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1

A national laboratory funded by the Office of Science of the Department of Energy. www.fnal.gov Fermi National Accelerator Laboratory June 2012  

E-print Network

.fnal.gov Fermi National Accelerator Laboratory June 2012 The Tevatron operated for 28 years at the forefront amount of superconducting wire, it provided the motivation for the expansion of the superconducting wire pioneered new radio-frequency manipulation techniques and developed the first electron-cooling system

Quigg, Chris

2

Fermi National Accelerator Laboratory September 2013 A national laboratory funded by the Office of Science of the Department of Energy. www.fnal.gov  

E-print Network

Fermi National Accelerator Laboratory September 2013 A national laboratory funded by the Office in the next generation of particle accelerators and will spur innovation to meet the challenges of America's future. SRF Accelerator Research & Development R&D for Future Accelerators Superconducting Radio

Quigg, Chris

3

US LHC Accelerator Research Program For the BNL-FNAL-LBNL LHC Accelerator Collaboration  

E-print Network

US LHC Accelerator Research Program Jim Strait For the BNL-FNAL-LBNL LHC Accelerator Collaboration LHC Symposium 3 May 2003 brookhaven - fermilab - berkeley US LHC Accelerator Research Program #12;LHC Symposium - 3 May 03 US LHC Accelerator Research Program - J. Strait 2 Outline Program Goals R&D to Maximize

Large Hadron Collider Program

4

A national laboratory funded by the Office of Science of the Department of Energy. www.fnal.gov Fermi National Accelerator Laboratory February 2014  

E-print Network

better tires, spot suspi- cious cargo, clean up dirty drinking water, help design drugs, discover of superconducting wire for the Tevatron accelerator jump-started this industry Industry: biomedicine and drug

Quigg, Chris

5

A national laboratory funded by the Office of Science of the Department of Energy. www.fnal.gov Fermi National Accelerator Laboratory October 2013  

E-print Network

A national laboratory funded by the Office of Science of the Department of Energy. www pictures of ancient starlight from billions of light years away. Dark Energy Camera By the numbers The Dark Energy Camera's resolution is 570 megapixels, or 570 million pixels. It can see light from up to 8

Quigg, Chris

6

CERN-US July 1, 2004 Accelerator Systems Plan -S.Peggs 1 bnl fnal -lbnl -slac  

E-print Network

CERN-US July 1, 2004 Accelerator Systems Plan - S.Peggs 1 bnl ­ fnal - lbnl - slac US LHC Accelerator Research Program Accelerator Systems Plan S. Peggs, BNL for LARP Accelerator Systems US-CERN Committee, July 1, 2004 #12;CERN-US July 1, 2004 Accelerator Systems Plan - S.Peggs 2 Organization Chart 2

Large Hadron Collider Program

7

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

8

Parameter degeneracies in FNAL-Homestake LBNE setup  

E-print Network

LBNE (Longbaseline Neutrino Oscillation Experiments) provide a powerful experimental setup to study sensitivities and exlcusion limits in neutrino oscillation parameter space. A longbaseline experiment is being planned, at USA, from FNAL (Fermilab National Accelerator Laboratory) to an underground laboratory at Homestake in South Dakota, at an angle of 5.84 degrees from FNAL (at a distance of 1289 km). The prospect of a new beamline towards this location from FNAL, and a 300 Kiloton water Cerenkov detector at the site is in planning stage, for the studies of the neutrino physics program. The long baseline provides sufficient matter effects for neutrino travel, and a large detrecor will help towards better statistics. In this work, we present, upto what extent, the parameter degeneracies, present in oscillation parameter space, can be resolved, using this FNAL-LBNE setup.

Kalpana Bora

2011-11-30

9

Vertical and horizontal test results of 3.9-GHz accelerating cavities at FNAL  

SciTech Connect

The 3rd harmonic 3.9GHz accelerating cavity was proposed to improve the beam performance of the VUV FEL, FLASH. In the frame of a collaborative agreement, Fermilab will provide DESY with a cryomodule containing a string of four cavities. Seven 9-cell Nb cavities were tested and six of them did reach accelerating gradient up to 24 MV/m almost twice more than design value of 14 MV/m. Two of these cavities are with new HOM couplers with improved design. In this paper we present all results of the vertical and horizontal tests.

Khabiboulline, T.; Edwards, H.; Foley, M.; Harms, E.; Hocker, James Andrew; Mitchell, D.; Rowe, A.; Solyak, N.; /Fermilab

2008-06-01

10

LHC Upgrades For the BNL-FNAL-LBNL LHC Accelerator Collaboration  

E-print Network

on and up to design performance quickly. · Improve LHC performance by advances in understanding as a frontier HEP instrument with a timely luminosity upgrade. Advance U.S. Accelerator Science and Technology 7 Why Should We Work on a Luminosity Upgrade? Advance High Energy Physics · Help bring the LHC

Large Hadron Collider Program

11

Fermi National Accelerator Laboratory  

NSDL National Science Digital Library

Fermi National Accelerator Laboratory advances the understanding of the fundamental nature of matter and energy by providing leadership and resources for qualified researchers to conduct basic research at the frontiers of high energy physics and related disciplines. Fermilab's mission is to advance the understanding of the fundamental nature of matter and energy. Fermilab's world-class scientific research facility allows qualified researchers from around the world to conduct fundamental research at the frontiers of high-energy physics and related disciplines.

2009-05-18

12

SLAC National Accelerator Laboratory Accelerator Physics Faculty Search  

E-print Network

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

Ford, James

13

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

14

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

15

FNAL (Fermi National Accelerator Laboratory) Booster Intensity, Extraction, and Synchronization Control for Collider Operation.  

National Technical Information Service (NTIS)

Booster operation for collider physics is considerably different than for fixed target operation. Various scenarios for collider physics, machine studies, and P-Bar targeting may require that the intensity vary from 5E10 PPP to 3E12 PPP at a 15 Hertz mach...

R. J. Ducar, J. R. Lackey, S. R. Tawzer

1987-01-01

16

205:20130828.1126 Dust Accelerator Laboratory  

E-print Network

205:20130828.1126 Dust Accelerator Laboratory Through the Dust Accelerator Laboratory, LASP program Experimental Capabilities With support from the NASA Lunar Science Institute, the Dust Accelerator Laboratory is home to world-class facilities, including the largest dust accelerator in the world

Mojzsis, Stephen J.

17

Ion acceleration in laboratory plasmas  

NASA Technical Reports Server (NTRS)

Recent experiments which investigate ion acceleration in 'collisionless' laboratory plasmas are described. The experiments fall into two classes - those involving stationary and those involving time dependent processes.Among the stationary structures which accelerate ions are sheaths, presheaths, double layers, multiple double layers and ambipolar potentials. RF is an example of time dependent processes. Both classes of experiments are considered. Experiments with 'collisionless' plasmas in multidipole triple plasma-type devices and novel phenomena associated with the use of Ion Cyclotron Resonance Heating in the inhomogeneous magnetic field of a tandem mirror 'fusion' plasma are described. New RF phenomenon include RF pitch angle scattering, RF electron pumping, and ICRF ponderomotive force.

Hershkowitz, Noah

1986-01-01

18

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

19

ICARUS at FNAL  

E-print Network

The INFN and the ICARUS collaboration originally developed the technology of the LAr-TPC. Located the underground LNGS Hall-B, the ICARUS T600 detector has been performed over three years with remarkable detection efficiency featuring a smooth operation, high live time, and high reliability. About 3000 CNGS neutrino events have been collected and are being actively analyzed. ICARUS will now be moved to CERN for an extensive R&D program. The T600 detector will be overhauled and complemented with a similar T150 detector. These improvements are performed in collaboration with the LBNE experiment, of which several INFN Institutions are now members. As a novelty, a SC magnetic field of about 1 T will be introduced. During 2016 it is proposed to move the experiment to FNAL where short base line neutrino beams are available, complementing the approved MicroBooNe experiment which will start operation in 2014. The ICARUS detectors at FNAL will be an important addition since, in absence of anomalies, the signals of several detectors at different distances from the target should be a copy of each other for all experimental signatures. Due to the reduced mass, in MicroBooNE the anti-neutrino signal is too weak for a sensitive comparison. Hence, a definitive clarification of the LSND anomaly requires the exploration of the anti-neutrino signal provided by the much larger T600. The magnetic field will allow separating the anti-neutrino signal from the neutrino-induced background. It is proposed to expose the T600 at the Booster NuBeam at ~700 m from target; the T150 will be located at ~150 m. The T600 will also receive >10^4 nu_e events/year from the off-axis NUMI beam peaked around 1 GeV and exploitable to prepare for the LBNE experiment. The ICARUS teams are also interested in extending the participation to other short baseline neutrino activities collaborating with existing FNAL groups.

M. Antonello; B. Baibussinov; V. Bellini; H. Bilokon; F. Boffelli; M. Bonesini; E. Calligarich; S. Centro; K. Cieslik; D. B. Cline; A. G. Cocco; A. Curioni; A. Dermenev; R. Dolfini; A. Falcone; C. Farnese; A. Fava; A. Ferrari; D. Gibin; S. Gninenko; F. Guber; A. Guglielmi; M. Haranczyk; J. Holeczek; A. Ivashkin; M. Kirsanov; J. Kisiel; I. Kochanek; A. Kurepin; J. Lagoda; F. Mammoliti; S. Mania; G. Mannocchi; V. Matveev; A. Menegolli; G. Meng; G. B. Mills; C. Montanari; F. Noto; S. Otwinowski; T. J. Palczewski; P. Picchi; F. Pietropaolo; P. Plonski; R. Potenza; A. Rappoldi; G. L. Raselli; M. Rossella; C. Rubbia; P. Sala; A. Scaramelli; E. Segreto; D. Stefan; J. Stepaniak; R. Sulej; C. M. Sutera; D. Tlisov; M. Torti; R. G. Van de Water; F. Varanini; S. Ventura; C. Vignoli; H. G. Wang; X. Yang; A. Zani; K. Zaremba

2013-12-27

20

Argonne National Laboratory's Accelerator Experimental Infrastructure  

E-print Network

at ANL The present SRF facility at ANL includes the joint ANL/FNAL superconducting cavity surface test facility comprises a concrete-shielded area for two test cryostats with a dedicated connection for assembly of cryomodules and for cold testing of entire cryomodules. During the past 40 years ANL has

Kemner, Ken

21

SLAC National Accelerator Laboratory Persis Drell, Director  

E-print Network

SLAC National Accelerator Laboratory Persis Drell, Director Mark Reichanadter, Acting COO, Communications J. Williams, CIO S. Porter, Legal Counsel L. Rakow, CFO J. Tarpinian, CSO L. Young, HR M. Wrona ES&H Division J. Tarpinian Computing Division J. Williams Office of the CFO L. Rakow Facilities

Quake, Stephen R.

22

Mu2e Production Target Remote Handling By: Michael R. Campbell, Fermi National Accelerator Laboratory, 6308406495, mikecam@fnal.gov  

E-print Network

/ machine vision + pneumatic extend LVDT locate X,Y,Z coordinates of window and it's mounting bolts Bolt driver in pneumatic extend position Window gripper in pneumatic extend position (with bolt driver in retract position) Spare tool plate Lower ZAxis in full extend position, including 3stage pneumatic

McDonald, Kirk

23

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, Ume University, SE-901 87 Ume (Sweden)] [EISCAT Scientific Association, P.O. Box 812, SE-981 28 Kiruna, Sweden and Department of Physics, Ume University, SE-901 87 Ume (Sweden)

2013-10-15

24

Accelerated laboratory weathering of acrylic lens materials  

NASA Astrophysics Data System (ADS)

Flat samples from various PMMA formulations subjected to accelerated laboratory weathering in an "Atlas Xenotest Alpha +" weathering device operating at 3 Sun irradiance remain transparent after 6.48GJ/m2 radiant exposure (300 - 400nm). Transmittance is reduced and yellowness index increases. However, the amount of change depends largely on the PMMA formulation. Higher UV absorber concentrations lead to smaller changes in optical properties. Based on a model of CPV efficiency for a particular power train, relative losses of efficiency are between 1 and 28%. Performance regarding these properties can be linked to the UV absorber type and concentrations used.

Arndt, Thomas; Richter, Steffen; Kogler, Ren; Pasierb, Mike; Walby, Christopher

2014-09-01

25

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.

26

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

27

Data acquisition for FNAL E665  

SciTech Connect

In this paper 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.

Geesaman, D.F.; Green, M.C.; Kaufman, S.; Tentindo-Repond, S. (Argonne National Lab., IL (USA)); Bartlett, T.F.; Melanson, H.L.; Petravick, D. (Fermi National Accelerator Lab., Batavia, IL (USA)); Michael, D.G. (Harvard Univ., Cambridge, MA (USA)); McLeod, D. (Illinois Univ., Chicago, IL (USA)); Vidal, M. (Max-Planck-Institut fuer Physik und Astrophysik, Muenchen (Germany, F.R.))

1989-10-01

28

RIKEN Nishina Center for Accelerator-Based Science Quantum Hadron Physics Laboratory  

E-print Network

RIKEN Nishina Center for Accelerator-Based Science Quantum Hadron Physics Laboratory Theoretical Laboratory Nuclear Spectroscopy Laboratory High Energy Astrophysics Laboratory Accelerator Group Accelerator Team Detector Team Accelerator Applications Research Group Ion Beam Breeding Team RI Applications Team

Fukai, Tomoki

29

RIKEN Nishina Center for Accelerator-Based Science Quantum Hadron Physics Laboratory  

E-print Network

RIKEN Nishina Center for Accelerator-Based Science Quantum Hadron Physics Laboratory Theoretical Laboratory Nuclear Spectroscopy Laboratory High Energy Astrophysics Laboratory Accelerator Group Accelerator Team Detector Team Accelerator Applications Research Group Radiation Biology Team RI Applications Team

Fukai, Tomoki

30

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

31

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

32

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

33

SLAC National Accelerator Laboratory Experimental Particle Physics Faculty Search  

E-print Network

SLAC National Accelerator Laboratory Experimental Particle Physics Faculty Search The SLAC National Particle Physics in its Particle Physics and Astrophysics (PPA) Directorate. The search is at the tenured of PPA's ongoing programs in experimental particle physics, or to initiate a new program in line with PPA

Wechsler, Risa H.

34

Fermi National Accelerator Laboratory February 2014 Internship opportunities  

E-print Network

Fermi National Accelerator Laboratory February 2014 Internship opportunities Fermilab offers and graduate students. Location Key Dates Fermilab is located 40 miles west of Chicago and is home to seven are provided for some internships. Most internships take place during the summer and last for six to twelve

Quigg, Chris

35

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

36

Laboratory test of Newton's law of gravity for small accelerations  

NASA Astrophysics Data System (ADS)

The rotation curves of spiral galaxies suggest that either a considerable fraction of the galactic mass must be dark matter, or that one of Newton's laws needs revision at accelerations less than 1 {{10}-10} m {{s}-2}. We have endeavored to search for evidence of the latter in a terrestrial laboratory. A sensitive torsion balance was employed to measure small accelerations due to gravity. No deviations from the predictions of Newton's law were found down to 1 10?12 m s?2.

Little, S.; Little, M.

2014-10-01

37

PREFACE: Acceleration and radiation generation in space and laboratory plasmas  

Microsoft Academic Search

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

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

1994-01-01

38

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

39

The cyclotron laboratory and the RFQ accelerator in Bern  

NASA Astrophysics Data System (ADS)

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.; Scampoli, P.; von Bremen, K.; Weber, M.

2013-07-01

40

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

41

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

42

An improved data acquisition system at the Saskatchewan Accelerator Laboratory  

SciTech Connect

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. Experimenters need only write a high-level description of their experiment 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.E. (Univ. of Saskatchewan, Saskatoon (Canada). Saskatchewan Accelerator Lab.)

1994-02-01

43

Control System for the BCP Processing Facility at FNAL.  

National Technical Information Service (NTIS)

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 (BC...

C. Boffo, D. Connolly, L. Elementi, Y. Tereshkin

2003-01-01

44

The scanning electron microscope as an accelerator for the undergraduate advanced physics laboratory  

E-print Network

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 ...

Peterson, Randolph S.

45

Materials Dynamics Laboratory (RIKEN SPring-8 Center) Alfred Baron Mathematical Physics Laboratory (RIKEN Nishina Center for Accelerator-Based Science) Koji Hashimoto  

E-print Network

(RIKEN Nishina Center for Accelerator-Based Science) Koji Hashimoto Strangeness Nuclear Physics Nakagawa Theoretical Nuclear Physics Laboratory (RIKEN Nishina Center for Accelerator-Based ScienceMaterials Dynamics Laboratory (RIKEN SPring-8 Center) Alfred Baron Mathematical Physics Laboratory

Fukai, Tomoki

46

Tiger Team Assessment of the Fermi National Accelerator Laboratory  

SciTech Connect

This draft report documents the Tiger Team Assessment of the Fermi National Accelerator Laboratory (Fermilab) located in Batavia, Illinois. Fermilab is a program-dedicated national laboratory managed by the Universities Research Association, Inc. (URA) for the US Department of Energy (DOE). The Tiger Team Assessment was conducted from May 11 to June 8, 1992, under the auspices of DOE`s Office of Special Projects (OSP) under the Office of the Assistant Secretary for Environment, Safety and Health (EH). The assessment was comprehensive, encompassing environmental, safety and health (ES&H), and quality assurance (QA) disciplines; site remediation; facilities management; and waste management operations. Compliance with applicable Federal , State of Illinois, and local regulations; applicable DOE Orders; best management practices; and internal Fermilab requirements was addressed. In addition, an evaluation of the effectiveness of DOE and Fermilab management of the ES&H/QA and self-assessment programs was conducted. The Fermilab Tiger Team Assessment is part a larger, comprehensive DOE Tiger Team Independent Assessment Program planned for DOE facilities. The objective of the initiative is to provide the Secretary of Energy with information on the compliance status of DOE facilities with regard to ES&H requirements, root causes for noncompliance, adequacy of DOE and contractor ES&H management programs, response actions to address the identified problem areas, and DOE-wide ES&H compliance trends and root causes.

Not Available

1992-06-01

47

Tiger Team Assessment of the Fermi National Accelerator Laboratory  

SciTech Connect

This draft report documents the Tiger Team Assessment of the Fermi National Accelerator Laboratory (Fermilab) located in Batavia, Illinois. Fermilab is a program-dedicated national laboratory managed by the Universities Research Association, Inc. (URA) for the US Department of Energy (DOE). The Tiger Team Assessment was conducted from May 11 to June 8, 1992, under the auspices of DOE's Office of Special Projects (OSP) under the Office of the Assistant Secretary for Environment, Safety and Health (EH). The assessment was comprehensive, encompassing environmental, safety and health (ES H), and quality assurance (QA) disciplines; site remediation; facilities management; and waste management operations. Compliance with applicable Federal , State of Illinois, and local regulations; applicable DOE Orders; best management practices; and internal Fermilab requirements was addressed. In addition, an evaluation of the effectiveness of DOE and Fermilab management of the ES H/QA and self-assessment programs was conducted. The Fermilab Tiger Team Assessment is part a larger, comprehensive DOE Tiger Team Independent Assessment Program planned for DOE facilities. The objective of the initiative is to provide the Secretary of Energy with information on the compliance status of DOE facilities with regard to ES H requirements, root causes for noncompliance, adequacy of DOE and contractor ES H management programs, response actions to address the identified problem areas, and DOE-wide ES H compliance trends and root causes.

Not Available

1992-06-01

48

Laboratory Test of Newton's Second Law for Small Accelerations  

Microsoft Academic Search

We have tested the proportionality of force and acceleration in Newton's second law, F=ma, in the limit of small forces and accelerations. Our tests reach well below the acceleration scales relevant to understanding several current astrophysical puzzles such as the flatness of galactic rotation curves, the Pioneer anomaly, and the Hubble acceleration. We find good agreement with Newton's second law

Brian Woodahl; Jens Gundlach; Stephan Schlamminger; Chris Spitzer; Ki Choi; Jen Coy; Ephraim Fischbach

2009-01-01

49

Laboratory Test of Newton's Second Law for Small Accelerations  

Microsoft Academic Search

We have tested the proportionality of force and acceleration in Newton's second law, F=ma, in the limit of small forces and accelerations. Our tests reach well below the acceleration scales relevant to understanding several current astrophysical puzzles such as the flatness of galactic rotation curves, the Pioneer anomaly, and the Hubble acceleration. We find good agreement with Newton's second law

Brian Woodahl; S. Schlamminger; Chris Spitzer; B. A. Woodahl; Jennifer Coy; Ephraim Fischbach

2007-01-01

50

Laboratory Test of Newton's Second Law for Small Accelerations  

SciTech Connect

We have tested the proportionality of force and acceleration in Newton's second law, F=ma, in the limit of small forces and accelerations. Our tests reach well below the acceleration scales relevant to understanding several current astrophysical puzzles such as the flatness of galactic rotation curves, the Pioneer anomaly, and the Hubble acceleration. We find good agreement with Newton's second law at accelerations as small as 5x10{sup -14} m/s{sup 2}.

Gundlach, J. H.; Schlamminger, S.; Spitzer, C. D.; Choi, K.-Y.; Woodahl, B. A.; Coy, J. J.; Fischbach, E. [Center for Experimental Nuclear Physics and Astrophysics, University of Washington, Seattle, Washington 98195 (United States); Physics Department, Indiana University-Purdue University, Indianapolis, Indiana 46202 (United States); Earth and Space Science Department, Saint Joseph's College, Rensselaer, Indiana 47978 (United States); Physics Department, Purdue University, West Lafayette, Indiana 47907 (United States)

2007-04-13

51

Laboratory test of Newton's second law for small accelerations.  

PubMed

We have tested the proportionality of force and acceleration in Newton's second law, F=ma, in the limit of small forces and accelerations. Our tests reach well below the acceleration scales relevant to understanding several current astrophysical puzzles such as the flatness of galactic rotation curves, the Pioneer anomaly, and the Hubble acceleration. We find good agreement with Newton's second law at accelerations as small as 5 x 10(-14) m/s(2). PMID:17501332

Gundlach, J H; Schlamminger, S; Spitzer, C D; Choi, K-Y; Woodahl, B A; Coy, J J; Fischbach, E

2007-04-13

52

Radition 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

C. W. Jr

2009-01-01

53

Vacuum Systems Consensus Guideline for Department of Energy Accelerator Laboratories  

SciTech Connect

Vacuum vessels, including evacuated chambers and insulated jacketed dewars, can pose a potential hazard to equipment and personnel from collapse, rupture due to back-fill pressurization, or implosion due to vacuum window failure. It is therefore important to design and operate vacuum systems in accordance with applicable and sound engineering principles. 10 CFR 851 defines requirements for pressure systems that also apply to vacuum vessels subject to back-fill pressurization. Such vacuum vessels are potentially subject to the requirements of the American Society of Mechanical Engineers (ASME) Pressure Vessel Code Section VIII (hereafter referred to as the 'Code'). However, the scope of the Code excludes vessels with internal or external operating pressure that do not exceed 15 pounds per square inch gauge (psig). Therefore, the requirements of the Code do not apply to vacuum systems provided that adequate pressure relief assures that the maximum internal pressure within the vacuum vessel is limited to less than 15 psig from all credible pressure sources, including failure scenarios. Vacuum vessels that cannot be protected from pressurization exceeding 15 psig are subject to the requirements of the Code. 10 CFR 851, Appendix A, Part 4, Pressure Safety, Section C addresses vacuum system requirements for such cases as follows: (c) When national consensus codes are not applicable (because of pressure range, vessel geometry, use of special materials, etc.), contractors must implement measures to provide equivalent protection and ensure a level of safety greater than or equal to the level of protection afforded by the ASME or applicable state or local code. Measures must include the following: (1) Design drawings, sketches, and calculations must be reviewed and approved by a qualified independent design professional (i.e., professional engineer). Documented organizational peer review is acceptable. (2) Qualified personnel must be used to perform examinations and inspections of materials, in-process fabrications, non-destructive tests, and acceptance test. (3) Documentation, traceability, and accountability must be maintained for each unique pressure vessel or system, including descriptions of design, pressure conditions, testing, inspection, operation, repair, and maintenance. The purpose of this guideline is to establish a set of expectations and recommendations which will satisfy the requirements for vacuum vessels in general and particularly when an equivalent level of safety as required by 10 CFR 851 must be provided. It should be noted that these guidelines are not binding on DOE Accelerator Laboratories and that other approaches may be equally acceptable in addressing the Part 851 requirements.

Casey,R.; Haas, E.; Hseuh, H-C.; Kane, S.; Lessard, E.; Sharma, S.; Collins, J.; Toter, W. F.; Olis, D. R.; Pushka, D. R.; Ladd, P.; Jobe, R. K.

2008-09-09

54

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

55

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

56

The Accelerator Facility at the Environmental Molecular Sciences Laboratory (EMSL)  

NASA Astrophysics Data System (ADS)

The EMSL, a new Department of Energy (DOE) user facility located at PNNL, will have several state-of-the-art systems, including an accelerator facility that can be used by scientists from around the world. The accelerator facility at EMSL consists of a model 9SDH-2 Pelletron 3.4 MV electrostatic tandem ion accelerator with three beam lines. These beam lines are dedicated to UHV ion scattering capabilities, implantation capabilities, and HV ion scattering capabilities, respectively. The end station attached to the UHV beam line has several electron spectroscopies such as low energy electron diffraction (LEED) and Auger electron spectroscopy (AES) in addition to the ion scattering capabilities. This end station will be interfaced with the EMSL transfer capability that allows a sample to be synthesized, processed, and characterized in several surface science UHV systems. We will discuss the accelerator facility and the capabilities along with some initial results. (Work supported by the DOE/ER/OHER)

Thevuthasan, S.; Peden, C. H. F.; Engelhard, M. H.; Baer, D. R.; Herman, G. S.; Liang, Y.

1997-03-01

57

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

58

PARTICLE ACCELERATION BY THE SUN ''Physics Department & Space Sciences Laboratory, University of California, Berkeley, CA  

E-print Network

in situ observations of solar energetic particles (SEPs) near 1 AU indicate that shock waves driven. INTRODUCTION The Sun is the most energetic particle accelerator in the solar system. In large solar flaresPARTICLE ACCELERATION BY THE SUN R. P. Lin" ''Physics Department & Space Sciences Laboratory

California at Berkeley, University of

59

Fire protection review: revisit No. 2, Fermi National Accelerator Laboratory, Batavia, Illinois  

Microsoft Academic Search

A fire protection survey was conducted at Fermi National Accelerator Laboratory, Batavia, Illinois, on June 17 to 21, 24 to 28, 1985 and November 4 to 8, 1985 to review the facility fire protection program and to make recommendations. A number of improvements have been made in Laboratory fire protection systems since the Fire Protection review of 1977. These include

R. H. Almon; M. W. Earley; R. C. Merritt

1986-01-01

60

Linking Accelerating Laboratory Test with Outdoor Performance Results for a Model Epoxy Coating System  

E-print Network

Linking Accelerating Laboratory Test with Outdoor Performance Results for a Model Epoxy Coating System Xiaohong Gu1 , Brian Dickens1 , Debbie Stanley1 , Walter E. Byrd1 , Tinh Nguyen1 , Iliana Vaca Iowa State University, Ames, IA 50011 1 #12;ABSTRACT Laboratory and outdoor exposure results have been

61

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

62

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

63

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

64

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

65

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

66

Energetic Electrons Accelerated in Solar Particle Events Space Sciences Laboratory, University of Berkeley, CA 94720  

E-print Network

Energetic Electrons Accelerated in Solar Particle Events R. P. Lin Space Sciences Laboratory range of altitudes. For Large Solar Energetic Particle (LSEP, or so-called gradual) events, WIND and ACE/WIND should provide new insights into the origins of energetic solar particles. INTRODUCTION

California at Berkeley, University of

67

LINAC COHERENT LIGHT SOURCE The Linac Coherent Light Source at SLAC National Accelerator Laboratory is  

E-print Network

Photosynthesis in the Act Photosynthesis may be one of the most important chemical reactions on Earth, yet mostLINAC COHERENT LIGHT SOURCE The Linac Coherent Light Source at SLAC National Accelerator Laboratory and the ultrafast pulses required to freeze atomic motions, thus shedding light on the fundamental processes

Wechsler, Risa H.

68

Photo Credit: Peter GinterSLAC National Accelerator Laboratory Dark Energy  

E-print Network

Photo Credit: Peter GinterSLAC National Accelerator Laboratory #12;Dark Energy 70% Dark Matter 26 and Advanced Camera for Surveys #12;Dark Energy 70% Dark Matter 26% Ordinary Matter 4% #12;Dark Energy 70% Dark Matter 26% Ordinary Matter 4% #12;Dark Energy 70% Dark Matter 26% Ordinary Matter 4% #12;Dark Energy 70

Osheroff, Douglas D.

69

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

70

FNAL Proton Source High Intensity Operations and Beam Loss Control  

E-print Network

The 40-year-old Fermilab Proton Source machines, constituted by the Pre-Injector, Linac and the synchrotron Booster, have been the workhorse of the Fermi National Accelerator Laboratory (Fermilab). During this time, the High Energy Physics Program has demanded an increase in proton throughput, especially during the past decade with the beginning of the neutrino program at Fermilab. In order to achieve a successful program, major upgrades and changes were made in Booster. Once again, the Proton Source has been charged to double their beam throughput, while maintain the present residual activation levels, to meet the laboratory Intensity Frontier program goals until new machines are built and operational to replace the Proton Source machines. This paper discusses the present performance of Booster and the plans involved in reaching even higher intensities.

Garcia, F G

2014-01-01

71

Collisionless shocks and particle acceleration in laser-driven laboratory plasmas  

NASA Astrophysics Data System (ADS)

Collisionless shocks are pervasive in space and astrophysical plasmas, from the Earth's bow shock to Gamma Ray Bursters; however, the microphysics underlying shock formation and particle acceleration in these distant sites is not yet fully understood. Mimicking these extreme conditions in laboratory is a grand challenge that would allow for a better understanding of the physical processes involved. Using ab initio multi-dimensional particle-in-cell simulations, shock formation and particle acceleration are investigated for realistic laboratory conditions associated with the interaction of intense lasers with high-energy-density plasmas. Weibel-instability-mediated shocks are shown to be driven by the interaction of an ultraintense laser with overcritical plasmas. In this piston regime, the laser generates a relativistic flow that is Weibel unstable. The strong Weibel magnetic fields deflect the incoming flow, compressing it, and forming a shock. The resulting shock structure is consistent with previous simulations of relativistic astrophysical shocks, demonstrating for the first time the possibility of recreating these structures in laboratory. As the laser intensity is decreased and near-critical density plasmas are used, electron heating dominates over radiation pressure and electrostatic shocks can be formed. The electric field associated with the shock front can reflect ions from the background accelerating them to high energies. It is shown that high quality 200 MeV proton beams, required for tumor therapy, can be generated by using an exponentially decaying plasma profile to control competing accelerating fields. These results pave the way for the experimental exploration of space and astrophysical relevant shocks and particle acceleration with current laser systems.

Fiuza, Frederico

2012-10-01

72

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

73

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

DOE Data Explorer

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

74

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

75

ANL stochastic-cooling experiments using the FNAL 200-MeV cooling ring  

SciTech Connect

Studies of stochastic momentum cooling are being conducted on the FNAL 200-MeV Storage Ring. The specific goal of the activity is to establish confidence in the theory and simulation methods used to describe the cooling process, and to develop techniques and devices suitable for use in the antiproton-accumulation scheme now planned for construction at FNAL. A summary of the activity, including hardware design, results of experiments, comparison with theory, and implications for the antiproton accumulator are presented.

Hogrefe, R.L.; Kellogg, K.D.; Konecny, R.S.; Kramer, S.L.; Simpson, J.D.; Suddeth, D.E.; Hardek, T.W.

1981-01-01

76

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

77

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.

Sols, C.; Chvez, E.; Ortz, M. E.; Andrade, E.

2013-05-01

78

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 Sabtica, and Institute Carnot, is greatly acknowledged.

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

2013-04-01

79

Transverse ion acceleration and ion conic formation in a divergent-field laboratory plasma  

SciTech Connect

The results of laboratory experiments at the University of California at Irvine are presented in which multidimensional ion velocity distributions in the presence of radio-frequency (RF) waves and a spatially divergent external magnetic field are observed. A plasma volume is subjected to either local or nonlocal electrostatic turbulence, which in turn is responsible for accelerating the ions transverse to the confining magnetic field. The ions flow away from the source of turbulence in a spatially decreasing magnetic field, where the {mu} {del}{ital B} force and magnetic-moment conservation work to distort the heated distribution. Laser-induced-fluorescence (LIF) signals, measured downstream from the plasma source with the aid of optical tomography techniques, reveal substantial ion heating and conic formation. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

Zintl, M.; McWilliams, R.; Wolf, N. [Department of Physics, University of California, Irvine, California 92717 (United States)] [Department of Physics, University of California, Irvine, California 92717 (United States)

1995-12-01

80

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

81

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

82

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

Microsoft Academic Search

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

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

2008-01-01

83

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

SciTech Connect

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/m{sup 2} steady-state, 1 GW/m{sup 2} in millisecond transients) and particle fluxes (>10{sup 24} m{sup -2} s{sup -1}) while also undergoing high neutron irradiation (10{sup 18} neutrons/m{sup 2} s). At the Cambridge Laboratory of Accelerator Studies of Surfaces (CLASS), many of the most important issues in plasma-surface interaction research, such as plasma-driven material erosion and deposition, material transport and irradiation and hydrogenic retention are investigated with the use of a 1.7 MV tandem ion accelerator. Ion-Beam Analysis (IBA) is used to investigate and quantify changes in materials due to plasma exposure and ion irradiation is used as a proxy for neutron irradiation to investigate plasma-surface interactions for irradiated materials. This report will outline the capabilities and current research activities at CLASS.

Wright, G. M.; Barnard, H. S.; Hartwig, Z. S.; Stahle, P. W.; Sullivan, R. M.; Woller, K. B.; Whyte, D. G. [Plasma Science and Fusion Center, Massachusettes Institute of Technology, 77 Massachusetts Ave. Cambridge, MA, 02139 (United States)

2011-06-01

84

THE CONTINUOUS ELECTRON BEAM ACCELERATOR FACILITY: CEBAF at the Jefferson Laboratory  

NASA Astrophysics Data System (ADS)

The Jefferson Laboratory's superconducting radiofrequency (srf) Continuous Electron Beam Accelerator Facility (CEBAF) provides multi-GeV continuous-wave (cw) beams for experiments at the nuclear and particle physics interface. CEBAF comprises two antiparallel linacs linked by nine recirculation beam lines for up to five passes. By the early 1990s, accelerator installation was proceeding in parallel with commissioning. By the mid-1990s, CEBAF was providing simultaneous beams at different but correlated energies up to 4 GeV to three experimental halls. By 2000, with srf development having raised the average cavity gradient to 7.5 MV/m, energies up to nearly 6 GeV were routine, at 1-150 A for two halls and 1-100 nA for the other. Also routine are beams of >75% polarization. Physics results have led to new questions about the quark structure of nuclei, and therefore to user demand for a planned 12 GeV upgrade. CEBAF's enabling srf technology is also being applied in other projects.

Leemann, Christoph W.; Douglas, David R.; Krafft, Geoffrey A.

85

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

SciTech Connect

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 stronger archive program by strengthening and appropriately expanding its resources. Among the successful tools in the AHO advocacy portfolio, the Archives Program Review Committee has been the most visible. The Committee and the role it serves as well as other formal and informal advocacy efforts are the focus of this case study My remarks today will begin with a brief introduction to advocacy and outreach as I understand them, and with a description of the Archives and History Office's efforts to understand and work within the corporate culture of the SLAC National Accelerator Laboratory. I will then share with you some of the tools we have employed to advocate for the Archives and History Office programs and activities; and finally, I will talk about how well - or badly - those tools have served us over the past decade.

Deken, Jean Marie; /SLAC

2009-06-19

86

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 Sv 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

87

Ultra-trace analysis of 41Ca in urine by accelerator mass spectrometry: an inter-laboratory comparison  

PubMed Central

A 41Ca interlaboratory comparison between Lawrence Livermore National Laboratory (LLNL) and the Purdue Rare Isotope Laboratory (PRIME Lab) has been completed. Analysis of the ratios assayed by accelerator mass spectrometry (AMS) shows that there is no statistically significant difference in the ratios. Further, Bayesian analysis shows that the uncertainties reported by both facilities are correct with the possibility of a slight under-estimation by one laboratory. Finally, the chemistry procedures used by the two facilities to produce CaF2 for the cesium sputter ion source are robust and don't yield any significant differences in the final result. PMID:24179312

Jackson, George S.; Hillegonds, Darren J.; Muzikar, Paul; Goehring, Brent

2013-01-01

88

Linear induction accelerators at the Los Alamos National Laboratory DARHT facility  

SciTech Connect

The Dual-Axis Radiographic Hydrodynamic Test Facility (DARHT) at Los Alamos National Laboratory consists of two linear induction accelerators at right angles to each other. The First Axis, operating since 1999, produces a nominal 20-MeV, 2-kA single beam-pulse with 60-nsec width. In contrast, the DARHT Second Axis, operating since 2008, produces up to four pulses in a variable pulse format by slicing micro-pulses out of a longer {approx}1.6-microseconds (flat-top) pulse of nominal beam-energy and -current of 17 MeV and 2 kA respectively. Bremsstrahlung x-rays, shining on a hydro-dynamical experimental device, are produced by focusing the electron beam-pulses onto a high-Z target. Variable pulse-formats allow for adjustment of the pulse-to-pulse doses to record a time sequence of x-ray images of the explosively driven imploding mock device. Herein, we present a sampling of the numerous physics and engineering aspects along with the current status of the fully operational dual axes capability. First successful simultaneous use of both the axes for a hydrodynamic experiment was achieved in 2009.

Nath, Subrata [Los Alamos National Laboratory

2010-09-07

89

http://wdrs.fnal.gov/orientation/checklist.pdf DEPARTMENT ORIENTATION CHECKLIST  

E-print Network

http://wdrs.fnal.gov/orientation/checklist.pdf DEPARTMENT ORIENTATION CHECKLIST WEEK #1 ­ WHO, WHAT resources questions , etc. WHAT SHOULD I DO? What should I wear? What should I do four weeks with comments on orientation What if I need to make a personal call or send

Quigg, Chris

90

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

91

Test of a coaxial blade tuner at HTS FNAL  

SciTech Connect

A coaxial blade tuner has been selected for the 1.3GHz SRF cavities of the Fermilab SRF Accelerator Test Facility. Results from tuner cold tests in the Fermilab Horizontal Test Stand are presented. Fermilab is constructing the SRF Accelerator Test Facility, a facility for accelerator physics research and development. This facility will contain a total of six cryomodules, each containing eight 1.3 GHz nine-cell elliptical cavities. Each cavity will be equipped with a Slim Blade Tuner designed by INFN Milan. The blade tuner incorporates both a stepper motor and piezo actuators to allow for both slow and fast cavity tuning. The stepper motor allows the cavity frequency to be statically tuned over a range of 500 kHz with an accuracy of several Hz. The piezos provide up to 2 kHz of dynamic tuning for compensation of Lorentz force detuning and variations in the He bath pressure. The first eight blade tuners were built at INFN Milan, but the remainder are being manufactured commercially following the INFN design. To date, more than 40 of the commercial tuners have been delivered.

Pischalnikov, Y.; Barbanotti, S.; Harms, E.; Hocker, A.; Khabiboulline, T.; Schappert, W.; /Fermilab; Bosotti, A.; Pagani, C.; Paparella, R.; /LASA, Segrate

2011-03-01

92

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

SciTech Connect

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 largest of the water systems found in Pbar is the 95 degree Fahrenheit Low Conductivity Water (LCW) system. LCW is water which has had free ions removed, increasing its resistance to electrical current. This water circuit is used to cool magnets, power supplies, and stochastic cooling components and typically has a resistivity of 11--18 megaohms-cm. For more than ten years the Antiproton rings were plagued with overheating magnets due to plugged water-cooling channels. Various repairs have been tried over the years with no permanent success. Throughout all of this time, water samples have indicated copper oxide, CuO, as the source of the contamination. Matters came to a head in early 1997 following a major underground LCW leak between the Central Utilities Building and the Antiproton Rings enclosures. Over a span of several weeks following system turn-on, some twenty magnets overheated leading to unreliable Pbar source operation. Although it was known that oxygen in the system reacts with the copper tubing to form CuO, work to remedy this problem was not undertaken until this time period. Leaks, large quantities of make-up water, infrequent filter replacement, and thermal cycling also result in an increase in the corrosion product release rate. A three-pronged approach has been implemented to minimize the amount of copper oxide available to plug the magnets: (1) installation of an oxygen removal system capable of achieving dissolved oxygen concentrations in the parts per billion (ppb) range; (2) regular closed-loop filter/flushing of the copper headers and magnets and stainless steel header during down periods; and (3) installation of a full-flow filtration system designed to remove any CuO produced by the trace amounts of dissolved oxygen in the LCW system. All three items have been completed. The dissolved oxygen concentration is now routinely on the order of 15 ppb and returns to that level within 8--12 hours following an upset condition such as a leak. Prior to installation of the oxygen removal system, oxygen levels were approximately 3,000 ppb. Particle analysis of the water before-and-after filter and flushing of the LCW system indicates a cleaner system. Another round of filter/flushing occurred shortly before the scheduled start-up and will be performed during down periods when deemed necessary by newly-installed instrumentation. The full-flow filtration system has been recently commissioned. The system consists of two parallel filter housings, with a rated total flow capacity of 2,500 gpm at 300 psi, piping to the LCW supply header and associated instrumentation.

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

2000-05-10

93

Profile Monitor SEM's for the NuMI Beam at FNAL  

E-print Network

The Neutrinos at the Main Injector (NuMI) project will extract 120 GeV protons from the FNAL Main Injector in 8.56usec spills of 4E13 protons every 1.9 sec. We have designed secondary emission monitor (SEM) detectors to measure beam profile and halo along the proton beam transport line. The SEM?s are Ti foils 5um in thickness segmented in either 1?mm or 0.5?mm pitch strips, resulting in beam loss ~5E-6. We discuss aspects of the mechanical design, calculations of expected beam heating, and results of a beam test at the 8 GeV transport line to MiniBoone at FNAL.

D. Indurthy; S. Kopp; Z. Pavlovich; M. Proga

2004-05-05

94

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

95

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

96

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

97

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

Microsoft Academic Search

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

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

2010-01-01

98

DEVELOPMENT OF A HIGH BRIGHTNESS ELECTRON GUN FOR THE ACCELERATOR TEST FACILITY AT BROOKHAVEN NATIONAL LABORATORY*  

E-print Network

954 DEVELOPMENT OF A HIGH BRIGHTNESS ELECTRON GUN FOR THE ACCELERATOR TEST FACILITY AT BROOKHAVEN, New York 11973 and K. McDonald Princeton [Jniversity Abstract An electron gun utilizing a radio). Here we report on the de;$n of the electron gun which will provide r.f. bunches of up to 10 electrons

McDonald, Kirk

99

CLAIRE - A Novel Nuclear Astrophysics Accelerator Facility at the Lawrence Berkeley National Laboratory  

Microsoft Academic Search

CLAIRE (Center for Low Energy Astrophysics and Interdisciplinary REsearch) is a proposed nuclear astrophysics accelerator facility to be built at the 88-Inch Cyclotron at LBNL. Its primary goal will be to measure cross sections relevant to stellar burning. In particular, our focus is to build a facility powerful enough to measure the ^3He(^4He, gamma)^7Be cross section near the Gamov peak.

Daniela Leitner; Damon Todd; Paul Vetter; Matthaeus Leitner; Reina Maruyama; Kevin Nan Xu

2006-01-01

100

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

101

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

102

Rapid estimation of lives of deficient superpave mixes and laboratory-based accelerated mix testing models  

NASA Astrophysics Data System (ADS)

The engineers from the Kansas Department of Transportation (KDOT) often have to decide whether or not to accept non-conforming Superpave mixtures during construction. The first part of this study focused on estimating lives of deficient Superpave pavements incorporating nonconforming Superpave mixtures. These criteria were based on the Hamburg Wheel-Tracking Device (HWTD) test results and analysis. The second part of this study focused on developing accelerated mix testing models to considerably reduce test duration. To accomplish the first objective, nine fine-graded Superpave mixes of 12.5-mm nominal maximum aggregate size (NMAS) with asphalt grade PG 64-22 from six administrative districts of KDOT were selected. Specimens were prepared at three different target air void levels Ndesign gyrations and four target simulated in-place density levels with the Superpave gyratory compactor. Average number of wheel passes to 20-mm rut depth, creep slope, stripping slope, and stripping inflection point in HWTD tests were recorded and then used in the statistical analysis. Results showed that, in general, higher simulated in-place density up to a certain limit of 91% to 93%, results in a higher number of wheel passes until 20-mm rut depth in HWTD tests. A Superpave mixture with very low air voids Ndesign (2%) level performed very poorly in the HWTD test. HWTD tests were also performed on six 12.5-mm NMAS mixtures with air voids Ndesign of 4% for six projects, simulated in-place density of 93%, two temperature levels and five load levels with binder grades of PG 64-22, PG 64-28, and PG 70-22. Field cores of 150-mm in diameter from three projects in three KDOT districts with 12.5-mm NMAS and asphalt grade of PG 64-22 were also obtained and tested in HWTD for model evaluation. HWTD test results indicated as expected. Statistical analysis was performed and accelerated mix testing models were developed to determine the effect of increased temperature and load on the duration of the HWTD test. Good consistency between predicted and observed test results was obtained when higher temperature and standard load level were used. Test duration of the HWTD can thus be reduced to two hours or less using accelerated mix testing (statistical) models.

Manandhar, Chandra Bahadur

103

Status of the darht 2nd axis accelerator at the Los Alamos national laboratory  

Microsoft Academic Search

The Dual Axis Radiographic Hydrodynamic Test Facility (DARHT) was constructed at Los Alamos National Laboratory as a radiographic facility to provide dual-axis multi-time radiography to support the US Stockpile Stewardship Program. The DARHT 1st Axis has been operational since 1999 and has been providing excellent radiographs. The DARHT 2nd Axis construction project was completed in early 2003. However, during the

R. D. Scarpetti?; S. Nath; J. Barraza; C. A. Ekdahl; E. Jacquez; B. T. McCuistian; K. Nielsen; M. Schulze; J. Seitz; G. J. Caporaso; Y.-J. Chen; G. Logan; F. Bieniosek

2007-01-01

104

Stunt Barbie - A Laboratory Practicum Combining Constant Velocity and Constant Acceleration  

NASA Astrophysics Data System (ADS)

In preparing to teach the advanced physics course at my high school, I found it useful to work through the end-of-chapter problems in the book used by the advanced class. A problem on motion in one dimension involved a stunt woman in free fall from a tree limb onto a horse running beneath her.2 The problem presents a connected learning opportunity for students because it requires the use of the constant velocity model xf = v*t + xi and the constant acceleration model yf = * g* t2 + vyi* t + yi (where g = 9.8 m/s/s) to solve it. I named the stunt woman Barbie and created an activity titled "Stunt Barbie."

Hertting, Scott

2011-04-01

105

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

106

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

107

US-LARP Progress on LHC IR Upgrades Tanaji Sen, John Johnstone, Nikolai Mokhov, FNAL, Batavia, IL 60510  

E-print Network

US-LARP Progress on LHC IR Upgrades Tanaji Sen, John Johnstone, Nikolai Mokhov, FNAL, Batavia, IL the progress on LHC IR upgrades made by the US-LARP collaboration since the last CARE meeting in November 2004 the luminosity in the LHC will require upgrades to the interaction regions (IRs) as well as to the injector chain

Sen, Tanaji

108

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

109

Current and Planned High Proton Flux Operations at the FNAL Booster  

E-print Network

The Fermilab Proton Source machines, constituted by Pre-Injector, conventional Linac and Booster synchrotron, at Fermi National Accelerator Laboratory (Fermilab) had have a long history of successful beam operations. Built in late '60s, the Fermilab Proton Source began operations early in the '70s and since then it has successful provided protons to support the laboratory physics experiments. During the past decade, Booster performance reached unprecedented proton flux delivery of the order of 1.0-1.1E17 protons per hour, corresponding to 40 kW of beam power while maintained an allowed upper limit of 525 W of beam loss in the tunnel. In order to achieve this historical performance, major hardware upgrades were made in the machine combined with improvements in beam orbit control and operational awareness. Once again, the Proton Source has been charged to double their beam throughput, while maintaining the present residual activation levels, to meet the laboratory Intensity Frontier program goals until new mach...

Garcia, F G

2014-01-01

110

Do you want to build such a machine? : Designing a high energy proton accelerator for Argonne National Laboratory.  

SciTech Connect

Argonne National Laboratory's efforts toward researching, proposing and then building a high-energy proton accelerator have been discussed in a handful of studies. In the main, these have concentrated on the intense maneuvering amongst politicians, universities, government agencies, outside corporations, and laboratory officials to obtain (or block) approval and/or funds or to establish who would have control over budgets and research programs. These ''top-down'' studies are very important but they can also serve to divorce such proceedings from the individuals actually involved in the ground-level research which physically served to create theories, designs, machines, and experiments. This can lead to a skewed picture, on the one hand, of a lack of effect that so-called scientific and technological factors exert and, on the other hand, of the apparent separation of the so-called social or political from the concrete practice of doing physics. An exception to this approach can be found in the proceedings of a conference on ''History of the ZGS'' held at Argonne at the time of the Zero Gradient Synchrotron's decommissioning in 1979. These accounts insert the individuals quite literally as they are, for the most part, personal reminiscences of those who took part in these efforts on the ground level. As such, they are invaluable raw material for historical inquiry but generally lack the rigor and perspective expected in a finished historical work. The session on ''Constructing Cold War Physics'' at the 2002 annual History of Science Society Meeting served to highlight new approaches circulating towards history of science and technology in the post-WWII period, especially in the 1950s. There is new attention towards the effects of training large numbers of scientists and engineers as well as the caution not to equate ''national security'' with military preparedness, but rather more broadly--at certain points--with the explicit ''struggle for the hearts and minds of men.'' There is a call for greater detail in periodization as events such as Stalin's death and Khruschev's subsequent speech, the end of the Korean conflict, the hydrogen bomb test, Eisenhower's Atoms for Peace initiative, the 1955 Geneva conference, and Sputnik each served to drastically change the landscape in the United States. Furthermore, Harvard University Press recently published the first detailed and scholarly account of a history of the national laboratories; the work argues that the ''systemicity'' of the organization must be considered as a necessary piece when examining any of the myriad of related puzzles.

Paris, E.

2004-04-05

111

Electron-Cloud Build-Up Simulations for the FNAL Main Injector  

SciTech Connect

We present a summary on ongoing simulation results for the electron-cloud (EC) buildup in the context of the proposed FNAL Main Injector (MI) intensity upgrade effort [1]. Most of the results presented here are for the field-free region at the location of the retarding field analyzer (RFA) electron detector [2-4]. The primary input variable we exercise is the peak secondary electron yield (SEY) {delta}{sub max}, which we let vary in the range 1.2 {le} {delta}{sub max} {le} 1.7. By combining our simulated results for the electron flux at the vacuum chamber wall with the corresponding RFA measurements we infer that 1.25 {approx}< {delta}{sub max} {approx}< 1.35 at this location. From this piece of information we estimate features of the EC distribution for various fill patterns, including the average electron number density n{sub e}. We then compare the behavior of the EC for a hypothetical RF frequency f{sub RF} = 212 MHz with the current 53 MHz for a given total beam population N{sub tot}. The density n{sub e} goes through a clear threshold as a function of N{sub tot} in a field-free region. As expected, the higher frequency leads to a weaker EC effect: the threshold in N{sub tot} is a factor {approx} 2 higher for f{sub RF} = 212 MHz than for 53 MHz, and ne is correspondingly lower by a factor {approx} 2 when N{sub tot} is above threshold. We briefly describe further work that needs to be carried out, sensitivities in the calculation, and puzzles in the results that remain to be addressed.

Furman, Miguel .A.

2008-08-25

112

Study of new FNAL-NICADD extruded scintillator as active media of large EMCal of ALICE at LHC  

SciTech Connect

The current conceptual design of proposed Large EMCal of ALICE at LHC is based largely on the scintillating mega-tile/fiber technology implemented in CDF Endplug upgrade project and in both barrel and endcap electromagnetic calorimeters of the STAR. The cost of scintillating material leads us to the choice of extruded polystyrene based scintillator, which is available in new FNAL-NICADD facility. Result of optical measurements, such as light yield and light yield variation, show that it is possible to use this material as active media of Large EMCal of ALICE at LHC.

Oleg A. Grachov et al.

2004-05-04

113

World Pendulum--A Distributed Remotely Controlled Laboratory (RCL) to Measure the Earth's Gravitational Acceleration Depending on Geographical Latitude  

ERIC Educational Resources Information Center

We suggest that different string pendulums are positioned at different locations on Earth and measure at each place the gravitational acceleration (accuracy [delta]g is approximately equal to 0.01 m s[superscript -2]). Each pendulum can be remotely controlled via the internet by a computer located somewhere on Earth. The theoretical part describes

Grober, S.; Vetter, M.; Eckert, B.; Jodl, H.-J.

2007-01-01

114

On the possibility of laboratory shock wave studies of the equation of state of a material at gigabar pressures with beams of laser-accelerated particles  

NASA Astrophysics Data System (ADS)

The possibility of laboratory shock wave studies of the equation of state of a material with beams of laser-accelerated charged particles at pressures an order of magnitude higher than those reached in current experiments has been discussed. The possibility of the generation of a plane quasistationary shock wave with a pressure of several gigabars behind its front at the irradiation of a target by a laser beam with an energy of several kilojoules and an intensity of about 1017 W/cm2, which is accompanied by the generation of fast electrons with an average energy of 20-50 keV, has been justified.

Gus'kov, S. Yu.

2014-09-01

115

Model-free estimation of outdoor performance of a model epoxy coating system using accelerated test laboratory data  

Microsoft Academic Search

Laboratory and field exposure results for thin transparent films of a model epoxy coating system have been successfully linked\\u000a using both dosage and dose, assuming only that the additivity law and the reciprocity law are valid. This paper describes\\u000a the technique used in the linkage step. Laboratory exposures were carried out on the National Institute of Standards and Technology\\u000a (NIST)

Brian Dickens

2009-01-01

116

Accelerating technology transfer from federal laboratories to the private sector by industrial R and D collaborations - A new business model  

SciTech Connect

Many important products and technologies were developed in federal laboratories and were driven initially by national needs and for federal applications. For example, the clean room technology that enhanced the growth of the semiconductor industry was developed at Sandia National Laboratories (SNL) decades ago. Similarly, advances in micro-electro-mechanical-systems (MEMS)--an important set of process technologies vital for product miniaturization--are occurring at SNL. Each of the more than 500 federal laboratories in the US, are sources of R and D that contributes to America's economic vitality, productivity growth and, technological innovation. However, only a fraction of the science and technology available at the federal laboratories is being utilized by industry. Also, federal laboratories have not been applying all the business development processes necessary to work effectively with industry in technology commercialization. This paper addresses important factors that federal laboratories, federal agencies, and industry must address to translate these under utilized technologies into profitable products in the industrial sector.

LOMBANA,CESAR A.; ROMIG JR.,ALTON D.; LINTON,JONATHAN D.; MARTINEZ,J. LEONARD

2000-04-13

117

First electrons from the new 220 TW Frascati Laser for Acceleration and Multidisciplinary Experiments (FLAME) at Frascati National Laboratories (LNF)  

NASA Astrophysics Data System (ADS)

A new era of laser based plasma accelerators is emerging following the commissioning of many high power laser facilities around the world. Extremely short (tens of fs) laser pulses with energy of multi-joules level are available at these newly built facilities. Here we describe the new 220 TW FLAME facility. In particular we discuss the laser system general layout, the main measurements on the laser pulse parameters, the underground target area. Finally we give an overview of the first results of the Self-Injection Test Experiment (SITE), obtained at a low laser energy. This initial low laser energy experimental campaign was necessary for the validation of the radio-protection shielding (Esposito, 2011 [1]) we discuss here. With respect to our preliminary configuration, with a pulse duration of 30 fs and a focusing optic of F/15, we discuss here the minimum laser energy requirements for electron acceleration and the forward transmitted optical radiation.

Levato, T.; Calvetti, M.; Anelli, F.; Batani, D.; Benocci, R.; Cacciotti, L.; Cecchetti, C. A.; Cerafogli, O.; Chimenti, P.; Clozza, A.; Drenska, N.; Esposito, A.; Faccini, R.; Fioravanti, S.; Gamucci, A.; Gatti, C.; Giulietti, A.; Giulietti, D.; Labate, L.; Lollo, V.; Martellotti, S.; Monteduro, M.; Pace, E.; Pathak, N. C.; Pellegrino, L.; Piastra, F.; Pistoni, M.; Di Pirro, G.; Di Raddo, R.; Rotundo, U.; Ricci, R.; Richetta, M.; Vaccarezza, C.; Valente, P.; Gizzi, L. A.

2013-08-01

118

Investigation of the effects of acid rain on the deterioration of cement concrete using accelerated tests established in laboratory  

Microsoft Academic Search

Deterioration of cement concrete specimens caused by simulated acid rain was investigated by laboratory tests. Before and after cement concrete specimens were exposed to simulated acid rain, the neutralized depth, the compressive strength and the chemical compositions in the hardened cement paste were measured. The mineralogical composition of the concrete specimens was analyzed with XRD. The results lead to the

Shaodong Xie; Li Qi; Ding Zhou

2004-01-01

119

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

120

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

121

Studies of E-Cloud Build up for the FNAL Main Injector and for theLHC  

SciTech Connect

We present a summary of recent simulation studies of the electron-cloud (EC) build-up for the FNAL MI and for the LHC. In the first case we pay particular attention to the dependence on bunch intensity N{sub b} at injection energy assuming the nominal bunch spacing t{sub b} = 19 ns, and we focus on the dipole magnets and field-free regions. The saturated value of the average EC density shows a clear threshold in N{sub b} beyond which the beam will be approximately neutralized on average. For the case of the LHC we limit our discussion to arc dipoles at collision energy, and bunch spacings t{sub b} = 25 ns or t{sub b} = 75 ns. The main variables exercised in this study are N{sub b} and the peak value of the secondary emission yield (SEY) {delta}{sub max}. For t{sub b} = 25 ns we conclude that the EC power deposition is comfortably below the available cooling capacity of the cryogenic system if {delta}{sub max} is below {approx} 1.2 at nominal N{sub b}. For t{sub b} = 75 ns, the EC power deposition is insignificant. As a byproduct of this exercise, we reach a detailed understanding of the significant role played by the backscattered secondary electrons. This article summarizes the results, an slightly extends the discussions, presented in Refs. 1 and 2.

Furman, M.A.

2006-06-14

122

Mitigation Plans for the Microbunching-Instability-Related COTR at ASTA/FNAL  

SciTech Connect

At the Advanced Superconducting Test Accelerator (ASTA) now under construction at Fermilab, we anticipate the appearance of the microbunching instability related to the longitudinal space charge (LSC) impedances. With a photoinjector source and up to two chicane compressors planned, the conditions should result in the shift of some microbunched features into the visible light regime. The presence of longitudinal microstructures (microbunching) in the electron beam or the leading edge spikes can result in strong, spatially localized coherent enhancements of optical transition radiation (COTR) that mask the actual beam profile. Several efforts on mitigation of the effects in the diagnostics task have been identified. At ASTA we have designed the beam profiling stations to have mitigation features based on spectral filtering, scintillator choice, and the timing of the trigger to the digital camera's CCD chip. Since the COTR is more intense in the NIR than UV we have selectable bandpass filters centered at 420 nm which also overlap the spectral emissions of the LYSO:Ce scintillators. By delaying the CCD trigger timing of the integration window by 40-50 ns, we can reject the prompt OTR signal and integrate on the delayed scintillator light predominately. This combination of options should allow mitigation of COTR enhancements of order 100-1000 in the distribution.

Lumpkin, A. H.; Johnson, A. M.

2013-05-01

123

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

124

Staged laser plasma accelerators  

NASA Astrophysics Data System (ADS)

We present current results on staged electron acceleration in the LOASIS program at the Lawrence Berkeley National Laboratory. The goal is to experimentally demonstrate laser driven electron acceleration in two stages, where each stage is driven by a separate laser pulse. This technology could provide the key to built compact laser driven accelerators which could potentially reach up to TeV in electron energy.

Sokollik, Thomas; Shiraishi, Satomi; Shaw, Brian; Gonsalves, Antony; Nakamura, Kei; van Tilborg, Jeroen; Esarey, Eric; Schroeder, Carl B.; Benedetti, Carlo; Toth, Csaba; Leemans, Wim

2012-12-01

125

Strong ground motion data recorded at the Idaho National Laboratory during the 1983 Borah Peak, Idaho earthquake. [Appendix contains plot generated by accelerogram showing peak valves amplitude, response spectra, displacement, veolocity and acceleration  

Microsoft Academic Search

The Idaho National Engineering Laboratory (INEL) is located approximately 80 km southeast of the epicenter for the 1983 M{sub S} 7.3 Borah Peak Idaho earthquake. Thirteen strong-motion accelerographs located at various facilities around the INEL Site recorded strong-ground motions from the Borah Peak earthquake. The strong-motion records were digitized and processed resulting in corrected acceleration, velocity, and displacement time-histories and

S. M. Jackson; J. J. King; D. M. Anderson; G. S. Carpenter; H. A. Adams

1991-01-01

126

SLAC Accelerator R&D Strategic Plan  

E-print Network

SLAC Accelerator R&D Strategic Plan Tor Raubenheimer SLAC SPC Meeting May 7th, 2010 #12;Outline Page 3 SLAC Accelerator Research · SLAC is largely focused on accelerator-based research ­ SLAC accelerator research is key to the future of the laboratory · Accelerator R&D focused on advancing operating

Wechsler, Risa H.

127

Linear Accelerators  

NASA Astrophysics Data System (ADS)

In linear accelerators the particles are accelerated by either electrostatic fields or oscillating Radio Frequency (RF) fields. Accordingly the linear accelerators are divided in three large groups: electrostatic, induction and RF accelerators. Overview of the different types of accelerators is given. Stability of longitudinal and transverse motion in the RF linear accelerators is briefly discussed. The methods of beam focusing in linacs are described.

Sidorin, Anatoly

2010-01-01

128

Laser accelerators  

NASA Astrophysics Data System (ADS)

Laser accelerators are characterized, by their mode of operation, into media, far field, and near field accelerators. The first category, media accelerators, include the inverse Cherenkov effect accelerator, the plasma focus accelerator, and the beat wave accelerator (BWA). The second category, far field accelerators, include the two wave device and the inverse free electron accelerator (IFEI). The third category, near field accelerators, includes conventional linac scaled to small dimensions, dielectric sheets, small holes in dielectric cylinders, and gratings. An example from each category is given; namely: (1) the BWA; (2) the IFEL; and (3) the linac scaled to small dimensions and powered by a free electron laser (FEL). Grating accelerators are also discussed.

Sessler, A.

1983-04-01

129

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

130

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

E-print Network

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

Wechsler, Risa H.

131

Electrothermal accelerators  

SciTech Connect

In electrothermal (ET) guns, the projectile acceleration is governed by gas dynamics as in explosively-driven guns. In a conventional gun, however, both the energy for heating and the material to be heated are contained in the solid propellant. Electrothermal launchers allow an external electric power supply to be used to provide the necessary energy; hence, lower atomic weight propellants may be used and heated to higher temperatures while maintaining a tailored acceleration profile. Important improvements in hypervelocity performance and barrel degradation can be obtained by controlling the electric discharges via power conditioning. Complex voltage and current waveforms are achieved using complex power conditioning systems, since the existing power supplies do not conform to ET gun requirements. This paper advances the concept of a single element power supply for ET guns, showing that compulsator-type machines with waveform flexibility (pulse shaping capability) can satisfy all the ET gun power supply and conditioning requirements while maintaining a high efficiency and los mass. Additionally, compulsators are suitable for repetitive-fire applications. Also described in the paper is a system of homopolar generators (HPGs) and inductors for laboratory applications.

Driga, M.D.; Ingram, M.W.; Weldon, W.F. (Texas Univ., Austin, TX (USA). Center for Electromechanics)

1989-01-01

132

Breakthrough: Fermilab Accelerator Technology  

SciTech Connect

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

None

2012-04-23

133

Diagnostics for Laser Accelerators  

SciTech Connect

This tutorial paper discusses, at a basic level, some of the diagnostics used in plasma accelerators laboratories. Covered are measurements of laser beams, using probe laser beams to characterize the plasma itself (as opposed to the plasma wave accelerating structure) in various ways, including density fluctuations in the plasma and also static or near-static density structures in the plasma. Also covered are laser probe techniques that are especially suitable for studying the properties of the relativistic electron plasma wave that is ultimately the particle accelerator.

Clayton, C.E. [Department of Electrical Engineering, University of California at Los Angeles, 66-127E Engineering IV Bldg., Los Angeles, CA 90095 (United States)

2004-12-07

134

Strong ground motion data recorded at the Idaho National Laboratory during the 1983 Borah Peak, Idaho earthquake. [Appendix contains plot generated by accelerogram showing peak valves amplitude, response spectra, displacement, veolocity and acceleration  

SciTech Connect

The Idaho National Engineering Laboratory (INEL) is located approximately 80 km southeast of the epicenter for the 1983 M{sub S} 7.3 Borah Peak Idaho earthquake. Thirteen strong-motion accelerographs located at various facilities around the INEL Site recorded strong-ground motions from the Borah Peak earthquake. The strong-motion records were digitized and processed resulting in corrected acceleration, velocity, and displacement time-histories and response and Fourier spectra. Peak horizontal accelerations had a range of 0.022 to 0.078 g for accelerographs located at free-field and basement sites. Values of 0.037 {minus} 0.817 g were recorded at accelerographs located within structures above basement level. Peak vertical accelerations ranged from 0.16 (basement level) to 0.059 g (top of structures). The peak amplitudes of the response and Fourier Spectra occur in the 2 -- 10 hz frequency range. Appendices include Borah Peak earthquake accelerograph data printouts. 8 refs., 4 figs., 7 tabs.

Jackson, S.M.; King, J.J.; Anderson, D.M.; Carpenter, G.S.; Adams, H.A.

1991-06-01

135

Lawrence Berkeley Laboratory Institutional Plan FY 1987-1992  

E-print Network

Light Ion Biomedical Research Accelerator Lawrence Livermore National Laboratory Laboratori Nazionali di Frascati Multiple-Beam Experiment Multiprogram Energy Laboratory Facilities Support Magnetic Fusion

Various

1986-01-01

136

Fermilab Today http://www.fnal.gov/pub/today/ 1 of 3 8/30/2006 10:13 AM  

E-print Network

.m. Accelerator Physics and Technology Seminar - 1 West Speaker: J. Peters, DESY Title: The History of H-Star, there is a small probability that the ball will end up in the outfield. This concept is particularly important when quiet hours spent in deep thought. Coupled with the fact that he is apparently not playing the game

Toback, David

137

Android Acceleration  

NSDL National Science Digital Library

Students prepare for the associated activity in which they investigate acceleration by collecting acceleration vs. time data using the accelerometer of a sliding Android device. Based on the experimental set-up for the activity, students form hypotheses about the acceleration of the device. Students will investigate how the force on the device changes according to Newton's Second Law. Different types of acceleration, including average, instantaneous and constant acceleration, are introduced. Acceleration and force is described mathematically and in terms of processes and applications.

IMPART RET Program, College of Information Science & Technology,

138

Muon g-2 Experiment A national laboratory funded by the Office of Science of the Department of Energy. www.fnal.gov  

E-print Network

g-2 experiment will come in, conducting a next-generation experiment with much greater precision the same electrical charge (negative) as an electron. They exist for only about 2.2 millionths of a second is a particle storage ring made of steel, aluminum and superconducting wire. It measures 50 feet in diameter

Quigg, Chris

139

Ion Acceleration by Beating Electrostatic Waves: Domain of Allowed Acceleration  

E-print Network

for propulsion applications stems from its capability of energizing ions from arbitrarily low initial velocityIon Acceleration by Beating Electrostatic Waves: Domain of Allowed Acceleration R. Spektor and E.Y. Choueiri Electric Propulsion and Plasma Dynamics Laboratory (EPPDyL) Mechanical and Aerospace Engineering

Choueiri, Edgar

140

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

141

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

142

Annual Report Alfvn Laboratory  

E-print Network

Annual Report 2001 Alfvén Laboratory Alfvén Laboratory Royal Institute of Technology SE 100 44 2001 Alfvén Laboratory Royal Institute of Technology CONTENTS Section page 1 HIGHLIGHTS 1 2 THE ALFV?N LABORATORY 3 2.1 Plasma Physics 5 2.2 Fusion Plasma Physics 6 2.3 Applied Electrophysics 7 2.3.1 Accelerator

Haviland, David

143

VACUUM LASER ACCELERATION EXPERIMENT PERSPECTIVE AT BROOKHAVEN NATIONAL LAB-ACCELERATOR TEST FACILITY  

E-print Network

VACUUM LASER ACCELERATION EXPERIMENT PERSPECTIVE AT BROOKHAVEN NATIONAL LAB-ACCELERATOR TEST This first stage experiment is a Proof-of-Principle to support our novel vacuum laser acceleration (VLA at the Brookhaven National Laboratory Accelerator Test Facility (ATF), an electron beam with initial energy of 15 Me

Brookhaven National Laboratory

144

Report on accelerated corrosion studies  

Microsoft Academic Search

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 electrical components exposed to environmental conditions representative of homes constructed with problem drywall. The conditions of the accelerated testing were chosen to produce corrosion product growth that

Curtis Dale Mowry; Sarah Jill Glass; Neil Robert Sorensen

2011-01-01

145

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

146

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

147

Accelerated Learning (?)  

Microsoft Academic Search

We wish to pose accelerated learning as a challenge for intelligent systems technology. Research on intelligent tutoring systems has proved that accelerated learning is possible. The Sherlock tutor for electronics troubleshooting, for example, condensed four years of on-the-job training to approximately 25 hours, compressing the duration of the experience-feedback-learning cycle. But accelerated learning should refer to more than the hastening

Robert R. Hoffman; Paul J. Feltovich; Stephen M. Fiore; Gary Klein; David Ziebell

2009-01-01

148

An Independent Freshman Laboratory.  

ERIC Educational Resources Information Center

Describes a first-year laboratory course designed to fulfill laboratory objectives of reinforcing lecture material, teaching experimental methodology, developing hands-on skills, and imparting a sense of error. The course's six segments examine: digital electronics with students building a photogate timer; error analysis; linear accelerated

Spencer, C. D.; Seligmann, P. F.

1992-01-01

149

s Accelerator Department Annual Progress Report  

E-print Network

& s Accelerator Department Annual Progress Report 1 January - 31 December 1986 Risø National Laboratory, DK-4000 Roskilde, Denmark February 1987 #12;RIS?-M-2633 ACCELERATOR DEPARTMENT Annual Progress AND MAINTENANCE OF THE IRRADIATION FACILITIES 23 3.1 HRC electron linear accelerator 23 3.2 Febetron, field

150

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 Mendona; P K Shukla

2004-01-01

151

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

152

Accelerated Reader.  

ERIC Educational Resources Information Center

This paper provides an overview of Accelerated Reader, a system of computerized testing and record-keeping that supplements the regular classroom reading program. Accelerated Reader's primary goal is to increase literature-based reading practice. The program offers a computer-aided reading comprehension and management program intended to motivate

Education Commission of the States, Denver, CO.

153

Ecloud Build-Up Simulations for the FNAL MI for a Mixed Fill Pattern: Dependence on Peak SEY and Pulse Intensity During the Ramp  

SciTech Connect

We present simulation results of the build-up of the electron-cloud density n{sub e} in three regions of the FNAL Main Injector (MI) for a beam fill pattern made up of 5 double booster batches followed by a 6th single batch. We vary the pulse intensity in the range N{sub t} = (2-5) x 10{sup 13}, and the beam kinetic energy in the range E{sub k} = 8-120 GeV. We assume a secondary electron emission model qualitatively corresponding to TiN, except that we let the peak value of the secondary electron yield (SEY) {delta}{sub max} vary as a free parameter in a fairly broad range. Our main conclusions are: (1) At fixed N{sub t} there is a clear threshold behavior of n{sub e} as a function of {delta}{sub max} in the range {approx} 1.1-1.3. (2) At fixed {delta}{sub max}, there is a threshold behavior of n{sub e} as a function of N{sub t} provided {delta}{sub max} is sufficiently high; the threshold value of N{sub t} is a function of the characteristics of the region being simulated. (3) The dependence on E{sub k} is weak except possibly at transition energy. Most of these results were informally presented to the relevant MI personnel in April 2010.

Furman, M. A.

2010-12-11

154

Annual Report Alfvn Laboratory  

E-print Network

of Technology CONTENTS Section page 1 HIGHLIGHTS 1 2 THE ALFV?N LABORATORY 5 2.1 Plasma Physics 7 2.2 Fusion Plasma Physics 10 2.3 Applied Electrophysics 15 2.3.1 Accelerator Technology 15 2.3.2 IndustrialAnnual Report 2004 Alfvén Laboratory Alfvén Laboratory RoyalInstitute ofTechnology SE 100 44

Haviland, David

155

Accelerated Degradation of Polymers  

NSDL National Science Digital Library

For this laboratory exercise, you will monitor changes in the visual appearance of the samples, chemical changes and molecular weight changes as a function of exposure condition. Analysis of the neat and degraded systems will be done using visual evaluation, FTIR analysis and GPC analysis. After in-class presentation, completion of hands-on laboratory experiment and review of the information provided, you should be able to: Confidently discuss the mechanism of breakdown for a polymeric material exposed to various environmental conditions. Prepare samples and record an accurate account of their preparation for use in an outdoor environment and in an accelerated weathering chamber (Q-sun).

Derosa, Rebecca L.

2008-09-26

156

LINAC for ADS application - accelerator technologies  

SciTech Connect

Sifnificant high-current, high-intensity accelerator research and development have been done in the recent past in the US, centered primarily at Los Alamos National Laboratory. These efforts have included designs for the Accelerator Production of Tritium Project, Accelerator Transmutation of Waste, and Accelerator Driven Systems, as well as many others. This past work and some specific design principles that were developed to optimie linac designs for ADS and other high-intensity applications will be discussed briefly.

Garnett, Robert W [Los Alamos National Laboratory; Sheffreld, Richard L [Los Alamos National Laboratory

2009-01-01

157

Wakefield accelerators  

SciTech Connect

The search for new methods to accelerate particle beams to high energy using high gradients has resulted in a number of candidate schemes. One of these, wakefield acceleration, has been the subject of considerable R D in recent years. This effort has resulted in successful proof of principle experiments and in increased understanding of many of the practical aspects of the technique. Some wakefield basics plus the status of existing and proposed experimental work is discussed, along with speculations on the future of wake field acceleration. 10 refs., 6 figs.

Simpson, J.D.

1990-01-01

158

Acceleration switch  

DOEpatents

The disclosure relates to an improved integrating acceleration switch of the type having a mass suspended within a fluid filled chamber, with the motion of the mass initially opposed by a spring and subsequently not so opposed.

Abbin, Jr., Joseph P. (Albuquerque, NM); Devaney, Howard F. (Cedar Crest, NM); Hake, Lewis W. (Albuquerque, NM)

1982-08-17

159

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

160

ACCELERATOR TUBES H. R. McK. HYDER  

E-print Network

ACCELERATOR TUBES H. R. McK. HYDER Nuclear Physics Laboratory, University of Oxford, Oxford OX1 3RH The characteristics and performance of accelerator tubes required by the new generation of large tandem accelerators conclusions are drawn about future progress and developments. ACCELERATOR TUBES AND INSULATORS. 1

Paris-Sud XI, Université de

161

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 (RRL) -- of Columbia University, and its operation is supported as a National Facility by the US Department of Energy (DOE). Fifteen different experiments were run during these 12 months, approximately the same as the previous two years. Brief summaries of each experiment are included. Accelerator usage is summarized and development activities are discussed. 7 refs., 4 tabs.

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

1990-07-01

162

Stan Brodsky SLAC National Accelerator Laboratory  

E-print Network

20 GeV/c Electrons on protons in a Hydrogen Target Discovery of the Quark Structure of Matter Friedman, Kendall, Taylor: Nobel Prize ep eX Discovery of quarks! #12;Deep inelastic electron-proton scattering · Rutherford scattering using very high-energy electrons striking protons Discovery of quarks

Wechsler, Risa H.

163

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

164

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

165

Powerline Conductor Accelerated Testing Facility (PCAT) The Powerline Conductor Accelerated Testing facility (PCAT) at Oak Ridge National  

E-print Network

Accelerated Testing facility (PCAT) at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee environmental conditions. The tests provide both the manufacturer and utilities with conductor performance dataPowerline Conductor Accelerated Testing Facility (PCAT) Overview: The Powerline Conductor

166

Analytical Performance of Accelerator Mass Spectrometry and Liquid Scintillation Counting for  

E-print Network

Analytical Performance of Accelerator Mass Spectrometry and Liquid Scintillation Counting for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California of California, San Francisco, California 94143 Accelerator mass spectrometry (AMS) has been applied

Hammock, Bruce D.

167

Compact accelerator  

DOEpatents

A compact linear accelerator having at least one strip-shaped Blumlein module which guides a propagating wavefront between first and second ends and controls the output pulse at the second end. Each Blumlein module has first, second, and third planar conductor strips, with a first dielectric strip between the first and second conductor strips, and a second dielectric strip between the second and third conductor strips. Additionally, the compact linear accelerator includes a high voltage power supply connected to charge the second conductor strip to a high potential, and a switch for switching the high potential in the second conductor strip to at least one of the first and third conductor strips so as to initiate a propagating reverse polarity wavefront(s) in the corresponding dielectric strip(s).

Caporaso, George J. (Livermore, CA); Sampayan, Stephen E. (Manteca, CA); Kirbie, Hugh C. (Los Alamos, NM)

2007-02-06

168

BICEP's acceleration  

NASA Astrophysics Data System (ADS)

The recent Bicep2 [1] detection of, what is claimed to be primordial B-modes, opens up the possibility of constraining not only the energy scale of inflation but also the detailed acceleration history that occurred during inflation. In turn this can be used to determine the shape of the inflaton potential V(phi) for the first time if a single, scalar inflaton is assumed to be driving the acceleration. We carry out a Monte Carlo exploration of inflationary trajectories given the current data. Using this method we obtain a posterior distribution of possible acceleration profiles epsilon(N) as a function of e-fold N and derived posterior distributions of the primordial power spectrum P(k) and potential V(phi). We find that the Bicep2 result, in combination with Planck measurements of total intensity Cosmic Microwave Background (CMB) anisotropies, induces a significant feature in the scalar primordial spectrum at scales k~ 10-3 Mpc -1. This is in agreement with a previous detection of a suppression in the scalar power [2].

Contaldi, Carlo R.

2014-10-01

169

BICEP's acceleration  

E-print Network

The recent BICEP2 detection of, what is claimed to be primordial $B$-modes, opens up the possibility of constraining not only the energy scale of inflation but also the detailed acceleration history that occurred during inflation. In turn this can be used to determine the shape of the inflaton potential $V(\\phi)$ for the first time - if a single, scalar inflaton is assumed to be driving the acceleration. We carry out a Monte Carlo exploration of inflationary trajectories given the current data. Using this method we obtain a posterior distribution of possible acceleration profiles $\\epsilon(N)$ as a function of $e$-fold $N$ and derived posterior distributions of the primordial power spectrum $P(k)$ and potential $V(\\phi)$. We find that the BICEP2 result, in combination with Planck measurements of total intensity Cosmic Microwave Background (CMB) anisotropies, induces a significant feature in the scalar primordial spectrum at scales $k\\sim 10^{-3}$ Mpc$^{-1}$. This is in agreement with a previous detection of a suppression in the scalar power.

Carlo R. Contaldi

2014-07-24

170

BICEP's acceleration  

E-print Network

The recent BICEP2 detection of, what is claimed to be primordial $B$-modes, opens up the possibility of constraining not only the energy scale of inflation but also the detailed acceleration history that occurred during inflation. In turn this can be used to determine the shape of the inflaton potential $V(\\phi)$ for the first time - if a single, scalar inflaton is assumed to be driving the acceleration. We carry out a Monte Carlo exploration of inflationary trajectories given the current data. Using this method we obtain a posterior distribution of possible acceleration profiles $\\epsilon(N)$ as a function of $e$-fold $N$ and derived posterior distributions of the primordial power spectrum $P(k)$ and potential $V(\\phi)$. We find that the BICEP2 result, in combination with Planck measurements of total intensity Cosmic Microwave Background (CMB) anisotropies, induces a significant feature in the scalar primordial spectrum at scales $k\\sim 10^{-3}$ Mpc$^{-1}$. This is in agreement with a previous detection of a...

Contaldi, Carlo R

2014-01-01

171

Advanced concepts for acceleration  

SciTech Connect

Selected examples of advanced accelerator concepts are reviewed. Such plasma accelerators as plasma beat wave accelerator, plasma wake field accelerator, and plasma grating accelerator are discussed particularly as examples of concepts for accelerating relativistic electrons or positrons. Also covered are the pulsed electron-beam, pulsed laser accelerator, inverse Cherenkov accelerator, inverse free-electron laser, switched radial-line accelerators, and two-beam accelerator. Advanced concepts for ion acceleration discussed include the electron ring accelerator, excitation of waves on intense electron beams, and two-wave combinations. (LEW)

Keefe, D.

1986-07-01

172

Non-accelerator Particle Physics  

E-print Network

Non-accelerator Particle Physics and Neutrino Physics Research programs of: Prof. Martin that often connect particle physics with astrophysics and cosmology Some questions: - What particles of the neutrino? #12;The techniques: Laboratory experiments, in the style of particle physics · High energy

Wechsler, Risa H.

173

Electron Accelerators for Environmental Protection  

NASA Astrophysics Data System (ADS)

This article gives an overview of existing and possible electron accelerator applications for environmental pollution control. Laboratory and pilot plant tests and industrial applications have illustrated the possibility of applying this technology for purification and treatment of gaseous, liquid, and solid wastes. Examples of ionizing radiation application to protect the environment and human health are discussed.

Chmielewski, Andrzej G.

2011-02-01

174

National Superconducting Cyclotron Laboratory  

E-print Network

capable accelerator facilities, the next generation of nuclear scientists will have at their dispos- al security, energy, materials science and quantum information processing. In short, the future of nuclear· laboratory in the United States Training ground for 10% of all U.S. nuclear science· doctoral students

175

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

176

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

177

Impact accelerations  

NASA Technical Reports Server (NTRS)

The degree to which impact acceleration is an important factor in space flight environments depends primarily upon the technology of capsule landing deceleration and the weight permissible for the associated hardware: parachutes or deceleration rockets, inflatable air bags, or other impact attenuation systems. The problem most specific to space medicine is the potential change of impact tolerance due to reduced bone mass and muscle strength caused by prolonged weightlessness and physical inactivity. Impact hazards, tolerance limits, and human impact tolerance related to space missions are described.

Vongierke, H. E.; Brinkley, J. W.

1975-01-01

178

Ring accelerators  

SciTech Connect

We present two-dimensional simulations in (r-z) and r-theta) cylinderical geometries of imploding-liner-driven accelerators of rings of charged particles. We address issues of azimuthal and longitudinal stability of the rings. We discuss self-trapping designs in which beam injection and extraction is aided by means of external cusp fields. Our simulations are done with the 2-1/2-D particle-in-cell plasma simulation code CLINER, which combines collisionless, electromagnetic PIC capabilities with a quasi-MHD finite element package.

Gisler, G.; Faehl, R.

1983-01-01

179

TRACKING ACCELERATOR SETTINGS.  

SciTech Connect

Recording setting changes within an accelerator facility provides information that can be used to answer questions about when, why, and how changes were made to some accelerator system. This can be very useful during normal operations, but can also aid with security concerns and in detecting unusual software behavior. The Set History System (SHS) is a new client-server system developed at the Collider-Accelerator Department of Brookhaven National Laboratory to provide these capabilities. The SHS has been operational for over two years and currently stores about IOOK settings per day into a commercial database management system. The SHS system consists of a server written in Java, client tools written in both Java and C++, and a web interface for querying the database of setting changes. The design of the SHS focuses on performance, portability, and a minimal impact on database resources. In this paper, we present an overview of the system design along with benchmark results showing the performance and reliability of the SHS over the last year.

D OTTAVIO,T.; FU, W.; OTTAVIO, D.P.

2007-10-15

180

The IAE Peking HI-13 tandem accelerator  

NASA Astrophysics Data System (ADS)

A new tandem accelerator laboratory is under construction at the Institute of Atomic Energy in Peking. This institute was built in 1958 and equipped with a reactor, cyclotron, electrostatic accelerator and some other facilities to meet the increasing interest in nuclear study and its application in China. The project of this tandem laboratory was approved in 1978. A 13 MV tandem accelerator will be provided by the High Voltage Engineering Corporation of Burlington, Massachusetts, USA, and a Q3D magnetic spectrometer by AB Scanditronix, Sweden. Some auxiliary systems, experimental equipment and the tank of the tandem are being designed and manufactured in China.

Ju-xian, Yu

1981-05-01

181

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

182

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

183

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

184

Advanced Visualization Technology for Terascale Particle Accelerator Simulations  

E-print Network

Advanced Visualization Technology for Terascale Particle Accelerator Simulations Kwan-Liu Ma £ Greg Accelerator Center Lawrence Berkeley National Laboratory Abstract This paper presents two new hardware modeling of next- generation accelerator designs. The first technique, based on a hybrid rendering approach

Ma, Kwan-Liu

185

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

186

2011 Dielectric Laser Acceleration Workshop (DLA2011)  

SciTech Connect

The first ICFA Mini-workshop on Dielectric Laser Accelerators was held on September 15-16, 2011 at SLAC National Accelerator Laboratory. We present the results of the Workshop, and discuss the main conclusions of the Accelerator Applications, Photonics, and Laser Technologies working groups. Over 50 participants from 4 countries participated, discussing the state of the art in photonic structures, laser science, and nanofabrication as it pertains to laser-driven particle acceleration in dielectric structures. Applications of this new and promising acceleration concept to discovery science and industrial, medical, and basic energy sciences were explored. The DLA community is presently focused on making demonstrations of high gradient acceleration and a compatible attosecond injector source - two critical steps towards realizing the potential of this technology.

Bermel, Peter; /MIT; Byer, Robert L.; /Stanford U., Phys. Dept.; Colby, Eric R.; /SLAC; Cowan, Benjamin M.; /Tech-X, Boulder; Dawson, Jay; /LLNL, Livermore; England, R.Joel; /SLAC; Noble, Robert J.; /SLAC; Qi, Ming-Hao; /Purdue U.; Yoder, Rodney B.; /Manhattanville Coll., Purchase

2012-04-17

187

The Radiological Research Accelerator Facility  

SciTech Connect

The Radiological Research Accelerator Facility (RARAF) is based on 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 (RRL) -- 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. Brief summaries of research experiments are included. Accelerator usage is summarized and development activities are discussed. 8 refs., 8 tabs.

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

1991-05-01

188

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

189

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 Alfvn 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

190

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

191

Chemical Accelerators The phrase "chemical accelerators"  

E-print Network

Meetings Chemical Accelerators The phrase "chemical accelerators" is scarcely older than for one or two dozen people grew to include nearly a hundred. Chemical accelerators is a name sug- gested by one of us for devices that produce beams of chemically interesting species at relative kinetic

Zare, Richard N.

192

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

193

NDCX-II, A New Induction Linear Accelerator for Warm Dense Matter Research  

Microsoft Academic Search

The Heavy Ion Fusion Science Virtual National Laboratory (HIFS-VNL), a collaboration between Lawrence Berkeley National Laboratory (LBNL), Lawrence Livermore National Laboratory (LLNL), and Princeton Plasma Physics Laboratory (PPPL), is currently constructing a new induction linear accelerator, called Neutralized Drift Compression eXperiment NDCX-II. The accelerator design makes effective use of existing components from LLNL's decommissioned Advanced Test Accelerator (ATA), especially induction

M. Leitner; F. Bieniosek; J. Kwan; G. Logan; W. Waldron; J. J. Barnard; A. Friedman; B. Sharp; E. Gilson; R. Davidson

2009-01-01

194

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

195

ISIS upgrades David Findlay  

E-print Network

ISIS upgrades David Findlay Head, Accelerator Division ISIS Department Rutherford Appleton Laboratory / STFC Proton Accelerators for Science and Innovation, 12­14 January 2012, FNAL #12;2 ISIS World for research in the physical and life sciences National and international community of >2000 scientists -- ISIS

McDonald, Kirk

196

Wakefield Acceleration in Structures  

Microsoft Academic Search

Wakefield acceleration in dielectric loaded structures is discussed in this paper. We present a description of the dielectric wakefield accelerator concept, comparing some features of the collinear and the two beam accelerator configurations. The Argonne Wakefield Accelerator Facility (AWA) is discussed in detail, including major upgrades that are presently taking place. The basic features and capabilities of the facility are

M. E. Conde

2002-01-01

197

The Spallation Neutron Source accelerator system design  

NASA Astrophysics Data System (ADS)

The Spallation Neutron Source (SNS) was designed and constructed by a collaboration of six U.S. Department of Energy national laboratories. The SNS accelerator system consists of a 1 GeV linear accelerator and an accumulator ring providing 1.4 MW of proton beam power in microsecond-long beam pulses to a liquid mercury target for neutron production. The accelerator complex consists of a front-end negative hydrogen-ion injector system, an 87 MeV drift tube linear accelerator, a 186 MeV side-coupled linear accelerator, a 1 GeV superconducting linear accelerator, a 248-m circumference accumulator ring and associated beam transport lines. The accelerator complex is supported by ~100 high-power RF power systems, a 2 K cryogenic plant, ~400 DC and pulsed power supply systems, ~400 beam diagnostic devices and a distributed control system handling ~100,000 I/O signals. The beam dynamics design of the SNS accelerator is presented, as is the engineering design of the major accelerator subsystems.

Henderson, S.; Abraham, W.; Aleksandrov, A.; Allen, C.; Alonso, J.; Anderson, D.; Arenius, D.; Arthur, T.; Assadi, S.; Ayers, J.; Bach, P.; Badea, V.; Battle, R.; Beebe-Wang, J.; Bergmann, B.; Bernardin, J.; Bhatia, T.; Billen, J.; Birke, T.; Bjorklund, E.; Blaskiewicz, M.; Blind, B.; Blokland, W.; Bookwalter, V.; Borovina, D.; Bowling, S.; Bradley, J.; Brantley, C.; Brennan, J.; Brodowski, J.; Brown, S.; Brown, R.; Bruce, D.; Bultman, N.; Cameron, P.; Campisi, I.; Casagrande, F.; Catalan-Lasheras, N.; Champion, M.; Champion, M.; Chen, Z.; Cheng, D.; Cho, Y.; Christensen, K.; Chu, C.; Cleaves, J.; Connolly, R.; Cote, T.; Cousineau, S.; Crandall, K.; Creel, J.; Crofford, M.; Cull, P.; Cutler, R.; Dabney, R.; Dalesio, L.; Daly, E.; Damm, R.; Danilov, V.; Davino, D.; Davis, K.; Dawson, C.; Day, L.; Deibele, C.; Delayen, J.; DeLong, J.; Demello, A.; DeVan, W.; Digennaro, R.; Dixon, K.; Dodson, G.; Doleans, M.; Doolittle, L.; Doss, J.; Drury, M.; Elliot, T.; Ellis, S.; Error, J.; Fazekas, J.; Fedotov, A.; Feng, P.; Fischer, J.; Fox, W.; Fuja, R.; Funk, W.; Galambos, J.; Ganni, V.; Garnett, R.; Geng, X.; Gentzlinger, R.; Giannella, M.; Gibson, P.; Gillis, R.; Gioia, J.; Gordon, J.; Gough, R.; Greer, J.; Gregory, W.; Gribble, R.; Grice, W.; Gurd, D.; Gurd, P.; Guthrie, A.; Hahn, H.; Hardek, T.; Hardekopf, R.; Harrison, J.; Hatfield, D.; He, P.; Hechler, M.; Heistermann, F.; Helus, S.; Hiatt, T.; Hicks, S.; Hill, J.; Hill, J.; Hoff, L.; Hoff, M.; Hogan, J.; Holding, M.; Holik, P.; Holmes, J.; Holtkamp, N.; Hovater, C.; Howell, M.; Hseuh, H.; Huhn, A.; Hunter, T.; Ilg, T.; Jackson, J.; Jain, A.; Jason, A.; Jeon, D.; Johnson, G.; Jones, A.; Joseph, S.; Justice, A.; Kang, Y.; Kasemir, K.; Keller, R.; Kersevan, R.; Kerstiens, D.; Kesselman, M.; Kim, S.; Kneisel, P.; Kravchuk, L.; Kuneli, T.; Kurennoy, S.; Kustom, R.; Kwon, S.; Ladd, P.; Lambiase, R.; Lee, Y. Y.; Leitner, M.; Leung, K.-N.; Lewis, S.; Liaw, C.; Lionberger, C.; Lo, C. C.; Long, C.; Ludewig, H.; Ludvig, J.; Luft, P.; Lynch, M.; Ma, H.; MacGill, R.; Macha, K.; Madre, B.; Mahler, G.; Mahoney, K.; Maines, J.; Mammosser, J.; Mann, T.; Marneris, I.; Marroquin, P.; Martineau, R.; Matsumoto, K.; McCarthy, M.; McChesney, C.; McGahern, W.; McGehee, P.; Meng, W.; Merz, B.; Meyer, R.; Meyer, R.; Miller, B.; Mitchell, R.; Mize, J.; Monroy, M.; Munro, J.; Murdoch, G.; Musson, J.; Nath, S.; Nelson, R.; Nelson, R.; O'Hara, J.; Olsen, D.; Oren, W.; Oshatz, D.; Owens, T.; Pai, C.; Papaphilippou, I.; Patterson, N.; Patterson, J.; Pearson, C.; Pelaia, T.; Pieck, M.; Piller, C.; Plawski, T.; Plum, M.; Pogge, J.; Power, J.; Powers, T.; Preble, J.; Prokop, M.; Pruyn, J.; Purcell, D.; Rank, J.; Raparia, D.; Ratti, A.; Reass, W.; Reece, K.; Rees, D.; Regan, A.; Regis, M.; Reijonen, J.; Rej, D.; Richards, D.; Richied, D.; Rode, C.; Rodriguez, W.; Rodriguez, M.; Rohlev, A.; Rose, C.; Roseberry, T.; Rowton, L.; Roybal, W.; Rust, K.; Salazer, G.; Sandberg, J.; Saunders, J.; Schenkel, T.; Schneider, W.; Schrage, D.; Schubert, J.; Severino, F.; Shafer, R.; Shea, T.; Shishlo, A.; Shoaee, H.; Sibley, C.; Sims, J.; Smee, S.; Smith, J.; Smith, K.; Spitz, R.; Staples, J.; Stein, P.; Stettler, M.; Stirbet, M.; Stockli, M.; Stone, W.; Stout, D.; Stovall, J.; Strelo, W.; Strong, H.; Sundelin, R.; Syversrud, D.; Szajbler, M.; Takeda, H.; Tallerico, P.; Tang, J.; Tanke, E.; Tepikian, S.; Thomae, R.; Thompson, D.; Thomson, D.; Thuot, M.; Treml, C.; Tsoupas, N.; Tuozzolo, J.; Tuzel, W.; Vassioutchenko, A.; Virostek, S.; Wallig, J.; Wanderer, P.; Wang, Y.; Wang, J. G.; Wangler, T.; Warren, D.; Wei, J.; Weiss, D.; Welton, R.; Weng, J.; Weng, W.-T.; Wezensky, M.; White, M.; Whitlatch, T.; Williams, D.; Williams, E.; Wilson, K.; Wiseman, M.; Wood, R.; Wright, P.; Wu, A.; Ybarrolaza, N.; Young, K.; Young, L.; Yourd, R.; Zachoszcz, A.; Zaltsman, A.; Zhang, S.; Zhang, W.; Zhang, Y.; Zhukov, A.

2014-11-01

198

Wakefield acceleration in structures.  

SciTech Connect

Wakefield acceleration in dielectric loaded structures is discussed in this paper. We present a description of the dielectric wakefield accelerator concept, comparing some features of the collinear and the two beam accelerator configurations. The Argonne Wakefield Accelerator Facility (AWA) is discussed in detail, including major upgrades that are presently taking place. The basic features and capabilities of the facility are presented, and the dielectric wakefield acceleration results are briefly summarized. Possible variants of the two beam accelerator configuration are discussed, and work on planar dielectric structures in various institutions is presented. We conclude this report mentioning prospective achievements of dielectric wakefield accelerating structures.

Conde, M. E.

2002-09-17

199

Wakefield Acceleration in Structures  

NASA Astrophysics Data System (ADS)

Wakefield acceleration in dielectric loaded structures is discussed in this paper. We present a description of the dielectric wakefield accelerator concept, comparing some features of the collinear and the two beam accelerator configurations. The Argonne Wakefield Accelerator Facility (AWA) is discussed in detail, including major upgrades that are presently taking place. The basic features and capabilities of the facility are presented, and the dielectric wakefield acceleration results are briefly summarized. Possible variants of the two beam accelerator configuration are discussed, and work on planar dielectric structures in various institutions is presented. We conclude this report mentioning prospective achievements of dielectric wakefield accelerating structures.

Conde, M. E.

2002-01-01

200

Wakefield Acceleration in Structures  

NASA Astrophysics Data System (ADS)

Wakefield acceleration in dielectric loaded structures is discussed in this paper. We present a description of the dielectric wakefield accelerator concept, comparing some features of the collinear and the two beam accelerator configurations. The Argonne Wakefield Accelerator Facility (AWA) is discussed in detail, including major upgrades that are presently taking place. The basic features and capabilities of the facility are presented, and the dielectric wakefield acceleration results are briefly summarized. Possible variants of the two beam accelerator configuration are discussed, and work on planar dielectric structures in various institutions is presented. We conclude this report mentioning prospective achievements of dielectric wakefield accelerating structures.

Conde, Manoel E.

2002-12-01

201

Non-Dispersive, Accelerated Matter-Waves  

E-print Network

It is shown that under certain dynamical conditions a material wave packet displays coherent, non-dispersive accelerated evolution in gravitational field over a modulated atomic mirror. The phenomenon takes place as a consequence of simultaneous presence of the dynamical localization and the coherent Fermi acceleration for the same modulation amplitude. It is purely a quantum mechanical effect as the windows of modulation strengths supporting dynamical localization and Fermi acceleration overlap for larger effective Plank constant. Present day experimental techniques make it feasible to realize the system in laboratory.

Farhan Saif; Khalid Naseer; Muhammad Ayub

2014-06-22

202

Faraday Acceleration with Radio-frequency Assisted Discharge (FARAD) Edgar Y. Choueiri  

E-print Network

. Polzin Electric Propulsion and Plasma Dynamics Laboratory (EPPDyL) Mechanical and Aerospace Engineering, and electromagnetic acceleration using an inductive coil is presented. The advantages of this concept include efficient plasma production, magnetic field guided mass injection, and electromagnetic acceleration

Choueiri, Edgar

203

PROPOSAL FOR AN EXPERIMENT PROGRAM IN NEUTRINO PHYSICS AND PROTON DECAY IN THE HOMESTAKE LABORATORY.  

SciTech Connect

This report is intended to describe first, the principal physics reasons for an ambitious experimental program in neutrino physics and proton decay based on construction of a series of massive water Cherenkov detectors located deep underground (4850 ft) in the Homestake Mine of the South Dakota Science and Technology Authority (SDSTA); and second, the engineering design of the underground chambers to house the Cherenkov detector modules; and third, the conceptual design of the water Cherenkov detectors themselves for this purpose. In this proposal we show the event rates and physics sensitivity for beams from both FNAL (1300 km distant from Homestake) and BNL (2540 km distant from Homestake). The program we propose will benefit with a beam from FNAL because of the high intensities currently available from the Main Injector with modest upgrades. The possibility of tuning the primary proton energy over a large range from 30 to 120 GeV also adds considerable flexibility to the program from FNAL. On the other hand the beam from BNL over the larger distance will produce very large matter effects, and consequently a hint of new physics (beyond CP violation) can be better tested with that configuration. In this proposal we focus on the CP violation physics. Included in this document are preliminary costs and time-to-completion estimates which have been exposed to acknowledged experts in their respective areas. This presentation is not, however, to be taken as a technical design report with the extensive documentation and contingency costs that a TDR usually entails. Nevertheless, some contingency factors have been included in the estimates given here. The essential ideas expressed here were first laid out in a letter of intent to the interim director of the Homestake Laboratory on July 26, 2001. Since that time, the prospect of a laboratory in the Homestake Mine has been realized, and the design of a long baseline neutrino experiment has been refined. The extrapolation contained in this proposal is within the common domain of thinking in the area of physics discussed here. It needs now only the encouragement of the funding agencies, NSF and DOE.

DIWAN, M.; KETTELL, S.; LITTENBERG, W.; MARIANO, W.; PARSA, Z.; SAMIOS, N.; WHITE, S.; ET AL.

2006-07-24

204

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

205

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

206

TURBULENT SHEAR ACCELERATION  

SciTech Connect

We consider particle acceleration by large-scale incompressible turbulence with a length scale larger than the particle mean free path. We derive an ensemble-averaged transport equation of energetic charged particles from an extended transport equation that contains the shear acceleration. The ensemble-averaged transport equation describes particle acceleration by incompressible turbulence (turbulent shear acceleration). We find that for Kolmogorov turbulence, the turbulent shear acceleration becomes important on small scales. Moreover, using Monte Carlo simulations, we confirm that the ensemble-averaged transport equation describes the turbulent shear acceleration.

Ohira, Yutaka, E-mail: ohira@phys.aoyama.ac.jp [Department of Physics and Mathematics, Aoyama Gakuin University, 5-10-1 Fuchinobe, Sagamihara 252-5258 (Japan)

2013-04-10

207

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

208

Advanced modeling of high intensity accelerators  

SciTech Connect

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goals of this project were three-fold: (1) to develop a new capability, based on high performance (parallel) computers, to perform large scale simulations of high intensity accelerators; (2) to apply this capability to modeling high intensity accelerators under design at LANL; and (3) to use this new capability to improve the understanding of the physics of intense charge particle beams, especially in regard to the issue of beam halo formation. All of these goals were met. In particular, the authors introduced split-operator methods as a powerful and efficient means to simulate intense beams in the presence of rapidly varying accelerating and focusing fields. They then applied these methods to develop scaleable, parallel beam dynamics codes for modeling intense beams in linacs, and in the process they implemented a new three-dimensional space charge algorithm. They also used the codes to study a number of beam dynamics issues related to the Accelerator Production of Tritium (APT) project, and in the process performed the largest simulations to date for any accelerator design project. Finally, they used the new modeling capability to provide direction and validation to beam physics studies, helping to identify beam mismatch as a major source of halo formation in high intensity accelerators. This LDRD project ultimately benefited not only LANL but also the US accelerator community since, by promoting expertise in high performance computing and advancing the state-of-the-art in accelerator simulation, its accomplishments helped lead to approval of a new DOE Grand Challenge in Computational Accelerator Physics.

Ryne, R.D.; Habib, S.; Wangler, T.P.

1998-11-01

209

Linear Accelerator (LINAC)  

MedlinePLUS

... position doesn't vary from the original plan. Safety of the staff operating the linear accelerator is also important. The linear accelerator sits in a room with lead and concrete walls so that the ...

210

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

211

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

212

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

213

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

214

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.

215

Acceleration: It's Elementary  

ERIC Educational Resources Information Center

Acceleration is one tool for providing high-ability students the opportunity to learn something new every day. Some people talk about acceleration as taking a student out of step. In actuality, what one is doing is putting a student in step with the right curriculum. Whole-grade acceleration, also called grade-skipping, usually happens between

Willis, Mariam

2012-01-01

216

KEKB accelerator control system  

Microsoft Academic Search

The KEKB accelerator control system including a control computer system, a timing distribution system, and a safety control system are described. KEKB accelerators were installed in the same tunnel where the TRISTAN accelerator was. There were some constraints due to the reused equipment. The control system is based on Experimental Physics and Industrial Control System (EPICS). In order to reduce

Nobumasa Akasaka; Atsuyoshi Akiyama; Sakae Araki; Kazuro Furukawa; Tadahiko Katoh; Takashi Kawamoto; Ichitaka Komada; Kikuo Kudo; Takashi Naito; Tatsuro Nakamura; Jun-Ichi Odagiri; Yukiyoshi Ohnishi; Masayuki Sato; Masaaki Suetake; Shigeru Takeda; Yasunori Takeuchi; Noboru Yamamoto; Masakazu Yoshioka; Eji Kikutani

2003-01-01

217

Accelerator experiments contradicting general relativity  

E-print Network

The deflection of gamma-rays in Earth's gravitational field is tested in laser Compton scattering at high energy accelerators. Within a formalism connecting the bending angle to the photon's momentum it follows that detected gamma-ray spectra are inconsistent with a deflection magnitude of 2.78 nrad, predicted by Einstein's gravity theory. Moreover, preliminary results for 13-28 GeV photons from two different laboratories show opposite - away from the Earth - deflection, amounting to 33.8-0.8 prad. I conclude that general relativity, which describes gravity at low energies precisely, break down at high energies.

Gharibyan, Vahagn

2014-01-01

218

Accelerator experiments contradicting general relativity  

E-print Network

The deflection of gamma-rays in Earth's gravitational field is tested in laser Compton scattering at high energy accelerators. Within a formalism connecting the bending angle to the photon's momentum it follows that detected gamma-ray spectra are inconsistent with a deflection magnitude of 2.78 nrad, predicted by Einstein's gravity theory. Moreover, preliminary results for 13-28 GeV photons from two different laboratories show opposite - away from the Earth - deflection, amounting to 33.8-0.8 prad. I conclude that general relativity, which describes gravity at low energies precisely, break down at high energies.

Vahagn Gharibyan

2014-01-13

219

Newton's Second Law: How does acceleration change with varying forces?  

NSDL National Science Digital Library

This activity is a laboratory experiment where students change the force applied to a lab cart to investigate the relationship between force, mass and acceleration. They create and analyze graphs to see if Newton's second law applies to the experiment.

220

Biological assessments for the low energy demonstration accelerator, 1996  

SciTech Connect

This report discusses the biological impact to the area around the Los Alamos National Laboratory of the Low Energy Demonstration Accelerator. In particular the impact to the soils, water quality, vegetation, and wildlife are discussed.

Cross, S.

1997-03-01

221

Radiation safety training for accelerator facilities  

SciTech Connect

In November 1992, a working group was formed within the U.S. Department of Energy`s (DOE`s) accelerator facilities to develop a generic safety training program to meet the basic requirements for individuals working in accelerator facilities. This training, by necessity, includes sections for inserting facility-specific information. The resulting course materials were issued by DOE as a handbook under its technical standards in 1996. Because experimenters may be at a facility for only a short time and often at odd times during the day, the working group felt that computer-based training would be useful. To that end, Lawrence Livermore National Laboratory (LLNL) and Argonne National Laboratory (ANL) together have developed a computer-based safety training program for accelerator facilities. This interactive course not only enables trainees to receive facility- specific information, but time the training to their schedule and tailor it to their level of expertise.

Trinoskey, P.A.

1997-02-01

222

Acceleration gradient of a plasma wakefield accelerator  

NASA Astrophysics Data System (ADS)

The phase velocity of the wakefield waves is identical to the electron beam velocity. A theoretical analysis indicates that the acceleration gradient of the wakefield accelerator normalized by the wave breaking amplitude is K0(?)/K1(?), where K0(?) and K1(?) are the modified Bessel functions of the second kind of order zero and one, respectively and ? is the beam parameter representing the beam intensity. It is also shown that the beam density must be considerably higher than the diffuse plasma density for the large radial velocity of plasma electrons that are required for a high acceleration gradient.

Uhm, Han S.

2008-02-01

223

New limits on Magnetic Monopoles searches from accelerator and non-accelerator experiments  

E-print Network

Here the status of the searches for ``classical Dirac'' Magnetic Monopoles (MMs) at accelerators and for GUT MMs in the cosmic radiation is discussed. We present recent analysis for ``classical Dirac'' monopoles at accelerators and the lowest flux upper limit for Magnetic Monopoles in the mass range 10$^{5}$ - 10$^{12}$ GeV obtained with the SLIM experiment at the Chacaltaya High Altitude Laboratory (5290 m a.s.l.).

M. Cozzi

2007-03-08

224

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

225

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

226

Laboratory 10 Control Systems Laboratory ECE3557 Laboratory 10  

E-print Network

Laboratory 10 Control Systems Laboratory ECE3557 Laboratory 10 State Feedback Controller.87 ? 10-7 kg-m2 , and Jl = 3 ? 10-5 kg-m2 . Page 1 of 7 #12;Laboratory 10 Control Systems Laboratory ECE;Laboratory 10 Control Systems Laboratory ECE3557 10.3 Laboratory Preparation 1. Write a MATLAB script

227

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

228

Measurements of current sheet canting in a pulsed electromagnetic accelerator  

E-print Network

the per- formance of pulsed electromagnetic accelerators in the con- text of plasma propulsion. PPTs haveMeasurements of current sheet canting in a pulsed electromagnetic accelerator T. E. Markusic, E. Y. Choueiri, and J. W. Berkery Electric Propulsion and Plasma Dynamics Laboratory (EPPDyL), Mechanical

Choueiri, Edgar

229

MUON ACCELERATION IN FFAG RINGS , Katharinenstr. 17, Berlin, Germany  

E-print Network

variation) that are essentially strong-focusing rings with a dispersion small enough to keep muons overMUON ACCELERATION IN FFAG RINGS E. Keil , Katharinenstr. 17, Berlin, Germany A.M. Sessler , Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA Abstract Compared to muon acceleration in re

Keil, Eberhard

230

Ion accelerator applications in medicine and cultural heritage  

Microsoft Academic Search

Formerly, accelerator laboratories were mainly dedicated to nuclear physics. Today, they are used in up-coming research fields and applications like material analysis and material science as well as biology, medicine or archaeology. Practical applications have been developed, involving hospitals, industry and even humanists in the use of accelerators. This paper focuses on some medical and analytical applications of the HMI

A. Denker; D. Cordini; J. Heufelder; H. Homeyer; H. Kluge; I. Simiantonakis; R. Stark; A. Weber

2007-01-01

231

A strategy for residual acceleration data reduction and dissemination  

Microsoft Academic Search

A data reduction plan is being developed to efficiently process residual acceleration data from orbiting space laboratories. Implementation of the reduction plan will result in a useful, manageable accelerometer data base which can be readily employed by principal investigators during post-flight analysis of experimental results. The data reduction plan will also assist in the characterization of the acceleration environment of

Melissa J. B. Rogers; J. Iwan; D. Alexander

1991-01-01

232

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

233

Physics Classroom: The Acceleration of Gravity  

NSDL National Science Digital Library

This tutorial introduces the concept of gravitational acceleration. This tutorial explains the notation, numerical value, and how the numerical value of the gravitational acceleration is obtained. This tutorial includes two widgets: one where one can see the strength of the acceleration of gravity from any location on Earth, and another one where one can see a comparison of the acceleration of gravity of planets in our solar system to everyday objects, and to other objects in the solar system. The tutorial also includes a pictorial example, along with the widgets, along with links to tutorials to other general Physics concepts, simulations, and student activities. This is part of The Physics Classroom. This web site also includes interactive tools to help students with concepts and problem solving, worksheets for student assignments, and recommendations for simple introductory laboratories.

Henderson, Tom

2012-04-28

234

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

235

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

236

Virtual Accelerator for Accelerator Optics Improvement  

SciTech Connect

Through determination of all quadrupole strengths and sextupole feed-downs by fitting quantities derivable from precision orbit measurement, one can establish a virtual accelerator that matches the real accelerator optics. These quantities (the phase advances, the Green's functions, and the coupling ellipses tilt angles and axis ratios) are obtained by analyzing turn-by-turn Beam Position Monitor (BPM) data with a model-independent analysis (MIA). Instead of trying to identify magnet errors, a limited number of quadrupoles are chosen for optimized strength adjustment to improve the virtual accelerator optics and then applied to the real accelerator accordingly. These processes have been successfully applied to PEP-II rings for beta beating fixes, phase and working tune adjustments, and coupling reduction to improve PEP-II luminosity.

Yan, Y.T.; Cai, Y.; Decker, F-J.; Ecklund, S.; Irwin, J.; Seeman, J.; Sillivan, M.; Turner, J.; Wienands, U.; /SLAC

2005-09-30

237

High brightness electron accelerator  

SciTech Connect

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 electrons, where the solenoid is configured to provide a substantially uniform magnetic field over the photocathode surface to minimize emittance of the electrons as the electrons enter the first cavity.

Sheffield, R.L.; Carlsten, B.E.; Young, L.M.

1992-12-31

238

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

239

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

240

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

241

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

242

The CEBAF cryogenic system: Continuous Electron Beam Accelerator Facility  

SciTech Connect

The CEBAF superconducting linear accelerator incorporates cryogenic refrigeration equipment at three locations within the site: the Central Helium Liquefier, located in the center of the accelerator; the experimental end station refrigerator; and the test laboratory refrigerator located in the Cryogenic Test Facility (CTF) adjacent to the test laboratory. The CEBAF cryogenic system will provide 2K refrigeration to the linacs of the accelerator and test laboratory and 4.5K refrigeration for the end station experimental halls. The Central Helium Liquefier and the test laboratory systems will produce 45K supercritical gaseous helium for shield refrigeration. Liquid nitrogen shields will also be incorporated in the test laboratory and end stations. 6 refs., 5 figs.

Chronis, W.C.; Arenius, D.; Kashy, D.; Keesee, M.; Rode, C.H.

1989-01-01

243

Paleomagnetics Laboratory  

NSDL National Science Digital Library

At this website, the California Institute of Technology's Paleomagnetics Laboratory promotes its research of weakly magnetic geologic and biological materials. Users can learn about the facilities such as the biomagnetics lab and the automatic sampler. The website features the laboratory's recent research on many topics including extraterrestrial magnetism, magnetofossils, and historical geomagnetic field behavior. Visitors can find out more about the many laboratory members' research activities through links to their home pages. Researchers can download a selection of the group's publications. Everyone can enjoy the amazing images from recent geologic field trips across the globe.

244

Cryogenic Technology for Superconducting Accelerators  

NASA Astrophysics Data System (ADS)

Superconducting devices such as magnets and cavities are key components in the accelerator field for increasing the beam energy and intensity, and at the same time making the system compact and saving on power consumption in operation. An effective cryogenic system is required to cool and keep the superconducting devices in the superconducting state stably and economically. The helium refrigeration system for application to accelerators will be discussed in this review article. The concept of two cooling modes -- the liquefier and refrigerator modes -- will be discussed in detail because of its importance for realizing efficient cooling and stable operation of the system. As an example of the practical cryogenic system, the TRISTAN cryogenic system of KEK Laboratory will be treated in detail and the main components of the cryogenic system, including the high-performance multichannel transfer line and liquid nitrogen circulation system at 80K, will also be discussed. In addition, we will discuss the operation of the cryogenic system, including the quench control and safety of the system. The satellite refrigeration system will be discussed because of its potential for wide application in medium-size accelerators and in industry.

Hosoyama, Kenji

2012-01-01

245

Self-accelerating warped braneworlds  

SciTech Connect

Braneworld models with induced gravity have the potential to replace dark energy as the explanation for the current accelerating expansion of the Universe. The original model of Dvali, Gabadadze, and Porrati (DGP) demonstrated the existence of a 'self-accelerating' branch of background solutions, but suffered from the presence of ghosts. We present a new large class of braneworld models which generalize the DGP model. Our models have negative curvature in the bulk, allow a second brane, and have general brane tensions and localized curvature terms. We exhibit three different kinds of ghosts, associated to the graviton zero mode, the radion, and the longitudinal components of massive graviton modes. The latter two species occur in the DGP model, for negative and positive brane tension, respectively. In our models, we find that the two kinds of DGP ghosts are tightly correlated with each other, but are not always linked to the feature of self-acceleration. Our models are a promising laboratory for understanding the origins and physical meaning of braneworld ghosts, and perhaps for eliminating them altogether.

Carena, Marcela; Lykken, Joseph; Santiago, Jose [Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, Illinois 60510 (United States); Park, Minjoon [Department of Physics, University of California, Davis, California 95616 (United States)

2007-01-15

246

Self-accelerating Warped Braneworlds  

SciTech Connect

Braneworld models with induced gravity have the potential to replace dark energy as the explanation for the current accelerating expansion of the Universe. The original model of Dvali, Gabadadze and Porrati (DGP) demonstrated the existence of a ''self-accelerating'' branch of background solutions, but suffered from the presence of ghosts. We present a new large class of braneworld models which generalize the DGP model. Our models have negative curvature in the bulk, allow a second brane, and have general brane tensions and localized curvature terms. We exhibit three different kinds of ghosts, associated to the graviton zero mode, the radion, and the longitudinal components of massive graviton modes. The latter two species occur in the DGP model, for negative and positive brane tension respectively. In our models, we find that the two kinds of DGP ghosts are tightly correlated with each other, but are not always linked to the feature of self-acceleration. Our models are a promising laboratory for understanding the origins and physical meaning of braneworld ghosts, and perhaps for eliminating them altogether.

Carena, Marcela; Lykken, Joseph; /Fermilab; Park, Minjoon; /UC, Davis; Santiago, Jose; /Fermilab

2006-11-01

247

Uniformly accelerated black holes  

NASA Astrophysics Data System (ADS)

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

Letelier, Patricio S.; Oliveira, Samuel R.

2001-09-01

248

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

249

Space Acceleration Measurement System  

NASA Technical Reports Server (NTRS)

This training video, presented by the Lewis Research Center's Space Experiments Division, gives a background and detailed instructions for preparing the space acceleration measurement system (SAMS) for use. The SAMS measures, conditions, and records forces of low gravity accelerations, and is used to determine the effect of these forces on various experiments performed in microgravity. Inertial sensors are used to measure positive and negative acceleration over a specified frequency range. The video documents the SAMS' uses in different configurations during shuttle missions.

1993-01-01

250

G Accelerator Applications  

Microsoft Academic Search

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

Malcolm Ellis; Grahame Blair; Yagmur Torun; Tom Roberts

2006-01-01

251

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

252

FFAGS for rapid acceleration  

NASA Astrophysics Data System (ADS)

When large transverse and longitudinal emittances are to be transported through a circular machine, extremely rapid acceleration holds the advantage that the beam becomes immune to nonlinear resonances because there is insufficient time for amplitudes to build up. Uncooled muon beams exhibit large emittances and require fast acceleration to avoid decay losses and would benefit from this style of acceleration. The approach here employs a fixed-field alternating gradient or FFAG magnet structure and a fixed-frequency acceleration system. Acceptance is enhanced by the use only of linear lattice elements, and fixed-frequency rf enables the use of cavities with large shunt resistance and quality factor.

Johnstone, C.; Koscielniak, S.

2003-05-01

253

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

254

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,

255

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

256

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

257

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

258

Accelerator Technology Program. Status report, April-September 1985  

SciTech Connect

This report presents highlights of major projects in the Accelerator Technology (AT) Division of the Los Alamos National Laboratory. Radio-frequency and microwave technology are dealt with. The p-bar gravity experiment, accelerator theory and simulation activities, the Proton Storage Ring, and the Fusion Materials Irradiation Test accelerator are discussed. Activities on the proposed LAMPF II accelerator, the BEAR (Beam Experiment Aboard Rocket) project, beam dynamics, the National Bureau of Standards racetrack microtron, and the University of Illinois racetrack microtron are covered. Papers published by AT-Division personnel during this reporting period are listed.

Jameson, R.A.; Schriber, S.O. (comps.)

1986-09-01

259

Acceleration Measurements Using Smartphone Sensors: Dealing with the Equivalence Principle  

E-print Network

Acceleration sensors built into smartphones, i-pads or tablets can conveniently be used in the Physics laboratory. By virtue of the equivalence principle, a sensor fixed in a non-inertial reference frame cannot discern between a gravitational field and an accelerated system. Accordingly, acceleration values read by these sensors must be corrected for the gravitational component. A physical pendulum was studied by way of example, and absolute acceleration and rotation angle values were derived from the measurements made by the accelerometer and gyroscope. Results were corroborated by comparison with those obtained by video analysis. The limitations of different smartphone sensors are discussed.

Monteiro, Martn; Mart, Arturo C

2014-01-01

260

What can we expect from future accelerators  

SciTech Connect

This talk covers a general but highly subjective overview of the expectation for new accelerator development. An updated version of the Livingston chart demonstrates the exponential growth in time of the equivalent laboratory energy of accelerators. A similar Livingston chart pertaining only to electron-positron colliders shows an exponential growth but in the past only one technology - electron-positron storage rings - have been responsible for this development. The question addressed is whether the type of exponential growth reflected by these two charts can be sustained in the future.

Panofsky, W.K.H.

1984-06-01

261

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

262

Technology development for high power induction 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.

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

1985-06-11

263

Collider-Accelerator Department Overview Derek I. Lowenstein  

E-print Network

-NE) · Booster · NASA Space Radiation Laboratory (NASA, $5.5M/year, incl. $2M for Medical and Biology Departments Engineers/Professional 144 114 23 5 2 Designers/Technicians 196 155 32 6 3 Admin./Clerical 24 21 2 1 0 support ~13 FTEs are purchased as Laboratory assigned trades. #12;4 Collider Accelerator Department

264

Resource Letter AFHEP-1: Accelerators for the Future of High-Energy Physics  

NASA Astrophysics Data System (ADS)

This Resource Letter provides a guide to literature concerning the development of accelerators for the future of high-energy physics. Research articles, books, and Internet resources are cited for the following topics: motivation for future accelerators, present accelerators for high-energy physics, possible future machine, and laboratory and collaboration websites.

Barletta, William A.

2012-02-01

265

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

266

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

SciTech Connect

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

Siemann, R.H.; /SLAC

2011-10-24

267

The principle of phase stability and the accelerator program at Berkeley, 1945--1954  

SciTech Connect

The discovery of the Principle of Phase Stability by Vladimir Veksler and Edwin McMillian and the end of the war released a surge of accelerator activity at the Lawrence Berkeley Laboratory (then The University of California Radiation Laboratory). Six accelerators incorporating the Principle of Phase Stability were built in the period 1945--1954.

Lofgren, E.J.

1994-07-01

268

Laboratory 11 Control Systems Laboratory ECE3557 Laboratory 11  

E-print Network

Laboratory 11 Control Systems Laboratory ECE3557 Laboratory 11 State Feedback Controller of the combined system (i.e., servomotor and flexible joint) introduced in the Laboratory 8 (refer to [1 of the flexible joint: Page 1 of 7 #12;Laboratory 11 Control Systems Laboratory ECE3557 · : motor shaft position

269

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

270

Teaching and Research with Accelerators at Tarleton State University  

SciTech Connect

Tarleton State University students began performing both research and laboratory experiments using accelerators in 1998 through visitation programs at the University of North Texas, US Army Research Laboratory, and the Naval Surface Warfare Center at Carderock. In 2003, Tarleton outfitted its new science building with a 1 MV pelletron that was donated by the California Institution of Technology. The accelerator has been upgraded and supports a wide range of classes for both the Physics program and the ABET accredited Engineering Physics program as well as supplying undergraduate research opportunities on campus. A discussion of various laboratory activities and research projects performed by Tarleton students will be presented.

Marble, Daniel K. [Department of Engineering and Physisc, Box T-390, Tarleton State University, Stephenville, Texas, 76402 (United States)

2009-03-10

271

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

272

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

273

Piezoelectric angular acceleration sensor  

Microsoft Academic Search

This paper deals with a piezoelectric angular acceleration sensor, which might be proposed by us, first, as a new concept of the sensor to detect a rotational motion only. In the first part of this paper are dealt with some concrete constructions of this new concept of angular acceleration sensor, composed of piezoelectric transducers. The second part contains their basic

Y. Tomikawa; S. Okada

2003-01-01

274

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

275

Accelerators (4/5)  

SciTech Connect

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

2009-07-08

276

Accelerators (3/5)  

SciTech Connect

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

2009-07-07

277

Accelerators (5/5)  

SciTech Connect

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

2009-07-09

278

Neutrino physics at accelerators  

E-print Network

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

Enrique Fernandez

2006-07-16

279

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

280

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

281

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

282

Uniformly accelerated black holes  

Microsoft Academic Search

The static and stationary C metric are examined in a generic framework and their interpretations studied in some detail, especially those with two event horizons, one for the black hole and another for the acceleration. We find that (i) the spacetime of an accelerated static black hole is plagued by either conical singularities or a lack of smoothness and compactness

Patricio S. Letelier; Samuel R. Oliveira

2001-01-01

283

Acceleration and vacuum temperature  

NASA Astrophysics Data System (ADS)

The quantum fluctuations of an accelerated vacuum state, that is, vacuum fluctuations in the presence of a constant electromagnetic field, can be described by the temperature TM. Considering TM for the gyromagnetic factor g=1 we show that TM(g=1)=TU, where TU is the Unruh temperature experienced by an accelerated observer. We conjecture that both particle production and nonlinear field effects inherent in the Unruh accelerated observer case are described by the case g=1 QED of strong fields. We present rates of particle production for g=0, 1, 2 and show that the case g=1 is experimentally distinguishable from g=0, 2. Therefore, either accelerated observers are distinguishable from accelerated vacuum or there is unexpected modification of the theoretical framework.

Labun, Lance; Rafelski, Johann

2012-08-01

284

Open accelerating structures  

SciTech Connect

An ''Open'' Accelerating Structure must first perform the mode matching function of any accelerating structure, i.e., it must couple an incoming free field to an accelerating mode. The simplest open periodic structure that can be considered is a grating. There has been an attempt to employ an inverse Purcell effect by illuminating a grating from directly above with plane parallel light and passing the particles over the surface of the grating at right angles to the lines. Unfortunately, it has been shown by the Lawson theorem that these geometries fail to accelerate relativistic particles. This paper will restate Lawson's theorem but show that it applies only to the simple two-dimensional situation. It is shown that accelerating fields above grating can be made to fall off exponentially from that surface. Several structures are examined that deal with the problem of fields spreading over the whole grating surface.

Palmer, R.B.

1986-12-01

285

The Accelerated Kepler Problem  

E-print Network

The accelerated Kepler problem is obtained by adding a constant acceleration to the classical two-body Kepler problem. This setting models the dynamics of a jet-sustaining accretion disk and its content of forming planets as the disk loses linear momentum through the asymmetric jet-counterjet system it powers. The dynamics of the accelerated Kepler problem is analyzed using physical as well as parabolic coordinates. The latter naturally separate the problem's Hamiltonian into two unidimensional Hamiltonians. In particular, we identify the origin of the secular resonance in the accelerated Kepler problem and determine analytically the radius of stability boundary of initially circular orbits that are of particular interest to the problem of radial migration in binary systems as well as to the truncation of accretion disks through stellar jet acceleration.

Fathi Namouni; Massimiliano Guzzo

2007-05-22

286

LABORATORY I: DESCRIPTION OF MOTION IN ONE DIMENSION  

E-print Network

Lab I - 1 LABORATORY I: DESCRIPTION OF MOTION IN ONE DIMENSION In this laboratory you will measure of any object moving in one dimension using position, time, velocity, and acceleration. · Distinguish and is preceded by the double, vertical lines seen to the left. These laboratory instructions may be unlike any

Minnesota, University of

287

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.

288

BROOKHAVEN LABORATORY  

E-print Network

, and decision-making processes. We will endeavor to support parents in their critical role. 2. Children develop that stimulates academic/cognitive growth, language, social-emotional development and physical developmentBROOKHAVEN NATIONAL LABORATORY Child Development Center Parent Handbook Revised 2009

Ohta, Shigemi

289

Laboratory Buildings.  

ERIC Educational Resources Information Center

The need for flexibility in science research facilities is discussed, with emphasis on the effect of that need on the design of laboratories. The relationship of office space, bench space, and special equipment areas, and the location and distribution of piping and air conditioning, are considered particularly important. This building type study

Barnett, Jonathan

290

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

291

Atomic Molecular and Optical Physics Laboratory Toshiyuki Azuma Division of Genomic Technologies (Center for Life Science Technologies) Piero Carninci  

E-print Network

Radioactive Isotope Physics Laboratory (Nishina Center for Accelerator-Based Science) Hiroyoshi SakuraiAtomic Molecular and Optical Physics Laboratory Toshiyuki Azuma Division of Genomic Technologies (Center for Life Science Technologies) Piero Carninci Computational Astrophysics Laboratory Toshikazu

Fukai, Tomoki

292

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

293

Summary of the 2011 Dielectric Laser Accelerator Workshop  

NASA Astrophysics Data System (ADS)

The first ICFA Mini-Workshop on dielectric laser accelerators (DLA) was held on September 15-16, 2011 at SLAC National Accelerator Laboratory. We present the results of the workshop, and discuss the main conclusions of the Accelerator Applications, Photonics, and Laser Technologies working groups. Over 50 participants from four countries participated, discussing the state of the art in photonic structures, laser science, and nanofabrication as it pertains to laser-driven particle acceleration in dielectric structures. Applications of this new and promising acceleration concept to discovery science and industrial, medical, and basic energy sciences were explored. The DLA community is presently focused on making demonstrations of high gradient acceleration and a compatible atto-second injector source, two critical steps towards realizing the potential of this technology.

Bermel, Peter; Byer, Robert L.; Colby, Eric R.; Cowan, Benjamin M.; Dawson, Jay; Joel England, R.; Noble, Robert J.; Qi, Minghao; Yoder, Rodney B.

2014-01-01

294

Optimization of a small scale reluctance linear solenoid accelerator  

NASA Astrophysics Data System (ADS)

Small scale accelerator technologies provide opportunities in innovative and efficient transportation systems. Accelerator technologies are ever decreasing in size and complexity. The goal of the research was to develop more efficient small scale accelerators by optimizing high current flow through the accelerating solenoid. To do this; low temperature liquid nitrogen cooling systems and Cockcroft-Walton voltage multiplier power supply systems were examined closely to maximize the magnetic field inside the solenoid. Additionally,ferromagnetic fluids were examined in conjunction with these technologies to investigate the possibility of controlled braking of an accelerated object. The experimentation provides a high quality laboratory experiment for undergraduates interested in accelerator physics. Additionally, it provides a useful demonstration apparatus for undergraduate students studying lower division electricity and magnetism courses. A demonstration of the current development on these technologies will be offered at the time of the lecture.

Barrera, Thor; Beard, Robby

2011-04-01

295

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

296

Accelerated stress testing of terrestrial solar cells  

NASA Technical Reports Server (NTRS)

The development of an accelerated test schedule for terrestrial solar cells is described. This schedule, based on anticipated failure modes deduced from a consideration of IC failure mechanisms, involves bias-temperature testing, humidity testing (including both 85-85 and pressure cooker stress), and thermal-cycle thermal-shock testing. Results are described for 12 different unencapsulated cell types. Both gradual electrical degradation and sudden catastrophic mechanical change were observed. These effects can be used to discriminate between cell types and technologies relative to their reliability attributes. Consideration is given to identifying laboratory failure modes which might lead to severe degradation in the field through second quadrant operation. Test results indicate that the ability of most cell types to withstand accelerated stress testing depends more on the manufacturer's design, processing, and worksmanship than on the particular metallization system. Preliminary tests comparing accelerated test results on encapsulated and unencapsulated cells are described.

Lathrop, J. W.; Hawkins, D. C.; Prince, J. L.; Walker, H. A.

1982-01-01

297

Materials for Accelerator Technologies Beyond the Niobium Family  

SciTech Connect

Three niobium-based materials make up the entire present portfolio of superconducting technology for accelerators: Nb-Ti and Nb{sub 3}Sn magnet wires and pure niobium for RF cavities. Because these materials are at a high level of maturity, limits imposed by the boundaries of their superconductivity constrain the energy reach of accelerators to several TeV. We sketch here a plan for targeted development of emerging higher field and higher temperature superconductors that could enable accelerators at significantly higher energies. Niobium-based superconductors are the crucial enablers of present accelerators. The Nb-Ti LHC dipole and quadrupole wires, with transition temperature T{sub c} of 9 K and upper critical field H{sub c2} of 15 T, represent the highest form of superconductor strand art: massive, quarter-ton conductor billets are drawn from 300 mm diameter to {approx}1 mm as a single, multi-kilometer-long piece, while retaining uniformity of the several thousand Nb-Ti filaments to within 5% at the scale of a few micrometers. Strands are twisted into fully transposed cables with virtually no loss, preserving a carefully tuned nanostructure that generates the high flux-pinning forces and high current densities to enable high magnetic fields. Nb{sub 3}Sn, with twice the T{sub c} and H{sub c2}, is now approaching this level of conductor art, where over the last 5 years the LHC Accelerator Research Program (LARP) and the Next European Dipole (NED) program have demonstrated that Nb{sub 3}Sn can be made into 4 meter long quadrupoles with 12 T fields and 250 T/m gradients. Linear accelerators at TJNAF, ORNL (SNS), and under construction for the European XFEL exploit niobium superconducting radio-frequency (SRF) technology, with gradients at {approx}20 MV/m. Tremendous research and development is underway to realize high-power goals for Project X at FNAL and for a possible ILC at 35 MV/m gradients. Despite these impressive achievements, the very maturity of these niobium-based technologies makes them incapable of additional leaps from the several-TeV scale. Nb-Ti is already nearly perfect and operates at the limit of the superconducting phase. Further perfection of Nb cavities and Nb{sub 3}Sn magnets might provide 50 % growth in energy, based on proof-of-principle demonstrations that approach theoretical limits, e.g. 52 MV/m gradient in re-entrant Nb cavities and 18 T dipoles made from Nb3Sn strand. However, operation close to superconducting margins is risky, and cost tradeoffs to execute such a high degrees of perfection are likely to be negative.

Cooley, Lance; Larbalestier, David; Ghosh, Arup; Tollestrup, Alvin; /Fermilab

2009-01-01

298

Reduction of Acceleration to Effectively Microgravity Levels  

NASA Technical Reports Server (NTRS)

Pressure gradients, i.e. pressure head, and buoyancy driven convection can be greatly decreased in experimental systems by acceleration of the laboratory reference frame at a rate consistent with the acceleration due to gravity. This may be done in a number of ways, the best known of which is the use of orbiting spacecraft. Other techniques include the use of aircraft following an appropriate parabolic trajectory or drop towers. The result is an experimental condition in which fluids experience virtually no outside forces relative to the laboratory reference frame. Such conditions are appropriate for the study of processes with diffusion dominated heat and/or mass Under, the study of phase transitions in the absence of pressure gradients, the study of solutal or thermal capillary convection, or containerless processes. Ways of achieving these conditions and complexities that arise in performing experiments in this environment are discussed.

Downey, James Patton

2000-01-01

299

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

300

The MESA accelerator  

NASA Astrophysics Data System (ADS)

The MESA accelerator will operate for particle and nuclear physics experiments in two different modes. A first option is conventional c.w. acceleration yielding 150-200MeV spin-polarized external beam. Second, MESA will be operated as a superconducting multi-turn energy recovery linac (ERL), opening the opportunity to perform experiments with a windowless target with beam current of up to 10 mA. The perspectives for innovative experiments with such a machine are discussed together with a sketch of the accelerator physics issues that have to be solved.

Aulenbacher, Kurt

2013-11-01

301

Accelerator Facilities for Radiation Research  

NASA Technical Reports Server (NTRS)

HSRP Goals in Accelerator Use and Development are: 1.Need for ground-based heavy ion and proton facility to understand space radiation effects discussed most recently by NAS/NRC Report (1996). 2. Strategic Program Goals in facility usage and development: -(1) operation of AGS for approximately 600 beam hours/year; (2) operation of Loma Linda University (LLU) proton facility for approximately 400 beam hours/year; (3) construction of BAF facility; and (4) collaborative research at HIMAC in Japan and with other existing or potential international facilities. 3. MOA with LLU has been established to provide proton beams with energies of 40-250 important for trapped protons and solar proton events. 4. Limited number of beam hours available at Brookhaven National Laboratory's (BNL) Alternating Gradient Synchrotron (AGS).

Cucinotta, Francis A.

1999-01-01

302

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

303

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

304

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

305

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

306

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 chemistry. It is part of the Center for Radiological Research (CRR) -- formerly the Radiological Research Laboratory (RRL) -- of Columbia University, and its operation is supported as 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. Data obtained from experiments using RARAF have been of pragmatic value to radiation protection and neutron therapy. At a more fundamental level, the research protection and neutron therapy. At a more fundamental level, the research at RARAF has provided insight into the biological action of radiation and especially its relation to energy distribution in the cell. High-LET radiations are an agent of special importance because measurable cellular effects can be caused by single particles, eliminating some of the complexities of multievent action and more clearly disclosing basic features. This applies particularly to radiation carcinogenesis.

Hall, E.J.

1989-07-01

307

Laboratory 12 Control Systems Laboratory ECE3557 Laboratory 12  

E-print Network

Laboratory 12 Control Systems Laboratory ECE3557 Laboratory 12 State Feedback Controller of the combined system (i.e., servomotor and flexible link) introduced in the Laboratory 9 (refer to [1 Systems Laboratory ECE3557 · : motor shaft position, measured using channel 1 encoder "ENC1" · : angular

308

Charged particle accelerator grating  

DOEpatents

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

Palmer, R.B.

1985-09-09

309

Non-accelerator experiments  

SciTech Connect

This report discusses several topics which can be investigated without the use of accelerators. Topics covered are: (1) proton decay, (2) atmospheric neutrinos, (3) neutrino detection, (4) muons from Cygnus X-3, and (5) the double-beta decay.

Goldhaber, M.

1986-01-01

310

Wake field acceleration experiments  

SciTech Connect

Where and how will wake field acceleration devices find use for other than, possibly, accelerators for high energy physics. I don't know that this can be responsibly answered at this time. What I can do is describe some recent results from an ongoing experimental program at Argonne which support the idea that wake field techniques and devices are potentially important for future accelerators. Perhaps this will spawn expanded interest and even new ideas for the use of this new technology. The Argonne program, and in particular the Advanced Accelerator Test Facility (AATF), has been reported in several fairly recent papers and reports. But because this is a substantially new audience for the subject, I will include a brief review of the program and the facility before describing experiments. 10 refs., 7 figs.

Simpson, J.D.

1988-01-01

311

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

312

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

313

Motion with Constant Acceleration  

NSDL National Science Digital Library

The purpose of this experiment is to track the motion for an air cart on a sloped track to fall a distance x with constant acceleration a = g sinq. You will verify that the distance and velocity along the incline are given by the parabola x = xo + vo t +1/2at2 and the line v = vo +at. Finally, you will determine the acceleration due to gravity.

Herman, Russell

2008-02-19

314

Accelerating Cosmologies from Compactification  

Microsoft Academic Search

A solution of the (4+n)-dimensional vacuum Einstein equations is found for which spacetime is compactified on a compact hyperbolic manifold of time-varying volume to a flat four-dimensional FLRW cosmology undergoing accelerated expansion in Einstein conformal frame. This shows that the `no-go' theorem forbidding acceleration in `standard' (time-independent) compactifications of string\\/M-theory does not apply to `cosmological' (time-dependent) hyperbolic compactifications.

Paul K. Townsendand; Mattias N. R. Wohlfarth

2003-01-01

315

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

316

Rolamite acceleration sensor  

DOEpatents

A rolamite acceleration sensor is described 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. 6 figures.

Abbin, J.P.; Briner, C.F.; Martin, S.B.

1993-12-21

317

Uniformly accelerated black holes  

Microsoft Academic Search

The static and stationary C-metric are revisited in a generic framework and\\u000atheir interpretations studied in some detail. Specially those with two event\\u000ahorizons, one for the black hole and another for the acceleration. We found\\u000athat: i) The spacetime of an accelerated static black hole is plagued by either\\u000aconical singularities or lack of smoothness and compactness of the

Patricio S. Letelierand; Samuel R. Oliveira

2001-01-01

318

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

319

Nuclear astrophysics studies at LENA: The accelerators  

NASA Astrophysics Data System (ADS)

The accelerators of the Laboratory for Experimental Nuclear Astrophysics (LENA) are described. These include a modified 1 MV Van de Graaff accelerator, a new electron cyclotron resonance (ECR) ion source with its 200 kV acceleration system, and the associated beam transport system. The new ECR ion source utilizes an array of permanent magnets to provide the 87.5 mT solenoidal magnetic field needed for ECR at 2.45 GHz. With 300 W of input radio frequency (RF) power and an extraction voltage of 15 kV, a beam current of 7 mA has been extracted from the source within a measured normalized emittance of 0.19?-mm-mrad. Proton currents in excess of 1 mA can be accelerated to target from the ECR source over the energy range of 90-200 keV. Beam properties have been measured using low-energy resonances in O18(p,?)F19 and Al27(p,?)Si28. The Van de Graaff accelerator can produce 250?A over the energy range 0.3-1 MeV (and somewhat lower currents at lower energies). This new capability will be crucial in the direct search for low-energy resonances in nuclear reactions of astrophysical significance.

Cesaratto, J. M.; Champagne, A. E.; Clegg, T. B.; Buckner, M. Q.; Runkle, R. C.; Stefan, A.

2010-11-01

320

Coherent instabilities at the FNAL Booster  

SciTech Connect

This paper presents results of experimental and theoretical investigations of transverse beam stability at injection to Fermilab Booster and discusses a novel scheme for transition crossing allowing to avoid the longitudinal emittance growth related to the transition. At reduced chromaticity a multibunch high order head-tail mode develops with growth time of 12 turns at fractional part of tune close to zero. An estimate of the growth rate based on known sources of impedance results in significantly smaller value and cannot explain observed instability growth rate.

Lebedev, V.; Burov, A.; Pellico, W.; Yang, X.; /Fermilab

2006-06-01

321

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.

322

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

323

Collider Accelerator Department/ SNS Ring Systems BROOKHA VEN NATIONAL LABORATORY  

E-print Network

-QA-IO. ASTM-A240-89B ASTM-A380-88 ASTM-A480/480M ASTM-E498-90 BNL Seller Quality Assurance Analyzer in the Tracer Probe Mode- Method A Spec.SNS Ring Systems-OO11 Page2 of7 #12;ASTM-A700-8l Standard Practices for Packaging, Marking, and Loading Methods for SteelProductsfor Domestic Shipment ASTM-A249/249M

324

THE ACCELERATOR TUBE DEVELOPMENT PROGRAMME AT DARESBURY LABORATORY  

E-print Network

for construc- ting an organic free tube was concentrated on achie- ving the high precision, atmospheric control- nium to ceramic were soon established. However a harder alloy of titanium which had a better resis to thermal expansion imba- lance and a more reliable method of welding to the end electrode was developed

Boyer, Edmond

325

* Fermi National Accelerator Laboratory FERMILAB-Conf-99/149  

E-print Network

) 4s - 1 TeV. In addition, the priorities of this machine seem to imply operation with or before, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation with a luminosity of 1 fb- `/yr with a center of mass energy of 1 TeV. The machine would utilize superconducting rf

Sen, Tanaji

326

Argonne National Laboratory Physics Division Annual Report 2006.  

National Technical Information Service (NTIS)

This report highlights the activities of the Physics Division of Argonne National Laboratory in 2006. The Division's programs include the operation as a national user facility of ATLAS, the Argonne Tandem Linear Accelerator System, research in nuclear str...

2007-01-01

327

Virtual Laboratories  

E-print Network

At the frontier of most areas in science, computer simulations play a central role. The traditional division of natural science into experimental and theoretical investigations is now completely outdated. Instead, theory, simulation, and experimentation form three equally essential aspects, each with its own unique flavor and challenges. Yet, education in computational science is still lagging far behind, and the number of text books in this area is minuscule compared to the many text books on theoretical and experimental science. As a result, many researchers still carry out simulations in a haphazard way, without properly setting up the computational equivalent of a well equipped laboratory. The art of creating such a virtual laboratory, while providing proper extensibility and documentation, is still in its infancy. A new approach is described here, Open Knowledge, as an extension of the notion of Open Source software. Besides open source code, manuals, and primers, an open knowledge project provides simulated dialogues between code developers, thus sharing not only the code, but also the motivations behind the code.

Piet Hut

2006-10-07

328

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

329

Power-conditioning system for the Advanced Test Accelerator  

Microsoft Academic Search

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 capable of generating electron beam pulses at a 1 kHz rate in a 10 pulse burst, 5 pps average, with a pulse width

M. A. Newton; M. E. Smith; D. L. Birx; D. R. Branum; E. G. Cook; R. L. Copp; F. D. Lee; L. L. Reginato; D. Rogers; G. C. Speckert

1982-01-01

330

Electrostatic Plasma Accelerator (EPA)  

NASA Technical Reports Server (NTRS)

The Electrostatic Plasma Accelerator (EPA) is a thruster concept which promises specific impulse levels between low power arcjets and those of the ion engine while retaining the relative simplicity of the arcjet. The EPA thruster produces thrust through the electrostatic acceleration of a moderately dense plasma. No accelerating electrodes are used and the specific impulse is a direct function of the applied discharge voltage and the propellant atomic mass. The goal of the present program is to demonstrate feasibility of the EPA thruster concept through experimental and theoretical investigations of the EPA acceleration mechanism and discharge chamber performance. Experimental investigations will include operating the test bed ion (TBI) engine as an EPA thruster and parametrically varying the thruster geometry and operating conditions to quantify the electrostatic plasma acceleration effect. The theoretical investigations will include the development of a discharge chamber model which describes the relationships between the engine size, plasma properties, and overall performance. For the EPA thruster to be a viable propulsion concept, overall thruster efficiencies approaching 30% with specific impulses approaching 1000 s must be achieved.

Brophy, John R.; Aston, Graeme

1989-01-01

331

Fermi acceleration in astrophysical jets  

E-print Network

We consider the acceleration of energetic particles by Fermi processes (i.e., diffusive shock acceleration, second order Fermi acceleration, and gradual shear acceleration) in relativistic astrophysical jets, with particular attention given to recent progress in the field of viscous shear acceleration. We analyze the associated acceleration timescales and the resulting particle distributions, and discuss the relevance of these processes for the acceleration of charged particles in the jets of AGNs, GRBs and microquasars, showing that multi-component powerlaw-type particle distributions are likely to occur.

Frank M. Rieger; Valenti Bosch-Ramon; Peter Duffy

2006-10-05

332

Microelectromechanical acceleration-sensing apparatus  

DOEpatents

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

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

2006-12-12

333

Studies of accelerated compact toruses  

SciTech Connect

In an earlier publication we considered acceleration of plasma rings (Compact Torus). Several possible accelerator configurations were suggested and the possibility of focusing the accelerated rings was discussed. In this paper we consider one scheme, acceleration of a ring between coaxial electrodes by a B/sub theta/ field as in a coaxial rail-gun. If the electrodes are conical, a ring accelerated towards the apex of the cone undergoes self-similar compression (focusing) during acceleration. Because the allowable acceleration force, F/sub a/ = kappaU/sub m//R where (kappa < 1), increases as R/sup -2/, the accelerating distance for conical electrodes is considerably shortened over that required for coaxial electrodes. In either case, however, since the accelerating flux can expand as the ring moves, most of the accelerating field energy can be converted into kinetic energy of the ring leading to high efficiency.

Hartman, C.W.; Eddleman, J.; Hammer, J.H.

1983-01-04

334

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

335

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.

2012-04-27

336

LLNL multi-user tandem laboratory  

NASA Astrophysics Data System (ADS)

The Physics Department at Lawrence Livermore National Laboratory (LLNL) is building a new tandem Van de Graaff laboratory for nuclear physics and applied physics and technology programs. The laboratory has been funded by a coalition of users including several LLNL divisions, Sandia National Laboratories Livermore, and the University of California. The tandem is the former University of Washington injector FN. The accelerator is upgraded with a Pelletron charging system, Dowlish spiral inclined field beam tubes and SF 6 insulation. The laboratory incorporates several novel design concepts. Initial operation will be in June, 1987 with full operation in October, 1987. Design features, radiological controls, computer assisted operation, and experimental facilities of the laboratory are discussed.

Proctor, I. D.; Davis, J. C.; Eaton, M. R.; Garibaldi, J. L.; Moore, T. L.; Schumacher, B. J.; Southon, J. R.; Zimmerman, T. A.

1988-05-01

337

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

338

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

339

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

340

Accelerating the culture change!  

PubMed

Exide Electronics, a major supplier of uninterruptible power system equipment, embarked on a journey of changing a culture to improve quality, enhance customer responsiveness, and reduce costs. This case study examines the evolution of change over a period of seven years, with particular emphasis on the most recent years, 1992 through 1995. The article focuses on the Raleigh plant operations and describes how each succeeding year built on the successes and fixed the shortcomings of the prior years to accelerate the culture change, including corrective action and continuous improvement processes, organizational structures, expectations, goals, achievements, and pitfalls. The real challenge to changing the culture was structuring a dynamic approach to accelerate change! The presentation also examines how the evolutionary process itself can be created and accelerated through ongoing communication, regular feedback of progress and goals, constant evaluation and direction of the process, and measuring and paying for performance. PMID:10162360

Klunk, S W; Panetta, J; Wooten, J

1996-11-01

341

Superconducting traveling wave accelerators  

NASA Astrophysics Data System (ADS)

The applicability of superconductivity to traveling wave accelerators is considered. Unlike CW operation of a superconducting standing wave or circulating wave accelerator section, which requires improvement factors (superconductor conductivity divided by copper conductivity) of about 10(6) in order to be of practical use, a Superconducting Traveling wave factors as low as about 10(3), which are attainable with niobium or lead at 4.2K, the temperature of liquid helium at atmospheric pressure. Changing from a copper traveling wave accelerator to SUTRA achieves the following: (1) for a given gradient SUTRA reduces the peak and average power requirements typically byu a factor of 2; (2) SUTRA reduces the peak power still further because it enables us to increase the filling time and thus trade pulse width for gradient; (3) SUTRA makes possible a reasonably long section at higher frequencies; and (4) SUTRA makes possible recirculation without additional RF average power.

Farkas, Z. D.

1984-11-01

342

Accelerator technology program. Progress report, January-June 1981  

SciTech Connect

This report covers the activities of Los Alamos National Laboratory's Accelerator Technology Division during the first 6 months of calendar 1981. We discuss the Division's major projects, which reflect a variety of applications and sponsors. The varied technologies concerned with the Proton Storage ring are concerned with the Proton Storage Ring are continuing and are discussed in detail. For the racetrack microtron (RTM) project, the major effort has been the design and construction of the demonstration RTM. Our development of the radio-frequency quadrupole (RFQ) linear accelerator continues to stimulate interest for many possible applications. Frequent contacts from other laboratories have revealed a wide acceptance of the RFQ principle in solving low-velocity acceleration problems. In recent work on heavy ion fusion we have developed ideas for funneling beams from RFQ linacs; the funneling process is explained. To test as many aspects as possible of a fully integrated low-energy portion of a Pion generator for Medical Irradiation (PIGMI) Accelerator, a prototype accelerator was designed to take advantage of several pieces of existing accelerator hardware. The important principles to be tested in this prototype accelerator are detailed. Our prototype gyrocon has been extensively tested and modified; we discuss results from our investigations. Our work with the Fusion Materials Irradiation Test Facility is reviewed in this report.

Knapp, E.A.; Jameson, R.A. (comps.)

1982-05-01

343

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

344

Micromachined Ion Accelerators  

NASA Technical Reports Server (NTRS)

Proposed ion accelerators made by micromachining techniques. Advantages include small size and weight, modularity, and compatibility with integrated circuits. Used as sources of ion beams for industrial processes. Ion accelerator of this type combined with integrated electronic control and power circuitry, plus similarly miniaturized valves and other mechanisms for regulating flow of gas used to generate ions - all micromachined on single chip. Provides flexibility for tailoring characteristics of ion sources for specific applications; for example, construct array of many such devices to obtain large ion source or position multiple devices to obtain desired ion-beam pattern in processing chamber.

Brophy, John; Mueller, Juergen; Polk, James; Blandino, John

1996-01-01

345

Interfacing to accelerator instrumentation  

SciTech Connect

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

Shea, T.J.

1995-12-31

346

Paired Accelerated Frames  

E-print Network

The geometrical and quantum mechanical basis for Davies' and Unruh's acceleration temperature is traced to a type of quantum mechanical (``achronal'') spin. Its existence and definition are based on pairs of causally disjoint accelerated frames. For bosons the expected spin vector of monochromatic particles is given by the ``Planckian power'' and the ``r.m.s. thermal fluctuation'' spectra. Under spacetime translation the spin direction precesses around that ``Planckian'' vector. By exhibiting the conserved achronal spin four-current, we extend the identification of achronal spin from single quanta to multiparticle systems. Total achronal spin conservation is also shown to hold, even in the presence of quadratic interactions.

Ulrich H. Gerlach

1999-10-28

347

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

348

High intensity hadron accelerators  

SciTech Connect

This rapporteur report consists mainly of two parts. Part I is an abridged review of the status of all High Intensity Hadron Accelerator projects in the world in semi-tabulated form for quick reference and comparison. Part II is a brief discussion of the salient features of the different technologies involved. The discussion is based mainly on my personal experiences and opinions, tempered, I hope, by the discussions I participated in in the various parallel sessions of the workshop. In addition, appended at the end is my evaluation and expression of the merits of high intensity hadron accelerators as research facilities for nuclear and particle physics.

Teng, L.C.

1989-05-01

349

Photocathodes in accelerator applications  

SciTech Connect

Some electron accelerator applications require bursts of short pulses at high microscopic repetition rates and high peak brightness. A photocathode, illuminated by a mode-locked laser, is well suited to filling this need. The intrinsic brightness of a photoemitter beam is high; experiments are under way at Los Alamos to study the brightness of short bunches with high space charge after acceleration. A laser-illuminated Cs/sub 3/Sb photoemitter is located in the first rf cavity of an injector linac. Diagnostics include a pepper-pot emittance analyzer, a magnetic spectrometer, and a streak camera.

Fraser, J.S.; Sheffield, R.L.; Gray, E.R.; Giles, P.M.; Springer, R.W.; Loebs, V.A.

1987-01-01

350

Proposed structure for a crossed-laser beam, GeV per meter gradient, vacuum electron linear accelerator  

E-print Network

accelerator Y. C. Huang, D. Zheng, W. M. Tulloch, and R. L. Byer Edward Ginzton Laboratory, Stanford We propose a dielectric-based, multistaged, laser-driven electron linear accelerator structure operating in a vacuum that is capable of accelerating electrons to 1 TeV in 1 km. Our study shows that a Ge

Byer, Robert L.

351

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

352

Report on accelerated corrosion studies.  

SciTech Connect

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 electrical components exposed to environmental conditions representative of homes constructed with problem drywall. The conditions of the accelerated testing were chosen to produce corrosion product growth that would be consistent with long-term exposure to environments containing humidity and parts per billion (ppb) levels of hydrogen sulfide (H{sub 2}S) that are thought to have been the source of corrosion in electrical components from affected homes. This report documents the test set-up, monitoring of electrical performance of powered electrical components during the exposure, and the materials characterization conducted on wires, screws, and contact plates from selected electrical components. No degradation in electrical performance (measured via voltage drop) was measured during the course of the 8-week exposure, which was approximately equivalent to 40 years of exposure in a light industrial environment. Analyses show that corrosion products consisting of various phases of copper sulfide, copper sulfate, and copper oxide are found on exposed surfaces of the conductor materials including wires, screws, and contact plates. The morphology and the thickness of the corrosion products showed a range of character. In some of the copper wires that were observed, corrosion product had flaked or spalled off the surface, exposing fresh metal to the reaction with the contaminant gasses; however, there was no significant change in the wire cross-sectional area.

Mowry, Curtis Dale; Glass, Sarah Jill; Sorensen, Neil Robert

2011-03-01

353

The Physics Hypertextbook: Acceleration  

NSDL National Science Digital Library

This online tutorial offers support in understanding acceleration from both a conceptual and a quantitative framework. It features a discussion of key concepts, practice problems with answers provided, and a list of links to related activities for high school students. This resource is part of an online textbook in introductory physics.

Elert, Glenn

2006-10-19

354

Precocity and Acceleration.  

ERIC Educational Resources Information Center

This article discusses how schools can best meet the needs of precocious children by giving them access to higher level and more challenging instructional materials. Findings from a study of 40 precocious third and fourth graders are described and the benefits of acceleration are highlighted, particularly grade advancement and advanced placement

Feldhusen, John F.

2003-01-01

355

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

356

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

357

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

358

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

359

Galactic Acceleration Phenomena  

NASA Astrophysics Data System (ADS)

I will review the current status of our observational knowledge of prominent classes of particle accelerators in the Galaxy, especially shell-type supernova remnants (SNRs) and pulsar wind nebulae. I will highlight in particular the contribution of the recent improvement in sensitivity of very-high-energy (VHE) gamma-ray observations, which are currently the most direct probe of particle acceleration in the Galaxy up to energies of several hundreds of TeV. Shell-type SNRs have long been proposed as sources of the Galactic cosmic rays, through Fermi acceleration at their outer blast waves. In recent years, X-ray observations have revealed very thin, non-thermal rims in many young SNRs, and I will discuss the implications of these observations of synchrotron emission from accelerated electrons, in particular for magnetic field amplification and the maximum accelerated particle energy attainable in these shock waves. I will then review the current status of the evidence for high-energy nuclei in these objects, especially in view of recent VHE gamma-ray observations. I will summarise current uncertainties and outline prospects for future progress through greater multi-wavelength studies. As a result of the survey of the Galactic plane in VHE gamma-rays undertaken by the HESS experiment, the most numerous class of identified Galactic VHE sources is currently that of pulsar wind nebulae (PWNe), also known as plerionic SNRs. In these objects, the VHE gamma-ray emission is generally thought to be dominantly leptonic, and I will outline the complementarity between the results of these observations and the better-known X-ray observations of synchrotron emission. I will discuss the evolutionary problems posed by the large observed sizes of several of the new gamma-ray pulsar wind nebulae, and outline prospects for progress in our understanding of these objects.

Gallant, Y. A.

2006-08-01

360

Accelerator applications of engineered media  

NASA Astrophysics Data System (ADS)

Material properties are vital for the field of accelerator R&D. Euclid Techlabs in collaboration with the Argonne Wakefield Accelerator facility team has investigated accelerator applications of metamaterials, photonic band gap structures, nonlinear, paramagnetic and ferroelectric materials. In this paper we will present results of our work on advanced accelerating structures and accelerating applications of engineered materials. These will include wakefield test of a photonic band gap accelerating structure, design of a dielectric loaded structure with built in tunable paramagnetic absorption mechanism and beam diagnostics applications of metamaterials.

Antipov, Sergey

2010-11-01

361

An accelerating section with a constant acceleration rate  

SciTech Connect

An accelerating section with varying cross section and 2..pi../3 working oscillation phase has been designed, built, and tested. The experimental results at low powers and in the acceleration mode are in satisfactory agreement with calculated results.

Zykov, A.I.; Kondratenko, V.V.; Kramskoi, G.D.; Mondrus, I.N.; Ryabtsov, A.V.; Smirnov, V.L.; Terekhov, B.A.; Chikatash, I.A.

1982-11-01

362

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

363

Accelerators for heavy-charged-particle radiation therapy.  

PubMed

This paper focuses on current and future designs of medical hadron accelerators for treating cancers and other diseases. Presently, five vendors and several national laboratories have produced heavy-particle medical accelerators for accelerating nuclei from hydrogen (protons) up through carbon and oxygen. Particle energies are varied to control the beam penetration depth in the patient. As of the end of 2006, four hospitals and one clinic in the United States offer proton treatments; there are five more such facilities in Japan. In most cases, these facilities use accelerators designed explicitly for cancer treatments. The accelerator types are a combination of synchrotrons, cyclotrons, and linear accelerators; some carry advanced features such as respiration gating, intensity modulation, and rapid energy changes, which contribute to better dose conformity on the tumor when using heavy charged particles. Recent interest in carbon nuclei for cancer treatment has led some vendors to offer carbon-ion and proton capability in their accelerator systems, so that either ion can be used. These features are now being incorporated for medical accelerators in new facilities. PMID:17668952

Coutrakon, George B

2007-08-01

364

Development of a tritium accelerator mass spectrometer  

SciTech Connect

An accelerator mass spectrometer (AMS) for direct atom counting of tritium ahs been developed using the Crocker Nuclear Laboratory's (CNL) 76 sector-focused cyclotron. Tritons were accelerated to 6.2 MeV and detected in a silicon {Delta}E-E charged particle telescope. An efficiency for detection of 2.4 x 10/sup -5/ was achieved with the smallest sample detected containing 2.6 mBq (70 fCi) of tritium at a T/H ratio of 3.7 x 10/sup 13/. Counting times were 3 to 6 minutes with smaller samples requiring less time. This technique greatly reduces counting times and sample sizes from that required in existing {Beta}-decay detection of ambient levels of tritium.

Cutchin, J.; King, S.; Phillips, G.; August, R.; Gerber, J.; Castaneda, C. (U.S. Naval Research Lab., Washington, DC (US))

1988-02-01

365

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

366

Precise charge measurement for laser plasma accelerators  

NASA Astrophysics Data System (ADS)

A comprehensive study of charge diagnostics was conducted to verify their validity for measuring electron beams produced by laser plasma accelerators (LPAs). 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. Using an integrating current transformer as a calibration reference, the sensitivity of the Lanex Fast was found to decrease by 1% per 100 MeV increase of the energy. By using electron beams from LPA, cross calibrations of the charge were carried out with an integrating current transformer, scintillating screen (Lanex from Kodak), and activation based measurement. The diagnostics agreed within 8%, showing that they all can provide accurate charge measurements for LPAs provided necessary cares.

Nakamura, Kei; Gonsalves, Anthony; Lin, Chen; Sokollik, Thomas; Shiraishi, Satomi; van Tilborg, Jeroen; Smith, Alan; Rodgers, Dave; Donahue, Rick; Byrne, Warren; Leemans, Wim

2011-11-01

367

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 1percent 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/mm2 and 0.4 pC/ps/mm2, 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 percent.

Nakamura, K.; Gonsalves, A. J.; Lin, C.; Sokollik, T.; Smith, A.; Rodgers, D.; Donahue, R.; Bryne, W.; Leemans, W. P.

2010-06-01

368

Advanced accelerator simulation research: miniaturizing accelerators from kilometers to meters  

E-print Network

as well as more mainstream problems in accelerator physics, such as the electron cloud instability in this quest. One of the goals of the SciDAC Accelerator Modeling Project is to develop code and software-scale experiments. We describe the existing hierarchy of software tools for modelling advanced accelerators, how

Geddes, Cameron Guy Robinson

369

Measurement of the electroweak top quark production cross section and the CKM matrix element Vtb with the D0 experiment  

Microsoft Academic Search

At particle accelerators the Standard Model has been tested and will be tested further to a great precision. The data analyzed in this thesis have been collected at the world's highest energetic-collider, the Tevatron, located at the Fermi National Accelerator Laboratory (FNAL) in the vicinity of Chicago, IL, USA. There, protons and antiprotons are collided at a center-of-mass energy of

Matthias Kirsch

2009-01-01

370

Creep Laboratory manual  

Microsoft Academic Search

A manual for the NPL Creep Laboratory, a collective name given to two testing laboratories, the Uniaxial Creep Laboratory and the Advanced High Temperature Mechanical Testing Laboratory, is presented. The first laboratory is devoted to uniaxial creep testing and houses approximately 50 high sensitivity creep machines including 10 constant stress cam lever machines. The second laboratory houses a low cycle

S. Osgerby; M. S. Loveday

1992-01-01

371

ELECTRON INJECTION INTO CYCLIC ACCELERATOR USING  

E-print Network

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

372

Acceleration and Classical Electromagnetic Radiation  

E-print Network

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

E. N. Glass

2008-01-09

373

Accelerated Insertion of Materials - Composites.  

National Technical Information Service (NTIS)

The objective of the Accelerated Insertion of Materials - Composites (AIM-C) program is to develop and validate new approaches for materials development that will accelerate the insertion of materials into production hardware.

G. Havskjold

2001-01-01

374

How amines accelerate delignification  

SciTech Connect

In soda pulping with primary aliphatic amines and diamines, the rate of delignification varies with the initial molar amount of amine. At a given temperature and time, the reciprocal of the kappa number of a pulp and the number of moles of amine initially introduced show a linear relationship that is valid at concentrations of amine below those at which phase separation occurs. On a molar basis, primary amines were six to ten times less efficient than hydrosulfide ion as accelerators of delignification, and 400-1200 times less efficient than anthraquinone. We propose that the primary role of the amine is to accelerate the delignification reaction through a chemical rather than physical mechanism. (Refs. 10).

Abbot, J.; Bolker, H.I.

1982-02-01

375

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

376

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

377

Ion sources for accelerators  

NASA Astrophysics Data System (ADS)

A survey of different types of ion sources used for accelerator applications is given. Typical problems like the source life time, or the special need for technical solutions for specific elements will demonstrate the advantage of each type of ion source. In any case reliability is a main topic. Besides the plasma generation of the desired element, beam formation and beam transport to the accelerator are discussed. The influence of space charge on the beam transport can be of great importance if there is no space-charge compensation. Typical results achieved at GSI will be given for the following source types: Penning Ion Source (PIG), Electron Cyclotron Resonance (ECR), Cold or Hot Reflex Discharge Ion Source (CHORDIS), Multicusp Ion Source (MUCIS) and MEVVA.

Spdtke, P.; Bossler, J.; Emig, H.; Leible, K. D.; Mhle, C.; Schulte, H.; Tinschert, K.

1998-04-01

378

SUPERDIFFUSIVE SHOCK ACCELERATION  

SciTech Connect

The theory of diffusive shock acceleration is extended to the case of superdiffusive transport, i.e., when the mean square deviation grows proportionally to t{sup {alpha}}, with {alpha} > 1. Superdiffusion can be described by a statistical process called Levy random walk, in which the propagator is not a Gaussian but it exhibits power-law tails. By using the propagator appropriate for Levy random walk, it is found that the indices of energy spectra of particles are harder than those obtained where a normal diffusion is envisaged, with the spectral index decreasing with the increase of {alpha}. A new scaling for the acceleration time is also found, allowing substantially shorter times than in the case of normal diffusion. Within this framework we can explain a number of observations of flat spectra in various astrophysical and heliospheric contexts, for instance, for the Crab Nebula and the termination shock of the solar wind.

Perri, S.; Zimbardo, G. [Dipartimento di Fisica, Universita della Calabria, Ponte P. Bucci Cubo 31C, I-87036 Rende (Italy)

2012-05-10

379

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

380

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

381

Pulsed electromagnetic gas acceleration  

NASA Technical Reports Server (NTRS)

Experimental data were combined with one-dimensional conservation relations to yield information on the energy deposition ratio in a parallel-plate accelerator, where the downstream flow was confined to a constant area channel. Approximately 70% of the total input power was detected in the exhaust flow, of which only about 20% appeared as directed kinetic energy, thus implying that a downstream expansion to convert chamber enthalpy into kinetic energy must be an important aspect of conventional high power MPD arcs. Spectroscopic experiments on a quasi-steady MPD argon accelerator verified the presence of A(III) and the absence of A(I), and indicated an azimuthal structure in the jet related to the mass injection locations. Measurements of pressure in the arc chamber and impact pressure in the exhaust jet using a piezocrystal backed by a Plexiglas rod were in good agreement with the electromagnetic thrust model.

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

1971-01-01

382

Exploring Acceleration with an Android  

NSDL National Science Digital Library

Students conduct an experiment to study the acceleration of a mobile Android device. During the experiment, they run an application created with MIT's App Inventor that monitors linear acceleration in one-dimension. Students use an acceleration vs. time equation to construct an approximate velocity vs. time graph. Students will understand the relationship between the object's mass and acceleration and how that relates to the force applied to the object, which is Newton's second law of motion.

IMPART RET Program, College of Information Science & Technology,

383

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."

384

Modulational effects in accelerators  

SciTech Connect

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

Satogata, T.

1997-12-01

385

A laser accelerator  

Microsoft Academic Search

We show that a laser can efficiently accelerate charged particles if a magnetic field is introduced to improve the coupling\\u000a between the particle and the wave. Solving the relativistic equations of motion for an electron in a uniform magnetic field\\u000a and superposed, circularly polarized electromagnetic wave, we find that in energy-position phase space an electron traces\\u000a out a curtate cycloid:

W. B. Colson; S. K. Ride

1979-01-01

386

Dielectric Stimulated Wakefield Accelerator  

Microsoft Academic Search

Wakefield acceleration in a dielectric-loaded waveguide has been previously analyzed and tested.(M. Rosing and W. Gai, Phys. Rev. D 42), 1829 (1990).^,3 We note that a dielectric geometry can be found in which the wakefield is a nearly-periodic function of z - ct, and that the multi-mode wakefield period and interbunch spacing can coincide. Thus, superposition of wakes can occur.

T. B. Zhang; J. L. Hirshfield; T. C. Marshall; B. Hafizi

1997-01-01

387

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

388

Classifier Acceleration by Imitation  

Microsoft Academic Search

\\u000a This paper presents a framework named Classifier Molding that imitates arbitrary classifiers by linear regression trees\\u000a so as to accelerate classification speed. This framework requires an accurate (but slow) classifier and large amount of training\\u000a data. As an example of accurate classifier, we used the Compound Similarity Method (CSM) for Industrial Ink Jet Printer (IIJP)\\u000a character recognition problem. The input-output

Takahiro Ota; Toshikazu Wada; Takayuki Nakamura

2010-01-01

389

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

390

Electrostatic Plasma Accelerator (EPA)  

NASA Technical Reports Server (NTRS)

The application of electric propulsion to communications satellites, however, has been limited to the use of hydrazine thrusters with electric heaters for thrust and specific impulse augmentation. These electrothermal thrusters operate at specific impulse levels of approximately 300 s with heater powers of about 500 W. Low power arcjets (1-3 kW) are currently being investigated as a way to increase specific impulse levels to approximately 500 s. Ion propulsion systems can easily produce specific impulses of 3000 s or greater, but have yet to be applied to communications satellites. The reasons most often given for not using ion propulsion systems are their high level of overall complexity, low thrust with long burn times, and the difficulty of integrating the propulsion system into existing commercial spacecraft busses. The Electrostatic Plasma Accelerator (EPA) is a thruster concept which promises specific impulse levels between low power arcjets and those of the ion engine while retaining the relative simplicity of the arcjet. The EPA thruster produces thrust through the electrostatic acceleration of a moderately dense plasma. No accelerating electrodes are used and the specific impulse is a direct function of the applied discharge voltage and the propellant atomic mass.

Brophy, John R.; Aston, Graeme

1995-01-01

391

Accelerated Profile HMM Searches.  

PubMed

Profile hidden Markov models (profile HMMs) and probabilistic inference methods have made important contributions to the theory of sequence database homology search. However, practical use of profile HMM methods has been hindered by the computational expense of existing software implementations. Here I describe an acceleration heuristic for profile HMMs, the "multiple segment Viterbi" (MSV) algorithm. The MSV algorithm computes an optimal sum of multiple ungapped local alignment segments using a striped vector-parallel approach previously described for fast Smith/Waterman alignment. MSV scores follow the same statistical distribution as gapped optimal local alignment scores, allowing rapid evaluation of significance of an MSV score and thus facilitating its use as a heuristic filter. I also describe a 20-fold acceleration of the standard profile HMM Forward/Backward algorithms using a method I call "sparse rescaling". These methods are assembled in a pipeline in which high-scoring MSV hits are passed on for reanalysis with the full HMM Forward/Backward algorithm. This accelerated pipeline is implemented in the freely available HMMER3 software package. Performance benchmarks show that the use of the heuristic MSV filter sacrifices negligible sensitivity compared to unaccelerated profile HMM searches. HMMER3 is substantially more sensitive and 100- to 1000-fold faster than HMMER2. HMMER3 is now about as fast as BLAST for protein searches. PMID:22039361

Eddy, Sean R

2011-10-01

392

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

393

Linear accelerator output variability.  

PubMed

The Wellington Cancer Centre is equipped with two matched linear accelerators (Varian 2100CD) linear accelerators (identified as SN1027 and SN42). Each morning, before treatments commence, a radiation therapist carries out an output constancy check of the radiation output and every fortnight a physicist measures, in a phantom, the delivered radiation dose to check on the machine calibration. The daily output checks have been recorded into a database (Argus QA for Radiation Oncology) since August 1997 and in June 1998 the fortnightly calibration measurements were added. The information in the database, up to April 2003, has been analysed to consider the quality of the daily constancy checks as compared with the fortnightly calibration measurements and whether the data contains useful information on machine performance. After allowance for the effects of machine recalibration the fortnightly calibration measurements had an average standard deviation of 0.4% and the daily constancy checks 0.8%. The daily constancy checks had a greater number of large deviations than would be expected assuming a normal distribution and were not a good predictor of the need for a recalibration. The fortnightly calibration measurements with a much lower spread give a reliable indication of the need for a recalibration allowing the adoption of a +/- 1% tolerance. Over the period analysed one accelerator (SN42) was relatively stable with the output generally drifting between +/- 1% while the other (SN1027) had a consistent increase in the average output of about 2.5% per year. PMID:15580846

Luketina, I A; Greig, L

2004-09-01

394

Accelerated Profile HMM Searches  

PubMed Central

Profile hidden Markov models (profile HMMs) and probabilistic inference methods have made important contributions to the theory of sequence database homology search. However, practical use of profile HMM methods has been hindered by the computational expense of existing software implementations. Here I describe an acceleration heuristic for profile HMMs, the multiple segment Viterbi (MSV) algorithm. The MSV algorithm computes an optimal sum of multiple ungapped local alignment segments using a striped vector-parallel approach previously described for fast Smith/Waterman alignment. MSV scores follow the same statistical distribution as gapped optimal local alignment scores, allowing rapid evaluation of significance of an MSV score and thus facilitating its use as a heuristic filter. I also describe a 20-fold acceleration of the standard profile HMM Forward/Backward algorithms using a method I call sparse rescaling. These methods are assembled in a pipeline in which high-scoring MSV hits are passed on for reanalysis with the full HMM Forward/Backward algorithm. This accelerated pipeline is implemented in the freely available HMMER3 software package. Performance benchmarks show that the use of the heuristic MSV filter sacrifices negligible sensitivity compared to unaccelerated profile HMM searches. HMMER3 is substantially more sensitive and 100- to 1000-fold faster than HMMER2. HMMER3 is now about as fast as BLAST for protein searches. PMID:22039361

Eddy, Sean R.

2011-01-01

395

A novel rotary acceleration sensor  

Microsoft Academic Search

The authors developed a new type of rotary acceleration sensor. It has the capability to sense an angular acceleration independently to the rotational speed and has an unlimited rotation range. The authors believe that this sensor can be used in robust motor control, vibration control, and any other application where a reliable acceleration signal is needed. The sensor's structure and

Ivan Godler; Akira Akahane; Kouhei Ohnishi; Tadashi Yamashita

1995-01-01

396

Solar Flares and particle acceleration  

E-print Network

Solar Flares and particle acceleration Eduard Kontar School of Physics and Astronomy University of Glasgow, UK STFC Summer School, Armagh, 2012 #12;Solar flares: basics X-raysradiowavesParticles1AU Figure and accelerated particles #12;Solar flares and accelerated particles From Emslie et al., 2004, 2005 Free magnetic

397

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

398

was a decisive one as in the studies of hyperon rare decays at FNAL (E715 and E761 experi ments), in the studies of the muon catalyzed nuclear fusion at PSI, or in the studies of exotic  

E-print Network

­ ments), in the studies of the muon catalyzed nuclear fusion at PSI, or in the studies of exotic nuclei nuclear fusion reactions was successfully carried out in the muon channel of the SC. The muon beam is also intensity (1¯A) make this accelerator valuable even in the up­to­date nuclear studies. For example

Titov, Anatoly

399

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

400

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

401

Virtual reality visualization of accelerator magnets  

SciTech Connect

The authors describe the use of the CAVE virtual reality visualization environment as an aid to the design of accelerator magnets. They have modeled an elliptical multipole wiggler magnet being designed for use at the Advanced Photon Source at Argonne National Laboratory. The CAVE environment allows the authors to explore and interact with the 3-D visualization of the magnet. Capabilities include changing the number of periods the magnet displayed, changing the icons used for displaying the magnetic field, and changing the current in the electromagnet and observing the effect on the magnetic field and particle beam trajectory through the field.

Huang, M.; Papka, M.; DeFanti, T. [Univ. of Illinois, Chicago, IL (United States). Electronic Visualization Lab.; Levine, D.; Turner, L. [Argonne National Lab., IL (United States); Kettunen, L. [Tampere Univ. of Technology (Finland). Lab. of Electricity and Magnetism

1995-05-01

402

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

403

Visualization of Current Sheet Canting in a Pulsed Plasma Accelerator  

E-print Network

.Y. Choueiri Electric Propulsion and Plasma Dynamics Laboratory (EPPDyL) Mechanical and Aerospace Engineering which entrains gas as it propagates along the acceleration channel, acting as an electromagnetic Propulsion Con- ference, Kitakyushu, JAPAN, October 17-21,1999. sweeping characteristics is essential

Choueiri, Edgar

404

Towards Dense Linear Algebra for Hybrid GPU Accelerated Manycore Systems  

E-print Network

Dongarra1,2,3 , and Marc Baboulin1,4 1 University of Tennessee (USA) 2 Oak Ridge National Laboratory (USA) 3 University of Manchester (UK) 4 University of Coimbra (Portugal) October 14, 2008 Abstract. If multicore is a disruptive technology, try to imagine hybrid multicore systems enhanced with accelerators

Dongarra, Jack

405

Non-dimensional Performance Trends of a Pulsed Plasma Accelerator  

E-print Network

th International Electric Propulsion Conference, Princeton University October 31 ­ November 4, 2005 John W. Berkery and Edgar Y. Choueiri Electric Propulsion and Plasma Dynamics Laboratory (EPPDy, has a large influence on the performance of the device as a plasma accelerator. Nomenclature ¯c Ion

Choueiri, Edgar

406

Initial tests of the magnetic spectrometer at the TANDAR accelerator  

Microsoft Academic Search

A new magnetic spectrometer has started operating at the 20 UD tandem accelerator of the TANDAR laboratory. A large acceptance angle and the ability to handle a broad range of energies and masses are its main characteristics. The associated detection system consists of a multiwire vertical drift chamber, an ionization chamber and a plastic scintillator. The complete device was tested

E. Achterberg; A. J Pacheco; M di Tada; J. O Fernndez Niello; R. Liberman; G. V. Mart; M. Ramrez; J. E Testoni; K. Koide

1995-01-01

407

Acceleration of Positive and Negative Ions at Tens of Torr  

Microsoft Academic Search

Our laboratory is undertaking the production of energetic neutralized beams via an rf quadrupole (RFQ). These are defined as beams containing positive and negative ions at overlapping locations or beams of fast neutrals formed from the recombination of positive and negative ions. As a preface and complement to the RFQ experiments, we are conducting simple proof-of-principle experiments to alternately accelerate

Nathaniel Hicks; George Paskal; Jacqueline Pau; Glenn Rosenthal; Alfred Wong

1999-01-01

408

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

409

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

410

Separations technology development to support accelerator-driven transmutation concepts  

SciTech Connect

This is the final report of a one-year Laboratory-Directed Research and Development (LDRD) Project at the Los Alamos National Laboratory (LANL). This project investigated separations technology development needed for accelerator-driven transmutation technology (ADTT) concepts, particularly those associated with plutonium disposition (accelerator-based conversion, ABC) and high-level radioactive waste transmutation (accelerator transmutation of waste, ATW). Specific focus areas included separations needed for preparation of feeds to ABC and ATW systems, for example from spent reactor fuel sources, those required within an ABC/ATW system for material recycle and recovery of key long-lived radionuclides for further transmutation, and those required for reuse and cleanup of molten fluoride salts. The project also featured beginning experimental development in areas associated with a small molten-salt test loop and exploratory centrifugal separations systems.

Venneri, F.; Arthur, E.; Bowman, C. [and others

1996-10-01

411

Development of ADS virtual accelerator based on XAL  

NASA Astrophysics Data System (ADS)

XAL is a high level accelerator application framework that was originally developed by the Spallation Neutron Source (SNS), Oak Ridge National Laboratory. It has an advanced design concept and has been adopted by many international accelerator laboratories. Adopting XAL for ADS is a key subject in the long term. This paper will present the modifications to the original XAL applications for ADS. The work includes a proper relational database schema modification in order to better suit the requirements of ADS configuration data, redesigning and re-implementing db2xal application, and modifying the virtual accelerator application. In addition, the new device types and new device attributes for ADS online modeling purpose are also described here.

Wang, Peng-Fei; Cao, Jian-She; Ye, Qiang

2014-07-01

412

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

413

KEKB accelerator control system  

NASA Astrophysics Data System (ADS)

The KEKB accelerator control system including a control computer system, a timing distribution system, and a safety control system are described. KEKB accelerators were installed in the same tunnel where the TRISTAN accelerator was. There were some constraints due to the reused equipment. The control system is based on Experimental Physics and Industrial Control System (EPICS). In order to reduce the cost and labor for constructing the KEKB control system, as many CAMAC modules as possible are used again. The guiding principles of the KEKB control computer system are as follows: use EPICS as the controls environment, provide a two-language system for developing application programs, use VMEbus as frontend computers as a consequence of EPICS, use standard buses, such as CAMAC, GPIB, VXIbus, ARCNET, RS-232 as field buses and use ergonomic equipment for operators and scientists. On the software side, interpretive Python and SAD languages are used for coding application programs. The purpose of the radiation safety system is to protect personnel from radiation hazards. It consists of an access control system and a beam interlock system. The access control system protects people from strong radiation inside the accelerator tunnel due to an intense beam, by controlling access to the beamline area. On the other hand, the beam interlock system prevents people from radiation exposure by interlocking the beam operation. For the convenience of accelerator operation and access control, the region covered by the safety system is divided into three major access control areas: the KEKB area, the PF-AR area, and the beam-transport (BT) area. The KEKB control system required a new timing system to match a low longitudinal acceptance due to a low-alpha machine. This timing system is based on a frequency divider/multiply technique and a digital delay technique. The RF frequency of the KEKB rings and that of the injector Linac are locked with a common divisor frequency. The common divisor frequency determines the injection timing. The RF bucket selection system is also described.

Akasaka, Nobumasa; Akiyama, Atsuyoshi; Araki, Sakae; Furukawa, Kazuro; Katoh, Tadahiko; Kawamoto, Takashi; Komada, Ichitaka; Kudo, Kikuo; Naito, Takashi; Nakamura, Tatsuro; Odagiri, Jun-ichi; Ohnishi, Yukiyoshi; Sato, Masayuki; Suetake, Masaaki; Takeda, Shigeru; Takeuchi, Yasunori; Yamamoto, Noboru; Yoshioka, Masakazu; Kikutani, Eji

2003-02-01

414

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

415

Photographic, magnetic, and interferometric measurements of current sheet canting in a pulsed electromagnetic accelerator  

E-print Network

electromagnetic accelerator T.E. Markusic£and E.Y. ChoueiriÝ Electric Propulsion and Plasma Dynamics Laboratory in a pulsed electromagnetic accelerator were measured using three different techniques: high- speed Professor, Applied Physics Group. Senior Member AIAA. ?Presented at the 37? AIAA Joint Propulsion Conference

Choueiri, Edgar

416

FABRICATION AND INSTALLATION OF SUPERCONDUCTING ACCELERATOR MODULES FOR THE ERL PROTOTYPE (ERLP) AT DARESBURY  

Microsoft Academic Search

Installation and commissioning of the superconducting energy recovery linac (ERL) prototype is under way at Daresbury Laboratory (1). ACCEL have manufactured two superconducting accelerator modules for the injector and the linac, operating at 2K with 1.3 GHz TESLA type cavities. Each module contains two cavities and is designed to provide an accelerating voltage of 25 MV in cw mode. This

Stefan Bauer; Michael Pekeler; Hanspeter Vogel; Robert Bate; Carl David Beard; Douglas M. Dykes; Peter McIntosh; Brian Todd

417

A Plasma Propulsion Concept Based on Direct Ion Acceleration with Beating Electrostatic Waves  

E-print Network

A Plasma Propulsion Concept Based on Direct Ion Acceleration with Beating Electrostatic Waves B is described. It is expected that the direct ion acceleration would yield a propulsive performance. Jorns and E.Y. Choueiri Electric Propulsion and Plasma Dynamics Laboratory, Princeton University

Choueiri, Edgar

418

Dielectric Wakefield Accelerating Structure as a Source of Terahertz Coherent Cerenkov Radiation  

Microsoft Academic Search

We discuss future experimental work proposed to study the performance of a cylindrical dielectric wakefield accelerating structure as a coherent Cerenkov radiation source at the Neptune laboratory at UCLA. The Cerenkov wakefield acceleration experiment carried out recently by UCLA\\/SLAC\\/USC, using the ultrashort and high charge beam (Q = 3 nC, sigmaz = 20 micron) at the SLAC FFTB, demonstrated electromagnetic

A. M. Cook; J. B. Rosenzweig; M. C. Thompson; H. Badakov; G. Travish; R. Tikhoplav; O. B. Williams; R. J. England

2006-01-01

419

Design of accelerated corrosion tests for electronic components in automotive applications  

Microsoft Academic Search

Two new accelerated laboratory corrosion tests for electronic components in automotive applications have been developed, based on the use of metallic copper as a meter for corrosivity. The accelerated tests are designed so that they reproduce the same kind of corrosion effects as observed with exposure of copper in real vehicle environments. The test cycle that best simulates the corrosion

Peter Eriksson; Bo Carlsson; I. O. Wallinder

2001-01-01

420

Workshop on acceleration of polarized protons: summary report  

SciTech Connect

The workshop sessions concentrated on polarized protons in circular accelerators and storage rings. Topics such as polarized electrons were discussed only when the subject was relevant to proton phenomena. Of major interest was the possible applicability of the new idea of spin matching for crossing depolarizing resonances. On the experimental side, some remarkable new data were presented by the SATURNE II Group. They have successfully crossed both intrinsic and imperfection depolarizing resonances by the spin flip method with minimal depolarization-the first group to do so. They also obtained some results which apparently cannot be explained with our present understanding of spin phenomena. The workshop concluded that more experimental measurements are needed to understand the physics and that such studies would be very important for the future acceleration of polarized protons at KEK and the AGS. The workshop included status reports from the four laboratories which have programs of polarized particle acceleration--or approved projects to accelerate polarized protons.

Lee, Y.Y.; Terwilliger, K.M.

1982-01-01

421

A plasma wakefield acceleration experiment using CLARA beam  

NASA Astrophysics Data System (ADS)

We propose a Plasma Accelerator Research Station (PARS) based at proposed FEL test facility CLARA (Compact Linear Accelerator for Research and Applications) at Daresbury Laboratory. The idea is to use the relativistic electron beam from CLARA, to investigate some key issues in electron beam transport and in electron beam driven plasma wakefield acceleration, e.g. high gradient plasma wakefield excitation driven by a relativistic electron bunch, two bunch experiment for CLARA beam energy doubling, high transformer ratio, long bunch self-modulation and some other advanced beam dynamics issues. This paper presents the feasibility studies of electron beam transport to meet the requirements for beam driven wakefield acceleration and presents the plasma wakefield simulation results based on CLARA beam parameters. Other possible experiments which can be conducted at the PARS beam line are also discussed.

Xia, G.; Angal-Kalinin, D.; Clarke, J.; Smith, J.; Cormier-Michel, E.; Jones, J.; Williams, P. H.; Mckenzie, J. W.; Militsyn, B. L.; Hanahoe, K.; Mete, O.; Aimidula, A.; Welsch, C. P.

2014-03-01

422

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

423

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

424

Status of the New Zealand tandem accelerator mass spectrometry facility  

NASA Astrophysics Data System (ADS)

A tandem accelerator mass spectrometry system is being installed at the Institute of Nuclear Sciences, and will become operational this year. Laboratories for 14C dating and low level radioactivity counting have been established here for several years, and the advent of the accelerator technique is expected to widen significantly the scope of investigations using these facilities, as well as open up new research possibilities. Oceanographic and atmospheric studies in particular are seen as fields where accelerator mass spectrometry can be fruitfully employed. The system being developed is similar to that at Zrich, and is based on a type EN tandem Van de Graaff, with magnetic and electrostatic beam analysis, and sequential acceleration of isotopes under computer control. Techniques have been developed for the conversion of carbonaceous material to graphite, for 14C dating, and the extraction of beryllium from sediments for 10Be measurements.

Sparks, R. J.; Wallace, G.; Bartle, C. M.; Coote, G. E.; Ditchburn, R. G.; Lowe, D. C.; McCabe, W. J.; Pohl, K. P.

1984-11-01

425

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

426

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

427

Breeding nuclear fuels with accelerators replacement for breeder reactors  

NASA Astrophysics Data System (ADS)

High-current, high-energy linear accelerators are potential competitors to breeder reactors and fusion devices for the production of fissile fuel. Accelerator breeder studies, conducted at Chalk River (Canada) and Brookhaven National Laboratory during the last decade, indicate that the technology is available and system's costs competitive with that of the LMFBR and Fusion-Hybrid systems. This paper addresses the technical issues to be faced in an accelerator specifically designed for commercial operation of this kind, the neutronics and engineering feasibility of target systems, and related fuel-cycle cost/benefit analysis. A nearly optimized accelerator breeder concept consisting of a 1.5 GeV, 300 mA linear accelerator, and of a H 2O-cooled, U-metal target (or thorium) has been designed and costed. Accelerator efficiency, beam-to-plug, is estimated at 50% and target power generation efficiency, beam-to-thermal output, at about 600% (U-metal case). Fuel costs produced by the facility are practically entirely driven by capital investment costs. This is also true for any competing system. On the basis, the accelerator breeder is economically competitive with the LMFBR while offering real advantages in terms of safety, fuel cycle flexibility, and resource independence.

Grand, P.; Takahashi, H.

1985-05-01

428

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

429

Venting force contributions - quasi-steady acceleration on STS-50  

NASA Astrophysics Data System (ADS)

Measurements of the quasi-steady acceleration environment on Columbia during STS-50 (the First United States Microgravity Laboratory (USML-1)) by the Orbital Acceleration Research Experimental (OARE) and the Passive Accelerometer System (PAS) differ in magnitude from those predicted from a numerical model of the environment. Known contributions to the orbiter quasi-steady acceleration environment from venting forces are investigated. The Flash Evaporator System (FES) vents steam through two opposing nozzles on either side of the aft orbiter. On USML-1, none FES cycles (14th on, 14h off) produced linear accelerations of about g(sub x) = -1.2 x 10(exp 7) g, g(sub y) = 0, g(sub z) = 7.6 dot 10(exp 8) g, relative to the orbiter body coordinate system. FES cycles are evident in recorded accelerometer data. Additional accelerations arise due to venting of waste and potable water through a vent on the orbiter's port side. On USML-1, four 1 h long waste water dumps produced linear accelerations of approximately g(sub y) = 3.8 x 10(exp 7) g. Orbiter motion caused by port side water dumps is corrected by Reaction Control System (RCS) engine firings. Transient accelerations related to such thruster activity are manifested in recorded accelerometer data.

Rogers, M. J. B.; Matisak, B. P.; Alexander, J. I. D.

1994-02-01

430

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

431

Accelerating Commercial Remote Sensing  

NASA Technical Reports Server (NTRS)

Through the Visiting Investigator Program (VIP) at Stennis Space Center, Community Coffee was able to use satellites to forecast coffee crops in Guatemala. Using satellite imagery, the company can produce detailed maps that separate coffee cropland from wild vegetation and show information on the health of specific crops. The data can control coffee prices and eventually may be used to optimize application of fertilizers, pesticides and irrigation. This would result in maximal crop yields, minimal pollution and lower production costs. VIP is a mechanism involving NASA funding designed to accelerate the growth of commercial remote sensing by promoting general awareness and basic training in the technology.

1995-01-01

432

Accelerated Innovation Pilot  

NASA Technical Reports Server (NTRS)

Opportunities: I. Engage NASA team (examples) a) Research and technology calls . provide suggestions to AES, HRP, OCT. b) Use NASA@Work to solicit other ideas; (possibly before R+D calls). II. Stimulate collaboration (examples) a) NHHPC. b) Wharton Mack Center for Technological Innovation (Feb 2013). c) International ] DLR ] :envihab (July 2013). d) Accelerated research models . NSF, Myelin Repair Foundation. III. Engage public Prizes (open platform: InnoCentive, yet2.com, NTL; Rice Business Plan, etc.) IV. Use same methods to engage STEM.

Davis, Jeffrey

2012-01-01

433

Circus Physics: Centripetal Acceleration  

NSDL National Science Digital Library

This video-based resource examines centripetal force through the motion of circus animals running around a ring. Objects moving in a circle (even at constant speed) are experiencing acceleration because the center-seeking force causes a change in velocity. The video can serve to help students understand that an unbalanced force can change the direction of the velocity vector but not its magnitude. It includes tips on how to incorporate the video into instruction, discussion questions, and accompanying classroom activities. This resource was developed in conjunction with the PBS series Circus. See Related Materials for a link to the full set of 8 Circus Physics video-based lessons.

2013-11-19

434

The LUE-200 accelerator at the IREN facility: Current status and development  

NASA Astrophysics Data System (ADS)

The general scheme and current status of an electron linear accelerator with an S-band travelling wave ( f = 2856 MHz) accelerating structurea driver for a pulsed neutron source (the Intense Resonance Neutron source (IREN)) at the Frank Laboratory of Neutron Physics of the Joint Institute for Nuclear Researchare presented. The parameters of the accelerating system and the measured parameters of the electron beampulse-beam current, duration of the current pulse, repetition rate, electron-energy spectrum, and loading characteristics of the accelerating structureare given. The beginning of the implementation of the project of the second stage of the IREN facility, which forms the basis for the development of the accelerator aimed at increasing its beam power, is reported. Technical solutions underlying the modernization of the accelerator's electrophysical systems are discussed: accelerating system, RF power supplies, and modulators.

Boettcher, Ju.; Golubkov, E. A.; Egorov, V. A.; Zaytseva, Yu. K.; Zamrij, V. N.; Kayukov, A. S.; Kobets, V. V.; Korokin, A. Zh.; Minashkin, V. F.; Pyataev, V. G.; Repkin, A. N.; Skrypnik, A. V.; Sumbaev, A. P.; Udovichenko, K. V.; Shabratov, V. G.; Schvets, V. A.; Shvetsov, V. N.; Pavlov, V. M.

2014-09-01

435

Auditory localization under sustained +Gz acceleration.  

PubMed

The ability to localize a virtual sound source in the horizontal plane was evaluated under varying levels of sustained (+Gz) acceleration. Participants were required to judge the locations of spatialized noise bursts in the horizontal plane (elevation 0 degrees) during exposure to 1.0, 1.5, 2.5, 4.0, 5.5, and 7.0 +Gz. The experiment was conducted at the U.S. Air Force Research Laboratory's Dynamic Environment Simulator, a three-axis centrifuge. No significant increases in localization error were found between 1.0 and 5.5 +Gz; however, a significant increase did occur at the 7.0 +Gz level. In addition, the percentage of front/back confusions did not vary as a function of +Gz level. Collectively, these results indicate that the ability to localize virtual sound sources is well maintained at various levels of sustained acceleration. Actual or potential applications include the incorporation of spatial audio displays into the human-computer interface for vehicles that are operated in acceleration environments. PMID:11592670

Nelson, W T; Bolia, R S; Tripp, L D

2001-01-01

436

Radiochemical Radiochemical Processing Laboratory  

E-print Network

is a critical facility at the Pacific Northwest National Laboratory, supporting environmental, nuclear, national and environmental remediation researching, testing, and validating process flowsheets designing, installingRadiochemical Processing Laboratory #12;Radiochemical Processing Laboratory Housed within the U

437

Accelerated partial breast irradiation.  

PubMed

Local therapies to treat newly diagnosed breast cancer include a lumpectomy with radiation therapy or a mastectomy. The 20-year data from studies about the safety and efficacy of lumpectomy with full-breast radiation therapy support the safety of this regimen and its role to decrease the risk of ipsilateral recurrence and increase long-term survivorship of women with breast cancer. Accelerated partial breast irradiation (APBI) provides radiation therapy to the tumor bed but spares the remaining breast tissue. APBI accelerates the time required to complete the therapy regimen, with a range of one intraoperative session to five consecutive days compared to five to seven weeks. Several techniques exist to administer APBI, including the insertion of a balloon into the lumpectomy space. Of interest is the widespread use of APBI in community and academic settings that has preceded outcomes of large, randomized clinical trials. Because of selection bias in a number of small, single-institution, nonrandomized studies, published data are of limited value to ensure APBI as a standard of care. PMID:25253109

Bauer, Elfrida; Lester, Joanne L

2014-10-01

438

Short bunch research at Brookhaven National Laboratory  

NASA Astrophysics Data System (ADS)

Research into the production and utilization of short electron bunches at Brookhaven National Laboratory is underway at the Source Development Laboratory (SDL) and Accelerator Test Facility (ATF). Projects planned for the SDL facility include a 210 MeV electron linac with a dipole chicane that is designed to produce 100 ?m long bunches and a compact electron storage ring that will use superconducting RF to produce sub-millimeter bunches. The ATF has a 30-70 MeV linac that will serve as the injector for laser accelerators that will bunch the beam into to micron-length bunches. Coherent transition and synchrotron radiation from the short bunches will be used for beam diagnostics and infrared experiments.

Blum, Eric B.

1996-04-01

439

Experimental demonstration of a 120-mm ram accelerator  

NASA Astrophysics Data System (ADS)

Ram acceleration is an emerging propulsion technology in which a projectile similar in shape to the centerbody of a ramjet aircraft engine is injected at high speed into a tube filled with a combustible gaseous mixture. As the projectile moves into the tube, under supersonic conditions, shocks occur on and around the projectile. If the gases are then ignited either by the energy in the shock system or an external mechanism, the combustion around or behind the projectile can be self-sustaining. The net effect is to generate a localized high pressure region around and/or behind the projectile which produces acceleration. Work at the University of Washington, Seattle, has demonstrated velocities in excess of 2.6 km/s in 38-mm caliber, while theory predicts velocities above 7 km/s may be obtainable. A program was initiated at the Weapons Technology Directorate of the US Army Research Laboratory (formerly Ballistic Research Laboratory) to examine the scaling potential of ram acceleration for use as a high velocity, high mass, (i.e., high kinetic energy) launcher. Data from initial gas mixing tests and first firings through a 120-mm bore diameter ram accelerator with both inert and live fuel gases are presented. Initial comparisons with ram accelerators of smaller scale are made. Discussions of scaling parameters as currently understood will be presented.

Kruczynski, David L.

1992-10-01

440

Accelerator Technology Program. Progress report, January-June 1980  

SciTech Connect

The activities of Los Alamos Scientific Laboratory's (LASL) Accelerator Technology (AT) Division during the first six months of calendar 1980 are discussed. This report is organized around major projects of the Division, reflecting a wide variety of applications and sponsors. The first section summarizes progress on the Proton Storage Ring to be located between LAMPF and the LASL Pulsed Neutron Research facility, followed by a section on the gyrocon, a new type of high-power, high-efficiency radio-frequency (rf) amplifier. The third section discusses the racetrack microtron being developed jointly by AT Division and the National Bureau of Standards; the fourth section concerns the free-electron studies. The fifth section covers the radio-frequency quadrupole linear accelerator, a new concept for the acceleration of low-velocity particles; this section is followed by a section discussing heavy ion fusion accelerator development. The next section reports activities in the Fusion Materials Irradiation Test program, a collaborative effort with the Hanford Engineering Development Laboratory. The final section deals first with development of H/sup -/ ion sources and injectors, then with accelerator instrumentation and beam dynamics.

Knapp, E.A.; Jameson, R.A. (Comps.)

1980-03-01

441

Magnetic Insulation for Electrostatic Accelerators  

SciTech Connect

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

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

2011-09-26

442

Accelerator Technology for the Mankind  

E-print Network

Particle accelerators technology is one of the generic technologies which is locomotive of the development in almost all fields of science and technology. According to the U.S. Department of Energy: "Accelerators underpin every activity of the Office of Science and, increasingly, of the entire scientific enterprise. From biology to medicine, from materials to metallurgy, from elementary particles to the cosmos, accelerators provide the microscopic information that forms the basis for scientific understanding and applications. The combination of ground and satellite based observatories and particle accelerators will advance our understanding of our world, our galaxy, our universe, and ourselves." Because of this, accelerator technology should become widespread all over the world. Existing situation shows that a large portion of the world, namely the South and Mid-East, is poor on the accelerator technology. UNESCO has recognized this deficit and started SESAME project in Mid-East, namely Jordan. Turkic Acceler...

Sultansoy, S

2006-01-01

443

Particle acceleration in pulsar magnetospheres  

NASA Technical Reports Server (NTRS)

The structure of pulsar magnetospheres and the acceleration mechanism for charged particles in the magnetosphere was studied using a pulsar model which required large acceleration of the particles near the surface of the star. A theorem was developed which showed that particle acceleration cannot be expected when the angle between the magnetic field lines and the rotation axis is constant (e.g. radial field lines). If this angle is not constant, however, acceleration must occur. The more realistic model of an axisymmetric neutron star with a strong dipole magnetic field aligned with the rotation axis was investigated. In this case, acceleration occurred at large distances from the surface of the star. The magnitude of the current can be determined using the model presented. In the case of nonaxisymmetric systems, the acceleration is expected to occur nearer to the surface of the star.

Baker, K. B.

1978-01-01

444

LUNA: a Laboratory for Underground Nuclear Astrophysics  

E-print Network

It is in the nature of astrophysics that many of the processes and objects one tries to understand are physically inaccessible. Thus, it is important that those aspects that can be studied in the laboratory be rather well understood. One such aspect are the nuclear fusion reactions, which are at the heart of nuclear astrophysics. They influence sensitively the nucleosynthesis of the elements in the earliest stages of the universe and in all the objects formed thereafter, and control the associated energy generation, neutrino luminosity, and evolution of stars. We review an experimental approach for the study of nuclear fusion reactions based on an underground accelerator laboratory, named LUNA.

H. Costantini; A. Formicola; G. Imbriani; M. Junker; C. Rolfs; F. Strieder

2009-06-05

445

Modern electron accelerators for radiography  

SciTech Connect

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

Ekdahl, C. A. (Carl A.)

2001-01-01

446

Recirculating Heavy Ion Accelerator Experiment  

Microsoft Academic Search

Because of their high efficiency, high repetition rate, and relatively simple target chamber geometry, heavy-ion accelerators are attractive candidates as drivers for inertial fusion power plants. Recirculating induction accelerators have been proposed as potential lower cost alternatives to linear induction machines. The requirement of coordinated and accelerated bending introduces new challenges. A program to develop a small (2.2m radius) scaled

A. Molvik; J. J. Barnard; M. D. Cable; D. A. Callahan; V. Cianciolo; A. Friedman; D. P. Grote; G. W. Kamin; H. C. Kirbie; B. G. Logan; S. M. Lund; L. A. Nattrass; M. B. Nelson; T. C. Sangster; W. M. Sharp; C. Ward; T. J. Fessenden; D. L. Judd; H. S. Hopkins; A. G. Debeling; D. B. Longinotti

1996-01-01

447

Coherent multimoded dielectric wakefield accelerators.  

SciTech Connect

There has recently been a study of the potential uses of multimode dielectric structures for wakefield acceleration [1]. This technique is based on adjusting the wakefield modes of the structure to constructively interfere at certain delays with respect to the drive bunch, thus providing an accelerating gradient enhancement over single mode devices. In this report we examine and attempt to clarify the issues raised by this work in the light of the present state of the art in wakefield acceleration.

Power, J.

1998-07-16

448

Coherent multimoded dielectric wakefield accelerators  

SciTech Connect

There has recently been a study of the potential uses of multimode dielectric structures for wakefield acceleration. This technique is based on adjusting the wakefield modes of the structure to constructively interfere at certain delays with respect to the drive bunch, thus providing an accelerating gradient enhancement over single mode devices. In this report we examine and attempt to clarify the issues raised by this work in the light of the present state of the art in wakefield acceleration.

Power, J.; Gai, W.; Schoessow, P. [Argonne National Laboratory, High Energy Physics Division, 9700 S Cass Ave, Argonne, Illinois 60439 (United States)

1999-07-12

449

Particle acceleration in solar flares  

NASA Technical Reports Server (NTRS)

The most direct signatures of particle acceleration in flares are energetic particles detected in interplanetary space and in the Earth atmosphere, and gamma rays, neutrons, hard X-rays, and radio emissions produced by the energetic particles in the solar atmosphere. The stochastic and shock acceleration theories in flares are reviewed and the implications of observations on particle energy spectra, particle confinement and escape, multiple acceleration phases, particle anistropies, and solar atmospheric abundances are discussed.

Ramaty, R.; Forman, M. A.

1987-01-01

450

Cast dielectric composite linear accelerator  

DOEpatents

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

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

2009-11-10

451

Basic concepts in plasma accelerators.  

PubMed

In this article, we present the underlying physics and the present status of high gradient and high-energy plasma accelerators. With the development of compact short pulse high-brightness lasers and electron and positron beams, new areas of studies for laser/particle beam-matter interactions is opening up. A number of methods are being pursued vigorously to achieve ultra-high-acceleration gradients. These include the plasma beat wave accelerator (PBWA) mechanism which uses conventional long pulse ( approximately 100 ps) modest intensity lasers (I approximately 10(14)-10(16) W cm(-2)), the laser wakefield accelerator (LWFA) which uses the new breed of compact high-brightness lasers (<1 ps) and intensities >10(18) W cm(-2), self-modulated laser wakefield accelerator (SMLWFA) concept which combines elements of stimulated Raman forward scattering (SRFS) and electron acceleration by nonlinear plasma waves excited by relativistic electron and positron bunches the plasma wakefield accelerator. In the ultra-high intensity regime, laser/particle beam-plasma interactions are highly nonlinear and relativistic, leading to new phenomenon such as the plasma wakefield excitation for particle acceleration, relativistic self-focusing and guiding of laser beams, high-harmonic generation, acceleration of electrons, positrons, protons and photons. Fields greater than 1 GV cm(-1) have been generated with monoenergetic particle beams accelerated to about 100 MeV in millimetre distances recorded. Plasma wakefields driven by both electron and positron beams at the Stanford linear accelerator centre (SLAC) facility have accelerated the tail of the beams. PMID:16483948

Bingham, Robert

2006-03-15

452

University of Washington, Nuclear Physics Laboratory annual report, 1995  

SciTech Connect

The Nuclear Physics Laboratory of the University of Washington supports a broad program of experimental physics research. The current program includes in-house research using the local tandem Van de Graff and superconducting linac accelerators and non-accelerator research in double beta decay and gravitation as well as user-mode research at large accelerator and reactor facilities around the world. This book is divided into the following areas: nuclear astrophysics; neutrino physics; nucleus-nucleus reactions; fundamental symmetries and weak interactions; accelerator mass spectrometry; atomic and molecular clusters; ultra-relativistic heavy ion collisions; external users; electronics, computing, and detector infrastructure; Van de Graff, superconducting booster and ion sources; nuclear physics laboratory personnel; degrees granted for 1994--1995; and list of publications from 1994--1995.

NONE

1995-04-01

453

Acceleration and the fifth dimension  

E-print Network

A correlation between accelerated motion and a noncompact 5th dimension is proposed. The curvature invariants and the stress energy tensor in the bulk depend only on the 5th dimension $w$ and vanish asymptotically while the proper acceleration of a static observer is proportional to $1/w$. The brane (located at $w = w_{0}$) metric is conformally flat (of AdS type) with $\\Lambda = -3/w_{0}^{2}$ and the invariant acceleration $a = \\sqrt{a^{b}a_{b}} = 1/w_{0}$. Therefore, we assume that a hyperbolic observer with the rest-system acceleration $a$ is embedded in the 5th dimension at $w_{0} = 1/a$.

Culetu, Hristu

2014-01-01

454

Accelerators for research and applications  

SciTech Connect

The newest particle accelerators are almost always built for extending the frontiers of research, at the cutting edge of science and technology. Once these machines are operating and these technologies mature, new applications are always found, many of which touch our lives in profound ways. The evolution of accelerator technologies will be discussed, with descriptions of accelerator types and characteristics. The wide range of applications of accelerators will be discussed, in fields such as nuclear science, medicine, astrophysics and space-sciences, power generation, airport security, materials processing and microcircuit fabrication. 13 figs.

Alonso, J.R.

1990-06-01

455

Pulsed Plasma Accelerator Modeling  

NASA Technical Reports Server (NTRS)

This report presents the main results of the modeling task of the PPA project. The objective of this task is to make major progress towards developing a new computational tool with new capabilities for simulating cylindrically symmetric 2.5 dimensional (2.5 D) PPA's. This tool may be used for designing, optimizing, and understanding the operation of PPA s and other pulsed power devices. The foundation for this task is the 2-D, cylindrically symmetric, magnetohydrodynamic (MHD) code PCAPPS (Princeton Code for Advanced Plasma Propulsion Simulation). PCAPPS was originally developed by Sankaran (2001, 2005) to model Lithium Lorentz Force Accelerators (LLFA's), which are electrode based devices, and are typically operated in continuous magnetic field to the model, and implementing a first principles, self-consistent algorithm to couple the plasma and power circuit that drives the plasma dynamics.

Goodman, M.; Kazeminezhad, F.; Owens, T.

2009-01-01

456

Pulsed electromagnetic acceleration  

NASA Technical Reports Server (NTRS)

Direct measurements of the power deposited in the anode of a multimegawatt MPD accelerator using thermocouples attached to a thin shell anode reveal a dramatic decrease in the fractional anode power from 50% at 200 KW input power to less than 10% at 20 MW power. The corresponding local power flux peak at a value of 10,000 W/sq cm at the lip of the anode exhaust orifice, a distribution traced to a corresponding peak in the local current density at the anode. A comparison of voltage-current characteristics and spectral photographs of the MPD discharge using quartz, boron nitride and plexiglas insulators with various mass injection configurations led to the identification of different voltage modes and regions of ablation free operation. The technique of piezoelectric impact pressure measurement in the MPD exhaust flow was refined to account for the effects due to probe yaw angle.

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

1973-01-01

457

Accelerating Spectrum Sharing Technologies  

SciTech Connect

Spectrum sharing potentially holds the promise of solving the emerging spectrum crisis. However, technology innovators face the conundrum of developing spectrum sharing technologies without the ability to experiment and test with real incumbent systems. Interference with operational incumbents can prevent critical services, and the cost of deploying and operating an incumbent system can be prohibitive. Thus, the lack of incumbent systems and frequency authorization for technology incubation and demonstration has stymied spectrum sharing research. To this end, industry, academia, and regulators all require a test facility for validating hypotheses and demonstrating functionality without affecting operational incumbent systems. This article proposes a four-phase program supported by our spectrum accountability architecture. We propose that our comprehensive experimentation and testing approach for technology incubation and demonstration will accelerate the development of spectrum sharing technologies.

Juan D. Deaton; Lynda L. Brighton; Rangam Subramanian; Hussein Moradi; Jose Loera

2013-09-01

458

Network acceleration techniques  

NASA Technical Reports Server (NTRS)

Splintered offloading techniques with receive batch processing are described for network acceleration. Such techniques offload specific functionality to a NIC while maintaining the bulk of the protocol processing in the host operating system ("OS"). The resulting protocol implementation allows the application to bypass the protocol processing of the received data. Such can be accomplished this by moving data from the NIC directly to the application through direct memory access ("DMA") and batch processing the receive headers in the host OS when the host OS is interrupted to perform other work. Batch processing receive headers allows the data path to be separated from the control path. Unlike operating system bypass, however, the operating system still fully manages the network resource and has relevant feedback about traffic and flows. Embodiments of the present disclosure can therefore address the challenges of networks with extreme bandwidth delay products (BWDP).

Crowley, Patricia (Inventor); Awrach, James Michael (Inventor); Maccabe, Arthur Barney (Inventor)

2012-01-01

459

Accelerator mass spectrometry  

SciTech Connect

Accelerator mass spectroscopy (AMS) can be used for efficient detection of long-lived isotopes at part-per-quadrillion sensitivities with good precision. In this article we present an overview of AMS and its recent use in archaeology, geochemistry and biomolecular tracing. All AMS systems use cesium sputter ion sources to produce negative ions from a small button of a solid sample containing the element of interest, such as graphite, metal halide, or metal oxide, often mixed with a metal powder as binder and thermal conductor. Experience shows that both natural and biomedical samples are compatible in a single AMS system, but few other AMS sites make routine {sup 14}C measurements for both dating and tracing. AMS is, in one sense, just `a very sensitive decay counter`, but if AMS sensitivity is creatively coupled to analytical chemistry of certain isotopes, whole new areas of geosciences, archaeology, and life sciences can be explored. 29 refs., 2 figs., 1 tab.

Vogel, J.S.; Turteltaub, K.W.; Finkel, R. [Lawrence Livermore National Lab., CA (United States); Nelson, D.E.

1995-06-01

460

Flexible low-cost automated scaled highway (FLASH) laboratory for studies on automated highway systems  

Microsoft Academic Search

This paper addresses the development of a flexible low-cost automated scale highway (FLASH) laboratory which is intended to serve as a catalyst for accelerating the development of many intelligent vehicle highway system (IVHS) concepts. It also highlights the significance of the laboratory for the research, evaluation, and testing of automated highway system (AHS) configurations, architectures, designs and technologies. This laboratory,

Pushkin Kachroo; Kaan Ozbay; Robert G. Leonard; C. Unsal

1995-01-01

461

Accelerators and Superconductivity: A Marriage of Convenience. Second John Adams Memorial Lecture  

NASA Astrophysics Data System (ADS)

This lecture deals with the relationship between accelerator technology in high-energy-physics laboratories and the development of superconductors. It concentrates on synchrotron magnets, showing how their special requirements have brought about significant advances in the technology, particularly the development of filamentary superconducting composites. Such developments have made large superconducting accelerators an actuality: the Tevatron in routine operation, the Hadron Electron Ring Accelerator (HERA) under construction, and the Superconducting Super Collider (SSC) and Large Hadron Collider (LHC) at the conceptual design stage. Other applications of superconductivity have also been facilitated - for example medical imaging and small accelerators for industrial and medical use.

Wilson, Martin

1987-06-01

462

Activation caused by proton beam losses in Accelerator Production of Tritium LINAC  

SciTech Connect

A variety of accelerator designs are being considered for the Accelerator Production of Tritium (APT) project at Alamos National Laboratory. Because activation of the structural components of the accelerator is considered a major radiation protection issue, we have developed a computational methodology to estimate quantitatively radionuclide inventories and gamma dose rates resulting from accelerator operation. The work presented here illustrates the use of our computational methodology by focusing on the 20 and 100 MeV sections of the Bridge-Coupled Drift Tube LINAC (BCDTL), and the 100 and 1000 MeV sections of the Coupled Cavity LINAC (CCL).

Beard, C.A.; Eaton, S.L.; Daemen, L.L.; Waters, L.S.; Wilson, W.B.

1996-03-01

463

Development of a 20-MeV Dielectric-Loaded Accelerator Test Facility  

SciTech Connect

This paper describes a joint project by the Naval Research Laboratory (NRL) and Argonne National Laboratory (ANL), in collaboration with the Stanford Linear Accelerator Center (SLAC), to develop a dielectric-loaded accelerator (DLA) test facility powered by a high-power 11.424-GHz magnicon amplifier. The magnicon can presently produce 25 MW of output power in a 250-ns pulse at 10 Hz, and efforts are in progress to increase this to 50 MW. The facility will include a 5 MeV electron inector being developed by the Accelerator Laboratory of Tsinghua University in Beijing, China. The DLA test structures are being developed by ANL, and some have undergone testing at NRL at gradients up to {approx} 8 MV/m. SLAC is developing a means to combine the two magnicon output arms, and to drive an injector and accelerator with separate control of the power ratio and relative phase. RWBruce Associates, Inc., working with NRl, is developing a means to join short ceramic sections into a continuous accelerator tube by ceramic brazing using an intense millimeter-wave beam. The installation and testing of the first dielectric-loaded test accelerator, including injector, DLA structure, and spectrometer, should take place within the next year. The facility will be used for testing DLA structures using a variety of materials and configurations, and also for testing other X-band accelerator concepts. The initial goal is to produce a compact 20 MeV dielectric-loaded test accelerator.

Gold, S.H.; Kinkead, A.K.; Gai, W.; Power, J.G.; Konecny, R.; Jing, C.G.; Tantawi, S.G.; Nantista, C.D.; Hu, Y.; Chen, H.; Tang, C.; Lin, Y.; Bruce, R.W.; Bruce, R.L.; Fliflet, A.W.; Lewis, D.; /Naval Research Lab, Wash., D.C. /LET Corp., Washington /Argonne /SLAC /Tsinghua U., Beijing

2005-06-22

464

Development of a residual acceleration data reduction and dissemination plan  

NASA Technical Reports Server (NTRS)

A major obstacle in evaluating the residual acceleration environment in an orbiting space laboratory is the amount of data collected during a given mission: gigabytes of data will be available as SAMS units begin to fly regularly. Investigators taking advantage of the reduced gravity conditions of space should not be overwhelmed by the accelerometer data which describe these conditions. We are therefore developing a data reduction and analysis plan that will allow principal investigators of low-g experiments to create experiment-specific residual acceleration data bases for post-flight analysis. The basic aspects of the plan can also be used to characterize the acceleration environment of earth orbiting laboratories. Our development of the reduction plan is based on the following program of research: the identification of experiment sensitivities by order of magnitude estimates and numerical modelling; evaluation of various signal processing techniques appropriate for the reduction, supplementation, and dissemination of residual acceleration data; and testing and implementation of the plan on existing acceleration data bases. The orientation of the residual acceleration vector with respect to some set of coordinate axes is important for experiments with known directional sensitivity. Orientation information can be obtained from the evaluation of direction cosines. Fourier analysis is commonly used to transform time history data into the frequency domain. Common spectral representations are the amplitude spectrum which gives the average of the components of the time series at each frequency and the power spectral density which indicates the power or energy present in the series per unit frequency interval. The data reduction and analysis scheme developed involves a two tiered structure to: (1) identify experiment characteristics and mission events that can be used to limit the amount of accelerator data an investigator should be interested in; and (2) process the data in a way that will be meaningful to the experiment objectives. A general outline of the plan is given.

Rogers, Melissa J. B.

1992-01-01

465

THE 13TH ADVANCED ACCELERATOR CONCEPTS WORKSHOP (AAC'8)  

SciTech Connect

The Thirteenth Workshop on Advanced Accelerator Concepts (AAC) was held from July 27 to August 2, 2008 at the Chaminade Conference Center in Santa Cruz, California, USA, organized by the Lawrence Berkeley National Laboratory and the University of California at Berkeley. There were unprecedented levels of interest in the 2008 AAC Workshop, and participation was by invitation, with 215 workshop attendees, including 58 students. Reflecting the world-wide growth of the advanced accelerator community, there was significant international participation, with participants from twelve countries attending.

Leemans, Wim [UC Berkeley] [UC Berkeley; Schroder, Carl B.; Esarey, Eric

2008-07-15

466

Overview of Laser-Plasma Acceleration Programs in Asia  

SciTech Connect

With many high power laser systems ranging from a few TW to multi-100 TW installed in some laboratories in Asia, significant progress on laser-driven wakefield acceleration of electrons has been achieved. Generation of quasi-monoenergetic electron beams from tens of MeV to nearly GeV has been demonstrated. Several programs for ion/proton acceleration aiming at potential medical applications are running or planned based upon their significant theoretical and numerical findings. There are quite a few collaborations existing among Asian research groups.

Sheng, Z. M.; Zhang, J. [Department of Physics, Shanghai Jiao Tong University, Shanghai 200240 (China); Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

2010-11-04

467

Accelerator Technology Program. Status report, October 1983-March 1984  

SciTech Connect

This report covers major projects in the Accelerator Technology (AT) Division of the Los Alamos National Laboratory. The first sections highlight activities related to beam dynamics, inertial fusion, structure development, the racetrack microtron, and the CERN high-energy physics experiment NA-12. Discussed next is the Fusion Materials Irradiation Test Facility, followed by a summary of progress on the Proton Storage Ring and activities of the Theory and Simulation Group. The report concludes with a discussion of the H- accelerator program and a listing of papers published by AT-Division personnel during this reporting period.

Jameson, R.A. (comp.)

1985-01-01

468

A proton medical accelerator by the SBIR route: An example of technology transfer  

SciTech Connect

Medical facilities for radiation treatment of cancer with protons have been established in many laboratories throughout the world. Essentially all of these have been designed as physics facilities, however, because of the requirement for protons up to 250 MeV. Most of the experience in this branch of accelerator technology lies in the national laboratories and a few large universities. A major issue is the transfer of this technology to the commercial sector to provide hospitals with simple, reliable, and relatively inexpensive accelerators for this application. The author has chosen the SBIR route to accomplish this goal. ACCTEK Associates have received grants from the National Cancer Institute for development of the medical accelerator and beam delivery systems. Considerable encouragement and help has been received from Argonne National Laboratory and the Department of Energy. The experiences to date and the pros and cons on this approach to commercializing medical accelerators are described. 4 refs., 1 fig.

Martin, R.L.

1988-01-01

469

Status of the inverse Compton backscattering source at Daresbury Laboratory  

Microsoft Academic Search

Inverse Compton scattering is a promising method to implement a high-brightness, ultra-short, energy tuneable X-ray source at accelerator facilities and at laser facilities using laser wake-field acceleration. We have developed an inverse Compton X-ray source driven by the multi-10-TW laser installed at Daresbury Laboratory. Polarized X-ray pulses will be generated through the interaction of laser pulses with electron bunches delivered

G. Priebe; D. Filippetto; O. Williams; Y. M. Saveliev; L. B. Jones; D. Laundy; M. A. MacDonald; G. P. Diakun; P. J. Phillips; S. P. Jamison; K. M. Spohr; S. Ter-Avetisyan; G. J. Hirst; J. Collier; E. A. Seddon; S. L. Smith

2009-01-01

470

Accelerating Venture Creation and Building on Mutual Strengths in Experimental Business Labs  

ERIC Educational Resources Information Center

This paper articulates the opportunity of using an experimental business laboratory approach as a means of accelerating the creation, incubation and testing of new venture ideas. Such a strategy leads to the establishment of a micro-ecosystem of aspiring entrepreneurs and others in a business laboratory environment. The goal is to create a mini

Curley, Martin G.; Formica, Piero

2010-01-01

471

A proton medical accelerator by the SBIR route - an example of technology transfer  

Microsoft Academic Search

Medical facilities for radiation treatment of cancer with protons have been established in many laboratories throughout the world. Essentially all of these have been designed as physics facilities, however, because of the requirement for protons up to 250 MeV. Most of the experience in this branch of accelerator technology lies in the national laboratories and a few large universities. A

R. L. Martin

1989-01-01

472

Nb3Sn accelerator magnet development around the world  

SciTech Connect

During the past 30 years superconducting magnet systems have enabled accelerators to achieve energies and luminosities that would have been impractical if not impossible with resistive magnets. By far, NbTi has been the preferred conductor for this application because of its ductility and insensitivity of Jc to mechanical strain. This is despite the fact that Nb{sub 3}Sn has a more favorable Jc vs. B dependence and can operate at much higher temperatures. Unfortunately, NbTi conductor is reaching the limit of it usefulness for high field applications. Despite incremental increases in Jc and operation at superfluid temperatures, magnets are limited to approximately a 10 T field. Improvements in conductor performance combined with future requirements for accelerator magnets to have bore fields greater than 10 T or operate in areas of large beam-induced heat loads now make Nb{sub 3}Sn look attractive. Thus, laboratories in several countries are actively engaged in programs to develop Nb{sub 3}Sn accelerator magnets for future accelerator applications. A summary of this important research activity is presented along with a brief history of Nb{sub 3}Sn accelerator magnet development and a discussion of requirements for future accelerator magnets.

Michael J. Lamm

2003-06-23

473

The LILIA (laser induced light ions acceleration) experiment at LNF  

NASA Astrophysics Data System (ADS)

Laser-matter interaction at relativistic intensities opens up new research fields in the particle acceleration and related secondary sources, with immediate applications in medical diagnostics, biophysics, material science, inertial confinement fusion, up to laboratory astrophysics. In particular laser-driven ion acceleration is very promising for hadron therapy once the ion energy will attain a few hundred MeV. The limited value of the energy up to now obtained for the accelerated ions is the drawback of such innovative technique to the real applications. LILIA (laser induced light ions acceleration) is an experiment now running at LNF (Frascati) with the goal of producing a real proton beam able to be driven for significant distances (50-75 cm) away from the interaction point and which will act as a source for further accelerating structure. In this paper the description of the experimental setup, the preliminary results of solid target irradiation and start to end simulation for a post-accelerated beam up to 60 MeV are given.

Agosteo, S.; Anania, M. P.; Caresana, M.; Cirrone, G. A. P.; De Martinis, C.; Delle Side, D.; Fazzi, A.; Gatti, G.; Giove, D.; Giulietti, D.; Gizzi, L. A.; Labate, L.; Londrillo, P.; Maggiore, M.; Nassisi, V.; Sinigardi, S.; Tramontana, A.; Schillaci, F.; Scuderi, V.; Turchetti, G.; Varoli, V.; Velardi, L.

2014-07-01

474

Kr II laser-induced fluorescence for measuring plasma acceleration.  

PubMed

We present the application of laser-induced fluorescence of singly ionized krypton as a diagnostic technique for quantifying the electrostatic acceleration within the discharge of a laboratory cross-field plasma accelerator also known as a Hall effect thruster, which has heritage as spacecraft propulsion. The 728.98 nm Kr II transition from the metastable 5d(4)D(7/2) to the 5p(4)P(5/2)(?) state was used for the measurement of laser-induced fluorescence within the plasma discharge. From these measurements, it is possible to measure velocity as krypton ions are accelerated from near rest to approximately 21 km/s (190 eV). Ion temperature and the ion velocity distributions may also be extracted from the fluorescence data since available hyperfine splitting data allow for the Kr II 5d(4)D(7/2)-5p(4)P(5/2)(?) transition lineshape to be modeled. From the analysis, the fluorescence lineshape appears to be a reasonable estimate for the relatively broad ion velocity distributions. However, due to an apparent overlap of the ion creation and acceleration regions within the discharge, the distributed velocity distributions increase ion temperature determination uncertainty significantly. Using the most probable ion velocity as a representative, or characteristic, measure of the ion acceleration, overall propellant energy deposition, and effective electric fields may be calculated. With this diagnostic technique, it is possible to nonintrusively characterize the ion acceleration both within the discharge and in the plume. PMID:23126755

Hargus, W A; Azarnia, G M; Nakles, M R

2012-10-01

475

Mechanical features of the ATS RFQ linear accelerator  

SciTech Connect

A radio-frequency quadrupole (RFQ) linear accelerator has been constructed and placed in operation on the Los Alamos National Laboratory accelerator test stand (ATS). This accelerator uses an evacuated rf manifold to distribute rf excitation from the 425-MHz rf power supply to the slot-coupled, RFQ vane-cavity, resonator assembly. The RFQ vanes are supported on commercially available copper-plated, linear, resilient C-seals to provide a high-conductivity rf contact that permits aligning and positioning the vanes during tuning, and demounting the vanes for evaluation and modification as necessary. All rf structures are fabricated from stress-relieved, bright-acid copper-plated carbon steel. Measurements made on the accelerator as assembled have demonstrated >8000 vane-cavity Q at the quadrupole's approx. 423.400-MHz accelerating-mode frequency. Operating manifold vacuum of 3 to 6 x 10/sup -8/ torr has been observed after rf conditioning; conditioning required 150 h for stable high-power rf operation. Experience to date has indicated the desirability of modifying the vane rf-contact seat configuration to improve assembly and alignment procedures, improving vane-machining processes to increase vane straightness, installing periodic vane-shorting rings to minimize the effect of dipole modes in the quadrupole accelerating structure,and modifying the waveguide-coupling slot in the manifold to improve forward rf power flow.

Wilson, N.G.; Hayward, T.D.; Lind, G.W.

1983-01-01

476

The BNL Accelerator Test Facility and experimental program  

SciTech Connect

The Accelerator Test Facility (ATF) at BNL is a users` facility for experiments in Accelerator and Beam Physics. The ATF provides high brightness electron beams and high-power laser pulses synchronized to the electron beam, suitable for studies of new methods of high-gradient acceleration and state-of-the-art Free-Electron Lasers. The electrons are produced by a laser photocathode rf gun and accelerated to 50 MeV by two traveling wave accelerator sections. The lasers include a 10 mJ, 10 ps ND:YAG laser and a 500 mJ, 10 to 100 ps C0{sub 2} laser. A number of users from National Laboratories, universities and industry take part in experiments at the ATF. The experimental program includes various laser acceleration schemes, Free-Electron Laser experiments and a program on the development of high-brightness electron beams. The ATF`s experimental program commenced in early 1991 at an energy of about 4 MeV. The full program, with 50 MeV and the high-power laser will begin operation this year.

Ben-Zvi, I. [Brookhaven National Lab., Upton, NY (United States)]|[State Univ. of New York, Stony Brook, NY (United States). Dept. of Physics

1992-09-01

477