National Library of Energy BETA

Sample records for beam accelerator concept

  1. PARTICLE ACCELERATORS; ACCELERATORS; BEAM DUMPS; BENDING; CHANNELING...

    Office of Scientific and Technical Information (OSTI)

    Channeling through Bent Crystals Mack, Stephanie; Ottawa U. SLAC 43 PARTICLE ACCELERATORS; ACCELERATORS; BEAM DUMPS; BENDING; CHANNELING; CRYSTAL LATTICES; DETECTION; FORTRAN;...

  2. CLASHING BEAM PARTICLE ACCELERATOR

    DOE Patents [OSTI]

    Burleigh, R.J.

    1961-04-11

    A charged-particle accelerator of the proton synchrotron class having means for simultaneously accelerating two separate contra-rotating particle beams within a single annular magnet structure is reported. The magnet provides two concentric circular field regions of opposite magnetic polarity with one field region being of slightly less diameter than the other. The accelerator includes a deflector means straddling the two particle orbits and acting to collide the two particle beams after each has been accelerated to a desired energy. The deflector has the further property of returning particles which do not undergo collision to the regular orbits whereby the particles recirculate with the possibility of colliding upon subsequent passages through the deflector.

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

    SciTech Connect (OSTI)

    Siemann, R.H.; /SLAC

    2011-10-24

    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.

  4. 2012 Advanced Accelerator Concepts Workshop

    SciTech Connect (OSTI)

    Downer, Michael C.

    2015-03-23

    We report on the organization and outcome of the 2012 Advanced Accelerator Concepts Workshop, held in Austin, Texas in June 2012.

  5. Accelerators AND Beams

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

    ... to energies far higher than usually found on earth. ... Implanting them very precisely in metal surfaces means ... of a Facility for Rare Isotope Beams (FRIB), an ...

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

    DOE Patents [OSTI]

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

    1984-03-22

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

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

    DOE Patents [OSTI]

    Birx, Daniel L.; Reginato, Louis L.

    1988-01-01

    An electron beam accelerator comprising an electron beam generator-injector to produce a focused beam of .gtoreq.0.1 MeV energy electrons; a plurality of substantially identical, aligned accelerator modules to sequentially receive and increase the kinetic energies of the beam electrons by about 0.1-1 MeV per module. Each accelerator module includes a pulse-forming network that delivers a voltage pulse to the module of substantially .gtoreq.0.1-1 MeV maximum energy over a time duration of .ltoreq.1 .mu.sec.

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

    DOE Patents [OSTI]

    Birx, Daniel L.; Reginato, Louis L.

    1987-01-01

    An electron beam accelerator comprising an electron beam generator-injector to produce a focused beam of .gtoreq.0.1 MeV energy electrons; a plurality of substantially identical, aligned accelerator modules to sequentially receive and increase the kinetic energies of the beam electrons by about 0.1-1 MeV per module. Each accelerator module includes a pulse-forming network that delivers a voltage pulse to the module of substantially 0.1-1 MeV maximum energy over a time duration of .ltoreq.1 .mu.sec.

  9. Advanced Accelerator Concepts Final Report

    SciTech Connect (OSTI)

    Wurtele, Jonathan S.

    2014-05-13

    physics motivation for our experiment, one that requires only a few dozen researchers but must effectively integrate plasma, accelerator, atomic, and fundamental physics, as well as combine numerous technologies in the control, manipulation, and measurement of neutral and non-neutral particles. The ELENA ring (to which we hope to contribute, should funding be provided) is expect, when completed, to significantly enhance the performance of antihydrogen trapping by increasing by a factor of 100 the number of antiprotons that can be successfully trapped and cooled. ELENA operation is scheduled to commence in 2017. In collaboration with LBNL scientists, we proposed a frictional cooling scheme. This is an alternative cooling method to that used by ELENA. It is less complicated, experimentally unproven, and produces a lower yield of cold antiprotons. Students and postdoctoral researchers work on the trapping, cooling, transport, and nonlinear dynamics of antiprotons bunches that are provided by the AD to ALPHA; they contribute to the operation of the experiment, to software development, and to the design and operation of experiments. Students are expected to spend at summers at CERN while taking courses; after completion of courses they typically reside at CERN for most of the half-year run. The Antiproton Decelerator [AD] at CERN, along with its experiments, is the only facility in the world where antiprotons can be trapped and cooled and combined with positrons to form cold antihydrogen, with the ultimate goal of studying CPT violation and, subsequently, gravitational interactions of antimatter. Beyond the ALPHA experiment, the group worked on beam physics problems including limits on the average current in a time-dependent period cathode and new methods to create longitudinally coherent high repetition rate soft x-ray sources and wide bandwidth mode locked x-ray lasers. We completed a detailed study of quantum mechanical effects in the transit time cooling of muons.

  10. Details and justifications for the MAP concept specification for acceleration above 63 GeV

    SciTech Connect (OSTI)

    Berg, J. Scott

    2014-02-28

    The Muon Accelerator Program (MAP) requires a concept specification for each of the accelerator systems. The Muon accelerators will bring the beam energy from a total energy of 63 GeV to the maximum energy that will fit on the Fermilab site. Justifications and supporting references are included, providing more detail than will appear in the concept specification itself.

  11. SLAC National Accelerator Laboratory FACET & TEST BEAM FACILITIES...

    Office of Scientific and Technical Information (OSTI)

    SLAC National Accelerator Laboratory FACET & TEST BEAM FACILITIES PROPOSAL Citation Details In-Document Search Title: SLAC National Accelerator Laboratory FACET & TEST BEAM ...

  12. Beam Dynamics Studies for a Laser Acceleration Experiment (Conference...

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: Beam Dynamics Studies for a Laser Acceleration Experiment The NLC Test Accelerator (NLCTA) at SLAC was built to address various beam ...

  13. Microwave accelerator E-beam pumped laser

    DOE Patents [OSTI]

    Brau, Charles A.; Stein, William E.; Rockwood, Stephen D.

    1980-01-01

    A device and method for pumping gaseous lasers by means of a microwave accelerator. The microwave accelerator produces a relativistic electron beam which is applied along the longitudinal axis of the laser through an electron beam window. The incident points of the electron beam on the electron beam window are varied by deflection coils to enhance the cooling characteristics of the foil. A thyratron is used to reliably modulate the microwave accelerator to produce electron beam pulses which excite the laser medium to produce laser pulse repetition frequencies not previously obtainable. An aerodynamic window is also disclosed which eliminates foil heating problems, as well as a magnetic bottle for reducing laser cavity length and pressures while maintaining efficient energy deposition.

  14. Notes on beam dynamics in linear accelerators

    SciTech Connect (OSTI)

    Gluckstern, R.L.

    1980-09-01

    A collection of notes, on various aspects of beam dynamics in linear accelerators, which were produced by the author during five years (1975 to 1980) of consultation for the LASL Accelerator Technology (AT) Division and Medium-Energy Physics (MP) Division is presented.

  15. 43 PARTICLE ACCELERATORS; ELECTRON GUNS; BEAM EMITTANCE; CHARGE

    Office of Scientific and Technical Information (OSTI)

    SPACE 430200* -- Particle Accelerators-- Beam Dynamics, Field Calculations, & Ion Optics The evolution of the electron-beam phase space distribution in laser-driven rf guns is...

  16. SLAC National Accelerator Laboratory FACET & TEST BEAM FACILITIES...

    Office of Scientific and Technical Information (OSTI)

    Laboratory FACET & TEST BEAM FACILITIES PROPOSAL Citation Details In-Document Search Title: SLAC National Accelerator Laboratory FACET & TEST BEAM FACILITIES PROPOSAL ...

  17. Method and apparatus for varying accelerator beam output energy

    DOE Patents [OSTI]

    Young, Lloyd M.

    1998-01-01

    A coupled cavity accelerator (CCA) accelerates a charged particle beam with rf energy from a rf source. An input accelerating cavity receives the charged particle beam and an output accelerating cavity outputs the charged particle beam at an increased energy. Intermediate accelerating cavities connect the input and the output accelerating cavities to accelerate the charged particle beam. A plurality of tunable coupling cavities are arranged so that each one of the tunable coupling cavities respectively connect an adjacent pair of the input, output, and intermediate accelerating cavities to transfer the rf energy along the accelerating cavities. An output tunable coupling cavity can be detuned to variably change the phase of the rf energy reflected from the output coupling cavity so that regions of the accelerator can be selectively turned off when one of the intermediate tunable coupling cavities is also detuned.

  18. High-energy accelerator for beams of heavy ions

    DOE Patents [OSTI]

    Martin, Ronald L.; Arnold, Richard C.

    1978-01-01

    An apparatus for accelerating heavy ions to high energies and directing the accelerated ions at a target comprises a source of singly ionized heavy ions of an element or compound of greater than 100 atomic mass units, means for accelerating the heavy ions, a storage ring for accumulating the accelerated heavy ions and switching means for switching the heavy ions from the storage ring to strike a target substantially simultaneously from a plurality of directions. In a particular embodiment the heavy ion that is accelerated is singly ionized hydrogen iodide. After acceleration, if the beam is of molecular ions, the ions are dissociated to leave an accelerated singly ionized atomic ion in a beam. Extraction of the beam may be accomplished by stripping all the electrons from the atomic ion to switch the beam from the storage ring by bending it in magnetic field of the storage ring.

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

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

    Shin, Young-Min

    2014-09-15

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

  20. COMPACT ACCELERATOR CONCEPT FOR PROTON THERAPY

    SciTech Connect (OSTI)

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

    2006-08-18

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

  1. Observation of Beam Loading in a Laser-Plasma Accelerator

    SciTech Connect (OSTI)

    Rechatin, C.; Ismail, A. Ben; Lim, J.; Faure, J.; Malka, V.; Davoine, X.; Lefebvre, E.; Lifschitz, A.

    2009-11-06

    Beam loading is the phenomenon which limits the charge and the beam quality in plasma based accelerators. An experimental study conducted with a laser-plasma accelerator is presented. Beam loading manifests itself through the decrease of the beam energy, the reduction of dark current, and the increase of the energy spread for large beam charge. 3D PIC simulations are compared to the experimental results and confirm the effects of beam loading. It is found that, in our experimental conditions, the trapped electron beams generate decelerating fields on the order of 1 (GV/m)/pC and that beam loading effects are optimized for trapped charges of about 20 pC.

  2. High-gradient two-beam electron accelerator

    SciTech Connect (OSTI)

    Hirshfield, Jay L.

    2014-11-04

    The main goal for this project was to design, build, and evaluate a detuned-cavity, collinear, two-beam accelerator structure. Testing was to be at the Yale University Beam Physics Laboratory, under terms of a sub-grant from Omega-P to Yale. Facilities available at Yale for this project include a 6-MeV S-band RF gun and associated beam line for forming and transporting a ~1 A drive beam , a 300 kV beam source for use as a test beam, and a full panoply of laboratory infrastructure and test equipment. During the first year of this project, availability and functionality of the 6-MeV drive beam and 300 kV test beam were confirmed, and the beam line was restored to a layout to be used with the two-beam accelerator project. Major efforts during the first year were also focused on computational design and simulation of the accelerator structure itself, on beam dynamics, and on beam transport. Effort during the second year was focussed on building and preparing to test the structure, including extensive cold testing. Detailed results from work under this project have been published in twelve archival journal articles, listed in Section IV of the technical report.

  3. Beam manipulation and acceleration with Dielectric-Lined Waveguides

    SciTech Connect (OSTI)

    Lemery, Francois

    2015-06-01

    The development of next-generation TeV+ electron accelerators will require either immense footprints based on conventional acceleraton techniques or the development of new higher{gradient acceleration methods. One possible alternative is beam-driven acceleration in a high-impedance medium such as a dielectric-lined-waveguide (DLW), where a highcharge bunch passes through a DLW and can excite gradients on the order of GV/m. An important characteristic of this acceleration class is the transformer ratio which characterizes the energy transfer of the scheme. This dissertation discusses alternative methods to improve the transformer ratio for beam-driven acceleration and also considers the use of DLWs for beam manipulation at low energy.

  4. Design Concepts for Muon-Based Accelerators (Conference) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Design Concepts for Muon-Based Accelerators Citation Details In-Document Search Title: Design Concepts for Muon-Based Accelerators You are accessing a document from the...

  5. Beam dynamics in a long-pulse linear induction accelerator

    SciTech Connect (OSTI)

    Ekdahl, Carl; Abeyta, Epifanio O; Aragon, Paul; Archuleta, Rita; Cook, Gerald; Dalmas, Dale; Esquibel, Kevin; Gallegos, Robert A; Garnett, Robert; Harrison, James F; Johnson, Jeffrey B; Jacquez, Edward B; Mc Cuistian, Brian T; Montoya, Nicholas A; Nath, Subrato; Nielsen, Kurt; Oro, David; Prichard, Benjamin; Rose, Chris R; Sanchez, Manolito; Schauer, Martin M; Seitz, Gerald; Schulze, Martin; Bender, Howard A; Broste, William B; Carlson, Carl A; Frayer, Daniel K; Johnson, Douglas E; Tom, C Y; Trainham, C; Williams, John; Scarpetti, Raymond; Genoni, Thomas; Hughes, Thomas; Toma, Carsten

    2010-01-01

    The second axis of the Dual Axis Radiography of Hydrodynamic Testing (DARHT) facility produces up to four radiographs within an interval of 1.6 microseconds. It accomplishes this by slicing four micro-pulses out of a long 1.8-kA, 16.5-MeV electron beam pulse and focusing them onto a bremsstrahlung converter target. The long beam pulse is created by a dispenser cathode diode and accelerated by the unique DARHT Axis-II linear induction accelerator (LIA). Beam motion in the accelerator would be a problem for radiography. High frequency motion, such as from beam breakup instability, would blur the individual spots. Low frequency motion, such as produced by pulsed power variation, would produce spot to spot differences. In this article, we describe these sources of beam motion, and the measures we have taken to minimize it.

  6. Electrostatic quadrupole focused particle accelerating assembly with laminar flow beam

    DOE Patents [OSTI]

    Maschke, A.W.

    1984-04-16

    A charged particle accelerating assembly provided with a predetermined ratio of parametric structural characteristics and with related operating voltages applied to each of its linearly spaced focusing and accelerating quadrupoles, thereby to maintain a particle beam traversing the electrostatic fields of the quadrupoles in the assembly in an essentially laminar flow through the assembly.

  7. Electrostatic quadrupole focused particle accelerating assembly with laminar flow beam

    DOE Patents [OSTI]

    Maschke, Alfred W.

    1985-01-01

    A charged particle accelerating assembly provided with a predetermined ratio of parametric structural characteristics and with related operating voltages applied to each of its linearly spaced focusing and accelerating quadrupoles, thereby to maintain a particle beam traversing the electrostatic fields of the quadrupoles in the assembly in an essentially laminar flow throughout the assembly.

  8. Beam Dynamics Design and Simulation in Ion Linear Accelerators (

    Energy Science and Technology Software Center (OSTI)

    2006-08-01

    Orginally, the ray tracing code TRACK has been developed to fulfill the many special requirements for the Rare Isotope Accelerator Facility known as RIA. Since no available beam-dynamics code met all the necessary requirements, modifications to the code TRACK were introduced to allow end-to-end (from the ion souce to the production target) simulations of the RIA machine, TRACK is a general beam-dynamics code and can be applied for the design, commissioning and operation of modernmore » ion linear accelerators and beam transport systems.« less

  9. 2D electron density profile measurement in tokamak by laser-accelerated ion-beam probe

    SciTech Connect (OSTI)

    Chen, Y. H.; Yang, X. Y.; Lin, C. E-mail: cjxiao@pku.edu.cn; Wang, X. G.; Xiao, C. J. E-mail: cjxiao@pku.edu.cn; Wang, L.; Xu, M.

    2014-11-15

    A new concept of Heavy Ion Beam Probe (HIBP) diagnostic has been proposed, of which the key is to replace the electrostatic accelerator of traditional HIBP by a laser-driven ion accelerator. Due to the large energy spread of ions, the laser-accelerated HIBP can measure the two-dimensional (2D) electron density profile of tokamak plasma. In a preliminary simulation, a 2D density profile was reconstructed with a spatial resolution of about 2 cm, and with the error below 15% in the core region. Diagnostics of 2D density fluctuation is also discussed.

  10. Numerical Verification of the Power Transfer and Wakefield Coupling in the Clic Two-Beam Accelerator

    SciTech Connect (OSTI)

    Candel, Arno; Li, Z.; Ng, C.; Rawat, V.; Schussman, G.; Ko, K.; Syratchev, I.; Grudiev, A.; Wuensch, W.; /CERN

    2011-08-19

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

  11. Profile of single-pulsed ion beams in acceleration gap

    SciTech Connect (OSTI)

    Xiang, W.; Tang, P.Y.

    2006-03-15

    In an attempt to understand the characteristics of single-pulsed ion beams extracted from a miniature occluded-gas sources with electrodes of metallic hydride, a two-dimensional (2D) projected image of ion beams extracted from the single-pulsed occluded-gas source was captured using a digital charge-coupled device camera on a test bench. Based on image processing and the inverse Abel transform, the 2D integrally projected image with cylindrical symmetry was used to determine the profile of ion beams in the acceleration gap. The result shows that the radial beam profile in acceleration gap has a Gaussian-like shape, and the maximum beam intensity behind the plasma electrode is about 40% higher than that in front of the extraction electrode.

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

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

    Shin, Young-Min

    2014-09-15

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

  13. Beam On Target! - CEBAF Accelerator Achieves 12 GeV Commissioning...

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

    Beam On Target - CEBAF Accelerator Achieves 12 GeV Commissioning Milestone Beam On Target CEBAF Accelerator Achieves 12 GeV Commissioning Milestone The accelerator crew on hand ...

  14. Realizing novel accelerator concepts in an X-band photo-injector

    SciTech Connect (OSTI)

    Marsh, R

    2010-04-13

    In this project we propose to investigate the use of novel accelerator structure cell geometry to enhance the performance of X-band photo-injectors. Making novel accelerator concepts possible involves fabrication and testing of components to ensure that the performance predicted by simulation is robustly achievable. This work is important because photo-injectors are increasingly used to provide high brightness electron beams for light sources, pushing their performance to the limits, but also requiring them to be user-facility stable. Careful investigation in both computer simulation and design, and low power testing of piece parts will enable the successful fabrication of an advanced X-band photo-injector.

  15. Concept for high-charge-state ion induction accelerators

    SciTech Connect (OSTI)

    Logan, B.G.; Perry, M.D.; Caporaso, G.J.

    1996-11-15

    This work describes a particular concept for ion induction linac accelerators using high-charge-state ions produced by an intense, short pulse laser, and compares the costs of a modular driver system producing 6.5 MJ for a variety of ion masses and charge states using a simple but consistent cost model.

  16. Beam On Target! - CEBAF Accelerator Achieves 12 GeV Commissioning Milestone

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

    | Jefferson Lab Beam On Target! - CEBAF Accelerator Achieves 12 GeV Commissioning Milestone Beam On Target! CEBAF Accelerator Achieves 12 GeV Commissioning Milestone The accelerator crew on hand The accelerator crew on hand for the beam-on-target achievement included (l-r) Crew Chief Mike McCaughan, Accelerator Operators Dan Moser and Brandi Cade. Yves Roblin was the Accelerator Physics Experimental Liaison for the Hall A beamline, Accelerator Scientist Yan Wang recorded and provided insight

  17. A new concept for accelerator driven transmutation of nuclear wastes

    SciTech Connect (OSTI)

    Arthur, E.D.

    1991-01-01

    A new concept for an accelerator-driven transmutation system is described. The central feature of the concept is generation of intense fluxes of thermal neutrons. In the system all long-lived radionuclides comprising high-level nuclear waste can be transmuted efficiently. Transmutation takes place in a unique, low material inventory environment. Presently two principal areas are being investigated for application of the concept. The first is associated with cleanup of defense high-level waste at DOE sites such as Hanford. The second, longer term area involves production of electric power using a coupled accelerator-multiplying blanket system. This system would utilize natural thorium or uranium and would transmute long-lived components of high-level waste concurrently during operation. 5 refs., 5 figs.

  18. Beam loading and cavity compensation for the ground test accelerator

    SciTech Connect (OSTI)

    Jachim, S.P.; Natter, E.F.

    1989-01-01

    The Ground Test Accelerator (GTA) will be a heavily beam-loaded H/sup minus/ linac with tight tolerances on accelerating field parameters. The methods used in modeling the effects of beam loading in this machine are described. The response of the cavity to both beam and radio-frequency (RF) drive stimulus is derived, including the effects of cavity detuning. This derivation is not restricted to a small-signal approximation. An analytical method for synthesizing a predistortion network that decouples the amplitude and phase responses of the cavity is also outlined. Simulation of performance, including beam loading, is achieved through use of a control system analysis software package. A straightforward method is presented for extrapolating this work to model large coupled structures with closely spaced parasitic modes. Results to date have enabled the RF control system designs for GTA to be optimized and have given insight into their operation. 6 refs., 10 figs.

  19. Iron beam acceleration using direct plasma injection scheme

    SciTech Connect (OSTI)

    Okamura, M.; Kanesue, T.; Yamamoto, T.; Fuwa, Y.; RIKEN, Wako, Saitama 351-0198

    2014-02-15

    A new set of vanes of radio frequency quadrupole (RFQ) accelerator was commissioned using highly charged iron beam. To supply high intensity heavy ion beams to the RFQ, direct plasma injection scheme (DPIS) with a confinement solenoid was adopted. One of the difficulties to utilize the combination of DPIS and a solenoid field is a complexity of electro magnetic field at the beam extraction region, since biasing high static electric field for ion extraction, RFQ focusing field, and the solenoid magnetic field fill the same space simultaneously. To mitigate the complexity, a newly designed magnetic field clamps were used. The intense iron beam was observed with bunched structure and the total accelerated current reached 2.5 nC.

  20. Beam manipulation techniques, nonlinear beam dynamics, and space charge effect in high energy high power accelerators

    SciTech Connect (OSTI)

    Lee, S. Y.

    2014-04-07

    We had carried out a design of an ultimate storage ring with beam emittance less than 10 picometer for the feasibility of coherent light source at X-ray wavelength. The accelerator has an inherent small dynamic aperture. We study method to improve the dynamic aperture and collective instability for an ultimate storage ring. Beam measurement and accelerator modeling are an integral part of accelerator physics. We develop the independent component analysis (ICA) and the orbit response matrix method for improving accelerator reliability and performance. In collaboration with scientists in National Laboratories, we also carry out experimental and theoretical studies on beam dynamics. Our proposed research topics are relevant to nuclear and particle physics using high brightness particle and photon beams.

  1. Physics of beam self-modulation in plasma wakefield accelerators

    SciTech Connect (OSTI)

    Lotov, K. V.

    2015-10-15

    The self-modulation instability is a key effect that makes possible the usage of nowadays proton beams as drivers for plasma wakefield acceleration. Development of the instability in uniform plasmas and in plasmas with a small density up-step is numerically studied with the focus at nonlinear stages of beam evolution. The step parameters providing the strongest established wakefield are found, and the mechanism of stable bunch train formation is identified.

  2. ACE3P Computations of Wakefield Coupling in the CLIC Two-Beam Accelerator

    SciTech Connect (OSTI)

    Candel, Arno; Li, Z.; Ng, C.; Rawat, V.; Schussman, G.; Ko, K.; Syratchev, I.; Grudiev, A.; Wuensch, W.

    2010-10-27

    The Compact Linear Collider (CLIC) provides a path to a multi-TeV accelerator to explore the energy frontier of High Energy Physics. Its novel two-beam accelerator concept envisions rf power transfer to the accelerating structures from a separate high-current decelerator beam line consisting of power extraction and transfer structures (PETS). It is critical to numerically verify the fundamental and higher-order mode properties in and between the two beam lines with high accuracy and confidence. To solve these large-scale problems, SLAC's parallel finite element electromagnetic code suite ACE3P is employed. Using curvilinear conformal meshes and higher-order finite element vector basis functions, unprecedented accuracy and computational efficiency are achieved, enabling high-fidelity modeling of complex detuned structures such as the CLIC TD24 accelerating structure. In this paper, time-domain simulations of wakefield coupling effects in the combined system of PETS and the TD24 structures are presented. The results will help to identify potential issues and provide new insights on the design, leading to further improvements on the novel CLIC two-beam accelerator scheme.

  3. Indirectly sensing accelerator beam currents for limiting maximum beam current magnitude

    DOE Patents [OSTI]

    Bogaty, J.M.; Clifft, B.E.; Bollinger, L.M.

    1995-08-08

    A beam current limiter is disclosed for sensing and limiting the beam current in a particle accelerator, such as a cyclotron or linear accelerator, used in scientific research and medical treatment. A pair of independently operable capacitive electrodes sense the passage of charged particle bunches to develop an RF signal indicative of the beam current magnitude produced at the output of a bunched beam accelerator. The RF signal produced by each sensing electrode is converted to a variable DC voltage indicative of the beam current magnitude. The variable DC voltages thus developed are compared to each other to verify proper system function and are further compared to known references to detect beam currents in excess of pre-established limits. In the event of a system malfunction, or if the detected beam current exceeds pre-established limits, the beam current limiter automatically inhibits further accelerator operation. A high Q tank circuit associated with each sensing electrode provides a narrow system bandwidth to reduce noise and enhance dynamic range. System linearity is provided by injecting, into each sensing electrode, an RF signal that is offset from the bunching frequency by a pre-determined beat frequency to ensure that subsequent rectifying diodes operate in a linear response region. The system thus provides a large dynamic range in combination with good linearity. 6 figs.

  4. Indirectly sensing accelerator beam currents for limiting maximum beam current magnitude

    DOE Patents [OSTI]

    Bogaty, John M.; Clifft, Benny E.; Bollinger, Lowell M.

    1995-01-01

    A beam current limiter for sensing and limiting the beam current in a particle accelerator, such as a cyclotron or linear accelerator, used in scientific research and medical treatment. A pair of independently operable capacitive electrodes sense the passage of charged particle bunches to develop an RF signal indicative of the beam current magnitude produced at the output of a bunched beam accelerator. The RF signal produced by each sensing electrode is converted to a variable DC voltage indicative of the beam current magnitude. The variable DC voltages thus developed are compared to each other to verify proper system function and are further compared to known references to detect beam currents in excess of pre-established limits. In the event of a system malfunction, or if the detected beam current exceeds pre-established limits, the beam current limiter automatically inhibits further accelerator operation. A high Q tank circuit associated with each sensing electrode provides a narrow system bandwidth to reduce noise and enhance dynamic range. System linearity is provided by injecting, into each sensing electrode, an RF signal that is offset from the bunching frequency by a pre-determined beat frequency to ensure that subsequent rectifying diodes operate in a linear response region. The system thus provides a large dynamic range in combination with good linearity.

  5. Experience with the ground test accelerator beam-measurement instrumentation

    SciTech Connect (OSTI)

    Gilpatrick, J.D.; Johnson, K.F.; Connolly, R.C.; Power, J.F.; Rose, C.R.; Sander, O.R.; Shafer, R.E.; Sandoval, D.P.; Yuan, V.W. )

    1994-10-10

    During the past two years, the Ground Test Accelerator (GTA) has used a variety of off- and on-line beam diagnostic measurements to understand and verify the transverse and longitudinal phase space characteristics of a 35-mA, low-energy (2.5- to 3.2-MeV) H[sup [minus

  6. Observation of laser multiple filamentation process and multiple electron beams acceleration in a laser wakefield accelerator

    SciTech Connect (OSTI)

    Li, Wentao; Liu, Jiansheng; Wang, Wentao; Chen, Qiang; Zhang, Hui; Tian, Ye; Zhang, Zhijun; Qi, Rong; Wang, Cheng; Leng, Yuxin; Li, Ruxin; Xu, Zhizhan

    2013-11-15

    The multiple filaments formation process in the laser wakefield accelerator (LWFA) was observed by imaging the transmitted laser beam after propagating in the plasma of different density. During propagation, the laser first self-focused into a single filament. After that, it began to defocus with energy spreading in the transverse direction. Two filaments then formed from it and began to propagate independently, moving away from each other. We have also demonstrated that the laser multiple filamentation would lead to the multiple electron beams acceleration in the LWFA via ionization-induced injection scheme. Besides, its influences on the accelerated electron beams were also analyzed both in the single-stage LWFA and cascaded LWFA.

  7. Relativistic-Klystron two-beam accelerator as a power source for future linear colliders

    SciTech Connect (OSTI)

    Lidia, S. M.; Anderson, D. E.; Eylon, S.; Henestroza, E.; Vanecek, D. L.; Yu, S. S. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Houck, T. L.; Westenskow, G. A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    1999-05-07

    The technical challenge for making two-beam accelerators into realizable power sources for high-energy colliders lies in the creation of the drive beam and in its propagation over long distances through multiple extraction sections. This year we have been constructing a 1.2-kA, 1-MeV, induction gun for a prototype relativistic klystron two-beam accelerator (RK-TBA). The electron source will be a 8.9 cm diameter, thermionic, flat-surface cathode with a maximum shroud field stress of approximately 165 kV/cm. Additional design parameters for the injector include a pulse length of over 150-ns flat top (1% energy variation), and a normalized edge emittance of less than 300 pi-mm-mr. The prototype accelerator will be used to study, physics, engineering, and costing issues involved in the application of the RK-TBA concept to linear colliders. We have also been studying optimization parameters, such as frequency, for the application of the RK-TBA concept to multi-TeV linear colliders. As an rf power source the RK-TBA scales favorably up to frequencies around 35 GHz. An overview of this work with details of the design and performance of the prototype injector, beam line, and diagnostics will be presented.

  8. Relativistic-Klystron two-beam accelerator as a power source for future linear colliders

    SciTech Connect (OSTI)

    Lidia, S.M.; Anderson, D.E.; Eylon, S.; Henestroza, E.; Vanecek, D.L.; Yu, S.S. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Westenskow, G.A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    1999-05-01

    The technical challenge for making two-beam accelerators into realizable power sources for high-energy colliders lies in the creation of the drive beam and in its propagation over long distances through multiple extraction sections. This year we have been constructing a 1.2-kA, 1-MeV, induction gun for a prototype relativistic klystron two-beam accelerator (RK-TBA). The electron source will be a 8.9 cm diameter, thermionic, flat-surface cathode with a maximum shroud field stress of approximately 165 kV/cm. Additional design parameters for the injector include a pulse length of over 150-ns flat top (1{percent} energy variation), and a normalized edge emittance of less than 300 pi-mm-mr. The prototype accelerator will be used to study, physics, engineering, and costing issues involved in the application of the RK-TBA concept to linear colliders. We have also been studying optimization parameters, such as frequency, for the application of the RK-TBA concept to multi-TeV linear colliders. As an rf power source the RK-TBA scales favorably up to frequencies around 35 GHz. An overview of this work with details of the design and performance of the prototype injector, beam line, and diagnostics will be presented. {copyright} {ital 1999 American Institute of Physics.}

  9. Relativistic-klystron two-beam accelerator as a power source for future linear colliders

    SciTech Connect (OSTI)

    Anderson, D E; Eylon, S; Henestroza, E; Houck, T L; Lidia, M; Vanecek, D L; Westenskow, G A; Yu, S S

    1998-10-05

    The technical challenge for making two-beam accelerators into realizable power sources for high-energy colliders lies in the creation of the drive beam and in its propagation over long distances through multiple extraction sections. This year we have been constructing a 1.2&A, l-MeV, induction gun for a prototype relativistic klystron two-beam accelerator (RK-TBA). The electron source will be a 8.9 cm diameter, thermionic, flat-surface cathode with a maximum shroud field stress of approximately 165 kV/cm. Additional design parameters for the injector include a pulse length of over 150-ns flat top (1% energy variation), and a normalized edge emittance of less than 300 pi-mm-n-n. The prototype accelerator will be used to study physics, engineering, and costing issues involved in the application of the RK-TBA concept to linear colliders. We have also been studying optimization parameters, such as frequency, for the application of the RK-TBA concept to multi-TeV linear colliders. As an rf power source the RK-TBA scales favorably up to frequencies around 35 GHz. An overview of this work with details of the design and performance of the prototype injector, beam line, and diagnostics will be presented.

  10. Radio Frequency Station - Beam Dynamics Interaction in Circular Accelerators

    SciTech Connect (OSTI)

    Mastoridis, Themistoklis; /Stanford U., Elect. Eng. Dept. /SLAC

    2011-03-01

    The longitudinal beam dynamics in circular accelerators is mainly defined by the interaction of the beam current with the accelerating Radio Frequency (RF) stations. For stable operation, Low Level RF (LLRF) feedback systems are employed to reduce coherent instabilities and regulate the accelerating voltage. The LLRF system design has implications for the dynamics and stability of the closed-loop RF systems as well as for the particle beam, and is very sensitive to the operating range of accelerator currents and energies. Stability of the RF loop and the beam are necessary conditions for reliable machine operation. This dissertation describes theoretical formalisms and models that determine the longitudinal beam dynamics based on the LLRF implementation, time domain simulations that capture the dynamic behavior of the RF station-beam interaction, and measurements from the Positron-Electron Project (PEP-II) and the Large Hadron Collider (LHC) that validate the models and simulations. These models and simulations are structured to capture the technical characteristics of the system (noise contributions, non-linear elements, and more). As such, they provide useful results and insight for the development and design of future LLRF feedback systems. They also provide the opportunity to study diverse longitudinal beam dynamics effects such as coupled-bunch impedance driven instabilities and single bunch longitudinal emittance growth. Coupled-bunch instabilities and RF station power were the performance limiting effects for PEP-II. The sensitivity of the instabilities to individual LLRF parameters, the effectiveness of alternative operational algorithms, and the possible tradeoffs between RF loop and beam stability were studied. New algorithms were implemented, with significant performance improvement leading to a world record current during the last PEP-II run of 3212 mA for the Low Energy Ring. Longitudinal beam emittance growth due to RF noise is a major concern for LHC

  11. 9 GeV energy gain in a beam-driven plasma wakefield accelerator...

    Office of Scientific and Technical Information (OSTI)

    9 GeV energy gain in a beam-driven plasma wakefield accelerator Citation Details In-Document Search Title: 9 GeV energy gain in a beam-driven plasma wakefield accelerator An ...

  12. Design Concepts for Muon-Based Accelerators (Conference) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Design Concepts for Muon-Based Accelerators Citation Details In-Document Search Title: Design Concepts for Muon-Based Accelerators Authors: Ryne, R.D. ; et al. Publication Date: ...

  13. Study of a multi-beam accelerator driven thorium reactor

    SciTech Connect (OSTI)

    Ludewig, H.; Aronson, A.

    2011-03-01

    The primary advantages that accelerator driven systems have over critical reactors are: (1) Greater flexibility regarding the composition and placement of fissile, fertile, or fission product waste within the blanket surrounding the target, and (2) Potentially enhanced safety brought about by operating at a sufficiently low value of the multiplication factor to preclude reactivity induced events. The control of the power production can be achieved by vary the accelerator beam current. Furthermore, once the beam is shut off the system shuts down. The primary difference between the operation of an accelerator driven system and a critical system is the issue of beam interruptions of the accelerator. These beam interruptions impose thermo-mechanical loads on the fuel and mechanical components not found in critical systems. Studies have been performed to estimate an acceptable number of trips, and the value is significantly less stringent than had been previously estimated. The number of acceptable beam interruptions is a function of the length of the interruption and the mission of the system. Thus, for demonstration type systems and interruption durations of 1sec < t < 5mins, and t > 5mins 2500/yr and 50/yr are deemed acceptable. However, for industrial scale power generation without energy storage type systems and interruption durations of t < 1sec., 1sec < t < 10secs., 10secs < t < 5mins, and t > 5mins, the acceptable number of interruptions are 25000, 2500, 250, and 3 respectively. However, it has also been concluded that further development is required to reduce the number of trips. It is with this in mind that the following study was undertaken. The primary focus of this study will be the merit of a multi-beam target system, which allows for multiple spallation sources within the target/blanket assembly. In this manner it is possible to ameliorate the effects of sudden accelerator beam interruption on the surrounding reactor, since the remaining beams will still

  14. Simulation of Current Filamentation Instability for an Accelerator Beam in a Capillary Plasma

    SciTech Connect (OSTI)

    Allen, Brian; Seyedi, Ashkan; Muggli, Patric; Martins, Joana; Silva, Luis O.; Huang Chengkun; Mori, Warren

    2010-11-04

    Current Filamentation Instability (CFI) is of central importance for the propagation of relativistic electron beams in plasmas. It could play an important role in the generation of magnetic fields and of radiation in the after-glow of gamma ray bursts as well as in hot electrons energy transport in the fast-igniter inertial confinement fusion concept. Using the particle-in-cell code QuickPIC, simulations of the electron beam at the Brookhaven National Laboratory--Accelerator Test Facility, BNL-ATF, propagating in a cm-long plasma were conducted. Simulation results show that with beam and plasma parameters achievable at the BNL-ATF, the CFI should be observed within 2 cm of plasma. Simulation results are presented for an experiment currently underway at BNL-ATF and possible diagnostics for characterizing the instability are discussed.

  15. The APEX Project: Ion beam pulse-shaping experiments on Sandia Laboratories' Particle Beam Fusion Accelerator PBFA II

    SciTech Connect (OSTI)

    Crow, J.T.

    1987-01-01

    This paper discusses the development of ion beam pulse shaping, efficient extraction ion diodes, and efficient plasma channel transport for the particle beam fusion accelerator PBFA II. 10 refs. (LSP)

  16. Electron Beam Charge Diagnostics for Laser Plasma Accelerators

    SciTech Connect (OSTI)

    Nakamura, Kei; Gonsalves, Anthony; Lin, Chen; Smith, Alan; Rodgers, David; Donahue, Rich; Byrne, Warren; Leemans, Wim

    2011-06-27

    A comprehensive study of charge diagnostics is conducted to verify their validity for measuring electron beams produced by laser plasma accelerators (LPAs). First, a scintillating screen (Lanex) was extensively studied using subnanosecond electron beams from the Advanced Light Source booster synchrotron, at the Lawrence Berkeley National Laboratory. The Lanex was cross calibrated with an integrating current transformer (ICT) for up to the electron energy of 1.5 GeV, and the linear response of the screen was confirmed for charge density and intensity up to 160 pC/mm{sup 2} and 0.4 pC/(ps mm{sup 2}), respectively. After the radio-frequency accelerator based cross calibration, a series of measurements was conducted using electron beams from an LPA. Cross calibrations were carried out using an activation-based measurement that is immune to electromagnetic pulse noise, ICT, and Lanex. The diagnostics agreed within {+-}8%, showing that they all can provide accurate charge measurements for LPAs.

  17. Laser-driven ion acceleration with hollow laser beams

    SciTech Connect (OSTI)

    Brabetz, C. Kester, O.; Busold, S.; Bagnoud, V.; Cowan, T.; Deppert, O.; Jahn, D.; Roth, M.; Schumacher, D.

    2015-01-15

    The laser-driven acceleration of protons from thin foils irradiated by hollow high-intensity laser beams in the regime of target normal sheath acceleration (TNSA) is reported for the first time. The use of hollow beams aims at reducing the initial emission solid angle of the TNSA source, due to a flattening of the electron sheath at the target rear side. The experiments were conducted at the PHELIX laser facility at the GSI Helmholtzzentrum für Schwerionenforschung GmbH with laser intensities in the range from 10{sup 18} W cm{sup −2} to 10{sup 20} W cm{sup −2}. We observed an average reduction of the half opening angle by (3.07±0.42)° or (13.2±2.0)% when the targets have a thickness between 12 μm and 14 μm. In addition, the highest proton energies were achieved with the hollow laser beam in comparison to the typical Gaussian focal spot.

  18. Beam Matching to a Plasma Wakefield Accelerator Using a Ramped Density

    Office of Scientific and Technical Information (OSTI)

    Profile at the Plasma Boundary (Conference) | SciTech Connect Conference: Beam Matching to a Plasma Wakefield Accelerator Using a Ramped Density Profile at the Plasma Boundary Citation Details In-Document Search Title: Beam Matching to a Plasma Wakefield Accelerator Using a Ramped Density Profile at the Plasma Boundary An important aspect of plasma wake field accelerators (PWFA) is stable propagation of the drive beam. In the under dense plasma regime, the drive beam creates an ion channel

  19. Electron Beam Transport in Advanced Plasma Wave Accelerators

    SciTech Connect (OSTI)

    Williams, Ronald L

    2013-01-31

    The primary goal of this grant was to develop a diagnostic for relativistic plasma wave accelerators based on injecting a low energy electron beam (5-50keV) perpendicular to the plasma wave and observing the distortion of the electron beam's cross section due to the plasma wave's electrostatic fields. The amount of distortion would be proportional to the plasma wave amplitude, and is the basis for the diagnostic. The beat-wave scheme for producing plasma waves, using two CO2 laser beam, was modeled using a leap-frog integration scheme to solve the equations of motion. Single electron trajectories and corresponding phase space diagrams were generated in order to study and understand the details of the interaction dynamics. The electron beam was simulated by combining thousands of single electrons, whose initial positions and momenta were selected by random number generators. The model was extended by including the interactions of the electrons with the CO2 laser fields of the beat wave, superimposed with the plasma wave fields. The results of the model were used to guide the design and construction of a small laboratory experiment that may be used to test the diagnostic idea.

  20. Acceleration and stability of a high-current ion beam in induction fields

    SciTech Connect (OSTI)

    Karas', V. I.; Manuilenko, O. V.; Tarakanov, V. P.; Federovskaya, O. V.

    2013-03-15

    A one-dimensional nonlinear analytic theory of the filamentation instability of a high-current ion beam is formulated. The results of 2.5-dimensional numerical particle-in-cell simulations of acceleration and stability of an annular compensated ion beam (CIB) in a linear induction particle accelerator are presented. It is shown that additional transverse injection of electron beams in magnetically insulated gaps (cusps) improves the quality of the ion-beam distribution function and provides uniform beam acceleration along the accelerator. The CIB filamentation instability in both the presence and the absence of an external magnetic field is considered.

  1. Continuous Electron Beam Accelerator Facility (CEBAF) | U.S. DOE Office of

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

    Science (SC) Continuous Electron Beam Accelerator Facility (CEBAF) Nuclear Physics (NP) NP Home About Research Facilities User Facilities Argonne Tandem Linac Accelerator System (ATLAS) Continuous Electron Beam Accelerator Facility (CEBAF) Relativistic Heavy Ion Collider (RHIC) Project Development Isotope Program Facilities Science Highlights Benefits of NP Funding Opportunities Nuclear Science Advisory Committee (NSAC) Community Resources Contact Information Nuclear Physics U.S. Department

  2. Organization of the 16th Advanced Accelerator Concepts (AAC) Workshop by Stanford University

    SciTech Connect (OSTI)

    Huang, Zhirong; Hogan, Mark

    2015-09-30

    Essentially all we know today and will learn in the future about the fundamental nature of matter is derived from probing it with directed beams of particles such as electrons, protons, neutrons, heavy ions, and photons. The resulting ability to “see” the building blocks of matter has had an immense impact on society and our standard of living. Over the last century, particle accelerators have changed the way we look at nature and the universe we live in and have become an integral part of the Nation’s technical infrastructure. Today, particle accelerators are essential tools of modern science and technology. The cost and capabilities of accelerators would be greatly enhanced by breakthroughs in acceleration methods and technology. For the last 32 years, the Advanced Accelerator Concepts (AAC) Workshop has acted as the focal point for discussion and development of the most promising acceleration physics and technology. It is a particularly effective forum where the discussion is leveraged and promoted by the unique and demanding feature of the AAC Workshop: the working group structure, in which participants are asked to consider their contributions in terms of even larger problems to be solved. The 16th Advanced Accelerator Concepts (AAC2014) Workshop was organized by Stanford University from July 13 - 18, 2014 at the Dolce Hays Mansion in San Jose, California. The conference had a record 282 attendees including 62 students. Attendees came from 11 countries representing 66 different institutions. The workshop format consisted of plenary sessions in the morning with topical leaders from around the world presenting the latest breakthroughs to the entire workshop. In the late morning and afternoons attendees broke out into eight different working groups for more detailed presentations and discussions that were summarized on the final day of the workshop. In addition, there were student tutorial presentations on two afternoons to provide in depth education and

  3. Automatic Beam Path Analysis of Laser Wakefield Particle Acceleration Data

    SciTech Connect (OSTI)

    Rubel, Oliver; Geddes, Cameron G.R.; Cormier-Michel, Estelle; Wu, Kesheng; Prabhat,; Weber, Gunther H.; Ushizima, Daniela M.; Messmer, Peter; Hagen, Hans; Hamann, Bernd; Bethel, E. Wes

    2009-10-19

    Numerical simulations of laser wakefield particle accelerators play a key role in the understanding of the complex acceleration process and in the design of expensive experimental facilities. As the size and complexity of simulation output grows, an increasingly acute challenge is the practical need for computational techniques that aid in scientific knowledge discovery. To that end, we present a set of data-understanding algorithms that work in concert in a pipeline fashion to automatically locate and analyze high energy particle bunches undergoing acceleration in very large simulation datasets. These techniques work cooperatively by first identifying features of interest in individual timesteps, then integrating features across timesteps, and based on the information derived perform analysis of temporally dynamic features. This combination of techniques supports accurate detection of particle beams enabling a deeper level of scientific understanding of physical phenomena than hasbeen possible before. By combining efficient data analysis algorithms and state-of-the-art data management we enable high-performance analysis of extremely large particle datasets in 3D. We demonstrate the usefulness of our methods for a variety of 2D and 3D datasets and discuss the performance of our analysis pipeline.

  4. Beam Matching to a Plasma Wakefield Accelerator Using a Ramped...

    Office of Scientific and Technical Information (OSTI)

    ... Sponsoring Org: USDOE Country of Publication: United States Language: English Subject: 43 PARTICLE ACCELERATORS; ACCELERATORS; BETATRON OSCILLATIONS; FOCUSING; PLASMA; STANFORD ...

  5. Beam Matching to a Plasma Wakefield Accelerator Using a Ramped...

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: USDOE Country of Publication: United States Language: English Subject: 43 PARTICLE ACCELERATORS; ACCELERATORS; BETATRON OSCILLATIONS; FOCUSING; PLASMA; STANFORD ...

  6. Demonstration of two-beam acceleration and 30 GHz power production in the CLIC Test Facility

    SciTech Connect (OSTI)

    Bossart, R.; Braun, H. H.; Carron, G.; Chanudet, M.; Chautard, F.; Delahaye, J. P.; Godot, J. C.; Hutchins, S.; Martinez, C.; Suberlucq, G.; Tenenbaum, P.; Thorndahl, L.; Trautner, H.; Valentini, M.; Wilson, I.; Wuensch, W. [CERN, 1211 Geneva 23 (Switzerland)

    1999-05-07

    The Compact Linear Collider (CLIC) Test Facility (CTF II) at CERN has recently demonstrated Two-Beam power production and acceleration at 30 GHz. With 41 MW of 30 GHz power produced in 14 ns pulses at a repetition rate of 5 Hz, the main beam has been accelerated by 28 MeV. The 30 GHz RF power is extracted in low impedance decelerating structures from a low-energy, high-current 'drive beam' which runs parallel to the main beam. The average current in the drive-beam train is 25 A, while the peak current exceeds 2 kA. Crosschecks between measured drive-beam charge, 30 GHz power and main-beam energy gain are in good agreement. In this paper, some relevant experimental and technical issues on drive-beam generation, two-beam power production and acceleration are presented.

  7. Electron-beam dynamics for an advanced flash-radiography accelerator

    SciTech Connect (OSTI)

    Ekdahl, Carl August Jr.

    2015-06-22

    Beam dynamics issues were assessed for a new linear induction electron accelerator. Special attention was paid to equilibrium beam transport, possible emittance growth, and beam stability. Especially problematic would be high-frequency beam instabilities that could blur individual radiographic source spots, low-frequency beam motion that could cause pulse-to-pulse spot displacement, and emittance growth that could enlarge the source spots. Beam physics issues were examined through theoretical analysis and computer simulations, including particle-in cell (PIC) codes. Beam instabilities investigated included beam breakup (BBU), image displacement, diocotron, parametric envelope, ion hose, and the resistive wall instability. Beam corkscrew motion and emittance growth from beam mismatch were also studied. It was concluded that a beam with radiographic quality equivalent to the present accelerators at Los Alamos will result if the same engineering standards and construction details are upheld.

  8. Means and method for the focusing and acceleration of parallel beams of charged particles

    DOE Patents [OSTI]

    Maschke, Alfred W.

    1983-07-05

    A novel apparatus and method for focussing beams of charged particles comprising planar arrays of electrostatic quadrupoles. The quadrupole arrays may comprise electrodes which are shared by two or more quadrupoles. Such quadrupole arrays are particularly adapted to providing strong focussing forces for high current, high brightness, beams of charged particles, said beams further comprising a plurality of parallel beams, or beamlets, each such beamlet being focussed by one quadrupole of the array. Such arrays may be incorporated in various devices wherein beams of charged particles are accelerated or transported, such as linear accelerators, klystron tubes, beam transport lines, etc.

  9. Studies of beam dynamics in relativistic klystron two-beam accelerators

    SciTech Connect (OSTI)

    Lidia, Steven M.

    1999-11-01

    Two-beam accelerators (TBAs) based upon free-electron lasers (FELs) or relativistic klystrons (RK-TBAs) have been proposed as efficient power sources for next generation high-energy linear colliders. Studies have demonstrated the possibility of building TBAs from X-band ({approximately}8-12 GHz) through Ka band ({approximately} 30-35 GHz) frequency regions. Provided that further prototyping shows stable beam propagation with minimal current loss and production of good quality, high-power rf fields, this technology is compatible with current schemes for electron-positron colliders in the multi-TeV center-of-mass scale. A new method of simulating the beam dynamics in accelerators of this type has been developed in this dissertation. There are three main components to this simulation. The first is a tracking algorithm to generate nonlinear transfer maps for pushing noninteracting particles through the external fields. The second component is a 3D Particle-In-Cell (PIC) algorithm that solves a set of Helmholtz equations for the self-fields, including the conducting boundary condition, and generates impulses that are interleaved with the nonlinear maps by means of a split-operation algorithm. The Helmholtz equations are solved by a multi-grid algorithm. The third component is an equivalent circuit equation solver that advances the modal rf cavity fields in time due to excitation by the modulated beam. The RTA project is described, and the simulation code is used to design the latter portions of the experiment. Detailed calculations of the beam dynamics and of the rf cavity output are presented and discussed. A beamline design is presented that will generate nearly 1.2 GW of power from 40 input, gain, and output rv cavities over a 10 m distance. The simulations show that beam current losses are acceptable, and that longitudinal and transverse focusing techniques are sufficient capable of maintaining a high degree of beam quality along the entire beamline. Additional

  10. Demonstration of a positron beam-driven hollow channel plasma wakefield accelerator

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

    Gessner, Spencer; Adli, Erik; Allen, James M.; An, Weiming; Clarke, Christine I.; Clayton, Chris E.; Corde, Sebastien; Delahaye, J. P.; Frederico, Joel; Green, Selina Z.; et al

    2016-06-02

    Plasma wakefield accelerators have been used to accelerate electron and positron particle beams with gradients that are orders of magnitude larger than those achieved in conventional accelerators. In addition to being accelerated by the plasma wakefield, the beam particles also experience strong transverse forces that may disrupt the beam quality. Hollow plasma channels have been proposed as a technique for generating accelerating fields without transverse forces. In this study, we demonstrate a method for creating an extended hollow plasma channel and measure the wakefields created by an ultrarelativistic positron beam as it propagates through the channel. The plasma channel ismore » created by directing a high-intensity laser pulse with a spatially modulated profile into lithium vapour, which results in an annular region of ionization. A peak decelerating field of 230 MeV m-1 is inferred from changes in the beam energy spectrum, in good agreement with theory and particle-in-cell simulations.« less

  11. Acceleration of positrons by a relativistic electron beam in the presence of quantum effects

    SciTech Connect (OSTI)

    Niknam, A. R.; Aki, H.; Khorashadizadeh, S. M.

    2013-09-15

    Using the quantum magnetohydrodynamic model and obtaining the dispersion relation of the Cherenkov and cyclotron waves, the acceleration of positrons by a relativistic electron beam is investigated. The Cherenkov and cyclotron acceleration mechanisms of positrons are compared together. It is shown that growth rate and, therefore, the acceleration of positrons can be increased in the presence of quantum effects.

  12. The ADAPT concept - an accelerator driven system for the rapid...

    Office of Scientific and Technical Information (OSTI)

    ADAPT employs a high current CW linear accelerator (linac) to generate neutrons in a leadD2O target. The neutrons are then absorbed in a surrounding subcritical (Keffapprox0.95) ...

  13. Organization of the 16th Advanced Accelerator Concepts (AAC)...

    Office of Scientific and Technical Information (OSTI)

    Essentially all we know today and will learn in the future about the fundamental nature of ... Over the last century, particle accelerators have changed the way we look at nature and ...

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

    ScienceCinema (OSTI)

    Andrei Seryi

    2010-01-08

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

  15. Beam loading in a laser-plasma accelerator using a near-hollow plasma channel

    SciTech Connect (OSTI)

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

    2013-12-15

    Beam loading in laser-plasma accelerators using a near-hollow plasma channel is examined in the linear wake regime. It is shown that, by properly shaping and phasing the witness particle beam, high-gradient acceleration can be achieved with high-efficiency, and without induced energy spread or emittance growth. Both electron and positron beams can be accelerated in this plasma channel geometry. Matched propagation of electron beams can be achieved by the focusing force provided by the channel density. For positron beams, matched propagation can be achieved in a hollow plasma channel with external focusing. The efficiency of energy transfer from the wake to a witness beam is calculated for single ultra-short bunches and bunch trains.

  16. Optics measurement and correction during beam acceleration in the Relativistic Heavy Ion Collider

    SciTech Connect (OSTI)

    Liu, C.; Marusic, A.; Minty, M.

    2014-09-09

    To minimize operational complexities, setup of collisions in high energy circular colliders typically involves acceleration with near constant β-functions followed by application of strong focusing quadrupoles at the interaction points (IPs) for the final beta-squeeze. At the Relativistic Heavy Ion Collider (RHIC) beam acceleration and optics squeeze are performed simultaneously. In the past, beam optics correction at RHIC has taken place at injection and at final energy with some interpolation of corrections into the acceleration cycle. Recent measurements of the beam optics during acceleration and squeeze have evidenced significant beta-beats which if corrected could minimize undesirable emittance dilutions and maximize the spin polarization of polarized proton beams by avoidance of higher-order multipole fields sampled by particles within the bunch. In this report the methodology now operational at RHIC for beam optics corrections during acceleration with simultaneous beta-squeeze will be presented together with measurements which conclusively demonstrate the superior beam control. As a valuable by-product, the corrections have minimized the beta-beat at the profile monitors so reducing the dominant error in and providing more precise measurements of the evolution of the beam emittances during acceleration.

  17. Report of the ICFA Beam Dynamics Workshop 'Accelerators for a Higgs

    Office of Scientific and Technical Information (OSTI)

    Factory: Linear Vs. Circular' (HF2012) (Conference) | SciTech Connect Conference: Report of the ICFA Beam Dynamics Workshop 'Accelerators for a Higgs Factory: Linear Vs. Circular' (HF2012) Citation Details In-Document Search Title: Report of the ICFA Beam Dynamics Workshop 'Accelerators for a Higgs Factory: Linear Vs. Circular' (HF2012) Authors: Blondel, Alain ; Chao, Alex ; /Geneva U., astr /SLAC ; Chou, Weiren ; /Fermilab ; Gao, Jie ; /Beijing, Inst. High Energy Phys. ; Schulte, Daniel ;

  18. Limiting electron beam current for cyclic induction acceleration in a constant guide field

    SciTech Connect (OSTI)

    Kanunnikov, V.N.

    1982-09-01

    Theoretical relations are derived for the limiting beam current in a cyclic induction accelerator (CIA) with a constant guide field. The calculations are in agreement with the available experimental data. It is shown that the limiting average beam current in a CIA is of the order of 100 microamperes, i.e., the level attained in microtrons and linear accelerators. The CIA may find industrial applications.

  19. Photoelectron linear accelerator for producing a low emittance polarized electron beam

    DOE Patents [OSTI]

    Yu, David U.; Clendenin, James E.; Kirby, Robert E.

    2004-06-01

    A photoelectron linear accelerator for producing a low emittance polarized electric beam. The accelerator includes a tube having an inner wall, the inner tube wall being coated by a getter material. A portable, or demountable, cathode plug is mounted within said tube, the surface of said cathode having a semiconductor material formed thereon.

  20. Electron-Beam Dynamics for an Advanced Flash-Radiography Accelerator

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

    Ekdahl, Carl

    2015-11-17

    Beam dynamics issues were assessed for a new linear induction electron accelerator being designed for multipulse flash radiography of large explosively driven hydrodynamic experiments. Special attention was paid to equilibrium beam transport, possible emittance growth, and beam stability. Especially problematic would be high-frequency beam instabilities that could blur individual radiographic source spots, low-frequency beam motion that could cause pulse-to-pulse spot displacement, and emittance growth that could enlarge the source spots. Furthermore, beam physics issues were examined through theoretical analysis and computer simulations, including particle-in-cell codes. Beam instabilities investigated included beam breakup, image displacement, diocotron, parametric envelope, ion hose, and themore » resistive wall instability. The beam corkscrew motion and emittance growth from beam mismatch were also studied. It was concluded that a beam with radiographic quality equivalent to the present accelerators at Los Alamos National Laboratory will result if the same engineering standards and construction details are upheld.« less

  1. Interactive visualization of particle beams for accelerator design

    SciTech Connect (OSTI)

    Wilson, Brett; Ma, Kwan-Liu; Qiang, Ji; Ryne, Robert

    2002-01-15

    We describe a hybrid data-representation and rendering technique for visualizing large-scale particle data generated from numerical modeling of beam dynamics. The basis of the technique is mixing volume rendering and point rendering according to particle density distribution, visibility, and the user's instruction. A hierarchical representation of the data is created on a parallel computer, allowing real-time partitioning into high-density areas for volume rendering, and low-density areas for point rendering. This allows the beam to be interactively visualized while preserving the fine structure usually visible only with slow point based rendering techniques.

  2. Simulation of quasimonoenergetic electron beams produced by colliding pulse wakefield acceleration

    SciTech Connect (OSTI)

    Davoine, X.; Lefebvre, E.; Lifschitz, A.

    2008-11-15

    The collision of two laser pulses can inject electrons into a wakefield accelerator, and has been found to produce stable and tunable quasimonoenergetic electron beams [J. Faure et al., Nature 444, 737 (2006)]. This colliding pulse scheme is studied here with 3D particle-in-cell simulations. The results are successfully compared with experimental data, showing the accuracy of the simulations. The involved mechanisms (laser propagation, wake inhibition, electron heating and trapping, beam loading) are presented in detail. We explain their interplay effects on the beam parameters. The experimental variations of beam charge and energy with collision position are explained.

  3. A 200 MHz 35 MW Multiple Beam Klystron for Accelerator Applications Final Report

    SciTech Connect (OSTI)

    R. Lawrence Ives; Michael Read; Patrick Ferguson; David Marsden

    2011-11-28

    Calabazas Creek Research, Inc. (CCR) performed initial development of a compact and reliable 35 MW, multiple beam klystron (MBK) at 200 MHz with a pulse length of 0.125 ms and a 30 Hz repetition rate. The device was targeted for acceleration and ionization cooling of a muon collider, but there are several other potential applications in this frequency range. The klystron uses multiple beams propagating in individual beam tunnels to reduce space charge and allow reduction in the accelerating voltage. This allows a significant reduction in length over a single beam source. More importantly this allows more efficient and less expensive power supplies. At 200 MHz, the interaction circuit for a single beam klystron would be more than six meters long to obtain 50% efficiency and 50 dB gain. This would require a beam voltage of approximately 400 kV and current of 251 A for a microperveance of 1.0. For an eight beam MBK with the same beam perveance, a three meter long interaction circuit achieves the same power and gain. Each beam operates at 142 kV and 70A. The Phase I demonstrated that this device could be fabricated with funding available in a Phase II program and could achieve the program specifications.

  4. Particle-in-cell/accelerator code for space-charge dominated beam simulation

    SciTech Connect (OSTI)

    2012-05-08

    Warp is a multidimensional discrete-particle beam simulation program designed to be applicable where the beam space-charge is non-negligible or dominant. It is being developed in a collaboration among LLNL, LBNL and the University of Maryland. It was originally designed and optimized for heave ion fusion accelerator physics studies, but has received use in a broader range of applications, including for example laser wakefield accelerators, e-cloud studies in high enery accelerators, particle traps and other areas. At present it incorporates 3-D, axisymmetric (r,z) planar (x-z) and transverse slice (x,y) descriptions, with both electrostatic and electro-magnetic fields, and a beam envelope model. The code is guilt atop the Python interpreter language.

  5. Particle-in-cell/accelerator code for space-charge dominated beam simulation

    Energy Science and Technology Software Center (OSTI)

    2012-05-08

    Warp is a multidimensional discrete-particle beam simulation program designed to be applicable where the beam space-charge is non-negligible or dominant. It is being developed in a collaboration among LLNL, LBNL and the University of Maryland. It was originally designed and optimized for heave ion fusion accelerator physics studies, but has received use in a broader range of applications, including for example laser wakefield accelerators, e-cloud studies in high enery accelerators, particle traps and other areas.more » At present it incorporates 3-D, axisymmetric (r,z) planar (x-z) and transverse slice (x,y) descriptions, with both electrostatic and electro-magnetic fields, and a beam envelope model. The code is guilt atop the Python interpreter language.« less

  6. Optimization of Drive-Bunch Current Profile for Enhanced Transformer Ratio in Beam-Driven Acceleration Techniques

    SciTech Connect (OSTI)

    Lemery, F.; Mihalcea, D.; Prokop, C.R.; Piot, P.; /Northern Illinois U. /Fermilab

    2012-07-08

    In recent years, wakefield acceleration has gained attention due to its high acceleration gradients and cost effectiveness. In beam-driven wakefield acceleration, a critical parameter to optimize is the transformer ratio. It has been shown that current shaping of electron beams allows for enhanced (> 2) transformer ratios. In this paper we present the optimization of the pulse shape of the drive bunch for dielectric-wakefield acceleration.

  7. Multiple quasi-monoenergetic electron beams from laser-wakefield acceleration with spatially structured laser pulse

    SciTech Connect (OSTI)

    Ma, Y.; Li, M. H.; Li, Y. F.; Wang, J. G.; Tao, M. Z.; Han, Y. J.; Zhao, J. R.; Huang, K.; Yan, W. C.; Ma, J. L.; Li, Y. T.; Chen, L. M.; Li, D. Z.; Chen, Z. Y.; Sheng, Z. M.; Zhang, J.

    2015-08-15

    By adjusting the focus geometry of a spatially structured laser pulse, single, double, and treble quasi-monoenergetic electron beams were generated, respectively, in laser-wakefield acceleration. Single electron beam was produced as focusing the laser pulse to a single spot. While focusing the laser pulse to two spots that are approximately equal in energy and size and intense enough to form their own filaments, two electron beams were produced. Moreover, with a proper distance between those two focal spots, three electron beams emerged with a certain probability owing to the superposition of the diffractions of those two spots. The energy spectra of the multiple electron beams are quasi-monoenergetic, which are different from that of the large energy spread beams produced due to the longitudinal multiple-injection in the single bubble.

  8. Optimization and beam control in large-emittance accelerators: Neutrino factories;

    SciTech Connect (OSTI)

    Carol Johnstone

    2004-08-23

    Schemes for intense sources of high-energy muons require collection, rf capture, and transport of particle beams with unprecedented emittances, both longitudinally and transversely. These large emittances must be reduced or ''cooled'' both in size and in energy spread before the muons can be efficiently accelerated. Therefore, formation of muon beams sufficiently intense to drive a Neutrino Factory or Muon Collider requires multi-stage preparation. Further, because of the large beam phase space which must be successfully controlled, accelerated, and transported, the major stages that comprise such a facility: proton driver, production, capture, phase rotation, cooling, acceleration, and storage are complex and strongly interlinked. Each of the stages must be consecutively matched and simultaneously optimized with upstream and downstream systems, meeting challenges not only technically in the optics and component design, but also in the modeling of both new and extended components. One design for transverse cooling, for example, employs meter-diameter solenoids to maintain strong focusing--300-500 mr beam divergences--across ultra-large momentum ranges, {ge} {+-}20% {delta}p/p, defying conventional approximations to the dynamics and field representation. To now, the interplay of the different systems and staging strategies has not been formally addressed. This work discusses two basic, but different approaches to a Neutrino Factory and how the staging strategy depends on beam parameters and method of acceleration.

  9. Induction accelerators and free-electron lasers at LLNL: Beam Research Program

    SciTech Connect (OSTI)

    Briggs, R.J.

    1989-02-15

    Linear induction accelerators have been developed to produce pulses of charged particles at voltages exceeding the capabilities of single-stage, diode-type accelerators and at currents too high rf accelerators. In principle, one can accelerate charged particles to arbitrarily high voltages using a multistage induction machine. The advent of magnetic pulse power systems makes sustained operation at high repetition rates practical, and high-average-power capability is very likely to open up many new applications of induction machines. In Part A of this paper, we survey the US induction linac technology, emphasizing electron machines. We also give a simplified description of how induction machines couple energy to the electron beam to illustrate many general issues that designers of high-brightness and high-average-power induction linacs must consider. We give an example of the application of induction accelerator technology to the relativistic klystron, a power source for high-gradient accelerators. In Part B we address the application of LIAs to free-electron lasers. The multikiloampere peak currents available from linear induction accelerators make high-gain, free-electron laser amplifier configurations feasible. High extraction efficiencies in a single mass of the electron beam are possible if the wiggler parameters are appropriately ''tapered'', as recently demonstrated at millimeter wavelengths on the 4-MeV ELF facility. Key issues involved in extending the technology to shorter wavelengths and higher average powers are described. Current FEL experiments at LLNL are discussed. 5 refs., 16 figs.

  10. Long pulse acceleration of MeV class high power density negative H{sup −} ion beam for ITER

    SciTech Connect (OSTI)

    Umeda, N. Kojima, A.; Kashiwagi, M.; Tobari, H.; Hiratsuka, J.; Watanabe, K.; Dairaku, M.; Yamanaka, H.; Hanada, M.

    2015-04-08

    R and D of high power density negative ion beam acceleration has been carried out at MeV test facility in JAEA to realize ITER neutral beam accelerator. The main target is H{sup −} ion beam acceleration up to 1 MeV with 200 A/m{sup 2} for 60 s whose pulse length is the present facility limit. For long pulse acceleration at high power density, new extraction grid (EXG) has been developed with high cooling capability, which electron suppression magnet is placed under cooling channel similar to ITER. In addition, aperture size of electron suppression grid (ESG) is enlarged from 14 mm to 16 mm to reduce direct interception on the ESG and emission of secondary electron which leads to high heat load on the upstream acceleration grid. By enlarging ESG aperture, beam current increased 10 % at high current beam and total acceleration grid heat load reduced from 13 % to 10 % of input power at long pulse beam. In addition, heat load by back stream positive ion into the EXG is measured for the first time and is estimated as 0.3 % of beam power, while heat load by back stream ion into the source chamber is estimated as 3.5 ~ 4.0 % of beam power. Beam acceleration up to 60 s which is the facility limit, has achieved at 683 keV, 100 A/m{sup 2} of negative ion beam, whose energy density increases two orders of magnitude since 2011.

  11. Correlation of Beam Parameters to Decelerating Gradient in the E-167 Plasma Wakefield Acceleration Experiment

    SciTech Connect (OSTI)

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

    2007-06-27

    Recent experiments at SLAC have shown that high gradient acceleration of electrons is achievable in meter scale plasmas [1,2]. Results from these experiments show that the wakefield is sensitive to parameters in the electron beam which drives it. In the experiment the bunch length and beam waist location were varied systematically at constant charge. Here we investigate the correlation of peak beam current to the decelerating gradient. Limits on the transformer ratio will also be discussed. The results are compared to simulation.

  12. Collimated electron beam accelerated at 12 kV from a Penning discharge

    SciTech Connect (OSTI)

    Toader, D.; Oane, M.; Ticoş, C. M.

    2015-01-15

    A pulsed electron beam accelerated at 12 kV with a duration of 40 μs per pulse is obtained from a Penning discharge with a hollow anode and two cathodes. The electrons are extracted through a hole in one of the cathodes and focused by a pair of coils. The electron beam has a diameter of a few mm in the cross section, while the beam current reaches peak values of 400 mA, depending on the magnetic field inside the focussing coils. This relatively inexpensive and compact device is suitable for the irradiation of small material samples placed in high vacuum.

  13. Transverse Beam Emittance Measurements of a 16 MeV Linac at the Idaho Accelerator Center

    SciTech Connect (OSTI)

    S. Setiniyaz, T.A. Forest, K. Chouffani, Y. Kim, A. Freyberger

    2012-07-01

    A beam emittance measurement of the 16 MeV S-band High Repetition Rate Linac (HRRL) was performed at Idaho State University's Idaho Accelerator Center (IAC). The HRRL linac structure was upgraded beyond the capabilities of a typical medical linac so it can achieve a repetition rate of 1 kHz. Measurements of the HRRL transverse beam emittance are underway that will be used to optimize the production of positrons using HRRL's intense electron beam on a tungsten converter. In this paper, we describe a beam imaging system using on an OTR screen and a digital CCD camera, a MATLAB tool to extract beamsize and emittance, detailed measurement procedures, and the measured transverse emittances for an arbitrary beam energy of 15 MeV.

  14. Intrinsic beam emittance of laser-accelerated electrons measured by x-ray spectroscopic imaging

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

    Golovin, G.; Banerjee, S.; Liu, C.; Chen, S.; Zhang, J.; Zhao, B.; Zhang, P.; Veale, M.; Wilson, M.; Seller, P.; et al

    2016-04-19

    Here, the recent combination of ultra-intense lasers and laser-accelerated electron beams is enabling the development of a new generation of compact x-ray light sources, the coherence of which depends directly on electron beam emittance. Although the emittance of accelerated electron beams can be low, it can grow due to the effects of space charge during free-space propagation. Direct experimental measurement of this important property is complicated by micron-scale beam sizes, and the presence of intense fields at the location where space charge acts. Reported here is a novel, non-destructive, single-shot method that overcame this problem. It employed an intense lasermore » probe pulse, and spectroscopic imaging of the inverse-Compton scattered x-rays, allowing measurement of an ultra-low value for the normalized transverse emittance, 0.15 (±0.06) π mm mrad, as well as study of its subsequent growth upon exiting the accelerator. The technique and results are critical for designing multi-stage laser-wakefield accelerators, and generating high-brightness, spatially coherent x-rays.« less

  15. Artificial intelligence research in particle accelerator control systems for beam line tuning

    SciTech Connect (OSTI)

    Pieck, Martin

    2008-01-01

    Tuning particle accelerators is time consuming and expensive, with a number of inherently non-linear interactions between system components. Conventional control methods have not been successful in this domain and the result is constant and expensive monitoring of the systems by human operators. This is particularly true for the start-up and conditioning phase after a maintenance period or an unexpected fault. In turn, this often requires a step-by-step restart of the accelerator. Surprisingly few attempts have been made to apply intelligent accelerator control techniques to help with beam tuning, fault detection, and fault recovery problems. The reason for that might be that accelerator facilities are rare and difficult to understand systems that require detailed expert knowledge about the underlying physics as well as months if not years of experience to understand the relationship between individual components, particularly if they are geographically disjoint. This paper will give an overview about the research effort in the accelerator community that has been dedicated to the use of artificial intelligence methods for accelerator beam line tuning.

  16. Mechanical Design of a High Energy Beam Absorber for the Advanced Superconducting Test Accelerator (ASTA) at Fermilab

    SciTech Connect (OSTI)

    Baffes, C.; Church, M.; Leibfritz, J.; Oplt, S.; Rakhno, I.; /Fermilab

    2012-05-10

    A high energy beam absorber has been built for the Advanced Superconducting Test Accelerator (ASTA) at Fermilab. In the facility's initial configuration, an electron beam will be accelerated through 3 TTF-type or ILC-type SRF cryomodules to an energy of 750MeV. The electron beam will be directed to one of multiple downstream experimental and diagnostic beam lines and then deposited in one of two beam absorbers. The facility is designed to accommodate up to 6 cryomodules, which would produce a 75kW beam at 1.5GeV; this is the driving design condition for the beam absorbers. The beam absorbers consist of water-cooled graphite, aluminum and copper layers contained in a helium-filled enclosure. This paper describes the mechanical implementation of the beam absorbers, with a focus on thermal design and analysis. The potential for radiation-induced degradation of the graphite is discussed.

  17. Beam extraction from TeV accelerators using channeling in bent crystals

    SciTech Connect (OSTI)

    Carrigan, R.A. Jr.; Toohig, T.E.; Tsyganov, E.N.; Superconducting Super Collider Lab., Dallas, TX; Joint Inst. for Nuclear Research, Dubna )

    1989-08-01

    Bent crystal channeling offers an interesting alternative for beam extraction from trans-GeV accelerators. Conventional extraction employs resonant beam blow-up coupled with electromagnetic beam deflecting channels. It is limited by the length of the available accelerator straight section. Channeling crystals require much less space. A five-step approach to applying crystal extraction in the Superconducting Super Collider (SSC) is discussed. Two steps, extraction from the 8 GeV Dubna Synchrophasotron and the 76 GeV Serpukhov accelerator, have occurred. The next possibility is extraction from a multi-hundred GeV superconducting accelerator. In the nineties the program could continue at UNK (3 TeV) and culminate at the TeV SSC. The possibilities and limitations of crystal extraction are reviewed. More information is needed on dechanneling in bent crystals including the effects of dislocations at TeV energies. Long, dislocation-free'' crystals are required. A more thorough understanding of the theory of crystal extraction is also desirable. 12 refs.

  18. High-intensity ion sources for accelerators with emphasis on H-beam formation and transport

    SciTech Connect (OSTI)

    Keller, Roderich

    2009-01-01

    This paper lays out the fundamental working principles of a variety of high-current ion sources for accelerators in a tutorial manner, and gives examples of specific source types such as d. c. discharge- and rf-driven multicusp sources. Penning-type and ECR-based sources while discussing those principles, pointing out general performance limits as well as the performance parameters of specific sources. Laser-based, two-chamber-. and surface-ionization sources are briefly mentioned. Main aspects of this review are particle feed. ionization mechanism, beam formation and beam transport. Issues seen with beam formation and low-energy transport of negative hydrogen-ion beams are treated in detail.

  19. First Beam Waist Measurements in the Final Focus Beam Line at the KEK Accelerator Test Facility

    SciTech Connect (OSTI)

    Bai, Sha; Aryshev, Alexander; Bambade, Philip; McCormick, Doug; Bolzon, Benoit; Gao, Jie; Tauchi, Toshiaki; Zhou, Feng; /SLAC

    2012-06-22

    The ATF2 project is the final focus system prototype for the ILC and CLIC linear collider projects, with a purpose to reach a 37 nm vertical beam size at the interaction point using compact optics based on a novel scheme of local chromaticity correction. Construction of all components and installation were completed at the end of 2008. An initial commissioning phase followed in 2009, using larger than nominal {beta} functions at the interaction point, corresponding to reduced demagnification factors in comparison to the design, to limit effects from higher-order optical aberrations and hence simplify beam tuning procedures while key instrumentation was being tested and calibrated. In this paper, first measurements of dispersion and Twiss parameters are presented based on scanning the beam during this period with a set of tungsten wires located just behind the interaction point, using two complementary analysis methods.

  20. The LACARA Vacuum Laser Accelerator Experiment: Beam Positioning and Alignment in a Strong Magnetic Field

    SciTech Connect (OSTI)

    Shchelkunov, Sergey V.; Marshall, T. C.; Hirshfield, J. L.; Wang, Changbiao; LaPointe, M. A.

    2006-11-27

    LACARA (laser cyclotron auto-resonance accelerator) is a vacuum laser accelerator of electrons that is under construction at the Accelerator Test Facility (ATF), Brookhaven National Laboratory. It is expected that the experiment will be assembled by September 2006; this paper presents progress towards this goal. According to numerical studies, as an electron bunch moves along the LACARA solenoidal magnetic field ({approx}5.2 T, length {approx}1 m), it will be accelerated from 50 to {approx}75 MeV by interacting with a 0.8 TW Gaussian-mode circularly polarized optical pulse provided by the ATF CO2 10.6{mu}m laser system. The LACARA laser transport optics must handle 10 J and be capable of forming a Gaussian beam inside the solenoid with a 1.4 mm waist and a Rayleigh range of 60 cm. The electron optics must transport a bunch having input emittance of 0.015 mm-mrad and 100 {mu}m waist through the magnet. Precision alignment between the electron beam and the solenoid magnetic axis is required, and a method to achieve this is described in detail. Emittance- filtering may be necessary to yield an accelerated bunch having a narrow ({approx}1%) energy-spread.

  1. 9 GeV energy gain in a beam-driven plasma wakefield accelerator

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

    Litos, M.; Adli, E.; Allen, J. M.; An, W.; Clarke, C. I.; Corde, S.; Clayton, C. E.; Frederico, J.; Gessner, S. J.; Green, S. Z.; et al

    2016-02-15

    An electron beam has gained a maximum energy of 9 GeV per particle in a 1.3 m-long electron beam-driven plasma wakefield accelerator. The amount of charge accelerated in the spectral peak was 28.3 pC, and the root-mean-square energy spread was 5.0%. The mean accelerated charge and energy gain per particle of the 215 shot data set was 115 pC and 5.3 GeV, respectively, corresponding to an acceleration gradient of 4.0 GeV m-1 at the spectral peak. Moreover, the mean energy spread of the data set was 5.1%. Our results are consistent with the extrapolation of the previously reported energy gainmore » results using a shorter, 36 cm-long plasma source to within 10%, evincing a non-evolving wake structure that can propagate distances of over a meter in length. Wake-loading effects were evident in the data through strong dependencies observed between various spectral properties and the amount of accelerated charge.« less

  2. Analysis of longitudinal bunching in an FEL driven two-beam accelerator

    SciTech Connect (OSTI)

    Lidia, S.; Gardelle, J.; Lefevre, T.; Donohue, J.T.; Gouard, P.; Rullier, J.L.; Vermare, C.

    2000-08-01

    Recent experiments have explored the use of a free-electron laser (FEL) as a buncher for a microwave two-beam accelerator, and the subsequent driving of a standing-wave rf output cavity. Here the authors present a deeper analysis of the longitudinal dynamics of the electron bunches as they are transported from the end of the FEL and through the output cavity. In particular, the authors examine the effect of the transport region and cavity aperture to filter the bunched portion of the beam.

  3. Electron beam dynamics in the long-pulse, high-current DARHT-II linear induction accelerator

    SciTech Connect (OSTI)

    Ekdahl, Carl A; Abeyta, Epifanio O; Aragon, Paul; Archuleta, Rita; Cook, Gerald; Dalmas, Dale; Esquibel, Kevin; Gallegos, Robert A; Garnett, Robert; Harrison, James F; Johnson, Jeffrey B; Jacquez, Edward B; Mccuistian, Brian T; Montoya, Nicholas A; Nath, Subrato; Nielsen, Kurt; Oro, David; Prichard, Benjamin; Rowton, Lawrence; Sanchez, Manolito; Scarpetti, Raymond; Schauer, Martin M; Seitz, Gerald; Schulze, Martin; Bender, Howard A; Broste, William B; Carlson, Carl A; Frayer, Daniel K; Johnson, Douglas E; Tom, C Y; Williams, John; Hughes, Thomas; Anaya, Richard; Caporaso, George; Chambers, Frank; Chen, Yu - Jiuan; Falabella, Steve; Guethlein, Gary; Raymond, Brett; Richardson, Roger; Trainham, C; Weir, John; Genoni, Thomas; Toma, Carsten

    2009-01-01

    The DARHT-II linear induction accelerator (LIA) now accelerates 2-kA electron beams to more than 17 MeV. This LIA is unique in that the accelerated current pulse width is greater than 2 microseconds. This pulse has a flat-top region where the final electron kinetic energy varies by less than 1% for more than 1.5 microseconds. The long risetime of the 6-cell injector current pulse is 0.5 {micro}s, which can be scraped off in a beam-head cleanup zone before entering the 68-cell main accelerator. We discuss our experience with tuning this novel accelerator; and present data for the resulting beam transport and dynamics. We also present beam stability data, and relate these to previous stability experiments at lower current and energy.

  4. Evaluation of Negative-Ion-Beam Driver Concepts for Heavy Ion Fusion

    SciTech Connect (OSTI)

    Grisham, Larry R.

    2003-03-15

    The feasibility of producing and using atomically neutral heavy ion beams produced from negative ions as drivers for an inertial confinement fusion reactor is evaluated. Bromine and iodine appear to be the most attractive elements for the driver beams. Fluorine and chlorine appear to be the most appropriate feedstocks for initial tests of extractable negative-ion current densities. With regard to ion sources, photodetachment neutralizers, and vacuum requirements for accelerators and beam transport, this approach appears feasible within existing technology, and the vacuum requirements are essentially identical to those for positive-ion drivers except in the target chamber. The principal constraint is that this approach requires harder vacuums in the target chamber than do space-charge-neutralized positive-ion drivers. With realistic (but perhaps pessimistic) estimates of the total ionization cross section, limiting the ionization of a neutral beam to <5% while traversing a 3-m path would require a chamber pressure of no more than 1.3 x 10{sup -5} torr. However, it appears that substantial improvements in the beam spot size on target might be achieved at pressures a factor of 10 or more higher than this. Alternatively, even at still higher chamber pressures that would strongly ionize atomically neutral beams, the negative-ion approach may still have significant appeal, since it precludes the possibly challenging problem of electron contamination of a positive-ion beam during acceleration, drift compression, and focusing.

  5. SU-E-T-52: Beam Data Comparison for 20 Linear Accelerators in One Network

    SciTech Connect (OSTI)

    LoSasso, T; Lim, S; Tang, G; Chan, M; Li, J; Obcemea, C; Song, Y; Ma, R; Yang, G; Xiong, W; Huang, D; Burman, C; Mechalakos, J; Hunt, M

    2014-06-01

    Purpose: To compare photon beam data for the 20 Varian linear accelerators (TrueBeam, iX, and EX models) in use at five centers in the same network with the intent to model with one set of beam data in Eclipsec. Methods: Varian linear accelerators, TrueBeam (3), 21 EX, iX, and Trilogy (14), and 6 EX (3), installed between 1999 and 2014 have their 6 MV and 15 MV x-ray beams reevaluated. Full commissioning, including output factors (St), percent depth doses (PDD), and off-axis profiles, was recently performed for a TrueBeam with a cc04 ion chamber in an IBA Blue phantom. Similarly, a subset of beam data for each of the other accelerators was measured recently as follows: for 33, 1010, and 3030 cm{sup 2} field sizes, flatness and penumbra (8020%) were measured at dmax and 10 cm depths, PDD were measured at 10 and 20 cm depths, and St were measured at 5 cm depth. Measurement results for all machines were compared. Results: For 15 high-energy (6 and 15 MV) and 3 low-energy machines (6MV only): 1) PDD agreed within 1.4% at 10 and 20 cm depths; 2) penumbra agreed within 1.0 mm at dmax and 10 cm depths; 3) flatness was within 1.3% at dmax and 10 cm depths; and 4) with exception of the three low energy machines, output factors were within 1.1% and 0.5% for 33 and 3030 cm{sup 2}, respectively. Measurement uncertainty, not quantified here, accounts for some of these differences. Conclusion: Measured beam data from 15 high-energy Varian linacs are consistent enough that they can be classified using one beam data set in Eclipse. Two additional high-energy machines are removed from this group until their data are further confirmed. Three low-energy machines will be in a separate class based upon differences in output factors (St)

  6. Reduction of the beam breakup mode Q values in the ETA/ATA Accelerating Cells

    SciTech Connect (OSTI)

    Birx, D.L.

    1980-05-20

    Earlier Microwave Measurements of the ETA Accelerating Cells has uncovered eleven resonances in the frequency range of 0 > 850 MHz. The Q values of these modes ranged from 14 to 70. A three phase program directed at substantially reducing these Q values is reported. In particular the dampening methods described below resulted in a decrease of Q value from 40 to 5 for the beam breakup mode (TM/sub 110/) with a corresponding reduction for most of the other cavity modes.

  7. Creating a Well-focused Laser-accelerated Proton Beam as a Driver for

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

    Proton Fast Ignition | U.S. DOE Office of Science (SC) Creating a Well-focused Laser-accelerated Proton Beam as a Driver for Proton Fast Ignition Fusion Energy Sciences (FES) FES Home About Research Facilities Science Highlights Benefits of FES Funding Opportunities Fusion Energy Sciences Advisory Committee (FESAC) Community Resources Contact Information Fusion Energy Sciences U.S. Department of Energy SC-24/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301)

  8. Early Commissioning Experience and Future Plans for the 12 GeV Continuous Electron Beam Accelerator Facility

    SciTech Connect (OSTI)

    Spata, Michael F.

    2014-12-01

    Jefferson Lab has recently completed the accelerator portion of the 12 GeV Upgrade for the Continuous Electron Beam Accelerator Facility. All 52 SRF cryomodules have been commissioned and operated with beam. The initial beam transport goals of demonstrating 2.2 GeV per pass, greater than 6 GeV in 3 passes to an existing experimental facility and greater than 10 GeV in 5-1/2 passes have all been accomplished. These results along with future plans to commission the remaining beamlines and to increase the performance of the accelerator to achieve reliable, robust and efficient operations at 12 GeV are presented.

  9. The energy transfer in the TEMP-4M pulsed ion beam accelerator

    SciTech Connect (OSTI)

    Isakova, Y. I.; Pushkarev, A. I.; Khaylov, I. P.

    2013-07-15

    The results of a study of the energy transfer in the TEMP-4M pulsed ion beam accelerator are presented. The energy transfer efficiency in the Blumlein and a self-magnetically insulated ion diode was analyzed. Optimization of the design of the accelerator allows for 85% of energy transferred from Blumlein to the diode (including after-pulses), which indicates that the energy loss in Blumlein and spark gaps is insignificant and not exceeds 10%12%. Most losses occur in the diode. The efficiency of energy supplied to the diode to the energy of accelerated ions is 8%9% for a planar strip self-magnetic MID, 12%15% for focusing diode and 20% for a spiral self-magnetic MID.

  10. Microwave Ion Source and Beam Injection for an Accelerator-drivenNeutron Source

    SciTech Connect (OSTI)

    Vainionpaa, J.H.; Gough, R.; Hoff, M.; Kwan, J.W.; Ludewigt,B.A.; Regis, M.J.; Wallig, J.G.; Wells, R.

    2007-02-15

    An over-dense microwave driven ion source capable ofproducing deuterium (or hydrogen) beams at 100-200 mA/cm2 and with atomicfraction>90 percent was designed and tested with an electrostaticlow energy beam transport section (LEBT). This ion source wasincorporatedinto the design of an Accelerator Driven Neutron Source(ADNS). The other key components in the ADNS include a 6 MeV RFQaccelerator, a beam bending and scanning system, and a deuterium gastarget. In this design a 40 mA D+ beam is produced from a 6 mm diameteraperture using a 60 kV extraction voltage. The LEBT section consists of 5electrodes arranged to form 2 Einzel lenses that focus the beam into theRFQ entrance. To create the ECR condition, 2 induction coils are used tocreate ~; 875 Gauss on axis inside the source chamber. To prevent HVbreakdown in the LEBT a magnetic field clamp is necessary to minimize thefield in this region. Matching of the microwave power from the waveguideto the plasma is done by an autotuner. We observed significantimprovement of the beam quality after installing a boron nitride linerinside the ion source. The measured emittance data are compared withPBGUNS simulations.

  11. AGS SUPER NEUTRINO BEAM FACILITY ACCELERATOR AND TARGET SYSTEM DESIGN (NEUTRINO WORKING GROUP REPORT-II).

    SciTech Connect (OSTI)

    DIWAN,M.; MARCIANO,W.; WENG,W.; RAPARIA,D.

    2003-04-21

    This document describes the design of the accelerator and target systems for the AGS Super Neutrino Beam Facility. Under the direction of the Associate Laboratory Director Tom Kirk, BNL has established a Neutrino Working Group to explore the scientific case and facility requirements for a very long baseline neutrino experiment. Results of a study of the physics merit and detector performance was published in BNL-69395 in October 2002, where it was shown that a wide-band neutrino beam generated by a 1 MW proton beam from the AGS, coupled with a half megaton water Cerenkov detector located deep underground in the former Homestake mine in South Dakota would be able to measure the complete set of neutrino oscillation parameters: (1) precise determination of the oscillation parameters {Delta}m{sub 32}{sup 2} and sin{sup 2} 2{theta}{sub 32}; (2) detection of the oscillation of {nu}{sub {mu}}-{nu}{sub e} and measurement of sin{sup 2} 2{theta}{sub 13}; (3) measurement of {Delta}m{sub 21}{sup 2} sin 2{theta}{sub 12} in a {nu}{sub {mu}} {yields} {nu}{sub e} appearance mode, independent of the value of {theta}{sub 13}; (4) verification of matter enhancement and the sign of {Delta}m{sub 32}{sup 2}; and (5) determination of the CP-violation parameter {delta}{sub CP} in the neutrino sector. This report details the performance requirements and conceptual design of the accelerator and the target systems for the production of a neutrino beam by a 1.0 MW proton beam from the AGS. The major components of this facility include a new 1.2 GeV superconducting linac, ramping the AGS at 2.5 Hz, and the new target station for 1.0 MW beam. It also calls for moderate increase, about 30%, of the AGS intensity per pulse. Special care is taken to account for all sources of proton beam loss plus shielding and collimation of stray beam halo particles to ensure equipment reliability and personal safety. A preliminary cost estimate and schedule for the accelerator upgrade and target system are also

  12. Electron acceleration by a tightly focused Hermite-Gaussian beam: higher-order corrections

    SciTech Connect (OSTI)

    Zhao Zhiguo; Yang Dangxiao; Lue Baida

    2008-03-15

    Taking the TEM{sub 1,0}-mode Hermite-Gaussian (H-G) beam as a numerical calculation example, and based on the method of the perturbation series expansion, the higher-order field corrections of H-G beams are derived and used to study the electron acceleration by a tightly focused H-G beam in vacuum. For the case of the off-axis injection the field corrections to the terms of order f{sup 3} (f=1/kw{sub 0}, k and w{sub 0} being the wavenumber and waist width, respectively) are considered, and for the case of the on-axis injection the contributions of the terms of higher orders are negligible. By a suitable optimization of injection parameters the energy gain in the giga-electron-volt regime can be achieved.

  13. Evaluation of Negative-Ion-Beam Driver Concepts for Heavy Ion Fusion

    SciTech Connect (OSTI)

    Larry R. Grisham

    2002-01-14

    We evaluate the feasibility of producing and using atomically neutral heavy ion beams produced from negative ions as drivers for an inertial confinement fusion reactor. Bromine and iodine appear to be the most attractive elements for the driver beams. Fluorine and chlorine appear to be the most appropriate feedstocks for initial tests of extractable negative ion current densities. With regards to ion sources, photodetachment neutralizers, and vacuum requirements for accelerators and beam transport, this approach appears feasible within existing technology, and the vacuum requirements are essentially identical to those for positive ion drivers except in the target chamber. The principal constraint is that this approach requires harder vacuums in the target chamber than do space-charge-neutralized positive ion drivers. With realistic (but perhaps pessimistic) estimates of the total ionization cross section, limiting the ionization of a neutral beam to less than 5% while traversing a four -meter path would require a chamber pressure of no more than 5 x 10{sup -5} torr. Alternatively, even at chamber pressures that are too high to allow propagation of atomically neutral beams, the negative ion approach may still have appeal, since it precludes the possibly serious problem of electron contamination of a positive ion beam during acceleration, drift compression, and focusing.

  14. Design and construction of an optimized neutron beam shaping assembly for Boron Neutron Capture Therapy at the Tandar accelerator

    SciTech Connect (OSTI)

    Burlon, A.; Kreiner, A. J.; Valda, A. A.; Somacal, H.; Minsky, D. M.

    2007-02-12

    In this work we present an optimized neutron beam shaping assembly for epithermal Accelerator-Based Boron Neutron Capture Therapy (AB-BNCT) and discuss the simulations leading to its design.

  15. First Beam and High-Gradient Cryomodule Commissioning Results of the Advanced Superconducting Test Accelerator at Fermilab

    SciTech Connect (OSTI)

    Crawford, Darren; et al.

    2015-06-01

    The advanced superconducting test accelerator at Fermilab has accelerated electrons to 20 MeV and, separately, the International Linear Collider (ILC) style 8-cavity cryomodule has achieved the ILC performance milestone of 31.5 MV/m per cavity. When fully completed, the accelerator will consist of a photoinjector, one ILC-type cryomodule, multiple accelerator R&D beamlines, and a downstream beamline to inject 300 MeV electrons into the Integrable Optics Test Accelerator (IOTA). We report on the results of first beam, the achievement of our cryomodule to ILC gradient specifications, and near-term future plans for the facility.

  16. Technical Challenges and Scientific Payoffs of Muon BeamAccelerators for Particle Physics

    SciTech Connect (OSTI)

    Zisman, Michael S.

    2007-09-25

    Historically, progress in particle physics has largely beendetermined by development of more capable particle accelerators. Thistrend continues today with the recent advent of high-luminosityelectron-positron colliders at KEK and SLAC operating as "B factories,"the imminent commissioning of the Large Hadron Collider at CERN, and theworldwide development effort toward the International Linear Collider.Looking to the future, one of the most promising approaches is thedevelopment of muon-beam accelerators. Such machines have very highscientific potential, and would substantially advance thestate-of-the-art in accelerator design. A 20-50 GeV muon storage ringcould serve as a copious source of well-characterized electron neutrinosor antineutrinos (a Neutrino Factory), providing beams aimed at detectorslocated 3000-7500 km from the ring. Such long baseline experiments areexpected to be able to observe and characterize the phenomenon ofcharge-conjugation-parity (CP) violation in the lepton sector, and thusprovide an answer to one of the most fundamental questions in science,namely, why the matter-dominated universe in which we reside exists atall. By accelerating muons to even higher energies of several TeV, we canenvision a Muon Collider. In contrast with composite particles likeprotons, muons are point particles. This means that the full collisionenergy is available to create new particles. A Muon Collider has roughlyten times the energy reach of a proton collider at the same collisionenergy, and has a much smaller footprint. Indeed, an energy frontier MuonCollider could fit on the site of an existing laboratory, such asFermilab or BNL. The challenges of muon-beam accelerators are related tothe facts that i) muons are produced as a tertiary beam, with very large6D phase space, and ii) muons are unstable, with a lifetime at rest ofonly 2 microseconds. How these challenges are accommodated in theaccelerator design will be described. Both a Neutrino Factory and a Muon

  17. Beam Dynamics Studies and the Design, Fabrication and Testing of Superconducting Radiofrequency Cavity for High Intensity Proton Accelerator

    SciTech Connect (OSTI)

    Saini, Arun

    2012-03-01

    The application horizon of particle accelerators has been widening significantly in recent decades. Where large accelerators have traditionally been the tools of the trade for high-energy nuclear and particle physics, applications in the last decade have grown to include large-scale accelerators like synchrotron light sources and spallation neutron sources. Applications like generation of rare isotopes, transmutation of nuclear reactor waste, sub-critical nuclear power, generation of neutrino beams etc. are next area of investigation for accelerator scientific community all over the world. Such applications require high beam power in the range of few mega-watts (MW). One such high intensity proton beam facility is proposed at Fermilab, Batavia, US, named as Project-X. Project-X facility is based on H- linear accelerator (linac), which will operate in continuous wave (CW) mode and accelerate H- ion beam with average current of 1 mA from kinetic energy of 2.5 MeV to 3 GeV to deliver 3MW beam power. One of the most challenging tasks of the Project-X facility is to have a robust design of the CW linac which can provide high quality beam to several experiments simultaneously. Hence a careful design of linac is important to achieve this objective.

  18. A nuclear physics program at the Rare Isotope Beams Accelerator Facility in Korea

    SciTech Connect (OSTI)

    Moon, Chang-Bum

    2014-04-15

    This paper outlines the new physics possibilities that fall within the field of nuclear structure and astrophysics based on experiments with radioactive ion beams at the future Rare Isotope Beams Accelerator facility in Korea. This ambitious multi-beam facility has both an Isotope Separation On Line (ISOL) and fragmentation capability to produce rare isotopes beams (RIBs) and will be capable of producing and accelerating beams of wide range mass of nuclides with energies of a few to hundreds MeV per nucleon. The large dynamic range of reaccelerated RIBs will allow the optimization in each nuclear reaction case with respect to cross section and channel opening. The low energy RIBs around Coulomb barrier offer nuclear reactions such as elastic resonance scatterings, one or two particle transfers, Coulomb multiple-excitations, fusion-evaporations, and direct capture reactions for the study of the very neutron-rich and proton-rich nuclides. In contrast, the high energy RIBs produced by in-flight fragmentation with reaccelerated ions from the ISOL enable to explore the study of neutron drip lines in intermediate mass regions. The proposed studies aim at investigating the exotic nuclei near and beyond the nucleon drip lines, and to explore how nuclear many-body systems change in such extreme regions by addressing the following topics: the evolution of shell structure in areas of extreme proton to neutron imbalance; the study of the weak interaction in exotic decay schemes such as beta-delayed two-neutron or two-proton emission; the change of isospin symmetry in isobaric mirror nuclei at the drip lines; two protons or two neutrons radioactivity beyond the drip lines; the role of the continuum states including resonant states above the particle-decay threshold in exotic nuclei; and the effects of nuclear reaction rates triggered by the unbound proton-rich nuclei on nuclear astrophysical processes.

  19. Simulation of direct plasma injection for laser ion beam acceleration with a radio frequency quadrupole

    SciTech Connect (OSTI)

    Jin, Q. Y.; Li, Zh. M.; Liu, W.; Zhao, H. Y. Zhang, J. J.; Sha, Sh.; Zhang, Zh. L.; Zhang, X. Zh.; Sun, L. T.; Zhao, H. W.

    2014-07-15

    The direct plasma injection scheme (DPIS) has been being studied at Institute of Modern Physics since several years ago. A C{sup 6+} beam with peak current of 13 mA, energy of 593 keV/u has been successfully achieved after acceleration with DPIS method. To understand the process of DPIS, some simulations have been done as follows. First, with the total current intensity and the relative yields of different charge states for carbon ions measured at the different distance from the target, the absolute current intensities and time-dependences for different charge states are scaled to the exit of the laser ion source in the DPIS. Then with these derived values as the input parameters, the extraction of carbon beam from the laser ion source to the radio frequency quadrupole with DPIS is simulated, which is well agreed with the experiment results.

  20. Optimization and control of two-component radially self-accelerating beams

    SciTech Connect (OSTI)

    Vetter, Christian; Eichelkraut, Toni; Ornigotti, Marco; Szameit, Alexander

    2015-11-23

    We report on the properties of radially self-accelerating intensity distributions consisting of two components in the angular frequency domain. We show how this subset of solutions, in literature also known as helicon beams, possesses peculiar characteristics that enable a better control over its properties. In this work, we present a step-by-step optimization procedure to achieve the best possible intensity contrast, a distinct rotation rate and long propagation lengths. All points are discussed on a theoretical basis and are experimentally verified.

  1. Commissioning of the Varian TrueBeam linear accelerator: A multi-institutional study

    SciTech Connect (OSTI)

    Glide-Hurst, C.; Bellon, M.; Wen, N.; Zhao, B.; Chetty, I. J.; Foster, R.; Speiser, M.; Solberg, T.; Altunbas, C.; Westerly, D.; Miften, M.; Altman, M.

    2013-03-15

    Purpose: Latest generation linear accelerators (linacs), i.e., TrueBeam (Varian Medical Systems, Palo Alto, CA) and its stereotactic counterpart, TrueBeam STx, have several unique features, including high-dose-rate flattening-filter-free (FFF) photon modes, reengineered electron modes with new scattering foil geometries, updated imaging hardware/software, and a novel control system. An evaluation of five TrueBeam linacs at three different institutions has been performed and this work reports on the commissioning experience. Methods: Acceptance and commissioning data were analyzed for five TrueBeam linacs equipped with 120 leaf (5 mm width) MLCs at three different institutions. Dosimetric data and mechanical parameters were compared. These included measurements of photon beam profiles (6X, 6XFFF, 10X, 10XFFF, 15X), photon and electron percent depth dose (PDD) curves (6, 9, 12 MeV), relative photon output factors (Scp), electron cone factors, mechanical isocenter accuracy, MLC transmission, and dosimetric leaf gap (DLG). End-to-end testing and IMRT commissioning were also conducted. Results: Gantry/collimator isocentricity measurements were similar (0.27-0.28 mm), with overall couch/gantry/collimator values of 0.46-0.68 mm across the three institutions. Dosimetric data showed good agreement between machines. The average MLC DLGs for 6, 10, and 15 MV photons were 1.33 {+-} 0.23, 1.57 {+-} 0.24, and 1.61 {+-} 0.26 mm, respectively. 6XFFF and 10XFFF modes had average DLGs of 1.16 {+-} 0.22 and 1.44 {+-} 0.30 mm, respectively. MLC transmission showed minimal variation across the three institutions, with the standard deviation <0.2% for all linacs. Photon and electron PDDs were comparable for all energies. 6, 10, and 15 MV photon beam quality, %dd(10){sub x} varied less than 0.3% for all linacs. Output factors (Scp) and electron cone factors agreed within 0.27%, on average; largest variations were observed for small field sizes (1.2% coefficient of variation, 10 MV, 2

  2. Experimental and Simulated Characterization of a Beam Shaping Assembly for Accelerator- Based Boron Neutron Capture Therapy (AB-BNCT)

    SciTech Connect (OSTI)

    Burlon, Alejandro A.; Valda, Alejandro A.; Girola, Santiago; Minsky, Daniel M.; Kreiner, Andres J.

    2010-08-04

    In the frame of the construction of a Tandem Electrostatic Quadrupole Accelerator facility devoted to the Accelerator-Based Boron Neutron Capture Therapy, a Beam Shaping Assembly has been characterized by means of Monte-Carlo simulations and measurements. The neutrons were generated via the {sup 7}Li(p, n){sup 7}Be reaction by irradiating a thick LiF target with a 2.3 MeV proton beam delivered by the TANDAR accelerator at CNEA. The emerging neutron flux was measured by means of activation foils while the beam quality and directionality was evaluated by means of Monte Carlo simulations. The parameters show compliance with those suggested by IAEA. Finally, an improvement adding a beam collimator has been evaluated.

  3. Recent progress in the development of a circular ion induction accelerator for space charge dominated beams at LLNL

    SciTech Connect (OSTI)

    Ahle, L; Autrey, D; Barnard, J; Berners, D; Craig, G; Debeling, A; Eylon, S; Friedman, A; Fritz, W; Grote, D P; Halaxa, E; Hanks, R L; Hernandez, M; Judd, D L; Kirbie, H C; Logan, B G; Lund, S M; Mant, G; Molvik, A W; Reginato, L; Sangster, T C; Sharp, W M

    1998-08-19

    The Heavy Ion Fusion Group at Lawrence Livermore National Laboratory has for several years been developing the world's first circular ion induction accelerator. This machine has recently been extended to 90 degrees, or 10 half-lattice periods (HLP) with full beam transport. In addition, induction cores have been installed on five of the HLP's, each with an independent arbitrary waveform pulser. An arbitrary waveform pulser for the bending electrostatic dipoles has also been enabled. Together, they have allowed the first attempts at coordinated bending and acceleration of the beam. The results of these first attempts will be reported on in the paper by examining the output of various diagnostic devices, such as the capacitive Beam Probes (C-probes), slit scanners, and the Gated Beam Imager(GBI).

  4. Mode trap for absorbing transverse modes of an accelerated electron beam

    DOE Patents [OSTI]

    Chojnacki, Eric P.

    1994-01-01

    A mode trap to trap and absorb transverse modes formed by a beam in a linear accelerator includes a waveguide having a multiplicity of electrically conductive (preferably copper) irises and rings, each iris and ring including an aperture, and the irises and rings being stacked in a side-by-side, alternating fashion such that the apertures of the irises and rings are concentrically aligned. An absorbing material layer such as a dielectric is embedded in each iris and ring, and this absorbing material layer encircles, but is circumferentially spaced from its respective aperture. Each iris and ring includes a plurality of circumferentially spaced slots around its aperture and extending radially out toward its absorbing material layer.

  5. Mode trap for absorbing transverse modes of an accelerated electron beam

    DOE Patents [OSTI]

    Chojnacki, E.P.

    1994-05-31

    A mode trap to trap and absorb transverse modes formed by a beam in a linear accelerator includes a waveguide having a multiplicity of electrically conductive (preferably copper) irises and rings, each iris and ring including an aperture, and the irises and rings being stacked in a side-by-side, alternating fashion such that the apertures of the irises and rings are concentrically aligned. An absorbing material layer such as a dielectric is embedded in each iris and ring, and this absorbing material layer encircles, but is circumferentially spaced from its respective aperture. Each iris and ring includes a plurality of circumferentially spaced slots around its aperture and extending radially out toward its absorbing material layer. 9 figs.

  6. Final Report 200 MW L-Band Annular Beam Klystron for Accelerators

    SciTech Connect (OSTI)

    Read, Michael; Ferguson, Patrick; Ives, Lawrence; Song, Liqun; Carlsten, Bruce; Fazio, Michael

    2009-02-11

    This program developed a 200 MW, 1.3 GHz, Annular Beam Klystron (ABK) for accelerator systems. An ABK provides lower impedance than a conventional klystron, making it possible to produce higher RF powers with lower voltages. With a higher power per unit, fewer klystrons would be required for a large accelerator. Lower voltage also simplifies and reduces the cost of the power supply system. Both features will significantly lower the cost of an RF system. This device operates at 475 kV. The klystron uses a magnetron injection gun producing 1100 A in one microsecond pulses. Power is extracted into fundamental rectangular waveguide through two output windows. The predicted gain is approximately 45 dB with estimated efficiency of 45%. The klystron was assembled, but no facility was available for testing. Consequently, no high power performance measurements are available. Because the assembled klystron is approximately 15 feet long, it was disassembled for storage. It can be reassembled should a use materialize.

  7. Final Report: Advanced Concepts for Ultrahigh Brightness and Low Temperature Beams Progress Report

    SciTech Connect (OSTI)

    Wurtele, Jonathan S.; Fajans, Joel

    2015-06-01

    This grant supported research on techniques to manipulate and combine positrons and antiprotons to synthesize, and to probe, antihydrogen. The majority of the research was conducted as part of the ALPHA Collaboration at CERN. Using ideas and techniques from accelerator physics, we proposed a new method for measuring the the gravitational attraction of antihydrogen to the Earth's field. ALPHA reported the first precision charge measurement on antihydrogen and a crude bound on its gravitational dynamics in the Earth's field. We proposed using a stochastic acceleration method to measure any putative charge of antihydrogen and built numerical models of the mixing of antiprotons and positrons. Further research included proposing the radiator-first concept for operating an X-ray free electron laser driven by a high repetition rate bunch source and studying scattering in passive foil-based ion focusing systems.

  8. GPU-accelerated regularized iterative reconstruction for few-view cone beam CT

    SciTech Connect (OSTI)

    Matenine, Dmitri; Goussard, Yves

    2015-04-15

    Purpose: The present work proposes an iterative reconstruction technique designed for x-ray transmission computed tomography (CT). The main objective is to provide a model-based solution to the cone-beam CT reconstruction problem, yielding accurate low-dose images via few-views acquisitions in clinically acceptable time frames. Methods: The proposed technique combines a modified ordered subsets convex (OSC) algorithm and the total variation minimization (TV) regularization technique and is called OSC-TV. The number of subsets of each OSC iteration follows a reduction pattern in order to ensure the best performance of the regularization method. Considering the high computational cost of the algorithm, it is implemented on a graphics processing unit, using parallelization to accelerate computations. Results: The reconstructions were performed on computer-simulated as well as human pelvic cone-beam CT projection data and image quality was assessed. In terms of convergence and image quality, OSC-TV performs well in reconstruction of low-dose cone-beam CT data obtained via a few-view acquisition protocol. It compares favorably to the few-view TV-regularized projections onto convex sets (POCS-TV) algorithm. It also appears to be a viable alternative to full-dataset filtered backprojection. Execution times are of 1–2 min and are compatible with the typical clinical workflow for nonreal-time applications. Conclusions: Considering the image quality and execution times, this method may be useful for reconstruction of low-dose clinical acquisitions. It may be of particular benefit to patients who undergo multiple acquisitions by reducing the overall imaging radiation dose and associated risks.

  9. Target design optimization for an electron accelerator driven subcritical facility with circular and square beam profiles.

    SciTech Connect (OSTI)

    Gohar, M. Y. A; Sofu, T.; Zhong, Z.; Belch, H.; Naberezhnev, D.; Nuclear Engineering Division

    2008-10-30

    A subcritical facility driven by an electron accelerator is planned at the Kharkov Institute of Physics and Technology (KIPT) in Ukraine for medical isotope production, materials research, training, and education. The conceptual design of the facility is being pursued through collaborations between ANL and KIPT. As part of the design effort, the high-fidelity analyses of various target options are performed with formulations to reflect the realistic configuration and the three dimensional geometry of each design. This report summarizes the results of target design optimization studies for electron beams with two different beam profiles. The target design optimization is performed via the sequential neutronic, thermal-hydraulic, and structural analyses for a comprehensive assessment of each configuration. First, a target CAD model is developed with proper emphasis on manufacturability to provide a basis for separate but consistent models for subsequent neutronic, thermal-hydraulic, and structural analyses. The optimizations are pursued for maximizing the neutron yield, streamlining the flow field to avoid hotspots, and minimizing the thermal stresses to increase the durability. In addition to general geometric modifications, the inlet/outlet channel configurations, target plate partitioning schemes, flow manipulations and rates, electron beam diameter/width options, and cladding material choices are included in the design optimizations. The electron beam interactions with the target assembly and the neutronic response of the subcritical facility are evaluated using the MCNPX code. the results for the electron beam energy deposition, neutron generation, and utilization in the subcritical pile are then used to characterize the axisymmetric heat generation profiles in the target assembly with explicit simulations of the beam tube, the coolant, the clad, and the target materials. Both tungsten and uranium are considered as target materials. Neutron spectra from tungsten

  10. 9 GeV energy gain in a beam-driven plasma wakefield accelerator

    Office of Scientific and Technical Information (OSTI)

    ... The mechanism can be described as a compact beam energy transformer, increasing the voltage of the trailing beam at the expense of that of the drive beam. Energy is first ...

  11. Low-field permanent magnet quadrupoles in a new relativistic-klystron two-beam accelerator design

    SciTech Connect (OSTI)

    Yu, S.; Sessler, A.

    1995-02-01

    Permanent magnets play a central role in the new relativistic klystron two-beam-accelerator design. The two key goals of this new design, low cost and the suppression of beam break-up instability are both intimately tied to the permanent magnet quadrupole focusing system. A recently completed systems study by a joint LBL-LLNL team concludes that a power source for a 1 TeV center-of-mass Next Linear Collider based on the new TBA design can be as low as $1 billion, and the efficiency (wall plug to rf) is estimated to be 36%. End-to-end simulations of longitudinal and transverse beam dynamics show that the drive beam is stable over the entire TBA unit.

  12. Passive tailoring of laser-accelerated ion beam cut-off energy by using double foil assembly

    SciTech Connect (OSTI)

    Chen, S. N. Brambrink, E.; Mancic, A.; Romagnani, L.; Audebert, P.; Fuchs, J.; Robinson, A. P. L.; Antici, P.; Dipartimento SBAI, Università di Roma « La Sapienza », Via Scarpa 14-16, 00165 Roma; INRS-Énergie et Matériaux, 1650 bd. L. Boulet, Varennes, J3X1S2 Québec ; D'Humières, E.; Centre de Physique Théorique, CNRS-Ecole Polytechnique, 91128 Palaiseau; University of Bordeaux—CNRS—CEA, CELIA, UMR5107, 33405 Talence ; Gaillard, S.; Grismayer, T.; Mora, P.; Pépin, H.

    2014-02-15

    A double foil assembly is shown to be effective in tailoring the maximum energy produced by a laser-accelerated proton beam. The measurements compare favorably with adiabatic expansion simulations, and particle-in-cell simulations. The arrangement proposed here offers for some applications a simple and passive way to utilize simultaneously highest irradiance lasers that have best laser-to-ion conversion efficiency while avoiding the production of undesired high-energy ions.

  13. Acceleration of 500 keV Negative Ion Beams By Tuning Vacuum Insulation Distance On JT-60 Negative Ion Source

    SciTech Connect (OSTI)

    Kojima, A.; Hanada, M.; Tanaka, Y.; Taniguchi, M.; Kashiwagi, M.; Inoue, T.; Umeda, N.; Watanabe, K.; Tobari, H.; Kobayashi, S.; Yamano, Y.; Grisham, L. R.

    2011-09-26

    Acceleration of a 500 keV beam up to 2.8 A has been achieved on a JT-60U negative ion source with a three-stage accelerator by overcoming low voltage holding which is one of the critical issues for realization of the JT-60SA ion source. In order to improve the voltage holding, preliminary voltage holding tests with small-size grids with uniform and locally intense electric fields were carried out, and suggested that the voltage holding was degraded by both the size and local electric field effects. Therefore, the local electric field was reduced by tuning gap lengths between the large size grids and grid support structures of the accelerator. Moreover, a beam radiation shield which limited extension of the minimum gap length was also optimized so as to reduce the local electric field while maintaining the shielding effect. These modifications were based on the experiment results, and significantly increased the voltage holding from <150 kV/stage for the original configuration to 200 kV/stage. These techniques for improvement of voltage holding should also be applicable to other large ion sources accelerators such as those for ITER.

  14. Extended Plate and Beam Wall System: Concept Investigation and Initial Evaluation

    SciTech Connect (OSTI)

    Wiehagen, J.; Kochkin, V.

    2015-08-01

    A new and innovative High-R wall design, referred to as the Extended Plate & Beam (EP&B), is under development. The EP&B system uniquely integrates foam sheathing insulation with wall framing such that wood structural panels are installed exterior of the foam sheathing, enabling the use of standard practices for installation of drainage plane, windows and doors, claddings, cavity insulation, and the standard exterior foam sheathing installation approach prone to damage of the foam during transportation of prefabricated wall panels. As part of the ongoing work, the EP&B wall system concept has undergone structural verification testing and has been positively vetted by a group of industry stakeholders. Having passed these initial milestone markers, the advanced wall system design has been analyzed to assess cost implications relative to other advanced wall systems, undergone design assessment to develop construction details, and has been evaluated to develop representative prescriptive requirements for the building code. This report summarizes the assessment steps conducted to-date and provides details of the concept development.

  15. Operating instructions for ORELA (Oak Ridge Electron Linear Accelerator) positron beam line

    SciTech Connect (OSTI)

    Donohue, D.L.; Hulett, L.D. Jr.; Lewis, T.A.

    1990-11-01

    This report will contain details of the construction and operation of the positron beam line. Special procedures which are performed on a less frequent basis will also be described. Appendices will contain operating instructions for experiments which make use of the positron beam and are connected to the beam line. Finally, a review of safety-related considerations will be presented.

  16. Concept, implementation and commissioning of the automation system for the accelerator module test facility AMTF

    SciTech Connect (OSTI)

    Bckmann, Torsten A.; Korth, Olaf; Clausen, Matthias; Schoeneburg, Bernd

    2014-01-29

    The European XFEL project launched on June 5, 2007 will require about 103 accelerator modules as a main part of the XFEL linear accelerator. All superconducting components constituting the accelerator module like cavities and magnets have to be tested before the assembly. For the tests of the individual cavities and the complete modules an XFEL Accelerator Module Test Facility (AMTF) has been erected at DESY. The process control system EPICS (Experimental Physics and Industrial Control System) is used to control and operate the cryogenic plant and all its subcomponents. A complementary component of EPICS is the Open Source software suit CSS (Control System Studio). CSS is an integrated engineering, maintenance and operating tool for EPICS. CSS enables local and remote operating and monitoring of the complete system and thus represents the human machine interface. More than 250 PROFIBUS nodes work at the accelerator module test facility. DESY installed an extensive diagnostic and condition monitoring system. With these diagnostic tools it is possible to examine the correct installation and configuration of all PROFIBUS nodes in real time. The condition monitoring system based on FDT/DTM technology shows the state of the PROFIBUS devices at a glance. This information can be used for preventive maintenance which is mandatory for continuous operation of the AMTF facility. The poster will describe all steps form engineering to implementation and commissioning.

  17. The APEX Pulse Shaping Project for PBFA II (Particle Beam Fusion Accelerator II)

    SciTech Connect (OSTI)

    Crow, J.T.; Allshouse, G.O.; Neau, E.L.; Olson, C.L.; Slutz, S.A.

    1987-01-01

    The APEX Project will develop an ion beam pulse-shaping and target standoff capability for installation on PBFA II. The project includes development of an efficient focusing extraction ion diode and plasma transport channels for ion beam propagation over several meters. The ion beam will have a pulse shape, power and area appropriate for investigating D-T fusion targets designed for pulse-shaped ion beams. Target simulations will determine the pulse shape needed on target. The system, as presently conceived, will use a single diode and transport channel, and a target designed for illumination by a single ion beam.

  18. D-Cluster Converter Foil for Laser-Accelerated Deuteron Beams: Towards Deuteron-Beam-Driven Fast Ignition

    SciTech Connect (OSTI)

    Miley, George H.

    2012-10-24

    Fast Ignition (FI) uses Petawatt laser generated particle beam pulse to ignite a small volume called a pre-compressed Inertial Confinement Fusion (ICF) target, and is the favored method to achieve the high energy gain per target burn needed for an attractive ICF power plant. Ion beams such as protons, deuterons or heavier carbon ions are especially appealing for FI as they have relative straight trajectory, and easier to focus on the fuel capsule. But current experiments have encountered problems with the 'converter-foil' which is irradiated by the Petawatt laser to produce the ion beams. The problems include depletion of the available ions in the convertor foils, and poor energy efficiency (ion beam energy/ input laser energy). We proposed to develop a volumetrically-loaded ultra-high-density deuteron deuterium cluster material as the basis for converter-foil for deuteron beam generation. The deuterons will fuse with the ICF DT while they slow down, providing an extra 'bonus' energy gain in addition to heating the hot spot. Also, due to the volumetric loading, the foil will provide sufficient energetic deuteron beam flux for 'hot spot' ignition, while avoiding the depletion problem encountered by current proton-driven FI foils. After extensive comparative studies, in Phase I, high purity PdO/Pd/PdO foils were selected for the high packing fraction D-Cluster converter foils. An optimized loading process has been developed to increase the cluster packing fraction in this type of foil. As a result, the packing fraction has been increased from 0.1% to 10% - meeting the original Phase I goal and representing a significant progress towards the beam intensities needed for both FI and pulsed neutron applications. Fast Ignition provides a promising approach to achieve high energy gain target performance needed for commercial Inertial Confinement Fusion (ICF). This is now a realistic goal for near term in view of the anticipated ICF target burn at the National Ignition

  19. Tailoring the laser pulse shape to improve the quality of the self-injected electron beam in laser wakefield acceleration

    SciTech Connect (OSTI)

    Upadhyay, Ajay K.; Samant, Sushil A.; Krishnagopal, S.

    2013-01-15

    In laser wakefield acceleration, tailoring the shape of the laser pulse is one way of influencing the laser-plasma interaction and, therefore, of improving the quality of the self-injected electron beam in the bubble regime. Using three-dimensional particle-in-cell simulations, the evolution dynamics of the laser pulse and the quality of the self-injected beam, for a Gaussian pulse, a positive skew pulse (i.e., one with sharp rise and slow fall), and a negative skew pulse (i.e., one with a slow rise and sharp fall) are studied. It is observed that with a negative skew laser pulse there is a substantial improvement in the emittance (by around a factor of two), and a modest improvement in the energy-spread, compared to Gaussian as well as positive skew pulses. However, the injected charge is less in the negative skew pulse compared to the other two. It is also found that there is an optimal propagation distance that gives the best beam quality; beyond this distance, though the energy increases, the beam quality deteriorates, but this deterioration is least for the negative skew pulse. Thus, the negative skew pulse gives an improvement in terms of beam quality (emittance and energy spread) over what one can get with a Gaussian or positive skew pulse. In part, this is because of the lesser injected charge, and the strong suppression of continuous injection for the negative skew pulse.

  20. Detector dose response in megavoltage small photon beams. I. Theoretical concepts

    SciTech Connect (OSTI)

    Bouchard, Hugo Duane, Simon; Seuntjens, Jan; Kamio, Yuji; Palmans, Hugo

    2015-10-15

    Purpose: To explain the reasons for significant quality correction factors in megavoltage small photon fields and clarify the underlying concepts relevant to dosimetry under such conditions. Methods: The validity of cavity theory and the requirement of charged particle equilibrium (CPE) are addressed from a theoretical point of view in the context of nonstandard beams. Perturbation effects are described into four main subeffects, explaining their nature and pointing out their relative importance in small photon fields. Results: It is demonstrated that the failure to meet classical cavity theory requirements, such as CPE, is not the reason for significant quality correction factors. On the contrary, it is shown that the lack of CPE alone cannot explain these corrections and that what matters most, apart from volume averaging effects, is the relationship between the lack of CPE in the small field itself and the density of the detector cavity. The density perturbation effect is explained based on Fano’s theorem, describing the compensating effect of two main contributions to cavity absorbed dose. Using the same approach, perturbation effects arising from the difference in atomic properties of the cavity medium and the presence of extracameral components are explained. Volume averaging effects are also discussed in detail. Conclusions: Quality correction factors of small megavoltage photon fields are mainly due to differences in electron density between water and the detector medium and to volume averaging over the detector cavity. Other effects, such as the presence of extracameral components and differences in atomic properties of the detection medium with respect to water, can also play an accentuated role in small photon fields compared to standard beams.

  1. Beam dynamics study of a 30 MeV electron linear accelerator to drive a neutron source

    SciTech Connect (OSTI)

    Kumar, Sandeep; Yang, Haeryong; Kang, Heung-Sik

    2014-02-14

    An experimental neutron facility based on 32 MeV/18.47 kW electron linac has been studied by means of PARMELA simulation code. Beam dynamics study for a traveling wave constant gradient electron accelerator is carried out to reach the preferential operation parameters (E = 30 MeV, P = 18 kW, dE/E < 12.47% for 99% particles). The whole linac comprises mainly E-gun, pre-buncher, buncher, and 2 accelerating columns. A disk-loaded, on-axis-coupled, 2π/3-mode type accelerating rf cavity is considered for this linac. After numerous optimizations of linac parameters, 32 MeV beam energy is obtained at the end of the linac. As high electron energy is required to produce acceptable neutron flux. The final neutron flux is estimated to be 5 × 10{sup 11} n/cm{sup 2}/s/mA. Future development will be the real design of a 30 MeV electron linac based on S band traveling wave.

  2. Guiding and collimation of laser-accelerated proton beams using thin foils followed with a hollow plasma channel

    SciTech Connect (OSTI)

    Xiao, K. D.; Zhou, C. T.; Qiao, B.; He, X. T.

    2015-09-15

    It is proposed that guided and collimated proton acceleration by intense lasers can be achieved using an advanced target—a thin foil followed by a hollow plasma channel. For the advanced target, the laser-accelerated hot electrons can be confined in the hollow channel at the foil rear side, which leads to the formation of transversely localized, Gaussian-distributed sheath electric field and resultantly guiding of proton acceleration. Further, due to the hot electron flow along the channel wall, a strong focusing transverse electric field is induced, taking the place of the original defocusing one driven by hot electron pressure in the case of a purely thin foil target, which results in collimation of proton beams. Two-dimensional particle-in-cell simulations show that collimated proton beams with energy about 20 MeV and nearly half-reduced divergence of 26° are produced at laser intensities 10{sup 20 }W/cm{sup 2} by using the advanced target.

  3. Means for the focusing and acceleration of parallel beams of charged particles. [Patent application

    DOE Patents [OSTI]

    Maschke, A.W.

    1980-09-23

    Apparatus for focusing beams of charged particles comprising planar arrays of electrostatic quadrupoles. The array may be assembled from a single component which comprises a support plate containing uniform rows of poles. Each pole is separated by a hole through the plate designed to pass a beam. Two such plates may be positioned with their poles intermeshed to form a plurality of quadrupoles.

  4. Means for the focusing and acceleration of parallel beams of charged particles

    DOE Patents [OSTI]

    Maschke, Alfred W.

    1982-09-21

    Apparatus for focusing beams of charged particles comprising planar arrays of electrostatic quadrupoles. The array may be assembled from a single component which comprises a support plate containing uniform rows of poles. Each pole is separated by a hole through the plate designed to pass a beam. Two such plates may be positioned with their poles intermeshed to form a plurality of quadrupoles.

  5. Particle Rate and Host Accelerator Beam Loss on the MICE Experiment

    SciTech Connect (OSTI)

    Dobbs, Adam James

    2011-10-01

    A study is presented of particle rates in the MICE Muon Beamline and their relationship to beam loss produced in ISIS. A brief overview of neutrino physics is presented, together with a discussion on the Neutrino Factory as a motivation for MICE. An overview of MICE itself is then presented, highlighting the need for a systematic understanding of the relationship between the MICE target parameters, ISIS beam loss, and MICE particle rate. The variation of beam loss with target depth is examined and observed to be non-linear. The variation of beam loss with respect to the target dip time in the ISIS cycle is examined and observed to be approximately linear for dip times between 11.1 ms and 12.6 ms after ISIS injection, before tailing at earlier dip times. The variation of beam loss with particle rate is also observed to follow an approximately linear relationship from 0.05 V.ms to 4.7 V.ms beam loss, with a further strong indication that this continues up to 7.1 V.ms. Particle identification using time-of-flight data is used to give an insight into the relative abundances of each particle species present in the MICE beam. Estimates of muon rate are then produced as a function of beam loss. At a level of 2 V.ms beam loss ~10:9 muons per spill for a 3.2 ms spill with negative π → μ optics, and ~31:1 muons per 1 ms spill with positive π → μ optics are observed. Simulations using the ORBIT particle tracking code of the beam loss distributions around the ISIS ring, caused by the MICE target, are also presented and the implications for MICE running discussed.

  6. PBFA II (Particle Beam Fusion Accelerator 2) APEX pulse shaping project

    SciTech Connect (OSTI)

    Crow, J.T.

    1986-01-01

    The APEX Project will develop a system of ion beam pulse-shaping and target standoff for installation on PBFA II. The project will include development of an efficient ion diode and plasma transport channels for ion beam propagation over several meters. The ion beam will have a pulse shape, power and area appropriate for achieving gain from a D-T fusion target. The system, as presently conceived, will use a single diode, single transport channel, and a target designed for single-sided illumination. The basic APEX system is described.

  7. Neutral-beam development plan, FY 1982-1987

    SciTech Connect (OSTI)

    Not Available

    1981-09-01

    The following chapters are included: (1) status of BNL negative ion source development, (2) source development program plan, (3) status of beam transport and acceleration, (4) accelerator development program plan, (5) neutralizer concepts, (6) neutralization program plan, (7) neutral beam systems, (8) test facilities, (9) program milestones and time schedules, (10) organization and Grumman participation, and (11) funding tables. (MOW)

  8. A facility for accelerator research and education at Fermilab

    SciTech Connect (OSTI)

    Church, Mike; Nagaitsev, Sergei; /Fermilab

    2009-01-01

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

  9. A study of the structural activation caused by proton beam loss in the {open_quotes}accelerator production of tritium{close_quotes} LINAC

    SciTech Connect (OSTI)

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

    1997-01-01

    The Accelerator Production of Tritium (APT) project at Los Alamos National Laboratory makes use of a high power linear proton accelerator to produce neutrons via spallation reactions m a heavy metal target. The fast spallation neutrons are moderated by a heavy water blanket, and used to produce tritium by means of the reaction: {sup 3}He(n,p)T, APT 1993. Various accelerator designs are currently under consideration. At the time when this study was performed, the project called for a 1 GeV proton linear accelerator with a beam current of 200 mA, i.e., a proton beam power of 200 MW. Given the high power at which the APT accelerator is expected to operate, as well as the heavy maintenance that is likely to be required to keep it operating, it is essential to consider health physics issues at an early stage of the design.

  10. Spectral properties of laser-accelerated mid-Z MeV/u ion beams

    SciTech Connect (OSTI)

    Hegelich, B.M.; Albright, B.; Cobble, J.; Gautier, C.; Johnson, R.; Letzring, S.; Fernandez, J.C. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Audebert, P.; Fuchs, J. [Laboratoire pour l'Utilisation des Lasers Intenses, Ecole Polytechnique, 91128 Palaiseau (France); Blazevic, A.; Brambrink, E.; Geissel, M.; Roth, M. [Technische Universitaet Darmstadt, 64289 Darmstadt (Germany); Cowan, T.; Kemp, A. [Physics Department, MS-220, University of Nevada, Reno, Nevada 89557 (United States); Gauthier, J.C. [Centre Lasers Intenses et Applications (CELIA), UMR 5107 CNRS, Universite Bordeaux 1, CEA, Universite Bordeaux 1, 33405 Talence (France); Habs, D.; Schramm, U.; Schreiber, J. [Ludwig-Maximilian Universitaet Muenchen, 85748 Garching (Germany); Karsch, S. [Max-Planck-Institut fuer Quantenoptik, 85748 Garching (Germany)] (and others)

    2005-05-15

    Collimated jets of beryllium, carbon, oxygen, fluorine, and palladium ions with >1 MeV/nucleon energies are observed from the rear surface of thin foils irradiated with laser intensities of up to 5x10{sup 19} W/cm{sup 2}. The normally dominant proton acceleration is suppressed when the target is subjected to Joule heating to remove hydrogen-bearing contaminant. This inhibits screening effects and permits effective energy transfer to and acceleration of heavier ion species. The influence of remnant protons on the spectral shape of the next highest charge-to-mass ratio species is shown. Particle-in-cell simulations confirming the experimental findings are presented.

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

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

    Fermilab's Accelerator Complex photo Fermilab's accelerator complex comprises seven particle accelerators and storage rings. It produces the world's most powerful, high-energy neutrino beam and provides proton beams for various experiments and R&D programs. Fermilab's accelerator complex delivers high-intensity neutrino beams and provides optimal beam for a broad range of new and existing experiments, including the Deep Underground Neutrino Experiment, Muon g-2 and Mu2e. Fermilab's

  12. Carrigan, Jr., Richard A. [Fermi National Accelerator Lab. (FNAL...

    Office of Scientific and Technical Information (OSTI)

    Accelerator Lab. (FNAL), Batavia, IL (United States) 43 PARTICLE ACCELERATORS; BEAM OPTICS; CHANNELING; ATTENUATION; BEAM EXTRACTION; BENDING; CRYSTALS; MESON BEAMS; BEAMS;...

  13. LINEAR ACCELERATOR

    DOE Patents [OSTI]

    Colgate, S.A.

    1958-05-27

    An improvement is presented in linear accelerators for charged particles with respect to the stable focusing of the particle beam. The improvement consists of providing a radial electric field transverse to the accelerating electric fields and angularly introducing the beam of particles in the field. The results of the foregoing is to achieve a beam which spirals about the axis of the acceleration path. The combination of the electric fields and angular motion of the particles cooperate to provide a stable and focused particle beam.

  14. Tevatron End-of-Run Beam Physics Experiments

    SciTech Connect (OSTI)

    Valishev, A.; Gu, X.; Miyamoto, R.; White, S.; Schmidt, F.; Qiang, J.; /LBNL

    2012-05-01

    Before the Tevatron Collider Run II ended in September of 2011, a number of specialized beam study periods were dedicated to the experiments on various accelerator physics concepts and effects during the last year of the machine operation. The study topics included collimation with bent crystals and hollow electron beams, diffusion measurements and various aspects of beam-beam interactions. In this report we concentrate on the subject of beam-beam interactions, summarizing the results of beam experiments. The covered topics include offset collisions, coherent beam stability, effect of the bunch-length-to-beta-function ratio, and operation of AC dipole with colliding beams.

  15. Non-Invasive Beam Detection in a High-Average Power Electron Accelerator

    SciTech Connect (OSTI)

    Williams, J.; Biedron, S.; Harris, J.; Martinez, J.; Milton, S. V.; Van Keuren, J.; Benson, Steve V.; Evtushenko, Pavel; Neil, George R.; Zhang, Shukui

    2013-12-01

    For a free-electron laser (FEL) to work effectively the electron beam quality must meet exceptional standards. In the case of an FEL operating at infrared wavelengths in an amplifier configuration the critical phase space tends to be in the longitudinal direction. Achieving high enough longitudinal phase space density directly from the electron injector system of such an FEL is difficult due to space charge effects, thus one needs to manipulate the longitudinal phase space once the beam energy reaches a sufficiently high value. However, this is fraught with problems. Longitudinal space charge and coherent synchrotron radiation can both disrupt the overall phase space, furthermore, the phase space disruption is exacerbated by the longitudinal phase space manipulation process required to achieve high peak current. To achieve and maintain good FEL performance one needs to investigate the longitudinal emittance and be able to measure it during operation preferably in a non-invasive manner. Using the electro-optical sampling (EOS) method, we plan to measure the bunch longitudinal profile of a high-energy (~120-MeV), high-power (~10kW or more FEL output power) beam.

  16. Diagnostic of laser-accelerated ion beams for the ELIMED project

    SciTech Connect (OSTI)

    Torrisi, L.; INFN-Laboratori Nazionali del Sud, V. S. Sofia 64, 95123 Catania ; Cutroneo, M.; Cavallaro, S.; Andò, L.; Calcagno, L.; Musumeci, P.

    2013-07-26

    The laser-generated plasma, in non equilibrium conditions, has peculiar properties depending strongly on the laser parameters, on the target composition and on the target geometry. Different fast diagnostic techniques can be employed for the plasma characterization in terms of particles and photons emission, plasma temperature and density, ion energy distribution, angular emission, yield and electric field acceleration. Particular attention is devoted to the proton emission from hydrogenated targets and to the proton diagnostics by using time of flight techniques and Thomson parabola spectrometry. The diagnostic techniques will be presented and discussed on the base of the development of the ELIMED project.

  17. SU-E-T-597: Parameterization of the Photon Beam Dosimetry for a Commercial Linear Accelerator

    SciTech Connect (OSTI)

    Lebron, S; Lu, B; Yan, G; Kahler, D; Li, J; Barraclough, B; Liu, C

    2015-06-15

    Purpose: In radiation therapy, accurate data acquisition of photon beam dosimetric quantities is important for (1) beam modeling data input into a treatment planning system (TPS), (2) comparing measured and TPS modelled data, (3) a linear accelerator’s (linac) beam characteristics quality assurance process, and (4) establishing a standard data set for data comparison, etcetera. Parameterization of the photon beam dosimetry creates a portable data set that is easy to implement for different applications such as those previously mentioned. The aim of this study is to develop methods to parameterize photon percentage depth doses(PDD), profiles, and total scatter output factors(Scp). Methods: Scp, PDDs and profiles for different field sizes (from 2×2 to 40×40cm{sup 2}), depths and energies were measured in a linac using a three-dimensional water tank. All data were smoothed and profile data were also centered, symmetrized and geometrically scaled. The Scp and PDD data were analyzed using exponential functions. For modelling of open and wedge field profiles, each side was divided into three regions described by exponential, sigmoid and Gaussian equations. The model’s equations were chosen based on the physical principles described by these dosimetric quantities. The equations’ parameters were determined using a least square optimization method with the minimal amount of measured data necessary. The model’s accuracy was then evaluated via the calculation of absolute differences and distance–to–agreement analysis in low gradient and high gradient regions, respectively. Results: All differences in the PDDs’ buildup and the profiles’ penumbra regions were less than 2 mm and 0.5 mm, respectively. Differences in the low gradient regions were 0.20 ± 0.20% and 0.50 ± 0.35% for PDDs and profiles, respectively. For Scp data, all differences were less than 0.5%. Conclusion: This novel analytical model with minimum measurement requirements proved to accurately

  18. PRECISE ANGLE MONITOR BASED ON THE CONCEPT OF PENCIL-BEAM INTERFEROMETRY

    SciTech Connect (OSTI)

    QIAN,S.; TAKACS,P.

    2000-07-30

    The precise angle monitoring is a very important metrology task for research, development and industrial applications. Autocollimator is one of the most powerful and widely applied instruments for small angle monitoring, which is based on the principle of geometric optics. In this paper the authors introduce a new precise angle monitoring system, Pencil-beam Angle Monitor (PAM), base on pencil beam interferometry. Its principle of operation is a combination of physical and geometrical optics. The angle calculation method is similar to the autocollimator. However, the autocollimator creates a cross image but the precise pencil-beam angle monitoring system produces an interference fringe on the focal plane. The advantages of the PAM are: high angular sensitivity, long-term stability character making angle monitoring over long time periods possible, high measurement accuracy in the order of sub-microradian, simultaneous measurement ability in two perpendicular directions or on two different objects, dynamic measurement possibility, insensitive to the vibration and air turbulence, automatic display, storage and analysis by use of the computer, small beam diameter making the alignment extremely easy and longer test distance. Some test examples are presented.

  19. Preliminary Results of Mono-energetic Electron Beams from a Laser-plasma Accelerator Driven by 200 TW Femto Second Pulses

    SciTech Connect (OSTI)

    Taki, R.; Kameshima, T.; An, W. M.; Hua, J. F.; Huang, W. H.; Tang, C. X.; Gu, Y. Q.; Guo, Y.; Hong, W.; Jiao, C. Y.; Lin, Y. Z.; Liu, H. J.; Peng, H. S.; Sun, L.; Tang, C. M.; Wang, X. D.; Wen, T. S.; Wen, X. L.; Wu, Y. C.; Zhang, B. H.

    2006-11-27

    Relativistic mono-energetic electron beams have been demonstrated by worldwide laser-plasma accelerator experiments in the range of a few tens TW. Laser-plasma accelerator experiment has been carried out with 200TW, 30fs Ti:Sapphire laser pulses focused on helium gas-jets with F/8.7 optics. Intense mono-energetic electron beams have been produced in the energy range of 30 to 150 MeV by controlling plasma length and density precisely. Images of Thomson scattering and fluorescence side scattering from plasma indicate highly relativistic effects such as a long self-channeling and filamentation as well as energetic electron deflection and intense backward Raman scattering. Preliminary results of the first laser-plasma accelerator experiment in the range of 200TW femto second pulses are presented.

  20. Mesurement of the Decelerating Wake in a Plasma Wakefield Accelerator...

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: USDOE Country of Publication: United States Language: English Subject: 43 PARTICLE ACCELERATORS; ACCELERATION; ACCELERATORS; ELECTRON BEAMS; ELECTRONS; METERS; ...

  1. Linear Accelerator

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

    Linear Accelerator (LINAC) The core of the LANSCE facility is one of the nation's most powerful proton linear accelerators or LINAC. The LINAC at LANSCE has served the nation since 1972, providing the beam current required by all the experimental areas that support NNSA-DP and other DOE missions. The LINAC's capability to reliably deliver beam current is the key to the LANSCE's ability to do research-and thus the key to meeting NNSA and DOE mission deliverables. The LANSCE Accelerator The LANSCE

  2. Field calculations, single-particle tracking, and beam dynamics with space charge in the electron lens for the Fermilab Integrable Optics Test Accelerator

    SciTech Connect (OSTI)

    Noll, Daniel; Stancari, Giulio

    2015-11-17

    An electron lens is planned for the Fermilab Integrable Optics Test Accelerator as a nonlinear element for integrable dynamics, as an electron cooler, and as an electron trap to study space-charge compensation in rings. We present the main design principles and constraints for nonlinear integrable optics. A magnetic configuration of the solenoids and of the toroidal section is laid out. Singleparticle tracking is used to optimize the electron path. Electron beam dynamics at high intensity is calculated with a particle-in-cell code to estimate current limits, profile distortions, and the effects on the circulating beam. In the conclusions, we summarize the main findings and list directions for further work.

  3. Noninvasive referencing of intraocular tumors for external beam radiation therapy using optical coherence tomography: A proof of concept

    SciTech Connect (OSTI)

    Rüegsegger, Michael B.; Steiner, Patrick; Kowal, Jens H.; Geiser, Dominik; Pica, Alessia; Aebersold, Daniel M.

    2014-08-15

    Purpose: External beam radiation therapy is currently considered the most common treatment modality for intraocular tumors. Localization of the tumor and efficient compensation of tumor misalignment with respect to the radiation beam are crucial. According to the state of the art procedure, localization of the target volume is indirectly performed by the invasive surgical implantation of radiopaque clips or is limited to positioning the head using stereoscopic radiographies. This work represents a proof-of-concept for direct and noninvasive tumor referencing based on anterior eye topography acquired using optical coherence tomography (OCT). Methods: A prototype of a head-mounted device has been developed for automatic monitoring of tumor position and orientation in the isocentric reference frame for LINAC based treatment of intraocular tumors. Noninvasive tumor referencing is performed with six degrees of freedom based on anterior eye topography acquired using OCT and registration of a statistical eye model. The proposed prototype was tested based on enucleated pig eyes and registration accuracy was measured by comparison of the resulting transformation with tilt and torsion angles manually induced using a custom-made test bench. Results: Validation based on 12 enucleated pig eyes revealed an overall average registration error of 0.26 ± 0.08° in 87 ± 0.7 ms for tilting and 0.52 ± 0.03° in 94 ± 1.4 ms for torsion. Furthermore, dependency of sampling density on mean registration error was quantitatively assessed. Conclusions: The tumor referencing method presented in combination with the statistical eye model introduced in the past has the potential to enable noninvasive treatment and may improve quality, efficacy, and flexibility of external beam radiotherapy of intraocular tumors.

  4. Final Report for grant DE-FG02-06ER54888, "Simulation of Beam-Electron Cloud Interactions in Circular Accelerators Using Plasma Models"

    SciTech Connect (OSTI)

    Decyk, Viktor K.

    2012-11-27

    The primary goal of this collaborative proposal was to modify the code QuickPIC and apply it to study the long-time stability of beam propagation in low density electron clouds present in circular accelerators. The UCLA contribution to this collaborative proposal was in supporting the development of the pipelining scheme for the QuickPIC code, which extended the parallel scaling of this code by two orders of magnitude.

  5. SciDAC Advances and Applications in Computational Beam Dynamics

    SciTech Connect (OSTI)

    Ryne, R.; Abell, D.; Adelmann, A.; Amundson, J.; Bohn, C.; Cary, J.; Colella, P.; Dechow, D.; Decyk, V.; Dragt, A.; Gerber, R.; Habib, S.; Higdon, D.; Katsouleas, T.; Ma, K.-L.; McCorquodale, P.; Mihalcea, D.; Mitchell, C.; Mori, W.; Mottershead, C.T.; Neri, F.; Pogorelov, I.; Qiang, J.; Samulyak, R.; Serafini, D.; Shalf, J.; Siegerist, C.; Spentzouris, P.; Stoltz, P.; Terzic, B.; Venturini, M.; Walstrom, P.

    2005-06-26

    SciDAC has had a major impact on computational beam dynamics and the design of particle accelerators. Particle accelerators--which account for half of the facilities in the DOE Office of Science Facilities for the Future of Science 20 Year Outlook--are crucial for US scientific, industrial, and economic competitiveness. Thanks to SciDAC, accelerator design calculations that were once thought impossible are now carried routinely, and new challenging and important calculations are within reach. SciDAC accelerator modeling codes are being used to get the most science out of existing facilities, to produce optimal designs for future facilities, and to explore advanced accelerator concepts that may hold the key to qualitatively new ways of accelerating charged particle beams. In this poster we present highlights from the SciDAC Accelerator Science and Technology (AST) project Beam Dynamics focus area in regard to algorithm development, software development, and applications.

  6. About Accelerators | Jefferson Lab

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

    About Accelerators Jefferson Lab is home to two superconducting radiofrequency accelerators: the Continuous Electron Beam Accelerator Facility and the Free-Electron Laser. The CEBAF accelerator is a unique accelerator used to conduct investigations in the field of nuclear physics. It provides high-current, medium-energy electron beams concurrently to three experimental halls for the study of quarks and gluons, protons and neutrons and the nucleus of the atom. The Jefferson Lab Free-Electron

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

    SciTech Connect (OSTI)

    Cary, John R

    2014-09-08

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

  8. Ultra-low emittance beam generation using two-color ionization injection in a CO2 laser-driven plasma accelerator

    SciTech Connect (OSTI)

    Schroeder, Carl; Benedetti, Carlo; Bulanov, Stepan; Chen, Min; Esarey, Eric; Geddes, Cameron; Vay, J.; Yu, Lule; Leemans, Wim

    2015-05-21

    Ultra-low emittance (tens of nm) beams can be generated in a plasma accelerator using ionization injection of electrons into a wakefield. An all-optical method of beam generation uses two laser pulses of different colors. A long-wavelength drive laser pulse (with a large ponderomotive force and small peak electric field) is used to excite a large wakefield without fully ionizing a gas, and a short-wavelength injection laser pulse (with a small ponderomotive force and large peak electric field), co-propagating and delayed with respect to the pump laser, to ionize a fraction of the remaining bound electrons at a trapped wake phase, generating an electron beam that is accelerated in the wake. The trapping condition, the ionized electron distribution, and the trapped bunch dynamics are discussed. Expressions for the beam transverse emittance, parallel and orthogonal to the ionization laser polarization, are presented. An example is shown using a 10-micron CO2 laser to drive the wake and a frequency-doubled Ti:Al2O3 laser for ionization injection.

  9. Beam generation and planar imaging at energies below 2.40 MeV with carbon and aluminum linear accelerator targets

    SciTech Connect (OSTI)

    Parsons, David; Robar, James L.

    2012-07-15

    Purpose: Recent work has demonstrated improvement of image quality with low-Z linear accelerator targets and energies as low as 3.5 MV. In this paper, the authors lower the incident electron beam energy between 1.90 and 2.35 MeV and assess the improvement of megavoltage planar image quality with the use of carbon and aluminum linear accelerator targets. Methods: The bending magnet shunt current was adjusted in a Varian linear accelerator to allow selection of mean electron energy between 1.90 and 2.35 MeV. Linac set points were altered to increase beam current to allow experimental imaging in a practical time frame. Electron energy was determined through comparison of measured and Monte Carlo modeled depth dose curves. Planar image CNR and spatial resolution measurements were performed to quantify the improvement of image quality. Magnitudes of improvement are explained with reference to Monte Carlo generated energy spectra. Results: After modifications to the linac, beam current was increased by a factor greater than four and incident electron energy was determined to have an adjustable range from 1.90 MeV to 2.35 MeV. CNR of cortical bone was increased by a factor ranging from 6.2 to 7.4 and 3.7 to 4.3 for thin and thick phantoms, respectively, compared to a 6 MV therapeutic beam for both aluminum and carbon targets. Spatial resolution was degraded slightly, with a relative change of 3% and 10% at 0.20 lp/mm and 0.40 lp/mm, respectively, when reducing energy from 2.35 to 1.90 MV. The percentage of diagnostic x-rays for the beams examined here, ranges from 46% to 54%.Conclusion: It is possible to produce a large fraction of diagnostic energy x-rays by lowering the beam energy below 2.35 MV. By lowering the beam energy to 1.90 MV or 2.35 MV, CNR improves by factors ranging from 3.7 to 7.4 compared to a 6 MV therapy beam, with only a slight degradation of spatial resolution when lowering the energy from 2.35 MV to 1.90 MV.

  10. Investigation of Generation, Acceleration, Transport and Final Focusing of High-Intensity Heavy Ion Beams from Sources to Targets

    SciTech Connect (OSTI)

    Chiping Chen

    2006-10-26

    Under the auspices of the research grant, the Intense Beam Theoretical Research Goup at Massachusetts Institute of Technology's Plasma Science and Fusion Center made significant contributions in a number of important areas in the HIF and HEDP research, including: (a) Derivation of rms envelope equations and study of rms envelope dynamics for high-intensity heavy ion beams in a small-aperture AG focusing transport systems; (b) Identification of a new mechanism for chaotic particle motion, halo formation, and beam loss in high-intensity heavy ion beams in a small-aperture AG focusing systems; Development of elliptic beam theory; (d) Study of Physics Issues in the Neutralization Transport Experiment (NTX).

  11. Accelerators (5/5)

    SciTech Connect (OSTI)

    2009-07-09

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

  12. Accelerators (4/5)

    SciTech Connect (OSTI)

    2009-07-08

    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.

  13. Accelerators (3/5)

    SciTech Connect (OSTI)

    2009-07-07

    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.

  14. Accelerators (5/5)

    ScienceCinema (OSTI)

    None

    2011-10-06

    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.

  15. Accelerators (3/5)

    ScienceCinema (OSTI)

    None

    2011-10-06

    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.

  16. Accelerators (4/5)

    ScienceCinema (OSTI)

    None

    2011-10-06

    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.

  17. ADPF spoke cavity cryomodule concept

    SciTech Connect (OSTI)

    Kelley, J. P.; Roybal, P. L.; La Fave, R. P.; Waynert, J. A.; Schrage, D. L.; Schmierer, E. N.; Krawczyk, F. L.; Garnett, R. W.

    2001-01-01

    The Accelerator Driven Test Facility (ADTF) is being developed as a reactor concepts test bed for transmutation of nuclear waste. A 13.3 mA continuous-wave (CW) proton beam will be accelerated to 600 MeV and impinged on a spallation target. The subsequent neutron shower is used to create a nuclear reaction within a subcritical assembly of waste material that reduces the waste half-life from the order of 10{sup 5} years to 10{sup 2} years. Additionally, significant energy is produced that can be used to generate electrical power. The ADTF proton accelerator consists of room-temperature (RT) structures that accelerate the beam to 6.7-MeV and superconducting (SC) elements that boost the beam's energy to 600-MeV. Traditional SC elliptical cavities experience structural difficulties at low energies due to their geometry. Therefore, stiff-structured SC spoke cavities have been adopted for the energy range between 6.7 and 109 MeV. Elliptical cavities are used at the higher energies. This paper describes a multi-spoke-cavity cryomodule concept for ADTF.

  18. Production and dosimetry of simultaneous therapeutic photons and electrons beam by linear accelerator: A Monte Carlo study

    SciTech Connect (OSTI)

    Khledi, Navid; Sardari, Dariush; Arbabi, Azim; Ameri, Ahmad; Mohammadi, Mohammad

    2015-02-24

    Depending on the location and depth of tumor, the electron or photon beams might be used for treatment. Electron beam have some advantages over photon beam for treatment of shallow tumors to spare the normal tissues beyond of the tumor. In the other hand, the photon beam are used for deep targets treatment. Both of these beams have some limitations, for example the dependency of penumbra with depth, and the lack of lateral equilibrium for small electron beam fields. In first, we simulated the conventional head configuration of Varian 2300 for 16 MeV electron, and the results approved by benchmarking the Percent Depth Dose (PDD) and profile of the simulation and measurement. In the next step, a perforated Lead (Pb) sheet with 1mm thickness placed at the top of the applicator holder tray. This layer producing bremsstrahlung x-ray and a part of the electrons passing through the holes, in result, we have a simultaneous mixed electron and photon beam. For making the irradiation field uniform, a layer of steel placed after the Pb layer. The simulation was performed for 10×10, and 4×4 cm2 field size. This study was showed the advantages of mixing the electron and photon beam by reduction of pure electron's penumbra dependency with the depth, especially for small fields, also decreasing of dramatic changes of PDD curve with irradiation field size.

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

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

    Leading Accelerator Technology photo From blueprint to construction, Fermilab scientists and engineers develop particle accelerators to produce beams to take particle physics to the next level, collaborating with scientists and laboratories around the world to help build these complex machines. Researchers build accelerators to be efficient and robust along every step of the particle beam's path, from the time it's born to its termination on target. The machines themselves must be efficient,

  20. Safety training and safe operating procedures written for PBFA (Particle Beam Fusion Accelerator) II and applicable to other pulsed power facilities

    SciTech Connect (OSTI)

    Donovan, G.L.; Goldstein, S.A.

    1986-12-01

    To ensure that work in advancing pulsed power technology is performed with an acceptably low risk, pulsed power research facilities at Sandia National Laboratories must satisfy general safety guidelines established by the Department of Energy, policies and formats of the Environment, Safety, and Health (ES and H) Department, and detailed procedures formulated by the Pulsed Power Sciences Directorate. The approach to safety training and to writing safe operating procedures, and the procedures presented here are specific to the Particle Beam Fusion Accelerator II (PBFA II) Facility but are applicable as guidelines to other research and development facilities which have similar hazards.

  1. CEBAF beam loss accounting

    SciTech Connect (OSTI)

    Ursic, R.; Mahoney, K.; Hovater, C.; Hutton, A.; Sinclair, C.

    1995-12-31

    This paper describes the design and implementation of a beam loss accounting system for the CEBAF electron accelerator. This system samples the beam curent throughout the beam path and measures the beam current accurately. Personnel Safety and Machine Protection systems use this system to turn off the beam when hazardous beam losses occur.

  2. The CEBAF Electron Accelerator Project (Conference) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: 43 PARTICLE ACCELERATORS; ACCELERATORS; COMMISSIONING; CONSTRUCTION; ELECTRON BEAMS; ELECTRONS; NUCLEAR PHYSICS; ...

  3. Initial experimental evidence of self-collimation of target-normal-sheath-accelerated proton beam in a stack of conducting foils

    SciTech Connect (OSTI)

    Ni, P. A.; Bieniosek, F. M.; Logan, B. G.; Lund, S. M.; Barnard, J. J.; Bellei, C.; Cohen, R. H.; McGuffey, C.; Beg, F. N.; Kim, J.; Alexander, N.; Aurand, B.; Brabetz, C.; Neumayer, P.; Roth, M.

    2013-08-15

    Phenomena consistent with self-collimation (or weak self-focusing) of laser target-normal-sheath-accelerated protons was experimentally observed for the first time, in a specially engineered structure (lens) consisting of a stack of 300 thin aluminum foils separated by 50 ?m vacuum gaps. The experiments were carried out in a passive environment, i.e., no external fields applied, neutralization plasma or injection of secondary charged particles was imposed. Experiments were performed at the petawatt PHELIX laser user facility (E = 100 J, ?t = 400 fs, ? = 1062 nm) at the Helmholtzzentrum fr SchwerionenforschungGSI in Darmstadt, Germany. The observed rms beam spot reduction depends inversely on energy, with a focusing degree decreasing monotonically from 2 at 5.4 MeV to 1.5 at 18.7 MeV. The physics inside the lens is complex, resulting in a number of different mechanisms that can potentially affect the particle dynamics within the structure. We present a plausible simple interpretation of the experiment in which the combination of magnetic self-pinch forces generated by the beam current together with the simultaneous reduction of the repulsive electrostatic forces due to the foils are the dominant mechanisms responsible for the observed focusing/collimation. This focusing technique could be applied to a wide variety of space-charge dominated proton and heavy ion beams and impact fields and applications, such as HEDP science, inertial confinement fusion in both fast ignition and heavy ion fusion approaches, compact laser-driven injectors for a Linear Accelerator (LINAC) or synchrotron, medical therapy, materials processing, etc.

  4. Depolarization due to beam-beam interaction in electron-positron...

    Office of Scientific and Technical Information (OSTI)

    EQUATIONS; INTERACTIONS; LEPTON-LEPTON INTERACTIONS; LINEAR ACCELERATORS; PARTIAL DIFFERENTIAL EQUATIONS; PARTICLE INTERACTIONS 430200* -- Particle Accelerators-- Beam Dynamics, ...

  5. Charged particle accelerator grating

    DOE Patents [OSTI]

    Palmer, Robert B.

    1986-09-02

    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.

  6. Charged particle accelerator grating

    DOE Patents [OSTI]

    Palmer, Robert B.

    1986-01-01

    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.

  7. A study of the effect of in-line and perpendicular magnetic fields on beam characteristics of electron guns in medical linear accelerators

    SciTech Connect (OSTI)

    Constantin, Dragos E.; Fahrig, Rebecca; Keall, Paul J.

    2011-07-15

    Purpose: Using magnetic resonance imaging (MRI) for real-time guidance during radiotherapy is an active area of research and development. One aspect of the problem is the influence of the MRI scanner, modeled here as an external magnetic field, on the medical linear accelerator (linac) components. The present work characterizes the behavior of two medical linac electron guns with external magnetic fields for in-line and perpendicular orientations of the linac with respect to the MRI scanner. Methods: Two electron guns, Litton L-2087 and Varian VTC6364, are considered as representative models for this study. Emphasis was placed on the in-line design approach in which case the MRI scanner and the linac axes of symmetry coincide and assumes no magnetic shielding of the linac. For the in-line case, the magnetic field from a 0.5 T open MRI (GE Signa SP) magnet with a 60 cm gap between its poles was computed and used in full three dimensional (3D) space charge simulations, whereas for the perpendicular case the magnetic field was constant. Results: For the in-line configuration, it is shown that the electron beam is not deflected from the axis of symmetry of the gun and the primary beam current does not vanish even at very high values of the magnetic field, e.g., 0.16 T. As the field strength increases, the primary beam current has an initial plateau of constant value after which its value decreases to a minimum corresponding to a field strength of approximately 0.06 T. After the minimum is reached, the current starts to increase slowly. For the case when the beam current computation is performed at the beam waist position the initial plateau ends at 0.016 T for Litton L-2087 and at 0.012 T for Varian VTC6364. The minimum value of the primary beam current is 27.5% of the initial value for Litton L-2087 and 22.9% of the initial value for Varian VTC6364. The minimum current is reached at 0.06 and 0.062 T for Litton L-2087 and Varian VTC6364, respectively. At 0.16 T the

  8. Simulation of Weibel Instability for LWFA and PWFA Electron Beams

    SciTech Connect (OSTI)

    Allen, B.; Muggli, P.; Feng, B.; Katsouleas, T.; Huang, C.; Yakimenko, V.; Maksimchuk, A.

    2009-01-22

    Weibel instability is of central importance for relativistic beams both in laboratory, ex. fast-igniter concept for inertial confinement fusion, and astrophysical, ex. cosmic jets, plasmas. Simulations, using QuickPIC, of an intense and monoenergetic beam propagating through a plasma were conducted for experimental setups with Laser Wakefield and RF accelerators and show the appearance of Weibel instability (or current instability). The appearance of the instability is investigated as a function of beam parameters (density, spot size and bunch length) and plasma parameters (plasma density and length of plasma). We present preliminary simulation results that show that the instability should be observable for the RF accelerator experiment.

  9. Fermilab | Tevatron | Accelerator

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

    Accelerator photo Fermilab is home to the Tevatron, once the most powerful particle accelerator in the United States and the second most powerful particle accelerator in the world. The Tevatron was the second most powerful particle accelerator in the world before it shut down on Sept. 29, 2011. It accelerated beams of protons and antiprotons to 99.999954 percent of the speed of light around a four-mile circumference. The two beams collided at the centers of two 5,000-ton detectors positioned

  10. Progress on the realization of a new GEM based neutron diagnostic concept for high flux neutron beams

    SciTech Connect (OSTI)

    Croci, G.; Tardocchi, M.; Rebai, M.; Cippo, E. Perelli; Gorini, G.; Cazzaniga, C.; Palma, M. Dalla; Pasqualotto, R.; Tollin, M.; Grosso, G.; Muraro, A.; Murtas, F.; Claps, G.; Cavenago, M.

    2014-08-21

    Fusion reactors will need high flux neutron detectors to diagnose the deuterium-deuterium and deuterium-tritium. A candidate detection technique is the Gas Electron Multiplier (GEM). New GEM based detectors are being developed for application to a neutral deuterium beam test facility. The proposed detection system is called Close-contact Neutron Emission Surface Mapping (CNESM). The diagnostic aims at providing the map of the neutron emission due to interaction of the deuterium beam with the deuterons implanted in the beam dump surface. This is done by placing a detector in close contact, right behind the dump. CNESM uses nGEM detectors, i.e. GEM detectors equipped with a cathode that also serves as neutron-proton converter foil. After the realization and test of several small area prototypes, a full size prototype has been realized and tested with laboratory sources. Test on neutron beams are foreseen for the next months.

  11. Experimental results of an electron cyclotron resonance oxygen source and a low energy beam transport system for 1 MeV integral split ring radio frequency quadruple accelerator upgrade project

    SciTech Connect (OSTI)

    Peng, S. X.; Zhang, M.; Song, Z. Z.; Xu, R.; Zhao, J.; Yuan, Z. X.; Yu, J. X.; Chen, J.; Guo, Z. Y.

    2008-02-15

    To meet the requirements of developing separated function radio frequency quadruple (rfq) and upgrading the 1 MeV integral split ring rfq accelerator, an electron cyclotron resonance O{sup +} ion source and low energy beam transport (LEBT) system have been developed. Using two Einzel lenses to focus the beam, more than 6 mA O{sup +} peak beam current with energy of 22 keV can be easily obtained at the end of LEBT when the duty faction is at 1/6. The normalized root-mean-square emittance of 90% of the beam is about 0.12{pi} mm mrad. By changing the focusing power of lenses, the beam waist can be shifted from 80 mm before the beam diaphragm 2 to 80 mm after it. The experimental results will be presented in this article.

  12. Proton Acceleration: New Developments in Energy Increase, Focusing...

    Office of Scientific and Technical Information (OSTI)

    ... Country of Publication: United States Language: English Subject: 43 PARTICLE ACCELERATORS; ACCELERATION; ACCELERATORS; BRIGHTNESS; FOCUSING; ION BEAMS; ION SOURCES; LASERS; PLASMA; ...

  13. Hosing Instability of the Drive Electron Beam in the E157 Plasma...

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: USDOE Country of Publication: United States Language: English Subject: 43 PARTICLE ACCELERATORS; ACCELERATION; ACCELERATORS; ELECTRON BEAMS; ELECTRONS; HOSE ...

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

    SciTech Connect (OSTI)

    Shiltsev, V.; Piot, P.

    2013-09-01

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

  15. Control and manipulation of electron beams

    SciTech Connect (OSTI)

    Piot, Philippe; /NICADD, DeKalb /Northern Illinois U. /Fermilab

    2008-09-01

    The concepts of the advanced accelerators and light source rely on the production of bright electron beams. The rms areas of the beam phase space often need to be tailored to the specific applications. Furthermore, a new class of the forefront research calls for detailed specific distribution such as the particle density in the time coordinate. Several groups are tackling these various challenges and in this report we attempt to give a review of the state-of-the-art of the control and manipulation of the electron beams.

  16. Polarized Proton Acceleration in AGS and RHIC (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Subject: 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ACCELERATION; BEAM PRODUCTION; BROOKHAVEN RHIC; DEPOLARIZATION; GEV RANGE; POLARIZATION; POLARIZED BEAMS; PROTON BEAMS; ...

  17. Accelerator Science | Jefferson Lab

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

    Accelerator Science Jefferson Lab is recognized as a world leader in accelerator science. This expertise comes from the planning, building, maintaining and operating of the Continuous Electron Beam Accelerator Facility (CEBAF) - the lab's particle accelerator. CEBAF is based on superconducting radiofrequency (SRF) technology. It produces a stream of charged electrons that scientists use to probe the nucleus of the atom. CEBAF was the first large-scale application of SRF technology in the world,

  18. Tevatron accelerator physics and operation highlights

    SciTech Connect (OSTI)

    Valishev, A.; /Fermilab

    2011-03-01

    The performance of the Tevatron collider demonstrated continuous growth over the course of Run II, with the peak luminosity reaching 4 x 10{sup 32} cm{sup -2} s{sup -1}, and the weekly integration rate exceeding 70 pb{sup -1}. This report presents a review of the most important advances that contributed to this performance improvement, including beam dynamics modeling, precision optics measurements and stability control, implementation of collimation during low-beta squeeze. Algorithms employed for optimization of the luminosity integration are presented and the lessons learned from high-luminosity operation are discussed. Studies of novel accelerator physics concepts at the Tevatron are described, such as the collimation techniques using crystal collimator and hollow electron beam, and compensation of beam-beam effects.

  19. The CAMS Accelerator Facility

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

    the cams accelerator facility The CAMS Accelerator Facility Today CAMS's primary facility is a ~10,000 ft2 building that houses three state-of-the-art, accelerator-based technologies. Upper Left: The HVEC 10 MV Model FN Tandem Van de Graaff Accelerator and the lighter-ion AMS beamline. Upper Right: The NEC 1.0 MV Model 3SDH-1 Tandem Accelerator for BioAMS. Lower: The NEC 1.7 MV Model 5SDH-2 Tandem Accelerator for Ion Beam Analysis and neutron production. CAMS' principal research instrument is a

  20. GPU accelerated fully space and time resolved numerical simulations of self-focusing laser beams in SBS-active media

    SciTech Connect (OSTI)

    Mauger, Sarah; Colin de Verdière, Guillaume; Bergé, Luc; Skupin, Stefan; Friedrich Schiller University, Institute of Condensed Matter Theory and Optics, 07743 Jena

    2013-02-15

    A computer cluster equipped with Graphics Processing Units (GPUs) is used for simulating nonlinear optical wave packets undergoing Kerr self-focusing and stimulated Brillouin scattering in fused silica. We first recall the model equations in full (3+1) dimensions. These consist of two coupled nonlinear Schrödinger equations for counterpropagating optical beams closed with a source equation for light-induced acoustic waves seeded by thermal noise. Compared with simulations on a conventional cluster of Central Processing Units (CPUs), GPU-based computations allow us to use a significant (16 times) larger number of mesh points within similar computation times. Reciprocally, simulations employing the same number of mesh points are between 3 and 20 times faster on GPUs than on the same number of classical CPUs. Performance speedups close to 45 are reported for isolated functions evaluating, e.g., the optical nonlinearities. Since the field intensities may reach the ionization threshold of silica, the action of a defocusing electron plasma is also addressed.

  1. Linear Accelerator | Advanced Photon Source

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

    Linear Accelerator Producing brilliant x-ray beams at the APS begins with electrons emitted from a cathode heated to 1100 C. The electrons are accelerated by high-voltage...

  2. SSRL Accelerator Phycics Home Page

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

    at.gif (15297 bytes) BeamOptics.gif (29047 bytes) ICFA2000t.gif (31362 bytes) Home Page LCLS Accelerator Physics at SSRL The field tha t can be covered by the Accelerator Physics...

  3. Compact accelerator for medical therapy

    DOE Patents [OSTI]

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

    2010-05-04

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

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

    SciTech Connect (OSTI)

    Arntz, Floyd; Kardo-Sysoev, A.; Krasnykh, A.; /SLAC

    2008-12-16

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

  5. Fermilab | Illinois Accelerator Research Center | More Information

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

    More Information General Office of Partnerships and Technology Transfer Illinois Department of Commerce and Economic Opportunity Department of Energy Advanced Superconductor Test Accelerator Accelerator Applications 4th Edition, "Accelerators and Beams, Tools of Discovery and Innovation"

  6. Sequentially pulsed traveling wave accelerator

    DOE Patents [OSTI]

    Caporaso, George J.; Nelson, Scott D.; Poole, Brian R.

    2009-08-18

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

  7. Beam Dynamics for ARIA

    SciTech Connect (OSTI)

    Ekdahl, Carl August Jr.

    2014-10-14

    Beam dynamics issues are assessed for a new linear induction electron accelerator being designed for flash radiography of large explosively driven hydrodynamic experiments. Special attention is paid to equilibrium beam transport, possible emittance growth, and beam stability. It is concluded that a radiographic quality beam will be produced possible if engineering standards and construction details are equivalent to those on the present radiography accelerators at Los Alamos.

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

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

    Accelerator Fermilab Accelerator Science and Technology Facility photo The Fermilab Accelerator Science and Technology (FAST) Facility is America's only test bed for cutting-edge, record high-intensity particle beams and for accelerator research aimed at intensity frontier proton accelerators. FAST will also be unique in the United States as a particle beam research facility based on superconducting radio-frequency technology, on which nearly all proposed future accelerators in the world are

  9. Accelerator Science

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

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

  10. PULSED-FOCUSING RECIRCULATING LINACS FOR MUON ACCELERATION

    SciTech Connect (OSTI)

    Johnson, Rolland PAUL

    2014-12-31

    two. A patent application was filed for this invention and a detailed report published in Physical Review Special Topics. A scaled model using an electron beam was developed and proposed to test the concept of a dog bone RLA with combined-function return arcs. The efforts supported by this grant were reported in a series of contributions to particle accelerator conferences that are reproduced in the appendices and summarized in the body of this report.

  11. Betatron Radiation from a Beam Driven Plasma Source Litos, M...

    Office of Scientific and Technical Information (OSTI)

    Betatron Radiation from a Beam Driven Plasma Source Litos, M.; Corde, S.; SLAC 43 PARTICLE ACCELERATORS; ACCELERATION; ACCELERATORS; BETATRON OSCILLATIONS; BETATRONS;...

  12. BEAM INSTRUMENTATION FOR HIGH POWER HADRON BEAMS

    SciTech Connect (OSTI)

    Aleksandrov, Alexander V

    2013-01-01

    This presentation will describe developments in the beam diagnostics which support the understanding and operation of high power hadron accelerators. These include the measurement of large dynamic range transverse and longitudinal beam profiles, beam loss detection, and non-interceptive diagnostics.

  13. Beam Trail Tracking at Fermilab

    SciTech Connect (OSTI)

    Nicklaus, Dennis J.; Carmichael, Linden Ralph; Neswold, Richard; Yuan, Zongwei

    2015-01-01

    We present a system for acquiring and sorting data from select devices depending on the destination of each particular beam pulse in the Fermilab accelerator chain. The 15 Hz beam that begins in the Fermilab ion source can be directed to a variety of additional accelerators, beam lines, beam dumps, and experiments. We have implemented a data acquisition system that senses the destination of each pulse and reads the appropriate beam intensity devices so that profiles of the beam can be stored and analysed for each type of beam trail. We envision utilizing this data long term to identify trends in the performance of the accelerators

  14. A measurement of hadron production cross sections for the simulation of accelerator neutrino beams and a search for muon-neutrino to electron-neutrino oscillations in the delta m**2 about equals 1-eV**2 region

    SciTech Connect (OSTI)

    Schmitz, David W.; /Columbia U.

    2008-01-01

    A measurement of hadron production cross-sections for the simulation of accelerator neutrino beams and a search for muon neutrino to electron neutrino oscillations in the {Delta}m{sup 2} {approx} 1 eV{sup 2} region. This dissertation presents measurements from two different high energy physics experiments with a very strong connection: the Hadron Production (HARP) experiment located at CERN in Geneva, Switzerland, and the Mini Booster Neutrino Experiment (Mini-BooNE) located at Fermilab in Batavia, Illinois.

  15. Fermilab | Illinois Accelerator Research Center | Fermilab Core

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

    Capabilities Core Capabilities photo Core capabilities Areas of Expertise Accelerator Science Beam dynamics and theory Design of linear and circular accelerators Simulation and Modeling Phase-space manipulation Energy Deposition Accelerator Operation Operation and commissioning of large, complex accelerator systems Accelerator Technology (design, fabrication, test) Particle sources Superconducting RF cavities and Cryomodules Conventional magnets Pulsed magnets and kickers Superconducting

  16. Charged particle accelerator grating

    DOE Patents [OSTI]

    Palmer, R.B.

    1985-09-09

    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.

  17. High brightness electron accelerator

    DOE Patents [OSTI]

    Sheffield, Richard L.; Carlsten, Bruce E.; Young, Lloyd M.

    1994-01-01

    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.

  18. Accelerator physics and modeling: Proceedings

    SciTech Connect (OSTI)

    Parsa, Z.

    1991-12-31

    This report contains papers on the following topics: Physics of high brightness beams; radio frequency beam conditioner for fast-wave free-electron generators of coherent radiation; wake-field and space-charge effects on high brightness beams. Calculations and measured results for BNL-ATF; non-linear orbit theory and accelerator design; general problems of modeling for accelerators; development and application of dispersive soft ferrite models for time-domain simulation; and bunch lengthening in the SLC damping rings.

  19. Accelerator physics and modeling: Proceedings

    SciTech Connect (OSTI)

    Parsa, Z.

    1991-01-01

    This report contains papers on the following topics: Physics of high brightness beams; radio frequency beam conditioner for fast-wave free-electron generators of coherent radiation; wake-field and space-charge effects on high brightness beams. Calculations and measured results for BNL-ATF; non-linear orbit theory and accelerator design; general problems of modeling for accelerators; development and application of dispersive soft ferrite models for time-domain simulation; and bunch lengthening in the SLC damping rings.

  20. Imaging Techniques for Relativistic Beams: Issues and Limitations

    SciTech Connect (OSTI)

    Lumpkin, Alex H.; Wendt, Manfred; /Fermilab

    2012-02-01

    Characterizations of transverse profiles for low-power beams in the accelerators of the proposed linear colliders (ILC and CLIC) using imaging techniques are being evaluated. Assessments of the issues and limitations for imaging relativistic beams with intercepting scintillator or optical transition radiation screens are presented based on low-energy tests at the Fermilab A0 photoinjector and are planned for the Advanced Superconducting Test Accelerator at Fermilab. We have described several of the issues and limitations one encounters with the imaging of relativistic electron beams. We have reported our initial tests at the A0PI facility and our plans to extend these studies to the GeV scale at the ASTA facility. We also have plans to test these concepts with 23-GeV beams at the FACET facility at SLAC in the coming year. It appears the future remains bright for imaging techniques in ILC-relevant parameter space.

  1. Adaptive control for accelerators

    DOE Patents [OSTI]

    Eaton, Lawrie E.; Jachim, Stephen P.; Natter, Eckard F.

    1991-01-01

    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.

  2. Plasma research shows promise for future compact accelerators

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

    Plasma research shows promise for future compact accelerators Plasma research shows promise for future compact accelerators A transformative breakthrough in controlling ion beams ...

  3. The Muon Accelerator Program (Journal Article) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: DOE Office of Science Country of Publication: United States Language: English Subject: 43 PARTICLE ACCELERATORS; ACCELERATORS; LUMINOSITY; MUONS; NEUTRINO BEAMS; ...

  4. Novel Slow Extraction Scheme for Proton Accelerators Using Pulsed...

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: DOE Office of Science Country of Publication: United States Language: English Subject: 43 PARTICLE ACCELERATORS; ACCELERATORS; BEAM DYNAMICS; DIPOLES; EFFICIENCY; ...

  5. DEVELOPMENT OF ACCELERATOR DATA REPORTING SYSTEM AND ITS APPLICATION...

    Office of Scientific and Technical Information (OSTI)

    DEVELOPMENT OF ACCELERATOR DATA REPORTING SYSTEM AND ITS APPLICATION TO TREND ANALYSIS OF BEAM CURRENT DATA Citation Details In-Document Search Title: DEVELOPMENT OF ACCELERATOR ...

  6. Voltage regulation in linear induction accelerators

    DOE Patents [OSTI]

    Parsons, William M.

    1992-01-01

    Improvement in voltage regulation in a Linear Induction Accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance.

  7. Voltage regulation in linear induction accelerators

    DOE Patents [OSTI]

    Parsons, W.M.

    1992-12-29

    Improvement in voltage regulation in a linear induction accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core is disclosed. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance. 4 figs.

  8. Five-Year Outcomes, Cosmesis, and Toxicity With 3-Dimensional Conformal External Beam Radiation Therapy to Deliver Accelerated Partial Breast Irradiation

    SciTech Connect (OSTI)

    Rodrguez, Nria; Sanz, Xavier; Dengra, Josefa; Foro, Palmira; Membrive, Ismael; Reig, Anna; Quera, Jaume; Fernndez-Velilla, Enric; Pera, scar; Lio, Jackson; Lozano, Joan; Algara, Manuel

    2013-12-01

    Purpose: To report the interim results from a study comparing the efficacy, toxicity, and cosmesis of breast-conserving treatment with accelerated partial breast irradiation (APBI) or whole breast irradiation (WBI) using 3-dimensional conformal external beam radiation therapy (3D-CRT). Methods and Materials: 102 patients with early-stage breast cancer who underwent breast-conserving surgery were randomized to receive either WBI (n=51) or APBI (n=51). In the WBI arm, 48 Gy was delivered to the whole breast in daily fractions of 2 Gy, with or without additional 10 Gy to the tumor bed. In the APBI arm, patients received 37.5 Gy in 3.75 Gy per fraction delivered twice daily. Toxicity results were scored according to the Radiation Therapy Oncology Group Common Toxicity Criteria. Skin elasticity was measured using a dedicated device (Multi-Skin-Test-Center MC-750-B2, CKelectronic-GmbH). Cosmetic results were assessed by the physician and the patients as good/excellent, regular, or poor. Results: The median follow-up time was 5 years. No local recurrences were observed. No significant differences in survival rates were found. APBI reduced acute side effects and radiation doses to healthy tissues compared with WBI (P<.01). Late skin toxicity was no worse than grade 2 in either group, without significant differences between the 2 groups. In the ipsilateral breast, the areas that received the highest doses (ie, the boost or quadrant) showed the greatest loss of elasticity. WBI resulted in a greater loss of elasticity in the high-dose area compared with APBI (P<.05). Physician assessment showed that >75% of patients in the APBI arm had excellent or good cosmesis, and these outcomes appear to be stable over time. The percentage of patients with excellent/good cosmetic results was similar in both groups. Conclusions: APBI delivered by 3D-CRT to the tumor bed for a selected group of early-stage breast cancer patients produces 5-year results similar to those achieved with

  9. Fermilab | Illinois Accelerator Research Center | Accelerators and Society

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

    Accelerators and Society Physicists have been inventing new types of accelerators to propel charged particles to higher and higher energies for more than 80 years. Today, besides their role in scientific discovery, scientists estimate that more than 30,000 accelerators are at work worldwide in areas ranging from diagnosing and treating disease to powering industrial processes. The accelerators of tomorrow promise still greater opportunities. Next-generation particle beams represent cheaper,

  10. Resolution study of higher-order-mode-based beam position diagnostics using custom-built electronics in strongly coupled 3.9-GHz multi-cavity accelerating module

    SciTech Connect (OSTI)

    Zhang, P.; Baboi, N.; Jones, R.M.; Eddy, N.

    2012-11-01

    Beam-excited higher order modes (HOMs) can provide remote diagnostics information of the beam position and cavity misalignment. In this paper we report on recent studies on the resolution with specially selected series of modes with custom-built electronics. This constitutes the first report of measurements of these cavities in which we obtained a resolution of 20 micron in beam offset. Details of the setup of the electronics and HOM measurements are provided.

  11. Formation of compressed flat electron beams with high transverse-emittance ratios

    SciTech Connect (OSTI)

    Zhu, J.; Piot, P.; Mihalcea, D.; Prokop, C. R.

    2014-08-01

    Flat beamsbeams with asymmetric transverse emittanceshave important applications in novel light-source concepts and advanced-acceleration schemes and could possibly alleviate the need for damping rings in lepton colliders. Over the last decade, a flat beam generation technique based on the conversion of an angular-momentum-dominated beam was proposed and experimentally tested. In this paper we explore the production of compressed flat beams. We especially investigate and optimize the flat beam transformation for beams with substantial fractional energy spread. We use as a simulation example the photoinjector of Fermilabs Advanced Superconducting Test Accelerator. The optimizations of the flat beam generation and compression at Advanced Superconducting Test Accelerator were done via start-to-end numerical simulations for bunch charges of 3.2 nC, 1.0 nC, and 20 pC at ?37??MeV. The optimized emittances of flat beams with different bunch charges were found to be 0.25???m (emittance ratio is ?400), 0.13????m, 15 nm before compression, and 0.41???m, 0.20???m, 16 nm after full compression, respectively, with peak currents as high as 5.5 kA for a 3.2?nC flat beam. These parameters are consistent with requirements needed to excite wakefields in asymmetric dielectric-lined waveguides or produce significant photon flux using small-gap micro-undulators.

  12. The Dielectric Wall Accelerator

    SciTech Connect (OSTI)

    Caporaso, George J.; Chen, Yu-Jiuan; Sampayan, Stephen E.

    2009-01-01

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

  13. Cascaded target normal sheath acceleration

    SciTech Connect (OSTI)

    Wang, W. P.; Shen, B. F.; Zhang, X. M.; Wang, X. F.; Xu, J. C.; Zhao, X. Y.; Yu, Y. H.; Yi, L. Q.; Shi, Y.; Zhang, L. G.; Xu, T. J.; Xu, Z. Z.

    2013-11-15

    A cascaded target normal sheath acceleration (TNSA) scheme is proposed to simultaneously increase energy and improve energy spread of a laser-produced mono-energetic proton beam. An optimum condition that uses the maximum sheath field to accelerate the center of the proton beam is theoretically found and verified by two-dimensional particle-in-cell simulations. An initial 10 MeV proton beam is accelerated to 21 MeV with energy spread decreased from 5% to 2% under the optimum condition during the process of the cascaded TNSA. The scheme opens a way to scale proton energy lineally with laser energy.

  14. A table-top x-ray FEL based on a laser wakefield accelerator-undulator system

    SciTech Connect (OSTI)

    Nakajima, K.; Kawakubo, T.; Nakanishi, H.

    1995-12-31

    Ultrahigh-gradient electron acceleration has been confirmed owing to the laser wakefield acceleration mechanism driven by an intense short laser wakefield acceleration mechanism driven by an intense short laser pulse in an underdense plasma. The laser wakefield acceleration makes it possible to build a compact electron linac capable of producing an ultra-short bunched electron beam. While the accelerator is attributed to longitudinal wakefields, transverse wakefields simultaneously generated by a short laser pulse can serve as a plasma undulator with a very short wavelength equal to a half of the plasma wavelength. We propose a new FEL concept for X-rays based on a laser wakefield accelerator-undulator system driven by intense short laser pulses delivered from table-top terawatt lasers. The system is composed of the accelerator stage and the undulator stage in a table-top size. A low energy electron beam is accelerated an bunched into microbunches due to laser wakefields in the accelerator stage. A micro-bunched beam travelling to the opposite direction of driving laser pulses produces coherent X-ray radiation in the undulator stage. A practical configuration and its analyses are presented.

  15. Variable energy constant current accelerator structure

    DOE Patents [OSTI]

    Anderson, O.A.

    1988-07-13

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

  16. PARTICLE BEAM TRACKING CIRCUIT

    DOE Patents [OSTI]

    Anderson, O.A.

    1959-05-01

    >A particle-beam tracking and correcting circuit is described. Beam induction electrodes are placed on either side of the beam, and potentials induced by the beam are compared in a voltage comparator or discriminator. This comparison produces an error signal which modifies the fm curve at the voltage applied to the drift tube, thereby returning the orbit to the preferred position. The arrangement serves also to synchronize accelerating frequency and magnetic field growth. (T.R.H.)

  17. Beam tuning

    SciTech Connect (OSTI)

    Pardo, R.C.; Zinkann, G.P.

    1995-08-01

    A program for configuring the linac, based on previously run configurations for any desired beam was used during the past year. This program uses only a small number of empirical tunes to scale resonator fields to properly accelerate a beam with a different charge-to-mass (q/A) ratio from the original tune configuration. The program worked very well for the PII linac section where we can easily match a new beam`s arrival phase and velocity to the tuned value. It was also fairly successful for the Booster and ATLAS sections of the linac, but not as successful as for the PII linac. Most of the problems are associated with setting the beam arrival time correctly for each major linac section. This problem is being addressed with the development of the capacitive pickup beam phase monitor discussed above. During the next year we expect to improve our ability to quickly configure the linac for new beams and reduce the time required for linac tuning. Already the time required for linac tuning as a percentage of research hours has decreased from 22% in FY 1993 to 15% in the first quarter of FY 1995.

  18. In-beam Mssbauer spectroscopy of {sup 57}Fe/{sup 57}Mn in MgO and NaF at Heavy-Ion Medical Accelerator in Chiba

    SciTech Connect (OSTI)

    Kubo, M. K.; Kobayashi, Y.; Yamada, Y.; Mihara, M.; Nagatomo, T.; Sato, W.; Miyazaki, J.; Sato, S.; Kitagawa, A.

    2014-02-15

    Development of efficient ion supply of {sup 58}Fe from {sup 58}Fe(C{sub 5}H{sub 5}){sub 2}, and quick switching between therapy and material science at the Heavy-Ion Medical Accelerator in Chiba realized a new {sup 57}Mn in-beam emission Mssbauer spectroscopy measurement system. Application to simple binary chemical compounds, MgO and NaF, proved the usefulness of the system to probe chemical and physical behaviors of trace impurities in solids. Annealing of lattice defects produced by the implantation and ?-decay of {sup 57}Mn and/or ?-ray emission recoil was observed by a local probe.

  19. Accelerator Technology Division annual report, FY 1989

    SciTech Connect (OSTI)

    Not Available

    1990-06-01

    This paper discusses: accelerator physics and special projects; experiments and injectors; magnetic optics and beam diagnostics; accelerator design and engineering; radio-frequency technology; accelerator theory and simulation; free-electron laser technology; accelerator controls and automation; and high power microwave sources and effects.

  20. Emittance preservation during bunch compression with a magnetized beam

    SciTech Connect (OSTI)

    Stratakis, Diktys

    2015-09-02

    The deleterious effects of coherent synchrotron radiation (CSR) on the phase-space and energy spread of high-energy beams in accelerator light sources can significantly constrain the machine design and performance. In this paper, we present a simple method to preserve the beam emittance by means of using magnetized beams that exhibit a large aspect ratio on their transverse dimensions. The concept is based on combining a finite solenoid field where the beam is generated together with a special optics adapter. Numerical simulations of this new type of beam source show that the induced phase-space density growth can be notably suppressed to less than 1% for any bunch charge. This work elucidates the key parameters that are needed for emittance preservation, such as the required field and aspect ratio for a given bunch charge.

  1. Photodetachment process for beam neutralization

    DOE Patents [OSTI]

    Fink, J.H.; Frank, A.M.

    1979-02-20

    A process for neutralization of accelerated ions employing photo-induced charge detachment is disclosed. The process involves directing a laser beam across the path of a negative ion beam such as to effect photodetachment of electrons from the beam ions. The frequency of the laser beam employed is selected to provide the maximum cross-section for the photodetachment process. 2 figs.

  2. Accelerators for Testing Radiation Tolerances of Electronics...

    Office of Science (SC) Website

    Accelerated beams test semiconductor devices for tolerances to space radiation. ... The ability to test in air makes it possible to quickly change components and to easily ...

  3. PEPPo: Using a Polarized Electron Beam to Produce Polarized Positrons

    SciTech Connect (OSTI)

    Adeyemi, Adeleke H.

    2015-09-01

    Polarized positron beams have been identified as either an essential or a significant ingredient for the experimental program of both the present and next generation of lepton accelerators (JLab, Super KEK B, ILC, CLIC). An experiment demonstrating a new method for producing polarized positrons has been performed at the Continuous Electron Beam Accelerator Facility at Jefferson Lab. The PEPPo (Polarized Electrons for Polarized Positrons) concept relies on the production of polarized e-/e+ pairs from the bremsstrahlung radiation of a longitudinally polarized electron beam interacting within a high Z conversion target. PEPPo demonstrated the effective transfer of spin-polarization of an 8.2 MeV/c polarized (P~85%) electron beam to positrons produced in varying thickness tungsten production targets, and collected and measured in the range of 3.1 to 6.2 MeV/c. In comparison to other methods this technique reveals a new pathway for producing either high energy or thermal polarized positron beams using a relatively low polarized electron beam energy (~10MeV) .This presentation will describe the PEPPo concept, the motivations of the experiment and high positron polarization achieved.

  4. Report on Workshop on Future Directions for Accelerator R&D at Fermilab

    SciTech Connect (OSTI)

    Shiltsev, V.; Church, M.; Spentzouris, P.; Chou, W.; /Fermilab

    2009-09-01

    Accelerator R&D has played a crucial role in enabling scientific discovery in the past century and will continue to play this role in the years to come. In the U.S., the Office of High Energy Physics of DOE's Office of Science is developing a plan for national accelerator R&D stewardship. Fermilab undertakes accelerator research, design, and development focused on superconducting radio-frequency (RF), superconducting magnet, beam cooling, and high intensity proton technologies. In addition, the Lab pursues comprehensive integrated theoretical concepts and simulations of complete future facilities on both the energy and intensity frontiers. At present, Fermilab (1) supplies integrated design concept and technology development for a multi-MW proton source (Project X) to support world-leading programs in long baseline neutrino and rare processes experiments; (2) plays a leading role in the development of ionization cooling technologies required for muon storage ring facilities at the energy (multi-TeV Muon Collider) and intensity (Neutrino Factory) frontiers, and supplies integrated design concepts for these facilities; and (3) carries out a program of advanced accelerator R&D (AARD) in the field of high quality beam sources, and novel beam manipulation techniques.

  5. Fifteen Years of Beam on Target | Jefferson Lab

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

    Fifteen Years of Beam on Target Fifteen Years of Beam on Target First beam enters Hall C First beam enters Hall C. On July 1, 1994, Jefferson Lab's accelerator delivered an ...

  6. Beam! Magic! | Jefferson Lab

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

    with all the changes, the accelerator can be made to work. Beam Since my first serious introduction to nuclear and particle physics - when I worked for a few weeks one summer at...

  7. Beam Status

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

    Beam Status Beam Status Print Loading... You can also view the Operations Group's Beam History archives.

  8. COMPARATIVE STUDIES OF PROTON ACCELERATORS FOR HIGH POWER APPLICATIONS.

    SciTech Connect (OSTI)

    WENG, W.T.

    2006-05-29

    There are many applications requiring high power proton accelerators of various kinds. However, each type of proton accelerator can only provide beam with certain characteristics, hence the match of accelerators and their applications need careful evaluation. In this talk, the beam parameters and performance limitations of linac, cyclotron, synchrotron, and FFAG accelerators are studied and their relative merits for application in neutron, muon, neutrino, and ADS will be assessed in terms of beam energy, intensity, bunch length, repetition rate, and beam power requirements. A possible match between the applications and the accelerator of choice is presented in a matrix form. The accelerator physics and technology issues and challenges involved will also be discussed.

  9. Generation and pointing stabilization of multi-GeV electron beams from a laser plasma accelerator driven in a pre-formed plasma waveguide

    SciTech Connect (OSTI)

    Gonsalves, A. J.; Nakamura, K.; Daniels, J.; Mao, H.-S.; Benedetti, C.; Schroeder, C. B.; Tóth, Cs.; Tilborg, J. van; Vay, J.-L.; Geddes, C. G. R.; Esarey, E.; Mittelberger, D. E.; Bulanov, S. S.; Leemans, W. P.

    2015-05-15

    Laser pulses with peak power 0.3 PW were used to generate electron beams with energy >4 GeV within a 9 cm-long capillary discharge waveguide operated with a plasma density of ≈7×10{sup 17} cm{sup −3}. Simulations showed that the super-Gaussian near-field laser profile that is typical of high-power femtosecond laser systems reduces the efficacy of guiding in parabolic plasma channels compared with the Gaussian laser pulses that are typically simulated. In the experiments, this was mitigated by increasing the plasma density and hence the contribution of self-guiding. This allowed for the generation of multi-GeV electron beams, but these had angular fluctuation ≳2 mrad rms. Mitigation of capillary damage and more accurate alignment allowed for stable beams to be produced with energy 2.7±0.1 GeV. The pointing fluctuation was 0.6 mrad rms, which was less than the beam divergence of ≲1 mrad full-width-half-maximum.

  10. Accelerator research studies

    SciTech Connect (OSTI)

    Not Available

    1993-01-01

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