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1

FNAL-NICADD extruded scintillator  

SciTech Connect

The possibility to produce a scintillator that satisfies the demands of physicists from different science areas has emerged with the installation of an extrusion line at Fermi National Accelerator Laboratory (FNAL). The extruder is the product of the fruitful collaboration between FNAL and Northern Illinois Center for Accelerator and Detector Development (NICADD) at Northern Illinois University (NIU). The results from the light output, light attenuation length and mechanical tolerance indicate that FNAL-NICADD scintillator is of high quality. Improvements in the extrusion die will yield better scintillator profiles and decrease the time needed for initial tuning. This paper will present the characteristics of the FNAL-NICADD scintillator based on the measurements performed. They include the response to MIPs from cosmic rays for individual extruded strips and irradiation studies where extruded samples were irradiated up to 1 Mrad. We will also discuss the results achieved with a new die design. The attractive perspective of using the extruded scintillator with MRS (Metal Resistive Semiconductor) photodetector readout will also be shown.

Beznosko, D.; /Northern Illinois U.; Bross, A.; /Fermilab; Dyshkant, A.; /Northern Illinois U.; Pla-Dalmau, A.; /Fermilab; Rykalin, V.; /Northern Illinois U.

2005-09-01

2

The FNAL injector upgrade  

SciTech Connect

The present FNAL H{sup -} injector has been operational since the 1970s and consists of two magnetron H{sup -} sources and two 750 keV Cockcroft-Walton Accelerators. In the upgrade, both slit-type magnetron sources will be replaced with circular aperture sources, and the Cockcroft-Waltons with a 200 MHz RFQ (radio frequency quadrupole). Operational experience at BNL (Brookhaven National Laboratory) has shown that the upgraded source and RFQ will be more reliable, improve beam quality and require less manpower than the present system. The present FNAL (Fermi National Accelerator Laboratory) injector has been operational since 1978 and has been a reliable source of H{sup -} beams for the Fermilab program. At present there are two Cockcroft-Walton injectors, each with a magnetron H{sup -} source with a slit aperture. With these two sources in operation, the injector has a reliability of better than 97%. However, issues with maintenance, equipment obsolescence, increased beam quality demands and retirement of critical personnel, have made it more difficult for the continued reliable running of the H{sup -} injector. The recent past has also seen an increase in both downtime and source output issues. With these problems coming to the forefront, a new 750 keV injector is being built to replace the present system. The new system will be similar to the one at BNL (Brookhaven National Laboratory) that has a similar magnetron source with a round aperture and a 200MHz RFQ. This combination has been shown to operate extremely reliably.

Tan, C.Y.; Bollinger, D.S.; Duel, K.L.; Lackey, J.R.; Pellico, W.A.; /Fermilab

2011-03-01

3

Fermi National Accelerator Laboratory  

NSDL National Science Digital Library

Fermilab is a national science laboratory of the U.S. Department of Energy and the home of the Tevatron, the world's second-largest particle accelerator. Through this portal, users can learn about Fermilab's experiments, research, projects, and publications. The lab also sponsors an extensive outreach program for K-20 educators and learners, much of which may be accessed online.

Laboratory, Fermi N.

2003-10-10

4

The FNAL Injector Upgrade Status  

SciTech Connect

The new FNAL H{sup -} injector upgrade is currently being tested before installation in the Spring 2012 shutdown of the accelerator complex. This line consists of an H{sup -} source, low energy beam transport (LEBT), 200 MHz RFQ and medium energy beam transport (MEBT). Beam measurements have been performed to validate the design before installation. The results of the beam measurements are presented in this paper.

Tan, C.Y.; Bollinger, D.S.; Duel, K.L.; Karns, P.R.; Lackey, J.R.; Pellico, W.A; Scarpine, V.E.; Tomlin, R.E.; /Fermilab

2012-05-14

5

FNAL system patching design  

Microsoft Academic Search

FNAL has over 5000 PCs running either Linux or Windows software. Protecting these systems efficiently against the latest vulnerabilities that arise has prompted FNAL to take a more central approach to patching systems. Due to different levels of existing support infrastructures, the patching solution for linux systems differs from that of windows systems. In either case, systems are checked for

Jack Schmidt; Al Lilianstrom; Andy Romero; Troy Dawson; Connie Sieh

2004-01-01

6

Ion Source Development For The Proposed FNAL 750 keV Injector Upgrade  

SciTech Connect

Currently there is a Proposed FNAL 750 keV Injector Upgrade for the replacement of the 40 year old Fermi National Laboratory (FNAL) Cockcroft-Walton accelerators with a new ion source and 200 MHz Radio Frequency Quadruple (RFQ). The slit type magnetron being used now will be replaced with a round aperture magnetron similar to the one used at Brookhaven National Lab (BNL). Operational experience from BNL has shown that this type of source is more reliable with a longer lifetime due to better power efficiency. The current source development effort is to produce a reliable source with >60 mA of H{sup -} beam current, 15 Hz rep-rate, 100 {mu}s pulse width, and a duty factor of 0.15%. The source will be based on the BNL design along with development done at FNAL for the High Intensity Neutrino Source (HINS).

Bollinger, D. S. [Fermi National Accelerator Laboratory, Box 500, Batavia, IL 60543 (United States)

2011-09-26

7

FNAL system patching design  

SciTech Connect

FNAL has over 5000 PCs running either Linux or Windows software. Protecting these systems efficiently against the latest vulnerabilities that arise has prompted FNAL to take a more central approach to patching systems. Due to different levels of existing support infrastructures, the patching solution for linux systems differs from that of windows systems. In either case, systems are checked for vulnerabilities by Computer Security using the Nessus tool.

Schmidt, Jack; Lilianstrom, Al; Romero, Andy; Dawson, Troy; Sieh, Connie; /Fermilab

2004-01-01

8

Proposed FNAL 750 KeV Linac Injector Upgrade  

SciTech Connect

The present FNAL linac H{sup -} injector has been operational since 1978 and consists of a magnetron H{sup -} source and a 750 keV Cockcroft-Walton Accelerator. The proposed upgrade to this injector is to replace the present magnetron source having a rectangular aperture with a circular aperture, and to replace the Cockcroft-Walton with a 200 MHz RFQ. Operational experience at other laboratories has shown that the upgraded source and RFQ will be more reliable and require less manpower than the present system.

Tan, C.Y.; Bollinger, D.S.; Schmidt, C.W.; /Fermilab

2009-04-01

9

US Accelerator Contribution to the LHC  

Microsoft Academic Search

In 1998, the United States entered into an agreement with CERN to help build the Large Hadron Collider (LHC), with contributions to the accelerator and to the large HEP detectors. To accomplish this, the US LHC Accelerator Project was formed, encompassing expertise from Brookhaven National Laboratory (BNL), Fermi National Accelerator Laboratory (FNAL) and the Lawrence Berkeley National Laboratory (LBNL). This

Michael J. Lamm

2005-01-01

10

FNAL central email systems  

SciTech Connect

The FNAL Email System is the primary point of entry for email destined for an employee or user at Fermilab. This centrally supported system is designed for reliability and availability. It uses multiple layers of protection to help ensure that: (1) SPAM messages are tagged properly; (2) All mail is inspected for viruses; and (3) Valid mail gets delivered. This system employs numerous redundant subsystems to accomplish these tasks.

Schmidt, Jack; Lilianstrom, Al; Pasetes, Ray; Hill, Kevin; /Fermilab

2004-10-01

11

Vehicle Systems Integration Laboratory Accelerates Powertrain Development  

ScienceCinema

ORNL's Vehicle Systems Integration (VSI) Laboratory accelerates the pace of powertrain development by performing prototype research and characterization of advanced systems and hardware components. The VSI Lab is capable of accommodating a range of platforms from advanced light-duty vehicles to hybridized Class 8 powertrains with the goals of improving overall system efficiency and reducing emissions.

None

2014-06-25

12

Numerical and laboratory simulations of auroral acceleration  

NASA Astrophysics Data System (ADS)

The existence of parallel electric fields is an essential ingredient of auroral physics, leading to the acceleration of particles that give rise to the auroral displays. An auroral flux tube is modelled using electrostatic Vlasov simulations, and the results are compared to simulations of a proposed laboratory device that is meant for studies of the plasma physical processes that occur on auroral field lines. The hot magnetospheric plasma is represented by a gas discharge plasma source in the laboratory device, and the cold plasma mimicking the ionospheric plasma is generated by a Q-machine source. In both systems, double layers form with plasma density gradients concentrated on their high potential sides. The systems differ regarding the properties of ion acoustic waves that are heavily damped in the magnetosphere, where the ion population is hot, but weakly damped in the laboratory, where the discharge ions are cold. Ion waves are excited by the ion beam that is created by acceleration in the double layer in both systems. The efficiency of this beam-plasma interaction depends on the acceleration voltage. For voltages where the interaction is less efficient, the laboratory experiment is more space-like.

Gunell, H.; De Keyser, J.; Mann, I.

2013-10-01

13

Numerical and laboratory simulations of auroral acceleration  

SciTech Connect

The existence of parallel electric fields is an essential ingredient of auroral physics, leading to the acceleration of particles that give rise to the auroral displays. An auroral flux tube is modelled using electrostatic Vlasov simulations, and the results are compared to simulations of a proposed laboratory device that is meant for studies of the plasma physical processes that occur on auroral field lines. The hot magnetospheric plasma is represented by a gas discharge plasma source in the laboratory device, and the cold plasma mimicking the ionospheric plasma is generated by a Q-machine source. In both systems, double layers form with plasma density gradients concentrated on their high potential sides. The systems differ regarding the properties of ion acoustic waves that are heavily damped in the magnetosphere, where the ion population is hot, but weakly damped in the laboratory, where the discharge ions are cold. Ion waves are excited by the ion beam that is created by acceleration in the double layer in both systems. The efficiency of this beam-plasma interaction depends on the acceleration voltage. For voltages where the interaction is less efficient, the laboratory experiment is more space-like.

Gunell, H.; De Keyser, J. [1Belgian Institute for Space Aeronomy, Avenue Circulaire 3, B-1180 Brussels (Belgium)] [1Belgian Institute for Space Aeronomy, Avenue Circulaire 3, B-1180 Brussels (Belgium); Mann, I. [EISCAT Scientific Association, P.O. Box 812, SE-981 28 Kiruna, Sweden and Department of Physics, Umeå University, SE-901 87 Umeå (Sweden)] [EISCAT Scientific Association, P.O. Box 812, SE-981 28 Kiruna, Sweden and Department of Physics, Umeå University, SE-901 87 Umeå (Sweden)

2013-10-15

14

FASTBUS for the particle accelerator laboratories  

NASA Astrophysics Data System (ADS)

The FASTBUS modular high speed data acquisition and control system for high energy physics and other applications was described by Costrell and Dawson at the 1983 Particle Accelerator Conference. Both the specification and the implementation of this interlaboratory development have progressed considerably since that time. Because of its many attractive features, FASTBUS is currently in use in several major nuclear and high energy physics laboratories and is also finding application in other areas.

Dawson, W. K.; Costrell, L.; Ikeda, H.; Ponting, P. J.; Walz, H. V.

1985-05-01

15

US LHC Accelerator Project  

NSDL National Science Digital Library

As the US part of the Large Hadron Collider Program, US LHC "consists of efforts of Brookhaven National Laboratory (BNL), Fermi National Accelerator Laboratory (FNAL), and Lawrence Berkeley National Laboratory (LBNL) to support the construction of the LHC at CERN." This Web site provides visitors with links to each of the three participating laboratories as well as information on recent papers, reports, and other materials related to the project. While a bit dated, there is also a press release covering the production of the highest energy producing superconducting accelerator in the world; it utilizes over 6,000 superconducting magnets.

16

Data acquisition for FNAL E665  

SciTech Connect

The data acquisition system for FNAL E665, an experiment to study deep inelastic muon scattering from nucleons and nuclei, is described. The system is built with the FNAL VAXONLINE and RSX DA building blocks. The structure, capabilities and limitations for data flow, control and monitoring are discussed. 20 refs., 1 fig.

Geesaman, D.F.; Green, M.C.; Kaufman, S.; Tentindo-Repond, S.; Bartlett, J.F.; Melanson, H.L.; Petravick, D.; Michael, D.G.; McLeod, D.; Vidal, M.

1989-01-01

17

Operational experience on the Brookhaven National Laboratory Accelerator Test Facility  

SciTech Connect

Brookhaven National Laboratory Accelerator Test Facility is a laser-electron linear accelerator complex designed to provide high brightness beams for testing of advanced acceleration concepts and high power pulsed photon sources. Results of electron beam parameters attained during the commissioning of the nominally 45 MeV energy machine are presented.

Batchelor, K.; Babzien, M.; Ben-Zvi, I. [and others

1994-09-01

18

US accelerator contribution to the LHC  

SciTech Connect

In 1998, the United States entered into an agreement with CERN to help build the Large Hadron Collider (LHC), with contributions to the accelerator and to the large HEP detectors. To accomplish this, the US LHC Accelerator Project was formed, encompassing expertise from Brookhaven National Laboratory (BNL), Fermi National Accelerator Laboratory (FNAL) and the Lawrence Berkeley National Laboratory (LBNL). This report is a summary of these contributions including the progress towards project completion, as well as a discussion of future plans for continued US participation in the LHC accelerator.

Lamm, Michael J.; /Fermilab

2005-05-01

19

Fermi National Accelerator Laboratory: Acronyms of High-Energy Physics  

NSDL National Science Digital Library

From the Department of Energy's Fermi National Accelerator Laboratory Web site, (last mentioned in the August 2, 2000 Scout Report) comes the handy Acronyms of High-Energy Physics Web site. Organized into four categories including laboratories, accelerators, detectors and experiments, and other institutions, each acronym is followed by a brief description and a link to the site or further information.

1969-12-31

20

Center for accelerator mass spectrometry Lawrence Livermore National Laboratory  

Microsoft Academic Search

The Center for Accelerator Mass Spectrometry (CAMS) at Lawrence Livermore National Laboratory (LLNL) is a multi-disciplinary research organization that conducts both technological and applications research. CAMS operates both an HVEC FN tandem and a NEC Model 5SDH-2 tandem accelerator. Using highly sensitive accelerator-based element and isotope detection methods, staff at CAMS collaborate with a broad scope of external and internal

M. L. Roberts; J. R. Southon; I. D. Proctor

1997-01-01

21

Saskatchewan Accelerator Laboratory annual report 1985.  

National Technical Information Service (NTIS)

Last year was reported on the first year of the upgrading project to add an energy compressor system, a pulse stretcher ring, and a magnetic spectometer to our existing 300 MeV electron linear accelerator. As well as giving a description of the project, t...

H. S. Caplan

1985-01-01

22

High luminosity muon scattering at FNAL  

SciTech Connect

The charge of this group was to evaluate the physics that can be done with a high luminosity {mu} scattering experiment at FNAL using the upgraded Tevatron muon beam, and consider the apparatus required. In this report, the physics that can be accomplished with a high luminosity {mu} scattering experiment is evaluated. The CERN and FNAL {mu} beams are compared in the context of such an experiment. The expected muon flux with the upgraded machine is estimated. Two possible detectors are compared: the air-core toroid experiment proposed by Guyot et al., and an upgraded version of the E665 double-diode apparatus now in place at FNAL. The relative costs of the detectors are considered. A list of detailed questions that need to be answered regarding the double-diode experiment has be compiled. 2 refs., 10 figs., 2 tabs.

Bazizi, K. (California Univ., Riverside, CA (USA)); Conrad, J.; Fang, G. (Harvard Univ., Cambridge, MA (USA)); Erdmann, M. (Freiburg Univ. (Germany, F.R.)); Geesaman, D.; Jackson, H. (Argonne National Lab., IL (USA)); Guyot, C.; Virchaux, M. (CEA Centre d'Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)); Holmgren, H. (Maryland Univ., College Park, MD (USA)); Malensek, A.; Melanson, H.; Morfin

1990-02-01

23

Runtime accelerator configuration tools at Jefferson Laboratory  

SciTech Connect

RF and magnet system configuration and monitoring tools are being implemented at Jefferson Lab to improve system reliability and reduce operating costs. They are prototype components of the Momentum Management System being developed. The RF is of special interest because it affects the momentum and momentum spread of the beam, and because of the immediate financial benefit of managing the klystron DC supply power. The authors describe present and planned monitoring of accelerating system parameters, use of these data, RF system performance calculations, and procedures for magnet configuration for handling beam of any of five beam energies to any of three targets.

Tiefenback, M.G.; Doolittle, L.; Benesch, J.F.

1997-07-01

24

Focusing Solenoid for the Front End of a Linear RF Accelerator.  

National Technical Information Service (NTIS)

A prototype of a superconducting focusing solenoid for use in an RF linac has been built and tested at Fermi National Accelerator Laboratory (FNAL). The solenoid is comprised of the main coil, two bucking coils, two dipole corrector windings, and a low ca...

I. Terechkine J. Tompkins M. Tartaglia T. Page V. V. Kashikhin

2007-01-01

25

Magnet R&D for the US LHC Accelerator Research Program (LARP)  

Microsoft Academic Search

In 2004, the US DOE established the LHC Accelerator Research Program (LARP) with the goal of developing a technology base for future upgrades of the LHC. The focus of the magnet program, which is a collaboration of three US laboratories, BNL, FNAL and LBNL, is on development of high gradient quadrupoles using Nb3Sn superconductor. Other program components address issues regarding

S. A. Gourlay; G. Ambrosio; N. Andreev; M. Anerella; E. Barzi; R. Bossert; S. Caspi; D. R. Dietderich; P. Ferracin; R. Gupta; A. Ghosh; A. R. Hafalia; C. R. Hannaford; M. Harrison; V. S. Kashikhin; V. V. Kashikhin; A. F. Lietzke; S. Mattafirri; A. D. McInturff; F. Nobrega; I. Novitsky; G. L. Sabbi; J. Schmazle; R. Stanek; D. Turrioni; P. Wanderer; R. Yamada; A. V. Zlobin

2006-01-01

26

The target laboratory of the Pelletron Accelerator's facilities  

SciTech Connect

A short report on the activities developed in the Target Laboratory, since 1970, will be presented. Basic target laboratory facilities were provided to produce the necessary nuclear targets as well as the ion beam stripper foils. Vacuum evaporation units, a roller, a press and an analytical balance were installed in the Oscar Sala building. A brief historical report will be presented in commemoration of the 40{sup th} year of the Pelletron Accelerator.

Ueta, Nobuko; Pereira Engel, Wanda Gabriel [Nuclear Physics Department - University of Sao Paulo (Brazil)

2013-05-06

27

Physics for Everyone Lecture Series from Fermi National Accelerator Laboratory (Videos)  

DOE Data Explorer

Physics for Everyoneö is a lecture series organized by Fermilab's Diversity Council. Lectures have been held at various times since 2000 with the goal of sharing Fermilab's science in layman's language with non-technical staff at the laboratory. This goal makes these lectures very accessible and valuable to the public and to students. The videoed presentations are available on the Fermilab website and from the Visual Media Services of the Office of Communications. For titles that are not posted on the Physics for Everyone web page, go to the streaming video archive at http://vms-db-srv.fnal.gov/fmi/xsl/VMS_Site_2/000Search/video/f_streaming.xsl and select the Physics for Everyone series from the search interface. Video titles include: 1) Particle Physics: The World of Matter, Space, and Time, Chris Quigg; 2) Accelerators: Pushing the Limits of Speed, Linda Spentzouris; 3) Introduction to Particle Physics Detectors, Erik Ramberg; 4) The DZero Experiment, Don Lincoln; 5) Relativity, Harrison Prosper ; 6) Pi in the Sky: the SDSS, Chris Stoughton; 7) Discovery at Fermilab, Leon Lederman; 8) Neutrons Against Cancer, Arlene Lennox; 9) The Connections Between Quarks and Cosmos, Michael Turner; 10) The Search for Dark Matter: A Personal Account, Roger Dixon; 11) Magnets for Everyone, Dave Harding; 12) The CDF Experiment, William Wester; 13) Neutrinos and Neutrino Experiments at Fermilab, P. Shanahan; 14) Matter and AntiMatter, Bob Tschirhart; 15) Many Dimensions in Particle Physics, Joe Lykken; 16) Higgs Bosons, Marcela Carena; 17) Future Accelerators, Dave Finley; 18) Physics is FUNdamental, Mary Jo Murphy; 19) Computing at Fermilab from PCS to Petabytes, Dane Skow; 20) What Really Goes on in the Main Control Room, Bob Mau; 21) Exploring the Universe with Neutrinos, John Beacom; 22) E Communication in Physics, Heath O'Connell; 23) A Day in the Life of a Scientist, Bonnie Fleming; 24) Physics without Boundaries, Chris Quigg; 25) The Future of High Energy Physics (as seen from Fermilab), Michael Witherell; 26) Fermilab: How We Got Here and Where We're Going, Herman B. White; 27) What the Cosmos Can Tell Us, Brenna Flaugher; 28) How Particle Physics Can Benefit Society, Elizabeth Clements; 29) The Hunt for the Higgs, Patrick Fox; 30) Fermilab's Future at the Intensity Frontier, Bob Tschirhart; 31) In One Ear and Out the Other: A Neutrino Talk, Dave Schmitz; 32) The Magic of Muons, Chris Polly; 33) At the Energy Frontier: the Tevatron, Rob Roser

28

Reproduction of natural corrosion by accelerated laboratory testing methods  

SciTech Connect

Various laboratory corrosion tests have been developed to study the behavior of glass waste forms under conditions similar to those expected in an engineered repository. The data generated by laboratory experiments are useful for understanding corrosion mechanisms and for developing chemical models to predict the long-term behavior of glass. However, it is challenging to demonstrate that these test methods produce results that can be directly related to projecting the behavior of glass waste forms over time periods of thousands of years. One method to build confidence in the applicability of the test methods is to study the natural processes that have been taking place over very long periods in environments similar to those of the repository. In this paper, we discuss whether accelerated testing methods alter the fundamental mechanisms of glass corrosion by comparing the alteration patterns that occur in naturally altered glasses with those that occur in accelerated laboratory environments. This comparison is done by (1) describing the alteration of glasses reacted in nature over long periods of time and in accelerated laboratory environments and (2) establishing the reaction kinetics of naturally altered glass and laboratory reacted glass waste forms.

Luo, J.S.; Wronkiewicz, D.J.; Mazer, J.J.; Bates, J.K.

1996-05-01

29

The Brookhaven National Laboratory (BNL) Accelerator Test Facility  

SciTech Connect

The design of the Brookhaven National Laboratory Accelerator Test Facility is presented including the design goals and computational results. The heart of the system is a radiofrequency electron gun utilizing a photo-excited metal cathode followed by a conventional electron linac. The Nd:YAG laser used to drive the cathode with 6 ps long pulses can be synchronized to a high peak power CO{sub 2} laser in order to study laser acceleration of electrons. Current operational status of the project will be presented along with early beam tests.

Batchelor, K.

1990-01-01

30

Low Energy Accelerator Laboratory Technical Area 53, Los Alamos National Laboratory. Environmental assessment  

SciTech Connect

This Environmental Assessment (EA) analyzes the potential environmental impacts that would be expected to occur if the Department of Energy (DOE) were to construct and operate a small research and development laboratory building at Technical Area (TA) 53 at the Los Alamos National Laboratory (LANL), Los Alamos, New Mexico. DOE proposes to construct a small building to be called the Low Energy Accelerator Laboratory (LEAL), at a previously cleared, bladed, and leveled quarter-acre site next to other facilities housing linear accelerator research activities at TA-53. Operations proposed for LEAL would consist of bench-scale research, development, and testing of the initial section of linear particle accelerators. This initial section consists of various components that are collectively called an injector system. The anticipated life span of the proposed development program would be about 15 years.

NONE

1995-04-01

31

Recent Developments at the Accelerator Laboratory in Jyväskylä  

NASA Astrophysics Data System (ADS)

Recent developments at the Accelerator Laboratory in Jyväskylä are described. In addition to the existing K = 130 a new cyclotron has been added. It is capable of producing of high current proton and deuteron beams at 30 and 15 MeV correspondingly. It should be fully operational in 2010. A new development in Jyväskylä is the growing commitment to astroparticle physics. Jyväskylä took the main scientific responsibility for a new cosmic-ray experiment EMMA and has joined the LAGUNA project working on the design of the next generation of very large volume detectors for underground observatories.

Trzaska, Wladyslaw Henryk

2010-04-01

32

Recent Developments at the Accelerator Laboratory in Jyvaeskylae  

SciTech Connect

Recent developments at the Accelerator Laboratory in Jyvaeskylae are described. In addition to the existing K = 130 a new cyclotron has been added. It is capable of producing of high current proton and deuteron beams at 30 and 15 MeV correspondingly. It should be fully operational in 2010. A new development in Jyvaeskylae is the growing commitment to astroparticle physics. Jyvaeskylae took the main scientific responsibility for a new cosmic-ray experiment EMMA and has joined the LAGUNA project working on the design of the next generation of very large volume detectors for underground observatories.

Trzaska, Wladyslaw Henryk [Department of Physics, University of Jyvaeskylae, P.O. Box 35 (YFL) FI-40014 (Finland)

2010-04-30

33

The cyclotron laboratory and the RFQ accelerator in Bern  

SciTech Connect

Two proton accelerators have been recently put in operation in Bern: an 18 MeV cyclotron and a 2 MeV RFQ linac. The commercial IBA 18/18 cyclotron, equipped with a specifically conceived 6 m long external beam line ending in a separate bunker, will provide beams for routine 18-F and other PET radioisotope production as well as for novel detector, radiation biophysics, radioprotection, radiochemistry and radiopharmacy developments. The accelerator is embedded into a complex building hosting two physics laboratories and four Good Manufacturing Practice (GMP) laboratories. This project is the result of a successful collaboration between the Inselspital, the University of Bern and private investors, aiming at the constitution of a combined medical and research centre able to provide the most cutting-edge technologies in medical imaging and cancer radiation therapy. The cyclotron is complemented by the RFQ with the primary goals of elemental analysis via Particle Induced Gamma Emission (PIGE), and the detection of potentially dangerous materials with high nitrogen content using the Gamma-Resonant Nuclear Absorption (GRNA) technique. In this context, beam instrumentation devices have been developed, in particular an innovative beam profile monitor based on doped silica fibres and a setup for emittance measurements using the pepper-pot technique. On this basis, the establishment of a proton therapy centre on the campus of the Inselspital is in the phase of advanced study.

Braccini, S.; Ereditato, A.; Kreslo, I.; Nirkko, M.; Weber, M. [Albert Einstein Center for Fundamental Physics, Laboratory for High Energy Physics (LHEP), University of Bern, Sidlerstrasse 5, CH-3012 Bern (Switzerland); Scampoli, P. [Albert Einstein Center for Fundamental Physics, Laboratory for High Energy Physics (LHEP), University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland and Department of Physical Sciences, University Federico II, Via Cintia, I-60126 Napoli (Italy); Bremen, K. von [SWAN Isotopen AG, Inselspital, CH-3010 Bern (Switzerland)

2013-07-18

34

PREFACE: Acceleration and radiation generation in space and laboratory plasmas  

NASA Astrophysics Data System (ADS)

Sixty-six leading researchers from ten nations gathered in the Homeric village of Kardamyli, on the southern coast of mainland Greece, from August 29-September 4, 1993 for the International Workshop on Acceleration and Radiation Generation in Space and Laboratory Plasmas. This Special Issue represents a cross-section of the presentations made at and the research stimulated by that meeting. According to the Iliad, King Agamemnon used Kardamyli as a dowry offering in order to draw a sulking Achilles into the Trojan War. 3000 years later, Kardamyli is no less seductive. Its remoteness and tranquility made it an ideal venue for promoting the free exchange of ideas between various disciplines that do not normally interact. Through invited presen tations, informal poster discussions and working group sessions, the Workshop brought together leaders from the laboratory and space/astrophysics communities working on common problems of acceleration and radiation generation in plasmas. It was clear from the presentation and discussion sessions that there is a great deal of common ground between these disciplines which is not at first obvious due to the differing terminologies and types of observations available to each community. All of the papers in this Special Issue highlight the role collective plasma processes play in accelerating particles or generating radiation. Some are state-of-the-art presentations of the latest research in a single discipline, while others investi gate the applicability of known laboratory mechanisms to explain observations in natural plasmas. Notable among the latter are the papers by Marshall et al. on kHz radiation in the magnetosphere ; Barletta et al. on collective acceleration in solar flares; and by Dendy et al. on ion cyclotron emission. The papers in this Issue are organized as follows: In Section 1 are four general papers by Dawson, Galeev, Bingham et al. and Mon which serves as an introduction to the physical mechanisms of acceleration and radiation generation in plasmas. The next section includes state-of-the-art papers on laboratory accelerators driven by lasers (Nakajima et al., Shukla, Johnson et al.), microwaves (Nishida et al., Bogomolov et al.) and by particle beams (Ogata et al.). Also in this section are theoretical papers presenting new work on synchrotron like oscillations in plasma waves (Fedele) and two types of laboratory radiation sources, FEL's (Marshall et al.) and ionization fronts (Lai et al.), and Frantzeskakis et al. described the Hamiltonian analysis of a slow-wave autonomous cyclotron buncher. Section 3 contains papers on astrophysical plasmas, with the general presentations of Colgate and Krishnan. Kazanas and Krishnan address active galactic nuclei (AGNs). Thielheim discusses general acceleration mech anisms in rotating magnetized systems. Asseo discussed Langmuir solitons in pulsars and Blackman et al. treat magnetic reconnection relativistically. Su et al. analyze the possibility of plasma wave excitation and particle acceleration by neu trinos from supernovae. Dogiel et al. on cosmic ray scattering by MHD fluctuations. The papers in Section 4 treat fusion plasmas (Dendy et al. and Lashmore-Davies et al.). Section 5, space plasmas, includes papers on acceleration processes in the magnetosphere (Anagnostopoulos and Marshall et al.) and the sun (Barletta et al.). It is evident from the Workshop and the papers collected here that this is indeed a rich field of investigations and that both the natural and laboratory plasma communities can benefit from the cross-fertilization of ideas between them. We wish to thank the authors and attendees for their contributions to the success of this workshop, Dr Philip Debenham and Dr David Sutter of the U.S. D.o.E. and Dr Charles Roberson of the U.S. O.N.R. for their financial support (Grants DE-FGO3-93ER40776 and N00014-93-1-0814), and the ECC Twinning Grant SC1*-CT92-0773. We appreciate the considerable local support from Mr Glegles and his staff at the Agricultural Bank of Greece. We thank Mr V. Tataronis, mayor of Kardamyli, and

Bingham, R.; Katsouleas, T.; Dawson, J. M.; Stenflo, L.

1994-01-01

35

Laboratory selection for an accelerated mosquito sexual development rate  

PubMed Central

Background Separating males and females at the early adult stage did not ensure the virginity of females of Anopheles arabiensis (Dongola laboratory strain), whereas two years earlier this method had been successful. In most mosquito species, newly emerged males and females are not able to mate successfully. For anopheline species, a period of 24 h post-emergence is generally required for the completion of sexual maturation, which in males includes a 180° rotation of the genitalia. In this study, the possibility of an unusually shortened sexual maturity period in the laboratory-reared colony was investigated. Methods The effect of two different sex-separation methods on the virginity of females was tested: females separated as pupae or less than 16 h post-emergence were mated with males subjected to various doses of radiation. T-tests were performed to compare the two sex-separation methods. The rate of genitalia rotation was compared for laboratory-reared and wild males collected as pupae in Dongola, Sudan, and analysed by Z-tests. Spermatheca dissections were performed on females mated with laboratory-reared males to determine their insemination status. Results When the sex-separation was performed when adults were less than 16 h post-emergence, expected sterility was never reached for females mated with radio-sterilized males. Expected sterility was accomplished only when sexes were separated at the pupal stage. Observation of genitalia rotation showed that some males from the laboratory strain Dongola were able to successfully mate only 11 h after emergence and 42% of the males had already completed rotation. A small proportion of the same age females were inseminated. Wild males showed a much slower genitalia rotation rate. At 17 h post-emergence, 96% of the laboratory-reared males had completed genitalia rotation whereas none of the wild males had. Conclusion This colony has been cultured in the laboratory for over one hundred generations, and now has accelerated sexual maturation when compared with the wild strain. This outcome demonstrates the kinds of selection that can be expected during insect colonization and maintenance, particularly when generations are non-overlapping and similar-age males must compete for mates.

2011-01-01

36

Improved data acquisition system at the Saskatchewan Accelerator Laboratory  

NASA Astrophysics Data System (ADS)

An improved data acquisition system has been in service at the Saskatchewan accelerator laboratory for the past 14 months. The system has shown itself to be reliable and easy to use having collected over 800 gigabytes of data for a number of experiments. The system is based on a VME front end computer acquiring data from CAMAC and FASTBUS modules and forwarding the data via an Ethernet connection to an acquisition workstation for archiving and on-line analysis. A multiprocessor real-time operating system in the front end computer makes increasing the performance of the system a simple matter of adding an additional processor to the VME chassis. Experiments need only write a high-level description of their experiments which is transformed into a C program for the front end computer by a translation program. Special requirements are met by facilities for direct inclusion of user C or FORTRAN code.

Norum, W. Eric

1994-02-01

37

Center for accelerator mass spectrometry Lawrence Livermore National Laboratory  

SciTech Connect

The Center for Accelerator Mass Spectrometry (CAMS) at Lawrence Livermore National Laboratory (LLNL) is a multi-disciplinary research organization that conducts both technological and applications research. CAMS operates both an HVEC FN tandem and a NEC Model 5SDH-2 tandem accelerator. Using highly sensitive accelerator-based element and isotope detection methods, staff at CAMS collaborate with a broad scope of external and internal researchers to solve problems for LLNL, the University of California, the U.S. Department of Energy, and other academic, government, and industrial laboratories. The HVEC FN tandem is used by the LLNL Accelerator Mass Spectrometry (AMS) group. AMS is a technique that uses isotope ratio mass spectrometry at MeV energies to quantify long lived radioisotopes. For AMS, the FN tandem is operated under a distributed computer control system that makes possible rapid and precise switching between experimental configurations on a daily basis. The accelerator and beam lines are unshielded with radiation protection provided by a computer supervised radiation monitoring system and proximity shielding. With AMS, we routinely measure the isotopes {sup 3} H, {sup 7} Be, {sup 10} Be, {sup 14} C, {sup 26} Al, {sup 36} Cl, {sup 41} Ca, {sup 59} Ni, and {sup 129} I at abundances as low as 1 part in 10{sup 15} . Research programs are as diverse as archaeology, dosimetry of carcinogens and mutagens, oceanic and atmospheric chemistry, paleoclimatology, and detection of signatures of nuclear fuel reprocessing for non-proliferation purposes. During the past year our AMS group has run approximately 20,000 research samples. The NEC Model 5SDH-2 tandem accelerator is used by the Ion Micro Analysis Group (IMAG), a joint collaboration between LLNL and Sandia National Laboratories/California in biological and materials science research. The 1.7 MV accelerator and an Oxford Microbeams Quadrupole Triplet Lens System are used to create a 3 MeV micron scale focused ion beam which is rapidly scanned across research samples. Analysis techniques include Particle Induced X-ray Emission (PIXE) to determine elemental compositions, Scanning Transmission Ion Microtomography (STIM) to determine areal densities, Particle Induced {gamma}-ray Emission (PIGE) to determine isotopic distributions, Elastic Recoil Detection Analysis (ERDA) to determine hydrogen profiles, and Rutherford Back Scattering (RBS). Control of the accelerator, beam transport components, and data acquisition system is through CAMAC using LabVIEW software. Control of the ion source is accomplished using Group 3 hardware. For radiation shielding against x-rays, approximately 20 mm of lead surrounds the accelerator while the direct extraction source is shielded with approximately 3 mm of steel. The rest of the transport system and beam line is unshielded. A unique feature of the system is the detection system consisting of four Ortec IGLET/IGLET-X{trademark} detectors arranged in an array such that a detection solid angle of almost 1 steradian can be achieved. Each detector is capable of detecting approximately 1 keV to 30 keV x-rays with an energy resolution of approximately 160 eV. Current plans at LLNL call for the construction of a new high-resolution high-mass AMS ion source and injection beam line. This injector will be used to develop AMS for long lived isotopes with masses between 79 and 244 AMU. The injector will utilize a Danfysik electrostatic analyzer (900 deflection angle, 750 mm bend radius, 100 mm plate separation, maximum beam rigidity of 75 kV), and an ion source/sample changer identical to our present setup. Because of space constraints, however, the present low-mass AMS injection beam line must be moved/rebuilt before the new high-mass injection beam line can be constructed. We are therefore currently in the process of building a new low-mass AMS ion source and injection beam line. Once this new source/beam line is completed in the next few months, we will begin construction of the high-mass AMS injector. We are also constructing a new high-mass high-e

Roberts, M.L.; Southon, J.R.; Proctor, I.D.

1997-09-01

38

Development of an optical transition radiation detector for profile monitoring of antiproton and proton beams at FNAL  

SciTech Connect

Optical transition radiation (OTR) detectors are being developed at Fermi National Accelerator Laboratory (FNAL) as part of the collider Run II upgrade program and as part of the NuMI primary beam line. These detectors are designed to measure 150 GeV antiprotons as well as 120 GeV proton beams over a large range of intensities. Design and development of an OTR detector capable of measuring beam in both directions down to beam intensities of {approx}5e9 particles for nominal beam sizes are presented. Applications of these OTR detectors as an on-line emittance monitor for both antiproton transfers and reverse-injected protons, as a Tevatron injection profile monitor, and as a high-intensity beam profile monitor for NuMI are discussed. In addition, different types of OTR foils are being evaluated for operation over the intensity range of {approx}5e9 to 5e13 particles per pulse, and these are described.

Scarpine, V.E.; Lindenmeyer, C.W.; Tassotto, G.R.; /Fermilab; Lumpkin, A.H.; /Argonne

2005-05-01

39

Radiation safety systems at Brookhaven National Laboratory's low-energy accelerators  

Microsoft Academic Search

Brookhaven National Laboratory has several low-energy accelerators in use at the present time. I intend to discuss the radiation safety systems installed at five of these accelerators. The accelerators included are a Dynamitron, 3.5 MeV Van de Graaff, 60'' Cyclotron, 41'' Cyclotron and Tandem Van de Graaff facility. All of these accelerators are capable of producing radiation levels in excess

Charles W. Flood; C. W. Jr

1983-01-01

40

The Scanning Electron Microscope As An Accelerator For The Undergraduate Advanced Physics Laboratory  

SciTech Connect

Few universities or colleges have an accelerator for use with advanced physics laboratories, but many of these institutions have a scanning electron microscope (SEM) on site, often in the biology department. As an accelerator for the undergraduate, advanced physics laboratory, the SEM is an excellent substitute for an ion accelerator. Although there are no nuclear physics experiments that can be performed with a typical 30 kV SEM, there is an opportunity for experimental work on accelerator physics, atomic physics, electron-solid interactions, and the basics of modern e-beam lithography.

Peterson, Randolph S. [Department of Physics and Astronomy, University of the South, 735 University Avenue, Sewanee TN 37383 (United States); Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, 50 Vassar Street, Cambridge MA 01239 (United States); Berggren, Karl K.; Mondol, Mark [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, 50 Vassar Street, Cambridge MA 01239 (United States)

2011-06-01

41

Resonance control in SRF cavities at FNAL  

SciTech Connect

The Lorentz force can dynamically detune pulsed Superconducting RF cavities. Considerable additional RF power can be required to maintain the accelerating gradient if no effort is made to compensate for this detuning. Compensation systems using piezo actuators have been used successfully at DESY and elsewhere to control Lorentz Force Detuning (LFD). Recently, Fermilab has developed an adaptive compensation system for cavities in the Horizontal Test Stand, in the SRF Accelerator Test Facility, and for the proposed Project X.

Schappert, W.; Pischalnikov, Y.; /Fermilab; Scorrano, M.; /INFN, Pisa

2011-03-01

42

The Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory  

SciTech Connect

CAMS operates an HVEC FN tandem accelerator for use in both basic research and technology development. The accelerator is operated under a distributed computer control system with sophisticated auto-scaling, beam flat-topping, archiving, and recall capabilities, which makes possible rapid and precise switching between experimental configurations daily. Using the spectrometer, the AMS group can routinely measure the isotopes {sup 3}H, {sup 9}Be, {sup 10}Be, {sup 14}C, {sup 26}Al, {sup 36}Cl, {sup 41}Ca, and {sup 129}I at abundances as low as 1 part in 10{sup 16}.

Roberts, M.L.; Heikkinen, D.W.; Southon, J.R.; Proctor, I.D.

1996-10-01

43

Actinide Measurements by Accelerator Mass Spectrometry at Lawrence Livermore National Laboratory.  

National Technical Information Service (NTIS)

We report on the development of an accelerator mass spectrometry (AMS) system for the measurement of actinides at Lawrence Livermore National Laboratory. This AMS system is centered on a recently completed heavy isotope beam line that was designed particu...

T. A. Brown A. A. Marchetti R. E. Martinelli C. C. Cox J. P. Knezovich

2003-01-01

44

A multibunch plasma wakefield acceleration experiment at the Brookhaven National Laboratory  

Microsoft Academic Search

Plasma-based particle accelerators have made remarkable progress in the recent years. In particular the doubling of the energy of 42 GeV trailing electrons has been demonstrated in a bean-driven plasma wakefield accelerator (PWFA) at the SLAC National Accelerator Laboratory [I. Blumenfeld et al, Nature 445, 741-744 (15 February 2007)]. The next significant step for a PWFA is to demonstrate the

P. Muggli; B. Allen; V. Yakimenko; K. Kusche; M. Babzien; D. Stolyarov

2009-01-01

45

Experience with copper oxide production in antiproton source components at Fermi National Accelerator Laboratory  

Microsoft Academic Search

The Antiproton (Pbar) Source at Fermi National Accelerator Laboratory is a facility comprised of a target station, two rings called the Debuncher and Accumulator and the transport lines between those rings and the remainder of the particle accelerator complex. Water is by far the most common medium for carrying excess heat away from components, primarily electromagnets, in this facility. The

Christine R. Ader; Elvin R. Harms Jr; James P. Morgan

2000-01-01

46

Operational status of the Brookhaven National Laboratory Accelerator Test Facility  

SciTech Connect

Design and operation of a 50 MeV Electron Linear Accelerator utilizing a low emittance ({gamma} {var epsilon} = 5 to 10 mm-mrad) radio frequency gun operating at an output energy of 5 MeV and a charge of 1 nC is described. Design calculations and early radio frequency measurements and operational experience with the electron gun utilizing a dummy copper cathode in place of the proposed photocathode emitter are given. 6 refs., 9 figs., 1 tab.

Batchelor, K.; Ben-Zvi, I.; Chou, T.S.; Fernow, R.C.; Fischer, J.; Gallarado, J.; Kirk, H.G.; Palmer, R.B.; Pellegrini, C.; Sheehan, J.; Srinivasan-Rao, T.; Ulc, S.; Van Steenbergen, A.; Woodle, M.; Biglio, I.; Kurnit, N.; McDonald, K.T. (Brookhaven National Lab., Upton, NY (USA); Los Alamos National Lab., NM (USA); Princeton Univ., NJ (USA). Dept. of Physics)

1989-01-01

47

Upper-division student laboratory experiments with a 2.5 MV Van de Graaff accelerator  

NASA Astrophysics Data System (ADS)

A modern physics laboratory that traditionally emphasized accelerated ion techniques was modified to direct student attention toward the application of these techniques to achieve specific research goals. Students were given an ORTEC surface-barrier detector and access to an accelerator, which they used to determine the elemental identity of materials in the detector and measure their physical properties. Familiarity with the accelerator techniques and the analysis of the data were quickly achieved in the effort to provide more time to meet the research goals of this experiment. The emphasis on the research goals instead of the accelerator-based techniques stimulated a more engaging lab experience. .

Bradbury, D.; Dukes, W.; Gerber, E.; Terry, T.; Peterson, R. S.; Sangsingkeow, P.

2001-07-01

48

A Dust Particle Accelerator for Laboratory Simulations of Cosmic Dust Impacts  

Microsoft Academic Search

Dusty environments in the solar system such as around comets and interstellar dust are the focus of many current investigations. Instruments performing in-situ measurements of dust particles require laboratory testing and calibrating prior to their launch. This laboratory testing is most often done with a high-speed dust particle accelerator. In addition, studies of physical processing of planetary surfaces and spacecraft

H. L. K. Manning

2001-01-01

49

Capture cavity II results at FNAL  

SciTech Connect

As part of the research and development towards the International Linear Collider (ILC), several test facilities have been developed at Fermilab. This paper presents the latest Low Level RF (LLRF) results obtained with Capture Cavity II (CCII) at the ILC Test Accelerator (ILCTA) test facility. The main focus will be on controls and RF operations using the SIMCON based LLRF system developed in DESY [1]. Details about hardware upgrades and future work will be discussed.

Branlard, Julien; Chase, Brian; Cancelo, G.; Carcagno, R.; Edwards, H.; Fliller, R.; Hanna, B.; Harms, Elvan; Hocker, A.; Koeth, T.; Kucera, M.; /Fermilab

2007-06-01

50

Linear Accelerator Laboratory Progress Report: July 1983-October 1985.  

National Technical Information Service (NTIS)

Different experiments presented are Asterix at Lear (CERN), DM2 at DCI (Orsay), NA3 and NA9 at SPS (CERN), NA9 at SPS, Cello at Desy (Hamburg), NA14 and NA31 at SPS, UA2 at SpantipS (CERN), the experiment ''proton meanlife'' at the underground laboratory ...

1987-01-01

51

ACCELERATION OF LOS ALAMOS NATIONAL LABORATORY TRANSURANIC WASTE DISPOSITION  

Microsoft Academic Search

One of Los Alamos National Laboratory's (LANL's) most significant risks is the site's inventory of transuranic waste retrievably stored above and below-ground in Technical Area (TA) 54 Area G, particularly the dispersible high-activity waste stored above-ground in deteriorating facilities. The high activity waste represents approximately 50% (by activity) of the total 292,000 PE-Ci inventory remaining to be disposed. The transuramic

GERALD A

2007-01-01

52

Acceleration of Los Alamos National Laboratory transuranic waste disposition  

Microsoft Academic Search

One of Los Alamos National Laboratory's (LANL's) most significant risks is the site's inventory of transuranic waste retrievably stored above and below-ground in Technical Area (TA) 54 Area G, particularly the dispersible high-activity waste stored above-ground in deteriorating facilities. The high activity waste represents approximately 50% (by activity) of the total 292,000 PE-Ci inventory remaining to be disposed. The transuranic

G. A. OLeary; B. A. Palmer; T. P. Starke; A. K. Phelps

2007-01-01

53

Laboratory selection for an accelerated mosquito sexual development rate  

Microsoft Academic Search

Background  Separating males and females at the early adult stage did not ensure the virginity of females of Anopheles arabiensis (Dongola laboratory strain), whereas two years earlier this method had been successful. In most mosquito species, newly emerged\\u000a males and females are not able to mate successfully. For anopheline species, a period of 24 h post-emergence is generally\\u000a required for the

Clelia F Oliva; Mark Q Benedict; Guy Lempérière; Jérémie Gilles

2011-01-01

54

Control system for BCP processing facility at FNAL  

SciTech Connect

The surface processing is one of the key elements of superconducting RF cavity fabrication. Safety and reliability are the main requirements for the chemical surface treatment facility being developed at FNAL. Accepting the Buffered Chemical Polishing (BCP) as the baseline process, a ''gravity feed and open etching tank'' approach has been chosen at this stage. This choice resulted in the introduction of a control system with a strong automation since the number of elements to be controlled at different steps of the process is rather big. In order to allow for maximum flexibility, two operational modes were defined within the control system: semi-automatic, which requires an operator's decision to move from one stage to another, and manual. This paper describes the main features of the control system for the BCP facility that is under development at FNAL.

Cristian Boffo et al.

2003-09-11

55

Observation of ion acceleration and heating during collisionless magnetic reconnection in a laboratory plasma.  

PubMed

The ion dynamics in a collisionless magnetic reconnection layer are studied in a laboratory plasma. The measured in-plane plasma potential profile, which is established by electrons accelerated around the electron diffusion region, shows a saddle-shaped structure that is wider and deeper towards the outflow direction. This potential structure ballistically accelerates ions near the separatrices toward the outflow direction. Ions are heated as they travel into the high-pressure downstream region. PMID:23745892

Yoo, Jongsoo; Yamada, Masaaki; Ji, Hantao; Myers, Clayton E

2013-05-24

56

Observation of Ion Acceleration and Heating during Collisionless Magnetic Reconnection in a Laboratory Plasma  

SciTech Connect

The ion dynamics in a collisionless magnetic reconnection layer are studied in a laboratory plasma. The measured in-plane plasma potential profile, which is established by electrons accelerated around the electron diffusion region, shows a saddle-shaped structure that is wider and deeper towards the outflow direction. This potential structure ballistically accelerates ions near the separatrices toward the outflow direction. Ions are heated as they travel into the high pressure downstream region.

Jongsoo Yoo, Masaaki Yamada, HantaoJi and Clayton E. Myers

2012-12-10

57

Determination of effective acceleration for use in design at the Lawrence Livermore National Laboratory site  

SciTech Connect

An rms-based effective acceleration study has been conducted for the Lawrence Livermore National Laboratory. The study used real time history records with epicentral distances, magnitudes and site conditions deemed appropriate for the LLNL Livermore site. Only those records having strong motion durations, T{sub D}{prime}, >3.0 seconds, and peak ground acceleration {ge} .4g were selected for determining the effective acceleration hazard curve used in design. These parameters are consistent with LLNL's use of broad-band Newmark-Hall Spectra for design, and the high peak instrumental accelerations corresponding to the return intervals of interest. Study results were used to modify the acceleration hazard curve for facility design/evaluation at LLNL.

Coats, D.W. Jr.

1991-09-01

58

Determination of effective acceleration for use in design at the Lawrence Livermore National Laboratory site  

SciTech Connect

An rms-based effective acceleration study has been conducted for the Lawrence Livermore National Laboratory. The study used real time history records with epicentral distances, magnitudes and site conditions deemed appropriate for the LLNL Livermore site. Only those records having strong motion durations, T{sub D}{prime}, >3.0 seconds, and peak ground acceleration {ge} .4g were selected for determining the effective acceleration hazard curve used in design. These parameters are consistent with LLNL`s use of broad-band Newmark-Hall Spectra for design, and the high peak instrumental accelerations corresponding to the return intervals of interest. Study results were used to modify the acceleration hazard curve for facility design/evaluation at LLNL.

Coats, D.W. Jr.

1991-09-01

59

ACCELERATION OF LOS ALAMOS NATIONAL LABORATORY TRANSURANIC WASTE DISPOSITION  

SciTech Connect

One of Los Alamos National Laboratory's (LANL's) most significant risks is the site's inventory of transuranic waste retrievably stored above and below-ground in Technical Area (TA) 54 Area G, particularly the dispersible high-activity waste stored above-ground in deteriorating facilities. The high activity waste represents approximately 50% (by activity) of the total 292,000 PE-Ci inventory remaining to be disposed. The transuramic waste inventory includes contact-handled and remote-handled waste packaged in drums, boxes, and oversized containers which are retrievably stored both above and below-ground. Although currently managed as transuranic waste, some of the inventory is low-level waste that can be disposed onsite or at approved offsite facilities. Dispositioning the transuranic waste inventory requires retrieval of the containers from above and below-ground storage, examination and repackaging or remediation as necessary, characterization, certification and loading for shipment to the Waste Isolation Pilot Plant in Carlsbad New Mexico, all in accordance with well-defined requirements and controls. Although operations are established to process and characterize the lower-activity contact-handled transuranic waste containers, LAN L does not currently have the capability to repack high activity contact-handled transuranic waste containers (> 56 PE-Ci) or to process oversized containers with activity levels over 0.52 PE-Ci. Operational issues and compliance requirements have resulted in less than optimal processing capabilities for lower activity contact-handled transuranic waste containers, limiting preparation and reducing dependability of shipments to the Waste Isolation Pilot Plant. Since becoming the Los Alamos National Laboratory contract in June 2006, Los Alamos National Security (LANS) L.L.C. has developed a comprehensive, integrated plan to effectively and efficiently disposition the transuranic waste inventory, working in concert with the Department of Energy Los Alamos Site Office, Carlsbad Field Office and the Department of Energy Headquaeters. Rather than simply processing containers as retrieved, the plan places priority on efficient curie disposition, a direct correlation to reducing risk. Key elements of the approch include balancing inventory and operational risks, tailoring methods to meet requirements, optimizing existing facilities, equipment and staff, and incorporating best practices from other Department of Energy sites. With sufficient funding this will enable LANL to ship the above-ground high activity contact-handled transuranic waste offsite by the end of Fiscal Year (FY) 2007 and to disposition the remaining above- and below-ground contact-handled and remote-handled transuranic waste inventory by December 2010. Nearly 70% of the contact-handled transuranic waste containers, including the high activity waste, require processing and repackaging before characterization and certification for shipment to the Waste Isolation Pilot Plant. LANL is employing a balanced risk approach that accomplishes significant long-term risk reduction by accepting short-term increased facility operations risk under well-developed and justified interim controls. Reviews of facility conditions and additional analyses show that the Waste Characterization, Reduction and Repackaging Facility and the Radioassay and Nondestructive Testing Facility are the most appropriate facilities to safetly remediate, repackage, and ship lower activity and the remaining high activity drums. Updated safety documentation supporting limited Hazard Category 2 operations in these facilities has been developed. Once approved, limited-term operations to process the high activity drums can begin in early 2007, building upon the experience base established performing Hazard Category 3 operations processing lower activity waste in these facilities. LANL is also implementing a series of actions to improve and sustain operations for processing contact-handled transuranic waste inventory. Building 412 Decontamination and Volume Facility and Dom

O'LEARY, GERALD A. [Los Alamos National Laboratory

2007-01-04

60

Acceleration of Los Alamos National Laboratory transuranic waste disposition  

SciTech Connect

One of Los Alamos National Laboratory's (LANL's) most significant risks is the site's inventory of transuranic waste retrievably stored above and below-ground in Technical Area (TA) 54 Area G, particularly the dispersible high-activity waste stored above-ground in deteriorating facilities. The high activity waste represents approximately 50% (by activity) of the total 292,000 PE-Ci inventory remaining to be disposed. The transuranic waste inventory includes contact-handled and remote-handled waste packaged in drums, boxes, and oversized containers which are retrievably stored both above and below-ground. Although currently managed as transuranic waste, some of the inventory is low-level waste that can be disposed onsite or at approved offsite facilities. Dis-positioning the transuranic waste inventory requires retrieval of the containers from above and below- ground storage, examination and repackaging or remediation as necessary, characterization, certification and loading for shipment to the Waste Isolation Pilot Plant in Carlsbad, New Mexico, all in accordance with well-defined requirements and controls. Although operations are established to process and characterize the lower-activity contact-handled transuranic waste containers, LANL does not currently have the capability to repack high activity contact-handled transuranic waste containers (> 56 PE-Ci) or to process oversized containers with activity levels over 0.52 PE-Ci. Operational issues and compliance requirements have resulted in less than optimal processing capabilities for lower activity contact-handled transuranic waste containers, limiting preparation and reducing dependability of shipments to the Waste Isolation Pilot Plant. Since becoming the Los Alamos National Laboratory contractor in June 2006, Los Alamos National Security (LANS) L.L.C. has developed a comprehensive, integrated plan to effectively and efficiently disposition the transuranic waste inventory, working in concert with the Department of Energy Los Alamos Site Office, Carlsbad Field Office and the Department of Energy Headquarters. Rather than simply processing containers as retrieved, the plan places priority on efficient curie disposition, a direct correlation to reducing risk. Key elements of the approach include balancing inventory and operational risks, tailoring methods to meet requirements, optimizing existing facilities, equipment and staff, and incorporating best practices from other Department of Energy sites. With sufficient funding this will enable LANL to ship the above-ground high activity contact-handled transuranic waste offsite by the end of Fiscal Year (FY) 2007 and to disposition the remaining above- and below-ground contact-handled and remote-handled transuranic waste inventory by December 2010. Nearly 70% of the contact-handled transuranic waste containers, including the high activity waste, require processing and repackaging before characterization and certification for shipment to the Waste Isolation Pilot Plant. LANL is employing a balanced risk approach that accomplishes significant long-term risk reduction by accepting short-term increased facility operations risk under well-developed and justified interim controls. Reviews of facility conditions and additional analyses show that the Waste Characterization, Reduction and Repackaging Facility and the Radioassay and Nondestructive Testing Facility are the most appropriate facilities to safely remediate, repackage, and ship lower activity and the remaining high activity drums. Updated safety documentation supporting limited Hazard Category 2 operations in these facilities has been developed. Once approved, limited-term operations to process the high activity drums can begin in early 2007, building upon the experience base established performing Hazard Category 3 operations processing lower activity waste in these facilities. LANL is also implementing a series of actions to improve and sustain operations for processing contact-handled transuranic waste inventory. Building 412 Decontamination and Volume Reduction Fa

O'Leary, G.A.; Palmer, B.A.; Starke, T.P.; Phelps, A.K. [Los Alamos National Security, L.L.C., Los Alamos National Laboratory, Los Alamos, NM (United States)

2007-07-01

61

Challenges for forecasting based on accelerating rates of earthquakes at volcanoes and laboratory analogues  

Microsoft Academic Search

'Mean-field' models have been proposed as falsifiable hypotheses for the acceleration in earthquake rate and other geophysical parameters prior to laboratory rock failure and volcanic eruptions. Importantly, such models may permit forecasting failure or eruption time. However, in existing retrospective analyses it is common to find examples of inappropriate techniques for fitting these models to data. Here we test the

Andrew F. Bell; John Greenhough; Michael J. Heap; Ian G. Main

2011-01-01

62

Operation of the DC current transformer intensity monitors at FNAL during run II  

SciTech Connect

Circulating beam intensity measurements at FNAL are provided by five DC current transformers (DCCT), one per machine. With the exception of the DCCT in the Recycler, all DCCT systems were designed and built at FNAL. This paper presents an overview of both DCCT systems, including the sensor, the electronics, and the front-end instrumentation software, as well as their performance during Run II.

Crisp, J.; Fellenz, B.; Heikkinen, D.; Ibrahim, M.A.; Meyer, T.; Vogel, G.; /Fermilab

2012-01-01

63

Surveying the monument system at Lawrence Berkeley Laboratory`s Advanced Light Source accelerator  

SciTech Connect

Particle accelerators with demanding alignment requirements face a need for periodic re-surveying of their reference monument systems. At the ALS, significant foundation settling and the necessary relocation of some floor monuments mean that the entire system of over 100 monuments must be re-surveyed to an accuracy of 100 microns at two year intervals. Last Fall, the monument survey was conducted entirely by the in-house Survey and Alignment crew using a simplified instrument mounting system and an inexpensive commercial software package. Precision levels, plummets, theodolites, and an electronic distance measuring system were used with the innovative ``Monopod`` instrument mounting system in a cost effective approach to this critical task.

Thur, W.; Lauritzen, T.

1995-04-01

64

Beam dynamics studies of the 8 GeV Linac at FNAL  

SciTech Connect

The proposed 8-GeV proton driver (PD) linac at FNAL includes a front end up to {approx}420 MeV operating at 325 MHz and a high energy section at 1300 MHz. A normal conducting RFQ and short CH type resonators are being developed for the initial acceleration of the H-minus or proton beam up to 10 MeV. From 10 MeV to {approx}420 MeV, the voltage gain is provided by superconducting (SC) spoke-loaded cavities. In the high-energy section, the acceleration will be provided by the International Linear Collider (ILC)-style SC elliptical cell cavities. To employ existing, readily available klystrons, an RF power fan out from high-power klystrons to multiple cavities is being developed. The beam dynamics simulation code TRACK, available in both serial and parallel versions, has been updated to include all known H-minus stripping mechanisms to predict the exact location of beam losses. An iterative simulation procedure is being developed to interact with a transient beam loading model taking into account RF feedback and feedforward systems.

Ostroumov, P.N.; Mustapha, B.; /Argonne; Carneiro, J.-P.; /Fermilab

2008-11-01

65

Testing of large area drift chambers at the Saskatchewan Accelerator Laboratory for High Energy Astrophysics  

Microsoft Academic Search

Large area (0.5 m×0.5 m) drift chambers developed for the imaging system for the Advanced Gamma Ray Astronomy Telescope Experiment (AGATE), sensitive in the energy range 20 MeV to 100 GeV, have been tested at the Saskatchewan Accelerator Laboratory (SAL) in March 1995. Testing was performed with the instrument configured in 3 different angles relative to the incident photon beam

R. Cuddapah; D. L. Bertsch; J. R. Catelli; B. L. Dingus; J. A. Esposito; C. E. Fichtel; R. C. Hartman; S. D. Hunter; R. Mukherjee; D. J. Thompson; J. M. Vogt

1995-01-01

66

Plasma-Surface Interaction Research At The Cambridge Laboratory Of Accelerator Studies Of Surfaces  

Microsoft Academic Search

The material requirements for plasma-facing components in a nuclear fusion reactor are some of the strictest and most challenging facing us today. These materials are simultaneously exposed to extreme heat loads (20 MW\\/m2 steady-state, 1 GW\\/m2 in millisecond transients) and particle fluxes (>1024 m-2 s-1) while also undergoing high neutron irradiation (1018 neutrons\\/m2 s). At the Cambridge Laboratory of Accelerator

G. M. Wright; H. S. Barnard; Z. S. Hartwig; P. W. Stahle; R. M. Sullivan; K. B. Woller; D. G. Whyte

2011-01-01

67

Plasma-Surface Interaction Research At The Cambridge Laboratory Of Accelerator Studies Of Surfaces  

Microsoft Academic Search

The material requirements for plasma-facing components in a nuclear fusion reactor are some of the strictest and most challenging facing us today. These materials are simultaneously exposed to extreme heat loads (20 MW?m2 steady-state, 1 GW?m2 in millisecond transients) and particle fluxes (>1024 m?2 s?1) while also undergoing high neutron irradiation (1018 neutrons?m2 s). At the Cambridge Laboratory of Accelerator

G. M. Wright; H. S. Barnard; Z. S. Hartwig; P. W. Stahle; R. M. Sullivan; K. B. Woller; D. G. Whyte

2011-01-01

68

Linking accelerated laboratory and outdoor exposure results for PV polymeric materials: a mechanistic study of EVA  

NASA Astrophysics Data System (ADS)

Linking accelerated laboratory test to field performance for predicting the service life of polymeric materials are being investigated at NIST using the reliability-based methodology. Based on this methodology, a successful linkage between the laboratory and field exposure data for a model polymeric material has been made. Recently, this methodology, for the first time, was introduced to the lifetime assessment of PV polymeric materials. In this paper, a mechanistic study of the degradation of three unstabilized model ethylene vinyl acetate (EVA) systems---uncured EVA, cured EVA and laminated EVA---was carried out under accelerated laboratory exposure and outdoor exposure. The NIST SPHERE (Simulated Photodegradation via High Energy Radiant Exposure) was used for the accelerated laboratory tests, and the outdoor exposure was conducted in Gaithersburg, Maryland. Simultaneous multiple stresses, including temperature, relative humidity and UV radiation, were applied individually or in combination during SPHERE exposure. The effects of the environmental factors on the main degradation mechanisms of different EVA systems were investigated. The results showed that the UV radiation was the most important factor for the degradation of EVA and a synergistic effect occurred between UV radiation and relative humidity. A slower degradation rate was observed for the laminated system as a result of limited diffusion of O2 and H2O into EVA. It was also found that the substantial chemical changes of the uncured EVA system did not yield yellowing, which was dramatically different from the peroxide cured EVA system. Additionally, the chemical degradation modes of the three EVA systems exposed outdoors appeared to be similar to those exposed to the SPHERE. The implication of this work to the current test standards was discussed.

Gu, Xiaohong; Pang, Yongyan; Lin, Chiao-Chi; Liu, Kaipeng; Nguyen, Tinh; Chin, Jaonnie W.

2013-09-01

69

Challenges for forecasting based on accelerating rates of earthquakes at volcanoes and laboratory analogues  

NASA Astrophysics Data System (ADS)

'Mean-field' models have been proposed as falsifiable hypotheses for the acceleration in earthquake rate and other geophysical parameters prior to laboratory rock failure and volcanic eruptions. Importantly, such models may permit forecasting failure or eruption time. However, in existing retrospective analyses it is common to find examples of inappropriate techniques for fitting these models to data. Here we test the two main competing hypotheses—exponential and power-law acceleration—using maximum likelihood techniques and an information criterion for model choice, based on a Poisson process with variable rate. For examples from the laboratory and Mt Etna, the power law is clearly the best model, both in terms of the fit and the resulting error structure, which is consistent with the Poisson approximation. For examples from Kilauea and Mauna Loa the results are less clear-cut and the confidence interval underestimates the number of outliers. Deviations from the models most likely reflect local interactions and/or non-stationary loading processes not captured by the mean-field approach. In addition, we use simulations to demonstrate an inherent problem with model preference, in that a power-law model will only be preferred if failure or eruption occurs close to the singularity. Although mean-field models may well provide valuable insight into the physical process responsible for precursory accelerations in earthquake rate, our findings highlight major difficulties that must be overcome to use such models for forecasting.

Bell, Andrew F.; Greenhough, John; Heap, Michael J.; Main, Ian G.

2011-05-01

70

Evolution of a Pump and Treat Remediation Systems at the SLAC National Accelerator Laboratory, Menlo Park, California.  

National Technical Information Service (NTIS)

Pump and treat operations have been conducted over the past ten years at the Former Solvent Underground Storage Tank (FSUST) Area, located at the SLAC National Accelerator Laboratory (SLAC) located in Menlo Park, California. Soil and groundwater at the FS...

A. Ng C. D. Umezaki D. P. G. Harbaugh M. Moes

2013-01-01

71

An improved 8 GeV beam transport system for the Fermi National Accelerator Laboratory  

SciTech Connect

A new 8 GeV beam transport system between the Booster and Main Ring synchrotrons at the Fermi National Accelerator Laboratory is presented. The system was developed in an effort to improve the transverse phase space area occupied by the proton beam upon injection into the Main Ring accelerator. Problems with the original system are described and general methods of beamline design are formulated. Errors in the transverse properties of a beamline at the injection point of the second synchrotron and their effects on the region in transverse phase space occupied by a beam of particles are discussed. Results from the commissioning phase of the project are presented as well as measurements of the degree of phase space dilution generated by the transfer of 8 GeV protons from the Booster synchrotron to the Main Ring synchrotron.

Syphers, M.J.

1987-06-01

72

Installation of a cw radiofrequency quadrupole accelerator at Los Alamos National Laboratory  

SciTech Connect

Chalk River Laboratories (CRL) has had a long history of cw proton beam development for production of intense neutron sources and fissile fuel breeders. In 1986 CRL and Los Alamos National Laboratory (LANL) entered into a collaborative effort to establish a base technologies program for the development of a cw radiofrequency quadrupole (RFQ). The initial cw RFQ design had 50-keV proton injection energy with 600-keV output energy. The 75-mA design current at 600-keV beam energy was obtained in 1990. Subsequently, the RFQ output energy was increased to 1250 keV by replacing the RFQ vanes, still maintaining the 75-m A design current. A new 250-kW cw klystrode rf power source at 267-MHz was installed at CRL. By April of 1993, 55-mA proton beams had been accelerated to 1250 keV. Concurrent developments were taking place on proton source development and on 50-keV low-energy beam transport (LEBT) systems. Development of a dc, high-proton fraction ({ge} 70%) microwave ion source led to utilization of a single-solenoid RFQ direct injection scheme. It was decided to continue this cw RFQ demonstration project at Los Alamos when the CRL project was terminated in April 1993. The LANL goals are to find the current limit of the 1250-keV RFQ, better understand the beam transport properties through the single-solenoid focusing LEBT, continue the application of the cw klystrode tube technology to accelerators, and develop a two-solenoid LEBT which could be the front end of an Accelerator-Driven Transmutation Technologies (ADTT) linear accelerator.

Schneider, J.D.; Bolme, J.; Brown, V. [and others

1994-09-01

73

Accelerators  

NSDL National Science Digital Library

What is the purpose of particle accelerators? On this web page, part of a particle physics tutorial, students read that accelerators solve two problems. The accelerators provide an increase in momentum to produce particles of small wavelength, and the fast-moving particles can create new particles when smashed together. A photograph of the inside of a particle accelerator is provided. Copyright 2005 Eisenhower National Clearinghouse

Group, Lawrence B.

2002-01-01

74

The UNAM sets up the first Laboratory on Accelerator Mass Spectrometry (LEMA) in Mexico  

NASA Astrophysics Data System (ADS)

A new Accelerator Mass Spectrometry system is being installed at the Institute of Physics of the National Autonomous University of Mexico (IFUNAM) with support of CONACYT and UNAM. The AMS system is based on a tandetron accelerator of 1MV purchased from the High Voltage Engineering Europe B.V., Amersfoort, the Netherlands. Mass spectrometry experiments will be conducted at the AMS laboratory (LEMA), for analysis of 14 C and other isotopes as the 10Be, 26Al, 129I and Pu. This is a highly sensitive technique that allows to measure concentrations up to one part in 1015 from different nuclei. LEMA is the first laboratory in Mexico of its kind and the second in Latin America, after Brazil. The first research line of LEMA is to apply AMS for dating with 14C. Once the dating methodologies will be implemented, we will incorporate the analysis of other radioisotopes in research projects in different areas such as the Geophysical and Environmental sciences. In this presentation, the AMS system as well as details on the sample preparation will be described. Also, results from installation and acceptance tests will be presented.

Solís, C.; Chávez, E.; Ortíz, M. E.; Andrade, E.

2013-05-01

75

On the effect of accelerated winds on the wave growth through detailed laboratory measurements.  

NASA Astrophysics Data System (ADS)

The possible influence of accelerated winds on air-water momentum fluxes is being studied through detailed laboratory measurements in a large wind-wave flume. Wind stress over the water surface, waves and surface drift are measured in the 40m long wind-wave tank at IRPHE, Marseille. While momentum fluxes are estimated directly through the eddy correlation method in a station about the middle of the tank, they provide information corresponding to rather short non-dimensional fetch not previously reported. Wave evolution along the tank is determined through a series of wave gauges, and the wind-induced surface drift is obtained at one of the first measuring stations at the beginning of the tank. At each experimental run very low wind was on (about 1m/s) for a certain period and suddenly it was constantly accelerated to reach about 13 m/s (as well as 8 and 5 m/s during different runs) in about 15 sec to as long as 600 sec. The wind was kept constant at that high speed for 2 to 10 min, and then suddenly and constantly decelerate to 0. Data from the constant high winds provided us with reference equilibrium conditions for at least 3 different wind speed. We, nevertheless, focus in the recordings while wind was being constantly accelerated expecting some contribution to the understanding of gustiness, the implied wind wave growth and the onset of surface drift. Wind-wave growth is observed to lag behind the wind stress signal, and furthermore, a two regime wind stress is noticed, apparently well correlated with a) the incipient growth and appearance of the first waves and b) the arrival of waves from the up-wind section of the tank. Results of non-dimensional wave energy as a function of non-dimensional fetch represent an extension of at least 2 decades shorter non-dimensional fetch to the wave growth curves typically found in the literature. The linear tendency of wave growth compares very well only when wind is reaching its maximum, while during the accelerated wind period a lower non-dimensional wave energy is found. Details on the onset of wind-induced surface drift at the beginning of the tank will be addressed within the context of accelerated wind conditions. This work represents a RugDiSMar Project (CONACYT 155793) contribution. The support from ANUIES-ECOS M09-U01 project, CONACYT-187112 Estancia Sabática, and Institute Carnot, is greatly acknowledged.

Ocampo-Torres, Francisco J.; Branger, Hubert; Osuna, Pedro; Hernández, Aldo

2013-04-01

76

Proposed low-level radioactive waste handling building at Fermi National Accelerator Laboratory, Batavia, Illinois  

SciTech Connect

The US Department of Energy (DOE) has prepared an Environmental Assessment (EA), evaluating the impacts associated with the proposed Low-Level Radioactive Waste Building at the Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois. As a result of the high energy physics program at Fermilab, small quantities of low-level radioactive wastes are generated. These wastes are collected, sorted and packaged for shipment to an off-site disposal facility in Hanford, Washington. The proposed project includes the construction of a new building to house, all low-level radioactive waste handling operations. The building would provide workspace for five full-time workers. The proposed project would improve the efficiency and safety of the low-level radioactive waste handling at Fermilab by upgrading equipment and consolidating operations into one facility.

NONE

1995-06-01

77

Proposed Casey`s Pond Improvement Project, Fermi National Accelerator Laboratory  

SciTech Connect

The U.S. Department of Energy (DOE) has prepared an Environmental Assessment (EA), evaluating the impacts associated with the proposed Casey`s Pond Improvement Project at the Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois. The improvement project would maximize the efficiency of the Fermilab Industrial Cooling Water (ICW) distribution system, which removes (via evaporation) the thermal load from experimental and other support equipment supporting the high energy physics program at Fermilab. The project would eliminate the risk of overheating during fixed target experiments, ensure that the Illinois Water Quality Standards are consistently achieved and provide needed additional water storage for fire protection. Based on the analysis in the EA, the DOE has determined that the proposed action does not constitute a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, the preparation of an Environmental Impact Statement is not required.

NONE

1995-05-01

78

Inter-laboratory comparison of UV-light sources for accelerated durability testing of PV modules  

NASA Astrophysics Data System (ADS)

Accelerated testing of the durability of materials exposed to natural weathering requires testing of the UV stability, especially for polymeric materials. The type approval testing of PV-modules according to the standards IEC 61215 and IEC 61646 includes a so-called UV-preconditioning test with a total UV dose of 15 kWh/m2. Fraunhofer ISE performed an Inter-laboratory comparison of UV-light sources in accredited test labs and in test centres of major PV module manufacturers. One topic was the spectral measurement of the used UV sources. Another main issue was the comparison of the integral measurements by the sensors used for control of the tests. Errors up to 120% were found.

Philipp, Daniel; Weiss, Karl-Anders; Koehl, Michael

2011-09-01

79

A new LabVIEW-based control system for the Naval Research Laboratory Trace Element Accelerator Mass Spectrometer  

NASA Astrophysics Data System (ADS)

A new LabVIEW-based control system for the existing tandem accelerator and new AMS components has been implemented at the Trace Element Accelerator Mass Spectrometry (TEAMS) facility at the Naval Research Laboratory. Through the use of Device Interfaces (DIs) distributed along a fiber optic network, virtually every component of the accelerator system can be controlled from any networked computer terminal as well as remotely via modem or the internet. This paper discusses the LabVIEW-based control software, including remote operation, automatic calculation of ion optical component parameters, beam optimization, and data logging and retrieval.

Deturck, T. M.; Treacy, D. J.; Knies, D. L.; Grabowski, K. S.; Knoll, C.; Kennedy, C. A.; Hubler, G. K.

1999-06-01

80

Application of the National Ignition Facility distinguishable-from-background program to accelerator facilities at Lawrence Livermore National Laboratory.  

PubMed

Lawrence Livermore National Laboratory must control potentially activated materials and equipment in accordance with U.S. Department of Energy (DOE) Order 458.1, Radiation Protection of the Public and the Environment, which requires DOE approval of the process used to release volumetrically contaminated personal property and establishes a dose constraint of 10 µSv y(-1) (1 mrem y(-1)) for clearance of such property. The National Ignition Facility at Lawrence Livermore National Laboratory developed a technical basis document and protocol for determining the radiological status of property that is potentially activated from exposure to neutron radiation produced via fusion of tritium and deuterium. The technical basis included assessment of the neutron energy, the type of materials potentially exposed and the likely activation products, and the sensitivity of radiation detectors used to survey the property. This paper evaluates the National Ignition Facility technical basis document for applicability to the release of property from Lawrence Livermore National Laboratory's various accelerator facilities considering the different types of particles accelerated, radiations produced, and resultant activation products. Extensive process knowledge regarding the accelerators' operations, accompanied by years of routine surveys, provides an excellent characterization of these facilities. Activation studies conducted at the Stanford Linear Accelerator and the High Energy Accelerator Research Organization in Japan corroborate that the long-lived radionuclides produced at accelerator facilities are of the same variety produced at the National Ignition Facility. Consequently, Lawrence Livermore National Laboratory concludes that the release protocol developed for the National Ignition Facility can be used appropriately at all its accelerator facilities. PMID:23629069

Packard, Eric D; Mac Kenzie, Carolyn

2013-06-01

81

Radio frequency systems for present and future accelerators  

SciTech Connect

Rf systems are described for the FNAL Main Ring and Tevatron Ring, CERN SPS and LEP, and HERA proton acceleration system, CERN PS e/sup +/e/sup minus/ acceleration system, and CERN EPA monochromatic cavity. Low impedance rf systems in CERN ISR, the Brookhaven CBA, and SSC are also discussed.

Raka, E.C.

1987-01-01

82

Type A Accident Investigation of the June 21, 2001 Drilling Rig Operator Injury at the Fermi National Accelerator Laboratory.  

National Technical Information Service (NTIS)

On June 21, 2001, at approximately 9:40 A.M., a construction sub-tier contractor employee (the 'Operator') at the Fermi National Accelerator Laboratory (Fermilab) received serious head injuries requiring hospitalization when he was struck by part of the d...

2001-01-01

83

Acceleration \\  

Microsoft Academic Search

The paper proposes a digital compensation by imposing real-time compensation voltage to Vin Pin of VCOXCO while device vibrating. The embedded digital compensating circuit includes a MEMS three-axes acceleration sensor, a FPGA and a D\\/A converter. G-sensitivity vector can be computed based on the MEMS sensor. A proportion digital compensation model is built to generate voltage which can compensate frequency

QingXiao Shan; Yang Jun; JianYun Chen; Tang Qian; LongZhe Ji

2011-01-01

84

Laboratory laser acceleration and high energy astrophysics: {gamma}-ray bursts and cosmic rays  

SciTech Connect

Recent experimental progress in laser acceleration of charged particles (electrons) and its associated processes has shown that intense electromagnetic pulses can promptly accelerate charged particles to high energies and that their energy spectrum is quite hard. On the other hand some of the high energy astrophysical phenomena such as extremely high energy cosmic rays and energetic components of {gamma}-ray bursts cry for new physical mechanisms for promptly accelerating particles to high energies. The authors suggest that the basic physics involved in laser acceleration experiments sheds light on some of the underlying mechanisms and their energy spectral characteristics of the promptly accelerated particles in these high energy astrophysical phenomena.

Tajima, T. [Univ. of Texas, Austin, TX (United States); Takahashi, Y. [Univ. of Alabama, Huntsville, AL (United States). Dept. of Physics

1998-08-20

85

Autopsy results of failed lithium collection lenses at the FNAL antiproton source  

Microsoft Academic Search

A lithium lens focusing device is used at the FNAL antiproton source to collect antiprotons immediately downstream of the production target. Recently developed methods of removing lithium from old collection lens devices have enabled the dissection and autopsy of several failed lenses. Examination reveals longitudinal fatigue cracks in the titanium alloy (6Al-4V) cooling jackets. A finite element analysis to estimate

P. Hurh; A. Leveling

2003-01-01

86

Earthquake Dynamics in Laboratory Model and Simulation - Accelerated Creep as Precursor of Instabilities  

NASA Astrophysics Data System (ADS)

Shallow earthquakes can be considered as a result of tribological instabilities, so called stick-slip behaviour [1,2], meaning that sudden slip occurs at already existing rupture zones. From a contact mechanics point of view it is clear, that no motion can arise completely sudden, the material will always creep in an existing contact in the load direction before breaking loose. If there is a measureable creep before the instability, this could serve as a precursor. To examine this theory in detail, we built up an elementary laboratory model with pronounced stick-slip behaviour. Different material pairings, such as steel-steel, steel-glass and marble-granite, were analysed at different driving force rates. The displacement was measured with a resolution of 8 nm. We were able to show that a measureable accelerated creep precedes the instability. Near the instability, this creep is sufficiently regular to serve as a basis for a highly accurate prediction of the onset of macroscopic slip [3]. In our model a prediction is possible within the last few percents of the preceding stick time. We are hopeful to extend this period. Furthermore, we showed that the slow creep as well as the fast slip can be described very well by the Dieterich-Ruina-friction law, if we include the contribution of local contact rigidity. The simulation meets the experimental curves over five orders of magnitude. This friction law was originally formulated for rocks [4,5] and takes into account the dependency of the coefficient of friction on the sliding velocity and on the contact history. The simulations using the Dieterich-Ruina-friction law back up the observation of a universal behaviour of the creep's acceleration. We are working on several extensions of our model to more dimensions in order to move closer towards representing a full three-dimensional continuum. The first step will be an extension to two degrees of freedom to analyse the interdependencies of the instabilities. We also plan to install a larger system which is capable of performing events of different spatial extent and magnitude. [1] Stick-Slip as a Mechanism for Earthquakes. Brace, W.F. und Byerlee, J.D. 1966, Science, Bd. 153, S. 990-992. [2] Detailed Studies of Frictional Sliding of Granite and Implications for the Earthquake Mechanism. Scholz, C. H., Molnar, P. und Johnson, T. 32, 1972, Journal of Geophysical Research, Bd. 77, S. 6392-6409. [3] Accelerated Creep as a Precursor of Friction Instability and Earthquake Prediction. Popov, V. L., et al. 2010, Physical Mesomechanics, Bd. 13, S. 283-291. [4] Modeling of Rock Friction, Part 1: Experimental Results and Constitutive Equations. Dieterich, J.H. B5, 1979, Journal of Geophysical Research, Bd. 84, S. 2161-2168. [5] State Instability and State Variable Friction Law. Ruina, A. B12, 1983, Journal of Geophysical Research, Bd. 88, S. 10359-10370.

Grzemba, B.; Popov, V. L.; Starcevic, J.; Popov, M.

2012-04-01

87

Accelerating Moment Release of Acoustic Emission During Rock Deformation in the Laboratory  

NASA Astrophysics Data System (ADS)

The Accelerating Moment Release (AMR) of seismicity before large earthquakes has been discussed by an increasing number of seismologists over recent years; however, most of their research is concentrated on theoretical descriptions based on statistical physics. In this paper, we investigate the laboratory AMR phenomenon of acoustic emission (AE), and attempt to understand the physical mechanism of AMR behavior from the point of view of rock deformation. AE data used in this paper are from a granitic porphyry (GP) sample with heterogeneous structure, including grains of different size and a naturally healed joint. Based on a stochastic AMR model, the microfracturing activity during rock deformation is analyzed. Three stages, Pre-AMR, AMR and nucleation, that cover the entire deformation period, are defined according to their different microfracturing features. The fractal structure of each stage is investigated. Our results indicate that the AE activity is highly sensitive to both the stress load and the rock structure. The AMR stage, in which the moderate AE events demonstrated typical AMR behaviors, features a process of stress concentration and stress transfer on the fault plane. The AMR stage had a constant stress load condition and was characterized by a much earlier increase of AE rate than the elevation of mean AE magnitude, both of which are consistent with the results derived from the damage rheology model (B en-Z ion and L yakhovsky, 2002). The AMR stage was immediately followed by the nucleation stage, caused by quasi-static/dynamic fracture of the main fault. Therefore, regarding the GP sample, the AMR stage is a long-term preparatory process for dynamic fault fracture.

Wang, Lifeng; Ma, Shengli; Ma, Li

2008-02-01

88

Evaluation of splashzone maintenance coating systems by accelerated laboratory testing and field trials  

SciTech Connect

Maintenance painting of platform splashzones is one of the most difficult offshore coating problems. There is a limited and frequently interrupted weather window for working, the temperature is generally low, the relative humidity is usually high and surfaces may be subjected to salt spray or complete immersion within a few hours of coating application. Once a coating is on the steel, it is continually wet and must resist abrasion and impact from the sea and from debris which is in the sea. In order to stand up to these conditions, splashzone coatings must adhere tightly to the steel, they must be tough and resilient and they must be resistant to the spread of local damage. Occidental's Piper and Claymore Platforms were installed in the North Sea in 1976 and 1977 respectively. The original splashzone coatings applied during fabrication were high-build vinyl systems over zinc silicate primers. The same coating systems were used on the platform topsides. By 1978 there was a need for coating repairs because the vinyls had poor abrasion resistance. It has proved impossible to use the original coating system for the repairs because it is intolerant of ambient conditions. Major maintenance painting programmes were planned for both platform splashzones in 1983. Surveys had shown that both splashzones required blasting to bare metal and recoating. Field trials and accelerated laboratory tests were used to select a coating system for the platform splashzones from nine alternative systems. The materials tested were ones presented by major manufacturers as their recommended splashzone systems. The coating systems ranged from coal tar epoxies to a very-high-technology system of primer injected into the grit-blasting nozzle followed by a single coat of high-build, solvent-free epoxy. Detailed descriptions of the coating systems are given in Table 1.

Tischuk, J.L.; Brebner, G.

1983-09-01

89

Science Archives at SLAC National Accelerator Laboratory, SLAC Archives and Research Library.  

National Technical Information Service (NTIS)

The idea for a two-mile linear accelerator at Stanford University was conceived in 1956, proposed in 1957, and authorized by the United States (US) Congress in 1961. Initially called 'Project M,' the venture was renamed 'The Stanford Linear Accelerator Ce...

J. M. Deken

2013-01-01

90

Los Alamos National Laboratory accelerator production of tritium project. Topical report, Radionuclide production experiment.  

National Technical Information Service (NTIS)

The accelerator production of tritium relies on a high-energy proton beam to produce spallation neutrons and lower mass residual nuclei. Radionuclide production over a wide energy range must be considered. The calculation of radionuclide production in a t...

J. L. Ullmann A. Gavron J. King

1993-01-01

91

Performance of the accelerator driver of Jefferson Laboratory's free-electron laser  

Microsoft Academic Search

The driver for Jefferson Lab's kW-level infrared free-electron laser (FEL) is a superconducting, recirculating accelerator that recovers about 75% of the electron-beam power and converts it to radiofrequency power. In achieving first lasing, the accelerator operated “straight-ahead” to deliver 38 MeV, 1.1 mA cw current through the wiggler for lasing at wavelengths in the vicinity of 5 ?m. Just prior

C. L. Bohn; S. Benson; G. Biallas; I. Campisi; D. Douglas; R. Evans; J. Fugitt; R. Hill; K. Jordan; G. Krafft; R. Li; L. Merminga; G. Neil; P. Piot; J. Preble; M. Shinn; T. Siggins; R. Walker; B. Yunn

1999-01-01

92

Overview of coupled bunch active damper systems at FNAL  

SciTech Connect

Beam intensities in all of the accelerators at Fermilab will increase significantly when the Main Injector becomes operational and will cause unstable oscillations in transverse position and energy. Places where the coupled bunch oscillations could dilute emittances include the Booster, Main Injector, and Tevatron. This paper provides an overview of the active feedback system upgrades which will be used to counteract the problem. It will explain the similarities between all the systems and will also explain design differences between longitudinal and transverse systems, fast sweeping systems, and systems for partially filled machines. Results from operational systems will also be shown. 7 refs., 4 figs., 1 tab.

Steimel, J.; Crisp, J.; Ma, Hengjie; Marriner, J.; McGinnis, D.

1996-05-01

93

Overview of coupled-bunch active damper systems at FNAL  

SciTech Connect

Beam intensities in all of the accelerators at Fermilab will increase significantly when the Main Injector becomes operational and will cause unstable oscillations in transverse position and energy. Places where the coupled bunch oscillations could dilute emittances include the Booster, Main Injector, and Tevatron. This paper provides an overview of the active feedback system upgrades which will be used to counteract the problem. It will explain the similarities between all the systems and will also explain design differences between longitudinal and transverse systems, fast sweeping systems, and systems for partially filled machines. Results from operational systems will also be shown. {copyright} {ital 1997 American Institute of Physics.}

Steimel, J.; Crisp, J.; Ma, H.; Marriner, J.; McGinnis, D. [Fermi National Accelerator Laboratory, P.O. Box 500 Batavia, Illinois 60510 (United States)

1997-01-01

94

Department of Energy finding of no significant impact, Low Energy Demonstration Accelerator, Los Alamos National Laboratory  

SciTech Connect

As part of the DOE`s need to maintain the capability of producing tritium in support of its historic and near-term stewardship of the nation`s nuclear weapons stockpile, the agency has recently completed a Programmatic Environmental Impact Statement for Tritium Supply and Recycling. The Environmental Assessment (EA) for the Low Energy Demonstration Accelerator (LEDA) at Technical Area (TA) 53, LANL, Los Alamos, New Mexico (DOE-EA-1147), March 1996, analyzes the DOE proposal to design, build, and test critical prototypical components of the accelerator system for tritium production, specifically the front-end, low-energy section of the accelerator at LANL. LEDA would be incrementally developed and tested in five separate stages over the next seven years. LEDA would be located at an existing building at TA-53; the LEDA components would be tested in order to verify equipment and prototype design and resolve related performance and production issues for future full-scale operation at Savannah River Site (SRS) in the event the APT plant is built. Production operations would not occur at LANL under the proposed action. The US DOE finds that there would be no significant impact from proceeding with its proposal to design, build, and test critical prototypical components of the accelerator system for tritium production, specifically the front-end, low-energy section of the accelerator, at TA-53, LANL. Based on the environmental assessment that analyses the potential environmental effects that would be expected to occur if the DOE were to design, build, and test prototypical components of the accelerator system for tritium production, the proposed action does not constitute a major federal action which would significantly affect the human environment within the meaning of NEPA. Therefore, no environmental impact statement is required for this proposal.

NONE

1996-08-01

95

Accelerator driven gamma and fast neutron radiography test-bed at Lawrence Livermore National Laboratory  

NASA Astrophysics Data System (ADS)

Accelerator driven fusion gammas and fast neutrons could provide unique radiography capabilities due to their ability to produce both high and low energy mono-energetic gammas and neutrons compared with broadband bremsstrahlung based x-ray sources. The possibility of simultaneously obtaining both gamma and neutron radiographs using one source could allow complex objects composed of a large range of low to high Z materials to be imaged. In this paper we review a 4 MV RFQ accelerator driven radiography test-bed at LLNL designed to study the physics involved in applying these dual output fusion reactions for radiography applications. First experimental neutron images from a carbon target are presented.

Tang, V.; Rusnak, B.; Falabella, S.; Hawkins, S.; McCarrick, J. F.; Wang, H.; Hall, J. M.; Ellsworth, J.

2013-04-01

96

Annual report 1991 of Munich University and Technical University Accelerator Laboratory. (Beschleunigerlaboratorium der Universitaet und der Technischen Universitaet Muenchen. Jahresbericht 1991).  

National Technical Information Service (NTIS)

The experimental work in the Accelerator Laboratory contains investigations of nuclear reactions and nuclear structure, studies of atomic physics and the application of nuclear physics methods in physics and in interdisciplinary research. These applicatio...

1992-01-01

97

Future Development Of The Flerov Laboratory Accelerator Complex (Project DRIBs-III)  

SciTech Connect

Future development of the FLNR accelerator complex (project DRIBs-III) includes modernization of existing cyclotrons, construction of a new experimental hall, creation of a new high current cyclotron and of next generation experimental set-ups. Realization of the project is planned for 2010-2016.

Gulbekian, G. G.; Dmitriev, S. N.; Itkis, M. G.; Oganessian, Yu. Ts.; Popeko, A. G. [Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, Dubna, 141980 (Russian Federation)

2010-04-30

98

Notes for Workshop on accelerator instrumentation, Brookhaven National Laboratory, October, 1989  

SciTech Connect

Instruments for monitoring the beam currents in accelerators are described, with emphasis on non-destructive monitors that do not intercept the beam. The spectral content observed on the output of such devices is analyzed for various bunch profiles. Stripline detectors, beam current transformers, and direct current transformers are described and analyzed.

Talman, R. (SSC Laboratory, Dallas, Texas (United States))

1990-10-02

99

Bulk ion acceleration and particle heating during magnetic reconnection in a laboratory plasmaa)  

NASA Astrophysics Data System (ADS)

Bulk ion acceleration and particle heating during magnetic reconnection are studied in the collisionless plasma of the Magnetic Reconnection Experiment (MRX). The plasma is in the two-fluid regime, where the motion of the ions is decoupled from that of the electrons within the ion diffusion region. The reconnection process studied here is quasi-symmetric since plasma parameters such as the magnitude of the reconnecting magnetic field, the plasma density, and temperature are compatible on each side of the current sheet. Our experimental data show that the in-plane (Hall) electric field plays a key role in ion heating and acceleration. The electrostatic potential that produces the in-plane electric field is established by electrons that are accelerated near the electron diffusion region. The in-plane profile of this electrostatic potential shows a "well" structure along the direction normal to the reconnection current sheet. This well becomes deeper and wider downstream as its boundary expands along the separatrices where the in-plane electric field is strongest. Since the in-plane electric field is 3-4 times larger than the out-of-plane reconnection electric field, it is the primary source of energy for the unmagnetized ions. With regard to ion acceleration, the Hall electric field causes ions near separatrices to be ballistically accelerated toward the outflow direction. Ion heating occurs as the accelerated ions travel into the high pressure downstream region. This downstream ion heating cannot be explained by classical, unmagnetized transport theory; instead, we conclude that ions are heated by re-magnetization of ions in the reconnection exhaust and collisions. Two-dimensional (2-D) simulations with the global geometry similar to MRX demonstrate downstream ion thermalization by the above mechanisms. Electrons are also significantly heated during reconnection. The electron temperature sharply increases across the separatrices and peaks just outside of the electron diffusion region. Unlike ions, electrons acquire energy mostly from the reconnection electric field, and the energy gain is localized near the X-point. However, the increase in the electron bulk flow energy remains negligible. These observations support the assertion that efficient electron heating mechanisms exist around the electron diffusion region and that the heat generated there is quickly transported along the magnetic field due to the high parallel thermal conductivity of electrons. Classical Ohmic dissipation based on the perpendicular Spitzer resistivity is too small to balance the measured heat flux, indicating the presence of anomalous electron heating.

Yoo, Jongsoo; Yamada, Masaaki; Ji, Hantao; Jara-Almonte, Jonathan; Myers, Clayton E.

2014-05-01

100

Rapid Acceleration Leads to Rapid Weakening in Earthquake-Like Laboratory Experiments  

NASA Astrophysics Data System (ADS)

After nucleation, a large earthquake propagates as an expanding rupture front along a fault. This front activates countless fault patches that slip by consuming energy stored in Earth’s crust. We simulated the slip of a fault patch by rapidly loading an experimental fault with energy stored in a spinning flywheel. The spontaneous evolution of strength, acceleration, and velocity indicates that our experiments are proxies of fault-patch behavior during earthquakes of moment magnitude (Mw) = 4 to 8. We show that seismically determined earthquake parameters (e.g., displacement, velocity, magnitude, or fracture energy) can be used to estimate the intensity of the energy release during an earthquake. Our experiments further indicate that high acceleration imposed by the earthquake’s rupture front quickens dynamic weakening by intense wear of the fault zone.

Chang, J. C.; Lockner, D. A.; Reches, Z.

2012-10-01

101

Rapid acceleration leads to rapid weakening in earthquake-like laboratory experiments  

NASA Astrophysics Data System (ADS)

We simulated the slip of a fault-patch during a large earthquake by rapidly loading an experimental, ring-shaped fault with energy stored in a spinning flywheel. The flywheel abruptly delivers a finite amount of energy by spinning the fault-patch that spontaneously dissipates the energy without operator intervention. We conducted 42 experiments on Sierra White granite (SWG) samples, and 24 experiments on Kasota dolomite (KD) samples. Each experiment starts by spinning a 225 kg disk-shaped flywheel to a prescribed angular velocity. We refer to this experiment as an "earthquake-like slip-event" (ELSE). The strength-evolution in ELSE experiments is similar to the strength-evolution proposed for earthquake models and observed in stick-slip experiments. Further, we found that ELSE experiments are similar to earthquakes in at least three ways: (1) slip driven by the release of a finite amount of stored energy; (2) pattern of fault strength evolution; and (3) seismically observed values, such as average slip, peak-velocity and rise-time. By assuming that the measured slip, D, in ELSE experiments is equivalent to the average slip during an earthquake, we found that ELSE experiments (D = 0.003-4.6 m) correspond to earthquakes in moment-magnitude range of Mw = 4-8. In ELSE experiments, the critical-slip-distance, dc, has mean values of 2.7 cm and 1.2 cm for SWG and KD, that are much shorter than the 1-10 m in steady-state classical experiments in rotary shear systems. We attribute these dc values, to ELSE loading in which the fault-patch is abruptly loaded by impact with a spinning flywheel. Under this loading, the friction-velocity relations are strikingly different from those under steady-state loading on the same rock samples with the same shear system (Reches and Lockner, Nature, 2010). We further note that the slip acceleration in ELSE evolves systematically with fault strength and wear-rate, and that the dynamic weakening is restricted to the period of intense acceleration (up to 25 m/s2 during ~0.1 s). Thus, the weakening distance, dc, is reached within the initial acceleration spike. These observations are not unique, and similar weakening-acceleration associations were reported in stick-slip, rotary shear, and impact shear experiments. These studies greatly differ from each other in slip distance, normal stress, acceleration, and slip-velocities with the outstanding commonality of abrupt loading and intense acceleration. We propose that impact loading induces extremely high strain-rates that significantly increase rock brittleness, fracture tendency, and fragmentation. We envision that these processes intensify fault wear as manifested in ELSE experiments by extremely high initial wear-rates. This intense, early wear generates a layer of fine-grain gouge that reduces the fault strength by powder-lubrication. Our analysis indicates that rapid acceleration associated with earthquake rupture accelerates fault weakening and shortens the weakening-distance.

Chang, J. C.; Lockner, D. A.; Reches, Z.

2012-12-01

102

Recent Developments on ALICE (Accelerators and Lasers In Combined Experiments) at Daresbury Laboratory  

SciTech Connect

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

Saveliev, Y M; Buckley, R K; Buckley, S R; Clarke, J A; Corlett, P A; Dunning, D J; Goulden, A R; Hill, S F; Jackson, F; Jamison, S P; Jones, J K; Jones, L B; Leonard, S; McIntosh, P A; McKenzie, J W; Middleman, K J; Militsyn, B L; Moss, A J; Muratori, B D; Orrett, J F; Pattalwar, S M; Phillips, P J; Scott, D J; Seddon, E A; Shepherd, B.J.A.; Smith, S L; Thompson, N; Wheelhouse, A E; Williams, P H; Harrison, P; Holder, D J; Holder, G M; Schofield, A L; Weightman, P; Williams, R L; Laundry, D; Powers, T; Priebe, G

2010-05-01

103

Rapid acceleration leads to rapid weakening in earthquake-like laboratory experiments  

USGS Publications Warehouse

After nucleation, a large earthquake propagates as an expanding rupture front along a fault. This front activates countless fault patches that slip by consuming energy stored in Earth’s crust. We simulated the slip of a fault patch by rapidly loading an experimental fault with energy stored in a spinning flywheel. The spontaneous evolution of strength, acceleration, and velocity indicates that our experiments are proxies of fault-patch behavior during earthquakes of moment magnitude (Mw) = 4 to 8. We show that seismically determined earthquake parameters (e.g., displacement, velocity, magnitude, or fracture energy) can be used to estimate the intensity of the energy release during an earthquake. Our experiments further indicate that high acceleration imposed by the earthquake’s rupture front quickens dynamic weakening by intense wear of the fault zone.

Chang, Jefferson C.; Lockner, David A; Reches, Z.

2012-01-01

104

Simulation of the laser acceleration experiment at the Fermilab/NICADD photoinjector laboratory  

SciTech Connect

The possibility of using laser beam to accelerate electrons in a waveguide structure with dimension much larger than the laser wavelength was proposed by Pantel and analytically investigated by Xie. In the present paper we present the status of our experimental plan to demonstrate the laser/e{sup -} interaction using an e{sup -} beam with initial energy of 40-50 MeV.

Piot, P.; /Fermilab; Tikhoplav, R.; Melissinos, A.C.; /Rochester U.

2005-05-01

105

Assembly and Test of SQ01b, a Nb3Sn Quadrupole Magnet for the LHC Accelerator Research Program  

SciTech Connect

The US LHC Accelerator Research Program (LARP) consists of four US laboratories (BNL, FNAL, LBNL, and SLAC) collaborating with CERN to achieve a successful commissioning of the LHC and to develop the next generation of Interaction Region magnets. In 2004, a large aperture Nb{sub 3}Sn racetrack quadrupole magnet (SQ01) has been fabricated and tested at LBNL. The magnet utilized four subscale racetrack coils and was instrumented with strain gauges on the support structure and directly over the coil's turns. SQ01 exhibited training quenches in two of the four coils and reached a peak field in the conductor of 10.4 T at a current of 10.6 kA. After the test, the magnet was disassembled, inspected with pressure indicating films, and reassembled with minor modifications. A second test (SQ01b) was performed at FNAL and included training studies, strain gauge measurements and magnetic measurements. Magnet inspection, test results, and magnetic measurements are reported and discussed, and a comparison between strain gauge measurements and 3D finite element computations is presented

Ferracin, P.; Ambrosio, G.; Bartlett, S. E.; Bordini, B.; Carcagno, R.H.; Caspi, S.; Dietderich, D.R.; Feher, S.; Gourlay, S.A.; Hafalia, A.R.; Lamm, M.J.; Lietzke, A.F.; Mattafirri, S.; McInturff, A.D.; Orris, D.F.; Pischalnikov, Y.M.; Sabbi, G.L.; Sylvester, C.D.; Tartaglia, M.A.; Velev, G.V.; Zlobin, A.V.; Kashikhin, V.V.

2006-06-01

106

SLAC's Channel on YouTube: Science Videos from the SLAC National Accelerator Laboratory  

DOE Data Explorer

SLAC's channel on YouTube features a sizeable collection of hour-long public lectures on high-interest science projects and discoveries. The artistic posters announcing each lecture are, themselves, worth the visit. A sampling of titles includes: • Deep Science: Mining for Dark Matter, Sunil Golwala • Particle Accelerator on a Chip, Christopher McGuinness • Life Redefined: Microbes Built with Arsenic, Sam Webb and Felisa Wolfe-Simon • Archaeopteryx: Bringing the Dino-Bird to Life, Uwe Bergmann • Smashing Protons: First Physics at the Large Hadron Collider, David Miller • Leading the Charge: Exotic New Materials for Future Devices, Yulin Chen • Ultimate Atomic Bling: Nanotechnology of Diamonds, Jeremy Dahl • Deep Secrets of the Neutrino: Physics Underground, P.C. Rowson • Molecules in the Spotlight, James Cryan • Zap! The X-Ray Laser is Born, Daniel Ratner • Journey to the Center of the Earth: Exploring High Pressure, Wendy L. Mao • Cosmic Accelerators: Engines of the Extreme Universe, Stefan Funk • Angels and Demons: The Science Behind the Scenes, Norman Graf • Black Holes, the Brightest Objects in the Universe, Jonathan McKinney • Water: The Strangest Liquid, Anders Nilsson • Big Machines and Big Science: 80 Years of Accelerators at Stanford, Gregory Loew • Antimatter: What Is It and Where Did It Go?, Aaron Roodman • How Plants Do It: Light, Oxygen, Action, Vittal Yachandra • The Mysteries of Diamonds: Bizarre History, Amazing Properties, Unique Applications, Harris Kagan • Cosmic Dawn: The First Star in the Universe, Tom Abel • From Atoms to Animals: The Vital Force in Biology, Roger Kornberg • Hunting the Elusive Higgs boson and the Origin of Mass, Lance Dixon • Dark Energy: What the...?, Risa Wechsler • The Dark Side of the Universe, Marusa Bradac • The Large Hadron Collider, Sarah Demers • Robots: Fantasy and Reality • Hydrogen: Fueling the Future, Jennifer Leisch • Making Molecular Movies: 10, 000,000,000,000 Frames per Second • The Violent Universe, Eduardo do Couto e Silva • A Comet on Earth: Results from the Stardust Mission, Sean Brennan • Whispers of the Big Bang, Sarah Church • The Hunt for Hidden Dimensions, JoAnne Hewett • Arsenic: The Silent Killer, Andrea Foster • Archimedes: Accelerator Reveals Ancient Text, Uwe Bergmann • Neutrinos Get Under Your Skin, Boris Kayser • LCLS: Ultrafast Science, Philip H. Bucksbaum • Smarter Drugs: How Protein Crystallography Revolutionizes Drug Design, Clyde Smith • Profiling the Invisible: Quantum Mechanics and the Unseen Universe, Michael Perskin • Physical Attraction: The Mysteries of Magnetism, Joachim Stohr • The Runaway Universe, Roger Blandford • Metals, Molecules, Life and Death, Graham George

107

Can Accelerators Accelerate Learning?  

SciTech Connect

The 'Young Talented' education program developed by the Brazilian State Funding Agency (FAPERJ)[1] makes it possible for high-schools students from public high schools to perform activities in scientific laboratories. In the Atomic and Molecular Physics Laboratory at Federal University of Rio de Janeiro (UFRJ), the students are confronted with modern research tools like the 1.7 MV ion accelerator. Being a user-friendly machine, the accelerator is easily manageable by the students, who can perform simple hands-on activities, stimulating interest in physics, and getting the students close to modern laboratory techniques.

Santos, A. C. F.; Fonseca, P.; Coelho, L. F. S. [Instituto de Fisica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil, Caixa Postal 68528, 21941-972 (Brazil)

2009-03-10

108

Advocacy for the Archives and History Office of the SLAC National Accelerator Laboratory: Stages and Methods  

Microsoft Academic Search

Advocating for the good of the SLAC Archives and History Office (AHO) has not been a one-time affair, nor has it been a one-method procedure. It has required taking time to ascertain the current and perhaps predict the future climate of the Laboratory, and it has required developing and implementing a portfolio of approaches to the goal of building a

Jean Marie Deken

2009-01-01

109

ATLAS: a proposal for a precision heavy ion accelerator at Argonne National Laboratory  

SciTech Connect

The objective of the proposed Argonne Tandem-Linac Accelerator System (ATLAS) is to provide precision beams of heavy ions for nuclear physics research in the region of projectile energies comparable to nuclear binding energies (5-25 MeV/A). By using the demonstrated potential of superconducting rf technology, beams of exceptional quality and flexibility can be obtained. The system is designed to provide beams with tandem-like energy resolution and ease of energy variation, the energy range is comparable to that of a approx. 50 MV tandem and, in addition, the beam will be bunched into very short (approx. 50 psec) pulses, permitting fast-timing measurements that can open up major new experimental approaches.

Not Available

1978-02-01

110

ACCELERATED SITE TECHNOLOGY DEPLOYMENT COST AND PERFORMANCE REPORT COMPARABILITY OF ISOCS INSTRUMENT IN RADIONUCLIDE CHARACTERICATION AT BROOKHAVEN NATIONAL LABORATORY  

SciTech Connect

This report describes a DOE Accelerated Site Technology Deployment project being conducted at Brookhaven National Laboratory to deploy innovative, radiological, in situ analytical techniques. The technologies are being deployed in support of efforts to characterize the Brookhaven Graphite Research Reactor (BGRR) facility, which is currently undergoing decontamination and decommissioning. This report focuses on the deployment of the Canberra Industries In Situ Object Counting System (ISOCS) and assesses its data comparability to baseline methods of sampling and laboratory analysis. The battery-operated, field deployable gamma spectrometer provides traditional spectra of counts as a function of gamma energy. The spectra are then converted to radionuclide concentration by applying innovative efficiency calculations using monte carlo statistical methods and pre-defined geometry templates in the analysis software. Measurement of gamma emitting radionuclides has been accomplished during characterization of several BGRR components including the Pile Fan Sump, Above Ground Ducts, contaminated cooling fans, and graphite pile internals. Cs-137 is the predominant gamma-emitting radionuclide identified, with smaller quantities of Co-60 and Am-241 detected. The Project used the Multi-Agency Radiation Survey and Site Investigation Manual guidance and the Data Quality Objectives process to provide direction for survey planning and data quality assessment. Analytical results have been used to calculate data quality indicators (DQI) for the ISOCS measurements. Among the DQIs assessed in the report are sensitivity, accuracy, precision, bias, and minimum detectable concentration. The assessment of the in situ data quality using the DQIs demonstrates that the ISOCS data quality can be comparable to definitive level laboratory analysis when the field instrument is supported by an appropriate Quality Assurance Project Plan. A discussion of the results obtained by ISOCS analysis of objects that could not be analyzed readily by conventional methods demonstrates a powerful application of the instrument. In conclusion, a comparison of costs associated with the analysis on the ISOCS instrument to the costs of conventional sampling and laboratory analysis is presented.

KALB,P.; LUCKETT,L.; MILLER,K.; GOGOLAK,C.; MILIAN,L.

2001-03-01

111

Search for Neutral Heavy Leptons in Neutrino-Nucleon Interactions at the Fnal Tevatron  

NASA Astrophysics Data System (ADS)

The search for Neutral Heavy Leptons (NHL) in the Neutrino-Nucleon (nu-N) interactions has been conducted using the CCFR Detector and the Fermilab Quad Triplet Beam (FNAL-E744 and FNAL-E770). No evidence for NHL was found in the charged current decay channel, NHL to mu^- + X. NHL with masses between 0.5 and 3.0 GeV/c ^2 were excluded for coupling to muons below 1 to 10^{-4} of Fermi strength, depending on the NHL mass. An excess of 5.2 +/- 2.3 NHL candidates, in the neutral current decay channel, NHL to nu + X, was found for events with the separation between the production vertex and the decay vertex greater than 2.3 meters. No evidence for NHL was found in the neutral current decay channel, NHL to nu + X for events with the separation between the production vertex and the decay vertex between 0.6 meters and 2.3 meters. NHL with masses between 0.5 and 2.0 GeV/c^2 were excluded for coupling to muon neutrinos below 1 to 5 times 10^{ -4} of Fermi strength, depending on the NHL mass. ftn*Research supported by the U.S. Department of Energy.

de Barbaro, Pawel

112

Accelerator development for the NRL (Naval Research Laboratory) free-electron-laser program. Final report, July 1981-April 1986  

SciTech Connect

Included in the report are descriptions of the final assembly and operation of the Linear Induction Accelerator(LIA), installation and testing of a new accelerating gap in the five-core stage of the accelerator to operate at 150 kV, and the moving of and modifications of the charging and firing controls for remote operation of the accelerator.

Lucey, R.; Putnam, S.

1988-06-01

113

Representing Value as Digital Object: A Discussion of Transferability and Anonymity; Digital Library Initiatives of the Deutsche Forschungsgemeinschaft; CrossRef Turns One; Fermi National Accelerator Laboratory (Fermilab).  

ERIC Educational Resources Information Center

Includes four articles that discuss the use of digital objects to represent value in a network environment; digital library initiatives at the central public funding organization for academic research in Germany; an application of the Digital Object Identifier System; and the Web site of the Fermi National Accelerator Laboratory. (LRW)

Kahn, Robert E.; Lyons, Patrice A.; Brahms, Ewald; Brand, Amy; van den Bergen, Mieke

2001-01-01

114

Electron-Cloud Build-up in the FNAL Main Injector  

SciTech Connect

We present a summary on ongoing simulation results for the electron-cloud buildup in the context of the proposed FNAL Main Injector (MI) intensity upgrade [1] in a fieldfree region at the location of the RFA electron detector [2]. By combining our simulated results for the electron flux at the vacuum chamber wall with the corresponding measurements obtained with the RFA we infer that the peak secondary electron yield (SEY) {delta}{sub max} is {approx}> 1.4, and the average electron density is n{sub e} {approx}> 10{sup 10} m{sup -3} at transition energy for the specific fill pattern and beam intensities defined below. The sensitivity of our results to several variables remains to be explored in order to reach more definitive results. Effects from the electron cloud on the beam are being investigated separately [3].

Furman, M.A.

2007-06-04

115

Initial far-field otr images generated by 120-GeV protons at FNAL.  

SciTech Connect

We have successfully imaged for the first time the angular distribution patterns of optical transition radiation (OTR) generated by 120-GeV proton beams passing through an Al metal plane. These experiments were performed at Fermilab (FNAL) with the same chamber, foil, and camera design as with the near-field experiments previously reported. In this case the lens-to-CID-chip separation was remotely adjusted to provide the focus-at- infinity, or far-field optical imaging. Data have been obtained in transport lines both before the antiproton production target and before the NuMI target with particle intensities of about 5 to 22 times 10{sup 12}. A two-foil interferometer calculation was also performed. Single-foil experimental and modeling results will be presented.

Lumpkin, A. H.; Scarpine, V. E.; Tassotto, G. R.; High Energy Physics; FNAL

2008-01-01

116

Design of 325 MHz single and triple spoke resonators at FNAL  

SciTech Connect

The proposed 8-GeV driver at FNAL is based on approximately 400 independently phased SC resonators. In this paper the design of 325 MHz Spoke Resonators, two single spoke resonators ({beta}=0.22 and {beta}=0.4) and a triple spoke resonator ({beta}=0.62), for the High Intensity Neutrino Source (HINS) front end is presented. We describe the optimization of the spoke resonators geometry, the goal being to minimize the E{sub peak}/E{sub acc} and B{sub peak}/E{sub acc} ratios. We report on the coupled ANSYS-MWS analysis on the resonators mechanical properties and power coupler RF design. The current status of mechanical design, slow tuning mechanism and cryostat are also presented.

Lanfranco, G.; Apollinari, G.; Gonin, I.; Khabiboulline, T.; McConologue, F.; Romanov, G.; Wagner, R.; /Fermilab

2006-08-01

117

International X-Band Linear Collider Accelerator Structure R&D  

Microsoft Academic Search

For more than fifteen years before the International Technology Recommendation Panel (ITRP) decision in August, 2004, there were intensive R&D activities and broad international collaboration among the groups at SLAC, KEK, FNAL, LLNL and other labs for the room temperature X-Band accelerator structures. The goal was to provide an optimized design of the main linac structure for the NLC (Next

J. W. Wang

2009-01-01

118

Recent experience in the fabrication and brazing of ceramic beam tubes for kicker magnets at FNAL  

SciTech Connect

Ceramic beam tubes are utilized in numerous kicker magnets in different accelerator rings at Fermi National Accelerator Laboratory. Kovar flanges are brazed onto each beam tube end, since kovar and high alumina ceramic have similar expansion curves. The tube, kovar flange, end piece, and braze foil (titanium/incusil) alloy brazing material are stacked in the furnace and then brazed in the furnace at 1000 C. The ceramic specified is 99.8% Alumina, Al{sub 2}O{sub 3}, a strong recrystallized high-alumina fabricated by slip casting. Recent experience at Fermilab with the fabrication and brazing of these tubes has brought to light numerous problems including tube breakage and cracking and also the difficulty of brazing the tube to produce a leak-tight joint. These problems may be due to the ceramic quality, voids in the ceramic, thinness of the wall, and micro-cracks in the ends which make it difficult to braze because it cannot fill tiny surface cracks which are caused by grain pullout during the cutting process. Solutions which are being investigated include lapping the ends of the tubes before brazing to eliminate the micro-cracks and also metallization of the tubes.

Ader, C.R.; Jensen, C.; Reilly, R.; Snee, D.; Wilson, J.H.; /Fermilab

2008-06-01

119

Data Plots from FNAL-E907: Main Injector Particle Production Experiment (MIPP)  

DOE Data Explorer

The Main Injector Particle Production Experiment (FNAL E-907, MIPP), situated in the Meson Center beamline at Fermilab, took data during the first half of 2005. MIPP was designed primarily as an experiment to measure and study in detail the dynamics associated with non-perturbative strong interactions. The primary physics motivation behind MIPP was to restart the study of non-perturbative QCD interactions, which constitute over 99% of the strong interaction cross section. The available data of that time were of poor quality and old and were not in easily accessible form. The Time Projection Chamber (TPC) [6] that was at the heart of the MIPP experiment represented the electronic equivalent of the bubble chamber with vastly superior data acquisition rates. It also digitized the charged tracks in three dimensions, obviating the need for track matching across stereo views. Coupled with the particle identification capability of MIPP, the data from MIPP was intended to add significantly to the knowledge base of non-perturbative QCD. One of the primary goals of MIPP was to verify a general scaling law of inclusive particle production that states that the ratio of a semi-inclusive cross section to an inclusive cross section involving the same particles is a function only of the missing mass squared (M2) of the system and not of the other two Mandelstam variables s and t, the center of mass energy squared and the momentum transfer squared, respectively. [Copied and edited from the following publication: The Main Injector Particle Production Experiment (MIPP) at Fermilab, Rajendran Raja, Institute of Physics (IOP) Publishing, Journal of Physics: Conference Series 9 (2005) 303 û 308, doi:10.1088/1742-6596/9/1/058 at www.iop.org/EJ/article/1742-6596/9/1/058/jpconf5_9_058.pdf] There are approximately 40 data plots available to the public from E907. A proposal to upgrade the MIPP experiment (E-P-960) has been deferred. See the MIPP homepage at http://ppd.fnal.gov/experiments/e907/

None

120

A LABORATORY SOIL-CONTACT DECAY TEST: AN ACCELERATED METHOD TO DETERMINE DURABILITY OF TREATED WOOD SHAKES  

Microsoft Academic Search

In this study, cross sections of preservative-treated shakes were evaluated in soil-contact decay tests using Gleophyllum trabeum. The number of preservatives by species combinations, used allowed evaluation of procedural aspects of this method. We conclude that the soil-contact decay test is a good tool for an accelerated evaluation of the durability of treated shakes. Experimental designs need to be structured

Rodney C. De Groot; Bessie Woodward

1996-01-01

121

Acceleration of exp 14 C BEAMS in Electrostatic Accelerators.  

National Technical Information Service (NTIS)

Operational problems in the production and acceleration of exp 14 C beams for nuclear structure research in Los Alamos National Laboratory's Van de Graaff accelerators are discussed. Methods for the control of contamination in ion sources, accelerators an...

L. J. Rowton J. R. Tesmer

1981-01-01

122

Accelerating Ocean Energy to the Marketplace – Environmental Research at the U.S. Department of Energy National Laboratories  

SciTech Connect

The U.S. Department of Energy (US DOE) has mobilized its National Laboratories to address the broad range of environmental effects of ocean and river energy development. The National Laboratories are using a risk-based approach to set priorities among environmental effects, and to direct research activities. Case studies will be constructed to determine the most significant environmental effects of ocean energy harvest for tidal systems in temperate estuaries, for wave energy installations in temperate coastal areas, wave installations in sub-tropical waters, and riverine energy installations in large rivers. In addition, the National Laboratories are investigating the effects of energy removal from waves, tides and river currents using numerical modeling studies. Laboratory and field research is also underway to understand the effects of electromagnetic fields (EMF), acoustic noise, toxicity from anti-biofouling coatings, effects on benthic habitats, and physical interactions with tidal and wave devices on marine and freshwater organisms and ecosystems. Outreach and interactions with stakeholders allow the National Laboratories to understand and mitigate for use conflicts and to provide useful information for marine spatial planning at the national and regional level.

Copping, Andrea E.; Cada, G. F.; Roberts, Jesse; Bevelhimer, Mark

2010-10-06

123

The new external microbeam facility at the 5 MV Tandetron accelerator laboratory in Madrid: beam characterisation and first results  

NASA Astrophysics Data System (ADS)

This paper describes the new external microbeam on the 15° beamline of the 5 MV Tandetron accelerator recently installed at the CMAM in Madrid. The focusing and beam extraction system was supplied by Oxford Microbeams Ltd. and consists of a high precision quadrupole doublet with an interchangeable Kapton window exit nozzle and front-viewing video microscope. The sample is positioned in the beam using a stepper motor stage. The beam current and beam profile have been determined under different experimental conditions. A simple method based on the signal processing of ion-induced luminescence from quartz targets has been used to determine the beam profile in two dimensions simultaneously, without scanning. This is the first step in the development of a real time beam profile monitoring system, which could be used as part of an automated beam focusing procedure. The beam line will be primarily devoted to archaeometry and cultural heritage studies. As an example we report the characterisation of two Tang appearance antique porcelains.

Enguita, Olga; Fernández-Jiménez, M. T.; García, G.; Climent-Font, A.; Calderón, T.; Grime, G. W.

2004-06-01

124

Accelerating the Whiteshell Laboratories Decommissioning Through the Implementation of a Projectized and Delivery-Focused Organization - 13074  

SciTech Connect

Whiteshell Laboratories (WL) is a nuclear research site in Canada that was commissioned in 1964 by Atomic Energy of Canada Limited. It covers a total area of approximately 4,375 hectares (10,800 acres) and includes the main campus site, the Waste Management Area (WMA) and outer areas of land identified as not used for or impacted by nuclear development or operations. The WL site employed up to 1100 staff. Site activities included the successful operation of a 60 MW organic liquid-cooled research reactor from 1965 to 1985, and various research programs including reactor safety research, small reactor development, fuel development, biophysics and radiation applications, as well as work under the Canadian Nuclear Fuel Waste Management Program. In 1997, AECL made a business decision to discontinue research programs and operations at WL, and obtained government concurrence in 1998. The Nuclear Legacy Liabilities Program (NLLP) was established in 2006 by the Canadian Government to remediate nuclear legacy liabilities in a safe and cost effective manner, including the WL site. The NLLP is being implemented by AECL under the governance of a Natural Resources Canada (NRCan)/AECL Joint Oversight Committee (JOC). Significant progress has since been made, and the WL site currently holds the only Canadian Nuclear Safety Commission (CNSC) nuclear research site decommissioning license in Canada. The current decommissioning license is in place until the end of 2018. The present schedule planned for main campus decommissioning is 30 years (to 2037), followed by institutional control of the WMA until a National plan is implemented for the long-term management of nuclear waste. There is an impetus to advance work and complete decommissioning sooner. To accomplish this, AECL has added significant resources, reorganized and moved to a projectized environment. This presentation outlines changes made to the organization, the tools implemented to foster projectization, and the benefits and positive impacts on schedule and delivery. A revised organizational structure was implemented in two phases, starting 2011 April 1, to align WL staff with the common goal of decommissioning the site through the direction of the WL Decommissioning Project General Manager. On 2011 September 1, the second phase of the reorganization was implemented and WL Decommissioning staff was organized under five Divisions: Programs and Regulatory Compliance, General Site Services, Decommissioning Strategic Planning, Nuclear Facilities and Project Delivery. A new Mission, Vision and Objectives were developed for the project, and several productivity enhancements are being implemented. These include the use of an integrated and fully re-sourced Site Wide Schedule that is updated and reviewed at Plan-of-the-Week meetings, improved work distribution throughout the year, eliminating scheduling 'push' mentality, project scoreboards, work planning implementation, lean practices and various process improvement initiatives. A revised Strategic Plan is under development that reflects the improved project delivery capabilities. As a result of these initiatives, and a culture change towards a projectized approach, the decommissioning schedule will be advanced by approximately 10 years. (authors)

Wilcox, Brian; Mellor, Russ; Michaluk, Craig [Atomic Energy of Canada Limited, Whiteshell Laboratories, Pinawa, Manitoba (Canada)] [Atomic Energy of Canada Limited, Whiteshell Laboratories, Pinawa, Manitoba (Canada)

2013-07-01

125

Proceedings of the First International Symposium on the Biological Interpretation of Dose from Accelerator-Produced Radiation, Held at the Lawrence Radiation Laboratory, Berkeley, California, March 13--16, 1967  

Microsoft Academic Search

The objective of the meeting was to provide a companion meeting to the ''First Symposium on Accelerator Radiation Dosimetry and Experience'' which was held November 3-5, 1965, at the Brookhaven National Laboratory. This first symposium was limited in scope to an intensified discussion of dosimetry techniques. The biology which is associated with high energy radiation was specifically excluded, since it

Wallace

1967-01-01

126

EDITORIAL: Laser and plasma accelerators Laser and plasma accelerators  

Microsoft Academic Search

This special issue on laser and plasma accelerators illustrates the rapid advancement and diverse applications of laser and plasma accelerators. Plasma is an attractive medium for particle acceleration because of the high electric field it can sustain, with studies of acceleration processes remaining one of the most important areas of research in both laboratory and astrophysical plasmas. The rapid advance

Robert Bingham

2009-01-01

127

Investigations of the output energy deviation and other parameters during commissioning of the four-rod radio frequency quadrupole at the Fermi National Accelerator Laboratory  

NASA Astrophysics Data System (ADS)

After 30 years of operation, the Cockcroft-Walton based injector at the Fermi National Accelerator Laboratory has been replaced by a new beam line including a dimpled magnetron 35 keV source in combination with a 750 keV four-rod radio frequency quadrupole (RFQ). The new injector is followed by the existing drift tube linac. Prior to installation, a test beam line was built which included the magnetron source and the four-rod RFQ with a number of beam measurement instrumentation. The first beam test with the RFQ showed an output energy deviation greater than 2.5%. Other problems also showed up which led to investigations of the output energy, power consumption and transmission properties using rf simulations which were complemented with additional beam measurements. The sources of this deviation and the mechanical modifications of the RFQ to solve this matter will be presented in this paper. Meanwhile, the nominal output energy of 750 keV has been confirmed and the new injector with the four-rod RFQ is in full operation.

Schmidt, J. S.; Koubek, B.; Schempp, A.; Tan, C. Y.; Bollinger, D. S.; Duel, K. L.; Karns, P. R.; Pellico, W. A.; Scarpine, V. E.; Schupbach, B. A.; Kurennoy, S. S.

2014-03-01

128

High-intensity accelerators  

SciTech Connect

The design of high-intensity accelerators is described, using examples of machines being built at the Los Alamos National Laboratory. The major design problem with these accelerators is associated with control of beam loss when accelerator intensity is increased. Beam dynamics, beam loss, and the radio-frequency quadrupole structure are discussed in the first part of the chapter followed by an explanation of plans to achieve high-intensity operation in three projects: the Fusion Material Irradiation Tests (a joint effort with the Hanford Development Laboratory in Richland, Washington), the Proton Storage Ring (an addition to the LAMPF accelerator), and the Racetrack Microtron Project (with the National Bureau of Standards).

Knapp, E.A.

1981-01-01

129

Digitral Down Conversion Technology for Tevatron Beam Line Tuner at FNAL  

SciTech Connect

Fermilab is presently in Run II collider operations and is developing instrumentation to improve luminosity. Improving the orbit matching between accelerator components using a Beam Line Tuner (BLT) can improve the luminosity. Digital Down Conversion (DDC) has been proposed as a method for making more accurate beam position measurements. Fermilab has implemented a BLT system using a DDC technique to measure orbit oscillations during injections from the Main Injector to the Tevatron. The output of a fast ADC is downconverted and filtered in software. The system measures the x and y positions, the intensity, and the time of arrival for each proton or antiproton bunch, on a turn-by-turn basis, during the first 1024 turns immediately following injection. We present results showing position, intensity, and time of arrival for both injected and coasting beam. Initial results indicate a position resolution of {approx}20 to 40 microns and a phase resolution of {approx}25 ps.

Schappert, W.; Lorman, E.; Scarpine, V.; Ross, M.C.; Sebek, J.; Straumann, T.; /Fermilab /SLAC

2008-03-17

130

US Particle Accelerators at Age 50.  

ERIC Educational Resources Information Center

Reviews the development of accelerators over the past 50 years. Topics include: types of accelerators, including cyclotrons; sociology of accelerators (motivation, financing, construction, and use); impact of war; national laboratories; funding; applications; future projects; foreign projects; and international collaborations. (JN)

Wilson, R. R.

1981-01-01

131

Extruded Scintillator for the Calorimetry Applications.  

National Technical Information Service (NTIS)

An extrusion line has been installed and successfully operated at FNAL (Fermi National Accelerator Laboratory) in collaboration with NICADD (Northern Illinois Center for Accelerator and Detector Development). This new Facility will serve to further develo...

A. Dyshkant A. Pla-Dalmau D. Beznosko V. Rykalin

2006-01-01

132

Search for the eta_b meson via the exclusive decay mode eta_b meson going to neutral kaon(short)-kaon(+)-antipion in the BABAR experiment at SLAC National Accelerator Laboratory  

Microsoft Academic Search

In this thesis we describe a search for the etab meson via exclusive decay mode etab --> K0s K+pi--, K0s --> pi+pi-- using 369.4 fb-1 of run 1-5 data in BaBar experiment at SLAC National Accelerator Laboratory. We developed a scan fit technique based on Unbinned Extended Maximum likelihood fitting. Using this technique We estimated upper limit of branching fraction

Xurong Chen

2008-01-01

133

Acceleration in astrophysics  

SciTech Connect

The origin of cosmic rays and applicable laboratory experiments are discussed. Some of the problems of shock acceleration for the production of cosmic rays are discussed in the context of astrophysical conditions. These are: The presumed unique explanation of the power law spectrum is shown instead to be a universal property of all lossy accelerators; the extraordinary isotropy of cosmic rays and the limited diffusion distances implied by supernova induced shock acceleration requires a more frequent and space-filling source than supernovae; the near perfect adiabaticity of strong hydromagnetic turbulence necessary for reflecting the accelerated particles each doubling in energy roughly 10{sup 5} to {sup 6} scatterings with negligible energy loss seems most unlikely; the evidence for acceleration due to quasi-parallel heliosphere shocks is weak. There is small evidence for the expected strong hydromagnetic turbulence, and instead, only a small number of particles accelerate after only a few shock traversals; the acceleration of electrons in the same collisionless shock that accelerates ions is difficult to reconcile with the theoretical picture of strong hydromagnetic turbulence that reflects the ions. The hydromagnetic turbulence will appear adiabatic to the electrons at their much higher Larmor frequency and so the electrons should not be scattered incoherently as they must be for acceleration. Therefore the electrons must be accelerated by a different mechanism. This is unsatisfactory, because wherever electrons are accelerated these sites, observed in radio emission, may accelerate ions more favorably. The acceleration is coherent provided the reconnection is coherent, in which case the total flux, as for example of collimated radio sources, predicts single charge accelerated energies much greater than observed.

Colgate, S.A.

1993-12-31

134

Plasma Accelerator.  

National Technical Information Service (NTIS)

The accelerator has potential applications in aerodynamic testing, as a source of high-speed plasma for research and as a propulsion system for space vehicles. The accelerator is capable of steady flow operation. The arrangement includes an accelerating c...

G. P. Wood A. F. Carter A. Busemann

1965-01-01

135

Overview of accelerators in medicine  

SciTech Connect

Accelerators used for medicine include synchrotrons, cyclotrons, betatrons, microtrons, and electron, proton, and light ion linacs. Some accelerators which were formerly found only at physics laboratories are now being considered for use in hospital-based treatment and diagnostic facilities. This paper presents typical operating parameters for medical accelerators and gives specific examples of clinical applications for each type of accelerator, with emphasis on recent developments in the field.

Lennox, A.J. [Fermi National Accelerator Lab., Batavia, IL (US)]|[Rush Univ., Chicago, IL (US)

1993-06-01

136

Accelerator and High-Energy Physics Multimedia and Images from Fermilab  

DOE Data Explorer

Fermilab's Visual Media Services (VMS) website makes available a collection of videos, a streaming video archive, photos, and animations. The collection dates back to 1983 and includes information about items on old tapes. Each category can be viewed as a gallery or searched through an interface. While many of these items deal with buildings, people, special events related to FNAL's mission, etc., it is worth searching for scientific images of accelerator events. Print images that have been used in press releases and at poster sessions can also be browsed at this site.

137

Vacuum Beat Wave Acceleration  

Microsoft Academic Search

The Vacuum Beat Wave Accelerator (VBWA) utilizes two laser beams with differing wavelengths to accelerate particles in vacuo.(Sprangle et al., Opt. Comm. 124), 69 (1996); Esarey et al., Phys. Rev. E 52, 5443 (1995). The mechanism relies on the v×B force, circumventing the so-called Lawson-Woodward theorem. A proof-of-principle experiment will be performed at the Naval Research Laboratory, based on design

C. I. Moore; B. Hafizi; E. Esarey; P. Sprangle; A. Ganguly; J. L. Hirshfield

1997-01-01

138

Diagnostics for induction accelerators  

SciTech Connect

The induction accelerator was conceived by N. C. Christofilos and first realized as the Astron accelerator that operated at LLNL from the early 1960`s to the end of 1975. This accelerator generated electron beams at energies near 6 MeV with typical currents of 600 Amperes in 400 ns pulses. The Advanced Test Accelerator (ATA) built at Livermore`s Site 300 produced 10,000 Ampere beams with pulse widths of 70 ns at energies approaching 50 MeV. Several other electron and ion induction accelerators have been fabricated at LLNL and LBNL. This paper reviews the principal diagnostics developed through efforts by scientists at both laboratories for measuring the current, position, energy, and emittance of beams generated by these high current, short pulse accelerators. Many of these diagnostics are closely related to those developed for other accelerators. However, the very fast and intense current pulses often require special diagnostic techniques and considerations. The physics and design of the more unique diagnostics developed for electron induction accelerators are presented and discussed in detail.

Fessenden, T.J.

1996-04-01

139

Accelerator summary  

NASA Astrophysics Data System (ADS)

A summary of the accelerator topics (CW electron accelerators, heavy ion colliders, kaon factories, polarized proton beams, and cooling rings) discussed in the 1984 conference on ``Intersections Between Particle and Nuclear Physics'' (Steamboat Springs) is presented. (AIP)

Mills, F. E.

1984-11-01

140

Accelerator summary  

SciTech Connect

A summary of the accelerator topics (CW electron accelerators, heavy ion colliders, kaon factories, polarized proton beams, and cooling rings) discussed in the 1984 conference on ''Intersections Between Particle and Nuclear Physics'' (Steamboat Springs) is presented. (AIP)

Mills, F.E.

1984-11-15

141

Future accelerators (?)  

SciTech Connect

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

2003-08-21

142

Space Radiation Effects Laboratory.  

National Technical Information Service (NTIS)

The SREL User's Handbook is designed to provide information needed by those who plan experiments involving the accelerators at this laboratory. Thus the Handbook will contain information on the properties of the machines, the beam parameters, the faciliti...

1969-01-01

143

Tethered gravity laboratories study  

NASA Technical Reports Server (NTRS)

The following subject areas are covered: (1) thermal control issues; (2) attitude control sybsystem; (3) configuration constraints; (4) payload; (5) acceleration requirements on Variable Gravity Laboratory (VGL); and (6) VGL configuration highlights.

Lucchetti, F.

1989-01-01

144

Accelerator Design and R&D for the ILC  

NASA Astrophysics Data System (ADS)

Since the formation of the Global Design Effort in early 2005, substantial progress has been made on the ILC design and a coordinated international program of R&D has been launched. R&D projects address the entire accelerator from the electron and positron sources to the damping rings and bunch compressors, main linacs and beam delivery system. Test facilities at DESY, FNAL, KEK and SLAC support a wide variety of experiments and hardware development. New initiatives include the proposed final focus test facility at KEK (ATF2) and an instrumentation and IR test facility at SLAC (ESA) as well as experiments on existing machines around the world. The extensive R&D program on superconducting RF will be covered separately.

Phinney, Nan

2006-04-01

145

Biomedical accelerator mass spectrometry  

NASA Astrophysics Data System (ADS)

Ultrasensitive SIMS with accelerator based spectrometers has recently begun to be applied to biomedical problems. Certain very long-lived radioisotopes of very low natural abundances can be used to trace metabolism at environmental dose levels ( [greater-or-equal, slanted] z mol in mg samples). 14C in particular can be employed to label a myriad of compounds. Competing technologies typically require super environmental doses that can perturb the system under investigation, followed by uncertain extrapolation to the low dose regime. 41Ca and 26Al are also used as elemental tracers. Given the sensitivity of the accelerator method, care must be taken to avoid contamination of the mass spectrometer and the apparatus employed in prior sample handling including chemical separation. This infant field comprises the efforts of a dozen accelerator laboratories. The Center for Accelerator Mass Spectrometry has been particularly active. In addition to collaborating with groups further afield, we are researching the kinematics and binding of genotoxins in-house, and we support innovative uses of our capability in the disciplines of chemistry, pharmacology, nutrition and physiology within the University of California. The field can be expected to grow further given the numerous potential applications and the efforts of several groups and companies to integrate more the accelerator technology into biomedical research programs; the development of miniaturized accelerator systems and ion sources capable of interfacing to conventional HPLC and GMC, etc. apparatus for complementary chemical analysis is anticipated for biomedical laboratories.

Freeman, Stewart P. H. T.; Vogel, John S.

1995-05-01

146

Acceleration of Time Integration  

SciTech Connect

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

2007-01-01

147

Inverse free electron laser accelerator  

SciTech Connect

The study of the INVERSE FREE ELECTRON LASER, as a potential mode of electron acceleration, is being pursued at Brookhaven National Laboratory. Recent studies have focussed on the development of a low energy, high gradient, multi stage linear accelerator. The elementary ingredients for the IFEL interaction are the 50 MeV Linac e[sup [minus

Fisher, A.; Gallardo, J.; Sandweiss, J.; van Steenbergen, A. (National Synchrotron Light Source and Physics Department, Brookhaven National Laboratory, Upton, New York 11973 (United States))

1992-07-01

148

Inverse Free Electron Laser accelerator  

SciTech Connect

The study of the INVERSE FREE ELECTRON LASER, as a potential mode of electron acceleration, is being pursued at Brookhaven National Laboratory. Recent studies have focussed on the development of a low energy, high gradient, multi stage linear accelerator. The elementary ingredients for the IFEL interaction are the 50 MeV Linac e[sup [minus

Fisher, A.; Gallardo, J.; van Steenbergen, A. (Brookhaven National Lab., Upton, NY (United States)); Sandweiss, J. (Yale Univ., New Haven, CT (United States))

1992-09-01

149

Review of Activities using the Pulsed Neutron Facility and 2.5-GeV Electron Linac at Pohang Accelerator Laboratory  

NASA Astrophysics Data System (ADS)

We report on activities using a pulsed neutron facility consisting of an electron linear accelerator, a water-cooled Ta target with a water moderator, and a 12 m time-of-flight path. It is possible to measure neutron total cross sections in the neutron energy range from 0.01 eV to a few hundred eV by using the neutron time-of-flight method; photo-neutron cross sections can also measure by using the bremsstrahlung from the electron linac. A 6LiZnS(Ag) glass scintillator was used as a neutron detector. The neutron flight path from the water-cooled Ta target to the neutron detector was 12.1 m. In this paper, we report total cross sections of Nb and also resonance parameters obtained using the SAMMY fitting program. The present results are compared with the previous experimental results and the evaluated data in ENDF/B-VII. We also report on the mass-yield distribution of fission products in the 2.5-GeV bremsstrahlung-induced fission of natPb and 209Bi measured at the 2.5-GeV electron linac using a recoil catcher and an off-line ?-ray spectrometric technique.

Kim, Guinyun; Lee, Manwoo; Kim, Kyung Sook; Yang, Sungchul; Kim, Eunae; Shvetshov, Valery; Cho, Moo-Hyun; Naik, Haladhara

2011-12-01

150

Review of Activities using the Pulsed Neutron Facility and 2.5-GeV Electron Linac at Pohang Accelerator Laboratory  

SciTech Connect

We report on activities using a pulsed neutron facility consisting of an electron linear accelerator, a water-cooled Ta target with a water moderator, and a 12 m time-of-flight path. It is possible to measure neutron total cross sections in the neutron energy range from 0.01 eV to a few hundred eV by using the neutron time-of-flight method; photo-neutron cross sections can also measure by using the bremsstrahlung from the electron linac. A {sup 6}LiZnS(Ag) glass scintillator was used as a neutron detector. The neutron flight path from the water-cooled Ta target to the neutron detector was 12.1 m. In this paper, we report total cross sections of Nb and also resonance parameters obtained using the SAMMY fitting program. The present results are compared with the previous experimental results and the evaluated data in ENDF/B-VII. We also report on the mass-yield distribution of fission products in the 2.5-GeV bremsstrahlung-induced fission of {sup nat}Pb and {sup 209}Bi measured at the 2.5-GeV electron linac using a recoil catcher and an off-line {gamma}-ray spectrometric technique.

Kim, Guinyun; Lee, Manwoo; Kim, Kyung Sook; Yang, Sungchul [Department of Physics,Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 702-701 (Korea, Republic of); Kim, Eunae; Shvetshov, Valery; Cho, Moo-Hyun [Division of Advanced Nuclear Engineering, Pohang University of Science and Technology, San 31, Hyoja-dong, Nam-gu, Pohang 790-784 (Korea, Republic of); Naik, Haladhara [Radiochemistry Division, Bhabha Atomic Research Center, Trombay, Mumbai 400085 (India)

2011-12-13

151

Accelerator and electrodynamics capability review  

SciTech Connect

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

Jones, Kevin W [Los Alamos National Laboratory

2010-01-01

152

HIGH GRADIENT INDUCTION ACCELERATOR  

SciTech Connect

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

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

2007-06-21

153

Plasma based charged-particle accelerators  

Microsoft Academic Search

Studies of charged-particle acceleration processes remain one of the most important areas of research in laboratory, space and astrophysical plasmas. In this paper, we present the underlying physics and the present status of high gradient and high energy plasma accelerators. We will focus on the acceleration of charged particles to relativistic energies by plasma waves that are created by intense

R Bingham; J T Mendonça; P K Shukla

2004-01-01

154

Rail accelerator research at Lewis Research Center  

NASA Technical Reports Server (NTRS)

A rail accelerator was chosen for study as an electromagnetic space propulsion device because of its simplicity and existing technology base. The results of a mission feasibility study using a large rail accelerator for direct launch of ton-size payloads from the Earth's surface to space, and the results of initial tests with a small, laboratory rail accelerator are presented. The laboratory rail accelerator has a bore of 3 by 3 mm and has accelerated 60 mg projectiles to velocities of 300 to 1000 m/s. Rail materials of Cu, W, and Mo were tested for efficiency and erosion rate.

Kerslake, W. R.; Cybyk, B. Z.

1982-01-01

155

Accelerator simulation of astrophysical processes  

NASA Technical Reports Server (NTRS)

Phenomena that involve accelerated ions in stellar processes that can be simulated with laboratory accelerators are described. Stellar evolutionary phases, such as the CNO cycle, have been partially explored with accelerators, up to the consumption of He by alpha particle radiative capture reactions. Further experimentation is indicated on reactions featuring N-13(p,gamma)O-14, O-15(alpha, gamma)Ne-19, and O-14(alpha,p)F-17. Accelerated beams interacting with thin foils produce reaction products that permit a determination of possible elemental abundances in stellar objects. Additionally, isotopic ratios observed in chondrites can be duplicated with accelerator beam interactions and thus constraints can be set on the conditions producing the meteorites. Data from isotopic fractionation from sputtering, i.e., blasting surface atoms from a material using a low energy ion beam, leads to possible models for processes occurring in supernova explosions. Finally, molecules can be synthesized with accelerators and compared with spectroscopic observations of stellar winds.

Tombrello, T. A.

1983-01-01

156

SLAC (Stanford Linear Accelerator Center) Site Design Aesthetics.  

National Technical Information Service (NTIS)

Stanford Linear Accelerator Center (SLAC) is a single mission Laboratory dedicated to basic research in high energy particle physics. SLAC site also houses Stanford Synchrotron Radiation Laboratory (SSRL) which is a multi-mission laboratory for research u...

F. F. Hall

1985-01-01

157

Podcast: Acceleration  

NSDL National Science Digital Library

The Podcast: Acceleration is a segment of the Force and Motion Short Course. The podcast is 2 minutes 13 seconds in duration. Presented by science experts and NSTA staff, the NSTA Online Short Courses are professional development opportunities de

2009-07-06

158

A microwave inverse Cerenkov Accelerator  

SciTech Connect

The objective of this Phase II SBIR research program was to complete the final design originated during Phase I for a prototype Microwave Inverse Cerenkov Accelerator (MICA), to fabricate the-prototype MICA, and to test its performance as an electron accelerator. This report contains details of the design, predictions of accelerator performance, results of cold tests on the MICA structure, and details of the installation of MICA on the Yale Beam Physics Laboratory 6-MeV beamline. Discussion of future work is also included.

Jay L. Hirshfield

1999-07-01

159

Acceleration Studies  

NASA Technical Reports Server (NTRS)

Work to support the NASA MSFC Acceleration Characterization and Analysis Project (ACAP) was performed. Four tasks (analysis development, analysis research, analysis documentation, and acceleration analysis) were addressed by parallel projects. Work concentrated on preparation for and implementation of near real-time SAMS data analysis during the USMP-1 mission. User support documents and case specific software documentation and tutorials were developed. Information and results were presented to microgravity users. ACAP computer facilities need to be fully implemented and networked, data resources must be cataloged and accessible, future microgravity missions must be coordinated, and continued Orbiter characterization is necessary.

Rogers, Melissa J. B.

1993-01-01

160

UCLA Neptune Facility for Advanced Accelerator Studies  

SciTech Connect

The Neptune Laboratory at UCLA is being used for exploring concepts useful for advanced accelerators. This facility hosts a TW-class CO2 laser system and a high-brightness photoinjector producing a 14 MeV electron beam. The goal for the laboratory is to carry out experiments on high-gradient acceleration of externally injected electrons in both laser-driven relativistic plasma waves and EM laser field in vacuum. Experiments on plasma beat-wave acceleration using a prebunched electron beam, a high-energy gain 10-{mu}m inverse free electron laser accelerator, longitudinal electron beam shaping and laser based light-sources are planned.

Tochitsky, Sergei Ya.; Clayton, Christopher E.; Marsh, Kenneth A.; Joshi, Chandrashekhar [Neptune Laboratory, Department of Electrical Engineering, University of California at Los Angeles, 405 Hilgard avenue, Los Angeles, CA 90095 (United States); Rosenzweig, James B.; Pellegrini, Claudio [Neptune Laboratory, Department of Physics, University of California at Los Angeles, 405 Hilgard avenue, Los Angeles, CA 90095 (United States)

2004-12-07

161

Brazing Techniques for Side-Coupled Electron Accelerator Structures.  

National Technical Information Service (NTIS)

The collaboration between the Los Alamos National Laboratory and the National Bureau of Standards (NBS), started in 1979, has led to the development of an advanced c-w microtron accelerator design. The four 2380-MHz NBS accelerating structures, containing...

L. D. Hansborough W. L. Clark R. A. DePaula F. A. Martinez P. L. Roybal

1986-01-01

162

Advanced Test Accelerator: A High-Current Induction Linac.  

National Technical Information Service (NTIS)

The Advanced Test Accelerator (ATA) is a linear induction accelerator being built at Lawrence Livermore National Laboratory. The aim of the ATA, together with its associated physics program is the research and development necessary to resolve whether part...

E. G. Cook D. L. Birx L. L. Reginato

1982-01-01

163

Steady Gradually Accelerating Flow in a Smooth Open Channel.  

National Technical Information Service (NTIS)

Laboratory experiments on the structure of spatially accelerating flows in a smooth open channel are reported. The influence of acceleration on the bottom shear stress are investigated. The most important conclusions of the study are summarized as follows...

A. H. Cardoso W. H. Graf G. Gust

1991-01-01

164

Particle acceleration  

NASA Technical Reports Server (NTRS)

Data is compiled from Solar Maximum Mission and Hinothori satellites, particle detectors in several satellites, ground based instruments, and balloon flights in order to answer fundamental questions relating to: (1) the requirements for the coronal magnetic field structure in the vicinity of the energization source; (2) the height (above the photosphere) of the energization source; (3) the time of energization; (4) transistion between coronal heating and flares; (5) evidence for purely thermal, purely nonthermal and hybrid type flares; (6) the time characteristics of the energization source; (7) whether every flare accelerates protons; (8) the location of the interaction site of the ions and relativistic electrons; (9) the energy spectra for ions and relativistic electrons; (10) the relationship between particles at the Sun and interplanetary space; (11) evidence for more than one acceleration mechanism; (12) whether there is single mechanism that will accelerate particles to all energies and also heat the plasma; and (13) how fast the existing mechanisms accelerate electrons up to several MeV and ions to 1 GeV.

Vlahos, L.; Machado, M. E.; Ramaty, R.; Murphy, R. J.; Alissandrakis, C.; Bai, T.; Batchelor, D.; Benz, A. O.; Chupp, E.; Ellison, D.

1986-01-01

165

Plasma accelerator  

DOEpatents

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

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

2002-01-01

166

Future Accelerators.  

National Technical Information Service (NTIS)

These lectures contain (a) an overview of what might be learned from experiments at future (e bar)e, pp and ep colliders, (b) a review of limitations on circular and linear colliders, and (c) a description of some novel ideas for acceleration.

C. H. Llewellyn Smith

1986-01-01

167

Mental Acceleration.  

ERIC Educational Resources Information Center

Use of the term "acceleration" to describe interventions to enhance children's intellectual potential is inappropriate, as the term cannot by justified from the standpoint of mental measurement, mental growth, genetics, or education. Maximizing a child's potential through creation of stimulating environments is recommended rather than…

Elkind, David

1988-01-01

168

Acceleration Environment of the International Space Station  

NASA Technical Reports Server (NTRS)

Measurement of the microgravity acceleration environment on the International Space Station has been accomplished by two accelerometer systems since 2001. The Microgravity Acceleration Measurement System records the quasi-steady microgravity environment, including the influences of aerodynamic drag, vehicle rotation, and venting effects. Measurement of the vibratory/transient regime, comprised of vehicle, crew, and equipment disturbances, has been accomplished by the Space Acceleration Measurement System-II. Until the arrival of the Columbus Orbital Facility and the Japanese Experiment Module, the location of these sensors, and therefore, the measurement of the microgravity acceleration environment, has been limited to within the United States Laboratory. Japanese Aerospace Exploration Agency has developed a vibratory acceleration measurement system called the Microgravity Measurement Apparatus which will be deployed within the Japanese Experiment Module to make distributed measurements of the Japanese Experiment Module's vibratory acceleration environment. Two Space Acceleration Measurement System sensors from the United States Laboratory will be re-deployed to support vibratory acceleration data measurement within the Columbus Orbital Facility. The additional measurement opportunities resulting from the arrival of these new laboratories allows Principal Investigators with facilities located in these International Space Station research laboratories to obtain microgravity acceleration data in support of their sensitive experiments. The Principal Investigator Microgravity Services project, at NASA Glenn Research Center, in Cleveland, Ohio, has supported acceleration measurement systems and the microgravity scientific community through the processing, characterization, distribution, and archival of the microgravity acceleration data obtained from the International Space Station acceleration measurement systems. This paper summarizes the PIMS capabilities available to the International Space Station scientific community, introduces plans for extending microgravity analysis results to the newly arrived scientific laboratories, and provides summary information for known microgravity environment disturbers.

McPherson, Kevin; Kelly, Eric; Keller, Jennifer

2009-01-01

169

GRAPE Accelerators  

NASA Astrophysics Data System (ADS)

I'll overview the past, present, and future of the GRAPE project, which started as the effort to design and develop specialized hardware for gravitational N-body problem. The current hardware, GRAPE-DR, has an architecture quite different from previous GRAPEs, in the sense that it is a collection of small, but programmable processors, while previous GRAPEs had hardwired pipelines. I'll discuss pros and cons of these two approaches, comparisons with other accelerators and future directions.

Makino, Junichiro

2011-04-01

170

MUON ACCELERATION  

SciTech Connect

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

BERG,S.J.

2003-11-18

171

Inverse free-electron laser accelerator development  

SciTech Connect

The study of the Inverse Free-Electron Laser, as a potential mode of electron acceleration, has been pursued at Brookhaven National Laboratory for a number of years. More recent studies focused on the development of a low energy (few GeV), high gradient, multistage linear accelerator. The authors are presently designing a short accelerator module which will make use of the 50 MeV linac beam and high power (2 {times} 10{sup 11} W) CO{sub 2} laser beam of the Accelerator Test Facility (ATF) at the Center for Accelerator Physics (CAP), Brookhaven National Laboratory. These elements will be used in conjunction with a fast excitation (300 {mu}sec pulse duration) variable period wiggler, to carry out an accelerator demonstration stage experiment.

Fisher, A.; Gallardo, J.; Steenbergen, A. van [Brookhaven National Lab., Upton, NY (United States); Sandweiss, J. [Yale Univ., New Haven, CT (United States). Dept. of Physics; Fang, J.M. [Columbia Univ., New York, NY (United States). Dept. of Applied Physics

1994-06-01

172

Advanced accelerator research at Argonne  

Microsoft Academic Search

A facility with which to experimentally measure methods of advanced acceleration is at the point of completion at Argonne National Laboratory. The new facility consists a system which produces pulse ''doublets'' of energetic electrons, pulse shaping hardware, a space for experimental apparatus, and a high resolution spectrometer. The leading 21 MeV pulse in a doublet can contain up to 15

R. Konecny; J. MacLachlan; J. Norem; A. Ruggiero; P. Schoessow; J. Simpson

1986-01-01

173

FXR accelerator cavity impedance experiments.  

National Technical Information Service (NTIS)

One of the goals of the present Flash X-Ray (FXR) accelerator upgrade effort (1)(2) at Lawrence Livermore National Laboratory (LLNL) is to reduce the cavity transverse impedance, since it has been shown that beam stability is significantly affected by thi...

C. A. Avalle

1998-01-01

174

Report and Accelerated and Corrosion and Studies.  

National Technical Information Service (NTIS)

Sandia National Laboratories (SNL) conducted accelerated atmospheric corrosion testing for the U.S. Consumer Product Safety Commission (CPSC) to help further the understanding of the development of corrosion products on conductor materials in household el...

C. D. Mowry N. R. Sorensen S. J. Glass

2011-01-01

175

Electrochemical Form Grinding. Fnal Report.  

National Technical Information Service (NTIS)

Electrochemical form grinding cutting tests were performed on 25 17-4 PH stainless steel bars by a copper resin aluminum oxide wheel formed from a diamond form block. Tests investigated methods of dressing a form into a grinding wheel, nozzle design, opti...

R. W. Stiles

1980-01-01

176

Electrochemical form grinding. Fnal report  

Microsoft Academic Search

Electrochemical form grinding cutting tests were performed on 25 17-4 PH stainless steel bars by a copper resin aluminum oxide wheel formed from a diamond form block. Tests investigated methods of dressing a form into a grinding wheel, nozzle design, optimum machine settings, and tolerance capabilities. The electrolyte was distributed evenly onto the wheel by a form-fitting nozzle, and a

1980-01-01

177

Pulsed Electromagnetic Acceleration of Plasma: A Review  

Microsoft Academic Search

Much have been learned about the acceleration mechanisms involved in accelerating a plasma electromagnetically in the laboratory over the last fourty years since the early review by Winston Bostik of 1963, but the accumulated understanding is very much scattered throughout the literature. This literature extends back at least to the early sixties and includes Rosenbluth's snowplow model, discussions by Ralph

Y. C. Francis Thio; Peter J. Turchi; Thomas E. Markusic; Jason T. Cassibry; James C. Sommer

2002-01-01

178

STATUS OF THE DIELECTRIC WALL ACCELERATOR  

Microsoft Academic Search

The dielectric wall accelerator (DWA) system being developed at the Lawrence Livermore National Laboratory (LLNL) uses fast switched high voltage transmission lines to generate pulsed electric fields on the inside of a high gradient insulating (HGI) acceleration tube. High electric field gradients are achieved by the use of alternating insulators and conductors and short pulse times. The system is capable

G J Caporaso; Y Chen; S Sampayan; G Akana; R Anaya; D Blackfield; J Carroll; E Cook; S Falabella; G Guethlein; J Harris; S Hawkins; B Hickman; C Holmes; A Horner; S Nelson; A Paul; D Pearson; B Poole; R Richardson; D Sanders; K Selenes; J Sullivan; L Wang; J Watson; J Weir

2009-01-01

179

Hanford as a site for large accelerators  

Microsoft Academic Search

The Ramsey Panel recommended that two very large accelerators be ;\\u000a constructed during the next few years to meet urgent U. S. needs in high energy ;\\u000a physics. Two studies have been made. The Lawrence Radiation Laboratory at ;\\u000a Berkeley has studied a 200 to 300 BeV accelerator, while the Brooknaven National ;\\u000a Laboratory on Long Island has made an

B. R. Jr

1965-01-01

180

Microgravity acceleration measurement environment characterization  

NASA Technical Reports Server (NTRS)

The Space Acceleration Measurement System (SAMS) is a general-purpose instrumentation system designed to measure the accelerations onboard the shuttle Orbiter and shuttle/Spacelab vehicles. These measurements are used to support microgravity experiments and investigations into the microgravity environment of the vehicle. Acceleration measurement can be made at locations remote from the SAMS main instrumentation unit by the use of up to three remote triaxial sensor heads. The SAMS was developed by NASA's Lewis Research Center (LeRC) in support of NASA's microgravity science programs. In the past, numerous acceleration measurement systems have flown on various space missions. These systems were tailored to measure accelerations for a narrow set of requirements and were limited in bandwidth, dynamic range, and recording capability. In addition, these systems were mission-peculiar and not easily modified for other applications or missions. The result has been an inability to accurately assess the expected microgravity environment prior to a mission for a particular experiment and/or location. The prime science objective for SAMS on the SL-J mission will be to measure the accelerations experienced by a multitude of experiments in the two racks of the Japanese First Materials Processing Test (FMPT). The FMPT consists of a variety of materials science and life science experiments contained in racks no. 7 and no. 10. The SAMS data will be made available to the FMPT principal investigators after the mission for their analysis with the FMPT data. A secondary science objective for SAMS will be the characterization of the acceleration environment of the Spacelab module. This will include an analysis of the acceleration transfer function of the Spacelab module which will utilize the FMPT acceleration measurement along with measurements at the rack no. 9 structure. Another analytical effort to be undertaken is a general characterization of the acceleration environment of the Spacelab as an orbiting laboratory. These analysis efforts will be in conjunction with similar measurements and analyses on other SAMS Spacelab missions.

Delombard, Richard

1993-01-01

181

Accelerators and the Accelerator Community  

SciTech Connect

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

Malamud, Ernest; Sessler, Andrew

2008-06-01

182

VLHC accelerator physics  

SciTech Connect

A six-month design study for a future high energy hadron collider was initiated by the Fermilab director in October 2000. The request was to study a staged approach where a large circumference tunnel is built that initially would house a low field ({approx}2 T) collider with center-of-mass energy greater than 30 TeV and a peak (initial) luminosity of 10{sup 34} cm{sup -2}s{sup -1}. The tunnel was to be scoped, however, to support a future upgrade to a center-of-mass energy greater than 150 TeV with a peak luminosity of 2 x 10{sup 34} cm{sup -2} sec{sup -1} using high field ({approx} 10 T) superconducting magnet technology. In a collaboration with Brookhaven National Laboratory and Lawrence Berkeley National Laboratory, a report of the Design Study was produced by Fermilab in June 2001. 1 The Design Study focused on a Stage 1, 20 x 20 TeV collider using a 2-in-1 transmission line magnet and leads to a Stage 2, 87.5 x 87.5 TeV collider using 10 T Nb{sub 3}Sn magnet technology. The article that follows is a compilation of accelerator physics designs and computational results which contributed to the Design Study. Many of the parameters found in this report evolved during the study, and thus slight differences between this text and the Design Study report can be found. The present text, however, presents the major accelerator physics issues of the Very Large Hadron Collider as examined by the Design Study collaboration and provides a basis for discussion and further studies of VLHC accelerator parameters and design philosophies.

Michael Blaskiewicz et al.

2001-11-01

183

Accelerator system and method of accelerating particles  

NASA Technical Reports Server (NTRS)

An accelerator system and method that utilize dust as the primary mass flux for generating thrust are provided. The accelerator system can include an accelerator capable of operating in a self-neutralizing mode and having a discharge chamber and at least one ionizer capable of charging dust particles. The system can also include a dust particle feeder that is capable of introducing the dust particles into the accelerator. By applying a pulsed positive and negative charge voltage to the accelerator, the charged dust particles can be accelerated thereby generating thrust and neutralizing the accelerator system.

Wirz, Richard E. (Inventor)

2010-01-01

184

STATUS OF THE DIELECTRIC WALL ACCELERATOR  

SciTech Connect

The dielectric wall accelerator (DWA) system being developed at the Lawrence Livermore National Laboratory (LLNL) uses fast switched high voltage transmission lines to generate pulsed electric fields on the inside of a high gradient insulating (HGI) acceleration tube. High electric field gradients are achieved by the use of alternating insulators and conductors and short pulse times. The system is capable of accelerating any charge to mass ratio particle. Applications of high gradient proton and electron versions of this accelerator will be discussed. The status of the developmental new technologies that make the compact system possible will be reviewed. These include, high gradient vacuum insulators, solid dielectric materials, photoconductive switches and compact proton sources.

Caporaso, G J; Chen, Y; Sampayan, S; Akana, G; Anaya, R; Blackfield, D; Carroll, J; Cook, E; Falabella, S; Guethlein, G; Harris, J; Hawkins, S; Hickman, B; Holmes, C; Horner, A; Nelson, S; Paul, A; Pearson, D; Poole, B; Richardson, R; Sanders, D; Selenes, K; Sullivan, J; Wang, L; Watson, J; Weir, J

2009-04-22

185

Technology of magnetically driven accelerators  

SciTech Connect

The marriage of Induction Linac technology with Nonlinear Magnetic Modulators has produced some unique capabilities. It appears possible to produce electron beams with average currents measured in amperes, at gradients exceeding 1 MeV/meter, and with power efficiencies approaching 50%. A 2 MeV, 5 kA electron accelerator has been constructed at the Lawrence Livermore National Laboratory (LLNL) to demonstrate these concepts and to provide a test facility for high brightness sources. The pulse drive for the accelerator is based on state-of-the-art magnetic pulse compressors with very high peak power capability, repetition rates exceeding a kilohertz and excellent reliability.

Brix, D.L.; Hawkins, S.A.; Poor, S.E.; Reginato, L.L.; Smith, M.W.

1985-10-01

186

Technology of magnetically driven accelerators  

SciTech Connect

The marriage of Induction Linac technology with Nonlinear Magnetic Modulators has produced some unique capabilities. It appears possible to produce electron beams with average currents measured in amperes, at gradients exceeding 1 MeV/meter, and with power efficiencies approaching 50%. A 2 MeV, 5 kA electron accelerator has been constructed at the Lawrence Livermore National Laboratory (LLNL) to demonstrate these concepts and to provide a test facility for high brightness sources. The pulse drive for the accelerator is based on state-of-the-art magnetic pulse compressors with very high peak power capability, repetition rates exceeding a kilohertz and excellent reliability. 8 figs., 1 tab.

Birx, D.L.; Hawkins, S.A.; Poor, S.E.; Reginato, L.L.; Rogers, D. Jr.; Smith, M.W.

1985-03-26

187

Argonne plasma wake-field acceleration experiments  

SciTech Connect

Four years after the initial proposal of the Plasma Wake-field Accelerator (PWFA), it continues to be the object of much investigation, due to the promise of the ultra-high accelerating gradients that can exist in relativistic plasma waves driven in the wake of charged particle beams. These wake-fields are of interest both in the laboratory, for acceleration and focusing of electrons and positrons in future linear colliders, and in nature as a possible cosmic ray acceleration mechanism. The purpose of the present work is to review the recent experimental advances made in PWFA research at Argonne National Laboratory. Some of the topics discussed are: the Argonne Advanced Accelerator Test Facility; linear plasma wake-field theory; measurement of linear plasma wake-fields; review of nonlinear plasma wave theory; and experimental measurement of nonlinear plasma wake-fields. 25 refs., 11 figs.

Rosenzweig, J.B.; Cole, B.; Gai, W.; Konecny, R.; Norem, J.; Schoessow, P.; Simpson, J.

1989-03-14

188

Accelerator Radiological Protection A Personal and Privileged Odyssey  

Microsoft Academic Search

It is not generally recognised that it was at accelerator laboratories that the foundations of the health physics profession, as we know it today, were laid. The dying years of the nineteenth century saw the birth of radiological protection. Roentgen's discovery of x-rays in 1895 with the aid of a primitive electron accelerator foreshadowed the important rôle particle-accelerators were to

Ralph H. Thomas; Marcus Tullius Cicero

189

FFAG ACCELERATOR PROTON DRIVER FOR NEUTRINO FACTORY.  

SciTech Connect

This paper is the summary of a conceptual study of a Proton Driver for Neutrino Factory based on the use of a Fixed-Field Alternating-Gradient (FFAG) Accelerator. The required proton energy range for an optimum neutrino production is 5 to 12 GeV. This can be accomplished with a group of three concentric rings each with 807 m circumference [1]. FFAG Accelerators [2] have the capability to accelerate charged particles over a large momentum range ({+-}30-50%) and the feature of constant bending and focusing fields. Particles can be accelerated very fast at the rate given by the accelerating field of RF cavities placed in proper locations between magnets. The performance of FFAG accelerators is to be placed between that of Super-Conducting Linear Accelerators (SCL), with which they share the fast acceleration rate, and Rapid-Cycling Synchrotrons (RCS), as they allow the beam to re-circulate over fewer revolutions. Brookhaven National Laboratory is involved in the study of feasibility of FFAG Accelerators to accelerate intense beams of protons in the GeV energy range for a variety of applications the most important of which is the Upgrade of the Alternating Gradient Synchrotron (AGS) with a new FFAG injector [3] accelerating from 400 MeV to 1.5 GeV. The ring would be housed in the AGS tunnel and has henceforth a circumference of 807 m.

RUGGIERO, A.

2005-06-21

190

Acceleration schedules for a recirculating heavy-ion accelerator  

SciTech Connect

Recent advances in solid-state switches have made it feasible to design programmable, high-repetition-rate pulsers for induction accelerators. These switches could lower the cost of recirculating induction accelerators, such as the ''small recirculator'' at Lawrence Livermore National Laboratory (LLNL), by substantially reducing the number of induction modules. Numerical work is reported here to determine what effects the use of fewer pulsers at higher voltage would have on the beam quality of the LLNL small recirculator. Lattices with different numbers of pulsers are examined using the fluid/envelope code CIRCE, and several schedules for acceleration and compression are compared for each configuration. For selected schedules, the phase-space dynamics is also studied using the particle-in-cell code WARP3d.

Sharp, W.M.; Grote, D.P.

2002-05-01

191

Space Radiation Effects Laboratory  

NASA Technical Reports Server (NTRS)

The SREL User's Handbook is designed to provide information needed by those who plan experiments involving the accelerators at this laboratory. Thus the Handbook will contain information on the properties of the machines, the beam parameters, the facilities and services provided for experimenters, etc. This information will be brought up to date as new equipment is added and modifications accomplished. This Handbook is influenced by the many excellent models prepared at other accelerator laboratories. In particular, the CERN Synchrocyclotron User's Handbook (November 1967) is closely followed in some sections, since the SREL Synchrocyclotron is a duplicate of the CERN machine. We wish to thank Dr. E. G. Michaelis for permission to draw so heavily on his work, particularly in Section II of this Handbook. We hope that the Handbook will prove useful, and will welcome suggestions and criticism.

1969-01-01

192

FXR accelerator cavity impedance experiments  

SciTech Connect

One of the goals of the present Flash X-Ray (FXR) accelerator upgrade effort [1][2] at Lawrence Livermore National Laboratory (LLNL) is to reduce the cavity transverse impedance, since it has been shown that beam stability is significantly affected by this parameter [3]. Recently, we have evaluated various techniques and cell modifications to accomplish that, both through lab measurements and computer models. A spare cell, identical in every way to cells in the accelerator, was specially modified for the experiments. The impedance measurements were done without the beam, by applying twin-wire techniques. This report describes the results of these experiments and suggests possible cell modifications to improve their performance. The techniques and modifications which are suggested might also be applicable to AHF and DARHT-2 long-pulse accelerator development.

Avalle, C.A.

1998-01-05

193

Argonne's Laboratory computing center - 2007 annual report  

Microsoft Academic Search

Argonne National Laboratory founded the Laboratory Computing Resource Center (LCRC) in the spring of 2002 to help meet pressing program needs for computational modeling, simulation, and analysis. The guiding mission is to provide critical computing resources that accelerate the development of high-performance computing expertise, applications, and computations to meet the Laboratory's challenging science and engineering missions. In September 2002 the

R. Bair; G. W. Pieper

2008-01-01

194

A Compact Electromagnetic Accelerator.  

National Technical Information Service (NTIS)

An electromagnetic pellet accelerator for the injection of glass beads into a plasma accelerator is used to simulate cometary dust for collection method development. The accelerator is described and a schematic diagram given. Its operational characteristi...

E. Igenbergs H. Kuczera P. Lell

1980-01-01

195

The Accelerating Universe  

SciTech Connect

From keV electrons in terrestrial aurorae to Ultra High Energy Cosmic Rays from unidentified "Zevatrons", the cosmos shows a plutocratic proclivity to concentrate energy in a tiny minority of suprathermal particles. The mechanisms involved can be traced back to the ideas of Faraday, Fermi and Alfvén though we are learning that the details are idiosyncratic to the many environments that we have observed and that much can be learned from comparing and contrasting particle acceleration in laboratory and diverse astronomical locations. It will be argued that new mechanisms are required to account for recent observations of galactic nuclei, pulsar wind nebulae and interplanetary, interstellar and intergalactic media and some candidates will be discussed.

Blandford, Roger [Stanford University

2013-05-15

196

The Accelerating Universe  

ScienceCinema

From keV electrons in terrestrial aurorae to Ultra High Energy Cosmic Rays from unidentified "Zevatrons", the cosmos shows a plutocratic proclivity to concentrate energy in a tiny minority of suprathermal particles. The mechanisms involved can be traced back to the ideas of Faraday, Fermi and Alfvén though we are learning that the details are idiosyncratic to the many environments that we have observed and that much can be learned from comparing and contrasting particle acceleration in laboratory and diverse astronomical locations. It will be argued that new mechanisms are required to account for recent observations of galactic nuclei, pulsar wind nebulae and interplanetary, interstellar and intergalactic media and some candidates will be discussed.

197

APT accelerator. Topical report  

SciTech Connect

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

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

1995-03-01

198

Muon Collider Progress: Accelerators  

SciTech Connect

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.

2011-09-10

199

International X-Band Linear Collider Accelerator Structure R&D  

SciTech Connect

For more than fifteen years before the International Technology Recommendation Panel (ITRP) decision in August, 2004, there were intensive R&D activities and broad international collaboration among the groups at SLAC, KEK, FNAL, LLNL and other labs for the room temperature X-Band accelerator structures. The goal was to provide an optimized design of the main linac structure for the NLC (Next Linear Collider) or GLC (Global Linear Collider). There have been two major challenges in developing X-band accelerator structures for the linear colliders. The first is to demonstrate stable, long-term operation at the high gradient (65 MV/m) that is required to optimize the machine cost. The second is to strongly suppress the beam induced long-range wakefields, which is required to achieve high luminosity. More than thirty X-band accelerator structures with various RF parameters, cavity shapes and coupler types have been fabricated and tested since 1989. A summary of the main achievements and experiences are presented in this talk including the structure design, manufacturing techniques, high power performance, and other structure related issues. Also, the new progress in collaborating with the CLIC, high gradient structures and X-Band structure applications for RF deflectors and others are briefly introduced.

Wang, J.W.; /SLAC

2009-03-04

200

The Gran Sasso Laboratory  

NASA Astrophysics Data System (ADS)

The Gran Sasso underground laboratory is one of the four national laboratories run by the INFN (Istituto Nazionale di Fisica Nucleare). It is located under the Gran Sasso massif, in central Italy, between the cities of L'Aquila and Teramo, 120 km far from Rome. It is the largest underground laboratory for astroparticle physics in the world and the most advanced in terms of complexity and completeness of its infrastructures. The scientific program at the Gran Sasso National Laboratories (Laboratori Nazionali del Gran Sasso, LNGS)is mainly focused on astroparticle, particle and nuclear physics. The laboratory presently hosts many experiments as well as R&D activities, including world-leading research in the fields of solar neutrinos, accelerator neutrinos (CNGS neutrino beam from CERN to Gran Sasso), dark matter, neutrinoless double-beta decay and nuclear cross-section of astrophysical interest. Associate sciences like earth physics, biology and fundamental physics complement the activities. The laboratory is operated as an international science facility and hosts experiments whose scientific merit is assessed by an international advisory Scientific Committee. A review of the main experiments carried out at LNGS will be given, together with the most recent and relevant scientific results achieved.

Votano, L.

2012-09-01

201

Inverse Free Electron Laser accelerator  

SciTech Connect

The study of the INVERSE FREE ELECTRON LASER, as a potential mode of electron acceleration, is being pursued at Brookhaven National Laboratory. Recent studies have focussed on the development of a low energy, high gradient, multi stage linear accelerator. The elementary ingredients for the IFEL interaction are the 50 MeV Linac e{sup {minus}} beam and the 10{sup 11} Watt CO{sub 2} laser beam of BNL`s Accelerator Test Facility (ATF), Center for Accelerator Physics (CAP) and a wiggler. The latter element is designed as a fast excitation unit making use of alternating stacks of Vanadium Permendur (VaP) ferromagnetic laminations, periodically interspersed with conductive, nonmagnetic laminations, which act as eddy current induced field reflectors. Wiggler parameters and field distribution data will be presented for a prototype wiggler in a constant period and in a {approximately} 1.5 %/cm tapered period configuration. The CO{sub 2} laser beam will be transported through the IFEL interaction region by means of a low loss, dielectric coated, rectangular waveguide. Short waveguide test sections have been constructed and have been tested using a low power cw CO{sub 2} laser. Preliminary results of guide attenuation and mode selectivity will be given, together with a discussion of the optical issues for the IFEL accelerator. The IFEL design is supported by the development and use of 1D and 3D simulation programs. The results of simulation computations, including also wiggler errors, for a single module accelerator and for a multi-module accelerator will be presented.

Fisher, A.; Gallardo, J.; van Steenbergen, A. [Brookhaven National Lab., Upton, NY (United States); Sandweiss, J. [Yale Univ., New Haven, CT (United States)

1992-09-01

202

Materials technology applied to nuclear accelerator targets  

NASA Astrophysics Data System (ADS)

Modification of the crystal structure of physical vapor deposited (PVD) thin films and foils by the introduction of various lamellar constituents makes possible the production of very strong, stress free, metallurgical structures. Foils <100 nm thick supported by grids 95% transparent have been produced by this technology for use as neutralizers for a neutral particle beam accelerator. Free standing, shaped, 5 ?m thick foils, sieves, and other unusual shapes were designed for electron strippers for LAMPF at Los Alamos. Unbacked cylindrical foils 0.2 ?m thick were developed for use on particle beam accelerators at Sandia National Laboratory and The Air Force Weapons Laboratory Shiva Accelerator in Albuquerque. A method of producing an ultrahigh strength Ni/Co tritium chamber for the MIT Linear Accelerator by electrodeposition which produced a lamellar structure was developed. These and other material developments will be presented in detail.

Barthell, B. L.

203

Future accelerator technology  

SciTech Connect

A general discussion is presented of the acceleration of particles. Upon this foundation is built a categorization scheme into which all accelerators can be placed. Special attention is devoted to accelerators which employ a wake-field mechanism and a restricting theorem is examined. It is shown how the theorem may be circumvented. Comments are made on various acceleration schemes.

Sessler, A.M.

1986-05-01

204

Accelerated/abbreviated test methods for predicting life of solar cell encapsulants to Jet Propulsion Laboratory California Institute of Technology for the encapsulation task of the low-cost solar array project  

NASA Technical Reports Server (NTRS)

An important principle is that encapsulants should be tested in a total array system allowing realistic interaction of components. Therefore, micromodule test specimens were fabricated with a variety of encapsulants, substrates, and types of circuitry. One common failure mode was corrosion of circuitry and solar cell metallization due to moisture penetration. Another was darkening and/or opacification of encapsulant. A test program plan was proposed. It includes multicondition accelerated exposure. Another method was hyperaccelerated photochemical exposure using a solar concentrator. It simulates 20 year of sunlight exposure in a short period of one to two weeks. The study was beneficial in identifying some cost effective encapsulants and array designs.

Kolyer, J. M.

1978-01-01

205

Development of solid-state induction modulators for high PRF accelerators  

Microsoft Academic Search

Lawrence Livermore National Laboratory (LLNL) and EG&G Energy Measurements are developing a new solid-state power system for two proposed accelerators. One of the accelerators is a circular arrangement of induction cells called a recirculator for accelerating heavy ions for inertial fusion, the other is a linear induction accelerator for electron beams called the Advanced Radiographic Machine (ARM). The need for

H. Kirbie; S. Hawkins; B. Hickman; B. Lee; M. Newton; C. Ollis; C. Brooksby; D. Gilbert; D. Longinotti; E. Eubank

1995-01-01

206

Microgravity Emissions Laboratory Developed  

NASA Technical Reports Server (NTRS)

The Microgravity Emissions Laboratory (MEL) was developed for the support, simulation, and verification of the International Space Station microgravity environment. The MEL utilizes an inertial measurement system using acceleration emissions generated by various operating components of the space station. These emissions, if too large, could hinder the science performed on the space station by disturbing the microgravity environment. Typical test components are disk drives, pumps, motors, solenoids, fans, and cameras. These components will produce inertial forces, which disturb the microgravity on-orbit station environment. These components, usually housed within a station rack, must meet acceleration limits imposed at the rack interface for minimizing the onboard station-operating environment. The NASA Glenn Research Center developed this one-of-a-kind laboratory for testing components and, eventually, rack-level configurations. The MEL approach is to measure the component's generated inertial forces. This force is a product of the full diagonal mass matrix including the test setup (the center of gravity, mass moment of inertia, and weight) and the resolved diagonal rigid-body acceleration determined from measurements using the 10 apparatus accelerometers. The mass matrix can be test derived. The bifilar torsional pendulum method is used to measure the moment of inertia for the test component.

Goodnight, Thomas W.; McNelis, Anne M.

2001-01-01

207

High-power accelerator technology and requirements  

SciTech Connect

Designs of high-power proton linear accelerators (linacs) for accelerator transmutation of waste (ATW) are being actively studied at Los Alamos National Laboratory and at several other laboratories worldwide. Beam parameters cover the 100- to 300-mA range in average current and 800 to 1600 MeV in energy. While ideas for such accelerators have been discussed for decades, the technology base has recently advanced to the point that the feasibility of machines in the ATW power class is now generally conceded. Factors contributing to this advance have been the following: experience gained with medium-power research accelerators, especially the LAMPF linac at Los Alamos; major improvements in the theory and technology of high-intensity high-brightness accelerators fostered by the SDIO Neutral Particle Beam program; and development of high-power continuous-wave (cw) radio-frequency (rf) generators for high-energy colliding-beam rings. The reference ATW accelerator concept described in this paper is based on room-temperature copper accelerating cavities. Advances in superconducting niobium cavity technology have opened the possibility of application to ATW-type linacs. Useful efficiency gains could be realized, especially for lower current systems, and there may be technical advantages as well. Technology issues that need to be addressed for superconducting rf linac designs include the development of high-power rf couplers, appropriate cavity designs, and superconducting focusing elements, as well as concerns about beam damage of niobium structures and dynamic rf control with high beam currents.

Lawrence, G.P. (Los Alamos National Lab., NM (United States))

1993-01-01

208

The Accelerator Test Facility at Brookhaven: Main capabilities  

NASA Astrophysics Data System (ADS)

Brookhaven National Laboratory's (BNL's) Accelerator Test Facility (ATF) is a user facility for accelerator- and beam- physics. Researchers from national and foreign universities, the DOE's national laboratories, and small businesses can carry out their experiments here, thereby relieving their institutions and companies from the large investment in accelerators, lasers, control and diagnostic equipment, and trained accelerator operators, all of which BNL's ATF offers. The main emphasis of this paper is on the capabilities of the ATF that I illustrate by discussing a few experiments. More detailed information can be obtained from the ATF web site: http://www.bnl.gov/atf.

Yakimenko, Vitaly

2004-12-01

209

Design of a model dipole magnet for the SSC High Energy Booster  

Microsoft Academic Search

A superconducting model dipole magnet has been designed to serve as a vehicle in an R D program to develop a dipole magnet for potential use in the SSC High Energy Booster. The objective has been to use the Brookhaven, National Laboratory (BNL) and Fermi National Accelerator Laboratory (FNAL) 50 mm aperture dipole designs to the maximum possible extent for

N. Hassan; K. Couzens; S. Dwyer; A. Jaisle; R. Jayakumar; S. Krishnamurthy; R. Mihelic; S. Phillips; R. K. Puri; K. Sarna; G. Snitchler; V. Venkatraman

1993-01-01

210

Design of a model dipole magnet for the SSC High Energy Booster  

Microsoft Academic Search

A superconducting model dipole magnet has been designed to serve as a vehicle in an R&D program to develop a dipole magnet for potential use in the SSC High Energy Booster. The objective has been to use the Brookhaven, National Laboratory (BNL) and Fermi National Accelerator Laboratory (FNAL) 50 mm aperture dipole designs to the maximum possible extent for design

N. Hassan; K. Couzens; S. Dwyer; A. Jaisle; R. Jayakumar; S. Krishnamurthy; R. Mihelic; S. Phillips; R. K. Puri; K. Sarna; G. Snitchler; V. Venkatraman

1993-01-01

211

Analysis of multilayer insulation between 80K and 300K  

SciTech Connect

A model has been developed that can be used to determine the temperature distribution and heat transfer through a multilayer insulation (MLI) blanket. Predictions from the model were compared with a series of temperature measurements made during laboratory experiments and during a test of five superconducting magnets (dipoles) installed in a string and tested at Fermi National Accelerator Laboratory, FNAL (ER Test).

Augustynowicz, S.D.; Demko, J.A. [Superconducting Super Collider Lab., Dallas, TX (United States); Datskov, V.I. [Joint Inst. for Nuclear Research, Dubna (Russian Federation). Lab. of High Energy

1993-07-01

212

Design analysis for a 100-MeV inverse Cerenkov laser accelerator.  

National Technical Information Service (NTIS)

The analysis of a 100-MeV demonstration experiment based upon inverse Cerenkov acceleration (ICA) is presented. This experiment would use the Accelerator Test Facility (ATF) at Brookhaven National Laboratory. With 50-GW of delivered laser peak power from ...

J. R. Fontana W. D. Kimura L. C. Steinhauer I. Pogorelsky

1993-01-01

213

Studies of Multipactor in Dielectric-Loaded Accelerator Structures: Comparison of Simulation Results with Experimental Data  

Microsoft Academic Search

In this paper new results of numerical studies of multipactor in dielectric-loaded accelerator structures are presented. The results are compared with experimental data obtained during recent studies of such structures performed by Argonne National Laboratory, the Naval Research Laboratory, SLAC National Accelerator Laboratory and Euclid TechLabs, LLC. Good agreement between the theory and experiment was observed for the structures with

Oleksandr Sinitsyn; Gregory Nusinovich; Thomas Jr. Antonsen

2010-01-01

214

A portable accelerator control toolkit  

SciTech Connect

In recent years, the expense of creating good control software has led to a number of collaborative efforts among laboratories to share this cost. The EPICS collaboration is a particularly successful example of this trend. More recently another collaborative effort has addressed the need for sophisticated high level software, including model driven accelerator controls. This work builds upon the CDEV (Common DEVice) software framework, which provides a generic abstraction of a control system, and maps that abstraction onto a number of site-specific control systems including EPICS, the SLAC control system, CERN/PS and others. In principle, it is now possible to create portable accelerator control applications which have no knowledge of the underlying and site-specific control system. Applications based on CDEV now provide a growing suite of tools for accelerator operations, including general purpose displays, an on-line accelerator model, beamline steering, machine status displays incorporating both hardware and model information (such as beam positions overlaid with beta functions) and more. A survey of CDEV compatible portable applications will be presented, as well as plans for future development.

Watson, W.A. III

1997-06-01

215

Thomas Jefferson National Accelerator Facility  

SciTech Connect

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

Joseph Grames, Douglas Higinbotham, Hugh Montgomery

2010-09-01

216

Accelerator Operators and Software Development  

SciTech Connect

At Thomas Jefferson National Accelerator Facility, accelerator operators perform tasks in their areas of specialization in addition to their machine operations duties. One crucial area in which operators contribute is software development. Operators with programming skills are uniquely qualified to develop certain controls applications because of their expertise in the day-to-day operation of the accelerator. Jefferson Lab is one of the few laboratories that utilizes the skills and knowledge of operators to create software that enhances machine operations. Through the programs written; by operators, Jefferson Lab has improved machine efficiency and beam availability. Because many of these applications involve automation of procedures and need graphical user interfaces, the scripting language Tcl and the Tk toolkit have been adopted. In addition to automation, some operator-developed applications are used for information distribution. For this purpose, several standard web development tools such as perl, VBScript, and ASP are used. Examples of applications written by operators include injector steering, spin angle changes, system status reports, magnet cycling routines, and quantum efficiency measurements. This paper summarizes how the unique knowledge of accelerator operators has contributed to the success of the Jefferson Lab control system. *This work was supported by the U.S. DOE contract No. DE-AC05-84-ER40150.

April Miller; Michele Joyce

2001-11-01

217

Brazing techniques for side-coupled electron accelerator structures  

SciTech Connect

The collaboration between the Los Alamos National Laboratory and the National Bureau of Standards (NBS), started in 1979, has led to the development of an advanced c-w microtron accelerator design. The four 2380-MHz NBS accelerating structures, containing a total of 184 accelerating cavities, have been fabricated and delivered. New fabrication methods, coupled with refinements of hydrogen-furnace brazing techniques described in this paper, allow efficient production of side-coupled structures. Success with the NBS RTM led to Los Alamos efforts on similar 2450-MHz accelerators for the microtron accelerator operated by the Nuclear Physics Department of the University of Illinois. Two accelerators (each with 17 cavities) have been fabricated; in 1986, a 45-cavity accelerator is being fabricated by private industry with some assistance from Los Alamos. Further private industry experience and refinement of the described fabrication techniques may allow future accelerators of this type to be completely fabricated by private industry.

Hansborough, L.D.; Clark, W.L.; DePaula, R.A.; Martinez, F.A.; Roybal, P.L.; Wilkerson, L.C.; Young, L.M.

1986-01-01

218

Brazing techniques for side-coupled electron accelerator structures  

NASA Astrophysics Data System (ADS)

The collaboration between the Los Alamos National Laboratory and the National Bureau of Standards (NBS), started in 1979, has led to the development of an advanced cw microtron accelerator design. The four 2380-MHz NBS accelerating structures, containing a total of 184 accelerating cavities, have been fabricated and delivered. New fabrication methods, coupled with refinements of hydrogen-furnace brazing techniques described in this paper, allow efficient production of side-coupled structures. Success with the NBS RTM led to Los Alamos efforts on similar 2450-MHz accelerators for the microtron accelerator operated by the Nuclear Physics Department of the University of Illinois. Two accelerators (each with 17 cavities) have been fabricated; in 1986, a 45-cavity accelerator is being fabricated by private industry with some assistance from Los Alamos. Further private industry experience and refinement of the described fabrication techniques may allow future accelerators of this type to be completely fabricated by private industry.

Hansborough, L. D.; Clark, W. L.; DePaula, R. A.; Martinez, F. A.; Roybal, P. L.; Wilkerson, L. C.; Young, L. M.

219

The Radiological Research Accelerator Facility  

SciTech Connect

The Radiological Research Accelerator Facility (RARAF) is based on a 4-MV Van de Graaff accelerator, which is used to generate a variety of well-characterized radiation beams for research in radiobiology, radiological physics, and radiation chemistry. It is part of the Center for Radiological Research (CRR) - formerly the Radiological Research Laboratory of Columbia University, and its operation is supported as a National Facility by the US Department of Energy (DOE). As such, RARAF is available to all potential users on an equal basis and scientists outside the CRR are encouraged to submit proposals for experiments at RARAF. The operation of the Van de Graaff is supported by the DOE, but the research projects themselves must be supported separately. This report provides a listing and brief description of experiments performed at RARAF during the May 1, 1992 through April 30, 1993.

Hall, E.J.; Marino, S.A.

1993-05-01

220

Archimedes: Accelerator Reveals Ancient Text  

SciTech Connect

Archimedes (287-212 BC), who is famous for shouting 'Eureka' (I found it) is considered one of the most brilliant thinkers of all times. The 10th-century parchment document known as the 'Archimedes Palimpsest' is the unique source for two of the great Greek's treatises. Some of the writings, hidden under gold forgeries, have recently been revealed at the Stanford Synchrotron Radiation Laboratory at SLAC. An intense x-ray beam produced in a particle accelerator causes the iron in original ink, which has been partly erased and covered, to send out a fluorescence glow. A detector records the signal and a digital image showing the ancient writings is produced. Please join us in this fascinating journey of a 1,000-year-old parchment from its origin in the Mediterranean city of Constantinople to a particle accelerator in Menlo Park.

Bergmann, Uwe

2004-02-24

221

Archimedes: Accelerator Reveals Ancient Text  

ScienceCinema

Archimedes (287-212 BC), who is famous for shouting 'Eureka' (I found it) is considered one of the most brilliant thinkers of all times. The 10th-century parchment document known as the 'Archimedes Palimpsest' is the unique source for two of the great Greek's treatises. Some of the writings, hidden under gold forgeries, have recently been revealed at the Stanford Synchrotron Radiation Laboratory at SLAC. An intense x-ray beam produced in a particle accelerator causes the iron in original ink, which has been partly erased and covered, to send out a fluorescence glow. A detector records the signal and a digital image showing the ancient writings is produced. Please join us in this fascinating journey of a 1,000-year-old parchment from its origin in the Mediterranean city of Constantinople to a particle accelerator in Menlo Park.

222

Improved plasma accelerator  

NASA Technical Reports Server (NTRS)

Converging, coaxial accelerator electrode configuration operates in vacuum as plasma gun. Plasma forms by periodic injections of high pressure gas that is ionized by electrical discharges. Deflagration mode of discharge provides acceleration, and converging contours of plasma gun provide focusing.

Cheng, D. Y.

1971-01-01

223

Unified accelerator libraries  

SciTech Connect

A 'Universal Accelerator Libraries' (UAL) environment is described. Its purpose is to facilitate program modularity and inter-program and inter-process communication among heterogeneous programs. The goal ultimately is to facilitate model-based control of accelerators.

Malitsky, Nikolay; Talman, Richard [Laboratory of Nuclear Studies, Cornell University, Ithaca, New York 14853 (United States)

1997-02-01

224

Applicatons of Accelerators.  

National Technical Information Service (NTIS)

The great diversity of possible applications of accelerators has been demonstrated in the past few years. Apart from the more familiar uses of accelerators for fundamental particle, nuclear, and solid state physics research, the applications range from mi...

J. S. Fraser

1979-01-01

225

Collective Acceleration of Ions.  

National Technical Information Service (NTIS)

The collective method for acceleration of ions is described. The problem of the formation of an electron ring cluster charged with ions, its stability and focusing, and some questions of acceleration are discussed. (Author)

A. B. Kuznetsov E. A. Parelshtein I. N. Ivanov K. A. R. Reshetnikov V. A. Preizendorf

1973-01-01

226

LANGUAGE LABORATORIES.  

ERIC Educational Resources Information Center

THE USE OF THE LANGUAGE LABORATORY HAS GIVEN MANY THOUSANDS OF INDIVIDUALS GOOD LISTENING AND SPEAKING PRACTICE AND HAS BECOME AN EFFECTIVE LEARNING TOOL. THE BASIC PIECE OF EQUIPMENT OF THE LANGUAGE LABORATORY IS THE TAPE RECORDER-AND-PLAYBACK, DESIGNED TO BE USED WITH AUDIOPASSIVE STUDY, AUDIOACTIVE STUDY, AUDIOACTIVE-COMPARATIVE STUDY, AND…

BRUBAKER, CHARLES WILLIAM

227

Solid state accelerator  

SciTech Connect

We present a solid state accelerator concept utilizing particle acceleration along crystal channels by longitudinal electron plasma waves in a metal. Acceleration gradients of order 100 GV/cm are theoretically possible, but channeling radiation limits the maximum attainable energy to 10/sup 5/ TeV for protons. Beam dechanneling due to multiple scattering is substantially reduced by the high acceleration gradient. Plasma wave dissipation and generation in metals are also discussed.

Chen, P.; Noble, R.J.

1987-05-05

228

A Solid state accelerator  

SciTech Connect

We present a solid state accelerator concept utilizing particle acceleration along crystal channels by longitudinal electron plasma waves in a metal. Acceleration gradients of order 100 GV/cm are theoretically possible, but channeling radiation limits the maximum attainable energy to 10/sup 5/ TeV for protons. Beam dechanneling due to multiple scattering is substantially reduced by the high acceleration gradient. Plasma wave dissipation and generation in metals are also discussed.

Chen, P.; Noble, R.J.

1986-11-06

229

Reduction of Effective Acceleration to Microgravity Levels  

NASA Technical Reports Server (NTRS)

Acceleration due to earth's gravity causes buoyancy driven convection and sedimentation in solutions. In addition. pressure gradients occur as a function of the height within a liquid column. Hence gravity effects both equilbria conditions and phase transitions as a result of hydrostatic pressure gradients. The affect of gravity on the rate of heat and man transfer in solutal processes can be particularly important in polymer processing due to the high sensitivity of polymeric materials to processing conditions. The term microgravity has been coined to describe an environment in which the affects of gravitational acceleration am greatly reduced. It may seem odd to talk in term of reducing the effects of gravitational acceleration since gravitational attraction is a basic property of matter. However, die presence of gravity on in situ processing or measurements can be negated by achieving conditions in which the laboratory, or more specifically the container of the experimental materials, a subjected to the same acceleration as the materials themselves. With regard to the laboratory reference frame, there is virtually no force on the experimental solutions. This is difficult to achieve but can be done. A short review of Newtonian physics provides an explanation on both how processes we affected by gravity and how microgravity conditions are achieved. The fact that fluids deform when subject to a force bid solids do not indicates that solids have a structure able to exert an opposing force that negates an externally applied force. Liquids deform when a force is applied, indicating that a liquid structure cannot completely negate an applied force. Just how easily a liquid resists deformation is related to its viscosity. Spaceflight provides an environment in which the laboratory reference frame i.e. the spacecraft and all the equipment therein an experiencing virtually identical forces. There is no solid foundation underneath such a laboratory, so the laboratory accelerates according to the force of gravity as do the experimental fluids within the lab. Hence, the magnitude of the form excited by the laboratory on the experimental solutions within are greatly reduced. When compared with a laboratory on the ground and averaged over time, the fluids in a spaceflight laboratory experience approximately a 10 (sup -6)decrease in acceleration relative to their laboratory reference frame hence the term microgravity.

Downey, James P.

2000-01-01

230

Accelerated test modeling  

NASA Technical Reports Server (NTRS)

Cycle life regression model, cycle life prediction model, and acceleration factors are discussed. A method was presented to: (1) select a mathematical model; (2) determine model coefficients using accelerated test data; (3) test model fit of the accelerated test data; and (4) predict normal packs.

Schwartz, D.

1978-01-01

231

Direction of Acceleration  

NSDL National Science Digital Library

In this short lab, students observe the movement of an air bubble in a small level, attached to a toy truck, as it is moved from a stop, to a steady speed and back to a stop. This gives a visual to the concepts positive acceleration, zero acceleration and negative acceleration.

Mary Spaulding, Clearbrook-Gonvick Public School, Clearbrook Minnesota, based on an original activity from Physics Principles and Problems (1995) page 75.

232

Sustained linear acceleration  

NASA Technical Reports Server (NTRS)

The subjective effects of sustained acceleration are discussed, including positive, negative, forward, backward, and lateral acceleration effects. Physiological effects, such as retinal and visual response, unconsciousness and cerebral function, pulmonary response, and renal output, are studied. Human tolerance and performance under sustained acceleration are ascertained.

Fraser, T. M.

1973-01-01

233

Angular Acceleration without Torque?  

ERIC Educational Resources Information Center

Hardly. Just as Robert Johns qualitatively describes angular acceleration by an internal force in his article "Acceleration Without Force?" here we will extend the discussion to consider angular acceleration by an internal torque. As we will see, this internal torque is due to an internal force acting at a distance from an instantaneous center.

Kaufman, Richard D.

2012-01-01

234

Prospects of High Energy Laboratory Astrophysics  

SciTech Connect

Ultra high energy cosmic rays (UHECR) have been observed but their sources and production mechanisms are yet to be understood. We envision a laboratory astrophysics program that will contribute to the understanding of cosmic accelerators with efforts to: (1) test and calibrate UHECR observational techniques, and (2) elucidate the underlying physics of cosmic acceleration through laboratory experiments and computer simulations. Innovative experiments belonging to the first category have already been done at the SLAC FFTB. Results on air fluorescence yields from the FLASH experiment are reviewed. Proposed future accelerator facilities can provided unprecedented high-energy-densities in a regime relevant to cosmic acceleration studies and accessible in a terrestrial environment for the first time. We review recent simulation studies of nonlinear plasma dynamics that could give rise to cosmic acceleration, and discuss prospects for experimental investigation of the underlying mechanisms.

Ng, J.S.T.; Chen, P.; /SLAC

2006-09-21

235

Pulsars and Acceleration Sites  

NASA Technical Reports Server (NTRS)

Rotation-powered pulsars are excellent laboratories for the studying particle acceleration as well as fundamental physics of strong gravity, strong magnetic fields and relativity. But even forty years after their discovery, we still do not understand their pulsed emission at any wavelength. I will review both the basic physics of pulsars as well as the latest developments in understanding their high-energy emission. Special and general relativistic effects play important roles in pulsar emission, from inertial frame-dragging near the stellar surface to aberration, time-of-flight and retardation of the magnetic field near the light cylinder. Understanding how these effects determine what we observe at different wavelengths is critical to unraveling the emission physics. Fortunately the Gamma-Ray Large Area Space Telescope (GLAST), with launch in May 2008 will detect many new gamma-ray pulsars and test the predictions of these models with unprecedented sensitivity and energy resolution for gamma-rays in the range of 30 MeV to 300 GeV.

Harding, Alice

2008-01-01

236

Covariant Uniform Acceleration  

NASA Astrophysics Data System (ADS)

We derive a 4D covariant Relativistic Dynamics Equation. This equation canonically extends the 3D relativistic dynamics equation , where F is the 3D force and p = m0?v is the 3D relativistic momentum. The standard 4D equation is only partially covariant. To achieve full Lorentz covariance, we replace the four-force F by a rank 2 antisymmetric tensor acting on the four-velocity. By taking this tensor to be constant, we obtain a covariant definition of uniformly accelerated motion. This solves a problem of Einstein and Planck. We compute explicit solutions for uniformly accelerated motion. The solutions are divided into four Lorentz-invariant types: null, linear, rotational, and general. For null acceleration, the worldline is cubic in the time. Linear acceleration covariantly extends 1D hyperbolic motion, while rotational acceleration covariantly extends pure rotational motion. We use Generalized Fermi-Walker transport to construct a uniformly accelerated family of inertial frames which are instantaneously comoving to a uniformly accelerated observer. We explain the connection between our approach and that of Mashhoon. We show that our solutions of uniformly accelerated motion have constant acceleration in the comoving frame. Assuming the Weak Hypothesis of Locality, we obtain local spacetime transformations from a uniformly accelerated frame K' to an inertial frame K. The spacetime transformations between two uniformly accelerated frames with the same acceleration are Lorentz. We compute the metric at an arbitrary point of a uniformly accelerated frame. We obtain velocity and acceleration transformations from a uniformly accelerated system K' to an inertial frame K. We introduce the 4D velocity, an adaptation of Horwitz and Piron s notion of "off-shell." We derive the general formula for the time dilation between accelerated clocks. We obtain a formula for the angular velocity of a uniformly accelerated object. Every rest point of K' is uniformly accelerated, and its acceleration is a function of the observer's acceleration and its position. We obtain an interpretation of the Lorentz-Abraham-Dirac equation as an acceleration transformation from K' to K.

Friedman, Yaakov; Scarr, Tzvi

2013-04-01

237

Inverse free-electron laser accelerator development.  

National Technical Information Service (NTIS)

The study of the Inverse Free-Electron Laser, as a potential mode of electron acceleration, has been pursued at Brookhaven National Laboratory for a number of years. More recent studies focused on the development of a low energy (few GeV), high gradient, ...

A. Fisher J. Gallardo A. Steenbergen J. Sandweiss J. M. Fang

1994-01-01

238

Electron acceleration in the aurora and beyond  

Microsoft Academic Search

Duncan Bryant is a retired space plasma physicist who spent most of his career at the Rutherford-Appleton Laboratory in Oxfordshire, England. For many years he has been challenging a widely accepted theory, that auroral electrons are accelerated by double layers, on the grounds that it contains a fundamental error (allegedly, an implicit assumption that charged particles can gain energy from

K. G. McClements

1999-01-01

239

Switching System for the FXR Accelerator.  

National Technical Information Service (NTIS)

A switching system has been designed for a 20 MeV flash x-ray linear induction accelerator which is being built at Lawrence Livermore Laboratory. The switching system fans out a single command pulse and amplifies it to obtain the voltage necessary for rel...

R. D. Scarpetti C. D. Parkinson

1980-01-01

240

The BNL Accelerator Test Facility control system  

SciTech Connect

Described is the VAX/CAMAC-based control system for Brookhaven National Laboratory's Accelerator Test Facility, a laser/linac research complex. Details of hardware and software configurations are presented along with experiences of using Vsystem, a commercial control system package.

Malone, R.; Bottke, I.; Fernow, R.; Ben-Zvi, I.

1993-01-01

241

LLNL Flash X-Ray Induction Linear Accelerator (FXR).  

National Technical Information Service (NTIS)

The FXR is an induction linear accelerator used for high-speed radiography at the Lawrence Livermore National Laboratorys Experimental Test Site. It was designed specifically for the radiography of very thick explosive objects. Since its completion in 198...

L. G. Multhauf

2002-01-01

242

Thermal management of an accelerator system in space.  

National Technical Information Service (NTIS)

For the past several years the Accelerator Technology Division at Los Alamos National Laboratory has been working under Strategic Defense Initiative sponsorship to develop a Neutral Particle Beam (NPB) weapon system. A weapon grade NPB system generates 10...

D. W. Reid

1990-01-01

243

High-energy lattice for first-beam operation of the SRF test accelerator at NML  

SciTech Connect

The Superconducting Radio Frequency Test Accelerator, a linear electron accelerator currently in construction at Fermilab's New Muon Laboratory, will eventually reach energies of {approx} 900 MeV using four ILC-type superconducting accelerating cryomodules. The accelerator's construction is staged according to cryomodules availability. The first phase that will support first beam operation incorporates one cryomodule. In this Note, we summarize a possible design for the first-beam accelerator configuration.

Prokop, C.; /NICADD, DeKalb; Piot, P.; /NICADD, DeKalb /Fermilab; Church, M.; /Fermilab

2011-09-01

244

Accelerator and Fusion Research Division: Summary of activities, 1986  

SciTech Connect

This report contains a summary of activities at the Lawrence Berkeley Laboratory's Accelerator and Fusion Research Division for the year 1986. Topics and facilities investigated in individual papers are: 1-2 GeV Synchrotron Radiation Source, the Center for X-Ray Optics, Accelerator Operations, High-Energy Physics Technology, Heavy-Ion Fusion Accelerator Research and Magnetic Fusion Energy. Six individual papers have been indexed separately. (LSP)

Not Available

1987-04-15

245

Brazing techniques for side-coupled electron accelerator structures  

Microsoft Academic Search

The collaboration between the Los Alamos National Laboratory and the National Bureau of Standards (NBS), started in 1979, has led to the development of an advanced c-w microtron accelerator design. The four 2380-MHz NBS accelerating structures, containing a total of 184 accelerating cavities, have been fabricated and delivered. New fabrication methods, coupled with refinements of hydrogen-furnace brazing techniques described in

L. D. Hansborough; W. L. Clark; R. A. DePaula; F. A. Martinez; P. L. Roybal; L. C. Wilkerson; L. M. Young

1986-01-01

246

New acceleration factors for temperature, humidity, bias testing  

Microsoft Academic Search

New temperature-humidity acceleration factors for surface conductance (G) were determined. These can be used to relate device life in a high-stress laboratory environment to device life in a normal-use environment. Analytical expressions for the acceleration factors were derived for both encapsulated and unencapsulated test specimens. Lower acceleration factors were predicted for specimens encapsulated with DC 3-6550 RTV silicone rubber than

N. L. Sbar; R. P. Kozakiewicz

1979-01-01

247

Industrialization of Superconducting RF Accelerator Technology  

NASA Astrophysics Data System (ADS)

Superconducting RF (SRF) accelerator technology has basically existed for 50 years. It took about 20 years to conduct basic R&D and prototyping at universities and international institutes before the first superconducting accelerators were built, with industry supplying complete accelerator cavities. In parallel, the design of large scale accelerators using SRF was done worldwide. In order to build those accelerators, industry has been involved for 30 years in building the required cavities and/or accelerator modules in time and budget. To enable industry to supply these high tech components, technology transfer was made from the laboratories in the following three regions: the Americas, Asia and Europe. As will be shown, the manufacture of the SRF cavities is normally accomplished in industry whereas the cavity testing and module assembly are not performed in industry in most cases, yet. The story of industrialization is so far a story of customized projects. Therefore a real SRF accelerator product is not yet available in this market. License agreements and technology transfer between leading SRF laboratories and industry is a powerful tool for enabling industry to manufacture SRF components or turnkey superconducting accelerator modules for other laboratories and users with few or no capabilities in SRF technology. Despite all this, the SRF accelerator market today is still a small market. The manufacture and preparation of the components require a range of specialized knowledge, as well as complex and expensive manufacturing installations like for high precision machining, electron beam welding, chemical surface preparation and class ISO4 clean room assembly. Today, the involved industry in the US and Europe comprises medium-sized companies. In Japan, some big enterprises are involved. So far, roughly 2500 SRF cavities have been built by or ordered from industry worldwide. Another substantial step might come from the International Linear Collider (ILC) project currently being designed by the international collaboration GDE (`global design effort'). If the ILC will be built, about 18,000 SRF cavities need to be manufactured worldwide within about five years. The industrialization of SRF accelerator technology is analyzed and reviewed in this article in view of the main accelerator projects of the last two to three decades.

Peiniger, Michael; Pekeler, Michael; Vogel, Hanspeter

2012-01-01

248

Notes on Laser Acceleration  

SciTech Connect

This note intends to motivate our effort toward the advent of new methods of particle acceleration, utilizing the fast rising laser technology. By illustrating the underlying principles in an intuitive manner and thus less jargon-clad fashion, we seek a direction in which we shall be able to properly control and harness the promise of laser acceleration. First we review the idea behind the laser wakefield. We then go on to examine ion acceleration by laser. We examine the sheath acceleration in particular and look for the future direction that allows orderly acceleration of ions in high energies.

Tajima, T. [Kansai Photon Science Institute and Photon Medical Research Center Japan Atomic Energy Agency Kyoto, 619-0215 (Japan)

2008-06-24

249

Compact Plasma Accelerator  

NASA Technical Reports Server (NTRS)

A plasma accelerator has been conceived for both material-processing and spacecraft-propulsion applications. This accelerator generates and accelerates ions within a very small volume. Because of its compactness, this accelerator could be nearly ideal for primary or station-keeping propulsion for spacecraft having masses between 1 and 20 kg. Because this accelerator is designed to generate beams of ions having energies between 50 and 200 eV, it could also be used for surface modification or activation of thin films.

Foster, John E.

2004-01-01

250

Power-Conditioning System for the Advanced Test Accelerator.  

National Technical Information Service (NTIS)

The Advanced Test Accelerator (ATA) is a pulsed, linear induction, electron accelerator currently under construction and nearing completion at Lawrence Livermore National Laboratory's Site 300 near Livermore, California. The ATA is a 50 MeV, 10 kA machine...

M. A. Newton M. E. Smith D. L. Birx D. R. Branum E. G. Cook

1982-01-01

251

Accelerator and Fusion Research Division 1989 summary of activities  

SciTech Connect

This report discusses the research being conducted at Lawrence Berkeley Laboratory's Accelerator and Fusion Research Division. The main topics covered are: heavy-ion fusion accelerator research; magnetic fusion energy; advanced light source; center for x-ray optics; exploratory studies; high-energy physics technology; and bevalac operations.

Not Available

1990-06-01

252

Solvent-free cleaning using a centrifugal cryogenic pellet accelerator  

Microsoft Academic Search

An advanced centrifuge that accelerates frozen COâ pellets to high speeds for surface cleaning and paint removal is being developed at the Oak Ridge National Laboratory. The centrifuge-based accelerator was designed, fabricated, and tested under a program sponsored by the Warner Robins Air Logistics Center, Robins Air Force Base, Georgia. In comparison to the more conventional compressed air ``sandblast`` pellet

J. R. Haines; P. W. Fisher; C. A. Foster

1995-01-01

253

RESEARCH ACTIVITIES RELATED TO LOW ENERGY ACCELERATORS IN CIAE  

Microsoft Academic Search

In the last a few years, several low energy accelerators were developed in China Institute of Atomic Energy (CIAE) including the different energy, electron LINACs and Cockcroft-Walton machine for high intensity deuteron beam generation. And various R&D for the proposed project, the Upgrade Project of Beijing Tandem Accelerator Laboratory were carried out, such as the ion source and injection line

Tianjue Zhang; Xialin Guan; Zhenguo Li; Jiuchang Qin; Bingfan Yang; Chengjie Chu; Baoqun Cui; Xiulong Wang; Xingdong Jiang; Shuhe Xu; Mingwu Fan; Zhixiang Zhao

254

Proceedings of the 2003 Particle Accelerator Conference  

SciTech Connect

The twentieth biennial Particle Accelerator Conference on Accelerator Science and Technology was held May 12 ? 16, 2003 at the Hilton Hotel in Portland, Oregon. The Stanford Linear Accelerator Center and the Lawrence Berkeley National Laboratory organized PAC 2003, and it was held under the auspices of the Nuclear and Plasma Sciences Society of the Institute of Electrical and Electronics Engineers and the Division of Physics of Beams of the American Physical Society. The attendance was 1025 registrants from 21 countries. The Program Committee was co-chaired by Alan Jackson and Ed Lee. The program they arranged had opening and closing plenary sessions that covered the most important accomplishments, opportunities, and applications of accelerators. During the remainder of the conference there were parallel sessions with oral and poster presentations. In addition, there was an industrial exhibit during the first three days. The Proceedings present a total of 1154 papers from the invited, contributed orals, and poster sessions.

various,

2004-03-01

255

High power RF testing of dielectric loaded accelerating structures  

Microsoft Academic Search

A joint Argonne National Laboratory\\/Naval Research Laboratory program is under way to investigate X-band dielectric-loaded accelerating (DLA) structures, using high-power 11.424-GHz radiation from the NRL Magnicon Facility. DLA structures offer the potential of a simple, inexpensive alternative to copper disk-loaded structures for use in high-gradient RF linear accelerators. The purpose of the high-power tests is to find the RF breakdown

Wei Gai; J. G. Power; R. Konecny; C. Jing; W. Liu; Z. M. Yusof; S. H. Gold; A. K. Kinkead

2004-01-01

256

High brightness electron accelerator  

DOEpatents

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

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

1994-01-01

257

Debris and micrometeorite impact measurements in the laboratory  

NASA Technical Reports Server (NTRS)

A method was developed to simulate space debris in the laboratory. This method, which is an outgrowth of research in inertial confinement fusion (ICF), uses laser ablation to accelerate material. Using this method, single 60 micron aluminum spheres were accelerated to 15 km/sec and larger 500 micron aluminum spheres were accelerated to 2 km/sec. Also, many small (less than 10 micron diameter) irregularly shaped particles were accelerated to speeds of 100 km/sec.

Resnick, J.; Grun, J.; Crawford, J.; Burris, R.; Manka, C. K.; Ford, J. L.; Ripin, B. H.

1992-01-01

258

Federal laboratories for the 21st century  

SciTech Connect

Federal laboratories have successfully filled many roles for the public; however, as the 21st Century nears it is time to rethink and reevaluate how Federal laboratories can better support the public and identify new roles for this class of publicly-owned institutions. The productivity of the Federal laboratory system can be increased by making use of public outcome metrics, by benchmarking laboratories, by deploying innovative new governance models, by partnerships of Federal laboratories with universities and companies, and by accelerating the transition of federal laboratories and the agencies that own them into learning organizations. The authors must learn how government-owned laboratories in other countries serve their public. Taiwan`s government laboratory, Industrial Technology Research Institute, has been particularly successful in promoting economic growth. It is time to stop operating Federal laboratories as monopoly institutions; therefore, competition between Federal laboratories must be promoted. Additionally, Federal laboratories capable of addressing emerging 21st century public problems must be identified and given the challenge of serving the public in innovative new ways. Increased investment in case studies of particular programs at Federal laboratories and research on the public utility of a system of Federal laboratories could lead to increased productivity of laboratories. Elimination of risk-averse Federal laboratory and agency bureaucracies would also have dramatic impact on the productivity of the Federal laboratory system. Appropriately used, the US Federal laboratory system offers the US an innovative advantage over other nations.

Gover, J. [Sandia National Labs., Albuquerque, NM (United States); Huray, P.G. [Univ. of South Carolina, Columbia, SC (United States)

1998-04-01

259

Accelerators for Inertial Fusion Energy Production  

NASA Astrophysics Data System (ADS)

Since the 1970s, high energy heavy ion accelerators have been one of the leading options for imploding and igniting targets for inertial fusion energy production. Following the energy crisis of the early 1970s, a number of people in the international accelerator community enthusiastically began working on accelerators for this application. In the last decade, there has also been significant interest in using accelerators to study high energy density physics (HEDP). Nevertheless, research on heavy ion accelerators for fusion has proceeded slowly pending demonstration of target ignition using the National Ignition Facility (NIF), a laser-based facility at Lawrence Livermore National Laboratory. A recent report of the National Research Council recommends expansion of accelerator research in the US if and when the NIF achieves ignition. Fusion target physics and the economics of commercial energy production place constraints on the design of accelerators for fusion applications. From a scientific standpoint, phase space and space charge considerations lead to the most stringent constraints. Meeting these constraints almost certainly requires the use of multiple beams of heavy ions with kinetic energies > 1 GeV. These constraints also favor the use of singly charged ions. This article discusses the constraints for both fusion and HEDP, and explains how they lead to the requirements on beam parameters. RF and induction linacs are currently the leading contenders for fusion applications. We discuss the advantages and disadvantages of both options. We also discuss the principal issues that must yet be resolved.

Bangerter, R. O.; Faltens, A.; Seidl, P. A.

2014-02-01

260

An introduction to acceleration mechanisms  

SciTech Connect

This paper discusses the acceleration of charged particles by electromagnetic fields, i.e., by fields that are produced by the motion of other charged particles driven by some power source. The mechanisms that are discussed include: Ponderamotive Forces, Acceleration, Plasma Beat Wave Acceleration, Inverse Free Electron Laser Acceleration, Inverse Cerenkov Acceleration, Gravity Acceleration, 2D Linac Acceleration and Conventional Iris Loaded Linac Structure Acceleration. (LSP)

Palmer, R.B.

1987-05-01

261

Compensation Techniques in Accelerator Physics  

SciTech Connect

Accelerator physics is one of the most diverse multidisciplinary fields of physics, wherein the dynamics of particle beams is studied. It takes more than the understanding of basic electromagnetic interactions to be able to predict the beam dynamics, and to be able to develop new techniques to produce, maintain, and deliver high quality beams for different applications. In this work, some basic theory regarding particle beam dynamics in accelerators will be presented. This basic theory, along with applying state of the art techniques in beam dynamics will be used in this dissertation to study and solve accelerator physics problems. Two problems involving compensation are studied in the context of the MEIC (Medium Energy Electron Ion Collider) project at Jefferson Laboratory. Several chromaticity (the energy dependence of the particle tune) compensation methods are evaluated numerically and deployed in a figure eight ring designed for the electrons in the collider. Furthermore, transverse coupling optics have been developed to compensate the coupling introduced by the spin rotators in the MEIC electron ring design.

Hisham Kamal Sayed

2011-05-31

262

Plasma inverse transition acceleration  

SciTech Connect

It can be proved fundamentally from the reciprocity theorem with which the electromagnetism is endowed that corresponding to each spontaneous process of radiation by a charged particle there is an inverse process which defines a unique acceleration mechanism, from Cherenkov radiation to inverse Cherenkov acceleration (ICA) [1], from Smith-Purcell radiation to inverse Smith-Purcell acceleration (ISPA) [2], and from undulator radiation to inverse undulator acceleration (IUA) [3]. There is no exception. Yet, for nearly 30 years after each of the aforementioned inverse processes has been clarified for laser acceleration, inverse transition acceleration (ITA), despite speculation [4], has remained the least understood, and above all, no practical implementation of ITA has been found, until now. Unlike all its counterparts in which phase synchronism is established one way or the other such that a particle can continuously gain energy from an acceleration wave, the ITA to be discussed here, termed plasma inverse transition acceleration (PITA), operates under fundamentally different principle. As a result, the discovery of PITA has been delayed for decades, waiting for a conceptual breakthrough in accelerator physics: the principle of alternating gradient acceleration [5, 6, 7, 8, 9, 10]. In fact, PITA was invented [7, 8] as one of several realizations of the new principle.

Xie, Ming

2001-06-18

263

Switched matrix accelerator  

SciTech Connect

We describe a new concept for a microwave circuit functioning as a charged-particle accelerator at mm wavelengths, permitting an accelerating gradient higher than conventional passive circuits can withstand consistent with cyclic fatigue. The device provides acceleration for multiple bunches in parallel channels, and permits a short exposure time for the conducting surface of the accelerating cavities. Our analysis includes scalings based on a smooth transmission line model and a complementary treatment with a coupled-cavity simulation. We also provide an electromagnetic design for the accelerating structure, arriving at rough dimensions for a seven-cell accelerator matched to standard waveguide and suitable for bench tests at low power in air at 91.392 GHz. A critical element in the concept is a fast mm-wave switch suitable for operation at high power, and we present the considerations for implementation in an H-plane tee. We discuss the use of diamond as the photoconductor switch medium.

Whittum, David H.; Tantawi, Sami G.

2001-01-01

264

THE DIELECTRIC WALL ACCELERATOR  

SciTech Connect

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

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

2009-08-17

265

Pulsed power for particle beam accelerators in military applications  

SciTech Connect

Techniques useful for generating and conditioning power for high energy pulsed accelerators with potential weapon applications are described. Pulsed electron accelerators are exemplified by ETA and ATA at Lawrence Livermore Laboratories and RADLAC at Sandia Laboratories Albuquerque. Pulse-power techniques used in other applications are briefly mentioned, including some that may be useful for collective ion accelerators. The limitations of pulse-power and the general directions of desirable development are illustrated. The main needs are to increase repetition rate and to decrease size.

Smith, I.D.

1980-06-20

266

Optically pulsed electron accelerator  

DOEpatents

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)

1987-01-01

267

Optically pulsed electron accelerator  

DOEpatents

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.

1985-05-20

268

The foxhole accelerating structure  

SciTech Connect

This report examines some properties of a new type of open accelerating structure. It consists of a series of rectangular cavities, which we call foxholes, joined by a beam channel. The power for accelerating the particles comes from an external radiation source and enters the cavities through their open upper surfaces. Analytic and computer calculations are presented showing that the foxhole is a suitable structure for accelerating relativistic electrons.

Fernow, R.C.; Claus, J.

1992-07-17

269

Resonances in accelerators  

SciTech Connect

Various resonances important in accelerators are analyzed, with the intention of demonstrating their essential similarity. Transverse instabilities of bunched electron beams are emphasized, including beam--beam effects.

Talman, R.

1987-02-25

270

Resonances in accelerators  

SciTech Connect

Various resonances important in accelerators are analyzed, with the intention of demonstrating their essential similarity. Transverse instabilities of bunched electron beams are emphasized, including beam-beam effects.

Talman, R.

1986-06-01

271

Particle acceleration in flares  

NASA Technical Reports Server (NTRS)

Particle acceleration is intrinsic to the primary energy release in the impulsive phase of solar flares, and we cannot understand flares without understanding acceleration. New observations in soft and hard X-rays, gamma-rays and coherent radio emissions are presented, suggesting flare fragmentation in time and space. X-ray and radio measurements exhibit at least five different time scales in flares. In addition, some new observations of delayed acceleration signatures are also presented. The theory of acceleration by parallel electric fields is used to model the spectral shape and evolution of hard X-rays. The possibility of the appearance of double layers is further investigated.

Benz, Arnold O.; Kosugi, Takeo; Aschwanden, Markus J.; Benka, Steve G.; Chupp, Edward L.; Enome, Shinzo; Garcia, Howard; Holman, Gordon D.; Kurt, Victoria G.; Sakao, Taro

1994-01-01

272

Accelerator-based BNCT.  

PubMed

The activity in accelerator development for accelerator-based BNCT (AB-BNCT) both worldwide and in Argentina is described. Projects in Russia, UK, Italy, Japan, Israel, and Argentina to develop AB-BNCT around different types of accelerators are briefly presented. In particular, the present status and recent progress of the Argentine project will be reviewed. The topics will cover: intense ion sources, accelerator tubes, transport of intense beams, beam diagnostics, the (9)Be(d,n) reaction as a possible neutron source, Beam Shaping Assemblies (BSA), a treatment room, and treatment planning in realistic cases. PMID:24365468

Kreiner, A J; Baldo, M; Bergueiro, J R; Cartelli, D; Castell, W; Thatar Vento, V; Gomez Asoia, J; Mercuri, D; Padulo, J; Suarez Sandin, J C; Erhardt, J; Kesque, J M; Valda, A A; Debray, M E; Somacal, H R; Igarzabal, M; Minsky, D M; Herrera, M S; Capoulat, M E; Gonzalez, S J; Del Grosso, M F; Gagetti, L; Suarez Anzorena, M; Gun, M; Carranza, O

2014-06-01

273

FFAGS FOR MUON ACCELERATION.  

SciTech Connect

Due to their finite lifetime, muons must be accelerated very rapidly. It is challenging to make the magnets ramp fast enough to accelerate in a synchrotron, and accelerating in a linac is very expensive. One can use a recirculating accelerator (like CEBAF), but one needs a different arc for each turn, and this limits the number of turns one can use to accelerate, and therefore requires significant amounts of RF to achieve the desired energy gain. An alternative method for muon acceleration is using a fixed field alternating gradient (FFAG) accelerator. Such an accelerator has a very large energy acceptance (a factor of two or three), allowing one to use the same arc with a magnetic field that is constant over time. Thus, one can in principle make as many turns as one can tolerate due to muon decay, therefore reducing the RF cost without increasing the arc cost. This paper reviews the current status of research into the design of FFAGs for muon acceleration. Several current designs are described and compared. General design considerations are also discussed.

BERG,J.S.KAHN,S.PALMER,R.TRBOJEVIC,D.JOHNSTONE,C.KEIL,Y.OGITSU,T.OHMORI,C.SESSLER,A.KOSCIELNIAK,S.

2003-06-26

274

Android Acceleration Application  

NSDL National Science Digital Library

In the first of two sequential lessons, students create mobile apps that collect data from an Android device's accelerometer and then store that data to a database. This lesson provides practice with MIT's App Inventor software and culminates with students writing their own apps for measuring acceleration. In the second lesson, students are given an app for an Android device, which measures acceleration. They investigate acceleration by collecting acceleration vs. time data using the accelerometer of a sliding Android device. Then they use the data to create velocity vs. time graphs and approximate the maximum velocity of the device.

IMPART RET Program, College of Information Science & Technology,

275

Charged particle accelerator grating  

DOEpatents

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

Palmer, Robert B. (Shoreham, NY)

1986-01-01

276

Accelerators and Nobel Laureates  

NSDL National Science Digital Library

This online article written by Sven Kullander at the Nobel e-Museum discusses the importance of particle accelerators to physics in a historical context. After studying their basic operatation, users can then learn about the many accelerator inventions and their assistance in various discoveries such as x-rays and electrons. The website provides links to descriptions of the many Nobel Prize winners who have utilized accelerators in their important work. Users can view images of the large accelerators from all over the world including the United Kingdom, Sweden, and the United State.

Kullander, Sven

277

Acceleration of polarized protons in circular accelerators  

SciTech Connect

The theory of depolarization in circular accelerators is presented. The spin equation is first expressed in terms of the particle orbit and then converted to the equivalent spinor equation. The spinor equation is then solved for three different situations: (1) a beam on a flat top near a resonance, (2) uniform acceleration through an isolated resonance, and (3) a model of a fast resonance jump. Finally, the depolarization coefficient, epsilon, is calculated in terms of properties of the particle orbit and the results are applied to a calculation of depolarization in the AGS.

Courant, E.D.; Ruth, R.D.

1980-09-12

278

The particle laser-plasma acceleration in Italy  

NASA Astrophysics Data System (ADS)

In this paper the beginning activity on Laser Plasma Acceleration in Italy and the recent results obtained in the frame of the INFN Strategic Project PLASMONX will be presented. The project, involving eight groups and two National Laboratory disseminated along Italy, is aimed at the development of an innovative, high-gradient acceleration with superintense and ultra-short laser pulses, and a tuneable, hard X/?-ray source, based upon Thomson scattering of optical photons by energetic electrons. Both experiments require very high power, ultra-short laser pulses in combination with very bright and short electron bunches generated either by conventional acceleration (LINAC) or by laser-driven acceleration in plasmas.

Giulietti, D.

2014-04-01

279

Vacuum Insulator Development for the Dielectric Wall Accelerator  

SciTech Connect

At Lawrence Livermore National Laboratory, we are developing a new type of accelerator, known as a Dielectric Wall Accelerator, in which compact pulse forming lines directly apply an accelerating field to the beam through an insulating vacuum boundary. The electrical strength of this insulator may define the maximum gradient achievable in these machines. To increase the system gradient, we are using 'High Gradient Insulators' composed of alternating layers of dielectric and metal for the vacuum insulator. In this paper, we present our recent results from experiment and simulation, including the first test of a High Gradient Insulator in a functioning Dielectric Wall Accelerator cell.

Harris, J R; Blackfield, D; Caporaso, G J; Chen, Y; Hawkins, S; Kendig, M; Poole, B; Sanders, D M; Krogh, M; Managan, J E

2008-03-17

280

Improvement of Space Shuttle Main Engine Low Frequency Acceleration Measurements  

NASA Technical Reports Server (NTRS)

The noise floor of low frequency acceleration data acquired on the Space Shuttle Main Engines is higher than desirable. Difficulties of acquiring high quality acceleration data on this engine are discussed. The approach presented in this paper for reducing the acceleration noise floor focuses on a search for an accelerometer more capable of measuring low frequency accelerations. An overview is given of the current measurement system used to acquire engine vibratory data. The severity of vibration, temperature, and moisture environments are considered. Vibratory measurements from both laboratory and rocket engine tests are presented.

Stec, Robert C.

1999-01-01

281

The Naples University 3 MV tandem accelerator  

SciTech Connect

The 3 MV tandem accelerator of the Naples University is used for research activities and applications in many fields. At the beginning of operation (1977) the main utilization was in the field of nuclear physics. Later, the realization of new beam lines allowed the development of applied activities as radiocarbon dating, ion beam analysis, biophysics, ion implantation etc. At present, the availability of different ion sources and many improvements on the accelerator allow to run experiments in a wide range of subjects. An overview of the characteristics and major activities of the laboratory is presented.

Campajola, L.; Brondi, A. [Dipartimento di Scienze Fisiche, Universita di Napoli ''Federico II'' Complesso Universitario di Monte S.Angelo via Cintia 80126 Napoli, Italy and Istituto Nazionale di Fisica Nucleare, Sez. di Napoli (Italy)

2013-07-18

282

Appalachian Laboratory  

NSDL National Science Digital Library

Located in Frostburg, Maryland, AL conducts research in aquatic ecology, landscape and watershed ecology, conservation biology and restoration ecology, behavioral and evolutionary ecology, and study both freshwater and terrestrial ecosystems of Maryland and other locations in the United States and the world. Site contains information regarding the facilities, faculty, on going research, education opportunities, and seminars. Also features information on the other UMCES laboratories.

283

Appalachian Laboratory  

NSDL National Science Digital Library

Located in Frostburg, Maryland, AL conducts research in aquatic ecology, landscape and watershed ecology, conservation biology and restoration ecology, behavioral and evolutionary ecology, and study both freshwater and terrestrial ecosystems of Maryland and other locations in the United States and the world. Site contains information regarding the facilities, faculty, on going research, education opportunities, and seminars. Also features information on the other UMCES laboratories.

2011-06-14

284

Development of X-band accelerating structures for high gradients  

Microsoft Academic Search

Short copper standing wave (SW) structures operating at an X-band frequency have been recently designed and manufactured at the Laboratori Nazionali di Frascati of the Istituto Nazionale di Fisica Nucleare (INFN) using the vacuum brazing technique. High power tests of the structures have been performed at the SLAC National Accelerator Laboratory. In this manuscript we report the results of these

S. Bini; V. Chimenti; A. Marcelli; L. Palumbo; B. Spataro; V. A. Dolgashev; S. Tantawi; A. D. Yeremian; Y. Higashi; M. G. Grimaldi; L. Romano; F. Ruffino; R. Parodi

2012-01-01

285

Low-Charge, Hard X-Ray FEL Driven with an X-Band Injector and Accelerator.  

National Technical Information Service (NTIS)

After the successful operation of FLASH (Free-Electron Laser in Hamburg) and LCLS (Linac Coherent Light Source), soft and hard X-ray Free Electron Lasers (FELs) are being built, designed or proposed at many accelerator laboratories. Acceleration employing...

C. Adolphsen C. Limborg-Deprey J. Wu T. Raubenheimer Y. Sun

2012-01-01

286

Compact Dielectric Wall Accelerator Development For Intensity Modulated Proton Therapy And Homeland Security Applications  

Microsoft Academic Search

Compact dielectric wall (DWA) accelerator technology is being developed at the Lawrence Livermore National Laboratory. The DWA accelerator uses fast switched high voltage transmission lines to generate pulsed electric fields on the inside of a high gradient insulating (HGI) acceleration tube. Its high electric field gradients are achieved by the use of alternating insulators and conductors and short pulse times.

Y-Chen; G J Caporaso; G Guethlein; S Sampayan; G Akana; R Anaya; D Blackfield; E Cook; S Falabella; E Gower; J Harris; S Hawkins; B Hickman; C Holmes; A Horner; S Nelson; A Paul; D Pearson; B Poole; R Richardson; D Sanders; J Sullivan; L Wang; J Watson; J Weir

2009-01-01

287

Understanding particle acceleration at supernova shocks  

NASA Astrophysics Data System (ADS)

One century after the pioneering discovery of cosmic rays by V. Hess, the present generation of X- and gamma-ray telescopes is finally unravelling the origin of such an extraterrestrial radiation, at least for what concerns particles with energies below ˜10^8 GeV, which are thought to be accelerated at the forward shocks of Galactic supernova remnants (SNRs). I discuss the present theoretical understanding of efficient particle acceleration at non-relativistic, collisionless shocks, addressing with both analytical and numerical (particle-in-cell) techniques the crucial interplay between accelerated ions and magnetic turbulence. In SNRs, in fact, magnetic fields turn out to be a factor of 10-100 larger than in the interstellar medium, because of plasma instabilities triggered by energetic particles. In particular, I show 2D and 3D hybrid (fluid electrons - kinetic ions) simulations of non-relativistic collisionless shocks, pointing out the efficiency of Fermi acceleration and the role of the cosmic-ray-induced filamentation instability in amplifying the magnetic field up to the levels inferred at the blast waves of young Galactic remnants. Finally, I outline the observational counterparts of such a theory of particle acceleration at strong shocks in terms of SNR multi-wavelength emission, with a special attention to Tycho's SNR, arguably the best laboratory where to test hadron acceleration.

Caprioli, Damiano

2013-04-01

288

Angular velocities, angular accelerations, and coriolis accelerations  

NASA Technical Reports Server (NTRS)

Weightlessness, rotating environment, and mathematical analysis of Coriolis acceleration is described for man's biological effective force environments. Effects on the vestibular system are summarized, including the end organs, functional neurology, and input-output relations. Ground-based studies in preparation for space missions are examined, including functional tests, provocative tests, adaptive capacity tests, simulation studies, and antimotion sickness.

Graybiel, A.

1975-01-01

289

Accelerators for energy production  

NASA Astrophysics Data System (ADS)

A tremendous progress of accelerators for these several decades, has been motivated mainly by the research on subnuclear physics. The culmination in high energy accelerators might be SSC, 20 TeV collider in USA, probably the ultimate accelerator being built with the conventional principle. The technology cultivated and integrated for the accelerator development, can now stably offer the high power beam which could be used for the energy problems. The Inertial Confinement Fusion (ICF) with high current, 10 kA and short pulse, 20 ns heavy ion beam (HIB) of mass number approximately 200, would be the most promising application of accelerators for energy production. In this scenario, the fuel containing D-T mixture, will be compressed to the high temperature, approximately 10 keV and to the high density state, approximately 1000 times the solid density with the pressure of ablative plasma or thermal X ray produced by bombarding of high power HIB. The efficiency, beam power/electric power for accelerator, and the repetition rate of HIB accelerators could be most suitable for the energy production. In the present paper, the outline of HIB ICF (HIF) is presented emphasizing the key issues of high current heavy ion accelerator system.

Katayama, Takeshi

1993-11-01

290

Induction linear accelerators  

NASA Astrophysics Data System (ADS)

Among the family of particle accelerators, the Induction Linear Accelerator is the best suited for the acceleration of high current electron beams. Because the electromagnetic radiation used to accelerate the electron beam is not stored in the cavities but is supplied by transmission lines during the beam pulse it is possible to utilize very low Q (typically<10) structures and very large beam pipes. This combination increases the beam breakup limited maximum currents to of order kiloamperes. The micropulse lengths of these machines are measured in 10's of nanoseconds and duty factors as high as 10-4 have been achieved. Until recently the major problem with these machines has been associated with the pulse power drive. Beam currents of kiloamperes and accelerating potentials of megavolts require peak power drives of gigawatts since no energy is stored in the structure. The marriage of liner accelerator technology and nonlinear magnetic compressors has produced some unique capabilities. It now appears possible to produce electron beams with average currents measured in amperes, peak currents in kiloamperes and gradients exceeding 1 MeV/meter, with power efficiencies approaching 50%. The nonlinear magnetic compression technology has replaced the spark gap drivers used on earlier accelerators with state-of-the-art all-solid-state SCR commutated compression chains. The reliability of these machines is now approaching 1010 shot MTBF. In the following paper we will briefly review the historical development of induction linear accelerators and then discuss the design considerations.

Birx, Daniel

1992-03-01

291

Unified accelerator libraries  

SciTech Connect

A {open_quotes}Universal Accelerator Libraries{close_quotes} (UAL) environment is described. Its purpose is to facilitate program modularity and inter-program and inter-process communication among heterogeneous programs. The goal ultimately is to facilitate model-based control of accelerators. {copyright} {ital 1997 American Institute of Physics.}

Malitsky, N.; Talman, R. [Laboratory of Nuclear Studies, Cornell University, Ithaca, New York 14853 (United States)

1997-02-01

292

Accelerators (3/5)  

ScienceCinema

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

2011-10-06

293

Microscale acceleration history discriminators  

DOEpatents

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)

2002-01-01

294

Accelerators Beyond The Tevatron?  

SciTech Connect

Following the successful operation of the Fermilab superconducting accelerator three new higher energy accelerators were planned. They were the UNK in the Soviet Union, the LHC in Europe, and the SSC in the United States. All were expected to start producing physics about 1995. They did not. Why?.

Lach, Joseph [Fermi National Accelerator Laboratory, P.O Box 500, Batavia Illinois (United States)

2010-07-29

295

Accelerators (5/5)  

ScienceCinema

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

2011-10-06

296

Accelerators (4/5)  

ScienceCinema

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

2011-10-06

297

Ion Induction Accelerators  

NASA Astrophysics Data System (ADS)

The description of beams in RF and induction accelerators share many common features. Likewise, there is considerable commonality between electron induction accelerators (see Chap. 7) and ion induction accelerators. However, in contrast to electron induction accelerators, there are fewer ion induction accelerators that have been operated as application-driven user facilities. Ion induction accelerators are envisioned for applications (see Chap. 10) such as Heavy Ion Fusion (HIF), High Energy Density Physics (HEDP), and spallation neutron sources. Most ion induction accelerators constructed to date have been limited scale facilities built for feasibility studies for HIF and HEDP where a large numbers of ions are required on target in short pulses. Because ions are typically non-relativistic or weakly relativistic in much of the machine, space-charge effects can be of crucial importance. This contrasts the situation with electron machines, which are usually strongly relativistic leading to weaker transverse space-charge effects and simplified longitudinal dynamics. Similarly, the bunch structure of ion induction accelerators relative to RF machines results in significant differences in the longitudinal physics.

Barnard, John J.; Horioka, Kazuhiko

298

Two-Beam Accelerator.  

National Technical Information Service (NTIS)

The Two-Beam Accelerator (TBA) consists of a long high-gradient accelerator structure (HGS) adjacent to an equal-length Free Electron Laser (FEL). In the FEL, a beam propagates through a long series of undulators. At regular intervals, waveguides couple m...

A. M. Sessler D. B. Hopkins

1986-01-01

299

Two-Beam Accelerator.  

National Technical Information Service (NTIS)

The Two-Beam Accelerator (TBA) consists of a long high-gradient accelerator structure (HGS) adjacent to an equal-length Free Electron Laser (FEL). In the FEL, a beam propagates through a long series of undulators. At regular intervals, waveguides couple m...

A. M. Sessler D. B. Hopkins

1987-01-01

300

Physics of Particle Acceleration.  

National Technical Information Service (NTIS)

The development of particle accelerators was reviewed with regard to energy and cost. The problems of funding much larger and slower particle accelerators was considered. The question of new ideas and techniques was raised and, with this in mind, the vari...

J. D. Lawson

1982-01-01

301

J-PARC Accelerator  

SciTech Connect

The Japan Proton Accelerator Research Complex (J-PARC) is under construction in Tokai site. The linac beam commissioning started last fall, while the beam commissioning of the 3-GeV Rapid-Cycling Synchrotron (RCS) will start this fall. The status of the J-PARC accelerator is reported with emphasis on the technical development accomplished for the J-PARC.

Yamazaki, Yoshishige [J-PARC Center High Energy Accelerator Research Organization (KEK) and Japan Atomic Energy Organization (JAEA) Shirakata-Shirane, Tokai-Mura, Naka-Gun, Ibaraki-Ken (Japan)

2008-02-21

302

KEK digital accelerator  

NASA Astrophysics Data System (ADS)

The High Energy Accelerator Research Organization KEK digital accelerator (KEK-DA) is a renovation of the KEK 500 MeV booster proton synchrotron, which was shut down in 2006. The existing 40 MeV drift tube linac and rf cavities have been replaced by an electron cyclotron resonance (ECR) ion source embedded in a 200 kV high-voltage terminal and induction acceleration cells, respectively. A DA is, in principle, capable of accelerating any species of ion in all possible charge states. The KEK-DA is characterized by specific accelerator components such as a permanent magnet X-band ECR ion source, a low-energy transport line, an electrostatic injection kicker, an extraction septum magnet operated in air, combined-function main magnets, and an induction acceleration system. The induction acceleration method, integrating modern pulse power technology and state-of-art digital control, is crucial for the rapid-cycle KEK-DA. The key issues of beam dynamics associated with low-energy injection of heavy ions are beam loss caused by electron capture and stripping as results of the interaction with residual gas molecules and the closed orbit distortion resulting from relatively high remanent fields in the bending magnets. Attractive applications of this accelerator in materials and biological sciences are discussed.

Iwashita, T.; Adachi, T.; Takayama, K.; Leo, K. W.; Arai, T.; Arakida, Y.; Hashimoto, M.; Kadokura, E.; Kawai, M.; Kawakubo, T.; Kubo, Tomio; Koyama, K.; Nakanishi, H.; Okazaki, K.; Okamura, K.; Someya, H.; Takagi, A.; Tokuchi, A.; Wake, M.

2011-07-01

303

Argonne's Laboratory computing resource center : 2006 annual report  

Microsoft Academic Search

Argonne National Laboratory founded the Laboratory Computing Resource Center (LCRC) in the spring of 2002 to help meet pressing program needs for computational modeling, simulation, and analysis. The guiding mission is to provide critical computing resources that accelerate the development of high-performance computing expertise, applications, and computations to meet the Laboratory's challenging science and engineering missions. In September 2002 the

R. B. Bair; D. K. Kaushik; K. R. Riley; J. V. Valdes; C. D. Drugan; G. P. Pieper

2007-01-01

304

Argonne's Laboratory Computing Resource Center : 2005 annual report  

Microsoft Academic Search

Argonne National Laboratory founded the Laboratory Computing Resource Center in the spring of 2002 to help meet pressing program needs for computational modeling, simulation, and analysis. The guiding mission is to provide critical computing resources that accelerate the development of high-performance computing expertise, applications, and computations to meet the Laboratory's challenging science and engineering missions. The first goal of the

R. B. Bair; S. C Coghlan; D. K. Kaushik; K. R. Riley; J. V. Valdes; G. P. Pieper

2007-01-01

305

Collinear wake field acceleration  

NASA Astrophysics Data System (ADS)

In the Voss-Weiland scheme of wake field acceleration a high current, ring shaped driving bunch is used to accelerate a low current beam following along an axis. In such a structure, the transformer ratio, i.e., the ratio of maximum voltage that can be gained by the on-axis beam and the voltage lost by the driving beam, can be large. In contrast, it was observed that for an arrangement in which driving and driven bunches follow the same path, and where the current distribution of both bunches is gaussian, the transformer ratio is not normally greater than two. Some of the possibilities and limitations of a collinear acceleration scheme are explored. In addition to its application to wake field acceleration in structures, this study is also of interest for the understanding of the plasma wake field accelerator.

Bane, K. I. F.; Chen, P.; Wilson, P. B.

1985-04-01

306

Collinear wake field acceleration  

SciTech Connect

In the Voss-Weiland scheme of wake field acceleration a high current, ring-shaped driving bunch is used to accelerate a low current beam following along on axis. In such a structure, the transformer ratio, i.e., the ratio of maximum voltage that can be gained by the on-axis beam and the voltage lost by the driving beam, can be large. In contrast, it has been observed that for an arrangement in which driving and driven bunches follow the same path, and where the current distribution of both bunches is gaussian, the transformer ratio is not normally greater than two. This paper explores some of the possibilities and limitations of a collinear acceleration scheme. In addition to its application to wake field acceleration in structures, this study is also of interest for the understanding of the plasma wake field accelerator. 11 refs., 4 figs.

Bane, K.L.F.; Chen, P.; Wilson, P.B.

1985-04-01

307

Laboratory directed research and development FY91  

SciTech Connect

This review of research programs at Lawrence Livermore National Laboratory is composed of individual papers on various subjects. Broad topics of interest are: chemistry and materials science, computation, earth sciences, engineering, nuclear physics, and physics, and biology. Director's initiatives include the development of a transgenic mouse, accelerator mass spectrometry, high-energy physics detectors, massive parallel computing, astronomical telescopes, the Kuwaiti oil fires and a compact torus accelerator. (GHH)

Anderson, S.E.; Hedman, I.; Kirvel, R.D.; McGregor, C.K. (eds.)

1991-01-01

308

Lunar laboratory  

SciTech Connect

An international research laboratory can be established on the Moon in the early years of the 21st Century. It can be built using the transportation system now envisioned by NASA, which includes a space station for Earth orbital logistics and orbital transfer vehicles for Earth-Moon transportation. A scientific laboratory on the Moon would permit extended surface and subsurface geological exploration; long-duration experiments defining the lunar environment and its modification by surface activity; new classes of observations in astronomy; space plasma and fundamental physics experiments; and lunar resource development. The discovery of a lunar source for propellants may reduce the cost of constructing large permanent facilities in space and enhance other space programs such as Mars exploration. 29 refs.

Keaton, P.W.; Duke, M.B.

1986-01-01

309

Centrifuge Study of Pilot Tolerance to Acceleration and the Effects of Acceleration on Pilot Performance  

NASA Technical Reports Server (NTRS)

A research program the general objective of which was to measure the effects of various sustained accelerations on the control performance of pilots, was carried out on the Aviation Medical Acceleration Laboratory centrifuge, U.S. Naval Air Development Center, Johnsville, PA. The experimental setup consisted of a flight simulator with the centrifuge in the control loop. The pilot performed his control tasks while being subjected to acceleration fields such as might be encountered by a forward-facing pilot flying an atmosphere entry vehicle. The study was divided into three phases. In one phase of the program, the pilots were subjected to a variety of sustained linear acceleration forces while controlling vehicles with several different sets of longitudinal dynamics. Here, a randomly moving target was displayed to the pilot on a cathode-ray tube. For each combination of acceleration field and vehicle dynamics, pilot tracking accuracy was measured and pilot opinion of the stability and control characteristics was recorded. Thus, information was obtained on the combined effects of complexity of control task and magnitude and direction of acceleration forces on pilot performance. These tests showed that the pilot's tracking performance deteriorated markedly at accelerations greater than about 4g when controlling a lightly damped vehicle. The tentative conclusion was also reached that regardless of the airframe dynamics involved, the pilot feels that in order to have the same level of control over the vehicle, an increase in the vehicle dynamic stability was required with increases in the magnitudes of the acceleration impressed upon the pilot. In another phase, boundaries of human tolerance of acceleration were established for acceleration fields such as might be encountered by a pilot flying an orbital vehicle. A special pilot restraint system was developed to increase human tolerance to longitudinal decelerations. The results of the tests showed that human tolerance of longitudinal deceleration forces was considerably improved through use of the special restraint system.

Creer, Brent Y.; Smedal, Harald A.; Wingrove, Rodney C.

1960-01-01

310

Eulerian measurements of horizontal accelerations in shoaling gravity waves  

NASA Technical Reports Server (NTRS)

Laboratory and field measurements of suspended sediment in the nearshore suggest that fluid accelerations are an important factor in sediment transport by oscillatory waves. Here, Eulerian accelerations of the cross-shore velocity are calculated from measurements of velocity obtained by an array of bottom-mounted electromagnetic flow meters spanning a natural surf zone. Large shoreward accelerations of brief duration are associated with the steep front faces of both near-breaking and breaking waves. Weaker offshore accelerations of longer duration occur during passage of the more gently sloped rear faces. The acceleration field is thus strongly skewed in the shoreward direction. Power spectra and bispectra indicate, as expected, that statistics of the acceleration field are significantly influenced by high-frequency motions but are rather insensitive to surf beat.

Elgar, Steve; Guza, R. T.; Freilich, M. H.

1988-01-01

311

Laboratory accreditation  

SciTech Connect

Accreditation can offer many benefits to a testing or calibration laboratory, including increased marketability of services, reduced number of outside assessments, and improved quality of services. Compared to ISO 9000 registration, the accreditation process includes a review of the entire quality system, but in addition a review of testing or calibration procedures by a technical expert and participation in proficiency testing in the areas of accreditation. Within the DOE, several facilities have recently become accredited in the area of calibration, including Sandia National Laboratories, Oak Ridge, AlliedSignal FM and T; Lockheed Martin Idaho Technologies Co., and Pacific Northwest National Lab. At the national level, a new non-profit organization was recently formed called the National Cooperation for Laboratory Accreditation (NACLA). The goal of NACLA is to develop procedures, following national and international requirements, for the recognition of competent accreditation bodies in the US. NACLA is a voluntary partnership between the public and private sectors with the goal of a test or calibration performed once and accepted world wide. The NACLA accreditation body recognition process is based on the requirements of ISO Guide 25 and Guide 58. A membership drive will begin some time this fall to solicit organizational members and an election of a permanent NACLA Board of Directors will follow later this year or early 1999.

Pettit, R.B.

1998-08-01

312

Analyzing radial acceleration with a smartphone acceleration sensor  

NASA Astrophysics Data System (ADS)

This paper continues the sequence of experiments using the acceleration sensor of smartphones (for description of the function and the use of the acceleration sensor, see Ref. 1) within this column, in this case for analyzing the radial acceleration.

Vogt, Patrik; Kuhn, Jochen

2013-03-01

313

Accelerator archeology-the resurrection of the Stanford Mark III electron linac at Duke  

Microsoft Academic Search

In the early 1960s, the Mark III accelerator at the Stanford High Energy Physics Laboratory was used as the prototype test-bed for the SLAC two-mile accelerator. In the mid 1980s, the accelerator was dismantled and a large part of it was transported to the Duke University Free-Electron Laser Laboratory to form the basis of the injector for the 1-GeV Duke

P. G. O'Shea; F. Carter; C. Dickey; N. Hower; V. N. Litvinenko; R. Sachtschale; G. Swift; P. Wang; Y. Wu; J. M. J. Madey

1995-01-01

314

Accelerator Archeology - The Resurrection of the Stanford MARKIII Electron Linac at Duke  

Microsoft Academic Search

In the early 1960s, the Mark III accelerator at the Stanford High Energy Physics Laboratory was used as the prototype test-bed for the SLAC Two-Mile accelerator. In the mid 1980s the accelerator was dismantled and a large part of it was transported to the Duke University Free-Electron Laser Laboratory to form the basis of the injector for the 1-GeV Duke

P. G. O'Shea; F. Carter; C. Dickey; N. Hower; V. N. Litvinenko; R. Sachtschale; G. Swift; P. Wang; Y. Wu; J. M. J. Madey

1996-01-01

315

Proceedings of: 2005 Particle Acceleration Confence  

SciTech Connect

The 21st Particle Accelerator Conference, PAC05, took place at the Knoxville Convention Center (KCC) from Monday through Friday, May 16-20, 2005. Sponsored by the American Physical Society (APS), the Institute of Electrics and Electronics Engineers (IEEE) with its subdivision of Nuclear and Plasma Sciences Society (NPSS), the conference was hosted by the Oak Ridge National Laboratory (ORNL) Spallation Neutron Source (SNS) Project and Thomas Jefferson National Accelerator Facility (JLab). The conference was chaired by Norbert Holtkamp, and the Local Organizing Committee was made up of staff from the ORNL SNS Project under the chairmanship of Stuart Henderson. The conference welcomed over 1400 delegates from the United States, Europe, Asia, the Middle East, South America and from as far away as Australia. Almost 1400 papers where processed during the conference and will be published on the Joint Accelerator Conferences Website (JACoW) page.

Henderson, Stuart

2006-01-01

316

Accelerator for the production of tritium (APT)  

SciTech Connect

A collaborative study by Los Alamos and Brookhaven National Laboratories, supported by the Westinghouse Hanford Company, investigating a facility to produce tritium for the nation's defense needs indicates that a 1.6-GeV, 250-mA proton accelerator is required. A reference design of this accelerator starts with two parallel 125-keV injectors feeding 350-MHz radio-frequency quadrupoles (RFQ) that funnel at 2.5 MeV into a 700-MHz drift-tube linac (DTL). The DTL injects at 100 MeV into a 1400-MHz side-coupled linac (SCL). The accelerator will cost about $1.2 B and require 746 MW of electricity. 3 refs., 3 tabs.

Wilson, M.T.; Bhatia, T.S.; Guy, F.W.; Neuschaefer, G.H.; Wangler, T.P.; Young, L.M.

1989-01-01

317

Large electrostatic accelerators  

SciTech Connect

The increasing importance of energetic heavy ion beams in the study of atomic physics, nuclear physics, and materials science has partially or wholly motivated the construction of a new generation of large electrostatic accelerators designed to operate at terminal potentials of 20 MV or above. In this paper, the author briefly discusses the status of these new accelerators and also discusses several recent technological advances which may be expected to further improve their performance. The paper is divided into four parts: (1) a discussion of the motivation for the construction of large electrostatic accelerators, (2) a description and discussion of several large electrostatic accelerators which have been recently completed or are under construction, (3) a description of several recent innovations which may be expected to improve the performance of large electrostatic accelerators in the future, and (4) a description of an innovative new large electrostatic accelerator whose construction is scheduled to begin next year. Due to time and space constraints, discussion is restricted to consideration of only tandem accelerators.

Jones, C.M.

1984-01-01

318

Accelerator Toolbox for MATLAB  

SciTech Connect

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

2001-05-29

319

Wake field acceleration  

SciTech Connect

We are investigating the possibility of accelerating particles with high gradients in a ''Wake Field Transformer'' (1,2). The progress of this experiment will be described. The development of the high current hollow beam electron gun was continued. In the conventional linac, the hollow beam was accelerated to about 6 MeV. Beam monitors came into operation, two gap monitors, two fluorescent monitors and a C-hacekerenkov monitor. Calculations with the computer code WAKTRACK(3) gave the final details for the high energy section of the accelerator that will be installed during 1986.

Bialowons, W.; Bremer, H.D.; Decker, F.h.; Hartrott, M.v.; Lewin, H.C.; Voss, G.h.; Weiland, T.; Wilhelm, P.; Chengde, X.; Yokoya, K.; and others

1987-05-05

320

NRL Compact Accelerator Theory Studies.  

National Technical Information Service (NTIS)

NRL compact accelerator theory studies in support of the Spiral Line Induction Accelerator (SLIA) and the Recirculating Linear Accelerator (RLA) are summarized in a series of short papers. The first of these papers describes the ELBA three-dimensional bea...

A. W. Ali F. Mako G. Joyce J. Krall R. F. Hubbard

1990-01-01

321

BNL ACCELERATOR TEST FACILITY CONTROL SYSTEM UPGRADE.  

SciTech Connect

Brookhaven National Laboratory's Accelerator Test Facility (ATF) has embarked on a complete upgrade of its decade old computer system. The planned improvements affect every major component: processors (Intel Pentium replaces VAXes), operating system (Linux/Real-Time Linux supplants OpenVMS), and data acquisition equipment (fast Ethernet equipment replaces CAMAC serial highway.) This paper summarizes the strategies and progress of the upgrade along with plans for future expansion.

MALONE,R.; BEN-ZVI,I.; WANG,X.; YAKIMENKO,V.

2001-06-18

322

Space Experiments with Particle Accelerators: SEPAC  

NASA Technical Reports Server (NTRS)

The Space Experiments with Particle Accelerators (SEPAC), which flew on the Atmospheric Laboratory for Applications and Science (ATLAS) 1 mission, used new techniques to study natural phenomena in the Earth's upper atmosphere, ionosphere and magnetosphere by introducing energetic perturbations into the system from a high power electron beam with known characteristics. Properties of auroras were studied by directing the electron beam into the upper atmosphere while making measurements of optical emissions. Studies were also performed of the critical ionization velocity phenomenon.

Burch, J. L.; Roberts, W. T.; Taylor, W. W. L.; Kawashima, N.; Marshall, J. A.; Moses, S. L.; Neubert, T.; Mende, S. B.; Choueiri, E. Y.

1994-01-01

323

Deuterium accelerator experiments for APT.  

SciTech Connect

Sandia National Laboratories in California initiated an experimental program to determine whether tritium retention in the tube walls and permeation through the tubes into the surrounding coolant water would be a problem for the Accelerator Production of Tritium (APT), and to find ways to mitigate the problem, if it existed. Significant holdup in the tube walls would limit the ability of APT to meet its production goals, and high levels of permeation would require a costly cleanup system for the cooling water. To simulate tritium implantation, a 200 keV accelerator was used to implant deuterium into Al 6061-T and SS3 16L samples at temperatures and particle fluxes appropriate for APT, for times varying between one week and five months. The implanted samples were characterized to determine the deuterium retention and Permeation. During the implantation, the D(d,p)T nuclear reaction was used to monitor the build-up of deuterium in the implant region of the samples. These experiments increased in sophistication, from mono-energetic deuteron implants to multi-energetic deuteron and proton implants, to more accurately reproduce the conditions expected in APT. Micron-thick copper, nickel, and anodized aluminum coatings were applied to the front surface of the samples (inside of the APT walls) in an attempt to lower retention and permeation. The reduction in both retention and permeation produced by the nickel coatings, and the ability to apply them to the inside of the APT tubes, indicate that both nickel-coated Al 6061-T6 and nickel-coated SS3 16L tubes would be effective for use in APT. The results of this work were submitted to the Accelerator Production of Tritium project in document number TPO-E29-Z-TNS-X-00050, APT-MP-01-17.

Causey, Rion A. (Sandia National Laboratories, Livermore, CA); Hertz, Kristin L. (Sandia National Laboratories, Livermore, CA); Cowgill, Donald F. (Sandia National Laboratories, Livermore, CA)

2005-08-01

324

Archimedes Laboratory  

NSDL National Science Digital Library

Proving that geometry can be more fun than a barrel of monkeys, Archimedes Laboratory is "an 'intuitive' puzzle site with fewer formulas and more visuals, which may encourage students learning this science or just constitute a platform for reflection." Probably the most strictly educational section of the site is Math to Discover, which contains discussions of the history of numbers and mathematical patterns, to name a few. Also of interest are the Puzzles to Make and Puzzles to Solve sections. Visitors can follow online instructions to create geometrical curiosities or browse a small selection of impossible object images.

325

Amps particle accelerator definition study  

NASA Technical Reports Server (NTRS)

The Particle Accelerator System of the AMPS (Atmospheric, Magnetospheric, and Plasmas in Space) payload is a series of charged particle accelerators to be flown with the Space Transportation System Shuttle on Spacelab missions. In the configuration presented, the total particle accelerator system consists of an energetic electron beam, an energetic ion accelerator, and both low voltage and high voltage plasma acceleration devices. The Orbiter is illustrated with such a particle accelerator system.

Sellen, J. M., Jr.

1975-01-01

326

Learning about Accelerated Learning.  

ERIC Educational Resources Information Center

When accelerated learning programs succeed, they do so in part because they invoke and integrate skills and basic information, theoretical understanding, and natural knowledge. The trainer must blend these elements appropriately. (JOW)

Caine, Geoffrey; Caine, Renate Nummela

1989-01-01

327

Modulational effects in accelerators.  

National Technical Information Service (NTIS)

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 diffu...

T. Satogata

1997-01-01

328

Acceleration of Logarithmic Convergence  

NASA Technical Reports Server (NTRS)

In this paper, we shall give a characterization of all monotonically decreasing sequence of positive terms, whose sum converge and then introduce a Transformation which can be used to accelerate the convergence of a large class of logarithmically convergent series.

Gaskin, J. G.; Ford, W. F.

1998-01-01

329

Accelerating Translational Research  

Cancer.gov

Accelerating Translational Research Coordinating and facilitating translational research initiatives across the NCI and the cancer research community. NCI Translational Science Meetings NCI Translates - July 28-29, 2011 NCI Translates - 2009 NCI Translates

330

ACCLIB: Accelerators as libraries  

Microsoft Academic Search

Accelerator based computing is a popular design paradigm employed by designers to help meet the power-performance requirements of modern System-on-chips (SoCs). However, the non-recurring costs (hardware design, HW\\/SW integration, logic and physical design, and mask generation) required to design SoCs have significantly increased, to the point where only very high-volume products are now able to invest in accelerator-based computing. The

Yue Du

2011-01-01

331

APT accelerator. Topical report  

Microsoft Academic Search

The Accelerator Production of Tritium (APT) project, sponsored by Department of Energy Defense Programs (DOE\\/DP), involves the preconceptual design of an accelerator system to produce tritium for the nation`s stockpile of nuclear weapons. Tritium is an isotope of hydrogen used in nuclear weapons, and must be replenished because of radioactive decay (its half-life is approximately 12 years). Because the annual

G. Lawrence; D. Rusthoi

1995-01-01

332

Rolamite acceleration sensor  

DOEpatents

A rolamite acceleration sensor which has a failsafe feature including a housing, a pair of rollers, a tension band wrapped in an S shaped fashion around the rollers, wherein the band has a force-generation cut out and a failsafe cut out or weak portion. The failsafe cut out or weak portion breaks when the sensor is subjected to an excessive acceleration so that the sensor fails in an open circuit (non-conducting) state permanently.

Abbin, Joseph P. (Albuquerque, NM); Briner, Clifton F. (Albuquerque, NM); Martin, Samuel B. (Albuquerque, NM)

1993-01-01

333

CEBAF accelerator achievements  

SciTech Connect

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

2011-06-01

334

Microgravity Acceleration Measurement System  

NASA Technical Reports Server (NTRS)

Microgravity Acceleration Measurement System (MAMS) is an ongoing study of the small forces (vibrations and accelerations) on the ISS that result from the operation of hardware, crew activities, as well as dockings and maneuvering. Results will be used to generalize the types of vibrations affecting vibration-sensitive experiments. Investigators seek to better understand the vibration environment on the space station to enable future research.

Foster, William

2009-01-01

335

Laser electron accelerator  

Microsoft Academic Search

An intense electromagnetic pulse can create weak plasma oscillations through the action of the nonlinear ponderomotive force. Electrons trapped in the wake can be accelerated to high energy. Existing glass lasers of power density 10 to the 18th W\\/sq cm shone on plasmas of densities 10 to the 18th\\/cu cm can yield gigaelectronvolts of electron energy per centimeter of acceleration

T. Tajima; J. M. Dawson

1979-01-01

336

Acceleration for the ?+?- collider  

Microsoft Academic Search

We discuss possible acceleration scenarios and methods for a ? +-?- collider. The accelerator must take the beams from ~100 MeV to 2 TeV energies within the muon life-time (2.2×10-6E?\\/m? ?S), while compressing bunches of ~1012 muons from m to cm bunch lengths. A linac, recirculating linac, and very rapid-cycling synchrotron approaches are studied. A multiple recirculating linac approach is

D. Summers; D. Neuffer; Q.-S. Shu; E. Willen

1997-01-01

337

Acceleration Disturbances onboard of Geodetic Precision Space Laboratories  

NASA Astrophysics Data System (ADS)

Bartlomiej Oszczak, b@dgps.pl University of Warmia and Mazury in Olsztyn, Poland, Olsztyn, Poland Olga Maciejczyk, omaciejczyk@gmail.com Poland In this paper there is presented the study on the parameters of the ASG-EUPOS real-time RTK service NAWGEO such as: accuracy, availability, integrity and continuity. Author's model is used for tests. These parameters enable determination of the quality of received information and practical applications of the service. Paper includes also the subject related to the NAWGEO service and algorithms used in determination of mentioned parameters. The results of accuracy and precision analyses and study on availability demonstrated that NAWGEO service enables a user a position determination with a few centimeters accuracy with high probability in any moment of time.

Peterseim, Nadja; Jakob, Flury; Schlicht, Anja

338

Laser-accelerated disks for EOS studies  

SciTech Connect

An indirect method of laser-based equation of state studies, which utilizes shock waves generated by laser-accelerated projectiles rather than ablation shocks from direct laser irradiation of the sample under investigation, is proposed and examined theoretically. We derive simple formulas for the minimum thickness and maximum speed of laser-accelerated disks, comparing them with results of Nd-laser experiments conducted by the Naval Research Laboratory. Our calculations indicate that disks can be accelerated to velocities above 10/sup 7/ cm/s using a wide choice of laser parameters (pulse duration, energy, intensity, wavelength, etc.). The use of shorter wavelengths, e.g., a KrF(0.25 ..mu..m) laser rather than Nd (1.06 ..mu..m), allows thicker disks to be accelerated and faster velocities to be attained, approximately in the ratio (lambda/sub L/(Nd)/lambda/sub L/(KrF))/sup 1/3/ approx. = 1.6. One-dimensional Lasnex computer calculations indicate that the laser-accelerated disk constitutes a useful flyer plate even while disassembling under the force of the laser ablation shock. The calculations predict that the shockwave the projectile disk generates in a second (impact) disk located a suitable distance away has a greater amplitude than the laser shock and is considerably more steady, exhibiting little decay in propagating through the second disk.

Harrach, R.J.; Szoke, A.

1981-09-01

339

Computational studies and optimization of wakefield accelerators  

SciTech Connect

Laser- and particle beam-driven plasma wakefield accelerators produce accelerating fields thousands of times higher than radio-frequency accelerators, offering compactness and ultrafast bunches to extend the frontiers of high energy physics and to enable laboratory-scale radiation sources. Large-scale kinetic simulations provide essential understanding of accelerator physics to advance beam performance and stability and show and predict the physics behind recent demonstration of narrow energy spread bunches. Benchmarking between codes is establishing validity of the models used and, by testing new reduced models, is extending the reach of simulations to cover upcoming meter-scale multi-GeV experiments. This includes new models that exploit Lorentz boosted simulation frames to speed calculations. Simulations of experiments showed that recently demonstrated plasma gradient injection of electrons can be used as an injector to increase beam quality by orders of magnitude. Simulations are now also modeling accelerator stages of tens of GeV, staging of modules, and new positron sources to design next-generation experiments and to use in applications in high energy physics and light sources.

Tsung, Frank S.; Bruhwiler, David L.; Cary, John R.; Esarey, Eric H.; Mori, Warren B.; Vay, Jean-Luc; Martins, Samuel F.; Katsouleas, Tom; Cormier-Michel, Estelle; Fawley, William M.; Huang, Chengkun; Wang, Xiadong; Cowan, Ben; Decyk, Victor K.; Fonseca, Ricardo A.; Lu, Wei; Messmer, Peter; Mullowney, Paul; Nakamura, Kei; Paul, Kevin; Plateau, Guillaume R.; Schroeder, Carl B.; Silva, Luis O.; Toth, Csaba; Geddes, C.G.R.; Tzoufras, Michael; Antonsen, Tom; Vieira, Jorge; Leemans, Wim P.

2008-06-16

340

High Quality Electron Beams from Laser Accelerators  

NASA Astrophysics Data System (ADS)

Twenty five years ago, laser driven accelerators were proposed as an alternative to conventional accelerator systems.[1] The appeal was and is the large accelerating gradients (up to hundreds of GV/m) that can allow the development of compact devices capable of producing multi-GeV electron beams. Until recently, all experiments produced large gradients but beams with 100 % energy spread and only a small amount of electrons at high energy. This has recently changed. At the multi-beam L'OASIS facility at LBNL we have produced beams with narrow energy spread using a channel guided laser accelerator.[2] At Rutherford Appleton Laboratories (UK)[3] and at the Ecole Polytechnique (France),[4] beams with narrow energy spread were produced by using laser beams with relatively large focal spots. These results demonstrate that laser-plasma based accelerator can produce high quality electron beams. A review of the L'OASIS experiments will be presented as well as our plans and activities for producing a GeV-class electron beam. [1] T. Tajima and J.M. Dawson, Phys. Rev. Lett. 43, 267-270 (1979). [2] C.G.R. Geddes et al., Nature 431, 538- 541(2004). [3] S.P.D. Mangles et al., Nature 431, 535 --538 (2004). [4] J. Faure et al., Nature 431, 541-544 (2004).

Leemans, Wim

2005-04-01

341

Stone Preservatives: Methods of Laboratory Testing and Preliminary Performance Criteria.  

National Technical Information Service (NTIS)

Although numerous materials have been proposed as preservatives for stone in historic buildings and monuments, their efficacy is difficult to establish. A laboratory research program of accelerated simulated stone decay was used to obtain data on stone pr...

G. A. Sleater

1977-01-01

342

RF Superconductivity Research and Development at Los Alamos National Laboratory.  

National Technical Information Service (NTIS)

Los Alamos National Laboratory is engaged in two distinct areas of rf superconductivity research and development. One program is devoted to studying the rf properties of high-temperature superconductors (HTS) and assessing their potential for accelerator-...

D. W. Cooke E. R. Gray R. J. Houlton G. P. Lawrence J. A. McGill

1989-01-01

343

FSL in Review, 2004, Forest Systems Laboratory, Boulder, Colorado.  

National Technical Information Service (NTIS)

The mission of the Forecast Systems Laboratory is transferring advances in science and technology to the nations operational weather services. To keep pace with accelerating technological change, FSL has also changed its efforts to anticipate the needs of...

2005-01-01

344

Laboratory investigations  

NASA Technical Reports Server (NTRS)

Laboratory studies related to cometary grains and the nuclei of comets can be broken down into three areas which relate to understanding the spectral properties, the formation mechanisms, and the evolution of grains and nuclei: (1) Spectral studies to be used in the interpretation of cometary spectra; (2) Sample preparation experiments which may shed light on the physical nature and history of cometary grains and nuclei by exploring the effects on grain emissivities resulting from the ways in which the samples are created; and (3) Grain processing experiments which should provide insight on the interaction of cometary grains with the environment in the immediate vicinity of the cometary nucleus as the comet travels from the Oort cloud through perihelion, and perhaps even suggestions regarding the relationship between interstellar grains and cometary matter. A summary is presented with a different view of lab experiments than is found in the literature, concentrating on measurement techniques and sample preparations especially relevant to cometary dust.

Russell, Ray W.

1988-01-01

345

Virtual Laboratory  

NSDL National Science Digital Library

The website for the Virtual Laboratory contains a bold and direct statement: "Conventional teaching all too often accepts memorization and pattern recognition as true learning" After reading this statement, it makes sense that the goal of this site is "to help students to recognize, confront, correct, and expand their understanding of subject or a technique." The site contains five different sets of course materials that use interactive materials, short quizzes, and embedded demonstrations to assist students and teachers alike. One set of materials that should not be missed is in the Teaching & Learning Biology area. Here visitors will find links, fact sheets, and pedagogical suggestions for teaching a college-level biology course. Moving on, the Chemistry, Life, the Universe and Everything section contains a new perspective on how to reform the garden-variety general chemistry course.

2012-04-30

346

Laboratory Simulations  

NASA Astrophysics Data System (ADS)

Geophysical properties of near-Earth objects (NEOs) can best be studied using radio tomography and seismology. Reflection and transmission radio tomography is best suited for measuring the complex electric permittivity of poorly conducting materials to reveal the internal structure of NEOs. Such NEOs are primarily comet nuclei and carbonaceous asteroids. Seismic experiments are most suitable for studying elastic properties of consolidated materials to reveal material strengths of stony and iron-nickel asteroids. Thus, the two methods are complementary for investigating comets and asteroids of all types. Analysis of reflection and transmission radio tomography of heterogeneous irregular shaped bodies is very difficult. Scattering by internal and outer boundaries, differences in the refractive indices of heterogeneous materials, and attenuation by electric conductivity complicate the analyses. For this reason laboratory simulations with scaled objects and scaled wavelengths is extremely useful to check the reliability of inversion techniques of radio signals to arrive at the interior structure of an NEO. Another approach to obtaining quantitative information on the composition and structure of an NEO is through induced seismology. There are two approaches to producing seismic waves: small explosive charges and impactors. Experimental work has been performed in the laboratory to examine the impulse delivered by explosives. Wave travel times can be used to back out basic material properties and first order structure of an NEO. For example, if distinct arrival pulses for P and S waves are recorded and the explosive initiation/impact time and location are known, then it is possible to determine the elastic properties of bulk and shear modulus. Reflections in the seismograms allow a determination of material boundaries in an NEO. Original arrival time is important since Q numbers for stony NEO material are presumed to be high, as they were on the Moon, and thus it is expected that there will be extensive ringing and noise. Other types of NEO materials will have differing seismic characteristics.

Huebner, W. F.; Walker, J.; Gustafson, B.

347

DIANA - An Underground Accelerator Facility for Nuclear Astrophysics  

NASA Astrophysics Data System (ADS)

Measuring nuclear reactions of astrophysical interest at stellar energies is usually a daunting task because the cross sections are very small and background rates can be comparatively large. Often, cosmic-ray interactions set the limit on experimental sensitivity, but can be reduced to an insignificant level by placing an accelerator underground -- as has been demonstrated by the LUNA accelerators in the Gran Sasso underground laboratory. The Dual Ion Accelerator facility for Nuclear Astrophysics (DIANA) is a proposed next-generation underground accelerator facility, which would be constructed at the 4850 ft level of the Homestake Mine in Lead, SD. This talk will describe DIANA and the questions in nuclear astrophysics that can be explored at such a laboratory.

Champagne, Arthur

2011-10-01

348

Laboratory of Nuclear Studies (Osako University, Japan). Annual Report, 1982.  

National Technical Information Service (NTIS)

The major accelerators of the Osaka University Laboratory of Nuclear Studies (OULNS) are the variable energy cyclotron that can run up to 28 MeV and the 5 MeV Van de Graaff accelerator. Works of nuclear physics have been performed by means of the inbeam e...

1982-01-01

349

Impulsive acceleration of strongly magnetized relativistic flows  

NASA Astrophysics Data System (ADS)

The strong variability of magnetic central engines of active galactic nuclei (AGNs) and gamma-ray bursts (GRBs) may result in highly intermittent strongly magnetized relativistic outflows. We find a new magnetic acceleration mechanism for such impulsive flows that can be much more effective than the acceleration of steady-state flows. This impulsive acceleration results in kinetic-energy-dominated flows that are conducive to efficient dissipation at internal magnetohydrodynamic shocks on astrophysically relevant distances from the central source. For a spherical flow, a discrete shell ejected from the source over a time t0 with Lorentz factor ?˜ 1 and initial magnetization ?0=B20/4??0c2? 1 quickly reaches a typical Lorentz factor ?˜?1/30 and magnetization ?˜?2/30 at the distance R0?ct0. At this point, the magnetized shell of width ?˜R0 in the laboratory frame loses causal contact with the source and continues to accelerate by spreading significantly in its own rest frame. The expansion is driven by the magnetic pressure gradient and leads to relativistic relative velocities between the front and back of the shell. While the expansion is roughly symmetric in the centre of the momentum frame, in the laboratory frame, most of the energy and momentum remains in a region (or shell) of width ?˜R0 at the head of the flow. This acceleration proceeds as ?˜ (?0R/R0)1/3 and ?˜?2/30 (R/R0)-1/3 until reaching a coasting radius Rc˜R0?20, where the kinetic energy becomes dominant: ?˜?0 and ?˜ 1 at Rc. The shell then starts coasting and spreading (radially), its width growing as ?˜R0(R/Rc), causing its magnetization to drop as ?˜Rc/R at R > Rc. Given the typical variability time-scales of AGNs and GRBs, the magnetic acceleration in these sources is a combination of the quasi-steady-state collimation acceleration close to the source and the impulsive (conical or locally quasi-spherical) acceleration farther out. The interaction with the external medium, which can significantly affect the dynamics, is briefly addressed in the discussion.

Granot, Jonathan; Komissarov, Serguei S.; Spitkovsky, Anatoly

2011-02-01

350

Superconducting Accelerator Structures: An Historical Overview  

NASA Astrophysics Data System (ADS)

In 1961 I began doing active research on RF superconducting cavities at the High Energy Physics Laboratory (HEPL) at Stanford University. At that time there were already nascent research programs exploring superconducting cavities at four other laboratories around the world, including the one at the Stanford physics department. However, all attempts to produce a substantial accelerating field in a superconducting cavity had failed. Since a cavity that is capable of acceleration always has a surface electric field, I decided that my first research effort would be to build and test a cavity with only a magnetic field at the surface. The frequency would need to be 2856 MHz, that of the electron linac at HEPL, so that available instrumentation could be used. In order to have only a magnetic field at the surface, the cavity would have to operate in the so-called TE mode. But there was a problem: at 2856 MHz such a cavity would be considerably larger than the single-cell accelerating mode cavities previously built at the Stanford physics department. In collaboration with the low temperature physics group in the Stanford physics department, a larger electroplating facility was built that was capable of handling the cylindrical cavity body and two end plates. The initial measurements gave stunning results: a Q factor of about 10^8 at 4 K for a lead-plated cavity was obtained, and there was no degradation in Q up to a surface magnetic field of about 10 mT, (limited by the oscillator power). The results were published in 1963. Experimentation on superconducting accelerator cavities increased rapidly in the decade or so following this initial success. Successful niobium TM-mode (accelerating mode) cavities were built with Q's of about 10^11. Within a few years the multipactor problem in accelerating cavities was solved by changing the shape of the outer boundary. The initial impetus for superconducting accelerator research at Stanford was to design and build a long pulse superconducting linac with an energy of about one GeV. Such a linac has still not been realized, but in the years from 1970 to 1990 there have been successful applications of RF superconducting structures to storage rings, rf separators, drive linacs for FEL's, and heavy ion accelerators. The evolution superconducting structures and their applications, as outlined above, will be discussed in more detail in my talk

Wilson, Perry

2011-03-01

351

Development of a sealed-accelerator-tube neutron generator  

Microsoft Academic Search

Sealed-accelerator-tube neutron generators are being developed in Lawrence Berkeley National Laboratory (LBNL) for applications ranging from neutron radiography to boron neutron capture therapy and neutron activation analysis. The new generation of high-output neutron generators is based on the D–T fusion reaction, producing 14.1-MeV neutrons. The main components of the neutron tube — the ion source, the accelerator and the target

J. M. Verbeke; K. N. Leung; J. Vujic

2000-01-01

352

Microgravity Acceleration Measurement System for the International Space Station  

Microsoft Academic Search

The Microgravity Acceleration Measurement System (MAMS) is a high resolution and wide dynamic range dual sensor-based accelerometry instrumentation system to be installed within the International Space Station's (ISS) US Laboratory Module. The MAMS instrument will provide highly accurate acceleration measurement data over the nano-g to milli-g range characterizing the Lab Module environment in the frequency spectrum from 10-4 Hz to

James E. Rice; James C. Fox; William G. Lange; Robert W. Dietrich; W. O. Wagar

1999-01-01

353

Accelerator-based Neutron Sources  

Microsoft Academic Search

Since the earliest experiments defining the properties of the neutron, accelerators have played an important role in providing neutrons for research and applications. For many years, neutrons produced at accelerator facilities have complemented capabilities available from reactor-based sources. Now, with the declining availability of reactor facilities, upgrades of existing accelerator facilities and proposed new, more powerful accelerator-based sources will be

James B. Ball

1997-01-01

354

Plasma-based accelerator structures  

SciTech Connect

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

Schroeder, Carl B.

1999-12-01

355

Linear induction accelerators  

SciTech Connect

The development of linear induction accelerators has been motivated by applications requiring high-pulsed currents of charged particles at voltages exceeding the capability of single-stage, diode-type accelerators and at currents too high for rf accelerators. In principle, one can accelerate charged particles to arbitrarily high voltages using a multi-stage induction machine, but the 50-MeV, 10-kA Advanced Test Accelerator (ATA) at LLNL is the highest voltage machine in existence at this time. The advent of magnetic pulse power systems makes sustained operation at high-repetition rates practical, and this capability for high-average power is very likely to open up many new applications of induction machines in the future. This paper surveys the US induction linac technology with primary emphasis on electron machines. A simplified description of how induction machines couple energy to the electron beam is given, to illustrate many of the general issues that bound the design space of induction linacs.

Briggs, R.J.

1986-06-01

356

Advanced accelerator theory development  

SciTech Connect

A new accelerator technology, the dielectric wall accelerator (DWA), is potentially an ultra compact accelerator/pulsed power driver. This new accelerator relies on three new components: the ultra-high gradient insulator, the asymmetric Blumlein and low jitter switches. In this report, we focused our attention on the first two components of the DWA system the insulators and the asymmetric Blumlein. First, we sought to develop the necessary design tools to model and scale the behavior of the high gradient insulator. To perform this task we concentrated on modeling the discharge processes (i.e., initiation and creation of the surface discharge). In addition, because these high gradient structures exhibit favorable microwave properties in certain accelerator configurations, we performed experiments and calculations to determine the relevant electromagnetic properties. Second, we performed circuit modeling to understand energy coupling to dynamic loads by the asymmetric Blumlein. Further, we have experimentally observed a non-linear coupling effect in certain asymmetric Blumlein configurations. That is, as these structures are stacked into a complete module, the output voltage does not sum linearly and a lower than expected output voltage results. Although we solved this effect experimentally, we performed calculations to understand this effect more fully to allow better optimization of this DWA pulse-forming line system.

Sampayan, S.E.; Houck, T.L.; Poole, B.; Tishchenko, N.; Vitello, P.A.; Wang, I.

1998-02-09

357

Heparin Accelerates Gelsolin Amyloidogenesis†  

PubMed Central

The chemical environment of the extracellular matrix may influence the tissue-selective deposition observed there in gelsolin amyloid disease. Previously, we have identified the proteases that generate the amyloidogenic fragments from the full length gelsolin variants, and demonstrated that heparin is capable of accelerating gelsolin amyloidogenesis. Herein, we identify the structural features of heparin that promote the 8 kDa disease-associated gelsolin fragments (residues 173-243) generated at the cell surface to form amyloid. In conjunction with electron microscopy analyses, our kinetic studies demonstrate that heparin efficiently accelerates the formation of gelsolin amyloid by enabling intermolecular ?-sheet formation. The use of heparin analogues reveal that sulfation is important in accelerating amyloidogenesis and that the extent of acceleration is proportional to the molecular weight of heparin. In addition, heparin accelerated aggregation at both early and late stages of amyloidogenesis. Dynamic light scattering coupled to size exclusion chromatography showed that heparin promotes the formation of soluble aggregates. Collectively, these data reveal that heparin templates fibril formation and affords solubility to the aggregating peptides through its sulfated structure. By extension, the biochemical results herein suggest that tissue-selective deposition characteristic of the gelsolin amyloidoses are likely influenced by the extracellular localization of distinct glycosaminoglycans.

Suk, Ji Young; Zhang, Fuming; Balch, William E.; Linhardt, Robert J.; Kelly, Jeffery W.

2009-01-01

358

Laser acceleration with open waveguides  

SciTech Connect

A unified framework based on solid-state open waveguides is developed to overcome all three major limitations on acceleration distance and hence on the feasibility of two classes of laser acceleration. The three limitations are due to laser diffraction, acceleration phase slippage, and damage of waveguide structure by high power laser. The two classes of laser acceleration are direct-field acceleration and ponderomotive-driven acceleration. Thus the solutions provided here encompass all mainstream approaches for laser acceleration, either in vacuum, gases or plasmas.

Xie, Ming

1999-03-01

359

Heavy Ion Fusion Accelerator Research (HIFAR) year-end report, April 1, 1990--September 30, 1990  

SciTech Connect

The basic objective of the Heavy Ion Fusion Accelerator Research (HIFAR) program is to assess the suitability of heavy ion accelerators as igniters for Inertial Confinement Fusion (ICF). A specific accelerator technology, induction acceleration, is being studied at the Lawrence Berkeley Laboratory and at the Lawrence Livermore National Laboratory. The HIFAR program addresses the generation of high-power, high-brightness beams of heavy ions, the understanding of the scaling laws in this novel physics regime, and the validation of new accelerator strategies to cut costs. Key elements to be addressed include: (1) beam quality limits set by transverse and longitudinal beam physics; (2) development of induction accelerating modules, and multiple-beam hardware, at affordable costs; (3) acceleration of multiple beams with current amplification without significant dilution of the optical quality of the beams; (4) final bunching, transport, and accurate focusing on a small target.

Not Available

1990-12-01

360

Amebiasis: Laboratory Diagnosis. Part III. Laboratory Procedures.  

National Technical Information Service (NTIS)

Study program designed for individual instruction. The lesson presents diagnostic characteristics of the various species of intestinal amoeba and the laboratory methods used for laboratory examinations.

M. M. Brooke R. K. Carver D. M. Melvin R. L. Reynolds J. H. Harless

1976-01-01

361

Protecting proton beam piping at Fermi Laboratory  

SciTech Connect

Bare steel, high-energy particle beam piping was cathodically protected without interfering with delicate instrumentation and operation of the Fermi Nuclear Accelerator Laboratory. The paper describes the site, and discusses design concerns, including grounding, electrical continuity, instrumentation, shielding, interference with other structures, and environmental safety. Initial evaluations, design concepts, and installation are discussed.

Fitzgerald, J.H. III [PSG Corrosion Engineering/CorrPro Inc., Grosse Pointe Park, MI (United States)

1996-03-01

362

Laboratory directed research and development FY91  

Microsoft Academic Search

This review of research programs at Lawrence Livermore National Laboratory is composed of individual papers on various subjects. Broad topics of interest are: chemistry and materials science, computation, earth sciences, engineering, nuclear physics, and physics, and biology. Director's initiatives include the development of a transgenic mouse, accelerator mass spectrometry, high-energy physics detectors, massive parallel computing, astronomical telescopes, the Kuwaiti oil

S. E. Anderson; I. Hedman; R. D. Kirvel; C. K. McGregor

1991-01-01

363

Lawrence Berkeley Laboratory catalog of research projects  

SciTech Connect

Research from Lawrence Berkeley Laboratory is briefly presented. Topics include: (1) Applied Science; (2) Chemical Sciences; (3) Earth Sciences; (4) Materials Sciences; (5) Accelerator and Fusion Research; (6) Nuclear Science; (7) Physics; (8) Cell and Molecular Biology; (9) Chemical Biodynamics; (10) Research Medicine and Radiation Biophysics; (11) Engineering; (12) Environmental Protection, Health and Safety; and (13) Information and Computing Sciences. (WET)

Not Available

1991-01-01

364

Medical uses of accelerators  

SciTech Connect

A variety of particle accelerators have either potential or already demonstrated uses in connection with medically-related research, diagnosis, and treatment. For cancer radiotherapy, nuclear particles including protons, neutrons, heavy ions, and negative pi mesons have advantages compared to conventional radiations in terms of dose localization and/or biological effectiveness. Clinical evaluations of these particles are underway at a number of institutions. Accelerator-produced radionuclides are in widespread use for research and routine diagnostic purposes. Elemental analysis techniques with charged particles and neutrons are being applied to bone, blood, and other tissues. Finally, low-dose medical imaging can be accomplished with accelerated protons and heavy ions. The status and future of these programs are discussed.

Bradbury, J.N.

1981-01-01

365

Miniature penetrator (MinPen) acceleration recorder development test  

SciTech Connect

The Telemetry Technology Development Department at Sandia National Laboratories actively develops and tests acceleration recorders for penetrating weapons. This new acceleration recorder (MinPen) utilizes a microprocessor-based architecture for operational flexibility while maintaining electronics and packaging techniques developed over years of penetrator testing. MinPen has been demonstrated to function in shock environments up to 20,000 Gs. The MinPen instrumentation development has resulted in a rugged, versatile, miniature acceleration recorder and is a valuable tool for penetrator testing in a wide range of applications.

Franco, R.J.; Platzbecker, M.R.

1998-08-01

366

High transformer ratio drive beams for wakefield accelerator studies  

NASA Astrophysics Data System (ADS)

For wakefield based acceleration schemes, use of an asymmetric (or linearly ramped) drive bunch current profile has been predicted to enhance the transformer ratio and generate large accelerating wakes. We discuss plans and initial results for producing such bunches using the 20 to 23 GeV electron beam at the FACET facility at SLAC National Accelerator Laboratory and sending them through plasmas and dielectric tubes to generate transformer ratios greater than 2 (the limit for symmetric bunches). The scheme proposed utilizes the final FACET chicane compressor and transverse collimation to shape the longitudinal phase space of the beam.

England, R. J.; Ng, C.-K.; Frederico, J.; Hogan, M. J.; Litos, M.; Muggli, P.; Joshi, C.; An, W.; Andonian, G.; Mori, W.; Lu, W.

2012-12-01

367

Design of a dedicated heavy ion accelerator for radiotherapy  

SciTech Connect

A new heavy-ion accelerator facility for radiotherapy is being designed at the Lawrence Berkeley Laboratory. Performance requirements have been established. Ions from helium to argon can be accelerated to a maximum energy of 800 MeV/nucleon with intensities in the range 10/sup 8/ to 10/sup 9/ particles per second. The accelerator subsystems consist of a linac injector, a synchrotron, and a beam-delivery system. Specifications have been developed for many of the technical components, and some details of the technical design are presented.

Gough, R.; Alonso, J.; Elioff, T.

1983-03-01

368

High transformer ratio drive beams for wakefield accelerator studies  

SciTech Connect

For wakefield based acceleration schemes, use of an asymmetric (or linearly ramped) drive bunch current profile has been predicted to enhance the transformer ratio and generate large accelerating wakes. We discuss plans and initial results for producing such bunches using the 20 to 23 GeV electron beam at the FACET facility at SLAC National Accelerator Laboratory and sending them through plasmas and dielectric tubes to generate transformer ratios greater than 2 (the limit for symmetric bunches). The scheme proposed utilizes the final FACET chicane compressor and transverse collimation to shape the longitudinal phase space of the beam.

England, R. J.; Ng, C.-K.; Frederico, J.; Hogan, M. J.; Litos, M.; Muggli, P.; Joshi, C.; An, W.; Andonian, G.; Mori, W.; Lu, W. [SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States); Max Planck Institute for Physics, 80805 Munich (Germany); University of California Los Angeles, Los Angeles, CA 90095 (United States); Tsinghua University, Beijing (China)

2012-12-21

369

Timescale Correlation between Marine Atmospheric Exposure and Accelerated Corrosion Testing  

NASA Technical Reports Server (NTRS)

Evaluation of metal-based structures has long relied on atmospheric exposure test sites to determine corrosion resistance in marine environments. Traditional accelerated corrosion testing relies on mimicking the exposure conditions, often incorporating salt spray and ultraviolet (UV) radiation, and exposing the metal to continuous or cyclic conditions of the corrosive environment. Their success for correlation to atmospheric exposure is often a concern when determining the timescale to which the accelerated tests can be related. Accelerated laboratory testing, which often focuses on the electrochemical reactions that occur during corrosion conditions, has yet to be universally accepted as a useful tool in predicting the long term service life of a metal despite its ability to rapidly induce corrosion. Although visual and mass loss methods of evaluating corrosion are the standard and their use is imperative, a method that correlates timescales from atmospheric exposure to accelerated testing would be very valuable. This work uses surface chemistry to interpret the chemical changes occurring on low carbon steel during atmospheric and accelerated corrosion conditions with the objective of finding a correlation between its accelerated and long-term corrosion performance. The current results of correlating data from marine atmospheric exposure conditions at the Kennedy Space Center beachside corrosion test site, alternating seawater spray, and immersion in typical electrochemical laboratory conditions, will be presented. Key words: atmospheric exposure, accelerated corrosion testing, alternating seawater spray, marine, correlation, seawater, carbon steel, long-term corrosion performance prediction, X-ray photoelectron spectroscopy.

Montgomery, Eliza L.; Calle, Luz Marina; Curran, Jerone C.; Kolody, Mark R.

2011-01-01

370

An accelerator technology legacy  

SciTech Connect

Accelerator technology has been a major beneficiary of the investment made over the last decade. It is the intention of this paper to provide the reader with a glimpse of the broad nature of those advances. Development has been on a broad front and this paper can highlight only a few of those. Two spin-off applications will be outlined -- a concept for a compact, active, beam probe for solar body exploration and the concept for an accelerator-driven transmutation system for energy production.

Heighway, E.A.

1994-11-01

371

Electrostatics of pyroelectric accelerators  

NASA Astrophysics Data System (ADS)

Derivations for equations for calculating the potential and field strength in both single-crystal and two-crystal pyroelectric accelerators are presented. Such expressions for the single-crystal system are well established in the literature, but with cursory derivations. We provide a rigorous derivation of the single-crystal system and expand upon this physical understanding to derive expressions for the potential and field in a two-crystal system. The expressions are verified with finite element modeling and compared with experimental results. This allows for better understanding of pyroelectric accelerators.

Fullem, T. Z.; Danon, Y.

2009-10-01

372

A Smoother Acceleration  

NSDL National Science Digital Library

Some may argue that gifted children have many education options, but these options do not always help gifted students learn science. Unfortunately, gifted students often do not reach their full academic potential--they are frequently less motivated to succeed because they are not being academically challenged in regular classrooms (McCoach and Siegle 2003). To counter these problems, a strong option for educating gifted students is acceleration. This article describes the challenges that more and more gifted students face when accelerating, particularly when skipping an entire academic year. Strategies to lessen their intensity and duration and, ultimately, help gifted students to succeed are also included.

Chapman, Christine

2009-03-01

373

Accelerated molecular dynamics methods  

SciTech Connect

The molecular dynamics method, although extremely powerful for materials simulations, is limited to times scales of roughly one microsecond or less. On longer time scales, dynamical evolution typically consists of infrequent events, which are usually activated processes. This course is focused on understanding infrequent-event dynamics, on methods for characterizing infrequent-event mechanisms and rate constants, and on methods for simulating long time scales in infrequent-event systems, emphasizing the recently developed accelerated molecular dynamics methods (hyperdynamics, parallel replica dynamics, and temperature accelerated dynamics). Some familiarity with basic statistical mechanics and molecular dynamics methods will be assumed.

Perez, Danny [Los Alamos National Laboratory

2011-01-04

374

Linear accelerator for production of tritium: Physics design challenges  

SciTech Connect

In the summer of 1989, a collaboration between Los Alamos National Laboratory and Brookhaven National Laboratory conducted a study to establish a reference design of a facility for accelerator production of tritium (APT). The APT concept is that of a neutron-spallation source, which is based on the use of high-energy protons to bombard lead nuclei, resulting in the production of large quantities of neutrons. Neutrons from the lead are captured by lithium to produce tritium. This paper describes the design of a 1.6-GeV, 250-mA proton cw linear accelerator for APT.

Wangler, T.P.; Lawrence, G.P.; Bhatia, T.S.; Billen, J.H.; Chan, K.C.D.; Garnett, R.W.; Guy, F.W.; Liska, D.; Nath, S.; Neuschaefer, G.; Shubaly, M.

1990-01-01

375

Stirling laboratory research engine survey report  

NASA Technical Reports Server (NTRS)

As one step in expanding the knowledge relative to and accelerating the development of Stirling engines, NASA, through the Jet Propulsion Laboratory (JPL), is sponsoring a program which will lead to a versatile Stirling Laboratory Research Engine (SLRE). An objective of this program is to lay the groundwork for a commercial version of this engine. It is important to consider, at an early stage in the engine's development, the needs of the potential users so that the SLRE can support the requirements of educators and researchers in academic, industrial, and government laboratories. For this reason, a survey was performed, the results of which are described.

Anderson, J. W.; Hoehn, F. W.

1979-01-01

376

High current electron linacs (advanced test accelerator/experimental test accelerator)  

SciTech Connect

The high current induction accelerator development at the Lawrence Livermore National Laboratory is described. The ATA facility is designed for 10 kA peak currents, 50 nsec pulse lengths and 50 MeV energies. At this time, half of the design current has been accelerated through the entire machine to particle energies of about 45 MeV. Current problem areas and operational experience to date will be discussed. Several key technical areas required development for the ATA machine; this report will survey these developments. The control of transverse beam instabilities required an accelerating cavity design with very low Q. Electron sources capable of 10 kA operation at high rep rates were developed using a plasma sparkboard approach. The pulse power systems on ATA, using the same type of spark gap switches as ETA, have exhibited excellent operational reliability.

Briggs, R.J.

1984-04-30

377

Laser Wakefield Accelerators towards table-top accelerators and bright synchrotron sources  

NASA Astrophysics Data System (ADS)

Laser wakefield accelerators (LWFA) have the potential to lead a new generation of compact table top accelerators. In particular, they could be an attractive driver for a whole range of light source applications. Recently it has been demonstrated that LWFAs can be a source of very bright x-rays. These x-rays are generated due to the transverse (betatron) oscillations of the electron beam as it is being accelerated. Experiments with 100 TW class lasers have shown the peak brightness of this betatron source to be comparable to 3rd generation light sources (S. Kneip et al, Nature Physics 6, 980-983 (2010)). I will present results from recent experiments on x-ray production using the 250 TW Astra Gemini Laser located at the Rutherford Appleton Laboratory.

Bloom, M.; Streeter, M. J.; Kneip, S.; Bendoyro, R.; Döpp, A.; Holloway, J.; Jiang, J.; Lopes, N.; Najmudin, Z.; Nakamura, H.; Symes, D.; Mangles, S. P. D.

2011-11-01

378

Testbeam and laboratory test results of irradiated 3D CMS pixel detectors  

NASA Astrophysics Data System (ADS)

The CMS silicon pixel detector is the tracking device closest to the LHC p-p collisions, which precisely reconstructs the charged particle trajectories. The planar technology used in the current innermost layer of the pixel detector will reach the design limit for radiation hardness at the end of Phase I upgrade and will need to be replaced before the Phase II upgrade in 2020. Due to its unprecedented performance in harsh radiation environments, 3D silicon technology is under consideration as a possible replacement of planar technology for the High Luminosity-LHC or HL-LHC. 3D silicon detectors are fabricated by the Deep Reactive-Ion-Etching (DRIE) technique which allows p- and n-type electrodes to be processed through the silicon substrate as opposed to being implanted through the silicon surface. The 3D CMS pixel devices presented in this paper were processed at FBK. They were bump bonded to the current CMS pixel readout chip, tested in the laboratory, and testbeams carried out at FNAL with the proton beam of 120 GeV/c. In this paper we present the laboratory and beam test results for the irradiated 3D CMS pixel devices.

Bubna, Mayur; Alagoz, Enver; Cervantes, Mayra; Krzywda, Alex; Arndt, Kirk; Obertino, Margherita; Solano, Ada; Dalla Betta, Gian-Franco; Menace, Dario; Moroni, Luigi; Uplegger, Lorenzo; Rivera, Ryan; Osipenkov, Ilya; Andresen, Jeff; Bolla, Gino; Bortoletto, Daniela; Boscardin, Maurizio; Marie Brom, Jean; Brosius, Richard; Chramowicz, John; Cumalat, John; Dinardo, Mauro; Dini, Paolo; Jensen, Frank; Kumar, Ashish; Kwan, Simon; Lei, C. M.; Povoli, Marco; Prosser, Alan; Ngadiuba, Jennifer; Perera, Lalith; Shipsey, Ian; Tan, Ping; Tentindo, Silvia; Terzo, Stefano; Tran, Nhan; Wagner, Stephen R.

2013-12-01

379

Negative hydrogen ion sources for accelerators  

SciTech Connect

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

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

2005-08-01

380

Theme: Laboratory Facilities Improvement.  

ERIC Educational Resources Information Center

Includes "Laboratory Facilities Improvement" (Miller); "Remodeling Laboratories for Agriscience Instruction" (Newman, Johnson); "Planning for Change" (Mulcahy); "Laboratory Facilities Improvement for Technology Transfer" (Harper); "Facilities for Agriscience Instruction" (Agnew et al.); "Laboratory Facility Improvement" (Boren, Dwyer); and…

Miller, Glen M.; And Others

1993-01-01

381

Accelerated Learning Takes Off.  

ERIC Educational Resources Information Center

Trainers at Bell Atlantic converted two courses to an accelerated learning format. As a result, the costs of one course were reduced by 42 percent and the other by 57 percent. The satisfaction of students and trainers greatly improved, as did their job performance. (JOW)

Gill, Mary Jane; Meier, David

1989-01-01

382

Acceleration and Mass  

NSDL National Science Digital Library

Although this lab is not an inquiry activity, it is very important in learning about acceleration and mass. It is a deeply held misconception among students that objects of different masses fall at different rates. Simply explaining that this is not true

Horton, Michael

2009-05-30

383

Pulsed electromagnetic gas acceleration  

NASA Technical Reports Server (NTRS)

Detailed measurements of the axial velocity profile and electromagnetic structure of a high power, quasi-steady MPD discharge are used to formulate a gasdynamic model of the acceleration process. Conceptually dividing the accelerated plasma into an inner flow and an outer flow, it is found that more than two-thirds of the total power in the plasma is deposited in the inner flow, accelerating it to an exhaust velocity of 12.5 km/sec. The outer flow, which is accelerated to a velocity of only 6.2 km/sec, appears to provide a current conduction path between the inner flow and the anode. Related cathode studies have shown that the critical current for the onset of terminal voltage fluctuations, which was recently shown to be a function of the cathode area, appears to reach an asymptote for cathodes of very large surface area. Detailed floating potential measurements show that the fluctuations are confined to the vicinity of the cathode and hence reflect a cathode emission process rather than a fundamental limit on MPD performance.

Jahn, R. G.; Vonjaskowsky, W. F.; Clark, K. E.

1974-01-01

384

High intensity hadron accelerators  

SciTech Connect

Accelerators needed to examine the intersections between nuclear and particle physics will require GeV energies with high beam intensities. Concerns about such high intensity machines are beam focusing, intensity limitations, power economics, and heavy ion applicability. These topics are the basis for this discussion. (AIP)

Teng, L.C.

1984-11-15

385

Plasma based accelerators  

SciTech Connect

A plasma medium can support a variety of wave motions which may be useful for accelerating charged particles. For highly relativistic beams the longitudinal electrostatic wave is most suitable and may be driven by laser or by particle beams. The basic principles, limitations and prospects for these devices are discussed.

Evans, R.G.

1987-05-05

386

Radioisotope Dating with Accelerators.  

ERIC Educational Resources Information Center

Explains a new method of detecting radioactive isotopes by counting their accelerated ions rather than the atoms that decay during the counting period. This method increases the sensitivity by several orders of magnitude, and allows one to find the ages of much older and smaller samples. (GA)

Muller, Richard A.

1979-01-01

387

''Angara-5'' Accelerator System.  

National Technical Information Service (NTIS)

Some considerations are given with respect to the accelerating system ''Angara-5,'' which has a beam power of 10 exp 14 W. The system is intended for the experiments of pulse initiation of the controlled fusion reaction by the high-current electron beams ...

E. P. Velikhov V. A. Glukhikh O. A. Gusev

1978-01-01

388

Math Acceleration for All  

ERIC Educational Resources Information Center

In 1995, South Side Middle School in New York implemented an organizational change and provided accelerated math instruction for all students. It is proposed that taking advance math in high school was strongly associated with successful completion of college, which inturn, correlates with subsequent educational and employment opportunities.

Burris, Carol Corbett; Heubert, Jay P.; Levin, Henry M.

2004-01-01

389

G Accelerator Applications  

NASA Astrophysics Data System (ADS)

This paper will review GEANT4 applications and extensions for accelerator studies, both as a general framework and for the simulation of specific accelerators. G4Beamline is a Geant4-based program intended to easily simulate many different aspects of beam-line design. G4Beamline implements accelerator components via an object-oriented ASCII input format. For instance, it allows the definition of a quadrupole magnet by its physical geometry, materials, and also magnetic field (including several models for fringe fields). The Muon Ionization Cooling Experiment (MICE) poses some challenges for simulation not normally found in a particle physics experiment. The G4MICE package is under development to allow a complete simulation of the MICE cooling channel (including the simulation of magnetic and RF fields) and instrumentation. BDSIM is a Geant4 based code that implements fast accelerator-style tracking for particles within the beam-pipe together with the full set of Geant4 physics processes for particles that leave the beam-pipe. The program has been used to simulate and optimize the design of proposed electron positron linear colliders (ILC and CLIC). The input to the code is based on the MAD format and allows definition of geometries, fields and materials. Geometry descriptions common to those used by the ILC detector groups have enabled common studies of the interaction region, specification of the required collimation depths and optimization of the extraction lines.

Ellis, Malcolm; Blair, Grahame; Torun, Yagmur; Roberts, Tom

2006-04-01

390

Accelerating business analytics applications  

Microsoft Academic Search

Business text analytics applications have seen rapid growth, driven by the mining of data for various decision making processes. Regular expression processing is an important component of these applications, consuming as much as 50% of their total execution time. While prior work on accelerating regular expression processing has focused on Network Intrusion Detection Systems, business analytics applications impose different requirements

Valentina Salapura; Tejas Karkhanis; Priya Nagpurkar; Jose Moreira

2012-01-01

391

Future accelerator magnet needs  

Microsoft Academic Search

Superconducting magnet technology is continually evolving in order to meet the demanding needs of new accelerators and to provide necessary upgrades for existing machines. A variety of designs are now under development, including high fields and gradients, rapid cycling and novel coil configurations. This paper presents a summary of R&D programs in the EU, Japan and the USA. A performance

Arnaud Devred; Stephen A. Gourlay; Akira Yamamoto

2005-01-01

392

Test Stand for Linear Induction Accelerator Optimization  

SciTech Connect

Lawrence Livermore National Laboratory has designed and constructed a test stand to improve the voltage regulation in our Flash X-Ray (FXR) accelerator cell. The goal is to create a more mono-energetic electron beam that will create an x-ray source with a smaller spot size. Studying the interaction of the beam and pulse-power system with the accelerator cell will improve the design of high-current accelerators at Livermore and elsewhere. On the test stand, a standard FXR cell is driven by a flexible pulse-power system and the beam current is simulated with a switched center conductor. The test stand is fully instrumented with high-speed digitizers to document the effect of impedance mismatches when the cell is operated under various full-voltage conditions. A time-domain reflectometry technique was also developed to characterize the beam and cell interactions by measuring the impedance of the accelerator and pulse-power component. Computer models are being developed in parallel with the testing program to validate the measurements and evaluate different design changes. Both 3D transient electromagnetic and circuit models are being used.

Ong, M; DeHope, B; Griffin, K; Goerz, D; Kihara, R; Vogtlin, G; Zentler, J M; Scarpetti, R

2003-06-03

393

X-Rays from Accelerated Ion Interactions  

NASA Astrophysics Data System (ADS)

We have developed in detail the theory of X-ray line and continuum production due to atomic interactions of accelerated ions, incorporating in our calculations information from a broad range of laboratory measurements. We applied our calculations to the Orion region from which nuclear gamma-ray line observations with the COMPTEL instrument on the Compton Gamma Ray Observatory (CGRO) were reported. The accelerated particles which produce this gamma-ray emission via nuclear reactions also produce X-ray lines via atomic interactions. We predict strong, relatively broad line emission in the range from 0.5 to 1 keV, mainly due to de-excitations in fast O ions. Current ROSAT observations of Orion do not provide unambiguous signatures for X-ray production by accelerated ions. However, if future X-ray observations with high spectral resolution would confirm the predicted X-rays, the combined analysis of the X-ray and gamma-ray data will set important constraints on the origin of the accelerated particles and their interaction model.

Tatischeff, Vincent; Ramaty, Reuven; Kozlovsky, Benzion

1998-09-01

394

Acceleration of polarized proton beams  

SciTech Connect

The acceleration of polarized beams in circular accelerators is complicated by the numerous depolarizing spin resonances. Using a partial Siberian snake and a rf dipole that ensure stable adiabatic spin motion during acceleration has made it possible to accelerate polarized protons to 25 GeV at the Brookhaven AGS. Full Siberian snakes are being developed for RHIC to make the acceleration of polarized protons to 250 GeV possible. A similar scheme is being studied for the 800 GeV HERA proton accelerator.

Roser, T.

1998-12-31

395

Stacked insulator induction accelerator gaps  

SciTech Connect

Stacked insulators, with alternating layers of insulating material and conducting film, have been shown to support high surface electrical field stresses. We have investigated the application of the stacked insulator technology to the design of induction accelerator modules for the Relativistic-Klystron Two-Beam Accelerator program. The rf properties of the accelerating gaps using stacked insulators, particularly the impedance at frequencies above the beam pipe cutoff frequency, are investigated. Low impedance is critical for Relativistic-Klystron Two-Beam Accelerator applications where a high current, bunched beam is trsnsported through many accelerating gaps. An induction accelerator module designs using a stacked insulator is presented.

Houck, T.I.; Westenskow, G.A.; Kim, J.S.; Eylon, S.; Henestroza, E.; Yu, S.S.; Vanecek, D.

1997-05-01

396

Accelerating in the Future: Lasers Start to Produce Quality High Energy Electron Beams  

ScienceCinema

Twenty-five years ago, a new method was proposed for the acceleration of electrons to high energies using lasers. The simplest implementation of a so-called laser wakefield accelerator involves sending an intense laser pulse through a gas to ionize it and form a plasma of dissociated electrons and ions. The radiation pressure of the laser pushes the plasma electrons aside, creating a density modulation, or 'wake'. This changing electron density can result in fields that accelerate particles thousands of times more strongly than in conventional machines, accelerating electrons to high energies in short distances. The compactness of these accelerators would allow higher energies for the frontiers of fundamental physics and make clinical and laboratory applications of accelerators practical. In work that brings the promise of laser-driven particle accelerators dramatically closer to reality, we have produced high-quality electron beams in a plasma channel based accelerating structure akin to an optical fiber of only a few millimeters long.

397

The Tandem-ALPI-PIAVE accelerator complex of LNL  

SciTech Connect

Heavy ion beams are delivered at the Laboratori Nazionali di Legnaro by the accelerator complex Tandem-ALPI-PIAVE. The Tandem XTU is a Van de Graaff accelerator normally operated at terminal voltages of up to about 15 MV. The Tandem accelerator can be operated in stand-alone mode or as an injector for the linac booster ALPI. The linear accelerator ALPI is built of superconducting resonant cavities and consists of a low-beta branch, particularly important for the acceleration of the heavier mass ions, a medium-beta branch, and a high-beta branch. ALPI can be operated also with the PIAVE injector that consists of a superconducting linac and an ECR source. The PIAVE source was mainly used for the acceleration of intense noble gas beams but most recently also a first metallic beam was delivered to the users. The accelerator complex delivers beams of ions from protons to gold in three experimental areas on 11 different beam lines. A rich scientific activity is ongoing at the Tandem-ALPI-PIAVE accelerator complex, beam time being shared between nuclear physics research and applied and interdisciplinary physics research. An overview of the present status and perspectives of the Tandem-ALPI-PIAVE complex and its physics program is given in the present paper.

Ur, C. A. [INFN Sezione di Padova, 35131 Padova (Italy)

2013-07-18

398

Charge Diagnostics for Laser Plasma Accelerators  

SciTech Connect

The electron energy dependence of a scintillating screen (Lanex Fast) was studied with sub-nanosecond electron beams ranging from 106 MeV to 1522 MeV at the Lawrence Berkeley National Laboratory Advanced Light Source (ALS) synchrotron booster accelerator. The sensitivity of the Lanex Fast decreased by 1% per 100 MeV increase of the energy. The linear response of the screen against the charge was verified with charge density and intensity up to 160 pC/mm{sup 2} and 0.4 pC/ps/mm{sup 2}, respectively. For electron beams from the laser plasma accelerator, a comprehensive study of charge diagnostics has been performed using a Lanex screen, an integrating current transformer, and an activation based measurement. The charge measured by each diagnostic was found to be within {+-}10%.

Nakamura, K.; Gonsalves, A. J.; Lin, C.; Sokollik, T.; Smith, A.; Rodgers, D.; Donahue, R.; Bryne, W.; Leemans, W. P. [Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States)

2010-11-04

399

Space Experiments with Particle Accelerators (SEPAC)  

NASA Technical Reports Server (NTRS)

The purpose of Space Experiments with Particle Accelerators (SEPAC) on the Atmospheric Laboratory for Applications and Science (ATLAS 1) mission, is to carry out active and interactive experiments on and in the earth's ionosphere, atmosphere, and magnetosphere. The instruments to be used are an electron beam accelerator (EBA), plasma contactor, and associated instruments the purpose of which is to perform diagnostic, monitoring, and general data taking functions. Four major classes of investigations are to be performed by SEPAC. They are: beam plasma physics, beam-atmosphere interactions, the use of modulated electron beams as transmitting antennas, and the use of electron beams for remote sensing of electric and magnetic fields. The first class consists mainly of onboard plasma physics experiments to measure the effects of phenomena in the vicinity of the shuttle. The last three are concerned with remote effects and are supported by other ATLAS 1 investigations as well as by ground-based observations.

Obayashi, Tatsuzo

1988-01-01

400

BNL Sources Development Laboratory  

SciTech Connect

The NSLS has a long-standing interest in providing the best possible synchrotron radiation sources for its user community, and hence, has recently established the Source Development Laboratory (SDL) to pursue research into fourth generation synchrotron radiation sources. A major element of the program includes development of a high peak power FEL meant to operate in the vacuum ultraviolet. The objective of the program is to develop the source, and experimental technology together to provide the greatest impact on UV science. The accelerator under construction for the SDL consists of a high brightness RF photocathode electron gun followed by a 230 MeV short pulse linac incorporating a magnetic chicane for pulse compression. The gun drive laser is a wide bandwidth Ti: Sapphire regenerative amplifier capable of pulse shaping which will be used to study non- linear emittance compensation. Using the compressor, 1 nC bunches with a length as small as 50 {mu}m sigma (2 kA peak current) are available for experiments. In this paper we briefly describe the facility and detail our plans for utilizing the 10 m long NISUS wiggler to carry out single pass FEL experiments. These include a 1 {mu}m SASE demonstration, a seeded beam demonstration at 300 nm, and a High Gain Harmonic Generation experiment at 200 mn. The application of chirped pulse amplification to this type of FEL will also be discussed.

Ben-Zvi, I.; Graves, W.; Heese, R.; Johnson, E.D.; Krinsky, S.; Yu, L.H.

1997-01-01

401

Accelerated Weathering of Rocks.  

National Technical Information Service (NTIS)

The project concerns correlation between weathering indices obtained from samples of one type of sedimentary rock (graywacke) and those obtained after laboratory agency tests of the same rocks. Study is made of the process of natural alteration in three s...

L. Aires-Barros

1977-01-01

402

Laser-driven electron accelerators  

SciTech Connect

The following possibilities are discussed: inverse free electron laser (wiggler accelerator); inverse Cerenkov effect; plasma accelerator; dielectric tube; and grating linac. Of these, the grating acceleraton is considered the most attractive alternative. (GHT)

Palmer, R.B.

1981-01-01

403

Particle Acceleration in Hypernova Explosion  

NASA Astrophysics Data System (ADS)

The relativistic shock break out at the surface of Hypernova star is considered. The hydrodynamical acceleration of outer layers of Hypernova envelope is investigated. The characteristics of accelerated particles are estimated.

Marchenko, V. V.; Hnatyk, B. I.; Pekur, D. V.

2009-12-01

404

Particle Acceleration in Hypernova Explosion  

Microsoft Academic Search

The relativistic shock break out at the surface of Hypernova star is considered. The hydrodynamical acceleration of outer layers of Hypernova envelope is investigated. The characteristics of accelerated particles are estimated.

V. V. Marchenko; B. I. Hnatyk; D. V. Pekur

2009-01-01

405

Review of ion accelerators  

SciTech Connect

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.

1990-06-01

406

Hypervelocity plate acceleration  

SciTech Connect

Shock tubes have been used to accelerate 1.5-mm-thick stainless steel plates to high velocity while retaining their integrity. The fast shock tubes are 5.1-cm-diameter, 15.2-cm-long cylinders of PBX-9501 explosive containing a 1.1-cm-diameter cylindrical core of low-density polystyrene foam. The plates have been placed directly in contact with one face of the explosive system. Plane-wave detonation was initiated on the opposite face. A Mach disk was formed in the imploding styrofoam core, which provided the impulse required to accelerate the metal plate to high velocity. Parametric studies were made on this system to find the effect of varying plate metal, plate thickness, foam properties, and addition of a barrel. A maximum plate velocity of 9.0 km/s has been observed. 6 refs., 17 figs.

Marsh, S.P.; Tan, T.H.

1991-01-01

407

Hardware Accelerated Simulated Radiography  

SciTech Connect

We present the application of hardware accelerated volume rendering algorithms to the simulation of radiographs as an aid to scientists designing experiments, validating simulation codes, and understanding experimental data. The techniques presented take advantage of 32 bit floating point texture capabilities to obtain validated solutions to the radiative transport equation for X-rays. An unsorted hexahedron projection algorithm is presented for curvilinear hexahedra that produces simulated radiographs in the absorption-only regime. A sorted tetrahedral projection algorithm is presented that simulates radiographs of emissive materials. We apply the tetrahedral projection algorithm to the simulation of experimental diagnostics for inertial confinement fusion experiments on a laser at the University of Rochester. We show that the hardware accelerated solution is faster than the current technique used by scientists.

Laney, D; Callahan, S; Max, N; Silva, C; Langer, S; Frank, R

2005-04-12

408

Pulsed Drift Tube Accelerator  

SciTech Connect

The pulsed drift-tube accelerator (DTA) concept was revived by Joe Kwan and John Staples and is being considered for the HEDP/WDM application. It could be used to reach the full energy or as an intermediate accelerator between the diode and a high gradient accelerator such as multi-beam r.f. In the earliest LBNL HIF proposals and conceptual drivers it was used as an extended injector to reach energies where an induction linac with magnetic quadrupoles is the best choice. For HEDP, because of the very short pulse duration, the DTA could provide an acceleration rate of about 1MV/m. This note is divided into two parts: the first, a design based on existing experience; the second, an optimistic extrapolation. The first accelerates 16 parallel K{sup +} beams at a constant line charge density of 0.25{micro} C/m per beam to 10 MeV; the second uses a stripper and charge selector at around 4MeV followed by further acceleration to reach 40 MeV. Both benefit from more compact sources than the present 2MV injector source, although that beam is the basis of the first design and is a viable option. A pulsed drift-tube accelerator was the first major HIF experiment at LBNL. It was designed to produce a 2{micro}s rectangular 1 Ampere C{sub s}{sup +} beam at 2MeV. It ran comfortably at 1.6MeV for several years, then at lower voltages and currents for other experiments, and remnants of that experiment are in use in present experiments, still running 25 years later. The 1A current, completely equivalent to 1.8A K{sup +}, was chosen to be intermediate between the beamlets appropriate for a multi-beam accelerator, and a single beam of, say, 10A, at injection energies. The original driver scenarios using one large beam on each side of the reactor rapidly fell out of favor because of the very high transverse and longitudinal fields from the beam space charge, circa 1MV/cm and 250 kV/cm respectively, near the chamber and because of aberrations in focusing a large diameter beam down to a 1mm radius spot at a distance of 10m. Almost all subsequent work and the present concept have invoked multiple beams. For HEDP the major differences are that the focal distance can be centimeters instead of meters, provided strong-enough lenses exist and they do, thereby allowing much higher transverse and longitudinal emittances than driver concepts, and focusing parallel small beams is easier than one big beam.

Faltens, A.

2004-10-25

409

Accelerator research studies  

SciTech Connect

The Accelerator Research Studies program at the University of Maryland, sponsored by the Department of Energy under grant number DE-FG05-91ER40642, is currently in the first year of a three-year funding cycle. The program consists of the following three tasks: TASK A, Study of Transport and Longitudinal Compression of Intense, High-Brightness Beams, TASK B, Study of Collective Ion Acceleration by Intense Electron Beams and Pseudospark Produced High Brightness Electron Beams; TASK C, Study of a Gyroklystron High-power Microwave Source for Linear Colliders. In this report we document the progress that has been made during the past year for each of the three tasks.

Not Available

1992-01-01

410

Adaptive control for accelerators  

DOEpatents

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

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

1991-01-01

411

NEW ACCELERATION METHODS  

SciTech Connect

But a glance at the Livingston chart, Fig. 1, of accelerator particle energy as a function of time shows that the energy has steadily, exponentially, increased. Equally significant is the fact that this increase is the envelope of diverse technologies. If one is to stay on, or even near, the Livingston curve in future years then new acceleration techniques need to be developed. What are the new acceleration methods? In these two lectures I would like to sketch some of these new ideas. I am well aware that they will probably not result in high energy accelerators within this or the next decade, but conversely, it is likely that these ideas will form the basis for the accelerators of the next century. Anyway, the ideas are stimulating and suffice to show that accelerator physicists are not just 'engineers', but genuine scientists deserving to be welcomed into the company of high energy physicists. I believe that outsiders will find this field surprisingly fertile and, certainly fun. To put it more personally, I very much enjoy working in this field and lecturing on it. There are a number of review articles which should be consulted for references to the original literature. In addition there are three books on the subject. Given this material, I feel free to not completely reference the material in the remainder of this article; consultation of the review articles and books will be adequate as an introduction to the literature for references abound (hundreds are given). At last, by way of introduction, I should like to quote from the end of Ref. 2 for I think the remarks made there are most germane. Remember that the talk was addressed to accelerator physicists: 'Finally, it is often said, I think by physicists who are not well-informed, that accelerator builders have used up their capital and now are bereft of ideas, and as a result, high energy physics will eventually--rather soon, in fact--come to a halt. After all, one can't build too many machines greater than 27 km, and soon one will run out of space or money (almost surely money before space). This argument seems terribly wrong to me, and worse than that possibly destructive, for it will have a serious effect if it causes, as it well might, young people to elect to go into fields other than high energy physics. The proper response, I believe, is to point--in considerable detail--to some of the new concepts which show by example that we are far from being out of new ideas. Some of these concepts shall, in my view, be, or lead to, the 'stocks in trade' of the next century, and thus they will allow high energy physics to be as exciting then as it is now. It is our job to make it all happen.

Sessler, A.M.

1984-07-01

412

Commissioning the GTA accelerator  

SciTech Connect

The Ground Test Accelerator (GTA) is supported by the Strategic Defense command as part of their Neutral Particle Beam (NPB) program. Neutral particles have the advantage that in space they are unaffected by the earth's magnetic field and travel in straight lines unless they enter the earth's atmosphere and become charged by stripping. Heavy particles are difficult to stop and can probe the interior of space vehicles; hence, NPB can function as a discriminator between warheads and decoys. We are using GTA to resolve the physics and engineering issues related to accelerating, focusing, and steering a high-brightness, high-current H{sup -} beam and then neutralizing it. Our immediate goal is to produce a 24-MeV, 50mA device with a 2% duty factor.

Sander, O.R.; Atkins, W.H.; Bolme, G.O.; Bowling, S.; Brown, S.; Cole, R.; Gilpatrick, J.D.; Garnett, R.; Guy, F.W.; Ingalls, W.B.; Johnson, K.F.; Kerstiens, D.; Little, C.; Lohsen, R.A.; Lloyd, S.; Lysenko, W.P.; Mottershead, C.T.; Neuschaefer, G.; Power, J.; Rusthoi, D.P.; Sandoval, D.P. Stevens, R.R. Jr.; Vaughn, G.; Wadlinger, E.A.; Yuan, V. (Los Alamos National Lab., NM (United States)); Connolly, R.; Weiss, R. (Gr

1992-01-01

413

Commissioning the GTA accelerator  

SciTech Connect

The Ground Test Accelerator (GTA) is supported by the Strategic Defense command as part of their Neutral Particle Beam (NPB) program. Neutral particles have the advantage that in space they are unaffected by the earth`s magnetic field and travel in straight lines unless they enter the earth`s atmosphere and become charged by stripping. Heavy particles are difficult to stop and can probe the interior of space vehicles; hence, NPB can function as a discriminator between warheads and decoys. We are using GTA to resolve the physics and engineering issues related to accelerating, focusing, and steering a high-brightness, high-current H{sup -} beam and then neutralizing it. Our immediate goal is to produce a 24-MeV, 50mA device with a 2% duty factor.

Sander, O.R.; Atkins, W.H.; Bolme, G.O.; Bowling, S.; Brown, S.; Cole, R.; Gilpatrick, J.D.; Garnett, R.; Guy, F.W.; Ingalls, W.B.; Johnson, K.F.; Kerstiens, D.; Little, C.; Lohsen, R.A.; Lloyd, S.; Lysenko, W.P.; Mottershead, C.T.; Neuschaefer, G.; Power, J.; Rusthoi, D.P.; Sandoval, D.P. Stevens, R.R. Jr.; Vaughn, G.; Wadlinger, E.A.; Yuan, V. [Los Alamos National Lab., NM (United States); Connolly, R.; Weiss, R. [Grumman Space and Electronics Corp., Princeton, NJ (United States); Saadatmand, K. [Grumman Corp., Bethpage, NY (United States). Corporate Research Center

1992-09-01

414

Plasma wave accelerator. II  

SciTech Connect

It was shown that the insertion of a cross magnetic field prevents the particles from getting out of phase with the electric field of the plasma wave in the beat wave accelerator scheme. Thus, using a CO/sub 2/ laser, n/sub c//n/sub e/ = (..omega../sub 0//..omega../sub p/)/sup 2/ approx. 35, and a 300 kG magnetic field, electrons can be (in principle) accelerated to 100 GeV in 2 meters. For comparison without the magnetic field, the same energies may be obtained in a n/sub c//n/sub e/ approx. 10/sup 5/ plasma over a distance of 100 meters.

Mori, W.; Joshi, C.; Dawson, J.M.

1982-01-01

415

Accelerometer: Centripetal Acceleration  

NSDL National Science Digital Library

Students work as physicists to understand centripetal acceleration concepts. They also learn about a good robot design and the accelerometer sensor. They also learn about the relationship between centripetal acceleration and centripetal forceâgoverned by the radius between the motor and accelerometer and the amount of mass at the end of the robot's arm. Students graph and analyze data collected from an accelerometer, and learn to design robots with proper weight distribution across the robot for their robotic arms. Upon using a data logging program, they view their own data collected during the activity. By activity end , students understand how a change in radius or mass can affect the data obtained from the accelerometer through the plots generated from the data logging program. More specifically, students learn about the accuracy and precision of the accelerometer measurements from numerous trials.

Applying Mechatronics to Promote Science (AMPS) GK-12 Program,

416

Principles of Charged Particle Acceleration  

NSDL National Science Digital Library

This learning resources comprise a healthy introduction to charged particle acceleration. The site, by Stanley Humphries, a professor of electrical and computer engineering at University of New Mexico, amounts to an online textbook (.pdf) introducing the theory of charged particle acceleration. The book's fifteen chapters (with bibliography) summarize "the principles underlying all particle accelerators" and provide "a reference collection of equations and material essential to accelerator development and beam applications."

417

Phase stability in surfatron acceleration  

SciTech Connect

Particle motion in a laser beat-wave plasma field with a transverse magnetic field is explored. It is determined that stable, phase-space buckets for acceleration are established by these fields and that particles injected near the beat-wave phase velocity can be trapped in these buckets and accelerated indefinitely, with stable phase-energy oscillations about the accelerating phase. Parameters for high-energy accelerators and lower energy demonstration experiments are presented.

Neuffer, D.

1983-01-01

418

Progress on laser plasma accelerators  

SciTech Connect

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

Chen, P.

1986-04-01

419

Microwave techniques for diagnostic laboratories.  

PubMed

Microwaves (MWs) were first introduced as a method of fixation just over 20 years ago. In recent years their use has extended far beyond that of a safe, clean and rapid method of fixation of tissue blocks and large specimens, including brains. MWs accelerate the action of cross-linking fixatives and can greatly accelerate the various stages of tissue processing to produce a paraffin block in 30 min. An extensive range of ultrafast MW-stimulated special stains has been developed, and immunohistochemical procedures can be completed in 20 min by employing MWs. Cellular antigens are distinctly better preserved in tissues fixed by MWs than by conventional cross-linking fixatives. Also, the cytomorphology of cryostat sections irradiated in Wolman's solution is clearly improved. MWs can similarly be applied for fixation and staining of preparations for transmission and scanning electron microscopy, and they also greatly accelerate polymerisation of resins. In the current climate of cost containment, this wide range of applications makes the MW oven an invaluable addition to the diagnostic laboratory. PMID:8287207

Leong, A S

1993-01-01

420

Particle Acceleration Mechanisms  

Microsoft Academic Search

In this paper we review the possible mechanisms for production of non-thermal electrons which are responsible for the observed\\u000a non-thermal radiation in clusters of galaxies. Our primary focus is on non-thermal Bremsstrahlung and inverse Compton scattering,\\u000a that produce hard X-ray emission. We first give a brief review of acceleration mechanisms and point out that in most astrophysical\\u000a situations, and in

V. Petrosian; A. M. Bykov

2008-01-01

421

The Muon Accelerator Program  

SciTech Connect

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

2011-08-01

422

Accelerated predictive-transform  

Microsoft Academic Search

This paper presents a novel accelerated predictive-transform (APT) modeling methodology for use in compression. The APT scheme is illustrated with a monochrome 2D image compression application yielding very promising results. For example, when the Lena image is compressed to 0.056 bits per pixel and the pixel blocks are of dimension 16×16, it is shown that both the design and implementation

Erlan H. Feria; Sos Agaian

2002-01-01

423

Linear induction accelerator  

DOEpatents

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.

1988-06-21

424

Progress of RIBF accelerators  

NASA Astrophysics Data System (ADS)

In order to greatly expand scientific opportunities with radioactive isotope (RI) beams, RIKEN has constructed a new heavy-ion accelerator facility, called "RI Beam Factory (RIBF)." Three new ring cyclotrons with K-values of 570 MeV, 980 MeV, and 2600 MeV, respectively, boost the energies of the output beams from the existing K540-MeV ring cyclotron up to 440 MeV/u for light ions and 345 MeV/u for very heavy ions. These energetic heavy-ion beams are converted into intense radioactive isotope (RI) beams via projectile fragmentation of stable isotopes or in-flight fission of uranium isotopes by a superconducting fragment separator, BigRIPS. The three ring cyclotrons were commissioned in 2006, and RI beams from uranium were first obtained in 2007. The beam intensities and available ion species are increasing at RIBF, owing to the continuous efforts that have been made since the first beam. So far, we have accelerated deuteron, helium, nitrogen, oxygen, aluminum, calcium, zinc, krypton, xenon, and uranium beams with the superconducting ring cyclotron (SRC). The extracted beam intensities reached 1000 pnA for the helium and oxygen beams, and the calcium beam intensity exceeded 400 pnA recently. The intensities of the xenon and uranium beams are also increasing; they reached 24 and 3.6 pnA, respectively. This paper illustrates the construction, commissioning, and various improvements carried out for the RIBF accelerators, as well as the present accelerator performance.

Okuno, H.; Fukunishi, N.; Kamigaito, O.

2012-12-01

425

Frontiers of accelerator instrumentation  

SciTech Connect

New technology has permitted significant performance improvements of established instrumentation techniques including beam position and profile monitoring. Fundamentally new profile monitor strategies are required for the next generation of accelerators, especially linear colliders (LC). Beams in these machines may be three orders of magnitude smaller than typical beams in present colliders. In this paper we review both the present performance levels achieved by conventional systems and present some new ideas for future colliders.

Ross, M.

1992-08-01

426

Oxidised cosmic acceleration  

SciTech Connect

We give detailed proofs of several new no-go theorems for constructing flat four-dimensional accelerating universes from warped dimensional reduction. These new theorems improve upon previous ones by weakening the energy conditions, by including time-dependent compactifications, and by treating accelerated expansion that is not precisely de Sitter. We show that de Sitter expansion violates the higher-dimensional null energy condition (NEC) if the compactification manifold M is one-dimensional, if its intrinsic Ricci scalar R-ring vanishes everywhere, or if R-ring and the warp function satisfy a simple limit condition. If expansion is not de Sitter, we establish threshold equation-of-state parameters w below which accelerated expansion must be transient. Below the threshold w there are bounds on the number of e-foldings of expansion. If M is one-dimensional or R-ring everywhere vanishing, exceeding the bound implies the NEC is violated. If R-ring does not vanish everywhere on M, exceeding the bound implies the strong energy condition (SEC) is violated. Observationally, the w thresholds indicate that experiments with finite resolution in w can cleanly discriminate between different models which satisfy or violate the relevant energy conditions.

Wesley, Daniel H., E-mail: D.H.Wesley@damtp.cam.ac.uk [Centre for Theoretical Cosmology, DAMTP, Cambridge University, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)

2009-01-15

427

Equipartitioning in linear accelerators  

SciTech Connect

Emittance growth has long been a concern in linear accelerators, as has the idea that some kind of energy balance, or equipartitioning, between the degrees of freedom, would ameliorate the growth. M. Prome observed that the average transverse and longitudinal velocity spreads tend to equalize as current in the channel is increased, while the sum of the energy in the system stays nearly constant. However, only recently have we shown that an equipartitioning requirement on a bunched injected beam can indeed produce remarkably small emittance growth. The simple set of equations leading to this condition are outlined below. At the same time, Hofmann, using powerful analytical and computational methods, has investigated collective instabilities in transported beams and has identified thresholds and regions in parameter space where instabilities occur. This is an important generalization. Work that he will present at this conference shows that the results are essentially the same in r-z coordinates for transport systems, and evidence is presented that shows transport system boundaries to be quite accurate in computer simulations of accelerating systems also. Discussed are preliminary results of efforts to design accelerators that avoid parameter regions where emittance is affected by the instabilities identified by Hofmann. These efforts suggest that other mechanisms are present. The complicated behavior of the RFQ linac in this framework also is shown.

Jameson, R.A.

1981-01-01

428

Applications of electrostatic accelerators  

SciTech Connect

Most applications of electrostatic accelerators fit into two main groups, materials analysis and materials modification. Materials analysis includes routine use of Rutherford Backscattering for quality control applications in the semiconductor field. Particle induced x-ray emission (PDCE) is used in fields from art history through environmental sciences. X-ray imaging using 5 MeV DC electron beams and fast pulsed neutron analysis (PFNA) for plastic explosive and drug detection provide promise in the area of security. Accelerator based mass spectrometry (AMS) is having a profound effect in a wide variety of fields which rely on counting extremely rare isotopes in small samples. Materials modification provides a very significant economic impact in the field of semiconductors. Virtually all semiconductor devices now rely on ion implantation with ion beam energies ranging from a few kilovolts to several MeV. With some mention of electron beams, this talk will concentrate primarily on the applications of MeV ion beams from electrostatic accelerators.

Norton, G.A.; Klody, G.M. [National Electrostatics Corp., Middleton, WI (United States)

1995-10-01

429

Cell accelerated cryoablation simulation.  

PubMed

Tumor cryoablation is a clinical procedure where supercooled probes are used to destroy cancerous lesions. Cryoablation is a safe and effective palliative treatment for skeletal metastases, providing immediate and long term pain relief, increasing mobility and improving quality of life. Ideally, lesions are encompassed by an ice ball and frozen to a sufficiently low temperature to ensure cell death. "Lethal ice" is the term used to describe regions within the ice ball where cell death occurs. Failure to achieve lethal ice in all portions of a lesion may explain the high recurrence rate currently observed. Tracking growth of lethal ice is critical to success of percutaneous ablations, however, no practical methods currently exist for non-invasive temperature monitoring. Physicians lack planning tools which provide accurate estimation of the ice formation. Simulation of ice formation, while possible, is computationally demanding and too time consuming to be of clinical utility. We developed the computational framework for the simulation, acceleration strategies for multicore Intel x86 and IBM Cell architectures, and performed preliminary validation of the simulation. Our results demonstrate that the streaming SIMD implementation has better performance and scalability. Both accelerated and non-accelerated algorithms demonstrate good agreement between simulation and manually identified ice ball boundaries in phantom and patient images. Our results show promise for the development of novel cryoablation planning tools with real-time monitoring capability for clinical use. PMID:19854531

Blezek, Daniel J; Carlson, David G; Cheng, Lionel T; Christensen, Jared A; Callstrom, Matthew R; Erickson, Bradley J

2010-06-01

430

Heavy Ion Accelerator (UTI-2).  

National Technical Information Service (NTIS)

The design and test results of the 2 MeV ion accelerator designed for science of materials are described. The UTI-2 accelerator is developed on the basis of the UTI-1 accelerator and equipped with an injector of five-charge ions of iron, chromium and othe...

V. V. Bezuglyj M. Y. Bredikhin B. Il'enko I. M. Nekludov V. K. Knorenko

1986-01-01

431

Exponentially Accelerating Jet in Crossflow  

Microsoft Academic Search

Effects of exponential acceleration on penetration and mixing characteristics of a jet in crossèow have been investigated experimentallyinawatermodel. To imposean exponential acceleration on the èow, both the injection speed and the nozzle width of the jet increased exponentially in the downstream direction of the crossèow. An acceleration parameter ® is deé ned as the ratio of the revolution time of

Adnan Eroglu; Robert E. Breidenthal

1998-01-01

432

New techniques for particle accelerators  

SciTech Connect

A review is presented of the new techniques which have been proposed for use in particle accelerators. Attention is focused upon those areas where significant progress has been made in the last two years--in particular, upon two-beam accelerators, wakefield accelerators, and plasma focusers. 26 refs., 5 figs., 1 tab.

Sessler, A.M.

1990-06-01

433

Progress on Laser Plasma Accelerators.  

National Technical Information Service (NTIS)

Several laser plasma accelerator schemes are reviewed, with emphasis on the Plasma Beat Wave Accelerator (PBWA). Theory indicates that a very high acceleration gradient, of order 1 GeV/m, can exist in the plasma wave driven by the beating lasers. Experime...

P. Chen

1986-01-01

434

Advanced accelerator research at Argonne  

SciTech Connect

A facility with which to experimentally measure methods of advanced acceleration is at the point of completion at Argonne National Laboratory. The new facility consists a system which produces pulse ''doublets'' of energetic electrons, pulse shaping hardware, a space for experimental apparatus, and a high resolution spectrometer. The leading 21 MeV pulse in a doublet can contain up to 15 nano-coulombs of charge and can be adjusted to be from 6 to over 100 pic-seconds in length. The trailing doublet pulse is at 15 MeV, contains about 10/sup 6/ electrons, and can be precisely positioned behind the first from 0 to more than 2000 pico-seconds. This second pulse serves as a probe of fields produced by the intense leading pulse. The initial experimental program includes studies of wake field effects in structures and in plasma. The high resolution of the spectrometer will also make possible measurements of the wakes of various components such as bellows, beam signal pickups, and vacuum connections. Commissioning of the facility is to begin in September, 1986. Tests using cavities and plasma are expected to begin soon thereafter.

Konecny, R.; MacLachlan, J.; Norem, J.; Ruggiero, A.; Schoessow, P.; Simpson, J.

1986-01-01

435

Nighttime Clouds in Martian Arctic (Accelerated Movie)  

NASA Technical Reports Server (NTRS)

An angry looking sky is captured in a movie clip consisting of 10 frames taken by the Surface Stereo Imager on NASA's Phoenix Mars Lander.

The clip accelerates the motion. The images were take around 3 a.m. local solar time at the Phoenix site during Sol 95 (Aug. 30), the 95th Martian day since landing.

The swirling clouds may be moving generally in a westward direction over the lander.

The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

2008-01-01

436

BOOK REVIEW: Electron acceleration in the aurora and beyond  

Microsoft Academic Search

Duncan Bryant is a retired space plasma physicist who spent most of his career at the Rutherford-Appleton Laboratory in Oxfordshire, England. For many years he has been challenging a widely accepted theory, that auroral electrons are accelerated by double layers, on the grounds that it contains a fundamental error (allegedly, an implicit assumption that charged particles can gain energy from

D. Bryant

1999-01-01

437

Durability of concrete—accelerated carbonation and weathering studies  

Microsoft Academic Search

In this paper we report on some laboratory testing on the carbonation and weathering of concrete. Each study involves accelerated test methods. In the carbonation study the effects of humidity level, grade of concrete and pore size on carbonation depths are investigated. Experiments using mechanical and thermal cyclic loading have been carried out to study deterioration of concrete by weathering;

S. K. Roy; K. B. Poh; D. o. Northwood

1999-01-01

438

Accelerator Physics: An Undergraduate Course in Experimental Nuclear Physics  

ERIC Educational Resources Information Center

Discusses a 2-semester-hour experimental physics course utilizing a 0.5 MeV Van de Graaff accelerator. The course requires the completion of six or seven laboratory projects including complete written reports, and theory is emphasized only to the extent needed to understand the projects. (MLH)

Fielder, Douglas S.

1976-01-01

439

Accelerator Mass Spectrometry in Biology and Health Care  

NSDL National Science Digital Library

This video, developed at Lawrence Livermore National Laboratory, describes the instrumentation for accelerator mass spectrometry and its applications. The content describes the instrumentation and its application for carbon dating and measurements of drug distribution. Running time for the video is 49:31.

2011-06-06

440

Cryogenic systems for large superconducting accelerators/storage rings  

SciTech Connect

Particle accelerators and storage rings which utilize superconducting magnets have presented cryogenic system designers, as well as magnet designers, with many new challenges. When such accelerators were first proposed, little operational experience existed to guide the design. Two superconducting accelerators, complete with cryogenic systems, have been designed and are now under construction. These are the Fermilab Doubler Project and the Brookhaven National Laboratory ISABELLE Project. The cryogenic systems which developed at these two laboratories share many common characteristics, especially as compared to earlier cryogenic systems. Because of this commonality, these characteristics can be reasonably taken as also being representative of future systems. There are other areas in which the two systems are dissimilar. In those areas, it is not possible to state which, if either, will be chosen by future designers. Some of the design parameters for the two systems are given.

Brown, D P

1981-01-01

441

Collective Focusing Ion Accelerator  

NASA Astrophysics Data System (ADS)

The principal subject of this dissertation is the trapping and confinement of pure electron plasmas in bumpy toroidal magnetic fields, with particular attention given to the trapping procedure and the behavior of the plasma during the final equilibrium. The most important aspects of the equilibrium which were studied were the qualitative nature of the plasma configuration and motion and its density, distribution, and stability. The motivation for this study was that an unneutralized cloud of electrons contained in a toroidal system, sufficiently dense and stable, may serve to electrostatically focus ions (against centrifugal and self space-charge forces) in a cyclic ion accelerator. Such an accelerator, known as a Collective Focusing Ion Accelerator (C.F.I.A.), could be far smaller than conventional designs (which use external magnetic fields directly to focus the ions) due to the smaller gyro-radius of an electron in a magnetic field of given strength. A toroidal electric field, induced by a changing magnetic flux, would accelerate the ions. To prevent the electrons from being accelerated and shorting out this field (and possibly instigating a two-stream instability), the strength of the toroidal magnetic field which contains the electrons is given spacial periodicity in the toroidal direction. Suitably prepared electrons will not circulate toroidally in such a "bumpy" field due to the mirror effect of the field maxima. These experiments, then, have involved essentially independent electron clouds contained within the magentic "cells" formed by the bumpy field. Supporting experiments performed in a linear mirror system eliminated the complexity of the gradient inherent in a toroidal field and admitted experiments not possible in a torus. These included performing measurements on electrons ejected out one end. Technical developments in injection were also carried out in this simpler system. The electron cloud generally drifted poloidally at a finite radius from the toroidal minor axis. As this would preclude focusing ions with such clouds, damping this motion was investigated. Finite resistance in the normally perfectly conductive vessel wall did this. In further preparation for a working C.F.I.A., additional experiments studied the effect of ions on the stability of the electron cloud.

Goldin, Fletcher Joshua

442

Undulator-Based Laser Wakefield Accelerator Electron Beam Energy Spread and Emittance Diagnostic  

SciTech Connect

The design and current status of experiments to couple the Tapered Hybrid Undulator (THUNDER) to the Lawrence Berkeley National Laboratory (LBNL) laser plasma accelerator (LPA) to measure electron beam energy spread and emittance are presented.

Bakeman, M.S.; Van Tilborg, J.; Nakamura, K.; Gonsalves, A.; Osterhoff, J.; Sokollik, T.; Lin, C.; Robinson, K.E.; Schroeder, C.B.; Toth, Cs.; Weingartner, R.; Gruner, F.; Esarey, E.; Leemans, W.P.

2010-06-01

443

Ionization front accelerator: high gradients, demonstrated particle acceleration, and a proposed relativistic accelerator  

SciTech Connect

The Ionization Front Accelerator (IFA) is a collective ion accelerator for which high-gradient particle acceleration has now been demonstrated. In the IFA, the space charge field at the front of an intense relativistic electron beam is controlled by a laser and used to accelerate an ion bunch. Two complete IFA systems have been built (IFA-1 and IFA-2). Here we present initial IFA-2 ion results that demonstrate that ions have been accelerated with controlled accelerating fields of 33 MV/m over 30 cm. Space charge fields of accelerators like the IFA and the plasma beat wave accelerator are compared, and both are shown to be capable of producing fields 1 GV/m and higher. The IFA systems are discussed and initial IFA-2 ion results are presented. Lastly, a relativistic IFA is proposed that should in principle, permit the attainment of virtually unlimited ion energies. 11 references, 8 figures.

Olson, C.L.; Frost, C.A.; Patterson, E.L.; Anthes, J.P.; Poukey, J.W.

1985-01-01

444

Laser-Driven Proton Beams: Acceleration Mechanism, Beam Optimization, and Radiographic Applications  

Microsoft Academic Search

This paper reviews recent experimental activity in the area of optimization, control, and application of laser-accelerated proton beams, carried out at the Rutherford Appleton Laboratory and the Laboratoire pour lpsilaUtilisation des Lasers Intenses 100 TW facility in France. In particular, experiments have investigated the role of the scale length at the rear of the plasma in reducing target-normal-sheath-acceleration acceleration efficiency.

Marco Borghesi; Carlo Alberto Cecchetti; Toma Toncian; Julien Fuchs; Lorenzo Romagnani; Satyabrata Kar; P. A. Wilson; Patrizio Antici; Patrick Audebert; Erik Brambrink; Ariane Pipahl; Munib Amin; Ralph Jung; Jens Osterholz; Oswald Willi; Wigen Nazarov; Robert J. Clarke; Margaret Notley; David Neely; Patrick Mora; Thomas Grismayer; Guy Schurtz; Angelo Schiavi; Yasuhiko Sentoku

2008-01-01

445

PIC Simulations Laser Wakefield Acceleratrion and Self-Modulated Laser Wakefield Acceleration in Leaky Channels  

Microsoft Academic Search

We present results from one-to-one modeling of proposed laser-plasma accelerator experiments in leaky channels at the L2I laboratory, with enphasis on the comparation between the Laser Wakefield Accelerator (LWFA) regime (tauL ˜= lambda_p) and the Self-Modulated Laser Wakefield Accelerator (SMLWFA) regime (tauL >> lambda_p). Simulations were done using the Osiris Parallel PIC code in 2D with the current operating parameters

R. A. Fonseca; L. O. Silva; W. B. Mori

2002-01-01

446

Drive Beam Shaping and Witness Bunch Generation for the Plasma Wakefield Accelerator  

SciTech Connect

High transformer ratio operation of the plasma wake field accelerator requires a tailored drive beam current profile followed by a short witness bunch. We discuss techniques for generating the requisite dual bunches and for obtaining the desired drive beam profile, with emphasis on the FACET experiment at SLAC National Accelerator Laboratory.

England, R. J.; Frederico, J.; Hogan, M. J. [SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States); Muggli, P. [University of Southern California, Los Angeles, CA 90089 (United States); Joshi, C. [University of California Los Angeles, Los Angeles, CA 90024 (United States)

2010-11-04

447

Drive Beam Shaping and Witness Bunch Generation for the Plasma Wakefield Accelerator  

NASA Astrophysics Data System (ADS)

High transformer ratio operation of the plasma wake field accelerator requires a tailored drive beam current profile followed by a short witness bunch. We discuss techniques for generating the requisite dual bunches and for obtaining the desired drive beam profile, with emphasis on the FACET experiment at SLAC National Accelerator Laboratory.

England, R. J.; Frederico, J.; Hogan, M. J.; Muggli, P.; Joshi, C.

2010-11-01

448

Drive Beam Shaping and Witness Bunch Generation for the Plasma Wakefield Accelerator  

Microsoft Academic Search

High transformer ratio operation of the plasma wake field accelerator requires a tailored drive beam current profile followed by a short witness bunch. We discuss techniques for generating the requisite dual bunches and for obtaining the desired drive beam profile, with emphasis on the FACET experiment at SLAC National Accelerator Laboratory.

R. J. England; J. Frederico; M. J. Hogan; P. Muggli; C. Joshi

2010-01-01

449

On the g/2 Acceleration of a Pulse in a Vertical Chain  

ERIC Educational Resources Information Center

We have frequently enhanced our department's laboratory experiment involving standing transverse waves in a taut horizontal cord. In addition to the standard experiment, students in these labs investigate the surprising concept that the acceleration of a pulse in a chain hanging vertically is a constant and is equal to half the acceleration

Foster, Theodore; van Wyngaarden, Willem; Cary, Arthur; Mottmann, John

2013-01-01

450

Operation and reactivity measurements of an accelerator driven subcritical TRIGA reactor  

Microsoft Academic Search

Experiments were performed at the Nuclear Engineering Teaching Laboratory (NETL) in 2005 and 2006 in which a 20 MeV linear electron accelerator operating as a photoneutron source was coupled to the TRIGA (Training, Research, Isotope production, General Atomics) Mark II research reactor at the University of Texas at Austin (UT) to simulate the operation and characteristics of a full-scale accelerator

David Sean O'Kelly

2008-01-01

451

Preliminary description of the ground test accelerator cryogenic cooling system  

SciTech Connect

The Ground Test Accelerator (GTA) under construction at the Los Alamos National Laboratory is part of the Neutral Particle Beam Program supported by the Strategic Defense Initiative Office. The GTA is a full-sized test facility to evaluate the feasibility of using a negative ion accelerator to produce a neutral particle beam (NPB). The NPB would ultimately be used outside the earth's atmosphere as a target discriminator or as a directed energy weapon. The operation of the GTA at cryogenic temperature is advantageous for two reasons: first, the decrease of temperature caused a corresponding decrease in the rf heating of the copper in the various units of the accelerator, and second, at the lower temperature the decrease in the thermal expansion coefficient also provides greater thermal stability and consequently, better operating stability for the accelerator. This paper discusses the cryogenic cooling system needed to achieve these advantages. 5 figs., 3 tabs.

Edeskuty, F.J.; Stewart, W.F.

1988-01-01

452

Solvent-free cleaning using a centrifugal cryogenic pellet accelerator  

SciTech Connect

An advanced centrifuge that accelerates frozen CO{sub 2} pellets to high speeds for surface cleaning and paint removal is being developed at the Oak Ridge National Laboratory. The centrifuge-based accelerator was designed, fabricated, and tested under a program sponsored by the Warner Robins Air Logistics Center, Robins Air Force Base, Georgia. In comparison to the more conventional compressed air ``sandblast`` pellet accelerators, the centrifugal accelerator system can achieve higher pellet speeds, has precise speed control, and is more than ten times as energy efficient. Furthermore, the use of frozen CO{sub 2} pellets instead of conventional metal, plastic, sand, or other abrasive materials that remain solid at room temperature, minimizes the waste stream. This apparatus has been used to demonstrate cleaning of various surfaces, including removal of paint, oxide coatings, metal coatings, organic coatings, and oil and grease coatings from a variety of surfaces. The design and operation of the apparatus is discussed.

Haines, J.R.; Fisher, P.W.; Foster, C.A.

1995-06-01

453

Dust Accelerators And Their Applications In High-Temperature Plasmas  

NASA Astrophysics Data System (ADS)

The perennial presence of dust in high-temperature plasma and fusion devices has been firmly established. Dust inventory must be controlled, in particular in the next-generation steady-state fusion machines like ITER, as it can pose significant safety hazards and potentially interfere with fusion energy production. Although much effort has been devoted to getting rid of the dust nuisance, there are instances where a controlled use of dust can be beneficial. We have recognized a number of dust-accelerators applications in magnetic fusion, including in plasma diagnostics, in studying dust-plasma interactions, and more recently in edge localized mode (ELM)'s pacing. With the applications in mind, we will compare various acceleration methods, including electrostatic, gas-drag, and plasma-drag acceleration. We will also describe laboratory experiments and results on dust acceleration.

Tico?, C?t?lin M.; Wang, Zhehui

2011-06-01

454

Accelerator R&D: Research for Science - Science for Society  

SciTech Connect

In September 2011 the US Senate Appropriations Committee requested a ten-year strategic plan from the Department of Energy (DOE) that would describe how accelerator R&D today could advance applications directly relevant to society. Based on the 2009 workshop 'Accelerators for America's Future' an assessment was made on how accelerator technology developed by the nation's laboratories and universities could directly translate into a competitive strength for industrial partners and a variety of government agencies in the research, defense and national security sectors. The Office of High Energy Physics, traditionally the steward for advanced accelerator R&D within DOE, commissioned a task force under its auspices to generate and compile ideas on how best to implement strategies that would help fulfill the needs of industry and other agencies, while maintaining focus on its core mission of fundamental science investigation.

The HEP Accelerator R& D Task Force: N.R. Holtkamp,S. Biedron, S.V. Milton, L. Boeh, J.E. Clayton, G. Zdasiuk, S.A. Gourlay, M.S. Zisman,R.W. Hamm, S. Henderson, G.H. Hoffstaetter, L. Merminga, S. Ozaki, F.C. Pilat, M. White

2012-07-01

455

Engineering design of the Saturn accelerator  

SciTech Connect

The Saturn accelerator is a large flash x-ray simulator being constructed as a part of Sandia's Simulation Technology Laboratory. The performance goal of the machine is to provide x-ray exposure capabilities of 5 x 10/sup 12/ rads/s (Si) and 5 cal/g (Au) uniformly distributed over a 500 cm/sup 2/ target area. The operational goal of the machine is to provide this exposure capability reliably in a multiple-shot-a-day mode. This paper will describe the engineering designs which accomplish these goals. This project was a joint effort with Pulse Sciences Inc. personnel performing the conceptual and initial designs, and Sandia National Laboratories personnel performing the final design of the hardware, procurement, manufacturing liaison and the assembly of the machine.

Boyes, J.D.; Cap, J.S.; Douglas, G.M.; Franklin, T.L.; Hart, J.M.; Ives, H.C.; Robischon, S.J.; Smith, B.L.; Stoppkotte, W.O.; VanDeValde, D.M.

1987-01-01

456

Observation of multipactor in an 11.424GHz dielectric-loaded accelerating structure  

Microsoft Academic Search

Summary form only given. A joint Argonne National Laboratory\\/Naval Research Laboratory program is under way to investigate X-band dielectric-loaded accelerating (DLA) structures, using high-power 11.424-GHz radiation from the NRL Magnicon Facility. DLA structures offer the potential of a simple, inexpensive alternative to copper disk-loaded structures for use in high-gradient rf linear accelerators. The purpose of the high-power tests is to

S. H. Gold; W. Gai; J. G. Power; A. K. Kinkead; R. Konecny; C. Jing; W. Liu; Z. M. Yusof

2004-01-01

457

High Power Testing of Dielectric-Loaded Accelerating Structures at 11.424 GHz  

Microsoft Academic Search

Summary form only given. A joint Naval Research Laboratory\\/Argonne National Laboratory study is under way to investigate the performance of X-band dielectric-loaded accelerating (DLA) structures using high-power 11.424-GHz radiation from the NRL Magnicon facility. DLA structures offer the potential of a simple, inexpensive alternative to copper disk-loaded structures for use in high-gradient RF linear accelerators. The purpose of the high-power

S. H. Gold; A. K. Kinkead; Wei Gai; J. G. Power; R. Konecny; Chunguang Jing; Wanming Liu; Z. M. Yusof

2005-01-01

458

Recent Advances in Plasma Acceleration  

SciTech Connect

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

2007-03-19

459

BotEC: Spacecraft Acceleration  

NSDL National Science Digital Library

Question Suppose someone offered you a ride to the nearest star in a new spacecraft that could travel at half the speed of light, or about 150,000 km/second. In order to reach such a cruising speed, you and the spacecraft must accelerate from a standstill to half the speed of light. Acceleration means uncomfortable (and maybe even fatal!) "g" forces, that pressed-into-the-seat feeling you get when a car or airplane accelerates. More than 3 g's of acceleration are tough to take for very long, so your spacecraft's engines are designed to accelerate you at not more than 29 meters/second/second (3 times the acceleration due to gravity at the Earth's surface). How long will it take you and your spacecraft to accelerate to half light speed?

Tewksbury, Barb

460

Project X RFQ EM Design  

SciTech Connect

Project X is a proposed multi-MW proton facility at Fermi National Accelerator Laboratory (FNAL). The Project X front-end would consist of an H- ion source, a low-energy beam transport (LEBT), a CW 162.5 MHz radio-frequency quadrupole (RFQ) accelerator, and a medium-energy beam transport (MEBT). Lawrence Berkeley National Laboratory (LBNL) and FNAL collaboration is currently developing the designs for various components in the Project X front end. This paper reports the detailed EM design of the CW 162.5 MHz RFQ that provides bunching of the 1-10 mA H- beam with acceleration from 30 keV to 2.1 MeV.

Romanov, Gennady; /Fermilab; Hoff, Matthew; Li, Derun; Staples, John; Virostek, Steve; /LBNL

2012-05-09

461

Legionnaires' Disease Laboratory Manual.  

National Technical Information Service (NTIS)

This is a practical working laboratory manual for clinical and environmental microbiology laboratories concerned with the laboratory diagnosis of Legionnaires' disease, or the recovery of Legionella spp. from the environment. Details are given for perform...

P. H. Edelstein

1983-01-01

462

A review of accelerator concepts for the Advanced Hydrotest Facility  

SciTech Connect

The Advanced Hydrotest Facility (AHF) is a facility under consideration by the Department of Energy (DOE) for conducting explosively-driven hydrodynamic experiments. The major diagnostic tool at AHF will be a radiography accelerator having radiation output capable of penetrating very dense dynamic objects on multiple viewing axes with multiple pulses on each axis, each pulse having a time resolution capable of freezing object motion ({approx}50-ns) and achieving a spatial resolution {approx}1 mm at the object. Three accelerator technologies are being considered for AHF by the DOE national laboratories at Los Alamos (LANL), Livermore (LLNL), and Sandia (SNL). Two of these are electron accelerators that will produce intense x-ray pulses from a converter target yielding a dose {approx}1,000--2,000 Rads {at} 1 meter. LLNL has proposed a 16--20 MeV, 3--6 kA linear induction accelerator (LIA) driven by FET-switched modulators driving metglas loaded cavities. SNL has proposed a 12-MeV, 40-kA Inductive Voltage Adder (IVA) accelerator based on HERMES III pulsed power technology. The third option is a 25--50-GeV proton accelerator capable of {approx}10{sup 13} protons/pulse proposed by LANL. This paper will review the current status of the three accelerator concepts for AHF.

Toepfer, A.J. [Science Applications International Corp., Albuquerque, NM (United States)

1998-08-01

463

Two Stage Light Gas Plasma Projectile Accelerator.  

National Technical Information Service (NTIS)

A device for accelerating a projectile to extremely high velocities, composed of a light gas accelerator to impart an initial high velocity to the projectile and a plasma accelerator and compressor receiving the moving projectile and accelerating it to hi...

E. L. Shriver D. W. Jex E. B. Igenbergs

1974-01-01

464

Kinematics: Speed, Velocity & Acceleration  

NSDL National Science Digital Library

The following resource is a NFL sponsored, National Science Foundation funded program intended to teach students about scientific concepts by using the popular sport of Football. Each lesson is accompanied by an informative and fast paced video. In this lesson, students will explore kinematics on the playing field. NSF-funded scientists Tony Schmitz from the University of Florida and John Ziegert of Clemson University explain how the kinematic concepts of position, velocity and acceleration can be used to define how a running back moves.

2010-01-01

465

The relationship between head and neck anthropometry and kinematic response during impact acceleration.  

PubMed

Research on the effects of impact acceleration on the body, primarily the head and neck, has been conducted at the U.S. Naval Biodynamics Laboratory for nearly two decades. Over 150 Navy enlisted men have been subjected to impact acceleration on a sled propelled by a nitrogen-powered horizontal accelerator. Their head and neck kinematic responses during the experimental impact were measured and stored in automated data bases. Similarly, anthropometric measurements were recorded for these subjects. To investigate the relation between head and neck anthropometry and response to impact acceleration, tests involving 15 subjects were selected. A strong relation was found between head and neck anthropometry and linear acceleration of the head along the Z axis. Lesser correlations were determined between the anthropometric measurements and linear acceleration along the X axis and angular acceleration about the Y axis. These findings are potentially applicable to areas such as aircrew selection, physical training and protective equipment development. PMID:1550531

Mawn, S V; Lambert, J J; Catyb, J L

1992-01-01

466

Case study: Accelerated schedule for MULTI LIMS installation  

SciTech Connect

This presentation focuses on the steps taken by the Westinghouse Hanford Company to meet an accelerated schedule for configuration and implementation of the MULTI LIMS in a multiple laboratory environment. The Westinghouse Hanford Company purchased the MULTI LIMS Laboratory Information Management System in August, 1993. Hardware delivery began in October, 1993. Less than four months later, the initial configuration was released for use