generation of particle acceleration technology. SLAC's famous linear accelerator

  10. DC-like Phase Space Manipulation and Particle Acceleration Using Chirped AC Fields

    SciTech Connect (OSTI)

    P.F. Schmit and N.J. Fisch

    2009-06-17T23:59:59.000Z

    Waves in plasmas can accelerate particles that are resonant with the wave. A DC electric field also accelerates particles, but without a resonance discrimination, which makes the acceleration mechanism profoundly different. We investigate the effect on a Hamiltonian distribution of an accelerating potential waveform, which could, for example, represent the average ponderomotive effect of two counterpropagating electromagnetic waves. In particular, we examine the apparent DC-like time-asymptotic response of the distribution in regimes where the potential structure is accelerated adiabatically. A highly resonant population within the distribution is always present, and we characterize its nonadiabatic response during wave-particle resonance using an integral method in the noninertial reference frame moving with the wave. Finally, we show that in the limit of infinitely slow acceleration of the wave, these highly resonant particles disappear and the response

  11. Particle Acceleration in three dimensional Reconnection Regions: A New Test Particle Approach

    E-Print Network [OSTI]

    Rudiger Schopper; Guido T. Birk; Harald Lesch

    2001-06-29T23:59:59.000Z

    Magnetic Reconnection is an efficient and fast acceleration mechanism by means of direct electric field acceleration parallel to the magnetic field. Thus, acceleration of particles in reconnection regions is a very important topic in plasma astrophysics. This paper shows that the conventional analytical models and numerical test particle investigations can be misleading concerning the energy distribution of the accelerated particles, since they oversimplify the electric field structure by the assumption that the field is homogeneous. These investigations of the acceleration of charged test particles are extended by considering three-dimensional field configurations characterized by localized field-aligned electric fields. Moreover, effects of radiative losses are discussed. The comparison between homogeneous and inhomogeneous electric field acceleration in reconnection regions shows dramatic differences concerning both, the maximum particle energy and the form of the energy distribution.

  12. Modern theory of Fermi acceleration: a new challenge to plasma physics

    E-Print Network [OSTI]

    M. A. Malkov; P. H. Diamond

    2001-02-21T23:59:59.000Z

    One of the main features of astrophysical shocks is their ability to accelerate particles to extremely high energies. The leading acceleration mechanism, the diffusive shock acceleration is reviewed. It is demonstrated that its efficiency critically depends on the injection of thermal plasma into acceleration which takes place at the subshock of the collisionless shock structure that, in turn, can be significantly smoothed by energetic particles. Furthermore, their inhomogeneous distribution provides free energy for MHD turbulence regulating the subshock strength and injection rate. Moreover, the MHD turbulence confines particles to the shock front controlling their maximum energy and bootstrapping acceleration. Therefore, the study of the MHD turbulence in a compressive plasma flow near a shock is a key to understanding of the entire process. The calculation of the injection rate became part of the collisionless shock theory. It is argued that the further progress in diffusive shock acceleration theory is impossible without a significant advance in these two areas of plasma physics.

  13. Particle acceleration in thick parallel shocks with high compression ratio

    E-Print Network [OSTI]

    Joni J. P. Virtanen; Rami Vainio

    2005-06-06T23:59:59.000Z

    We report studies on first-order Fermi acceleration in parallel modified shock waves with a large scattering center compression ratio expected from turbulence transmission models. Using a Monte Carlo technique we have modeled particle acceleration in shocks with a velocity ranging from nonrelativistic to ultrarelativistic and a thickness extending from nearly steplike to very wide structures exceeding the particle diffusion length by orders of magnitude. The nonrelativistic diffusion approximation is found to be surprisingly accurate in predicting the spectral index of a thick shock with large compression ratio even in the cases involving relativistic shock speeds.

  14. PRB rail loadings shatter record

    SciTech Connect (OSTI)

    Buchsbaum, L.

    2008-09-15T23:59:59.000Z

    Rail transport of coal in the Powder River Basin has expanded, with a record 2,197 trains loaded in a month. Arch Coal's Thunder basin mining complex has expanded by literally bridging the joint line railway. The dry fork mine has also celebrated its safety achievements. 4 photos.

  15. Microstructure evolution during tensile loading histories of a polyurea

    SciTech Connect (OSTI)

    Rinaldi, R.G.; Boyce, M.C.; Weigand, S.J.; Londono, D.J.; Guise, M.W. (MIT); (NWU); (Dupont)

    2012-02-07T23:59:59.000Z

    The evolution in the hard/soft domain microstructure of an elastomeric-like polyurea during different tensile loading histories was studied using in situ small- and wide-angle X-ray scattering (SAXS/WAXS). The nonlinear stress-strain behavior is initially stiff with a rollover yield to a more compliant response; unloading is highly nonlinear showing substantial hysteresis while also exhibiting significant recovery. Reloading reveals a substantially more compliant 'softened' behavior and dramatically reduced hysteresis. WAXS peaks monitor characteristic dimensions of regular features within the hard domains; the peak location remains unchanged with tensile deformation indicating no separation of the internal structure within a domain, but the peak intensity becomes anisotropic with deformation evolving in a reversible manner consistent with orientation due to stretch. The SAXS profiles provide information between major hard domains. SAXS peaks are found to shift with tensile loading in a relatively affine manner up to a tensile true strain of {approx}0.4, which, using a Bragg reduction to aid interpretation, reveals an axial increase and a transverse decrease in interdomain spacings; this evolution is reversible for strains less than {approx}0.4. Increasing axial strain beyond a true strain of {approx}0.4 is accompanied by a dramatic, progressive, and irreversible reduction in axial Bragg spacing, indicating a breakdown in the hard domain aggregate network structure. A four-point pattern is seen to develop during stretching. The breakdown in networked structure during a first load cycle gives a new structure for subsequent load cycles, which is seen to evolve in a reversible manner for strains less than or equal to the prior maximum strain. However, for strains exceeding the prior maximum strain excursion, additional breakdown is found. These SAXS results show that a breakdown in the hard domain aggregate network structure is a governing mechanism for the large dissipation (hysteresis) loops of the first load cycle and are also responsible for the softened reloading response. The absence of structure breakdown during subsequent load cycles corresponds to the substantially reduced hysteresis loops as well as the stable softened behavior. DMA data on pristine and previously deformed samples show a more compliant storage modulus in the predeformed sample, supporting the softened cyclic stress-strain data and the structural breakdown observed in the SAXS; the loss modulus was unchanged with deformation, which correlates with the lossy features measured in DMA with time-dependent viscosity rather than losses due to structural breakdown.

  16. Numerical Verification of the Power Transfer and Wakefield Coupling in the CLIC Two-Beam Accelerator

    E-Print Network [OSTI]

    Candel, Arno; NG, C; Rawat, V; Schussman, G; Ko, K; Syratchev, I; Grudiev, A; Wuensch, W

    2011-01-01T23:59:59.000Z

    The Compact Linear Collider (CLIC) provides a path to a multi-TeV accelerator to explore the energy frontier of High Energy Physics. Its two-beam accelerator (TBA) concept envisions complex 3D structures, which must be modeled to high accuracy so that simulation results can be directly used to prepare CAD drawings for machining. The required simulations include not only the fundamental mode properties of the accelerating structures but also the Power Extraction and Transfer Structure (PETS), as well as the coupling between the two systems. Time-domain simulations will be performed to understand pulse formation, wakefield damping, fundamental power transfer and wakefield coupling in these structures. Applying SLAC’s parallel finite element code suite, these large-scale problems will be solved on some of the largest supercomputers available. The results will help to identify potential issues and provide new insights on the design, leading to further improvements on the novel two-beam accelerator scheme.

  17. Superconducting Magnets for Particle Accelerators

    E-Print Network [OSTI]

    Rossi, L

    2012-01-01T23:59:59.000Z

    Superconductivity has been the most influential technology in the field of accelerators in the last 30 years. Since the commissioning of the Tevatron, which demonstrated the use and operability of superconductivity on a large scale, superconducting magnets and rf cavities have been at the heart of all new large accelerators. Superconducting magnets have been the invariable choice for large colliders, as well as cyclotrons and large synchrotrons. In spite of the long history of success, superconductivity remains a difficult technology, requires adequate R&D and suitable preparation, and has a relatively high cost. Hence, it is not surprising that the development has also been marked by a few setbacks. This article is a review of the main superconducting accelerator magnet projects; it highlights the main characteristics and main achievements, and gives a perspective on the development of superconducting magnets for the future generation of very high energy colliders.

  18. Virtual gap dielectric wall accelerator

    DOE Patents [OSTI]

    Caporaso, George James; Chen, Yu-Jiuan; Nelson, Scott; Sullivan, Jim; Hawkins, Steven A

    2013-11-05T23:59:59.000Z

    A virtual, moving accelerating gap is formed along an insulating tube in a dielectric wall accelerator (DWA) by locally controlling the conductivity of the tube. Localized voltage concentration is thus achieved by sequential activation of a variable resistive tube or stalk down the axis of an inductive voltage adder, producing a "virtual" traveling wave along the tube. The tube conductivity can be controlled at a desired location, which can be moved at a desired rate, by light illumination, or by photoconductive switches, or by other means. As a result, an impressed voltage along the tube appears predominantly over a local region, the virtual gap. By making the length of the tube large in comparison to the virtual gap length, the effective gain of the accelerator can be made very large.

  19. Symposium on accelerator mass spectrometry

    SciTech Connect (OSTI)

    None

    1981-01-01T23:59:59.000Z

    The area of accelerator mass spectrometry has expanded considerably over the past few years and established itself as an independent and interdisciplinary research field. Three years have passed since the first meeting was held at Rochester. A Symposium on Accelerator Mass Spectrometry was held at Argonne on May 11-13, 1981. In attendance were 96 scientists of whom 26 were from outside the United States. The present proceedings document the program and excitement of the field. Papers are arranged according to the original program. A few papers not presented at the meeting have been added to complete the information on the status of accelerator mass spectrometry. Individual papers were prepared separately for the data base.

  20. Independent review of estimated load reductions for PJM's small customer load response pilot project

    E-Print Network [OSTI]

    Heffner, G.; Moezzi, M.; Goldman, C.

    2004-01-01T23:59:59.000Z

    of Estimated Load Reductions for PJM’s Small Customer Loadof Estimated Load Reductions for PJM’s Small Customer LoadResponse Pilot Project Prepared for PJM Interconnection, LLC

  1. Efficient control of accelerator maps

    E-Print Network [OSTI]

    Jehan Boreux; Timoteo Carletti; Charalampos Skokos; Yannis Papaphilippou; Michel Vittot

    2011-09-21T23:59:59.000Z

    Recently, the Hamiltonian Control Theory was used in [Boreux et al.] to increase the dynamic aperture of a ring particle accelerator having a localized thin sextupole magnet. In this letter, these results are extended by proving that a simplified version of the obtained general control term leads to significant improvements of the dynamic aperture of the uncontrolled model. In addition, the dynamics of flat beams based on the same accelerator model can be significantly improved by a reduced controlled term applied in only 1 degree of freedom.

  2. Accelerated dynamics simulations of nanotubes.

    SciTech Connect (OSTI)

    Uberuaga, B. P. (Blas Pedro); Stuart, S. J. (Steve J.); Voter, A. F.

    2002-01-01T23:59:59.000Z

    We report on the application of accelerated dynamics techniques to the study of carbon nanotubes. We have used the parallel replica method and temperature accelerated dynamics simulations are currently in progress. In the parallel replica study, we have stretched tubes at a rate significantly lower than that used in previous studies. In these preliminary results, we find that there are qualitative differences in the rupture of the nanotubes at different temperatures. We plan on extending this investigation to include nanotubes of various chiralities. We also plan on exploring unique geometries of nanotubes.

  3. Weak-Chaos Ratchet Accelerator

    E-Print Network [OSTI]

    Itzhack Dana; Vladislav B. Roitberg

    2012-05-28T23:59:59.000Z

    Classical Hamiltonian systems with a mixed phase space and some asymmetry may exhibit chaotic ratchet effects. The most significant such effect is a directed momentum current or acceleration. In known model systems, this effect may arise only for sufficiently strong chaos. In this paper, a Hamiltonian ratchet accelerator is introduced, featuring a momentum current for arbitrarily weak chaos. The system is a realistic, generalized kicked rotor and is exactly solvable to some extent, leading to analytical expressions for the momentum current. While this current arises also for relatively strong chaos, the maximal current is shown to occur, at least in one case, precisely in a limit of arbitrarily weak chaos.

  4. Centralized digital control of accelerators

    SciTech Connect (OSTI)

    Melen, R.E.

    1983-09-01T23:59:59.000Z

    In contrasting the title of this paper with a second paper to be presented at this conference entitled Distributed Digital Control of Accelerators, a potential reader might be led to believe that this paper will focus on systems whose computing intelligence is centered in one or more computers in a centralized location. Instead, this paper will describe the architectural evolution of SLAC's computer based accelerator control systems with respect to the distribution of their intelligence. However, the use of the word centralized in the title is appropriate because these systems are based on the use of centralized large and computationally powerful processors that are typically supported by networks of smaller distributed processors.

  5. Electron Cloud Effects in Accelerators

    SciTech Connect (OSTI)

    Furman, M.A.

    2012-11-30T23:59:59.000Z

    Abstract We present a brief summary of various aspects of the electron-cloud effect (ECE) in accelerators. For further details, the reader is encouraged to refer to the proceedings of many prior workshops, either dedicated to EC or with significant EC contents, including the entire ?ECLOUD? series [1?22]. In addition, the proceedings of the various flavors of Particle Accelerator Conferences [23] contain a large number of EC-related publications. The ICFA Beam Dynamics Newsletter series [24] contains one dedicated issue, and several occasional articles, on EC. An extensive reference database is the LHC website on EC [25].

  6. COMPASS, the COMmunity Petascale project for Accelerator Science and Simulation, a broad computational accelerator physics

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    COMPASS, the COMmunity Petascale project for Accelerator Science and Simulation, a broad at Lawrence Livermore National Laboratory. #12;COMPASS, the COMmunity Petascale project for Accelerator for materials studies. COMPASS, the Community Petascale Project for Accelerator Science and Simulation

  7. FY 93 Thermal Loading Systems Study Final Report

    SciTech Connect (OSTI)

    S.F. Saterlie

    1994-08-29T23:59:59.000Z

    The objective of the Mined Geologic Disposal System (MGDS) Thermal Loading Systems Study being conducted by the is to identify a thermal strategy that will meet the performance requirements for waste isolation and will be safe and licensable. Specifically, both postclosure and preclosure performance standards must be met by the thermal loading strategy ultimately selected. In addition cost and schedule constraints must be considered. The Systems Engineering approach requires structured, detailed analyses that will ultimately provide the technical basis for the development, integration, and evaluation of the overall system, not just a subelement of that system. It is also necessary that the systems study construct options from within the range that are allowed within the current legislative and programmatic framework. For example the total amount of fuel that can legally be emplaced is no more than 70,000 metric tons of uranium (MTU) which is composed of 63,000 MTU spent fuel and 7,000 MTU of defense high level waste. It is the intent of this study to begin the structured development of the basis for a thermal loading decision. However, it is recognized that to be able to make a final decision on thermal loading will require underground data on the effects of heating as well as a suite of ''validated'' models. It will be some time before these data and models are available to the program. Developing a final, thermal loading decision will, therefore, be an iterative process. In the interim, the objective of the thermal loading systems study has been to utilize the information available to assess the impact of thermal loading. Where technical justification exists, recommendations to narrow the range of thermal loading options can be made. Additionally, recommendations as to the type of testing and accuracy of the testing needed to establish the requisite information will be made. A constraint on the ability of the study to select an option stems from the lack of primary hard data, uncertainties in derived data, unsubstantiated models, and the inability to fully consider simultaneously coupled processes. As such, the study must rely on idealized models and available data to compare the thermal loading options. This report presents the findings of the FY 1993 MGDS Thermal Loading Systems Study. The objectives of the study were to: (1) if justified, place bounds on the thermal loading which would establish the loading that is ''too hot''; (2) ''grade'' or evaluate the performance as a function of thermal loading of the potential repository to contain high level spent nuclear fuel against performance criteria; (3) evaluate the performance of the various options with respect to cost, safety, and operability; and (4) recommend the additional types of tests and/or analyses to be conducted to provide the necessary information for a thermal loading selection.

  8. Effect of Axial Loading on Quench Performance in Nb3Sn Magnets

    SciTech Connect (OSTI)

    Ambrosio, G.; Bordini, B.; Caspi, S.; Dietderich, D.R.; Felice, H.; Hafalia, A.R.; Hannaford, C.R.; Lizarazo, J.; Lietzke, A.F.; McInturff, A.D.; Sabbi, G.L.; DiMarco, J.D.; Tartaglia, M.; Vedrice, P.; Ferracin, P.

    2008-06-01T23:59:59.000Z

    A series of tests has been performed at Lawrence Berkeley National Laboratory (LBNL) and Fermi National Accelerator Laboratory (FNAL) with the goal of assessing the influence of coil axial pre-load on Nb{sub 3}Sn magnet training. The tests involved two subscale Nb{sub 3}Sn magnets: SQ02, a quadrupole magnet fabricated as part of the US LHC Accelerator Research Program (LARP), and SD01, a dipole magnet developed in collaboration between CEA/Saclay and LBNL. Both magnets used similar Nb{sub 3}Sn flat racetrack coils from LBNL Subscale Magnet Program, and implemented an axial support system composed of stainless steel end-plates and aluminum rods. The system was designed to withstand full longitudinal electro-magnetic forces and provide controllable preloads. Quench performances, training, and quench locations have been recorded in various axial loading conditions. Test results are reported.

  9. Dynamic failure prediction of cross-rolled beryllium sheets subjected to vibration loads

    E-Print Network [OSTI]

    Serna, Oscar R.

    1996-01-01T23:59:59.000Z

    The principal objective of this investigation is to develop and verify a numerical method for prediction of failure for cross-rolled beryllium sheet structures that are subjected to vibration loads. To this end, complementary laboratory experiments...

  10. An evaluation of finite element models of stiffened plates subjected to impulsive loading

    E-Print Network [OSTI]

    Pedatzur, Omri

    2004-01-01T23:59:59.000Z

    Different finite element models are evaluated for two very common structures, a cantilever beam and a stiffened plate, subjected to impulsive loading. For the cantilever beam case, the finite element models are one, two ...

  11. Active load control techniques for wind turbines.

    SciTech Connect (OSTI)

    van Dam, C.P. (University of California, Davis, CA); Berg, Dale E.; Johnson, Scott J. (University of California, Davis, CA)

    2008-07-01T23:59:59.000Z

    This report provides an overview on the current state of wind turbine control and introduces a number of active techniques that could be potentially used for control of wind turbine blades. The focus is on research regarding active flow control (AFC) as it applies to wind turbine performance and loads. The techniques and concepts described here are often described as 'smart structures' or 'smart rotor control'. This field is rapidly growing and there are numerous concepts currently being investigated around the world; some concepts already are focused on the wind energy industry and others are intended for use in other fields, but have the potential for wind turbine control. An AFC system can be broken into three categories: controls and sensors, actuators and devices, and the flow phenomena. This report focuses on the research involved with the actuators and devices and the generated flow phenomena caused by each device.

  12. Plasma Wakefield Acceleration and FACET - Facilities for Accelerator Science and Experimental Test Beams at SLAC

    ScienceCinema (OSTI)

    Andrei Seryi

    2010-01-08T23:59:59.000Z

    Plasma wakefield acceleration is one of the most promising approaches to advancing accelerator technology. This approach offers a potential 1,000-fold or more increase in acceleration over a given distance, compared to existing accelerators.  FACET, enabled by the Recovery Act funds, will study plasma acceleration, using short, intense pulses of electrons and positrons. In this lecture, the physics of plasma acceleration and features of FACET will be presented.  

  13. Relativistic parsec-scale jets: I. Particle acceleration

    E-Print Network [OSTI]

    A. R. Beresnyak; Ya. N. Istomin; V. I. Pariev

    2003-03-05T23:59:59.000Z

    We develop a theory of particle acceleration inside relativistic rotating electron-positron force-free jets with spiral magnetic fields. We considered perturbation of the stationary magnetic field structure and found that acceleration takes place in the regions where the Alfven resonant condition with the eigenmodes in the jet is fulfilled, i.e. where the local Alfven speed is equal to the phase speed of an eigenmode. The acceleration mechanism is regular acceleration by the electric field of the electromagnetic wave, which is the eigenmode of the force-free cylindrical jet: particles drift out of the region of the large wave amplitude near the Alfven resonant surface and gain energy. Acceleration in the strong electric field near the Alfven resonance and synchrotron losses combine to form a power-law energy spectrum of ultra-relativistic electrons and positrons with index between 2 and 3 depending upon the initial energy of the injected particles. The power law distribution ranges from 10 MeV to 1000 MeV.

  14. Phase Stable Net Acceleration of Electrons From a Two-Stage Optical Accelerator

    SciTech Connect (OSTI)

    Sears, Christopher M.S.; /SLAC /Munich, Max Planck Inst. Quantenopt.; Colby, Eric; England, R.J.; Ischebeck, Rasmus; McGuinness, Christopher; Nelson, Janice; Noble, Robert; Siemann, Robert H.; Spencer, James; Walz, Dieter; /SLAC; Plettner, Tomas; Byer, Robert L.; /Stanford U., Phys. Dept.

    2011-11-11T23:59:59.000Z

    In this article we demonstrate the net acceleration of relativistic electrons using a direct, in-vacuum interaction with a laser. In the experiment, an electron beam from a conventional accelerator is first energy modulated at optical frequencies in an inverse-free-electron-laser and bunched in a chicane. This is followed by a second stage optical accelerator to obtain net acceleration. The optical phase between accelerator stages is monitored and controlled in order to scan the accelerating phase and observe net acceleration and deceleration. Phase jitter measurements indicate control of the phase to {approx}13{sup o} allowing for stable net acceleration of electrons with lasers.

  15. Fresnel diffraction patterns as accelerating beams

    E-Print Network [OSTI]

    Zhang, Yiqi; Zheng, Huaibin; Wu, Zhenkun; Li, Yuanyuan; Lu, Keqing; Zhang, Yanpeng

    2013-01-01T23:59:59.000Z

    We demonstrate that beams originating from Fresnel diffraction patterns are self-accelerating in free space. In addition to accelerating and self-healing, they also exhibit parabolic deceleration property, which is in stark contrast to other accelerating beams. We find that the trajectory of Fresnel paraxial accelerating beams is similar to that of nonparaxial Weber beams. Decelerating and accelerating regions are separated by a critical propagation distance, at which no acceleration is present. During deceleration, the Fresnel diffraction beams undergo self-smoothing, in which oscillations of the diffracted waves gradually focus and smooth out at the critical distance.

  16. Computer subroutine for estimating aerodynamic blade loads on Darrieus vertical axis wind turbines. [FORCE code

    SciTech Connect (OSTI)

    Sullivan, W. N.; Leonard, T. M.

    1980-11-01T23:59:59.000Z

    An important aspect of structural design of the Darrieus rotor is the determination of aerodynamic blade loads. This report describes a load generator which has been used at Sandia for quasi-static and dynamic rotor analyses. The generator is based on the single streamtube aerodynamic flow model and is constructed as a FORTRAN IV subroutine to facilitate its use in finite element structural models. Input and output characteristics of the subroutine are described and a complete listing is attached as an appendix.

  17. Spinning Reserve From Responsive Loads

    SciTech Connect (OSTI)

    Kirby, B.J.

    2003-04-08T23:59:59.000Z

    Responsive load is the most underutilized reliability resource available to the power system today. It is currently not used at all to provide spinning reserve. Historically there were good reasons for this, but recent technological advances in communications and controls have provided new capabilities and eliminated many of the old obstacles. North American Electric Reliability Council (NERC), Federal Energy Regulatory Commission (FERC), Northeast Power Coordinating Council (NPCC), New York State Reliability Council (NYSRC), and New York Independent System Operator (NYISO) rules are beginning to recognize these changes and are starting to encourage responsive load provision of reliability services. The Carrier ComfortChoice responsive thermostats provide an example of these technological advances. This is a technology aimed at reducing summer peak demand through central control of residential and small commercial air-conditioning loads. It is being utilized by Long Island Power Authority (LIPA), Consolidated Edison (ConEd), Southern California Edison (SCE), and San Diego Gas and Electric (SDG&E). The technology is capable of delivering even greater response in the faster spinning reserve time frame (while still providing peak reduction). Analysis of demand reduction testing results from LIPA during the summer of 2002 provides evidence to back up this claim. It also demonstrates that loads are different from generators and that the conventional wisdom, which advocates for starting with large loads as better ancillary service providers, is flawed. The tempting approach of incrementally adapting ancillary service requirements, which were established when generators were the only available resources, will not work. While it is easier for most generators to provide replacement power and non-spinning reserve (the slower response services) than it is to supply spinning reserve (the fastest service), the opposite is true for many loads. Also, there is more financial reward for supplying spinning reserve than for supplying the other reserve services as a result of the higher spinning reserve prices. The LIPAedge program (LIPA's demand reduction program using Carrier ComfortChoice thermostats) provides an opportunity to test the use of responsive load for spinning reserve. With potentially 75 MW of spinning reserve capability already installed, this test program can also make an important contribution to the capacity needs of Long Island during the summer of 2003. Testing could also be done at ConEd ({approx}30 MW), SCE ({approx}15 MW), and/or SDG&E ({approx}15 MW). This paper is divided into six chapters. Chapter 2 discusses the contingency reserve ancillary services, their functions in supporting power system reliability, and their technical requirements. It also discusses the policy and tariff requirements and attempts to distinguish between ones that are genuinely necessary and ones that are artifacts of the technologies that were historically used to provide the services. Chapter 3 discusses how responsive load could provide contingency reserves (especially spinning reserve) for the power system. Chapter 4 specifically discusses the Carrier ComfortChoice responsive thermostat technology, the LIPAedge experience with that technology, and how the technology could be used to supply spinning reserve. Chapter 5 discusses a number of unresolved issues and suggests areas for further research. Chapter 6 offers conclusions and recommendations.

  18. Physics Needs for Future Accelerators

    E-Print Network [OSTI]

    Lykken, J D

    2000-01-01T23:59:59.000Z

    Contents: 1. Prologomena to any meta future physics 1.1 Physics needs for building future accelerators 1.2 Physics needs for funding future accelerators 2. Physics questions for future accelerators 2.1 Crimes and misapprehensions 2.1.1 Organized religion 2.1.2 Feudalism 2.1.3 Trotsky was right 2.2 The Standard Model as an effective field theory 2.3 What is the scale of new physics? 2.4 What could be out there? 2.5 Model-independent conclusions 3. Future accelerators 3.1 What is the physics driving the LHC? 3.2 What is the physics driving the LC? 3.2.1 Higgs physics is golden 3.2.2 LHC won't be sufficient to unravel the new physics as the TeV scale 3.2.3 LC precision measurements can pin down new physics scales 3.3 Why a Neutrino Factory? 3.4 Pushing the energy frontier

  19. THE RADIOLOGICAL RESEARCH ACCELERATOR FACILITY

    E-Print Network [OSTI]

    175 THE RADIOLOGICAL RESEARCH ACCELERATOR FACILITY #12;176 #12;177 THE RADIOLOGICAL RESEARCH the microbeam and the track-segment facilities have been utilized in various investigations. Table 1 lists-segment facility. Samples are treated with graded doses of radical scavengers to observe changes in the cluster

  20. Accelerating Multimedia with Enhanced Microprocessors

    E-Print Network [OSTI]

    Lee, Ruby B.

    Accelerating Multimedia with Enhanced Microprocessors A minimalistic set of multimedia instructions introduced into PA-RISC microprocessors implements SIMD-MIMD parallelism with insignificant changes to the underlying microprocessor. Thus, a software video decoder attains MPEG video and audio decom- pression

  1. Accelerators for Intensity Frontier Research

    SciTech Connect (OSTI)

    Derwent, Paul; /Fermilab

    2012-05-11T23:59:59.000Z

    In 2008, the Particle Physics Project Prioritization Panel identified three frontiers for research in high energy physics, the Energy Frontier, the Intensity Frontier, and the Cosmic Frontier. In this paper, I will describe how Fermilab is configuring and upgrading the accelerator complex, prior to the development of Project X, in support of the Intensity Frontier.

  2. Physics Needs for Future Accelerators

    E-Print Network [OSTI]

    Joseph D. Lykken

    2000-01-30T23:59:59.000Z

    Contents: 1. Prologomena to any meta future physics 1.1 Physics needs for building future accelerators 1.2 Physics needs for funding future accelerators 2. Physics questions for future accelerators 2.1 Crimes and misapprehensions 2.1.1 Organized religion 2.1.2 Feudalism 2.1.3 Trotsky was right 2.2 The Standard Model as an effective field theory 2.3 What is the scale of new physics? 2.4 What could be out there? 2.5 Model-independent conclusions 3. Future accelerators 3.1 What is the physics driving the LHC? 3.2 What is the physics driving the LC? 3.2.1 Higgs physics is golden 3.2.2 LHC won't be sufficient to unravel the new physics as the TeV scale 3.2.3 LC precision measurements can pin down new physics scales 3.3 Why a Neutrino Factory? 3.4 Pushing the energy frontier

  3. Thomas Jefferson National Accelerator Facility

    SciTech Connect (OSTI)

    Joseph Grames, Douglas Higinbotham, Hugh Montgomery

    2010-09-01T23:59:59.000Z

    The Thomas Jefferson National Accelerator Facility (Jefferson Lab) in Newport News, Virginia, USA, is one of ten national laboratories under the aegis of the Office of Science of the U.S. Department of Energy (DOE). It is managed and operated by Jefferson Science Associates, LLC. The primary facility at Jefferson Lab is the Continuous Electron Beam Accelerator Facility (CEBAF) as shown in an aerial photograph in Figure 1. Jefferson Lab was created in 1984 as CEBAF and started operations for physics in 1995. The accelerator uses superconducting radio-frequency (srf) techniques to generate high-quality beams of electrons with high-intensity, well-controlled polarization. The technology has enabled ancillary facilities to be created. The CEBAF facility is used by an international user community of more than 1200 physicists for a program of exploration and study of nuclear, hadronic matter, the strong interaction and quantum chromodynamics. Additionally, the exceptional quality of the beams facilitates studies of the fundamental symmetries of nature, which complement those of atomic physics on the one hand and of high-energy particle physics on the other. The facility is in the midst of a project to double the energy of the facility and to enhance and expand its experimental facilities. Studies are also pursued with a Free-Electron Laser produced by an energy-recovering linear accelerator.

  4. High Performance Outdoor Lighting Accelerator

    Broader source: Energy.gov [DOE]

    Hosted by the U.S. Department of Energy (DOE)’s Weatherization and Intergovernmental Programs Office (WIPO), this webinar covered the expansion of the Better Buildings platform to include the newest initiative for the public sector: the High Performance Outdoor Lighting Accelerator (HPOLA).

  5. A Software System for Modeling and Controlling Accelerator Physics Parameters at the Advanced Light Source

    E-Print Network [OSTI]

    Schachinger, L.C.

    2011-01-01T23:59:59.000Z

    and Controlling Accelerator Physics Parameters at theLight Source for accelerator physics studies and accelerator

  6. System and method employing a minimum distance and a load feature database to identify electric load types of different electric loads

    DOE Patents [OSTI]

    Lu, Bin; Yang, Yi; Sharma, Santosh K; Zambare, Prachi; Madane, Mayura A

    2014-12-23T23:59:59.000Z

    A method identifies electric load types of a plurality of different electric loads. The method includes providing a load feature database of a plurality of different electric load types, each of the different electric load types including a first load feature vector having at least four different load features; sensing a voltage signal and a current signal for each of the different electric loads; determining a second load feature vector comprising at least four different load features from the sensed voltage signal and the sensed current signal for a corresponding one of the different electric loads; and identifying by a processor one of the different electric load types by determining a minimum distance of the second load feature vector to the first load feature vector of the different electric load types of the load feature database.

  7. 1994 Pacific Northwest Loads and Resources Study.

    SciTech Connect (OSTI)

    United States. Bonneville Power Administration.

    1994-12-01T23:59:59.000Z

    The 1994 Pacific Northwest Loads and Resources Study presented herein establishes a picture of how the agency is positioned today in its loads and resources balance. It is a snapshot of expected resource operation, contractual obligations, and rights. This study does not attempt to present or analyze future conservation or generation resource scenarios. What it does provide are base case assumptions from which scenarios encompassing a wide range of uncertainties about BPA`s future may be evaluated. The Loads and Resources Study is presented in two documents: (1) this summary of Federal system and Pacific Northwest region loads and resources and (2) a technical appendix detailing the loads and resources for each major Pacific Northwest generating utility. This analysis updates the 1993 Pacific Northwest Loads and Resources Study, published in December 1993. In this loads and resources study, resource availability is compared with a range of forecasted electricity consumption. The Federal system and regional analyses for medium load forecast are presented.

  8. Application of Plasma Waveguides to High Energy Accelerators

    SciTech Connect (OSTI)

    Milchberg, Howard M

    2013-03-30T23:59:59.000Z

    The eventual success of laser-plasma based acceleration schemes for high-energy particle physics will require the focusing and stable guiding of short intense laser pulses in reproducible plasma channels. For this goal to be realized, many scientific issues need to be addressed. These issues include an understanding of the basic physics of, and an exploration of various schemes for, plasma channel formation. In addition, the coupling of intense laser pulses to these channels and the stable propagation of pulses in the channels require study. Finally, new theoretical and computational tools need to be developed to aid in the design and analysis of experiments and future accelerators. Here we propose a 3-year renewal of our combined theoretical and experimental program on the applications of plasma waveguides to high-energy accelerators. During the past grant period we have made a number of significant advances in the science of laser-plasma based acceleration. We pioneered the development of clustered gases as a new highly efficient medium for plasma channel formation. Our contributions here include theoretical and experimental studies of the physics of cluster ionization, heating, explosion, and channel formation. We have demonstrated for the first time the generation of and guiding in a corrugated plasma waveguide. The fine structure demonstrated in these guides is only possible with cluster jet heating by lasers. The corrugated guide is a slow wave structure operable at arbitrarily high laser intensities, allowing direct laser acceleration, a process we have explored in detail with simulations. The development of these guides opens the possibility of direct laser acceleration, a true miniature analogue of the SLAC RF-based accelerator. Our theoretical studies during this period have also contributed to the further development of the simulation codes, Wake and QuickPIC, which can be used for both laser driven and beam driven plasma based acceleration schemes. We will continue our development of advanced simulation tools by modifying the QuickPIC algorithm to allow for the simulation of plasma particle pick-up by the wake fields. We have also performed extensive simulations of plasma slow wave structures for efficient THz generation by guided laser beams or accelerated electron beams. We will pursue experimental studies of direct laser acceleration, and THz generation by two methods, ponderomotive-induced THz polarization, and THz radiation by laser accelerated electron beams. We also plan to study both conventional and corrugated plasma channels using our new 30 TW in our new lab facilities. We will investigate production of very long hydrogen plasma waveguides (5 cm). We will study guiding at increasing power levels through the onset of laser-induced cavitation (bubble regime) to assess the role played by the preformed channel. Experiments in direct acceleration will be performed, using laser plasma wakefields as the electron injector. Finally, we will use 2-colour ionization of gases as a high frequency THz source (<60 THz) in order for femtosecond measurements of low plasma densities in waveguides and beams.

  9. A Novel Approach to Determining Motor Load

    E-Print Network [OSTI]

    Brown, M.

    A NOVEL APPROACH TO DETERMINING MOTOR LOAD by Michael Brown Georgia Tech Research Institute Atlanta, Georgia ABSTRACf Properly sized electric motors are essential if industrial plant efficiency is to be optimized and energy costs... minimized. Because of the difficully in making power measurements on three phase motors, loading is rarely, if ever, checked. A simple indication of motor load can be achieved by measuring operating speed because speed and load are almost linearly...

  10. Communication Load Reduction for Neural Network Implementations

    E-Print Network [OSTI]

    Behnke, Sven

    the total amount of communication load, followed by a placement of partitions onto proces- sors 3]. We

  11. Load Management DSM: Past, Present & Future

    E-Print Network [OSTI]

    Gardner, E.

    1994-01-01T23:59:59.000Z

    . Several current load control programs have discovered that the best FIGURE 6 I marketing method is a "direct mailing" that gets across the message "Load Management will help keep everyone's electrical rates ~ low." The offer of the rebate may catch... thermostat was satisfied or whether the LCR prevented the electrical demand. At the 1993 DA/DSM conference, Scientific-Atlanta introduced the industry's first Load Management Interface &MI) circuit board which fits in a standard load control receiver...

  12. Plug Load Behavioral Change Demonstration Project

    SciTech Connect (OSTI)

    Metzger, I.; Kandt, A.; VanGeet, O.

    2011-08-01T23:59:59.000Z

    This report documents the methods and results of a plug load study of the Environmental Protection Agency's Region 8 Headquarters in Denver, Colorado, conducted by the National Renewable Energy Laboratory. The study quantified the effect of mechanical and behavioral change approaches on plug load energy reduction and identified effective ways to reduce plug load energy. Load reduction approaches included automated energy management systems and behavioral change strategies.

  13. Voltage holding study of 1 MeV accelerator for ITER neutral beam injector

    SciTech Connect (OSTI)

    Taniguchi, M.; Kashiwagi, M.; Umeda, N.; Dairaku, M.; Takemoto, J.; Tobari, H.; Tsuchida, K.; Yamanaka, H.; Watanabe, K.; Kojima, A.; Hanada, M.; Sakamoto, K.; Inoue, T. [Japan Atomic Energy Agency (JAEA), 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan)

    2012-02-15T23:59:59.000Z

    Voltage holding test on MeV accelerator indicated that sustainable voltage was a half of that of ideal quasi-Rogowski electrode. It was suggested that the emission of the clumps is enhanced by a local electric field concentration, which leads to discharge initiation at lower voltage. To reduce the electric field concentration in the MeV accelerator, gaps between the grid supports were expanded and curvature radii at the support corners were increased. After the modifications, the accelerator succeeded in sustaining -1 MV in vacuum without beam acceleration. However, the beam energy was still limited at a level of 900 keV with a beam current density of 150 A/m{sup 2} (346 mA) where the 3 x 5 apertures were used. Measurement of the beam profile revealed that deflection of the H{sup -} ions was large and a part of the H{sup -} ions was intercepted at the acceleration grid. This causes high heat load on the grids and the breakdowns during beam acceleration. To suppress the direct interception, new grid system was designed with proper aperture displacement based on a 3D beam trajectory analysis. As the result, the beam deflection was compensated and the voltage holding during the beam acceleration was improved. Beam parameter of the MeV accelerator was increased to 980 keV, 185 A/m{sup 2} (427 mA), which is close to the requirement of ITER accelerator (1 MeV, 200 A/m{sup 2}).

  14. Properly Evaluating load-following products

    SciTech Connect (OSTI)

    Cavicchi, Joseph; Lemon, Andrew

    2009-01-15T23:59:59.000Z

    The authors briefly survey the jurisdictions where load-following products have been successfully used, examine the characteristics of the load-following products, and explain the shortcomings and inaccurate conclusions of previous analyses. A more thorough analysis reveals that the load-following products fulfill the public policy objectives for which they have been designed and do not adversely impact wholesale electricity markets.

  15. Detecting Load Imbalance on the Cray XT

    E-Print Network [OSTI]

    @cray.com) © Cray Inc. Slide 10 Profile with Load Distribution by Groups Table 1: Profile by Function GroupDetecting Load Imbalance on the Cray XT Luiz DeRose Programming Environment Director Cray Inc. ldr@cray.com #12;Slide 2 Motivation for Load Imbalance Analysis Increasing system software and architecture

  16. Plutonium Immobilization Can Loading Preliminary Specifications

    SciTech Connect (OSTI)

    Kriikku, E.

    1998-11-25T23:59:59.000Z

    This report discusses the Plutonium Immobilization can loading preliminary equipment specifications and includes a process block diagram, process description, equipment list, preliminary equipment specifications, plan and elevation sketches, and some commercial catalogs. This report identifies loading pucks into cans and backfilling cans with helium as the top priority can loading development areas.

  17. Beam heat load in superconducting wigglers

    E-Print Network [OSTI]

    Casalbuoni, S

    2013-01-01T23:59:59.000Z

    The beam heat load is a fundamental input parameter for the design of superconducting wigglers since it is needed to specify the cooling power. In this presentation I will review the possible beam heat load sources and the measurements of beam heat load performed and planned onto the cold vacuum chambers installed at different synchrotron light sources.

  18. accelerator driven radioactive: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    T. Sasa; K. Tsujimoto; H. Takano 3 Developments in laser-driven plasma accelerators CERN Preprints Summary: Laser-driven plasma accelerators provide acceleration gradients...

  19. LASER-PLASMA-ACCELERATOR-BASED GAMMA GAMMA COLLIDERS

    E-Print Network [OSTI]

    Schroeder, C. B.

    2010-01-01T23:59:59.000Z

    LASER-PLASMA-ACCELERATOR-BASED ?? COLLIDERS ? C. B.linear col- lider based on laser-plasma-accelerators arediscussed, and a laser-plasma-accelerator-based gamma-

  20. Cell Component Accelerated Stress Test Protocols for PEM Fuel...

    Broader source: Energy.gov (indexed) [DOE]

    Cell Component Accelerated Stress Test Protocols for PEM Fuel Cells Cell Component Accelerated Stress Test Protocols for PEM Fuel Cells Accelerated Stress Test Protocols for PEM...

  1. Advanced Computing Tools and Models for Accelerator Physics

    E-Print Network [OSTI]

    Ryne, Robert D.

    2008-01-01T23:59:59.000Z

    TOOLS AND MODELS FOR ACCELERATOR PHYSICS * Robert D. Ryne,computing tools for accelerator physics. Following anscale computing in accelerator physics. INTRODUCTION To

  2. accelerate positional cloning: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of velocity is acceleration (i DeTurck, Dennis 2 LTB universes as alternatives to dark energy: does positive averaged acceleration imply positive cosmic acceleration?...

  3. CAS - CERN Accelerator School: Advanced Accelerator Physics Course

    E-Print Network [OSTI]

    2014-01-01T23:59:59.000Z

    This report presents the proceedings of the Course on Advanced Accelerator Physics organized by the CERN Accelerator School. The course was held in Trondheim, Norway from 18 to 29 August 2013, in collaboration with the Norwegian University of Science and Technology. Its syllabus was based on previous courses and in particular on the course held in Berlin 2003 whose proceedings were published as CERN Yellow Report CERN- 2006-002. The field has seen significant advances in recent years and some topics were presented in a new way and other topics were added. The lectures were supplemented with tutorials on key topics and 14 hours of hands on courses on Optics Design and Corrections, RF Measurement Techniques and Beam Instrumentation and Diagnostics. These courses are a key element of the Advanced Level Course.

  4. Accelerator on a Chip: How It Works

    SciTech Connect (OSTI)

    None

    2014-06-30T23:59:59.000Z

    In an advance that could dramatically shrink particle accelerators for science and medicine, researchers used a laser to accelerate electrons at a rate 10 times higher than conventional technology in a nanostructured glass chip smaller than a grain of rice.

  5. FPGA ACCELERATION OF MOLECULAR DYNAMICS SIMULATIONS

    E-Print Network [OSTI]

    Herbordt, Martin

    ' & $ % FPGA ACCELERATION OF MOLECULAR DYNAMICS SIMULATIONS YONGFENG GU Dissertation submitted;BOSTON UNIVERSITY COLLEGE OF ENGINEERING Dissertation FPGA ACCELERATION OF MOLECULAR DYNAMICS SIMULATIONS DYNAMICS SIMULATIONS (Order No. ) YONGFENG GU Boston University, College of Engineering, 2008 Major

  6. MANUFACTURING ACCELERATING THE INCORPORATION OF MATERIALS

    E-Print Network [OSTI]

    Magee, Joseph W.

    MANUFACTURING ACCELERATING THE INCORPORATION OF MATERIALS ADVANCES INTO MANUFACTURING PROCESSES NATIONAL NEED The proposed topic "Accelerating the Incorporation of Materials Advances into Manufacturing organizations, leading researchers from academic institutions, and others. Materials performance is often

  7. Muon acceleration in cosmic-ray sources

    SciTech Connect (OSTI)

    Klein, Spencer R.; Mikkelsen, Rune E. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Becker Tjus, Julia [Fakultät für Physik and Astronomie, Theoretische Physik I, Ruhr-Universität Bochum, D-44780 Bochum (Germany)

    2013-12-20T23:59:59.000Z

    Many models of ultra-high energy cosmic-ray production involve acceleration in linear accelerators located in gamma-ray bursts, magnetars, or other sources. These transient sources have short lifetimes, which necessitate very high accelerating gradients, up to 10{sup 13} keV cm{sup –1}. At gradients above 1.6 keV cm{sup –1}, muons produced by hadronic interactions undergo significant acceleration before they decay. This muon acceleration hardens the neutrino energy spectrum and greatly increases the high-energy neutrino flux. Using the IceCube high-energy diffuse neutrino flux limits, we set two-dimensional limits on the source opacity and matter density, as a function of accelerating gradient. These limits put strong constraints on different models of particle acceleration, particularly those based on plasma wake-field acceleration, and limit models for sources like gamma-ray bursts and magnetars.

  8. CRAD, Engineering - Idaho Accelerated Retrieval Project Phase...

    Broader source: Energy.gov (indexed) [DOE]

    Engineering - Idaho Accelerated Retrieval Project Phase II CRAD, Engineering - Idaho Accelerated Retrieval Project Phase II February 2006 A section of Appendix C to DOE G 226.1-2...

  9. HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS

    E-Print Network [OSTI]

    Taylor, C.

    2011-01-01T23:59:59.000Z

    D. C. 'Niobium-Titanium Superconducting Material s ', in S.14, 1982 HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS C.SUMAG-68 HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS* C.

  10. Load Schedule Coordination for a Large Linear Accelerator: An Operation Powerplay Concept

    E-Print Network [OSTI]

    Johnson, W. H.

    1984-01-01T23:59:59.000Z

    Jwan: 1110.'20 11111.20 161.00 166.00 ]21.20 ]12.20 -"" HW 16.70 21.10 21.70 11.10 17.70Honthly !tall:. 21.10 Iionthly lUn. >IV 26.70 27.70 26.70 21.50 2&.70 li.\\O tllll'ay ow 66.)0 ~.20 111.)] 94.50 \\11.60 In./A ",,,,,,,'1..: li'J-!'to !1.60 H.1'lu... 87.110 78.90 17),29 U~.90 i'lOnthlyl1azH\\l 14.60 1.... 80 11?? 60 IILIO 14.64 18. !'lOnthly Hln. HW Lt..60 2. ,0 1t..60 6.10 14.t.O 2.iO I./AJ'JI PUk1ng: MONTH HW-Mo 101.40 93.90 90.00 81.10 L91.':'0 L1).OO t1onthlyH.llll. HW 17.90 23.60 1...

  11. Development of an Accelerated Ash-Loading Protocol for Diesel Particulate

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny:Revised Finding of No53197E T A * S HBatteries1000: Development of a WetFilters |

  12. The Development of a Small Engine Based Accelerated Ash Loading Protocol |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOriginEducationVideoStrategic| DepartmentDepartmentThe DoDSmallManagement of theDepartment of

  13. Plasma Wakefield Acceleration: How it Works

    SciTech Connect (OSTI)

    None

    2014-11-05T23:59:59.000Z

    This animation explains how electrons can be efficiently accelerated to high energy using wakes created in a plasma.

  14. 1993 Pacific Northwest Loads and Resources Study.

    SciTech Connect (OSTI)

    United States. Bonneville Power Administration.

    1993-12-01T23:59:59.000Z

    The Loads and Resources Study is presented in three documents: (1) this summary of Federal system and Pacific Northwest region loads and resources; (2) a technical appendix detailing forecasted Pacific Northwest economic trends and loads, and (3) a technical appendix detailing the loads and resources for each major Pacific Northwest generating utility. In this loads and resources study, resource availability is compared with a range of forecasted electricity consumption. The forecasted future electricity demands -- firm loads -- are subtracted from the projected capability of existing and {open_quotes}contracted for{close_quotes} resources to determine whether Bonneville Power Administration (BPA) and the region will be surplus or deficit. If resources are greater than loads in any particular year or month, there is a surplus of energy and/or capacity, which BPA can sell to increase revenues. Conversely, if firm loads exceed available resources, there is a deficit of energy and/or capacity, and additional conservation, contract purchases, or generating resources will be needed to meet load growth. The Pacific Northwest Loads and Resources Study analyzes the Pacific Northwest`s projected loads and available generating resources in two parts: (1) the loads and resources of the Federal system, for which BPA is the marketing agency; and (2) the larger Pacific Northwest regional power system, which includes loads and resource in addition to the Federal system. The loads and resources analysis in this study simulates the operation of the power system under the Pacific Northwest Coordination Agreement (PNCA) produced by the Pacific Northwest Coordinating Group. This study presents the Federal system and regional analyses for five load forecasts: high, medium-high, medium, medium-low, and low. This analysis projects the yearly average energy consumption and resource availability for Operating Years (OY) 1994--95 through 2003--04.

  15. AdaptLoad: e ective balancing in clustered web servers under transient load conditions

    E-Print Network [OSTI]

    Riska, Alma

    manner [4, 17]. In this paper we concentrate on e#11;ective load sharing for a clustered web server makes e#11;ective request scheduling a diÆcult task that traditional load balancing methods failAdaptLoad: e#11;ective balancing in clustered web servers under transient load conditions #3; Alma

  16. Balancing load under large and fast load changes in distributed computing systems A case study

    E-Print Network [OSTI]

    Berthomieu, Bernard

    have been written about load sharing or load balancing (see e.g. [2] for references), but our sharing'' [7] technique. Load transfer can be implemented by moving processes at the time they are created (placement), but this method would not handle load implosions. Instead, we will use preemptive migrations

  17. Dynamic Load Balancing of Virtualized Database Services Using Hints and Load

    E-Print Network [OSTI]

    Kemper, Alfons

    server during runtime. Figure 1 shows the load curve of a typical interactive service. In the morningDynamic Load Balancing of Virtualized Database Services Using Hints and Load Forecasting Daniel-organizing infrastructures to react proactively. For this pur- pose we present two techniques: Short-term load forecasting

  18. Efficient Heterogeneous Execution on Large Multicore and Accelerator Platforms: Case Study Using a Block Tridiagonal Solver

    SciTech Connect (OSTI)

    Park, Alfred J [ORNL] [ORNL; Perumalla, Kalyan S [ORNL] [ORNL

    2013-01-01T23:59:59.000Z

    The algorithmic and implementation principles are explored in gainfully exploiting GPU accelerators in conjunction with multicore processors on high-end systems with large numbers of compute nodes, and evaluated in an implementation of a scalable block tridiagonal solver. The accelerator of each compute node is exploited in combination with multicore processors of that node in performing block-level linear algebra operations in the overall, distributed solver algorithm. Optimizations incorporated include: (1) an efficient memory mapping and synchronization interface to minimize data movement, (2) multi-process sharing of the accelerator within a node to obtain balanced load with multicore processors, and (3) an automatic memory management system to efficiently utilize accelerator memory when sub-matrices spill over the limits of device memory. Results are reported from our novel implementation that uses MAGMA and CUBLAS accelerator software systems simultaneously with ACML for multithreaded execution on processors. Overall, using 940 nVidia Tesla X2090 accelerators and 15,040 cores, the best heterogeneous execution delivers a 10.9-fold reduction in run time relative to an already efficient parallel multicore-only baseline implementation that is highly optimized with intra-node and inter-node concurrency and computation-communication overlap. Detailed quantitative results are presented to explain all critical runtime components contributing to hybrid performance.

  19. Numerical modeling of multi-GeV laser wakefield electron acceleration inside a dielectric capillary tube

    SciTech Connect (OSTI)

    Paradkar, B. S.; Cros, B.; Maynard, G. [Laboratoire de Physique des Gaz et des Plasmas, University Paris Sud 11-CNRS, Orsay (France)] [Laboratoire de Physique des Gaz et des Plasmas, University Paris Sud 11-CNRS, Orsay (France); Mora, P. [Centre de Physique Theorique, CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France)] [Centre de Physique Theorique, CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France)

    2013-08-15T23:59:59.000Z

    Numerical modeling of laser wakefield electron acceleration inside a gas filled dielectric capillary tube is presented. Guiding of a short pulse laser inside a dielectric capillary tube over a long distance (?1 m) and acceleration of an externally injected electron bunch to ultra-relativistic energies (?5-10 GeV) are demonstrated in the quasi-linear regime of laser wakefield acceleration. Two dimensional axisymmetric simulations were performed with the code WAKE-EP (Extended Performances), which allows computationally efficient simulations of such long scale plasma. The code is an upgrade of the quasi-static particle code, WAKE [P. Mora and T. M. Antonsen, Jr., Phys. Plasmas 4, 217 (1997)], to simulate the acceleration of an externally injected electron bunch (including beam loading effect) and propagation of the laser beam inside a dielectric capillary. The influence of the transverse electric field of the plasma wake on the radial loss of the accelerated electrons to the dielectric wall is investigated. The stable acceleration of electrons to multi-GeV energy with a non-resonant laser pulse with a large spot-size is demonstrated.

  20. Physics 321 Accelerating Reference Frames II

    E-Print Network [OSTI]

    Hart, Gus

    Physics 321 Hour 25 Accelerating Reference Frames II Consider an accelerating train car Proof 0 and S is a frame rotating with angular velocity . Examples Handout rotation.nb #12;Physics 321 Hour 26 Accelerating Reference Frames III Velocities in Rotating Frames in S0 basis in S' basis In S' basis in S0 basis

  1. Voltage regulation in linear induction accelerators

    DOE Patents [OSTI]

    Parsons, William M. (Santa Fe, NM)

    1992-01-01T23:59:59.000Z

    Improvement in voltage regulation in a Linear Induction Accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance.

  2. Voltage regulation in linear induction accelerators

    DOE Patents [OSTI]

    Parsons, W.M.

    1992-12-29T23:59:59.000Z

    Improvement in voltage regulation in a linear induction accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core is disclosed. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance. 4 figs.

  3. US LHC Accelerator Research Program For the BNL-FNAL-LBNL LHC Accelerator Collaboration

    E-Print Network [OSTI]

    Large Hadron Collider Program

    instruments that will improve the operation of the LHC and help us perform accelerator physics experiments science. · Perform accelerator physics studies and advanced magnet R&D that will result in the IR designsUS LHC Accelerator Research Program Jim Strait For the BNL-FNAL-LBNL LHC Accelerator Collaboration

  4. Tomography of a laser wakefield accelerator Tomography of a laser wakefield accelerator

    E-Print Network [OSTI]

    history of laser-plasma accelerators is reviewed. The excitation of plasma waves by ultra-short laser Tomography of a laser wakefield accelerator Tomography of a laser wakefield accelerator 692220024 #12; Tomography of a laser wakefield accelerator i #12; Tomography of a laser

  5. Industrial applications of electron accelerators

    E-Print Network [OSTI]

    Cleland, M R

    2006-01-01T23:59:59.000Z

    This paper addresses the industrial applications of electron accelerators for modifying the physical, chemical or biological properties of materials and commercial products by treatment with ionizing radiation. Many beneficial effects can be obtained with these methods, which are known as radiation processing. The earliest practical applications occurred during the 1950s, and the business of radiation processing has been expanding since that time. The most prevalent applications are the modification of many different plastic and rubber products and the sterilization of single-use medical devices. Emerging applications are the pasteurization and preservation of foods and the treatment of toxic industrial wastes. Industrial accelerators can now provide electron energies greater than 10 MeV and average beam powers as high as 700 kW. The availability of high-energy, high-power electron beams is stimulating interest in the use of X-rays (bremsstrahlung) as an alternative to gamma rays from radioactive nuclides.

  6. Accelerated expansion from cosmological holography

    E-Print Network [OSTI]

    van Putten, Maurice H P M

    2015-01-01T23:59:59.000Z

    It is shown that holographic cosmology implies an evolving Hubble radius $c^{-1}\\dot{R}_H = -1 + 3\\Omega_m$ in the presence of a dimensionless matter density $\\Omega_m$ scaled to the closure density $3H^2/8\\pi G$, where $c$ denotes the velocity of light and $H$ and $G$ denote the Hubble parameter and Newton's constant. It reveals a dynamical dark energy and a sixfold increase in gravitational attraction to matter on the scale of the Hubble acceleration. It reproduces the transition redshift $z_t\\simeq 0.4$ to the present epoch of accelerated expansion and is consistent with $(q_0,(dq/dz)_0)$ of the deceleration parameter $q(z)=q_0+(dq/dz)_0z$ observed in Type Ia supernovae.

  7. The Particle Accelerator Simulation Code PyORBIT

    SciTech Connect (OSTI)

    Gorlov, Timofey V [ORNL; Holmes, Jeffrey A [ORNL; Cousineau, Sarah M [ORNL; Shishlo, Andrei P [ORNL

    2015-01-01T23:59:59.000Z

    The particle accelerator simulation code PyORBIT is presented. The structure, implementation, history, parallel and simulation capabilities, and future development of the code are discussed. The PyORBIT code is a new implementation and extension of algorithms of the original ORBIT code that was developed for the Spallation Neutron Source accelerator at the Oak Ridge National Laboratory. The PyORBIT code has a two level structure. The upper level uses the Python programming language to control the flow of intensive calculations performed by the lower level code implemented in the C++ language. The parallel capabilities are based on MPI communications. The PyORBIT is an open source code accessible to the public through the Google Open Source Projects Hosting service.

  8. Compensation Techniques in Accelerator Physics

    SciTech Connect (OSTI)

    Hisham Kamal Sayed

    2011-05-31T23:59:59.000Z

    Accelerator physics is one of the most diverse multidisciplinary fields of physics, wherein the dynamics of particle beams is studied. It takes more than the understanding of basic electromagnetic interactions to be able to predict the beam dynamics, and to be able to develop new techniques to produce, maintain, and deliver high quality beams for different applications. In this work, some basic theory regarding particle beam dynamics in accelerators will be presented. This basic theory, along with applying state of the art techniques in beam dynamics will be used in this dissertation to study and solve accelerator physics problems. Two problems involving compensation are studied in the context of the MEIC (Medium Energy Electron Ion Collider) project at Jefferson Laboratory. Several chromaticity (the energy dependence of the particle tune) compensation methods are evaluated numerically and deployed in a figure eight ring designed for the electrons in the collider. Furthermore, transverse coupling optics have been developed to compensate the coupling introduced by the spin rotators in the MEIC electron ring design.

  9. Analytical tools in accelerator physics

    SciTech Connect (OSTI)

    Litvinenko, V.N.

    2010-09-01T23:59:59.000Z

    This paper is a sub-set of my lectures presented in the Accelerator Physics course (USPAS, Santa Rosa, California, January 14-25, 2008). It is based on my notes I wrote during period from 1976 to 1979 in Novosibirsk. Only few copies (in Russian) were distributed to my colleagues in Novosibirsk Institute of Nuclear Physics. The goal of these notes is a complete description starting from the arbitrary reference orbit, explicit expressions for 4-potential and accelerator Hamiltonian and finishing with parameterization with action and angle variables. To a large degree follow logic developed in Theory of Cyclic Particle Accelerators by A.A.Kolmensky and A.N.Lebedev [Kolomensky], but going beyond the book in a number of directions. One of unusual feature is these notes use of matrix function and Sylvester formula for calculating matrices of arbitrary elements. Teaching the USPAS course motivated me to translate significant part of my notes into the English. I also included some introductory materials following Classical Theory of Fields by L.D. Landau and E.M. Liftsitz [Landau]. A large number of short notes covering various techniques are placed in the Appendices.

  10. Accelerator Technology Division progress report, FY 1992

    SciTech Connect (OSTI)

    Schriber, S.O.; Hardekopf, R.A.; Heighway, E.A.

    1993-07-01T23:59:59.000Z

    This report briefly discusses the following topics: The Ground Test Accelerator Program; Defense Free-Electron Lasers; AXY Programs; A Next Generation High-Power Neutron-Scattering Facility; JAERI OMEGA Project and Intense Neutron Sources for Materials Testing; Advanced Free-Electron Laser Initiative; Superconducting Supercollider; The High-Power Microwave (HPM) Program; Neutral Particle Beam (NPB) Power Systems Highlights; Industrial Partnering; Accelerator Physics and Special Projects; Magnetic Optics and Beam Diagnostics; Accelerator Design and Engineering; Radio-Frequency Technology; Accelerator Theory and Free-Electron Laser Technology; Accelerator Controls and Automation; Very High-Power Microwave Sources and Effects; and GTA Installation, Commissioning, and Operations.

  11. Focus Research Areas 1. Fundamental Accelerator Physics: Theory

    E-Print Network [OSTI]

    Kemner, Ken

    Focus Research Areas 1. Fundamental Accelerator Physics: Theory Importance Accelerator physics aspects. Pursuit of fundamental accelerator physics in this sense has contributed significantly to the advance of the accelerator physics knowledgebase during the last several decades, clarifying

  12. Low reflectance radio frequency load

    DOE Patents [OSTI]

    Ives, R. Lawrence; Mizuhara, Yosuke M

    2014-04-01T23:59:59.000Z

    A load for traveling microwave energy has an absorptive volume defined by cylindrical body enclosed by a first end cap and a second end cap. The first end cap has an aperture for the passage of an input waveguide with a rotating part that is coupled to a reflective mirror. The inner surfaces of the absorptive volume consist of a resistive material or are coated with a coating which absorbs a fraction of incident RF energy, and the remainder of the RF energy reflects. The angle of the reflector and end caps is selected such that reflected RF energy dissipates an increasing percentage of the remaining RF energy at each reflection, and the reflected RF energy which returns to the rotating mirror is directed to the back surface of the rotating reflector, and is not coupled to the input waveguide. Additionally, the reflector may have a surface which generates a more uniform power distribution function axially and laterally, to increase the power handling capability of the RF load. The input waveguide may be corrugated for HE11 mode input energy.

  13. FFAG ACCELERATOR PROTON DRIVER FOR NEUTRINO FACTORY.

    SciTech Connect (OSTI)

    RUGGIERO, A.

    2005-06-21T23:59:59.000Z

    This paper is the summary of a conceptual study of a Proton Driver for Neutrino Factory based on the use of a Fixed-Field Alternating-Gradient (FFAG) Accelerator. The required proton energy range for an optimum neutrino production is 5 to 12 GeV. This can be accomplished with a group of three concentric rings each with 807 m circumference [1]. FFAG Accelerators [2] have the capability to accelerate charged particles over a large momentum range ({+-}30-50%) and the feature of constant bending and focusing fields. Particles can be accelerated very fast at the rate given by the accelerating field of RF cavities placed in proper locations between magnets. The performance of FFAG accelerators is to be placed between that of Super-Conducting Linear Accelerators (SCL), with which they share the fast acceleration rate, and Rapid-Cycling Synchrotrons (RCS), as they allow the beam to re-circulate over fewer revolutions. Brookhaven National Laboratory is involved in the study of feasibility of FFAG Accelerators to accelerate intense beams of protons in the GeV energy range for a variety of applications the most important of which is the Upgrade of the Alternating Gradient Synchrotron (AGS) with a new FFAG injector [3] accelerating from 400 MeV to 1.5 GeV. The ring would be housed in the AGS tunnel and has henceforth a circumference of 807 m.

  14. Muon Acceleration in Cosmic-ray Sources

    E-Print Network [OSTI]

    Spencer R. Klein; Rune Mikkelsen; Julia K. Becker Tjus

    2012-08-09T23:59:59.000Z

    Many models of ultra-high energy cosmic-ray production involve acceleration in linear accelerators located in Gamma-Ray Bursts magnetars, or other sources. These source models require very high accelerating gradients, $10^{13}$ keV/cm, with the minimum gradient set by the length of the source. At gradients above 1.6 keV/cm, muons produced by hadronic interactions undergo significant acceleration before they decay. This acceleration hardens the neutrino energy spectrum and greatly increases the high-energy neutrino flux. We rule out many models of linear acceleration, setting strong constraints on plasma wakefield accelerators and on models for sources like Gamma Ray Bursts and magnetars.

  15. Particle acceleration efficiencies in astrophysical shear flows

    E-Print Network [OSTI]

    F. M. Rieger; P. Duffy

    2005-02-04T23:59:59.000Z

    The acceleration of energetic particles in astrophysical shear flows is analyzed. We show that in the presence of a non-relativistic gradual velocity shear, power law particle momentum distributions $f(p) \\propto p^{-(3+\\alpha)}$ may be generated, assuming a momentum-dependent scattering time $\\tau \\propto p^{\\alpha}$, with $\\alpha > 0$. We consider possible acceleration sites in astrophysical jets and study the conditions for efficient acceleration. It is shown, for example, that in the presence of a gradual shear flow and a gyro-dependent particle mean free path, synchrotron radiation losses no longer stop the acceleration once it has started to work efficiently. This suggests that shear acceleration may naturally account for a second, non-thermal population of energetic particles in addition to a shock-accelerated one. The possible relevance of shear acceleration is briefly discussed with reference to the relativistic jet in the quasar 3C 273.

  16. High Performance Computing in Accelerator Science: Past Successes. Future Challenges

    E-Print Network [OSTI]

    Ryne, R.

    2013-01-01T23:59:59.000Z

    High Performance Computing in Accelerator Science: PastAC02- 05CH11231. High Performance Computing in Accelerator

  17. Development of solid-state induction modulators for high PRF accelerators

    SciTech Connect (OSTI)

    Kirbie, H.; Hawkins, S.; Hickman, B. [Lawrence Livermore National Lab., Livermore, CA (United States)] [and others

    1995-07-05T23:59:59.000Z

    Researchers at the Lawrence Livermore National Laboratory and EG&G Energy Measurements are developing a new solid-state power system for two proposed accelerators. One of the accelerators is a circular arrangement of induction cells called a recirculator. It is designed to accelerate heavy ions for an inertial fusion study that proposes to substitute heavy-ion beams for laser beams as the driver for fusion targets. The other accelerator is a linear induction accelerator for electron beams called the Advanced Radiographic Machine (ARM). Both accelerators require their induction cells to be pulsed at a very high repetition frequency (prf) for a short burst containing 5 to 15 pulses. The recirculator has a pulse schedule that varies in pulse width from 1 {mu}s to 400 ns and in prf from 50 to 150 kHz. The ARM accelerator has a pulse schedule that varies in pulse width from 1 {mu}s to 200 ns and in prf from 150 kHz to 1 MHz. The need for complex pulse agility in these accelerators led the authors to examine solid-state switching components that have an on/off capability. The intrinsic speed of solid-state switching satisfies the high prf requirements, while the on/off switching action of some semiconductor devices enables the authors to select an arbitrary pulse width. To accommodate these requirements, they selected field effect transistors (FETs) as the preferred switching elements. The same FET switching technology applies to both accelerators due to their similar pulse requirements. However, these two accelerators differ greatly in peak power and prf range. For example, the power system for the ARM accelerator must supply over 3 kA of beam-current loading to a 150-kV induction cell. For the authors research, two full-scale prototypes were built - a 5-kV induction recirculator cell and a single 15-kV induction modulator for the ARM accelerator. The authors discuss the general network features that are common to both machines, followed by performance and modeling data.

  18. Community Petascale Project for Accelerator Science and Simulation: Advancing Computational Science for Future Accelerators and Accelerator Technologies

    SciTech Connect (OSTI)

    Spentzouris, P.; /Fermilab; Cary, J.; /Tech-X, Boulder; McInnes, L.C.; /Argonne; Mori, W.; /UCLA; Ng, C.; /SLAC; Ng, E.; Ryne, R.; /LBL, Berkeley

    2011-11-14T23:59:59.000Z

    The design and performance optimization of particle accelerators are essential for the success of the DOE scientific program in the next decade. Particle accelerators are very complex systems whose accurate description involves a large number of degrees of freedom and requires the inclusion of many physics processes. Building on the success of the SciDAC-1 Accelerator Science and Technology project, the SciDAC-2 Community Petascale Project for Accelerator Science and Simulation (ComPASS) is developing a comprehensive set of interoperable components for beam dynamics, electromagnetics, electron cooling, and laser/plasma acceleration modelling. ComPASS is providing accelerator scientists the tools required to enable the necessary accelerator simulation paradigm shift from high-fidelity single physics process modeling (covered under SciDAC1) to high-fidelity multiphysics modeling. Our computational frameworks have been used to model the behavior of a large number of accelerators and accelerator R&D experiments, assisting both their design and performance optimization. As parallel computational applications, the ComPASS codes have been shown to make effective use of thousands of processors. ComPASS is in the first year of executing its plan to develop the next-generation HPC accelerator modeling tools. ComPASS aims to develop an integrated simulation environment that will utilize existing and new accelerator physics modules with petascale capabilities, by employing modern computing and solver technologies. The ComPASS vision is to deliver to accelerator scientists a virtual accelerator and virtual prototyping modeling environment, with the necessary multiphysics, multiscale capabilities. The plan for this development includes delivering accelerator modeling applications appropriate for each stage of the ComPASS software evolution. Such applications are already being used to address challenging problems in accelerator design and optimization. The ComPASS organization for software development and applications accounts for the natural domain areas (beam dynamics, electromagnetics, and advanced acceleration), and all areas depend on the enabling technologies activities, such as solvers and component technology, to deliver the desired performance and integrated simulation environment. The ComPASS applications focus on computationally challenging problems important for design or performance optimization to all major HEP, NP, and BES accelerator facilities. With the cost and complexity of particle accelerators rising, the use of computation to optimize their designs and find improved operating regimes becomes essential, potentially leading to significant cost savings with modest investment.

  19. Fermilab | Science | Particle Accelerators | LHC and Future Accelerators

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem NotEnergy,ARMFormsGasReleaseSpeechesHall A ThisFermilab's Accelerator Complex

  20. www.cesos.ntnu.no Author Centre for Ships and Ocean Structures Stationkeeping of moored structures

    E-Print Network [OSTI]

    Nørvåg, Kjetil

    structures in drifting ice Li Zhou May 28th, 2013 #12;2 www.cesos.ntnu.no Author ­ Centre for Ships and Ocean Structures Background Numerical model Ice model test Validation Extension: heading control Conclusions of stationkeeping in ice: · Dynamic global ice loads · Response of floating structures · Local ice loads

  1. Loads Providing Ancillary Services: Review of International Experience

    E-Print Network [OSTI]

    Heffner, Grayson

    2008-01-01T23:59:59.000Z

    for generators. A partial list of load attributes andpartial list includes: • Minimum run times • Minimum off times • Minimum load

  2. Load research manual. Volume 2. Fundamentals of implementing load research procedures

    SciTech Connect (OSTI)

    Brandenburg, L.; Clarkson, G.; Grund, Jr., C.; Leo, J.; Asbury, J.; Brandon-Brown, F.; Derderian, H.; Mueller, R.; Swaroop, R.

    1980-11-01T23:59:59.000Z

    This three-volume manual presents technical guidelines for electric utility load research. Special attention is given to issues raised by the load data reporting requirements of the Public Utility Regulatory Policies Act of 1978 and to problems faced by smaller utilities that are initiating load research programs. In Volumes 1 and 2, procedures are suggested for determining data requirements for load research, establishing the size and customer composition of a load survey sample, selecting and using equipment to record customer electricity usage, processing data tapes from the recording equipment, and analyzing the data. Statistical techniques used in customer sampling are discussed in detail. The costs of load research also are estimated, and ongoing load research programs at three utilities are described. The manual includes guides to load research literature and glossaries of load research and statistical terms.

  3. An Application Specific Memory Characterization Technique for Co-processor Accelerators

    SciTech Connect (OSTI)

    Alam, Sadaf R [ORNL; Smith, Melissa C [ORNL; Vetter, Jeffrey S [ORNL

    2007-01-01T23:59:59.000Z

    Commodity accelerator technologies including reconfigurable devices and graphical processing units (GPUs) provide an order of magnitude performance improvement compared to mainstream microprocessor systems. A number of compute-intensive, scientific applications, therefore, can potentially benefit from commodity computing devices available in the form of co-processor accelerators. However, there has been little progress in accelerating production-level scientific applications using these technologies due to several programming and performance challenges. One of the key performance challenges is performance sustainability. While computation is often accelerated substantially by accelerator devices, the achievable performance is significantly lower once the data transfer costs and overheads are incorporated. We present an application-specific memory characterization technique for an FPGA-accelerated system that enabled us to reduce data transfer overhead for a scientific application by a factor of 5. We classify large data structures in the application according to their read and write characteristics and access patterns. This classification in turn enabled us to sustain a speedup of over three for a full-scale scientific application. Our proposed technique extends to applications that exhibit similar memory behavior and to co-processor accelerator systems that support data streaming and pipelining, and allow overlapped execution between the host and the accelerator device.

  4. Particle acceleration in three-dimensional tearing configurations

    E-Print Network [OSTI]

    Christoph Nodes; Guido T. Birk; Harald Lesch; R. Schopper

    2003-01-17T23:59:59.000Z

    In three-dimensional electromagnetic configurations that result from unstable resistive tearing modes particles can efficiently be accelerated to relativistic energies. To prove this resistive magnetohydrodynamic simulations are used as input configurations for successive test particle simulations. The simulations show the capability of three-dimensional non-linearly evolved tearing modes to accelerate particles perpendicular to the plane of the reconnecting magnetic field components. The simulations differ considerably from analytical approaches by involving a realistic three-dimensional electric field with a non-homogenous component parallel to the current direction. The resulting particle spectra exhibit strong pitch-angle anisotropies. Typically, about 5-8 % of an initially Maxwellian distribution is accelerated to the maximum energy levels given by the macroscopic generalized electric potential structure. Results are shown for both, non-relativistic particle acceleration that is of interest, e.g., in the context of auroral arcs and solar flares, and relativistic particle energization that is relevant, e.g., in the context of active galactic nuclei.

  5. Particle trajectories and acceleration during 3D fan reconnection

    E-Print Network [OSTI]

    S. Dalla; P. K. Browning

    2008-11-07T23:59:59.000Z

    Context. The primary energy release in solar flares is almost certainly due to magnetic reconnection, making this a strong candidate as a mechanism for particle acceleration. While particle acceleration in 2D geometries has been widely studied, investigations in 3D are a recent development. Two main classes of reconnection regimes at a 3D magnetic null point have been identified: fan and spine reconnection Aims. Here we investigate particle trajectories and acceleration during reconnection at a 3D null point, using a test particle numerical code, and compare the efficiency of the fan and spine regimes in generating an energetic particle population. Methods. We calculated the time evolution of the energy spectra. We discuss the geometry of particle escape from the two configurations and characterise the trapped and escaped populations. Results. We find that fan reconnection is less efficent than spine reconnection in providing seed particles to the region of strong electric field where acceleration is possible. The establishment of a steady-state spectrum requires approximately double the time in fan reconnection. The steady-state energy spectrum at intermediate energies (protons 1 keV to 0.1 MeV) is comparable in the fan and spine regimes. While in spine reconnection particle escape takes place in two symmetric jets along the spine, in fan reconnection no jets are produced and particles escape in the fan plane, in a ribbon-like structure.

  6. Test particle simulation of direct laser acceleration in a density-modulated plasma waveguide

    SciTech Connect (OSTI)

    Lin, M.-W.; Jovanovic, I. [Department of Mechanical and Nuclear Engineering, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    2012-11-15T23:59:59.000Z

    Direct laser acceleration (DLA) of electrons by the use of the intense axial electric field of an ultrafast radially polarized laser pulse is a promising technique for future compact accelerators. Density-modulated plasma waveguides can be implemented for guiding the propagation of the laser pulse to extend the acceleration distance and for the quasi-phase-matching between the accelerated electrons and the laser pulse. A test particle model is developed to study the optimal axial density modulation structure of plasma waveguides for laser pulses to efficiently accelerate co-propagating electrons. A simple analytical approach is also presented, which can be used to estimate the energy gain in DLA. The analytical model is validated by the test particle simulation. The effect of injection phase and acceleration of electrons injected at various radial positions are studied. The results indicate that a positively chirped density modulation of the waveguide structure is required to accelerate electron with low initial energies, and can be effectively optimized. A wider tolerance on the injection phase and radial distance from the waveguide axis exists for electrons injected with a higher initial energy.

  7. Bulk Modulus Capacitor Load Cells

    SciTech Connect (OSTI)

    Dickey, C.E.

    1990-04-01T23:59:59.000Z

    Measurement of forces present at various locations within the SSC Model Dipole collared coil assembly is of great practical interest to development engineers. Of particular interest are the forces between coils at the parting plane and forces that exist between coils and pole pieces. It is also desired to observe these forces under the various conditions that a magnet will experience such as: during the collaring process, post-collaring, under the influence of cryogens, and during field excitation. A twenty eight thousandths of an inch thick capacitor load cell which utilizes the hydrostatic condition of a stressed plastic dielectric has been designed. These cells are currently being installed on SSC Model Dipoles. The theory, development, and application of these cells will be discussed.

  8. Tar loads on Omani beaches

    SciTech Connect (OSTI)

    Badawy, M.I.; Al-Harthy, F.T. (National Research Center, Cairo (Egypt))

    1991-11-01T23:59:59.000Z

    Owing to Oman's geographic position and long coastal line, the coastal areas of Oman are particularly vulnerable to oil pollution from normal tanker operations, illegal discharges, and accidental spills as well as local sources of oil input. UNEP carried out a survey on the coasts of Oman to determine the major sources of oil pollution and concluded that the major shoreline pollution problems in Oman arose from operational discharges of oil from passing vessels traffic. The oil, because of the high sea and air temperatures in the area, was subjected to relatively high rates of evaporation and photo-oxidation and tended to arrive at the coast as heavy petroleum particulate residues (tar balls). The aim of the present study was to measure the loads of tar balls in Omani coastal areas and to identify the source of oil pollutants on beaches.

  9. Deuterium accelerator experiments for APT.

    SciTech Connect (OSTI)

    Causey, Rion A. (Sandia National Laboratories, Livermore, CA); Hertz, Kristin L. (Sandia National Laboratories, Livermore, CA); Cowgill, Donald F. (Sandia National Laboratories, Livermore, CA)

    2005-08-01T23:59:59.000Z

    Sandia National Laboratories in California initiated an experimental program to determine whether tritium retention in the tube walls and permeation through the tubes into the surrounding coolant water would be a problem for the Accelerator Production of Tritium (APT), and to find ways to mitigate the problem, if it existed. Significant holdup in the tube walls would limit the ability of APT to meet its production goals, and high levels of permeation would require a costly cleanup system for the cooling water. To simulate tritium implantation, a 200 keV accelerator was used to implant deuterium into Al 6061-T and SS3 16L samples at temperatures and particle fluxes appropriate for APT, for times varying between one week and five months. The implanted samples were characterized to determine the deuterium retention and Permeation. During the implantation, the D(d,p)T nuclear reaction was used to monitor the build-up of deuterium in the implant region of the samples. These experiments increased in sophistication, from mono-energetic deuteron implants to multi-energetic deuteron and proton implants, to more accurately reproduce the conditions expected in APT. Micron-thick copper, nickel, and anodized aluminum coatings were applied to the front surface of the samples (inside of the APT walls) in an attempt to lower retention and permeation. The reduction in both retention and permeation produced by the nickel coatings, and the ability to apply them to the inside of the APT tubes, indicate that both nickel-coated Al 6061-T6 and nickel-coated SS3 16L tubes would be effective for use in APT. The results of this work were submitted to the Accelerator Production of Tritium project in document number TPO-E29-Z-TNS-X-00050, APT-MP-01-17.

  10. System and method employing a self-organizing map load feature database to identify electric load types of different electric loads

    SciTech Connect (OSTI)

    Lu, Bin; Harley, Ronald G.; Du, Liang; Yang, Yi; Sharma, Santosh K.; Zambare, Prachi; Madane, Mayura A.

    2014-06-17T23:59:59.000Z

    A method identifies electric load types of a plurality of different electric loads. The method includes providing a self-organizing map load feature database of a plurality of different electric load types and a plurality of neurons, each of the load types corresponding to a number of the neurons; employing a weight vector for each of the neurons; sensing a voltage signal and a current signal for each of the loads; determining a load feature vector including at least four different load features from the sensed voltage signal and the sensed current signal for a corresponding one of the loads; and identifying by a processor one of the load types by relating the load feature vector to the neurons of the database by identifying the weight vector of one of the neurons corresponding to the one of the load types that is a minimal distance to the load feature vector.

  11. Determinants of multiple measures of acceleration

    SciTech Connect (OSTI)

    Santini, D.J.; Anderson, J.

    1993-08-01T23:59:59.000Z

    Statistical analyses of the acceleration capability of gasoline vehicles have focused on zero to 97 km/h acceleration rates and have concluded that peak power per kilogram is an appropriate single surrogate for acceleration capability. In this paper, statistical methods are used with data for 107 vehicles tested and reported by Consumers Union for 1986--1988 model years to estimate the determinants of contemporary gasoline vehicle acceleration capability under various conditions, adding new variables to the statistical tests reported by others. Like previous studies, this analysis determined that power and weight provide the most information about acceleration capability. Using a model formulation unlike other studies, this study found that engine displacement also provides statistically significant improvements in explanation of 0-48, 0-97, and 48-97 km/h acceleration times. The coefficients of the equations imply that the use of smaller displacement engines, holding peak power constant, diminishes start-up and 0-97 km/h acceleration capability. A separate equation is estimated to illustrate the effects of advanced engine technologies on displacement, controlling for power. This equation is used in conjunction with the acceleration equations to illustrate a method of estimating performance-equivalent engine substitutions when engine technologies change. Transmission type was important for start-up acceleration, with automatic-transmission-equipped vehicles being significantly slower than stick-shift-equipped vehicles. Fuel injection was found to significantly improve start-up acceleration. Variables proxying aerodynamic-drag effects tended to be significant determinants of acceleration in the higher-speed equations, but not for start-up acceleration. Estimated aerodynamic drag effects indicated that drag slows down 0-97, 48-97, and 72-105 km/h acceleration of pickup trucks and sport utility vehicles more than passenger cars and vans.

  12. Soft coincidence in late acceleration

    SciTech Connect (OSTI)

    Campo, Sergio del [Instituto de Fisica, Pontificia Universidad Catolica de Valparaiso, Avenida Brasil 2950, Casilla 4059, Valparaiso (Chile); Herrera, Ramon [Departamento de Ciencias Fisicas, Universidad Andres Bello, Avenida Republica 273, Santiago (Chile); Pavon, Diego [Departamento de Fisica, Facultad de Ciencias, Universidad Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain)

    2005-06-15T23:59:59.000Z

    We study the coincidence problem of late cosmic acceleration by assuming that the present ratio between dark matter and dark energy is a slowly varying function of the scale factor. As the dark energy component we consider two different candidates, first a quintessence scalar field, and then a tachyon field. In either case analytical solutions for the scale factor, the field, and the potential are derived. Both models show a good fit to the recent magnitude-redshift supernovae data. However, the likelihood contours disfavor the tachyon field model as it seems to prefer a excessively high value for the matter component.

  13. Fermilab | Directorate | Fermilab Accelerator Schedules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.New Mexico Feb. 13, 2013 NAME:JobTimothy Meyer ChiefAccelerator

  14. Accelerating Solutions | ornl.gov

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041cloth DocumentationProducts (VAP) VAP7-0973 1 Introduction In theACME - Accelerated

  15. Measured Peak Equipment Loads in Laboratories

    SciTech Connect (OSTI)

    Mathew, Paul A.

    2007-09-12T23:59:59.000Z

    This technical bulletin documents measured peak equipment load data from 39 laboratory spaces in nine buildings across five institutions. The purpose of these measurements was to obtain data on the actual peak loads in laboratories, which can be used to rightsize the design of HVAC systems in new laboratories. While any given laboratory may have unique loads and other design considerations, these results may be used as a 'sanity check' for design assumptions.

  16. Accelerated, energy-conserving BornOppenheimer molecular dynamics via Fock matrix extrapolation

    E-Print Network [OSTI]

    Herbert, John

    in order to accelerate convergence of the electronic structure calculations, can suffer from systematic­Oppenheimer molecular dynamics calculations, especially those that exploit information retained from previous time steps, on a potential energy surface obtained by ``on-the-fly'' solution of the quantum-mechanical electronic structure

  17. Building Technologies Office Load Control Strategies

    Broader source: Energy.gov [DOE]

    BTO researches and implements load control strategies, which support the Sustainable and Holistic IntegratioN of Energy storage and Solar PV (SHINES) FOA.

  18. FINAL PROJECT REPORT LOAD MODELING TRANSMISSION RESEARCH

    E-Print Network [OSTI]

    Lesieutre, Bernard

    2013-01-01T23:59:59.000Z

    of individual appliances. For off-grid applications, solarinappropriate load for an off-grid solar system. Increasedsolar systems in general, and off-grid solar systems in

  19. FINAL PROJECT REPORT LOAD MODELING TRANSMISSION RESEARCH

    E-Print Network [OSTI]

    Lesieutre, Bernard

    2013-01-01T23:59:59.000Z

    Air Conditioner Testing in WECC,” IEEE Power  Engineering Air Conditioner Modeling, WECC Load Modeling Task  Force in power system studies: WECC progress update,? Power and 

  20. FINAL PROJECT REPORT LOAD MODELING TRANSMISSION RESEARCH

    E-Print Network [OSTI]

    Lesieutre, Bernard

    2013-01-01T23:59:59.000Z

    Lights HVAC Figure 15 Demand Response and Market AnalysisHVAC Load % of Total Hour of Day Figure 16 Demand Response and Market

  1. LTB universes as alternatives to dark energy: does positive averaged acceleration imply positive cosmic acceleration?

    E-Print Network [OSTI]

    Antonio Enea Romano

    2007-01-27T23:59:59.000Z

    We show that positive averaged acceleration obtained in LTB models through spatial averaging can require integration over a region beyond the event horizon of the central observer. We provide an example of a LTB model with positive averaged acceleration in which the luminosity distance does not contain information about the entire spatially averaged region, making the averaged acceleration unobservable. Since the cosmic acceleration is obtained from fitting the observed luminosity distance to a FRW model we conclude that in general a positive averaged acceleration in LTB models does not imply a positive FRW cosmic acceleration.

  2. LTB universes as alternatives to dark energy: does positive averaged acceleration imply positive cosmic acceleration?

    E-Print Network [OSTI]

    Romano, A E

    2006-01-01T23:59:59.000Z

    We show that positive averaged acceleration obtained in LTB models through spatial averaging can require integration over a region beyond the event horizon of the central observer. We provide an example of a LTB model with positive averaged acceleration in which the luminosity distance does not contain information about the entire spatially averaged region, making the averaged acceleration unobservable. Since the cosmic acceleration is obtained from fitting the observed luminosity distance to a FRW model we conclude that in general a positive averaged acceleration in LTB models does not imply a positive FRW cosmic acceleration.

  3. Commnity Petascale Project for Accelerator Science and Simulation: Advancing Computational Science for Future Accelerators and Accelerator Technologies

    SciTech Connect (OSTI)

    Spentzouris, Panagiotis; /Fermilab; Cary, John; /Tech-X, Boulder; Mcinnes, Lois Curfman; /Argonne; Mori, Warren; /UCLA; Ng, Cho; /SLAC; Ng, Esmond; Ryne, Robert; /LBL, Berkeley

    2008-07-01T23:59:59.000Z

    The design and performance optimization of particle accelerators is essential for the success of the DOE scientific program in the next decade. Particle accelerators are very complex systems whose accurate description involves a large number of degrees of freedom and requires the inclusion of many physics processes. Building on the success of the SciDAC1 Accelerator Science and Technology project, the SciDAC2 Community Petascale Project for Accelerator Science and Simulation (ComPASS) is developing a comprehensive set of interoperable components for beam dynamics, electromagnetics, electron cooling, and laser/plasma acceleration modeling. ComPASS is providing accelerator scientists the tools required to enable the necessary accelerator simulation paradigm shift from high-fidelity single physics process modeling (covered under SciDAC1) to high-fidelity multi-physics modeling. Our computational frameworks have been used to model the behavior of a large number of accelerators and accelerator R&D experiments, assisting both their design and performance optimization. As parallel computational applications, the ComPASS codes have been shown to make effective use of thousands of processors.

  4. Commnity Petascale Project for Accelerator Science And Simulation: Advancing Computational Science for Future Accelerators And Accelerator Technologies

    SciTech Connect (OSTI)

    Spentzouris, Panagiotis; /Fermilab; Cary, John; /Tech-X, Boulder; Mcinnes, Lois Curfman; /Argonne; Mori, Warren; /UCLA; Ng, Cho; /SLAC; Ng, Esmond; Ryne, Robert; /LBL, Berkeley

    2011-10-21T23:59:59.000Z

    The design and performance optimization of particle accelerators are essential for the success of the DOE scientific program in the next decade. Particle accelerators are very complex systems whose accurate description involves a large number of degrees of freedom and requires the inclusion of many physics processes. Building on the success of the SciDAC-1 Accelerator Science and Technology project, the SciDAC-2 Community Petascale Project for Accelerator Science and Simulation (ComPASS) is developing a comprehensive set of interoperable components for beam dynamics, electromagnetics, electron cooling, and laser/plasma acceleration modelling. ComPASS is providing accelerator scientists the tools required to enable the necessary accelerator simulation paradigm shift from high-fidelity single physics process modeling (covered under SciDAC1) to high-fidelity multiphysics modeling. Our computational frameworks have been used to model the behavior of a large number of accelerators and accelerator R&D experiments, assisting both their design and performance optimization. As parallel computational applications, the ComPASS codes have been shown to make effective use of thousands of processors.

  5. ACE3P Computations of Wakefield Coupling in the CLIC Two-Beam Accelerator

    SciTech Connect (OSTI)

    Candel, Arno; Li, Z.; Ng, C.; Rawat, V.; Schussman, G.; Ko, K.; /SLAC; Syratchev, I.; Grudiev, A.; Wuensch, W.; /CERN

    2010-10-27T23:59:59.000Z

    The Compact Linear Collider (CLIC) provides a path to a multi-TeV accelerator to explore the energy frontier of High Energy Physics. Its novel two-beam accelerator concept envisions rf power transfer to the accelerating structures from a separate high-current decelerator beam line consisting of power extraction and transfer structures (PETS). It is critical to numerically verify the fundamental and higher-order mode properties in and between the two beam lines with high accuracy and confidence. To solve these large-scale problems, SLAC's parallel finite element electromagnetic code suite ACE3P is employed. Using curvilinear conformal meshes and higher-order finite element vector basis functions, unprecedented accuracy and computational efficiency are achieved, enabling high-fidelity modeling of complex detuned structures such as the CLIC TD24 accelerating structure. In this paper, time-domain simulations of wakefield coupling effects in the combined system of PETS and the TD24 structures are presented. The results will help to identify potential issues and provide new insights on the design, leading to further improvements on the novel CLIC two-beam accelerator scheme.

  6. A discrete particle approach to simulate the combined effect of blast and sand impact loading of steel plates

    E-Print Network [OSTI]

    Wadley, Haydn

    A discrete particle approach to simulate the combined effect of blast and sand impact loading March 2011 Keywords: Blast loads Experimental tests Sand ejecta Discrete particles Numerical simulations a b s t r a c t The structural response of a stainless steel plate subjected to the combined blast

  7. Particle acceleration in superluminal strong waves

    E-Print Network [OSTI]

    Teraki, Yuto; Nagataki, Shigehiro

    2015-01-01T23:59:59.000Z

    We calculate the electron acceleration in random superluminal strong waves (SLSWs) and radiation from them by using numerical methods in the context of the termination shock of the pulsar wind nebulae. We pursue the electrons by solving the equation of motion in the analytically expressed electromagnetic turbulences. These consist of primary SLSW and isotropically distributed secondary electromagnetic waves. Under the dominance of the secondary waves, all electrons gain nearly equal energy. On the other hand, when the primary wave is dominant, selective acceleration occurs. The phase of the primary wave felt by the electrons moving nearly along the wavevector changes very slowly compared to the oscillation of the wave, which is called "phase locked", and such electrons are continuously accelerated. This acceleration by SLSWs may play a crucial role in the pre-acceleration for the shock acceleration. In general, the radiation from the phase-locked population is different from the synchro-Compton radiation. How...

  8. Particle acceleration in astrophysical shear flows

    E-Print Network [OSTI]

    Frank M. Rieger; Peter Duffy

    2005-01-10T23:59:59.000Z

    We consider the acceleration of particles due to a velocity shear in relativistic astrophysical flows. The basic physical picture and the formation of power law momentum spectra is discussed for a non-relativistic velocity field using a microscopic approach. We identify possible sites for shear acceleration in relativistic astrophysical jets and analyze their associated acceleration timescales. It is shown in particular that for a mean scattering time $\\tau$ scaling with the gyro-radius, the acceleration timescale for gradual shear scales in the same manner as the synchrotron cooling timescale, so that losses may no longer be able to stop the acceleration once it has started to work efficiently. Finally, the possible role of shear acceleration is discussed with reference to the relativistic jet in the quasar 3C~273.

  9. Relativistic Shocks: Particle Acceleration and Magnetization

    E-Print Network [OSTI]

    Sironi, Lorenzo; Lemoine, Martin

    2015-01-01T23:59:59.000Z

    We review the physics of relativistic shocks, which are often invoked as the sources of non-thermal particles in pulsar wind nebulae (PWNe), gamma-ray bursts (GRBs), and active galactic nuclei (AGN) jets, and as possible sources of ultra-high energy cosmic-rays. We focus on particle acceleration and magnetic field generation, and describe the recent progress in the field driven by theory advances and by the rapid development of particle-in-cell (PIC) simulations. In weakly magnetized or quasi parallel-shocks (where the magnetic field is nearly aligned with the flow), particle acceleration is efficient. The accelerated particles stream ahead of the shock, where they generate strong magnetic waves which in turn scatter the particles back and forth across the shock, mediating their acceleration. In contrast, in strongly magnetized quasi-perpendicular shocks, the efficiencies of both particle acceleration and magnetic field generation are suppressed. Particle acceleration, when efficient, modifies the turbulence ...

  10. Improvement of classical accelerators by lasers

    E-Print Network [OSTI]

    Hora, Heinrich

    1991-01-01T23:59:59.000Z

    Of the unconventional accelerator techniques those including lasers are reported. After explaining the advances by lasers for classical accelerator techniques, as FELs and other methods for 100 GHz generation of GW pulses, a survey is given of far field and near field laser acceleration. Problems of the beat-wave accelerator are discussed and schemes for particle interaction in vacuum without plasma are elaborated. One scheme is the Boreham experiment and another is the acceleration of "standing" wave fields where charged particles are trapped in the intensity minima. Another scheme uses the relativistic acceleration by half waves where the now available petawatt-picosecond laser pulses should produce GeV electron pulses of high luminosity. Increase of these electron enrgies would need very large lasers in the future.

  11. High-level waste at Hanford: Potential for waste loading maximization

    SciTech Connect (OSTI)

    Hrma, P.; Bailey, A.W. [Pacific Northwest Lab., Richland, WA (United States)

    1995-12-31T23:59:59.000Z

    The loading of Hanford nuclear waste in borosilicate glass is limited by phase-related phenomena, such as crystallization or formation of immiscible liquids, and by the breakdown of the glass structure due to an excessive concentration of modifiers. The phase-related phenomena cause both processing and product quality problems. The deterioration of the product durability determines the ultimate waste loading limit if all processing problems are resolved. Concrete examples and mass-balance based calculations show that a substantial potential exists for increasing waste loading of high-level wastes that contain a large fraction of refractory components.

  12. Wind loads on heliostats and parabolic dish collectors: Final subcontractor report

    SciTech Connect (OSTI)

    Peterka, J.A.; Tan, Z.; Bienkiewicz, B.; Cermak, J.E.

    1988-11-01T23:59:59.000Z

    A major intent of this study was to define wind load reduction factors for parabolic dish solar collectors within a field protected by upwind collectors, wind protective fences, or other blockages. This information will help researchers improve the economy of parabolic collector support structures and drive mechanisms. The method used in the study was to generalize wind load data obtained during tests on model collectors placed in a modeled atmospheric wind in a boundary-layer wind tunnel. A second objective of the study was to confirm and document a sensitivity in load to level of turbulence, or gustiness, in the approaching wind. A key finding was that wind-load reduction factors for forces (horizontal and vertical) were roughly similar to those for flat heliostats, with some forces significantly less than those for flat shapes. However, load reductions for moments showed a smaller load reduction, particularly for the azimuth moment. The lack of load reduction could be attributed to collector shape, but specific flow features responsible for and methods to induce a load reduction were not explored. 62 figs., 13 tabs.

  13. Improved Accelerated Stress Tests Based on Fuel Cell Vehicle Data

    SciTech Connect (OSTI)

    Patterson, Timothy [Research Engineer] [Research Engineer; Motupally, Sathya [Research Engineer] [Research Engineer

    2012-06-01T23:59:59.000Z

    UTC will led a top-tier team of industry and national laboratory participants to update and improve DOE’s Accelerated Stress Tests (AST’s) for hydrogen fuel cells. This in-depth investigation will focused on critical fuel cell components (e.g. membrane electrode assemblies - MEA) whose durability represented barriers for widespread commercialization of hydrogen fuel cell technology. UTC had access to MEA materials that had accrued significant load time under real-world conditions in PureMotion® 120 power plant used in transit buses. These materials are referred to as end-of-life (EOL) components in the rest of this document. Advanced characterization techniques were used to evaluate degradation mode progress using these critical cell components extracted from both bus power plants and corresponding materials tested using the DOE AST’s. These techniques were applied to samples at beginning-of-life (BOL) to serve as a baseline. These comparisons advised the progress of the various failure modes that these critical components were subjected to, such as membrane degradation, catalyst support corrosion, platinum group metal dissolution, and others. Gaps in the existing ASTs predicted the degradation observed in the field in terms of these modes were outlined. Using the gaps, new AST’s were recommended and tested to better reflect the degradation modes seen in field operation. Also, BOL components were degraded in a test vehicle at UTC designed to accelerate the bus field operation.

  14. Development of the SCRF Power Coupler for the APT Accelerator

    SciTech Connect (OSTI)

    Schmierer, E.N.; Lujan, R.E.; Rusnak, B.; Smith, B.; Haynes, W.B.; Gautier, C.; Waynert, J.A.; Krawczyk, F.; Gioia, J.

    1999-03-01T23:59:59.000Z

    The team responsible for the design of the Accelerator Production of Tritium (APT) superconducting (SC) radio frequency (RF) power coupler has developed two 700-MHz, helium gas-cooled power couplers. One has a fixed inner conductor and the other has an adjustable inner conductor (gamma prototype and alpha prototype). The power couplers will be performance tested in the near future. This paper discusses the mechanical design and fabrication techniques employed in the development of each power coupler. This includes material selection, copper coating, assembly sequences, and metal joining procedures, as well as the engineering analyses performed to determine the dynamic response of the inner conductors due to environmental excitations. A bellows is used in both prototype inner conductors in the area near the ceramic RF window, to compensate for thermal expansion and mechanical tolerance build-up. In addition, a bellows is used near the tip of the inner conductor of the alpha prototype for running the power coupler after it is installed on the accelerator. Extensive analytical work has been performed to determine the static loads transmitted by the bellows due to thermally induced expansion on the inner conductor and on the RF window. This paper also discusses this analysis, as well as the mechanical analysis performed to determine the final geometric shape of the bellows. Finally, a discussion of the electromagnetic analysis used to optimize the performance of the power couplers is included.

  15. Disposition of nuclear waste using subcritical accelerator-driven systems

    SciTech Connect (OSTI)

    Venneri, F.; Li, N.; Williamson, M.; Houts, M.; Lawrence, G.

    1998-12-31T23:59:59.000Z

    Spent fuel from nuclear power plants contains large quantities of Pu, other actinides, and fission products (FP). This creates challenges for permanent disposal because of the long half-lives of some isotopes and the potential for diversion of the fissile material. Two issues of concern for the US repository concept are: (1) long-term radiological risk peaking tens-of-thousands of years in the future; and (2) short-term thermal loading (decay heat) that limits capacity. An accelerator-driven neutron source can destroy actinides through fission, and can convert long-lived fission products to shorter-lived or stable isotopes. Studies over the past decade have established that accelerator transmutation of waste (ATW) can have a major beneficial impact on the nuclear waste problem. Specifically, the ATW concept the authors are evaluating: (1) destroys over 99.9% of the actinides; (2) destroys over 99.9% of the Tc and I; (3) separates Sr-90 and Cs-137; (4) separates uranium from the spent fuel; (5) produces electric power.

  16. Observation of Enhanced Transformer Ratio in Collinear Wakefield Acceleration

    SciTech Connect (OSTI)

    Jing, C.; Kanareykin, A. [Euclid Techlabs, LLC, Solon, OH-44139 (United States); Power, J.; Conde, M.; Yusof, Z.; Gai, W. [High Energy Physics Division, Argonne National Laboratory, Argonne, IL-60439 (United States)

    2006-11-27T23:59:59.000Z

    The transformer ratio R is a parameter that characterizes the efficiency of the energy transferred from the drive beam to the trailing witness beam passing through a wakefield accelerating structure (all metal or dielectric based) or a plasma chamber. Using a ramped bunch train (RBT) rather than a single drive bunch, the enhanced transformer ratio (ETR) technique is able to increase the transformer ratio R above the ordinary limit of 2 for a single bunch in a collinear wakefield accelerator. The RBT is a train of electron bunches separated by half integer multiples wavelength of the wakefield. The charge of the leading bunch is lowest and subsequent bunch charges are increased in such a way as to maximize R. In this article, an experimental study of this scheme is presented in which an RBT of 2 bunches with charge ratio of 1:2.5 and bunch length {sigma}z = 2 mm were used to enhance the transformer ratio. Measurement results and data analysis show good agreement with theoretical predictions. The ETR technique demonstrated here can be used in any collinear wakefield accelerator configuration, either structure- or plasma-based.

  17. Observation of enhanced transformer ratio in collinear Wakefield acceleration.

    SciTech Connect (OSTI)

    Power, J.; Conde, M.; Yusof, Z.; Gai, W.; Jing, C.; Kanareykin, A.; High Energy Physics; Euclid Techlabs, LLC

    2006-01-01T23:59:59.000Z

    The transformer ratio R is a parameter that characterizes the efficiency of the energy transferred from the drive beam to the trailing witness beam passing through a wakefield accelerating structure (all metal or dielectric based) or a plasma chamber. Using a ramped bunch train (RBT) rather than a single drive bunch, the enhanced transformer ratio (ETR) technique is able to increase the transformer ratio R above the ordinary limit of 2 for a single bunch in a collinear wakefield accelerator. The RBT is a train of electron bunches separated by half integer multiples wavelength of the wakefield. The charge of the leading bunch is lowest and subsequent bunch charges are increased in such a way as to maximize R. In this article, an experimental study of this scheme is presented in which an RBT of 2 bunches with charge ratio of 1:2.5 and bunch length {sigma}{sub z} = 2 mm were used to enhance the transformer ratio. Measurement results and data analysis show good agreement with theoretical predictions. The ETR technique demonstrated here can be used in any collinear wakefield accelerator configuration, either structure- or plasma-based.

  18. Modified Newtonian dynamics from acceleration fluctuations

    E-Print Network [OSTI]

    Thomas F. Jordan

    2004-02-16T23:59:59.000Z

    A speculative mathematical model is used to generate the modified Newtonian dynamics called MOND from fluctuations of the number of quanta of quantized acceleration. The one new parameter can be chosen either to make the transition to modification comparable to that obtained from the functions used to fit data with MOND, or to make the modification at larger accelerations comparable in magnitude to the unexplained accelerations of Pioneer 10 and 11.

  19. Solar system constraints on Rindler acceleration

    E-Print Network [OSTI]

    Sante Carloni; Daniel Grumiller; Florian Preis

    2011-05-09T23:59:59.000Z

    We discuss the classical tests of general relativity in the presence of Rindler acceleration. Among these tests the perihelion shifts give the tightest constraints and indicate that the Pioneer anomaly cannot be caused by a universal solar system Rindler acceleration. We address potential caveats for massive test-objects. Our tightest bound on Rindler acceleration that comes with no caveats is derived from radar echo delay and yields |a|<3nm/s^2.

  20. Accelerator Technology Division progress report, FY 1993

    SciTech Connect (OSTI)

    Schriber, S.O.; Hardekopf, R.A.; Heighway, E.A.

    1993-12-31T23:59:59.000Z

    This report discusses the following topics: A Next-Generation Spallation-Neutron Source; Accelerator Performance Demonstration Facility; APEX Free-Electron Laser Project; The Ground Test Accelerator (GTA) Program; Intense Neutron Source for Materials Testing; Linac Physics and Special Projects; Magnetic Optics and Beam Diagnostics; Radio-Frequency Technology; Accelerator Controls and Automation; Very High-Power Microwave Sources and Effects; and GTA Installation, Commissioning, and Operation.