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Sample records for cebaf accelerator

  1. CEBAF Accelerator Achievements

    International Nuclear Information System (INIS)

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

    2011-01-01

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

  2. CEBAF

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1992-09-15

    Installation is well underway for the first of the two main superconducting linacs for the Continuous Electron Beam Accelerating Facility (CEBAF) in Newport News, Virginia. With first physics scheduled to start in Spring 1994, CEBAF's science will use intense continuous electron beams of up to about 6 GeV to explore the middle ground between conventional nuclear physics, viewing the nucleus as a bound state of protons and neutrons, and the particle physics picture of nucleons as assemblies of quarks and gluons. With this nuclearparticle interface not well understood, the CEBAF physics programme could go on to reveal important new insights.

  3. CEBAF

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    Installation is well underway for the first of the two main superconducting linacs for the Continuous Electron Beam Accelerating Facility (CEBAF) in Newport News, Virginia. With first physics scheduled to start in Spring 1994, CEBAF's science will use intense continuous electron beams of up to about 6 GeV to explore the middle ground between conventional nuclear physics, viewing the nucleus as a bound state of protons and neutrons, and the particle physics picture of nucleons as assemblies of quarks and gluons. With this nuclearparticle interface not well understood, the CEBAF physics programme could go on to reveal important new insights

  4. CEBAF: Accelerating cavities look good

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1990-09-15

    The first assembled pairs of superconducting accelerating cavities from German supplier Interatom for the Continuous Electron Beam Accelerator Facility, Newport News, Virginia, have exceeded performance specifications.

  5. CEBAF: Accelerating cavities look good

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    The first assembled pairs of superconducting accelerating cavities from German supplier Interatom for the Continuous Electron Beam Accelerator Facility, Newport News, Virginia, have exceeded performance specifications

  6. The CEBAF accelerator and its physics program

    International Nuclear Information System (INIS)

    Cardman, L.S.

    1993-01-01

    The continuous electron beam accelerator facility (CEBAF) consists of a pair of 400 MeV superconducting linacs together with a 5-pass recirculation system and beam switchyard that will permit it to provide three, simultaneous 4 GeV, cw electron beams with a total current of up to 200 μA. The conventional construction for the accelerator and the three experimental end stations is essentially complete. The first linac has been installed in the accelerator tunnel and beam has been accelerated through it; all tests to date have met or exceeded the design specifications. The major components of the experimental equipment for the end stations are under construction. Operation of CEBAF for nuclear physics is scheduled to begin in mid-1994. The facility will support a broad range of nuclear physics research, including topics such as how quarks and gluons are held together in protons and neutrons, the origins of the nuclear force, modifications of nucleons in the nuclear medium, and nuclear structure when nucleons are very close together. The status of the accelerator and its experimental equipment will be presented together with a sampling of experiments planned for the early phases of operation

  7. CEBAF: A superconducting radio frequency accelerator for nuclear physics

    International Nuclear Information System (INIS)

    Hartline, B.K.

    1988-01-01

    The Continuous Electron Beam Accelerator Facility (CEBAF) will be a 4-GeV, 200-μA superconducting recirculating linear accelerator to provide CW electron beams to simultaneous nuclear physics experiments in three end stations. Funded by the Department of Energy, CEBAF's purpose is basic research on the nuclear many-body system, its quark substructure, and the strong and electroweak interactions governing this form of matter. At the heart of the accelerator are niobium superconducting accelerating cavities designed at Cornell University and successfully prototyped with industry during the past three years. The cavities consistently exceed CEBAF's performance specifications (gradient ≥ 5 MV/m, Q 0 ≥ 2.4 /times/ 10 9 at 2 K and 5 MV/m). Construction is under way, and operation is scheduled in 1994. 26 refs., 9 figs., 3 tabs

  8. Integrated on-line accelerator modeling at CEBAF

    International Nuclear Information System (INIS)

    Bowling, B.A.; Shoaee, H.; Van Zeijts, J.; Witherspoon, S.; Watson, W.

    1995-01-01

    An on-line accelerator modeling facility is currently under development at CEBAF. The model server, which is integrated with the EPICS control system, provides coupled and 2nd-order matrices for the entire accelerator, and forms the foundation for automated model- based control and diagnostic applications. Four types of machine models are provided, including design, golden or certified, live, and scratch or simulated model. Provisions are also made for the use of multiple lattice modeling programs such as DIMAD, PARMELA, and TLIE. Design and implementation details are discussed. 2 refs., 4 figs

  9. CEBAF [Continuous Electron Beam Accelerator Facility] design report

    International Nuclear Information System (INIS)

    1986-05-01

    This book describes the conceptual design of, and the planning for, the Continuous Electron Beam Accelerator Facility (CEBAF), which will be a high-intensity, continuous-wave electron linear accelerator (linac) for nuclear physics. Its principal scientific goal is to understand the quark structure, behavior, and clustering of individual nucleons in the nuclear medium, and simultaneously to understand the forces governing this behavior. The linac will consist of 1 GeV of accelerating structure, split into two antiparallel 0.5-GeV segments. The segments will be connected by a beam transport system to circulate the electron beams from one segment to the other for up to four complete passes of acceleration. The maximum beam energy will be 4 GeV at a design current of 200 microamperes. The accelerator complex will also include systems to extract three continuous beams from the linac and to deliver them to three experimental halls equipped with detectors and instrumentation for nuclear physics research. The accelerating structure will be kept superconducting within insulated cryostats filled with liquid helium produced at a central helium refrigerator and distributed to the cryostats via insulated transfer lines. An injector, instrumentation and controls for the accelerator, radio-frequency power systems, and several support facilities will also be provided. A cost estimate based on the Work Breakdown Structure has been completed. Assuming a five-year construction schedule starting early in FY 1987, the total estimated cost is $236 million (actual year dollars), including contingency

  10. CEBAF [Continuous Electron Beam Accelerator Facility] scientific program

    International Nuclear Information System (INIS)

    Gross, F.

    1986-01-01

    The principal scientific mission of the Continuous Electron Beam Facility (CEBAF) is to study collective phenomena in cold (or normal) nucler matter in order to understand the structure and behavior of macroscopic systems constructed from nuclei. This document discusses in broad popular terms those issues which the CEBAF experimental and theoretical program are designed to address. Specific experimental programs currently planned for CEBAF are also reivewed. 35 refs., 19 figs

  11. The CEBAF [Continuous Electron Beam Accelerator Facility] control system architecture

    International Nuclear Information System (INIS)

    Bork, R.

    1987-01-01

    The focus of this paper is on CEBAF's computer control system. This control system will utilize computers in a distributed, networked configuration. The architecture, networking and operating system of the computers, and preliminary performance data are presented. We will also discuss the design of the operator consoles and the interfacing between the computers and CEBAF's instrumentation and operating equipment

  12. Thermionic gun control system for the CEBAF [Continuous Electron Beam Accelerator Facility] injector

    International Nuclear Information System (INIS)

    Pico, R.; Diamond, B.; Fugitt, J.; Bork, R.

    1989-01-01

    The injector for the CEBAF accelerator must produce a high-quality electron beam to meet the overall accelerator specifications. A Hermosa electron gun with a 2 mm-diameter cathode and a control aperture has been chosen as the electron source. This must be controlled over a wide range of operating conditions to meet the beam specifications and to provide flexibility for accelerator commissioning. The gun is controlled using Computer Automated Measurement and Control (CAMAC IEEE-583) technology. The system employs the CAMAC-based control architecture developed at CEBAF. The control system has been tested, and early operating data on the electron gun and the injector beam transport system has been obtained. This system also allows gun parameters to be stored at the operator location, without paralyzing operation. This paper describes the use of this computer system in the control of the CEBAF electron gun. 2 refs., 6 figs., 1 tab

  13. CEBAF/SURA [Continuous Electron Beam Accelerator Facility]/[Southeastern Universities Research Association] 1987 summer workshop

    International Nuclear Information System (INIS)

    Gross, F.; Williamson, C.

    1987-10-01

    This report contains papers from the CEBAF accelerator facility summer workshop. Some topics covered are: baryon-baryon interactions, deuteron form factors; neutron detection; high resolution spectrometers; nuclear strangeness; parity violation; photon-deuteron interactions; chemical reactions in ion sources; quantum chromodynamics; hypernuclear magnetic moments; and photoproduction of π + from 14 N

  14. Survey and analysis of line-frequency interference in the CEBAF accelerator

    International Nuclear Information System (INIS)

    Tiefenback, M.G.; Li, Rui.

    1995-01-01

    Feedthrough of interference from the AC power line into accelerator components is a problem which in pulsed accelerators can be reduced by operation synchronous with the AC line. This means of avoiding line-frequency effects is ineffective for continuous wave machines such as the CEBAF accelerator. We have measured line-frequency perturbations at CEBAF both in beam position and energy by using the beam position monitor system as a multiple-channel sampling oscilloscope. Comparing these data against the measured static optics (taken synchronously with the AC line) we have been able to identify point sources of interference, and resolve line-synchronous variations in the beam energy at a level near 0.001%. 3 refs., 2 figs., 1 tab

  15. The CEBAF [Continuous Electron Beam Accelerator Facility] superconducting accelerator: An overview

    International Nuclear Information System (INIS)

    Leemann, C.W.

    1986-01-01

    The CEBAF accelerator is a CW linac based on rf superconductivity and making use of multiple recirculation. Its major components are a 50 MeV injector, two linac segments of 0.5 GeV energy gain each, and recirculator arcs connecting the two linac segments. Each linac segment consists of 25 cryomodules, separated by warm sections with quadrupoles, steering magnets, and beam diagnostics. Each cryomodule contains 8, 1500 MHz, 5-cell, Cornell type cavities with waveguide couplers for fundamental power and HOM damping, each cavity being powered by its own klystron. Recirculator arcs are vertically stacked, large radius, strong focusing beam lines that minimize synchrotron radiation effects. A high quality (ΔE/E ∼ 10 -4 , ε ∼ 10 -9 m) beam of 200μA, 100% duty factor, with 0.5 GeV ≤ E ≤ 4.0 GeV will be generated

  16. Environmental Management Assessment of the Continuous Electron Beam Accelerator Facility (CEBAF)

    International Nuclear Information System (INIS)

    1993-03-01

    This report documents the results of the Environmental Management Assessment performed at the Continuous Electron Beam Accelerator Facility (CEBAF) in Newport News, Virginia. During this assessment, activities and records were reviewed and interviews were conducted with personnel from the CEBAF Site Office; the CEBAF management and operating contractor (M ampersand O), Southeastern Universities Research Association, Inc. (SURA); the Oak Ridge Field Office (OR); and the responsible DOE Headquarters Program Office, the Office of Energy Research (ER). The onsite portion of the assessment was conducted from March 8 through March 19, 1993, by the US Department of Energy's (DOE's) Office of Environmental Audit (EH-24) located within the office of Environment, Safety and Health (EH). DOE 5482.1 B, ''Environment, Safety and Health Appraisal Program,'' and Secretary of Energy Notice (SEN)-6E-92, ''Departmental Organizational and Management Arrangements,'' establish the mission of EH-24 to provide comprehensive, independent oversight of Department-wide environmental programs on behalf of the Secretary of Energy. The ultimate goal of EH-24 is enhancement of environmental protection and minimization of risk to public health and the environment. EH-24 accomplishes its mission utilizing systematic and periodic evaluations of the Department's environmental programs within line organizations, and through use of supplemental activities which serve to strengthen self-assessment and oversight functions within program, field, and contractor organizations

  17. The CEBAF accelerator control system: migrating from a TACL to an EPICS based system

    International Nuclear Information System (INIS)

    Watson, W.A. III; Barker, David; Bickley, Matthew; Gupta, Pratik; Johnson, R.P.

    1994-01-01

    CEBAF is in the process of migrating its accelerator and experimental hall control systems to one based upon EPICS, a control system toolkit developed by a collaboration among several DOE laboratories in the US. The new system design interfaces existing CAMAC hardware via a CAMAC serial highway to VME-based I/O controllers running the EPICS software; future additions and upgrades will for the most part go directly into VME. The decision to use EPICS followed difficulties in scaling the CEBAF-developed TACL system to full machine operation. TACL and EPICS share many design concepts, facilitating the conversion of software from one toolkit to the other. In particular, each supports graphical entry of algorithms built up from modular code, graphical displays with a display editor, and a client-server architecture with name-based I/O. During the migration, TACL and EPICS will interoperate through a socket-based I/O gateway. As part of a collaboration with other laboratories, CEBAF will add relational database support for system management and high level applications support. Initial experience with EPICS is presented, along with a plan for the full migration which is expected to be finished next year. ((orig.))

  18. Correction of dispersion and the betatron functions in the CEBAF accelerator

    International Nuclear Information System (INIS)

    Lebedev, V.A.; Bickley, M.; Schaffner, S.; Zeijts, J. van; Krafft, G.A.; Watson, C.

    1996-01-01

    During the commissioning of the CEBAF accelerator, correction of dispersion and momentum compaction, and, to a lesser extent, transverse transfer matrices were essential for robust operation. With changing machine conditions, repeated correction was found necessary. To speed the diagnostic process the authors developed a method which allows one to rapidly track the machine optics. The method is based on measuring the propagation of 30 Hz modulated betatron oscillations downstream of a point of perturbation. Compared to the usual methods of dispersion or difference orbit measurement, synchronous detection of the beam displacement, as measured by beam position monitors, offers significantly improved speed and accuracy of the measurements. The beam optics of the accelerator was altered to decrease lattice sensitivity at critical points and to simplify control of the betatron function match. The calculation of the Courant-Snyder invariant from signals of each pair of nearby beam position monitors has allowed one to perform on-line measurement and correction of the lattice properties

  19. Optics of beam recirculation in the CEBAF [Continuous Electron Beam Accelerator Facility] cw linac

    International Nuclear Information System (INIS)

    Douglas, D.R.

    1986-01-01

    The use of recirculation in linear accelerator designs requires beam transport systems that will not degrade beam quality. We present a design for the transport lines to be used during recirculation in the CEBAF accelerator. These beam lines are designed to avoid beam degradation through synchrotron radiation excitation or betatron motion mismatch, are insensitive to errors commonly encountered during beam transport, and are optimized for electron beams with energies of 0.5 to 6.0 GeV. Optically, they are linearly isochronous second order achromats based on a ''missing magnet'' FODO structure. We give lattice specifications for, and results of analytic estimates and numerical simulations of the performance of, the beam transport system

  20. CEBAF cryomodules

    International Nuclear Information System (INIS)

    Campisi, I.E.; Ahlman, R.; Augustine, M.; Crawford, K.; Drury, M.; Jordan, K.; Kelley, P.; Lee, T.; Marshall, J.; Preble, J.; Robb, J.; Schneider, W.; Susta, J.; Van Dyke, J.; Wiseman, M.

    1991-01-01

    The Continuous Electron Beam Accelerator Facility, (CEBAF) is undergoing construction in Newport News, Virginia. When completed in 1994, the accelerator will be the largest installation of radio frequency superconductivity. Production of cryomodules, the fundamental cryogenic building block of the machine, has started. They consist of four sets of a pair of 1497 MHz, 5-cell cavities contained in separate helium vessels and mounted in a cryostat with appropriate end caps for helium supply and return. In this paper RF, heat load, and mechanical performance of the first unit tested and status of the project is discussed

  1. Experimental aspects of hypernuclear physics at CEBAF [Continuous Electron Beam Accelerator Facility

    International Nuclear Information System (INIS)

    Mecking, B.A.

    1987-01-01

    The general features of the electromagnetic excitation of hypernuclei are outlined. Experimental aspects of investigating these reactions at CEBAF are discussed. Two specific experimental set-ups are compared. 17 refs., 6 figs

  2. CEBAF design overview and project status

    International Nuclear Information System (INIS)

    Leemann, C.

    1988-01-01

    The Continuous Beam Accelerator Facility (CEBAF) will be an electron accelerator for nuclear physics research providing continuous beams with energies up to at least 4 GeV. The CEBAF is a recirculating linac. The design rationale, performance objectives, concept and fundamental choices for the CEBAF are discussed. 19 references, 10 figures, 1 table

  3. Workshop on CEBAF [Continuous Electron Beam Accelerator Facility] spectrometer magnet design and technology: Proceedings

    International Nuclear Information System (INIS)

    1986-09-01

    The planned experimental program at CEBAF includes high-resolution, large acceptance spectrometers and a large toroidal magnetic, detector. In order to take full advantage of the high quality beam characteristics, the performances required will make these devices quite unique instruments compared to existing facilities in the same energy range. Preliminary designs have shown that such performances can be reached, but key questions concerning design concepts and most appropriate and cost-effective technologies had to be answered before going further with the designs. It was the purpose of the Workshop on CEBAF Spectrometer Magnet Design and Technology, organized by the CEBAF Research and Engineering Divisions, to provide the most complete information about the state-of-the-art tools and techniques in magnet design and construction and to discuss the ones most appropriate to the CEBAF spectrometers. In addition, it is expected that this Workshop will be the staring point for further interactions and collaborations between international magnet experts and the CEBAF staff, during the whole process of designing and building the spectrometers

  4. Use of the TACL [Thaumaturgic Automated Control Logic] system at CEBAF [Continuous Electron Beam Accelerator Facility] for control of the Cryogenic Test Facility

    International Nuclear Information System (INIS)

    Navarro, E.; Keesee, M.; Bork, R.; Grubb, C.; Lahti, G.; Sage, J.

    1989-01-01

    A logic-based control software system, called Thaumaturgic Automated Control Logic (TACL), is under development at the Continuous Electron Beam Accelerator Facility in Newport News, VA. The first version of the software was placed in service in November, 1987 for control of cryogenics during the first superconducting RF cavity tests at CEBAF. In August, 1988 the control system was installed at the Cryogenic Test Facility (CTF) at CEBAF. CTF generated liquid helium in September, 1988 and is now in full operation for the current round of cavity tests. TACL is providing a powerful and flexible controls environment for the operation of CTF. 3 refs

  5. HUGS [Hampton University Graduate Studies] at CEBAF [Continuous Electron Beam Accelerator Facility

    International Nuclear Information System (INIS)

    1987-01-01

    This report discusses the following topics: hypernuclear physics with CEBAF emphasis; instructive aspects of few body systems; the three nucleon system: a review of lectures presented by Dr. J.L. Friar; special filter paper analyses and preliminary data derived therefrom; quarks and nuclear physics; perturbative QCD calculations of form factors; basic experimental instrumentation; electromagnetic interactions: the 'Super-Rosenbluth' decomposition; a longitudinal/transverse separation of the 12 C (e.e'p) reaction at quasielastic kinematics; and antiproton form factor from PQCD

  6. CEBAF cryogenic system

    International Nuclear Information System (INIS)

    Brindza, P.; Rode, C.

    1986-01-01

    The Continuous Electron Beam Accelerator Facility (CEBAF) is a standing wave superconducting linear accelerator with a maximum energy of 4 GeV and 200 μA beam current. The 418 Cornell/CEBAF superconducting niobium accelerating cavities are arranged in two 0.5 GeV linacs with magnetic recirculating arcs at each end. These accelerating cavities are arranged in pairs in a cryounit. The ensemble of four cryounits (8 cavities) together with their end caps makes up a complete cryostat called a cryogenic module. The four cryounit helium vessels are cross connected to each other and share a common cryogen supply, radiation shield and insulating vacuum. The cryogenics system for CEBAF consists of a 5kW central helium refrigerator and a transfer line system to supply 2.2 K 2.8 ATM helium to the cavity cryostats, 40 K helium at 3.5 ATM to the radiation shields and 4.5K helium at 2.8 ATM to the superconducting magnetic spectrometers in the experimental halls. Both the 2.2 K and the 4.5 K helium are expanded by Joule-Thompson (JT) valves in the individual cryostats yielding 2.0 K at .031 ATM and 4.4 K at 1.2 ATM respectively. The Central Helium Refrigerator is located in the center of the CEBAF racetrack with the transfer lines located in the linac tunnels

  7. CEBAF cryogenic system design

    International Nuclear Information System (INIS)

    Rode, C.; Brindza, P.

    1986-01-01

    The Continuous Electron Beam Accelerator Facility (CEBAF) is a standing wave superconducting linear accelerator with a maximum energy of 4 GeV and 200 μA beam current. The 418 Cornell/CEBAF superconducting niobium accelerating cavities are arranged in two 0.5 GeV linacs with magnetic recirculating arcs at each end. There is one recirculating arc for each energy beam that is circulating and any three of the four correlated energies may be supplied to any of the three experimental halls. The cryogenics system for CEBAF consists of a 5kW central helium refrigerator and a transfer line system to supply 2.2 K 2.8 ATM helium to the cavity cryostats, 40 K helium at 3.5 ATM to the radiation shields and 4.5K helium at 2.8 ATM to the superconducting magnetic spectrometers in the experimental halls. Both the 2.2K and the 4.5K helium are expanded by Joule-Thompson (JT) valves in the individual cryostats yielding 2.0K at .031 ATM and 4.4K at 1.2 ATM respectively. The Central Helium Refrigerator is located in the center of the CEBAF racetrack with the transfer lines located in the linac tunnels

  8. Dark currents for CEBAF linacs

    International Nuclear Information System (INIS)

    Yunn, B.C.

    1995-01-01

    Continuing on our numerical study of field emitted electrons from a superconducting CEBAF cavity we have identified all possible emission sites, magnitudes, and the energy profile of dark currents expected at CEBAF under nominal operating conditions. We find that most electrons do not survive beyond a single cryomodule which includes eight 5-cell superconducting cavities. However, some electrons can be accelerated through many cryomodules, ending up with an energy close to 100 MeV. However, no field emitted electrons can be recirculated along with an electron beam generated at the gun, due to the limited energy acceptance of CEBAF recirculation arcs. 4 refs., 4 figs

  9. The CEBAF Element Database and Related Operational Software

    Energy Technology Data Exchange (ETDEWEB)

    Larrieu, Theodore [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Slominski, Christopher [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Keesee, Marie [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Turner, Dennison [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Joyce, Michele [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    2015-09-01

    The newly commissioned 12GeV CEBAF accelerator relies on a flexible, scalable and comprehensive database to define the accelerator. This database delivers the configuration for CEBAF operational tools, including hardware checkout, the downloadable optics model, control screens, and much more. The presentation will describe the flexible design of the CEBAF Element Database (CED), its features and assorted use case examples.

  10. CEBAF [Continuous Electron Beam Accelerator Facility] design overview and project status

    International Nuclear Information System (INIS)

    Leemann, C.

    1988-01-01

    This paper discusses the design and specifications of the Continuous Electron Beam Accelerator Facility. Beam performance objectives are discussed, as well as the recirculating linac concept, the injector, cavities, cryogenic system, beam transport and optics, rf system and construction progress. 19 refs., 10 figs

  11. CEBAF/SURA [Continuous Electron Beam Accelerator Facility]/[Southeastern Universities Research Association] 1988 summer workshop

    International Nuclear Information System (INIS)

    Gross, F.; Lightbody, J.

    1989-01-01

    This report contains papers from a summer workshop of the continuous electron beam accelerator facility. Some topics of these papers are: spectrometers; electron scattering from deuterons; relativistic correlations in nuclear matter; pion production on 3 He and 3 H; quantum electrodynamic processes in crystals; 12 C(e,e'p) x reaction; deuteron polarization tensor and relativistic spin rotation; electromagnetic excitation of nuclei; electron distortion and structure functions in (e,e'p) reactions; and reaction mechanism of 4 He(e,e'p) 3 H

  12. CEBAF - environmental protection program plan

    International Nuclear Information System (INIS)

    1995-01-01

    An important objective in the successful operation of the Continuous Electron Beam Accelerator Facility (CEBAF) is to ensure protection of the public and the environment. To meet this objective, the Southeastern Universities Research Association, Inc., (SURA) is committed to working with the US Department of Energy (DOE) to develop, implement, and manage a sound and workable environmental protection program at CEBAF. This environmental protection plan includes information on environmental monitoring, long-range monitoring, groundwater protection, waste minimization, and pollution prevention awareness program plan

  13. Alignment of CEBAF cryomodules

    International Nuclear Information System (INIS)

    Schneider, W.J.; Bisognano, J.J.; Fischer, J.

    1993-06-01

    CEBAF, the Continuous Electron Beam Accelerator Facility, when completed, will house a 4 GeV recirculating accelerator. Each of the accelerator's two linacs contains 160 superconducting radio frequency (SRF) 1497 MHz niobium cavities in 20 cryomodules. Alignments of the cavities within the cryomodule with respect to beam axis is critical to achieving the optimum accelerator performance. This paper discusses the rationale for the current specification on cavity mechanical alignment: 2 mrad (rms) applied to the 0.5 m active length cavities. We describe the tooling that was developed to achieve the tolerance at the time of cavity pair assembly, to preserve and integrate alignment during cryomodule assembly, and to translate alignment to appropriate installation in the beam line

  14. HUGS at CEBAF [Hampton University Graduate Studies at the Continuous Electron Beam Accelerator Facility] June 6--24, 1988

    International Nuclear Information System (INIS)

    1988-01-01

    Topics discussed in this paper are: Physics thru the last 80 years; low energy neutron physics at LAMPF; experiments on P-violation; nucleon structure structure and nucleon resonances; electro-excitation of nucleon resonances; electron scattering (e,e'p) experiments; quasielastic scattering of electron with nucleus (introduction to (e,e'P) experiment); CEBAF's machine; quantum hadrodynamics-QHD-1 the Walecka model; relativistic nuclear dynamics; hybrid models and QCD; and modeling confinement: poor man's version

  15. Radiation control at the Continuous Electron Beam Accelerator Facility (CEBAF), a new high power CW electron accelerator installation

    International Nuclear Information System (INIS)

    Stapleton, G.B.; Thomas, R.H.

    1989-01-01

    A description is given of the design goals and radiation control measures, for a new 4 GeV, 1 MW electron accelerator under construction in the USA. The paper illustrates the importance of cooperation between designers and regulators. 15 refs., 1 fig., 3 tabs

  16. Operating experience at CEBAF

    International Nuclear Information System (INIS)

    Legg, R.

    1996-01-01

    CEBAF, the Continuous Electron Beam Accelerator Facility, is a 5-pass, recirculating, superconducting rf linac designed to provide exceptional beam quality at 4 GeV up to 200 μA CW. It is made up of an injector, two 400-MeV linacs, and 9 recirculation arcs having a total beamline length of more than 4.5 km. On Nov. 5, 1995, CEBAF delivered a 4 GeV, 25-μA CW electron beam to the first of 3 experimental halls and the experimental physics program was started 10 days later. Accelerator availability during the first month of the experimental run exceeded 75%. Beam properties measured in the experimental hall to date are a one sigma momentum spread of 5x10 -5 and an rms emittance of 0.2 nanometer-radians, better than design specification. CW beam has been provided from all 5 passes at 800 MeV intervals. Outstanding performance of the superconducting linacs suggests a machine energy upgrade to 6 GeV in the near term with eventual machine operation at 8-10 GeV. Results from commissioning and operations experience since the last conference are presented

  17. LEP and CEBAF polarimeters

    International Nuclear Information System (INIS)

    Placidi, M.; Burkert, V.; Rossmanith, R.

    1988-01-01

    This paper gives an overview on high energy electron (positron) polarimeters by describing in more detail the plans for the LEP polarimeter and the CEBAF polarimeters. Both LEP and CEBAF will have laser polarimeters. In addition CEBAF will be equipped with a Moller polarimeter (for currents below 1μA). 10 figs

  18. The CEBAF control system for the CHL

    International Nuclear Information System (INIS)

    Keesee, M.S.; Bevins, B.S.

    1996-01-01

    The CEBAF Central Helium Liquefier (CHL) control system consists of independent safety controls located at each subsystem, CAMAC computer interface hardware, and a CEBAF-designed control software called Thaumaturgic Automated Control Logic (TACL). The paper describes how control software was interfaced with the subsystems of the CHL. Topics of configuration, editing, operator interface, datalogging, and internal logic functions are presented as they relate to the operational needs of the helium plant. The paper also describes the effort underway to convert from TACL to the Experimental Physics and Industrial Control System (EPICS), the new control system for the CEBAF accelerator. This software change will require customizing EPICS software to cryogenic process control

  19. CEBAF Control Room Renovation

    International Nuclear Information System (INIS)

    Michael Spata; Thomas Oren

    2005-01-01

    The Machine Control Center (MCC) at Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) was initially constructed in the early 1990s and based on proven technology of that era. Through our experience over the last 15 years and in our planning for the facility's 12 GeV upgrade we reevaluated the control room environment to capitalize on emerging visualization and display technologies and improve workflow processes and ergonomic attributes. This effort also sets the foundation for the redevelopment of the accelerator's control system to deliver high reliability performance with improvements in beam specifications management and information flow. The complete renovation was performed over a three-week maintenance period with no interruption to beam operations. We present the results of this effort

  20. The CEBAF control system

    International Nuclear Information System (INIS)

    Watson, W.A. III.

    1995-01-01

    CEBAF has recently upgraded its accelerator control system to use EPICS, a control system toolkit being developed by a collaboration among laboratories in the US and Europe. The migration to EPICS has taken place during a year of intense commissioning activity, with new and old control systems operating concurrently. Existing CAMAC hardware was preserved by adding a CAMAC serial highway link to VME; newer hardware developments are now primarily in VME. Software is distributed among three tiers of computers: first, workstations and X terminals for operator interfaces and high level applications; second, VME single board computers for distributed access to hardware and for local control processing; third, embedded processors where needed for faster closed loop operation. This system has demonstrated the ability to scale EPICS to controlling thousands of devices, including hundreds of embedded processors, with control distributed among dozens of VME processors executing more than 125,000 EPICS database records. To deal with the large size of the control system, CEBAF has integrated an object oriented database, providing data management capabilities for both low level I/O and high level machine modeling. A new callable interface which is control system independent permits access to live EPICS data, data in other Unix processes, and data contained in the object oriented database

  1. CEBAF's SRF cavity manufacturing experience

    International Nuclear Information System (INIS)

    Benesch, J.F.; Reece, C.E.

    1994-01-01

    Construction of the Continuous Electron Beam Accelerator Facility (CEBAF) recirculating linac represents the largest scale application of superconducting rf (SRF) technology to date. The accelerating structures in CEBAF are 169 pairs of 1.5 GHz superconducting rf cavities -- 9 pairs in an injector and 80 pairs each in two linacs. The beam is to be recirculated up to five passes through each linac. Data is presented on mechanical tolerances achieved by the industrial fabricator of the rf cavities (Siemens). Liquid helium leak rates integrated over 22 vacuum seals have been measured on over 110 cavity pairs. A roughly normal distribution of the log 10 (leak rate) is seen, centered about a rate of 10 -10.4 torr-l/s. Over 140 pairs of the cavities have been assembled and have completed rf testing at 2.0 K. Among these, 54% demonstrated usable accelerating gradients greater than 10 MV/m. Although the rf performance characteristics well exceed the CEBAF baseline requirements of 5 MV/m at Q 0 = 2.4x10 9 , the usual limiting phenomena are encountered: field emission, quenching, and occasional multipacting. A discussion of the occurrence conditions and severity of these phenomena during production cavity testing is presented. The frequency with which performance is limited by quenching suggests that additional material advances may be required for applications which require the reliable achievement of accelerating gradients of more than 15 MV/m

  2. CEBAF Control Room Renovation

    International Nuclear Information System (INIS)

    Michael Spata; Anthony Cuffe; Thomas Oren

    2005-01-01

    The Machine Control Center (MCC) at Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) was constructed in the early 1990s and based on proven technology of that era. Through our experience over the last 15 years and in our planning for the facilities 12 GeV upgrade we reevaluated the control room environment to capitalize on emerging visualization and display technologies and improve on work-flow processes and ergonomic attributes. The renovation was performed in two phases during the summer of 2004, with one phase occurring during machine operations and the latter, more extensive phase, occurring during our semi-annual shutdown period. The new facility takes advantage of advances in display technology, analog and video signal management, server technology, ergonomic workspace design, lighting engineering, acoustic ceilings and raised flooring solutions to provide a marked improvement in the overall environment of machine operations

  3. RF superconductivity at CEBAF

    International Nuclear Information System (INIS)

    1990-01-01

    The Continuous Electron Beam Accelerator Facility (CEBAF) is a 4 GeV continuous beam electron accelerator being constructed to perform nuclear physics research. Construction began in February 1987 and initial operation is scheduled for February 1994. The present report describes its prototyping, problems/solutions, further development, facilities, design status, production and upgrade potential. The accelerator is 1.4 km in circumference, and has a race-track shape. It is of the recirculated linear accelerator type, and employs a total of five passes. Two linacs on opposite sides of the race-track each provide 400 MeV per pass. Beams of various energies are transported by separated arcs at each end of the straight sections to provide the recirculation. There are 4 recirculation arcs at the injector end, and 5 arcs at the other end. The full energy beam is routed by an RF separator to between one and three end stations, as desired, on a bucket-by-bucket basis. The average output beam current is 200 microamperes. Acceleration is provided by 338 superconducting cavities, which are arranged in pairs, each of which is enclosed in a helium vessel and suspended inside a vacuum jacket without ends. (N.K.)

  4. HUGS at CEBAF: Proceedings of the Hampton University Graduate Studies at the Continuous Electron Beam Accelerator Facility

    International Nuclear Information System (INIS)

    Buck, W.W.

    1989-01-01

    This report contains papers on the following topics: breaking and restoration of Chiral symmetry; an introduction to the QCD quark model and hadron spectroscopy; observations of ultra high energy emission from Cygnus X-3; parity violation program at CEBAF; testing the standard model via nuclear current interactions; collective models in excited nuclei and excited baryons; cold fusion; Δ electroproduction and inelastic charge scattering from carbon and iron; electron scattering and sum rules in nuclear physics; nuclear matter saturation in a U(1) circle-times Chiral model; effective action in path integral approach for a scalar field theory; many body approach to electron scattering; non-resonant N-N pion production; large N c expansion, from QCD to Skyrme; relativistic methods for few-body systems; and structure of excited nuclei and baryons (breaking of reflection symmetry)

  5. Free-electron lasers considered for CEBAF

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    Spinoff development of industrial free-electron lasers is in prospect for an industry-universitylaboratory consortium centred at the Continuous Electron Beam Accelerator Facility in Newport News, Virginia, site of the CEBAF 4 GeV superconducting radiofrequency (SRF) accelerator, now being commissioned (see page 42). Together with several US corporations and universities, the Laboratory is now also addressing the potential of smaller SRF electron accelerators for ''driving'' free-electron lasers (FELs)

  6. The CEBAF RF separator system

    International Nuclear Information System (INIS)

    Hovater, C.; Arnold, G.; Fugitt, J.; Harwood, L.; Kazimi, R.; Lahti, G.; Mammosser, J.; Nelson, R.; Piller, C.; Turlington, L.

    1996-01-01

    The 4 GeV CEBAF accelerator at Thomas Jefferson National Accelerator Facility (Jefferson Lab) is arranged in a five-pass racetrack configuration, with two superconducting radio-frequency (SRF) linacs joined by independent magnetic transport arcs. The 1497 MHz continuous electron beam is composed of three interlaced variable-intensity 499 MHz beams that can be independently directed from any of the five passes to any of the three experimental halls. Beam extraction is made possible by a system of nine warm sub-harmonic separator cavities capable of delivering a 100 urad kick to any pass at a maximum machine energy of 6 GeV. Each separator cavity is a half-wavelength, two cell design with a high transverse shunt impedance and a small transverse dimension. The cavities are powered by 1 kW solid state amplifiers operating at 499 MHz. Cavity phase and gradient control are provided through a modified version of the same control module used for the CEBAF SRF cavity controls. The system has recently been tested while delivering beam to Hall C. In this paper we present a description of the RF separator system and recent test results with beam. (author)

  7. BEAM EMITTANCE MEASUREMENT TOOL FOR CEBAF OPERATIONS

    International Nuclear Information System (INIS)

    Chevtsov, Pavel; Tiefenback, Michael

    2008-01-01

    A new software tool was created at Jefferson Lab to measure the emittance of the CEBAF electron beams. The tool consists of device control and data analysis applications. The device control application handles the work of wire scanners and writes their measurement results as well as the information about accelerator settings during these measurements into wire scanner data files. The data analysis application reads these files and calculates the beam emittance on the basis of a wire scanner data processing model. Both applications are computer platform independent but are mostly used on LINUX PCs recently installed in the accelerator control room. The new tool significantly simplifies beam emittance measurement procedures for accelerator operations and contributes to a very high availability of the CEBAF machine for the nuclear physics program at Jefferson Lab.

  8. CEBAF control system

    International Nuclear Information System (INIS)

    Bork, R.; Grubb, C.; Lahti, G.; Navarro, E.; Sage, J.

    1989-01-01

    A logic-based computer control system is in development at CEBAF. This Unix/C language software package, running on a distributed, hierarchical system of workstation and supervisory minicomputers, interfaces to hardware via CAMAC. Software aspects to be covered are ladder logic, interactive database generation, networking, and graphic user interfaces. 1 fig

  9. CEBAF Upgrade Bunch Length Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Mahmoud [Old Dominion Univ., Norfolk, VA (United States)

    2016-05-01

    Many accelerators use short electron bunches and measuring the bunch length is important for efficient operations. CEBAF needs a suitable bunch length because bunches that are too long will result in beam interruption to the halls due to excessive energy spread and beam loss. In this work, bunch length is measured by invasive and non-invasive techniques at different beam energies. Two new measurement techniques have been commissioned; a harmonic cavity showed good results compared to expectations from simulation, and a real time interferometer is commissioned and first checkouts were performed. Three other techniques were used for measurements and comparison purposes without modifying the old procedures. Two of them can be used when the beam is not compressed longitudinally while the other one, the synchrotron light monitor, can be used with compressed or uncompressed beam.

  10. Performance experience with the CEBAF SRF cavities

    International Nuclear Information System (INIS)

    Reece, C.; Benesch, J.; Drury, M.; Hovater, C.; Mammosser, J.; Preble, J.

    1995-01-01

    The full complement of 169 pairs of niobium superconducting cavities has been installed in the CEBAF accelerator. This paper surveys the performance characteristics of these cavities in vertical tests, commissioning in the tunnel, and operational experience to date. Although installed performance exceeds specifications, and 3.2 GeV beam has been delivered on target, present systems do not consistently preserve the high performance obtained in vertical dewar tests as operational capability. Principal sources of these limitations are discussed

  11. CEBAF cryogenic system

    International Nuclear Information System (INIS)

    1995-01-01

    The CEBAF cryogenic system consists of 3 refrigeration systems: Cryogenic Test Facility (CTF), Central Helium Liquefier (CHL), and End Station Refrigerator (ESR). CHL is the main cryogenic system for CEBAF, consisting of a 4.8 kW, 2.0 K refrigerator and transfer line system to supply 2.0 K and 12 kW of 50 K shield refrigeration for the Linac cavity cryostats and 10 g/s of liquid for the end stations. This paper describes the 9-year effort to commission these systems, concentrating on CHL with the cold compressors. The cold compressors are a cold vacuum pump with an inlet temperature of 3 K which use magnetic bearings, thereby eliminating the possibility of air leaks into the subatmospheric He

  12. Commissioning of the 123 MeV injector for 12 GeV CEBAF

    International Nuclear Information System (INIS)

    Wang, Yan; Hofler, Alicia S.; Kazimi, Reza

    2015-09-01

    The upgrade of CEBAF to 12GeV included modifications to the injector portion of the accelerator. These changes included the doubling of the injection energy and relocation of the final transport elements to accommodate changes in the CEBAF recirculation arcs. This paper will describe the design changes and the modelling of the new 12GeV CEBAF injector. Stray magnetic fields have been a known issue for the 6 GeV CEBAF injector, the results of modelling the new 12GeV injector and the resulting changes implemented to mitigate this issue are described in this paper. The results of beam commissioning of the injector are also presented.

  13. Therminoic gun control system for the CEBAF injector

    International Nuclear Information System (INIS)

    Pico, R.; Diamond, B.; Fugitt, J.; Bork, R.

    1989-01-01

    The injector for the CEBAF accelerator must produce a high-quality electron beam to meet the overall accelerator specifications. A Hermosa electron gun with a 2 mm-diameter cathode and a control aperture has been chosen as the electron source. This must be controlled over a wide range of operating conditions to meet the beam specifications and to provide flexibility for accelerator commissioning. The gun is controlled using Computer Automated Measurement and Control (CAMAC IEEE-583) technology. The system employs the CAMAC-based control architecture developed at CEBAF. The control system has been tested, and early operating data on the electron gun and the injector beam transport system has been obtained. This system also allows gun parameters to be stored at the operator location, without paralyzing operation. This paper describes the use of this computer system in the control of the CEBAF electron gun. 2 refs., 6 figs., 1 tab

  14. Commissioning of the CEBAF cryomodules

    International Nuclear Information System (INIS)

    Drury, M.; Lee, T.; Marshall, J.; Preble, J.; Saulter, Q.; Schneider, W.; Spata, M.; Wiseman, M.

    1993-01-01

    When complete, the Continuous Electron Beam Accelerator Facility will house a 4 GeV recirculating linear accelerator containing 42 1/4 cryomodules arrayed in two antiparallel linacs and an injector. Currently, over half of the cryomodules have been installed. Each cryomodule contains eight superconducting niobium 5-cell rf cavities that operate at 1.497 GHz. A cryomodule must provide an energy gain of 20 MeV to the 200 μA beam. The resultant dynamic heat load must be less than 45 W. The cavity parameters that are measured during the commissioning process include the external Q's of the cavity ports, the unloaded Q (Q 0 ) of the cavity as a function of accelerating gradient, and the maximum operating gradient of the cavity. The sensitivity of the resonant frequency to changes in pressure and gradient is also measured. Finally, the mechanical tuners are cycled and characterized. In all cases, the performance of CEBAF cryomodules has exceeded the design requirements. A portable test stand allows local control of the rf system and provides automated data acquisition. This paper describes the cryomodule commissioning hardware, software, and measurements

  15. Conceptual design report, CEBAF basic experimental equipment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1990-04-13

    The Continuous Electron Beam Accelerator Facility (CEBAF) will be dedicated to basic research in Nuclear Physics using electrons and photons as projectiles. The accelerator configuration allows three nearly continuous beams to be delivered simultaneously in three experimental halls, which will be equipped with complementary sets of instruments: Hall A--two high resolution magnetic spectrometers; Hall B--a large acceptance magnetic spectrometer; Hall C--a high-momentum, moderate resolution, magnetic spectrometer and a variety of more dedicated instruments. This report contains a short description of the initial complement of experimental equipment to be installed in each of the three halls.

  16. Operational experience with the CEBAF control system

    International Nuclear Information System (INIS)

    Hovater, C.; Chowdhary, M.; Karn, J.; Tiefenback, M.; Zeijts, J. van; Watson, W.

    1996-01-01

    The CEBAF accelerator at Thomas Jefferson National Accelerator Facility (Jefferson Lab) successfully began its experimental nuclear physics program in November of 1995 and has since surpassed predicted machine availability. Part of this success can be attributed to using the EPICS (Experimental Physics and Industrial Control System) control system toolkit. The CEBAF control system is one of the largest accelerator control system now operating. It controls approximately 338 SRF cavities, 2,300 magnets, 500 beam position monitors and other accelerator devices, such as gun hardware and other beam monitoring devices. All told, the system must be able to access over 125,000 database records. The system has been well received by both operators and the hardware designers. The EPICS utilities have made the task of troubleshooting systems easier. The graphical and test-based creation tools have allowed operators to custom build control screens. In addition, the ability to integrate EPICS with other software packages, such as Tcl/Tk, has allowed physicists to quickly prototype high-level application programs, and to provide GUI front ends for command line driven tools. Specific examples of the control system applications are presented in the areas of energy and orbit control, cavity tuning and accelerator tune up diagnostics

  17. Beam transport magnets for CEBAF

    International Nuclear Information System (INIS)

    Harwood, L.H.; Biallas, G.; Boyce, J.R.; Heilbrunn, W.; Johnson, K.; York, R.C.

    1989-01-01

    With respect to the optical system, the challenging parameters of the Continuous Electron Beam Accelerator Facility (CEBAF), a five pass recirculating electron linac, are the design goals for the emittance and energy spread of its beam. The design goals are an emittance of 2 /times/ 10/sup /minus/9/ m-rad at E 0 ≤ 0.8 kG), 390 major dipoles (/ell/ = 1, 2, and 3 m; 2 ≤ B 0 ≤ 6 kG); 707 quadrupoles (0.15, 0.30, 0.6 m; B 0 ≤ 4 kG), 96 sextupoles (/ell/ = 0.3 m, B 0 ≤ 0.2 kG), 26 septa (/ell/ = 1, 2 m; 0.3 ≤ B 0 ≤ 6 kG), and one lambertson septum (/ell/ = 1 m; B 0 ≅ 4 kG), for a total of 2267 individual magnets. Furthermore, the fact that the quadrupoles, sextupoles, and correctors are to be individually powered to provide flexibility in tuning the optics lattice leads to restrictions on their design parameters. To ensure that the required magnetic parameters are achieved, all magnets will be magnetically mapped before installation. Therefore, systems to accurately and rapidly measure the multipoles and major dipoles are required. In this paper, present planning and the results of tests performed on the system to date are outlined. 5 refs., 4 figs

  18. New window design options for CEBAF energy upgrade

    International Nuclear Information System (INIS)

    Phillips, L.; Mammosser, J.; Nguyen, V.

    1997-01-01

    As the Jefferson Laboratory upgrades the existing CEBAF electron accelerator to operate at higher energies, the fundamental power coupler windows will be required to operate with lower RF dissipation and increased immunity to radiation from cavity field emission. New designs and modifications to existing designs which can achieve these goals are described

  19. CEBAF at higher energies and the kaon electromagnetic form factor

    Energy Technology Data Exchange (ETDEWEB)

    Baker, O.K.

    1994-04-01

    The electromagnetic production of strangeness, the physics of exciting systems having strangeness degrees of freedom (production of hadrons with one or more strange constituent quarks) using electromagnetic probes (real or virtual photons), is one of the frontier areas of research which will be investigated at the Continuous Electron Beam Accelerator Facility (CEBAF) when it becomes operational. CEBAF is expected to have an important impact upon this field of research using its specialized set of detection instruments and high quality electron beam. This paper focusses upon one aspect of the associated production of strangeness - the determination of the kaon electromagnetic form factor at high squared momentum transfers.

  20. The CEBAF RF Separator System Upgrade

    International Nuclear Information System (INIS)

    Hovater, J.; Mark Augustine; Al Guerra; Richard Nelson; Robert Terrell; Mark Wissmann

    2004-01-01

    The CEBAF accelerator uses RF deflecting cavities operating at the third sub-harmonic (499 MHz) of the accelerating frequency (1497 MHz) to ''kick'' the electron beam to the experimental halls. The cavities operate in a TEM dipole mode incorporating mode enhancing rods to increase the cavity's transverse shunt impedance [1]. As the accelerators energy has increased from 4 GeV to 6 GeV the RF system, specifically the 1 kW solid-state amplifiers, have become problematic, operating in saturation because of the increased beam energy demands. Two years ago we began a study to look into replacement for the RF amplifiers and decided to use a commercial broadcast Inductive Output Tube (IOT) capable of 30 kW. The new RF system uses one IOT amplifier on multiple cavities as opposed to one amplifier per cavity as was originally used. In addition, the new RF system supports a proposed 12 GeV energy upgrade to CEBAF. We are currently halfway through the upgrade with three IOTs in operation and the remaining one nearly installed. This paper reports on the new RF system and the IOT performance

  1. Measuring and Controlling the Energy Spread in CEBAF

    CERN Document Server

    Krafft, G A; Dickson, R W; Kazimi, R; Lebedev, V A; Tiefenback, M G

    2000-01-01

    As compared to electron storage rings, one advantage of recirculating linear accelerators is that the beam properties at target are no longer dominated by the equilibrium between quantum radiative diffusion and radiation damping because new beam is continually injected into the accelerator. This allows the energy spread from a CEBAF-type machine to be relatively small; the measured energy spread from CEBAF at 4 GeV is less than 100 parts per million accumulated over times of order several days. In this paper, the various subsystems contributing to the energy spread of a CEBAF-type accelerator are reviewed, as well as the machine diagnostics and controls that are used in CEBAF to ensure that a small energy spread is provided during routine running. Examples of relevant developments are (1) stable short bunches emerging from the injector, (2) precision timing and phasing of the linacs with respect to the centroid of the beam bunches on all passes, (3) implementing 2 kHz sampling rate feedback systems for final ...

  2. Root Causes of Field Emitters in SRF Cavities Placed in CEBAF Tunnel

    Energy Technology Data Exchange (ETDEWEB)

    Geng, Rongli

    2016-05-01

    It has been suspected that appearance of new field emitters can occur in SRF cavities after their placement in accelerator tunnel for long term beam operation. This apparently has been the case for CEBAF. However, no physical evidence has been shown in the past. In this contribution, we will report on the recent results concerning the root cause of field emitters in SRF cavities placed in CEBAF tunnel. We will discuss these results in the context of high-reliability and low-cryogenic-loss operation of CEBAF.

  3. CEBAF beam viewer imaging software

    International Nuclear Information System (INIS)

    Bowling, B.A.; McDowell, C.

    1993-01-01

    This paper discusses the various software used in the analysis of beam viewer images at CEBAF. This software, developed at CEBAF, includes a three-dimensional viewscreen calibration code which takes into account such factors as multiple camera/viewscreen rotations and perspective imaging, and maintaining a calibration database for each unit. Additional software allows single-button beam spot detection, with determination of beam location, width, and quality, in less than three seconds. Software has also been implemented to assist in the determination of proper chopper RF control parameters from digitized chopper circles, providing excellent results

  4. Operational experience with synchrotron light interferometers for CEBAF experimental beam lines

    Energy Technology Data Exchange (ETDEWEB)

    Pavel Chevtsov

    2006-10-24

    Beam size and energy spread monitoring systems based on Synchrotron Light Interferometers (SLI) have been in operations at Jefferson Lab for several years. A non-invasive nature and a very high (a few mm) resolution of SLI make these instruments valuable beam diagnostic tools for the CEBAF accelerator. This presentation describes the evolution of the Synchrotron Light Interferometer at Jefferson Lab and highlights our extensive experience in the installation and operation of the SLI for CEBAF experimental beam lines.

  5. The founding of CEBAF, 1979 to 1987

    International Nuclear Information System (INIS)

    Westfall, C.

    1995-01-01

    -nuclear physics had attracted a considerable following. The growing electro-nuclear physics community was eager to find a scheme to permit virtually continuous acceleration, which would greatly improve the capability of performing coincidence experiments. In the words of the UVa conference proceedings, this experimental capability promised to open entire new areas of nuclear physics. Convinced that he could be the one to design the necessary groundbreaking machine after hearing the ideas of Loew and Servranckx, McCarthy began gathering a small accelerator building team. Against all odds, McCarthy's pipe dream resulted in the construction of a major accelerator laboratory, the Continuous Electron Beam Accelerator Facility (CEBAF). The founding of CEBAF is a tale of luck, perseverance, the triumph of flexible amateurism over rigid professionalism, and ironically, the potential of amateurs when supported by a thoroughly professional international network with well-defined methods for organizing and building accelerators. The CEBAF tale also has a surprise ending, for at the last minute, McCarthy's pipe dream was radically transformed by Hermann Grunder, who would direct the construction of the project. The twists and turns of this tale reveal many lessons about what aids and what detracts from the success of a large, federally sponsored scientific project

  6. CEBAF SRF Performance during Initial 12 GeV Commissioning

    International Nuclear Information System (INIS)

    Bachimanchi, Ramakrishna; Allison, Trent; Daly, Edward; Drury, Michael; Hovater, J; Lahti, George; Mounts, Clyde; Nelson, Richard; Plawski, Tomasz

    2015-09-01

    The Continuous Electron Beam Accelerator Facility (CEBAF) energy upgrade from 6 GeV to 12 GeV includes the installation of eleven new 100 MV cryomodules (88 cavities). The superconducting RF cavities are designed to operate CW at an accelerating gradient of 19.3 MV/m with a Q L of 3x10 7 . Not all the cavities were operated at the minimum gradient of 19.3 MV/m with the beam. Though the initial 12 GeV milestones were achieved during the initial commissioning of CEBAF, there are still some issues to be addressed for long term reliable operation of these modules. This paper reports the operational experiences during the initial commissioning and the path forward to improve the performance of C100 (100 MV) modules.

  7. CEBAF Control Room Renovation

    International Nuclear Information System (INIS)

    Michael Spata; Thomas Oren

    2005-01-01

    The Machine Control Center at Jefferson Lab's Continuous Electron Beam Accelerator Facility was initially constructed in the early 1990s and based on proven technology of that era. Through our experience over the last 15 years and in our planning for the facilities 12 GeV upgrade we reevaluated the control room environment to capitalize on emerging visualization and display technologies and improve on workflow processes and ergonomic attributes. This effort also sets the foundation for the redevelopment of the accelerator's control system to deliver high reliability performance with improvements in beam specifications management and information flow. The complete renovation was performed over a three-week period with no interruption to beam operations. We present the results of this effort

  8. Workshop on CEBAF at higher energies

    Energy Technology Data Exchange (ETDEWEB)

    Isgur, N.; Stoler, P. [eds.

    1994-04-01

    Since the current parameters of CEBAF were defined almost a decade ago, there has been a remarkably fruitful evolution of our picture of the behavior of strongly interacting matter that apparently could be addressed by CEBAF at higher energies. Favorable technical developments coupled with foresight in initial laboratory planning have now made it feasible to consider approximately doubling CEBAF`s current design energy of 4 GeV to approach 10 GeV at rather modest cost. The purpose of the workshop, sponsored by the CEBAF User Group, was to begin to develop the next phase of CEBAF`s program by giving the entire community the opportunity to participate in defining the future of our field, and in particular the physics accessible with an upgraded CEBAF energy. It is intended that this report mark the first step toward an ultimate goal of defining a physics program that will form the basis for an upgrade of CEBAF. The report begins with a brief overview of the workshop`s conclusions. Its body consists of sections corresponding to the workshop`s Working Groups on Hadron Spectroscopy and Production, High Q{sup 2} Form Factors and Exclusive Reactions, Inclusive and Semi-Inclusive Processes, and Hadrons in the Nuclear Medium. Each section begins with the working group summaries and is followed by associated plenary talks summarizing the outstanding physics issues addressable by an upgrade, which are in turn followed by individual contributions presenting specific physics programs. An appendix describes capabilities of CEBAF`s current experimental equipment at higher energies; another appendix lists workshop participants. Selected papers have been processed separately for inclusion in the Energy Science and Technology Database.

  9. CEBAF Cryomodule Commissioning in the South Linac

    International Nuclear Information System (INIS)

    M. Drury; H. Lankford; T. Lee; J. Marshall; J. Preble; Q. Saulter; W. Schneider; Michael Spata; Mark Wiseman

    1993-01-01

    When complete, the Continuous Electron Beam Accelerator Facility will house a 4 GeV recirculating linear accelerator containing 42 1/4 cryomodules arrayed in two antiparallel linacs and an injector. Currently, 38 1/4 cryomodules have been installed. Each cryomodule contains eight superconducting niobium 5-cell rf cavities that operate at 1.497 GHz[1]. A cryomodule must provide an energy gain of 20 MeV to the 200 mu-A beam[2]. The resultant dynamic heat load must be less than 45 W. The cavity parameters that are measured during the commissioning process include the external Q's (Q(sub ext)) of the cavity ports, the unloaded Q (Q(sub 0)) of the cavity as a function of accelerating gradient, and the maximum operating gradient of the cavity[3]. Finally, the mechanical tuners are cycled and characterized. A portable test stand allows local control of the rf system and provides automated data acquisition. During the period from April 1993 through September 1993, 16 of the 20 cryomodules installed in the South Linac were commissioned. All cryomodules tested in the South Linac meet or exceed the CEBAF specifications. This paper describes the results of the commissioning of the first 10 cryomodules in the South Linac

  10. Operation of CEBAF with heavy beamloading

    International Nuclear Information System (INIS)

    Hutton, A.

    1997-01-01

    CEBAF is a 4 GeV, 200 microA five-pass recirculating superconducting electron accelerator that has been operating for nuclear physics research at full energy since November 95. The beam current has been increased to over 180 microA at 4 GeV with the maximum current in the linac over 900 microA. The superconducting cavities operate in a regime where the beam-induced voltage is comparable to the accelerating gradient. The operational limits and the issues required to maintain stable operation of the 1,497 MHz superconducting cavities will be discussed, together with the implications for the other accelerator systems. There are three experimental Halls which can run simultaneously with three interleaved 499 MHz bunch trains and RF separators. Operation with simultaneous beams to two Halls is now routine, and simultaneous three beam operation has been demonstrated. The maximum design current per bunch train (120 microA) has been achieved. Hall B eventually requires beam currents as low as 1 nA (200 pA has been delivered) simultaneous with delivery of up to 200 microA to the other Halls. The required beam current ratio of 10,000 has been achieved; development of 1 nA beam position monitors continues

  11. A Tau-Charm Factory at CEBAF

    Energy Technology Data Exchange (ETDEWEB)

    Seth, K.K. [Northwestern Univ., Evanston, IL (United States)

    1994-04-01

    It is proposed that a Tau Charm Factory represents a natural extension of CEBAF into higher energy domains. The exciting nature of the physics of charm quarks and tau leptons is briefly reviewed and it is suggested that the concept of a linac-ring collider as a Tau Charm Factory at CEBAF should be seriously studied.

  12. HOM Survey of the First CEBAF Upgrade Style Cavity Pair

    International Nuclear Information System (INIS)

    Marhauser, Frank; Daly, Edward; Davis, G.; Drury, Michael; Grenoble, Christiana; Hogan, John; Manus, Robert; Preble, Joseph; Reece, Charles; Rimmer, Robert; Tian, Kai; Wang, Haipeng

    2009-01-01

    The planned upgrade of the Continuous Electron Beam Accelerator Facility (CEBAF) at the Thomas Jefferson National Accelerator Laboratory (JLab) requires ten new superconducting rf (SRF) cavity cryomodules to double the beam energy to the envisaged 12 GeV. Adequate cavity Higher Order Mode (HOM) suppression is essential to avoid multipass, multibunch beam break-up (BBU) instabilities of the recirculating beam. We report on detailed HOM surveys performed for the first two upgrade style cavities tested in a dedicated cavity pair cryomodule at 2K. The safety margin to the BBU threshold budget at 12 GeV has been assessed.

  13. Beam raster system at CEBAF

    International Nuclear Information System (INIS)

    Yan, C.; Beaufait, J.; Brindza, P.; Carlini, R.; Vulcan, W.; Wines, R.

    1993-01-01

    A cascade raster system will be used in Hall C at CEBAF to generate a variable rastering pattern on the polarized target, the cryogenic hydrogen target, and the beam dump with adjustable frequency up to 10 kHz and variable deflection angle from 0.05 mr to 1 mr. Each raster consists of two air-core bedstead coils providing transverse and vertical scans. The magnets are energized by individual MOS power amplifiers controlled by a scan generator which determines frequency, amplitude, and phase shift between the cascade rasters

  14. Numerical modelling of the CEBAF electron gun with EGUN

    International Nuclear Information System (INIS)

    Liger, P.; Krafft, G.A.

    1991-01-01

    The electron source used in the injector for the CEBAF accelerator is a Hermosa electron gun with a 2 mm diameter cathode and a control electrode. It produces a 100 keV electron beam to be focused on the first of two apertures which comprise an emittance filter. A normalized emittance of less than π mm mrad at 1.2 mA is set by the requirements of the final beam from the CEBAF linac, since downstream of the filter, a system of two choppers and a third aperture removes 5/6 of the current. In addition, for RF test purposes a higher current of about 5 mA is needed, possibly at higher emittance. This paper presents a way of calculating the characteristics of the CEBAF electron gun with the gun design code EGUN, and the accuracy of the results is discussed. The transverse shape of the beam delivered by the gun has been observed, and its current measured. A halo around the beam has been seen, and the calculations can reproduce this effect

  15. Cryogenics in CEBAF HMS dipole

    International Nuclear Information System (INIS)

    Bogensberger, P.; Ramsauer, F.; Brindza, P.; Wines, R.; Koefler, H.

    1994-01-01

    The paper will report upon the final design, manufacturing and tests of CEBAF's HMS Dipole cryogenic equipment. The liquid nitrogen circuits, the helium circuits and thermal insulation of the magnet will be addressed. The cryogenic reservoir and control module as an integral part of the HMS Dipole magnet will be presented. The construction, manufacturing, tests and final performance of the HMS Dipole cryogenic system will be reported. The LN 2 circuit and the He circuit are tied together by the control system for cool down, normal operation and standby. This system monitors proper temperature differences between both circuits and controls the cryogenic supply to meet the constraints. Implementation of the control features for the cryogenic system into the control system will be reported

  16. The CEBAF large acceptance spectrometer (CLAS)

    Energy Technology Data Exchange (ETDEWEB)

    Mecking, B.A.; Adams, G.; Ahmad, S.; Anciant, E.; Anghinolfi, M.; Asavapibhop, B.; Asryan, G.; Audit, G.; Auger, T.; Avakian, H.; Ball, J.P.; Barbosa, F.J.; Barrow, S.; Battaglieri, M.; Beard, K.; Berman, B.L.; Bianchi, N.; Boiarinov, S.; Bonneau, P.; Briscoe, W.J.; Brooks, W.K.; Burkert, V.D.; Carman, D.S.; Carstens, T.; Cetina, C.; Christo, S.B.; Cole, P.L.; Coleman, A.; Connelly, J.; Cords, D.; Corvisiero, P.; Crabb, D.; Crannell, H.; Cuevas, R.C.; Degtyarenko, P.V.; Dennis, L.; DeSanctis, E.; DeVita, R.; Distelbrink, J.; Dodge, G.E.; Dodge, W.; Doolittle, G.; Doughty, D.; Dugger, M.; Duncan, W.S.; Dytman, S.; Egiyan, H.; Egiyan, K.S.; Elouadrhiri, L.; Feuerbach, R.J.; Ficenec, J.; Frolov, V.; Funsten, H.; Gilfoyle, G.P.; Giovanetti, K.L.; Golovatch, E.; Gram, J.; Guidal, M.; Gyurjyan, V.; Heddle, D.; Hemler, P.; Hersman, F.W.; Hicks, K.; Hicks, R.S.; Holtrop, M.; Hyde-Wright, C.E.; Insley, D.; Ito, M.M.; Jacobs, G.; Jenkins, D.; Joo, K.; Joyce, D.; Kashy, D.; Khandaker, M.; Kim, W.; Klein, A.; Klein, F.J.; Klusman, M.; Kossov, M.; Kramer, L.; Koubarovski, V.; Kuhn, S.E.; Lake, A.; Lawrence, D.; Longhi, A.; Lukashin, K.; Lachniet, J.; Magahiz, R.A.; Major, W.; Manak, J.J.; Marchand, C.; Martin, C.; Matthews, S.K.; McMullen, M.; McNabb, J.W.C.; Mestayer, M.D.; Minehart, R.; Mirazita, M.; Miskimen, R.; Muccifora, V.; Mueller, J.; Murphy, L.Y.; Mutchler, G.S.; Napolitano, J.; Niculescu, I.; Niczyporuk, B.B.; Nozar, M.; O' Brien, J.T.; Opper, A.K.; O' Meara, J.E.; Pasyuk, E.; Philips, S.A.; Polli, E.; Price, J.W.; Pozdniakov, S.; Qin, L.M.; Raue, B.A.; Riccardi, G.; Ricco, G.; Riggs, C.; Ripani, M.; Ritchie, B.G.; Robb, J.; Ronchetti, F.; Rossi, P.; Roudot, F.; Salgado, C.; Sapunenko, V.; Schumacher, R.A.; Serov, V.S.; Sharabian, Y.G.; Smith, E.E.S. E-mail: elton@jlab.org; Smith, L.C.; Smith, T.; Sober, D.I.; Stavinsky, A.; Stepanyan, S.; Stoler, P.; Taiuti, M.; Taylor, W.M.; Taylor, S.; Tedeschi, D.J.; Thoma, U.; Thompson, R.; Tilles, D.; Todor, L. [and others

    2003-05-11

    The CEBAF large acceptance spectrometer (CLAS) is used to study photo- and electro-induced nuclear and hadronic reactions by providing efficient detection of neutral and charged particles over a good fraction of the full solid angle. A collaboration of about 30 institutions has designed, assembled, and commissioned CLAS in Hall B at the Thomas Jefferson National Accelerator Facility. The CLAS detector is based on a novel six-coil toroidal magnet which provides a largely azimuthal field distribution. Trajectory reconstruction using drift chambers results in a momentum resolution of 0.5% at forward angles. Cherenkov counters, time-of-flight scintillators, and electromagnetic calorimeters provide good particle identification. Fast triggering and high data-acquisition rates allow operation at a luminosity of 10{sup 34} nucleon cm{sup -2} s{sup -1}. These capabilities are being used in a broad experimental program to study the structure and interactions of mesons, nucleons, and nuclei using polarized and unpolarized electron and photon beams and targets. This paper is a comprehensive and general description of the design, construction and performance of CLAS.

  17. CEBAF NEW DIGITAL LLRF SYSTEM EXTENDED FUNCTIONALITY

    International Nuclear Information System (INIS)

    T. Allison; K. Davis; H. Dong; C. Hovater; L. King; J. Musson; T. Plawski

    2007-01-01

    The new digital LLRF system for the CEBAF 12GeV accelerator will perform a variety of tasks, beyond field control [1]. In this paper we present the superconducting cavity resonance control system designed to minimize RF power during gradient ramp and to minimize RF power during steady state operation. Based on the calculated detuning angle, which represents the difference between reference and cavity resonance frequency, the cavity length will be adjusted with a mechanical tuner. The tuner has two mechanical driving devices, a stepper motor and a piezo-tuner, to yield a combination of coarse and fine control. Although LLRF piezo processing speed can achieve 10 kHz bandwidth, only 10 Hz speed is needed for 12 GeV upgrade. There will be a number of additional functions within the LLRF system; heater controls to maintain cryomodule's heat load balance, ceramic window temperature monitoring, waveguide vacuum interlocks, ARC detector interlock and quench detection. The additional functions will be divided between the digital board, incorporating an Altera FPGA and an embedded EPICS IOC. This paper will also address hardware evolution and test results performed with different SC cavities

  18. CEBAF at higher energies: Working group report on hadron spectroscopy and production

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, T. [Oak Ridge National Laboratory, TN (United States)]| [Univ. of Tennessee, Knoxville (United States); Napolitano, J. [Rensselaer Polytechnic Inst., Troy, NY (United States)

    1994-04-01

    This report summarizes topics in hadron spectroscopy and production which could be addressed at CEBAF with an energy upgrade to E{sub {gamma}} = 8 GeV and beyond. The topics discussed include conventional meson and baryon spectrocopy, spectroscopy of exotica (especially molecules and hybrids), CP and CPT tests using {phi} mesons, and new detector and accelerator options.

  19. Workshop on CEBAF at higher energies

    International Nuclear Information System (INIS)

    Isgur, N.; Stoler, P.

    1994-04-01

    Since the current parameters of CEBAF were defined almost a decade ago, there has been a remarkably fruitful evolution of our picture of the behavior of strongly interacting matter that apparently could be addressed by CEBAF at higher energies. Favorable technical developments coupled with foresight in initial laboratory planning have now made it feasible to consider approximately doubling CEBAF's current design energy of 4 GeV to approach 10 GeV at rather modest cost. The purpose of the workshop, sponsored by the CEBAF User Group, was to begin to develop the next phase of CEBAF's program by giving the entire community the opportunity to participate in defining the future of our field, and in particular the physics accessible with an upgraded CEBAF energy. It is intended that this report mark the first step toward an ultimate goal of defining a physics program that will form the basis for an upgrade of CEBAF. The report begins with a brief overview of the workshop's conclusions. Its body consists of sections corresponding to the workshop's Working Groups on Hadron Spectroscopy and Production, High Q 2 Form Factors and Exclusive Reactions, Inclusive and Semi-Inclusive Processes, and Hadrons in the Nuclear Medium. Each section begins with the working group summaries and is followed by associated plenary talks summarizing the outstanding physics issues addressable by an upgrade, which are in turn followed by individual contributions presenting specific physics programs. An appendix describes capabilities of CEBAF's current experimental equipment at higher energies; another appendix lists workshop participants. Selected papers have been processed separately for inclusion in the Energy Science and Technology Database

  20. Modification of the CEBAF transport dipoles for energy upgrade considerations

    International Nuclear Information System (INIS)

    D. Bullard; L. Harwood; T. Hiatt; J. Karn; E. Martin; W. Oren; C. Rode; K. Sullivan; R. Wines; M. Wiseman

    1999-01-01

    The CEBAF accelerator at the Thomas Jefferson National Accelerator Facility contains 415 resistive dipoles in the recirculation arcs and transport lines. These dipoles were originally designed and magnetically mapped to support the operation of the accelerator at 6 GeV. Recent interests in upgrading the CEBAF energy beyond 6 GeV prompted a study into operating the dipoles beyond their design limits. Finite element modeling was performed to quantify saturation effects at higher currents and to test simple modifications to improve magnetic performance. For confirmation, various steps were prototyped and magnetically measured. Measurement results agreed with finite element models and showed that saturation could be reduced to manageable levels. It was found that the most populous dipole families could be modified to reach twice their design field with minimal cost and effort. At these higher fields, the magnets operate at a reasonable thermal state with minimal saturation losses a nd little degradation in field quality. Work continues on studying the smaller population of dipoles to determine their performance at higher fields

  1. A New RF System for the CEBAF Normal Conducting Cavities

    International Nuclear Information System (INIS)

    Curt Hovater; Hai Dong; Alicia Hofler; George Lahti; John Musson; Tomasz Plawski

    2004-01-01

    The CEBAF Accelerator at Jefferson Lab is a 6 GeV five pass electron accelerator consisting of two superconducting linacs joined by independent magnetic transport arcs. CEBAF also has numerous normal conducting cavities for beam conditioning in the injector and for RF extraction to the experimental halls. The RF systems that presently control these cavities are becoming expensive to maintain, therefore a replacement RF control system is now being developed. For the new RF system, cavity field control is maintained digitally using an FPGA which contains the feedback algorithm. The system incorporates digital down conversion, using quadrature under-sampling at an IF frequency of 70 MHz. The VXI bus-crate was chosen as the operating platform because of its excellent RFI/EMI properties and its compatibility with the EPICS control system. The normal conducting cavities operate at both the 1497 MHz accelerating frequency and the sub-harmonic frequency of 499 MHz. To accommodate this, the ne w design will use different receiver-transmitter daughter cards for each frequency. This paper discusses the development of the new RF system and reports on initial results

  2. ER@CEBAF: A test of 5-pass energy recovery at CEBAF

    Energy Technology Data Exchange (ETDEWEB)

    Bogacz, S. A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Douglas, D. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Dubbe, C. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Hutton, A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Michalski, T. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Pilat, F. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Roblin, Y. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Satogata, T. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Spata, M. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Tennant, C. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Tiefenback, M. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Ben-Zvi, I. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hao, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); Korysko, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ptitsyn, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Robert-Demolaize, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Roser, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Thieberger, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tsoupas, N. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-06-06

    Jefferson Lab personnel have broad expertise in the design, commissioning, and operation of multiple energy recovery linacs (ERLs): the CEBAF Front-End Test (early 1990s), CEBAF-ER (2003), the IR Free Electron Laser (FEL) Demo, the IR FEL Upgrade, and the UV FEL Driver (1997-2014). Continued development of this core competency has led to this collaborative proposal to explore the forefronts of ERL technology at high energy in a unique expansion of CEBAF capability to a 5-pass ERL with negligible switchover time and programmatic impact to the CEBAF physics program. Such a capability would enable world-class studies of open issues in high-energy ERL beam dynamics that are relevant to future facilities such as electron-ion colliders (EICs). This proposal requests support from the CEBAF Program Advisory Committee to seek funding for hardware installation, and a prospective 12 days of beam time circa Fall 2018 for commissioning this high-energy multi-pass ERL experiment in CEBAF.

  3. Superconducting Cavity Development for the CEBAF Upgrade

    International Nuclear Information System (INIS)

    I.E. Campisi; J.R. Delayen; L.R. Doolittle; P.Kneisel; J. Mammosser; L. Phillips

    1999-01-01

    Long-term plans for CEBAF at Jefferson Lab call for achieving 12 GeV in the middle of the next decade and 24 GeV after 2010. In support of these plans, an Upgrade Cryomodule, capable of providing more than twice the operating voltage of the existing CEBAF modules within the same length, is being developed. In particular, this requires the development of superconducting cavities capable of consistently operating at gradients above 12 MV/m and Q approximately 10 10 . We have engaged in a complete review of all the processes and procedures involved in the fabrication and assembly of cavities, and are modifying our chemical processing, cleaning, and assembly facilities. While we have retained the cell shape of existing CEBAF cavities, the new superconducting structure will be substantially different in several respects, such as the higher-order-modes damping and the fundamental power coupling systems. Design features and experimental results will be presented

  4. Embedded software for the CEBAF RF Control Module

    International Nuclear Information System (INIS)

    Lahti, G.; Ashkenazi, I.; West, C.; Morgan, B.

    1991-01-01

    The CEBAF accelerator control system employs a distributed computer strategy. As part of this strategy, the RF control sub-system uses 342 RF Control Modules, one for each of four warm section beam forming cavities (i.e., choppers, buncher, capture) and 338 superconducting accelerating cavities. Each control module has its own microprocessor, which provides local intelligence to automatically control over 100 parameters, while keeping the user interface simple. The microprocessor controls analog and digital I/O, including the phase and gradient section, high power amplifier (HPA), and interlocks. Presently, the embedded code is used to commission the 14 RF control modules in the injector. This paper describes the operational experience of this complex real-time control system

  5. Space-charge effects on bunching of electrons in the CEBAF injector

    International Nuclear Information System (INIS)

    Liu, H.

    1997-01-01

    The main injector for the 4 GeV CEBAF accelerator at Thomas Jefferson national accelerator facility was designed to deliver simultaneously three CW electron beams for nuclear physics research. The maximum design current for a single beam from the injector is 100 μA, or 0.2 pC per microbunch at a repetition rate of 499 MHz. It was found through computer simulation that space charge even at a subpicocoulomb level can spoil the bunching of electrons significantly, and some unexpected phenomena observed experimentally could be explained accordingly. This problem arises because of the low-momentum tilt allowed for bunching to preserve low-momentum spread. In this paper, we analyze in detail the space-charge effects on bunching of electrons with the CEBAF injector as an example. Conditions for effective matching of longitudinal phase space in the presence of space charge are discussed. (orig.)

  6. Experiments and simulation of high current operation at CEBAF

    International Nuclear Information System (INIS)

    Merminga, L.; Crawford, K.; Delayen, J.R.; Doolittle, L.; Hovater, C.; Kazimi, R.; Krafft, G.; Reece, C.; Simrock, S.; Tiefenback, M.; Wang, D.X.

    1996-01-01

    The superconducting rf, cw electron accelerator at CEBAF has achieved the design energy of 4 GeV using 5-pass recirculation through a pair of 400 MeV linacs. Stable beam current of 35 μA has been delivered to the Experimental Hall C. The total beam current that has been recirculated so far is 248 μA. Measurements of the performance of the rf control system have been made in both pulsed and cw mode, and a numerical model has been developed which describes the beam-cavity interaction, includes a realistic representation of low level controls, klystron characteristics and microphonic noise. Experimental data and simulation results on transient beam loading, klystron saturation, a new technique for cavity phasing, and heavy beam loading tests are described; in conclusion, an outlook on full current operation is presented

  7. Precision intercomparison of beam current monitors at CEBAF

    International Nuclear Information System (INIS)

    Kazimi, R.; Dunham, B.; Krafft, G.A.; Legg, R.; Liang, C.; Sinclair, C.; Mamosser, J.

    1995-01-01

    The CEBAF accelerator delivers a CW electron beam at fundamental 1497 MHz, with average beam current up to 200 μA. Accurate, stable nonintercepting beam current monitors are required for: setup/control, monitoring of beam current and beam losses for machine protection and personnel safety, and providing beam current information to experimental users. Fundamental frequency stainless steel RF cavities have been chosen for these beam current monitors. This paper reports on precision intercomparison between two such RF cavities, an Unser monitor, and two Faraday cups, all located in the injector area. At the low beam energy in the injector, it is straightforward to verify the high efficiency of the Faraday cups, and the Unser monitor included a wire through it to permit an absolute calibration. The cavity intensity monitors have proven capable of stable, high precision monitoring of the beam current

  8. eDT and Model-based Configuration of 12GeV CEBAF

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Dennison L. [Jefferson Lab, Newport News, VA (United States)

    2015-09-01

    This poster will discuss model-driven setup of CEBAF for the 12GeV era, focusing on the elegant Download Tool (eDT). eDT is a new operator tool that generates magnet design setpoints for various machine energies and pass configurations. eDT was developed in the effort towards a process for reducing machine configuration time and reproducibility by way of an accurate accelerator model.

  9. Research program at CEBAF (II): Report of the 1986 summer Study Group, June 2--August 29, 1986

    International Nuclear Information System (INIS)

    1987-01-01

    This report discusses research performed at the CEBAF accelerator. Topics covered are: single nucleon emission; excited baryons; electromagnetic production of strange nuclear systems; studies in the x-scaling region; weak interactions; particle theory; magnetic spectrometers; real photons; and targets and production processes

  10. Design and Implementation of the CEBAF Element Database

    International Nuclear Information System (INIS)

    Larrieu, Theodore; Slominski, Christopher; Joyce, Michele

    2011-01-01

    With inauguration of the CEBAF Element Database (CED) in Fall 2010, Jefferson Lab computer scientists have taken a first step toward the eventual goal of a model-driven accelerator. Once fully populated, the database will be the primary repository of information used for everything from generating lattice decks to booting front-end computers to building controls screens. A particular requirement influencing the CED design is that it must provide consistent access to not only present, but also future, and eventually past, configurations of the CEBAF accelerator. To accomplish this, an introspective database schema was designed that allows new elements, element types, and element properties to be defined on-the-fly without changing table structure. When used in conjunction with the Oracle Workspace Manager, it allows users to seamlessly query data from any time in the database history with the exact same tools as they use for querying the present configuration. Users can also check-out workspaces and use them as staging areas for upcoming machine configurations. All Access to the CED is through a well-documented API that is translated automatically from original C++ into native libraries for script languages such as perl, php, and TCL making access to the CED easy and ubiquitous. Notice: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce this manuscript for U.S. Government purposes.

  11. ER@CEBAF: Modeling code developments

    Energy Technology Data Exchange (ETDEWEB)

    Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Roblin, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2016-04-13

    A proposal for a multiple-pass, high-energy, energy-recovery experiment using CEBAF is under preparation in the frame of a JLab-BNL collaboration. In view of beam dynamics investigations regarding this project, in addition to the existing model in use in Elegant a version of CEBAF is developed in the stepwise ray-tracing code Zgoubi, Beyond the ER experiment, it is also planned to use the latter for the study of polarization transport in the presence of synchrotron radiation, down to Hall D line where a 12 GeV polarized beam can be delivered. This Note briefly reports on the preliminary steps, and preliminary outcomes, based on an Elegant to Zgoubi translation.

  12. Cryomodule development for the CEBAF upgrade

    International Nuclear Information System (INIS)

    J. R. Delayen; L. R. Doolittle; E. Feldl; J. Hogan; J. Mammosser; V. Nguyen; H. L. Phillips; J. Preble; W. J. Scheider; D. X. Wang; M. Wiseman

    1999-01-01

    Long term plans for CEBAF at Jefferson Lab call for achieving 12 GeV in the middle of the next decade and 24 GeV after 2010. In support of these plans, an Upgrade Cryomodule capable of providing more than three times the voltage of the original CEBAF cryomodule specification within the same length is under development. Development activities have been focused on critical areas thought to have maximum impact on the overall design. These have included the cavity structure, rf power coupling, cavity suspension, alignment, cavity tuning, and beamline interface. It has been found that all design and development areas are tightly coupled and can not be developed independently. Substantial progress has been made toward an integrated design for the Jefferson Lab Upgraded Cryomodule

  13. The CEBAF fiber optic phase reference system

    International Nuclear Information System (INIS)

    Crawford, K.; Simrock, S.; Hovater, C.; Krycuk, A.

    1995-01-01

    The specified phase stability of the CEBAF RF distribution system is 2.9 degree rms per linac. Stability is achieved through the use of a temperature and pressure regulated coaxial drive line. Purpose of the fiber optic phase reference system is to monitor the relative phase at the beginning and ending of this drive line, between linacs, injector and separator to determine drift due to ambient temperature fluctuations. The system utilizes an Ortel 1310 nm single mode laser driving Sumitumo optical fiber to distribute a reference signal at 1497 MHz. Phase of this reference signal is compared to the 1427 MHz (LO) and the 70 MHz (IF) via a 360 degree phase detector. The detected information is then routed to the CEBAF control system for display with a specified resolution of ±0.2 degree over a 20 degree phase delta

  14. CEBAF: First steps towards physics

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1987-10-15

    A Programme Advisory Committee for the Continuous Electron Beam Accelerator Facility, where construction began at Newport News in the US in February of this year, will consider letters of intent for the initial experiments when it meets in October. Actual physics proposals will be discussed next April. Completion of the 0.5 to 4 (or 6) GeV machine is scheduled for 1992 and sophisticated experimental stations will need to be ready to make use of the refined abilities of the accelerated beams.

  15. Elastic form factors at higher CEBAF energies

    Energy Technology Data Exchange (ETDEWEB)

    Petratos, G.G. [Kent State Univ., OH (United States)

    1994-04-01

    The prospects for elastic scattering from few body systems with higher beam energies at CEBAF is presented. The deuteron and{sup 3}He elastic structure functions A(Q{sup 2}) can be measured at sufficiently high momentum transfers to study the transition between the conventional meson-nucleon and the constituent quark-gluon descriptions. Possible improvements in the proton magnetic form factor data are also presented.

  16. Analog techniques in CEBAF's RF control system

    International Nuclear Information System (INIS)

    Hovater, C.; Fugitt, J.

    1989-01-01

    Recent developments in high-speed analog technology have progressed into the areas of traditional RF technology. Diode related devices are being replaced by analog IC's in the CEBAF RF control system. Complex phase modulators and attenuators have been successfully tested at 70 MHz. They have three advantages over existing technology: lower cost, less temperature sensitivity, and more linearity. RF signal conditioning components and how to implement the new analog IC's will be covered in this paper. 4 refs., 5 figs

  17. Analog techniques in CEBAF'S RF control system

    International Nuclear Information System (INIS)

    Hovater, C.; Fugitt, J.

    1989-01-01

    Recent developments in high-speed analog technology have progressed into the areas of traditional rf technology. Diode-related devices are being replaced by analog IC's in the CEBAF rf control system. Complex phase modulators and attenuators have been successfully tested at 70 MHz. They have three advantages over existing technology: lower cost, less temperature sensitivity, and more linearity. Rf signal conditioning components and how to implement the new analog IC's will be covered in this paper. 4 refs., 5 figs

  18. Slow beam raster system at CEBAF

    International Nuclear Information System (INIS)

    Yan, C.; Beaufait, J.; Carlini, R.; Cuevas, C.; Vulcan, W.; Wines, R.

    1994-01-01

    A bedstead air-core raster magnet is being installed now, it will be used at CEBAF to scan the beam on the Hall C polarized target and the beam dump with fixed frequency 60 Hz in horizontal, 103.4 Hz in vertical. The x and y raster magnets are driven by Variac transformer and SUMIT-OMO inverter respectively. Both of them provide an approximate sine current waveform with peak current 20 A, corresponding to a maximum deflection angle 1 mr

  19. CEBAF/SURA 1985 Summer Workshop

    International Nuclear Information System (INIS)

    Crannel, H.

    1985-12-01

    The 1985 Summer Workshop began a new phase of planning for the experimental program at CEBAF. One goal of the Workshop was to define and describe options for equipping the CEBAF and stations with experimental equipment. Starting with an initial list of options which grew out of discussions during the Winter of 1984 and the Spring of 1985, the five working groups met during the Workshop and developed their final reports, included in these proceedings. The program of the Workshop consisted of invited talks on both theoretical and experimental topics, and working group meetings. The five working groups, include: Magnetic Spectrometers; Large Acceptance Detectors and Low Intensity Beams; Internal Targets; Positrons; Theory. These proceedings begin with an overview of CEBAF, and a report on progress made by the Magnetic Spectrometer and Internal Target Working Groups prior to the Workshop. The next part contains the invited talks, presented in the order which they were given during the week. The final reports of the five working groups follow this, and the proceedings conclude with papers contributed to the Workshop

  20. Software Tools for Emittance Measurement and Matching for 12 GeV CEBAF

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Dennis L. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2016-05-01

    This paper discusses model-driven setup of the Continuous Electron Beam Accelerator Facility (CEBAF) for the 12GeV era, focusing on qsUtility. qsUtility is a set of software tools created to perform emittance measurements, analyze those measurements, and compute optics corrections based upon the measurements.qsUtility was developed as a toolset to facilitate reducing machine configuration time and reproducibility by way of an accurate accelerator model, and to provide Operations staff with tools to measure and correct machine optics with little or no assistance from optics experts.

  1. A Compton polarimeter for CEBAF Hall A

    Energy Technology Data Exchange (ETDEWEB)

    Bardin, G; Cavata, C; Frois, B; Juillard, M; Kerhoas, S; Languillat, J C; Legoff, J M; Mangeot, P; Martino, J; Platchkov, S; Rebourgeard, P; Vernin, P; Veyssiere, C; CEBAF Hall A Collaboration

    1994-09-01

    The physic program at CEBAF Hall A includes several experiments using 4 GeV polarized electron beam: parity violation in electron elastic scattering from proton and {sup 4}He, electric form factor of the proton by recoil polarization, neutron spin structure function at low Q{sup 2}. Some of these experiments will need beam polarization measurement and monitoring with an accuracy close to 4%, for beam currents ranging from 100 nA to 100 microA. A project of a Compton Polarimeter that will meet these requirements is presented. It will comprise four dipoles and a symmetric cavity consisting of two identical mirrors. 1 fig., 10 refs.

  2. Research and Development for an Alternative RF Source Using Magnetrons in CEBAF

    Science.gov (United States)

    Jacobs, Andrew

    2016-09-01

    At Jefferson Lab, klystrons are currently used as a radiofrequency (RF) power source for the 1497 MHz Continuous Electron Beam Accelerator Facility (CEBAF) Continuous Wave (CW) system. A drop-in replacement for the klystrons in the form of a system of magnetrons is being developed. The klystron DC-RF efficiency at CEBAF is 35-51% while the estimated magnetron efficiency is 80-90%. Thus, the introduction of magnetrons to CEBAF will have enormous benefits in terms of electrical power saving. The primary focus of this project was to characterize a magnetron's frequency pushing and pulling curves at 2.45 GHz with stub tuner and anode current adjustments so that a Low Level RF controller for a new 1.497 GHz magnetron can be built. A Virtual Instrument was created in LabVIEW, and data was taken. The resulting data allowed for the creation of many constant lines of frequency and output power. Additionally, the results provided a characterization of magnetron oven temperature drift over the operation time and the relationship between anode current and frequency. Using these results, the control model of different variables and their feedback or feedforward that affect the frequency pushing and pulling of the magnetron is better developed. Department of Energy, Science Undergraduate Laboratory Internships, and Jefferson Lab.

  3. Design and implementation of the CEBAF element database

    International Nuclear Information System (INIS)

    Larrieu, T.; Joyce, M.; Slominski, C.

    2012-01-01

    With the inauguration of the CEBAF Element Database (CED) in Fall 2010, Jefferson Lab computer scientists have taken a step toward the eventual goal of a model-driven accelerator. Once fully populated, the database will be the primary repository of information used for everything from generating lattice decks to booting control computers to building controls screens. A requirement influencing the CED design is that it provide access to not only present, but also future and past configurations of the accelerator. To accomplish this, an introspective database schema was designed that allows new elements, types, and properties to be defined on-the-fly with no changes to table structure. Used in conjunction with Oracle Workspace Manager, it allows users to query data from any time in the database history with the same tools used to query the present configuration. Users can also check-out workspaces to use as staging areas for upcoming machine configurations. All Access to the CED is through a well-documented Application Programming Interface (API) that is translated automatically from original C++ source code into native libraries for scripting languages such as perl, php, and TCL making access to the CED easy and ubiquitous. (authors)

  4. CEBAF/SURA 1984 summer workshop: Proceedings

    International Nuclear Information System (INIS)

    Gross, F.; Whitney, R.R.

    1984-11-01

    This report discusses the following topics: Summary: Magnetic Spectrometer Working Group; Workshop Report: Internal Targets and Tagged Photons; Nucleon Physics with Chromodynamics: From High Q 2 to Baryon Spectroscopy to Nuclear Physics; Quark Signatures in Nuclear Physics; What Can We Learn About the Three-Nucleon Wave Functions from High Energy Electrons; Coincidence and Polarization Measurements with High-Energy Electrons; NPAS -- a Program of Nuclear Physics at SLAC; Spectrometers; Polarized Gas Targets in Electron Rings; Photonuclear Experiments Using Large Acceptance Detectors; 4 π Detectors; Magnetic Spectrometer Working Group Report; Workshop Report: Tagged Photons - Low Current Electron Beams and Large Acceptance - 4 π Detectors; Positron Beams at CEBAF; Lampshade Magnet for a Large-Aperture Detector; Meson Exchange in Relativistic Quark Models; Electron Scattering from Discrete Low-Lying Levels of 13 C at High Momentum Transfer; NN Potential With a Six Quark Core from the Constituent Quark Model; A Study of (e,e'N) Reactions from Nuclear Targets; Study of Complex Nuclei Using Internal Targets at CEBAF; The Kaon-Nucleon Interaction in a Quark Potential Model; and Current Conservation and Magnetic Form Factors of 3 He, 3 H

  5. Early operating and reliability experience with the CEBAF DC magnet power supplies

    International Nuclear Information System (INIS)

    Merz, W.; Flood, R.; Martin, E.J.; O'Sullivan, M.

    1996-01-01

    The CEBAF accelerator is a five pass, recirculating, CW electron linear accelerator. There are a total of nine recirculation arcs connecting the two linacs. Three experimental halls are serviced by the accelerator through separate transport channels. The magnet powering system for CEBAF consists of approximately 2000 independent control channels. About 1850 of these channels are low current, trim magnet power supplies. There are 28 higher power supplies used to energize the major bending elements. Over one hundred, 20 amp, active shunts are used to vary current in selected magnets in the major dipole strings. The majority of the magnetic elements are concentrated in the arcs and transport channels. The correction dipoles, quadrupoles and sextupoles are each powered individually be a dedicated trim power supply channel. The arc and extraction channel dipoles are powered in series strings by the high powered supplies, known locally at CEBAF as 'box power supplies'. Arc loads consist of some 30--40 magnets in series. Transport channel, path length control doglegs and septa box power supplies have loads ranging from 1 to 10 magnets. Shunts are installed on virtually all loads where two or more magnets are in series. At this time, 95% of the power supplies are installed and commissioned. In the past twelve months, beginning in May 1994, approximately 1200 trim magnet power supplies have been checked out. During this same period approximately 22 box power supplies and 100 shunts have been made operational. Full operation of the equipment has only been under way since early 1995. While this operation is only just beginning, much has been learned based on the reliability performance seen so far. The remainder of this paper describes the systems mentioned, their reliability problems, the fixes implemented to date, and some plans for the future. 6 refs., 3 tabs

  6. Frequency tuning of the CEBAF upgrade cavities

    International Nuclear Information System (INIS)

    J.R. Delayen; L. Doolittle; E. Feldl; V. Nguyen; W. Sachleben

    1999-01-01

    Long-term plans for CEBAF at Jefferson Lab calls for achieving 12 GeV in the middle of the next decade and 24 GeV after 2010. In support of these plans, an Upgrade Cryomodule capable of providing more than twice the voltage of the existing ones is under development. One requirement is to operate the superconducting cavities, which are 40% longer than existing ones, at 2.5 times the original design gradient with the same amount of rf power. This puts stringent requirements on the accuracy of the frequency tuner: range of 400 kHz and resolution of 1 Hz. A new tuner design to meet these requirements is under development. This system avoids problem areas of previous designs by holding to the principles of not placing moving parts in the vacuum and/or low temperature space, and of having all drive components readily accessible for maintenance and replacement without cryomodule warm-up

  7. A proposed high-power UV industrial demonstration laser at CEBAF

    International Nuclear Information System (INIS)

    Benson, S.V.; Bisognano, J.J.; Bohn, C.L.

    1996-01-01

    The Laser Processing Consortium, a collaboration of industries, universities, and the Continuous Electron Beam Accelerator Facility (CEBAF) in Newport News, Virginia, has proposed building a demonstration industrial processing laser for surface treatment and micro-machining. The laser is a free-electron laser (FEL) with average power output exceeding 1 kW in the ultraviolet (UV). The design calls for a novel driver accelerator that recovers most of the energy of the exhaust electron beam to produce laser light with good wall-plug efficiency. The laser and accelerator design use technologies that are scalable to much higher power. The authors describe the critical design issues in the laser such as the stability, power handling, and losses of the optical resonator, and the quality, power, and reliability of the electron beam. They also describe the calculated laser performance. Finally progress to date on accelerator development and resonator modeling will be reported

  8. A proposed high-power UV industrial demonstration laser at CEBAF

    International Nuclear Information System (INIS)

    Benson, S.V.; Bisognano, J.J.; Bohn, C.L.

    1996-01-01

    The Laser Processing Consortium, a collaboration of industries, universities, and the Continuous Electron Beam Accelerator Facility (CEBAF) in Newport News, Virginia, has proposed building a demonstration industrial processing laser for surface treatment and micro-machining. The laser is a free-electron laser (FEL) with average power output exceeding 1 kW in the ultraviolet (UV). The design calls for a novel driver accelerator that recovers most of the energy of the exhaust electron beam to produce laser light with good wall-plug efficiency. The laser and accelerator design use technologies that are scalable to much higher power. The authors will describe the critical design issues in the laser such as the stability, power handling, and losses of the optical resonator, and the quality, power, and reliability of the electron beam. They will also describe the calculated laser performance. Finally progress to date on accelerator development and resonator modeling will be reported

  9. The CEBAF Separator Cavity Resonance Control System

    CERN Document Server

    Wissmann, Mark J; Hovater, Curt; Plawski, Tomasz

    2005-01-01

    The CEBAF energy upgrade from 6 GeV to 12GeV will increase the range of beam energies available to the experimental halls. RF deflection cavities (separators) are used to direct the electron beam to the three experimental halls. Consequently with the increase in RF separator cavity gradient needed for the higher energies, RF power will also increase requiring the cavities to have active resonance control. At the 6 GeV energy, the cavities are tuned mechanically and then stabilized with Low Conductivity Water (LCW), which is maintained at constant temperature of 95o Fahrenheit. This is no longer feasible and an active resonance control system, that controls both water temperature and flow has been built. The system uses a commercial PLC with embedded PID controls to control water temperature and flow to the cavities. The system allows the operator to remotely adjust temperature/flow and consequently cavity resonance for the full range of beam energies. Ultimately closed loop control will be maintained by monit...

  10. The CEBAF separator cavity resonance control system

    International Nuclear Information System (INIS)

    M. Wissmann; C. Hovater; A. Guerra; T. Plawski

    2005-01-01

    The CEBAF energy upgrade will increase the maximum beam energy from 6 GeV to 12 GeV available to the experimental halls. RF deflection cavities (separators) are used to direct the electron beam to the three halls. The resulting increase in RF separator cavity gradient and subsequent increase in RF power needed for these higher energies will require the cavities to have active resonance control. Currently, at the present 4 to 6 GeV energies, the cavities are tuned mechanically and then stabilized with Low Conductivity Water (LCW) which is maintained at a constant temperature of 95 Fahrenheit. This approach is no longer feasible and an active resonance control system that controls both water temperature and flow has been designed and built. The system uses a commercial PLC with embedded PID controls to regulate water temperature and flow to the cavities. The system allows the operator to remotely adjust temperature/flow and consequently cavity resonance for the full range of beam energies. Ultimately, closed loop control will be maintained by monitoring each cavity's reflected power. This paper describes this system

  11. Parity violation workshop: CEBAF [Continuous Electron Beam Accelerator Facility

    International Nuclear Information System (INIS)

    Walecka, J.D.

    1986-01-01

    This paper discusses the use of electron scattering experiments for exploring parity violation in the nuclear domain. It is shown how such experiments can test the structure of strong interactions, the local gauge theory quantum chromodynamics based on color, and the unified gauge theory of electroweak interactions. 14 refs., 13 figs., 1 tab

  12. CEBAF 200 kV Inverted Electron Gun

    International Nuclear Information System (INIS)

    Grames, J.M.; Adderley, P.A.; Clark, J.; Hansknecht, J.; Poelker, M.; Stutzman, M.L.; Suleiman, R.; Surles-Law, K.E.L.

    2011-01-01

    Two DC high voltage GaAs photoguns have been built at Jefferson Lab based on a compact inverted insulator design. One photogun provides the polarized electron beam at CEBAF and operates at 130 kV bias voltage. The other gun is used for high average current lifetime studies at a dedicated test facility and has been operated at bias voltage up to 225 kV. The advantages of higher DC voltage for CEBAF include reduced space-charge emittance growth and the potential for prolonged photocathode lifetime. However, a consequence of operating at higher voltages is the increased likelihood of field emission or breakdown, both of which are unacceptable. Highlights of the R and D studies leading toward a production 200keV GaAs photogun for CEBAF will be presented.

  13. Measuring spin-dependent structure functions at CEBAF

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, A. [Universitaet Frankfurt (Germany)

    1994-04-01

    The author analyses whether CEBAF with a 10 GeV beam could contribute significantly to the understanding of spin-dependent deep-inelastic scattering as well as semi-inclusive reactions. The main advantage of CEBAF is the much better attainable statistics, its great disadvantage its comparably low energy, which limits the accessible x-range to about 0.15 to 0.7. Within these constraints CEBAF could provide (1) high precision data which would be very valuable to understand the Q{sup 2} dependence of the spin-dependent structure functions g{sub 1}(x) and G{sub 2}(x) and (2) the by far most precise determination of the third moments of g{sub 1}(x) and g{sub 2}(x) the latter of which the author argues to be related to a fundamental property of the nucleon.

  14. Measuring spin-dependent structure functions at CEBAF

    International Nuclear Information System (INIS)

    Schaefer, A.

    1994-01-01

    The author analyses whether CEBAF with a 10 GeV beam could contribute significantly to the understanding of spin-dependent deep-inelastic scattering as well as semi-inclusive reactions. The main advantage of CEBAF is the much better attainable statistics, its great disadvantage its comparably low energy, which limits the accessible x-range to about 0.15 to 0.7. Within these constraints CEBAF could provide (1) high precision data which would be very valuable to understand the Q 2 dependence of the spin-dependent structure functions g 1 (x) and G 2 (x) and (2) the by far most precise determination of the third moments of g 1 (x) and g 2 (x) the latter of which the author argues to be related to a fundamental property of the nucleon

  15. Field emitted electron trajectories for the CEBAF cavity

    International Nuclear Information System (INIS)

    Yunn, B.C.; Sundelin, R.M.

    1993-06-01

    Electromagnetic fields of the superconducting 5-cell CEBAF cavity with its fundamental power coupler are solved numerically with URMEL and MAFIA codes. Trajectories of field emitted electrons following the Fowler-Nordheim relation are studied with a numerical program which accepts the URMEL/MAFIA fields. Emission sites and gradients are determined for those electrons which can reach the cold ceramic window either directly or by an energetic backscattering. The peak and average impact energy and current are found. The generation of dark current by field emitted electrons has also been studied, and its relevance to CEBAF operation is briefly discussed

  16. Mechanical and Thermal Design of the CEBAF Hall A Beam Calorimeter

    CERN Document Server

    Bevins, Michael E; Degtiarenko, Pavel; Dillon-Townes, Lawrence A; Freyberger, Arne; Gilman, Ronald; Saha, Arun; Slachtouski, Stephanie

    2005-01-01

    A calorimeter has been proposed to provide 0.5% - 1.0% absolute measurements of beam current in the Hall A end station of the Thomas Jefferson National Accelerator Facility (JLab) CEBAF machine. Silver and copper calorimeters built in the 1960's achieved precisions of about 1%. Modern powder metallurgy processes have produced high density, high thermal conductivity tungsten-copper composite materials that will minimize beam loss while maintaining a rapid thermal response time. Heat leaks will be minimized by mounting the mass in vacuum on glass ceramic mounts. A conduction cooling scheme utilizes an advanced carbon fiber compliant thermal interface material. Transient finite difference and finite element models were developed to estimate heat leaks and thermal response times.

  17. Automatic pumpdown of the 2K cold compressors for the CEBAF central helium liquefier

    International Nuclear Information System (INIS)

    Bevins, B.S.; Chronis, W.C.; Keesee, M.S.

    1996-01-01

    The 2K system at CEBAF includes four stages of centrifugal cold compressors that operate between a suction pressure of 0.031 atm and a discharge of ∼1 atm. Starting the cold compressors and pumping the system down to operating pressure is a complex and time consuming operation. Many months of rigorous testing were required to develop a reliable startup procedure. This procedure has been automated through the development of an Autopumpdown program that intelligently coordinates the necessary steps across the boundaries of the existing cryogenic and accelerator control systems. this program has greatly reduced both the time and effort required to recover from failures and restart the system. The paper describes the requirements addressed by the program, the steps it takes while operating, the historical development of the program, the spin-off benefits, and the course of anticipated future developments

  18. Automatic pumpdown of the 2K cold compressors for the CEBAF central helium liquefier

    International Nuclear Information System (INIS)

    Bevins, B.S.; Chronis, W.C.; Keesee, M.S.

    1996-01-01

    The 2K system at CEBAF includes four stages of centrifugal cold compressors that operate between a suction pressure of 0.031 atm and a discharge of ∼1 atm. Starting the cold compressors and pumping the system down to operating pressure is a complex and time consuming operation. Many months of rigorous testing were required to develop a reliable startup procedure. This procedure has been automated through the development of an Autopumpdown program that intelligently coordinates the necessary steps across the boundaries of the existing cryogenic and accelerator control systems. This program has greatly reduced both the time and effort required to recover from failures and restart the system. The paper describes the requirements addressed by the program, the steps it takes while operating, the historical development of the program, the spin-off benefits, and the course of anticipated future developments

  19. Commissioning and Operational Experience With an Intermediate Upgrade Cryomodule for the CEBAF 12 GeV Upgrade

    International Nuclear Information System (INIS)

    Thomas Powers; Davis, G.; Michael Drury; Christiana Grenoble; Hovater, J.; Lawrence King; Tomasz Plawski; Joseph Preble

    2005-01-01

    Three cryomodules have been designed and built as intermediate prototypes for the CEBAF 12 GeV upgrade. This paper will discuss the commissioning and operational experience with the second of these cryomodules, which was installed and commissioned in the Jefferson Lab 10 kW Free Electron Laser Facility. Within the cryomodule are eight 7-cell, 1497 MHz cavities. It was designed to accelerate 1 mA of beam in excess of 70 MV and to have the same footprint as a standard CEBAF cryomodule. The cryomodule was installed in parallel with the FEL beam line in the spring of 2004 and characterized simultaneous with beam delivery. It was installed in the beam line in the early summer of 2004 and has since been operated as part of an energy recovered linac with 5 mA of beam current and 75 MV accelerating gradient for extended periods of time. Additionally, it was operated at 1 mA of beam current and 80 MV of accelerating gradient for several hours without a trip. In the latter operating mode the beam current was limited by the injector setup

  20. Commissioning and operation of the CEBAF end station refrigeration system

    International Nuclear Information System (INIS)

    Arenius, D.; Bevins, B.; Chronis, W.C.; Ganni, V.

    1996-01-01

    The CEBAF End Station Helium Refrigerator (ESR) System provides refrigeration at 80 K, 20 K and 4.5 K to three End Station experimental halls. The facility consists of a two stage helium screw compressor system, 4.5 K refrigerator, cryogen distribution valve box, and transfer lines to the individual experimental halls. The 4.5 K cold box and compressors were originally part of the ESCAR 1500 W, 4 K refrigeration system at Lawrence Berkeley Laboratory which was first commissioned in 1977. The compressors, 4.5 K cold box, and control system design were modified to adapt the plant for the requirements of the CEBAF experimental halls. Additional subsystems of cryogen distribution, transfer lines, warm gas management, and computer control interface were added. This paper describes the major plant subsystems, modifications, operational experiences and performance

  1. Performance of the CEBAF Arc Beam Position Monitors

    International Nuclear Information System (INIS)

    A.S. Hofler; B.A. Bowling; C.S. Higgins; P.K. Kloeppel; G.A. Krafft; K.L. Mahoney

    1993-01-01

    The first three quarters of the first CEBAF arc have been instrumented with beam position monitors. Thirty-seven monitors (of 450) have been installed and their noise measured. Resolution of 100 mu-m was obtained at the lowest operating current of 1 mu-A. The update time of the system is 1 sec, limited by computer interfacing with a potential bandwidth of greater than 10 kHz

  2. Microphonics Testing of the CEBAF Upgrade 7-Cell Cavity

    International Nuclear Information System (INIS)

    G.K. Davis; J.R. Delayen; M. Drury; T. Hiatt; C. Hovater; T. Powers; J. Preble

    2001-01-01

    An upgrade cryomodule is being developed for CEBAF at Jefferson Lab. In support of this effort, vibration testing was performed on a single SRF cavity at cryogenic temperature in a Horizontal Test Bed. The tests included response to excitation from background vibration, swept sinusoids, high-power RF pulses, and mechanical impulses. Test procedures, apparatus, and results are presented, along with a description of planned follow-up tests

  3. Object oriented run control for the CEBAF data acquisition system

    International Nuclear Information System (INIS)

    Quarrie, D.R.; Heyes, G.; Jastrzembski, E.; Watson, W.A. III

    1992-01-01

    After an extensive evaluation, the Eiffel object oriented language has been selected for the design and implementation of the run control portion of the CEBAF Data Acquisition System. The OSF/Motif graphical user interface toolkit and Data Views process control system have been incorporated into this framework. in this paper, the authors discuss the evaluation process, the status of the implementation and the lessons learned, particularly in the use of object oriented techniques

  4. Improvement of the noise figure of the CEBAF switched electrode electronics BPM system

    International Nuclear Information System (INIS)

    Powers, T.

    1998-01-01

    The Continuous Electron Beam Accelerator Facility (CEBAF) is a high-intensity continuous wave electron accelerator for nuclear physics located at Thomas Jefferson National Accelerator Facility. A beam energy of 4 GeV is achieved by recirculating the electron beam five times through two anti-parallel 400 MeV linacs. In the linacs, where there is recirculated beam, the BPM specifications must be met for beam intensities between 1 and 100 μA. In the transport lines the BPM specifications must be met for beam intensities between 100 nA and 200 μA. To avoid a complete redesign of the existing electronics, we investigated ways to improve the noise figure of the linac BPM switched-electrode electronics (SEE) so that they could be used in the transport lines. We found that the out-of-band noise contributed significantly to the overall system noise figure. This paper will focus on the source of the excessive out-of-band noise and how it was reduced. The development, commissioning and operational results of this low noise variant of the linac style SEE BPMs as well as techniques for determining the noise figure of the rf chain will also be presented. copyright 1998 American Institute of Physics

  5. Applying AN Object-Oriented Database Model to a Scientific Database Problem: Managing Experimental Data at Cebaf.

    Science.gov (United States)

    Ehlmann, Bryon K.

    Current scientific experiments are often characterized by massive amounts of very complex data and the need for complex data analysis software. Object-oriented database (OODB) systems have the potential of improving the description of the structure and semantics of this data and of integrating the analysis software with the data. This dissertation results from research to enhance OODB functionality and methodology to support scientific databases (SDBs) and, more specifically, to support a nuclear physics experiments database for the Continuous Electron Beam Accelerator Facility (CEBAF). This research to date has identified a number of problems related to the practical application of OODB technology to the conceptual design of the CEBAF experiments database and other SDBs: the lack of a generally accepted OODB design methodology, the lack of a standard OODB model, the lack of a clear conceptual level in existing OODB models, and the limited support in existing OODB systems for many common object relationships inherent in SDBs. To address these problems, the dissertation describes an Object-Relationship Diagram (ORD) and an Object-oriented Database Definition Language (ODDL) that provide tools that allow SDB design and development to proceed systematically and independently of existing OODB systems. These tools define multi-level, conceptual data models for SDB design, which incorporate a simple notation for describing common types of relationships that occur in SDBs. ODDL allows these relationships and other desirable SDB capabilities to be supported by an extended OODB system. A conceptual model of the CEBAF experiments database is presented in terms of ORDs and the ODDL to demonstrate their functionality and use and provide a foundation for future development of experimental nuclear physics software using an OODB approach.

  6. Simulation of a Positron Source for CEBAF

    International Nuclear Information System (INIS)

    S. Golge; A. Freyberger; C. Hyde-Wright

    2007-01-01

    A positron source for the 6 GeV (or the proposed 12 GeV upgrade) recirculating linacs at Jefferson Lab is presented. The proposed 100nA CW positron source has several unique characteristics; high incident beam power (100kW), 10 MeV incident electron beam energy, CW incident beam and CW production. Positron production with 10 MeV electrons has several advantages; the energy is below neutron threshold so the production target will not become activated during use and the absolute energy spread is bounded by the low incident energy. These advantages are offset by the large angular distribution of the outgoing positrons. Results of simulations of the positron production, capture, acceleration and injection into the recirculating linac are presented. Energy flow and thermal management of the production target present a challenge and are included in the simulations

  7. Analysis of mechanical fabrication experience with CEBAF's production SRF cavities

    International Nuclear Information System (INIS)

    Mammosser, J.; Kneisel, P.; Benesch, J.

    1993-06-01

    CEBAF has received a total of 360 five-cell niobium cavities, the largest group of industrially fabricated superconducting cavities so far. An extensive data base exists on the fabrication, surface treatment, assembly and cavity performance parameters. Analysis of the mechanical features of the cavities includes the following: the spread in fabrication tolerances of the cells derived from field profiles of the ''as fabricated'' cavities and the ''as fabricated'' external Q-values of the fundamental power coupler compared to dimensional deviations. A comparison is made of the pressure sensitivity of cavities made of materials from different manufacturers between 760 torr (4.2 K) and 23 torr (2 K)

  8. Research program at CEBAF (III): Report of the 1987 summer study group, June 1--August 28, 1987

    International Nuclear Information System (INIS)

    Burkert, V.; Gross, F.; Mecking, B.; Mougey, J.; Nanda, S.; Whitney, R.

    1988-01-01

    An informal Study Group consisting of the CEBAF scientific staff and about 43 visiting scientists met during the summer of 1987 to discuss issues of importance to planning the CEBAF scientific program. The contributions to this volume grew out of these discussions, and out of additional discussion with the User community and with CEBAF's new Associate Director for Research, John Domingo, which extended into the fall of 1987. Reports of the 1985 and 1986 Summer Study Groups have been previously published by CEBAF under the title Research Programs at CEBAF (RPAC) and hence it is appropriate to refer to this volume as RPAC III. The contributions to this volume have been organized into the following six general areas reflecting the focus of principle activities during this period: High Resolution Spectrometers; Large Acceptance Spectrometer; Out-of-Plane Experiments at CEBAF; Neutron Detection at CEBAF; Illustrative Experiments and Experimental Design; and Theory

  9. Nonperturbative QCD and elastic processes at CEBAF energies

    Energy Technology Data Exchange (ETDEWEB)

    Radyushkin, A.V. [Old Dominion Univ., Norfolk, VA (United States)]|[Continuous Electron Beam Accelerator Facility, Newport News, VA (United States)

    1994-04-01

    The author outlines how one can approach nonperturbative aspects of the QCD dynamics studying elastic processes at energies accessible at upgraded CEBAF. The author`s point is that, in the absence of a complete theory of the nonperturbative effects, a possible way out is based on a systematic use of the QCD factorization procedure which separates theoretically understood ({open_quotes}known{close_quotes}) short-distance effects and nonperturbative ({open_quotes}unknown{close_quotes}) long-distance ones. The latter include hadronic distribution amplitudes, soft components of hadronic form factors etc. Incorporating the QCD sum rule version of the QCD factorization approach, one can relate these nonperturbative functions to more fundamental objects, vacuum condensates, which accumulate information about the nonperturbative structure of the QCD vacuum. The emerging QCD sum rule picture of hadronic form factors is characterized by a dominant role of essentially nonperturbative effects in the few GeV region, with perturbative mechanisms starting to show up for momentum transfers Q{sup 2} closer to 10 GeV{sup 2} and higher. Thus, increasing CEBAF energy provides a unique opportunity for a precision study of interplay between the perturbative and nonperturbative phenomena in the QCD description of elastic processes.

  10. Nonperturbative QCD and elastic processes at CEBAF energies

    International Nuclear Information System (INIS)

    Radyushkin, A.V.

    1994-01-01

    The author outlines how one can approach nonperturbative aspects of the QCD dynamics studying elastic processes at energies accessible at upgraded CEBAF. The author's point is that, in the absence of a complete theory of the nonperturbative effects, a possible way out is based on a systematic use of the QCD factorization procedure which separates theoretically understood (open-quotes knownclose quotes) short-distance effects and nonperturbative (open-quotes unknownclose quotes) long-distance ones. The latter include hadronic distribution amplitudes, soft components of hadronic form factors etc. Incorporating the QCD sum rule version of the QCD factorization approach, one can relate these nonperturbative functions to more fundamental objects, vacuum condensates, which accumulate information about the nonperturbative structure of the QCD vacuum. The emerging QCD sum rule picture of hadronic form factors is characterized by a dominant role of essentially nonperturbative effects in the few GeV region, with perturbative mechanisms starting to show up for momentum transfers Q 2 closer to 10 GeV 2 and higher. Thus, increasing CEBAF energy provides a unique opportunity for a precision study of interplay between the perturbative and nonperturbative phenomena in the QCD description of elastic processes

  11. Rf system modeling for the high average power FEL at CEBAF

    International Nuclear Information System (INIS)

    Merminga, L.; Fugitt, J.; Neil, G.; Simrock, S.

    1995-01-01

    High beam loading and energy recovery compounded by use of superconducting cavities, which requires tight control of microphonic noise, place stringent constraints on the linac rf system design of the proposed high average power FEL at CEBAF. Longitudinal dynamics imposes off-crest operation, which in turn implies a large tuning angle to minimize power requirements. Amplitude and phase stability requirements are consistent with demonstrated performance at CEBAF. A numerical model of the CEBAF rf control system is presented and the response of the system is examined under large parameter variations, microphonic noise, and beam current fluctuations. Studies of the transient behavior lead to a plausible startup and recovery scenario

  12. Accelerators

    CERN Multimedia

    CERN. Geneva

    2001-01-01

    The talk summarizes the principles of particle acceleration and addresses problems related to storage rings like LEP and LHC. Special emphasis will be given to orbit stability, long term stability of the particle motion, collective effects and synchrotron radiation.

  13. Status report on the development of a high-power UV/IR FEL at CEBAF

    Energy Technology Data Exchange (ETDEWEB)

    Benson, S.; Bohn, C.; Dylla, H.F. [Continuous Electron Beam Accelerator Facility, Newport News, VA (United States)] [and others

    1995-12-31

    Last year we presented a design for a kilowatt industrial UV FEL based on a superconducting RF accelerator delivering 5 mA of electron-beam current at 200 MeV with energy recovery to enhance efficiency. Since then, we have progressed toward resolving several issues associated with that design. More exact simulations of the injector have resulted in a more accurate estimate of the injector performance. A new injection method has reduced the longitudinal and transverse emittance at the linac entrance. A more compact lattice has been designed for the UV FEL, and a new recirculation scheme has been identified which greatly increases the threshold for longitudinal instabilities. We decided to use a wiggler from the Advanced Photon Source which leads to a robust high-gain FEL. Analysis of the stability of an RF control system based on CEBAF control modules indicates that only minor modifications will be needed to apply them to this FEL. Detailed magnet specifications, vacuum-chamber beam apertures, and diagnostic specifications have been developed for the recirculation arcs. The design of the optical cavity has been conceptualized, and control systems have been devised to regulate mirror distortion. A half-scale model of one of the end-corner cubes has been built and tested. Finally, three-dimensional simulations have been carried out which indicate that the FEL should exceed its minimum design goals with adequate performance margin.

  14. High Accuracy Beam Current Monitor System for CEBAF'S Experimental Hall A

    International Nuclear Information System (INIS)

    J. Denard; A. Saha; G. Lavessiere

    2001-01-01

    CEBAF accelerator delivers continuous wave (CW) electron beams to three experimental Halls. In Hall A, all experiments require continuous, non-invasive current measurements and a few experiments require an absolute accuracy of 0.2 % in the current range from 1 to 180 (micro)A. A Parametric Current Transformer (PCT), manufactured by Bergoz, has an accurate and stable sensitivity of 4 (micro)A/V but its offset drifts at the muA level over time preclude its direct use for continuous measurements. Two cavity monitors are calibrated against the PCT with at least 50 (micro)A of beam current. The calibration procedure suppresses the error due to PCT's offset drifts by turning the beam on and off, which is invasive to the experiment. One of the goals of the system is to minimize the calibration time without compromising the measurement's accuracy. The linearity of the cavity monitors is a critical parameter for transferring the accurate calibration done at high currents over the whole dynamic range. The method for measuring accurately the linearity is described

  15. The JLab 12 GeV Energy Upgrade of CEBAF for QCD and Hadronic Physics

    International Nuclear Information System (INIS)

    Lawrence Cardman; Leigh Harwood

    2007-01-01

    CEBAF at Jefferson Lab is a 5-pass, recirculating cw electron linac operating at ∼6 GeV and devoted to basic research in nuclear physics. The 12 GeV Upgrade is a major project, sponsored by the DOE Office of Nuclear Physics, that will expand its research capabilities substantially by doubling the maximum energy and adding major new experimental apparatus. We anticipate that the project will receive Critical Decision 2 approval this year and begin construction in 2008. The research program motivating the Upgrade includes: the study of hybrid mesons, which involve excited states of the glue, to explore the nature of quark confinement; dramatic improvements in our understanding of the QCD structure of the hadrons through the extension of our knowledge of their parton distribution functions to high xBjorken, where they are dominated by underlying valence quark structure, and a program of nucleon ''tomography'' via measurements of the Generalized Parton Distributions (GPDs), a broad program of experiments in the physics of nuclei that aims to understand the QCD basis for the nucleon-nucleon force and how nucleons and mesons arise as an approximation to the underlying quark-gluon structure; and precision tests of the Standard Model through parity violating deep inelastic and Moeller scattering. The Upgrade includes: doubling the accelerating voltages of the linacs by adding 10 new high-performance cryomodules; the requisite expansion of the 2K cryogenics plant and rf power systems to support these cryomodules; upgrading the beam transport system from 6 to 12 GeV through extensive re-use and/or modification of existing hardware; and the addition of one recirculation arc, a new experimental area, and the beamline to it; and the construction of major new experimental equipment for the GPD, high-xBjorken, and hybrid meson programs. The presentation will describe the science briefly and provide some details about the accelerator plans

  16. Procurement and commissioning of the CHL refrigerator at CEBAF

    International Nuclear Information System (INIS)

    Chronis, W.C.; Arenius, D.M.; Bevins, B.S.; Ganni, V.; Kashy, D.H.; Keesee, M.M.; Reid, T.R.; Wilson, J.D.

    1996-01-01

    The CEBAF Central Helium Liquefier (CHL) provides 2K refrigeration to the 338 superconducting niobium cavities in two 400 MeV linacs and one 45 MeV injector. The CHL consists of three first stage and three second stage compressors, a 4.5K cold box, a 2K cold box, liquid and gaseous helium storage, liquid nitrogen storage, and transfer lines. Figure 1 presents a block diagram of the CHL refrigerator. The system was designed to provide 4.8 kW of primary refrigeration at 2K, 12 kW of shield refrigeration at 45K for the linac cryomodules, and 10 g/s of liquid flow for the end stations. In April 1994, stable 2K operation of the previously uncommissioned cold compressors was achieved. The cold compressors are a cold vacuum pump with an inlet temperature of circa 3.0K. These compressors operate on magnetic bearing,s and therefore eliminate the possibility of contamination due to any air leaks into the system. Operational data and commissioning experience as they relate to the warm gaseous helium compressors, turbines, instrumentation and control, and the cold compressors are presented

  17. Low mass large aperture vacuum window development at CEBAF

    International Nuclear Information System (INIS)

    Keppel, C.

    1995-01-01

    Large aperture low mass vacuum windows are being developed for the HMS (High Momentum Spectrometer) and SOS (Short Orbit Spectrometer) spectrometers in Hall C at CEBAF. Because multiple scattering degrades the performance of a spectrometer it is important that the volume be evacuated and that the entrance and exit windows be as low mass as possible. The material used for such windows must be thin and light enough so as to have minimum effect of the beam, and at the same time, be thick and strong enough to operate reliably and safely. To achieve these goals, composite vacuum windows have been constructed of a thin sheet of Mylar with a reinforcing fabric. Reinforcing fabrics such as Kevlar and Spectra are available with tensile strengths significantly greater than that of Mylar. A thin layer of Myler remains necessary since the fabrics cannot achieve any sort of vacuum seal. The design, fabrication, testing, and operating experience with such composite windows for the Hall C spectrometers will be discussed

  18. Photoproduction of Scalar Mesons Using the CEBAF Large Acceptance Spectrometer (CLAS)

    Science.gov (United States)

    Chandavar, Shloka K.

    The search for glueballs has been ongoing for several decades. The lightest glueball has been predicted by quenched lattice QCD to have mass in the range of 1.0--1.7 GeV and JPC = 0++ . The mixing of glueball states with neighbouring meson states complicates their identification and hence several experiments have been carried out over the years to study the glueball candidates. By analyzing the decay channels and production mechanisms of these candidates, their glueball content can theoretically be determined. In reality, a lot of confusion still exists about the status of these glueball candidates. The f0(1500) is one of several contenders for the lightest glueball, which has been extensively studied in several different kinds of experiments. However, there exists no photoproduction data on this particle. In the analysis presented in this dissertation, the presence of the f0(1500) in the KS 0KS0 channel is investigated in photoproduction using the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility, also called Jefferson Lab (JLab). This is done by studying the reaction, gammap → fJp → KS0 KS0p → 2(pi +pi-)p using data from the g12 experiment. A clear peak is seen at 1500 MeV in the background subtracted data. This is enhanced if the momentum transfer is restricted to be less than 1 GeV2. Comparing with simulations, it is seen that this peak is associated with t channel production mechanism. The f 2'(1525) has a mass of 1525 MeV and a width of 73 MeV, and hence there is a possibility of it contributing to the peak observed in our data. A moments analysis seems to suggest some presence of a D wave, however, the low acceptance at forward and backward angles prohibits a definitive conclusion.

  19. Conceptual design report of a compton polarimeter for CEBAF hall A

    Energy Technology Data Exchange (ETDEWEB)

    Bardin, G.; Cavata, C.; Neyret, D.; Frois, B.; Jorda, J.P.; Legoff, J.M.; Platchkov, S.; Steinmetz, L.; Juillard, M.; Authier, M.; Mangeot, P.; Rebourgeard, P.; Colombel, N.; Girardot, P.; Martinot, J.; Sellier, J.C.; Veyssiere, C. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. d`Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l`Instrumentation Associee; Berthot, J.; Bertin, P.Y.; Breton, V.; Fonvieille, H.; Roblin, Y. [Institut National de Physique Nucleaire et de Physique des Particules (IN2P3), 75 - Paris (France); Chen, J.P. [Continuous Electron Beam Accelerator Facility, Newport News, VA (United States)

    1996-12-31

    This report describes the design of the Compton polarimeter for the Cebaf electron beam in End Station A. The method of Compton polarimeter is first introduced. It is shown that at CEBAF beam intensities, the use of standard visible LASER light gives too low counting rates. An amplification scheme of the LASER beam based on a high finesse optical cavity is proposed. Expected luminosities with and without such a cavity are given. The polarimeter setup, including a 4 dipole magnet chicane, a photon and an electron detector, is detailed. The various sources of systematic error on the electron beam polarization measurement are discussed. (author). 82 refs.

  20. Exclusive processes: Tests of coherent QCD phenomena and nucleon substructure at CEBAF

    International Nuclear Information System (INIS)

    Brodsky, S.J.

    1994-07-01

    Measurements of exclusive processes such as electroproduction, photoproduction, and Compton scattering are among the most sensitive probes of proton structure and coherent phenomena in quantum chromodynamics. The continuous electron beam at CEBAF, upgraded in laboratory energy to 10--12 GeV, will allow a systematic study of exclusive, semi-inclusive, and inclusive reactions in a kinematic range well-tuned to the study of fundamental nucleon and nuclear substructure. I also discuss the potential at CEBAF for studying novel QCD phenomena at the charm production threshold, including the possible production of nuclear-bound quarkonium

  1. Color transparency after the NE18 and E665 experiments: Outlook and perspectives at CEBAF

    Energy Technology Data Exchange (ETDEWEB)

    Nemchik, J. [Inst. of Experimental Physicals, Kosice (Czechoslovakia); Nikolaev, N.N.; Zakharov, B.G. [L.D. Landau Inst. for Theoretical Physics, Moscow (Russian Federation)

    1994-04-01

    CEBAF is a high-luminocity factory of virtual photons with variable virtuality Q{sup 2} and transverse size. This makes CEBAF, in particular after the energy upgrade to (8-12)GeV, an ideal facility for uncovering new phenomena, and opening new windows, at the interface of the perturbative and nonperturbative QCD. The authors discuss color transparency as the case for a broad program on electroproduction of vector mesons {rho}{sup 0}, {omega}{sup 0}, {phi}{sup 0} and their radial excitations {rho}{prime}, {omega}{prime}, {phi}{prime} at CEBAF. They also comment on the second generation of experiments on color transparency in {sup 4}He(e, e{prime}p) scattering, which are also feasible at CEBAF. In 1994, they can make more reliable projections into future because their understanding of the onset of color transparency has greatly been augmented by two experiments completed in 1993: (i) no effect of CT was seen in the SLAC NE18 experiment on A(e, e{prime}p) scattering at virtualities of the exchanged photon Q{sup 2} {approx_lt} 7 GeV{sup 2}, (ii) strong signal of CT was observed in the FNAL E665 experiment on exclusive {rho}{sup 0}-meson production in deep inelastic scattering in the same range of Q{sup 2}. They discuss the impact of these observations on the CEBAF experimental program. They argue they both are good news, both were anticipated theoretically, and both rule in the correct QCD mechanism of the onset of CT.

  2. FFAGS for muon acceleration

    International Nuclear Information System (INIS)

    Berg, J. Scott; Kahn, Stephen; Palmer, Robert; Trbojevic, Dejan; Johnstone, Carol; Keil, Eberhard; Aiba, Masamitsu; Machida, Shinji; Mori, Yoshiharu; Ogitsu, Toru; Ohmori, Chihiro; Sessler, Andrew; Koscielniak, Shane

    2003-01-01

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

  3. Environmental assessment: Continuous Electron Beam Accelerator Facility, Newport News, Virginia

    International Nuclear Information System (INIS)

    1987-01-01

    This Environmental Assessment has been prepared by the US Department of Energy (DOE) to fulfill its obligations pursuant to Sect. 102 of the National Environmental Policy Act (NEPA) of 1969 (Public Law 91-190). The proposed federal action addressed in this document is DOE's funding of a Continuous Electron Beam Accelerator Facility (CEBAF) at Newport News, Virginia. DOE intends to contract with the Southeastern Universities Research Association (SURA) for operation of CEBAF, a continuous wave (CW) linear accelerator system (linac) capable of providing high-duty-factor beams throughout the energy range from 0.5 to 4.0 GeV. CEBAF will be the first of its kind worldwide and will offer a multi-GeV energy, high-intensity, high-duty-factor electron beam for use by the US nuclear physics community in research on the states of nuclear matter and the short-distance behavior of nuclei. The CEBAF project is largely in the conceptual design stage, with some components in the preliminary design stage. Construction is anticipated to begin in 1987 and be completed by 1992

  4. QMM Project. A proposal for field map measurement of the six HRS Quadrupoles in Hall A, CEBAF

    International Nuclear Information System (INIS)

    Fonvieille, H.; Quemener, G.; Vernin, P.

    1993-12-01

    The proposed measurements of the magnetic field maps of the six HRS quadrupoles in Hall A at CEBAF is summarized. The basis of the measurement using rotating coils and a preliminary design of the apparatus are presented. (author)

  5. A Generalized Correlation Plot Package for the CEBAF Control System

    International Nuclear Information System (INIS)

    D. Wu; W. Akers; S. Schaffner; H. Shoaee; W. A. Watson; D. Wetherholt

    1996-01-01

    The Correlation Package is a general facility for data acquisition and analysis serving as an online environment for performing a wide variety of machine physics experiments and engineering diagnostics. Typical correlation experiments consist of an initial set of actions followed by stepping one or two accelerator parameters while measuring up to several hundred control system parameters. The package utilizes the CDEV [1] device API to access accelerator systems. A variety of analysis and graphics tools are included through integration with the Matlab math modeling package. A post- acquisition script capability is available to automate the data reduction process. A callable interface allows this facility to serve as the data acquisition and analysis engine for high level applications. A planned interface to archived accelerator data will allow the same analysis and graphics tools to be used for viewing and correlating history data. The object oriented design and C++ implementation details as well as the current status of the Correlation Package will be presented

  6. Photoproduction opportunities at CEBAF: Meson spectroscopy and the physics of flying φ's

    International Nuclear Information System (INIS)

    Dzierba, A.R.

    1994-01-01

    The availability of high-intensity photon beams with an efficient duty-factor and with energies in the range 10 to 12 GeV makes possible studies in meson spectroscopy, rare decays and possibly symmetry tests such as CP and CPT. Indeed, with a 6 GeV tagged photon beam, realizable in the near future at CEBAF, measurements of rare radiative decays of the φ's will be made. At higher energies, a photon beam could be used to answer a number of questions in meson spectroscopy. An even more exciting possibility is the use of photon beams to produce an intense source of φ's. The physics contemplated at e + e - φ factories, such as CP and CPT tests, might be also studied at CEBAF with completely different and complementary systematics; e.g. having the φ's decay in flight may offer distinct advantages over φ's produced at rest

  7. Nucleon resonance electroproduction at high momentum transers: Results from SLAC and suggestions for CEBAF

    Energy Technology Data Exchange (ETDEWEB)

    Keppel, C. [Virginia Union Univ., Richmond, VA (United States)

    1994-04-01

    Nucleon resonance electroproduction results from SLAC Experiment E14OX are presented. A CEBAF facility with doubled energy would enable similar high momentum transfer measurements to be made with greater accuracy. Of particular interest are the Delta P{sub 33}(1232) resonance form factor and R = {sigma}{sub L}/{sigma}{sub T}, the ratio of the longitudinal and transverse components of the cross section. A suggestion is made to study these quantities in conjunction with Bloom-Gilman duality.

  8. Change in operating parameters of the Continuous Electron Beam Accelerator Facility and Free Electron Laser, Thomas Jefferson National Accelerator Facility, Newport News, Virginia

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-10-01

    In this environmental assessment (EA), the US Department of Energy (DOE) reports the results of an analysis of the potential environmental impacts from a proposed change in operating parameters of the Continuous Electron Beam Accelerator Facility (CEBAF), and operation of the Free Electron Laser (FEL) facility beyond the initial demonstration period. With this proposal, DOE intends to increase CEBAF operating range from its current operating maximum beam energy of 4.0 GeV [giga-(billion) electron volts] to 8.0 GeV at a beam power of no greater than 1,000 kW [1 megawatt (MW)], its maximum attainable level, based on current technology and knowledge, without significant, costly equipment modifications. DOE has prepared an EA for this action to determine the potential for adverse impacts from operation of CEBAF and the FEL at the proposed levels. Changing the operating parameters of CEBAF would require no new major construction and minor modifications to the accelerator, its support systems, the FEL, and onsite utility systems. Modifications and performance improvements would be made to (1) the accelerator housed in the underground tunnels, (2) its support systems located in the above ground service buildings, and (3) the water and equipment cooling systems both in the tunnel and at the ground surface. All work would be performed on previously disturbed land and in, on, or adjacent to existing buildings, structures, and equipment. With the proposed action, the recently constructed FEL facility at the Jefferson Lab would operate in concert with CEBAF beyond its demonstration period and up to its maximum effective electron beam power level of 210 kW. In this EA, DOE evaluates the impacts of the no-action alternative and the proposed action alternative. Alternatives considered, but dismissed from further evaluation, were the use of another accelerator facility and the use of another technology.

  9. Change in operating parameters of the Continuous Electron Beam Accelerator Facility and Free Electron Laser, Thomas Jefferson National Accelerator Facility, Newport News, Virginia

    International Nuclear Information System (INIS)

    1997-10-01

    In this environmental assessment (EA), the US Department of Energy (DOE) reports the results of an analysis of the potential environmental impacts from a proposed change in operating parameters of the Continuous Electron Beam Accelerator Facility (CEBAF), and operation of the Free Electron Laser (FEL) facility beyond the initial demonstration period. With this proposal, DOE intends to increase CEBAF operating range from its current operating maximum beam energy of 4.0 GeV [giga-(billion) electron volts] to 8.0 GeV at a beam power of no greater than 1,000 kW [1 megawatt (MW)], its maximum attainable level, based on current technology and knowledge, without significant, costly equipment modifications. DOE has prepared an EA for this action to determine the potential for adverse impacts from operation of CEBAF and the FEL at the proposed levels. Changing the operating parameters of CEBAF would require no new major construction and minor modifications to the accelerator, its support systems, the FEL, and onsite utility systems. Modifications and performance improvements would be made to (1) the accelerator housed in the underground tunnels, (2) its support systems located in the above ground service buildings, and (3) the water and equipment cooling systems both in the tunnel and at the ground surface. All work would be performed on previously disturbed land and in, on, or adjacent to existing buildings, structures, and equipment. With the proposed action, the recently constructed FEL facility at the Jefferson Lab would operate in concert with CEBAF beyond its demonstration period and up to its maximum effective electron beam power level of 210 kW. In this EA, DOE evaluates the impacts of the no-action alternative and the proposed action alternative. Alternatives considered, but dismissed from further evaluation, were the use of another accelerator facility and the use of another technology

  10. The continuous electron beam accelerator facility

    International Nuclear Information System (INIS)

    Grunder, H.A.

    1989-01-01

    Tunnel construction and accelerator component development, assembly, and testing are under way at the Continuous Electron Beam Accelerator Facility. CEBAF's 4-GeV, 200-μA superconducting recirculating accelerator will provide cw beam to simultaneous experiments in three end stations for studies of the nuclear many-body system, its quark substructure, and the strong and electroweak interactions governing this form of matter. Prototype accelerating cavities, assembled in cryostats and tested on site, continue to exceed performance specifications. An on-site liquid helium capability supports cryostat development and cavity testing. Major elements of the accelerator instrumentation and control hardware and software are in use in cryogenics, rf, and injector tests. Prototype rf systems have been operated and prototype klystrons have been ordered. The initial, 100-keV, room-temperature region of the 45-MeV injector is operational and meets specifications. CEBAF's end stations have been conceptually designed; experimental equipment conceptual designs will be completed in 1989. 2 refs., 5 figs., 2 tabs

  11. Diffractive electroproduction of s{bar s} mesons off nuclei at CEBAF energies

    Energy Technology Data Exchange (ETDEWEB)

    Benhar, O. [Instituto Superiore di Sanita, Roma (Italy); Nikolaev, N.N.; Zakharov, B.G. [L.D. Landau Inst. for Theoretical Physics, Juelich (Germany)] [and others

    1994-04-01

    The authors discuss diffractive incoherent electroproduction of s{bar s} mesons off nuclear targets at beam energies that are expected to be available at CEBAF (5-8 GeV). The Q{sup 2} and target mass dependence of the {phi} and {phi}{prime} transparency ratios has been studied within a theoretical approach in which the propagation of the s{bar s} pair through the nuclear medium is described in terms of the quantum mechanical evolution operator. The authors predict a complex pattern of nuclear effects, whose experimental study may provide information on several issues relevant to the understanding of QCD, both in the perturbative and nonperturbative regimes.

  12. Superharp: A wire scanner with absolute position readout for beam energy measurement at CEBAF

    International Nuclear Information System (INIS)

    Yan, C.

    1994-01-01

    Superharp is an upgrade CEBAF wire scanner with absolute position readout from shaft encoder. As high precision absolute beam position probe (Δx ∼ 10μm), three pairs of superharps are installed at the entrance, the mid-point, and the exit of Hall C arc beamline in beam switch yard, which will be tuned in dispersive mode as energy spectrometer performing 10 -3 beam energy measurement. With dual sensor system: the direct current pickup and the bremsstrahlung detection electronics, beam profile can be obtained by superharp at wide beam current range from 1 μA to 100 μA

  13. Development and Testing of a Prototype Tuner for the CEBAF Upgrade Cryomodule

    International Nuclear Information System (INIS)

    G. Davis; J. Delayen; M. Drury; E. Feldl

    2001-01-01

    An upgrade cryomodule is being developed for CEBAF at Jefferson Lab. The high-gradient, low-current operation of the superconducting cavities puts stringent requirements on the accuracy of the frequency tuner: a resolution of 1 Hz over a range of 400 KHz. We have developed and tested such a tuner; it consists of a stepper-motor-driven coarse tuner, operating in parallel with a piezo-actuator-driven fine tuner. Tuner test procedures and results are summarized, including frequency resolution, range, and linearity (i.e. frequency vs. tuner position), as well as microphonic effects resulting from tuner operation

  14. Design of a large 2.0 k refrigerator for CEBAF

    International Nuclear Information System (INIS)

    Parish, H.; Hood, C.; Kreinbrink, K.; Appleton, W.; Gistau, G.

    1991-01-01

    The CEBAF refrigerator is designed to produce 4,620 watts of refrigeration at 2.0 K, another 180 watts at 2.14 K plus 4.5 K liquid and higher temperature cooling for shields. Several design features are described, including a modular concept for the 2 K and 4.5 K refrigerator sections and the use of multistage centrifugal cryogenic compressors to achieve the 2 K. The development program for the centrifugal cryogenic compressors is discussed. Some startup information is also provided

  15. SRF Performance of CEBAF After Thermal Cycle to Ambient Temperature

    CERN Document Server

    Rimmer, Robert; Preble, Joseph P; Reece, Charles E

    2005-01-01

    In September 2003, in the wake of Hurricane Isabel, JLab was without power for four days after a tree fell on the main power lines feeding the site. This was long enough to lose insulating vacuum in the cryomodules and cryogenic systems resulting in the whole accelerator warming up and the total loss of the liquid helium inventory. This thermal cycle stressed many of the cryomodule components causing several cavities to become inoperable due to helium to vacuum leaks. At the same time the thermal cycle released years of adsorbed gas from the cold surfaces. Over the next days and weeks this gas was pumped away, the insulating vacuum was restored and the machine was cooled back down and re-commissioned. In a testament to the robustness of SRF technology, only a small loss in energy capability was apparent, although individual cavities had quite different field-emission characteristics compared to before the event. In Summer 2004 a section of the machine was again cycled to room temperature during the long maint...

  16. SRF Performance of CEBAF After Thermal Cycle to Ambient Temperature

    International Nuclear Information System (INIS)

    Robert Rimmer; Jay Benesch; Joseph Preble; Charles Reece

    2005-01-01

    In September 2003, in the wake of Hurricane Isabel, JLab was without power for four days after a tree fell on the main power lines feeding the site. This was long enough to lose insulating vacuum in the cryomodules and cryogenic systems resulting in the whole accelerator warming up and the total loss of the liquid helium inventory. This thermal cycle stressed many of the cryomodule components causing several cavities to become inoperable due to helium to vacuum leaks. At the same time the thermal cycle released years of adsorbed gas from the cold surfaces. Over the next days and weeks this gas was pumped away, the insulating vacuum was restored and the machine was cooled back down and re-commissioned. In a testament to the robustness of SRF technology, only a small loss in energy capability was apparent, although individual cavities had quite different field-emission characteristics compared to before the event. In Summer 2004 a section of the machine was again cycled to room temperature during the long maintenance shutdown. We report on the overall SRF performance of the machine after these major disturbances and on efforts to characterize and optimize the new behavior for high-energy running

  17. Status of Thomas Jefferson National Accelerator Facility (Jefferson Lab)

    International Nuclear Information System (INIS)

    H.A. Grunder

    1997-01-01

    When first beam was delivered on target in July 1994, the Continuous Electron Beam Accelerator Facility (CEBAF), in Newport News, Virginia realized the return on years of planning and work to create a laboratory devoted to exploration of matter that interacts through the strong force, which holds the quarks inside the proton and binds protons and neutrons into the nucleus. Dedicated this year as the Thomas Jefferson National Accelerator Facility (Jefferson Lab), the completion of construction and beginning of its experimental program has culminated a process that began more than a decade ago with the convening of the Bromley Panel to look at research possibilities for such an electron accelerator

  18. Photoproduction opportunities at CEBAF: Meson spectroscopy and the physics of flying {phi}`s

    Energy Technology Data Exchange (ETDEWEB)

    Dzierba, A.R. [Indiana Univ., Bloomington, IN (United States)

    1994-04-01

    The availability of high-intensity photon beams with an efficient duty-factor and with energies in the range 10 to 12 GeV makes possible studies in meson spectroscopy, rare decays and possibly symmetry tests such as CP and CPT. Indeed, with a 6 GeV tagged photon beam, realizable in the near future at CEBAF, measurements of rare radiative decays of the {phi}`s will be made. At higher energies, a photon beam could be used to answer a number of questions in meson spectroscopy. An even more exciting possibility is the use of photon beams to produce an intense source of {phi}`s. The physics contemplated at e{sup +}e{sup {minus}} {phi} factories, such as CP and CPT tests, might be also studied at CEBAF with completely different and complementary systematics; e.g. having the {phi}`s decay in flight may offer distinct advantages over {phi}`s produced at rest.

  19. A content addressable memory for use in CEBAF's CLAS detector level 2 triggering system

    International Nuclear Information System (INIS)

    Hodson, R.F.; Doughty, D.C. Jr.; Allgood, D.C.; Campbell, S.A.; Wilson, W.C.; Bickley, M.H.

    1996-01-01

    A collaboration of researchers from CEBAF, CNU and NASA is designing a 256-32 specialized Content Addressable Memory (CAM) for the level 2 triggering system in CEBAF's CLAS detector. These integrated circuits will find tracks and the momentum and angle of each track within 2 microseconds of an event. The custom CAM can operate as conventional memory, performing read and write operations, and can additionally perform independent byte compare operations across all words simultaneously. It is this compare feature which makes these CAMs attractive for identifying tracks passing through drift chambers by linking together segment number triplets within the CAM. Simulations have indicated that less than 16 k triplets need to be stored for each sector of the detector. This implies the level 2 triggering can be performed with 64 CAM chips per sector, or 384 total. Each data channel into a sector CAM array is buffered in a FIFO and is designed to handle aggregate data rates up to 750 Mbs for three channels (one channel/superlayer). The architecture of the level 2 trigger and details of the CAM chip design are discussed along with a performance report on our prototype CAMs

  20. Hurricane Isabel gives accelerators a severe test

    International Nuclear Information System (INIS)

    Swapan Chattopadhyay

    2004-01-01

    Hurricane Isabel was at category five--the most violent on the Saffir-Simpson scale of hurricane strength--when it began threatening the central Atlantic seaboard of the US. Over the course of several days, precautions against the extreme weather conditions were taken across the Jefferson Lab site in south-east Virginia. On 18 September 2003, when Isabel struck North Carolina's Outer Banks and moved northward, directly across the region around the laboratory, the storm was still quite destructive, albeit considerably reduced in strength. The flood surge and trees felled by wind substantially damaged or even devastated buildings and homes, including many belonging to Jefferson Lab staff members. For the laboratory itself, Isabel delivered an unplanned and severe challenge in another form: a power outage that lasted nearly three-and-a-half days, and which severely tested the robustness of Jefferson Lab's two superconducting machines, the Continuous Electron Beam Accelerator Facility (CEBAF) and the superconducting radiofrequency ''driver'' accelerator of the laboratory's free-electron laser. Robustness matters greatly for science at a time when microwave superconducting linear accelerators (linacs) are not only being considered, but in some cases already being built for projects such as neutron sources, rare-isotope accelerators, innovative light sources and TeV-scale electron-positron linear colliders. Hurricane Isabel interrupted a several-week-long maintenance shutdown of CEBAF, which serves nuclear and particle physics and represents the world's pioneering large-scale implementation of superconducting radiofrequency (SRF) technology. The racetrack-shaped machine is actually a pair of 500-600 MeV SRF linacs interconnected by recirculation arc beamlines. CEBAF delivers simultaneous beams at up to 6 GeV to three experimental halls. An imminent upgrade will double the energy to 12 GeV and add an extra hall for ''quark confinement'' studies. On a smaller scale

  1. Operational optimization of large-scale SRF accelerators

    International Nuclear Information System (INIS)

    J. R. Delayen; L. R. Doolittle; C. E. Reece

    1999-01-01

    Unlike other types of accelerator subsystems, because of the flexibility in setting the gradient in each cavity, an SRF linac has many operational degrees of freedom. The overall linac has an operational envelope (beam voltage and current) that depends on acceptable reliability, cryogenic capacity, and RF power budget. For economic and end-user physics reasons, one typically wants to run as close to the edge of the operational envelope as possible. With about 160 cavities in each of the CEBAF linacs. The authors have been forced to treat this problem in a very general way, and satisfy other non-fundamental needs as energy lock and rapid recovery from failures. They present a description of the relevant diverse constraints and the solution developed for CEBAF

  2. An RF input coupler system for the CEBAF energy upgrade cryomodule

    International Nuclear Information System (INIS)

    J.R. Delayen; L.R. Doolittle; T. Hiatt; J. Hogan; J. Mammosser; L. Phillips; J. Preble; W.J. Schneider; G. Wu

    1999-01-01

    Long term plans for CEBAF at Jefferson Lab call for achieving 12 GeV in the middle of the next decade and 24 GeV after 2010. Thus an upgraded cryomodule to more than double the present voltage is under development. A new waveguide coupler system has been designed and prototypes are currently being developed. This coupler, unlike the original, has a nominal Q ext of 2.1 x 10 7 , reduced sensitivity of Q ext to mechanical deformation, reduced field asymmetry within the beam envelope, freedom from window arcing with a single window at 300 K, and is capable of transmitting 6kW CW both traveling wave and in full reflection

  3. Issues in light meson spectroscopy: The case for meson spectroscopy at CEBAF

    Energy Technology Data Exchange (ETDEWEB)

    Godfrey, S. [Carleton Univ., Ottawa (Canada)

    1994-04-01

    The author reviews some outstanding issues in meson spectroscopy. The most important qualitative issue is whether hadrons with explicit gluonic degrees of freedom exist. To answer this question requires a much better understanding of conventional q{bar q} mesons. The author therefore begins by examining the status of conventional meson spectroscopy and how the situation can be improved. The expected properties of gluonic excitations are discussed with particular emphasis on hybrids to give guidance to experimental searches. Multiquark systems are commented upon as they are likely to be important in the mass region under study and will have to be understood better. In the final section the author discusses the opportunities that CEBAF can offer for the study of meson spectroscopy.

  4. Excited baryon form-factors at high momentum transfer at CEBAF at higher energies

    Energy Technology Data Exchange (ETDEWEB)

    Stoler, P. [Rensselaer Polytechnic Inst., Troy, NY (United States)

    1994-04-01

    The possibilities of measuring the properties of excited nucleons at high Q{sup 2} by means of exclusive single meson production at CEBAF with an electron energy of 8 GeV is considered. The motivation is to access short range phenomena in baryon structure, and to investigate the transition from the low Q{sup 2} non-perturbative QCD regime, where constituent quark models are valid, to higher Q{sup 2} where it is believed perturbative QCD plays an increasingly important role. It is found that high quality baryon decay angular distributions can be obtained for the most prominent states up to Q{sup 2} {approximately} 12 GeV{sup 2}/c{sup 2} using a set of moderate resolution, large solid angle magnetic spectrometers.

  5. Fabrication and Testing of the SRF Cavities for the CEBAF 12 GeV Upgrade Prototype Cryomodule Renascence

    International Nuclear Information System (INIS)

    Charles Reece; Edward Daly; Stephen Manning; Robert Manus; Samuel Morgan; Joseph Ozelis; Larry Turlington

    2005-01-01

    Twelve seven-cell niobium cavities for the CEBAF 12 GeV upgrade prototype cryomodule Renascence have been fabricated at JLab and tested individually. This set includes four of the ''Low Loss'' (LL) design and eight of the ''High Gradient'' (HG) design. The fabrication strategy was an efficient mix of batch job-shop component machining and in-house EBW, chemistry, and final-step machining to meet mechanical tolerances. Process highlights will be presented. The cavities have been tested at 2.07 K, the intended CEBAF operating temperature. Performance exceeded the tentative design requirement of 19.2 MV/m cw with less than 29 W dynamic heat dissipation. These results, as well as the HOM damping performance will be presented

  6. Fabrication and Testing of the SRF cavities for the CEBAF 12 GeV Upgrade Prototype Cryomodule Renascence

    International Nuclear Information System (INIS)

    C. E. Reece; E. F. Daly; S. Manning; R. Manus; S. Morgan; J. P. Ozelis; L. Turlington

    2005-01-01

    Twelve seven-cell niobium cavities for the CEBAF 12 GeV upgrade prototype cryomodule Renascence have been fabricated at JLab and tested individually. This set includes four of the ''Low Loss'' (LL) design and eight of the ''High Gradient'' (HG) design. The fabrication strategy was an efficient mix of batch job-shop component machining and in-house EBW, chemistry, and final-step machining to meet mechanical tolerances. Process highlights will be presented. The cavities have been tested at 2.07 K, the intended CEBAF operating temperature. Performance exceeded the tentative design requirement of 19.2 MV/m CW with less than 29 W dynamic heat dissipation. These results, as well as the HOM damping performance are presented

  7. Color coherent effects in (e,e{prime}N) and (e,e{prime}N,N(h)) processes at CEBAF

    Energy Technology Data Exchange (ETDEWEB)

    Frankfurt, L.L.; Sargsyan, M.M. [Tel Aviv Univ. (Israel); Strikman, M.I. [Pennsylvania State Univ., University Park, PA (United States)]|[St. Petersburg Nuclear Physics Inst. (Russian Federation)

    1994-04-01

    The options for investigating color coherent effects and competing nuclear effects of nucleon-nucleon correlations in nuclei, nuclear shell effects in (e, e{prime}N) and (e, e{prime}NN(h)) reactions are considered. They argue that extension of CEBAF energies to reach Q{sup 2} = 10 GeV{sup 2} will allow systematical investigations of color coherent effects in nonperturbative regime of QCD and their interplay with nuclear effects.

  8. Color coherent effects in (e,e'N) and (e,e'N,N(h)) processes at CEBAF

    International Nuclear Information System (INIS)

    Frankfurt, L.L.; Sargsyan, M.M.; Strikman, M.I.

    1994-01-01

    The options for investigating color coherent effects and competing nuclear effects of nucleon-nucleon correlations in nuclei, nuclear shell effects in (e, e'N) and (e, e'NN(h)) reactions are considered. They argue that extension of CEBAF energies to reach Q 2 = 10 GeV 2 will allow systematical investigations of color coherent effects in nonperturbative regime of QCD and their interplay with nuclear effects

  9. Applications of the second-order achromat concept to the design of particle accelerators

    International Nuclear Information System (INIS)

    Brown, K.L.; Servranckx, R.V.

    1985-05-01

    A property of the second-order achromat, whereby dipole and sextupole families may be inserted into a lattice for chromatic corrections without introducing second-order geometrical (on momentum) optical distortions, has been incorporated in several new particle accelerator designs. These include the SLC at SLAC, LEP at CERN, the EROS pulse stretcher ring at Saskatoon, the CEBAF ring at SURA, and the MIT ring

  10. Economic and education impact of building the Continuous Electron Beam Accelerator Facility

    International Nuclear Information System (INIS)

    Hartline, B.

    1996-01-01

    The Continuous Electron Beam Accelerator Facility (CEBAF) was built in Newport News, Virginia, between 1987 and 1995 and is a new basic research laboratory christened the Thomas Jefferson National Accelerator Facility (Jefferson Lab). Jefferson Lab's science and technology mission has major economic and educational benefits: basic research discoveries, improvement and application of key technologies associated with the accelerator and the experiments, extensive subcontracting with industry, and diverse employment and educational opportunities. The $600 million invested by federal, state, local and international partners to build Jefferson Lab has had substantial economic and educational benefits locally, as well as significant benefits distributed among industries and universities throughout the United States

  11. Anomalous Q(sub 0) Results in the CEBAF South Linac

    International Nuclear Information System (INIS)

    William J. Schneider; M. Drury; Joe Preble

    1993-01-01

    While in practice, the performance of cavities - Q(sub 0) versus E(sub acc) - in the assembled CEBAF cryomodule corresponds in nearly every respect to the performance as measured in the vertical test area; there are a few cases where this is not true. On six (6) of the twenty (20) cryomodules installed in the south linac, cavity 4 specifically, and one other cavity in cryomodule 7 have an anomalous low Q(sub 0). Investigation into the source of the low Q(sub 0) on these particular cavities have centered around trapped magnetic fields, slow cooldowns or maldistribution of He flow during cooldown leading to hydride precipitation and Q(sub 0) disease. Other possibilities such as low window Q(sub 0)'s or harmonic content of the klystron were also considered. A detailed investigation to understand the phenomena leading to the low Q(sub 0)'s on cryomodule 7 and 8 is discussed. We have found evidence suggesting cooldown dependent Q(sub 0) disease as well as window heating to account for some of the discrepancies but not all. A complete explanation of the problem is still under further investigation

  12. New challenges for HEP computing: RHIC [Relativistic Heavy Ion Collider] and CEBAF [Continuous Electron Beam Accelerator Facility

    International Nuclear Information System (INIS)

    LeVine, M.J.

    1990-01-01

    We will look at two facilities; RHIC and CEBF. CEBF is in the construction phase, RHIC is about to begin construction. For each of them, we examine the kinds of physics measurements that motivated their construction, and the implications of these experiments for computing. Emphasis will be on on-line requirements, driven by the data rates produced by these experiments

  13. First e⁻/γ Commissioning Results for the GlueX Experiment/Hall D at CEBAF

    Energy Technology Data Exchange (ETDEWEB)

    McCaughan, Michael D. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Satogata, Todd J. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Roblin, Yves R. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Benesch, Jay F. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    2015-09-01

    Experimental Hall D, with flagship experiment GlueX, was constructed as part of the 12 GeV CEBAF upgrade. A new magnetically extracted electron beam line was installed to support this hall. Bremsstrahlung photons from retractable radiators are delivered to the experiment through a series of collimators following a long drift to allow for beam convergence. Coherent Bremsstrahlung generated by interaction with a diamond radiator will achieve a nominal 40% linear polarization and photon energies between 8.5 and 9 GeV from 12.1 GeV electrons, which are then tagged or diverted to a medium power 60kW electron dump. The expected photon flux is 107-108 Hz. This paper discusses the experimental line design, commissioning experience gained since first beam in spring 2014, and the present results of beam commissioning by the experiment.

  14. Proceeding of the 11th meeting on linear accelerators

    International Nuclear Information System (INIS)

    Nakahara, Kazuo; Anami, Shozo; Takasaki, Eiichi

    1986-08-01

    The study group on linear accelerators has attained the period of 10 years. The worldwide change of social structure and economical condition during this period affected also linear accelerators. For a while, the new installation of linear accelerators was limited to Japan and China, and the state of standstill continued in Europe and America. Therefore, the large scale projects of electron-positron collision type accelerators started, and LEP of CERN and HERA of DESY in Europe and Linear Collider of SLAC in USA compete the lead together with TRISTAN in Japan. Large electron rings have become the type connecting CW linear accelerators with electromagnets in circular form unlike the conventional type. The developed type of superconducting CW linacs such as CEBAF in USA is planned. In the large accelerators hereafter of CW or pulse type, the RF system of high accuracy and large power output is the key to the success of projects, instead of individual accelerating spaces, high frequency sources, waveguides or controls. When the scale of projects exceeds a certain limit, those cannot be dealt with merely by the experience and means in the past. In this book, the gists of 62 presented papers and invited lectures are collected. (Kako, I.)

  15. Can Accelerators Accelerate Learning?

    International Nuclear Information System (INIS)

    Santos, A. C. F.; Fonseca, P.; Coelho, L. F. S.

    2009-01-01

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

  16. Can Accelerators Accelerate Learning?

    Science.gov (United States)

    Santos, A. C. F.; Fonseca, P.; Coelho, L. F. S.

    2009-03-01

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

  17. Plasma accelerators

    International Nuclear Information System (INIS)

    Bingham, R.; Angelis, U. de; Johnston, T.W.

    1991-01-01

    Recently attention has focused on charged particle acceleration in a plasma by a fast, large amplitude, longitudinal electron plasma wave. The plasma beat wave and plasma wakefield accelerators are two efficient ways of producing ultra-high accelerating gradients. Starting with the plasma beat wave accelerator (PBWA) and laser wakefield accelerator (LWFA) schemes and the plasma wakefield accelerator (PWFA) steady progress has been made in theory, simulations and experiments. Computations are presented for the study of LWFA. (author)

  18. Linear Accelerators

    International Nuclear Information System (INIS)

    Vretenar, M

    2014-01-01

    The main features of radio-frequency linear accelerators are introduced, reviewing the different types of accelerating structures and presenting the main characteristics aspects of linac beam dynamics

  19. Impacts of Continuous Electron Beam Accelerator Facility operations on groundwater and surface water: Appendix 9

    International Nuclear Information System (INIS)

    Lee, D.W.

    1986-04-01

    The operation of the proposed Continuous Electron Beam Accelerator Facility (CEBAF) at Newport News, Virginia, is expected to result in the activation and subsequent contamination of water resources in the vicinity of the accelerator. Since the proposed site is located in the headwaters of the watershed supplying Big Bethel Reservoir, concern has been expressed about possible contamination of water resources used for consumption. Data characterizing the surface water and groundwater regime in the site area are limited. A preliminary geotechnical investigation of the site has been completed (LAW 1985). This investigation concluded that groundwater flow is generally towards the southeast at an estimated velocity of 2.5 m/y. This conclusion is based on groundwater and soil boring data and is very preliminary in nature. This analysis makes use of the data and conclusions developed during the preliminary geotechnical investigation to provide an upper-bound assessment of radioactive contamination from CEBAF operations. A site water balance was prepared to describe the behavior of the hydrologic environment that is in close agreement with the observed data. The transport of contamination in the groundwater regime is assessed using a one-dimensional model. The groundwater model includes the mechanisms of groundwater flow, groundwater recharge, radioactive decay, and groundwater activation. The model formulation results in a closed-form, exact, analytic solution of the concentration of contamination in the groundwater. The groundwater solution is used to provide a source term for a surface-water analysis. The surface-water and groundwater models are prepared for steady state conditions such that they represent conservative evaluations of CEBAF operations

  20. Study of Arc-Related RF Faults in the CEBAF Cryomodules

    Energy Technology Data Exchange (ETDEWEB)

    Douglas Curry; Ganapati Myneni; Ganapati Rao Myneni; John Musson; Thomas Powers; Timothy Whitlatch; Isidoro Campisi; Haipeng Wang

    2004-07-01

    A series of measurements has been conducted on two superconducting radio-frequency (RF) cavity pairs, installed in cryomodules and routinely operated in the Continuous Electron Beam Accelerator Facility, in order to study the RF-vacuum interaction during an RF fault. These arc-related fault rates increase with increasing machine energy, contribute to system downtime, and directly affect the accelerator's availability. For this study, the fundamental power coupler waveguides have been instrumented with vacuum gauges, additional arc detectors, additional infrared sensors, and temperature sensors in order to measure the system response during both steady-state operations and RF fault conditions. Residual gas analyzers have been installed on the waveguide vacuum manifolds to monitor the gas species present during cooldown, RF processing, and operation. Measurements of the signals are presented, a comparison with analysis is shown and results are discussed. The goal of this study is to characterize the RF-vacuum interaction during normal operations. With a better understanding of the installed system response, methods for reducing the fault rate may be devised, ultimately leading to improvements in availability.

  1. Accelerator Service

    International Nuclear Information System (INIS)

    Champelovier, Y.; Ferrari, M.; Gardon, A.; Hadinger, G.; Martin, J.; Plantier, A.

    1998-01-01

    Since the cessation of the operation of hydrogen cluster accelerator in July 1996, four electrostatic accelerators were in operation and used by the peri-nuclear teams working in multidisciplinary collaborations. These are the 4 MV Van de Graaff accelerator, 2,5 MV Van de Graaff accelerator, 400 kV ion implanter as well as the 120 kV isotope separator

  2. Selected topics in particle accelerators: Proceedings of the CAP meetings. Volume 4

    International Nuclear Information System (INIS)

    Parsa, Z.

    1995-01-01

    This Report includes copies of transparencies and notes from the presentations made at the Center for Accelerator Physics at Brookhaven National Laboratory. Editing and changes to the authors' contributions in this Report were made only to fulfill the publication requirements. This volume includes notes and transparencies on eight presentations: ''Application of Accelerator-Driven Spallation Targets - Including Tritium Production and Nuclear Waste Transmutation'', ''BNL 5 MW Pulsed Spallation Neutron Source Study'', ''Designing and Understanding of Magnets with the Help of Conformal Mapping'', ''Laser - Electron Beam Scattering Coherent Compton X-Ray Sources'', ''The LHC Project'', ''Optimization of the Photocathode-Linac Separation for the ATF [Accelerator Test Facility] Injection System'', ''On CEBAF Commissioning: First Results'', and ''The Proposed Booster Application Facility at BNL''. An Appendix lists dates, topics, and speakers from October 1989 to December 1994

  3. Future accelerators (?)

    Energy Technology Data Exchange (ETDEWEB)

    John Womersley

    2003-08-21

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

  4. The CEBAF test package: A symbolic and dynamic test, histogram and parameter package for on- and off-line particle physics data analysis

    International Nuclear Information System (INIS)

    Wood, S.A.; Abbott, S.

    1995-01-01

    Nuclear physics data analysis programs often use packages, such as Q, that allow parameter values, test definitions and histogram booking parameters to be controlled at run time through external files or shared memory. Data within a physics analyzer are usually referenced by indices, leading to a high use of equivalence statements and to extra bookkeeping. In the CEBAF Test Package (CTP), parameters, tests and histogram definitions defined in external files all refer to data elements by the same variable names as used in the C or Fortran source code for the analyzer. This is accomplished by requirieng the analyzer developer to open-quotes registerclose quotes each variable and array that is to be accessible by the package. Any registered variable as well as the test and histogram definitions may be dynamically read and modified by tasks that communicate via standard networking calls. As this package is implemented in C and requires only HBOOK and SUN RPC networking, it is highly portable. CTP works with the CEBAF Online Data Acquisition system (CODA), but may be used with other data acquisition systems or stand alone

  5. Electrostatic accelerators

    OpenAIRE

    Hinterberger, F

    2006-01-01

    The principle of electrostatic accelerators is presented. We consider Cockcroft– Walton, Van de Graaff and Tandem Van de Graaff accelerators. We resume high voltage generators such as cascade generators, Van de Graaff band generators, Pelletron generators, Laddertron generators and Dynamitron generators. The speci c features of accelerating tubes, ion optics and methods of voltage stabilization are described. We discuss the characteristic beam properties and the variety of possible beams. We ...

  6. Electrostatic accelerators

    CERN Document Server

    Hinterberger, F

    2006-01-01

    The principle of electrostatic accelerators is presented. We consider Cockcroft– Walton, Van de Graaff and Tandem Van de Graaff accelerators. We resume high voltage generators such as cascade generators, Van de Graaff band generators, Pelletron generators, Laddertron generators and Dynamitron generators. The speci c features of accelerating tubes, ion optics and methods of voltage stabilization are described. We discuss the characteristic beam properties and the variety of possible beams. We sketch possible applications and the progress in the development of electrostatic accelerators.

  7. Accelerator development

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    Because the use of accelerated heavy ions would provide many opportunities for new and important studies in nuclear physics and nuclear chemistry, as well as other disciplines, both the Chemistry and Physics Divisions are supporting the development of a heavy-ion accelerator. The design of greatest current interest includes a tandem accelerator with a terminal voltage of approximately 25 MV injecting into a linear accelerator with rf superconducting resonators. This combined accelerator facility would be capable of accelerating ions of masses ranging over the entire periodic table to an energy corresponding to approximately 10 MeV/nucleon. This approach, as compared to other concepts, has the advantages of lower construction costs, lower operating power, 100 percent duty factor, and high beam quality (good energy resolution, good timing resolution, small beam size, and small beam divergence). The included sections describe the concept of the proposed heavy-ion accelerator, and the development program aiming at: (1) investigation of the individual questions concerning the superconducting accelerating resonators; (2) construction and testing of prototype accelerator systems; and (3) search for economical solutions to engineering problems. (U.S.)

  8. The Continuous Electron Beam Accelerator Facility: Project status and physics outlook

    International Nuclear Information System (INIS)

    Grunder, H.A.

    1989-01-01

    Nuclear physics research program planning, accelerator tunnel construction, and accelerator component development, assembly, and testing are under way at the Continuous Electron Beam Accelerator Facility, Newport News, Virginia. CEBAF's 4-GeV, 200-μA superconducting recirculating accelerator will provide cw beam to simultaneous experiments in three end stations for studies of the nuclear many-body system, its quark substructure, and the strong and electroweak interactions governing this form of matter. An experimental program is being defined in collaboration with the user community. The experimental halls have been designed, and preliminary experimental equipment conceptual designs have been prepared. Planned for Hall A are two 4-GeV/c high-resolution (δp/p ≤ 10 -4 ) spectrometers (HRS) with moderate acceptance (∼8 msr) for a program of completely exclusive experiments in which the nuclear final state has to be fully specified. A CEBAF large acceptance spectrometer (CLAS) is planned for the program of Hall B, which will include bias-free investigation of hadronic final states in inelastic electron scattering and detection of multiple-particle final states. The CLAS will be a multi-gap device based on a toroidal magnet with six superconducting coils arranged around the beamline to produce an essentially circular magnetic field. Hall C is envisioned as serving a diversity of interests, including form factor measurements, parity violation investigations, form factors of nucleon resonances, and a high-Q 2 baryon resonance program. A moderate-resolution, high-momentum, 6-GeV/c spectrometer (HMS) together with several specialized second arms -- in particular, a symmetric toroidal array spectrometer -- are being planned to carry out Hall C experimentation. 14 figs., 8 tabs

  9. RECIRCULATING ACCELERATION

    International Nuclear Information System (INIS)

    BERG, J.S.; GARREN, A.A.; JOHNSTONE, C.

    2000-01-01

    This paper compares various types of recirculating accelerators, outlining the advantages and disadvantages of various approaches. The accelerators are characterized according to the types of arcs they use: whether there is a single arc for the entire recirculator or there are multiple arcs, and whether the arc(s) are isochronous or non-isochronous

  10. LIBO accelerates

    CERN Multimedia

    2002-01-01

    The prototype module of LIBO, a linear accelerator project designed for cancer therapy, has passed its first proton-beam acceleration test. In parallel a new version - LIBO-30 - is being developed, which promises to open up even more interesting avenues.

  11. Accelerating Inspire

    CERN Document Server

    AUTHOR|(CDS)2266999

    2017-01-01

    CERN has been involved in the dissemination of scientific results since its early days and has continuously updated the distribution channels. Currently, Inspire hosts catalogues of articles, authors, institutions, conferences, jobs, experiments, journals and more. Successful orientation among this amount of data requires comprehensive linking between the content. Inspire has lacked a system for linking experiments and articles together based on which accelerator they were conducted at. The purpose of this project has been to create such a system. Records for 156 accelerators were created and all 2913 experiments on Inspire were given corresponding MARC tags. Records of 18404 accelerator physics related bibliographic entries were also tagged with corresponding accelerator tags. Finally, as a part of the endeavour to broaden CERN's presence on Wikipedia, existing Wikipedia articles of accelerators were updated with short descriptions and links to Inspire. In total, 86 Wikipedia articles were updated. This repo...

  12. FMIT accelerator

    International Nuclear Information System (INIS)

    Armstrong, D.D.

    1983-01-01

    A 35-MeV 100-mA cw linear accelerator is being designed by Los Alamos for use in the Fusion Materials Irradiation Test (FMIT) Facility. Essential to this program is the design, construction, and evaluation of performance of the accelerator's injector, low-energy beam transport, and radio-frequency quadrupole sections before they are shipped to the facility site. The installation and testing of some of these sections have begun as well as the testing of the rf, noninterceptive beam diagnostics, computer control, dc power, and vacuum systems. An overview of the accelerator systems and the performance to date is given

  13. Electron accelerator

    International Nuclear Information System (INIS)

    Abramyan.

    1981-01-01

    The USSR produces an electron accelerator family of a simple design powered straight from the mains. The specifications are given of accelerators ELITA-400, ELITA-3, ELT-2, TEUS-3 and RIUS-5 with maximum electron energies of 0.3 to 5 MeV, a mean power of 10 to 70 kW operating in both the pulsed and the continuous (TEUS-3) modes. Pulsed accelerators ELITA-400 and ELITA-3 and RIUS-5 in which TESLA resonance transformers are used are characterized by their compact size. (Ha)

  14. Horizontal Accelerator

    Data.gov (United States)

    Federal Laboratory Consortium — The Horizontal Accelerator (HA) Facility is a versatile research tool available for use on projects requiring simulation of the crash environment. The HA Facility is...

  15. Acceleration theorems

    International Nuclear Information System (INIS)

    Palmer, R.

    1994-06-01

    Electromagnetic fields can be separated into near and far components. Near fields are extensions of static fields. They do not radiate, and they fall off more rapidly from a source than far fields. Near fields can accelerate particles, but the ratio of acceleration to source fields at a distance R, is always less than R/λ or 1, whichever is smaller. Far fields can be represented as sums of plane parallel, transversely polarized waves that travel at the velocity of light. A single such wave in a vacuum cannot give continuous acceleration, and it is shown that no sums of such waves can give net first order acceleration. This theorem is proven in three different ways; each method showing a different aspect of the situation

  16. LINEAR ACCELERATOR

    Science.gov (United States)

    Christofilos, N.C.; Polk, I.J.

    1959-02-17

    Improvements in linear particle accelerators are described. A drift tube system for a linear ion accelerator reduces gap capacity between adjacent drift tube ends. This is accomplished by reducing the ratio of the diameter of the drift tube to the diameter of the resonant cavity. Concentration of magnetic field intensity at the longitudinal midpoint of the external sunface of each drift tube is reduced by increasing the external drift tube diameter at the longitudinal center region.

  17. Pulsed-focusing recirculating linacs for muon acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Rolland [Muons, Inc., Batavia, IL (United States)

    2014-12-31

    Since the muon has a short lifetime, fast acceleration is essential for high-energy applications such as muon colliders, Higgs factories, or neutrino factories. The best one can do is to make a linear accelerator with the highest possible accelerating gradient to make the accelerating time as short as possible. However, the cost of such a single linear accelerator is prohibitively large due to expensive power sources, cavities, tunnels, and related infrastructure. As was demonstrated in the Thomas Jefferson Accelerator Facility (Jefferson Lab) Continuous Electron Beam Accelerator Facility (CEBAF), an elegant solution to reduce cost is to use magnetic return arcs to recirculate the beam through the accelerating RF cavities many times, where they gain energy on each pass. In such a Recirculating Linear Accelerator (RLA), the magnetic focusing strength diminishes as the beam energy increases in a conventional linac that has constant strength quadrupoles. After some number of passes the focusing strength is insufficient to keep the beam from going unstable and being lost. In this project, the use of fast pulsed quadrupoles in the linac sections was considered for stronger focusing as a function of time to allow more successive passes of a muon beam in a recirculating linear accelerator. In one simulation, it was shown that the number of passes could be increased from 8 to 12 using pulsed magnet designs that have been developed and tested. This could reduce the cost of linac sections of a muon RLA by 8/12, where more improvement is still possible. The expense of a greater number of passes and corresponding number of return arcs was also addressed in this project by exploring the use of ramped or FFAG-style magnets in the return arcs. A better solution, invented in this project, is to use combined-function dipole-quadrupole magnets to simultaneously transport two beams of different energies through one magnet string to reduce costs of return arcs by almost a factor of

  18. Accelerator microanalysis

    International Nuclear Information System (INIS)

    Tuniz, C.

    1997-01-01

    Particle accelerators have been developed more than sixty years ago to investigate nuclear and atomic phenomena. A major shift toward applications of accelerators in the study of materials structure and composition in inter-disciplinary projects has been witnessed in the last two decades. The Australian Nuclear Science and Technology Organisation (ANSTO) has developed advanced research programs based on the use of particle and photon beams. Atmospheric pollution problems are investigated at the 3 MV Van de Graff accelerator using ion beam analysis techniques to detect toxic elements in aerosol particles. High temperature superconductor and semiconductor materials are characterised using the recoil of iodine and other heavy ions produced at ANTARES, the 10-MV Tandem accelerator. A heavy-ion microprobe is presently being developed at ANTARES to map elemental concentrations of specific elements with micro-size resolution. An Accelerator mass Spectrometry (AMS) system has been developed at ANSTO for the ultra-sensitive detection of Carbon-14, Iodine-129 and other long-lived radioisotopes. This AMS spectrometer is a key instrument for climate change studies and international safeguards. ANSTO is also managing the Australian Synchrotron Research program based on facilities developed at the Photon Factory (Japan) and at the Advanced Photon Source (USA). Advanced projects in biology, materials chemistry, structural condensed matter and other disciplines are being promoted by a consortium involving Australian universities and research institutions. This paper will review recent advances in the use of particle accelerators, with a particular emphasis on applications developed at ANSTO and related to problems of international concern, such as global environmental change, public health and nuclear proliferation

  19. Accelerator operations

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    This section is concerned with the operation of both the tandem-linac system and the Dynamitron, two accelerators that are used for entirely different research. Developmental activities associated with the tandem and the Dynamitron are also treated here, but developmental activities associated with the superconducting linac are covered separately because this work is a program of technology development in its own right

  20. CNSTN Accelerator

    International Nuclear Information System (INIS)

    Habbassi, Afifa; Trabelsi, Adel

    2010-01-01

    This project give a big idea about the measurement of the linear accelerator in the CNSTN. During this work we control dose distribution for different product. For this characterisation we have to make an installation qualification ,operational qualification,performance qualification and of course for every step we have to control temperature and the dose ,even the distribution of the last one.

  1. Accelerators course

    CERN Multimedia

    CERN. Geneva HR-RFA; Métral, E

    2006-01-01

    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

  2. Accelerator operations

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    Operations of the SuperHILAC, the Bevatron/Bevalac, and the 184-inch Synchrocyclotron during the period from October 1977 to September 1978 are discussed. These include ion source development, accelerator facilities, the Heavy Ion Spectrometer System, and Bevelac biomedical operations

  3. Accelerator update

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    When the Accelerator Conference, combined International High Energy and US Particle versions, held in Dallas in May, was initially scheduled, progress nearby for the US Superconducting Supercollider was high on the preliminary agenda. With the SSC voted down by Congress in October 1993, this was no longer the case. However the content of the meeting, in terms of both its deep implications for ambitious new projects and the breadth of its scope, showed that the worldwide particle accelerator field is far from being moribund. A traditional feature of such accelerator conferences is the multiplicity of parallel sessions. No one person can attend all sessions, so that delegates can follow completely different paths and emerge with totally different impressions. Despite this overload, and despite the SSC cancellation, the general picture is one of encouraging progress over a wide range of major new projects throughout the world. At the same time, spinoff from, and applications of, accelerators and accelerator technology are becoming increasingly important. Centrestage is now CERN's LHC proton-proton collider, where a test string of superconducting magnets is operating over long periods at the nominal LHC field of 8.36 tesla or more. The assignment of the underground areas in the existing 27- kilometre LEP tunnel is now quasidefinitive (see page 3). For CERN's existing big machine, the LEP electron-positron collider, ongoing work concentrates on boosting performance using improved optics and bunch trains. But the main objective is the LEP2 scheme using superconducting accelerating cavities to boost the beam energy (see page 6). After some initial teething problems, production and operation of these cavities appears to have been mastered, at least under test conditions. A highlight at CERN last year was the first run with lead ions (December 1994, page 15). Handling these heavy particles with systems originally designed for protons calls for ingenuity. The SPS

  4. Accelerator update

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1995-09-15

    When the Accelerator Conference, combined International High Energy and US Particle versions, held in Dallas in May, was initially scheduled, progress nearby for the US Superconducting Supercollider was high on the preliminary agenda. With the SSC voted down by Congress in October 1993, this was no longer the case. However the content of the meeting, in terms of both its deep implications for ambitious new projects and the breadth of its scope, showed that the worldwide particle accelerator field is far from being moribund. A traditional feature of such accelerator conferences is the multiplicity of parallel sessions. No one person can attend all sessions, so that delegates can follow completely different paths and emerge with totally different impressions. Despite this overload, and despite the SSC cancellation, the general picture is one of encouraging progress over a wide range of major new projects throughout the world. At the same time, spinoff from, and applications of, accelerators and accelerator technology are becoming increasingly important. Centrestage is now CERN's LHC proton-proton collider, where a test string of superconducting magnets is operating over long periods at the nominal LHC field of 8.36 tesla or more. The assignment of the underground areas in the existing 27- kilometre LEP tunnel is now quasidefinitive (see page 3). For CERN's existing big machine, the LEP electron-positron collider, ongoing work concentrates on boosting performance using improved optics and bunch trains. But the main objective is the LEP2 scheme using superconducting accelerating cavities to boost the beam energy (see page 6). After some initial teething problems, production and operation of these cavities appears to have been mastered, at least under test conditions. A highlight at CERN last year was the first run with lead ions (December 1994, page 15). Handling these heavy particles with systems originally designed for protons calls for ingenuity. The SPS has managed

  5. Accelerating Value Creation with Accelerators

    DEFF Research Database (Denmark)

    Jonsson, Eythor Ivar

    2015-01-01

    and developing the best business ideas and support the due diligence process. Even universities are noticing that the learning experience of the action learning approach is an effective way to develop capabilities and change cultures. Accelerators related to what has historically been associated...

  6. Laser acceleration

    Science.gov (United States)

    Tajima, T.; Nakajima, K.; Mourou, G.

    2017-02-01

    The fundamental idea of Laser Wakefield Acceleration (LWFA) is reviewed. An ultrafast intense laser pulse drives coherent wakefield with a relativistic amplitude robustly supported by the plasma. While the large amplitude of wakefields involves collective resonant oscillations of the eigenmode of the entire plasma electrons, the wake phase velocity ˜ c and ultrafastness of the laser pulse introduce the wake stability and rigidity. A large number of worldwide experiments show a rapid progress of this concept realization toward both the high-energy accelerator prospect and broad applications. The strong interest in this has been spurring and stimulating novel laser technologies, including the Chirped Pulse Amplification, the Thin Film Compression, the Coherent Amplification Network, and the Relativistic Mirror Compression. These in turn have created a conglomerate of novel science and technology with LWFA to form a new genre of high field science with many parameters of merit in this field increasing exponentially lately. This science has triggered a number of worldwide research centers and initiatives. Associated physics of ion acceleration, X-ray generation, and astrophysical processes of ultrahigh energy cosmic rays are reviewed. Applications such as X-ray free electron laser, cancer therapy, and radioisotope production etc. are considered. A new avenue of LWFA using nanomaterials is also emerging.

  7. Laser acceleration

    International Nuclear Information System (INIS)

    Tajima, T.; Nakajima, K.; Mourou, G.

    2017-01-01

    The fundamental idea of LaserWakefield Acceleration (LWFA) is reviewed. An ultrafast intense laser pulse drives coherent wakefield with a relativistic amplitude robustly supported by the plasma. While the large amplitude of wake fields involves collective resonant oscillations of the eigenmode of the entire plasma electrons, the wake phase velocity ∼ c and ultra fastness of the laser pulse introduce the wake stability and rigidity. A large number of worldwide experiments show a rapid progress of this concept realization toward both the high-energy accelerator prospect and broad applications. The strong interest in this has been spurring and stimulating novel laser technologies, including the Chirped Pulse Amplification, the Thin Film Compression, the Coherent Amplification Network, and the Relativistic Mirror Compression. These in turn have created a conglomerate of novel science and technology with LWFA to form a new genre of high field science with many parameters of merit in this field increasing exponentially lately. This science has triggered a number of worldwide research centers and initiatives. Associated physics of ion acceleration, X-ray generation, and astrophysical processes of ultrahigh energy cosmic rays are reviewed. Applications such as X-ray free electron laser, cancer therapy, and radioisotope production etc. are considered. A new avenue of LWFA using nano materials is also emerging.

  8. Accelerating networks

    International Nuclear Information System (INIS)

    Smith, David M D; Onnela, Jukka-Pekka; Johnson, Neil F

    2007-01-01

    Evolving out-of-equilibrium networks have been under intense scrutiny recently. In many real-world settings the number of links added per new node is not constant but depends on the time at which the node is introduced in the system. This simple idea gives rise to the concept of accelerating networks, for which we review an existing definition and-after finding it somewhat constrictive-offer a new definition. The new definition provided here views network acceleration as a time dependent property of a given system as opposed to being a property of the specific algorithm applied to grow the network. The definition also covers both unweighted and weighted networks. As time-stamped network data becomes increasingly available, the proposed measures may be easily applied to such empirical datasets. As a simple case study we apply the concepts to study the evolution of three different instances of Wikipedia, namely, those in English, German, and Japanese, and find that the networks undergo different acceleration regimes in their evolution

  9. Advanced concepts for acceleration

    International Nuclear Information System (INIS)

    Keefe, D.

    1986-07-01

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

  10. Theoretical aspects of the CEBAF 89-009 experiment on inclusive scattering of 4.05 GeV electrons from nuclei

    International Nuclear Information System (INIS)

    Avraham Rinat; Taragin, M.F.

    1999-01-01

    We compare recent CEBAF data on inclusive electron scattering of 4.05 GeV electrons on nuclei with predictions, based on a relation between structure functions (SF) of a nucleus, a nucleon, and a nucleus of point nucleons. The latter contains nuclear dynamics, e.g., binary collision contributions in addition to the asymptotic limit. The agreement with data is good, except in low-intensity regions. Computed ternary collision contributions appear too small for an explanation. We perform scaling analyses in Gurvitz's scaling variable and find that for y G (gt o r l t) 0, ratios of scaling functions for pairs of nuclei differ by less than 15-20% from 1. Scaling functions for (y G 2 , shown to approach a plateau from above. We observe only weak Q 2 dependence in final-state interactions (FSI), which in the relevant kinematic region is ascribed to the diffractive nature of NN amplitudes appearing in FSI. This renders it difficult to separate asymptotic from FSI parts and seriously hampers the extraction of n(p) from scaling analyses in a model-independent fashion

  11. Accelerators and the Accelerator Community

    Energy Technology Data Exchange (ETDEWEB)

    Malamud, Ernest; Sessler, Andrew

    2008-06-01

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

  12. Accelerators and the Accelerator Community

    International Nuclear Information System (INIS)

    Malamud, Ernest; Sessler, Andrew

    2008-01-01

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

  13. Optimization of the RF cavity heat load and trip rates for CEBAF at 12 GeV

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, He [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Roblin, Yves R. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Freyberger, Arne P. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Krafft, Geoffrey A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Terzic, Balsa P. [Old Dominion Univ., Norfolk, VA (United States)

    2017-05-01

    The Continuous Electron Beam Accelerator Facility at JLab has 200 RF cavities in the north linac and the south linac respectively after the 12 GeV upgrade. The purpose of this work is to simultaneously optimize the heat load and the trip rate for the cavities and to reconstruct the pareto-optimal front in a timely manner when some of the cavities are turned down. By choosing an efficient optimizer and strategically creating the initial gradients, the pareto-optimal front for no more than 15 cavities down can be re-established within 20 seconds.

  14. Ring accelerators

    International Nuclear Information System (INIS)

    Gisler, G.; Faehl, R.

    1983-01-01

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

  15. accelerating cavity

    CERN Multimedia

    On the inside of the cavity there is a layer of niobium. Operating at 4.2 degrees above absolute zero, the niobium is superconducting and carries an accelerating field of 6 million volts per metre with negligible losses. Each cavity has a surface of 6 m2. The niobium layer is only 1.2 microns thick, ten times thinner than a hair. Such a large area had never been coated to such a high accuracy. A speck of dust could ruin the performance of the whole cavity so the work had to be done in an extremely clean environment.

  16. Cosmic ray acceleration mechanisms

    International Nuclear Information System (INIS)

    Cesarsky, C.J.

    1982-09-01

    We present a brief summary of some of the most popular theories of cosmic ray acceleration: Fermi acceleration, its application to acceleration by shocks in a scattering medium, and impulsive acceleration by relativistic shocks

  17. Results from CEBAF experiment E89-012: Measurements of deuteron photo-disintegration up to 4 GeV

    International Nuclear Information System (INIS)

    Mike Miller; David Abbott; Abdellah Ahmidouch; Chris Armstrong; John Arrington; K. A. Assamagan; Oliver K. Baker; S. P. Barrow; D. P. Beatty; D. H. Beck; S. Y. Beedoe; Elizabeth Beise; J. E. Belz; 0 C. W. Bochna; Peter Bosted; Ed Brash; Herbert Breuer; R. V. Cadman; Larry Cardman; Roger Carlini; Jinseok Cha; Nicholas Chant; G. Collins; C. Cothran; W. J. Cummings; Samuel Danagoulian; F. A. Duncan; J. A. Dunne; Dipangkar Dutta; Tom Eden; Rolf Ent; Bradley Filippone; Tony A. Forest; H. T. Fortune; Valera V. Frolov; Haiyan Gao; Donald Geesaman; Ron Gilman; Paul Gueye; Kenneth Gustafsson; Jens-Ole Hansen; M. Harvey; Wendy Hinton; R. J. Holt; Hal Jackson; Cynthia Keppel; M. A. Khandaker; Ed Kinney; Andi Klein; 0 Doug Koltenuk; Gerfried Kumbartzki; Allison Lung; David Mack; Richard Madey; Pete Markowitz; Kenneth McFarlane; Robert McKeown; David Meekins; Z-E. Meziani; J. H. Mitchell; Hamlet Mkrtchyan; R. M. Mohring; James Napolitano; Alan Nathan; Gabriel Niculescu; Ioana Niculescu; Tom O'Neill; B. R. Owen; S. Pate; Dave Potterveld; John Price; G. L. Rakness; Ronald Ransome; Juerg Reinhold; Paul Rutt; G. Savage; Ralph Segel; N. Simicevic; Paul Stoler; Riad Suleiman; Liguang Tang; B. P. Terburg; D. Van Westrum; Bill Vulcan; S. E. Williamson; Michael Witkowski; Stephen Wood; Chen Yan; Ben Zeidman

    1997-01-01

    The first measurements of differential cross sections for deuteron photo-disintegration at photon energies up to 4 GeV were performed at the Thomas Jefferson National Accelerator Facility early in 1996. Cross section results for D(gamma,p)n at proton center of mass angle of 35 o , 53 o and 90 o will be presented. These results are in good agreement with previous measurements at low energy and extend to higher energies where data were previously unavailable. The 90 o degree data show behavior consistent with the constituent counting rules up to 4 GeV and are also in fair agreement with the asymptotic meson exchange model. The 37 o and 53 o data do not show clear signs of counting rule behavior, although a threshold in transverse momentum for the onset of scaling cannot be excluded

  18. Evaluating the Potential of Commercial GIS for Accelerator Configuration Management

    International Nuclear Information System (INIS)

    Larrieu, T.L.; Roblin, Y.R.; White, K.; Slominski, R.

    2005-01-01

    The Geographic Information System (GIS) is a tool used by industries needing to track information about spatially distributed assets. A water utility, for example, must know not only the precise location of each pipe and pump, but also the respective pressure rating and flow rate of each. In many ways, an accelerator such as CEBAF (Continuous Electron Beam Accelerator Facility) can be viewed as an ''electron utility''. Whereas the water utility uses pipes and pumps, the ''electron utility'' uses magnets and RF cavities. At Jefferson lab we are exploring the possibility of implementing ESRI's ArcGIS as the framework for building an all-encompassing accelerator configuration database that integrates location, configuration, maintenance, and connectivity details of all hardware and software. The possibilities of doing so are intriguing. From the GIS, software such as the model server could always extract the most-up-to-date layout information maintained by the Survey and Alignment for lattice modeling. The Mechanical Engineering department could use ArcGIS tools to generate CAD drawings of machine segments from the same database. Ultimately, the greatest benefit of the GIS implementation could be to liberate operators and engineers from the limitations of the current system-by-system view of machine configuration and allow a more integrated regional approach. The commercial GIS package provides a rich set of tools for database-connectivity, versioning, distributed editing, importing and exporting, and graphical analysis and querying, and therefore obviates the need for much custom development. However, formidable challenges to implementation exist and these challenges are not only technical and manpower issues, but also organizational ones. The GIS approach would crosscut organizational boundaries and require departments, which heretofore have had free reign to manage their own data, to cede some control and agree to a centralized framework

  19. Evaluating the Potential of Commercial GIS for Accelerator Configuration Management

    Energy Technology Data Exchange (ETDEWEB)

    T.L. Larrieu; Y.R. Roblin; K. White; R. Slominski

    2005-10-10

    The Geographic Information System (GIS) is a tool used by industries needing to track information about spatially distributed assets. A water utility, for example, must know not only the precise location of each pipe and pump, but also the respective pressure rating and flow rate of each. In many ways, an accelerator such as CEBAF (Continuous Electron Beam Accelerator Facility) can be viewed as an ''electron utility''. Whereas the water utility uses pipes and pumps, the ''electron utility'' uses magnets and RF cavities. At Jefferson lab we are exploring the possibility of implementing ESRI's ArcGIS as the framework for building an all-encompassing accelerator configuration database that integrates location, configuration, maintenance, and connectivity details of all hardware and software. The possibilities of doing so are intriguing. From the GIS, software such as the model server could always extract the most-up-to-date layout information maintained by the Survey & Alignment for lattice modeling. The Mechanical Engineering department could use ArcGIS tools to generate CAD drawings of machine segments from the same database. Ultimately, the greatest benefit of the GIS implementation could be to liberate operators and engineers from the limitations of the current system-by-system view of machine configuration and allow a more integrated regional approach. The commercial GIS package provides a rich set of tools for database-connectivity, versioning, distributed editing, importing and exporting, and graphical analysis and querying, and therefore obviates the need for much custom development. However, formidable challenges to implementation exist and these challenges are not only technical and manpower issues, but also organizational ones. The GIS approach would crosscut organizational boundaries and require departments, which heretofore have had free reign to manage their own data, to cede some control and agree to a

  20. Electron accelerators for research at the frontiers of nuclear physics

    International Nuclear Information System (INIS)

    Grunder, H.A.; Hartline, B.K.; Corneliussen, S.T.

    1986-01-01

    Electron accelerators for the frontiers of nuclear physics must provide high duty factor (>80%) for coincidence measurements; few-hundred-MeV through few-GeV energy for work in the nucleonic, hadronic, and confinement regimes; energy resolution of ∼10 -4 ; and high current (≥ 100 μA). To fulfill these requirements new machines and upgrades of existing ones are being planned or constructed. Representative microtron-based facilities are the upgrade of MAMI at the University of Mainz (West Germany), the proposed two-stage cascaded microtron at the University of Illinois (USA), and the three-stage Troitsk ''polytron'' (USSR). Representative projects to add pulse stretcher rings to existing linacs are the upgrades at MIT-Bates (USA) and at NIKHEF-K (Netherlands). Recent advances in superconducting rf technology, especially in cavity design and fabrication, have made large superconducting cw linacs become feasible. Recirculating superconducting cw linacs are under construction at the University of Darmstadt (West Germany) and at CEBAF (USA), and a proposal is being developed at Saclay (France). 31 refs

  1. Sector ring accelerator ''RESATRON''

    International Nuclear Information System (INIS)

    Schwabe, E.

    1980-01-01

    Project of sector ring accelerator RESATRON is described. The curiosity of this accelerator is the second cycle of acceleration of the beam after stripping it on the foil. In such an accelerator heavy ions with a different ratio Z to A can be accelerated. (S.B.)

  2. Multiperiodic accelerator structures for linear particle accelerators

    International Nuclear Information System (INIS)

    Tran, D.T.

    1975-01-01

    High efficiency linear accelerator structures, comprised of a succession of cylindrical resonant cavities for acceleration, are described. Coupling annular cavities are located at the periphery, each being coupled to two adjacent cylindrical cavities. (auth)

  3. Accelerators of atomic particles

    International Nuclear Information System (INIS)

    Sarancev, V.

    1975-01-01

    A brief survey is presented of accelerators and methods of accelerating elementary particles. The principle of collective accelerating of elementary particles is clarified and the problems are discussed of its realization. (B.S.)

  4. Accelerators of future generation

    International Nuclear Information System (INIS)

    Kolomenskij, A.A.

    1983-01-01

    A brief review of the prospects of development of various of types accelerator over next 10 to 15 years is given. The following directions are considered: superhign energy proton accelerators and storage rings, electron-positron colliding beams, heavy ion accelerators, medium energy, high-current proton accelerators superhigh power particle beams (electrons light- and heavy ions) for inertial fusion

  5. Future accelerator technology

    International Nuclear Information System (INIS)

    Sessler, A.M.

    1986-05-01

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

  6. Recent Progress in Power Refrigeration below 2 K for Superconducting Accelerators

    CERN Document Server

    Claudet, Serge

    2005-01-01

    As a result of technico-economical optimization and quest for increased performance, 2 K cryogenics is now present in large accelerator projects using superconducting magnets or acceleration cavities. Consequently, large cryogenic systems producing refrigeration capacity below 2 K in the kW range and with high efficiency over a large dynamic range are needed. After CEBAF and SNS, this is the case for the Large Hadron Collider (LHC) project at CERN for which eight 2.4 kW @ 1.8 K refrigeration units are needed to cool each a 3.3 km long sector of high-field magnets. Combining cold hydrodynamic compressors in series with warm volumetric compressors, complete pre-series units as well as sets of series cold compressors have been intensively tested and validated from two different industrial suppliers. After recalling the possible 2 K refrigeration cycles and their comparative merits, this paper describes the specific features of the LHC system and presents the achieved performance with emphasis on the progress in...

  7. 2014 CERN Accelerator Schools: Plasma Wake Acceleration

    CERN Multimedia

    2014-01-01

    A specialised school on Plasma Wake Acceleration will be held at CERN, Switzerland from 23-29 November, 2014.   This course will be of interest to staff and students in accelerator laboratories, university departments and companies working in or having an interest in the field of new acceleration techniques. Following introductory lectures on plasma and laser physics, the course will cover the different components of a plasma wake accelerator and plasma beam systems. An overview of the experimental studies, diagnostic tools and state of the art wake acceleration facilities, both present and planned, will complement the theoretical part. Topical seminars and a visit of CERN will complete the programme. Further information can be found at: http://cas.web.cern.ch/cas/PlasmaWake2014/CERN-advert.html http://indico.cern.ch/event/285444/

  8. Target raster system at CEBAF

    International Nuclear Information System (INIS)

    Yan, C.; Adderley, P.; Carlini, R.; Cuevas, C.; Vulcan, W.; Wines, R.

    1995-01-01

    A fast raster (FR) system consisting of two Litz cable air-core magnets (x, y) has been installed and tested in the Hall C beam line tunnel, 21 m from the cryogenic target. The system provides a maximum deflection of 0.06 mrad at a frequency range of 15-45 kHz for a 6 GeV electron beam. The FR magnets are driven by a MOSFET bipolar switching power source with a triangle current waveform, the peak-to-peak current is 40 A. (orig.)

  9. Other people's accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1987-06-15

    The first report from the Washington Accelerator Conference concentrated on news from the particle physics centres. But the bulk of the Conference covered the use of accelerators in other fields, underlining this valuable spinoff from particle physics.

  10. Improved plasma accelerator

    Science.gov (United States)

    Cheng, D. Y.

    1971-01-01

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

  11. The electron accelerator Ridgetron

    International Nuclear Information System (INIS)

    Hayashizaki, N.; Hattori, T.; Odera, M.; Fujisawa, T.

    1999-01-01

    Many electron accelerators of DC or RF type have been widely used for electron beam irradiation (curing, crosslinking of polymers, sterilization of medical disposables, preservation of food, etc.). Regardless of the acceleration energy, the accelerators to be installed in industrial facilities, have to satisfy the requires of compact size, low power consumption and stable operation. The DC accelerator is realized very compact in the energy under 300 keV, however, it is large to prevent the discharge of an acceleration column in the energy over 300 keV. The RF electron accelerator Ridgetron has been developed to accelerate the continuous beam of the 0.5-10 MeV range in compact space. It is the first example as an electron accelerator incorporated a ridged RF cavity. A prototype system of final energy of 2.5 MeV has been studied to confirm the feasibility at present

  12. High brightness electron accelerator

    International Nuclear Information System (INIS)

    Sheffield, R.L.; Carlsten, B.E.; Young, L.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 accelerating cavities having end walls with four coupling slots for accelerating electrons to high velocities in the absence of quadrupole fields. A second plurality of cavities receives the high velocity electrons for further acceleration, where each of the second cavities has end walls with two coupling slots for acceleration in the absence of dipole fields. The accelerator also includes a first cavity with an extended length to provide for phase matching the electron beam along the accelerating cavities. A solenoid is provided about the photocathode that emits the electrons, where the solenoid is configured to provide a substantially uniform magnetic field over the photocathode surface to minimize emittance of the electrons as the electrons enter the first cavity. 5 figs

  13. Unified accelerator libraries

    International Nuclear Information System (INIS)

    Malitsky, Nikolay; Talman, Richard

    1997-01-01

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

  14. YEREVAN: Acceleration workshop

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    Sponsored by the Yerevan Physics Institute in Armenia, a Workshop on New Methods of Charged Particle Acceleration in October near the Nor Amberd Cosmic Ray Station attracted participants from most major accelerator centres in the USSR and further afield

  15. San Francisco Accelerator Conference

    International Nuclear Information System (INIS)

    Southworth, Brian

    1991-01-01

    'Where are today's challenges in accelerator physics?' was the theme of the open session at the San Francisco meeting, the largest ever gathering of accelerator physicists and engineers

  16. Large tandem accelerators

    International Nuclear Information System (INIS)

    Jones, C.M.

    1976-01-01

    The increasing importance of energetic heavy ion beams in the study of atomic physics, nuclear physics, and materials science has partially or wholly motivated the construction of a new generation of tandem accelerators designed to operate at maximum terminal potentials in the range 14 to 30 MV. In addition, a number of older tandem accelerators are now being significantly upgraded to improve their heavy ion performance. Both of these developments have reemphasized the importance of negative heavy ion sources. The new large tandem accelerators are described, and the requirements placed on negative heavy ion source technology by these and other tandem accelerators used for the acceleration of heavy ions are discussed. First, a brief description is given of the large tandem accelerators which have been completed recently, are under construction, or are funded for construction, second, the motivation for construction of these accelerators is discussed, and last, criteria for negative ion sources for use with these accelerators are presented

  17. Vp x B acceleration

    International Nuclear Information System (INIS)

    Sugihara, Ryo.

    1987-05-01

    A unique particle acceleration by an electrostatic (ES) wave, a magnetosonic shock wave as well as an electromagnetic (EM) wave is reviewed. The principle of the acceleration is that when a charged particle is carried across an external magnetic field the charge feels a DC field (the Lorentz force) and is accelerated. The theory for the ES wave acceleration is experimentally verified thought it is semi-quantitative. The shock acceleration is extensively studied theoretically and in a particle simulation method and the application is extended to phenomena in interplanetary space. The EM wave acceleration is based on a trapping in a moving neutral sheet created by the wave magnetic field and the external magnetic field, and the particle can be accelerated indefinitely. A brief sketch on a slow-wave-structure for this acceleration will be given. (author)

  18. Accelerator-timing system

    International Nuclear Information System (INIS)

    Timmer, E.; Heine, E.

    1985-01-01

    Along the NIKHEF accelerator in Amsterdam (Netherlands), at several places a signal is needed for the sychronisation of all devices with the acceleration process. In this report, basic principles and arrangements of this timing system are described

  19. Linear accelerator: A concept

    Science.gov (United States)

    Mutzberg, J.

    1972-01-01

    Design is proposed for inexpensive accelerometer which would work by applying pressure to fluid during acceleration. Pressure is used to move shuttle, and shuttle movement is sensed and calibrated to give acceleration readings.

  20. Heavy ion accelerators

    International Nuclear Information System (INIS)

    Schmelzer, C.

    1974-01-01

    This review of the present state of work on heavy-ion accelerators pays particular attention to the requirements for nuclear research. It is divided into the following sections: single-particle versus collective acceleration, heavy-ion accelerators, beam quality, and a status report on the UNILAC facility. Among the topics considered are the recycling cyclotron, linacs with superconducting resonators, and acceleration to the GeV/nucleon range. (8 figures, 2 tables) (U.S.)

  1. Accelerators at school

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    Latest subject covered by the CERN Accelerator School was 'Applied Geodesy of Particle Accelerators', which attracted an impressive number of outside participants to CERN for a week in April. Since the forerunners of today's particle accelerators were demonstrated over 50 years ago, the positioning of accelerator components has progressed from the laboratory bench-top to tunnels tens of kilometres long. Despite this phenomenal growth in size, sub-millimetre accuracy is still required

  2. Accelerators at school

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1986-06-15

    Latest subject covered by the CERN Accelerator School was 'Applied Geodesy of Particle Accelerators', which attracted an impressive number of outside participants to CERN for a week in April. Since the forerunners of today's particle accelerators were demonstrated over 50 years ago, the positioning of accelerator components has progressed from the laboratory bench-top to tunnels tens of kilometres long. Despite this phenomenal growth in size, sub-millimetre accuracy is still required.

  3. Accelerators for Medicine

    CERN Multimedia

    CERN. Geneva

    2018-01-01

    This lecture will review the different applications of particle accelerators to the medical field, from cancer treatment with beams of accelerator-produced particles (photons, electrons, protons, ions and neutrons) to the generation of radioactive isotopes used in medical diagnostics, in cancer therapy and in the new domain of theragnostics. For each application will be outlined the state of the art, the potential, and the accelerator challenges to be faced to meet the increasing demand for therapeutic procedures based on accelerators.

  4. Large electrostatic accelerators

    International Nuclear Information System (INIS)

    Jones, C.M.

    1984-01-01

    The paper is divided into four parts: a discussion of the motivation for the construction of large electrostatic accelerators, a description and discussion of several large electrostatic accelerators which have been recently completed or are under construction, a description of several recent innovations which may be expected to improve the performance of large electrostatic accelerators in the future, and a description of an innovative new large electrostatic accelerator whose construction is scheduled to begin next year

  5. Particle beam accelerator

    International Nuclear Information System (INIS)

    Turner, N.L.

    1982-01-01

    A particle beam accelerator is described which has several electrodes that are selectively short circuited together synchronously with changes in the magnitude of a DC voltage applied to the accelerator. By this method a substantially constant voltage gradient is maintained along the length of the unshortened electrodes despite variations in the energy applied to the beam by the accelerator. The invention has particular application to accelerating ion beams that are implanted into semiconductor wafers. (U.K.)

  6. Superconducting accelerator technology

    International Nuclear Information System (INIS)

    Grunder, H.A.; Hartline, B.K.

    1986-01-01

    Modern and future accelerators for high energy and nuclear physics rely increasingly on superconducting components to achieve the required magnetic fields and accelerating fields. This paper presents a practical overview of the phenomenon of superconductivity, and describes the design issues and solutions associated with superconducting magnets and superconducting rf acceleration structures. Further development and application of superconducting components promises increased accelerator performance at reduced electric power cost

  7. Applications of particle accelerators

    International Nuclear Information System (INIS)

    Barbalat, O.

    1994-01-01

    Particle accelerators are now widely used in a variety of applications for scientific research, applied physics, medicine, industrial processing, while possible utilisation in power engineering is envisaged. Earlier presentations of this subject, given at previous CERN Accelerator School sessions have been updated with papers contributed to the first European Conference on Accelerators in Applied Research and Technology (ECAART) held in September 1989 in Frankfurt and to the Second European Particle Accelerator Conference in Nice in June 1990. (orig.)

  8. The CERN Accelerator School

    CERN Multimedia

    2016-01-01

    Introduction to accelerator physics The CERN Accelerator School: Introduction to Accelerator Physics, which should have taken place in Istanbul, Turkey, later this year has now been relocated to Budapest, Hungary.  Further details regarding the new hotel and dates will be made available as soon as possible on a new Indico site at the end of May.

  9. Angular Acceleration without Torque?

    Science.gov (United States)

    Kaufman, Richard D.

    2012-01-01

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

  10. Accelerators and Dinosaurs

    CERN Multimedia

    Turner, Michael Stanley

    2003-01-01

    Using naturally occuring particles on which to research might have made accelerators become extinct. But in fact, results from astrophysics have made accelerator physics even more important. Not only are accelerators used in hospitals but they are also being used to understand nature's inner workings by searching for Higgs bosons, CP violation, neutrino mass and dark matter (2 pages)

  11. Far field acceleration

    International Nuclear Information System (INIS)

    Fernow, R.C.

    1995-07-01

    Far fields are propagating electromagnetic waves far from their source, boundary surfaces, and free charges. The general principles governing the acceleration of charged particles by far fields are reviewed. A survey of proposed field configurations is given. The two most important schemes, Inverse Cerenkov acceleration and Inverse free electron laser acceleration, are discussed in detail

  12. Virtual Accelerator for Accelerator Optics Improvement

    CERN Document Server

    Yan Yi Ton; Decker, Franz Josef; Ecklund, Stanley; Irwin, John; Seeman, John; Sullivan, Michael K; Turner, J L; Wienands, Ulrich

    2005-01-01

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

  13. The Accelerator Reliability Forum

    CERN Document Server

    Lüdeke, Andreas; Giachino, R

    2014-01-01

    A high reliability is a very important goal for most particle accelerators. The biennial Accelerator Reliability Workshop covers topics related to the design and operation of particle accelerators with a high reliability. In order to optimize the over-all reliability of an accelerator one needs to gather information on the reliability of many different subsystems. While a biennial workshop can serve as a platform for the exchange of such information, the authors aimed to provide a further channel to allow for a more timely communication: the Particle Accelerator Reliability Forum [1]. This contribution will describe the forum and advertise it’s usage in the community.

  14. Notes on Laser Acceleration

    International Nuclear Information System (INIS)

    Tajima, T.

    2008-01-01

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

  15. Industrial Application of Accelerators

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    At CERN, we are very familiar with large, high energy particle accelerators. However, in the world outside CERN, there are more than 35000 accelerators which are used for applications ranging from treating cancer, through making better electronics to removing harmful micro-organisms from food and water. These are responsible for around $0.5T of commerce each year. Almost all are less than 20 MeV and most use accelerator types that are somewhat different from what is at CERN. These lectures will describe some of the most common applications, some of the newer applications in development and the accelerator technology used for them. It will also show examples of where technology developed for particle physics is now being studied for these applications. Rob Edgecock is a Professor of Accelerator Science, with a particular interest in the medical applications of accelerators. He works jointly for the STFC Rutherford Appleton Laboratory and the International Institute for Accelerator Applications at the Univer...

  16. Industrial Application of Accelerators

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    At CERN, we are very familiar with large, high energy particle accelerators. However, in the world outside CERN, there are more than 35000 accelerators which are used for applications ranging from treating cancer, through making better electronics to removing harmful micro-organisms from food and water. These are responsible for around $0.5T of commerce each year. Almost all are less than 20 MeV and most use accelerator types that are somewhat different from what is at CERN. These lectures will describe some of the most common applications, some of the newer applications in development and the accelerator technology used for them. It will also show examples of where technology developed for particle physics is now being studied for these applications. Rob Edgecock is a Professor of Accelerator Science, with a particular interest in the medical applications of accelerators. He works jointly for the STFC Rutherford Appleton Laboratory and the International Institute for Accelerator Applications at the Uni...

  17. Accelerations in Flight

    Science.gov (United States)

    Doolittle, J H

    1925-01-01

    This work on accelerometry was done at McCook Field for the purpose of continuing the work done by other investigators and obtaining the accelerations which occur when a high-speed pursuit airplane is subjected to the more common maneuvers. The accelerations obtained in suddenly pulling out of a dive with well-balanced elevators are shown to be within 3 or 4 per cent of the theoretically possible accelerations. The maximum acceleration which a pilot can withstand depends upon the length of time the acceleration is continued. It is shown that he experiences no difficulty under the instantaneous accelerations as high as 7.8 G., but when under accelerations in excess of 4.5 G., continued for several seconds, he quickly loses his faculties.

  18. Accelerators for energy

    International Nuclear Information System (INIS)

    Inoue, Makoto

    2000-01-01

    A particle accelerator is a device to consume energy but not to produce it. Then, the titled accelerator seems to mean an accelerator for using devices related to nuclear energy. For an accelerator combined to nuclear fissionable fuel, neutron sources are D-T type, (gamma, n) reaction using electron beam type spallation type, and so forth. At viewpoints of powers of incident beam and formed neutron, a spallation type source using high energy proton is told to be effective but others have some advantages by investigation on easy operability, easy construction, combustion with target, energy and directivity of neutron, and so forth. Here were discussed on an accelerator for research on accelerator driven energy system by dividing its researching steps, and on kind, energy, beam intensity, and so forth of an accelerator suitable for it. And, space electric charge effect at beam propagation direction controlled by beam intensity of cyclotron was also commented. (G.K.)

  19. Particle-accelerator decommissioning

    International Nuclear Information System (INIS)

    Opelka, J.H.; Mundis, R.L.; Marmer, G.J.; Peterson, J.M.; Siskind, B.; Kikta, M.J.

    1979-12-01

    Generic considerations involved in decommissioning particle accelerators are examined. There are presently several hundred accelerators operating in the United States that can produce material containing nonnegligible residual radioactivity. Residual radioactivity after final shutdown is generally short-lived induced activity and is localized in hot spots around the beam line. The decommissioning options addressed are mothballing, entombment, dismantlement with interim storage, and dismantlement with disposal. The recycle of components or entire accelerators following dismantlement is a definite possibility and has occurred in the past. Accelerator components can be recycled either immediately at accelerator shutdown or following a period of storage, depending on the nature of induced activation. Considerations of cost, radioactive waste, and radiological health are presented for four prototypic accelerators. Prototypes considered range from small accelerators having minimal amounts of radioactive mmaterial to a very large accelerator having massive components containing nonnegligible amounts of induced activation. Archival information on past decommissionings is presented, and recommendations concerning regulations and accelerator design that will aid in the decommissioning of an accelerator are given

  20. An introduction to acceleration mechanisms

    International Nuclear Information System (INIS)

    Palmer, R.B.

    1987-05-01

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

  1. Recirculating accelerator driver for a high-power free-electron laser: A design overview

    International Nuclear Information System (INIS)

    Bohn, C.L.

    1997-01-01

    Jefferson Lab is building a free-electron laser (FEL) to produce continuous-wave (cw), kW-level light at 3-6 μm wavelength. A superconducting linac will drive the laser, generating a 5 mA average current, 42 MeV energy electron beam. A transport lattice will recirculate the beam back to the linac for deceleration and conversion of about 75% of its power into rf power. Bunch charge will range up to 135 pC, and bunch lengths will range down to 1 ps in parts of the transport lattice. Accordingly, space charge in the injector and coherent synchrotron radiation in magnetic bends come into play. The machine will thus enable studying these phenomena as a precursor to designing compact accelerators of high-brightness beams. The FEL is scheduled to be installed in its own facility by 1 October 1997. Given the short schedule, the machine design is conservative, based on modifications of the CEBAF cryomodule and MIT-Bates transport lattice. This paper surveys the machine design

  2. Recirculating accelerator driver for a high-power free-electron laser: A design overview

    Energy Technology Data Exchange (ETDEWEB)

    Bohn, C.L. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    1997-06-01

    Jefferson Lab is building a free-electron laser (FEL) to produce continuous-wave (cw), kW-level light at 3-6 {mu}m wavelength. A superconducting linac will drive the laser, generating a 5 mA average current, 42 MeV energy electron beam. A transport lattice will recirculate the beam back to the linac for deceleration and conversion of about 75% of its power into rf power. Bunch charge will range up to 135 pC, and bunch lengths will range down to 1 ps in parts of the transport lattice. Accordingly, space charge in the injector and coherent synchrotron radiation in magnetic bends come into play. The machine will thus enable studying these phenomena as a precursor to designing compact accelerators of high-brightness beams. The FEL is scheduled to be installed in its own facility by 1 October 1997. Given the short schedule, the machine design is conservative, based on modifications of the CEBAF cryomodule and MIT-Bates transport lattice. This paper surveys the machine design.

  3. Accelerator and radiation physics

    CERN Document Server

    Basu, Samita; Nandy, Maitreyee

    2013-01-01

    "Accelerator and radiation physics" encompasses radiation shielding design and strategies for hadron therapy accelerators, neutron facilities and laser based accelerators. A fascinating article describes detailed transport theory and its application to radiation transport. Detailed information on planning and design of a very high energy proton accelerator can be obtained from the article on radiological safety of J-PARC. Besides safety for proton accelerators, the book provides information on radiological safety issues for electron synchrotron and prevention and preparedness for radiological emergencies. Different methods for neutron dosimetry including LET based monitoring, time of flight spectrometry, track detectors are documented alongwith newly measured experimental data on radiation interaction with dyes, polymers, bones and other materials. Design of deuteron accelerator, shielding in beam line hutches in synchrotron and 14 MeV neutron generator, various radiation detection methods, their characteriza...

  4. 2014 Accelerators meeting, Grenoble

    International Nuclear Information System (INIS)

    Lucotte, Arnaud; Lamy, Thierry; De Conto, Jean-Marie; Fontaine, Alain; Revol, Jean-Luc; Nadolski, Laurent S.; Kazamias, Sophie; Vretenar, Maurizio; Ferrando, Philippe; Laune, Bernard; Vedrine, Pierre

    2014-10-01

    The Accelerators meeting is organised every two years by the Accelerators division of the French Society of Physics (SFP). It brings together about 50 participants during a one-day meeting. The morning sessions are devoted to scientific presentations while the afternoon is dedicated to technical visits of facilities. This document brings together the available presentations (slides): 1 - Presentation of the Laboratory of subatomic physics and cosmology - LPSC-Grenoble (Lucotte, Arnaud; Lamy, Thierry); 2 - Presentation of the Accelerators division of the French Society of Physics (Fontaine, Alain; Revol, Jean-Luc); 3 - Presentation of Grenoble's master diplomas in Accelerator physics (Nadolski, Laurent S.); 4 - Presentation of Paris' master diplomas in big instruments (Kazamias, Sophie); 5 - Particle accelerators and European Union's projects (Vretenar, Maurizio); 6 - French research infrastructures (Ferrando, Philippe); 7 - Coordination of accelerators activity in France (Laune, Bernard; Vedrine, Pierre)

  5. Accelerator reliability workshop

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, L; Duru, Ph; Koch, J M; Revol, J L; Van Vaerenbergh, P; Volpe, A M; Clugnet, K; Dely, A; Goodhew, D

    2002-07-01

    About 80 experts attended this workshop, which brought together all accelerator communities: accelerator driven systems, X-ray sources, medical and industrial accelerators, spallation sources projects (American and European), nuclear physics, etc. With newly proposed accelerator applications such as nuclear waste transmutation, replacement of nuclear power plants and others. Reliability has now become a number one priority for accelerator designers. Every part of an accelerator facility from cryogenic systems to data storage via RF systems are concerned by reliability. This aspect is now taken into account in the design/budget phase, especially for projects whose goal is to reach no more than 10 interruptions per year. This document gathers the slides but not the proceedings of the workshop.

  6. Accelerator reliability workshop

    International Nuclear Information System (INIS)

    Hardy, L.; Duru, Ph.; Koch, J.M.; Revol, J.L.; Van Vaerenbergh, P.; Volpe, A.M.; Clugnet, K.; Dely, A.; Goodhew, D.

    2002-01-01

    About 80 experts attended this workshop, which brought together all accelerator communities: accelerator driven systems, X-ray sources, medical and industrial accelerators, spallation sources projects (American and European), nuclear physics, etc. With newly proposed accelerator applications such as nuclear waste transmutation, replacement of nuclear power plants and others. Reliability has now become a number one priority for accelerator designers. Every part of an accelerator facility from cryogenic systems to data storage via RF systems are concerned by reliability. This aspect is now taken into account in the design/budget phase, especially for projects whose goal is to reach no more than 10 interruptions per year. This document gathers the slides but not the proceedings of the workshop

  7. Acceleration of radioactive ions

    International Nuclear Information System (INIS)

    Laxdal, R.E.

    2003-01-01

    There is an intense interest world-wide in the use of radioactive ion beams (RIBs) for experiment. In many existing or proposed facilities ions are produced or collected at source potential, ionized and re-accelerated. Within the past year three new ISOL based facilities have added dedicated post-accelerators to deliver accelerated RIBs to experiment. The paper gives an overview of RIB accelerators present and future, and explores the inherent features in the various acceleration methods with an emphasis on heavy ion linacs. The ISAC-I and ISAC-II post-accelerators are discussed as examples. Commissioning results and initial operating experience with ISAC-I will be presented

  8. Nuclear physics accelerator facilities

    International Nuclear Information System (INIS)

    1988-12-01

    This paper describes many of the nuclear physics heavy-ion accelerator facilities in the US and the research programs being conducted. The accelerators described are: Argonne National Laboratory--ATLAS; Brookhaven National Laboratory--Tandem/AGS Heavy Ion Facility; Brookhaven National Laboratory--Relativistic Heavy Ion Collider (RHIC) (Proposed); Continuous Electron Beam Accelerator Facility; Lawrence Berkeley Laboratory--Bevalac; Lawrence Berkeley Laboratory--88-Inch Cyclotron; Los Alamos National Laboratory--Clinton P. Anderson Meson Physics Facility (LAMPF); Massachusetts Institute of Technology--Bates Linear Accelerator Center; Oak Ridge National Laboratory--Holifield Heavy Ion Research Facility; Oak Ridge National Laboratory--Oak Ridge Electron Linear Accelerator; Stanford Linear Accelerator Center--Nuclear Physics Injector; Texas AandM University--Texas AandM Cyclotron; Triangle Universities Nuclear Laboratory (TUNL); University of Washington--Tandem/Superconducting Booster; and Yale University--Tandem Van de Graaff

  9. Japan Accelerator Conference

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    At the international level, the high energy accelerator scene evolves rapidly and the International Conference on High Energy Accelerators is where its strong pulse can best be felt. This year, the Conference was held for the first time in Japan, with the 14th meeting in the series having been hosted in August by the Japanese KEK National Laboratory for High Energy Physics, Tsukuba. The venue was a recognition of the premier accelerator physics and technology status achieved by this diligent nation

  10. Accelerator shielding benchmark problems

    International Nuclear Information System (INIS)

    Hirayama, H.; Ban, S.; Nakamura, T.

    1993-01-01

    Accelerator shielding benchmark problems prepared by Working Group of Accelerator Shielding in the Research Committee on Radiation Behavior in the Atomic Energy Society of Japan were compiled by Radiation Safety Control Center of National Laboratory for High Energy Physics. Twenty-five accelerator shielding benchmark problems are presented for evaluating the calculational algorithm, the accuracy of computer codes and the nuclear data used in codes. (author)

  11. Plasma particle accelerators

    International Nuclear Information System (INIS)

    Dawson, J.M.

    1988-01-01

    The Superconducting Supercollider (SSC) will require an 87-kilometer accelerator ring to boost particles to 40 TeV. The SSC's size is due in part to the fact that its operating principle is the same one that has dominated accelerator design for 50 years: it guides particles by means of magnetic fields and propels them by strong electric fields. If one were to build an equally powerful but smaller accelerator, one would need to increase the strength of the guiding and propelling fields. Actually, however, conventional technology may not be able to provide significant increases in field strength. There are two reasons. First, the forces from magnetic fields are becoming greater than the structural forces that hold a magnetic material together; the magnets that produce these fields would themselves be torn apart. Second, the energy from electric fields is reaching the energies that bind electrons to atoms; it would tear electrons from nuclei in the accelerator's support structures. It is the electric field problem that plasma accelerators can overcome. Plasma particle accelerators are based on the principle that particles can be accelerated by the electric fields generated within a plasma. Because the plasma has already been ionized, plasma particle accelerators are not susceptible to electron dissociation. They can in theory sustain accelerating fields thousands of times stronger that conventional technologies. So far two methods for creating plasma waves for accelerators have been proposed and tested: the wakefield and the beat wave. Although promising electric fields have been produced, more research is necessary to determine whether plasma particle accelerators can compete with the existing accelerators. 7 figs

  12. Wake field accelerators

    International Nuclear Information System (INIS)

    Wilson, P.B.

    1986-02-01

    In a wake field accelerator a high current driving bunch injected into a structure or plasma produces intense induced fields, which are in turn used to accelerate a trailing charge or bunch. The basic concepts of wake field acceleration are described. Wake potentials for closed cavities and periodic structures are derived, as are wake potentials on a collinear path with a charge distribution. Cylindrically symmetric structures excited by a beam in the form of a ring are considered

  13. CONFERENCE: Computers and accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1984-01-15

    In September of last year a Conference on 'Computers in Accelerator Design and Operation' was held in West Berlin attracting some 160 specialists including many from outside Europe. It was a Europhysics Conference, organized by the Hahn-Meitner Institute with Roman Zelazny as Conference Chairman, postponed from an earlier intended venue in Warsaw. The aim was to bring together specialists in the fields of accelerator design, computer control and accelerator operation.

  14. Japan Accelerator Conference

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1989-11-15

    At the international level, the high energy accelerator scene evolves rapidly and the International Conference on High Energy Accelerators is where its strong pulse can best be felt. This year, the Conference was held for the first time in Japan, with the 14th meeting in the series having been hosted in August by the Japanese KEK National Laboratory for High Energy Physics, Tsukuba. The venue was a recognition of the premier accelerator physics and technology status achieved by this diligent nation.

  15. CERN Accelerator School

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    The CERN Accelerator School (CAS) recently held its Advanced Accelerator Physics course in Greece on the island of Rhodes. Complementing the general course in Finland last year, this course was organized together with the University of Athens and NCSR. Demokritos. Accelerator specialists from Europe, CIS, Japan and USA followed two weeks of ''state-of-theart'' lectures designed to complete their education in the field

  16. Applying the accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Barbalat, Oscar

    1989-12-15

    Originally developed as tools for frontier physics, particle accelerators provide valuable spinoff benefits in applied research and technology. These accelerator applications are the subject of a biennial meeting in Denton, Texas, but the increasing activity in this field resulted this year (5-9 September) in the first European Conference on Accelerators in Applied Research and Technology, organized by K. Bethge of Frankfurt's Goethe University. The meeting reflected a wide range of applications - ion beam analysis, exploitation of nuclear microbeams, accelerator mass spectrometry, applications of photonuclear reactions, ion beam processing, synchrotron radiation for semiconductor technology, specialized technology.

  17. Laser-driven accelerators

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    Several devices for using laser fields have been proposed and they can be classified in three broad categories - 'far-field' accelerators (such as the principle of inverse free electron lasers), 'media' accelerators (which, for example, use the inverse Cherenkov effect or laser-controlled plasma waves), and 'near-field' accelerators (using a loaded guiding structure such as cavities or gratings). These different approaches come from the fact that a particle cannot be accelerated by the absorption of single photons (because of momentum conservation) and thus some other element has to intervene. (orig./HSI).

  18. Illinois Accelerator Research Center

    Science.gov (United States)

    Kroc, Thomas K.; Cooper, Charlie A.

    The Illinois Accelerator Research Center (IARC) hosts a new accelerator development program at Fermi National Accelerator Laboratory. IARC provides access to Fermi's state-of-the-art facilities and technologies for research, development and industrialization of particle accelerator technology. In addition to facilitating access to available existing Fermi infrastructure, the IARC Campus has a dedicated 36,000 ft2 Heavy Assembly Building (HAB) with all the infrastructure needed to develop, commission and operate new accelerators. Connected to the HAB is a 47,000 ft2 Office, Technology and Engineering (OTE) building, paid for by the state, that has office, meeting, and light technical space. The OTE building, which contains the Accelerator Physics Center, and nearby Accelerator and Technical divisions provide IARC collaborators with unique access to world class expertise in a wide array of accelerator technologies. At IARC scientists and engineers from Fermilab and academia work side by side with industrial partners to develop breakthroughs in accelerator science and translate them into applications for the nation's health, wealth and security.

  19. High Gradient Accelerator Research

    International Nuclear Information System (INIS)

    Temkin, Richard

    2016-01-01

    The goal of the MIT program of research on high gradient acceleration is the development of advanced acceleration concepts that lead to a practical and affordable next generation linear collider at the TeV energy level. Other applications, which are more near-term, include accelerators for materials processing; medicine; defense; mining; security; and inspection. The specific goals of the MIT program are: • Pioneering theoretical research on advanced structures for high gradient acceleration, including photonic structures and metamaterial structures; evaluation of the wakefields in these advanced structures • Experimental research to demonstrate the properties of advanced structures both in low-power microwave cold test and high-power, high-gradient test at megawatt power levels • Experimental research on microwave breakdown at high gradient including studies of breakdown phenomena induced by RF electric fields and RF magnetic fields; development of new diagnostics of the breakdown process • Theoretical research on the physics and engineering features of RF vacuum breakdown • Maintaining and improving the Haimson / MIT 17 GHz accelerator, the highest frequency operational accelerator in the world, a unique facility for accelerator research • Providing the Haimson / MIT 17 GHz accelerator facility as a facility for outside users • Active participation in the US DOE program of High Gradient Collaboration, including joint work with SLAC and with Los Alamos National Laboratory; participation of MIT students in research at the national laboratories • Training the next generation of Ph. D. students in the field of accelerator physics.

  20. Interacting with accelerators

    International Nuclear Information System (INIS)

    Dasgupta, S.

    1994-01-01

    Accelerators are research machines which produce energetic particle beam for use as projectiles to effect nuclear reactions. These machines along with their services and facilities may occupy very large areas. The man-machine interface of accelerators has evolved with technological changes in the computer industry and may be partitioned into three phases. The present paper traces the evolution of man-machine interface from the earliest accelerators to the present computerized systems incorporated in modern accelerators. It also discusses the advantages of incorporating expert system technology for assisting operators. (author). 8 ref

  1. Accelerator-based BNCT.

    Science.gov (United States)

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

    2014-06-01

    The activity in accelerator development for accelerator-based BNCT (AB-BNCT) both worldwide and in Argentina is described. Projects in Russia, UK, Italy, Japan, Israel, and Argentina to develop AB-BNCT around different types of accelerators are briefly presented. In particular, the present status and recent progress of the Argentine project will be reviewed. The topics will cover: intense ion sources, accelerator tubes, transport of intense beams, beam diagnostics, the (9)Be(d,n) reaction as a possible neutron source, Beam Shaping Assemblies (BSA), a treatment room, and treatment planning in realistic cases. © 2013 Elsevier Ltd. All rights reserved.

  2. Applying the accelerator

    International Nuclear Information System (INIS)

    Barbalat, Oscar

    1989-01-01

    Originally developed as tools for frontier physics, particle accelerators provide valuable spinoff benefits in applied research and technology. These accelerator applications are the subject of a biennial meeting in Denton, Texas, but the increasing activity in this field resulted this year (5-9 September) in the first European Conference on Accelerators in Applied Research and Technology, organized by K. Bethge of Frankfurt's Goethe University. The meeting reflected a wide range of applications - ion beam analysis, exploitation of nuclear microbeams, accelerator mass spectrometry, applications of photonuclear reactions, ion beam processing, synchrotron radiation for semiconductor technology, specialized technology

  3. Superconducting linear accelerator cryostat

    International Nuclear Information System (INIS)

    Ben-Zvi, I.; Elkonin, B.V.; Sokolowski, J.S.

    1984-01-01

    A large vertical cryostat for a superconducting linear accelerator using quarter wave resonators has been developed. The essential technical details, operational experience and performance are described. (author)

  4. Accelerator Modeling with MATLAB Accelerator Toolbox

    International Nuclear Information System (INIS)

    2002-01-01

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

  5. Santa Fe Accelerator Conference

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    The 10th USA National Particle Accelerator Conference was hosted this year by the Los Alamos National Laboratory in Santa Fe from 21-23 March. It was a resounding success in emphasizing the ferment of activity in the accelerator field. About 900 people registered and about 500 papers were presented in invited and contributed talks and poster sessions

  6. Relativistic Shock Acceleration

    International Nuclear Information System (INIS)

    Duffy, P.; Downes, T.P.; Gallant, Y.A.; Kirk, J.G.

    1999-01-01

    In this paper we briefly review the basic theory of shock waves in relativistic hydrodynamics and magneto-hydrodynamics, emphasising some astrophysically interesting cases. We then present an overview of the theory of particle acceleration at such shocks describing the methods used to calculate the spectral indices of energetic particles. Recent results on acceleration at ultra-relativistic shocks are discussed. (author)

  7. CERN Accelerator School

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1986-01-15

    The CERN Accelerator School (CAS) offers a regular course on general accelerator physics. The first basic course was given in September 1984 at Orsay, France, and last September the advanced course was jointly organized by CAS, Oxford's Nuclear Physics Laboratory and the Rutherford Appleton Laboratory, and held at The Queen's College, Oxford.

  8. Accelerator for nuclear transmutation

    International Nuclear Information System (INIS)

    Schapira, J.P.

    1984-01-01

    A review on nuclear transmutation of radioactive wastes using particle accelerators is given. Technical feasibility, nuclear data, costs of various projects are discussed. It appears that one high energy accelerator (1500 MeV, 300 mA proton) could probably handle the amount of actinides generated by the actual French nuclear program [fr

  9. Diagnostics for induction accelerators

    International Nuclear Information System (INIS)

    Fessenden, T.J.

    1996-04-01

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

  10. Diagnostics for induction accelerators

    International Nuclear Information System (INIS)

    Fessenden, T.J.

    1997-01-01

    The induction accelerator was conceived by N. C. Christofilos and first realized as the Astron accelerator that operated at Lawrence Livermore National Laboratory (LLNL) from the early 1960s to the end of 1975. This accelerator generated electron beams at energies near 6 MeV with typical currents of 600 Amperes in 400-ns pulses. The Advanced Test Accelerator (ATA) built at Livermore close-quote s Site 300 produced 10,000-Ampere beams with pulse widths of 70 ns at energies approaching 50 MeV. Several other electron and ion induction accelerators have been fabricated at LLNL and Lawrence Berkeley National Laboratory (LBNL). This paper reviews the principal diagnostics developed through efforts by scientists at both laboratories for measuring the current, position, energy, and emittance of beams generated by these high-current, short-pulse accelerators. Many of these diagnostics are closely related to those developed for other accelerators. However, the very fast and intense current pulses often require special diagnostic techniques and considerations. The physics and design of the more unique diagnostics developed for electron induction accelerators are presented and discussed in detail. copyright 1997 American Institute of Physics

  11. Hamburg Accelerator Conference (2)

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Edmund J.N. [CERN Accelerator School (Switzerland)

    1992-11-15

    From 20-24 July, Hamburg welcomed the Fifteenth International Conference on High Energy Accelerators (HEACC). The HEACC Conference traditionally reviews the status of all major accelerator projects whether they are already running like clockwork, still in the construction phase, or waiting impatiently for financial approval.

  12. Charged particle accelerator

    International Nuclear Information System (INIS)

    Arakawa, Kazuo.

    1969-01-01

    An accelerator is disclosed having a device which permits the electrodes of an accelerator tube to be readily conditioned in an uncomplicated manner before commencing operation. In particle accelerators, it is necessary to condition the accelerator electrodes before a stable high voltage can be applied. Large current accelerators of the cockcroft-walton type require a complicated manual operation which entails applying to the electrodes a low voltage which is gradually increased to induce a vacuum discharge and then terminated. When the discharge attains an extremely low level, the voltage is again impressed and again raised to a high value in low current type accelerators, a high voltage power supply charges the electrodes once to induce discharge followed by reapplying the voltage when the vacuum discharge reaches a low level, according to which high voltage is automatically applied. This procedure, however, requires that the high voltage power supply be provided with a large internal resistance to limit the current to within several milliamps. The present invention connects a high voltage power supply and an accelerator tube through a discharge current limiting resistor wired in parallel with a switch. Initially, the switch is opened enabling the power supply to impress a voltage limited to a prescribed value by a suitably chosen resistor. Conditioning is effected by allowing the voltage between electrodes to increase and is followed by closing the switch through which high voltage is applied directly to the accelerator for operation. (K.J. Owens)

  13. Asia honours accelerator physicists

    CERN Multimedia

    2010-01-01

    "Steve Meyers of Cern and Jie Wei of Beijing's Tsinghua University are the first recipients of a new prize for particle physics. The pair were honoured for their contributions to numerous particle-accelerator projects - including Cern's Large Hadron Collider - by the Asian Committee for Future Accelerators (ACFA)..." (1 paragraph)

  14. Accelerators Beyond The Tevatron?

    Energy Technology Data Exchange (ETDEWEB)

    Lach, Joseph; /Fermilab

    2010-07-01

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

  15. CERN Accelerator School

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    The CERN Accelerator School (CAS) offers a regular course on general accelerator physics. The first basic course was given in September 1984 at Orsay, France, and last September the advanced course was jointly organized by CAS, Oxford's Nuclear Physics Laboratory and the Rutherford Appleton Laboratory, and held at The Queen's College, Oxford

  16. Thoughts on accelerator tubes

    International Nuclear Information System (INIS)

    Larson, J.D.

    1978-01-01

    A brief, subjective review is given of mechanisms that may be limiting electrostatic accelerator tubes to present levels of performance. Suggestions are made for attacking these limitations with the purpose of stimulating the thinking of designers and users of electrostatic accelerators

  17. KEK digital accelerator

    Directory of Open Access Journals (Sweden)

    T. Iwashita

    2011-07-01

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

  18. Thoughts of accelerator tubes

    International Nuclear Information System (INIS)

    Larson, J.D.

    1977-01-01

    A brief, subjective review is given of mechanisms that may be limiting electrostatic accelerator tubes to present levels of performance. Suggestions are made for attacking these limitations with the purpose of stimulating the thinking of designers and users of electrostatic accelerators

  19. Racetrack linear accelerators

    International Nuclear Information System (INIS)

    Rowe, C.H.; Wilton, M.S. de.

    1979-01-01

    An improved recirculating electron beam linear accelerator of the racetrack type is described. The system comprises a beam path of four straight legs with four Pretzel bending magnets at the end of each leg to direct the beam into the next leg of the beam path. At least one of the beam path legs includes a linear accelerator. (UK)

  20. Linear Accelerator (LINAC)

    Science.gov (United States)

    ... uses microwave technology (similar to that used for radar) to accelerate electrons in a part of the accelerator called the "wave guide," then allows ... risk of accidental exposure is extremely low. top of page This page was ... No Please type your comment or suggestion into the following text ...

  1. Hamburg Accelerator Conference (2)

    International Nuclear Information System (INIS)

    Wilson, Edmund J.N.

    1992-01-01

    From 20-24 July, Hamburg welcomed the Fifteenth International Conference on High Energy Accelerators (HEACC). The HEACC Conference traditionally reviews the status of all major accelerator projects whether they are already running like clockwork, still in the construction phase, or waiting impatiently for financial approval

  2. Optimization of accelerator control

    International Nuclear Information System (INIS)

    Vasiljev, N.D.; Mozin, I.V.; Shelekhov, V.A.; Efremov, D.V.

    1992-01-01

    Expensive exploitation of charged particle accelerators is inevitably concerned with requirements of effectively obtaining of the best characteristics of accelerated beams for physical experiments. One of these characteristics is intensity. Increase of intensity is hindered by a number of effects, concerned with the influence of the volume charge field on a particle motion dynamics in accelerator's chamber. However, ultimate intensity, determined by a volume charge, is almost not achieved for the most of the operating accelerators. This fact is caused by losses of particles during injection, at the initial stage of acceleration and during extraction. These losses are caused by deviations the optimal from real characteristics of the accelerating and magnetic system. This is due to a number of circumstances, including technological tolerances on structural elements of systems, influence of measuring and auxiliary equipment and beam consumers' installations, placed in the closed proximity to magnets, and instability in operation of technological systems of accelerator. Control task consists in compensation of deviations of characteristics of magnetic and electric fields by optimal selection of control actions. As for technical means, automatization of modern accelerators allows to solve optimal control problems in real time. Therefore, the report is devoted to optimal control methods and experimental results. (J.P.N.)

  3. Accelerator breeder concept

    International Nuclear Information System (INIS)

    Bartholomew, G.A.; Fraser, J.S.; Garvey, P.M.

    1978-10-01

    The principal components and functions of an accelerator breeder are described. The role of the accelerator breeder as a possible long-term fissile production support facility for CANDU (Canada Deuterium Uranium) thorium advanced fuel cycles and the Canadian research and development program leading to such a facility are outlined. (author)

  4. Semiconductor acceleration sensor

    Science.gov (United States)

    Ueyanagi, Katsumichi; Kobayashi, Mitsuo; Goto, Tomoaki

    1996-09-01

    This paper reports a practical semiconductor acceleration sensor especially suited for automotive air bag systems. The acceleration sensor includes four beams arranged in a swastika structure. Two piezoresistors are formed on each beam. These eight piezoresistors constitute a Wheatstone bridge. The swastika structure of the sensing elements, an upper glass plate and a lower glass plate exhibit the squeeze film effect which enhances air dumping, by which the constituent silicon is prevented from breakdown. The present acceleration sensor has the following features. The acceleration force component perpendicular to the sensing direction can be cancelled. The cross-axis sensitivity is less than 3 percent. And, the erroneous offset caused by the differences between the thermal expansion coefficients of the constituent materials can be canceled. The high aspect ratio configuration realized by plasma etching facilitates reducing the dimensions and improving the sensitivity of the acceleration sensor. The present acceleration sensor is 3.9 mm by 3.9 mm in area and 1.2 mm in thickness. The present acceleration sensor can measure from -50 to +50 G with sensitivity of 0.275 mV/G and with non-linearity of less than 1 percent. The acceleration sensor withstands shock of 3000 G.

  5. Molecular ion acceleration using tandem accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Yuichi; Mizuhashi, Kiyoshi; Tajima, Satoshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1996-12-01

    In TIARA compound beam radiation system, cluster beams have been produced using 3 MV tandem accelerator (9SDH-2) to supply them to various radiation on injection experiments. Till now, productions of C{sub 2-8}, Si{sub 2-4} and O{sub 2} and their accelerations up to 6 MeV have been succeeded. This study aimed at production and acceleration of B{sub 2-4} and LiF. Anion clusters were produced using the conventional ion source of cesium sputter type. The proportions of atoms, molecules and clusters elicited from the ion source were varied depending on the material`s properties and the operating conditions of ion source such as sample temperature, sputter voltage and the shape of sample. The anion clusters were accelerated toward the high voltage terminal in the center of tandem accelerator, leading to cations through losing their electrons by the collision to N{sub 2} gas in a charge conversion cell at the terminal. Positively charged cluster ions could be obtained by modulating the pressure of N{sub 2} gas. Thus, B{sub 2} (64 nA), B{sub 3} (4.4 nA) and B{sub 4} (2.7 nA) have been produced and their maximum survival probabilities were higher than those of carbon or silicon clusters. In addition, the relationship between beam current and gas pressure was investigated for Bn (n = 2-4) and LiF. (M.N.)

  6. Plasma based accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, Allen [Max-Planck-Institut fuer Physik, Muenchen (Germany)

    2015-05-01

    The concept of laser-induced plasma wakefields as a technique to accelerate charged particles was introduced 35 years ago as a means to go beyond the accelerating gradients possible with metallic cavities supporting radio frequency electromagnetic fields. Significant developments in laser technology have made possible the pulse intensity needed to realize this concept, and rapid progress is now underway in the realization of laser-driven plasma wakefield acceleration. It has also been realized that similar accelerating gradients can be produced by particle beams propagating in plasmas, and experimental programs have also been undertaken to study this possibility. Positive results have been achieved with electron-driven plasma wakefields, and a demonstration experiment with proton-driven wakefields is under construction at CERN. The concepts behind these different schemes and their pros and cons are described, as well as the experimental results achieved. An outlook for future practical uses of plasma based accelerators will also be given.

  7. TIARA electrostatic accelerator facility

    International Nuclear Information System (INIS)

    Tajima, Satoshi; Takada, Isao; Mizuhashi, Kiyoshi; Uno, Sadanori; Ohkoshi, Kiyonori; Nakajima, Yoshinori; Saitoh, Yuichi; Ishii, Yasuyuki; Kamiya, Tomihiro

    1996-07-01

    In order to promote the Advanced Radiation Technology Project, Japan Atomic Energy Research Institute constructed TIARA facility composed of four ion accelerators at Takasaki Radiation Chemistry Research Establishment for the period from 1988 to 1993. A 3MV tandem accelerator and an AVF cycrotron were completed in 1991 as the first phase of the construction, and a 3MV single-ended accelerator and a 400kV ion implanter were completed in 1993 as the second phase. Three electrostatic accelerators, the tandem, the single-ended and the implanter, were installed in the Multiple-beam facility of TIARA and have been operated for various experiments with using single, dual and triple beams without any serious trouble. This report describes the constructive works, machine performances, control systems, safety systems and accessory equipments of the electrostatic accelerators. (author)

  8. 2016 Accelerators meeting

    International Nuclear Information System (INIS)

    Spiro, Michel; Revol, Jean-Luc; Biarrotte, Jean-Luc; Napoly, Olivier; Jardin, Pascal; Chautard, Frederic; Thomas, Jean Charles; Petit, Eric

    2016-09-01

    The Accelerators meeting is organised every two years by the Accelerators division of the French Society of Physics (SFP). It brings together about 50 participants during a one-day meeting. The morning sessions are devoted to scientific presentations while the afternoon is dedicated to technical visits of facilities. This document brings together the available presentations (slides): 1 - Presentation of the Ganil - Grand accelerateur national d'ions lourds/Big national heavy-ion accelerator, Caen (Jardin, Pascal); 2 - Presentation of the Accelerators division of the French Society of Physics (Revol, Jean-Luc); 3 - Forward-looking and Prospective view (Napoly, Olivier); 4 - Accelerators at the National Institute of Nuclear and particle physics, situation, Forward-looking and Prospective view (Biarrotte, Jean-Luc); 5 - GANIL-SPIRAL2, missions and goals (Thomas, Jean Charles); 6 - The SPIRAL2 project (Petit, Eric)

  9. Collinear wake field acceleration

    International Nuclear Information System (INIS)

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

    1985-04-01

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

  10. Standing wave accelerating structures

    International Nuclear Information System (INIS)

    Zavadtsev, A.A.; Zverev, B.V.; Sobepin, N.P.

    1984-01-01

    Accelerating ELA structures are considered and chosen for applied purposes of special designation. Accelerating structures with the standing wave are considered most effective for small size ELA. Designs and results of experimental investigation of two new accelerating structures are described. These are structures of the ''ring'' type with a decreased number of excitinq oscillation types and strucuture with transverse rods with a twice smaller transverse size as compared with the biperiodical structure with internal connection resonators. The accelerating biperiodical structures of the conventional type by the fact that the whole structure is not a linear chain of connected resonators, but a ring one. Model tests have shown that the homogeneous structure with transverse rods (STR) at the frequency of 2.8 GHz in the regime of the standing wave has an effective shunt resistance equalling 23 MOhm/m. It is shown that the small transverse size of biperiodic STR makes its application in logging linear electron accelerators

  11. Analyzing radial acceleration with a smartphone acceleration sensor

    Science.gov (United States)

    Vogt, Patrik; Kuhn, Jochen

    2013-03-01

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

  12. Collective ion acceleration

    International Nuclear Information System (INIS)

    Godfrey, B.B.; Faehl, R.J.; Newberger, B.S.; Shanahan, W.R.; Thode, L.E.

    1977-01-01

    Progress achieved in the understanding and development of collective ion acceleration is presented. Extensive analytic and computational studies of slow cyclotron wave growth on an electron beam in a helix amplifier were performed. Research included precise determination of linear coupling between beam and helix, suppression of undesired transients and end effects, and two-dimensional simulations of wave growth in physically realizable systems. Electrostatic well depths produced exceed requirements for the Autoresonant Ion Acceleration feasibility experiment. Acceleration of test ions to modest energies in the troughs of such waves was also demonstrated. Smaller efforts were devoted to alternative acceleration mechanisms. Langmuir wave phase velocity in Converging Guide Acceleration was calculated as a function of the ratio of electron beam current to space-charge limiting current. A new collective acceleration approach, in which cyclotron wave phase velocity is varied by modulation of electron beam voltage, is proposed. Acceleration by traveling Virtual Cathode or Localized Pinch was considered, but appears less promising. In support of this research, fundamental investigations of beam propagation in evacuated waveguides, of nonneutral beam linear eigenmodes, and of beam stability were carried out. Several computer programs were developed or enhanced. Plans for future work are discussed

  13. Multicavity proton cyclotron accelerator

    Directory of Open Access Journals (Sweden)

    J. L. Hirshfield

    2002-08-01

    Full Text Available A mechanism for acceleration of protons is described, in which energy gain occurs near cyclotron resonance as protons drift through a sequence of rotating-mode TE_{111} cylindrical cavities in a strong nearly uniform axial magnetic field. Cavity resonance frequencies decrease in sequence from one another with a fixed frequency interval Δf between cavities, so that synchronism can be maintained between the rf fields and proton bunches injected at intervals of 1/Δf. An example is presented in which a 122 mA, 1 MeV proton beam is accelerated to 961 MeV using a cascade of eight cavities in an 8.1 T magnetic field, with the first cavity resonant at 120 MHz and with Δf=8 MHz. Average acceleration gradient exceeds 40 MV/m, average effective shunt impedance is 223 MΩ/m, but maximum surface field in the cavities does not exceed 7.2 MV/m. These features occur because protons make many orbital turns in each cavity and thus experience acceleration from each cavity field many times. Longitudinal and transverse stability appear to be intrinsic properties of the acceleration mechanism, and an example to illustrate this is presented. This acceleration concept could be developed into a proton accelerator for a high-power neutron spallation source, such as that required for transmutation of nuclear waste or driving a subcritical fission burner, provided a number of significant practical issues can be addressed.

  14. The miniature accelerator

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    The image that most people have of CERN is of its enormous accelerators and their capacity to accelerate particles to extremely high energies. But thanks to some cutting-edge studies on beam dynamics and radiofrequency technology, along with innovative construction techniques, teams at CERN have now created the first module of a brand-new accelerator, which will be just 2 metres long. The potential uses of this miniature accelerator will include deployment in hospitals for the production of medical isotopes and the treatment of cancer. It’s a real David-and-Goliath story.   Serge Mathot, in charge of the construction of the "mini-RFQ", pictured with the first of the four modules that will make up the miniature accelerator. The miniature accelerator consists of a radiofrequency quadrupole (RFQ), a component found at the start of all proton accelerator chains around the world, from the smallest to the largest. The LHC is designed to produce very high-intensity beams ...

  15. Large electrostatic accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Jones, C.M.

    1984-01-01

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

  16. Large electrostatic accelerators

    International Nuclear Information System (INIS)

    Jones, C.M.

    1984-01-01

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

  17. Superconductivity and future accelerators

    International Nuclear Information System (INIS)

    Danby, G.T.; Jackson, J.W.

    1963-01-01

    For 50 years particle accelerators employing accelerating cavities and deflecting magnets have been developed at a prodigious rate. New accelerator concepts and hardware ensembles have yielded great improvements in performance and GeV/$. The great idea for collective acceleration resulting from intense auxiliary charged-particle beams or laser light may or may not be just around the corner. In its absence, superconductivity (SC) applied both to rf cavities and to magnets opened up the potential for very large accelerators without excessive energy consumption and with other economies, even with the cw operation desirable for colliding beams. HEP has aggressively pioneered this new technology: the Fermilab single ring 1 TeV accelerator - 2 TeV collider is near the testing stage. Brookhaven National Laboratory's high luminosity pp 2 ring 800 GeV CBA collider is well into construction. Other types of superconducting projects are in the planning stage with much background R and D accomplished. The next generation of hadron colliders under discussion involves perhaps a 20 TeV ring (or rings) with 40 TeV CM energy. This is a very large machine: even if the highest practical field B approx. 10T is used, the radius is 10x that of the Fermilab accelerator. An extreme effort to get maximum GeV/$ may be crucial even for serious consideration of funding

  18. Accelerator programme at CAT

    International Nuclear Information System (INIS)

    Ramamurthi, S.S.

    1991-01-01

    The Accelerator Programme at the Centre for Advanced Technology (CAT), Indore, has very broad based concept under which all types of accelerators are to be taken up for design and fabrication. This centre will be housing a wide variety of accelerators to serve as a common facility for the universities, national laboratories in addition to laboratories under the Department of Atomic Energy. In the first phase of the programme, a series of electron accelerators are designed and fabricated. They are synchrotron radiation sources of 450 MeV (INDUS-I) and of 2 GeV (INDUS-II), microtron upto energy of 20 MeV, linear accelerator upto 20 MeV, and DC Accelerator for industrial irradiation upto 750 KeV and 20 KW. A proton accelerator of 300 MeV with 20 MeV linac injector is also designed. CAT is also developing a strong base for support technologies like ultra high vacuum, radio frequency and microwaves, DC pulsed and superconducting magnets, power supplies and controls etc. These technologies are very useful for other industrial applications also. To develop user groups to utilise INDUS-II synchrotron radiation source, a batch production of rotating Anode X-ray generators with power supplies has been initiated. So also, the sputter ion pumps, electron guns, turbo molecular pumps are brought into batch production. (author)

  19. New accelerator ideas

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    In the past, providing higher particle beam energies meant building bigger accelerators. It is now universally accepted that with the current generation of accelerator projects either under construction (such as LEP at CERN) or proposed (such as the Superconducting Super Collider in the US), conventional techniques are reaching their practical limit. With the growing awareness that progress in particle physics requires new methods to accelerate particles, workshops and study groups are being set up across the world to search for ideas for the machines of tomorrow

  20. The auroral electron accelerator

    International Nuclear Information System (INIS)

    Bryant, D.A.; Hall, D.S.

    1989-01-01

    A model of the auroral electron acceleration process is presented in which the electrons are accelerated resonantly by lower-hybrid waves. The essentially stochastic acceleration process is approximated for the purposes of computation by a deterministic model involving an empirically derived energy transfer function. The empirical function, which is consistent with all that is known of electron energization by lower-hybrid waves, allows many, possibly all, observed features of the electron distribution to be reproduced. It is suggested that the process occurs widely in both space and laboratory plasmas. (author)

  1. ACCELERATORS: School report

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1987-12-15

    The expanded 1987 US Particle Accelerator School, held at Fermilab from 20 July to 14 August, included two two-week sessions. In the first, 101 students covered three university-style courses, listed as upper-division University of Chicago physics, covering the fundamentals of particle beams, magnetic optics and acceleration; relativistic electronics; and high energy storage rings. The 180 participants in the second session profited from 24 short courses presented by experts and covering a wide variety of topics in the physics and technology of particle accelerators.

  2. Hadron accelerators in medicine

    International Nuclear Information System (INIS)

    Amaldi, U.

    1996-01-01

    The application of hadron accelerators (protons and light ions) in cancer therapy is discussed. After a brief introduction on the rationale for the use of heavy charged particles in radiation therapy, a discussion is given on accelerator technology and beam delivery systems. Next, existing and planned facilities are briefly reviewed. The Italian Hadron-therapy Project is then described in some detail, with reference ro both the National Centre for Oncological Hadron-therapy and the design of different types of compact proton accelerators aimed at introducing proton therapy in a large umber of hospitals. (author)

  3. Maximum Acceleration Recording Circuit

    Science.gov (United States)

    Bozeman, Richard J., Jr.

    1995-01-01

    Coarsely digitized maximum levels recorded in blown fuses. Circuit feeds power to accelerometer and makes nonvolatile record of maximum level to which output of accelerometer rises during measurement interval. In comparison with inertia-type single-preset-trip-point mechanical maximum-acceleration-recording devices, circuit weighs less, occupies less space, and records accelerations within narrower bands of uncertainty. In comparison with prior electronic data-acquisition systems designed for same purpose, circuit simpler, less bulky, consumes less power, costs and analysis of data recorded in magnetic or electronic memory devices. Circuit used, for example, to record accelerations to which commodities subjected during transportation on trucks.

  4. ACCELERATORS: School prizes

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    Dedicated to its goal of encouraging scientists and students to work in the field of particle accelerators, the US Particle Accelerator School (operating since 1981) has switched to a new format. Starting this year, it will offer in alternate years basic accelerator physics plus advanced subjects in both university and symposium styles over four weeks. Expanding the school from two to four weeks gives additional flexibility, and undergraduate participation should be encouraged by university credits being offered for particular courses. In the intervening years, the school will organize six-day topical courses

  5. Accelerator Toolbox for MATLAB

    International Nuclear Information System (INIS)

    Terebilo, Andrei

    2001-01-01

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

  6. RF linear accelerators

    CERN Document Server

    Wangler, Thomas P

    2008-01-01

    Thomas P. Wangler received his B.S. degree in physics from Michigan State University, and his Ph.D. degree in physics and astronomy from the University of Wisconsin. After postdoctoral appointments at the University of Wisconsin and Brookhaven National Laboratory, he joined the staff of Argonne National Laboratory in 1966, working in the fields of experimental high-energy physics and accelerator physics. He joined the Accelerator Technology Division at Los Alamos National Laboratory in 1979, where he specialized in high-current beam physics and linear accelerator design and technology. In 2007

  7. Auroral electron acceleration

    International Nuclear Information System (INIS)

    Bryant, D.A.

    1989-10-01

    Two theories of auroral electron acceleration are discussed. Part 1 examines the currently widely held view that the acceleration is an ordered process in a quasi-static electric field. It is suggested that, although there are many factors seeming to support this theory, the major qualifications and uncertainties that have been identified combine to cast serious doubt over its validity. Part 2 is devoted to a relatively new interpretation in terms of stochastic acceleration in turbulent electric fields. This second theory, which appears to account readily for most known features of the electron distribution function, is considered to provide a more promising approach to this central question in magnetospheric plasma physics. (author)

  8. New accelerator ideas

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1985-05-15

    In the past, providing higher particle beam energies meant building bigger accelerators. It is now universally accepted that with the current generation of accelerator projects either under construction (such as LEP at CERN) or proposed (such as the Superconducting Super Collider in the US), conventional techniques are reaching their practical limit. With the growing awareness that progress in particle physics requires new methods to accelerate particles, workshops and study groups are being set up across the world to search for ideas for the machines of tomorrow.

  9. Advanced Accelerator Concepts

    Science.gov (United States)

    Siemann, Robert

    1998-04-01

    Current particle accelerators rely on conventional or superconducting radio frequency cavities to accelerate beams of protons or electrons for nuclear and particle research and for medical and materials science studies. New methods for achieving larger accelerating gradients have been proposed and are being studied. These include the use of high power lasers, laser driven plasmas, wake fields generated by intense low energy beams, and millimeter wavelength EM structures. The studies to date, and the prospects for practical applications of these new ideas will be discussed.

  10. Accelerators Spanish steps

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    In September, the CERN Accelerator School (CAS) held its third General Accelerator Physics Course, the venue this time being Salamanca, the oldest university in Spain. Spain, which rejoined CERN in 1982, now has a vigorous and steadily growing high energy physics community making substantial contributions to physics detector development and successfully involving Spanish industry. However the embryonic accelerator community cannot yet generate an equivalent level of activity, and this important channel for introducing new high technology into industry has yet to be fully exploited

  11. Joint International Accelerator School

    CERN Multimedia

    CERN Accelerator School

    2014-01-01

    The CERN and US Particle Accelerator Schools recently organised a Joint International Accelerator School on Beam Loss and Accelerator Protection, held at the Hyatt Regency Hotel, Newport Beach, California, USA from 5-14 November 2014. This Joint School was the 13th in a series of such schools, which started in 1985 and also involves the accelerator communities in Japan and Russia.   Photo courtesy of Alfonse Pham, Michigan State University.   The school attracted 58 participants representing 22 different nationalities, with around half from Europe and the other half from Asia and the Americas. The programme comprised 26 lectures, each of 90 minutes, and 13 hours of case study. The students were given homework each day and had an opportunity to sit a final exam, which counted towards university credit. Feedback from the participants was extremely positive, praising the expertise and enthusiasm of the lecturers, as well as the high standard and quality of their lectures. Initial dis...

  12. Future accelerators: physics issues

    International Nuclear Information System (INIS)

    Bjorken, J.D.

    1977-11-01

    High energy physics of the future using future accelerators is discussed. The proposed machines and instruments, physics issues and opportunities including brief sketches of outstanding recent results, and the way the proposed machines address these issues are considered. 42 references

  13. Compact particle accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Elizondo-Decanini, Juan M.

    2017-08-29

    A compact particle accelerator having an input portion configured to receive power to produce particles for acceleration, where the input portion includes a switch, is provided. In a general embodiment, a vacuum tube receives particles produced from the input portion at a first end, and a plurality of wafer stacks are positioned serially along the vacuum tube. Each of the plurality of wafer stacks include a dielectric and metal-oxide pair, wherein each of the plurality of wafer stacks further accelerate the particles in the vacuum tube. A beam shaper coupled to a second end of the vacuum tube shapes the particles accelerated by the plurality of wafer stacks into a beam and an output portion outputs the beam.

  14. The accelerator breeder

    International Nuclear Information System (INIS)

    Johansson, E.

    1986-01-01

    Interactions of high-energy particles with atomic nuclei, in particular heavy ones, leads to a strong emission of neutrons. Preferably these high-energy particles are protons or deuterons obtained from a linear accelerator. The neutrons emitted are utilized in the conversion of U238 to Pu239 or of Th232 to U233. The above is the basis of the accelerator breeder, a concept studied abroad in many variants. No such breeder has, however, so far been built, but there exists vast practical experience on the neutron production and on the linear accelerator. Some of the variants mentioned are described in the report, after a presentation of general characteristics for the particle-nucleus interaction and for the linear accelerator. (author)

  15. Accelerate Water Quality Improvement

    Science.gov (United States)

    EPA is committed to accelerating water quality improvement and minimizing negative impacts to aquatic life from contaminants and other stressors in the Bay Delta Estuary by working with California Water Boards to strengthen water quality improvement plans.

  16. Rejuvenating CERN's Accelerators

    CERN Multimedia

    2004-01-01

    In the coming years and especially in 2005, CERN's accelerators are going to receive an extensive renovation programme to ensure they will perform reliably and effectively when the LHC comes into service.

  17. Wake field acceleration experiments

    International Nuclear Information System (INIS)

    Simpson, J.D.

    1988-01-01

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

  18. Accelerated test program

    Science.gov (United States)

    Ford, F. E.; Harkness, J. M.

    1977-01-01

    A brief discussion on the accelerated testing of batteries is given. The statistical analysis and the various aspects of the modeling that was done and the results attained from the model are also briefly discussed.

  19. SSC accelerator availability allocation

    International Nuclear Information System (INIS)

    Dixon, K.T.; Franciscovich, J.

    1991-03-01

    Superconducting Super Collider (SSC) operational availability is an area of major concern, judged by the Central Design Group to present such risk that use of modern engineering tools would be essential to program success. Experience has shown that as accelerator beam availability falls below about 80%, efficiency of physics experiments degrades rapidly due to inability to maintain adequate coincident accelerator and detector operation. For this reason, the SSC availability goal has been set at 80%, even though the Fermi National Accelerator Laboratory accelerator, with a fraction of the SSC's complexity, has only recently approached that level. This paper describes the allocation of the top-level goal to part-level reliability and maintainability requirements, and it gives the results of parameter sensitivity studies designed to help identify the best approach to achieve the needed system availability within funding and schedule constraints. 1 ref., 12 figs., 4 tabs

  20. IAE pulsed electrostatic accelerator

    International Nuclear Information System (INIS)

    Afanas'ev, V.P.; Ganzhelyuk, M.L.; Kozlov, L.D.; Koltypin, E.A.; Molchanov, Yu.D.; Otroshchenko, G.A.; Yan'kov, G.B.

    1976-01-01

    The modernized pulse electrostatic accelerator using the klystron ion grouping and the beam interruption system prior to acceleration is described. The accelerator is modernized in order to improve parameters of a current pulse and to decrease the background in the measurement room. The ion beam of needed dimensions is obtained with the help of a high-frequency source and a beam grouping and deflection system. The general view of the beam grouping and deflection system is shown. The ion beam forming process is considered in detail. The modernized electrostatic accelerator permits to obtain a pulse current with a pulse length of 1.5 ns and an amplitude of 1.5 - 2 μA. With the repetition frequency of 2 MHz, the average target current is about 6 μA

  1. Ionization front accelerator

    International Nuclear Information System (INIS)

    Olson, C.L.

    1975-01-01

    In a recently proposed linear collective accelerator, ions are accelerated in a steep, moving potential well created at the head of an intense relativistic electron beam. The steepness of the potential well and its motion are controlled by the external ionization of a suitable background gas. Calculations concerning optimum choices for the background gas and the ionization method are presented; a two-step photoionization process employing Cs vapor is proposed. In this process, a super-radiant light source is used to excite the gas, and a UV laser is used to photoionize the excited state. The appropriate line widths and coupled ionization growth rate equations are discussed. Parameter estimates are given for a feasibility experiment, for a 1 GeV proton accelerator, and for a heavy ion accelerator (50 MeV/nucleon uranium). (auth)

  2. HEAVY ION LINEAR ACCELERATOR

    Science.gov (United States)

    Van Atta, C.M.; Beringer, R.; Smith, L.

    1959-01-01

    A linear accelerator of heavy ions is described. The basic contributions of the invention consist of a method and apparatus for obtaining high energy particles of an element with an increased charge-to-mass ratio. The method comprises the steps of ionizing the atoms of an element, accelerating the resultant ions to an energy substantially equal to one Mev per nucleon, stripping orbital electrons from the accelerated ions by passing the ions through a curtain of elemental vapor disposed transversely of the path of the ions to provide a second charge-to-mass ratio, and finally accelerating the resultant stripped ions to a final energy of at least ten Mev per nucleon.

  3. Advances in electrostatic accelerators

    International Nuclear Information System (INIS)

    Wegner, H.E.

    1975-01-01

    Advances in the design and performance of electrostatic accelerators since 1969 are reviewed with special emphasis on the ''forefront'' accelerators that are currently leading in voltage capability. A comparison of the acceleration tube design offered by the National Electrostatics Corporation and the High Voltage Engineering Corporation is also made. Other methods of increasing heavy ion energy by means of dual foil stripping are discussed as well as the performance of a newly developed sputter ion source for the production of negative heavy ions with reliability and flexibility that greatly exceeds all other present systems. Finally, new developments in terms of both booster systems and very high voltage electrostatic accelerators (25 to 60 MV) are discussed. (U.S.)

  4. Iteration and accelerator dynamics

    International Nuclear Information System (INIS)

    Peggs, S.

    1987-10-01

    Four examples of iteration in accelerator dynamics are studied in this paper. The first three show how iterations of the simplest maps reproduce most of the significant nonlinear behavior in real accelerators. Each of these examples can be easily reproduced by the reader, at the minimal cost of writing only 20 or 40 lines of code. The fourth example outlines a general way to iteratively solve nonlinear difference equations, analytically or numerically

  5. High energy medical accelerators

    International Nuclear Information System (INIS)

    Mandrillon, P.

    1990-01-01

    The treatment of tumours with charged particles, ranging from protons to 'light ions' (carbon, oxygen, neon), has many advantages, but up to now has been little used because of the absence of facilities. After the successful pioneering work carried out with accelerators built for physics research, machines dedicated to this new radiotherapy are planned or already in construction. These high energy medical accelerators are presented in this paper. (author) 15 refs.; 14 figs.; 8 tabs

  6. Vancouver Accelerator Conference

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1985-06-15

    Anyone who contends that particle physics is conducted in an ivory tower, not contributing to other fields of science or to humanity at large, should have attended the 1985 Particle Accelerator Conference in Vancouver. Over a thousand participants contributed 781 papers and only a fraction were actually related to accelerators for high energy physics. The majority of present developments are in the service of other fields of science, for alternative power sources, for medicine, for industrial applications, etc.

  7. A symmetrical rail accelerator

    International Nuclear Information System (INIS)

    Igenbergs, E.

    1991-01-01

    This paper reports on the symmetrical rail accelerator that has four rails, which are arranged symmetrically around the bore. The opposite rails have the same polarity and the adjacent rails the opposite polarity. In this configuration the radial force acting upon the individual rails is significantly smaller than in a conventional 2-rail configuration and a plasma armature is focussed towards the axis of the barrel. Experimental results indicate a higher efficiency compared to a conventional rail accelerator

  8. Ion optics for accelerators

    International Nuclear Information System (INIS)

    Enge, H.A.

    1974-01-01

    A review is given of ion-optic devices used in particle accelerators, including electrostatic lenses, magnetic quadrupoles, and deflecting magnets. Tube focusing in dc accelerators is also treated, and a novel scheme for shaping the electrodes to produce strong focusing is described. The concepts of emittance (phase space) and emittance conservation are briefly discussed. Chromatic and spatial aberrations are introduced, and it is shown how they can be calculated and sometimes substantially reduced. Some examples are given

  9. An active particle accelerator

    International Nuclear Information System (INIS)

    Goldman, T.

    1991-01-01

    Although a static charge is difficult to maintain on macroscopic particles, it is straightforward to construct a small object with a regularly oscillating electric dipole moment. For objects of a given size, one may then construct an accelerator by appropriately matching the frequency and separations of an external array of electrodes to this size. Physically feasible size ranges, an accelerator design, and possible applications of such systems are discussed. 8 refs., 9 figs

  10. Vancouver Accelerator Conference

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    Anyone who contends that particle physics is conducted in an ivory tower, not contributing to other fields of science or to humanity at large, should have attended the 1985 Particle Accelerator Conference in Vancouver. Over a thousand participants contributed 781 papers and only a fraction were actually related to accelerators for high energy physics. The majority of present developments are in the service of other fields of science, for alternative power sources, for medicine, for industrial applications, etc

  11. Collective field accelerator

    International Nuclear Information System (INIS)

    Luce, J.S.

    1978-01-01

    A collective field accelerator which operates with a vacuum diode and utilizes a grooved cathode and a dielectric anode that operates with a relativistic electron beam with a ν/γ of approx. 1, and a plurality of dielectric lenses having an axial magnetic field thereabout to focus the collectively accelerated electrons and ions which are ejected from the anode. The anode and lenses operate as unoptimized r-f cavities which modulate and focus the beam

  12. JAERI 20 MV tandem accelerator

    International Nuclear Information System (INIS)

    Tsukada, Kineo; Harada, Kichinosuke

    1977-01-01

    Accelerators have been developed as the experimental apparatuses for the studies on nuclei and elementary particles. One direction of the development is the acceleration of protons and electrons to more and more high energy, and another direction is the acceleration of heavy ions up to uranium to several MeV up to several hundreds MeV. However recently, accelerators are used as the useful tools for the studies in wider fields. There are electrostatic acceleration and high frequency acceleration in ion acceleration, and at present, super-large accelerators are high frequency acceleration type. In Japan Atomic Energy Research Institute, it was decided in 1975 to construct an electrostatic accelerator of tandem type in order to accelerate heavy ions. In case of the electrostatic acceleration, the construction is relatively simple, the acceleration of heavy ions is easy, the property of the ion beam is very good, and the energy is stable. Especially, the tandem type is convenient for obtaining high energy. The tandem accelerator of 20 MV terminal voltage was ordered from the National Electrostatics Corp., USA, and is expected to be completed in 1978. The significance of heavy ion acceleration in the development and research of atomic energy, tandem van de Graaff accelerators, the JAERI 20MV tandem accelerator, and the research project with this accelerator are described. (Kako, I.)

  13. APT accelerator technology

    International Nuclear Information System (INIS)

    Schneider, J. David

    1996-01-01

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

  14. Laser wakefield acceleration

    International Nuclear Information System (INIS)

    Esarey, E.; Ting, A.; Sprangle, P.

    1989-01-01

    The laser wakefield accelerator (LWFA) is a novel plasma based electron acceleration scheme which utilizes a relativistic optical guiding mechanism for laser pulse propagation. In the LWFA, a short, high power, single frequency laser pulse is propagated through a plasma. As the laser pulse propagates, its radial and axial ponderomotive forces nonresonantly generate large amplitude plasma waves (wakefields) with a phase velocity equal to the group velocity of the pulse. A properly phased electron bunch may then be accelerated by the axial wakefield and focused by the transverse wakefield. Optical guiding of the laser pulse in the plasma is necessary in order to achieve high energies in a single stage of acceleration. At sufficiently high laser powers, optical guiding may be achieved through relativistic effects associated with the plasma electrons. Preliminary analysis indicates that this scheme may overcome some of the difficulties present in the plasma beat wave accelerator and in the plasma wakefield accelerator. Analytical and numerical calculations are presented which study both laser pulse propagation within a plasma as well as the subsequent generation of large amplitude plasma waves. In addition, the generation of large amplitude plasma waves in regimes where the plasma waves become highly nonlinear is examined

  15. Photon acceleration in laser wakefield accelerators

    International Nuclear Information System (INIS)

    Trines, R. M. G. M.

    2007-01-01

    If the index of a refraction of a dispersive medium, such as a plasma, changes in time, it can be used to change the frequency of light propagating through the medium. This effect is called photon acceleration. It has been predicted in both theory and simulations, and also been demonstrated experimentally for the case of moving ionization fronts in gases (the so-called ionization blueshift) as well as for laser-driven wakefields.Here, we present studies of photon acceleration in laser-driven plasma wakefields. The unique spectral characteristics of this process will be discussed, to distinguish it from e.g. photon acceleration by ionization fronts, frequency domain interferometry or self-phase modulation. The dynamics of the photons in laser-wakefield interaction are studied through both regular particle-in-cell and wave-kinetic simulations. The latter approach provides a powerful, versatile, and easy-to-use method to track the propagation of individual spectral components, providing new insight into the physics of laser-plasma interaction. Theory, simulations and experimental results will be brought together to provide a full understanding of the dynamics of a laser pulse in its own wakefield.Even though the wave-kinetic approach mentioned above has mainly been developed for the description of laser-plasma interaction, it can be applied to a much wider range of fast wave-slow wave interaction processes: Langmuir waves-ion acoustic waves, drift waves-zonal flow, Rossby waves-zonal flow, or even photons-gravitational waves. Several recent results in these areas will be shown, often with surprising results

  16. Accelerator business in Japan expanding

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    Accelerators have become to be used increasingly in Japan in such fields as medicine, physics research and industry. This has caused stiff competition for market share by the manufacturers of accelerators. Electron beam accelerators for industrial use provide an indispensable means for adding values to products, for example, electric cables with incombustible insulators. Linear accelerators for the nondestructive inspection of nuclear components have been widely installed at equipment manufacturing plants. Active efforts have been exerted to develop small synchrotron radiation accelerators for next generation electronic industry. Cyclotrons for producing short life radioisotopes for medical diagnosis and electron beam accelerators for radiation therapy are also used routinely. The suppliers of accelerators include the companies manufacturing heavy electric machinery, heavy machinery and the engineering division of steelmakers. Accelerator physics is being formed, but universities do not yet offer the course regarding accelerators. Accelerator use in Japan and the trend of accelerator manufacturers are reported. (K.I.)

  17. Beam transport through electrostatic accelerators and matching into post accelerators

    International Nuclear Information System (INIS)

    Larson, J.D.

    1986-01-01

    Ion beam transport through electrostatic acceleration is briefly reviewed. Topics discussed include injection, matching into the low-energy acceleration stage, matching from the terminal stripper into the high-energy stage, transport to a post accelerator, space charge, bunching isochronism, dispersion and charge selection. Beam transport plans for the proposed Vivitron accelerator are described. (orig.)

  18. ORNL pellet acceleration program

    International Nuclear Information System (INIS)

    Foster, C.A.; Milora, S.L.

    1978-01-01

    The Oak Ridge National Laboratory (ORNL) pellet fueling program is centered around developing equipment to accelerate large pellets of solidified hydrogen to high speeds. This equipment will be used to experimentally determine pellet-plasma interaction physics on contemporary tokamaks. The pellet experiments performed on the Oak Ridge Tokamak (ORMAK) indicated that much larger, faster pellets would be advantageous. In order to produce and accelerate pellets of the order of 1 to 6 mm in diameter, two apparatuses have been designed and are being constructed. The first will make H 2 pellets by extruding a filament of hydrogen and mechanically chopping it into pellets. The pellets formed will be mechanically accelerated with a high speed arbor to a speed of 950 m/sec. This technique may be extended to speeds up to 5000 m/sec, which makes it a prime candidate for a reactor fueling device. In the second technique, a hydrogen pellet will be formed, loaded into a miniature rifle, and accelerated by means of high pressure hydrogen gas. This technique should be capable of speeds of the order of 1000 m/sec. While this technique does not offer the high performance of the mechanical accelerator, its relative simplicity makes it attractive for near-term experiments

  19. Accelerator development at Bates

    International Nuclear Information System (INIS)

    Sargent, C.P.

    1983-01-01

    The past year has seen the completion of a major expansion of the Bates Accelerator Laboratory. A second experimental hall, South Hall, and several magnetic spectrometers have been constructed. The accelerator's maximum energy has been raised from 400 to 750 MeV by means of beam recirculation. A current two-year project for the fabrication of an additional RF transmitter plus a 30% increase in RF peak power capability will increase energy further to ca. 1 GeV. During the same period pulse-to-pulse beam sharing between the high-resolution spectrometer area and South Hall will become available. In January 1981 the Laboratory submitted their ''Proposal for a Long-Range Expansion Program'' to DOE-NSF. The proposed development consists of three stages. Stage I calls for the addition of a pulse stretcher ring to furnish a CW beam to the South Hall beam lines. Additional experimental space for internal target experiments and photon tagging research are also included. Stage II increases the accelerator energy to 2.1 GeV (at 140 microamps) by means of a five-pass head-to-tail recirculator. Stage III is, at this time, a plan rather than a proposal. It increases accelerator energy to 4 GeV by extending the accelerator length and power and adds another pulse stretcher ring and three new experimental areas for the higher energy work. This paper discusses each of these stages in detail and recommends their funding and scheduling

  20. High energy plasma accelerators

    International Nuclear Information System (INIS)

    Tajima, T.

    1985-05-01

    Colinear intense laser beams ω 0 , kappa 0 and ω 1 , kappa 1 shone on a plasma with frequency separation equal to the electron plasma frequency ω/sub pe/ are capable of creating a coherent large longitudinal electric field E/sub L/ = mc ω/sub pe//e of the order of 1GeV/cm for a plasma density of 10 18 cm -3 through the laser beat excitation of plasma oscillations. Accompanying favorable and deleterious physical effects using this process for a high energy beat-wave accelerator are discussed: the longitudinal dephasing, pump depletion, the transverse laser diffraction, plasma turbulence effects, self-steepening, self-focusing, etc. The basic equation, the driven nonlinear Schroedinger equation, is derived to describe this system. Advanced accelerator concepts to overcome some of these problems are proposed, including the plasma fiber accelerator of various variations. An advanced laser architecture suitable for the beat-wave accelerator is suggested. Accelerator physics issues such as the luminosity are discussed. Applications of the present process to the current drive in a plasma and to the excitation of collective oscillations within nuclei are also discussed

  1. Linear induction accelerators

    International Nuclear Information System (INIS)

    Briggs, R.J.

    1986-06-01

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

  2. Accelerators for atomic energy research

    International Nuclear Information System (INIS)

    Shibata, Tokushi

    1999-01-01

    The research and educational activities accomplished using accelerators for atomic energy research were studied. The studied items are research subjects, facility operation, the number of master theses and doctor theses on atomic energy research using accelerators and the future role of accelerators in atomic energy research. The strategy for promotion of the accelerator facility for atomic energy research is discussed. (author)

  3. Accelerators in Science and Technology

    CERN Document Server

    Kailas, S

    2002-01-01

    Accelerators built for basic research in frontier areas of science have become important and inevitable tools in many areas of science and technology. Accelerators are examples of science driven high technology development. Accelerators are used for a wide ranging applications, besides basic research. Accelerator based multidisciplinary research holds great promise

  4. Plasma-based accelerator structures

    International Nuclear Information System (INIS)

    Schroeder, Carl B.

    1999-01-01

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

  5. Acceleration of magnetized plasma rings

    International Nuclear Information System (INIS)

    Hartman, D.; Eddleman, J.; Hammer, J.H.

    1982-01-01

    One scheme is considered, acceleration of a ring between coaxial electrodes by a B/sub theta/ field as in a coaxial rail-gun. If the electrodes are conical, a ring accelerated towards the apex of the cone undergoes self-similar compression (focussing) during acceleration. Because the allowable acceleration force F/sub a/ = kappa U/sub m//R (kappa - 2 , the accelerating distance for conical electrodes is considerably shortened over that required for coaxial electrodes. In either case however, since the accelerating flux can expand as the ring moves, most of the accelerating field energy can be converted into kinetic energy of the ring leading to high efficiency

  6. Need for accelerating electrons

    International Nuclear Information System (INIS)

    Kerst, D.W.

    1987-01-01

    Photons for nuclear disintegration experiments were not abundantly available in the early days of nuclear physics, whereas accelerated ions led the way. When electrons could be accelerated into the 20--30 MeV range, they found application not only to nuclear disintegration of the elements of the periodic table but also to x-ray radiography and to deep therapy. Energies of interest for probing nuclear structure by electron scattering and for meson production followed soon after. The elementary nature of the electron has now made it a valuable tool for present day particle physics; and the synchrotron radiation, which is an obstacle for some accelerating processes, has become a much sought after source of photons for experiments at atomic structure energies

  7. Artificial seismic acceleration

    Science.gov (United States)

    Felzer, Karen R.; Page, Morgan T.; Michael, Andrew J.

    2015-01-01

    In their 2013 paper, Bouchon, Durand, Marsan, Karabulut, 3 and Schmittbuhl (BDMKS) claim to see significant accelerating seismicity before M 6.5 interplate mainshocks, but not before intraplate mainshocks, reflecting a preparatory process before large events. We concur with the finding of BDMKS that their interplate dataset has significantly more fore- shocks than their intraplate dataset; however, we disagree that the foreshocks are predictive of large events in particular. Acceleration in stacked foreshock sequences has been seen before and has been explained by the cascade model, in which earthquakes occasionally trigger aftershocks larger than themselves4. In this model, the time lags between the smaller mainshocks and larger aftershocks follow the inverse power law common to all aftershock sequences, creating an apparent acceleration when stacked (see Supplementary Information).

  8. Superconducting Accelerator Magnets

    CERN Document Server

    Mess, K H; Wolff, S

    1996-01-01

    The main topic of the book are the superconducting dipole and quadrupole magnets needed in high-energy accelerators and storage rings for protons, antiprotons or heavy ions. The basic principles of low-temperature superconductivity are outlined with special emphasis on the effects which are relevant for accelerator magnets. Properties and fabrication methods of practical superconductors are described. Analytical methods for field calculation and multipole expansion are presented for coils without and with iron yoke. The effect of yoke saturation and geometric distortions on field quality is studied. Persistent magnetization currents in the superconductor and eddy currents the copper part of the cable are analyzed in detail and their influence on field quality and magnet performance is investigated. Superconductor stability, quench origins and propagation and magnet protection are addressed. Some important concepts of accelerator physics are introduced which are needed to appreciate the demanding requirements ...

  9. Incineration by accelerator

    International Nuclear Information System (INIS)

    Cribier, M.; FIoni, G.; Legrain, R.; Lelievre, F.; Leray, S.; Pluquet, A.; Safa, H.; Spiro, M.; Terrien, Y.; Veyssiere, Ch.

    1997-01-01

    The use MOX fuel allows to hope a stabilization of plutonium production around 500 tons for the French park. In return, the flow of minor actinides is increased to several tons. INCA (INCineration by Accelerator), dedicated instrument, would allow to transmute several tons of americium, curium and neptunium. It could be able to reduce nuclear waste in the case of stopping nuclear energy use. This project needs: a protons accelerator of 1 GeV at high intensity ( 50 m A), a window separating the accelerator vacuum from the reactor, a spallation target able to produce 30 neutrons by incident proton, an incineration volume where a part of fast neutrons around the target are recovered, and a thermal part in periphery with flows at 2.10 15 n/cm 2 .s; a chemical separation of elements burning in thermal (americium) from the elements needing a flow of fast neutrons. (N.C.)

  10. Universality of accelerating change

    Science.gov (United States)

    Eliazar, Iddo; Shlesinger, Michael F.

    2018-03-01

    On large time scales the progress of human technology follows an exponential growth trend that is termed accelerating change. The exponential growth trend is commonly considered to be the amalgamated effect of consecutive technology revolutions - where the progress carried in by each technology revolution follows an S-curve, and where the aging of each technology revolution drives humanity to push for the next technology revolution. Thus, as a collective, mankind is the 'intelligent designer' of accelerating change. In this paper we establish that the exponential growth trend - and only this trend - emerges universally, on large time scales, from systems that combine together two elements: randomness and amalgamation. Hence, the universal generation of accelerating change can be attained by systems with no 'intelligent designer'.

  11. Future accelerators in Japan

    International Nuclear Information System (INIS)

    Toge, Nobu

    1993-01-01

    This paper presents a brief report on the present status of future accelerator projects at the National Laboratory for High Energy Physics (KEK), Japan. The KEK laboratory has been successfully operating the TRISTAN accelerator complex since 1986. It consists of a 2.5 GeV electron/positron linac, an 8 GeV Accumulation Ring (AR) and a 29 GeV Main Ring (MR). Concurrently with this operation, in response to recommendations by the Japanese High Energy Physics Committee, survey studies have been continued on new accelerator facilities at KEK. They have two major future projects, namely, the asymmetric e + e - B-factory based on TRISTAN (TRISTAN-II) and the Japan Linear Collider (JLC). The purpose of this paper is to outline those research activities and to present an update on their status

  12. Medical uses of accelerators

    International Nuclear Information System (INIS)

    Bradbury, J.N.

    1981-01-01

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

  13. JKJ accelerator timing system

    International Nuclear Information System (INIS)

    Ohmori, C.; Mori, Y.; Yoshii, M.; Yamamoto, M.

    2001-01-01

    The JKJ (JAERl-KEK Joint Project) accelerator complex consists of the linear accelerator, 3 GeV and 50 GeV synchrotrons. To minimize the beam loss during the beam transfer from the 3 GeV synchrotron to the 50 GeV one, the synchronization of the two RF system of the rings is very important. To reduce the background from the high and low momentum neutron, the neutron beam chopper will be employed. The 3 GeV RF will be also synchronized to the chopper timing when the beam goes to the neutron facility. The whole timing control system of these accelerators and chopper will be described. (author)

  14. Accelerators for therapy

    International Nuclear Information System (INIS)

    Pohlit, W.

    1994-01-01

    In the past decades circular and linear electron accelerators have been developed for clinical use in radiation therapy of tumors with the aim of achieving a high radiation dose in the tumor and as low as possible dose in the adjacent normal tissues. Today about one thousand accelerators are in medical use throughout the world and many hundred thousand patients are treated every day with accelerator-produced radiation. There exists, however, a large number of patients who cannot be treated satisfactorily in this way. New types of radiations such as neutrons, negative pions, protons and heavy ions were therefore tested recently. The clinical experience with these radiations and with new types of treatment procedures indicate that in future the use of a scanning beam of high energy protons might be optimal for the treatment of tumors. (orig.)

  15. Superconducting accelerator magnet design

    International Nuclear Information System (INIS)

    Wolff, S.

    1994-01-01

    Superconducting dipoles, quadrupoles and correction magnets are necessary to achieve the high magnetic fields required for big accelerators presently in construction or in the design phase. Different designs of superconducting accelerator magnets are described and the designs chosen at the big accelerator laboratories are presented. The most frequently used cosθ coil configuration is discussed in detail. Approaches for calculating the magnetic field quality including coil end fields are presented. Design details of the cables, coils, mechanical structures, yokes, helium vessels and cryostats including thermal radiation shields and support structures used in superconducting magnets are given. Necessary material properties are mentioned. Finally, the main results of magnetic field measurements and quench statistics are presented. (orig.)

  16. Accelerator technology in tokamaks

    International Nuclear Information System (INIS)

    Kustom, R.L.

    1977-01-01

    This article presents the similarities in the technology required for high energy accelerators and tokamak fusion devices. The tokamak devices and R and D programs described in the text represent only a fraction of the total fusion program. The technological barriers to producing successful, economical tokamak fusion power plants are as many as the plasma physics problems to be overcome. With the present emphasis on energy problems in this country and elsewhere, it is very likely that fusion technology related R and D programs will vigorously continue; and since high energy accelerator technology has so much in common with fusion technology, more scientists from the accelerator community are likely to be attracted to fusion problems

  17. Accelerating the culture change!

    Science.gov (United States)

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

    1996-11-01

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

  18. Studies of accelerated compact toruses

    International Nuclear Information System (INIS)

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

    1983-01-01

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

  19. Microelectromechanical acceleration-sensing apparatus

    Science.gov (United States)

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

    2006-12-12

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

  20. CERN: Accelerator school

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Full text: Jyvaskyla, a university town in central Finland, was the setting for last year's General Accelerator School organized by the CERN Accelerator School. Well over a hundred students - more than for some time - followed two weeks of lectures on a broad spectrum of accelerator topics, the first step en route to becoming the designers, builders and operators of the surprisingly large number of, accelerators of all kinds either built or planned throughout Europe and further afield. This was the fifth such school organized by CAS in a biennial cycle which alternates this introductory level with more advanced tuition. The next, advanced, school will be from 20 October - 1 November, hosted by Athens University on the Greek Island of Rhodes. (Application details will become available in Spring but would-be participants should already reserve the dates.) After Finland, the CAS caravan moved to Benalmadena near Malaga in Spain where, together with Seville University, they organized one of the joint US-CERN schools held every two years and focusing on frontier accelerator topics. This time the subject was electron-positron factories - machines for high luminosity experiments in phi, tau-charm, beauty and Z physics. Experts from both sides of the Atlantic and from Japan shared their knowledge with an equally representative audience and probed the many intensity related phenomena which must be mastered to reach design performance. A number of these topics will receive extended coverage in the next specialist CAS School which is a repeat - by public demand - of the highly successful radiofrequency course held in Oxford in 1991. This school will be in Capri, Italy, with the support of the University of Naples from 29 April to 5 May. Details and application forms are now available by e-mail (CASRF@CERNVM.CERN.CH), by fax (+41 22 7824836) or from Suzanne von Wartburg, CERN Accelerator School, 1211 Geneva 23, Switzerland

  1. Interfacing to accelerator instrumentation

    International Nuclear Information System (INIS)

    Shea, T.J.

    1995-01-01

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

  2. Acceleration of polarized particles

    International Nuclear Information System (INIS)

    Buon, J.

    1992-05-01

    The spin kinetics of polarized beams in circular accelerators is reviewed in the case of spin-1/2 particles (electrons and protons) with emphasis on the depolarization phenomena. The acceleration of polarized proton beams in synchrotrons is described together with the cures applied to reduce depolarization, including the use of 'Siberian Snakes'. The in-situ polarization of electrons in storage rings due to synchrotron radiation is studied as well as depolarization in presence of ring imperfections. The applications of electron polarization to accurately calibrate the rings in energy and to use polarized beams in colliding-beam experiments are reviewed. (author) 76 refs., 19 figs., 1 tab

  3. Spallator - accelerator breeder

    International Nuclear Information System (INIS)

    Steinberg, M.

    1985-01-01

    The concept involves the use of spallation neutrons produced by interaction of a high energy proton (1 to 2 GeV) from a linear accelerator (LINAC) with a heavy metal target (uranium). The principal spallator concept is based on generating fissile fuel for use in LWR nuclear power plants. The spallator functions in conjunction with a reprocessing plant to regenerate and produce the Pu-239 or U-233 for fabrication into fresh LWR reactor fuel elements. Advances in proton accelerator technology has provided a solid base for predicting performance and optimizing the design of a reliable, continuous wave, high-current LINAC required by a fissile fuel production machine

  4. Accelerated cyclic corrosion tests

    Directory of Open Access Journals (Sweden)

    Prošek T.

    2016-06-01

    Full Text Available Accelerated corrosion testing is indispensable for material selection, quality control and both initial and residual life time prediction for bare and painted metallic, polymeric, adhesive and other materials in atmospheric exposure conditions. The best known Neutral Salt Spray (NSS test provides unrealistic conditions and poor correlation to exposures in atmosphere. Modern cyclic accelerated corrosion tests include intermittent salt spray, wet and dry phases and eventually other technical phases. They are able to predict the material performance in service more correctly as documented on several examples. The use of NSS should thus be restricted for quality control.

  5. Electrostatic accelerator dielectrics

    International Nuclear Information System (INIS)

    Cooke, C.M.

    1989-05-01

    High voltage insulation problems in electrostatic accelerators are discussed. The aim of the analysis is to broaden the knowledge, highlight the characteristics of insulation technology and design strategies to improve use. The basic geometry of the insulation in accelerators is considered. A detailed description of each of the insulation regions is provided. The gas gap insulation of the terminal voltage is found to be sensitive to regions of high electric stress. In order to obtain satisfactory performance from solid support insulation, the attention is focused on the electric stress value and distribution. Potential subjects for discussion and further investigations are given

  6. Remarks on stochastic acceleration

    International Nuclear Information System (INIS)

    Graeff, P.

    1982-12-01

    Stochastic acceleration and turbulent diffusion are strong turbulence problems since no expansion parameter exists. Hence the problem of finding rigorous results is of major interest both for checking approximations and for reference models. Since we have found a way of constructing such models in the turbulent diffusion case the question of the extension to stochastic acceleration now arises. The paper offers some possibilities illustrated by the case of 'stochastic free fall' which may be particularly interesting in the context of linear response theory. (orig.)

  7. Monoenergetic laser wakefield acceleration

    Directory of Open Access Journals (Sweden)

    N. E. Andreev

    2000-02-01

    Full Text Available Three dimensional test particle simulations are applied to optimization of the plasma-channeled laser wakefield accelerator (LWFA operating in a weakly nonlinear regime. Electron beam energy spread, emittance, and luminosity depend upon the proportion of the electron bunch size to the plasma wavelength. This proportion tends to improve with the laser wavelength increase. We simulate a prospective two-stage ∼1GeV LWFA with controlled energy spread and emittance. The input parameters correspond to realistic capabilities of the BNL Accelerator Test Facility that features a picosecond-terawatt CO_{2} laser and a high-brightness electron gun.

  8. High intensity hadron accelerators

    International Nuclear Information System (INIS)

    Teng, L.C.

    1989-05-01

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

  9. Photocathodes in accelerator applications

    International Nuclear Information System (INIS)

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

    1987-01-01

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

  10. "Light sail" acceleration reexamined.

    Science.gov (United States)

    Macchi, Andrea; Veghini, Silvia; Pegoraro, Francesco

    2009-08-21

    The dynamics of the acceleration of ultrathin foil targets by the radiation pressure of superintense, circularly polarized laser pulses is investigated by analytical modeling and particle-in-cell simulations. By addressing self-induced transparency and charge separation effects, it is shown that for "optimal" values of the foil thickness only a thin layer at the rear side is accelerated by radiation pressure. The simple "light sail" model gives a good estimate of the energy per nucleon, but overestimates the conversion efficiency of laser energy into monoenergetic ions.

  11. 'Light Sail' Acceleration Reexamined

    International Nuclear Information System (INIS)

    Macchi, Andrea; Veghini, Silvia; Pegoraro, Francesco

    2009-01-01

    The dynamics of the acceleration of ultrathin foil targets by the radiation pressure of superintense, circularly polarized laser pulses is investigated by analytical modeling and particle-in-cell simulations. By addressing self-induced transparency and charge separation effects, it is shown that for 'optimal' values of the foil thickness only a thin layer at the rear side is accelerated by radiation pressure. The simple 'light sail' model gives a good estimate of the energy per nucleon, but overestimates the conversion efficiency of laser energy into monoenergetic ions.

  12. Accelerating time to benefit

    DEFF Research Database (Denmark)

    Svejvig, Per; Geraldi, Joana; Grex, Sara

    Despite the ubiquitous pressure for speed, our approaches to accelerate projects remain constrained to the old-fashioned understanding of the project as a vehicle to deliver products and services, not value. This article explores an attempt to accelerate time to benefit. We describe and deconstruct...... of the time. Although all cases valued speed and speed to benefit, and implemented most practices proposed by the methodology, only three of the five projects were more successful in decreasing time to speed. Based on a multi-case study comparison between these five different projects and their respective...

  13. Plasma wave accelerator. II

    International Nuclear Information System (INIS)

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

    1982-01-01

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

  14. An accelerator technology legacy

    International Nuclear Information System (INIS)

    Heighway, E.A.

    1994-01-01

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

  15. Does one need a 4.5 K screen in cryostats of superconducting accelerator devices operating in superfluid helium? lessons from the LHL

    Science.gov (United States)

    Lebrun, Philippe; Parma, Vittorio; Tavian, Laurent

    2014-01-01

    Superfluid helium is increasingly used as a coolant for superconducting devices in particle accelerators: the lower temperature enhances the performance of superconductors in high-field magnets and reduces BCS losses in RF acceleration cavities, while the excellent transport properties of superfluid helium can be put to work in efficient distributed cooling systems. The thermodynamic penalty of operating at lower temperature however requires careful management of the heat loads, achieved inter alia through proper design and construction of the cryostats. A recurrent question appears to be that of the need and practical feasibility of an additional screen cooled by normal helium at around 4.5 K surrounding the cold mass at about 2 K, in such cryostats equipped with a standard 80 K screen. We introduce the issue in terms of first principles applied to the configuration of the cryostats, discuss technical constraints and economical limitations, and illustrate the argumentation with examples taken from large projects confronted with this issue, i.e. CEBAF, SPL, ESS, LHC, TESLA, European X-FEL, ILC.

  16. Accelerators in the sky

    International Nuclear Information System (INIS)

    Setti, G.

    1977-01-01

    The author surveys the large body of evidence showing that there are very efficient mechanisms capable of accelerating particles to high energies under very different astrophysical conditions. The circumstances whereby huge amounts of relativistic and ultrarelativistic particles such as one finds in a) cosmic rays, b) supernova remnants and c) radio galaxies and quasars are produced are considered. (Auth.)

  17. Heavy ion accelerator GANIL

    International Nuclear Information System (INIS)

    1975-04-01

    This article presents GANIL, a large national heavy ion accelerator. The broad problems of nuclear physics, atomic physics, astrophysics and physics of condensed media which can be approached and studied with this machine are discussed first, after which the final construction project is described. The project comprises a circular injector, a separated sector cyclotron up beam stripper, and a second separated cyclotron downstream [fr

  18. Accelerating with industry

    International Nuclear Information System (INIS)

    Southworth, Brian

    1992-01-01

    At the end of March, Berlin was the scene of the third biennial European Particle Accelerator Conference (EPAC). It carried the usual news from the front-line machines in the high energy physics Laboratories and reports on progress with the latest technologies

  19. Two-beam accelerator

    International Nuclear Information System (INIS)

    Sessler, A.M.; Hopkins, D.B.

    1986-06-01

    The Two-Beam Accelerator (TBA) consists of a long high-gradient accelerator structure (HGS) adjacent to an equal-length Free Electron Laser (FEL). In the FEL, a beam propagates through a long series of undulators. At regular intervals, waveguides couple microwave power out of the FEL into the HGS. To replenish energy given up by the FEL beam to the microwave field, induction accelerator units are placed periodically along the length of the FEL. In this manner it is expected to achieve gradients of more than 250 MV/m and thus have a serious option for a 1 TeV x 1 TeV linear collider. The state of present theoretical understanding of the TBA is presented with particular emphasis upon operation of the ''steady-state'' FEL, phase and amplitude control of the rf wave, and suppression of sideband instabilities. Experimental work has focused upon the development of a suitable HGS and the testing of this structure using the Electron Laser Facility (ELF). Description is given of a first test at ELF with a seven-cell 2π/3 mode structure which without preconditioning and with a not-very-good vacuum nevertheless at 35 GHz yielded an average accelerating gradient of 180 MV/m

  20. Hamburg Accelerator Conference

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Edmund J.N. [CERN Accelerator School (Switzerland)

    1992-10-15

    From 20-24 July, Hamburg welcomed the Fifteenth International Conference on High Energy Accelerators (HEACC). A natural highlight was the recent commissioning success of the HERA electron-proton collider at Hamburg's DESY Laboratory and its first high energy electron-proton collision data. This gave the meeting the feel of a family event celebrating a newborn.

  1. The Bevalac accelerator

    International Nuclear Information System (INIS)

    Dacal, A.

    1989-01-01

    Presented are the characteristics of the Bevatron and SuperHilac heavy ion accelerators in a very general manner. Some aspects of their application in the field of biological medicine and some of the interesting results obtained in experiments on nuclear physics are mentioned. (Author). 20 refs, 2 figs, 2 tabs

  2. Radioisotope Dating with Accelerators.

    Science.gov (United States)

    Muller, Richard A.

    1979-01-01

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

  3. The CERN accelerator complex

    CERN Multimedia

    Mobs, Esma Anais

    2016-01-01

    The LHC is the last ring (dark blue line) in a complex chain of particle accelerators. The smaller machines are used in a chain to help boost the particles to their final energies and provide beams to a whole set of smaller experiments, which also aim to uncover the mysteries of the Universe.

  4. The CERN accelerator complex

    CERN Multimedia

    Christiane Lefèvre

    2008-01-01

    The LHC is the last ring (dark grey line) in a complex chain of particle accelerators. The smaller machines are used in a chain to help boost the particles to their final energies and provide beams to a whole set of smaller experiments, which also aim to uncover the mysteries of the Universe.

  5. Prospects for Accelerator Technology

    Science.gov (United States)

    Todd, Alan

    2011-02-01

    Accelerator technology today is a greater than US$5 billion per annum business. Development of higher-performance technology with improved reliability that delivers reduced system size and life cycle cost is expected to significantly increase the total accelerator technology market and open up new application sales. Potential future directions are identified and pitfalls in new market penetration are considered. Both of the present big market segments, medical radiation therapy units and semiconductor ion implanters, are approaching the "maturity" phase of their product cycles, where incremental development rather than paradigm shifts is the norm, but they should continue to dominate commercial sales for some time. It is anticipated that large discovery-science accelerators will continue to provide a specialty market beset by the unpredictable cycles resulting from the scale of the projects themselves, coupled with external political and economic drivers. Although fraught with differing market entry difficulties, the security and environmental markets, together with new, as yet unrealized, industrial material processing applications, are expected to provide the bulk of future commercial accelerator technology growth.

  6. Ion sources for accelerators

    International Nuclear Information System (INIS)

    Alton, G.D.

    1974-01-01

    A limited review of low charge sate positive and negative ion sources suitable for accelerator use is given. A brief discussion is also given of the concepts underlying the formation and extraction of ion beams. Particular emphasis is placed on the technology of ion sources which use solid elemental or molecular compounds to produce vapor for the ionization process

  7. BNL accelerator plans

    International Nuclear Information System (INIS)

    Lowenstein, D.I.

    1986-01-01

    The Brookhaven National Laboratory plan for high energy and heavy ion physics accelerator use for the next ten-year period is described. The two major initiatives are in the construction of the Relativistic Heavy Ion Collider and the upgrade of the Alternating Gradient Synchrotron to a ''Mini Kaon Factory''

  8. The CERN Accelerator School

    CERN Multimedia

    2016-01-01

    Introduction to accelerator physics This course will take place in Budapest, Hungary, from 2 to 14 October 2016. It is now open for registration and further information can be found at: http://cas.web.cern.ch/cas/Hungary2016/Hungary-advert.html and http://indico.cern.ch/event/532397/.

  9. Accelerating with industry

    Energy Technology Data Exchange (ETDEWEB)

    Southworth, Brian

    1992-06-15

    At the end of March, Berlin was the scene of the third biennial European Particle Accelerator Conference (EPAC). It carried the usual news from the front-line machines in the high energy physics Laboratories and reports on progress with the latest technologies.

  10. Accelerating News Issue 5

    CERN Document Server

    Szeberenyi, A

    2013-01-01

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

  11. Next generation of accelerators

    International Nuclear Information System (INIS)

    Richter, B.

    1979-01-01

    Existing high-energy accelerators are reviewed, along with those under construction or being designed. Finally, some of the physics issues which go into setting machine parameters, and some of the features of the design of next generation electron and proton machines are discussed

  12. Cockroft Walton accelerator prototype

    International Nuclear Information System (INIS)

    Hutapea, Sumihar.

    1976-01-01

    Prototype of a Cockroft Walton generator using ceramic and plastic capacitors is discussed. Compared to the previous generator, the construction and components are much more improved. Pralon is used for the high voltage insulation column and plastic is used as a dielectric material for the high voltage capacitor. Cockroft Walton generator is used as a high tension supply for an accelerator. (author)

  13. Accelerated product development

    NARCIS (Netherlands)

    Langerak, F.; Seth, J.N.; Malhotra, N.K.

    2011-01-01

    Accelerated product development is a competitive strategy that seeks to reduce the development cycle time of new products. However, there has been little theoretical advancement and empirical model testing in the identification of the conditions under which cycle time reduction is appropriate, the

  14. The ATOMKI Accelerator Center

    International Nuclear Information System (INIS)

    Biri, S.; Kormany, Z.; Berzi, I.; Hunyadi, M.

    2009-01-01

    In 2009 a new division was established in our institute: the ATOMKI Accelerator Center (AAC). Before this time the facilities and staff of AAC belonged to other departments of the institute. The re-organization however, was necessary. It was understood that the translocation of all the accelerators into a centralized unit is advantageous in numerous fields. Here we just mention some of them. The submission of any instrumentation type proposal (EU or domestic) will be easier and has a higher chance to be supported. The organization and distribution of the beamtimes will be more equal and optimal. The usage of the maintenance and spare tools can became better and cheaper. The operating staff (cca. 20 person) can serve at more than one accelerator and the teams can help each other. The accelerator center actually became a fourth new basic unit of the institute besides the three traditional scientific divisions (see the Atomki homepage for the organization chart). The following six main facilities belong to the accelerator center: Cyclotron; VdG-5 accelerator; VdG-1 accelerator; ECR ion source; Isotope separator; Tandetron (under installation). In figure 1 the placements of these machines are shown in an artistic 3D map of the Atomki. The table 1 summarizes the main parameters of the accelerators. More detailed technical specification of the machines can be found in the new homepage of the center. In 2009 all the accelerators operated as scheduled, safely and without major breakdowns. After the experiences in the first months it can be concluded that the new center works well both for technical and human point of views. In the next sub-chapters the 2009 operation and development details of the individual accelerators are summarized. Cyclotron operation. The operation of the cyclotron in 2009 was concentrated to the usual 9 months; January, July and August were reserved for maintenance and holidays. The overall working time of the accelerator was 2009 hours; the time

  15. Wakeless triple soliton accelerator

    International Nuclear Information System (INIS)

    Mima, K.; Ohsuga, T.; Takabe, H.; Nishihara, K.; Tajima, T.; Zaidman, E.; Horton, W.

    1986-09-01

    We introduce and analyze the concept of a wakeless triple soliton accelerator in a plasma fiber. Under appropriate conditions the triple soliton with two electromagnetic and one electrostatic waves in the beat-wave resonance propagates with velocity c leaving no plasma wake behind, while the phase velocity of the electrostatic wave is made also c in the fiber

  16. Hamburg Accelerator Conference

    International Nuclear Information System (INIS)

    Wilson, Edmund J.N.

    1992-01-01

    From 20-24 July, Hamburg welcomed the Fifteenth International Conference on High Energy Accelerators (HEACC). A natural highlight was the recent commissioning success of the HERA electron-proton collider at Hamburg's DESY Laboratory and its first high energy electron-proton collision data. This gave the meeting the feel of a family event celebrating a newborn

  17. The CERN accelerator complex

    CERN Multimedia

    Haffner, Julie

    2013-01-01

    The LHC is the last ring (dark grey line) in a complex chain of particle accelerators. The smaller machines are used in a chain to help boost the particles to their final energies and provide beams to a whole set of smaller experiments, which also aim to uncover the mysteries of the Universe.

  18. Relativity and accelerator engineering

    International Nuclear Information System (INIS)

    Geloni, Gianluca; Kocharyan, Vitali; Saldin, Evgeni

    2017-09-01

    From a geometrical viewpoint, according to the theory of relativity, space and time constitute a four-dimensional continuum with pseudo-Euclidean structure. This has recently begun to be a practically important statement in accelerator physics. An X-ray Free Electron Laser (XFEL) is in fact the best, exciting example of an engineering system where improvements in accelerator technology makes it possible to develop ultrarelativistic macroscopic objects with an internal fine structure, and the theory of relativity plays an essential role in their description. An ultrarelativistic electron bunch modulated at nanometer-scale in XFELs has indeed a macroscopic finite-size of order of 10 μm. Its internal, collective structure is characterized in terms of a wave number vector. Here we will show that a four-dimensional geometrical approach, unusual in accelerator physics, is needed to solve problems involving the emission of radiation from an ultrarelativistic modulated electron beam accelerating along a curved trajectory. We will see that relativistic kinematics enters XFEL physics in a most fundamental way through the so-called Wigner rotation of the modulation wave number vector, which is closely associated to the relativity of simultaneity. If not taken into account, relativistic kinematics effects would lead to a strong qualitative disagreement between theory and experiments. In this paper, several examples of relativistic kinematics effects, which are important for current and future XFEL operation, are studied. The theory of relativity is applied by providing details of the clock synchronization procedure within the laboratory frame. This approach, exploited here but unusual in literature, is rather ''practical'', and should be acceptable to accelerator physicists.

  19. Menopause accelerates biological aging

    Science.gov (United States)

    Levine, Morgan E.; Lu, Ake T.; Chen, Brian H.; Hernandez, Dena G.; Singleton, Andrew B.; Ferrucci, Luigi; Bandinelli, Stefania; Salfati, Elias; Manson, JoAnn E.; Quach, Austin; Kusters, Cynthia D. J.; Kuh, Diana; Wong, Andrew; Teschendorff, Andrew E.; Widschwendter, Martin; Ritz, Beate R.; Absher, Devin; Assimes, Themistocles L.; Horvath, Steve

    2016-01-01

    Although epigenetic processes have been linked to aging and disease in other systems, it is not yet known whether they relate to reproductive aging. Recently, we developed a highly accurate epigenetic biomarker of age (known as the “epigenetic clock”), which is based on DNA methylation levels. Here we carry out an epigenetic clock analysis of blood, saliva, and buccal epithelium using data from four large studies: the Women's Health Initiative (n = 1,864); Invecchiare nel Chianti (n = 200); Parkinson's disease, Environment, and Genes (n = 256); and the United Kingdom Medical Research Council National Survey of Health and Development (n = 790). We find that increased epigenetic age acceleration in blood is significantly associated with earlier menopause (P = 0.00091), bilateral oophorectomy (P = 0.0018), and a longer time since menopause (P = 0.017). Conversely, epigenetic age acceleration in buccal epithelium and saliva do not relate to age at menopause; however, a higher epigenetic age in saliva is exhibited in women who undergo bilateral oophorectomy (P = 0.0079), while a lower epigenetic age in buccal epithelium was found for women who underwent menopausal hormone therapy (P = 0.00078). Using genetic data, we find evidence of coheritability between age at menopause and epigenetic age acceleration in blood. Using Mendelian randomization analysis, we find that two SNPs that are highly associated with age at menopause exhibit a significant association with epigenetic age acceleration. Overall, our Mendelian randomization approach and other lines of evidence suggest that menopause accelerates epigenetic aging of blood, but mechanistic studies will be needed to dissect cause-and-effect relationships further. PMID:27457926

  20. Relativity and accelerator engineering

    Energy Technology Data Exchange (ETDEWEB)

    Geloni, Gianluca [European XFEL GmbH, Schenefeld (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2017-09-15

    From a geometrical viewpoint, according to the theory of relativity, space and time constitute a four-dimensional continuum with pseudo-Euclidean structure. This has recently begun to be a practically important statement in accelerator physics. An X-ray Free Electron Laser (XFEL) is in fact the best, exciting example of an engineering system where improvements in accelerator technology makes it possible to develop ultrarelativistic macroscopic objects with an internal fine structure, and the theory of relativity plays an essential role in their description. An ultrarelativistic electron bunch modulated at nanometer-scale in XFELs has indeed a macroscopic finite-size of order of 10 μm. Its internal, collective structure is characterized in terms of a wave number vector. Here we will show that a four-dimensional geometrical approach, unusual in accelerator physics, is needed to solve problems involving the emission of radiation from an ultrarelativistic modulated electron beam accelerating along a curved trajectory. We will see that relativistic kinematics enters XFEL physics in a most fundamental way through the so-called Wigner rotation of the modulation wave number vector, which is closely associated to the relativity of simultaneity. If not taken into account, relativistic kinematics effects would lead to a strong qualitative disagreement between theory and experiments. In this paper, several examples of relativistic kinematics effects, which are important for current and future XFEL operation, are studied. The theory of relativity is applied by providing details of the clock synchronization procedure within the laboratory frame. This approach, exploited here but unusual in literature, is rather ''practical'', and should be acceptable to accelerator physicists.

  1. Acceleration of polarized proton beams

    International Nuclear Information System (INIS)

    Roser, T.

    1998-01-01

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

  2. Nonlinear dynamics in particle accelerators

    CERN Document Server

    Dilão, Rui

    1996-01-01

    This book is an introductory course to accelerator physics at the level of graduate students. It has been written for a large audience which includes users of accelerator facilities, accelerator physicists and engineers, and undergraduates aiming to learn the basic principles of construction, operation and applications of accelerators.The new concepts of dynamical systems developed in the last twenty years give the theoretical setting to analyse the stability of particle beams in accelerator. In this book a common language to both accelerator physics and dynamical systems is integrated and dev

  3. Unlimited Relativistic Shock Surfing Acceleration

    International Nuclear Information System (INIS)

    Ucer, D.; Shapiro, V. D.

    2001-01-01

    Nonrelativistic shock surfing acceleration at quasiperpendicular shocks is usually considered to be a preacceleration mechanism for slow pickup ions to initiate diffusive shock acceleration. In shock surfing, the particle accelerates along the shock front under the action of the convective electric field of the plasma flow. However, the particle also gains kinetic energy normal to the shock and eventually escapes downstream. We consider the case when ions are accelerated to relativistic velocities. In this case, the ions are likely to be trapped for infinitely long times, because the energy of bounce oscillations tends to decrease during acceleration. This suggests the possibility of unlimited acceleration by shock surfing

  4. Accelerator mass spectrometry at the Rossendorf 5 MV tandem accelerator

    International Nuclear Information System (INIS)

    Friedrich, M.; Buerger, W.; Curian, H.; Hartmann, B.; Hentschel, E.; Matthes, H.; Probst, W.; Seidel, M.; Turuc, S.; Hebert, D.; Rothe, T.; Stolz, W.

    1992-01-01

    The Rossendorf electrostatic accelerators (5 MV tandem accelerator and single ended 2 MV van de Graaff accelerator) are already used for ion beam analysis. The existing methods (RBS, PIXE, ERDA, NRA, nuclear microprobe and external beam) will be completed by introduction of Accelerator Mass Spectrometry (AMS). A short description of the Rossendorf AMS system is given and first experimental results are presented. (R.P.) 4 refs.; 6 figs

  5. SALOME: An Accelerator for the Practical Course in Accelerator Physics

    OpenAIRE

    Miltchev, Velizar; Riebesehl, Daniel; Roßbach, Jörg; Trunk, Maximilian; Stein, Oliver

    2014-01-01

    SALOME (Simple Accelerator for Learning Optics and the Manipulation of Electrons) is a short low energy linear electron accelerator built by the University of Hamburg. The goal of this project is to give the students the possibility to obtain hands-on experience with the basics of accelerator physics. In this contribution the layout of the device will be presented. The most important components of the accelerator will be discussed and an overview of the planned demonstration experiments will ...

  6. Mass spectrometry with accelerators.

    Science.gov (United States)

    Litherland, A E; Zhao, X-L; Kieser, W E

    2011-01-01

    As one in a series of articles on Canadian contributions to mass spectrometry, this review begins with an outline of the history of accelerator mass spectrometry (AMS), noting roles played by researchers at three Canadian AMS laboratories. After a description of the unique features of AMS, three examples, (14)C, (10)Be, and (129)I are given to illustrate the methods. The capabilities of mass spectrometry have been extended by the addition of atomic isobar selection, molecular isobar attenuation, further ion acceleration, followed by ion detection and ion identification at essentially zero dark current or ion flux. This has been accomplished by exploiting the techniques and accelerators of atomic and nuclear physics. In 1939, the first principles of AMS were established using a cyclotron. In 1977 the selection of isobars in the ion source was established when it was shown that the (14)N(-) ion was very unstable, or extremely difficult to create, making a tandem electrostatic accelerator highly suitable for assisting the mass spectrometric measurement of the rare long-lived radioactive isotope (14)C in the environment. This observation, together with the large attenuation of the molecular isobars (13)CH(-) and (12)CH 2(-) during tandem acceleration and the observed very low background contamination from the ion source, was found to facilitate the mass spectrometry of (14)C to at least a level of (14)C/C ~ 6 × 10(-16), the equivalent of a radiocarbon age of 60,000 years. Tandem Accelerator Mass Spectrometry, or AMS, has now made possible the accurate radiocarbon dating of milligram-sized carbon samples by ion counting as well as dating and tracing with many other long-lived radioactive isotopes such as (10)Be, (26)Al, (36)Cl, and (129)I. The difficulty of obtaining large anion currents with low electron affinities and the difficulties of isobar separation, especially for the heavier mass ions, has prompted the use of molecular anions and the search for alternative

  7. IFMIF accelerators design

    International Nuclear Information System (INIS)

    Mosnier, A.; Ratzinger, U.

    2008-01-01

    The IFMIF requirement for 250 mA current of deuteron beams at a nominal energy of 40 MeV is met by means of two identical continuous wave (CW) 175 MHz linear accelerators running in parallel, each delivering a 125 mA, 40 MeV deuteron beam to the common target. This approach allows to stay within the current capability of present RF linac technology while providing operational redundancy in case of failure of one of the linacs. Each linac comprises a sequence of acceleration and beam transport/matching stages. The ion source generates a 140 mA deuteron beam at 100 keV. A low energy beam transport (LEBT) transfers the deuteron beam from the source to a radio frequency quadrupole (RFQ) cavity. The RFQ bunches and accelerates the 125 mA beam to 5 MeV. The RFQ output beam is injected through a matching section into a drift-tube-linac (DTL) where it is accelerated to the final energy of 40 MeV. In the reference design, the final acceleration stage is a conventional Alvarez-type DTL with post-couplers operating at room temperature. Operation of both the RFQ and the DTL at the same relatively low frequency is essential for accelerating the high current deuteron beam with low beam loss. The primary concern of the IFMIF linacs is the minimization of beam losses, which could limit their availability and maintainability due to excessive activation of the linac and irradiation of the environment. A careful beam dynamics design is therefore needed from the source to the target to avoid the formation of particle halo that could finally be lost in the linac or transfer lines. A superconducting solution for the high energy portion of the linac using, for example, CH-structure or coaxial-type resonators, could offer some advantages, in particular the reduction of operational costs. Careful beam dynamics simulations and comparison tests with beam during the EVEDA phase are however necessary in order to fully assess the technical feasibility of such alternative solutions

  8. Recent progress in particle accelerators

    International Nuclear Information System (INIS)

    Cole, F.T.; Mills, F.E.

    1988-01-01

    Many accelerators have also been built for medical radiography and therapy. Electron accelerators for this application are available commercially, using the electrons directly or bremsstrahlung photons. Neutrons produced by accelerator beams have also been used for therapy with considerable success, and several proton accelerators built for physics research have been adapted for direct therapy with protons. The first proton accelerator specifically for therapy is now being built. Separate from what might be called conventional accelerator technology, an entirely new field utilizing very highly pulsed power has been developed, and beams of short pulses of thousands or millions of amperes peak current in the MeV energy range are now available. These beams have important applications in high-energy particle acceleration, controlled fusion, industrial treatment of materials, and possibly in food preservation. All of these accelerators make use of external fields of acceleration. There is also vigorous research into new methods of acceleration, in many schemes making use of the intense accelerating fields, generated by laser beams or by plasma states of matter. This research has not as yet made traditional kinds of accelerators outmoded, but many workers hope that early in the next century there will be practical new acceleration methods making use of these very high fields. These developments are discussed in detail

  9. Acceleration of 14C beams in electrostatic accelerators

    International Nuclear Information System (INIS)

    Rowton, L.J.; Tesmer, J.R.

    1981-01-01

    Operational problems in the production and acceleration of 14 C beams for nuclear structure research in Los Alamos National Laboratory's Van de Graaff accelerators are discussed. Methods for the control of contamination in ion sources, accelerators and personnel are described. Sputter source target fabrication techniques and the relative beam production efficiencies of various types of bound particulate carbon sputter source targets are presented

  10. Adaptive control for accelerators

    International Nuclear Information System (INIS)

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

    1991-01-01

    This patent describes 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

  11. Commissioning the GTA accelerator

    International Nuclear Information System (INIS)

    Sander, O.R.; Atkins, W.H.; Bolme, G.O.; Bowling, S.; Brown, S.; Cole, R.; Gilpatrick, J.D.; Garnett, R.; Guy, F.W.; Ingalls, W.B.; Johnson, K.F.; Kerstiens, D.; Little, C.; Lohsen, R.A.; Lloyd, S.; Lysenko, W.P.; Mottershead, C.T.; Neuschaefer, G.; Power, J.; Rusthoi, D.P.; Sandoval, D.P.; Stevens, R.R.; Vaughn, G.; Wadlinger, E.A.; Connolly, R.; Weiss, R.; Saadatmand, K.

    1992-01-01

    The Ground Test Accelerator (GTA) is being used to resolve the physics and engineering issues related to accelerating, focusing, and steering a high-brightness, high-current H - beam and then neutralizing it. The goal is to produce a 24 MeV, 50 mA device with a 2% duty factor. Specific features of the GTA -- injector, beam optics, rf linac structures, diagnostics, control and rf power systems are described. The first four steps in commissioning have been completed. The RFQ predicted and measured performances are in good agreement; however, the transmission is lower than specifications. Input emittance is larger than design specifications and increases the effects of image charge and multipoles. Displacement of steering magnets in either the horizontal or vertical plane caused beam displacements in both planes. It is suspected that quadrupole rotation is the cause of the coupled motion. 9 figs., 5 tabs., 11 refs

  12. Accelerator research studies

    International Nuclear Information System (INIS)

    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

  13. Adaptive control for accelerators

    Science.gov (United States)

    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.

  14. Accelerator research studies

    International Nuclear Information System (INIS)

    1990-01-01

    This progress report for the Accelerator Research Studies program at the University of Maryland covers the second year (June 1, 1989 to May 31, 1990) of the current three-year contract period from June 1, 1988 to May 31, 1991, funded by the Department of Energy under Contract No. AC05-85ER40216. The research program is divided into three separate tasks, as follows: the study of Transport and Longitudinal Compression of Intense, High-Brightness Beams; the study of Collective Ion Acceleration by Intense Electron Beams and Pulse-Powered Plasma Focus; the study of Microwave Sources and Parameter Scaling for High-Frequency Linacs. This report consists of three sections in which the progress for each task is documented separately. An introduction and synopsis is presented at the beginning of the progress report for each task

  15. Review of ion accelerators

    International Nuclear Information System (INIS)

    Alonso, J.

    1990-06-01

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

  16. Hardware Accelerated Simulated Radiography

    International Nuclear Information System (INIS)

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

    2005-01-01

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

  17. Review of accelerator instrumentation

    International Nuclear Information System (INIS)

    Pellegrin, J.L.

    1980-05-01

    Some of the problems associated with the monitoring of accelerator beams, particularly storage rings' beams, are reviewed along with their most common solutions. The various electrode structures used for the measurement of beam current, beam position, and the detection of the bunches' transverse oscillations, yield pulses with sub-nanosecond widths. The electronics for the processing of these short pulses involves wide band techniques and circuits usually not readily available from industry or the integrated circuit market: passive or active, successive integrations, linear gating, sample-and-hold circuits with nanosecond acquisition time, etc. This report also presents the work performed recently for monitoring the ultrashort beams of colliding linear accelerators or single-pass colliders. To minimize the beam emittance, the beam position must be measured with a high resolution, and digitized on a pulse-to-pulse basis. Experimental results obtained with the Stanford two-mile Linac single bunches are included

  18. Laser beam accelerator

    International Nuclear Information System (INIS)

    Tajima, T.; Dawson, J.M.

    1981-01-01

    Parallel intense photon (laser, microwave, etc.) beams /omega/sub //0, k/sub 0/ and /omega/sub //1, k/sub 1/ shone on a plasma with frequency separation equal to the plasma frequency /omega/sub //p is capable of accelerating plasma electrons to high energies in large flux. The photon beat excites through the forward Raman scattering large amplitude plasmons whose phase velocity is equal to (/omega/ /sub 0/-/omega/sub //1)/(k/sub 0/-k/sub 1/), close to c in an underdense plasma. The multiple forward Raman instability produces smaller and smaller frequency and group velocity of photons; thus the photons slow down in the plasma by emitting accelerated electrons (inverse Cherenkov process). 6 refs

  19. Commissioning the GTA accelerator

    International Nuclear Information System (INIS)

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

    1992-01-01

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

  20. accelerating cavity from LEP

    CERN Multimedia

    This is an accelerating cavity from LEP, with a layer of niobium on the inside. Operating at 4.2 degrees above absolute zero, the niobium is superconducting and carries an accelerating field of 6 million volts per metre with negligible losses. Each cavity has a surface of 6 m2. The niobium layer is only 1.2 microns thick, ten times thinner than a hair. Such a large area had never been coated to such a high accuracy. A speck of dust could ruin the performance of the whole cavity so the work had to be done in an extremely clean environment. These challenging requirements pushed European industry to new achievements. 256 of these cavities are now used in LEP to double the energy of the particle beams.

  1. Particle accelerator physics

    CERN Document Server

    Wiedemann, Helmut

    2015-01-01

    This book by Helmut Wiedemann is a well-established, classic text, providing an in-depth and comprehensive introduction to the field of high-energy particle acceleration and beam dynamics. The present 4th edition has been significantly revised, updated and expanded. The newly conceived Part I is an elementary introduction to the subject matter for undergraduate students. Part II gathers the basic tools in preparation of a more advanced treatment, summarizing the essentials of electrostatics and electrodynamics as well as of particle dynamics in electromagnetic fields. Part III is an extensive primer in beam dynamics, followed, in Part IV, by an introduction and description of the main beam parameters and including a new chapter on beam emittance and lattice design. Part V is devoted to the treatment of perturbations in beam dynamics. Part VI then discusses the details of charged particle acceleration. Parts VII and VIII introduce the more advanced topics of coupled beam dynamics and describe very intense bea...

  2. Accelerator research studies

    International Nuclear Information System (INIS)

    1992-01-01

    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 first year of a three-year funding cycle. The program consists of the following three tasks: TASK A, Study of Transport and Longitudinal Compression of Intense, High-Brightness Beams, TASK B, Study of Collective Ion Acceleration by Intense Electron Beams and Pseudospark Produced High Brightness Electron Beams; TASK C, Study of a Gyroklystron High-power Microwave Source for Linear Colliders. In this report we document the progress that has been made during the past year for each of the three tasks

  3. Accelerators for cancer therapy

    International Nuclear Information System (INIS)

    Lennox, Arlene J.

    2000-01-01

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

  4. Ion accelerators for space

    International Nuclear Information System (INIS)

    Slobodrian, R.J.; Potvin, L.

    1991-01-01

    The main purpose of the accelerators is to allow ion implantation in space stations and their neighborhoods. There are several applications of interest immediately useful in such environment: as ion engines and thrusters, as implanters for material science and for hardening of surfaces (relevant to improve resistance to micrometeorite bombardment of exposed external components), production of man made alloys, etc. The microgravity environment of space stations allows the production of substances (crystalline and amorphous) under conditions unknown on earth, leading to special materials. Ion implantation in situ of those materials would thus lead uninterruptedly to new substances. Accelerators for space require special design. On the one hand it is possible to forego vacuum systems simplifying the design and operation but, on the other hand, it is necessary to pay special attention to heat dissipation. Hence it is necessary to construct a simulator in vacuum to properly test prototypes under conditions prevailing in space

  5. Acceleration of microparticle

    CERN Document Server

    Shibata, H

    2002-01-01

    A microparticle (dust) ion source has been installed at the high voltage terminal of the 3.75 MV single ended Van de Graaff electrostatic accelerator and a beam line for microparticle experiments has been build at High Fluence Irradiation Facility (HIT) of Research Center for Nuclear Science and Technology, the University of Tokyo. Microparticle acceleration has been successful in obtaining expected velocities of 1-20 km/s or more for micron or submicron sized particles. Development of in situ dust detectors and analyzers on board satellites and spacecraft in the expected mass and velocity range of micrometeoroids and investigation of hypervelocity impact phenomena by using time of flight mass spectrometry, impact flash or luminescence measurement and scanning electron or laser microscope observation for metals, ceramics, polymers and semiconductors bombarded by micron-sized particles were started three years ago. (author)

  6. Hadron beams and accelerators

    International Nuclear Information System (INIS)

    Roser, T.

    1994-01-01

    There were four sessions on Hadron Beams and Accelerators with 7 talks on Siberian Snakes and spin rotators, 3 talks on polarization build-up of unpolarized beams in storage rings and 5. 9, and 3 talks on low, medium, and high energy polarimeters, respectively. In this paper I will briefly describe a few highlights from these sessions, giving emphasis to topics which I think will play an important role in the future

  7. ATLAS accelerator laboratory report

    International Nuclear Information System (INIS)

    Den Hartog, P.

    1986-01-01

    The operation of the ATLAS Accelerator is reported. Modifications are reported, including the installation of conductive tires for the Pelletron chain pulleys, installation of a new high frequency sweeper system at the entrance to the linac, and improvements to the rf drive ports of eight resonators to correct failures in the thermally conductive ceramic insulators. Progress is reported on the positive-ion injector upgrade for ATLAS. Also reported are building modifications and possible new uses for the tandem injector

  8. Accelerator simulation using computers

    International Nuclear Information System (INIS)

    Lee, M.; Zambre, Y.; Corbett, W.

    1992-01-01

    Every accelerator or storage ring system consists of a charged particle beam propagating through a beam line. Although a number of computer programs exits that simulate the propagation of a beam in a given beam line, only a few provide the capabilities for designing, commissioning and operating the beam line. This paper shows how a ''multi-track'' simulation and analysis code can be used for these applications

  9. Modulational effects in accelerators

    International Nuclear Information System (INIS)

    Satogata, T.

    1997-01-01

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

  10. Neutrino physics and accelerators

    International Nuclear Information System (INIS)

    Kaftanov, V.

    1978-01-01

    The history is described of experiments aimed at the study of direct neutrino-matter interactions conducted in the past twenty years. Experiments are outlined carried out with the objective of proving the existence of the intermediate W meson which had been predicted by the weak interaction theory. The methods of obtaining neutrino beams using accelerators and the detectors used are briefly shown. Also described are experiments to be conducted in the near future in different laboratories. (Z.J.)

  11. Hadron beams and accelerators

    International Nuclear Information System (INIS)

    Roser, T.

    1995-01-01

    There were four sessions on Hadron Beams and Accelerators with 7 talks on Siberian Snakes and spin rotators, 3 talks on polarization build-up of unpolarized beams in storage rings and 5, 9, and 3 talks on low, medium, and high energy polarimeters, respectively. In this paper I will briefly describe a few highlights from these sessions, giving emphasis to topics which I think will play an important role in the future. copyright 1995 American Institute of Physics

  12. Future Accelerator Magnet Needs

    International Nuclear Information System (INIS)

    Devred, Arnaud; Gourlay, Stephen A.; Yamamoto, Akira

    2005-01-01

    Superconducting magnet technology is continually evolving in order to meet the demanding needs of new accelerators and to provide necessary upgrades for existing machines. A variety of designs are now under development, including high fields and gradients, rapid cycling and novel coil configurations. This paper presents a summary of R and D programs in the EU, Japan and the USA. A performance comparison between NbTi and Nb 3 Sn along with fabrication and cost issues are also discussed

  13. LEP copper accelerating cavities

    CERN Multimedia

    Laurent Guiraud

    1999-01-01

    These copper cavities were used to generate the radio frequency electric field that was used to accelerate electrons and positrons around the 27-km Large Electron-Positron (LEP) collider at CERN, which ran from 1989 to 2000. The copper cavities were gradually replaced from 1996 with new superconducting cavities allowing the collision energy to rise from 90 GeV to 200 GeV by mid-1999.

  14. Introduction to Accelerators Physics

    International Nuclear Information System (INIS)

    Variola, A.

    2007-01-01

    This short course aims at giving to high energy physics students a preliminary introduction to accelerators basics. The arguments and the style were selected in this perspective. Consequently, topics such as the definition of beam parameters and luminosity were preferred to much more technical aspects. The calculation details were neglected to allow more important highlights on concepts and definitions. Some examples and exercises were suggested to summarize the different topics of the lessons

  15. Operation of the accelerator

    International Nuclear Information System (INIS)

    GANIL Team

    1992-01-01

    The operation of the GANIL accelerator during 1991 and the first half of 1992 is reported. Results obtained with new beams, metallic beams and the first tests with the new injector system using an ECR source installed on a 100 kV platform are also given. Statistics of operation and beam characteristics are presented. The computer control system is also discussed. (K.A.) 7 refs.; 3 figs.; 8 tabs

  16. Accelerating News Issue 3

    CERN Document Server

    Kahle, K; Tanguy, C; Wildner, E

    2012-01-01

    This summer saw CERN announce to a worldwide audience the discovery of a Higgs-like boson, so this issue takes a look at the machine behind the discovery, the LHC, as well as future plans for a possible Higgs factory in the form of LEP3. Looking ahead too are European strategies for particle physics and accelerator-based neutrino physics. In addition, taking stock of the work so far, HiLumi LHC and EuCARD showcase their latest results.

  17. Particle acceleration by pulsars

    International Nuclear Information System (INIS)

    Arons, Jonathan.

    1980-06-01

    The evidence that pulsars accelerate relativistic particles is reviewed, with emphasis on the γ-ray observations. The current state of knowledge of acceleration in strong waves is summarized, with emphasis on the inability of consistent theories to accelerate very high energy particles without converting too much energy into high energy photons. The state of viable models for pair creation by pulsars is summarized, with the conclusion that pulsars very likely lose rotational energy in winds instead of in superluminous strong waves. The relation of the pair creation models to γ-ray observations and to soft X-ray observations of pulsars is outlined, with the conclusion that energetically viable models may exist, but none have yet yielded useful agreement with the extant data. Some paths for overcoming present problems are discussed. The relation of the favored models to cosmic rays is discussed. It is pointed out that the pairs made by the models may have observable consequences for observation of positrons in the local cosmic ray flux and for observations of the 511 keV line from the interstellar medium. Another new point is that asymmetry of plasma supply from at least one of the models may qualitatively explain the gross asymmetry of the X-ray emission from the Crab nebula. It is also argued that acceleration of cosmic ray nuclei by pulsars, while energetically possible, can occur only at the boundary of the bubbles blown by the pulsars, if the cosmic ray composition is to be anything like that of the known source spectrum

  18. Basic accelerator optics

    CERN Document Server

    CERN. Geneva. Audiovisual Unit

    1985-01-01

    A complete derivation, from first principles, of the concepts and methods applied in linear accelerator and beamline optics will be presented. Particle motion and beam motion in systems composed of linear magnets, as well as weak and strong focusing and special insertions are treated in mathematically simple terms, and design examples for magnets and systems are given. This series of five lectures is intended to provide all the basic tools required for the design and operation of beam optical systems.

  19. Superconducting magnets for accelerators

    International Nuclear Information System (INIS)

    Denisov, Yu.N.

    1979-01-01

    Expediency of usage and possibilities arising in application of superconducting devices in magnetic systems of accelerators and experimental nuclear-physical devices are studied. Parameters of specific devices are given. It is emphasized that at the existing level of technological possibilities, construction and usage of superconducting magnetic systems in experimental nuclear physics should be thought of as possible, from the engineering, and expedient, from the economical viewpoints [ru

  20. Linear induction accelerator

    Science.gov (United States)

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

    1988-06-21

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

  1. Laser-driven electron accelerators

    International Nuclear Information System (INIS)

    Palmer, R.B.

    1981-01-01

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

  2. Optimizing accelerator technology

    CERN Multimedia

    Katarina Anthony

    2012-01-01

    A new EU-funded research and training network, oPAC, is bringing together 22 universities, research centres and industry partners to optimize particle accelerator technology. CERN is one of the network’s main partners and will host 5 early-stage researchers in the BE department.   A diamond detector that will be used for novel beam diagnostics applications in the oPAC project based at CIVIDEC. (Image courtesy of CIVIDEC.) As one of the largest Marie Curie Initial Training Networks ever funded by the EU – to the tune of €6 million – oPAC extends well beyond the particle physics community. “Accelerator physics has become integral to research in almost every scientific discipline – be it biology and life science, medicine, geology and material science, or fundamental physics,” explains Carsten P. Welsch, oPAC co-ordinator based at the University of Liverpool. “By optimizing the operation of accelerators, all of these...

  3. Equipartitioning in linear accelerators

    International Nuclear Information System (INIS)

    Jameson, R.A.

    1982-01-01

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

  4. Equipartitioning in linear accelerators

    International Nuclear Information System (INIS)

    Jameson, R.A.

    1981-01-01

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

  5. Laser driven particle acceleration

    International Nuclear Information System (INIS)

    Faure, J.

    2009-06-01

    This dissertation summarizes the last ten years of research at the Laboratory of Applied Optics on laser-plasma based electron acceleration. The main result consists of the development and study of a relativistic electron source with unique properties: high energy (100-300 MeV) in short distances (few millimeters), mono-energetic, ultra-short (few fs), stable and tunable. The manuscript describes the steps that led to understanding the physics, and then mastering it in order to produce this new electron source. Non linear propagation of the laser pulse in the plasma is first presented, with phenomena such as non linear wakefield excitation, relativistic and ponderomotive self-focusing in the short pulse regime, self-compression. Acceleration and injection of electrons are then reviewed from a theoretical perspective. Experimental demonstrations of self-injection in the bubble regime and then colliding pulse injection are then presented. These experiments were among the first to produce monoenergetic, high quality, stable and tunable electron beams from a laser-plasma accelerator. The last two chapters are dedicated to the characterization of the electron beam using transition radiation and to its applications to gamma radiography and radiotherapy. Finally, the perspectives of this research are presented in the conclusion. Scaling laws are used to determine the parameters that the electron beams will reach using peta-watt laser systems currently under construction. (author)

  6. SSC accelerator physics

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    Accelerator physicists at LBL began intensive work on the SSC in 1983, in support of the proposed 6.5-T magnet design, which, in turn, became reference design A during the Reference Designs Study. In that same study, LBL physicists formed the core of the accelerator physics group led by Fermilab's Don Edwards. In a period of only a few months, that group established preliminary parameters for a near-optimal design, produced conceptual designs based on three magnet types, addressed all significant beam lifetime and stability issues, and identified areas requiring further R and D. Since the conclusion of the Reference Designs Study, work has focused on the key SSC design issue, namely, single-particle stability in an imperfect magnetic field. At the end of fiscal 1984, much of the LBL accelerator physics group took its place in the SSC Central Design Group, whose headquarters at LBL will be the focus of nationwide SSC R and D efforts over the next several years

  7. The tandem betatron accelerator

    International Nuclear Information System (INIS)

    Keinigs, R.

    1991-01-01

    This paper reports that the tandem betatron is a compact, high-current induction accelerator that has the capability to accelerate electrons to an energy of order one gigavolt. Based upon the operating principle of a conventional betatron, the tandem betatron employs two synchronized induction cores operating 180 degrees out of phase. Embedded within the cores are the vacuum chambers, and these are connected by linear transport sections to allow for moving the beam back and forth between the two betatrons. The 180 degree phase shift between the core fluxes permits the circumvention of the flux swing constraint that limits the maximum energy gain of a conventional betatron. By transporting the beam between the synchronized cores, an electron can access more than one acceleration cycle, and thereby continue to gain energy. This added degree of freedom also permits a significant decrease in the size of the magnet system. Biasing coils provide independent control of the confining magnetic field. Provided that efficient beam switching can be performed, it appears feasible that a one gigavolt electron beam can be generated and confined. At this energy, a high current electron beam circulating in a one meter radius orbit could provide a very intense source of short wavelength (λ < 10 nm) synchrotron radiation. This has direct application to the emerging field of x-ray lithography. At more modest energies (10 MeV-30 MEV) a compact tandem betatron could be employed in the fields of medical radiation therapy, industrial radiography, and materials processing

  8. Turbulence and particle acceleration

    International Nuclear Information System (INIS)

    Scott, J.S.

    1975-01-01

    A model for the production of high energy particles in the supernova remnant Cas A is considered. The ordered expansion of the fast moving knots produce turbulent cells in the ambient interstellar medium. The turbulent cells act as magnetic scattering centers and charged particles are accelerated to large energies by the second order Fermi mechanism. Model predictions are shown to be consistent with the observed shape and time dependence of the radio spectrum, and with the scale size of magnetic field irregularities. Assuming a galactic supernova rate at 1/50 yr -1 , this mechanism is capable of producing the observed galactic cosmic ray flux and spectrum below 10 16 eV/nucleon. Several observed features of galactic cosmic rays are shown to be consistent with model predictions. A model for the objects known as radio tall galaxies is also presented. Independent blobs of magnetized plasma emerging from an active radio galaxy into an intracluster medium become turbulent due to Rayleigh--Taylor and Kelvin--Helmholz instabilities. The turbulence produces both in situ betatron and 2nd order Fermi accelerations. Predictions of the dependence of spectral index and flux on distance along the tail match observations well. Fitting provides values of physical parameters in the blobs. The relevance of this method of particle acceleration for the problem of the origin of x-ray emission in clusters of galaxies is discussed

  9. Accelerator mass spectrometry.

    Science.gov (United States)

    Hellborg, Ragnar; Skog, Göran

    2008-01-01

    In this overview the technique of accelerator mass spectrometry (AMS) and its use are described. AMS is a highly sensitive method of counting atoms. It is used to detect very low concentrations of natural isotopic abundances (typically in the range between 10(-12) and 10(-16)) of both radionuclides and stable nuclides. The main advantages of AMS compared to conventional radiometric methods are the use of smaller samples (mg and even sub-mg size) and shorter measuring times (less than 1 hr). The equipment used for AMS is almost exclusively based on the electrostatic tandem accelerator, although some of the newest systems are based on a slightly different principle. Dedicated accelerators as well as older "nuclear physics machines" can be found in the 80 or so AMS laboratories in existence today. The most widely used isotope studied with AMS is 14C. Besides radiocarbon dating this isotope is used in climate studies, biomedicine applications and many other fields. More than 100,000 14C samples are measured per year. Other isotopes studied include 10Be, 26Al, 36Cl, 41Ca, 59Ni, 129I, U, and Pu. Although these measurements are important, the number of samples of these other isotopes measured each year is estimated to be less than 10% of the number of 14C samples. Copyright 2008 Wiley Periodicals, Inc.

  10. Particle Accelerator Focus Automation

    Science.gov (United States)

    Lopes, José; Rocha, Jorge; Redondo, Luís; Cruz, João

    2017-08-01

    The Laboratório de Aceleradores e Tecnologias de Radiação (LATR) at the Campus Tecnológico e Nuclear, of Instituto Superior Técnico (IST) has a horizontal electrostatic particle accelerator based on the Van de Graaff machine which is used for research in the area of material characterization. This machine produces alfa (He+) and proton (H+) beams of some μA currents up to 2 MeV/q energies. Beam focusing is obtained using a cylindrical lens of the Einzel type, assembled near the high voltage terminal. This paper describes the developed system that automatically focuses the ion beam, using a personal computer running the LabVIEW software, a multifunction input/output board and signal conditioning circuits. The focusing procedure consists of a scanning method to find the lens bias voltage which maximizes the beam current measured on a beam stopper target, which is used as feedback for the scanning cycle. This system, as part of a wider start up and shut down automation system built for this particle accelerator, brings great advantages to the operation of the accelerator by turning it faster and easier to operate, requiring less human presence, and adding the possibility of total remote control in safe conditions.

  11. Electrostatic Plasma Accelerator (EPA)

    Science.gov (United States)

    Brophy, John R.; Aston, Graeme

    1995-01-01

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

  12. Particle Accelerator Focus Automation

    Directory of Open Access Journals (Sweden)

    Lopes José

    2017-08-01

    Full Text Available The Laboratório de Aceleradores e Tecnologias de Radiação (LATR at the Campus Tecnológico e Nuclear, of Instituto Superior Técnico (IST has a horizontal electrostatic particle accelerator based on the Van de Graaff machine which is used for research in the area of material characterization. This machine produces alfa (He+ and proton (H+ beams of some μA currents up to 2 MeV/q energies. Beam focusing is obtained using a cylindrical lens of the Einzel type, assembled near the high voltage terminal. This paper describes the developed system that automatically focuses the ion beam, using a personal computer running the LabVIEW software, a multifunction input/output board and signal conditioning circuits. The focusing procedure consists of a scanning method to find the lens bias voltage which maximizes the beam current measured on a beam stopper target, which is used as feedback for the scanning cycle. This system, as part of a wider start up and shut down automation system built for this particle accelerator, brings great advantages to the operation of the accelerator by turning it faster and easier to operate, requiring less human presence, and adding the possibility of total remote control in safe conditions.

  13. Accelerated Profile HMM Searches.

    Directory of Open Access Journals (Sweden)

    Sean R Eddy

    2011-10-01

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

  14. Collective focusing ion accelerator

    International Nuclear Information System (INIS)

    Goldin, F.J.

    1986-01-01

    The principal subject of this dissertation is the trapping confinement of pure electron plasmas in bumpy toroidal magnetic fields, with particular attention given to the trapping procedure and the behavior of the plasma during the final equilibrium. The most important aspects of the equilibrium studied were the qualitative nature of the plasma configuration and motion and its density, distribution and stability. The motivation for this study was that an unneutralized cloud of electrons contained in a toroidal system, sufficiently dense and stable, may serve to electrostatically focus ions (against centrifugal and self space charge forces) in a cyclic ion accelerator. Such an accelerator, known as a Collective Focusing Ion Accelerator (CFIA) could be far smaller than conventional designs (which use external magnetic fields directly to focus the ions) due to the smaller gyro-radium of an electron in a magnetic field of given strength. The electron cloud generally drifted poloidally at a finite radius from the toroidal minor axis. As this would preclude focusing ions with such clouds, damping this motion was investigated. Finite resistance in the normally perfectly conductive vessel wall did this. In further preparation for a working CFIA, additional experiments studied the effect of ions on the stability of the electron cloud

  15. Berkeley Proton Linear Accelerator

    Science.gov (United States)

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

    1953-10-13

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

  16. Heavy ion accelerating structure

    International Nuclear Information System (INIS)

    Pottier, Jacques.

    1977-01-01

    The heavy ion accelerating structure concerned in this invention is of the kind that have a resonance cavity inside which are located at least two longitudinal conducting supports electrically connected to the cavity by one of their ends in such a way that they are in quarter-wavelength resonance and in phase opposition. Slide tubes are electrically connected alternatively to one or the other of the two supports, they being electrically connected respectively to one or the other end of the side wall of the cavity. The feature of the structure is that it includes two pairs of supports symmetrically placed with respect to the centre line of the cavity, the supports of one pair fitted overhanging being placed symmetrically with respect to the centre line of the cavity, each slide tube being connected to the two supports of one pair. These support are connected to the slide wall of the cavity by an insulator located at their electrically free end. The accelerator structure composed of several structures placed end to end, the last one of which is fed by a high frequency field of adjustable amplitude and phase, enables a heavy ion linear accelerator to be built [fr

  17. Electron accelerators for environmental protection

    International Nuclear Information System (INIS)

    Zimek, Z.

    1998-01-01

    The primary objective of this publication is to provide information suitable for electron accelerators implementation in facilities applying radiation technology for environmental protection. It should be noticed that radiation processing has been successfully used in the fields of crosslinking polymer curing and medical products sterilization for more than 40 years. Practical application of radiation technology today extends on SO 2 and NO x removal from the flue gas (one of major power intensive radiation processing), destruction and removal of organic chemicals from water, decreasing bacteria content in the irradiated sludge and waste water. On the other hand the increased awareness of environmental pollution hazards and more stringent waste regulations in many countries may open stronger support for environmentally oriented technologies. This publication provides an evaluation of electron accelerators capabilities in respect of environmental applications where technological and economical criteria are now well defined. In order to determine the potential of electron accelerators, the literature data were examined as well visits and meetings with various accelerator manufacturers were performed by the author. Experience of the author in accelerator facilities construction and exploitation including those which were used for environmental protection are significant part of this publication. The principle of accelerator action was described in Chapter 1. Early development, accelerator classification and fields of accelerators application were included to this chapter as well. Details of accelerator construction was described in Chapter 2 to illustrate physical capability of accelerators to perform the function of ionizing radiation source. Electron beam extraction devices, under beam equipment, electron beam parameters and measuring methods were characterized in this chapter as well. Present studies of accelerator technology was described in Chapter 3, where

  18. Overview of accelerators in medicine

    International Nuclear Information System (INIS)

    Lennox, A.J.

    1993-06-01

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

  19. Introduction to Microwave Linear [Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Whittum, David H

    1999-01-04

    The elements of microwave linear accelerators are introduced starting with the principles of acceleration and accelerating structures. Considerations for microwave structure modeling and design are developed from an elementary point of view. Basic elements of microwave electronics are described for application to the accelerator circuit and instrumentation. Concepts of beam physics are explored together with examples of common beamline instruments. Charged particle optics and lattice diagnostics are introduced. Considerations for fixed-target and colliding-beam experimentation are summarized.

  20. Stochastic acceleration by hydromagnetic turbulence

    International Nuclear Information System (INIS)

    Kulsrud, R.M.

    1979-03-01

    A general theory for particle acceleration by weak hydromagnetic turbulence with a given spectrum of waves is described. Various limiting cases, corresponding to Fermi acceleration and magnetic pumping, are discussed and two numerical examples illustrating them are given. An attempt is made to show that the expression for the rate of Fermi acceleration is valid for finite amplitudes

  1. Damage limits of accelerator equipment

    CERN Document Server

    Rosell, Gemma

    2014-01-01

    Beam losses occur in particle accelerators for various reasons. The effect of lost particles on accelerator equipment becomes more severe with the increasing energies and intensities. The present study is focused on the damage potential of the proton beam as a function of particle energy and beam size. Injection and extraction energies of different accelerators at CERN were considered.

  2. ACCELERATORS: Nonlinear dynamics in Sardinia

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    In the last few years, two schools devoted to accelerator physics have been set up, one on either side of the Atlantic. The US School on High Energy Particle Accelerators has organized Summer Schools on the physics of particle accelerators, hosted by the major American Laboratories, each year since 1981

  3. New techniques for particle accelerators

    International Nuclear Information System (INIS)

    Sessler, A.M.

    1990-06-01

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

  4. ACCELERATORS: Nonlinear dynamics in Sardinia

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1985-05-15

    In the last few years, two schools devoted to accelerator physics have been set up, one on either side of the Atlantic. The US School on High Energy Particle Accelerators has organized Summer Schools on the physics of particle accelerators, hosted by the major American Laboratories, each year since 1981.

  5. High intensity circular proton accelerators

    International Nuclear Information System (INIS)

    Craddock, M.K.

    1987-12-01

    Circular machines suitable for the acceleration of high intensity proton beams include cyclotrons, FFAG accelerators, and strong-focusing synchrotrons. This paper discusses considerations affecting the design of such machines for high intensity, especially space charge effects and the role of beam brightness in multistage accelerators. Current plans for building a new generation of high intensity 'kaon factories' are reviewed. 47 refs

  6. Modern accelerators in ancient Rome

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    For the first time, the achievements and hopes of the broad European accelerator community were brought together in a European Particle Accelerator Conference, held in Rome in June. Ranging from the vast machines at CERN to the small medical accelerators operating in thousands of hospitals, the programme underlined how modern civilization has benefited from the ability to handle charged particle beams

  7. Modern accelerators in ancient Rome

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1988-09-15

    For the first time, the achievements and hopes of the broad European accelerator community were brought together in a European Particle Accelerator Conference, held in Rome in June. Ranging from the vast machines at CERN to the small medical accelerators operating in thousands of hospitals, the programme underlined how modern civilization has benefited from the ability to handle charged particle beams.

  8. Theoretical problems in accelerator physics

    International Nuclear Information System (INIS)

    1992-01-01

    This report discusses the following research on accelerators: computational methods; higher order mode suppression in accelerators structures; overmoded waveguide components and application to SLED II and power transport; rf sources; accelerator cavity design for a B factory asymmetric collider; and photonic band gap cavities

  9. Industrial use of electron accelerators

    International Nuclear Information System (INIS)

    Tabata, Y.

    1980-01-01

    Use of accelerators in various fields of Japan is reviewed. The total number of accelerators in Japan and its relation with others fields, the number of accelerators for use in radiation processing, comparison between the use of low and high energy machines, etc... is done. (E.G.) [pt

  10. Simulation Study Using an Injection Phase-locked Magnetron as an Alternative Source for SRF Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Haipeng [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Plawski, Tomasz E. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Rimmer, Robert A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    2015-09-01

    As a drop-in replacement for the CEBAF CW klystron system, a 1497 MHz, CW-type high-efficiency magnetron using injection phase lock and amplitude variation is attractive. Amplitude control using magnetic field trimming and anode voltage modulation has been studied using analytical models and MATLAB/Simulink simulations. Since the 1497 MHz magnetron has not been built yet, previously measured characteristics of a 2.45GHz cooker magnetron are used as reference. The results of linear responses to the amplitude and phase control of a superconducting RF (SRF) cavity, and the expected overall benefit for the current CEBAF and future MEIC RF systems are presented in this paper.

  11. Particle acceleration by collective effects

    International Nuclear Information System (INIS)

    Keefe, D.

    1976-01-01

    Successful acceleration of protons and other ions has been achieved experimentally in this decade by a number of different collective methods. The attainment of very high accelerating fields has been established although so far the acceleration distance has been confined to only a few centimeters. Efforts are in progress to understand the accelerating mechanisms in detail and, as a result, to devise ways of extending considerably the acceleration distance. This paper is intended to review the current progress, expectations, and limitations of the different approaches. (author)

  12. Particle acceleration by collective effects

    International Nuclear Information System (INIS)

    Keefe, D.

    1976-09-01

    Successful acceleration of protons and other ions has been achieved experimentally in this decade by a number of different collective methods. The attainment of very high accelerating fields has been established although so far the acceleration distance has been confined to only a few centimeters. Efforts are in progress to understand the accelerating mechanisms in detail and, as a result, to devise ways of extending considerably the acceleration distance. A review is given of the current progress, expectations, and limitations of the different approaches

  13. High intensity proton accelerator program

    International Nuclear Information System (INIS)

    Kaneko, Yoshihiko; Mizumoto, Motoharu; Nishida, Takahiko

    1991-06-01

    Industrial applications of proton accelerators to the incineration of the long-lived nuclides contained in the spent fuels have long been investigated. Department of Reactor Engineering of Japan Atomic Energy Research Institute (JAERI) has formulated the Accelerator Program through the investigations on the required performances of the accelerator and its development strategies and also the research plan using the accelerator. Outline of the Program is described in the present report. The target of the Program is the construction of the Engineering Test Accelerators (ETA) of the type of a linear accelerator with the energy 1.5 GeV and the proton current ∼10 mA. It is decided that the construction of the Basic Technology Accelerator (BTA) is necessary as an intermediate step, aiming at obtaining the required technical basis and human resources. The Basic Technology Accelerator with the energy of 10 MeV and with the current of ∼10 mA is composed of the ion source, RFQ and DTL, of which system forms the mock-up of the injector of ETA. Development of the high-β structure which constitutes the main acceleration part of ETA is also scheduled. This report covers the basic parameters of the Basic Technology Accelerator (BTA), development steps of the element and system technologies of the high current accelerators and rough sketch of ETA which can be prospected at present. (J.P.N.)

  14. Plasma-focused cyclic accelerators

    International Nuclear Information System (INIS)

    Mondelli, A.A.; Chernin, D.P.

    1985-01-01

    The use of ambient plasma to neutralize the transverse forces of an intense particle beam has been known for many years. Most recently, the so-called ion-focused regime (IFR) for beam propagation has been used as a means of focusing intense electron beams in linear accelerators and suggested for injecting an electron beam across magnetic field lines into a high-current cyclic accelerator. One technique for generating the required background plasma for IFR propagation is to use a laser to ionize ambient gas in the accelerator chamber. This paper discusses an alternative means of plasma production for IFR, viz. by using RF breakdown. For this approach the accelerator chamber acts as a waveguide. This technique is not limited to toroidal accelerators. It may be applied to any accelerator or recirculator geometry as well as for beam steering and for injection or extraction of beams in closed accelerator configurations

  15. APT accelerator. Topical report

    International Nuclear Information System (INIS)

    Lawrence, G.; Rusthoi, D.

    1995-03-01

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

  16. VLHC accelerator physics

    Energy Technology Data Exchange (ETDEWEB)

    Michael Blaskiewicz et al.

    2001-11-01

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

  17. APT accelerator. Topical report

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-03-01

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

  18. Medical applications of accelerators

    CERN Document Server

    Rossi, Sandro

    1998-01-01

    At Present, about five thousands accelerators are devoted to biomedical applications. They are mainly used in radiotherapy, research and medical radioisotopes production. In this framework oncological hadron-therapy deserves particular attention since it represents a field in rapid evolution thanks to the joint efforts of laboratories with long experiences in particle physics. It is the case of CERN where the design of an optimised synchrotron for medical applications has been pursued. These lectures present these activities with particular attention to the new developments which are scientifically interesting and/or economically promising.

  19. ACCELERATING NANO-TECHNOLOGICAL

    DEFF Research Database (Denmark)

    Jensen, Jens Stissing; Koch, Christian

    2007-01-01

    By viewing the construction industry as a technological innovation system (TIS) this paper discusses possible initiatives to accelerate nanotechnological innovations. The point of departure is a recent report on the application of nano-technology in the Danish construction industry, which concludes...... of the system are furthermore poorly equipped at identifying potentials within high-tech areas. In order to exploit the potentials of nano-technology it is thus argued that an alternative TIS needs to be established. Initiatives should identify and support “incubation rooms” or marked niches in order...

  20. Accelerated Innovation Pilot

    Science.gov (United States)

    Davis, Jeffrey

    2012-01-01

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