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1

Plasma Focusing & Dielectric Wakefield Acceleration  

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

pf pf Sign In Launch the Developer Dashboard SLAC National Accelerator Laboratory DOE | Stanford | SLAC | SSRL | LCLS | AD | PPA | Photon Science | PULSE | SIMES FACET User Facility : FACET An Office of Science User Facility Search this site... Search Help (new window) Top Link Bar FACET User Facility FACET Home About FACET FACET Experimental Facilities FACET Users Research at FACET SAREC Expand SAREC FACET FAQs FACET User Facility Quick Launch FACET Users Home FACET Division ARD Home About FACET FACET News FACET Users FACET Experimental Facilities FACET Research Expand FACET Research FACET Images Expand FACET Images SAREC Expand SAREC FACET Project Site (restricted) FACET FAQs FACET Site TOC All Site Content Department of Energy Page Content Plasma Focusing & Dielectric Wakefield Acceleration

2

Dielectric Wakefield Accelerator to drive the future FEL Light Source.  

SciTech Connect (OSTI)

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.

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

2011-04-20T23:59:59.000Z

3

Ultra-High Gradient Dielectric Wakefield Accelerator Experiments  

SciTech Connect (OSTI)

Ultra-high gradient dielectric wakefield accelerators are a potential option for a linear collider afterburner since they are immune to the ion collapse and electron/positron asymmetry problems implicit in a plasma based afterburner. The first phase of an experiment to study the performance of dielectric Cerenkov wakefield accelerating structures at extremely high gradients in the GV/m range has been completed. The experiment took advantage of the unique SLAC FFTB electron beam and its ultra-short pulse lengths and high currents (e.g., {sigma}{sub z} = 20 {micro}m at Q = 3 nC). The FFTB electron beam was successfully focused down and sent through short lengths of fused silica capillary tubing (ID = 200 {micro}m/OD = 325 {micro}m). The pulse length of the electron beam was varied to produce a range of electric fields between 2 and 20 GV/m at the inner surface of the dielectric tubes. We observed a sharp increase in optical emissions from the capillaries in the middle part of this surface field range which we believe indicates the transition between sustainable field levels and breakdown. If this initial interpretation is correct, the surfaced fields that were sustained equate to on axis accelerating field of several GV/m. In future experiments being developed for the SLAC SABER and BNL ATF we plan to use the coherent Cerenkov radiation emitted from the capillary tube as a field strength diagnostic and demonstrate GV/m range particle energy gain.

Thompson, M C; Badakov, H; Rosenzweig, J B; Travish, G; Hogan, M; Ischebeck, R; Kirby, N; Siemann, R; Walz, D; Muggli, P; Scott, A; Yoder, R

2006-08-04T23:59:59.000Z

4

Ultra-High Gradient Dielectric Wakefield Accelerator Experiments  

SciTech Connect (OSTI)

Ultra-high gradient dielectric wakefield accelerators are a potential option for a linear collider afterburner since they are immune to the ion collapse and electron/positron asymmetry problems implicit in a plasma based afterburner. The first phase of an experiment to study the performance of dielectric Cerenkov wakefield accelerating structures at extremely high gradients in the GV/m range has been completed. The experiment took advantage of the unique SLAC FFTB electron beam and its ultra-short pulse lengths and high currents (e.g., {sigma}z = 20 {mu}m at Q = 3 nC). The FFTB electron beam was successfully focused down and sent through short lengths of fused silica capillary tubing (ID = 200 {mu}m / OD = 325 {mu}m). The pulse length of the electron beam was varied to produce a range of electric fields between 2 and 20 GV/m at the inner surface of the dielectric tubes. We observed a sharp increase in optical emissions from the capillaries in the middle part of this surface field range which we believe indicates the transition between sustainable field levels and breakdown. If this initial interpretation is correct, the surfaced fields that were sustained equate to on axis accelerating field of several GV/m. In future experiments being developed for the SLAC SABER and BNL ATF we plan to use the coherent Cerenkov radiation emitted from the capillary tube as a field strength diagnostic and demonstrate GV/m range particle energy gain.

Thompson, M. C. [Lawrence Livermore National Laboratory, Livermore, California, 90095 (United States); Badakov, H.; Rosenzweig, J. B.; Travis, G. [UCLA Department of Physics and Astronomy, Los Angeles, California, 90095 (United States); Hogan, M.; Ischebeck, R.; Kirby, N.; Siemann, R.; Walz, D. [Stanford Linear Accelerator Center, Stanford, California, 94309 (United States); Muggli, P. [University of Southern California Los Angeles, California, 90089 (United States); Scott, A. [UCSB Department of Physics, Santa Barbara, California, 93106 (United States); Yoder, R. [Manhattan College, Riverdale, New York, 10471 (United States)

2006-11-27T23:59:59.000Z

5

Laser Wakefield Particle Accelerators Project at NERSC  

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

Laser Wakefield Particle Acceleration Laser Wakefield Particle Acceleration Vorpal.jpg Key Challenges: Design of multiple-staged, 10-GeV laser-wakefield plasma accelerated...

6

Computational studies and optimization of wakefield accelerators  

E-Print Network [OSTI]

optimization of wakefield accelerators C. G. R. Geddes 1 ,from the U.S. -LHC Accelerator Research Program (LARP),driven plasma wakefield accelerators produce accelerating

Geddes, C.G.R.

2010-01-01T23:59:59.000Z

7

Plasma Wakefield Acceleration  

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

rpwa rpwa Sign In Launch the Developer Dashboard SLAC National Accelerator Laboratory DOE | Stanford | SLAC | SSRL | LCLS | AD | PPA | Photon Science | PULSE | SIMES FACET User Facility : FACET An Office of Science User Facility Search this site... Search Help (new window) Top Link Bar FACET User Facility FACET Home About FACET FACET Experimental Facilities FACET Users Research at FACET SAREC Expand SAREC FACET FAQs FACET User Facility Quick Launch FACET Users Home FACET Division ARD Home About FACET FACET News FACET Users FACET Experimental Facilities FACET Research Expand FACET Research FACET Images Expand FACET Images SAREC Expand SAREC FACET Project Site (restricted) FACET FAQs FACET Site TOC All Site Content Department of Energy Page Content Plasma Wakefield Acceleration

8

Modeling Laser Wakefield Accelerators in a Lorentz Boosted Frame  

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

Modeling Laser Wakefield Accelerators in a Lorentz Boosted Frame Modeling Laser Wakefield Accelerators in a Lorentz Boosted Frame VayBoost.gif An image showing the "boosted frame,"...

9

Development of high gradient laser wakefield accelerators towards nuclear detection applications at LBNL  

E-Print Network [OSTI]

laser wakefield accelerators towards nuclear detectionRecent laser wakefield accelerator experiments at LBNLscaling of laser driven accelerators to GeV energies. Stable

Geddes, Cameron GR

2010-01-01T23:59:59.000Z

10

Modeling Laser Wakefield Accelerators in a Lorentz Boosted Frame  

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

Modeling Laser Modeling Laser Wakefield Accelerators in a Lorentz Boosted Frame Modeling Laser Wakefield Accelerators in a Lorentz Boosted Frame VayBoost.gif An image showing the "boosted frame," in which the observer moves at near light speed. The laser pulse is represented in blue and red; the wakefields are colored pale blue and yellow. In this frame, the plasma (yellow box) has contracted and the wavefronts are fewer and farther apart, resulting in far fewer calculations and faster results. Why it Matters: Laser driven plasma waves can produce accelerating gradients orders of magnitude greater than standard accelerating structures. High quality electron beams of energy up to 1 GeV have been produced in just a few centimeters and 10-GeV stages being planned as

11

Cast dielectric composite linear accelerator  

DOE Patents [OSTI]

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.

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

2009-11-10T23:59:59.000Z

12

Outline History Basic Theory Research Future Accelerators References Brief Overview of Wakefield  

E-Print Network [OSTI]

Outline History Basic Theory Research Future Accelerators References Brief Overview of Wakefield Acceleration Eugene S. Evans1 November 9, 2010 1 University of California, Berkeley Eugene S. Evans Brief Overview of Wakefield Acceleration #12;Outline History Basic Theory Research Future Accelerators References

Budker, Dmitry

13

Measurement of the Decelerating Wake in a Plasma Wakefield Accelerator  

SciTech Connect (OSTI)

Recent experiments at SLAC have shown that high gradient acceleration of electrons is achievable in meter scale plasmas. Results from these experiments show that the wakefield is sensitive to parameters in the electron beam which drives it. In the experiment the bunch lengths were varied systematically at constant charge. The effort to extract a measurement of the decelerating wake from the maximum energy loss of the electron beam is discussed.

Blumenfeld, I.; Decker, F. J.; Hogan, M. J.; Ischebeck, R.; Iverson, R. H.; Kirby, N.; Siemann, R. H.; Walz, D. R. [Stanford Linear Accelerator Center, Stanford University, Stanford, California 94305 (United States); Clayton, C. E.; Huang, C.; Joshi, C.; Lu, W.; Marsh, K. A.; Mori, W. B.; Zhou, M. [University of California, Los Angeles, California 90095 (United States); Katsouleas, T.; Muggli, P.; Oz, E. [University of Southern California, Los Angeles, California 90089 (United States)

2009-01-22T23:59:59.000Z

14

Mesurement of the Decelerating Wake in a Plasma Wakefield Accelerator  

SciTech Connect (OSTI)

Recent experiments at SLAC have shown that high gradient acceleration of electrons is achievable in meter scale plasmas. Results from these experiments show that the wakefield is sensitive to parameters in the electron beam which drives it. In the experiment the bunch lengths were varied systematically at constant charge. The effort to extract a measurement of the decelerating wake from the maximum energy loss of the electron beam is discussed.

Blumenfeld, I; Clayton, C.E.; Decker, F.J.; Hogan, M.J.; Huang, C.; Ischebeck, R.; Iverson, R.H.; Joshi, C.; Katsouleas, T.; Kirby, N.; Lu, W.; Marsh, K.A.; Mori, W.B.; Muggli, P; Oz, E.; Siemann, R.H.; Walz, D.R.; Zhou, M.; /SLAC /UCLA /USC

2008-09-24T23:59:59.000Z

15

Emittance Measurements of Trapped Electrons from a Plasma Wakefield Accelerator  

SciTech Connect (OSTI)

Recent electron beam driven plasma wakefield accelerator experiments carried out at SLAC showed trapping of plasma electrons. These trapped electrons appeared on an energy spectrometer with smaller transverse size than the beam driving the wake. A connection is made between transverse size and emittance; due to the spectrometer's resolution, this connection allows for placing an upper limit on the trapped electron emittance. The upper limit for the lowest normalized emittance measured in the experiment is 1 mm {center_dot} mrad.

Kirby, N.; Berry, M.; Blumenfeld, I.; Decker, F.-J.; Hogan, M.J.; Ischebeck, R.; Iverson, R.; Siemann, R.; Walz, D.; /SLAC; Clayton, C.E.; Huang, C.; Joshi, C.; Lu, W.; Marsh, K.A.; Mori, W.B.; Zhou, M.; /UCLA; Katsouleas, T.C.; Muggli, P.; Oz, E.; /Southern California U.

2007-06-28T23:59:59.000Z

16

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

ScienceCinema (OSTI)

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.

Andrei Seryi

2010-01-08T23:59:59.000Z

17

Unphysical kinetic effects in particle-in-cell modeling of laser wakefield accelerators Estelle Cormier-Michel,1,2  

E-Print Network [OSTI]

Unphysical kinetic effects in particle-in-cell modeling of laser wakefield accelerators Estelle of laser wakefield accelerators using particle-in-cell codes are investigated. A dark current free laser wakefield accelerator stage, in which no trapping of background plasma electrons into the plasma wave should

Geddes, Cameron Guy Robinson

18

Computational studies and optimization of wakefield accelerators  

E-Print Network [OSTI]

-frequency accelerators, offering compactness and ultrafast bunches to extend the frontiers of high energy physics behind recent demonstration of narrow energy spread bunches. Benchmarking between codes is establishing sources to design next-generation experiments and to use in applications in high energy physics and light

Geddes, Cameron Guy Robinson

19

Increasing the transformer ratio at the Argonne wakefield accelerator  

Science Journals Connector (OSTI)

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.

C. Jing, J. G. Power, M. Conde, W. Liu, Z. Yusof, A. Kanareykin, and W. Gai

2011-02-16T23:59:59.000Z

20

Beam Head Erosion in Self-Ionized Plasma Wakefield Accelerators  

SciTech Connect (OSTI)

In the recent plasma wakefield accelerator experiments at SLAC, the energy of the particles in the tail of the 42 GeV electron beam were doubled in less than one meter [1]. Simulations suggest that the acceleration length was limited by a new phenomenon--beam head erosion in self-ionized plasmas. In vacuum, a particle beam expands transversely in a distance given by {beta}*. In the blowout regime of a plasma wakefield [2], the majority of the beam is focused by the ion channel, while the beam head slowly spreads since it takes a finite time for the ion channel to form. It is observed that in self-ionized plasmas, the head spreading is exacerbated compared to that in pre-ionized plasmas, causing the ionization front to move backward (erode). A simple theoretical model is used to estimate the upper limit of the erosion rate for a bi-gaussian beam by assuming free expansion of the beam head before the ionization front. Comparison with simulations suggests that half this maximum value can serve as an estimate for the erosion rate. Critical parameters to the erosion rate are discussed.

Berry, M.K.; Blumenfeld, I.; Decker, F.J.; Hogan, M.J.; Ischebeck, R.; Iverson, R.H.; Kirby, N.A.; Siemann, Robert H.; Walz, D.R.; /SLAC; Clayton, C.E.; Huang, C.; Joshi, C.; Lu, W.; Marsh, K.A.; Mori, W.B.; Zhou, M.; /UCLA; Katsouleas, T.C.; Muggli, P.; Oz, E.; /Southern California U.

2008-01-28T23:59:59.000Z

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Efficient operating mode of the plasma wakefield accelerator  

SciTech Connect (OSTI)

A new operating mode of the plasma wakefield accelerator is found at which high efficiency of the driver-to-witness energy exchange can be achieved simultaneously with high transformer ratio and low energy spread. The efficient acceleration is realized in the blowout regime with a high-current moderate-length driver, if most of the driver and the whole witness are inside the cavern, and the beams are shaped to flatten the profile of the longitudinal electric field. The efficient regime can be demonstrated with state-of-the-art electron beams, but requires a longitudinal compression of the drive beam, high density plasma, and precise control of driver and witness shapes.

Lotov, K.V. [Budker Institute of Nuclear Physics, 630090 Novosibirsk (Russian Federation)

2005-05-15T23:59:59.000Z

22

Preliminary Results from the UCLA/SLAC Ultra-High Gradient CerenkovWakefield Accelerator Experiment  

SciTech Connect (OSTI)

The first phase of an experiment to study the performance of dielectric Cerenkov wakefield accelerating structures at extremely high gradients in the GV/m range has been completed. This experiment takes advantage of the unique SLAC FFTB electron beam and its demonstrated ultra-short pulse lengths and high currents (e.g., {sigma}{sub z} = 20 {micro}m at Q = 3 nC). The FFTB electron beam has been successfully focused down and sent through varying lengths of fused silica capillary tubing with two different sizes: ID = 200 {micro}m/OD = 325 {micro}m and ID = 100 {micro}m/OD = 325 {micro}m. The pulse length of the electron beam was varied in the range 20 {micro}m < {sigma}{sub z} < 100 {micro}m which produced a range of electric fields between 2 and 20 GV/m at the inner surface of the dielectric tubes. We observed a sharp increase in optical emissions from the capillaries in the middle part of this surface field range which we believe indicates the transition between sustainable field levels and breakdown. If this initial interpretation is correct, the surfaced fields that were sustained equate to on axis accelerating field of several GV/m. In future experiments we plan to collect and measure coherent Cerenkov radiation emitted from the capillary tube to gain more information about the strength of the accelerating fields.

Thompson, M.C.; Badakov, H.; Rosenzweig, J.B.; Travish, G.; /UCLA; Hogan, M.; Ischebeck, R.; Kirby, N.; Siemann, R.; Walz, D.; /SLAC; Muggli, P.; /Southern California U.; Scott, A.; /UC, Santa Barbara; Yoder, R.; /Manhattan Coll., Riverdale

2008-02-06T23:59:59.000Z

23

UNDULATOR-BASED LASER WAKEFIELD ACCELERATOR ELECTRON BEAM DIAGNOSTIC  

SciTech Connect (OSTI)

to couple the THUNDER undulator to the LOASIS Lawrence Berkeley National Laboratory (LBNL) laser wakefield accelerator (LWFA). Currently the LWFA has achieved quasi-monoenergetic electron beams with energies up to 1 GeV. These ultra-short, high-peak-current, electron beams are ideal for driving a compact XUV free electron laser (FEL). Understanding the electron beam properties such as the energy spread and emittance is critical for achieving high quality light sources with high brightness. By using an insertion device such as an undulator and observing changes in the spontaneous emission spectrum, the electron beam energy spread and emittance can be measured with high precision. The initial experiments will use spontaneous emission from 1.5 m of undulator. Later experiments will use up to 5 m of undulator with a goal of a high gain, XUV FEL.

Bakeman, M.S.; Fawley, W.M.; Leemans, W. P.; Nakamura, K.; Robinson, K.E.; Schroeder, C.B.; Toth, C.

2009-05-04T23:59:59.000Z

24

Effect of plasma inhomogeneity on plasma wakefield acceleration driven by long bunches  

SciTech Connect (OSTI)

Effects of plasma inhomogeneity on self-modulating proton bunches and accelerated electrons were studied numerically. The main effect is the change of the wakefield wavelength which results in phase shifts and loss of accelerated particles. This effect imposes severe constraints on density uniformity in plasma wakefield accelerators driven by long particle bunches. The transverse two stream instability that transforms the long bunch into a train of micro-bunches is less sensitive to density inhomogeneity than are the accelerated particles. The bunch freely passes through increased density regions and interacts with reduced density regions.

Lotov, K. V. [Budker Institute of Nuclear Physics SB RAS, 630090 Novosibirsk, Russia and Novosibirsk State University, 630090 Novosibirsk (Russian Federation); Pukhov, A. [Institut fuer Theoretische Physik I, Heinrich-Heine-Universitaet Duesseldorf, 40225 Duesseldorf (Germany); Caldwell, A. [Max-Planck-Institut fuer Physik, 80805 Muenchen (Germany)

2013-01-15T23:59:59.000Z

25

Electromagnetic forces on the dielectric layers of the planar optical Bragg acceleration structure  

SciTech Connect (OSTI)

Optical Bragg acceleration structures are waveguides with a vacuum core and dielectric layers as a cladding, designed to guide laser light at the speed-of-light TM mode and accelerate charged particles. In this study, we analyze the electromagnetic forces exerted on the dielectric layers of a planar structure by both the guided laser light and the wake-field of moving charges. The distribution of the volume force densities, as well as the surface force densities, in the interfaces between the layers as a result of the laser propagation is given, and analytic scaling laws for the maximal values are obtained. Separation of the wake-field into the structure's eigenmodes is essential in order to determine the different contributions of the wake-field to the total impulse that acts on the structure. It is shown that the impact of the wake-field on the structure results almost entirely from the fundamental TM mode. While the total force on the dielectric layers may be significantly stronger than the gravitational force, we show that for typical structures, the pressures that develop are orders of magnitude below the damage threshold.

Mizrahi, Amit; Schaechter, Levi [Department of Electrical Engineering, Technion--Israel Institute of Technology, Haifa 32000 (Israel)

2006-09-15T23:59:59.000Z

26

Properties of Trapped Electron Bunches in a Plasma Wakefield Accelerator  

SciTech Connect (OSTI)

Plasma-based accelerators use the propagation of a drive bunch through plasma to create large electric fields. Recent plasma wakefield accelerator (PWFA) experiments, carried out at the Stanford Linear Accelerator Center (SLAC), successfully doubled the energy for some of the 42 GeV drive bunch electrons in less than a meter; this feat would have required 3 km in the SLAC linac. This dissertation covers one phenomenon associated with the PWFA, electron trapping. Recently it was shown that PWFAs, operated in the nonlinear bubble regime, can trap electrons that are released by ionization inside the plasma wake and accelerate them to high energies. These trapped electrons occupy and can degrade the accelerating portion of the plasma wake, so it is important to understand their origins and how to remove them. Here, the onset of electron trapping is connected to the drive bunch properties. Additionally, the trapped electron bunches are observed with normalized transverse emittance divided by peak current, {epsilon}{sub N,x}/I{sub t}, below the level of 0.2 {micro}m/kA. A theoretical model of the trapped electron emittance, developed here, indicates that the emittance scales inversely with the square root of the plasma density in the non-linear 'bubble' regime of the PWFA. This model and simulations indicate that the observed values of {epsilon}{sub N,x}/I{sub t} result from multi-GeV trapped electron bunches with emittances of a few {micro}m and multi-kA peak currents. These properties make the trapped electrons a possible particle source for next generation light sources. This dissertation is organized as follows. The first chapter is an overview of the PWFA, which includes a review of the accelerating and focusing fields and a survey of the remaining issues for a plasma-based particle collider. Then, the second chapter examines the physics of electron trapping in the PWFA. The third chapter uses theory and simulations to analyze the properties of the trapped electron bunches. Chapters four and five present the experimental diagnostics and measurements for the trapped electrons. Next, the sixth chapter introduces suggestions for future trapped electron experiments. Then, Chapter seven contains the conclusions. In addition, there is an appendix chapter that covers a topic which is extraneous to electron trapping, but relevant to the PWFA. This chapter explores the feasibility of one idea for the production of a hollow channel plasma, which if produced could solve some of the remaining issues for a plasma-based collider.

Kirby, Neil; /SLAC

2009-10-30T23:59:59.000Z

27

Two GeV Electrons Achieved by Laser Plasma Wakefield Acceleration | U.S.  

Office of Science (SC) Website

Two GeV Electrons Achieved by Laser Plasma Wakefield Acceleration Two GeV Electrons Achieved by Laser Plasma Wakefield Acceleration High Energy Physics (HEP) HEP Home About Research Facilities Science Highlights Benefits of HEP Funding Opportunities Advisory Committees News & Resources Contact Information High Energy Physics U.S. Department of Energy SC-25/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3624 F: (301) 903-2597 E: sc.hep@science.doe.gov More Information » July 2013 Two GeV Electrons Achieved by Laser Plasma Wakefield Acceleration Scientists at University of Texas, Austin, accelerate electrons to 2 GeV in table top apparatus. Print Text Size: A A A Subscribe FeedbackShare Page Click to enlarge photo. Enlarge Photo Image courtesy of Neil Fazel The inside of the University of Texas, Austin, vacuum chamber where

28

Virtual gap dielectric wall accelerator  

DOE Patents [OSTI]

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.

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

2013-11-05T23:59:59.000Z

29

A multi-beam, multi-terawatt Ti:sapphire laser system for laser wake-field acceleration studies  

E-Print Network [OSTI]

­plasma interaction studies, such as development of laser wake-field accelerators [1-4], X-ray lasers, and laserA multi-beam, multi-terawatt Ti:sapphire laser system for laser wake-field acceleration studies 71R0259, 1 Cyclotron Rd., Berkeley, CA 94720, USA, e-mail: ctoth@lbl.gov Abstract. The Lasers

Geddes, Cameron Guy Robinson

30

Laser-driven plasma-based accelerators: Wakefield excitation, channel guiding, and laser triggered particle injection*  

E-Print Network [OSTI]

Laser-driven plasma-based accelerators: Wakefield excitation, channel guiding, and laser triggered; accepted 18 February 1998 Plasma-based accelerators are discussed in which high-power short pulse lasers are the power source, suitably tailored plasma structures provide guiding of the laser beam and support large

Wurtele, Jonathan

31

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

E-Print Network [OSTI]

this breakdown constraint. Two schemes of plasma excitation have been the focus of much of the work: the laserMultimode Analysis of the Hollow Plasma Channel Wakefield Accelerator C. B. Schroeder,1 D. H April 1998) The hollow plasma channel is analyzed as an accelerating structure. The excitation

Geddes, Cameron Guy Robinson

32

Role of stochastic heating in wakefield acceleration when optical injection is used  

SciTech Connect (OSTI)

The dynamics of an electron in two counterpropagating waves is investigated. Conditions for stochastic acceleration are derived. The possibility of stochastic heating is confirmed when two waves interact with low density plasma by performing PIC (Particle In Cell) code simulations. It is shown that stochastic heating can play an important role in laser wakefield acceleration. When considering low density plasma interacting with a high intensity wave perturbed by a low intensity counterpropagating wave, stochastic heating can provide electrons with the right momentum for trapping in the wakefield. The influence of stochastic acceleration on the trapping of electrons is compared to the one of the beatwave force which is responsible for cold injection. To do so, several polarizations for the colliding pulses are considered. For some value of the plasma density and pulse duration, a transition from an injection due to stochastic acceleration to a cold injection dominated regimeregarding the trapped chargehas been observed from 2D and 3D PIC code simulations. This transition is ruled by the ratio of the interaction length of the pulses to the longitudinal size of the bubble. When the interaction length of the laser pulses reaches the radius of the accelerating cavity stochastic heating becomes dominant, and might be necessary to get electrons trapped into the wakefield, when wakefield inhibition grows with plasma density.

Rassou, S.; Bourdier, A.; Drouin, M. [CEA, DAM, DIF, 91297 Arpajon (France)

2014-08-15T23:59:59.000Z

33

Downramp-assisted underdense photocathode electron bunch generation in plasma wakefield accelerators  

E-Print Network [OSTI]

It is shown that the requirements for high quality electron bunch generation and trapping from an underdense photocathode in plasma wakefield accelerators can be substantially relaxed through localizing it on a plasma density downramp. This depresses the phase velocity of the accelerating electric field until the generated electrons are in phase, allowing for trapping in shallow trapping potentials. As a consequence the underdense photocathode technique is applicable by a much larger number of accelerator facilities. Furthermore, dark current generation is effectively suppressed.

Knetsch, Alexander; Wittig, Georg; Groth, Henning; Xi, Yunfeng; Deng, Aihua; Rosenzweig, James Benjamin; Bruhwiler, David Leslie; Smith, Johnathan; Jaroszynski, Dino Anthony; Sheng, Zheng-Ming; Manahan, Grace Gloria; Xia, Guoxing; Jamison, Steven; Hidding, Bernhard

2014-01-01T23:59:59.000Z

34

Spectroscopy of betatron radiation emitted from laser-produced wakefield accelerated electronsa...  

E-Print Network [OSTI]

laser facilities in which the nature divergence and total x-ray flux of the betatron radiation has been is able to discern changes of the betatron emission x-ray spec- trum with differing laser parametersSpectroscopy of betatron radiation emitted from laser-produced wakefield accelerated electronsa

Geddes, Cameron Guy Robinson

35

Scaling of the Longitudinal Electric Field and Transformer Ratio in a Nonlinear Plasma Wakefield Accelerator  

SciTech Connect (OSTI)

The scaling of the two important figures of merit, the transformer ratio T and the longitudinal electric field E{sub z}, with the peak drive-bunch current I{sub p}, in a nonlinear plasma wakefield accelerator is presented for the first time. The longitudinal field scales as I{sub P}{sup 0.623{+-}0.007}, in good agreement with nonlinear wakefield theory ({approx}I{sub P}{sup 0.5}), while the unloaded transformer ratio is shown to be greater than unity and scales weakly with the bunch current. The effect of bunch head erosion on both parameters is also discussed.

Blumenfeld, I.; /SLAC; Clayton, C.E.; /UCLA; Decker, F.J.; Hogan, M.J.; /SLAC; Huang, C.; /UCLA; Ischebeck, R.; Iverson, R.H.; /SLAC; Joshi, C.; /UCLA; Katsouleas, T.; /Southern California U.; Kirby, N.; /SLAC; Lu, W.; Marsh, K.A.; Mori, W.B.; /UCLA; Muggli, P.; Oz, E.; /Southern California U.; Siemann, R.H.; Walz, D.R.; /SLAC; Zhou, M.; /UCLA

2012-06-12T23:59:59.000Z

36

Control of seeding phase for a cascaded laser wakefield accelerator with gradient injection  

SciTech Connect (OSTI)

We demonstrated experimentally the seeding-phase control for a two-stage laser wakefield accelerator with gradient injection. By optimizing the seeding phase of electrons into the second stage, electron beams beyond 0.5 GeV with a 3% rms energy spread were produced over a short acceleration distance of ?2 mm. Peak energy of the electron beam was further extended beyond 1 GeV by lengthening the second acceleration stage to 5 mm. Time-resolved magnetic field measurements via magneto-optical Faraday polarimetry allowed us to monitor the processes of electron seeding and acceleration in the second stage.

Wang, Wentao; Li, Wentao; Liu, Jiansheng; Wang, Cheng; Chen, Qiang; Zhang, Zhijun; Qi, Rong; Leng, Yuxin; Liang, Xiaoyan; Liu, Yanqi; Lu, Xiaoming; Wang, Cheng; Li, Ruxin; Xu, Zhizhan [State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences (CAS), Shanghai 201800 (China)] [State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences (CAS), Shanghai 201800 (China)

2013-12-09T23:59:59.000Z

37

Injection and acceleration of electron bunch in a plasma wakefield produced by a chirped laser pulse  

SciTech Connect (OSTI)

An ultrashort laser pulse propagating in plasma can excite a nonlinear plasma wakefield which can trap and accelerate charged particles up to GeV. One-dimensional analysis of electron injection, trapping, and acceleration by different chirped pulses propagating in plasma is investigated numerically. In this paper, we inject electron bunches in front of the chirped pulses. It is indicated that periodical chirped laser pulse can trap electrons earlier than other pulses. It is shown that periodical chirped laser pulses lead to decrease the minimum momentum necessary to trap the electrons. This is due to the fact that periodical chirped laser pulses are globally much efficient than nonchirped pulses in the wakefield generation. It is found that chirped laser pulses could lead to much larger electron energy than that of nonchirped pulses. Relative energy spread has a lower value in the case of periodical chirped laser pulses.

Afhami, Saeedeh; Eslami, Esmaeil, E-mail: eeslami@iust.ac.ir [Department of Physics, Iran University of Science and Technology (IUST), Narmak, Tehran 16846-13114 (Iran, Islamic Republic of)

2014-06-15T23:59:59.000Z

38

Emittance and Current of Electrons Trapped in a Plasma Wakefield Accelerator  

SciTech Connect (OSTI)

In recent experiments plasma electrons became trapped in a plasma wakefield accelerator (PWFA). The transverse size of these trapped electrons on a downstream diagnostic yields an upper limit measurement of transverse normalized emittance divided by peak current, {epsilon}{sub N,{sub x}}/I. The lowest upper limit for {epsilon}{sub N,{sub x}}/I measured in the experiment is 1.3{center_dot}10{sup -10} m/A.

Kirby, N.; Blumenfeld, I.; Decker, F. J.; Hogan, M. J.; Ischebeck, R.; Iverson, R. H.; Siemann, R. H.; Walz, D. R. [Stanford Linear Accelerator Center, Stanford University, Stanford, California 94305 (United States); Clayton, C. E.; Huang, C.; Joshi, C.; Lu, W.; Marsh, K. A.; Mori, W. B.; Zhou, M. [University of California, Los Angeles, California 90095 (United States); Katsouleas, T.; Muggli, P.; Oz, E. [University of Southern California, Los Angeles, California 90089 (United States); Martins, S. [GoLP/IPFN, Instituto Superior Tecnico (Portugal)

2009-01-22T23:59:59.000Z

39

Spectrum bandwidth narrowing of Thomson scattering X-rays with energy chirped electron beams from laser wakefield acceleration  

SciTech Connect (OSTI)

We study incoherent Thomson scattering between an ultrashort laser pulse and an electron beam accelerated from a laser wakefield. The energy chirp effects of the accelerated electron beam on the final radiation spectrum bandwidth are investigated. It is found that the scattered X-ray radiation has the minimum spectrum width and highest intensity as electrons are accelerated up to around the dephasing point. Furthermore, it is proposed that the electron acceleration process inside the wakefield can be studied by use of 90 Thomson scattering. The dephasing position and beam energy chirp can be deduced from the intensity and bandwidth of the scattered radiation.

Xu, Tong; Chen, Min, E-mail: minchen@sjtu.edu.cn; Li, Fei-Yu; Yu, Lu-Le [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China)] [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Sheng, Zheng-Ming, E-mail: zmsheng@sjtu.edu.cn [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China) [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); SUPA, Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Zhang, Jie [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China) [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, CAS, Beijing 100190 (China)

2014-01-06T23:59:59.000Z

40

Proton-driven plasma wakefield acceleration: a path to the future of high-energy particle physics  

E-Print Network [OSTI]

New acceleration technology is mandatory for the future elucidation of fundamental particles and their interactions. A promising approach is to exploit the properties of plasmas. Past research has focused on creating large-amplitude plasma waves by injecting an intense laser pulse or an electron bunch into the plasma. However, the maximum energy gain of electrons accelerated in a single plasma stage is limited by the energy of the driver. Proton bunches are the most promising drivers of wakefields to accelerate electrons to the TeV energy scale in a single stage. An experimental program at CERN -- the AWAKE experiment -- has been launched to study in detail the important physical processes and to demonstrate the power of proton-driven plasma wakefield acceleration. Here we review the physical principles and some experimental considerations for a future proton-driven plasma wakefield accelerator.

Assmann, R; Bohl, T; Bracco, C; Buttenschon, B; Butterworth, A; Caldwell, A; Chattopadhyay, S; Cipiccia, S; Feldbaumer, E; Fonseca, R A; Goddard, B; Gross, M; Grulke, O; Gschwendtner, E; Holloway, J; Huang, C; Jaroszynski, D; Jolly, S; Kempkes, P; Lopes, N; Lotov, K; Machacek, J; Mandry, S R; McKenzie, J W; Meddahi, M; Militsyn, B L; Moschuering, N; Muggli, P; Najmudin, Z; Noakes, T C Q; Norreys, P A; Oz, E; Pardons, A; Petrenko, A; Pukhov, A; Rieger, K; Reimann, O; Ruhl, H; Shaposhnikova, E; Silva, L O; Sosedkin, A; Tarkeshian, R; Trines, R M G N; Tuckmantel, T; Vieira, J; Vincke, H; Wing, M; Xia, G

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Study of electron acceleration and x-ray radiation as a function of plasma density in capillary-guided laser wakefield accelerators  

SciTech Connect (OSTI)

Laser wakefield electron acceleration in the blow-out regime and the associated betatron X-ray radiation were investigated experimentally as a function of the plasma density in a configuration where the laser is guided. Dielectric capillary tubes were employed to assist the laser keeping self-focused over a long distance by collecting the laser energy around its central focal spot. With a 40 fs, 16 TW pulsed laser, electron bunches with tens of pC charge were measured to be accelerated to an energy up to 300 MeV, accompanied by X-ray emission with a peak brightness of the order of 10{sup 21} ph/s/mm{sup 2}/mrad{sup 2}/0.1%BW. Electron trapping and acceleration were studied using the emitted X-ray beam distribution to map the acceleration process; the number of betatron oscillations performed by the electrons was inferred from the correlation between measured X-ray fluence and beam charge. A study of the stability of electron and X-ray generation suggests that the fluctuation of X-ray emission can be reduced by stabilizing the beam charge. The experimental results are in good agreement with 3D particle-in-cell (PIC) simulation.

Ju, J.; Dpp, A.; Cros, B. [Laboratoire de Physique des Gaz et des Plasmas, CNRS-Universit Paris-Sud, 91405 Orsay (France)] [Laboratoire de Physique des Gaz et des Plasmas, CNRS-Universit Paris-Sud, 91405 Orsay (France); Svensson, K.; Genoud, G.; Wojda, F.; Burza, M.; Persson, A.; Lundh, O.; Wahlstrm, C.-G. [Department of Physics, Lund University, P.O. Box 118, S-22100 Lund (Sweden)] [Department of Physics, Lund University, P.O. Box 118, S-22100 Lund (Sweden); Ferrari, H. [Consejo Nacional de Investigaciones Cientficas y Tcnicas (CONICET) and CNEA-CAB (Argentina)] [Consejo Nacional de Investigaciones Cientficas y Tcnicas (CONICET) and CNEA-CAB (Argentina)

2013-08-15T23:59:59.000Z

42

SLAC-PUB-8352 E-157: A 1.4 Meterlong Plasma Wakefield Acceleration Experiment Using a  

E-Print Network [OSTI]

beam of 2 x 1010 electrons in a 0.65mm long bunch is propagated through a 1.4m long Lithium plasma gradients, much in excess of 1 GeV/m, but over rather small ( acceleration of electrons by plasma wakefield acceleration with gradients in excess of 100 MeV/m over

43

Laser-PlasmaWakefield Acceleration with Higher Order Laser Modes  

E-Print Network [OSTI]

Design considerations for a laser-plasma linear collider,"E.Esarey, and W.P.Leemans, "Free-electron laser driven bythe LBNL laser-plasma accelerator," in Proc. Adv. Acc. Con.

Geddes, C.G.R.

2011-01-01T23:59:59.000Z

44

Multi-bunch Plasma Wakefield Acceleration at ATF  

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

280 MeV1.4m, e- and e+ - ANL: 15 MeV30cm, >50% beam energy extracted - ATF: .6 MeVcm, focus and acceleration phases * Realizations require multi-bunches - Afterburner: 2 - NLC...

45

Two-Screen Method for Determining Electron Beam Energy and Deflection from Laser Wakefield Acceleration  

SciTech Connect (OSTI)

Laser Wakefield Acceleration (LWFA) experiments have been performed at the Jupiter Laser Facility, Lawrence Livermore National Laboratory. In order to unambiguously determine the output electron beam energy and deflection angle at the plasma exit, we have implemented a two-screen electron spectrometer. This system is comprised of a dipole magnet followed by two image plates. By measuring the electron beam deviation from the laser axis on each plate, both the energy and deflection angle at the plasma exit are determined through the relativistic equation of motion.

Pollock, B B; Ross, J S; Tynan, G R; Divol, L; Glenzer, S H; Leurent, V; Palastro, J P; Ralph, J E; Froula, D H; Clayton, C E; Marsh, K A; Pak, A E; Wang, T L; Joshi, C

2009-04-24T23:59:59.000Z

46

Self-Guided Laser Wakefield Acceleration beyond 1 GeV Using Ionization-Induced Injection  

SciTech Connect (OSTI)

The concepts of matched-beam, self-guided laser propagation and ionization-induced injection have been combined to accelerate electrons up to 1.45 GeV energy in a laser wakefield accelerator. From the spatial and spectral content of the laser light exiting the plasma, we infer that the 60 fs, 110 TW laser pulse is guided and excites a wake over the entire 1.3 cm length of the gas cell at densities below 1.5x10{sup 18} cm{sup -3}. High-energy electrons are observed only when small (3%) amounts of CO{sub 2} gas are added to the He gas. Computer simulations confirm that it is the K-shell electrons of oxygen that are ionized and injected into the wake and accelerated to beyond 1 GeV energy.

Clayton, C. E.; Joshi, C.; Lu, W.; Marsh, K. A.; Mori, W. B.; Pak, A.; Tsung, F. S. [Department of Electrical Engineering, University of California, Los Angeles, California 90095 (United States); Ralph, J. E.; Albert, F.; Glenzer, S. H.; Froula, D. H. [L-399, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); Fonseca, R. A.; Martins, S. F.; Silva, L. O. [GoLP/IPFN-LA, Instituto Superior Tecnico, Lisboa (Portugal); Pollock, B. B.; Ross, J. S. [L-399, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); MAE Department, University of California, San Diego, La Jolla, California 92093 (United States)

2010-09-03T23:59:59.000Z

47

Measurement of the Betatron Radiation Spectrum Coming From a Laser Wakefield Accelerator  

SciTech Connect (OSTI)

A Laser Wakefield Accelerator (LWFA) is under development at Lawrence Livermore National Laboratory (LLNL) to produce electron bunches with GeV class energy and energy spreads of a few-percent. The ultimate goal is to provide a bright and compact photon source for high energy density physics. The interaction of a high power (200 TW), short pulse (50 fs) laser with neutral He gas can generate quasi-monoenergetic electron beams at energies up to 1 GeV. The laser pulse can be self-guided over a dephasing length of 1 cm (for a plasma density of 1.5 x 10{sup 18} cm{sup -3}) overcoming the limitation of vacuum diffraction. Betatron radiation is emitted while the accelerated electrons undergo oscillations in the wakefield electrostatic field. Here we present electron spectra measurements with a two screen spectrometer allowing to fix the ambiguities due to electron deflections at the plasma exit. They have measured monoenergetic electron beams above 300 MeV. Furthermore a forward directed x-ray beam is observed. The measured betatron spectrum agrees well with the calculated spectrum in the synchrotron asymptotic limit (SAL) using the measured electron beam parameters.

Leurent, V; Michel, P; Clayton, C E; Pollock, B; Doeppner, T; Wang, T L; Ralph, J; Pak, A; Marsh, K; Joshi, C; Tynan, G R; Divol, L; Palastro, J P; Glenzer, S H; Froula, D H

2008-08-12T23:59:59.000Z

48

Enhanced dielectric-wall linear accelerator  

DOE Patents [OSTI]

A dielectric-wall linear accelerator is enhanced by a high-voltage, fast e-time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators. A high voltage is placed between the electrodes sufficient to stress the voltage breakdown of the insulator on command. A light trigger, such as a laser, is focused along at least one line along the edge surface of the laminated alternating layers of isolated conductors and insulators extending between the electrodes. The laser is energized to initiate a surface breakdown by a fluence of photons, thus causing the electrical switch to close very promptly. Such insulators and lasers are incorporated in a dielectric wall linear accelerator with Blumlein modules, and phasing is controlled by adjusting the length of fiber optic cables that carry the laser light to the insulator surface. 6 figs.

Sampayan, S.E.; Caporaso, G.J.; Kirbie, H.C.

1998-09-22T23:59:59.000Z

49

A Proposal for a 1 GeV Plasma-Wakefield Acceleration Experiment at SLAC T. Katsouleas, S. Lee, USC  

E-Print Network [OSTI]

, USC Los Angeles, CA 90089-0484 S. Chattopadhyay, W. Leemans, LBNL R. Assmann, P. Chen, F.J. Decker, R. Iverson, T. Kotseroglou, P. Raimondi, T. Raubenheimer, S. Rokni, R.H. Siemann, D. Walz, D. Whittum, SLAC C. Clayton, C. Joshi, K. Marsh, W. Mori, G. Wang, UCLA Abstract A plasma-based wakefield acceleration (PWFA

50

High-power radio frequency pulse generation and extration based on wakefield excited by an intense charged particle beam in dielectric-loaded waveguides.  

SciTech Connect (OSTI)

Power extraction using a dielectric-loaded (DL) waveguide is a way to generate high-power radio frequency (RF) waves for future particle accelerators, especially for two-beam-acceleration. In a two-beam-acceleration scheme, a low-energy, high-current particle beam is passed through a deceleration section of waveguide (decelerator), where the power from the beam is partially transferred to trailing electromagnetic waves (wakefields); then with a properly designed RF output coupler, the power generated in the decelerator is extracted to an output waveguide, where finally the power can be transmitted and used to accelerate another usually high-energy low-current beam. The decelerator, together with the RF output coupler, is called a power extractor. At Argonne Wakefield Accelerator (AWA), we designed a 7.8GHz power extractor with a circular DL waveguide and tested it with single electron bunches and bunch trains. The output RF frequency (7.8GHz) is the sixth harmonic of the operational frequency (1.3GHz) of the electron gun and the linac at AWA. In single bunch excitation, a 1.7ns RF pulse with 30MW of power was generated by a single 66nC electron bunch passing through the decelerator. In subsequent experiments, by employing different splitting-recombining optics for the photoinjector laser, electron bunch trains were generated and thus longer RF pulses could be successfully generated and extracted. In 16-bunch experiments, 10ns and 22ns RF pulses have been generated and extracted; and in 4-bunch experiments, the maximum power generated was 44MW with 40MW extracted. A 26GHz DL power extractor has also been designed to test this technique in the millimeter-wave range. A power level of 148MW is expected to be generated by a bunch train with a bunch spacing of 769ps and bunch charges of 20nC each. The arrangement for the experiment is illustrated in a diagram. Higher-order-mode (HOM) power extraction has also been explored in a dual-frequency design. By using a bunch train with a bunch spacing of 769ps and bunch charges of 50nC each, 90.4MW and 8.68MW of extracted power levels are expected to be reached at 20.8GHz and 35.1GHz, respectively. In order to improve efficiency in HOM power extraction, a novel technique has been proposed to suppress unintended modes.

Gao, F.; High Energy Physics; Illinois Inst. of Tech

2009-07-24T23:59:59.000Z

51

Self-truncated ionization injection and consequent monoenergetic electron bunches in laser wakefield acceleration  

SciTech Connect (OSTI)

The ionization-induced injection in laser wakefield acceleration has been recently demonstrated to be a promising injection scheme. However, the energy spread controlling in this mechanism remains a challenge because continuous injection in a mixed gas target is usually inevitable. Here, we propose that by use of certain initially unmatched laser pulses, the electron injection can be constrained to the very front region of the mixed gas target, typically in a length of a few hundreds micrometers determined by the laser self-focusing and the wake deformation. As a result, the produced electron beam has narrow energy spread and meanwhile contains tens of pC in charge. Both multidimensional simulations and theoretical analysis illustrate the effectiveness of this scheme.

Zeng, Ming; Zhang, Jie [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China)] [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Chen, Min, E-mail: minchen@sjtu.edu.cn [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China) [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Department of Mathematics, Institute of Natural Sciences, and MOE-LSC, Shanghai Jiao Tong University, Shanghai 20040 (China); Sheng, Zheng-Ming, E-mail: zmsheng@sjtu.edu.cn [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China) [Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); SUPA, Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Mori, Warren B. [University of California, Los Angeles, California 90095 (United States)] [University of California, Los Angeles, California 90095 (United States)

2014-03-15T23:59:59.000Z

52

Measurements of the critical power for self-injection of electrons in a laser wakefield accelerator  

SciTech Connect (OSTI)

A laser wakefield acceleration study has been performed in the matched, self-guided, blow-out regime where a 10 J, 60 fs laser produced 720 {+-} 50 MeV quasi-monoenergetic electrons with a divergence of {Delta}{theta} = 2.85 {+-} 0.15 mRad. While maintaining a nearly constant plasma density (3 x 10{sup 18} cm{sup -3}), a linear electron energy gain was measured from 100 MeV to 700 MeV when the plasma length was scaled from 3 mm to 8 mm. Absolute charge measurements indicate that self-injection occurs when P/P{sub cr} > 4 and saturates around 100 pC for P/P{sub cr} > 12. The results are compared with both analytical scalings and full 3D particle-in-cell simulations.

Froula, D H; Clayton, C E; Doppner, T; Fonseca, R A; Marsh, K A; Barty, C J; Divol, L; Glenzer, S H; Joshi, C; Lu, W; Martins, S F; Michel, P; Mori, W; Palastro, J P; Pollock, B B; Pak, A; Ralph, J E; Ross, J S; Siders, C; Silva, L O; Wang, T

2009-06-02T23:59:59.000Z

53

Frequency chirp and pulse shape effects in self-modulated laser wakefield accelerators  

SciTech Connect (OSTI)

The effect of asymmetric laser pulses on plasma wave excitation in a self-modulated laser wakefield accelerator is examined. Laser pulse shape and frequency chirp asymmetries, controlled experimentally in the laser system through a grating pair compressor, are shown to strongly enhance measured electron yields for certain asymmetries. It is shown analytically that a positive (negative) frequency chirp enhances (suppresses) the growth rate of the Raman forward scattering and near-forward Raman sidescatter instabilities, but is of minimal importance for the experimental parameters. Temporal laser pulse shapes with fast rise times (< plasma period) are shown to generate larger wakes (compared to slow rise time pulses) which seed the growth of the plasma wave, resulting in enhanced electron yield.

Schroeder, C.B.; Esarey, E.; Geddes, C.G.R.; Toth, Cs.; Shadwick, B.A.; van Tilborg, J.; Faure, J.; Leemans, W.P.

2002-11-07T23:59:59.000Z

54

E-Print Network 3.0 - all-dielectric electron accelerator Sample...  

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

Part II: Electron Storage Rings (2.5 weeks) 1. Beam... Linear Accelerators (2.5 weeks) 1. RF cavities 2. Wakefields and ... Source: Experimental High Energy Physics Collection:...

55

Electron diffraction using ultrafast electron bunches from a laser-wakefield accelerator at kHz repetition rate  

SciTech Connect (OSTI)

We show that electron bunches in the 50-100 keV range can be produced from a laser wakefield accelerator using 10 mJ, 35 fs laser pulses operating at 0.5 kHz. It is shown that using a solenoid magnetic lens, the electron bunch distribution can be shaped. The resulting transverse and longitudinal coherence is suitable for producing diffraction images from a polycrystalline 10 nm aluminum foil. The high repetition rate, the stability of the electron source, and the fact that its uncorrelated bunch duration is below 100 fs make this approach promising for the development of sub-100 fs ultrafast electron diffraction experiments.

He, Z.-H.; Thomas, A. G. R.; Nees, J. A.; Hou, B.; Krushelnick, K. [Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48106-2099 (United States)] [Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48106-2099 (United States); Beaurepaire, B.; Malka, V.; Faure, J. [Laboratoire d'Optique Appliquee, ENSTA-CNRS-Ecole Polytechnique, UMR 7639, 91761 Palaiseau (France)] [Laboratoire d'Optique Appliquee, ENSTA-CNRS-Ecole Polytechnique, UMR 7639, 91761 Palaiseau (France)

2013-02-11T23:59:59.000Z

56

VOLUME 82, NUMBER 6 P H Y S I C A L R E V I E W L E T T E R S 8 FEBRUARY 1999 Multimode Analysis of the Hollow Plasma Channel Wakefield Accelerator  

E-Print Network [OSTI]

. Two schemes of plasma excitation have been the focus of much of the work: the laser wakefield of the Hollow Plasma Channel Wakefield Accelerator C. B. Schroeder,1 D. H. Whittum,2 and J. S. Wurtele1,3 1 Berkeley National Laboratory, Berkeley, California 94720 (Received 1 April 1998) The hollow plasma channel

Wurtele, Jonathan

57

Silicon buried gratings for dielectric laser electron accelerators  

SciTech Connect (OSTI)

This paper describes design and simulations of dielectric laser electron accelerators that achieve Gigavolt-per-meter (GV/m) accelerating gradients and wide electron channels (>1??m). The accelerator design is based on a silicon buried grating structure that enables flexible phase synchronization, large electron channel fields, and low standing-wave ratio in the material. This design increases the accelerating gradients to more than double those of reported quartz grating accelerators, thereby reducing the input laser fluence by 60% for the same accelerating gradient. With a 100 fs pulsed laser, our silicon buried gratings can achieve a maximum gradient of 1.1 GV/m, indicating that these accelerators have potential for numerous electron-accelerator applications.

Chang, Chia-Ming, E-mail: cachang@alumni.stanford.edu [Bell Labs, Alcatel-Lucent, 791 Holmdel Road, Holmdel, New Jersey 07733 (United States); Solgaard, Olav [E. L. Ginzton Lab., Stanford University, Stanford, California 94305 (United States)

2014-05-05T23:59:59.000Z

58

Improvements to laser wakefield accelerated electron beam stability, divergence, and energy spread using three-dimensional printed two-stage gas cell targets  

SciTech Connect (OSTI)

High intensity, short pulse lasers can be used to accelerate electrons to ultra-relativistic energies via laser wakefield acceleration (LWFA) [T. Tajima and J. M. Dawson, Phys. Rev. Lett. 43, 267 (1979)]. Recently, it was shown that separating the injection and acceleration processes into two distinct stages could prove beneficial in obtaining stable, high energy electron beams [Gonsalves et al., Nat. Phys. 7, 862 (2011); Liu et al., Phys. Rev. Lett. 107, 035001 (2011); Pollock et al., Phys. Rev. Lett. 107, 045001 (2011)]. Here, we use a stereolithography based 3D printer to produce two-stage gas targets for LWFA experiments on the HERCULES laser system at the University of Michigan. We demonstrate substantial improvements to the divergence, pointing stability, and energy spread of a laser wakefield accelerated electron beam compared with a single-stage gas cell or gas jet target.

Vargas, M.; Schumaker, W.; He, Z.-H.; Zhao, Z.; Behm, K.; Chvykov, V.; Hou, B.; Krushelnick, K.; Maksimchuk, A.; Yanovsky, V.; Thomas, A. G. R., E-mail: agrt@umich.edu [Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2014-04-28T23:59:59.000Z

59

Engineering Prototype for a Compact Medical Dielectric Wall Accelerator  

Science Journals Connector (OSTI)

A compact accelerator system architecture based on the dielectric wall accelerator (DWA) for medical proton beam therapy has been developed by the Compact Particle Acceleration Corporation (CPAC). The major subsystems are a Radio Frequency Quadrupole (RFQ) injector linac a pulsed kicker to select the desired proton bunches and a DWA linear accelerator incorporating a high gradient insulator (HGI) with stacked Blumleins to produce the required acceleration energy. The Blumleins are switched with solid state laser?driven optical switches integrated into the Blumlein assemblies. Other subsystems include a high power pulsed laser fiber optic distribution system electrical charging system and beam diagnostics. An engineering prototype has been constructed and characterized and these results will be used within the next three years to develop an extremely compact 150 MeV system capable of modulating energy beam current and spot size on a shot?to?shot basis. This paper presents the details the engineering prototype experimental results and commercialization plans.

Anthony Zografos; Andy Hening; Vladimir Joshkin; Kevin Leung; Dave Pearson; Henry Pearce?Percy; Mario Rougieri; Yoko Parker; John Weir; Donald Blackfield; Yu?Jiuan Chen; Steven Falabella; Gary Guethlein; Brian Poole; Robert W. Hamm; Reinard Becker

2011-01-01T23:59:59.000Z

60

Dielectric-Lined High-Gradient Accelerator Structure  

SciTech Connect (OSTI)

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.

Jay L. Hirshfield

2012-04-24T23:59:59.000Z

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Plasma wakefields driven by an incoherent combination of laser pulses: a path towards high-average power laser-plasma accelerators  

SciTech Connect (OSTI)

he wakefield generated in a plasma by incoherently combining a large number of low energy laser pulses (i.e.,without constraining the pulse phases) is studied analytically and by means of fully-self-consistent particle-in-cell simulations. The structure of the wakefield has been characterized and its amplitude compared with the amplitude of the wake generated by a single (coherent) laser pulse. We show that, in spite of the incoherent nature of the wakefield within the volume occupied by the laser pulses, behind this region the structure of the wakefield can be regular with an amplitude comparable or equal to that obtained from a single pulse with the same energy. Wake generation requires that the incoherent structure in the laser energy density produced by the combined pulses exists on a time scale short compared to the plasma period. Incoherent combination of multiple laser pulses may enable a technologically simpler path to high-repetition rate, high-average power laser-plasma accelerators and associated applications.

Benedetti, C.; Schroeder, C.B.; Esarey, E.; Leemans, W.P.

2014-05-01T23:59:59.000Z

62

E-Print Network 3.0 - argonne wakefield accelerator Sample Search...  

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

Accelerator System (ATLAS) facility at Argonne. Pure samples of neptunium, americium and curium... InsIde ArgonneDirector:Americaneedstoreigniteinnovationecology'-Page2 ......

63

MeV-Energy X Rays from Inverse Compton Scattering with Laser-Wakefield Accelerated Electrons  

Science Journals Connector (OSTI)

We report the generation of MeV x rays using an undulator and accelerator that are both driven by the same 100-terawatt laser system. The laser pulse driving the accelerator and the scattering laser pulse are independently optimized to generate a high energy electron beam (>200??MeV) and maximize the output x-ray brightness. The total x-ray photon number was measured to be ?1107, the source size was 5???m, and the beam divergence angle was ?10??mrad. The x-ray photon energy, peaked at 1MeV (reaching up to 4MeV), exceeds the thresholds of fundamental nuclear processes (e.g., pair production and photodisintegration).

S. Chen; N. D. Powers; I. Ghebregziabher; C. M. Maharjan; C. Liu; G. Golovin; S. Banerjee; J. Zhang; N. Cunningham; A. Moorti; S. Clarke; S. Pozzi; D. P. Umstadter

2013-04-10T23:59:59.000Z

64

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

SciTech Connect (OSTI)

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.

Byer, Robert L.

2013-11-07T23:59:59.000Z

65

Terahertz radiation as a bunch diagnostic for laser-wakefield-accelerated electron bunches  

SciTech Connect (OSTI)

Experimental results are reported from two measurement techniques (semiconductor switching and electro-optic sampling) that allow temporal characterization of electron bunches produced by a laser-driven plasma-based accelerator. As femtosecond electron bunches exit the plasma-vacuum interface, coherent transition radiation (at THz frequencies) is emitted. Measuring the properties of this radiation allows characterization of the electron bunches. Theoretical work on the emission mechanism is presented, including a model that calculates the THz wave form from a given bunch profile. It is found that the spectrum of the THz pulse is coherent up to the 200 {micro}m thick crystal (ZnTe) detection limit of 4 THz, which corresponds to the production of sub-50 fs (rms) electron bunch structure. The measurements demonstrate both the shot-to-shot stability of bunch parameters that are critical to THz emission (such as total charge and bunch length), as well as femtosecond synchronization among bunch, THz pulse, and laser beam.

van Tilborg, Jeroen; Schroeder, Carl; Filip, Catalin; Toth, Csaba; Geddes, Cameron; Fubiani, Gwenael; Esarey, Eric; Leemans, Wim

2011-06-17T23:59:59.000Z

66

VOLUME 78, NUMBER 16 P H Y S I C A L R E V I E W L E T T E R S 21 APRIL 1997 Electron Acceleration by a Laser Wakefield in a Relativistically Self-Guided Channel  

E-Print Network [OSTI]

, x-ray lasers, and ultrahigh-gradient electron accelerators [2]. In the latter case, the field by a Laser Wakefield in a Relativistically Self-Guided Channel R. Wagner, S.-Y. Chen, A. Maksimchuk, and D-modulated laser wakefield is discussed. Above a power threshold, a relativistically self-guided channel from

Umstadter, Donald

67

A monolithic relativistic electron beam source based on a dielectric laser accelerator structure  

SciTech Connect (OSTI)

Work towards a monolithic device capable of producing relativistic particle beams within a cubic-centimeter is detailed. We will discuss the Micro-Accelerator Platform (MAP), an optical laser powered dielectric accelerator as the main building block of this chip-scale source along with a field enhanced emitter and a region for sub-relativistic acceleration.

McNeur, Josh; Carranza, Nestor; Travish, Gil; Yin Hairong; Yoder, Rodney [UCLA Dept. of Physics and Astronomy, Los Angeles, CA 90095 (United States); College of Physical Electronics, University of Electronic Science and Technology of China, Chengdu, Sichuan, 610054 (China); Manhattanville College, Physics Dept., 2900 Purchase St., Purchase, NY 10577 (United States)

2012-12-21T23:59:59.000Z

68

Generation of 500 MeV-1 GeV energy electrons from laser wakefield acceleration via ionization induced injection using CO{sub 2} mixed in He  

SciTech Connect (OSTI)

Laser wakefield acceleration of 500 MeV to 1 GeV electron bunches has been demonstrated using ionization injection in mixtures of 4% to 10% of CO{sub 2} in He. 80 TW laser pulses were propagated through 5 mm gas jet targets at electron densities of 0.4-1.5 Multiplication-Sign 10{sup 19}cm{sup -3}. Ionization injection led to lower density thresholds, a higher total electron charge, and an increased probability of producing electrons above 500 MeV in energy compared to self-injection in He gas alone. Electrons with GeV energies were also observed on a few shots and indicative of an additional energy enhancement mechanism.

Mo, M. Z.; Ali, A.; Fedosejevs, R. [Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta T6G 2V4 (Canada)] [Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta T6G 2V4 (Canada); Fourmaux, S.; Lassonde, P.; Kieffer, J. C. [INRS-EMT, Universite du Quebec, 1650 Lionel Boulet, Varennes, Quebec J3X 1S2 (Canada)] [INRS-EMT, Universite du Quebec, 1650 Lionel Boulet, Varennes, Quebec J3X 1S2 (Canada)

2013-04-01T23:59:59.000Z

69

Transverse Effect due to Short-range Resistive Wall Wakefield  

SciTech Connect (OSTI)

For accelerator designs with ultra short electron beams, beam dynamics study has to invoke the short-range wakefields. In this paper, we first obtain the short-range dipole mode resistive wall wakefield. Analytical approach is then developed to study the single bunch transverse beam dynamics due to this short-range resistive wall wake. The results are applied to the LCLS undulator.

Juhao Wu; Alex Chao; Jean Delayen

2007-06-18T23:59:59.000Z

70

Plasma acceleration from radio-frequency discharge in dielectric capillary A. Dunaevskya  

E-Print Network [OSTI]

Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543 Received 19 August 2005; accepted 22Plasma acceleration from radio-frequency discharge in dielectric capillary A. Dunaevskya Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540 Y. Raitses and N. J. Fisch Princeton

71

Plasma wakefields driven by an incoherent combination of laser pulses: a path towards high-average power laser-plasma accelerators  

E-Print Network [OSTI]

and W.P. Leemans, Phys. Plasmas 18, 083103 (2011). 34 C.IEEE Transactions on plasma science 36, 1790 (2008). 35 C.Plasma wakefields driven by an incoherent combination of

Benedetti, C

2014-01-01T23:59:59.000Z

72

Ultrafast Diagnostics for Electron Beams from Laser Plasma Accelerators  

E-Print Network [OSTI]

for Laser Plasma Accelerators," in this proceedings, 2010.Based Laser Wakefield Accelerator Electron Beam EnergyMotion in a Laser-Plasma Accelerator," in this proceedings,

Matlis, N. H.

2011-01-01T23:59:59.000Z

73

Results from Plasma Wakefield Experiments at FACET  

SciTech Connect (OSTI)

We report initial results of the Plasma Wakefield Acceleration (PWFA) Experiments performed at FACET - Facility for Advanced aCcelertor Experimental Tests at SLAC National Accelerator Laboratory. At FACET a 23 GeV electron beam with 1.8 x 10{sup 10} electrons is compressed to 20 {mu}m longitudinally and focused down to 10 {mu}m x 10 {mu}m transverse spot size for user driven experiments. Construction of the FACET facility completed in May 2011 with a first run of user assisted commissioning throughout the summer. The first PWFA experiments will use single electron bunches combined with a high density lithium plasma to produce accelerating gradients > 10 GeV/m benchmarking the FACET beam and the newly installed experimental hardware. Future plans for further study of plasma wakefield acceleration will be reviewed. The experimental hardware and operation of the plasma heat-pipe oven have been successfully commissioned. Plasma wakefield acceleration was not observed because the electron bunch density was insufficient to ionize the lithium vapor. The remaining commissioning time in summer 2011 will be dedicated to delivering the FACET design parameters for the experimental programs which will begin in early 2012. PWFA experiments require the shorter bunches and smaller transverse sizes to create the plasma and drive large amplitude wakefields. Low emittance and high energy will minimize head erosion which was found to be a limiting factor in acceleration distance and energy gain. We will run the PWFA experiments with the design single bunch conditions in early 2012. Future PWFA experiments at FACET are discussed in [5][6] and include drive and witness bunch production for high energy beam manipulation, ramped bunch to optimize tranformer ratio, field-ionized cesium plasma, preionized plasmas, positron acceleration, etc.. We will install a notch collimator for two-bunch operation as well as new beam diagnostics such as the X-band TCAV [7] to resolve the two bunches. With these new instruments and desired beam parameters in place next year, we will be able to complete the studies of plasma wakefield acceleration in the next few years.

Li, S.Z.; Clarke, C.I.; England, R.J.; Frederico, J.; Gessner, S.J.; Hogan, M.J.; Jobe, R.K.; Litos, M.D.; Walz, D.R.; /SLAC; Muggli, P.; /Munich, Max Planck Inst.; An, W.; Clayton, C.E.; Joshi, C.; Lu, W.; Marsh, K.A.; Mori, W.; Tochitsky, S.; /UCLA; Adli, E.; /U. Oslo

2011-12-13T23:59:59.000Z

74

An asymmetric emittance electron source for the GALAXIE dielectric-laser accelerator injector  

SciTech Connect (OSTI)

The GALAXIE project is a program to develop an all-optical, very high field accelerator and undulator integrated SASE FEL system based on dielectric laser-excited structures that support >GV/m fields. These structures are very wide in one direction to allow adequate charge given beam loading considerations, but also having small (subwavelength) apertures in the narrow direction. Such small vertical dimensions yield strict restrictions on the emittance in this direction, while no such constraint exists in the wide transverse direction. However, the overall beam brightness is restricted by the performance requirements on the FEL. To meet these demands, we are studying a very high field gun with a magnetized cathode, yielding a beam with angular momentum content. This beam is then subject to a skew-quad triplet that splits the emittances; this process is reversed to give a round beam after acceleration. This symmetric emittance beam avoids gain-degrading multiple-transverse-mode operation of the FEL, which also demands that the effects of the angular momentum in the beam be mitigated. In this paper we discuss the RF design of an X-band gun to be operated at {approx}200 MV/m peak field giving a 1 pC magnetized beam with unprecedented brightness. We examine the design of the focusing and skew-quad systems, investigating the associated beam dynamics and efficacy of emittance splitting.

Valloni, A.; Cahill, A.; Fukusawa, A.; Musumeci, P.; Spataro, B.; Yakub, A.; Rosenzweig, J. B. [Dept. of Physics and Astronomy, University of California, Los Angeles, 405 Hilgard Ave., Los Angeles, CA 90034 (United States); Accelerator Division, Laboratori Nazionali di Frascati (INFN-LNF), Via E. Fermi 40, Frascati (RM) 00044 (Italy); Dept. of Physics and Astronomy, University of California, Los Angeles, 405 Hilgard Ave., Los Angeles, CA 90034 (United States)

2012-12-21T23:59:59.000Z

75

Generation of wakefields by whistlers in spin quantum magnetoplasmas  

SciTech Connect (OSTI)

The excitation of electrostatic wakefields in a magnetized spin quantum plasma by the classical and the spin-induced ponderomotive force (CPF and SPF, respectively) due to whistler waves is reported. The nonlinear dynamics of the whistlers and the wakefields is shown to be governed by a coupled set of nonlinear Schroedinger and driven Boussinesq-like equations. It is found that the quantum force associated with the Bohm potential introduces two characteristic length scales, which lead to the excitation of multiple wakefields in a strongly magnetized dense plasma (with a typical magnetic field strength B{sub 0} or approx. 10{sup 9} T and particle density n{sub 0} > or approx. 10{sup 36} m{sup -3}), where the SPF strongly dominates over the CPF. In other regimes, namely, B{sub 0} < or approx. 10{sup 8} T and n{sub 0} < or approx. 10{sup 35} m{sup -3}, where the SPF is comparable to the CPF, a plasma wakefield can also be excited self-consistently with one characteristic length scale. Numerical results reveal that the wakefield amplitude is enhanced by the quantum tunneling effect; however, it is lowered by the external magnetic field. Under appropriate conditions, the wakefields can maintain high coherence over multiple plasma wavelengths and thereby accelerate electrons to extremely high energies. The results could be useful for particle acceleration at short scales, i.e., at nanometer and micrometer scales, in magnetized dense plasmas where the driver is the whistler wave instead of a laser or a particle beam.

Misra, A. P.; Brodin, G.; Marklund, M. [Department of Physics, Umeaa University, SE-901 87 Umeaa (Sweden); Shukla, P. K. [Department of Physics, Umeaa University, SE-901 87 Umeaa (Sweden); RUB International Chair, International Centre for Advanced Studies in Physical Sciences, Faculty of Physics and Astronomy, Ruhr University Bochum, D-44780 Bochum (Germany)

2010-12-15T23:59:59.000Z

76

Transverse wakefields due to asymmetric protrusions into a vacuum chamber  

Science Journals Connector (OSTI)

Abstract We analyze the effect of a wakefield caused by an asymmetric protrusion inside the accelerator vacuum chamber. The asymmetry leads to a transverse kick on the beam and an increase of the projected transverse beam emittance. Calculations are done for a model rectangular protrusion in a vacuum chamber of rectangular cross-section. Based on our analysis, numerical estimates are given for the SuperKEKB accelerator in KEK, Japan, and TLEP-W proposal at CERN.

Gennady Stupakov; Demin Zhou

2014-01-01T23:59:59.000Z

77

HEP Accelerator R&D Expertise | U.S. DOE Office of Science (SC...  

Office of Science (SC) Website

by university grants. As needed, promising concepts are tested at national laboratory test facilities, such as the Advanced Wakefield Accelerator (AWA) at ANL, the Accelerator...

78

E-Print Network 3.0 - accelerating beam stability Sample Search...  

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

(ARD) has the mission to develop accelerator Summary: between rf systems and particle beams, applications of control techniques to asses system stability... Wakefield Accelerator...

79

ONE GEV BEAM ACCELERATION IN A ONE METER LONG  

E-Print Network [OSTI]

ONE GEV BEAM ACCELERATION IN A ONE METER LONG PLASMA CELL A Proposal to the Stanford Linear. A single SLC bunch is used to both induce wakefields in the one meter long plasma and to witness that are needed to apply high-gradient plasma wakefield acceleration to large scale accelerators. The one meter

80

Laser guiding for GeV laserplasma accelerators  

Science Journals Connector (OSTI)

...plasma-beat-wave accelerator. Phys. Rev...Singhal2003Applications for nuclear phenomena generated...laser wakefield accelerators. Phys. Plasmas...crossing a plasma-vacuum boundary. Phys...laser wakefield accelerators. Phys. Plasmas...generated at a plasma-vacuum interface. Phys...

2006-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

ELECTRON INJECTION INTO CYCLIC ACCELERATOR USING  

E-Print Network [OSTI]

ELECTRON INJECTION INTO CYCLIC ACCELERATOR USING LASER WAKEFIELD ACCELERATION Ya. V. Getmanov, O. A acceleration #12;Storage ring with laser injection CYCLIC ACCELERATOR RF Electron injection The LWFA beam ­ accelerating light, 5 ­ accelerated electrons, 6 ­fast kicker - + accelerating laser pulse evaporatinglaser

82

An Accelerated Multiboson Algorithm for Coulomb Gases with Dynamical Dielectric Effects  

E-Print Network [OSTI]

A recent reformulation [1] of the problem of Coulomb gases in the presence of a dynamical dielectric medium showed that finite temperature simulations of such systems can be accomplished on the basis of completely local Hamiltonians on a spatial lattice by including additional bosonic fields. For large systems, the Monte Carlo algorithm proposed in Ref. [1] becomes inefficient due to a low acceptance rate for particle moves in a fixed background multiboson field. We show here how this problem can be circumvented by use of a coupled particle-multiboson update procedure that improves acceptance rates on large lattices by orders of magnitude. The method is tested on a one-component plasma with neutral dielectric particles for a variety of system sizes.

A. Duncan; R. D. Sedgewick

2006-02-15T23:59:59.000Z

83

Argonne Accelerator Institute  

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

Useful Links Useful Links Argonne National Laboratory Accelerator Sites Conferences Advanced Photon Source (APS) Argonne Wakefield Accelerator (AWA) Argonne Tandem Linear Accelerator System (ATLAS) High Energy Physics Division RIA (????) Link to JACoW (Joint Accelerator Conferences Website) Fermi National Accelerator Laboratory Fermilab-Argonne Collaboration Accelerator Physics Center Workshops Other Accelerator Institutes Energy Recovering Linacs Center for Advance Studies of Accelerators (Jefferson Labs) Center for Beam Physics (LBNL) Accelerator Test Facility (BNL) The Cockcroft Institute (Daresbury, UK) John Adams Institute (Rutherford, UK) ERL2009 to be held at Cornell ERL2007 ERL2005 DOE Laboratory with Accelerators Fermilab Stanford Linear Accelerator Center Brookhaven National Laboratory

84

Experimental demonstration of wakefield effects in a THz planar...  

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

energy chirp compensation * Self-wake energy modulation wakefield structure spectro meter Shaped beam energy chirped Shape + energy chirp energy change via self-wakefield...

85

Experimental demonstration of wakefield effects in a THz planar...  

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

ATF Users' Meetings, April 26 - 27, 2012 Wakefield Mapping wakefield structure spectro meter drive beam witness Experimental drive + witness visualization Spectrometer measurement...

86

Photocathode Studies at the Argonne Wakefield Accelerator  

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

Quantum Quantum Efficiency Photocathodes for the AWA High Energy Physics Division, ANL Zikri Yusof, Manoel Conde, Felipe Franchini Matt Virgo DOE Review April 26-27 2007 Energy Systems Division, ANL 2 PHOTOCATHODE REQUIREMENT FOR BUNCH TRAIN For the near future, creation of charge bunch train of 16 bunches in a single RF pulse 50 nC 16 micro pulses 5 eV Laser 10 mJ Want 50 nC in each charge microbunch. This is equal to ~ 3×10 11 electrons. * 10 mJ of laser energy per pulse; * Estimate 80% loss due to beam splitter, mirrors, etc.; * Beam is split into 16 micro pulses; * Number of photons in each micro pulse is ~1.5×10 14 . QE of photocathode to be able to supply that amount of charge: % 2 . 0 10 2 10 5 . 1 10 3 3 14 11 = × ≈ × × = - QE Need high QE photocathode - choose Cs 2 Te 770 ps 3 Cs 2 Te RECIPE

87

PLASMA WAKEFIELD ACCELERATION UTILIZING MULTIPLE ELECTRON BUNCHES  

E-Print Network [OSTI]

. Yakimenko, Brookhaven National Lab., Upton, NY W. D. Kimura, STI Optronics, Bellevue, WA Abstract We

Brookhaven National Laboratory

88

E-Print Network 3.0 - acceleration foran electron Sample Search...  

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

Physics and Fusion ; Physics 10 The Application of Radiation and Particle Beams from Laser Plasma Wakefield Accelerators to Oncology Summary: to recent improvements in...

89

E-Print Network 3.0 - accelerator applications university Sample...  

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

university Page: << < 1 2 3 4 5 > >> 1 The Application of Radiation and Particle Beams from Laser Plasma Wakefield Accelerators to Oncology Summary: The Application of...

90

How Accelerator Physicists Save Time | U.S. DOE Office of Science...  

Office of Science (SC) Website

much like the wake behind a boat. The wakefield accelerates the electron bunch, shown in green. Physicists rely on sophisticated computationally-intensive simulations in order to...

91

Electron Acceleration Experiments by Using a Density-tapered Capillary Plasma Source  

Science Journals Connector (OSTI)

We have developed a density-tapered capillary plasma source for high energy electron generation by using the laser wakefield acceleration, where the dephasing problem will be...

Suk, Hyyong; Nam, Inhyuk; Kim, Minseok; Lee, Seungwoo; Lee, Taehee

92

First Demonstration of Staged Laser Acceleration  

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

Laser Wakefield Acceleration Driven by a CO 2 Laser (STELLA-LW) W. D. Kimura ATF Users' Meeting Jan. 8, 2004 Work was supported by the U.S. Department of Energy, Grant Nos....

93

Electron Bunch Length Measurements in the E-167 Plasma Wakefield Experiment  

SciTech Connect (OSTI)

Bunch length is of prime importance to beam driven plasma wakefield acceleration experiments due to its inverse relationship to the amplitude of the accelerating wake. We present here a summary of work done by the E167 collaboration measuring the SLAC ultra-short bunches via autocorrelation of coherent transition radiation. We have studied material transmission properties and improved our autocorrelation traces using materials with better spectral characteristics.

Blumenfeld, I.; Auerbach, D.; Berry, M.; Clayton, C.E.; Decker, F.J.; Hogan, M.J.; Huang, Cheng-Kun; Ischebeck, R.; Iverson, R.; Johnson, D.; Joshi, C.; Katsouleas, T.; Kirby, N.; Lu, Wei; Marsh, K.A.; Mori, W.B.; Muggli, P.; Oz, E.; Siemann, R.H.; Walz, D.; Zacherl, W.; /SLAC /UCLA /Southern California U.

2007-03-27T23:59:59.000Z

94

Simulations of Jitter Coupling due to Wakefields in the FACET Linac  

SciTech Connect (OSTI)

Facilities for Accelerator Science and Experimental Test Beams (FACET) is a proposed facility at SLAC that would use the initial two-thirds of the linac to transport e{sup +} and e{sup -} beams to an experimental region. A principal use of this facility is to identify the optimum method for accelerating positrons in a beam driven plasma wakefield accelerator. To study this, a positron bunch, followed an RF-cycle later by an electron bunch, will be accelerated to an asymmetric chicane designed to move the positrons behind the electrons, and then on to the plasma wakefield test stand. A major focus of study was the coupling of jitter of the positron bunch to the electron bunch via linac wakes. Lucretia is a Matlab toolbox for the simulation of electron beam transport systems, capable of multi-bunch tracking and wakefield calculations. With the exception of the lack of support for tracking of electrons and positrons within a single bunch train, it was well suited to the jitter coupling studies. This paper describes the jitter studies, including modifications made to Lucretia to correctly simulate tracking of mixed-species bunch trains through a lattice of magnetic elements and EM wakes.

Molloy, Stephen

2009-10-30T23:59:59.000Z

95

Plasma-based Accelerator with Magnetic Compression  

SciTech Connect (OSTI)

Electron dephasing is a major gain-inhibiting effect in plasma-based accelerators. A novel method is proposed to overcome dephasing, in which the modulation of a modest (#24; O(10 kG)), axial, uniform magnetic field in the acceleration channel leads to densification of the plasma through magnetic compression, enabling direct, time-resolved control of the plasma wave properties. The methodology is broadly applicable and can be optimized to improve the leading acceleration approaches, including plasma beat-wave, plasma wakefield, and laser wakefield acceleration. The advantages of magnetic compression compared to other proposed schemes to overcome dephasing are identified.

Paul F. Schmit and Nathaniel J. Fisch

2012-06-28T23:59:59.000Z

96

Acceleration  

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

Acceleration Acceleration of porous media simulations on the Cray XE6 platform Kirsten M. Fagnan, Michael Lijewski, George Pau, Nicholas J. Wright Lawrence Berkeley National Laboratory 1 Cyclotron Road Berkeley, CA 94720 May 18, 2011 1 Introduction In this paper we investigate the performance of the Porous Media with Adaptive Mesh Refinment (PMAMR) code which was developed in the Center for Computational Science and Engineering at Lawrence Berkeley National Laboratory. This code is being used to model carbon sequestration and contaminant transport as part of the Advanced Simulation Capability for Environmental Management (ASCEM) project. The goal of the ASCEM project is to better understand and quantify flow and contaminant transport behavior in complex geological systems. It will also address the long-term performance of engineered components including cementitious materials in

97

Beam manipulation by self-wakefield at ATF  

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

Committee and the ATF Users' Meetings, April 26 - 27, 2012 Outline 1. Enhanced Transformer Ratio demonstration (wakefield mapping with the shaped beam) 2. Tunable beam energy...

98

Characterisation of electron beams from laser-driven particle accelerators  

SciTech Connect (OSTI)

The development, understanding and application of laser-driven particle accelerators require accurate measurements of the beam properties, in particular emittance, energy spread and bunch length. Here we report measurements and simulations showing that laser wakefield accelerators can produce beams of quality comparable to conventional linear accelerators.

Brunetti, E.; Manahan, G. G.; Shanks, R. P.; Islam, M. R.; Ersfeld, B.; Anania, M. P.; Cipiccia, S.; Issac, R. C.; Vieux, G.; Welsh, G. H.; Wiggins, S. M.; Jaroszynski, D. A. [Physics Department, University of Strathclyde, Glasgow G4 0NG (United Kingdom)

2012-12-21T23:59:59.000Z

99

Dielectric-wall linear accelerator with a high voltage fast rise time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators  

DOE Patents [OSTI]

A dielectric-wall linear accelerator is improved by a high-voltage, fast rise-time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators. A high voltage is placed between the electrodes sufficient to stress the voltage breakdown of the insulator on command. A light trigger, such as a laser, is focused along at least one line along the edge surface of the laminated alternating layers of isolated conductors and insulators extending between the electrodes. The laser is energized to initiate a surface breakdown by a fluence of photons, thus causing the electrical switch to close very promptly. Such insulators and lasers are incorporated in a dielectric wall linear accelerator with Blumlein modules, and phasing is controlled by adjusting the length of fiber optic cables that carry the laser light to the insulator surface. 12 figs.

Caporaso, G.J.; Sampayan, S.E.; Kirbie, H.C.

1998-10-13T23:59:59.000Z

100

Recent Advances in Plasma Acceleration  

SciTech Connect (OSTI)

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.

Hogan, Mark

2007-03-19T23:59:59.000Z

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Evolution of pulse shapes during compressor scans in a CPA system and control of electron acceleration in plasmas  

SciTech Connect (OSTI)

The skewness of the envelope function of 20 - 100 femtosecond Ti:sapphire laser pulses has been controlled by appropriate choice of the higher order special phase coefficients, and used for optimization of a plasma wakefield electron accelerator.

Toth, Csaba; de Groot, Joeri; van Tilborg, Jeroen; Geddes, Cameron G.R.; Faure, Jerome; Catravas, Palma; Schroeder, Carl; Shadwick, B.A.; Esarey, Eric; Leemans, Wim

2002-05-12T23:59:59.000Z

102

Wakefield Municipal Gas and Light Department - Residential Conservation  

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

Wakefield Municipal Gas and Light Department - Residential Wakefield Municipal Gas and Light Department - Residential Conservation Services Program Wakefield Municipal Gas and Light Department - Residential Conservation Services Program < Back Eligibility Residential Savings Category Home Weatherization Commercial Weatherization Sealing Your Home Heating & Cooling Commercial Heating & Cooling Cooling Appliances & Electronics Design & Remodeling Windows, Doors, & Skylights Manufacturing Commercial Lighting Lighting Water Heating Maximum Rebate Energy Audit Recommended Measures: $300 Programmable Thermostats: 2 units Program Info State Massachusetts Program Type Utility Rebate Program Rebate Amount Energy Audit Recommended Measures: 25% of total cost Refrigerators: $50 Clothes Washer: $50 Dishwasher: $50 Room AC: $50

103

Wakefields in SLAC linac collimators  

Science Journals Connector (OSTI)

When a beam travels near collimator jaws, it gets an energy loss and a transverse kick due to the backreaction of the beam field diffracted from the jaws. The effect becomes very important for an intense short bunch when a tight collimation of the background beam halo is required. In the Linac Coherent Light Source at SLAC a collimation system is used to protect the undulators from radiation due to particles in the beam halo. The halo is most likely formed from gun dark current or dark current in some of the accelerating sections. However, collimators are also responsible for the generation of wake fields. The wake field effect from the collimators not only brings an additional energy jitter and change in the trajectory of the beam, but it also rotates the beam on the phase plane, which consequently leads to a degradation of the performance of the Free Electron Laser at the Linac Coherent Light Source. In this paper, we describe a model of the wake field radiation in the SLAC linac collimators. We use the results of a numerical simulation to illustrate the model. Based on the model, we derive simple formulas for the bunch energy loss and the average kick. We also present results from experimental measurements that confirm our model.

A. Novokhatski; F.-J. Decker; H. Smith; M. Sullivan

2014-12-02T23:59:59.000Z

104

Modeling laser wakefield accelerators in a Lorentz boosted frame  

E-Print Network [OSTI]

on axis, beam average energy history and momentum spread aton the mean beam energy histories and on the longitudinalgave the same beam energy history within a few percents, and

Vay, J.-L.

2010-01-01T23:59:59.000Z

105

Modeling laser wakefield accelerators in a Lorentz boosted frame  

E-Print Network [OSTI]

on axis, beam average energy history and momentum spread aton the mean beam energy histories and on the lon- gitudinalgave the same beam energy history within a few percents, and

Vay, J.-L.

2010-01-01T23:59:59.000Z

106

PLASMA WAKEFIELD ACCELERATION EXPERIMENTS USING TWO SUBPICOSECOND ELECTRON BUNCHES*  

E-Print Network [OSTI]

. Yakimenko,3 1 University of Southern California, Los Angeles, CA, USA 2 STI Optronics, Inc., Bellevue, WA

Brookhaven National Laboratory

107

Tunable Electron Multibunch Production in Plasma Wakefield Accelerators  

E-Print Network [OSTI]

Synchronized, independently tunable and focused $\\mu$J-class laser pulses are used to release multiple electron populations via photo-ionization inside an electron-beam driven plasma wave. By varying the laser foci in the laboratory frame and the position of the underdense photocathodes in the co-moving frame, the delays between the produced bunches and their energies are adjusted. The resulting multibunches have ultra-high quality and brightness, allowing for hitherto impossible bunch configurations such as spatially overlapping bunch populations with strictly separated energies, which opens up a new regime for light sources such as free-electron-lasers.

Hidding, B; Wittig, G; Aniculaesei, C; Jaroszynski, D; McNeil, B W J; Campbell, L T; Islam, M R; Ersfeld, B; Sheng, Z -M; Xi, Y; Deng, A; Rosenzweig, J B; Andonian, G; Murokh, A; Hogan, M J; Bruhwiler, D L; Cormier, E

2014-01-01T23:59:59.000Z

108

The status and evolution of plasma wakefield particle accelerators  

Science Journals Connector (OSTI)

...respectively. This electric field will tend to focus the rest of the electron beam that resides...If the density length product of the plasma is large enough, the electron beam can focus within the plasma itself and indeed undergo multiple focusing...

2006-01-01T23:59:59.000Z

109

Physics of laser-driven plasma-based electron accelerators E. Esarey, C. B. Schroeder, and W. P. Leemans  

E-Print Network [OSTI]

Physics of laser-driven plasma-based electron accelerators E. Esarey, C. B. Schroeder, and W. P Laser-driven plasma-based accelerators, which are capable of supporting fields in excess of 100 GV/m, are reviewed. This includes the laser wakefield accelerator, the plasma beat wave accelerator, the self

Geddes, Cameron Guy Robinson

110

Modeling of 10 GeV-1 TeV laser-plasma accelerators using Lorentz boosted simulations  

E-Print Network [OSTI]

Modeling of 10 GeV-1 TeV laser-plasma accelerators using Lorentz boosted simulations J.-L. Vay,1,a-plasma wakefield accelerators in an optimal frame of reference [J.-L. Vay, Phys. Rev. Lett. 98, 130405 (2007 of plasma accelerators to very high energies and accurately models the laser evolution and the accelerated

Geddes, Cameron Guy Robinson

111

Beam Coupling to Optical Scale Accelerating Structures  

SciTech Connect (OSTI)

Current research efforts into structure based laser acceleration of electrons utilize beams from standard RF linacs. These beams must be coupled into very small structures with transverse dimensions comparable to the laser wavelength. To obtain decent transmission, a permanent magnet quadrupole (PMQ) triplet with a focusing gradient of 560 T/m is used to focus into the structure. Also of interest is the induced wakefield from the structure, useful for diagnosing potential accelerator structures or as novel radiation sources.

Sears, C.M.; Byer, R.L.; Colby, E.R.; Cowan, B.M.; Ischebeck, R.; Lincoln, M.R.; Siemann, R.H.; Spencer, J.E.; /SLAC; Plettner, T.; /Stanford U., Phys. Dept.

2007-03-27T23:59:59.000Z

112

Beam Coupling to Optical Scale Accelerating Structures  

SciTech Connect (OSTI)

Current research efforts into structure based laser acceleration of electrons utilize beams from standard RF linacs. These beams must be coupled into very small structures with transverse dimensions comparable to the laser wavelength. To obtain decent transmission, a permanent magnet quadrupole (PMQ) triplet with a focusing gradient of 560 T/m is used to focus into the structure. Also of interest is the induced wakefield from the structure, useful for diagnosing potential accelerator structures or as novel radiation sources.

Sears, Christopher M. S.; Colby, Eric R.; Cowan, Benjamin M.; Ischebeck, Rasmus; Lincoln, Melissa R.; Siemann, Robert H.; Spencer, James E. [Stanford Linear Accelerator Center, Menlo Park, CA 94025 (United States); Byer, Robert L.; Plettner, Tomas [Stanford University, Stanford, CA 94305 (United States)

2006-11-27T23:59:59.000Z

113

AUGMENTING COMPUTER MUSIC WITH JUST-IN-TIME COMPILATION Wesley Smith, Graham Wakefield  

E-Print Network [OSTI]

AUGMENTING COMPUTER MUSIC WITH JUST-IN-TIME COMPILATION Wesley Smith, Graham Wakefield University of California Santa Barbara Media Arts and Technology whsmith|wakefield@mat.ucsb.edu ABSTRACT We discuss

California at Santa Barbara, University of

114

Advanced Accelerator Concepts Workshop  

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

acceleration at the BNL-ATF Thomas Marshall GeVm WAKE FIELDS GENERATED BY A TRAIN OF pC, FEMTOSECOND BUNCHES IN A PLANAR DIELECTRIC MICROSTRUCTURE Changbiao Wang GeVm...

115

RF cavity using liquid dielectric for tuning and cooling  

DOE Patents [OSTI]

A system for accelerating particles includes an RF cavity that contains a ferrite core and a liquid dielectric. Characteristics of the ferrite core and the liquid dielectric, among other factors, determine the resonant frequency of the RF cavity. The liquid dielectric is circulated to cool the ferrite core during the operation of the system.

Popovic, Milorad (Warrenville, IL); Johnson, Rolland P. (Newport News, VA)

2012-04-17T23:59:59.000Z

116

Town of Wakefield, Massachusetts (Utility Company) | Open Energy  

Open Energy Info (EERE)

Wakefield Wakefield Place Massachusetts Utility Id 19979 Utility Location Yes Ownership M NERC Location NPCC NERC NPCC Yes Activity Buying Transmission Yes Activity Distribution Yes Activity Retail Marketing Yes Activity Bundled Services Yes References EIA Form EIA-861 Final Data File for 2010 - File1_a[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Utility Rate Schedules Grid-background.png Commercial Rate B Commercial Domestic Electric Rate A Residential Power Rate C Industrial Average Rates Residential: $0.1510/kWh Commercial: $0.1410/kWh Industrial: $0.1240/kWh References ↑ "EIA Form EIA-861 Final Data File for 2010 - File1_a" Retrieved from "http://en.openei.org/w/index.php?title=Town_of_Wakefield,_Massachusetts_(Utility_Company)&oldid=41183

117

Town of Wakefield, Virginia (Utility Company) | Open Energy Information  

Open Energy Info (EERE)

Wakefield, Virginia (Utility Company) Wakefield, Virginia (Utility Company) Jump to: navigation, search Name Town of Wakefield Place Virginia Utility Id 19978 Utility Location Yes Ownership M NERC Location SERC NERC SERC Yes Activity Distribution Yes References EIA Form EIA-861 Final Data File for 2010 - File1_a[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Utility Rate Schedules Grid-background.png Commercial Commercial Large Service Demand Industrial Out Town Residential Elec Residential Residential Residential Small Commercial Demand Commercial Average Rates Residential: $0.0855/kWh Commercial: $0.0855/kWh References ↑ "EIA Form EIA-861 Final Data File for 2010 - File1_a" Retrieved from

118

Physics of Laser-driven plasma-based acceleration  

SciTech Connect (OSTI)

The physics of plasma-based accelerators driven by short-pulse lasers is reviewed. This includes the laser wake-field accelerator, the plasma beat wave accelerator, the self-modulated laser wake-field accelerator, and plasma waves driven by multiple laser pulses. The properties of linear and nonlinear plasma waves are discussed, as well as electron acceleration in plasma waves. Methods for injecting and trapping plasma electrons in plasma waves are also discussed. Limits to the electron energy gain are summarized, including laser pulse direction, electron dephasing, laser pulse energy depletion, as well as beam loading limitations. The basic physics of laser pulse evolution in underdense plasmas is also reviewed. This includes the propagation, self-focusing, and guiding of laser pulses in uniform plasmas and plasmas with preformed density channels. Instabilities relevant to intense short-pulse laser-plasma interactions, such as Raman, self-modulation, and hose instabilities, are discussed. Recent experimental results are summarized.

Esarey, Eric; Schroeder, Carl B.

2003-06-30T23:59:59.000Z

119

Measurements of Collimator Wakefields at End Station A  

SciTech Connect (OSTI)

The angular deflection of a 28.5 GeV electron beam passing off-axis between the jaws of a collimator, generating a transverse wakefield, were measured in End Station A (ESA) at SLAC. In total, fifteen different configurations of collimator geometry and material were tested: some were chosen for compatibility with previous measurements while others served to study the effect of geometry and taper angles (geometrical contribution to the wakefield) and the effect of the material resistivity (resistive contribution) to the imparted kick. This paper summarises the last update of preliminary experimental results before they are finalised. The reconstructed kick factor is compared to analytical calculations and simulations.

Fernandez-Hernando, J.L.; /Daresbury; Molloy, S.; /SLAC; Smith, J.D.A.; /Cockcroft Inst. Accel. Sci. Tech.; Watson, Nigel Keith; /Birmingham U.

2011-11-01T23:59:59.000Z

120

Studies of Intense Laser Propagation in Channels for Extended Length Plasma Accelerators  

E-Print Network [OSTI]

. Wurtele, G. Shvets Massachusetts Institute of Technology, Cambridge, MA 02139 Abstract Progress profile. That is, n0(y) = 0 for y a In this section we consider the more that the wakefield accelerator scheme can be effective, but only if the beam load is placed on the first accelerating

Wurtele, Jonathan

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Submillimeter-resolution radiography of shielded structures with laser-accelerated electron beams  

E-Print Network [OSTI]

Submillimeter-resolution radiography of shielded structures with laser-accelerated electron beams (Received 24 March 2010; published 14 October 2010) We investigate the use of energetic electron beams beam (with energy >100 MeV) was generated by the process of laser-wakefield acceleration through

Umstadter, Donald

122

Shielding effect and wakefield pattern of a moving test charge in a non-Maxwellian dusty plasma  

SciTech Connect (OSTI)

By using the Vlasov-Poisson equations, we calculate an expression for the electrostatic potential caused by a test charge in an unmagnetized non-Maxwellian dusty plasma, whose constituents are the superthermal hot-electrons, the mobile cold-electrons with a neutralizing background of cold ions, and charge fluctuating isolated dust grains. The superthermality effects due to hot electrons not only modify the dielectric constant of the electron-acoustic waves but also significantly affect the electrostatic potential. The latter can be decomposed into the Debye-Hckel and oscillatory wake potentials. Analytical and numerical results reveal that the Debye-Hckel and wakefield potentials converge to the Maxwellian case for large values of superthermality parameter. Furthermore, the plasma parameters play a vital role in the formation of shielding and wakefield pattern in a two-electron temperature plasma. The present results should be important for laboratory and space dusty plasmas, where hot-electrons can be assumed to follow the non-Maxwellian distribution function.

Ali, S. [National Centre for Physics (NCP), Quaid-e-Azam University Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan)] [National Centre for Physics (NCP), Quaid-e-Azam University Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan); Khan, S. [National Centre for Physics (NCP), Quaid-e-Azam University Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan) [National Centre for Physics (NCP), Quaid-e-Azam University Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan); Department of Physics, Gomal University, Dera Ismail Khan 29050 (Pakistan)

2013-07-15T23:59:59.000Z

123

USING LUA FOR AUDIOVISUAL COMPOSTION Graham Wakefield Wesley Smith  

E-Print Network [OSTI]

USING LUA FOR AUDIOVISUAL COMPOSTION Graham Wakefield Wesley Smith University of California Santa Barbara Media Arts and Technology Program Santa Barbara, California, USA ABSTRACT In this paper, we/MSP/Jitter [27], PureData [19], etc.) are popular choices for composing interactive digital media works because

California at Santa Barbara, University of

124

Cushman & Wakefield Environmental Challenge | ENERGY STAR Buildings &  

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

Cushman & Wakefield Environmental Challenge Cushman & Wakefield Environmental Challenge Secondary menu About us Press room Contact Us Portfolio Manager Login Facility owners and managers Existing buildings Commercial new construction Industrial energy management Small business Service providers Service and product providers Verify applications for ENERGY STAR certification Design commercial buildings Energy efficiency program administrators Commercial and industrial program sponsors Associations State and local governments Federal agencies Tools and resources Training In this section How can we help you? Build an energy program Improve building and plant performance Earn the ENERGY STAR and other recognition Benchmark energy use ENERGY STAR in action Communicate and educate ENERGY STAR communications toolkit Bring Your Green to Work with ENERGY STAR

125

High-gradient compact linear accelerator  

DOE Patents [OSTI]

A high-gradient linear accelerator comprises a solid-state stack in a vacuum of five sets of disc-shaped Blumlein modules each having a center hole through which particles are sequentially accelerated. Each Blumlein module is a sandwich of two outer conductive plates that bracket an inner conductive plate positioned between two dielectric plates with different thicknesses and dielectric constants. A third dielectric core in the shape of a hollow cylinder forms a casing down the series of center holes, and it has a dielectric constant different that the two dielectric plates that sandwich the inner conductive plate. In operation, all the inner conductive plates are charged to the same DC potential relative to the outer conductive plates. Next, all the inner conductive plates are simultaneously shorted to the outer conductive plates at the outer diameters. The signal short will propagate to the inner diameters at two different rates in each Blumlein module. A faster wave propagates quicker to the third dielectric core across the dielectric plates with the closer spacing and lower dielectric constant. When the faster wave reaches the inner extents of the outer and inner conductive plates, it reflects back outward and reverses the field in that segment of the dielectric core. All the field segments in the dielectric core are then in unipolar agreement until the slower wave finally propagates to the third dielectric core across the dielectric plates with the wider spacing and higher dielectric constant. During such unipolar agreement, particles in the core are accelerated with gradients that exceed twenty megavolts per meter.

Carder, Bruce M. (205 Rogue River Hwy., Gold Hill, OR 97525)

1998-01-01T23:59:59.000Z

126

High-gradient compact linear accelerator  

DOE Patents [OSTI]

A high-gradient linear accelerator comprises a solid-state stack in a vacuum of five sets of disc-shaped Blumlein modules each having a center hole through which particles are sequentially accelerated. Each Blumlein module is a sandwich of two outer conductive plates that bracket an inner conductive plate positioned between two dielectric plates with different thicknesses and dielectric constants. A third dielectric core in the shape of a hollow cylinder forms a casing down the series of center holes, and it has a dielectric constant different that the two dielectric plates that sandwich the inner conductive plate. In operation, all the inner conductive plates are charged to the same DC potential relative to the outer conductive plates. Next, all the inner conductive plates are simultaneously shorted to the outer conductive plates at the outer diameters. The signal short will propagate to the inner diameters at two different rates in each Blumlein module. A faster wave propagates quicker to the third dielectric core across the dielectric plates with the closer spacing and lower dielectric constant. When the faster wave reaches the inner extents of the outer and inner conductive plates, it reflects back outward and reverses the field in that segment of the dielectric core. All the field segments in the dielectric core are then in unipolar agreement until the slower wave finally propagates to the third dielectric core across the dielectric plates with the wider spacing and higher dielectric constant. During such unipolar agreement, particles in the core are accelerated with gradients that exceed twenty megavolts per meter. 10 figs.

Carder, B.M.

1998-05-26T23:59:59.000Z

127

Excitation of two-dimensional plasma wakefields by trains of equidistant particle bunches  

SciTech Connect (OSTI)

Nonlinear effects responsible for elongation of the plasma wave period are numerically studied with the emphasis on two-dimensionality of the wave. The limitation on the wakefield amplitude imposed by detuning of the wave and the driver is found.

Lotov, K. V. [Budker Institute of Nuclear Physics SB RAS, 630090 Novosibirsk, Russia and Novosibirsk State University, 630090 Novosibirsk (Russian Federation)] [Budker Institute of Nuclear Physics SB RAS, 630090 Novosibirsk, Russia and Novosibirsk State University, 630090 Novosibirsk (Russian Federation)

2013-08-15T23:59:59.000Z

128

Laser wakefield simulation using a speed-of-light frame envelope model  

E-Print Network [OSTI]

Laser wakefield simulation using a speed-of-light frame envelope model B. Cowan , D. Bruhwiler , E. By propagating the laser envelope in a frame moving at the speed of light, dispersive errors can be avoided

Geddes, Cameron Guy Robinson

129

Cushman & Wakefields Client Solutions Group presents:  

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

OCTOBER 2009 OCTOBER 2009 Updated January 2010 A CALL TO ACTION TO IMPROVE THE ENVIRONMENTAL EFFICIENCY OF CUSHMAN &WAKEFIELD'S MANAGED PROPERTIES Take the C&W Environmental Challenge and help us find out: * Who can quantify improvements in environmental performance over time? * Who can take environmental performance to the next level? * Which buildings are the highest performers across C&W managed portfolio? WHAT IS THE C&W ENVIRONMENTAL CHALLENGE? WHY PARTICIPATE? IMPROVE YOUR BOTTOM LINE: Increased energy and water efficiency, and reduced waste in commercial real estate can reduce operating expenses and increase property asset value. DO YOUR PART TO ADDRESS CLIMATE CHANGE: Commercial buildings generate about 17% of total greenhouse gas emissions.

130

Accelerators and the Accelerator Community  

E-Print Network [OSTI]

of electrostatic accelerators, while Ernest O. Lawrence (CBP 820 LBNL TBA ACCELERATORS ANDTHE ACCELERATOR COMMUNITY 1 ANDREW SESSLER Lawrence Berkeley

Malamud, Ernest

2009-01-01T23:59:59.000Z

131

Accelerators, Electrodynamics  

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

Science and Innovation Capabilities Accelerators, Electrodynamics science-innovationassetsimagesicon-science.jpg Accelerators, Electrodynamics National security depends...

132

Resonant dielectric metamaterials  

SciTech Connect (OSTI)

A resonant dielectric metamaterial comprises a first and a second set of dielectric scattering particles (e.g., spheres) having different permittivities arranged in a cubic array. The array can be an ordered or randomized array of particles. The resonant dielectric metamaterials are low-loss 3D isotropic materials with negative permittivity and permeability. Such isotropic double negative materials offer polarization and direction independent electromagnetic wave propagation.

Loui, Hung; Carroll, James; Clem, Paul G; Sinclair, Michael B

2014-12-02T23:59:59.000Z

133

2012 SG Peer Review - Day 2 Panel Discussion: Matt Wakefield, EPRI  

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

Matt Wakefield Matt Wakefield Senior Program Manager, Smart Grid June 7, 2012 Overview & Industry Coordination of EPRI IntelliGrid & Security Research & Smart Grid Demonstrations 2 © 2012 Electric Power Research Institute, Inc. All rights reserved. IntelliGrid Program Information & Communication Technologies (ICT) to Enable..... The IntelliGrid Program conducts research, development and demonstrations on the Information and Communications Technologies (ICT) that Enable Smart Grid applications IntelliGrid * Transmission * Distribution * End-Use (AMI/DR) 3 © 2012 Electric Power Research Institute, Inc. All rights reserved. * Reliability and performance characteristics the various technology

134

Control of focusing forces and emittances in plasma-based accelerators using near-hollow plasma channels  

SciTech Connect (OSTI)

A near-hollow plasma channel, where the plasma density in the channel is much less than the plasma density in the walls, is proposed to provide independent control over the focusing and accelerating forces in a plasma accelerator. In this geometry the low density in the channel contributes to the focusing forces, while the accelerating fields are determined by the high density in the channel walls. The channel also provides guiding for intense laser pulses used for wakefield excitation. Both electron and positron beams can be accelerated in a nearly symmetric fashion. Near-hollow plasma channels can effectively mitigate emittance growth due to Coulomb scattering for high energy physics applications.

Schroeder, Carl; Esarey, Eric; Benedetti, Carlo; Leemans, Wim

2013-08-06T23:59:59.000Z

135

Multi-GeV Energy Gain in a Plasma-Wakefield Accelerator M. J. Hogan,1  

E-Print Network [OSTI]

. Katsouleas,3 P. Krejcik,1 W. Lu,2 K. A. Marsh,2 W. B. Mori,2 P. Muggli,3 C. L. O'Connell,1 E. Oz,3 R. H,2 F. J. Decker,1 S. Deng,3 P. Emma,1 C. Huang,2 R. H. Iverson,1 D. K. Johnson,2 C. Joshi,2 T regime is reached when the electron bunch density nb N=23=2z2 r is greater than the plasma density np

Jalali. Bahram

136

Study of electron trapping by a transversely ellipsoidal bubble in the laser wake-field acceleration  

SciTech Connect (OSTI)

We present electron trapping in an ellipsoidal bubble which is not well explained by the spherical bubble model by [Kostyukov et al., Phys. Rev. Lett. 103, 175003 (2009)]. The formation of an ellipsoidal bubble, which is elongated transversely, frequently occurs when the spot size of the laser pulse is large compared to the plasma wavelength. First, we introduce the relation between the bubble size and the field slope inside the bubble in longitudinal and transverse directions. Then, we provide an ellipsoidal model of the bubble potential and investigate the electron trapping condition by numerical integration of the equations of motion. We found that the ellipsoidal model gives a significantly less restrictive trapping condition than that of the spherical bubble model. The trapping condition is compared with three-dimensional particle-in-cell simulations and the electron trajectory in test potential simulations.

Cho, Myung-Hoon [School of Natural Science, UNIST, BanYeon-Ri 100, Ulju-gun, Ulsan 689-798 (Korea, Republic of)] [School of Natural Science, UNIST, BanYeon-Ri 100, Ulju-gun, Ulsan 689-798 (Korea, Republic of); Kim, Young-Kuk; Hur, Min Sup [School of Electrical and Computer Engineering, UNIST, BanYeon-Ri 100, Ulju-gun, Ulsan 689-798 (Korea, Republic of)] [School of Electrical and Computer Engineering, UNIST, BanYeon-Ri 100, Ulju-gun, Ulsan 689-798 (Korea, Republic of)

2013-09-15T23:59:59.000Z

137

EXPERIMENTAL RESULTS OF A PLASMA WAKEFIELD ACCELERATOR USING MULTIPLE ELECTRON BUNCHES  

E-Print Network [OSTI]

. Yakimenko, BNL, Upton, NY, USA W. D. Kimura STI Optronics, Inc., Bellevue, WA, USA Abstract We present some

Brookhaven National Laboratory

138

SciTech Connect: Beam Matching to a Plasma Wakefield Accelerator...  

Office of Scientific and Technical Information (OSTI)

the E-164X PWFA experiments at SLAC. Authors: Marsh, K.A.; Clayton, C.E.; Huang, C.; Johnson, D.K.; Joshi, C.; Lu, W.; Mori, W.B.; Zhou, M.; UCLA; Barnes, C.D.; Decker, F.J.;...

139

Visual Exploration of Turbulent Combustion and Laser-Wakefield Accelerator Simulations  

E-Print Network [OSTI]

hydrogen flames under different levels of turbulence ­ Lean combustion reduces emissions Important-dependent, difficult to characterize) · Scientific Goal: ­ Understanding the temporal evolution of burning cells Simulations 4 Feature Tracking in Combustion Simulations · Isotherm represents "flame surface" · Fuel

140

Betatron radiation based measurement of the electron-beam size in a wakefield accelerator  

SciTech Connect (OSTI)

We present a spatial and spectral characterization of a laser-plasma based betatron source which allows us to determine the betatron oscillation amplitude of the electrons which decreases with increasing electron energies. Due to the observed oscillation amplitude and the independently measured x-ray source size of (1.8{+-}0.3){mu}m we are able to estimate the electron bunch diameter to be (1.6{+-}0.3){mu}m.

Schnell, Michael; Saevert, Alexander; Reuter, Maria [Institut fuer Optik und Quantenelektronik, Friedrich- Schiller- Universitaet, Jena (Germany); and others

2012-07-09T23:59:59.000Z

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Frequency chirp and pulse shape effects in self-modulated laser wakefield acceleratorsa...  

E-Print Network [OSTI]

laser-plasma-based harmonic generation,2 x-ray lasers,3 and laser-driven inertial confinement fusionFrequency chirp and pulse shape effects in self-modulated laser wakefield acceleratorsa... C. B Received 7 November 2002; accepted 20 January 2003 The effect of asymmetric laser pulses on plasma wave

Geddes, Cameron Guy Robinson

142

Monte Carlo Characterization of a Pulsed Laser-Wakefield Driven Monochromatic  

E-Print Network [OSTI]

Monte Carlo Characterization of a Pulsed Laser-Wakefield Driven Monochromatic X-Ray Source S. D determination of the incident X-ray energy by using unfolding techniques. I. INTRODUCTION HE Diocles laser light from the same laser system, producing monochromatic X-rays with energy and spectral width

Umstadter, Donald

143

LuaAV: Extensibility and Heterogeneity for Audiovisual Graham WAKEFIELD and Wesley SMITH and Charles ROBERTS  

E-Print Network [OSTI]

LuaAV: Extensibility and Heterogeneity for Audiovisual Computing Graham WAKEFIELD and Wesley SMITH and Charles ROBERTS Media Arts and Technology, University of California Santa Barbara Santa Barbara, CA 93110 providing the flexibility and temporal accuracy demanded by interactive audio-visual media. Code generation

California at Santa Barbara, University of

144

LASER ACCELERATORS  

E-Print Network [OSTI]

UNIVERSITY OF CALIFORNIA Accelerator & Fusion Researchat the 1983 Particle Accelerator Conference, Santa Fe, NM,March 21-23, 1983 LASER ACCELERATORS A.M. Sessler TWO-WEEK

Sessler, A.M.

2008-01-01T23:59:59.000Z

145

Production, Characterization, and Acceleration of Optical Microbunches  

SciTech Connect (OSTI)

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.

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

2008-06-20T23:59:59.000Z

146

Generation of electron beams from a laser-based advanced accelerator at Shanghai Jiao Tong University  

E-Print Network [OSTI]

At Shanghai Jiao Tong University, we have established a research laboratory for advanced acceleration research based on high-power lasers and plasma technologies. In a primary experiment based on the laser wakefield acceleration (LWFA) scheme, multi-hundred MeV electron beams having a reasonable quality are generated using 20-40 TW, 30 femtosecond laser pulses interacting independently with helium, neon, nitrogen and argon gas jet targets. The laser-plasma interaction conditions are optimized for stabilizing the electron beam generation from each type of gas. The electron beam pointing angle stability and divergence angle as well as the energy spectra from each gas jet are measured and compared.

Elsied, Ahmed M M; Li, Song; Mirzaie, Mohammad; Sokollik, Thomas; Zhang, Jie

2014-01-01T23:59:59.000Z

147

Thermally switchable dielectrics  

DOE Patents [OSTI]

Precursor polymers to conjugated polymers, such as poly(phenylene vinylene), poly(poly(thiophene vinylene), poly(aniline vinylene), and poly(pyrrole vinylene), can be used as thermally switchable capacitor dielectrics that fail at a specific temperature due to the non-conjugated precursor polymer irreversibly switching from an insulator to the conjugated polymer, which serves as a bleed resistor. The precursor polymer is a good dielectric until it reaches a specific temperature determined by the stability of the leaving groups. Conjugation of the polymer backbone at high temperature effectively disables the capacitor, providing a `built-in` safety mechanism for electronic devices.

Dirk, Shawn M.; Johnson, Ross S.

2013-04-30T23:59:59.000Z

148

Multilayer dielectric diffraction gratings  

DOE Patents [OSTI]

The design and fabrication of dielectric grating structures with high diffraction efficiency used in reflection or transmission is described. By forming a multilayer structure of alternating index dielectric materials and placing a grating structure on top of the multilayer, a diffraction grating of adjustable efficiency, and variable optical bandwidth can be obtained. Diffraction efficiency into the first order in reflection varying between 1 and 98 percent has been achieved by controlling the design of the multilayer and the depth, shape, and material comprising the grooves of the grating structure. Methods for fabricating these gratings without the use of ion etching techniques are described.

Perry, Michael D. (Livermore, CA); Britten, Jerald A. (Oakley, CA); Nguyen, Hoang T. (Livermore, CA); Boyd, Robert (Livermore, CA); Shore, Bruce W. (Livermore, CA)

1999-01-01T23:59:59.000Z

149

Multilayer dielectric diffraction gratings  

DOE Patents [OSTI]

The design and fabrication of dielectric grating structures with high diffraction efficiency used in reflection or transmission is described. By forming a multilayer structure of alternating index dielectric materials and placing a grating structure on top of the multilayer, a diffraction grating of adjustable efficiency, and variable optical bandwidth can be obtained. Diffraction efficiency into the first order in reflection varying between 1 and 98 percent has been achieved by controlling the design of the multilayer and the depth, shape, and material comprising the grooves of the grating structure. Methods for fabricating these gratings without the use of ion etching techniques are described. 7 figs.

Perry, M.D.; Britten, J.A.; Nguyen, H.T.; Boyd, R.; Shore, B.W.

1999-05-25T23:59:59.000Z

150

Photonic laser-driven accelerator for GALAXIE  

SciTech Connect (OSTI)

We report on the design and development of an all-dielectric laser-driven accelerator to be used in the GALAXIE (GV-per-meter Acce Lerator And X-ray-source Integrated Experiment) project's compact free-electron laser. The approach of our working design is to construct eigenmodes, borrowing from the field of photonics, which yield the appropriate, highly demanding dynamics in a high-field, short wavelength accelerator. Topics discussed include transverse focusing, power coupling, bunching, and fabrication.

Naranjo, B.; Ho, M.; Hoang, P.; Putterman, S.; Valloni, A.; Rosenzweig, J. B. [UCLA Dept. of Physics and Astronomy Los Angeles, CA 90095-1547 (United States)

2012-12-21T23:59:59.000Z

151

The evolution of high energy accelerators  

SciTech Connect (OSTI)

Accelerators have been devised and built for two reasons: In the first place, by physicists who needed high energy particles in order to have a means to explore the interactions between particles that probe the fundamental elementary forces of nature. And conversely, sometimes accelerator builders produce new machines for higher energy than ever before just because it can be done, and then challenge potential users to make new discoveries with the new means at hand. These two approaches or motivations have gone hand in hand. This lecture traces how high energy particle accelerators have grown from tools used for esoteric small-scale experiments to the gigantic projects of today. So far all the really high-energy machines built and planned in the world--except the SLC--have been ring accelerators and storage rings using the strong-focusing method. But this method has not removed the energy limit, it has only pushed it higher. It would seem unlikely that one can go beyond the Large Hadron Collider (LHC)--but in fact a workshop was held in Sicily in November 1991, concerned with the question of extrapolating to 100 TeV. Other acceleration and beam-forming methods are now being discussed--collective fields, laser acceleration, wake-field accelerators etc., all aimed primarily at making linear colliders possible and more attractive than with present radiofrequency methods. So far it is not entirely clear which of these schemes will dominate particle physics in the future--maybe something that has not been thought of as yet.

Courant, E.D.

1994-08-01T23:59:59.000Z

152

Future Accelerators (?)  

E-Print Network [OSTI]

I describe the future accelerator facilities that are currently foreseen for electroweak scale physics, neutrino physics, and nuclear structure. I will explore the physics justification for these machines, and suggest how the case for future accelerators can be made.

John Womersley

2003-08-09T23:59:59.000Z

153

Linear Accelerator  

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

Linear Accelerator (LINAC) The core of the LANSCE facility is one of the nation's most powerful proton linear accelerators or LINAC. The LINAC at LANSCE has served the nation since...

154

Giant Dielectric Constant Controlled by Maxwell-Wagner Dielectric  

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

Giant Dielectric Constant Controlled Giant Dielectric Constant Controlled by Maxwell-Wagner Dielectric Relaxation in Al2O3/TiO2 Nanolaminates Synthesized by Atomic Layer Deposition Giant Dielectric Constant Controlled by Maxwell-Wagner Dielectric Relaxation in Al2O3/TiO2 Nanolaminates Synthesized by Atomic Layer Deposition Nanolaminate consisting of Al2O3 and TiO2 oxide sublayers were synthesized, using atomic layer deposition (ALD) to produce individual layers with atomic scale control. The main goal of this work is to produce robust high dielectric constant layers based on biocompatible materials, such as Al2O3 and TiO2, suitable to fabricate high-capacitance capacitors for microchip embedded energy storage capacitor for implantable biomedical devices. However, these capacitors based on Al2O3/TiO2 nanolaminates can provide

155

Additive manufacturing of graded dielectrics  

Science Journals Connector (OSTI)

A method for the fabrication of graded dielectrics within a structural composite is presented. This system employs an ultrasonic powder deposition head to print high dielectric powders onto a woven fabric composite substrate. It is shown how this system can integrate 3D variations of dielectric properties at millimeter resolution within a mechanically rugged substrate. To conclude, the system's practical application is demonstrated with experimental results from a graded index lens.

David A Roper; Brandon L Good; Raymond McCauley; Shridhar Yarlagadda; Jared Smith; Austin Good; Peter Pa; Mark S Mirotznik

2014-01-01T23:59:59.000Z

156

WF-NOTE-238  

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

6 6 March 21, 2011 Dielectric Wakefield Accelerator to Drive the Future FEL Light Source C. Jing 1,2 , J. Power 1 , and A. Zholents 3 1. High Energy Physics Division, ANL 2. Euclid Techlabs, LLC 3. Advanced Photon Source, ANL Abstract: 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

157

Acceleration Fund  

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

for these Venture Acceleration Fund awards, which have already produced a significant return on investment for the regional companies that have received them," said Padilla....

158

Dielectric Elastomers for Actuation and Energy Harvesting  

E-Print Network [OSTI]

1.23 Arm wrestling robot using dielectric elastomer springdemonstration of the arm wrestling robot. [265] Smart MaterMichael Wissler. An arm wrestling robot driven by dielectric

Brochu, Paul

2012-01-01T23:59:59.000Z

159

Meter scale plasma source for plasma wakefield experiments  

SciTech Connect (OSTI)

High accelerating gradients generated by a high density electron beam moving through plasma has been used to double the energy of the SLAC electron beam [1]. During that experiment, the electron current density was high enough to generate its own plasma without significant head erosion. In the newly commissioned FACET facility at SLAC, the peak current will be lower and without pre-ionization, head erosion will be a significant challenge for the planned experiments. In this work we report on our design of a meter scale plasma source for these experiments to effectively avoid the problem of head erosion. The plasma source is based on a homogeneous metal vapor gas column that is generated in a heat pipe oven [2]. A lithium oven over 30 cm long at densities over 10{sup 17} cm{sup -3} has been constructed and tested at UCLA. The plasma is then generated by coupling a 10 TW short pulse Ti:Sapphire laser into the gas column using an axicon lens setup. The Bessel profile of the axicon setup creates a region of high intensity that can stretch over the full length of the gas column with approximately constant diameter. In this region of high intensity, the alkali metal vapor is ionized through multi-photon ionization process. In this manner, a fully ionized meter scale plasma of uniform density can be formed. Methods for controlling the plasma diameter and length will also be discussed.

Vafaei-Najafabadi, N.; Shaw, J. L.; Marsh, K. A.; Joshi, C.; Hogan, M. J. [Department of Electrical Engineering, University of California Los Angeles, Los Angeles, CA 90095 (United States); SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States)

2012-12-21T23:59:59.000Z

160

E-Print Network 3.0 - accelerator system accelerator Sample Search...  

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

and Fusion Center, High-Energy-Density Physics Group Collection: Plasma Physics and Fusion ; Physics 80 Visual Exploration of Turbulent Combustion and Laser-Wakefield...

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

American Institute of Aeronautics and Astronautics Exploration of Ceramic Dielectrics for Microscale Dielectric  

E-Print Network [OSTI]

American Institute of Aeronautics and Astronautics 1 Exploration of Ceramic Dielectrics silicon dioxide for the dielectric barrier with thicknesses of 5 and 10 µm. Using a ceramic dielectric by a dielectric material, the dielectric barrier discharge, or DBD, is capable of generating a weakly ionized, non-thermal

Roy, Subrata

162

Accelerate Energy  

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

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

163

Accelerated Testing Validation  

E-Print Network [OSTI]

the University of California. Accelerated Testing Validationmaterials requires relevant Accelerated Stress Tests (ASTs),

Mukundan, Rangachary

2013-01-01T23:59:59.000Z

164

Nanoscale Heat Conduction across Metal-Dielectric Interfaces  

E-Print Network [OSTI]

resistance between a metal and a dielectric material assumedresistance of a metallic film bounded by dielectric materials.resistance of a metallic film bounded by dielectric materials.

Ju, Y. Sungtaek

2005-01-01T23:59:59.000Z

165

Application Acceleration  

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

Acceleration Acceleration on Current and Future Cray Platforms Alice Koniges, Robert Preissl, Jihan Kim, Lawrence Berkeley National Laboratory David Eder, Aaron Fisher, Nathan Masters, Velimir Mlaker, Lawrence Livermore National Laboratory Stephane Ethier, Weixing Wang, Princeton Plasma Physics Laboratory Martin Head-Gordon, University of California, Berkeley and Nathan Wichmann, Cray Inc. ABSTRACT: Application codes in a variety of areas are being updated for performance on the latest architectures. We describe current bottlenecks and performance improvement areas for applications including plasma physics, chemistry related to carbon capture and sequestration, and material science. We include a variety of methods including advanced hybrid parallelization using multi-threaded MPI, GPU acceleration, libraries and auto- parallelization compilers. KEYWORDS: hybrid

166

A microsecond-pulsewidth, intense, light-ion beam accelerator  

SciTech Connect (OSTI)

A relatively long-pulsewidth (0.1-1 {mu}s) intense ion beam accelerator has been built for materials processing applications. An applied-B{sub r}, magnetically-insulated extraction ion diode with dielectric flashover ion source is installed directly onto the output of a 1.2-MV, 300-kJ Marx generator. Initial operation of the accelerator at 0.4 MV indicates satisfactory performance without the need for additional pulse-shaping.

Rej, D.J.; Bartsch, R.R.; Davis, H.A.; Greenly, J.B.; Waganaar, W.J.

1993-07-01T23:59:59.000Z

167

Terahertz electromagnetic wave generation and amplification by an electron beam in the elliptical plasma waveguides with dielectric rod  

SciTech Connect (OSTI)

The propagation of electromagnetic waves in an elliptical plasma waveguide including strongly magnetized plasma column and a dielectric rod is investigated. The dispersion relation of guided hybrid electromagnetic waves is obtained. Excitation of the waves by a thin annular relativistic elliptical electron beam will be studied. The time growth rate of electromagnetic waves is obtained. The effects of relative permittivity constant of dielectric rod, radius of dielectric rod, accelerating voltage, and current density of the annular elliptical beam on the growth rate and the frequency spectra are numerically presented.

Rahmani, Z., E-mail: z.rahmani@kashanu.ac.ir; Jazi, B. [Department of Laser and Photonics, Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Heidari-Semiromi, E. [Department of Condense Matter, Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of)

2014-09-15T23:59:59.000Z

168

About Accelerators | Jefferson Lab  

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

Accelerator Brochure top-right bottom-left-corner bottom-right-corner About Accelerators Jefferson Lab is home to two superconducting radiofrequency accelerators: the...

169

GPU accelerated cardiac electrophysiology  

E-Print Network [OSTI]

OF THE THESIS GPU Accelerated Cardiac Electrophysiology bySAN DIEGO GPU Accelerated Cardiac Electrophysiology A thesistoolkit for developing GPU accelerated programs called CUDA,

Lionetti, Fred

2010-01-01T23:59:59.000Z

170

Electric and Magnetic Walls on Dielectric Interfaces  

E-Print Network [OSTI]

Sufficient conditions of the existence of electric or magnetic walls on dielectric interfaces are given for a multizone uniform dielectric waveguiding system. If one of two adjacent dielectric zones supports a TEM field distribution while the other supports a TM (TE) field distribution, then the common dielectric interface behaves as an electric (magnetic) wall, that is, the electric (magnetic) field line is perpendicular to the interface while the magnetic (electric) field line is parallel to the interface.

Changbiao Wang

2010-07-20T23:59:59.000Z

171

Fermilab | Illinois Accelerator Research Center | Accelerators...  

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

Accelerators and Society Physicists have been inventing new types of accelerators to propel charged particles to higher and higher energies for more than 80 years. Today, besides...

172

Effect of the laser wavefront in a laser-plasma accelerator  

E-Print Network [OSTI]

A high repetition rate electron source was generated by tightly focusing kHz, few-mJ laser pulses into an underdense plasma. This high intensity laser-plasma interaction led to stable electron beams over several hours but with strikingly complex transverse distributions even for good quality laser focal spots. Analysis of the experimental data, along with results of PIC simulations demonstrate the role of the laser wavefront on the acceleration of electrons. Distortions of the laser wavefront cause spatial inhomogeneities in the out-of-focus laser distribution and consequently, the laser pulse drives an inhomogenous transverse wakefield whose focusing/defocusing properties affect the electron distribution. These findings explain the experimental results and suggest the possibility of controlling the electron spatial distribution in laser-plasma accelerators by tailoring the laser wavefront.

Beaurepaire, B; Bocoum, M; Bhle, F; Jullien, A; Rousseau, J-P; Lefrou, T; Douillet, D; Iaquaniello, G; Lopez-Martens, R; Lifschitz, A; Faure, J

2015-01-01T23:59:59.000Z

173

Advances in laser driven accelerator R&D  

SciTech Connect (OSTI)

Current activities (last few years) at different laboratories, towards the development of a laser wakefield accelerator (LWFA) are reviewed, followed by a more in depth discussion of results obtained at the L'OASIS laboratory of LBNL. Recent results on laser guiding of relativistically intense beams in preformed plasma channels are discussed. The observation of mono-energetic beams in the 100 MeV energy range, produced by a channel guided LWFA at LBNL, is described and compared to results obtained in the unguided case at LOA, RAL and LBNL. Analysis, aided by particle-in-cell simulations, as well as experiments with various plasma lengths and densities, indicate that tailoring the length of the accelerator has a very beneficial impact on the electron energy distribution. Progress on laser triggered injection is reviewed. Results are presented on measurements of bunch duration and emittance of the accelerated electron beams, that indicate the possibility of generating femtosecond duration electron bunches. Future challenges and plans towards the development of a 1 GeV LWFA module are discussed.

Leemans, Wim

2004-08-23T23:59:59.000Z

174

Methods and apparatus for vertical coupling from dielectric waveguides  

SciTech Connect (OSTI)

A frequency-chirped nano-antenna provides efficient sub-wavelength vertical emission from a dielectric waveguide. In one example, this nano-antenna includes a set of plasmonic dipoles on the opposite side of a SiYV.sub.4 waveguide from a ground plane. The resulting structure, which is less than half a wavelength long, emits a broadband beam (e.g., >300 nm) that can be coupled into an optical fiber. In some embodiments, a diffractive optical element with unevenly shaped regions of high- and low-index dielectric material collimates the broadband beam for higher coupling efficiency. In some cases, a negative lens element between the nano-antenna and the diffractive optical element accelerates the emitted beam's divergence (and improves coupling efficiency), allowing for more compact packaging. Like the diffractive optical element, the negative lens element includes unevenly shaped regions of high- and low-index dielectric material that can be designed to compensate for aberrations in the beam emitted by the nano-antenna.

Yaacobi, Ami; Cordova, Brad Gilbert

2014-06-17T23:59:59.000Z

175

Chemical Accelerators The phrase "chemical accelerators"  

E-Print Network [OSTI]

Meetings Chemical Accelerators The phrase "chemical accelerators" is scarcely older than for one or two dozen people grew to include nearly a hundred. Chemical accelerators is a name sug- gested-volt region. Thus chemical accelerators can provide the same type of information for elemen- tary chemical

Zare, Richard N.

176

Argonne Today  

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

Argonne logo Argonne logo Argonne Today Wednesday, June 6, 2007 Seminars Submit seminar listings to seminars@anl.gov. There are no seminars scheduled today. Thursday, June 7 High Energy Physics Division Astrophysics Luncheon: "VERITAS - History, Status and First Results" by Deirdre Horan (HEP). Noon, Building 213 Cafeteria Private Dining Room A. Science update Wakefield facility achieves acceleration milestone Scientists at the Argonne Wakefield Accelerator facility are developing advanced technologies relevant to future high-energy physics machines. Their main goal is to identify and develop acceleration methods that may lead to more efficient, compact, and inexpensive particle accelerators. The method being pursued by the Argonne group is electron beam-driven wakefield acceleration in dielectric loaded structures, where a high-charge electron beam excites a high acceleration gradient.

177

Tailoring dielectric properties of ferroelectric-dielectric multilayers  

SciTech Connect (OSTI)

We develop a nonlinear thermodynamic model for multilayer ferroelectric heterostructures that takes into account electrostatic and electromechanical interactions between layers. We concentrate on the effect of relative layer fractions and in-plane thermal stresses on dielectric properties of Ba{sub 0.6}Sr{sub 0.4}TiO{sub 3}-, BaTiO{sub 3}-, and PbZr{sub 0.2}Ti{sub 0.8}O{sub 3} (PZT)-SrTiO{sub 3} (STO) multilayers on Si and c-sapphire. We show that dielectric properties of such multilayers can be significantly enhanced by tailoring the growth/processing temperature and the STO layer fraction. Our computations show that large tunabilities (?90% at 400?kV/cm) are possible in carefully designed barium strontium titanate-STO and PZT-STO even on Si for which there exist substantially large in-plane strains.

Kesim, M. T.; Zhang, J. [Department of Materials Science and Engineering and Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269 (United States); Cole, M. W. [U.S. Army Research Laboratory, Weapons and Materials Research Directorate, Aberdeen Proving Ground, Maryland 21005 (United States); Misirlioglu, I. B. [Faculty of Engineering and Natural Sciences, Sabanc? University, Orhanl?/Tuzla, 34956 Istanbul (Turkey); Alpay, S. P., E-mail: p.alpay@ims.uconn.edu [Department of Materials Science and Engineering and Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269 (United States); Department of Physics, University of Connecticut, Storrs, Connecticut 06269 (United States)

2014-01-13T23:59:59.000Z

178

Accelerating Solutions  

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

Solutions From vehicles on the road to the energy that powers them, Oak Ridge National Laboratory innovations are advancing American transportation. Oak Ridge National Laboratory is making an impact on everyday America by enhancing transportation choices and quality of life. Through strong collaborative partnerships with industry, ORNL research and development efforts are helping accelerate the deployment of a new generation of energy efficient vehicles powered by domestic, renewable, clean energy. EPA ultra-low sulfur diesel fuel rule ORNL and the National Renewable Energy Laboratory co-led a comprehensive research and test program to determine the effects of diesel fuel sulfur on emissions and emission control (catalyst) technology. In the course of this program, involving

179

Accelerating projects  

SciTech Connect (OSTI)

This chapter describes work at ORNL in the period around 1950, when the laboratory was evolving from its original mission of research aimed at producing the atomic bomb, to a new mission, which in many ways was unclear. The research division from Y-12 merged with the laboratory, which gave an increased work force, access to a wide array of equipment, and the opportunity to work on a number of projects related to nuclear propulsion. The first major project was for a nuclear aircraft. From work on this program, a good share of the laboratories work in peaceful application of nuclear energy would spring. A major concern was the development of light weight shielding to protect the crew and materials in such a plane. To do such shielding work, the laboratory employed existing, and new reactors. The original plans called for the transfer of reactor work to Argonne, but because of their own research load, and the needs of the lab, new reactor projects were started at the lab. They included the Low Intensity Test Reactor, the Swimming Pool Reactor, the Bulk Shielding Reactor, the Tower Shielding Facility, and others. The laboratory was able to extend early work on calutrons to accelerator development, pursuing both electrostatic accelerators and cyclotrons. The aircraft project also drove the need for immense quantities of scientific data, with rapid analysis, which resulted the development of divisions aimed at information support and calculational support. The laboratory also expanded its work in the effects of radiation and cells and biological systems, as well as in health physics.

Not Available

1992-01-01T23:59:59.000Z

180

Teleportation of Accelerated Information  

E-Print Network [OSTI]

A theoretical quantum teleportation protocal is suggested to teleport accelerated and non-accelerated information over different classes of accelerated quantum channels. For the accelerated information, it is shown that the fidelity of the teleported state increases as the entanglement of the initial quantum channel increases. However as the difference between the accelerated channel and the accelerated information decreases the fidelity increases. The fidelity of the non accelerated information increases as the entanglement of the initial quantum channel increases, while the accelerations of the quantum channel has a little effect. The possibility of sending quantum information over accelerated quantum channels is much better than sending classical information.

N. Metwally

2012-06-17T23:59:59.000Z

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Electromechanics of dielectric particles in dielectric liquids acted on by a microelectrode array  

E-Print Network [OSTI]

Arrays of microelectrodes were used to apply forces to dielectric (soda lime glass) spheres in a thin (200 micrometer thick) layer of a dielectric liquid polymer (EOPN 8021). The microelectrodes were fabricated using standard photolithographic...

Seo, Cheong Soo

2006-04-12T23:59:59.000Z

182

Time growth rate and field profiles of hybrid modes excited by a relativistic elliptical electron beam in an elliptical metallic waveguide with dielectric rod  

SciTech Connect (OSTI)

The dispersion relation of guided electromagnetic waves propagating in an elliptical metallic waveguide with a dielectric rod driven by relativistic elliptical electron beam (REEB) is investigated. The electric field profiles and the growth rates of the waves are numerically calculated by using Mathieu functions. The effects of relative permittivity constant of dielectric rod, accelerating voltage, and current density of REEB on the growth rate are presented.

Jazi, B.; Rahmani, Z.; Abdoli-Arani, A. [Faculty of Physics, Department of Laser and Photonics, University of Kashan, Kashan (Iran, Islamic Republic of); Heidari-Semiromi, E. [Faculty of Physics, Department of Condense Matter, University of Kashan, Kashan (Iran, Islamic Republic of)

2012-10-15T23:59:59.000Z

183

for sequence accelerators  

E-Print Network [OSTI]

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

Zakharov, Vladimir

184

COLLECTIVE PHENOMENA IN ACCELERATORS  

E-Print Network [OSTI]

Proc. 1971 Particle Accelerator Conference, IEEE Trans. onConference on High-Energy Accelerators) 1971 (CERN, Geneva,and P. R. Zenkevich, Particle Accelerators b 1 (1972). M. S.

Sessler, Andrew M.

2008-01-01T23:59:59.000Z

185

High-Current Accelerators  

E-Print Network [OSTI]

F i g . 13 F i g . 14 A 48 ACCELERATOR F i g . 25 F i g . 16supply. Extrapolation of accelerator energy and current9 . A-48 high-current accelerator, low-velocity end. Fig.

Lawrence, Ernest O.

1955-01-01T23:59:59.000Z

186

Graphene sustained nonlinear modes in dielectric waveguides  

Science Journals Connector (OSTI)

We discuss the existence of nonlinear modes sustained by graphene layers in dielectric waveguides. Taking advantage of the almost two dimensional nature of graphene, we introduce the...

Auditore, Aldo; De Angelis, Costantino; Locatelli, Andrea; Boscolo, Stefano; Midrio, Michele; Romagnoli, Marco; Capobianco, Antonio-Daniele; Nalesso, Gianfranco

2013-01-01T23:59:59.000Z

187

PNL-SA-22914 Presented at the 48th Meeting of the Mechanical Failures Prevention Group (MFPG 48) 19-21 April 1994 in Wakefield, MA  

E-Print Network [OSTI]

-21 April 1994 in Wakefield, MA AN ARTIFICIAL NEURAL NETWORK SYSTEM FOR DIAGNOSING GAS TURBINE ENGINE FUEL Laboratory are developing a turbine engine diagnostic system for the M1A1 Abrams tank. This system employs Artificial Neural Network (ANN) technology to perform diagnosis and prognosis of the tank's AGT-1500 gas

188

Argonne Accelerator Institute  

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

AAI Home AAI Home Welcome Accelerators at Argonne Mission Organization History Document Collection Conferences & Workshops Beams and Applications Seminar Argonne-Fermilab Collaboration Lee Teng Scholarship Program Useful Links Argonne Accelerator Institute In 2006, Argonne Laboratory Director Robert Rosner formed the AAI as a focal point for accelerator initiatives. The institute works to utilize Argonne's extensive accelerator resources, to enhance existing facilities, to determine the future of accelerator development and construction, and to oversee a dynamic and acclaimed accelerator physics portfolio. More Information for: Members * Students Industrial Collaborators - Working with Argonne Link to: Accelerators for America's Future Upcoming Events and News 4th International Particle Accelerator Conference (IPAC'13)

189

Fermilab | Science | Particle Accelerators  

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

Particle Accelerators Main Injector As America's particle physics laboratory, Fermilab operates and builds powerful particle accelerators for investigating the smallest things...

190

Focusing in Linear Accelerators  

DOE R&D Accomplishments [OSTI]

Review of the theory of focusing in linear accelerators with comments on the incompatibility of phase stability and first-order focusing in a simple accelerator.

McMillan, E. M.

1950-08-24T23:59:59.000Z

191

Lab announces Venture Acceleration  

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

Inc., and ThermaSun Inc. as recipients of awards from the Los Alamos National Security, LLC Venture Acceleration Fund. The Laboratory's Venture Acceleration Fund provides...

192

Mechanical constraints enhance electrical energy densities of soft dielectrics  

E-Print Network [OSTI]

Mechanical constraints enhance electrical energy densities of soft dielectrics Lin Zhang, Qiming, the dielectric will breakdown electrically. The breakdown limits the electrical energy density of the dielectric electric fields and thus increase their electrical energy densities. The mechanical constraints suppress

Ferrari, Silvia

193

Dielectric liquid ionization chambers for detecting fast neutrons  

E-Print Network [OSTI]

Three ionization chambers with different geometries have been constructed and filled with dielectric liquids for detection of fast neutrons. The three dielectric liquids studied were Tetramethylsilane (TMS), Tetramethylpentane ...

Boyd, Erin M

2008-01-01T23:59:59.000Z

194

Integrated Circuit / Microfluidic Chips for Dielectric Manipulation  

E-Print Network [OSTI]

Integrated Circuit / Microfluidic Chips for Dielectric Manipulation A THESIS PRESENTED BY THOMAS by Thomas Hunt All rights reserved. #12;iii Abstract Integrated Circuit / Microfluidic Chips for Dielectric of integrated circuit / microfluidic chips to move individual living cells and chemical droplets along

Heller, Eric

195

I. ACCELERATION A. Introduction  

E-Print Network [OSTI]

I. ACCELERATION A. Introduction Following cooling and initial bunch compression, the beams must be rapidly accelerated. The acceleration needed for a Higgs collider is probably the most conventional part undertaken. A sequence of linacs would work, but would be expensive. Some form of circulating acceleration

McDonald, Kirk

196

Superconducting Radiofrequency (SRF) Accelerator Cavities  

SciTech Connect (OSTI)

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

Reece, Charlie

2013-05-03T23:59:59.000Z

197

Superconducting Radiofrequency (SRF) Accelerator Cavities  

ScienceCinema (OSTI)

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

Reece, Charlie

2014-05-22T23:59:59.000Z

198

Method of and apparatus for accelerating a projectile  

DOE Patents [OSTI]

A projectile is accelerated along a confined path by supplying a pulsed high pressure, high velocity plasma jet to the rear of the projectile as the projectile traverses the path. The jet enters the confined path at a non-zero angle relative to the projectile path. The pulse is derived from a dielectric capillary tube having an interior wall from which plasma forming material is ablated in response to a discharge voltage. The projectile can be accelerated in response to the kinetic energy in the plasma jet or in response to a pressure increase of gases in the confined path resulting from the heat added to the gases by the plasma.

Goldstein, Yeshayahu S. A. (Gaithersburg, MD); Tidman, Derek A. (Silver Spring, MD)

1986-01-01T23:59:59.000Z

199

Laser wakefield simulation using a speed-of-light frame envelope model  

E-Print Network [OSTI]

Laser wake?eld simulation using a speed-of-light frameAbstract. Simulation of laser wake?eld accelerator (LWFA)extend hundreds of laser wave- lengths transversely and many

Cowan, B.

2010-01-01T23:59:59.000Z

200

A Beam Driven Plasma-Wakefield Linear Collider: From Higgs Factory...  

Office of Scientific and Technical Information (OSTI)

experiments that showed the great potential of plasma accelerators. The FACET ii test facility at SLAC will, in the period 2012-2016, further study several issues that are...

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Dielectric  

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

It is demonstrated that these corrections are important for evaluation of the plasma heating rate near ion cyclotron resonance in RFPs while they can be neglected in tokamak...

202

Fermilab | Illinois Accelerator Research Center | Illinois Accelerator  

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

photo: IARC photo: IARC As envisioned, the Illinois Accelerator Research Center will provide approximately 83,000 square feet of technical, office and classroom space for scientists and industrial partners. The Illinois Accelerator Research Center (IARC) is a new accelerator research facility being built at Fermi National Accelerator Laboratory. At the Illinois Accelerator Research Center, scientists and engineers from Fermilab, Argonne and Illinois universities will work side by side with industrial partners to research and develop breakthroughs in accelerator science and translate them into applications for the nation's health, wealth and security. Located on the Fermilab campus this 83,000 square foot, state-of-the-art facility will house offices, technical and educational space to study

203

Facility for Advanced Accelerator Experimental Tests at SLAC (FACET) Conceptual Design Report  

SciTech Connect (OSTI)

This Conceptual Design Report (CDR) describes the design of FACET. It will be updated to stay current with the developing design of the facility. This CDR begins as the baseline conceptual design and will evolve into an 'as-built' manual for the completed facility. The Executive Summary, Chapter 1, gives an introduction to the FACET project and describes the salient features of its design. Chapter 2 gives an overview of FACET. It describes the general parameters of the machine and the basic approaches to implementation. The FACET project does not include the implementation of specific scientific experiments either for plasma wake-field acceleration for other applications. Nonetheless, enough work has been done to define potential experiments to assure that the facility can meet the requirements of the experimental community. Chapter 3, Scientific Case, describes the planned plasma wakefield and other experiments. Chapter 4, Technical Description of FACET, describes the parameters and design of all technical systems of FACET. FACET uses the first two thirds of the existing SLAC linac to accelerate the beam to about 20GeV, and compress it with the aid of two chicanes, located in Sector 10 and Sector 20. The Sector 20 area will include a focusing system, the generic experimental area and the beam dump. Chapter 5, Management of Scientific Program, describes the management of the scientific program at FACET. Chapter 6, Environment, Safety and Health and Quality Assurance, describes the existing programs at SLAC and their application to the FACET project. It includes a preliminary analysis of safety hazards and the planned mitigation. Chapter 7, Work Breakdown Structure, describes the structure used for developing the cost estimates, which will also be used to manage the project. The chapter defines the scope of work of each element down to level 3.

Amann, J.; Bane, K.; /SLAC

2009-10-30T23:59:59.000Z

204

Controlled Electron Injection into Plasma Accelerators and SpaceCharge Estimates  

SciTech Connect (OSTI)

Plasma based accelerators are capable of producing electron sources which are ultra-compact (a few microns) and high energies (up to hundreds of MeVs) in much shorter distances than conventional accelerators. This is due to the large longitudinal electric field that can be excited without the limitation of breakdown as in RF structures.The characteristic scale length of the accelerating field is the plasma wavelength and for typical densities ranging from 1018 - 1019 cm-3, the accelerating fields and scale length can hence be on the order of 10-100GV/m and 10-40 mu m, respectively. The production of quasimonoenergetic beams was recently obtained in a regime relying on self-trapping of background plasma electrons, using a single laser pulse for wakefield generation. In this dissertation, we study the controlled injection via the beating of two lasers (the pump laser pulse creating the plasma wave and a second beam being propagated in opposite direction) which induce a localized injection of background plasma electrons. The aim of this dissertation is to describe in detail the physics of optical injection using two lasers, the characteristics of the electron beams produced (the micrometer scale plasma wavelength can result in femtosecond and even attosecond bunches) as well as a concise estimate of the effects of space charge on the dynamics of an ultra-dense electron bunch with a large energy spread.

Fubiani, Gwenael J.

2005-09-01T23:59:59.000Z

205

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

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

It produces the world's most powerful, high-energy neutrino beam and provides proton beams for various experiments and R&D programs. Fermilab's accelerator complex delivers...

206

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

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

Fermilab scientists and engineers develop particle accelerators to produce beams to take particle physics to the next level, collaborating with scientists and...

207

Layered Binary-Dielectrics for Energy Applications: Limitations and Potentials  

SciTech Connect (OSTI)

In this Letter, an attempt is made to illustrate how performance of an electrically insulating material, a dielectric, can be improved by constructing a layered binary-dielectric structure that employs a weak insulator with high dielectric permittivity. It is shown that layered binary-dielectrics could have a signicant impact on energy storage and electrical insulation.

Tuncer, Enis [ORNL

2012-01-01T23:59:59.000Z

208

Argonne Accelerator Institute  

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

Research and Development Research and Development Click to download a PDF version of this document. PDF Focus Research Areas Fundamental Accelerator Physics: Theory Importance Accelerator physics research is normally associated with specific accelerator projects. As a scientific discipline, however, it is useful to study fundamental accelerator phenomena decoupled, as much as possible, from specific project 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 the limitations and suggesting ways to overcome those limitations. Such basic research tends to be discouraged in a project-driven environment. For sustained and significant progress in

209

Epoxy Foam Encapsulants: Processing and Dielectric Characterization  

SciTech Connect (OSTI)

The dielectric performance of epoxy foams was investigated to determine if such materials might provide advantages over more standard polyurethane foams in the encapsulation of electronic assemblies. Comparisons of the dielectric characteristics of epoxy and urethane encapsulant foams found no significant differences between the two resin types and no significant difference between as-molded and machined foams. This study specifically evaluated the formulation and processing of epoxy foams using simple methylhydrosiloxanes as the flowing agent and compared the dielectric performance of those to urethane foams of similar density.

Linda Domeier; Marion Hunter

1999-01-01T23:59:59.000Z

210

RHIC | Accelerator Complex  

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

RHIC Accelerators RHIC Accelerators The Relativistic Heavy Ion Collider complex is actually composed of a long "chain" of particle accelerators Heavy ions begin their travels in the Electron Beam Ion Source accelerator (1). The ions then travel to the small, circular Booster (3) where, with each pass, they are accelerated to higher energy. From the Booster, ions travel to the Alternating Gradient Synchrotron (4), which then injects the beams via a beamline (5) into the two rings of RHIC (6). In RHIC, the beams get a final accelerator "kick up" in energy from radio waves. Once accelerated, the ions can "orbit" inside the rings for hours. RHIC can also conduct colliding-beam experiments with polarized protons. These are first accelerated in the Linac (2), and further in the Booster (3), AGS (4), and

211

Fermilab | Tevatron | Accelerator  

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

particle accelerator in the world before it shut down on Sept. 29, 2011. It accelerated beams of protons and antiprotons to 99.999954 percent of the speed of light around a...

212

History of Proton Linear Accelerators  

E-Print Network [OSTI]

much. References 1. Linear Accelerators, edited by P. M .at the 1986 Linear Accelerator Conference, SLAC, Stanford,HISTORY OF PROTON LINEAR ACCELERATORS Luis W. Alvarez TWO-

Alvarez, Luis W.

1987-01-01T23:59:59.000Z

213

LARGE-APERTURE D- ACCELERATORS  

E-Print Network [OSTI]

Vignetted current profile at accelerator entrance aperture 'LARGE-APERTURE D" ACCELERATORS* 0. A. Anderson" " Lawrencen i a 9-1720 Abstract Accelerator designs are described for

Anderson, O.A.

2010-01-01T23:59:59.000Z

214

Beam Dynamics for Induction Accelerators  

E-Print Network [OSTI]

Dynamics for Induction Accelerators Edward P. Lee Lawrencea natural candidate accelerator for a heavy ion fusion (HIF)words: Fusion, Induction, Accelerators, Dynamics This work

Lee, E.P.

2014-01-01T23:59:59.000Z

215

Investigation of dielectric overlay microstrip circuits  

E-Print Network [OSTI]

INVESTIGATION OF DIELECTRIC OVERLAY MICROSTRIP CIRCUITS A Thesis by JAMES LOUIS KLEIN Submitted to the Graduate College of Texas ARM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE August 1988 Major... Subject: Electrical Engineering INVESTIGATION OF DIELECTRIC OVERLAY MICRO STRIP CIRCUITS A Thesis by JAMES LOUIS KLEIN Approved as to style and content by: Kai Chang Robert D. Nevels (Member) Krzysztof A. Michalski (Member) Mark H. Weichold...

Klein, James Louis

1988-01-01T23:59:59.000Z

216

Method of casting patterned dielectric structures  

DOE Patents [OSTI]

A pattern of dielectric structures are formed directly on a substrate in a single step using sol-gel chemistry and molding procedures. The resulting dielectric structures are useful in vacuum applications for electronic devices. Porous, lightweight structures having a high aspect ratio that are suitable for use as spacers between the faceplate and baseplate of a field emission display can be manufactured using this method.

Poco, John F. (Livermore, CA); Hrubesh, Lawrence W. (Livermore, CA)

2001-01-01T23:59:59.000Z

217

Shielding of proton accelerators  

Science Journals Connector (OSTI)

......capabilities of an accelerator control system...meant to undergo a nuclear interaction within...the axis of the vacuum chamber. The beam...of high-energy accelerators. Nucl. Instrum...Series, Group I: Nuclear and Particle Physics-Schopper...100-250 MeV proton accelerators: double differential......

Stefano Agosteo; Matteo Magistris; Marco Silari

2011-07-01T23:59:59.000Z

218

ULTRA?COMPACT ACCELERATOR TECHNOLOGIES FOR APPLICATION IN NUCLEAR TECHNIQUES  

Science Journals Connector (OSTI)

We report on compact accelerator technology development for potential use as a pulsed neutron source quantitative post verifier. The technology is derived from our on?going compact accelerator technology development program for radiography under the US Department of Energy and for a clinic sized compact proton therapy systems under an industry sponsored Cooperative Research and Development Agreement. The accelerator technique relies on the synchronous discharge of a prompt pulse generating stacked transmission line structure with the beam transit. The goal of this technology is to achieve ?10 MV/m gradients for 10 s of nanoseconds pulses and ?100 MV/m gradients for ?1 ns systems. As a post verifier for supplementing existing x?ray equipment this system can remain in a charged stand?by state with little or no energy consumption. We describe the progress of our overall component development effort with the multilayer dielectric wall insulators (i.e. the accelerator wall) compact power supply technology kHz repetition?rate surface flashover ion sources and the prompt pulse generation system consisting of wide?bandgap switches and high performance dielectric materials.

S. Sampayan; G. Caporaso; Y.?J. Chen; V. Carazo; S. Falabella; G. Guethlein; S. Guse; J. R. Harris; S. Hawkins; C. Holmes; M. Krogh; S. Nelson; A. C. Paul; D. Pearson; B. Poole; R. Schmidt; D. Sanders; K. Selenes; S. Sitaraman; J. Sullivan; L. Wang; J. Watson

2009-01-01T23:59:59.000Z

219

Application of Plasma Waveguides to High Energy Accelerators  

SciTech Connect (OSTI)

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.

Milchberg, Howard M

2013-03-30T23:59:59.000Z

220

Argonne Accelerator Institute  

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

AAI Homepage Lee Teng Scholarship Program USPAS Argonne Department of Education Fermilab Education Office For Students Many scientific advances are made using accelerators. The world of High Energy Particle Physics has driven this field and continues to depend largely on accelerators. Increasingly advances in materials science, chemistry, biology and environmental science are being made at accelerators using x-ray and neutrons to probe matter. Accelerators have a number of commercial applications including isotope production for use in medicine, cancer treatment, processing semiconductor chips, and so on. Presently there are around 15,000 accelerators worldwide. Approximately 97% of these are used for commercial applications. However several hundred are in use

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Quasi-monoenergetic Electron Beams from Laser-plasma Acceleration by Ionization-induced Injection in Low- density Pure Nitrogen  

E-Print Network [OSTI]

We report a laser wakefield acceleration of electron beams up to 130 MeV from laser-driven 4-mm long nitrogen gas jet. By using a moderate laser intensity (3.5*10^18 W.cm^(-2) ) and relatively low plasma densities (0.8*10^18 cm^(-3) to 2.7*10^18 cm^(-3)) we have achieved a stable regime for laser propagation and consequently a stable generation of electron beams. We experimentally studied the dependence of the drive laser energy on the laser-plasma channel and electron beam parameters. The quality of the generated electron beams is discussed within the framework of the ionization-induced injection mechanism.

Tao, Mengze; Li, Song; Mirzaie, Mohammad; Chen, Liming; He, Fei; Cheng, Ya; Zhang, Jie

2014-01-01T23:59:59.000Z

222

The Contact Electricity of Solid Dielectrics  

Science Journals Connector (OSTI)

The electric charges produced by wringing optically flat surfaces together were measured in order to determine whether or not there is a possibility of formulating a single contact theory which will include both the metals and the dielectrics. Experiments with flint glass and steel proved that the frictional charge is independent of the amount of friction, provided only that intimate contact be established, and is proportional to the area of contact. The voltaic nature of the frictional charge. The charge was in no wise affected by the ionization of the residual air molecules between the surfaces by means of an intense beam of x-rays, and was also found to be independent of the duration of contact for periods varying up to 17 hours. The failure of the double-layer to recombine under these conditions proves that it was sustained by a voltaic field. The dependence of the effect on the dielectric constant. The charge per cm2 Q12 of material 1 in contact with material 2, was found for 8 different pairs of the materials, quartz, fluorite, crown glass, flint glass and steel, to satisfy, within 14 per cent, the equation Q12=C(K1-K2), where K1 and K2 are the dielectric constants and C is a positive constant, whose mean value is 4.43 e.s.u., provided the value K=3.1 be assigned to steel. This equation is consistent with the results of Coehn's measurements of electric osmosis.The electric effect of compressing amorphous dielectrics was determined by pressing two kinds of sheet rubber, of dielectric constants 2.94 and 3.96, against seven hard materials, whose dielectric constants ranged from 2.8 to 7.8. The charge on the compressible dielectric was found to be independent of the nature of the material against which it was pressed, proving that this is not a voltaic effect and that amorphous as well as crystalline substances can be electrified by pressure.The electric effect of collision of a solid insulator and a metal was found, with four pairs of materials, to be consistently opposite in sign to the frictional effect. This result shows that collision must be considered to produce two different effects, one of which is the voltaic charge, while the other is a transfer of electrons from the metal to the dielectric, due in all probability to the inertia of the mobile electrons.Dielectric constant of steel, as suggested by these results, is not infinity but 3.1.

Harold F. Richards

1923-08-01T23:59:59.000Z

223

Argonne Accelerator Institute  

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

Mission Mission The mission of the Argonne Accelerator Institute is centered upon the following related goals: Locate next generation accelerator facilities in Northern Illinois Advance accelerator technology Oversee a selected, strategic, lab-wide, and acclaimed accelerator R&D portfolio In order to accomplish the above goals, the institute has established five objectives. These are coupled to programmatic objectives, and are dependent on each other, but they serve to identify important areas for the institute to focus its activities. Educate the "next generation" of accelerator physicists and engineers Work with area Universities to establish Joint Appointments and Adjunct Professorships Identify students Provide research opportunities at Argonne Work with the US Particle Accelerator School

224

BNL | Accelerator Test Facility  

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

Accelerator Test Facility Accelerator Test Facility Home Core Capabilities Photoinjector S-Band Linac Laser Systems CO2 Laser Nd:Yag Laser Beamlines Beamline Simulation Data Beamline Parameters Beam Diagnostics Detectors Beam Schedule Operations Resources Fact Sheet (.pdf) Image Library Upgrade Proposal (.pdf) Publications ES&H Experiment Start-up ATF Handbook Laser Safety Collider-Accelerator Dept. C-AD ES&H Resources Staff Users' Place Apply for Access ATF photo ATF photo ATF photo ATF photo ATF photo A user facility for advanced accelerator research The Brookhaven Accelerator Test Facility (ATF) is a proposal driven, steering committee reviewed facility that provides users with high-brightness electron- and laser-beams. The ATF pioneered the concept of a user facility for studying complex properties of modern accelerators and

225

Argonne Accelerator Institute  

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

Welcome Welcome In 2006, Argonne laboratory director Robert Rosner formed the AAI as a focal point for accelerator initiatives. The institute works to utilize Argonne's extensive accelerator resources, to enhance existing facilities, to determine the future of accelerator development and construction, and to oversee a dynamic and acclaimed accelerator physics portfolio. I invite you to look around the content of this web site. Accelerators at Argonne describes our rich heritage in this field, particularly with respect to the development and support of user facilities. Initiatives describes the things we are hoping to do, and Research & Development discusses our research portfolio. If you are a graduate or undergraduate student wishing to pursue a career in accelerator science or technology, please see Educational

226

North Linear Accelerator  

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

North Linear Accelerator North Linear Accelerator Building Exterior Beam Enclosure Level Walk to the North Spreader North Recombiner Extras! North Linear Accelerator The North Linear Accelerator is one of the two long, straight sections of Jefferson Lab's accelerator. Electrons gain energy in this section by passing through acceleration cavities. There are 160 cavities in this straightaway, all lined up end to end. That's enough cavities to increase an electron's energy by 400 million volts each time it passes through this section. Electrons can pass though this section as many as five times! The cavities are powered by microwaves that travel down the skinny rectangular pipes from the service buildings above ground. Since the cavities won't work right unless they are kept very cold, they

227

Argonne Accelerator Institute  

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

The Argonne Accelerator History Document Collection The Argonne Accelerator History Document Collection The Argonne Accelerator Institute (AAI) has established a special collection of archived documents which describe notable Argonne accelerator work of the past 50 years. A list of such Argonne Accelerator Projects is given below. Each project is described briefly, with links to archived documents in this collection. This collection includes important Argonne accelerator documents which may have become difficult to locate, as well as ones which have broad scope. In keeping with its historical purpose, this collection only covers work done 10 or more years ago. Many of the listed documents are available online. We hope to make more of them available online in the future. [For several of the projects, interesting additional online documents can be found by

228

accelerators for ATI  

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

Building Accelerator Analogs Building Accelerator Analogs Some QuarkNet centers have built "accelerators." No, they are not real but can be used as analogs to real particle accelerators. The real learning comes, of course, when you plan and experiment on your own, but this may give you some starting points. Things to Think About What are your objectives? To make an analogy for particle accelerators? To use classical physics qualitatively? To use classical physics quantitatively? To measure forces, speed, etc.? _______________ Who is your target audience— in an Associate Teacher Institute or their students or both? What do the participants need to know before beginning? Jawbreaker Accelerator Pressurized gas shoots jawbreakers through PVC pipe into a fixed target (brick) or into each other. The original speeds and masses are measured as are those of the resulting particles.

229

Uniformly accelerated black holes  

Science Journals Connector (OSTI)

The static and stationary C metric are examined in a generic framework and their interpretations studied in some detail, especially those with two event horizons, one for the black hole and another for the acceleration. We find that (i) the spacetime of an accelerated static black hole is plagued by either conical singularities or a lack of smoothness and compactness of the black hole horizon, (ii) by using standard black hole thermodynamics we show that accelerated black holes have a higher Hawking temperature than Unruh temperature of the accelerated frame, and (iii) the usual upper bound on the product of the mass and acceleration parameters (<1/27) is just a coordinate artifact. The main results are extended to accelerated rotating black holes with no significant changes.

Patricio S. Letelier and Samuel R. Oliveira

2001-08-24T23:59:59.000Z

230

Method of fabricating a solar cell with a tunnel dielectric layer  

DOE Patents [OSTI]

Methods of fabricating solar cells with tunnel dielectric layers are described. Solar cells with tunnel dielectric layers are also described.

Dennis, Tim; Harrington, Scott; Manning, Jane; Smith, David; Waldhauer, Ann

2012-12-18T23:59:59.000Z

231

Method of fabricating a solar cell with a tunnel dielectric layer  

DOE Patents [OSTI]

Methods of fabricating solar cells with tunnel dielectric layers are described. Solar cells with tunnel dielectric layers are also described.

Dennis, Tim; Harrington, Scott; Manning, Jane; Smith, David D; Waldhauer, Ann

2014-04-29T23:59:59.000Z

232

Miniaturization Techniques for Accelerators  

SciTech Connect (OSTI)

The possibility of laser driven accelerators [1] suggests the need for new structures based on micromachining and integrated circuit technology because of the comparable scales. Thus, we are exploring fully integrated structures including sources, optics (for both light and particle) and acceleration in a common format--an accelerator-on-chip (AOC). Tests suggest a number of preferred materials and techniques but no technical or fundamental roadblocks at scales of order 1 {micro}m or larger.

Spencer, James E.

2003-05-27T23:59:59.000Z

233

Optically pulsed electron accelerator  

DOE Patents [OSTI]

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.

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

1985-05-20T23:59:59.000Z

234

Optically pulsed electron accelerator  

DOE Patents [OSTI]

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.

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

1987-01-01T23:59:59.000Z

235

Accelerated Testing Validation  

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

Accelerated Testing Validation Rangachary Mukundan (PI), Rodney Borup, John Davey, Roger Lujan Los Alamos National Laboratory Adam Z. Weber Lawrence Berkeley National Laboratory...

236

Market Acceleration (Fact Sheet)  

SciTech Connect (OSTI)

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

Not Available

2010-09-01T23:59:59.000Z

237

Accelerated Molecular Dynamics Methods  

Broader source: Energy.gov [DOE]

This presentation on Accelerated Molecular Dynamics Methods was given at the DOE Theory Focus Session on Hydrogen Storage Materials on May 18, 2006.

238

Accelerator Test Facility  

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

Director ATF, Accelerator External program committee W. Leemans, Chair M. Woodle Engineer Mechanical M. Montemagno Engineer Electrical I. Pogorelsky, Physicist, Laser P. Jacob...

239

Dielectric Constant and Transport Mechanism of Percolated Polyaniline Nanoclay Composites.  

Science Journals Connector (OSTI)

Dielectric Constant and Transport Mechanism of Percolated Polyaniline Nanoclay Composites. ... We report the dielectric constant and transport mechanism of intercalated nanoclaypolyaniline composite, an industrially ready to use novel nanocomposite, which is prepared by a simple mechanochemical method. ...

Mini Vellakkat; Archana Kamath; S. Raghu; Sharanappa Chapi; Devendrappa Hundekal

2014-09-30T23:59:59.000Z

240

Method for fabrication of crack-free ceramic dielectric films  

DOE Patents [OSTI]

The invention provides a process for forming crack-free dielectric films on a substrate. The process comprise the application of a dielectric precursor layer of a thickness from about 0.3 .mu.m to about 1.0 .mu.m to a substrate. The deposition is followed by low temperature heat pretreatment, prepyrolysis, pyrolysis and crystallization step for each layer. The deposition, heat pretreatment, prepyrolysis, pyrolysis and crystallization are repeated until the dielectric film forms an overall thickness of from about 1.5 .mu.m to about 20.0 .mu.m and providing a final crystallization treatment to form a thick dielectric film. Also provided was a thick crack-free dielectric film on a substrate, the dielectric forming a dense thick crack-free dielectric having an overall dielectric thickness of from about 1.5 .mu.m to about 20.0 .mu.m.

Ma, Beihai; Balachandran, Uthamalingam; Chao, Sheng; Liu, Shanshan; Narayanan, Manoj

2014-02-11T23:59:59.000Z

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Studies on metal-dielectric plasmonic structures.  

SciTech Connect (OSTI)

The interaction of light with nanostructured metal leads to a number of fascinating phenomena, including plasmon oscillations that can be harnessed for a variety of cutting-edge applications. Plasmon oscillation modes are the collective oscillation of free electrons in metals under incident light. Previously, surface plasmon modes have been used for communication, sensing, nonlinear optics and novel physics studies. In this report, we describe the scientific research completed on metal-dielectric plasmonic films accomplished during a multi-year Purdue Excellence in Science and Engineering Graduate Fellowship sponsored by Sandia National Laboratories. A variety of plasmonic structures, from random 2D metal-dielectric films to 3D composite metal-dielectric films, have been studied in this research for applications such as surface-enhanced Raman sensing, tunable superlenses with resolutions beyond the diffraction limit, enhanced molecular absorption, infrared obscurants, and other real-world applications.

Chettiar, Uday K. (Purdue University, West Lafayette, IN); Liu, Zhengtong (Purdue University, West Lafayette, IN); Thoreson, Mark D. (Purdue University, West Lafayette, IN); Shalaev, Vladimir M. (Purdue University, West Lafayette, IN); Drachev, Vladimir P. (Purdue University, West Lafayette, IN); Pack, Michael Vern; Kildishev, Alexander V. (Purdue University, West Lafayette, IN); Nyga, Piotr (Purdue University, West Lafayette, IN)

2010-01-01T23:59:59.000Z

242

Tuneable dielectric films having low electrical losses  

DOE Patents [OSTI]

The present invention is directed to a method for forming dielectric thin films having substantially reduced electrical losses at microwave and millimeter wave frequencies relative to conventional dielectric thin films. The reduction in losses is realized by dramatically increasing the grain sizes of the dielectric films, thereby minimizing intergranular scattering of the microwave signal due to grain boundaries and point defects. The increase in grain size is realized by heating the film to a temperature at which the grains experience regrowth. The grain size of the films can be further increased by first depositing the films with an excess of one of the compoents, such that a highly mobile grain boundary phase is formed.

Dimos, Duane Brian (Albuquerque, NM); Schwartz, Robert William (Albuquerque, NM); Raymond, Mark Victor (Albuquerque, NM); Al-Shareef, Husam Niman (Boise, ID); Mueller, Carl (Lakewood, CO); Galt, David (Denver, CO)

2000-01-01T23:59:59.000Z

243

DOE Designated Facilities  

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

Research Argonne Wakefield Accelerator (AWA) Argonne Tandem Linac Accelerator System (ATLAS) Center for Nanoscale Materials Leadership Computing Facility* Brookhaven National...

244

Polyamide 66 as a Cryogenic Dielectric  

SciTech Connect (OSTI)

Improvements in superconductor and cryogenic technologies enable novel power apparatus, \\eg, cables, transformers, fault current limiters, generators, \\etc, with better device characteristics than their conventional counterparts. In these applications electrical insulation materials play an important role in system weight, footprint (size), and voltage level. The trend in the electrical insulation material selection has been to adapt or to employ conventional insulation materials to these new systems. However, at low temperatures, thermal contraction and loss of mechanical strength in many materials make them unsuitable for superconducting power applications. In this paper, a widely used commercial material was characterized as a potential cryogenic dielectric. The material is used in ``oven bag'' a heat-resistant polyamide (nylon) used in cooking (produced by Reynolds\\textregistered, Richmond, VA, USA). It is first characterized by Fourier transform infrared and x-ray diffraction techniques and determined to be composed of polyamide 66 (PA66) polymer. Secondly the complex dielectric permittivity and dielectric breakdown strength of the PA66 films are investigated. The dielectric data are then compared with data reported in the literature. A comparison of dielectric strength with a widely used high-temperature superconductor electrical insulation material, polypropylene-laminated paper (PPLP\\texttrademark\\ a product of Sumitomo Electric Industries, Japan), is provided. It is observed that the statistical analysis of the PA66 films yields 1\\% failure probability at $127\\ \\kilo\\volt\\milli\\meter^{-1}$; this value is approximately $46\\ \\kilo\\volt\\milli\\meter^{-1}$ higher than PPLP\\texttrademark. It is concluded that PA66 may be a good candidate for cryogenic applications. Finally, a summary of dielectric properties of some of the commercial tape insulation materials and various polymers is also provided.

Tuncer, Enis [ORNL; Polyzos, Georgios [ORNL; Sauers, Isidor [ORNL; James, David Randy [ORNL; Ellis, Alvin R [ORNL; Messman, Jamie M [ORNL; Aytug, Tolga [ORNL

2009-01-01T23:59:59.000Z

245

Method for producing high dielectric strength microvalves  

DOE Patents [OSTI]

A microvalve having a cast-in-place and lithographically shaped mobile, polymer monolith for fluid flow control in microfluidic devices and method of manufacture. The microvalve contains a porous fluorinated polymer monolithic element whose pores are filled with an electrically insulating, high dielectric strength fluid, typically a perfluorinated liquid. This combination provides a microvalve that combines high dielectric strength with extremely low electrical conductivity. These microvalves have been shown to have resistivities of at least 100 G.OMEGA. and are compatible with solvents such as water at a pH between 2.7 and 9.0, 1-1 propanol, acetonitrile, and acetone.

Kirby, Brian J. (San Francisco, CA); Reichmuth, David S. (Oakland, CA); Shepodd, Timothy J. (Livermore, CA)

2006-04-04T23:59:59.000Z

246

Accelerators, Beams And Physical Review Special Topics - Accelerators And Beams  

SciTech Connect (OSTI)

Accelerator science and technology have evolved as accelerators became larger and important to a broad range of science. Physical Review Special Topics - Accelerators and Beams was established to serve the accelerator community as a timely, widely circulated, international journal covering the full breadth of accelerators and beams. The history of the journal and the innovations associated with it are reviewed.

Siemann, R.H.; /SLAC

2011-10-24T23:59:59.000Z

247

Acceleration Worksheet 8/24/2011 ACCELERATION WORKSHEET  

E-Print Network [OSTI]

Acceleration Worksheet 8/24/2011 ACCELERATION WORKSHEET College of Arts and Sciences Name _____________ TO _____________ month/year month/year II. I meet the requirements for acceleration under [fill out either a) or b;Acceleration Worksheet 8/24/2011 Acceleration 2011-2012 Courses of Study The faculty of the college desires

Davis, H. Floyd

248

Neutrino physics at accelerators  

E-Print Network [OSTI]

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.

Enrique Fernandez

2006-07-16T23:59:59.000Z

249

Safety of Accelerator Facilities  

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

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.

2001-01-08T23:59:59.000Z

250

Safety of Accelerator Facilities  

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

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.

2004-07-23T23:59:59.000Z

251

Microscale acceleration history discriminators  

DOE Patents [OSTI]

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.

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

2002-01-01T23:59:59.000Z

252

Safety of Accelerator Facilities  

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

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.

2011-07-21T23:59:59.000Z

253

Accelerators (4/5)  

ScienceCinema (OSTI)

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.

None

2011-10-06T23:59:59.000Z

254

Accelerators (3/5)  

ScienceCinema (OSTI)

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.

None

2011-10-06T23:59:59.000Z

255

Accelerator Modeling with MATLAB Accelerator Toolbox  

SciTech Connect (OSTI)

This paper introduces Accelerator Toolbox (AT)--a collection of tools to model storage rings and beam transport lines in the MATLAB environment. The objective is to illustrate the flexibility and efficiency of the AT-MATLAB framework. The paper discusses three examples of problems that are analyzed frequently in connection with ring-based synchrotron light sources.

Terebilo, Andrei

2002-08-21T23:59:59.000Z

256

Collider-Accelerator Department  

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

RHIC Tunnel and Magnets RHIC Tunnel and Magnets RHIC Tunnel and Magnets AGS Tunnel and Magnets NSRL Beamline RF Kicker Snake 200-MeV LINAC AGS Cold Snake Magnet About the Collider-Accelerator Department The mission of the Collider-Accelerator Department is to develop, improve and operate the suite of particle / heavy ion accelerators used to carry out the program of accelerator-based experiments at BNL; to support the experimental program including design, construction and operation of the beam transports to the experiments plus support of detector and research needs of the experiments; to design and construct new accelerator facilities in support of the BNL and national missions. The C-A Department supports an international user community of over 1500 scientists. The department performs all these functions in an environmentally responsible and safe manner under a rigorous conduct of operations approach.

257

Ceramic-polymer nanocomposites with increased dielectric permittivity and low dielectric loss  

SciTech Connect (OSTI)

The use of lead free materials in device fabrication is very essential from environmental point of view. We have synthesized the lead free ferroelectric polymer nanocomposite films with increased dielectric properties. Lead free bismuth titanate has been used as active ceramic nanofillers having crystallite size 24nm and PVDF as the polymer matrix. Ferroelectric ?-phase of the polymer composite films was confirmed by X-ray diffraction pattern. Mapping data confirms the homogeneous dispersion of ceramic particles into the polymer matrix. Frequency dependent dielectric constant increases up to 43.4 at 100Hz, whereas dielectric loss decreases with 7 wt% bismuth titanate loading. This high dielectric constant lead free ferroelectric polymer films can be used for energy density applications.

Bhardwaj, Sumit, E-mail: sumit.bhardwaj4@gmail.com; Paul, Joginder, E-mail: sumit.bhardwaj4@gmail.com [Centre for Materials Science and Engineering, National Institute of Technology, Hamirpur -177 005 (India); Raina, K. K. [School of Physics and Materials Science, Thapar University, Patiala -147 004 (India); Thakur, N. S. [Centre for Energy and Environment, National Institute of Technology, Hamirpur -177005 (India); Kumar, Ravi [Centre for Materials Science and Engineering, National Institute of Technology, Hamirpur -177 005 (India); Beant College of Engineering and Technology, Gurdaspur -143521 (India)

2014-04-24T23:59:59.000Z

258

Electric field shielding in dielectric nanosolutions  

E-Print Network [OSTI]

To gain some insight into electrochemical activity of dielectric colloids of technical and biomedical interest we investigate a model of dielectric nanosolution whose micro-constitution is dominated by dipolarions -- positively and negatively charged spherically symmetric nano-structures composed of ionic charge surrounded by cloud of radially polarized dipoles of electrically neutral molecules of solvent. Combing the standard constitutive equations of an isotropic dielectric liquid with Maxwell equation of electrostatics and presuming the Boltzmann shape of the particle density of bound-charge we derive equation for the in-medium electrostatic field. Particular attention is given to numerical analysis of obtained analytic solutions of this equation describing the exterior fields of dipolarions with dipolar atmospheres of solvent molecules endowed with either permanent or field-induced dipole moments radially polarized by central symmetric field of counterions. The presented computations show that the electric field shielding of dipolarions in dielectric nanosolutions is quite different from that of counterionic nano-complexes of Debye-H\\"uckel theory of electrolytes.

Sergey Bastrukov; Pik-Yin Lai; Irina Molodtsova

2014-03-26T23:59:59.000Z

259

Quantum Electromagnetic Fluctuations in Inhomogeneous Dielectric Media  

E-Print Network [OSTI]

A new mathematical and computational technique for calculating quantum vacuum expectation values of energy and momentum densities associated with electromagnetic fields in bounded domains containing inhomogeneous media is discussed. This technique is illustrated by calculating the mode contributions to the difference in the vacuum force expectation between opposite ends of an inhomogeneous dielectric non-dispersive medium confined to a perfectly conducting rigid box.

Shin-itiro Goto; Robin W. Tucker; Timothy J. Walton

2011-07-07T23:59:59.000Z

260

Electromagnetic Interrogation of Dielectric Materials 1  

E-Print Network [OSTI]

Electromagnetic Interrogation of Dielectric Materials 1 H.T. Banks M.W. Buksas Center for Research grant P200A40730. #12; Abstract We investigate time domain based electromagnetic inverse problems electromagnetic phenomenon. For our purposes, we categorize the materials and the models employed to describe them

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Surface charge in dielectric barrier discharge plasma actuators  

SciTech Connect (OSTI)

Direct measurements of the dielectric surface potential and its dynamics in asymmetric dielectric barrier discharge (DBD) plasma actuators show that the charge builds up at the dielectric surface and extends far downstream of the plasma. The surface charge persists for a long time (tens of minutes) after the driving voltage has been turned off. For a sinusoidal voltage waveform, the dielectric surface charges positively. With the voltage waveform consisting of nanosecond pulses superimposed on a dc bias, the sign of the dielectric surface charge is the same as the sign (polarity) of the bias voltage. The surface charging significantly affects DBD plasma actuator performance.

Opaits, D. F.; Shneider, M. N.; Miles, Richard B. [Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544 (United States); Likhanskii, A. V. [Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Macheret, S. O. [Lockheed Martin Aeronautics Company, Palmdale, California 93599 (United States)

2008-07-15T23:59:59.000Z

262

DEDICATED HEAVY ION MEDICAL ACCELERATORS  

E-Print Network [OSTI]

Lancaster, R.B. Yourd, Pre~,Accelerator A wideroe~,Basedcarbon beam medical accelerator facility. N "' . ,;j "' ::lEat the MARIA Workshop III: Accelerator Systems for Relat ic

Gough, R.A.

2013-01-01T23:59:59.000Z

263

History of Proton Linear Accelerators  

E-Print Network [OSTI]

the board to show why the accelerator couldn't work. Then atmuch. References 1. Linear Accelerators, edited by P. M .at the 1986 Linear Accelerator Conference, SLAC, Stanford,

Alvarez, Luis W.

1986-01-01T23:59:59.000Z

264

Accelerated Least Squares Multidimensional Scaling  

E-Print Network [OSTI]

x(make_x(36,2)) xACCELERATED SCALING R EFERENCES I.ACCELERATED LEAST SQUARES MULTIDIMENSIONAL SCALING JAN DEare simpler to write. ACCELERATED SCALING It is shown in De

Leeuw, Jan de

2006-01-01T23:59:59.000Z

265

Accelerated Least Squares Multidimensional Scaling  

E-Print Network [OSTI]

x(make_x(36,2)) xACCELERATED SCALING R EFERENCES I.ACCELERATED LEAST SQUARES MULTIDIMENSIONAL SCALING JAN DEare simpler to write. ACCELERATED SCALING It is shown in De

Jan de Leeuw

2011-01-01T23:59:59.000Z

266

Accelerator Physics and Design at NERSC  

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

Accelerator Science Accelerator Science ReframAccelerator.jpg Particle accelerators are among the largest, most complex, and most important scientific instruments in the world....

267

Optimization of silver-dielectric-silver nanoshell for sensing applications  

SciTech Connect (OSTI)

In this paper, resonance light scattering (RLS) properties of a silver-dielectric-silver nanoshell, based on quasi-static approach and plasmon hybridization theory, are investigated. Scattering spectrum of silver-dielectric-silver nanoshell has two intense and clearly separated RLS peaks and provides a potential for biosensing based on surface plasmon resonance and surface-enhanced Raman scattering. The two RLS peaks in silver-dielectric-silver nanoshell are optimized by tuning the geometrical dimensions. In addition, the optimal geometry is discussed to obtain the high sensitivity of silver-dielectric-silver nanoshell. As the silver core radius increases, the sensitivity of silver-dielectric-silver nanoshell decreases whereas increasing the middle dielectric thickness increases the sensitivity of silver-dielectric-silver nanoshell.

Shirzaditabar, Farzad; Saliminasab, Maryam [Department of Physics, Razi University, Kermanshah 67144-15111 (Iran, Islamic Republic of)] [Department of Physics, Razi University, Kermanshah 67144-15111 (Iran, Islamic Republic of)

2013-08-15T23:59:59.000Z

268

Argonne Accelerator Institute  

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

AAI Home AAI Home Welcome Accelerators at Argonne Mission Organization History Document Collection Conferences & Workshops Beams and Applications Seminar Argonne-Fermilab Collaboration Lee Teng Scholarship Program Useful Links Organization The Argonne Accelerator Institute is a matrixed organization. Its members and fellows reside in programmatic Argonne divisions. The Institute reports to the Associate Laboratory Director for Photon Science), and the administrative functions of the Institute are within the PSC directorate. Director: Rodney Gerig Associate Director: Hendrik Weerts ( Director of High Energy Physics Division) Associate Director: Sasha Zholents (Director of Accelerator Systems Division) Associate Director: Robert Janssens ( Director of Argonne Physics Division)

269

Accelerator Toolbox for MATLAB  

SciTech Connect (OSTI)

This paper introduces Accelerator Toolbox (AT)--a collection of tools to model particle accelerators and beam transport lines in the MATLAB environment. At SSRL, it has become the modeling code of choice for the ongoing design and future operation of the SPEAR 3 synchrotron light source. AT was designed to take advantage of power and simplicity of MATLAB--commercially developed environment for technical computing and visualization. Many examples in this paper illustrate the advantages of the AT approach and contrast it with existing accelerator code frameworks.

Terebilo, Andrei

2001-05-29T23:59:59.000Z

270

SciTech Connect: Plasmas, Dielectrics and the Ultrafast: First...  

Office of Scientific and Technical Information (OSTI)

FACET (Facility for Advanced Accelerator and Experimental Tests) is an accelerator R&D test facility that has been recently constructed at SLAC National Accelerator Laboratory....

271

C-AD Accelerator Division  

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

Accelerator Division Accelerator Division The Accelerator Division operates and continually upgrades a complex of eight accelerators: 2 Tandem Van de Graaff electrostatic accelerators, an Electron Beam Ion Source (EBIS), a 200 MeV proton Linac, the AGS Booster, the Alternating Gradient Synchrotron (AGS), and the 2 rings of the Relativistic Heavy Ion Collider (RHIC). These machines serve user programs at the Tandems, the Brookhaven Linac Isotope Producer (BLIP), the NASA Space Radiation Laboratory (NSRL), and the 2 RHIC experiments STAR, and PHENIX. The Division also supports the development of new accelerators and accelerator components. Contact Personnel Division Head: Wolfram Fischer Deputy Head: Joe Tuozzolo Division Secretary: Anna Petway Accelerator Physics: Michael Blaskiewicz

272

Argonne Accelerator Institute  

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

Quarterly Meetings Quarterly Meetings November 29, 2011 Held at the Advanced Photon Source, Argonne, IL DOE Accelerator R&D Task Force - M. White February 17, 2010 Held at the Advanced Photon Source, Argonne, IL June 16, 2009 General Updates - R. Gerig Accelerator Developments in Physics Division - R. Janssens Proposal for Argonne SRF Facility - M. Kelly Accelerator Developments in HEP Division - W. Gai Beam Activities of the DOD Project Office-Focus on the Navy FEL - S. Biedron AAI Historical Collection - T. Fields November 24, 2008 Strategic Theme Forum Meeting - This meeting was held to gather information on the Accelerator Science and Technology Theme to establish the Argonne's Strategic Plan January 9, 2008 Opening Remarks - R. Gerig ILC Planning - J. Carwardine Argonne Participation in Project X - P. Ostroumov

273

Accelerated Currents in Superconductors  

Science Journals Connector (OSTI)

It is shown that the ratio of the accelerated currents of energy and matter induced in a superconductor by a long-wavelength electric field is equal to the chemical potential of the system.

Vinay Ambegaokar and Gerald Rickayzen

1966-02-04T23:59:59.000Z

274

Accelerator on a Chip  

ScienceCinema (OSTI)

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)

England, Joel

2014-07-16T23:59:59.000Z

275

Accelerator on a Chip  

SciTech Connect (OSTI)

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)

England, Joel

2014-06-30T23:59:59.000Z

276

Advanced Accelerator Concepts Workshop  

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

EM Structure-Based Accelerators Working Group Group-Leader: Wayne Kimura, STI Optronics (wkimura@stioptronics.com) Group-Co-leader: Steve Lidia, LBNL (SMLidia@lbl.gov)...

277

CEBAF accelerator achievements  

SciTech Connect (OSTI)

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.

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

2011-06-01T23:59:59.000Z

278

Decay of accelerated particles  

Science Journals Connector (OSTI)

We study how the decay properties of particles are changed by acceleration. It is shown that under the influence of acceleration (1) the lifetime of particles is modified and (2) new processes (such as the decay of the proton) become possible. This is illustrated by considering scalar models for the decay of muons, pions, and protons. We discuss the close conceptual relation between these processes and the Unruh effect.

Rainer Mller

1997-07-15T23:59:59.000Z

279

Breakthrough: Fermilab Accelerator Technology  

SciTech Connect (OSTI)

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.

None

2012-04-23T23:59:59.000Z

280

Breakthrough: Fermilab Accelerator Technology  

ScienceCinema (OSTI)

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.

None

2014-08-12T23:59:59.000Z

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Laser wakefield generated X-ray probe for femtosecond time-resolved measurements of ionization states of warm dense aluminum  

SciTech Connect (OSTI)

We have developed a laser wakefield generated X-ray probe to directly measure the temporal evolution of the ionization states in warm dense aluminum by means of absorption spectroscopy. As a promising alternative to the free electron excited X-ray sources, Betatron X-ray radiation, with femtosecond pulse duration, provides a new technique to diagnose femtosecond to picosecond transitions in the atomic structure. The X-ray probe system consists of an adjustable Kirkpatrick-Baez (KB) microscope for focusing the Betatron emission to a small probe spot on the sample being measured, and a flat Potassium Acid Phthalate Bragg crystal spectrometer to measure the transmitted X-ray spectrum in the region of the aluminum K-edge absorption lines. An X-ray focal spot size of around 50 ?m was achieved after reflection from the platinum-coated 10-cm-long KB microscope mirrors. Shot to shot positioning stability of the Betatron radiation was measured resulting in an rms shot to shot variation in spatial pointing on the sample of 16 ?m. The entire probe setup had a spectral resolution of ?1.5 eV, a detection bandwidth of ?24 eV, and an overall photon throughput efficiency of the order of 10{sup ?5}. Approximately 10 photons were detected by the X-ray CCD per laser shot within the spectrally resolved detection band. Thus, it is expected that hundreds of shots will be required per absorption spectrum to clearly observe the K-shell absorption features expected from the ionization states of the warm dense aluminum.

Mo, M. Z.; Chen, Z.; Tsui, Y. Y.; Fedosejevs, R. [Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta T6G 2V4 (Canada)] [Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta T6G 2V4 (Canada); Fourmaux, S.; Saraf, A.; Otani, K.; Kieffer, J. C. [INRS-EMT, Universit du Qubec, 1650 Lionel Boulet, Varennes, Qubec J3X 1S2 (Canada)] [INRS-EMT, Universit du Qubec, 1650 Lionel Boulet, Varennes, Qubec J3X 1S2 (Canada); Ng, A. [Department of Physics and Astronomy, University of British Columbia, British Columbia V6T 1Z1 (Canada)] [Department of Physics and Astronomy, University of British Columbia, British Columbia V6T 1Z1 (Canada)

2013-12-15T23:59:59.000Z

282

Modeling of 10 GeV-1 TeV laser-plasma accelerators using Lorentz booster simulations  

SciTech Connect (OSTI)

Modeling of laser-plasma wakefield accelerators in an optimal frame of reference [J.-L. Vay, Phys. Rev. Lett. 98 130405 (2007)] allows direct and e#14;fficient full-scale modeling of deeply depleted and beam loaded laser-plasma stages of 10 GeV-1 TeV (parameters not computationally accessible otherwise). This verifies the scaling of plasma accelerators to very high energies and accurately models the laser evolution and the accelerated electron beam transverse dynamics and energy spread. Over 4, 5 and 6 orders of magnitude speedup is achieved for the modeling of 10 GeV, 100 GeV and 1 TeV class stages, respectively. Agreement at the percentage level is demonstrated between simulations using different frames of reference for a 0.1 GeV class stage. Obtaining these speedups and levels of accuracy was permitted by solutions for handling data input (in particular particle and laser beams injection) and output in a relativistically boosted frame of reference, as well as mitigation of a high-frequency instability that otherwise limits effectiveness.

Vay, J.-L.; Geddes, C.G.R.; Esarey, E.; Esarey, E.; Leemans, W.P.; Cormier-Michel, E.; Grote, D.P.

2011-12-01T23:59:59.000Z

283

Advanced accelerator simulation research: miniaturizing accelerators from kilometers to meters  

E-Print Network [OSTI]

Advanced accelerator simulation research: miniaturizing accelerators from kilometers to meters W: Advanced accelerator research is aimed at finding new technologies that can dramatically reduce the size and cost of future high-energy accelerators. Supercomputing is already playing a dramatic and critical role

Geddes, Cameron Guy Robinson

284

Compensation of wakefield-driven energy spread in energy recovery linacs Georg H. Hoffstaetter and Yang Hao Lau  

E-Print Network [OSTI]

and Yang Hao Lau Cornell University, Ithaca, New York 14853, USA (Received 16 May 2008; published 23 July, so that their energy is available for the acceleration of new particles. During this deceleration at a decelerating phase to recover the particles' energy. This energy is then used to accelerate new bunches

Hoffstaetter, Georg

285

Dielectric elastomer generators that stack up  

Science Journals Connector (OSTI)

This paper reports the design, fabrication, and testing of a soft dielectric elastomer power generator with a volume of less than 1 cm3. The generator is well suited to harvest energy from ambient and from human body motion as it can harvest from low frequency (sub-Hz) motions, and is compact and lightweight. Dielectric elastomers are highly stretchable variable capacitors. Electrical energy is produced when the deformation of a stretched, charged dielectric elastomer is relaxed; like-charges are compressed together and opposite-charges are pushed apart, resulting in an increased voltage. This technology provides an opportunity to produce soft, high energy density generators with unparalleled robustness. Two major issues block this goal: current configurations require rigid frames that maintain the dielectric elastomer in a prestretched state, and high energy densities have come at the expense of short lifetime. This paper presents a self-supporting stacked generator configuration which does not require rigid frames. The generator consists of 48 generator films stacked on top of each other, resulting in a structure that fits within an 11 mm diameter footprint while containing enough active material to produce useful power. To ensure sustainable power production, we also present a mathematical model for designing the electronic control of the generator which optimizes energy production while limiting the electrical stress on the generator below failure limits. When cyclically compressed at 1.6 Hz, our generator produced 1.8 mW of power, which is sufficient for many low-power wireless sensor nodes. This performance compares favorably with similarly scaled electromagnetic, piezoelectric, and electrostatic generators. The generator's small form factor and ability to harvest useful energy from low frequency motions such as tree swaying or shoe impact provides an opportunity to deliver power to remote wireless sensor nodes or to distributed points in the human body without the need for costly periodic battery replacement.

T G McKay; S Rosset; I A Anderson; H Shea

2015-01-01T23:59:59.000Z

286

Computing Wilson lines with dielectric branes  

E-Print Network [OSTI]

Wilson lines in N=4SYM can be computed in terms of branes carrying electric flux, i.e. F-strings dissolved in their worldvolumes. It is then natural to think that those configurations are the effective description of strings expanding due to dielectric effect to D-branes. In this note we explicitly show this for a class of such configurations, namely those dual to Wilson lines either in the symmetric or in the antisymmetric tensor product of fundamentals.

Diego Rodriguez-Gomez

2006-04-05T23:59:59.000Z

287

High?frequency cutoff periodic dielectric waveguides  

Science Journals Connector (OSTI)

We report high?frequency cutoff in periodic dielectric waveguides. The guides consisted of 1?? photoresist film with a surface corrugation of up to 500 overlaid on fused silica substrates. At a wavelength of 1.064 ? we obtained transition between complete cutoff and propagation by variation in the periodicity of the guide of 30 . For gratings having 500? corrugation unobstructed propagation at 1.32 ? occurred with complete stopping of 1.064?? light.

F.W. Dabby; M.A. Saifi; A. Kestenbaum

1973-01-01T23:59:59.000Z

288

ACCELERATED IMPROVEMENT A CONCENTRATED APPROACH  

E-Print Network [OSTI]

ACCELERATED IMPROVEMENT A CONCENTRATED APPROACH FOR CONTINUOUS IMPROVEMENT #12;Accelerated.quality.wisc.edu O F F I C E O F Q U A L I T Y I M P R O V E M E N T Accelerated Improvement This guide to improving resources. You will find helpful information needed to conduct an Accelerated Improvement project

Shapiro, Vadim

289

US LHC Accelerator Research Program  

E-Print Network [OSTI]

US LHC Accelerator Research Program Instrumentation Collaboration Meeting John Marriner May 9, 2003 #12;2/14/03 US LARP Instrumentation Collaboration Mtg 2 US LARP LARP = LHC Accelerator Research Program LARP is an outgrowth of the US LHC Accelerator Project The US LHC Accelerator Project built

Large Hadron Collider Program

290

BNL | Our History: Accelerators  

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

> See also: Reactors > See also: Reactors A History of Leadership in Particle Accelerator Design Cosmotron Cosmotron (1952-1966) Early in Brookhaven Lab history, the consortium of universities responsible for founding the new research center, decided that Brookhaven should provide leading facilities for high energy physics research. In April 1948, the Atomic Energy Commission approved a plan for a proton synchrotron to be built at Brookhaven. The new machine would accelerate protons to previously unheard of energies-comparable to the cosmic rays showering the earth's outer atmosphere. It would be called the Cosmotron. The Cosmotron was the first accelerator in the world to send particles to energies in the billion electron volt, or GeV, region. The machine reached its full design energy of 3.3 GeV in 1953.

291

Accelerator Update | Archive | 2012  

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

2 Accelerator Update Archive 2 Accelerator Update Archive April 27, 2012 - April 30, 2012 NuMI reported receiving 7.67E18 protons on target for the period from 4/23/12 to 4/30/12. The Booster developed an aperture restriction that required lower beam intensity Main Injector personnel completed their last study The shutdown begins Linac, MTA, and Booster will continue using beam for one or two more weeks Linac will supply the Neutron Therapy Facility beam for most of the shutdown April 25, 2012 - April 27, 2012 Booster beam stop problem repaired Beam to all experiments will shut off at midnight on Monday morning, 4/30/12. Main Injector will continue to take beam until 6 AM on Monday morning. Linac, the Neutron Therapy Facility, MTA, and Booster will continue using beam for one or two more weeks. The Fermi Accelerator Complex will be in shutdown for approximately one year

292

ORELA accelerator facility  

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

The Oak Ridge Electron Linear Accelerator The Oak Ridge Electron Linear Accelerator Pulsed Neutron Source The ORELA is a powerful electron accelerator-based neutron source located in the Physics Division of Oak Ridge National Laboratory. It produces intense, nanosecond bursts of neutrons, each burst containing neutrons with energies from 10e-03 to 10e08 eV. ORELA is operated about 1200 hours per year and is an ORNL User Facility open to university, national laboratory and industrial scientists. The mission of ORELA has changed from a recent focus on applied research to nuclear astrophysics. This is an area in which ORELA has historically been very productive: most of the measurements of neutron capture cross sections necessary for understanding heavy element nucleosynthesis through the slow neutron capture process (s-process) have

293

Dielectric microconcentrators for efficiency enhancement in concentrator solar cells  

Science Journals Connector (OSTI)

Metal fingers typically cover more than 10% of the active area of concentrator solar cells. Microfabricated dielectric optical designs that can completely eliminate front contact...

Korech, Omer; Gordon, Jeffrey M; Katz, Eugene A; Feuermann, Daniel; Eisenberg, Naftali

2007-01-01T23:59:59.000Z

294

Dielectric nanostructures for broadband light trapping in organic solar cells  

Science Journals Connector (OSTI)

We investigate broadband light trapping using only dielectric components to improve organic solar cell efficiency. We show that substantial absorption and photocurrent enhancement is...

Raman, Aaswath; Yu, Zongfu; Fan, Shanhui

295

Understanding Sub-20nm Breakdown Behavior of Liquid Dielectrics  

Science Journals Connector (OSTI)

Nanoscale confinement of dielectric molecules is expected to influence their breakdown mechanism in applications such as nanoprobe based machining, molecular electronics, and other related technologies. This Letter presents the first experimental study of the breakdown of nonpolar, nonthiolated liquid dielectrics in the nanometer regime and develops a field emission assisted avalanche based approach to model such behavior. The studies show that dielectric breakdown in the sub-20nm regime is independent of the cathode materials and is dominated by the electron emission and atomic cluster migration due to the sub-20nm scale confinement of the liquid dielectric.

Kumar R. Virwani; Ajay P. Malshe; Kamlakar P. Rajurkar

2007-07-06T23:59:59.000Z

296

Electromagnetic field quantization in a linear dielectric medium  

E-Print Network [OSTI]

By modeling a dielectric medium with two independent reservoirs, i.e., electric and magnetic reservoirs, the electromagnetic field is quantized in a linear dielectric medium consistently. A Hamiltonian is proposed from which using the Heisenberg equations, not only the Maxwell equations but also the structural equations can be obtained. Using the Laplace transformation, the wave equation for the electromagnetic vector potential is solved in the case of a homogeneous dielectric medium. Some examples are considered showing the applicability of the model to both absorptive and nonabsorptive dielectrics.

F. Kheirandish; M. Amooshahi

2005-11-13T23:59:59.000Z

297

Interfacing to accelerator instrumentation  

SciTech Connect (OSTI)

As the sensory system for an accelerator, the beam instrumentation provides a tremendous amount of diagnostic information. Access to this information can vary from periodic spot checks by operators to high bandwidth data acquisition during studies. In this paper, example applications will illustrate the requirements on interfaces between the control system and the instrumentation hardware. A survey of the major accelerator facilities will identify the most popular interface standards. The impact of developments such as isochronous protocols and embedded digital signal processing will also be discussed.

Shea, T.J.

1995-12-31T23:59:59.000Z

298

Perimeter Institute Cosmic Acceleration  

E-Print Network [OSTI]

Wayne Hu Perimeter Institute April 2010 Cosmic Acceleration Dark Energy v. Modified Gravity #12;Outline · Dark Energy vs Modified Gravity · Three Regimes of Modified Gravity · Worked (Toy) Models: f 1998 Discovery #12;Mercury or Pluto? General relativity says Gravity = Geometry And Geometry = Matter-Energy

Hu, Wayne

299

Accelerating News Issue 5  

E-Print Network [OSTI]

In this spring issue, we look at developments towards higher luminosity and higher energy colliders. We report on the technology developed for the remote powering of the LHC magnets and studies of diagnostics based on higher order mode port signals. We also inform you about the main outcome of the TIARA survey on market needs for accelerator scientists.

Szeberenyi, A

2013-01-01T23:59:59.000Z

300

Note on accelerated detectors  

Science Journals Connector (OSTI)

The Unruh result, on the thermal-like behavior of particle detectors under a uniformly accelerated state of motion, is found by a different method which does not involve field quantization in a metric with a horizon. The result is extended to other situations.

P. Meyer

1978-07-15T23:59:59.000Z

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Acceleration of Time Integration  

SciTech Connect (OSTI)

We outline our strategies for accelerating time integration for long-running simulations, such as those for global climate modeling. The strategies target the Cray XT systems at the National Center for Computational Sciences at Oak Ridge National Laboratory. Our strategies include fully implicit, parallel-in-time, and curvelet methods.

White III, James B [ORNL; Drake, John B [ORNL; Worley, Patrick H [ORNL; Archibald, Richard K [ORNL; Evans, Katherine J [ORNL; Kothe, Douglas B [ORNL

2007-01-01T23:59:59.000Z

302

E-Print Network 3.0 - anomalous dielectric absorption Sample...  

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

Sample search results for: anomalous dielectric absorption Page: << < 1 2 3 4 5 > >> 1 PHY 7097--Optical Effects in Solids 2011 Course Syllabus Summary: dielectric function, . 3....

303

Trace formula for dielectric cavities III: TE modes  

E-Print Network [OSTI]

The construction of the semiclassical trace formula for the resonances with the transverse electric (TE) polarization for two-dimensional dielectric cavities is discussed. Special attention is given to the derivation of the two first terms of Weyl's series for the average number of such resonances. The obtained formulas agree well with numerical calculations for dielectric cavities of different shapes.

E. Bogomolny; R. Dubertrand

2012-06-15T23:59:59.000Z

304

Modeling of Field Distribution and Energy Storage in Diphasic Dielectrics  

E-Print Network [OSTI]

Modeling of Field Distribution and Energy Storage in Diphasic Dielectrics S. K. Patil, M. Y, USA Modeling of electrostatic field distribution and energy storage in diphasic dielectrics containing to the increased energy storage density. For composites with lower volume fractions of high-permittivity inclusions

Koledintseva, Marina Y.

305

Basics of Measuring the Dielectric Properties of Materials  

E-Print Network [OSTI]

......................................................................................32 #12;Introduction Every material has a unique set of electrical characteristics that are dependent for more solid designs or to monitor a manufacturing process for improved quality control. A dielectric. For example, the loss of a cable insulator, the impedance of a substrate, or the frequency of a dielectric

Anlage, Steven

306

Control of Laser Plasma Based Accelerators up to 1 GeV  

SciTech Connect (OSTI)

This dissertation documents the development of a broadband electron spectrometer (ESM) for GeV class Laser Wakefield Accelerators (LWFA), the production of high quality GeV electron beams (e-beams) for the first time in a LWFA by using a capillary discharge guide (CDG), and a statistical analysis of CDG-LWFAs. An ESM specialized for CDG-LWFAs with an unprecedented wide momentum acceptance, from 0.01 to 1.1 GeV in a single shot, has been developed. Simultaneous measurement of e-beam spectra and output laser properties as well as a large angular acceptance (> {+-} 10 mrad) were realized by employing a slitless scheme. A scintillating screen (LANEX Fast back, LANEX-FB)--camera system allowed faster than 1 Hz operation and evaluation of the spatial properties of e-beams. The design provided sufficient resolution for the whole range of the ESM (below 5% for beams with 2 mrad divergence). The calibration between light yield from LANEX-FB and total charge, and a study on the electron energy dependence (0.071 to 1.23 GeV) of LANEX-FB were performed at the Advanced light source (ALS), Lawrence Berkeley National Laboratory (LBNL). Using this calibration data, the developed ESM provided a charge measurement as well. The production of high quality electron beams up to 1 GeV from a centimeter-scale accelerator was demonstrated. The experiment used a 310 {micro}m diameter gas-filled capillary discharge waveguide that channeled relativistically-intense laser pulses (42 TW, 4.5 x 10{sup 18} W/cm{sup 2}) over 3.3 centimeters of sufficiently low density ({approx_equal} 4.3 x 10{sup 18}/cm{sup 3}) plasma. Also demonstrated was stable self-injection and acceleration at a beam energy of {approx_equal} 0.5 GeV by using a 225 {micro}m diameter capillary. Relativistically-intense laser pulses (12 TW, 1.3 x 10{sup 18}W/cm{sup 2}) were guided over 3.3 centimeters of low density ({approx_equal} 3.5 x 10{sup 18}/cm{sup 3}) plasma in this experiment. A statistical analysis of the CDG-LWFAs performance was carried out. By taking advantage of the high repetition rate experimental system, several thousands of shots were taken in a broad range of the laser and plasma parameters. An analysis program was developed to sort and select the data by specified parameters, and then to evaluate performance statistically. The analysis suggested that the generation of GeV-level beams comes from a highly unstable and regime. By having the plasma density slightly above the threshold density for self injection, (1) the longest dephasing length possible was provided, which led to the generation of high energy e-beams, and (2) the number of electrons injected into the wakefield was kept small, which led to the generation of high quality (low energy spread) e-beams by minimizing the beam loading effect on the wake. The analysis of the stable half-GeV beam regime showed the requirements for stable self injection and acceleration. A small change of discharge delay t{sub dsc}, and input energy E{sub in}, significantly affected performance. The statistical analysis provided information for future optimization, and suggested possible schemes for improvement of the stability and higher quality beam generation. A CDG-LWFA is envisioned as a construction block for the next generation accelerator, enabling significant cost and size reductions.

Nakamura, Kei

2007-12-03T23:59:59.000Z

307

Acceleration and Classical Electromagnetic Radiation  

E-Print Network [OSTI]

Classical radiation from an accelerated charge is reviewed along with the reciprocal topic of accelerated observers detecting radiation from a static charge. This review commemerates Bahram Mashhoon's 60th birthday.

E. N. Glass

2008-01-09T23:59:59.000Z

308

Charge Diagnostics for Laser Plasma Accelerators  

E-Print Network [OSTI]

the 1989 Particle Accelerator Conference, IEEE, Piscataway,Diagnostics for Laser Plasma Accelerators K . Nakamura, A .ALS) synchrotron booster accelerator. The sensitivity of the

Nakamura, K.

2011-01-01T23:59:59.000Z

309

Fermilab | Science | Particle Accelerators | Advanced Superconducting...  

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

Superconducting Test Accelerator is America's only test bed for cutting-edge particle beams and for accelerator research aimed at Intensity Frontier proton accelerators. ASTA...

310

History of Proton Linear Accelerators  

DOE R&D Accomplishments [OSTI]

Some personal recollections are presented that relate to the author`s experience developing linear accelerators, particularly for protons. (LEW)

Alvarez, L. W.

1987-01-00T23:59:59.000Z

311

Longitudinal dielectric permettivity of quantum Maxwell collisional plasmas  

E-Print Network [OSTI]

The kinetic equation of Wigner -- Vlasov -- Boltzmann with collision integral in relaxation BGK (Bhatnagar, Gross and Krook) form in coordinate space for quantum non--degenerate (Maxwellian) collisional plasma is used. Exact expression (within the limits of considered model) is found. The analysis of longitudinal dielectric permeability is done. It is shown that in the limit when Planck's constant tends to zero of expression for dielectric permettivity transforms into the classical case of dielectric permettivity. At small values of wave number it has been received the solution of the dispersion equation. Damping of plasma oscillations has been analized. The analytical comparison with the dielectric Mermin' function received with the use of the kinetic equation in momentum space is done. Graphic comparison of the real and imaginary parts of dielectric permettivity of quantum and classical plasma is done also.

A. V. Latyshev; A. A. Yushkanov

2010-03-12T23:59:59.000Z

312

"Z" Facility Dielectric Oil Clean-Up  

SciTech Connect (OSTI)

In August of 1998 the Z facility leaked approximately 150 gallons of deionized water into the dielectric oil of the Energy Storage Section (ESS). After processing the oil to remove existing particulate and free water the dielectric breakdown strength increased from the mid 20kV range to values in excess of 40 kV. 40 kV is above historical operating levels of about 35 kV. This, however, was not enough to allow 90 kV charging of the Marx Generators in the ESS. Further analysis of the oil showed dissolved water at a saturated level (70 - 80 ppm) and some residual particulate contamination smaller than 3 microns. The dissolved water and particulate combination was preventing the 90 kV charging of the Marx Generators in the ESS. After consulting with the oil industry it was determined that nitrogen sparging could be used to remove the dissolved water. Further particulate filtering was also conducted. After approximately 20 hours of sparging the water content in the ESS was reduced to 42 ppm which enabled Marx charging to 90 kV.

Alessandri, Daniel; Bloomquist, Doug; Donovan, Guy; Feltz, Greg; Grelle, Nibby; Guthrie, Doug; Harris, Mark; Horry, Mike; Lockas, Mike; Potter, Jimmy; Pritchard, Chuck; Steedly, Jim

1999-06-30T23:59:59.000Z

313

Electromagnetic Siegert states for periodic dielectric structures  

E-Print Network [OSTI]

The formalism of Siegert states to describe the resonant scattering in quantum theory is extended to the resonant scattering of electromagnetic waves on periodic dielectric arrays. The excitation of electromagnetic Siegert states by an incident wave packet and their decay is studied. The formalism is applied to develop a theory of coupled electromagnetic resonances arising in the electromagnetic scattering problem for two such arrays separated by a distance 2h (or, generally, when the physical properties of the scattering array depend on a real coupling parameter h). Analytic properties of Siegert states as functions of the coupling parameter h are established by the Regular Perturbation Theorem which is an extension the Kato-Rellich theorem to the present case. By means of this theorem, it is proved that if the scattering structure admits a bound state in the radiation continuum at a certain value of the coupling parameter h, then there always exist regions within the structure in which the near field can be amplified as much as desired by adjusting the value of h. This establishes a rather general mechanism to control and amplify optical nonlinear effects in periodically structured planar structures possessing a nonlinear dielectric susceptibility.

Friends R. Ndangali; Sergei V. Shabanov

2011-08-09T23:59:59.000Z

314

Acceleration in de Sitter spacetimes  

E-Print Network [OSTI]

We propose a definition of uniform accelerated frames in de Sitter spacetimes exploiting the Nachtmann group theoretical method of introducing coordinates on these manifolds. Requiring the transformation between the static frame and the accelerated one to depend continuously on acceleration in order to recover the well-known Rindler approach in the flat limit, we obtain a new metric with a reasonable physical meaning.

Ion I. Cotaescu

2014-07-09T23:59:59.000Z

315

Basic concepts in plasma accelerators  

Science Journals Connector (OSTI)

...plasma accelerators. Plasma accelerators are ideal...2. Relativistic plasma wave acceleration The...electric field at the focus of high-power short-pulse...Diffraction limits the depth of focus to the Rayleigh length...stimulated Brillouin and plasma modulational instabilities...

2006-01-01T23:59:59.000Z

316

Accelerator Update | Archive | 2010  

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

10 Accelerator Update Archive 10 Accelerator Update Archive December 20, 2010 - December 22, 2010 - Three stores provided !32 hours of luminosity - Problems with two Linac quadrupole power supplies - Cryo system technicians work on TEV sector D1 wet engine - TEV quench during checkout - JASMIN's run at MTest ends December 17, 2010 - December 20, 2010 The Integrated Luminosity for the period from 12/13/10 to 12/20/10 was 66.31 inverse picobarns. NuMI reported receiving 7.62E18 protons on target during this same period. - Five Stores provided ~62 hours of luminosity - Operations had trouble with a Linac RF station (LRF3) - Operators tuned the Linac backup source (I- Source) December 15, 2010 - December 17, 2010 - Three stores provided ~36.1 hours of luminosity - MI-52 Septa repaired - NuMI recovered its target LCW system

317

ACCELERATOR SAFETY ENVELOPE  

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

LCASE-001, Ver. 3 LCASE-001, Ver. 3 Linac Commissioning Accelerator Safety Envelope For the National Synchrotron Light Source II Photon Sciences Directorate Version 3 December 8, 2011 Prepared by Brookhaven National Laboratory P.O. Box 5000 Upton, NY 11973-5000 managed by Brookhaven Science Associates for the U.S. Department of Energy Office of Science Basic Energy Science under contract DE-AC02-98CD10886 Linac Commissioning Accelerator Safety Envelope (LCASE) ii Photon Sciences Directorate ii DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty,

318

Argonne Accelerator Institute  

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

CWDD - Continuous Wave Deuterium Demonstrator CWDD - Continuous Wave Deuterium Demonstrator The Continuous Wave Deuterium Demonstrator (CWDD) accelerator, a cryogenically-cooled (26K) linac, was designed to accelerate 80 mA cw of D to 7.5 MeV. CWDD was being built to demonstrate the lauching of a beam with characteristics suitable for a space-based neutral particle-beam (NPB). A considerable amount of hardware was constructed and installed in the Argonne-based facility, and major performance milestones were achieved before program funding ended in October 1993. References - Document Access Guide Continuous Wave Deuterium Demonstrator Final Design Review, Grumman Space Systems, Grumman-Culham Laboratory, Los Alamos (1989). (Located in the Argonne Research Library) Recommissioning and first operation of the CWDD injector at Argonne

319

Accelerator Update | Archive | 2009  

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

9 Accelerator Update Archive 9 Accelerator Update Archive December 18, 2009 - December 21, 2009 The integrated luminosity for the period from 12/14/09 to 12/21/09 was 51.27 inverse picobarns. NuMI reported receiving 6.38E18 protons on target during this same period. - Four stores provided ~62.25 hours of luminosity - Store 7444 had an AIL of 306E30 - BRF19 cavity suffered a vacuum failure and was removed - The Booster West Anode Power Supply suffered some problems December 16, 2009 - December 18, 2009 - Three stores provided ~45 hours of luminosity - PBar kicker problem - MI RF problems December 14, 2009 - December 16, 2009 - Four stores provided ~42 hours of luminosity - Recycler kicker repaired - Booster East Anode Power Supply trips due to BRF1, 2, & 8 December 11, 2009 - December 14, 2009

320

WIPP Accelerating Cleanup  

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

ACCELERATING CLEANUP: ACCELERATING CLEANUP: PATHS TO CLOSURE CARLSBAD AREA OFFICE JUNE 1998 I. Operations/Field Overview CAO Mission The mission of the Carlsbad Area Office (CAO) is to protect human health and the environment by opening and operating the Waste Isolation Pilot Plant (WIPP) for safe disposal of transuranic (TRU) waste and by establishing an effective system for management of TRU waste from generation to disposal. It includes personnel assigned to CAO, WIPP site operations, transportation, and other activities associated with the National TRU Program (NTP). The CAO develops and directs implementation of the TRU waste program, and assesses compliance with the program guidance, as well as the commonality of activities and assumptions among all TRU waste sites. NTP Program Management

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Argonne Accelerator Institute  

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

ZGS -- Zero Gradient Synchrotron (operation: 1963 - 1979) ZGS -- Zero Gradient Synchrotron (operation: 1963 - 1979) The ZGS was a 12 GeV weak-focusing proton synchrotron. It was the first high energy physics accelerator located between the U.S. coasts. The ZGS was also the first synchrotron to accelerate spin polarized protons and the first to use H-minus injection. Other noteworthy features of the ZGS program were the large number of university-based users and the pioneering development of large superconducting magnets for bubble chambers and beam transport. References - Document Access Guide History of the ZGS, Argonne, 1979, American Institute of Physics, AIP Conference Proceedings No. 60 (1980). (Located in the Argonne Research Library) High Energy Physics at Argonne National Laboratory, A. Crewe, R.

322

ACCELERATOR SAFETY ENVELOPE  

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

BCASE-001, Ver. 2 BCASE-001, Ver. 2 Booster Commissioning Accelerator Safety Envelope For the National Synchrotron Light Source II Photon Sciences Directorate Version 2 December 8, 2011 Prepared by Brookhaven National Laboratory P.O. Box 5000 Upton, NY 11973-5000 managed by Brookhaven Science Associates for the U.S. Department of Energy Office of Science Basic Energy Science under contract DE-AC02-98CD10886 Booster Commissioning Accelerator Safety Envelope (BCASE) ii Photon Sciences Directorate ii DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty,

323

Radiation from accelerated branes  

Science Journals Connector (OSTI)

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.

Mohab Abou-Zeid and Miguel S. Costa

2000-04-26T23:59:59.000Z

324

Review of ion accelerators  

SciTech Connect (OSTI)

The field of ion acceleration to higher energies has grown rapidly in the last years. Many new facilities as well as substantial upgrades of existing facilities have extended the mass and energy range of available beams. Perhaps more significant for the long-term development of the field has been the expansion in the applications of these beams, and the building of facilities dedicated to areas outside of nuclear physics. This review will cover many of these new developments. Emphasis will be placed on accelerators with final energies above 50 MeV/amu. Facilities such as superconducting cyclotrons and storage rings are adequately covered in other review papers, and so will not be covered here.

Alonso, J.

1990-06-01T23:59:59.000Z

325

Accelerators for Cancer Therapy  

DOE R&D Accomplishments [OSTI]

The vast majority of radiation treatments for cancerous tumors are given using electron linacs that provide both electrons and photons at several energies. Design and construction of these linacs are based on mature technology that is rapidly becoming more and more standardized and sophisticated. The use of hadrons such as neutrons, protons, alphas, or carbon, oxygen and neon ions is relatively new. Accelerators for hadron therapy are far from standardized, but the use of hadron therapy as an alternative to conventional radiation has led to significant improvements and refinements in conventional treatment techniques. This paper presents the rationale for radiation therapy, describes the accelerators used in conventional and hadron therapy, and outlines the issues that must still be resolved in the emerging field of hadron therapy.

Lennox, Arlene J.

2000-05-30T23:59:59.000Z

326

The Muon Accelerator Program  

SciTech Connect (OSTI)

Multi-TeV Muon Colliders and high intensity Neutrino Factories have captured the imagination of the particle physics community. These new types of facility both require an advanced muon source capable of producing O(10{sup 21}) muons per year. The muons must be captured within bunches, and their phase space manipulated so that they fit within the acceptance of an accelerator. In a Neutrino Factory (NF), muons from this 'front end' are accelerated to a few GeV or a few tens of GeV, and then injected into a storage ring with long straight sections. Muon decays in the straight sections produce an intense neutrino beam. In a Muon Collider (MC) the muons must be cooled by a factor O(10{sup 6}) to produce beams that are sufficiently bright to give high luminosity in the collider. Bunches of positive and negative muons are then accelerated to high energy, and injected in opposite directions into a collider ring in which they collide at one or more interaction points. Over the last decade our understanding of the concepts and technologies needed for Muon Colliders and Neutrino Factories has advanced, and it is now believed that, within a few years, with a well focused R&D effort (i) a Neutrino Factory could be proposed, and (ii) enough could be known about the technologies needed for a Muon Collider to assess the feasibility and cost of this new type of facility, and to make a detailed plan for the remaining R&D. Although these next NF and MC steps are achievable, they are also ambitious, and will require an efficient and dedicated organization to accomplish the desired goals with limited resources. The Muon Accelerator Program (MAP) has recently been created to propose and execute this R&D program.

Geer, Steve; /Fermilab; Zisman, Mike; /LBL, Berkeley

2011-08-01T23:59:59.000Z

327

Modulational effects in accelerators  

SciTech Connect (OSTI)

We discuss effects of field modulations in accelerators, specifically those that can be used for operational beam diagnostics and beam halo control. In transverse beam dynamics, combined effects of nonlinear resonances and tune modulations influence diffusion rates with applied tune modulation has been demonstrated. In the longitudinal domain, applied RF phase and voltage modulations provide mechanisms for parasitic halo transport, useful in slow crystal extraction. Experimental experiences with transverse tune and RF modulations are also discussed.

Satogata, T.

1997-12-01T23:59:59.000Z

328

Linear induction accelerator  

DOE Patents [OSTI]

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.

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

1988-06-21T23:59:59.000Z

329

Accelerate Energy Productivity 2030  

Broader source: Energy.gov [DOE]

The U.S. Department of Energy, the Council on Competitiveness, and the Alliance to Save Energy are teaming up for Accelerate Energy Productivity 2030, an initiative to double U.S. energy productivity by 2030. This effort continues support for the goal the President set in his 2013 State of the Union address to double energy productivity, measured by GDP per unit of energy use, from the 2010 level by 2030.

330

Accelerator and Beam Science, ABS, Accelerator Operations and Technology,  

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

Accelerator Concepts Accelerator Concepts Injectors Operations Physics CONTACTS Group Leader Robert Garnett Deputy Group Leader Kenneth Johnson Office Administrator Monica Sanchez Phone: (505) 667-2846 Put a short description of the graphic or its primary message here Accelerator and Beam Science The Accelerator and Beam Science (AOT-ABS) Group at Los Alamos addresses physics aspects of the driver accelerator for the LANSCE spallation neutron source and related topics. These activities are wide ranging and include generating negative and positive ions in plasma ion sources, creating ion beams from these particles, accelerating the ion beams in linear accelerator structures up to an energy of 800 MeV, compressing the negative hydrogen beam to packets of sub-microsecond duration and accumulating beam current in the Proton Storage Ring, and

331

Berkeley Proton Linear Accelerator  

DOE R&D Accomplishments [OSTI]

A linear accelerator, which increases the energy of protons from a 4 Mev Van de Graaff injector, to a final energy of 31.5 Mev, has been constructed. The accelerator consists of a cavity 40 feet long and 39 inches in diameter, excited at resonance in a longitudinal electric mode with a radio-frequency power of about 2.2 x 10{sup 6} watts peak at 202.5 mc. Acceleration is made possible by the introduction of 46 axial "drift tubes" into the cavity, which is designed such that the particles traverse the distance between the centers of successive tubes in one cycle of the r.f. power. The protons are longitudinally stable as in the synchrotron, and are stabilized transversely by the action of converging fields produced by focusing grids. The electrical cavity is constructed like an inverted airplane fuselage and is supported in a vacuum tank. Power is supplied by 9 high powered oscillators fed from a pulse generator of the artificial transmission line type.

Alvarez, L. W.; Bradner, H.; Franck, J.; Gordon, H.; Gow, J. D.; Marshall, L. C.; Oppenheimer, F. F.; Panofsky, W. K. H.; Richman, C.; Woodyard, J. R.

1953-10-13T23:59:59.000Z

332

RF Breakdown Studies Using a 1.3-GHz Text Cell  

E-Print Network [OSTI]

M. Conde, W. Gai, ANL, Argonne, IL A. Moretti, M. Popovic,experiments is planned at the Argonne Wakefield Accelerator.stand was transported to the Argonne Wakefield Accelerator (

Sah, R.

2010-01-01T23:59:59.000Z

333

Fermilab | Illinois Accelerator Research Center | Fermilab Core...  

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

Refrigeration systems Control, Interlock, and Data acquisition systems VHDL, PLD, PLC, DSP programming Accelerator Engineering Complete accelerator design, fabrication,...

334

Siemens Technology Accelerator | Open Energy Information  

Open Energy Info (EERE)

Siemens Technology Accelerator Place: Germany Sector: Services Product: General Financial & Legal Services ( Subsidiary Division ) References: Siemens Technology Accelerator1...

335

Safety of Accelerator Facilities - DOE Directives, Delegations...  

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

Health, Environmental Protection, Facility Authorization, Safety The order defines accelerators and establishes accelerator specific safety requirements and approval authorities...

336

Accelerating Clean Energy Adoption (Fact Sheet), Weatherization...  

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

Accelerating Clean Energy Adoption (Fact Sheet), Weatherization and Intergovernmental Program (WIP) Accelerating Clean Energy Adoption (Fact Sheet), Weatherization and...

337

Accelerating Energy Savings Performance Contracting Through Model...  

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

Accelerating Energy Savings Performance Contracting Through Model Statewide Programs Accelerating Energy Savings Performance Contracting Through Model Statewide Programs Provides...

338

Nonlinear dielectric response of periodic composite materials A. Kolpakov & A. K. Tagantsev & L. Berlyand &  

E-Print Network [OSTI]

periodic composite (a matrix of a large dielectric constant ferro- electric material with linear dielectric of ferroelectric/dielectric composites. A typical example is a (Ba,Sr)TiO3 ceramic fabricated with addition of MgNonlinear dielectric response of periodic composite materials A. Kolpakov & A. K. Tagantsev & L

Berlyand, Leonid

339

Inhomogeneity implies accelerated expansion  

Science Journals Connector (OSTI)

The Einstein equations for an inhomogeneous irrotational dust universe are analyzed. A set of mild assumptions, all of which are shared by the standard Friedmann-Lemaitre-Robertson-Walkertype scenarios, results in a model that depends only on the distribution of scalar spatial curvature. If the shape of this distribution is made to fit the structure of the present Universe, with most of the matter in galaxy clusters and very little in the voids that will eventually dominate the volume, then there is a period of accelerated expansion after cluster formation, even in the absence of a cosmological constant.

Harald Skarke

2014-02-10T23:59:59.000Z

340

Black holes at accelerators.  

E-Print Network [OSTI]

ar X iv :h ep -p h/ 05 11 12 8v 3 6 A pr 2 00 6 Black Holes at Accelerators Bryan Webber Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, UK In theories with large extra dimensions and TeV-scale gravity, black holes... 2000 3000 Missing ET (GeV) Ar bi tra ry S ca le p p ? QCD SUSY 5 TeV BH (n=6) 5 TeV BH (n=2) (PT > 600 GeV) (SUGRA point 5) Figure 10: Missing transverse energy for various processes at the LHC. 4.2. Event Characteristics Turning from single...

Webber, Bryan R

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Argonne Accelerator Institute  

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

Fermilab Collaboration Fermilab Collaboration Lee Teng Scholarship Program Useful Links The Argonne Accelerator Institute Historical Document Collection Document Access Guide The documents in this collection are held in several repositories, some of which have restricted access. This guide explains the different types of access, and specifies the access levels for each repository. Repositories Name Access Argonne National Laboratory Document Open Access Argonne Research Library Hard Copy Only Beam Dynamics Newsletter Open Access DOE Information Bridge Open Access IEEE Xplore Library Subscription Required JACoW Open Access Journal of Applied Physics Subscription Required Nuclear Instruments & Methods in Physics Research, Section A Subscription Required Physical Review A Subscription Required

342

Millimeter wave analysis of the dielectric properties of oil shales  

E-Print Network [OSTI]

Natural sedimentation processes give rise to fine layers in shales. If these layers alternate between organic-rich and organic-poor sediments, then the contrast in dielectric properties gives rise to an effective birefringence as the presence of hydrocarbons suppresses the dielectric constant of the host rock. We have measured these effects with a quasioptical millimeter wave setup that is rapid and noncontacting. We find that the strength of this birefringence and the overall dielectric permittivity provide two useful diagnostic of the organic content of oil shales.

John A. Scales; Michael Batzle

2006-06-06T23:59:59.000Z

343

Unusual dielectric response in cobalt doped reduced graphene oxide  

SciTech Connect (OSTI)

Intensive research on cobalt doped reduced graphene oxide (Co-RGO) to investigate the modification in graphene magnetism and spin polarization due to presence of transition metal atom has been carried out, however, its dielectric spectroscopy, particularly, how capacitance changes with impurity levels in graphene is relatively unexplored. In the present work, dielectric spectroscopy along with magneto-dielectric effect are investigated in Co-RGO. Contrary to other materials, here permittivity increases abruptly with frequency in the low frequency region and continues to increase till 10{sup 7}?Hz. This unusual behavior is explained on the basis of trap induced capacitance created due to impurity levels.

Akhtar, Abu Jahid; Gupta, Abhisek; Kumar Shaw, Bikash; Saha, Shyamal K., E-mail: cnssks@iacs.res.in [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032 (India)

2013-12-09T23:59:59.000Z

344

Spherical cloaking using multilayer shells of ordinary dielectrics  

SciTech Connect (OSTI)

An approach for spherical cloaking using multilayer ordinary dielectric materials has been developed. The total scattering cross section (TSCS) of the spherical multilayer shell with metallic core was derived based on the Mie theory. The dielectric profile of the shell was optimized to minimize the TSCS of the cloaked target. The specific directions, at which the scattering could be practically eliminated, were detected. The influence of the target size and the dielectric material loss on the cloaking efficiency was analyzed. It was shown that the cloaking efficiency for larger targets could be improved by employing lossy materials in the shell.

Wang, Xiaohui; Chen, Fang; Semouchkina, Elena, E-mail: esemouch@mtu.edu [Department of Electrical and Computer Engineering, Michigan Technological University, Houghton, MI, 49931 (United States)] [Department of Electrical and Computer Engineering, Michigan Technological University, Houghton, MI, 49931 (United States)

2013-11-15T23:59:59.000Z

345

Magnetically coupled electromagnetically induced transparency analogy of dielectric metamaterial  

SciTech Connect (OSTI)

In this manuscript, we experimentally demonstrate magnetically coupled electromagnetically induced transparency (EIT) analogy effect inside dielectric metamaterial. In contrast to previous studies employed different metallic topological microstructures to introduce dissipation loss change, barium strontium titanate, and calcium titanate (CaTiO{sub 3}) are chosen as the bright and dark EIT resonators, respectively, due to their different intrinsic dielectric loss. Under incident magnetic field excitation, dielectric metamaterial exhibits an EIT-type transparency window around 8.9?GHz, which is accompanied by abrupt change of transmission phase. Numerical calculations show good agreement with experiment spectra and reveal remarkably increased group index, indicating potential application in slow light.

Zhang, Fuli, E-mail: fuli.zhang@nwpu.edu.cn; He, Xuan [Key Laboratory of Space Applied Physics and Chemistry, Ministry of Education and Department of Applied Physics, School of Science, Northwestern Polytechnical University, Xi'an 710072 (China); Zhao, Qian [State Key Laboratory of Tribology, Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China); Lan, Chuwen; Zhou, Ji [State Key Laboratory of New Ceramics and Fine Processing, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Zhang, Weihong, E-mail: zhangwh@nwpu.edu.cn; Qiu, Kepeng [School of Mechanical Engineering, P.O. Box 552, Northwestern Polytechnical University, Xi'an 710072 (China)

2014-03-31T23:59:59.000Z

346

Magnetic Insulation for Electrostatic Accelerators  

SciTech Connect (OSTI)

The voltage gradient which can be sustained between electrodes without electrical breakdowns is usually one of the most important parameters in determining the performance which can be obtained in an electrostatic accelerator. We have recently proposed a technique which might permit reliable operation of electrostatic accelerators at higher electric field gradients, perhaps also with less time required for the conditioning process in such accelerators. The idea is to run an electric current through each accelerator stage so as to produce a magnetic field which envelopes each electrode and its electrically conducting support structures. Having the magnetic field everywhere parallel to the conducting surfaces in the accelerator should impede the emission of electrons, and inhibit their ability to acquire energy from the electric field, thus reducing the chance that local electron emission will initiate an arc. A relatively simple experiment to assess this technique is being planned. If successful, this technique might eventually find applicability in electrostatic accelerators for fusion and other applications.

Grisham, L. R. [Princeton Plasma Physics Laboratory, P. O. Box 451, Princeton, New Jersey 08543 (United States)

2011-09-26T23:59:59.000Z

347

Modern electron accelerators for radiography  

SciTech Connect (OSTI)

Over the past dozen years or so there have been significant advances in electron accelerators designed specifically for radiography of hydrodynamic experiments. Accelerator technology has evolved to accomodate the radiographers' contitiuing quest for multiple images in t h e and space:, improvements in electron beam quality have resulted in smaller radiographic spot sizes for better resolution, while higher radiation do% now provides imprcwed penetration of large, dense objects. Inductive isolation and acceleration techniques have played a ley rob in these advances.

Ekdahl, C. A. (Carl A.)

2001-01-01T23:59:59.000Z

348

Accelerating and Retarding Anomalous Diffusion  

E-Print Network [OSTI]

In this paper Gaussian models of retarded and accelerated anomalous diffusion are considered. Stochastic differential equations of fractional order driven by single or multiple fractional Gaussian noise terms are introduced to describe retarding and accelerating subdiffusion and superdiffusion. Short and long time asymptotic limits of the mean squared displacement of the stochastic processes associated with the solutions of these equations are studied. Specific cases of these equations are shown to provide possible descriptions of retarding or accelerating anomalous diffusion.

Chai Hok Eab; S. C. Lim

2012-01-14T23:59:59.000Z

349

Keer electro-optic measurements in liquid dielectrics  

E-Print Network [OSTI]

Kerr electro-optic technique has been used to measure the electric field distribution in high voltage stressed dielectric liquids, where the difference between refractive indices for light polarized parallel and perpendicular ...

Zhang, Xuewei

2014-01-01T23:59:59.000Z

350

Development of dielectric elastomer actuators for MRI devices  

E-Print Network [OSTI]

Dielectric elastomer (DE) actuators are an emerging class of polymer actuation devices. They exhibit large strains and have high force and energy densities. They can be designed in a variety of geometries and are inexpensive ...

Vogan, John D. (John DeWayne), 1979-

2004-01-01T23:59:59.000Z

351

Materials for freeform fabrication of GHz tunable dielectric photonic crystals.  

SciTech Connect (OSTI)

Photonic crystals are of interest for GHz transmission applications, including rapid switching, GHz filters, and phased-array technology. 3D fabrication by Robocasting enables moldless printing of high solid loading slurries into structures such as the ''woodpile'' structures used to fabricate dielectric photonic band gap crystals. In this work, tunable dielectric materials were developed and printed into woodpile structures via solid freeform fabrication (SFF) toward demonstration of tunable photonic crystals. Barium strontium titanate ceramics possess interesting electrical properties including high permittivity, low loss, and high tunability. This paper discusses the processing route and dielectric characterization of (BaxSr1-XTiO3):MgO ceramic composites, toward fabrication of tunable dielectric photonic band gap crystals.

Niehaus, Michael Keith; Lewis, Jennifer A. (University of Illinois, Urbana, IL); Smay, James Earl; Clem, Paul Gilbert; Lin, Shawn-Yu; Cesarano, Joseph, III (,; ); Carroll, James F.

2003-01-01T23:59:59.000Z

352

Surface-PlasmonoDielectric-polaritonic devices and systems  

DOE Patents [OSTI]

There is provided a structure for supporting propagation of surface plasmon polaritons. The structure includes a plasmonic material region and a dielectric material region, disposed adjacent to a selected surface of the plasmonic material region. At least one of the plasmonic material region and the dielectric material region have a dielectric permittivity distribution that is specified as a function of depth through the corresponding material region. This dielectric permittivity distribution is selected to impose prespecified group velocities, v.sub.gj, on a dispersion relation for a surface polaritonic mode of the structure for at least one of a corresponding set of prespecified frequencies, .omega..sub.j, and corresponding set of prespecified wavevectors, where j=1 to N.

Karalis, Aristeidis; Joannopoulos, John; Soljacic, Marin

2013-06-25T23:59:59.000Z

353

Atmospheric Plasma Sterilization and Deodorization of Dielectric Surfaces  

Science Journals Connector (OSTI)

A method is presented for rapid and uniform sterilization and deodorization of dielectric surfaces. The technology is applicable to the inside surface of PET or glass bottles, polymer caps, plast...

P. Koulik; S. Begounov; S. Goloviatinskii

1999-06-01T23:59:59.000Z

354

Characteristics Of A Dielectric Barrier Discharge In Atmospheric Air  

SciTech Connect (OSTI)

Parallel plate dielectric barrier discharges consisting of two electrodes with glass (epsilon{sub r} = 7.5) and alumina (epsilon{sub r} = 9.0) as the dielectric barrier were constructed. The system is powered by a variable 20 kV high voltage supply which is capable of delivering unipolar voltage pulses at frequency of 0.1-2.5 kHz and sinusoidal voltages at 6.5 kHz and above. At atmospheric pressure, the discharges exhibit either diffuse or filamentary appearance depending on parameters which include the series capacitance established by the electrodes with the dielectric barrier and varying air gap, dielectric material, and frequency of the supply voltages. This DBD system is built for the study of bacterial sterilization.

Lai, C. K.; Chin, O. H. [Plasma Research Laboratory, Physics Department, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia); Thong, K. L. [Microbiology Division, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia)

2009-07-07T23:59:59.000Z

355

Ferroelectric and dielectric properties of strontium bismuth niobate vanadates  

E-Print Network [OSTI]

Ferroelectric and dielectric properties of strontium bismuth niobate vanadates Yun Wu and Guozhong 19 November 1999; accepted 20 April 2000) Strontium bismuth niobate vanadates, SrBi2(VxNb1-x)2O9

Cao, Guozhong

356

Dielectric reciprocity theorem analogous to the Betti-Maxwell theorem  

Science Journals Connector (OSTI)

A reciprocity theorem is stated which applies to a dielectric medium at rest polarized by one or the other of two systems of charges. Its formulation is similar to the Betti-Maxwell reciprocity theorem for elastic media.

B. Blaive and J. Metzger

1984-10-01T23:59:59.000Z

357

Electromagnetic Inverse Problems Involving Distributions of Dielectric Mechanisms and Parameters  

E-Print Network [OSTI]

Electromagnetic Inverse Problems Involving Distributions of Dielectric Mechanisms and Parameters H University, Raleigh, NC 27695-8205 August 17, 2005 Abstract We consider electromagnetic interrogation, uniform, log-normal, and log-Bi-Gaussian distributions. Keywords: Electromagnetic interrogation

358

Dielectric based resonant guided wave networks Eyal Feigenbaum1,*  

E-Print Network [OSTI]

Dielectric based resonant guided wave networks Eyal Feigenbaum1,* and Harry A. Atwater1 1 Thomas J. 285(6), 46­55 (2001). 2. J. D. Joannopoulos, S. G. Johnson, J. N. Winn, and R. D. Meade, Photonic

Atwater, Harry

359

Challenges in Accelerator Beam Instrumentation  

SciTech Connect (OSTI)

The challenges in beam instrumentation and diagnostics for present and future particle accelerator projects are presented. A few examples for advanced hadron and lepton beam diagnostics are given.

Wendt, M.

2009-12-01T23:59:59.000Z

360

High field gradient particle accelerator  

DOE Patents [OSTI]

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.

Nation, J.A.; Greenwald, S.

1989-05-30T23:59:59.000Z

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

High field gradient particle accelerator  

DOE Patents [OSTI]

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.

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

1989-01-01T23:59:59.000Z

362

Advances in CTIX Accelerator Study  

Science Journals Connector (OSTI)

Several new experiments have been conducted on the UC Davis repetitive-pulsed spheromak-like compact toroid (SCT) accelerator (CTIX...

D. Q. Hwang; R. D. Horton; S. Howard; R. W. Evans

2007-06-01T23:59:59.000Z

363

Accelerating Combined Heat & Power Deployment  

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

ACCELERATING COMBINED HEAT & POWER DEPLOYMENT An Industry Consultation by the United States Energy Association August 31, 2011 Cover Photograph: CHP Plant at the Mueller Energy...

364

Non-Paraxial Accelerating Beams  

E-Print Network [OSTI]

We present the spatially accelerating solutions of the Maxwell equations. Such non-paraxial beams accelerate in a circular trajectory, thus generalizing the concept of Airy beams. For both TE and TM polarizations, the beams exhibit shape-preserving bending with sub-wavelength features, and the Poynting vector of the main lobe displays a turn of more than 90 degrees. We show that these accelerating beams are self-healing, analyze their properties, and compare to the paraxial Airy beams. Finally, we present the new family of periodic accelerating beams which can be constructed from our solutions.

Ido Kaminer; Rivka Bekenstein; Jonathan Nemirovsky; Mordechai Segev

2012-02-03T23:59:59.000Z

365

Accelerate Energy Productivity 2030 Launch  

Office of Energy Efficiency and Renewable Energy (EERE)

Today, the Department of Energy kicked off Accelerate Energy Productivity 2030. This initiative supports President Obamas goal to double our energy productivity by 2030.

366

Encapsulation methods and dielectric layers for organic electrical devices  

DOE Patents [OSTI]

The disclosure provides methods and materials suitable for use as encapsulation barriers and dielectric layers in electronic devices. In one embodiment, for example, there is provided an electroluminescent device or other electronic device with a dielectric layer comprising alternating layers of a silicon-containing bonding material and a ceramic material. The methods provide, for example, electronic devices with increased stability and shelf-life. The invention is useful, for example, in the field of microelectronic devices.

Blum, Yigal D; Chu, William Siu-Keung; MacQueen, David Brent; Shi, Yijan

2013-07-02T23:59:59.000Z

367

Dielectric Properties of Strontium Titanate at Low Temperature  

Science Journals Connector (OSTI)

The dielectric properties of annealed single crystals of SrTiO3 have been measured over the temperature range from 5 to 300 K. At temperatures below 50 K, electric double hysteresis loops are observed and associated changes in weak-field permittivity under dc bias have been measured. It is shown that a phenomenological analysis based on the simple Kittel function accounts satisfactorily for many aspects of the dielectric behavior of SrTiO3 crystals.

M. A. Saifi and L. E. Cross

1970-08-01T23:59:59.000Z

368

Charge regulation and local dielectric function in planar polyelectrolyte brushes  

E-Print Network [OSTI]

Understanding the effect of inhomogeneity on the charge regulation and dielectric properties, and how it depends on the conformational characteristics of the macromolecules is a long-standing problem. In order to address this problem, we have developed a field-theory to study charge regulation and local dielectric function in planar polyelectrolyte brushes. The theory is used to study a polyacid brush, which is comprised of chains end-grafted at the solid-fluid interface, in equilibrium with a bulk solution containing monovalent salt ions, solvent molecules and pH controlling acid. In particular, we focus on the effects of the concentration of added salt and pH of the bulk in determining the local charge and dielectric function. Our theoretical investigations reveal that the dipole moment of the ion-pairs formed as a result of counterion adsorption on the chain backbones play a key role in affecting the local dielectric function. For polyelectrolytes made of monomers having dipole moments lower than the solvent molecules, dielectric decrement is predicted inside the brush region. However, the formation of ion-pairs (due to adsorption of counterions coming from the dissociation of added salt) more polar than the solvent molecules is shown to increase the magnitude of the dielectric function with respect to its bulk value. Furthermore, an increase in the bulk salt concentration is shown to increase the local charge inside the brush region.

Rajeev Kumar; Bobby G. Sumpter; S. Michael Kilbey II

2012-06-20T23:59:59.000Z

369

Science Accelerator : User Login  

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

Login Login The Science Accelerator ALERTS feature will automatically update you regarding newly available information in your specific area(s) of interest. Simply register for the service, then create a search strategy which will be run against information added to . Select a schedule (weekly, monthly, etc.) for receiving the email Alerts. If you are a new patron, Register to learn how to set up Alerts to meet your needs. If you are an existing patron, enter your user name and password in the boxes to login. Once logged in, you may review or modify your search, add a new search and see recent Alerts results. User Name: Password: Remember Me Remember me on this computer. Login Don't have a user name? Register! Forgot your password? Reset your password Alerts The Alerts function allows you to monitor a topic and receive timely

370

Science Accelerator : Your Selections  

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

Your Selections Back To Previous Page Selections - of First Page Previous Page Next Page Last Page Back To Previous Page You have 0 selections. Click the checkboxes clipping.addClipping on the results or alert results pages to add to your selections. Some links on this page may take you to non-federal websites. Their policies may differ from this site. U.S. Department of Energy U.S. Department of Energy Office of Science Office of Scientific and Technical Information Website Policies/Important Links Science Accelerator science.gov WorldWideScience.org Deep Web Technologies Email Results Use this form to email your search results * Email this to: * Your Name: Comments: URL only?: Number of results: 10 20 50 100 200 All Email Format: HTML TEXT * Required field Print Results

371

Accelerated overlap fermions  

Science Journals Connector (OSTI)

Numerical evaluation of the overlap Dirac operator is difficult since it contains the sign function ?(Hw) of the Hermitian Wilson-Dirac operator Hw with a negative mass term. The problems are due to Hw having very small eigenvalues on the equilibrium background configurations generated in current day Monte Carlo simulations. Since these are a consequence of the lattice discretization and do not occur in the continuum version of the operator, we investigate in this paper to what extent the numerical evaluation of the overlap can be accelerated by making the Wilson-Dirac operator more continuum-like. Specifically, we study the effect of including the clover term in the Wilson-Dirac operator and smearing the link variables in the irrelevant terms. In doing so, we have obtained a factor of 2 speedup by moving from the Wilson action to a fat link irrelevant clover action as the overlap kernel.

Waseem Kamleh; David H. Adams; Derek B. Leinweber; Anthony G. Williams

2002-07-09T23:59:59.000Z

372

Muon Collider Progress: Accelerators  

SciTech Connect (OSTI)

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 10{sup 34} cm{sup 2}s{sup 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.

Zisman, Michael S.

2011-09-10T23:59:59.000Z

373

Laser acceleration of ion beams  

E-Print Network [OSTI]

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.

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

2007-02-01T23:59:59.000Z

374

General purpose programmable accelerator board  

DOE Patents [OSTI]

A general purpose accelerator board and acceleration method comprising use of: one or more programmable logic devices; a plurality of memory blocks; bus interface for communicating data between the memory blocks and devices external to the board; and dynamic programming capabilities for providing logic to the programmable logic device to be executed on data in the memory blocks.

Robertson, Perry J. (Albuquerque, NM); Witzke, Edward L. (Edgewood, NM)

2001-01-01T23:59:59.000Z

375

SPEAR3 Accelerator Physics Update  

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

SPEAR3 ACCELERATOR PHYSICS UPDATE* SPEAR3 ACCELERATOR PHYSICS UPDATE* J. Safranek # , W.J. Corbett, R. Hettel, X. Huang, Y. Nosochkov, J. Sebek, A. Terebilo, SSRL/SLAC, Menlo Park, CA, U.S.A. Abstract The SPEAR3 [1,2] storage ring at Stanford Synchrotron Radiation Laboratory has been delivering photon beams for three years. We will give an overview of recent and ongoing accelerator physics activities, including 500 mA fills, work toward top-off injection, long-term orbit stability characterization and improvement, fast orbit feedback, new chicane optics, low alpha optics & short bunches, low emittance optics, and MATLAB software. The accelerator physics group has a strong program to characterize and improve SPEAR3 performance. INTRODUCTION In this summary of the past three years of accelerator

376

Thomas Jefferson National Accelerator Facility Site Tour - Accelerator Map  

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

Counting House Free Electron Accelerator Facility Machine Control Center Physics Storage Building North Linear Accelerator South Linear Accelerator VEPCO Substation Machine Control Center Annex Machine Control Center Annex II North Access Building South Access Building Central Helium Liquefier Injector Hall A Truck Ramp Hall B Truck Ramp Hall C Truck Ramp Experimental Hall A Experimental Hall B Experimental Hall C East Arc West Arc Counting House Free Electron Accelerator Facility Machine Control Center Physics Storage Building North Linear Accelerator South Linear Accelerator VEPCO Substation Machine Control Center Annex Machine Control Center Annex II North Access Building South Access Building Central Helium Liquefier Injector Hall A Truck Ramp Hall B Truck Ramp Hall C Truck Ramp Experimental Hall A Experimental Hall B Experimental Hall C East Arc West Arc Science Education Jefferson Lab Jefferson Lab Home Search Jefferson Lab Contact Jefferson Lab Science Education Home Teacher Resources Student Zone Games and Puzzles Science Cinema Programs and Events Search Education Privacy and Security Notice Jefferson Lab Site Tour Guided Tour Site Map Accelerator Area Map Administrative Area Map Tour Index

377

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

E-Print Network [OSTI]

al. 2005 Impact of SciDAC on accelerator projects across the171; Spentzouris P 2006 Accelerator modeling under SciDAC:of next-generation accelerator design, analysis, and

Spentzouris, Panagiotis

2008-01-01T23:59:59.000Z

378

EXOTIC MAGNETS FOR ACCELERATORS.  

SciTech Connect (OSTI)

Over the last few years, several novel magnet designs have been introduced to meet the requirements of new, high performance accelerators and beam lines. For example, the FAIR project at GSI requires superconducting magnets ramped at high rates ({approx} 4 T/s) in order to achieve the design intensity. Magnets for the RIA and FAIR projects and for the next generation of LHC interaction regions will need to withstand high doses of radiation. Helical magnets are required to maintain and control the polarization of high energy protons at RHIC. In other cases, novel magnets have been designed in response to limited budgets and space. For example, it is planned to use combined function superconducting magnets for the 50 GeV proton transport line at J-PARC to satisfy both budget and performance requirements. Novel coil winding methods have been developed for short, large aperture magnets such as those used in the insertion region upgrade at BEPC. This paper will highlight the novel features of these exotic magnets.

WANDERER, P.

2005-09-18T23:59:59.000Z

379

RFQ accelerator tuning system  

DOE Patents [OSTI]

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.

Bolie, Victor W. (Albuquerque, NM)

1990-01-01T23:59:59.000Z

380

RFQ accelerator tuning system  

DOE Patents [OSTI]

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.

Bolie, V.W.

1990-07-03T23:59:59.000Z

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

RESEARCH ON HIGH BEAM-CURRENT ACCELERATORS  

E-Print Network [OSTI]

and M. Wilson, Particle Accelerators 10, 223 13. A. I.Proc. 1976 Proton Linear Accelerator Conf. , Chalk River,and D. Keefe, Particle Accelerators~' 23. S. Humphries, J.

Keefe, Denis

2014-01-01T23:59:59.000Z

382

CALCIUM SULFATE-INDUCED ACCELERATED CORROSION  

E-Print Network [OSTI]

10286 CALCIUM SULFATE-INDUCED ACCELERATED CORROSION HilaryCT Calcium Sulf(1teinduced Accelerated Corrosion By Hilaryof the Caso - induced accelerated attack on pure iron and

Akuezue, Hilary Chikezie

2013-01-01T23:59:59.000Z

383

Terahertz-driven linear electron acceleration  

E-Print Network [OSTI]

The cost, size and availability of electron accelerators is dominated by the achievable accelerating gradient. Conventional high-brightness radio-frequency (RF) accelerating structures operate with 30-50 MeV/m gradients. Electron accelerators driven with optical or infrared sources have demonstrated accelerating gradients orders of magnitude above that achievable with conventional RF structures. However, laser-driven electron accelerators require intense sources and suffer from low bunch charge, sub-micron tolerances and sub-femtosecond timing requirements due to the short wavelength of operation. Here, we demonstrate the first linear acceleration of electrons with keV energy gain using optically-generated terahertz (THz) pulses. THz-driven accelerating structures enable high-gradient electron accelerators with simple accelerating structures, high repetition rates and significant charge per bunch. Increasing the operational frequency of accelerators into the THz band allows for greatly increased accelerating ...

Nanni, Emilio Alessandro; Ravi, Koustuban; Fallahi, Arya; Moriena, Gustavo; Miller, R J Dwayne; Krtner, Franz X

2014-01-01T23:59:59.000Z

384

Application of particle accelerators in research  

Science Journals Connector (OSTI)

......prospectives is presented. Accelerators in research are widely...to solid state, nuclear and atomic physics...bunches-multi bunch accelerator) and decrease the...In a multi-bunch accelerator, separate vacuum chambers are needed......

Giovanni Mazzitelli

2011-07-01T23:59:59.000Z

385

Pulse - Accelerator Science in Medicine  

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

t he future of accelerator physics isn’t just for physicists. As in the past, tomorrow’s discoveries in particle accelerator science may lead to unexpected applications for medical diagnosis, healing and the understanding of human biology. t he future of accelerator physics isn’t just for physicists. As in the past, tomorrow’s discoveries in particle accelerator science may lead to unexpected applications for medical diagnosis, healing and the understanding of human biology. Breakthroughs in the technology of superconducting magnets, nanometer beams, laser instrumentation and information technology will give high-energy physicists new accelerators to explore the deepest secrets of the universe: the ultimate structure of matter and the nature of space and time. But breakthroughs in accelerator science may do more than advance the exploration of particles and forces. No field of science is an island. Physics, astronomy, chemistry, biology, medicine— all interact in the continuing human endeavor to explore and understand our world and ourselves. Research at high-energy physics laboratories will lead to the next generation of particle accelerators—and perhaps to new tools for medical science.

386

PROTON ACCELERATION AT OBLIQUE SHOCKS  

SciTech Connect (OSTI)

Acceleration at the shock waves propagating oblique to the magnetic field is studied using a recently developed theoretical/numerical model. The model assumes that resonant hydromagnetic wave-particle interaction is the most important physical mechanism relevant to motion and acceleration of particles as well as to excitation and damping of waves. The treatment of plasma and waves is self-consistent and time dependent. The model uses conservation laws and resonance conditions to find where waves will be generated or damped, and hence particles will be pitch-angle-scattered. The total distribution is included in the model and neither introduction of separate population of seed particles nor some ad hoc escape rate of accelerated particles is needed. Results of the study show agreement with diffusive shock acceleration models in the prediction of power spectra for accelerated particles in the upstream region. However, they also reveal the presence of spectral break in the high-energy part of the spectra. The role of the second-order Fermi-like acceleration at the initial stage of the acceleration is discussed. The test case used in the paper is based on ISEE-3 data collected for the shock of 1978 November 12.

Galinsky, V. L.; Shevchenko, V. I., E-mail: vit@ucsd.edu [ECE Department, UC San Diego, MC 407, La Jolla, CA 92093-0407 (United States)

2011-06-20T23:59:59.000Z

387

Cosmic Particle Acceleration: Basic Issues  

E-Print Network [OSTI]

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.

T. W. Jones

2000-12-22T23:59:59.000Z

388

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)

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

Shiltsev, V.; Piot, P.

2013-09-01T23:59:59.000Z

389

An Accelerator Control Middle Layer Using MATLAB  

E-Print Network [OSTI]

Accelerator Modeling with MATLAB Accelerator Toolbox, PACChannel Access Toolbox for Matlab," ICALEPCS 2001. [4] J.Orbit Control Using MATLAB, PAC 2001. [5] J. Safranek, G.

Portmann, Gregory J.; Corbett, Jeff; Terebilo, Andrei

2005-01-01T23:59:59.000Z

390

Development of Artificial Ash Accelerated Accumulation Test ...  

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

Artificial Ash Accelerated Accumulation Test Development of Artificial Ash Accelerated Accumulation Test Poster presented at the 16th Directions in Engine-Efficiency and Emissions...

391

Chevrolet Malibu HEV Accelerated Testing - June 2013  

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

Malibu HEV Accelerated Testing - June 2013 Four model year 2013 Chevrolet Malibu hybrid electric vehicles (HEVs) entered Accelerated testing during November 2012 in a fleet in...

392

Comparing Accelerated Testing and Outdoor Exposure | Department...  

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

Comparing Accelerated Testing and Outdoor Exposure Comparing Accelerated Testing and Outdoor Exposure Presented at the PV Module Reliability Workshop, February 26 - 27 2013,...

393

Accelerated Testing Validation | Department of Energy  

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

Accelerated Testing Validation Accelerated Testing Validation Presented at the Department of Energy Fuel Cell Projects Kickoff Meeting, September 1 - October 1, 2009...

394

Hyundai Sonata HEV Accelerated Testing - March 2013  

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

Hyundai Sonata HEV Accelerated Testing - March 2013 Two model year 2011 Hyundai Sonata hybrid electric vehicles (HEVs) entered Accelerated testing during June 2011 in a fleet in...

395

CRAD, Occupational Safety & Health - Idaho Accelerated Retrieval...  

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

Occupational Safety & Health - Idaho Accelerated Retrieval Project Phase II CRAD, Occupational Safety & Health - Idaho Accelerated Retrieval Project Phase II February 2006 A...

396

RDC receives award for Accelerate Program  

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

Issues submit RDC receives award for Accelerate Program Accelerate is designed to help graduate more technical career students, place them in jobs, and better prepare them...

397

SLAC National Accelerator Laboratory Technology Marketing Summaries...  

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

SLAC National Accelerator Laboratory Technology Marketing Summaries Here you'll find marketing summaries for technologies available for licensing from the SLAC National Accelerator...

398

Early Days of Accelerator Mass Spectrometry  

DOE R&D Accomplishments [OSTI]

Alvarez reviews his role in the development of the tandem Van de Graaff accelerator and the technique of accelerator mass spectrometry as a technique for isotope dating. (GHT)

Alvarez, L. W.

1981-05-00T23:59:59.000Z

399

Independent Oversight Inspection, Stanford Linear Accelerator...  

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

Stanford Linear Accelerator Center - January 2007 January 2007 Inspection of Environment, Safety, and Health Programs at the Stanford Linear Accelerator Center This report...

400

Lab announces Venture Acceleration Fund recipients  

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

Inc., and ThermaSun Inc. as recipients of awards from the Los Alamos National Security, LLC Venture Acceleration Fund. The Laboratory's Venture Acceleration Fund provides...

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

BNL | Accelerators for Applied Research  

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

Accelerators for Applied Research Accelerators for Applied Research Brookhaven National Lab operates several accelerator facilities dedicated to applied research. These facilities directly address questions and concerns on a tremendous range of fields, including medical imaging, cancer therapy, computation, and space exploration. Leading scientists lend their expertise to these accelerators and offer crucial assistant to collaborating researchers, pushing the limits of science and technology. Interested in gaining access to these facilities for research? See the contact number listed for each facility. RHIC tunnel Brookhaven Linac Isotope Producer The Brookhaven Linac Isoptope Producer (BLIP)-positioned at the forefront of research into radioisotopes used in cancer treatment and diagnosis-produces commercially unavailable radioisotopes for use by the

402

Accelerating and rotating black holes  

E-Print Network [OSTI]

An exact solution of Einstein's equations which represents a pair of accelerating and rotating black holes (a generalised form of the spinning C-metric) is presented. The starting point is a form of the Plebanski-Demianski metric which, in addition to the usual parameters, explicitly includes parameters which describe the acceleration and angular velocity of the sources. This is transformed to a form which explicitly contains the known special cases for either rotating or accelerating black holes. Electromagnetic charges and a NUT parameter are included, the relation between the NUT parameter $l$ and the Plebanski-Demianski parameter $n$ is given, and the physical meaning of all parameters is clarified. The possibility of finding an accelerating NUT solution is also discussed.

J. B. Griffiths; J. Podolsky

2005-07-06T23:59:59.000Z

403

Polarimeter for an Accelerated Spheromak.  

E-Print Network [OSTI]

??A three-beam heterodyne polarimeter has been designed and constructed to measure line-integrated density and Faraday rotation of accelerated spheromak plasmas in the Plasma Injector 1 (more)

Carle, PATRICK

2014-01-01T23:59:59.000Z

404

Market Acceleration | Department of Energy  

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

Market Acceleration Market Acceleration Market Acceleration Photo of several men on a floating platform that is lowering monitoring tools into the ocean. The Water Power Program works to foster a commercial market for marine and hydrokinetic (MHK) energy devices in order to achieve its goal of the nation obtaining 15% of its electricity needs from all types of water power by 2030. Though marine and hydrokinetic energy is still in its infancy, the program is developing a robust portfolio of projects to accelerate wave, tidal and current project deployments and development of the MHK market in general. These projects include project siting activities, market assessments, environmental impact analyses, and research supporting technology commercialization. Learn more about the Water Power Program's work in the following areas of

405

Parameter Identification for a Dispersive Dielectric in 2D Electromagnetics: Forward and Inverse  

E-Print Network [OSTI]

Parameter Identification for a Dispersive Dielectric in 2D Electromagnetics: Forward and Inverse with a Debye dielectric slab and PML absorbing boundaries. This system assumes that the electric #12;Parameter

406

Broad band invisibility cloak made of normal dielectric multilayer  

Science Journals Connector (OSTI)

We present the design fabrication and performance test of a quasi three-dimensional carpet cloak made of normal dielectric in the microwave regime. Taking advantage of a simple linear coordinate transformation we design a carpet cloak with homogeneous anisotropic medium and then practically realize the device with multilayer of alternating normal dielectric slabs based on the effective medium theory. As a proof-of-concept example we fabricate the carpet cloak with multilayer of FR4 dielectric slabs with air spacing. The performance of the fabricated design is verified through full-wave numerical simulation and measurement of the far-field scattering electromagnetic waves in a microwave anechoic chamber. Experimental results have demonstrated pronounced cloaking effect in a very broad band from 8 GHz to 18 GHz (whole X and Ku band) due to the low loss non-dispersive feature of the multilayerdielectricstructure.

Xiaofei Xu; Yijun Feng; Shuai Xiong; Jinlong Fan; Jun-Ming Zhao; Tian Jiang

2011-01-01T23:59:59.000Z

407

Dielectric supported radio-frequency cavities  

DOE Patents [OSTI]

A device which improves the electrical and thermomechanical performance of an RF cavity, for example, in a disk-loaded accelerating structure. A washer made of polycrystalline diamond is brazed in the middle to a copper disk washer and at the outer edge to the plane wave transformer tank wall, thus dissipating heat from the copper disk to the outer tank wall while at the same time providing strong mechanical support to the metal disk. The washer structure eliminates the longitudinal connecting rods and cooling channels used in the currently available cavities, and as a result minimizes problems such as shunt impedance degradation and field distortion in the plane wave transformer, and mechanical deflection and uneven cooling of the disk assembly.

Yu, David U. L. (Rancho Palos Verdes, CA); Lee, Terry G. (Cupertino, CA)

2000-01-01T23:59:59.000Z

408

Nonlocal theory of accelerated observers  

Science Journals Connector (OSTI)

A nonlocal theory of accelerated observers is developed on the basis of the hypothesis that an electromagnetic wave can never stand completely still with respect to an observer. In the eikonal approximation, the nonlocal theory reduces to the standard extension of Lorentz invariance to accelerated observers. The validity of the nonlocal theory would exclude the possibility of existence of any basic scalar field in nature. The observational consequences of this theory are briefly discussed.

Bahram Mashhoon

1993-05-01T23:59:59.000Z

409

SPEAR3 Accelerator Physics Update  

SciTech Connect (OSTI)

The SPEAR3 storage ring at Stanford Synchrotron Radiation Laboratory has been delivering photon beams for three years. We will give an overview of recent and ongoing accelerator physics activities, including 500 mA fills, work toward top-off injection, long-term orbit stability characterization and improvement, fast orbit feedback, new chicane optics, low alpha optics & short bunches, low emittance optics, and MATLAB software. The accelerator physics group has a strong program to characterize and improve SPEAR3 performance

Safranek, James A.; Corbett, W.Jeff; Gierman, S.; Hettel, R.O.; Huang, X.; Nosochkov, Yuri; Sebek, Jim; Terebilo, Andrei; /SLAC

2007-11-02T23:59:59.000Z

410

Sequentially pulsed traveling wave accelerator  

DOE Patents [OSTI]

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.

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

2009-08-18T23:59:59.000Z

411

Teleportation with Multiple Accelerated Partners  

E-Print Network [OSTI]

As the current revolution in communication is underway, quantum teleportation can increase the level of security in quantum communication applications. In this paper, we present a quantum teleportation procedure that capable to teleport either accelerated or non-accelerated information through different quantum channels. These quantum chan- nels are based on accelerated multi-qubit states, where each qubit of each of these channels represent a partner. Namely, these states are the the W state, Greenberger-Horne-Zeilinger (GHZ) state, and the GHZ-like state. Here, we show that the fidelity of teleporting acceler- ated information is higher than the fidelity of teleporting non-accelerated information, both through a quantum channel that is based on accelerated state. Also, the comparison among the performance of these three channels shows that the degree of fidelity depends on type of the used channel, type of the measurement, and value of the acceleration. The result of comparison concludes that teleporting information through channel that is based on the GHZ state is more robust than teleporting information through channels that are based on the other two states. For future work, the proposed procedure can be generalized later to achieve communication through a wider quantum network.

Alaa Sagheer; Hala Hamdoun

2014-01-31T23:59:59.000Z

412

Millimeter wave analysis of the dielectric properties of oil shales  

Science Journals Connector (OSTI)

Natural sedimentation processes give rise to fine layers in shales. If these layers alternate between organic-rich and organic-poor sediments then the contrast in dielectric properties gives rise to an effective birefringence as the presence of hydrocarbons suppresses the dielectric constant of the host rock. We have measured these effects with a quasioptical millimeter wave setup that is rapid and noncontacting. We find that the strength of this birefringence and the overall dielectricpermittivity provide two useful diagnostics of the organic content of oil shales.

John A. Scales; Michael Batzle

2006-01-01T23:59:59.000Z

413

Aerogel and ferroelectric dielectric materials for plasma actuators  

Science Journals Connector (OSTI)

This paper presents performance evaluation of two thick materials with extreme permittivity as dielectric barrier discharge actuators. Specifically, the use of silica aerogels and ferroelectrics is investigated. Due to high polarizability of the ferroelectric material the supplied power manifests itself primarily as heat generation with no measurable thrust. The silica aerogel, however, has a significant impact on thrust saturation as compared with other dielectrics reported to date. Specifically, the silica aerogel is found to have an order of magnitude better thrust to actuator weight ratio than acrylic and twice than that of Kapton with no power penalty, making it potentially useful for small vehicle applications.

Ryan Durscher; Subrata Roy

2012-01-01T23:59:59.000Z

414

Cathode fall measurement in a dielectric barrier discharge in helium  

SciTech Connect (OSTI)

A method based on the zero-length voltage extrapolation is proposed to measure cathode fall in a dielectric barrier discharge. Starting, stable, and discharge-maintaining voltages were measured to obtain the extrapolation zero-length voltage. Under our experimental conditions, the zero-length voltage gave a cathode fall of about 185 V. Based on the known thickness of the cathode fall region, the spatial distribution of the electric field strength in dielectric barrier discharge in atmospheric helium is determined. The strong cathode fall with a maximum field value of approximately 9.25 kV/cm was typical for the glow mode of the discharge.

Hao, Yanpeng; Zheng, Bin; Liu, Yaoge [School of Electric Power, South China University of Technology, Guangzhou 510640 (China)] [School of Electric Power, South China University of Technology, Guangzhou 510640 (China)

2013-11-15T23:59:59.000Z

415

Dielectric behavior of barium modified strontium bismuth titanate ceramic  

SciTech Connect (OSTI)

Barium Modified Strontium Bismuth Titanate(SBT) ceramic with general formula Sr1?xBaxBi4Ti4O15 is prepared by solid state reaction route. The structural analysis of the ceramics was done by X-ray diffraction technique. The X-ray patterns show that all the compositions are of single phase with orthorhombic structure. The temperature dependent dielectric behavior shows that the transition temperature decreases with Ba content but the maximum dielectric constant increases. The decreases of the transition with increase in Ba{sup 2+} ion, may be due to the decrease of orthorhombicity by the incorporation of Ba{sup 2+} ion in SBT lattice.

Nayak, P., E-mail: priyambada.pce@gmail.com [Department of Physics, National Institute of Technology, Rourkela, Odisha-769008 (India); Badapanda, T. [Department of Physics, C.V. Raman College of Engineering, Bhubaneswar, Odisha-752054 (India); Anwar, S.; Panigrahi, S. [Colloids and Materials Chemistry, Institute of Minerals and Materials Technology, Bhubaneswar, Odisha-751013 (India)

2014-04-24T23:59:59.000Z

416

Alternative Gate Dielectrics on Semiconductors for MOSFET Device Applications  

SciTech Connect (OSTI)

We have investigated the synthesis and properties of deposited oxides on Si and Ge for use as alternative gate dielectrics in MOSFET applications. The capacitance and leakage current behavior of polycrystalline Y{sub 2}O{sub 3} films synthesized by pulsed-laser deposition is reported. In addition, we also discuss the growth of epitaxial oxide structures. In particular, we have investigated the use of silicide termination for oxide growth on (001) Si using laser-molecular beam epitaxy. In addition, we discuss a novel approach involving the use of hydrogen to eliminate native oxide during initial dielectric oxide nucleation on (001) Ge.

Norton, D.P.; Budai, J.D.; Chisholm, M.F.; Pennycook, S.J.; McKee, R.; Walker, F.; Lee, Y.; Park, C.

1999-12-06T23:59:59.000Z

417

Electromagnetic Field Quantization in Time-Dependent Dielectric Media  

E-Print Network [OSTI]

We present a Gupta-Bleuler quantization scheme for the electromagnetic field in time-dependent dielectric media. Starting from the Maxwell equations, a generalization of the Lorentz gauge condition adapted to time varying dielectrics is derived. Using this gauge, a Gupta-Bleuler approach to quantize all polarizations of the radiation field and the corresponding constraint condition are introduced. This new approach is different from the quantized electromagnetic field in vacuum in the sense that here the contributions of unphysical photons cannot be thoroughly eliminated, which further lead to a surface charge density. Finally, a discussion of potential experimental tests and possible implication is also made.

Xiao-Min Bei; Zhong-Zhu Liu

2011-04-18T23:59:59.000Z

418

Rectification of evanescent heat transfer between dielectric-coated and uncoated silicon carbide plates  

E-Print Network [OSTI]

Rectification of evanescent heat transfer between dielectric-coated and uncoated silicon carbide://jap.aip.org/authors #12;Rectification of evanescent heat transfer between dielectric-coated and uncoated silicon carbide-infinite bodies of the dielectric-coated silicon carbide and uncoated silicon carbide. The permittivity

Fan, Shanhui

419

Dielectric nonlinearity and stochastic effects in strontium titanate Alp T. Findikoglua)  

E-Print Network [OSTI]

Dielectric nonlinearity and stochastic effects in strontium titanate Alp T. Findikoglua) Materials-film superconducting YBa2Cu3O7 electrodes. The substrate is strontium titanate, whose nonlinear dielectric properties American Institute of Physics. DOI: 10.1063/1.1477278 Nonlinear dielectrics such as strontium titanate STO

Lythe, Grant

420

ACCELERATED DESTRUCTIVE DEGRADATION TESTS: DATA, MODELS,  

E-Print Network [OSTI]

ACCELERATED DESTRUCTIVE DEGRADATION TESTS: DATA, MODELS, AND ANALYSIS Luis A. Escobar Dept are often accelerated by testing at higher than usual levels of accelerating variables like temperature. This chapter describes an important class of models for accelerated destructive degradation data. We use

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Accelerators: powering cutting-edge research  

E-Print Network [OSTI]

Accelerators: powering cutting-edge research #12;What is a particle accelerator? Booster ourselves. Particle accelerators are our attempt to turn back the clock and see into the early stages of the Universe. They accelerate everyday charged particles (electrons or protons) to close to the speed of light

Crowther, Paul

422

US LHC Accelerator Project and Research Program  

E-Print Network [OSTI]

US LHC Accelerator Project and Research Program Jim Strait Fermilab 13 June 2002 brookhaven - fermilab - berkeley US LHC ACCELERATOR PROJECT #12;13 June 2002 J. Strait - US LHC Accelerator Project 2 Outline US LHC Accelerator (Construction) Project Project Technical and Schedule Status Cost and Schedule

Large Hadron Collider Program

423

Ultra-high vacuum photoelectron linear accelerator  

DOE Patents [OSTI]

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.

Yu, David U.L.; Luo, Yan

2013-07-16T23:59:59.000Z

424

Desired Improvements in Laser-Plasma Accelerators  

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

experiment: one CO2-driven SWABSiC prebunches the beam, the other one diagnoses Laser and Beam Damage: Dielectrics vs. Metals vs. Semiconductors From Du and Byer (1999)....

425

Theory of factors limiting high gradient operation of warm accelerating structures  

SciTech Connect (OSTI)

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.

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

2014-07-25T23:59:59.000Z

426

Pulse - Accelerator Science in Medicine  

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

t the forefront of biomedical research, medical scientists use particle accelerators to explore the structure of biological molecules. They use the energy that charged particles emit when accelerated to nearly the speed of light to create one of the brightest lights on earth, 30 times more powerful than the sun and focused on a pinpoint. t the forefront of biomedical research, medical scientists use particle accelerators to explore the structure of biological molecules. They use the energy that charged particles emit when accelerated to nearly the speed of light to create one of the brightest lights on earth, 30 times more powerful than the sun and focused on a pinpoint. Deciphering the structure of proteins is key to understanding biological processes and healing disease. To determine a protein’s structure, researchers direct the beam from an accelerator called a synchrotron through a protein crystal. The crystal scatters the beam onto a detector. From the pattern of scattering, computers calculate the position of every atom in the protein molecule and create a 3-D image of the molecule.

427

Derivation of Hamiltonians for accelerators  

SciTech Connect (OSTI)

In this report various forms of the Hamiltonian for particle motion in an accelerator will be derived. Except where noted, the treatment will apply generally to linear and circular accelerators, storage rings, and beamlines. The generic term accelerator will be used to refer to any of these devices. The author will use the usual accelerator coordinate system, which will be introduced first, along with a list of handy formulas. He then starts from the general Hamiltonian for a particle in an electromagnetic field, using the accelerator coordinate system, with time t as independent variable. He switches to a form more convenient for most purposes using the distance s along the reference orbit as independent variable. In section 2, formulas will be derived for the vector potentials that describe the various lattice components. In sections 3, 4, and 5, special forms of the Hamiltonian will be derived for transverse horizontal and vertical motion, for longitudinal motion, and for synchrobetatron coupling of horizontal and longitudinal motions. Hamiltonians will be expanded to fourth order in the variables.

Symon, K.R.

1997-09-12T23:59:59.000Z

428

High-frequency expansion of the plasma dielectric tensor  

Science Journals Connector (OSTI)

We derive high-frequency sum-rule expansion for the transverse elements of the plasma dielectric tensor. The correlation contribution to the ?-4 sum-rule coefficient has a sign opposite to that of the longitudinal element. In addition, photon contributions add to the coefficient.

G. Kalman and R. Genga

1986-01-01T23:59:59.000Z

429

Dielectric nanostructures for broadband light trapping in organic solar cells  

E-Print Network [OSTI]

Dielectric nanostructures for broadband light trapping in organic solar cells Aaswath Raman, Zongfu light trapping configuration for thin-film solar cells," Appl. Phys. Lett. 91, 243501 (2007). 8. M@stanford.edu Abstract: Organic bulk heterojunction solar cells are a promising candidate for low-cost next

Fan, Shanhui

430

SNAPSNAPSuperNova/Acceleration Probe Dark Energy and the Accelerating Universe  

E-Print Network [OSTI]

Nova/Acceleration Probe Dark Energy and the Accelerating Universe SNAP #12;he recent discovery that the expansionSNAPSNAPSuperNova/Acceleration Probe Dark Energy and the Accelerating Universe Super attraction alone, its rate of expansion would be slowing. Acceleration requires a strange "dark energy

Perlmutter, Saul

431

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

E-Print Network [OSTI]

#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

Wechsler, Risa H.

432

Market Acceleration | Department of Energy  

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

Market Acceleration Market Acceleration Market Acceleration Photo of the Wanapum Dam. Hydropower contributes significantly to the nation's renewable energy portfolio; over the last decade, the United States obtained nearly 7% of its electricity from hydropower sources. Already the largest source of renewable electricity in the United States, there remains a vast untapped resource potential in hydropower. To achieve its vision of supporting 15% of our nation's electricity needs from water power by 2030, the Water Power Program works to address environmental and regulatory barriers that prevent significant amounts of deployment; to assess and quantify the value of hydropower to the nation's electric grid and its ability to integrate other variable renewable energy technologies; and to develop a vibrant U.S.

433

Symposium on accelerator mass spectrometry  

SciTech Connect (OSTI)

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.

None

1981-01-01T23:59:59.000Z

434

Substrate dielectric effects on graphene field effect transistors  

SciTech Connect (OSTI)

Graphene is emerging as a promising material for future electronics and optoelectronics applications due to its unique electronic structure. Understanding the graphene-dielectric interaction is of vital importance for the development of graphene field effect transistors (FETs) and other novel graphene devices. Here, we extend the exploration of substrate dielectrics from conventionally used thermally grown SiO{sub 2} and hexagonal boron nitride films to technologically relevant deposited dielectrics used in semiconductor industry. A systematic analysis of morphology and optical and electrical properties was performed to study the effects of different substrates (SiO{sub 2}, HfO{sub 2}, Al{sub 2}O{sub 3}, tetraethyl orthosilicate (TEOS)-oxide, and Si{sub 3}N{sub 4}) on the carrier transport of chemical vapor deposition-derived graphene FET devices. As baseline, we use graphene FETs fabricated on thermal SiO{sub 2} with a relatively high carrier mobility of 10?000 cm{sup 2}/(V s). Among the deposited dielectrics studied, silicon nitride showed the highest mobility, comparable to the properties of graphene fabricated on thermal SiO{sub 2}. We conclude that this result comes from lower long range scattering and short range scattering rates in the nitride compared those in the other deposited films. The carrier fluctuation caused by substrates, however, seems to be the main contributing factor for mobility degradation, as a universal mobility-disorder density product is observed for all the dielectrics examined. The extrinsic doping trend is further confirmed by Raman spectra. We also provide, for the first time, correlation between the intensity ratio of G peak and 2D peak in the Raman spectra to the carrier mobility of graphene for different substrates.

Hu, Zhaoying; Prasad Sinha, Dhiraj; Ung Lee, Ji, E-mail: jlee1@albany.edu; Liehr, Michael [College of Nanoscale Science and Engineering, The State University of New York at Albany, Albany, New York 12203 (United States)

2014-05-21T23:59:59.000Z

435

Dielectric Torque and Orientation Dynamics of Liquid Crystals with Dielectric Dispersion S. V. Shiyanovskii,1,2  

E-Print Network [OSTI]

, and reorientation of the permanent molecular dipoles. The characteristic relaxation times of the first two processes field causes director reorientation, which in its turn changes the dielectric coupling between the field in the classical electro- magnetic theory results in the following dependence [6]: D t "0Et "0 Z t ÿ1 t; t0 Et0

Lavrentovich, Oleg D.

436

Transfer equation in accelerated media  

Science Journals Connector (OSTI)

The transfer equation for photons is obtained from the Lindquist formalism in curvilinear coordinates (no symmetry assumed), in an arbitrary frame and in any basis (natural or physical), to first order in O(v/c). Acceleration terms in the fluid are introduced via a modification of the metric tensor. The local tetrad attached to the accelerated fluid element follows a Fermi-Walker transport. Lorentz transformations are used to transform locally the equation from Lagrangian to Eulerian space-time coordinates. The resulting equation agrees in the case of a local Minkowskian space with the equation obtained directly using special-relativistic considerations.

Alain Munier

1986-04-15T23:59:59.000Z

437

OpenMP for Accelerators  

SciTech Connect (OSTI)

OpenMP [13] is the dominant programming model for shared-memory parallelism in C, C++ and Fortran due to its easy-to-use directive-based style, portability and broad support by compiler vendors. Similar characteristics are needed for a programming model for devices such as GPUs and DSPs that are gaining popularity to accelerate compute-intensive application regions. This paper presents extensions to OpenMP that provide that programming model. Our results demonstrate that a high-level programming model can provide accelerated performance comparable to hand-coded implementations in CUDA.

Beyer, J C; Stotzer, E J; Hart, A; de Supinski, B R

2011-03-15T23:59:59.000Z

438

Muon Acceleration R and D  

SciTech Connect (OSTI)

An intense muon source can be built in stages to support a uniquely broad program in high energy physics. Starting with a low-energy cooled muon beam, extraordinarily precise lepton flavor violation experiments are possible. Upgrading the facility with acceleration and a muon storage ring, one can build a Neutrino Factory that would allow a neutrino mixing physics program with unprecedented precision. Adding further acceleration and a collider ring, an energy-frontier muon collider can explore electroweak symmetry breaking and open a window to new physics.

Torun, Yagmur [Illinois Institute of Technology, Chicago (United States)

2009-12-17T23:59:59.000Z

439

Electron Cloud Effects in Accelerators  

SciTech Connect (OSTI)

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].

Furman, M.A.

2012-11-30T23:59:59.000Z

440

Relativistic tunneling and accelerated transmission  

E-Print Network [OSTI]

We obtain the solutions for the tunneling zone of a one-dimensional electrostatic potential in the relativistic (Dirac to Klein-Gordon) wave equation regime when the incoming wave packet exhibits the possibility of being almost totally transmitted through the potential barrier. The conditions for the occurrence of accelerated and, eventually, superluminal tunneling transmission probabilities are all quantified and the problematic superluminal interpretation originated from the study based on non-relativistic dynamics of tunneling is overcome. The treatment of the problem suggests revealing insights into condensed-matter experiments using electrostatic barriers in single- and bi-layer graphene, for which the accelerated tunneling effect deserves a more careful investigation.

Alex E. Bernardini

2007-06-26T23:59:59.000Z

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Accelerated Aging of Roofing Surfaces  

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

Accelerated aging of roofing surfaces Accelerated aging of roofing surfaces Hugo Destaillats, Ph.D. Lawrence Berkeley National Laboratory HDestaillats@LBL.gov (510) 486-5897 http://HeatIsland.LBL.gov April 4, 2013 Development of Advanced Building Envelope Surface Materials & Integration of Artificial Soiling and Weathering in a Commercial Weatherometer New York Times, 30 July 2009 2010 2012 Challenge: speed the development of high performance building envelope materials that resist soiling, maintain high solar reflectance, and save energy 2 | Building Technologies Office eere.energy.gov

442

X-ray driven channeling acceleration in crystals and carbon nanotubes  

SciTech Connect (OSTI)

Acceleration of particles channeling in a crystal by means of diffracted x-rays via Bormann anomalous transmission was conceived for heavy ions and muons by Tajima and Cavenago [Phys. Rev. Lett. 59, 1440 (1987)], which potentially offers an appreciably high field gradient on the order of GV/cm. The theoretical model of the high gradient acceleration has been studied in two kinds of atomic structure, crystals and carbon nanotubes (CNTs), with analytic calculations and electromagnetic eigenmode simulations. A range of acceleration gradients and cutoffs of the x-ray power (the lowest power limit to overcome the Bremsstrahlung radiation losses) are characterized in terms of the lattice constants, unit cell sizes, and photon energies. The parametric analysis indicates that the required x-ray power can be reduced to an order of megawatt by replacing crystals with CNTs. Eventually, the equivalent dielectric approximation of a multi-wall nanotube shows that 250810 MeV muons can be synchronously coupled with x-rays of 0.651.32 keV in the accelerating structure.

Shin, Young-Min [Department of Physics, Northern Illinois Center for Accelerator and Detector Development (NICADD), Northern Illinois University, Dekalb, Illinois 60115 (United States) [Department of Physics, Northern Illinois Center for Accelerator and Detector Development (NICADD), Northern Illinois University, Dekalb, Illinois 60115 (United States); Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States); Still, Dean A.; Shiltsev, Vladimir [Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States)] [Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States)

2013-12-15T23:59:59.000Z

443

Accelerated BS/DPT Program Academic Policy and Procedure Manual 1 ACCELERATED HEALTH STUDIES /  

E-Print Network [OSTI]

_____________________________________________________________________________________ Accelerated BS/DPT Program Academic Policy and Procedure Manual 1 ACCELERATED HEALTH STUDIES / DOCTOR OF PHYSICAL;_____________________________________________________________________________________ Accelerated BS/DPT Program Academic Policy and Procedure Manual 2 TABLE OF CONTENTS Department Personnel

Guenther, Frank

444

Tapered plasma channels to phase-lock accelerating and focusing forces in laser-plasma accelerators  

E-Print Network [OSTI]

elds in laser plasma accelerators using higher order modes,collider, in Advanced Accelerator Concepts, edited by C. B.forces in laser-plasma accelerators W. Rittershofer, 1, a)

Rittershofer, W.

2010-01-01T23:59:59.000Z

445

The Physics of Cosmic Acceleration  

E-Print Network [OSTI]

by Annual Reviews. All rights reserved 0163-8998/09/1123-0397$20.00 Key Words cosmology, dark energy · Our comprehensive search FurtherANNUAL REVIEWS #12;Dark energy: a negative-pressure fluid comprising, particle theory, gravitational theory Abstract The discovery that the cosmic expansion is accelerating has

Weijgaert, Rien van de

446

Accelerating Development in the Americas  

E-Print Network [OSTI]

for governments and as a strategic tool for development strategies; · Creating reference cases and best practices by making them feel useful, but also that of their families. OAS & MICROSOFT Accelerating Sustainable for the economic development of our countries as it is part of the process of globalisation and therefore

Narasayya, Vivek

447

Accelerators for Intensity Frontier Research  

SciTech Connect (OSTI)

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.

Derwent, Paul; /Fermilab

2012-05-11T23:59:59.000Z

448

Decoherence in an accelerated universe  

Science Journals Connector (OSTI)

In this paper we study the decoherence of the semiclassical branches of an accelerated universe. We use a third quantization formalism to analyze the decoherence between two branches of a parent universe caused by their interaction with the vacuum fluctuations of the space-time and with other parent universes in a multiverse scenario.

S. Robles-Prez; A. Alonso-Serrano; P. F. Gonzlez-Daz

2012-03-14T23:59:59.000Z

449

Physics Needs for Future Accelerators  

E-Print Network [OSTI]

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

Joseph D. Lykken

2000-01-30T23:59:59.000Z

450

Repair of overheating linear accelerator  

SciTech Connect (OSTI)

Los Alamos Neutron Science Center (LANSCE) is a proton accelerator that produces high energy particle beams for experiments. These beams include neutrons and protons for diverse uses including radiography, isotope production, small feature study, lattice vibrations and material science. The Drift Tube Linear Accelerator (DTL) is the first portion of a half mile long linear section of accelerator that raises the beam energy from 750 keV to 100 MeV. In its 31st year of operation (2003), the DTL experienced serious issues. The first problem was the inability to maintain resonant frequency at full power. The second problem was increased occurrences of over-temperature failure of cooling hoses. These shortcomings led to an investigation during the 2003 yearly preventative maintenance shutdown that showed evidence of excessive heating: discolored interior tank walls and coper oxide deposition in the cooling circuits. Since overheating was suspected to be caused by compromised heat transfer, improving that was the focus of the repair effort. Investigations revealed copper oxide flow inhibition and iron oxide scale build up. Acid cleaning was implemented with careful attention to protection of the base metal, selection of components to clean and minimization of exposure times. The effort has been very successful in bringing the accelerator through a complete eight month run cycle allowing an incredible array of scientific experiments to be completed this year (2003-2004). This paper will describe the systems, investigation analysis, repair, return to production and conclusion.

Barkley, Walter; Baldwin, William; Bennett, Gloria; Bitteker, Leo; Borden, Michael; Casados, Jeff; Fitzgerald, Daniel; Gorman, Fred; Johnson, Kenneth; Kurennoy, Sergey; Martinez, Alberto; OHara, James; Perez, Edward; Roller, Brandon; Rybarcyk, Lawrence; Stark, Peter; Stockton, Jerry

2004-01-01T23:59:59.000Z

451

Petawatt pulsed-power accelerator  

DOE Patents [OSTI]

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.

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

452

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).

453

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

SciTech Connect (OSTI)

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.

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

454

THE DEVELOPMENT OF HEAVY-ION ACCELERATORS AS DRIVERS FOR INERTIALLY CONFINED FUSION  

E-Print Network [OSTI]

HEAVY ION ACCELERATORS Principal Components . . . . .Ion Sources Pre-accelerators Low-beta Accelerators Sain Accelerators Rf Linacs . . .

Herrmannsfeldt, W.b.

2010-01-01T23:59:59.000Z

455

Conception design of helium ion FFAG accelerator with induction accelerating cavity  

E-Print Network [OSTI]

In the recent decades of particle accelerator R&D area, fixed field alternating gradient (FFAG) accelerator has become a highlight for some advantages of its higher beam intensity and lower cost, although there are still some technical challenges. In this paper, FFAG accelerator is adopted to accelerate helium ion beam on the one hand for the study of helium embrittlement on fusion reactor envelope material and on the other hand for promoting the conception research and design of FFAG accelerator and exploring the possibility of developing high power FFAG accelerators. The conventional period focusing unit of helium ion FFAG accelerator and three-dimensional model of the large aperture combinatorial magnet by OPERA-TOSCA are given. For low energy and low revolution frequency, induction acceleration is proposed to replace conventional radio frequency(RF) acceleration for helium ion FFAG accelerator, which avoids the potential breakdown of acceleration field caused by wake field and improves the acceleratio...

Huan-li, Luo; Xiang-qi, Wang; Hong-Liang, Xu

2013-01-01T23:59:59.000Z

456

Conduction of Electricity by Dielectric Liquids at High Field Strengths  

Science Journals Connector (OSTI)

The conductivity of highly purified heptane has been measured between optical flats at field strengths up to 600,000 volts per cm at temperatures ranging from - 190C to 20C. Electrode separations down to 0.005 cm were used in order to minimize the effect of space charge and ionic recombination. It is concluded that electronic or collision processes are unlikely as the source of high field conductivity in heptane and probably most other liquid dielectrics as well. It is suggested that the highly nonconducting dielectric liquids should be included as extreme cases in the general class of weak electrolytes. The presence of appreciable conductivity under high electric fields is ascribed to the lowering of the energy of the hydrogen bond by the applied field.

H. J. Plumley

1941-01-15T23:59:59.000Z

457

Numerical Regularization of Electromagnetic Quantum Fluctuations in Inhomogeneous Dielectric Media  

E-Print Network [OSTI]

Electromagnetic Casimir stresses are of relevance to many technologies based on mesoscopic devices such as MEMS embedded in dielectric media, Casimir induced friction in nano-machinery, micro-fluidics and molecular electronics. Computation of such stresses based on cavity QED generally require numerical analysis based on a regularization process. A new scheme is described that has the potential for wide applicability to systems involving realistic inhomogeneous media. From a knowledge of the spectrum of the stationary modes of the electromagnetic field the scheme is illustrated by estimating numerically the Casimir stress on opposite faces of a pair of perfectly conducting planes separated by a vacuum and the change in this result when the region between the plates is filled with an incompressible inhomogeneous non-dispersive dielectric.

Shin-itiro Goto; Alison C. Hale; Robin W. Tucker; Timothy J. Walton

2012-01-05T23:59:59.000Z

458

A novel design of dielectric perfect invisibility devices  

Science Journals Connector (OSTI)

The aim of an invisibility device is to guide light around any object put inside being able to hide objects from sight. In this work we propose a novel design of dielectric invisibility media based on negative refraction and optical conformal mapping that seems to create perfect invisibility. This design has some advantages and more relaxed constraints compared with already proposed schemes. In particular it represents an example where the time delay in a dielectric invisibility device is zero. Furthermore due to the impedance matching of negatively refracting materials the reflection should be close to zero. These findings strongly indicate that perfect invisibility with optically isotropic materials is possible. Finally the area of the invisible space is also discussed.

T. Ochiai; U. Leonhardt; J. C. Nacher

2008-01-01T23:59:59.000Z

459

Accelerator on a Chip: How It Works  

SciTech Connect (OSTI)

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.

None

2014-06-30T23:59:59.000Z

460

Reactor accelerator coupling experiments: a feasability study  

E-Print Network [OSTI]

The Reactor Accelerator Coupling Experiments (RACE) are a set of neutron source driven subcritical experiments under temperature feedback conditions. These experiments will involve coupling an accelerator driven neutron source to a TRIGA reactor...

Woddi Venkat Krishna, Taraknath

2006-08-16T23:59:59.000Z

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Cryogenic technology boosts linear accelerator capability  

Science Journals Connector (OSTI)

Cryogenic technology boosts linear accelerator capability ... Two critical properties of matter at cryogenic temperaturessuperconductivity and superfluidityshould open the way for a major advance in electron linear accelerator capability. ...

1968-05-06T23:59:59.000Z

462

LASER-PLASMA-ACCELERATOR-BASED GAMMA GAMMA COLLIDERS  

E-Print Network [OSTI]

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

Schroeder, C. B.

2010-01-01T23:59:59.000Z

463

ACCELERATORS: ENGINES FOR TRAVERSING A LARGE AND OFTEN DIFFICULT LANDSCAPE  

E-Print Network [OSTI]

of California. ACCELERATORS: ENGINES FOR TRAVERSING A LARGEand Andre Lebedev Abstract TYPES OF ACCELERATORS The manyapplications of accelerators are presented, with pictures

Sessler, Andrew M.

2014-01-01T23:59:59.000Z

464

Staging laser plasma accelerators for increased beam energy  

E-Print Network [OSTI]

Staging Laser Plasma Accelerators for Increased Beam EnergyStaging laser plasma accelerators is an efficient way ofcompact laser-plasma accelerators to generate particle

Panasenko, Dmitriy

2010-01-01T23:59:59.000Z

465

Electron Beam Charge Diagnostics for Laser Plasma Accelerators  

E-Print Network [OSTI]

the 1989 Particle Accelerator Conference (IEEE, Piscataway,the 1993 Particle Accelerator Conference (IEEE, Piscataway,Diagnostics for Laser Plasma Accelerators K. Nakamura, 1 A.

Nakamura, Kei

2012-01-01T23:59:59.000Z

466

Laser Plasma Particle Accelerators: Large Fields for Smaller Facility Sources  

E-Print Network [OSTI]

essential understanding of accelerator physics to advanceof high- gradient, laser plasma particle accelerators.to conventional particle accelerators, plasmas can sustain

Geddes, Cameron G.R.

2010-01-01T23:59:59.000Z

467

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...

468

Accelerated Evolution of Conserved Noncoding Sequences in the Human Genome  

E-Print Network [OSTI]

associated with CNSs accelerated in chimpanzee. (F)associated with CNSs accelerated in mouse. (G) CNScomponent associations of accelerated CNSs (adjustment for

Prambhakar, Shyam; Noonan, James P.; Paabo, Svante; Rubin, Edward M.

2006-01-01T23:59:59.000Z

469

Effects of an Accelerated Diesel Engine Replacement/Retrofit Program  

E-Print Network [OSTI]

No. 894 Effects of an Accelerated Diesel Engine Replacement/2009 Effects of an Accelerated Diesel Engine Replacement/reductions occurring on an accelerated schedule compared to

Millstein, Dev E.; Harley, Robert A

2009-01-01T23:59:59.000Z

470

Accelerated maximum likelihood parameter estimation for stochastic biochemical systems  

E-Print Network [OSTI]

as: Daigle et al. : Accelerated maximum likelihood parame-Gillespie DT: Approximate accelerated stochastic simulationARTICLE Open Access Accelerated maximum likelihood parameter

Daigle, Bernie J; Roh, Min K; Petzold, Linda R; Niemi, Jarad

2012-01-01T23:59:59.000Z

471

Accelerated New Product Development in Credit Card Industry  

E-Print Network [OSTI]

CALIFORNIA Los Angeles Accelerated New Product DevelopmentABSTRACT OF THE THESIS Accelerated New Product Developmentmodels to provide accelerated new product development

Gupta, Ravi Kumar

2012-01-01T23:59:59.000Z

472

Comments on Backreaction and Cosmic Acceleration  

E-Print Network [OSTI]

In this brief WEB note we comment on recent papers related to our paper "On Acceleration Without Dark Energy".

E. W. Kolb; S. Matarrese; A. Riotto

2005-11-02T23:59:59.000Z

473

Comments on backreaction and cosmic acceleration  

SciTech Connect (OSTI)

In this brief WEB note we comment on recent papers related to our paper ''On Acceleration Without Dark Energy''.

Kolb, Edward W.; /Fermilab /Chicago U., Astron. Astrophys. Ctr. /Chicago U., EFI; Matarrese, Sabinio; /Padua U. /INFN, Padua; Riotto, Antonion; /CERN

2005-11-01T23:59:59.000Z

474

Measurement of valence band structure in arbitrary dielectric films  

SciTech Connect (OSTI)

A new way of measuring the band structure of various dielectric materials using the secondary electron emission from Auger neutralization of ions is introduced. The first example of this measurement scheme is the magnesium oxide (MgO) films with respect to the application of the films in the display industries. The density of state in the valence bands of MgO film and MgO film with a functional layer (FL) deposited over a dielectric surface reveals that the density peak of film with a FL is considerably less than that of film, thereby indicating a better performance of MgO film with functional layer in display devices. The second example of the measurement is the boron-zinc oxide (BZO) films with respect to the application of the films to the development of solar cells. The measurement of density of state in BZO film suggests that a high concentration of boron impurity in BZO films may enhance the transition of electrons and holes through the band gap from the valence to the conduction band in zinc oxide crystals; thereby improving the conductivity of the film. Secondary electron emission by the Auger neutralization of ions is highly instrumental for the determination of the density of states in the valence band of dielectric materials.

Uhm, Han S., E-mail: hsuhm@kw.ac.kr [Department of Electrophysics, Kwangwoon University, 447-1 Wolgye-Dong, Nowon-Gu, Seoul 139-701 (Korea, Republic of); Choi, Eun H. [Department of Electrophysics, Kwangwoon University, 447-1 Wolgye-Dong, Nowon-Gu, Seoul 139-701 (Korea, Republic of)] [Department of Electrophysics, Kwangwoon University, 447-1 Wolgye-Dong, Nowon-Gu, Seoul 139-701 (Korea, Republic of)

2012-10-15T23:59:59.000Z

475

Vapor etching of nuclear tracks in dielectric materials  

DOE Patents [OSTI]

A process involving vapor etching of nuclear tracks in dielectric materials for creating high aspect ratio (i.e., length much greater than diameter), isolated cylindrical holes in dielectric materials that have been exposed to high-energy atomic particles. The process includes cleaning the surface of the tracked material and exposing the cleaned surface to a vapor of a suitable etchant. Independent control of the temperatures of the vapor and the tracked materials provide the means to vary separately the etch rates for the latent track region and the non-tracked material. As a rule, the tracked regions etch at a greater rate than the non-tracked regions. In addition, the vapor-etched holes can be enlarged and smoothed by subsequent dipping in a liquid etchant. The 20-1000 nm diameter holes resulting from the vapor etching process can be useful as molds for electroplating nanometer-sized filaments, etching gate cavities for deposition of nano-cones, developing high-aspect ratio holes in trackable resists, and as filters for a variety of molecular-sized particles in virtually any liquid or gas by selecting the dielectric material that is compatible with the liquid or gas of interest.

Musket, Ronald G. (Danville, CA); Porter, John D. (Berkeley, CA); Yoshiyama, James M. (Fremont, CA); Contolini, Robert J. (Lake Oswego, OR)

2000-01-01T23:59:59.000Z

476

Fundamentals of femtosecond laser ablation of dielectric materials  

SciTech Connect (OSTI)

The modeling of laser-excited dielectric materials requires a detailed description of the electronic excitation. Dielectric materials do not absorb visible light by traditional linear absorption, so the dynamical generation of conduction-band electrons strongly couples to the absorption. The generation of free electrons is initiated by strong-field excitation and followed by multiplication through impact ionization by energetic electrons heated by the laser. The present paper describes an approach to solving the coupled problem of electron excitation and one-dimensional light propagation. The electronic excitation is described in the so-called multiple-rate-equation model, and the light is absorbed by a combination of strong-field excitation and linear absorption by the excited electrons, which are assumed to behave as a free-electron gas described by a Drude model. The model is generic and based on a few key parameters: the wavelength and the pulse duration of the light, and the band gap of the dielectric medium. This allows parametric investigations of ablation phenomena.

Byskov-Nielsen, J.; Le, D. Q. S.; Christensen, M. N.; Balling, P. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Christensen, B. H. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Danish Technological Institute, Kongsvang Alle 29, 8000 Aarhus C (Denmark)

2010-10-08T23:59:59.000Z

477

Voltage regulation in linear induction accelerators  

DOE Patents [OSTI]

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.

Parsons, William M. (Santa Fe, NM)

1992-01-01T23:59:59.000Z

478

RESOLVING BEAM TRANSPORT PROBLEMS IN ELECTROSTATIC ACCELERATORS  

E-Print Network [OSTI]

RESOLVING BEAM TRANSPORT PROBLEMS IN ELECTROSTATIC ACCELERATORS J. D. LARSON (*) Oak Ridge National are frequently encounte- red during the design, operation and upgrading of electrostatic accelerators. Examples are provided of analytic procedures that clarify accelerator ion optics and lead to more effective beam

Boyer, Edmond

479

Voltage regulation in linear induction accelerators  

DOE Patents [OSTI]

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.

Parsons, W.M.

1992-12-29T23:59:59.000Z

480

Accelerating the transformation of power systems  

E-Print Network [OSTI]

Accelerating the transformation of power systems Ancillary Services Peer Exchange with India- to-peer consultation. The 21st Century Power Partnership aims to accelerate the global transformation consultative support Accelerating the transformation of power systems NREL/FS-6A20-61811 · May 2014 15013

Note: This page contains sample records for the topic "dielectric wakefield accelerator" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Technical Report No. 2006510 ACCELERATING MACHINES \\Lambda  

E-Print Network [OSTI]

Technical Report No. 2006­510 ACCELERATING MACHINES \\Lambda Robert Fraser and Selim G. Akl School Abstract This paper presents an overview of accelerating machines. We begin by exploring the history of the accelerating machine model and the potential power that it provides. We look at some of the problems that could

Graham, Nick

482

Accelerated immunosenescence in preindustrial twin mothers  

E-Print Network [OSTI]

Accelerated immunosenescence in preindustrial twin mothers Samuli Helle* , Virpi Lummaa , and Jukka that this tradeoff is a result of reproductive costs accelerating senescence of the immune system, leading to earlier accelerated immunosenescence. immune function cost of reproduction longevity reproductive effort tuberculosis

Lummaa, Virpi

483

HASKELL ARRAYS, ACCELERATED Manuel M. T. Chakravarty  

E-Print Network [OSTI]

HASKELL ARRAYS, ACCELERATED USING GPUS Manuel M. T. Chakravarty University of New South Wales JOINT, memory-access patterns, etc. Portability... Monday, 7 September 2009 #12;OTHER COMPUTE ACCELERATOR ACCELERATOR ARCHITECTURES Goal: portable data parallelism Tesla T10 GPU Monday, 7 September 2009 #12;OTHER

Chakravarty, Manuel

484

Accelerator and Fusion Research Division  

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

Outreach and Diversity Highlights Safety Other Sites and Labs Intramural Outreach and Diversity Highlights Safety Other Sites and Labs Intramural Historical photo of Laboratory founder and cyclotron inventor Ernest Orlando Lawrence at his desk OUR SCIENTIFIC PROGRAMS Accelerator Physics for the ALS Center for Beam Physics LOASIS Laboratory Fusion Science and Ion Beam Technology Superconducting Magnets Free Electron Laser R&D News: AFRD's Jean-Luc Vay and former AFRD scientist Kwang-Je Kim share the US Particle Accelerator School Prize. Andre Anders places two articles among the year's top 30 in the Journal of Applied Physics. AFRD personnel win an R&D 100 in a joint project with industry; the laser at the heart of BELLA sets a world record for laser power. Employees: Safety tips regarding the mountain lion are available. The results from our two most recent Self-Assessment Focus Groups are up, covering emergency preparedness and ergonomics while working offsite.

485

Fermilab's Accelerator and Research Divisions  

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

July 19, 1996 July 19, 1996 Number 14 Fixed-target experimenters not only expect Fermilab's Accelerator and Research Divisions to turn water into wine-they need 10 different vintages. Providing beam to fixed-target experiments presents the challenge of converting high-inten- sity protons into 10 separate beams of varying intensities and particles, from kaons to neu- trinos. The Accelerator Division generates and splits the beam, and then hands the protons off to the Research Division, which converts them into beams of different particles. The process begins with a breath of hydrogen gas. Eventually the hydrogen atoms lose their outer electrons and become a stream of protons-the formation of the beam. Physicists measure two characteristics of the beam: its energy (eV) and its intensity. Intensity

486

Radiological Training for Accelerator Facilities  

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

8-2002 8-2002 May 2002 Change Notice No 1. with Reaffirmation January 2007 DOE HANDBOOK RADIOLOGICAL TRAINING FOR ACCELERATOR FACILITIES U.S. Department of Energy AREA TRNG Washington, D.C. 20585 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. TS This document has been reproduced from the best available copy. Available to DOE and DOE contractors from ES&H Technical Information Services, U.S. Department of Energy, (800) 473-4375, fax: (301) 903-9823. Available to the public from the U.S. Department of Commerce, Technology Administration, National Technical Information Service, Springfield, VA 22161; (703) 605-6000. Change Notice 1. Radiological Safety Training for Accelerator Facilities

487

Particle acceleration in the heliosphere  

Science Journals Connector (OSTI)

The heliosphere is filled with supersonic solar wind that forms shocks wherever it encounters obstacles be they a high speed Coronal Mass Ejection (CME) or regions where fastsolar wind encounters slower-moving solar wind. Energetic particles (> 10s of keV/nuc to 10s of MeV/nuc) associated with these shocks form a test bed for understanding particle acceleration since the shock properties can often be measured and energetic particle composition compared to candidate seed populations. Over the past 15-20 years a wide body of evidence has emerged showing that generally the seed population is the suprathermal ion pool at energies above the bulk solar wind. Understanding the interplanetary suprathermal ion population is therefore a critical step in fully understanding the physical mechanisms that accelerate particles in interplanetary space.

G. M. Mason; M. I. Desai; R. A. Mewaldt; C. M. S. Cohen

2013-01-01T23:59:59.000Z

488

Accelerated leach test development program  

SciTech Connect (OSTI)

In FY 1989, a draft accelerated leach test for solidified waste was written. Combined test conditions that accelerate leaching were validated through experimental and modeling efforts. A computer program was developed that calculates test results and models leaching mechanisms. This program allows the user to determine if diffusion controls leaching and, if this is the case, to make projections of releases. Leaching mechanisms other than diffusion (diffusion plus source term partitioning and solubility limited leaching) are included in the program is indicators of other processes that may control leaching. Leach test data are presented and modeling results are discussed for laboratory scale waste forms composed of portland cement containing sodium sulfate salt, portland cement containing incinerator ash, and vinyl ester-styrene containing sodium sulfate. 16 refs., 38 figs., 5 tabs.

Fuhrmann, M.; Pietrzak, R.F.; Heiser, J.; Franz, E.M.; Colombo, P.

1990-11-01T23:59:59.000Z

489

Cosmic antifriction and accelerated expansion  

Science Journals Connector (OSTI)

We explain an accelerated expansion of the present Universe, suggested from observations of supernovae of type Ia at high redshift, by introducing an antifrictional force that is self-consistently exerted on the particles of the cosmic substratum. Cosmic antifriction, which is intimately related to particle production, is shown to give rise to an effective negative pressure of the cosmic medium. While other explanations for an accelerated expansion (cosmological constant, quintessence) introduce a component of dark energy in addition to standard cold dark matter (CDM) we resort to a phenomenological one-component model of CDM with internal self-interactions. We demonstrate how the dynamics of the cold dark matter model with a cosmological constant may be recovered as a special case of cosmic antifriction. We discuss the connection with two-component models and obtain an attractor behavior for the ratio of the energy densities of both components which provides a possible phenomenological solution to the coincidence problem.

Winfried Zimdahl; Dominik J. Schwarz; Alexander B. Balakin; Diego Pavn

2001-08-03T23:59:59.000Z

490

Electromagnetic induction in accelerated conductors  

Science Journals Connector (OSTI)

Boundary conditions are derived for the interfaces of a conductor moving across an external magnetic field in an ambient medium (vacuum or nonconductor), which consider the emission of electromagnetic waves from the conductor surface as a result of electromagnetic induction. These boundary conditions are applied to the initial-boundary-value problem for the electromagnetic induction in a conducting slab, which is accelerated across a homogeneous magnetic field to a nonrelativistic velocity. Fourier-series solutions are presented for the transient electromagnetic fields in the moving conductor and the discontinuous electromagnetic waves in the ambient space. It is shown that the transient electromagnetic fields inside and outside the conductor are due to two mechanisms, i.e., "velocity induction" (ordinary induction) and "acceleration induction" [dv?(t)dt?0?]. The latter result cannot be explained by means of the Lorentz transformation, which is valid only for constant conductor velocities (inertial frames).

H. E. Wilhelm

1982-06-01T23:59:59.000Z

491

The US muon accelerator program  

E-Print Network [OSTI]

A directed R&D program is presently underway in the U.S. to evaluate the designs and technologies required to provide muon-based high energy physics (HEP) accelerator capabilities. Such capabilities have the potential to provide unique physics reach for the HEP community. An overview of the status of the designs for the neutrino factory and muon collider applications is provided. Recent progress in the technology R&D program is summarized.

Palmer, M A

2015-01-01T23:59:59.000Z

492

Hamiltonian systems in accelerator physics  

SciTech Connect (OSTI)

General features of the design of annular particle accelerators or storage rings are outlined and the Hamiltonian character of individual-ion motion is indicated. Examples of phase plots are presented, for the motion in one spatial degree of freedom, of an ion subject to a periodic nonlinear focusing force. A canonical transformation describing coupled nonlinear motion also is given, and alternative types of graphical display are suggested for the investigation of long-term stability in such cases. 7 figs.

Laslett, L.J.

1985-06-01T23:59:59.000Z

493

Transplanckian collisions at future accelerators  

E-Print Network [OSTI]

Scattering at transplanckian energies offers model independent tests of TeV scale gravity. Black-hole production is one spectacular signal, though a full calculation of the cross section is not yet available. Another signal is given by gravitational elastic scattering, which is maybe less spectacular but which can be nicely computed in the forward region using the eikonal approximation. In this talk I discuss the distinctive signatures of eikonalized scattering at future accelerators.

Riccardo Rattazzi

2002-05-23T23:59:59.000Z

494

Accelerator Research Department BAccelerator Research Department B E163: Laser Acceleration  

E-Print Network [OSTI]

1 Accelerator Research Department BAccelerator Research Department B E163: Laser Acceleration, D. R. Walz Stanford Linear Accelerator Center R. L. Byer, T. Plettner Stanford University * Spokesman. #12;2 Accelerator Research Department B Outline · Introduction ­­ Future requirements for high

Wechsler, Risa H.

495

Acceleration-field calculation for a structure-based laser-driven linear accelerator  

E-Print Network [OSTI]

Acceleration-field calculation for a structure-based laser-driven linear accelerator Y. C. Huanga for publication 16 April 1998 A laser-driven particle accelerator, scaled to optical wavelengths, has a feature size many orders of magnitude smaller than a radio-frequency accelerator. However, similar to a radio

Byer, Robert L.

496

Accelerator and new accelerating schemes B. Heusch (1) and G. Matthieussent (2)  

E-Print Network [OSTI]

1420 Accelerator and new accelerating schemes B. Heusch (1) and G. Matthieussent (2) (1) Centre de and high energy physics, astrophysics and plasma physics had the opportunity to discuss accelerators under con- struction as well as the novel acceleration techniques which have appeared during the past few

Paris-Sud XI, Université de

497

Accelerated_Program_Application_10_31.doc | Revised: 11/4/13 Accelerated Program Application  

E-Print Network [OSTI]

Accelerated_Program_Application_10_31.doc | Revised: 11/4/13 Accelerated Program Application OFFICE://www.grad.usf.edu/ STUDENT AGREEMENT Please initial, indicating agreement: I have reviewed the Accelerated Program Requirements and information (http://www.grad.usf.edu/accelerated.php) I have met with my undergraduate

Meyers, Steven D.

498

US LHC Accelerator Research Program For the BNL-FNAL-LBNL LHC Accelerator Collaboration  

E-Print Network [OSTI]

US LHC Accelerator Research Program Jim Strait For the BNL-FNAL-LBNL LHC Accelerator Collaboration LHC Symposium 3 May 2003 brookhaven - fermilab - berkeley US LHC Accelerator Research Program #12;LHC Symposium - 3 May 03 US LHC Accelerator Research Program - J. Strait 2 Outline Program Goals R&D to Maximize

Large Hadron Collider Program

499

Ozone production by nanoporous dielectric barrier glow discharge in atmospheric pressure air  

SciTech Connect (OSTI)

This study is aimed at demonstrating plasma-chemical ozone production based on low temperature atmospheric pressure glow discharge through nanoporous dielectric barriers. The 20 kHz ac driven discharge is formed in air or oxygen gas flowing in the axial direction of the cylindrical plasma reactor containing four parallel aluminum rods covered with nanoporous alumina films. The discharge utilizing nanoporous dielectric barrier is more uniform and more energy efficient in ozone generation than the discharge through smooth-surface dielectric barriers.

Cho, J. H.; Koo, I. G.; Choi, M. Y.; Lee, W. M. [Department of Chemistry and Division of Energy Systems Research, Ajou University, Suwon 443-749 (Korea, Republic of)

2008-03-10T23:59:59.000Z

500

Advanced Manufacturing Jobs and Innovation Accelerator Challenge |  

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

Technical Assistance » Advanced Manufacturing Jobs and Innovation Technical Assistance » Advanced Manufacturing Jobs and Innovation Accelerator Challenge Advanced Manufacturing Jobs and Innovation Accelerator Challenge October 10, 2013 - 12:01pm Addthis The Advanced Manufacturing Jobs and Innovation Accelerator Challenge (Accelerator) is a multi-agency sponsored competition established to enhance existing regional networks of firms and institutions that accelerate technology-related innovation, business formation, and job creation. Funding provided to these regional networks (also called clusters) help academia, utilities, local governments, and private industry and investors expand partnerships, share strategic information more efficiently, and reduce costs by leveraging existing assets and resources (like physical facilities and equipment).