WorldWideScience

Sample records for acceleration

  1. Accelerator

    International Nuclear Information System (INIS)

    The invention claims equipment for stabilizing the position of the front covers of the accelerator chamber in cyclic accelerators which significantly increases accelerator reliability. For stabilizing, it uses hydraulic cushions placed between the electromagnet pole pieces and the front chamber covers. The top and the bottom cushions are hydraulically connected. The cushions are disconnected and removed from the hydraulic line using valves. (J.P.)

  2. Linear Accelerators

    CERN Document Server

    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.

  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. Accelerating Value Creation with Accelerators

    DEFF Research Database (Denmark)

    Jonsson, Eythor Ivar

    2015-01-01

    accelerator programs. Microsoft runs accelerators in seven different countries. Accelerators have grown out of the infancy stage and are now an accepted approach to develop new ventures based on cutting-edge technology like the internet of things, mobile technology, big data and virtual reality. It is also...... with the traditional audit and legal universes and industries are examples of emerging potentials both from a research and business point of view to exploit and explore further. The accelerator approach may therefore be an Idea Watch to consider, no matter which industry you are in, because in essence accelerators...

  5. Laser accelerator

    OpenAIRE

    Vigil, Ricardo

    2014-01-01

    Approved for public release; distribution is unlimited In 1979,W. B. Colson and S. K. Ride proposed a new kind of electron accelerator using a uniform magnetic field in combination with a circularly-polarized laser field. A key concept is to couple the oscillating electric field to the electron’s motion so that acceleration is sustained. This dissertation investigates the performance of the proposed laser accelerator using modern high powered lasers and mag-netic fields that are significan...

  6. 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.

  7. Accelerator operations

    International Nuclear Information System (INIS)

    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

  8. Advanced accelerators

    International Nuclear Information System (INIS)

    This report discusses the suitability of four novel particle acceleration technologies for multi-TeV particle physics machines: laser driven linear accelerators (linac), plasma beat-wave devices, plasma wakefield devices, and switched power and cavity wakefield linacs. The report begins with the derivation of beam parameters practical for multi-TeV devices. Electromagnetic field breakdown of materials is reviewed. The two-beam accelerator scheme for using a free electron laser as the driver is discussed. The options recommended and the conclusions reached reflect the importance of cost. We recommend that more effort be invested in achieving a self-consistent range of TeV accelerator design parameters. Beat-wave devices have promise for 1-100 GeV applications and, while not directly scalable to TeV designs, the current generation of ideas are encouraging for the TeV regime. In particular, surfatrons, finite-angle optical mixing devices, plasma grating accelerator, and the Raman forward cascade schemes all deserve more complete analysis. The exploitation of standard linac geometry operated in an unconventional mode is in a phase of rapid evolution. While conceptual projects abound, there are no complete designs. We recommend that a fraction of sponsored research be devoted to this approach. Wakefield devices offer a great deal of potential; trades among their benefits and constraints are derived and discussed herein. The study of field limitation processes has received inadequate attention; this limits experiment designers. The costs of future experiments are such that investment in understanding these processes is prudent. 34 refs., 12 figs., 3 tabs

  9. KEKB accelerator

    International Nuclear Information System (INIS)

    KEKB, the B-Factory at High Energy Accelerator Research Organization (KEK) recently achieved the luminosity of 1 x 1034 cm-2s-1. This luminosity is two orders higher than the world's level at 1990 when the design of KEKB started. This unprecedented result was made possible by KEKB's innovative design and technology in three aspects - beam focusing optics, high current storage, and beam - beam interaction. Now KEKB is leading the luminosity frontier of the colliders in the world. (author)

  10. Accelerating networks

    International Nuclear Information System (INIS)

    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

  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. accelerating cavity

    CERN Multimedia

    On the inside of the cavitytThere 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.

  13. Linear Accelerator (LINAC)

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Linear Accelerator A linear accelerator (LINAC) customizes high energy x-rays to ... ensured? What is this equipment used for? A linear accelerator (LINAC) is the device most commonly used ...

  14. 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/

  15. The direction of acceleration

    Science.gov (United States)

    Wilhelm, Thomas; Burde, Jan-Philipp; Lück, Stephan

    2015-11-01

    Acceleration is a physical quantity that is difficult to understand and hence its complexity is often erroneously simplified. Many students think of acceleration as equivalent to velocity, a ˜ v. For others, acceleration is a scalar quantity, which describes the change in speed Δ|v| or Δ|v|/Δt (as opposed to the change in velocity). The main difficulty with the concept of acceleration therefore lies in developing a correct understanding of its direction. The free iOS app AccelVisu supports students in acquiring a correct conception of acceleration by showing acceleration arrows directly at moving objects.

  16. San Francisco Accelerator Conference

    International Nuclear Information System (INIS)

    '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

  17. 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.

  18. Standing wave linear accelerator

    International Nuclear Information System (INIS)

    Consideration is being given to standing wave linear accelerator containing generator, phase shifter, two accelerating resonator sections, charged particle injector and waveguide bridge. Its first arm is oined up with generator via the phase shifter, the second and the third ones-with accelerating sections and the fourth one - with HF-power absorber. HF-power absorber represents a section of circular diaphragmatic wavequide with transformer with input wave and intrawaveguide output load located between injector and the first accelerating section. The section possesses holes in side walls lying on accelerator axis. The distances between centers of the last cell of the fast accelerating section and the first cell of the second accelerating sectiOn equal (2n+3)lambda/4, where n=1, 2, 3..., lambda - wave length of generator. The suggested system enables to improve by one order spectral characteristics of accelerators as compared to the prototype in which magnetrons are used as generator

  19. Accelerator Technology Division

    Science.gov (United States)

    1992-04-01

    In fiscal year (FY) 1991, the Accelerator Technology (AT) division continued fulfilling its mission to pursue accelerator science and technology and to develop new accelerator concepts for application to research, defense, energy, industry, and other areas of national interest. This report discusses the following programs: The Ground Test Accelerator Program; APLE Free-Electron Laser Program; Accelerator Transmutation of Waste; JAERI, OMEGA Project, and Intense Neutron Source for Materials Testing; Advanced Free-Electron Laser Initiative; Superconducting Super Collider; The High-Power Microwave Program; (Phi) Factory Collaboration; Neutral Particle Beam Power System Highlights; Accelerator Physics and Special Projects; Magnetic Optics and Beam Diagnostics; Accelerator Design and Engineering; Radio-Frequency Technology; Free-Electron Laser Technology; Accelerator Controls and Automation; Very High-Power Microwave Sources and Effects; and GTA Installation, Commissioning, and Operations.

  20. High Energy Particle Accelerators

    CERN Multimedia

    Audio Productions, Inc, New York

    1960-01-01

    Film about the different particle accelerators in the US. Nuclear research in the US has developed into a broad and well-balanced program.Tour of accelerator installations, accelerator development work now in progress and a number of typical experiments with high energy particles. Brookhaven, Cosmotron. Univ. Calif. Berkeley, Bevatron. Anti-proton experiment. Negative k meson experiment. Bubble chambers. A section on an electron accelerator. Projection of new accelerators. Princeton/Penn. build proton synchrotron. Argonne National Lab. Brookhaven, PS construction. Cambridge Electron Accelerator; Harvard/MIT. SLAC studying a linear accelerator. Other research at Madison, Wisconsin, Fixed Field Alternate Gradient Focusing. (FFAG) Oakridge, Tenn., cyclotron. Two-beam machine. Comments : Interesting overview of high energy particle accelerators installations in the US in these early years. .

  1. Maximal Acceleration Is Nonrotating

    OpenAIRE

    Page, Don N.

    1997-01-01

    In a stationary axisymmetric spacetime, the angular velocity of a stationary observer that Fermi-Walker transports its acceleration vector is also the angular velocity that locally extremizes the magnitude of the acceleration of such an observer, and conversely if the spacetime is also symmetric under reversing both t and phi together. Thus a congruence of Nonrotating Acceleration Worldlines (NAW) is equivalent to a Stationary Congruence Accelerating Locally Extremely (SCALE). These congruenc...

  2. A Solid state accelerator

    International Nuclear Information System (INIS)

    We present a solid state accelerator concept utilizing particle acceleration along crystal channels by longitudinal electron plasma waves in a metal. Acceleration gradients of order 100 GV/cm are theoretically possible, but channeling radiation limits the maximum attainable energy to 105 TeV for protons. Beam dechanneling due to multiple scattering is substantially reduced by the high acceleration gradient. Plasma wave dissipation and generation in metals are also discussed

  3. Applications of particle accelerators

    International Nuclear Information System (INIS)

    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.)

  4. Accelerators at school

    International Nuclear Information System (INIS)

    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

  5. Acceleration: It's Elementary

    Science.gov (United States)

    Willis, Mariam

    2012-01-01

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

  6. 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.

  7. Accelerators and Dinosaurs

    CERN Document Server

    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)

  8. Far field acceleration

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Direct Laser Acceleration in Laser Wakefield Accelerators

    OpenAIRE

    Shaw, Jessica

    2016-01-01

    In this dissertation, the direct laser acceleration (DLA) of ionization-injected electrons in a laser wakefield accelerator (LWFA) operating in the quasi-blowout regime has been investigated through experiment and simulation. In the blowout regime of LWFA, the radiation pressure of an intense laser pulse can push a majority of the plasma electrons out and around the main body of the pulse. The expelled plasma electrons feel the electrostatic field of the relatively-stationary ions and are t...

  10. 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.

  11. Induction linear accelerators

    Science.gov (United States)

    Birx, Daniel

    1992-03-01

    Among the family of particle accelerators, the Induction Linear Accelerator is the best suited for the acceleration of high current electron beams. Because the electromagnetic radiation used to accelerate the electron beam is not stored in the cavities but is supplied by transmission lines during the beam pulse it is possible to utilize very low Q (typicallymarriage of liner accelerator technology and nonlinear magnetic compressors has produced some unique capabilities. It now appears possible to produce electron beams with average currents measured in amperes, peak currents in kiloamperes and gradients exceeding 1 MeV/meter, with power efficiencies approaching 50%. The nonlinear magnetic compression technology has replaced the spark gap drivers used on earlier accelerators with state-of-the-art all-solid-state SCR commutated compression chains. The reliability of these machines is now approaching 1010 shot MTBF. In the following paper we will briefly review the historical development of induction linear accelerators and then discuss the design considerations.

  12. Particle-accelerator decommissioning

    International Nuclear Information System (INIS)

    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

  13. Particle-accelerator decommissioning

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. An introduction to acceleration mechanisms

    International Nuclear Information System (INIS)

    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

  15. 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.

  16. Switched Matrix Accelerator

    International Nuclear Information System (INIS)

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

  17. 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...

  18. Leaky Fermi accelerators

    CERN Document Server

    Shah, Kushal; Rom-Kedar, Vered; Turaev, Dmitry

    2015-01-01

    A Fermi accelerator is a billiard with oscillating walls. A leaky accelerator interacts with an environment of an ideal gas at equilibrium by exchange of particles through a small hole on its boundary. Such interaction may heat the gas: we estimate the net energy flow through the hole under the assumption that the particles inside the billiard do not collide with each other and remain in the accelerator for sufficiently long time. The heat production is found to depend strongly on the type of the Fermi accelerator. An ergodic accelerator, i.e. one which has a single ergodic component, produces a weaker energy flow than a multi-component accelerator. Specifically, in the ergodic case the energy gain is independent of the hole size, whereas in the multi-component case the energy flow may be significantly increased by shrinking the hole size.

  19. Nuclear physics accelerator facilities

    International Nuclear Information System (INIS)

    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

  20. Accelerator reliability workshop

    International Nuclear Information System (INIS)

    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

  1. High Gradient Accelerator Research

    Energy Technology Data Exchange (ETDEWEB)

    Temkin, Richard [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Dept. of Physics. Plasma Science and Fusion Center

    2016-07-12

    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.

  2. High Gradient Accelerator Research

    Energy Technology Data Exchange (ETDEWEB)

    Temkin, Richard [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Dept. of Physics. Plasma Science and Fusion Center

    2016-07-12

    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.

  3. Accelerator Modeling with MATLAB Accelerator Toolbox

    International Nuclear Information System (INIS)

    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

  4. Angular velocities, angular accelerations, and coriolis accelerations

    Science.gov (United States)

    Graybiel, A.

    1975-01-01

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

  5. Racetrack linear accelerators

    International Nuclear Information System (INIS)

    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)

  6. COLLECTIVE-FIELD ACCELERATION

    Energy Technology Data Exchange (ETDEWEB)

    Sessler, Andrew M.

    1969-07-04

    Diverse methods proposed for the acceleration of particles by means of collective fields are reviewed. A survey is made of the various currently active experimental programs devoted to investigating collective acceleration, and the present status of the research is briefly noted.

  7. KEK digital accelerator

    Science.gov (United States)

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

    2011-07-01

    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.

  8. 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)

  9. Accelerators for energy production

    International Nuclear Information System (INIS)

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

  10. 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?

  11. Maximal Acceleration Is Nonrotating

    CERN Document Server

    Page, D N

    1998-01-01

    In a stationary axisymmetric spacetime, the angular velocity of a stationary observer that Fermi-Walker transports its acceleration vector is also the angular velocity that locally extremizes the magnitude of the acceleration of such an observer, and conversely if the spacetime is also symmetric under reversing both t and phi together. Thus a congruence of Nonrotating Acceleration Worldlines (NAW) is equivalent to a Stationary Congruence Accelerating Locally Extremely (SCALE). These congruences are defined completely locally, unlike the case of Zero Angular Momentum Observers (ZAMOs), which requires knowledge around a symmetry axis. The SCALE subcase of a Stationary Congruence Accelerating Maximally (SCAM) is made up of stationary worldlines that may be considered to be locally most nearly at rest in a stationary axisymmetric gravitational field. Formulas for the angular velocity and other properties of the SCALEs are given explicitly on a generalization of an equatorial plane, infinitesimally near a symmetry...

  12. Linear induction accelerator

    International Nuclear Information System (INIS)

    This paper examines a new layout for the injector and accelerating sectins of a linear induction accelerator. The sections are combined in a single housing: an induction system with a current-pulse generator based on double strip shaping lines laid over ferromagnetic cores; a multichannel spark discharger with forced current division among channels; and a system for core demagnetization and electron-beam formation and transport. The results of formation of an electron beam in the injector system and its acceleration in the first accelerating section of the accelerator for injection of beams with energies of 0.2-0.4 MeV, currents of 1-2 kA, and pulse durations of 60 nsec are given

  13. Collinear wake field acceleration

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    Siemann, R.H.; /SLAC

    2011-10-24

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

  15. 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 ...

  16. 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.

  17. Accelerator programme at CAT

    International Nuclear Information System (INIS)

    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)

  18. Collective ion acceleration

    International Nuclear Information System (INIS)

    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

  19. Accelerator Toolbox for MATLAB

    International Nuclear Information System (INIS)

    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

  20. Hadron accelerators in medicine

    Energy Technology Data Exchange (ETDEWEB)

    Amaldi, U. [European Organization for Nuclear Research (CERN), Geneva (Switzerland). Accelerator School; Silari, M. [Consiglio Nazionale delle Ricerche, Milan (Italy)

    1996-12-31

    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) 28 refs.

  1. Confronting Twin Paradox Acceleration

    Science.gov (United States)

    Murphy, Thomas W.

    2016-05-01

    The resolution to the classic twin paradox in special relativity rests on the asymmetry of acceleration. Yet most students are not exposed to a satisfactory analysis of what exactly happens during the acceleration phase that results in the nonaccelerated observer's more rapid aging. The simple treatment presented here offers both graphical and quantitative solutions to the problem, leading to the correct result that the acceleration-induced age gap is 2Lβ years when the one-way distance L is expressed in light-years and velocity β ≡v/c .

  2. Entropic accelerating universe

    Energy Technology Data Exchange (ETDEWEB)

    Easson, Damien A., E-mail: easson@asu.ed [Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8568 (Japan); Department of Physics and School of Earth and Space Exploration and Beyond Center, Arizona State University, Phoenix, AZ 85287-1504 (United States); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106-4030 (United States); Frampton, Paul H., E-mail: frampton@physics.unc.ed [Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8568 (Japan); Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC 27599 (United States); Smoot, George F., E-mail: gfsmoot@lbl.go [Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8568 (Japan); Lawrence Berkeley National Lab, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Physics Department, University of California, Berkeley, CA 94720 (United States); Institute for the Early Universe, Ewha Womans University and Advanced Academy, Seoul (Korea, Republic of); Chaire Blaise Pascale, Universite Paris Denis Diderot, Paris (France)

    2011-01-31

    To accommodate the observed accelerated expansion of the universe, one popular idea is to invoke a driving term in the Friedmann-Lemaitre equation of dark energy which must then comprise 70% of the present cosmological energy density. We propose an alternative interpretation which takes into account the entropy and temperature intrinsic to the horizon of the universe due to the information holographically stored there. Dark energy is thereby obviated and the acceleration is due to an entropic force naturally arising from the information storage on the horizon surface screen. We consider an additional quantitative approach inspired by surface terms in general relativity and show that this leads to the entropic accelerating universe.

  3. ACCELERATORS: School prizes

    International Nuclear Information System (INIS)

    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

  4. Auroral electron acceleration

    International Nuclear Information System (INIS)

    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)

  5. The particle accelerator

    International Nuclear Information System (INIS)

    As the Palais de la Decouverte (in Paris) is the sole scientific vulgarization establishment in the world to operate an actual particle accelerator able to provoke different types of nuclear reactions, the author recalls some historical aspects of the concerned department since the creation of the 'Radioactivity - Atom synthesis' department in 1937. He recalls the experiments which were then performed, the installation of the particle accelerator in 1964 and its renewal. He describes what's going on in this accelerator. He gives an overview of the difficulties faced after it has been decided to move it, of the works which had to be performed, and of radiation protection measures

  6. SPS accelerating cavity

    CERN Multimedia

    1983-01-01

    See photo 8202397: View towards the downstream end of one of the SPS accelerating cavities (200 MHz, travelling wave structure). See 7603195 and 8011289 for more details, 7411032 for the travelling wave structure, and also 8104138.

  7. SPS accelerating cavity

    CERN Multimedia

    1983-01-01

    View towards the downstream end of one of the SPS accelerating cavities (200 MHz, travelling wave structure). See 7603195 and 8011289 for more details, 7411032 for the travelling wave structure, and also 8104138.

  8. 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.

  9. Dimension Driven Accelerating Universe

    CERN Document Server

    Chatterjee, S

    2009-01-01

    The current acceleration of the universe leads us to investigate higher dimensional gravity theory, which is able to explain acceleration from a theoretical view point without the need of introducing dark energy by hand. We argue that the terms containing higher dimensional metric coefficients produce an extra negative pressure that apparently drives an acceleration of the 3D space, tempting us to suggest that the accelerating universe seems to act as a window to the existence of extra spatial dimensions. Interesting to point out that in this case our cosmology apparently mimics the well known quintessence scenario fuelled by a generalised Chaplygin-type of fluid where a smooth transition from a dust dominated model to a de Sitter like one takes place. Correspondence to models generated by a tachyonic form of matter is also briefly discussed.

  10. Revisiting Caianiello's Maximal Acceleration

    OpenAIRE

    Papini, G.

    2003-01-01

    A quantum mechanical limit on the speed of orthogonality evolution justifies the last remaining assumption in Caianiello's derivation of the maximal acceleration. The limit is perfectly compatible with the behaviour of superconductors of the first type.

  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. A symmetrical rail accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Igenbergs, E. (Technische Univ. Muenchen, Lehrstuhl fuer Raumfahrttechnik, Richard-Wagner-Strasse 18, 8000 Muenchen 2 (DE))

    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.

  13. Advanced Accelerator Concepts

    International Nuclear Information System (INIS)

    This conference proceedings represent the results of theThird Advanced Accelerator Concepts Workshop held in PortJefferson, New York. The workshop was sponsored by the U.S.Department of Energy, the Office of Navel Research and BrookhavenNational Laboratory. The purpose was to assess new techniques forproduction of ultra-high gradient acceleration and to addressengineering issues in achieving this goal. There are eighty-onepapers collected in the proceedings and all have been abstractedfor the database

  14. CEBAF Accelerator Achievements

    International Nuclear Information System (INIS)

    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.

  15. Accelerating Cosmologies from Compactification

    CERN Document Server

    Townsend, P K; Townsend, Paul K.; Wohlfarth, Mattias N.R.

    2003-01-01

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

  16. Designing reliability into accelerators

    International Nuclear Information System (INIS)

    Future accelerators will have to provide a high degree of reliability. Quality must be designed in right from the beginning and must remain a central theme throughout the project. The problem is similar to the problems facing US industry today, and examples of the successful application of quality engineering will be given. Different aspects of an accelerator project will be addressed: Concept, Design, Motivation, Management Techniques, and Fault Diagnosis. The importance of creating and maintaining a coherent team will be stressed

  17. Accelerated cyclic corrosion tests

    OpenAIRE

    Prošek T.

    2016-01-01

    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 p...

  18. Accelerating News Issue 2

    CERN Document Server

    Kahle, K; Wildner, E

    2012-01-01

    In this summer issue we look at how developments in collimator materials could have applications in aerospace and beyond, and how Polish researchers are harnessing accelerators for medical and industrial uses. We see how the LHC luminosity upgrade is linking with European industry and US researchers, and how the neutrino oscillation community is progressing. We find out the mid-term status of TIARA-PP and how it is mapping European accelerator education resources.

  19. Nuclear physics accelerator facilities

    International Nuclear Information System (INIS)

    Brief descriptions are given of DOE and Nuclear Physics program operated and sponsored accelerator facilities. Specific facilities covered are the Argonne Tandem/Linac Accelerator System, the Tandem/AGS Heavy Ion Facility at Brookhaven National Laboratory, the proposed Continuous Beam Accelerator at Newport News, Virginia, the Triangle Universities Nuclear Laboratory at Duke University, the Bevalac and the SuperHILAC at Lawrence Berkeley Laboratory, the 88-Inch Cyclotron at Lawrence Berkeley Laboratory, the Clinton P. Anderson Meson Physics Facility at Los Alamos National Laboratory, the Bates Linear Accelerator Center at Massachusetts Institute of Technology, the Holifield Heavy Ion Research Facility at Oak Ridge National Laboratory, the Nuclear Physics Injector at Stanford Linear Accelerator Center, the Texas A and M Cyclotrons, the Tandem/Superconducting Booster Accelerator at the University of Washington and the Tandem Van de Graaff at the A.W. Wright Nuclear Structure Laboratory of Yale University. Included are acquisition cost, research programs, program accomplishments, future directions, and operating parameters of each facility

  20. Accelerators for America's Future

    Science.gov (United States)

    Bai, Mei

    2016-03-01

    Particle accelerator, a powerful tool to energize beams of charged particles to a desired speed and energy, has been the working horse for investigating the fundamental structure of matter and fundermental laws of nature. Most known examples are the 2-mile long Stanford Linear Accelerator at SLAC, the high energy proton and anti-proton collider Tevatron at FermiLab, and Large Hadron Collider that is currently under operation at CERN. During the less than a century development of accelerator science and technology that led to a dazzling list of discoveries, particle accelerators have also found various applications beyond particle and nuclear physics research, and become an indispensible part of the economy. Today, one can find a particle accelerator at almost every corner of our lives, ranging from the x-ray machine at the airport security to radiation diagnostic and therapy in hospitals. This presentation will give a brief introduction of the applications of this powerful tool in fundermental research as well as in industry. Challenges in accelerator science and technology will also be briefly presented

  1. Diffusive Shock Acceleration and Reconnection Acceleration Processes

    Science.gov (United States)

    Zank, G. P.; Hunana, P.; Mostafavi, P.; Le Roux, J. A.; Li, Gang; Webb, G. M.; Khabarova, O.; Cummings, A.; Stone, E.; Decker, R.

    2015-12-01

    Shock waves, as shown by simulations and observations, can generate high levels of downstream vortical turbulence, including magnetic islands. We consider a combination of diffusive shock acceleration (DSA) and downstream magnetic-island-reconnection-related processes as an energization mechanism for charged particles. Observations of electron and ion distributions downstream of interplanetary shocks and the heliospheric termination shock (HTS) are frequently inconsistent with the predictions of classical DSA. We utilize a recently developed transport theory for charged particles propagating diffusively in a turbulent region filled with contracting and reconnecting plasmoids and small-scale current sheets. Particle energization associated with the anti-reconnection electric field, a consequence of magnetic island merging, and magnetic island contraction, are considered. For the former only, we find that (i) the spectrum is a hard power law in particle speed, and (ii) the downstream solution is constant. For downstream plasmoid contraction only, (i) the accelerated spectrum is a hard power law in particle speed; (ii) the particle intensity for a given energy peaks downstream of the shock, and the distance to the peak location increases with increasing particle energy, and (iii) the particle intensity amplification for a particular particle energy, f(x,c/{c}0)/f(0,c/{c}0), is not 1, as predicted by DSA, but increases with increasing particle energy. The general solution combines both the reconnection-induced electric field and plasmoid contraction. The observed energetic particle intensity profile observed by Voyager 2 downstream of the HTS appears to support a particle acceleration mechanism that combines both DSA and magnetic-island-reconnection-related processes.

  2. Small type accelerator. Try for accelerator driven system

    CERN Document Server

    Mori, Y

    2003-01-01

    FFAG (Fixed-field alternating gradient) accelerator for accelerator driven subcritical reactor, which aims to change from long-lived radioactive waste to short-lived radioactivity, is introduced. It is ring accelerator. The performance needed is proton as accelerator particle, 10MW (total) beam power, about 1GeV beam energy, >30% power efficiency and continuous beam. The feature of FFAG accelerator is constant magnetic field. PoP (Proof-of-principle)-FFAG accelerator, radial type, was run at first in Japan in 2000. The excursion is about some ten cm. In principle, beam can be injected and extracted at any place of ring. The 'multi-fish' acceleration can accelerate beams to 100% duty by repeating acceleration. 150MeV-FFAG accelerator has been started since 2001. It tried to practical use, for example, treatment of cancer. (S.Y.)

  3. Accelerating nondiffracting beams

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Shaohui; Li, Manman; Yao, Baoli, E-mail: yaobl@opt.ac.cn; Yu, Xianghua; Lei, Ming; Dan, Dan; Yang, Yanlong; Min, Junwei; Peng, Tong

    2015-06-05

    We present a set of beams which combine the properties of accelerating beams and (conventional) diffraction-free beams. These beams can travel along a desired trajectory while keeping an approximately invariant transverse profile, which may be (higher-order) Bessel-, Mathieu- or parabolic-nondiffracting-like beams, depending on the initial complex amplitude distribution. A possible application of these beams presented here may be found in optical trapping field. For example, a higher-order Bessel-like beam, which has a hollow (transverse) pattern, is suitable for guiding low-refractive-index or metal particles along a curve. - Highlights: • A set of beams having arbitrary trajectories of accelerating and nondiffracting behaviors are generalized and presented. • Bessel-like accelerating beams are generalized to the higher-order (hollow) version. • Mathieu-like accelerating beams and parabolic-nondiffracting-like accelerating beams are presented. • A possible application of these beams may be found in optical trapping and guiding of particles.

  4. Dielectric laser accelerators

    Science.gov (United States)

    England, R. Joel; Noble, Robert J.; Bane, Karl; Dowell, David H.; Ng, Cho-Kuen; Spencer, James E.; Tantawi, Sami; Wu, Ziran; Byer, Robert L.; Peralta, Edgar; Soong, Ken; Chang, Chia-Ming; Montazeri, Behnam; Wolf, Stephen J.; Cowan, Benjamin; Dawson, Jay; Gai, Wei; Hommelhoff, Peter; Huang, Yen-Chieh; Jing, Chunguang; McGuinness, Christopher; Palmer, Robert B.; Naranjo, Brian; Rosenzweig, James; Travish, Gil; Mizrahi, Amit; Schachter, Levi; Sears, Christopher; Werner, Gregory R.; Yoder, Rodney B.

    2014-10-01

    The use of infrared lasers to power optical-scale lithographically fabricated particle accelerators is a developing area of research that has garnered increasing interest in recent years. The physics and technology of this approach is reviewed, which is referred to as dielectric laser acceleration (DLA). In the DLA scheme operating at typical laser pulse lengths of 0.1 to 1 ps, the laser damage fluences for robust dielectric materials correspond to peak surface electric fields in the GV /m regime. The corresponding accelerating field enhancement represents a potential reduction in active length of the accelerator between 1 and 2 orders of magnitude. Power sources for DLA-based accelerators (lasers) are less costly than microwave sources (klystrons) for equivalent average power levels due to wider availability and private sector investment. Because of the high laser-to-particle coupling efficiency, required pulse energies are consistent with tabletop microJoule class lasers. Combined with the very high (MHz) repetition rates these lasers can provide, the DLA approach appears promising for a variety of applications, including future high-energy physics colliders, compact light sources, and portable medical scanners and radiative therapy machines.

  5. Plasma-based accelerator structures

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Carl B.

    1999-12-01

    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.

  6. Plasma-based accelerator structures

    International Nuclear Information System (INIS)

    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

  7. Superconducting accelerator magnet design

    International Nuclear Information System (INIS)

    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.)

  8. Particle accelerator physics

    CERN Document Server

    Wiedemann, Helmut

    2007-01-01

    Particle Accelerator Physics is an in-depth and comprehensive introduction to the field of high-energy particle acceleration and beam dynamics. Part I gathers the basic tools, recalling the essentials of electrostatics and electrodynamics as well as of particle dynamics in electromagnetic fields. Part II is an extensive primer in beam dynamics, followed in Part III by the introduction and description of the main beam parameters. Part IV is devoted to the treatment of perturbations in beam dynamics. Part V discusses the details of charged particle accleration. Part VI and Part VII introduce the more advanced topics of coupled beam dynamics and the description of very intense beams. Part VIII is an exhaustive treatment of radiation from accelerated charges and introduces important sources of coherent radiation such as synchrotrons and free-electron lasers. Part IX collects the appendices gathering useful mathematical and physical formulae, parameters and units. Solutions to many end-of-chapter problems are give...

  9. 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 ...

  10. Uniform Acceleration in General Relativity

    CERN Document Server

    Friedman, Yaakov

    2016-01-01

    We extend de la Fuente and Romero's defining equation for uniform acceleration in a general curved spacetime from linear acceleration to the full Lorentz covariant uniform acceleration. In a flat spacetime background, we have explicit solutions. We use generalized Fermi-Walker transport to parallel transport the Frenet basis along the trajectory. In flat spacetime, we obtain velocity and acceleration transformations from a uniformly accelerated system to an inertial system. We obtain the time dilation between accelerated clocks. We apply our acceleration transformations to the motion of a charged particle in a constant electromagnetic field and recover the Lorentz-Abraham-Dirac equation.

  11. Nuclear Physics accelerator facilities

    International Nuclear Information System (INIS)

    The Nuclear Physics program requires the existence and effective operation of large and complex accelerator facilities. These facilities provide the variety of projectile beams upon which virtually all experimental nuclear research depends. Their capability determine which experiments can be performed and which cannot. Seven existing accelerator facilities are operated by the Nuclear Physics program as national facilities. These are made available to all the Nation's scientists on the basis of scientific merit and technical feasibility of proposals. The national facilities are the Clinton P. Anderson Meson Physics Facility (LAMPF) at Los Alamos National Laboratory; the Bates Linear Accelerator Center at Massachusetts Institute of Technology; the Bevalac at Lawrence Berkeley Laboratory; the Tandem/AGS Heavy Ion Facility at Brookhaven National Laboratory; the ATLAS facility at Argonne National Laboratory; the 88-Inch Cyclotron at Lawrence Berkeley Laboratory; the Holifield Heavy Ion Research Facility at Oak Ridge National Laboratory. The Nuclear Physics Injector at the Stanford Linear Accelerator Center (SLAC) enables the SLAC facility to provide a limited amount of beam time for nuclear physics research on the same basis as the other national facilities. To complement the national facilities, the Nuclear Physics program supports on-campus accelerators at Duke University, Texas A and M University, the University of Washington, and Yale University. The facility at Duke University, called the Triangle Universities Nuclear Laboratory (TUNL), is jointly staffed by Duke University, North Carolina State University, and the University of North Carolina. These accelerators are operated primarily for the research use of the local university faculty, junior scientists, and graduate students

  12. Microelectromechanical acceleration-sensing apparatus

    Science.gov (United States)

    Lee, Robb M.; Shul, Randy J.; Polosky, Marc A.; Hoke, Darren A.; Vernon, George E.

    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.

  13. Studies of accelerated compact toruses

    International Nuclear Information System (INIS)

    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

  14. Intermittent Sea Level Acceleration

    OpenAIRE

    Olivieri, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia; Spada, G.; Dipartimento di Scienze di Base e Fondamenti, Università di Urbino Carlo Bo, Urbino

    2013-01-01

    Using instrumental observations from the Permanent Service for Mean Sea Level (PSMSL), we provide a new assessment of the global sea{level acceleration for the last 2 centuries (1820-2010). Our results, obtained by a stack of tide gauge time series, con firm the existence of a global sea level acceleration (GSLA) and, coherently with independent assessments so far, they point to a value close to 0:01 mm/yr2. However, di fferently from previous studies, we discuss how change points or ...

  15. Seismic surveying and accelerators

    International Nuclear Information System (INIS)

    The paper deals with an investigation into the impact of earth vibrations on charged particle beams in modern colliders. It is ascertained that the displacement of accelerator magnetic elements from the perfect position results in the excitation of betatron oscillations and distortion of particle orbit position. The results of experimental investigations into seismic noises are presented for ASR, SSC, DESY and KEK. The rms orbit displacement in accelerators is estimated relying on the law of earth diffusion motion, according to which the variance of relative displacements is proportional to the distance between these points and time of observation. 6 refs., 3 figs., 2 tabs

  16. High intensity hadron accelerators

    International Nuclear Information System (INIS)

    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

  17. SPS accelerating cavity

    CERN Multimedia

    1983-01-01

    See photo 8302397: View from the downstream end of one of the SPS accelerating cavities (200 MHz, travelling wave structure). See 7603195 and 8011289 for more details, 7411032 for the travelling wave structure, and also 8104138. Giacomo Primadei stands on the left.

  18. 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.

  19. Hamburg Accelerator Conference

    International Nuclear Information System (INIS)

    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

  20. 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.

  1. The CERN accelerator complex

    CERN Multimedia

    De Melis, Cinzia

    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.

  2. The Bevalac accelerator

    International Nuclear Information System (INIS)

    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

  3. The CERN Accelerator School

    CERN Multimedia

    2016-01-01

      Introduction to accelerator physics This course will take place in Istanbul, Turkey, from 18 to 30 September 2016. It is now open for registration, and further information can be found here: http://cas.web.cern.ch/cas/Turkey-2016/Turkey-advert.html

  4. SPS accelerating cavity

    CERN Multimedia

    1980-01-01

    One of the SPS acceleration cavities (200 MHz, travelling wave structure). On the ceiling one sees the coaxial transmission line which feeds the power from the amplifier, located in a surface building above, to the upstream end of the cavity. See 7603195 for more details, 7411032 for the travelling wave structure, and also 8104138, 8302397.

  5. Accelerators in the sky

    International Nuclear Information System (INIS)

    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.)

  6. 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.

  7. Heavy ion accelerator GANIL

    International Nuclear Information System (INIS)

    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

  8. Superconducting traveling wave accelerators

    International Nuclear Information System (INIS)

    This note considers the applicability of superconductivity to traveling wave accelerators. Unlike CW operation of a superconducting standing wave or circulating wave accelerator section, which requires improvement factors (superconductor conductivity divided by copper conductivity) of about 106 in order to be of practical use, a SUperconducting TRaveling wave Accelerator, SUTRA, operating in the pulsed mode requires improvement factors as low as about 103, which are attainable with niobium or lead at 4.2K, the temperature of liquid helium at atmospheric pressure. Changing from a copper traveling wave accelerator to SUTRA achieves the following. (1) For a given gradient SUTRA reduces the peak and average power requirements typically by a factor of 2. (2) SUTRA reduces the peak power still further because it enables us to increase the filling time and thus trade pulse width for gradient. (3) SUTRA makes possible a reasonably long section at higher frequencies. (4) SUTRA makes possible recirculation without additional rf average power. 8 references, 6 figures, 1 table

  9. SPS accelerating cavity

    CERN Multimedia

    CERN PhotoLab

    1981-01-01

    One of the SPS accelerating cavities (200 MHz, travelling wave structure). The power that is fed into the upstream end of the cavity is extracted at the downstream end and sent into a dump load. See 7603195 for more details, 7411032 for the travelling wave structure, and also 8011289, 8302397.

  10. 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/.

  11. 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

    2016-08-16

    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

  12. Accelerator mass spectrometry programme at Mumbai pelletron accelerator facility

    International Nuclear Information System (INIS)

    The Accelerator Mass Spectrometry (AMS) programme and the related developments based on the Mumbai Pelletron accelerator are described. The initial results of the measurement of the ratio, 36Cl / Cl in water samples are presented. (author)

  13. Accelerator research studies

    International Nuclear Information System (INIS)

    The Accelerator Research Studies program at the University of Maryland, sponsored by the Department of Energy under contract number AC05-85ER40216-8, is currently in the third year of its three-year funding cycle. This Renewal Proposal requests DOE support for the next three-year period from June 1, 1991 to May 31, 1994. It documents the progress made during the past year and outlines the proposed research program for the next three years. The program consisted 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.'' These tasks will be discussed in this paper

  14. Accelerator research studies

    International Nuclear Information System (INIS)

    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

  15. Accelerated Parallel Texture Optimization

    Institute of Scientific and Technical Information of China (English)

    Hao-Da Huang; Xin Tong; Wen-Cheng Wang

    2007-01-01

    Texture optimization is a texture synthesis method that can efficiently reproduce various features of exemplar textures. However, its slow synthesis speed limits its usage in many interactive or real time applications. In this paper, we propose a parallel texture optimization algorithm to run on GPUs. In our algorithm, k-coherence search and principle component analysis (PCA) are used for hardware acceleration, and two acceleration techniques are further developed to speed up our GPU-based texture optimization. With a reasonable precomputation cost, the online synthesis speed of our algorithm is 4000+ times faster than that of the original texture optimization algorithm and thus our algorithm is capable of interactive applications. The advantages of the new scheme are demonstrated by applying it to interactive editing of flow-guided synthesis.

  16. Hardware Accelerated Simulated Radiography

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-04-12

    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. Accelerating QDP++ using GPUs

    CERN Document Server

    Winter, Frank

    2011-01-01

    Graphic Processing Units (GPUs) are getting increasingly important as target architectures in scientific High Performance Computing (HPC). NVIDIA established CUDA as a parallel computing architecture controlling and making use of the compute power of GPUs. CUDA provides sufficient support for C++ language elements to enable the Expression Template (ET) technique in the device memory domain. QDP++ is a C++ vector class library suited for quantum field theory which provides vector data types and expressions and forms the basis of the lattice QCD software suite Chroma. In this work accelerating QDP++ expression evaluation to a GPU was successfully implemented leveraging the ET technique and using Just-In-Time (JIT) compilation. The Portable Expression Template Engine (PETE) and the C API for CUDA kernel arguments were used to build the bridge between host and device memory domains. This provides the possibility to accelerate Chroma routines to a GPU which are typically not subject to special optimisation. As an ...

  18. Accelerator research studies

    International Nuclear Information System (INIS)

    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

  19. 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.

  20. Accelerator research studies

    International Nuclear Information System (INIS)

    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

  1. NEW ACCELERATION METHODS

    Energy Technology Data Exchange (ETDEWEB)

    Sessler, A.M.

    1984-07-01

    But a glance at the Livingston chart, Fig. 1, of accelerator particle energy as a function of time shows that the energy has steadily, exponentially, increased. Equally significant is the fact that this increase is the envelope of diverse technologies. If one is to stay on, or even near, the Livingston curve in future years then new acceleration techniques need to be developed. What are the new acceleration methods? In these two lectures I would like to sketch some of these new ideas. I am well aware that they will probably not result in high energy accelerators within this or the next decade, but conversely, it is likely that these ideas will form the basis for the accelerators of the next century. Anyway, the ideas are stimulating and suffice to show that accelerator physicists are not just 'engineers', but genuine scientists deserving to be welcomed into the company of high energy physicists. I believe that outsiders will find this field surprisingly fertile and, certainly fun. To put it more personally, I very much enjoy working in this field and lecturing on it. There are a number of review articles which should be consulted for references to the original literature. In addition there are three books on the subject. Given this material, I feel free to not completely reference the material in the remainder of this article; consultation of the review articles and books will be adequate as an introduction to the literature for references abound (hundreds are given). At last, by way of introduction, I should like to quote from the end of Ref. 2 for I think the remarks made there are most germane. Remember that the talk was addressed to accelerator physicists: 'Finally, it is often said, I think by physicists who are not well-informed, that accelerator builders have used up their capital and now are bereft of ideas, and as a result, high energy physics will eventually--rather soon, in fact--come to a halt. After all, one can't build too many

  2. RFQ accelerator development

    International Nuclear Information System (INIS)

    Radio frequency quadrupole (RFQ) accelerators have established themselves as highly efficient and potential tools for delivering intense beams of the order of 100 mA or more. They are being employed as injectors to high energy machines used for basic sciences, spallation neutron sources, fusion devices and accelerator breeders. They have also made their mark as neutron generators, ion implanters, x-ray generators, etc. Realising the importance of this programme, Bhabha Atomic Research Centre initiated a totally indigenous effort to develop RFQs for the light as well as heavy ion beams. A low power RFQ for the proton and deuteron beams is already in the final phase of commissioning. (author). 30 refs., 14 figs., 2 tabs

  3. 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...

  4. Accelerators for Cancer Therapy

    Science.gov (United States)

    Lennox, Arlene J.

    2000-05-30

    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.

  5. Particle acceleration by pulsars

    International Nuclear Information System (INIS)

    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

  6. GPU accelerated face detection

    OpenAIRE

    Mäkelä, J.

    2013-01-01

    Graphics processing units have massive parallel processing capabilities, and there is a growing interest in utilizing them for generic computing. One area of interest is computationally heavy computer vision algorithms, such as face detection and recognition. Face detection is used in a variety of applications, for example the autofocus on cameras, face and emotion recognition, and access control. In this thesis, the face detection algorithm was accelerated with GPU using OpenCL. The goal was...

  7. Accelerator Experiments for Astrophysics

    OpenAIRE

    Ng, Johnny S. T.

    2003-01-01

    Many recent discoveries in astrophysics involve phenomena that are highly complex. Carefully designed experiments, together with sophisticated computer simulations, are required to gain insights into the underlying physics. We show that particle accelerators are unique tools in this area of research, by providing precision calibration data and by creating extreme experimental conditions relevant for astrophysics. In this paper we discuss laboratory experiments that can be carried out at the S...

  8. Compact pulsed accelerator

    International Nuclear Information System (INIS)

    The formation of fast pulses from a current charged transmission line and opening switch is described. By employing a plasma focus as an opening switch and diode in the prototype device, a proton beam of peak energy 250 keV is produced. The time integrated energy spectrum of the beam is constructed from a Thomson spectrograph. Applications of this device as an inexpensive and portable charged particle accelerator are discussed. 7 refs., 5 figs., 1 tab

  9. Laser plasma accelerators

    OpenAIRE

    Malka, V.

    2012-01-01

    Research activities on laser plasma accelerators are paved by many significant breakthroughs. This review article provides an opportunity to show the incredible evolution of this field of research which has, in record time, allowed physicists to produce high quality electron beams at the GeV level using compact laser systems. I will show the scientific path that led us to explore different injection schemes and to produce stable, high peak current and high quality electron beams with control ...

  10. 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.

  11. Accelerated plate tectonics.

    Science.gov (United States)

    Anderson, D L

    1975-03-21

    The concept of a stressed elastic lithospheric plate riding on a viscous asthenosphere is used to calculate the recurrence interval of great earthquakes at convergent plate boundaries, the separation of decoupling and lithospheric earthquakes, and the migration pattern of large earthquakes along an arc. It is proposed that plate motions accelerate after great decoupling earthquakes and that most of the observed plate motions occur during short periods of time, separated by periods of relative quiescence.

  12. Future Accelerator Magnet Needs

    CERN Document Server

    Devred, Arnaud; Yamamoto, A

    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&D programs in the EU, Japan and the USA. A performance comparison between NbTi and Nb3Sn along with fabrication and cost issues are also discussed.

  13. Shock accelerated vortex ring

    CERN Document Server

    Haehn, N; Oakley, J; Anderson, M; Rothamer, D; Bonazza, R

    2009-01-01

    The interaction of a shock wave with a spherical density inhomogeneity leads to the development of a vortex ring through the impulsive deposition of baroclinic vorticity. The present fluid dynamics videos display this phenomenon and were experimentally investigated at the Wisconsin Shock Tube Laboratory's (WiSTL) 9.2 m, downward firing shock tube. The tube has a square internal cross-section (0.25 m x 0.25 m) with multiple fused silica windows for optical access. The spherical soap bubble is generated by means of a pneumatically retracted injector and released into free-fall 200 ms prior to initial shock acceleration. The downward moving, M = 2.07 shock wave impulsively accelerates the bubble and reflects off the tube end wall. The reflected shock wave re-accelerates the bubble (reshock), which has now developed into a vortex ring, depositing additional vorticity. In the absence of any flow disturbances, the flow behind the reflected shock wave is stationary. As a result, any observed motion of the vortex rin...

  14. 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.

  15. 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...

  16. Accelerated GLAS exposure station

    International Nuclear Information System (INIS)

    The Geoscience Laser Altimeter System (GLAS) is being developed by NASA/GSFC to measure the dynamics of the ice sheet mass balance, land, and cloud and atmospheric properties. An instrument altimetric resolution of 10 cm per shot is required. The laser transmitter will be a diode pumped, Q-switched, Nd:YAG laser producing 1064 nm, 100 mJ, 4 ns pulses at 40 Hz repetition rate in a TEM∞ mode. A minimum lifetime goal of 2 billion shots is required per laser transmitter. The performance of the GLAS laser can be limited by physical damage to the optical components caused by the interaction of intense laser energy with the optical coatings and substrates. Very little data exists describing the effects of long duration laser exposure, of 4 ns pulses, on an optical component. An Accelerated GLAS Exposure Station (AGES) is being developed which will autonomously operate and monitor the GLAS laser at an accelerated rate of 500 Hz. The effects of a large number of laser shots will be recorded. Parameters to be monitored include: laser power, pulsewidth, beam size, laser diode drive current and power, Q-switch drive voltage, temperature, and humidity. For comparison, one set of AGES-sister optical components will be used in the non-accelerated GLAS laser and another will be evaluated by a commercial optical damage test facility

  17. Linac transport and acceleration

    International Nuclear Information System (INIS)

    The acceleration of intense bunches maintaining high brightness is limited both by single-particle effects, e.g., misalignments, injection errors, and rf-steering, and collective phenomena, where the effects of the longitudinal and transverse wakefield on particles within a single bunch are the most severe. The working group has considered both problems and potentials of linac acceleration from ∼50 MeV to 1 GeV for free electron laser (FEL) applications, as well as from a few Gev to 1 TeV for linear colliders. The outlook for free electron lasers is bright: no fundamental problems seem to arise in the acceleration of peak currents in excess of 100 A with small emittance and low momentum spread. The situation of linear colliders is more complex and more difficult. Two examples, one operating at 11.4 GHz, the other at 30 GHz, are used to illustrate some of the difficulties and the exceedingly tight tolerances required. Both examples are based on round beams, and thus neither benefit from the advantages of flat beams nor address the increased care required in transporting beams of very small emittance in one plane. The working group acknowledges, but did not explore, promising concepts for colliders based on RF superconductivity

  18. Acceleration during magnetic reconnection

    Energy Technology Data Exchange (ETDEWEB)

    Beresnyak, Andrey [Los Alamos National Laboratory; Li, Hui [Los Alamos National Laboratory

    2015-07-16

    The presentation begins with colorful depictions of solar x-ray flares and references to pulsar phenomena. Plasma reconnection is complex, could be x-point dominated or turbulent, field lines could break due to either resistivity or non-ideal effects, such as electron pressure anisotropy. Electron acceleration is sometimes observed, and sometimes not. One way to study this complex problem is to have many examples of the process (reconnection) and compare them; the other way is to simplify and come to something robust. Ideal MHD (E=0) turbulence driven by magnetic energy is assumed, and the first-order acceleration is sought. It is found that dissipation in big (length >100 ion skin depths) current sheets is universal and independent on microscopic resistivity and the mean imposed field; particles are regularly accelerated while experiencing curvature drift in flows driven by magnetic tension. One example of such flow is spontaneous reconnection. This explains hot electrons with a power-law tail in solar flares, as well as ultrashort time variability in some astrophysical sources.

  19. Laser driven particle acceleration

    International Nuclear Information System (INIS)

    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)

  20. 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.

  1. CESR Test Accelerator

    CERN Document Server

    Rubin, David L

    2013-01-01

    The Cornell Electron Storage Ring (CESR) was reconfigured in 2008 as a test accelerator to investigate the physics of ultra-low emittance damping rings. During the approximately 40 days/year available for dedicated operation as a test accelerator, specialized instrumentation is used to measure growth and mitigation of the electron cloud, emittance growth due to electron cloud, intra-beam scattering, and ions, and single and multi-bunch instabilities generated by collective effects. The flexibility of the CESR guide field optics and the integration of accelerator modeling codes with the control system have made possible an extraordinary range of experiments. Findings at CesrTA with respect to electron cloud effects, emittance tuning techniques, and beam instrumentation for measuring electron cloud, beam sizes, and beam positions are the basis for much of the design of the ILC damping rings as documented in the ILC-Technical Design Report. The program has allowed the Cornell group to cultivate the kind of talen...

  2. Laser-driven electron accelerators

    International Nuclear Information System (INIS)

    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

  3. Electron accelerators for environmental protection

    International Nuclear Information System (INIS)

    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 SO2 and NOx 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 direct

  4. Accelerating in de Sitter spacetimes

    CERN Document Server

    Cotaescu, Ion I

    2014-01-01

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

  5. APT accelerator. Topical report

    International Nuclear Information System (INIS)

    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

  6. 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.

  7. 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.

  8. 2014 CERN Accelerator Schools

    CERN Multimedia

    2014-01-01

    A specialised school on Power Converters will be held in Baden, Switzerland, from 7 to 14 May 2014. Please note that the deadline for applications is 7 FEBRUARY 2014. A course on Introduction to Accelerator Physics will be held in Prague, Czech Republic, from 31 August to 12 September 2014. Applications are now open for this school; the application deadline is 25 APRIL 2014. Further information on these schools and other CAS events can be found on the CAS website and on the Indico page. For further information please contact Barbara.strasser@cern.ch

  9. Accelerating abelian gauge dynamics

    CERN Document Server

    Adler, Stephen Louis

    1991-01-01

    In this paper, we suggest a new acceleration method for Abelian gauge theories based on linear transformations to variables which weight all length scales equally. We measure the autocorrelation time for the Polyakov loop and the plaquette at β=1.0 in the U(1) gauge theory in four dimensions, for the new method and for standard Metropolis updates. We find a dramatic improvement for the new method over the Metropolis method. Computing the critical exponent z for the new method remains an important open issue.

  10. 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.

  11. Hardware Accelerated Power Estimation

    CERN Document Server

    Coburn, Joel; Raghunathan, Anand

    2011-01-01

    In this paper, we present power emulation, a novel design paradigm that utilizes hardware acceleration for the purpose of fast power estimation. Power emulation is based on the observation that the functions necessary for power estimation (power model evaluation, aggregation, etc.) can be implemented as hardware circuits. Therefore, we can enhance any given design with "power estimation hardware", map it to a prototyping platform, and exercise it with any given test stimuli to obtain power consumption estimates. Our empirical studies with industrial designs reveal that power emulation can achieve significant speedups (10X to 500X) over state-of-the-art commercial register-transfer level (RTL) power estimation tools.

  12. 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.

  13. Acceleration without Temperature

    CERN Document Server

    Doria, Alaric

    2015-01-01

    We show that while some non-uniformly accelerating observers (NUAOs) do indeed see a Bose-Einstein distribution of particles for the expectation value of the number operator in the Minkowski vacuum state, the density matrix is non-thermal and therefore a definition of temperature is not warranted. This is due to the fact that our NUAOs do not see event horizons in the spacetime. More specifically, the Minkowski vacuum state is perceived by our NUAOs as a single-mode squeezed state as opposed to the two-mode squeezed state characteristic of uniformly accelerating observers. Both single and two-mode squeezed states are pure quantum states; however, tracing over degrees of freedom in one of the modes of the two-mode squeezed state reduces the pure density matrix to a thermal density matrix. It is this property in the two-mode squeezed state that allows one to consistently define a temperature. In the single-mode case, an equivalent tracing is neither required nor available.

  14. Accelerator School Success

    CERN Document Server

    2004-01-01

    Accelerator specialists don't grow on trees: training them is the job of the CERN Accelerator School (CAS). Group photo during visit to the Daresbury Laboratory. CAS and the CCLRC Daresbury Laboratory jointly organised a specialised school on Power Converters in Warrington, England from 12-18 May 2004. The last CAS Power Converter course was in 1990, so there was plenty of ground to cover. The challenging programme proposed a review of the state of the art and the latest developments in the field, including 30 hours of tuition. The school also included a visit to the CCLRC Daresbury laboratory, a one-day excursion to Liverpool and Chester and a themed (Welsh medieval) dinner at the school's closure. A record attendance of 91 students of more than 20 different nationalities included not only participants from Europe and North America but also from Armenia, Taiwan, India, Turkey, Iran and for the first time, fee-paying students from China and Australia. European industry showed a welcome and solid interest in...

  15. 2014 Joint International Accelerator School: Beam Loss and Accelerator Protection

    CERN Document Server

    JAS - Joint US-CERN-Japan-Russia Accelerator School

    2016-01-01

    Many particle accelerators operate with very high beam power and very high energy stored in particle beams as well as in magnet systems. In the future, the beam power in high intensity accelerators will further increase. The protection of the accelerator equipment from the consequences of uncontrolled release of the energy is essential. This was the motivation for organizing a first school on beam losses and accelerator protection (in general referred to as machine protection). During the school the methods and technologies to identify, mitigate, monitor and manage the technical risks associated with the operation of accelerators with high-power beams or subsystems with large stored energy were presented. At the completion of the school the participants should have been able to understand the physical phenomena that can damage machine subsystems or interrupt operations and to analyze an accelerator facility to produce a register of technical risks and the corresponding risk mitigation and management strategie...

  16. Accelerator Technology: Geodesy and Alignment for Particle Accelerators

    CERN Document Server

    Missiaen, D

    2013-01-01

    This document is part of Subvolume C 'Accelerators and Colliders' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the the Section '8.9 Geodesy and Alignment for Particle Accelerators' of the Chapter '8 Accelerator Technology' with the content: 8.9 Geodesy and Alignment for Particle Accelerators 8.9.1 Introduction 8.9.2 Reference and Co-ordinate Systems 8.9.3 Definition of the Beam Line on the Accelerator Site 8.9.4 Geodetic Network 8.9.5 Tunnel Preliminary Works 8.9.6 The Alignment References 8.9.7 Alignment of Accelerator Components 8.9.8 Permanent Monitoring and Remote Alignment of Low Beta Quadrupoles 8.9.9 Alignment of Detector Components

  17. Acceleration in Linear and Circular Motion

    Science.gov (United States)

    Kellington, S. H.; Docherty, W.

    1975-01-01

    Describes the construction of a simple accelerometer and explains its use in demonstrating acceleration, deceleration, constant speed, measurement of acceleration, acceleration and the inclined plane and angular and radial acceleration. (GS)

  18. Investigation on laser accelerators. Plasma beat wave accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Miura, Akihiko; Miyamoto, Yasuaki; Hagiwara, Masayoshi; Suzuki, Mitsutoshi; Sudo, Osamu [Power Reactor and Nuclear Fuel Development Corp., Tokai, Ibaraki (Japan). Tokai Works

    1998-04-01

    Laser accelerator technology has characteristics of high energy, compact, short pulse and high luminescence{center_dot}low emittance. This means potential many applications in wide ranges of fields as well as high energy and nuclear physics. High power short laser pulses are injected to a plasma in the typical example of laser accelerators. Large electric fields are induced in the plasma. Electrons in the plasma are accelerated with the ponderomotive force of the electric field. The principles of interaction on beat wave, wakefield accelerators, inverse free electron laser and inverse Cherenkov radiation are briefly introduced. The overview of plasma beat wave accelerator study is briefly described on the programs at Chalk River Laboratories(Canada), UCLA(USA), Osaka Univ. (Japan) and Ecole Polytechnique (France). Issues of the plasma beat wave accelerator are discussed from the viewpoint of application. Existing laser technologies of CO{sub 2}, YAG and YFL are available for the present day accelerator technology. An acceleration length of beat wave interaction is limited due to its phase condition. Ideas on multi-staged acceleration using the phasing plasma fiber are introduced. (Y. Tanaka)

  19. CAS CERN Accelerator School: Advanced accelerator physics. Proceedings. Vol. 1

    International Nuclear Information System (INIS)

    This advanced course on general accelerator physics is the second of the biennial series given by the CERN Accelerator School and follows on from the first basic course given at Gif-sur-Yvette, Paris, in 1984. Stress is placed on the mathematical tools of Hamiltonian mechanics and the Vlasov and Fokker-Planck equations, which are widely used in accelerator theory. The main topics treated in this present work include: nonlinear resonances, chromaticity, motion in longitudinal phase space, growth and control of longitudinal and transverse beam emittance, space-charge effects and polarization. The seminar programme treats some specific accelerator techniques, devices, projects and future possibilities. (orig.)

  20. CERN Accelerator School: Registration open for Advanced Accelerator Physics course

    CERN Multimedia

    2015-01-01

    Registration is now open for the CERN Accelerator School’s Advanced Accelerator Physics course to be held in Warsaw, Poland from 27 September to 9 October 2015.   The course will be of interest to physicists and engineers who wish to extend their knowledge of accelerator physics. The programme offers core lectures on accelerator physics in the mornings and a practical course with hands-on tuition in the afternoons.  Further information can be found at: http://cas.web.cern.ch/cas/Poland2015/Warsaw-advert.html http://indico.cern.ch/event/361988/

  1. CERN Accelerator School: Registration open for Advanced Accelerator Physics course

    CERN Multimedia

    2015-01-01

    Registration is now open for the CERN Accelerator School’s Advanced Accelerator Physics course to be held in Warsaw, Poland from 27 September to 9 October 2015.   The course will be of interest to physicists and engineers who wish to extend their knowledge of Accelerator Physics. The programme offers core lectures on accelerator physics in the mornings and a practical course with hands-on tuition in the afternoons.  Further information can be found at: http://cas.web.cern.ch/cas/Poland2015/Warsaw-advert.html http://indico.cern.ch/event/361988/

  2. CAS CERN Accelerator School: Advanced accelerator physics. Proceedings. Vol. 2

    International Nuclear Information System (INIS)

    This advanced course on general accelerator physics is the second of the biennial series given by the CERN Accelerator School and follows on from the first basic course given at Gif-sur-Yvette, Paris, in 1984. Stress is placed on the mathematical tools of Hamiltonian mechanics and the Vlasov and Fokker-Planck equations, which are widely used in accelerator theory. The main topics treated in this present work include: nonlinear resonances, chromaticity, motion in longitudinal phase space, growth and control of longitudinal and transverse beam emittance, space-charge effects and polarization. The seminar programme treats some specific accelerator techniques, devices, projects and future possibilities. (orig.)

  3. Lectures in accelerator theory

    International Nuclear Information System (INIS)

    Lecture I deals with the behavior of particles in the nonlinear field arising from the electromagnetic interaction of colliding beams. The case treated, that of counter-rotating proton beams crossing each other at a non-zero angle, has the simple feature that the force between the beam is one dimensional. In lecture II, an analysis of the development of traveling waves on particle beams is presented. The situation studied is that of a uniform beam current in a circular accelerator and the excitation for the coherent motion is induced by the resistivity of the vacuum chamber wall. Finally, in lecture III, a description of the current accumulation process used at the proton storage rings at CERN (The ISR) is given. Particle pulses of rather low average current are injected and stored along the length and width of the vacuum chamber. The efficiency is very high and large currents (over 40 amperes) have been achieved

  4. Accelerator vacuum system elements

    International Nuclear Information System (INIS)

    Some elements of vacuum systems are investigated. Considerable attention has been given to the investigation into peculiarities in pumping out of a ionoguide for transportation of an accelerated charged particles beam the spread of which often attains a considerable length. The number of pumps over the ionoguide length is experimentally determined. It is shown that as a result of ionoguide warm-up the pumping out time is considerably reduced maximum permissible pressure is decreased by two orders and lesser rate of pump pumping out is required. The investigations have shown that when operating the ionoguide there is no necessity in setting up seals between the ionoguide and magnetodischarged pump. The causes of the phenomenon in which the pressure near the pump is greater than in the end of the ionoguide, are impurities carried in by the pump into the ionoguide volume and the pumping out capacity of the pressure converter

  5. 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...... for the different elements of the TIS to evolve. This could involve nano-visioning including scenarios of future technological applications and industrial dynamics....

  6. Testing Gravity on Accelerators

    CERN Document Server

    Kalaydzhyan, Tigran

    2016-01-01

    Weak equivalence principle (WEP) is one of the cornerstones of the modern theories of gravity, stating that the trajectory of a freely falling test body is independent of its internal structure and composition. Even though WEP is known to be valid for the normal matter with a high precision, it has never been experimentally confirmed for relativistic matter and antimatter. We make an attempt to constrain possible deviations from WEP utilizing the modern accelerator technologies. We analyze the (absence of) vacuum Cherenkov radiation, photon decay, anomalous synchrotron losses and the Compton spectra to put limits on the isotropic Lorentz violation and further convert them to the constraints on the difference between the gravitational and inertial masses of the relativistic electrons/positrons. Our main result is the 0.1% limit on the mentioned difference.

  7. Self-accelerated Universe

    CERN Document Server

    Kosyakov, B P

    2005-01-01

    It is widely believed that the large redshifts for distant supernovae are explained by the vacuum energy dominance, or, in other words, by the cosmological constant in Einstein's equations, which is responsible for the anti-gravitation effect. A tacit assumption is that particles move along a geodesic for the background metric. This is in the same spirit as the consensus regarding the uniform Galilean motion of a free electron. However, there is a runaway solution to the Lorentz--Dirac equation governing the behavior of a radiating electron, in addition to the Galilean solution. Likewise, a runaway solution to the entire system of equations, both gravitation and matter equations of motion including, may provide an alternative explanation for the accelerated expansion of the Universe, without recourse to the hypothetic cosmological constant.

  8. The entangled accelerating universe

    CERN Document Server

    González-Díaz, Pedro F

    2009-01-01

    Using the known result that the nucleation of baby universes in correlated pairs is equivalent to spacetime squeezing, we show in this letter that there exists a T-duality symmetry between two-dimensional warp drives, which are physically expressible as localized de Sitter little universes, and two dimensional Tolman-Hawking and Gidding-Strominger baby universes respectively correlated in pairs, so that the creation of warp drives is also equivalent to spacetime squeezing. Perhaps more importantly, it has been also seen that the nucleation of warp drives entails a violation of the Bell's inequalities, and hence the phenomena of quantum entanglement, complementarity and wave function collapse. These results are generalized to the case of any dynamically accelerating universe filled with dark or phantom energy whose creation is also physically equivalent to spacetime squeezing and to the violation of the Bell's inequalities, so that the universe we are living in should be governed by essential sharp quantum the...

  9. SPS accelerating cavity

    CERN Multimedia

    1976-01-01

    The SPS started up with 2 accelerating cavities (each consisting of 5 tank sections) in LSS3. They have a 200 MHz travelling wave structure (see 7411032 and 7802190) and 750 kW of power is fed to each of the cavities from a 1 MW tetrode power amplifier, located in a surface building above, via a coaxial transmission line. Clemens Zettler, builder of the SPS RF system, is standing at the side of one of the cavities. In 1978 and 1979 another 2 cavities were added and entered service in 1980. These were part of the intensity improvement programme and served well for the new role of the SPS as proton-antiproton collider. See also 7411032, 8011289, 8104138, 8302397.

  10. Accelerator Technology for the Mankind

    CERN Document Server

    Sultansoy, S

    2006-01-01

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

  11. Electrostatic accelerators fundamentals and applications

    CERN Document Server

    2005-01-01

    Electrostatic accelerators are an important and widespread subgroup within the broad spectrum of modern, large particle acceleration devices. They are specifically designed for applications that require high-quality ion beams in terms of energy stability and emittance at comparatively low energies (a few MeV). Their ability to accelerate virtually any kind of ion over a continuously tunable range of energies make them a highly versatile tool for investigations in many research fields including, but not limited to, atomic and nuclear spectroscopy, heavy ion reactions, accelerator mass spectroscopy as well as ion-beam analysis and modification. The book is divided into three parts. The first part concisely introduces the field of accelerator technology and techniques that emphasize their major modern applications. The second part treats the electrostatic accelerator per se: its construction and operational principles as well as its maintenance. The third part covers all relevant applications in which electrosta...

  12. Accelerating Universe and Event Horizon

    OpenAIRE

    He, Xiao-Gang(INPAC, SKLPPC and Department of Physics, Shanghai Jiao Tong University, Shanghai, China)

    2001-01-01

    It has been argued in the literature that if a universe is expanding with an accelerating rate indefinitely, it presents a challenge to string theories due to the existence of event horizons. We study the fate of a currently accelerating universe. We show that the universe will continue to accelerate indefinitely if the parameter $\\omega = p/\\rho$ of the equation of state is a constant, no matter how many different types of energy (matter, radiation, quintessence, cosmological constant and et...

  13. Project X: Accelerator Reference Design

    CERN Document Server

    Holmes, S D; Chase, B; Gollwitzer, K; Johnson, D; Kaducak, M; Klebaner, A; Kourbanis, I; Lebedev, V; Leveling, A; Li, D; Nagaitsev, S; Ostroumov, P; Pasquinelli, R; Patrick, J; Prost, L; Scarpine, V; Shemyakin, A; Solyak, N; Steimel, J; Yakovlev, V; Zwaska, R

    2013-01-01

    Part 1 of "Project X: Accelerator Reference Design, Physics Opportunities, Broader Impacts". Part 1 contains the volume Preface and a description of the conceptual design for a high-intensity proton accelerator facility being developed to support a world-leading program of Intensity Frontier physics over the next two decades at Fermilab. Subjects covered include performance goals, the accelerator physics design, and the technological basis for such a facility.

  14. Stationary plasma accelerator - ATON engine

    International Nuclear Information System (INIS)

    The principles of a stationary plasma accelerator (engine) with closed electron drift are described. The accelerator has record integral characteristics. A method for analysis of operating process features in the integral characteristics is proposed. Results are presented of local measurements of the plasma parameters in the accelerator channel and in the leaving plasma jet Main attention is paid to determination of the part of twice ionized ions in the plasma flow

  15. Accelerator control systems in China

    International Nuclear Information System (INIS)

    Three accelerator facilities were built in the past few years, the 2.8 GeV electron positron collider BEPC, the heavy ion SSC cyclotron accelerator HIRFL and the 800 MeV synchrotron radiation storage ring HESYRL. Aimed at different research areas, they represent a new generation of accelerator in China. This report describes the design philosophy, the structure, performance as well as future improvements of the control systems of the these facilities. (author)

  16. Accelerator science in medical physics

    OpenAIRE

    Peach, K.; Wilson, P.; Jones, B

    2011-01-01

    The use of cyclotrons and synchrotrons to accelerate charged particles in hospital settings for the purpose of cancer therapy is increasing. Consequently, there is a growing demand from medical physicists, radiographers, physicians and oncologists for articles that explain the basic physical concepts of these technologies. There are unique advantages and disadvantages to all methods of acceleration. Several promising alternative methods of accelerating particles also have to be considered sin...

  17. Superposed-laser electron acceleration

    International Nuclear Information System (INIS)

    A new mechanism is proposed for electron acceleration by using two superposed laser beams in vacuum. In this mechanism, an electron is accelerated by the longitudinal component of the wave electric field in the overlapped region of two laser beams. Single-particle computations and analytical works are performed in order to demonstrate the viability. These results show that the electron can be accelerated well in this proposed mechanism. (author)

  18. Accelerators for research and applications

    International Nuclear Information System (INIS)

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

  19. Maximal acceleration and radiative processes

    OpenAIRE

    Papini, Giorgio

    2015-01-01

    We derive the radiation characteristics of an accelerated, charged particle in a model due to Caianiello in which the proper acceleration of a particle of mass $m$ has the upper limit $\\mathcal{A}_m=2mc^3/\\hbar$. We find two power laws, one applicable to lower accelerations, the other more suitable for accelerations closer to $\\mathcal{A}_m$ and to the related physical singularity in the Ricci scalar. Geometrical constraints and power spectra are also discussed. By comparing the power laws du...

  20. Thomas Precession by Uniform Acceleration

    CERN Document Server

    Pardy, Miroslav

    2015-01-01

    We determine the nonlinear transformations between coordinate systems which are mutually in a constant symmetrical accelerated motion. The maximal acceleration limit follows from the kinematical origin and it is an analogue of the maximal velocity in special relativity. We derive the dependence of mass, length, time, Doppler effect, Cherenkov effect and transition radiation angle on acceleration as an analogue phenomena in special theory of relativity. The last application of our method is the Thomas precession by uniform acceleration with the possible role in the modern physics and cosmology. The comparison of derived results with other relativistic methods is necessary.

  1. Superconducting Radiofrequency (SRF) Acceleration Technology

    Data.gov (United States)

    Federal Laboratory Consortium — SRF cavities enable accelerators to increase particle beam energy levels while minimizing the use of electrical power by all but eliminating electrical resistance....

  2. CAS CERN Accelerator School: Second general accelerator physics course

    International Nuclear Information System (INIS)

    The course on general accelerator physics given at Aarhus is basically a repeat of that organised by the CERN Accelerator School at Gif-sur-Yvette, Paris in September 1984 and whose proceedings were published as CERN Yellow Report 85-19 (1985). However, the opportunity was taken to improve or extend certain subjects while introducing new ones and it is these which are included in the present proceedings. The lectures treated here include accelerator optics, insertions, image and space charge forces, neutralisation, diagnostics and intra-beam scattering while the seminar programme includes a number of specialised accelerator topics. Reports on a separate series of seminars organised by the University of Aarhus, Denmark, and devoted to advanced technology arising from general accelerator physics are also included, as well as errata to CERN 85-19. (orig.)

  3. CAS CERN Accelerator School superconductivity in particle accelerators

    International Nuclear Information System (INIS)

    One of the objectives of the CERN Accelerator School is to run courses on specialised topics in the particle accelerator field. The present volume contains the proceedings of one such course, this time organized in conjunction with the Deutsches Elektronen Synchrotron (DESY) on the subject of superconductivity in particle accelerators. This course reflects the very considerable progress made over the last few years in the use of the technology for the magnet and radio-frequency systems of many large and small accelerators already in use or nearing completion, while also taking account of the development work now going on for future machines. The lectures cover the theory of superconductivity, cryogenics and accelerator magnets and cavities, while the seminars include superfluidity, superconductors, special magnets and the prospects for high-temperature superconductors. (orig.)

  4. COMPASS Accelerator Design Technical Overview

    Energy Technology Data Exchange (ETDEWEB)

    Nanni, Emilio; Dolgashev, Valery; Tantawi, Sami; Neilson, Jeff; /SLAC

    2016-03-14

    This report is a survey of technical options for generating a MeV-class accelerator for space based science applications. The survey was performed focusing on the primary technical requirements of the accelerator in the context of a satellite environment with its unique challenges of limited electrical power (PE), thermal isolation, dimensions, payload requirement and electrical isolation.

  5. Correct and efficient accelerator programming

    OpenAIRE

    Cohen, Albert; Donaldson, Alistair F.; Huisman, Marieke; Katoen, Joost-Pieter

    2013-01-01

    This report documents the program and the outcomes of Dagstuhl Seminar 13142 “Correct and Efficient Accelerator Programming”. The aim of this Dagstuhl seminar was to bring together researchers from various sub-disciplines of computer science to brainstorm and discuss the theoretical foundations, design and implementation of techniques and tools for correct and efficient accelerator programming.

  6. Software for virtual accelerator designing

    International Nuclear Information System (INIS)

    The article discusses appropriate technologies for software implementation of the Virtual Accelerator. The Virtual Accelerator is considered as a set of services and tools enabling transparent execution of computational software for modeling beam dynamics in accelerators on distributed computing resources. Distributed storage and information processing facilities utilized by the Virtual Accelerator make use of the Service-Oriented Architecture (SOA) according to a cloud computing paradigm. Control system tool-kits (such as EPICS, TANGO), computing modules (including high-performance computing), realization of the GUI with existing frameworks and visualization of the data are discussed in the paper. The presented research consists of software analysis for realization of interaction between all levels of the Virtual Accelerator and some samples of middle-ware implementation. A set of the servers and clusters at St.-Petersburg State University form the infrastructure of the computing environment for Virtual Accelerator design. Usage of component-oriented technology for realization of Virtual Accelerator levels interaction is proposed. The article concludes with an overview and substantiation of a choice of technologies that will be used for design and implementation of the Virtual Accelerator. (authors)

  7. Shadows of a maximal acceleration

    OpenAIRE

    Papini, G.

    2002-01-01

    A quantum mechanical upper limit on the value of particle accelerations, or maximal acceleration (MA), is applied to compact stars. A few MA fermions are at most present in canonical white dwarfs and neutron stars. They drastically alter a star's stability conditions.

  8. Shadows of a maximal acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Papini, G

    2002-12-16

    A quantum mechanical upper limit on the value of particle accelerations, or maximal acceleration (MA), is applied to compact stars. A few MA fermions are at most present in canonical white dwarfs and neutron stars. They drastically alter a star's stability conditions.

  9. Lorentz contraction and accelerated systems

    OpenAIRE

    Tartaglia, Angelo; Ruggiero, Matteo Luca

    2003-01-01

    The paper discusses the problem of the Lorentz contraction in accelerated systems, in the context of the special theory of relativity. Equal proper accelerations along different world lines are considered, showing the differences arising when the world lines correspond to physically connected or disconnected objects. In all cases the special theory of relativity proves to be completely self-consistent

  10. Thomas Edison Accelerated Elementary School.

    Science.gov (United States)

    Levin, Henry M.; Chasin, Gene

    This paper describes early outcomes of a Sacramento, California, elementary school that participated in the Accelerated Schools Project. The school, which serves many minority and poor students, began training for the project in 1992. Accelerated Schools were designed to advance the learning rate of students through a gifted and talented approach,…

  11. New directions in linear accelerators

    International Nuclear Information System (INIS)

    Current work on linear particle accelerators is placed in historical and physics contexts, and applications driving the state of the art are discussed. Future needs and the ways they may force development are outlined in terms of exciting R and D challenges presented to today's accelerator designers. 23 references, 7 figures

  12. Accelerator technology for the mankind

    International Nuclear Information System (INIS)

    Full text: Particle accelerators technology is one of the generic technologies which is locomotive of the development in almost all fields of science and technology. According to the U. S. Department of Energy: Accelerators underpin every activity of the Office of Science and, increasingly, of the entire scientific enterprise. From biology to medicine, from materials to metallurgy, from elementary particles to the cosmos, accelerators provide the microscopic information that forms the basis for scientific understanding and applications. The combination of ground and satellite based observatories and particle accelerators will advance our understanding of our world, our galaxy, our universe, and ourselves. Because of this, accelerator technology should become widespread all over the world. Existing situation shows that a large portion of the world, namely the South and Mid-East, is poor on the accelerator technology. UNESCO has recognized this deficit and started SESAME project in Mid-East, namely Jordan. Turkic Accelerator Complex (TAC) project is more comprehensive and ambitious project, from the point of view of it includes light sources, particle physics experiments and proton and secondary beam applications. At this stage, TAC project includes: Linac-ring type charm factory; Synchrotron light source based on positron ring; Free electron laser based on electron linac; GeV scale proton accelerator; TAC-Test Facility

  13. Analysis of Accelerated Gossip Algorithms

    NARCIS (Netherlands)

    Liu, J.; Anderson, B.D.O.; Cao, M.; Morse, A.S.

    2009-01-01

    This paper investigates accelerated gossip algorithms for distributed computations in networks where shift-registers are utilized at each node. By using tools from matrix analysis, we prove the existence of the desired acceleration and establish the fastest rate of convergence in expectation for two

  14. The entangled accelerating universe

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Diaz, Pedro F. [Colina de los Chopos, Instituto de Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid (Spain); Estacion Ecologica de Biocosmologia, Pedro de Alvarado, 14, 06411-Medellin (Spain)], E-mail: p.gonzalezdiaz@imaff.cfmac.csic.es; Robles-Perez, Salvador [Colina de los Chopos, Instituto de Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid (Spain); Estacion Ecologica de Biocosmologia, Pedro de Alvarado, 14, 06411-Medellin (Spain)

    2009-08-31

    Using the known result that the nucleation of baby universes in correlated pairs is equivalent to spacetime squeezing, we show in this Letter that there exists a T-duality symmetry between two-dimensional warp drives, which are physically expressible as localized de Sitter little universes, and two-dimensional Tolman-Hawking and Gidding-Strominger baby universes respectively correlated in pairs, so that the creation of warp drives is also equivalent to spacetime squeezing. Perhaps more importantly, it has been also seen that the nucleation of warp drives entails a violation of the Bell's inequalities, and hence the phenomena of quantum entanglement, complementarity and wave function collapse. These results are generalized to the case of any dynamically accelerating universe filled with dark or phantom energy whose creation is also physically equivalent to spacetime squeezing and to the violation of the Bell's inequalities, so that the universe we are living in should be governed by essential sharp quantum theory laws and must be a quantum entangled system.

  15. Actinides, accelerators and erosion

    Science.gov (United States)

    Tims, S. G.; Fifield, L. K.

    2012-10-01

    Fallout isotopes can be used as artificial tracers of soil erosion and sediment accumulation. The most commonly used isotope to date has been 137Cs. Concentrations of 137Cs are, however, significantly lower in the Southern Hemisphere, and furthermore have now declined to 35% of original values due to radioactive decay. As a consequence the future utility of 137Cs is limited in Australia, with many erosion applications becoming untenable within the next 20 years, and there is a need to replace it with another tracer. Plutonium could fill this role, and has the advantages that there were six times as many atoms of Pu as of 137Cs in fallout, and any loss to decay has been negligible due to the long half-lives of the plutonium isotopes. Uranium-236 is another long-lived fallout isotope with significant potential for exploitation as a tracer of soil and sediment movement. Uranium is expected to be more mobile in soils than plutonium (or caesium), and hence the 236U/Pu ratio will vary with soil depth, and so could provide an independent measure of the amount of soil loss. In this paper we discuss accelerator based ultra-sensitive measurements of plutonium and 236U isotopes and their advantages over 137Cs as tracers of soil erosion and sediment movement.

  16. EXOTIC MAGNETS FOR ACCELERATORS.

    Energy Technology Data Exchange (ETDEWEB)

    WANDERER, P.

    2005-09-18

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

  17. Is Global Warming Accelerating?

    Science.gov (United States)

    Shukla, J.; Delsole, T. M.; Tippett, M. K.

    2009-12-01

    A global pattern that fluctuates naturally on decadal time scales is identified in climate simulations and observations. This newly discovered component, called the Global Multidecadal Oscillation (GMO), is related to the Atlantic Meridional Oscillation and shown to account for a substantial fraction of decadal fluctuations in the observed global average sea surface temperature. IPCC-class climate models generally underestimate the variance of the GMO, and hence underestimate the decadal fluctuations due to this component of natural variability. Decomposing observed sea surface temperature into a component due to anthropogenic and natural radiative forcing plus the GMO, reveals that most multidecadal fluctuations in the observed global average sea surface temperature can be accounted for by these two components alone. The fact that the GMO varies naturally on multidecadal time scales implies that it can be predicted with some skill on decadal time scales, which provides a scientific rationale for decadal predictions. Furthermore, the GMO is shown to account for about half of the warming in the last 25 years and hence a substantial fraction of the recent acceleration in the rate of increase in global average sea surface temperature. Nevertheless, in terms of the global average “well-observed” sea surface temperature, the GMO can account for only about 0.1° C in transient, decadal-scale fluctuations, not the century-long 1° C warming that has been observed during the twentieth century.

  18. Accelerating quantum universe

    CERN Document Server

    Kuzmichev, V E

    2007-01-01

    The exactly solvable quantum model of the homogeneous, isotropic and closed universe filled with a uniform scalar field and a perfect fluid which defines a reference frame is considered. The equations of the model are reduced to the form which allows a direct comparison between them and the equations of the Einstein classical theory of gravity. It is shown that matter in the universe has a component in a form of a condensate of massive zero-momentum excitation quanta of oscillations of a primordial scalar field which behaves as an antigravitating medium. The theory predicts an accelerating expansion of the universe even if the vacuum energy density vanishes. An antigravitating effect of a condensate has a purely quantum nature. It is ensured by quantum transitions between close states of the universe with different masses of a condensate. It is shown that in a state with large quantum numbers (in semi-classical approximation) the universe has to look effectively like spatially flat with a deceleration paramet...

  19. EXHIBITION: Accelerated Particles

    CERN Document Server

    2004-01-01

    An exhibition of plastic arts and two evenings of performances by sound and visual artists as part of CERN's 50th anniversary celebrations. Fifty candles for CERN, an international laboratory renowned for fundamental research, is a cause for celebration. Since March this year, Geneva and neighbouring parts of France have been the venues for a wealth of small and large-scale events, which will continue until November. Given CERN's location in the commune of Meyrin, the ForuMeyrin is hosting exhibitions of plastic arts and performances entitled: Accelerated Particles. Several works will be exhibited and performed in two 'salons'. Salon des matières: An exhibition of plastic arts From Tues 12 October to Wed 3 November 2004 Tuesdays to Fridays: 16:00 to 19:00 Saturdays: 14:00 to 18:00 Exhibition open late on performance nights, entrance free Salon des particules: Musical and visual performances Tues 12 and Mon 25 October from 20:00 to 23:00 Preview evening for both events: Tues 12 October from 18:...

  20. EXHIBITION: Accelerated Particles

    CERN Multimedia

    2004-01-01

    http://www.cern.ch/cern50/ An exhibition of plastic arts and two evenings of performances by sound and visual artists as part of CERN's fiftieth anniversary celebrations. The fiftieth anniversary of a world famous organization like CERN, an international laboratory specializing in fundamental research, is a cause for celebration. Since March this year, Geneva and neighbouring parts of France have been the venues for a wealth of small and large-scale events, which will continue until November. Given CERN's location in the commune of Meyrin, the ForuMeyrin is hosting two "salons" consisting of an exhibition of plastic arts and evenings of music and visual arts performances with the collective title of "Accelerated Particles". Several works will be exhibited and performed. Salon des matières: An exhibition of plastic arts Until Wednesday 3 November 2004. Tuesdays to Fridays: 4.00 p.m. to 7.00 p.m. Saturdays: 2.00 p.m. to 6.00 p.m. Doors open late on the evening of the performances. Salon des ...

  1. The entangled accelerating universe

    International Nuclear Information System (INIS)

    Using the known result that the nucleation of baby universes in correlated pairs is equivalent to spacetime squeezing, we show in this Letter that there exists a T-duality symmetry between two-dimensional warp drives, which are physically expressible as localized de Sitter little universes, and two-dimensional Tolman-Hawking and Gidding-Strominger baby universes respectively correlated in pairs, so that the creation of warp drives is also equivalent to spacetime squeezing. Perhaps more importantly, it has been also seen that the nucleation of warp drives entails a violation of the Bell's inequalities, and hence the phenomena of quantum entanglement, complementarity and wave function collapse. These results are generalized to the case of any dynamically accelerating universe filled with dark or phantom energy whose creation is also physically equivalent to spacetime squeezing and to the violation of the Bell's inequalities, so that the universe we are living in should be governed by essential sharp quantum theory laws and must be a quantum entangled system.

  2. LHC Dipoles Accelerate

    CERN Multimedia

    2001-01-01

    Andrezej Siemko (left), Peter Sievers (centre), and Lucio Rossi (right), have the exciting challenge of preparing and testing 2000 magnets for the LHC. The LHC is going to require a lot of powerful magnets by the time it begins operation in 2006. More specifically, it is going to need 130 special magnets, 400 quadrupoles, and a whopping 1250 dipoles! Preparing and testing these magnets for the conditions they will encounter in the LHC is not an easy task. But evaluation of the most recently received magnet, from the German company Noell, is showing that while the monumental task of receiving and testing nearly 2000 magnets is going to be exhausting, the goals are definitely attainable. At the moment and over the next year, pre-series magnets (the magnets that CERN uses to fine tune performance) are arriving slowly (90 in total will arrive), but by 2003 the rate of series magnet arrival will accelerate to 9 per week, that's over 450 in a single year! And working with these magnets when they arrive is tough. ...

  3. Pulsed Superconductivity Acceleration

    CERN Document Server

    Liepe, M

    2000-01-01

    The design of the proposed linear collider TESLA is based on 9-cell 1.3 GHz superconducting niobium cavities, operated in pulsed mode. Within the framework of an international collaboration the TESLA Test Facility (TTF) has been set up at DESY, providing the infrastructure for cavity R&D towards higher gradients. More than 60 nine-cell cavities were tested, accelerating gradients as high as 30 MV/m were measured. In the second production of TTF-cavities the average gradient was measured to be 24.7 MV/m. Two modules, each containing eight resonators, are presently used in the TTF-linac. These cavities are operated in pulsed mode: 0.8 ms constant gradient with up to 10 Hz repetitions rate. We will focus on two aspects: Firstly, the cavity fabrication and treatment is discussed, allowing to reach high gradients. Latest results of single cell cavities will be shown, going beyond 40 MV/m. Secondly, the pulsed mode operation of superconducting cavities is reviewed. This includes Lorentz force detuning, mechanic...

  4. SPS RF Accelerating Cavity

    CERN Multimedia

    1979-01-01

    This picture shows one of the 2 new cavities installed in 1978-1979. The main RF-system of the SPS comprises four cavities: two of 20 m length and two of 16.5 m length. They are all installed in one long straight section (LSS 3). These cavities are of the travelling-wave type operating at a centre frequency of 200.2 MHz. They are wideband, filling time about 700 ns and untuned. The power amplifiers, using tetrodes are installed in a surface building 200 m from the cavities. Initially only two cavities were installed, a third cavity was installed in 1978 and a forth one in 1979. The number of power amplifiers was also increased: to the first 2 MW plant a second 2 MW plant was added and by end 1979 there were 8 500 kW units combined in pairs to feed each of the 4 cavities with up to about 1 MW RF power, resulting in a total accelerating voltage of about 8 MV. See also 7412016X, 7412017X, 7411048X

  5. Actinides, accelerators and erosion

    Directory of Open Access Journals (Sweden)

    Fifield L.K.

    2012-10-01

    Full Text Available Fallout isotopes can be used as artificial tracers of soil erosion and sediment accumulation. The most commonly used isotope to date has been 137Cs. Concentrations of 137Cs are, however, significantly lower in the Southern Hemisphere, and furthermore have now declined to 35% of original values due to radioactive decay. As a consequence the future utility of 137Cs is limited in Australia, with many erosion applications becoming untenable within the next 20 years, and there is a need to replace it with another tracer. Plutonium could fill this role, and has the advantages that there were six times as many atoms of Pu as of 137Cs in fallout, and any loss to decay has been negligible due to the long half-lives of the plutonium isotopes. Uranium-236 is another long-lived fallout isotope with significant potential for exploitation as a tracer of soil and sediment movement. Uranium is expected to be more mobile in soils than plutonium (or caesium, and hence the 236U/Pu ratio will vary with soil depth, and so could provide an independent measure of the amount of soil loss. In this paper we discuss accelerator based ultra-sensitive measurements of plutonium and 236U isotopes and their advantages over 137Cs as tracers of soil erosion and sediment movement.

  6. Heavy ion accelerators at GSI

    International Nuclear Information System (INIS)

    The status of the Unilac heavy ion linear accelerator at GSI, Darmstadt is given. A schematic overall plan view of the Unilac is shown and its systems are described. List of isotopes and intensities accelerated at the Unilac is presented. The experimental possibilities at GSI should be considerably extended by a heavy ion synchrotron (SIS 18) in combination with an experimental storage ring (ESR). A prototype of the rf-accelerating system of the synchrotron has been built and tested. Prototypes for the quadrupole and dipole magnets for the ring are being constructed. The SIS 18 is desigmed for a maximum magnetic rigidity of 18Tm so that neon can be accelerated to 2 GeV/W and uranium to 1 GeV/u. The design allows also the acceleration of protons up to 4.5 GeV. The ESR permits to storage fully stripped uranium ions up to an energy of approximately R50 MeV/u

  7. Industrial accelerators and their applications

    CERN Document Server

    Hamm, Marianne E

    2012-01-01

    This unique new book is a comprehensive review of the many current industrial applications of particle accelerators, written by experts in each of these fields. Readers will gain a broad understanding of the principles of these applications, the extent to which they are employed, and the accelerator technology utilized. The book also serves as a thorough introduction to these fields for non-experts and laymen. Due to the increased interest in industrial applications, there is a growing interest among accelerator physicists and many other scientists worldwide in understanding how accelerators are used in various applications. The government agencies that fund scientific research with accelerators are also seeking more information on the many commercial applications that have been or can be developed with the technology developments they are funding. Many industries are also doing more research on how they can improve their products or processes using particle beams.

  8. Maximal acceleration and radiative processes

    CERN Document Server

    Papini, Giorgio

    2015-01-01

    We derive the radiation characteristics of an accelerated, charged particle in a model due to Caianiello in which the proper acceleration of a particle of mass $m$ has the upper limit $\\mathcal{A}_m=2mc^3/\\hbar$. We find two power laws, one applicable to lower accelerations, the other more suitable for accelerations closer to $\\mathcal{A}_m$ and to the related physical singularity in the Ricci scalar. Geometrical constraints and power spectra are also discussed. By comparing the power laws due to the maximal acceleration with that for particles in gravitational fields, we find that the model of Caianiello allows, in principle, the use of charged particles as tools to distinguish inertial from gravitational fields locally.

  9. Maximal acceleration and radiative processes

    Science.gov (United States)

    Papini, Giorgio

    2015-08-01

    We derive the radiation characteristics of an accelerated, charged particle in a model due to Caianiello in which the proper acceleration of a particle of mass m has the upper limit 𝒜m = 2mc3/ℏ. We find two power laws, one applicable to lower accelerations, the other more suitable for accelerations closer to 𝒜m and to the related physical singularity in the Ricci scalar. Geometrical constraints and power spectra are also discussed. By comparing the power laws due to the maximal acceleration (MA) with that for particles in gravitational fields, we find that the model of Caianiello allows, in principle, the use of charged particles as tools to distinguish inertial from gravitational fields locally.

  10. The ISAC post-accelerator

    Science.gov (United States)

    Laxdal, R. E.; Marchetto, M.

    2014-01-01

    The acceleration chain of the ISAC facility boosts the energy of both radioactive and stable light and heavy ions for beam delivery to both a medium energy area in ISAC-I and a high energy area in ISAC-II. The post-accelerator comprises a 35.4 MHz RFQ to accelerate beams of A/q ≤ 30 from 2 keV/u to 150 keV/u and a post stripper, 106.1 MHz variable energy drift tube linac (DTL) to accelerate ions of A/q ≤ 6 to a final energy between 0.15 MeV/u to 1.5 MeV/u. A 40 MV superconducting linac further accelerates beam from 1.5 MeV/u to energies above the Coulomb barrier. All linacs operate cw to preserve beam intensity.

  11. Particle Acceleration in Astrophysical Sources

    CERN Document Server

    Amato, Elena

    2015-01-01

    Astrophysical sources are extremely efficient accelerators. Some sources emit photons up to multi-TeV energies, a signature of the presence, within them, of particles with energies much higher than those achievable with the largest accelerators on Earth. Even more compelling evidence comes from the study of Cosmic Rays, charged relativistic particles that reach the Earth with incredibly high energies: at the highest energy end of their spectrum, these subatomic particles are carrying a macroscopic energy, up to a few Joules. Here I will address the best candidate sources and mechanisms as cosmic particle accelerators. I will mainly focus on Galactic sources such as Supernova Remnants and Pulsar Wind Nebulae, which being close and bright, are the best studied among astrophysical accelerators. These sources are held responsible for most of the energy that is put in relativistic particles in the Universe, but they are not thought to accelerate particles up to the highest individual energies, $\\approx 10^{20}$ eV...

  12. Ion sources for electrostatic accelerators

    International Nuclear Information System (INIS)

    Maybe the most important part of an electrostatic accelerator system, and also often the most tricky part is the ion source. There has been a rapid growth in activity in ion-source research and development during the last two to three decades. Some of these developments have also been of benefit to electrostatic accelerator users. In this report some of the different types of ion sources used in electrostatic accelerators are described. The list is not complete but more an overview of some of the more commonly used sources. The description is divided into two groups; positive ion sources for single stage electrostatic accelerators and negative ion sources for two stages (i.e. tandem) accelerators

  13. Velocity bunching in travelling wave accelerator with low acceleration gradient

    CERN Document Server

    Huang, Rui-Xuan; Li, Wei-Wei; Jia, Qi-Ka

    2013-01-01

    We present the analytical and simulated results concerning the influences of the acceleration gradient in the velocity bunching process, which is a bunch compression scheme that uses a traveling wave accelerating structure as a compressor. Our study shows that the bunch compression application with low acceleration gradient is more tolerant to phase jitter and more successful to obtain compressed electron beam with symmetrical longitudinal distribution and low energy spread. We also present a transverse emittance compensation scheme to compensate the emittance growth caused by the increasing of the space charge force in the compressing process that is easy to be adjusted for different compressing factors.

  14. Accelerated coffee pulp composting.

    Science.gov (United States)

    Sánchez, G; Olguín, E J; Mercado, G

    1999-02-01

    The effect of two abundant, easily available and very low-cost agro-industrial organic residues, i.e., filter cake from the sugar industry and poultry litter, on the composting stabilization time of coffee pulp and on the quality of the produced compost, was evaluated. Piles of one cubic meter were built and monitored within the facilities of a coffee processing plant in the Coatepec region of the State of Veracruz, Mexico. Manual aeration was carried out once a week. A longer thermophilic period (28 days) and a much lower C/N ratio (in the range of 6.9-9.1) were observed in the piles containing the amendments, as compared to the control pile containing only coffee pulp (14 days and a C/N ratio of 14.4, respectively). The maximum assimilation rate of the reducing sugars was 1.6 g kg-1 d-1 (from 7.5 to 5.3%) during the first two weeks when accelerators were present in the proportion of 20% filter cake plus 20% poultry litter, while they accumulated at a rate of 1.2 g kg-1 d-1 (from 7.4 to 9.13%) during the same period in the control pile. The best combination of amendments was 30% filter cake with 20% poultry litter, resulting in a final nitrogen content as high as 4.81%. The second best combination was 20% filter cake with 10% poultry litter, resulting in a compost which also contained a high level of total nitrogen (4.54%). It was concluded that the use of these two residues enhanced the composting process of coffee pulp, promoting a shorter stabilization period and yielding a higher quality of compost.

  15. Operation of the accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Pardo, R.C.; Batzka, B.; Billquist, P.J. [and others

    1995-08-01

    Fiscal Year 1994 was the first year of seven-day operation since ATLAS became a national user facility in 1985. ATLAS made the most of the opportunity this year by providing 5200 hours of beam on-target to the research program. A record number of 60 experiments were completed and the {open_quotes}facility reliability{close_quotes} remained near the 90% level. Seven-day operation was made possible with the addition to the staff of two operator positions providing single-operator coverage during the weekend period. The normally scheduled coverage was augmented by an on-call list of system experts who respond to emergencies with phone-in advice and return to the Laboratory when necessary. This staffing approach continues but we rearranged our staffing patterns so that we now have one cryogenics engineer working a shift pattern which includes 8-hour daily coverage during the weekend. ATLAS provided a beam mix to users consisting of 26 different isotopic species, 23% of which were for A>100 in FY 1994. Approximately 60% of the beam time was provided by the Positive Ion Injector, slightly less than the usage rate of FY 1993. Experiments using uranium or lead beams accounted for 16.4% of the total beam time. The ECR ion source and high-voltage platform functioned well throughout the year. A new technique for solid material production in the source was developed which uses a sputtering process wherein the sample of material placed near the plasma chamber wall is biased negatively. Plasma ions are accelerated into the sample and material is sputtered from the surface into the plasma. This technique is now used routinely for many elements. Runs of calcium, germanium, nickel, lead, tellurium, and uranium were carried out with this technique.

  16. Accelerating DSMC data extraction.

    Energy Technology Data Exchange (ETDEWEB)

    Gallis, Michail A.; Piekos, Edward Stanley

    2006-10-01

    In many direct simulation Monte Carlo (DSMC) simulations, the majority of computation time is consumed after the flowfield reaches a steady state. This situation occurs when the desired output quantities are small compared to the background fluctuations. For example, gas flows in many microelectromechanical systems (MEMS) have mean speeds more than two orders of magnitude smaller than the thermal speeds of the molecules themselves. The current solution to this problem is to collect sufficient samples to achieve the desired resolution. This can be an arduous process because the error is inversely proportional to the square root of the number of samples so we must, for example, quadruple the samples to cut the error in half. This work is intended to improve this situation by employing more advanced techniques, from fields other than solely statistics, for determining the output quantities. Our strategy centers on exploiting information neglected by current techniques, which collect moments in each cell without regard to one another, values in neighboring cells, nor their evolution in time. Unlike many previous acceleration techniques that modify the method itself, the techniques examined in this work strictly post-process so they may be applied to any DSMC code without affecting its fidelity or generality. Many potential methods are drawn from successful applications in a diverse range of areas, from ultrasound imaging to financial market analysis. The most promising methods exploit relationships between variables in space, which always exist in DSMC due to the absence of shocks. Disparate techniques were shown to produce similar error reductions, suggesting that the results shown in this report may be typical of what is possible using these methods. Sample count reduction factors of approximately three to five were found to be typical, although factors exceeding ten were shown on some variables under some techniques.

  17. "small ACCELERATORS" 24 May - 2 June 2005

    CERN Multimedia

    2005-01-01

    CERN Accelerator School and Kernfysisch Versneller Instituut (KVI) Groningen, the Netherlands announce a course on "Small Accelerators", Hotel Golden Tulip Drenthe, Zeegse, the Netherlands, 24 May - 2 June 2005. This specialised course is dedicated to the physics and the main applications of small accelerators. The course will review the different accelerator types as well as their specificities in terms of accelerator physics.

  18. Application of electron accelerator worldwide

    Energy Technology Data Exchange (ETDEWEB)

    Machi, Sueo [Japan Atomic Industrial Forum, Inc., Tokyo (Japan)

    2003-02-01

    Electron accelerator is an important radiation source for radiation technology, which covers broad fields such as industry, health care, food and environmental protection. There are about 1,000 electron accelerators for radiation processing worldwide. Electron accelerator has advantage over Co-60 irradiator in term of high dose rate and power, assurance of safety, and higher economic performance at larger volume of irradiation. Accelerator generating higher energy in the range of 10 MeV and high power electron beam is now commercially available. There is a trend to use high-energy electron accelerator replacing Co-60 in case of large through-put of medical products. Irradiated foods, in particular species, are on the commercial market in 35 countries. Electron accelerator is used efficiently and economically for production of new or modified polymeric materials through radiation-induced cross-linking, grafting and polymerization reaction. Another important application of electron beam is the curing of surface coatings in the manufacture of products. Electron accelerators of large capacity are used for cleaning exhaust gases in industrial scale. Economic feasibility studies of this electron beam process have shown that this technology is more cost effective than the conventional process. It should be noted that the conventional limestone process produce gypsum as a by-product, which cannot be used in some countries. By contrast, the by-product of the electron beam process is a valuable fertilizer. (Y. Tanaka)

  19. Application of electron accelerator worldwide

    International Nuclear Information System (INIS)

    Electron accelerator is an important radiation source for radiation technology, which covers broad fields such as industry, health care, food and environmental protection. There are about 1,000 electron accelerators for radiation processing worldwide. Electron accelerator has advantage over Co-60 irradiator in term of high dose rate and power, assurance of safety, and higher economic performance at larger volume of irradiation. Accelerator generating higher energy in the range of 10 MeV and high power electron beam is now commercially available. There is a trend to use high-energy electron accelerator replacing Co-60 in case of large through-put of medical products. Irradiated foods, in particular species, are on the commercial market in 35 countries. Electron accelerator is used efficiently and economically for production of new or modified polymeric materials through radiation-induced cross-linking, grafting and polymerization reaction. Another important application of electron beam is the curing of surface coatings in the manufacture of products. Electron accelerators of large capacity are used for cleaning exhaust gases in industrial scale. Economic feasibility studies of this electron beam process have shown that this technology is more cost effective than the conventional process. It should be noted that the conventional limestone process produce gypsum as a by-product, which cannot be used in some countries. By contrast, the by-product of the electron beam process is a valuable fertilizer. (Y. Tanaka)

  20. PROTON ACCELERATION AT OBLIQUE SHOCKS

    International Nuclear Information System (INIS)

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

  1. Proton Acceleration at Oblique Shocks

    Science.gov (United States)

    Galinsky, V. L.; Shevchenko, V. I.

    2011-06-01

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

  2. 2014 CERN Accelerator Schools: Beam Loss and Accelerator Protection

    CERN Multimedia

    2014-01-01

    The US-CERN-JAPAN-RUSSIA Joint International Accelerator School is organising a course on Beam Loss and Accelerator Protection to be held in Newport Beach, California, USA from 5-14 November, 2014.    This school is intended for physicists and engineers who are or may be engaged in the design, construction, and/or operation of accelerators with high power photon or particle beams and/or accelerator sub-systems with large stored energy. Application deadlines are 15 August and 4 September. Further information on this Joint School can be found at: http://cas.web.cern.ch/cas/JAS/Newport%20Beach%202014/NPBadvert.html http://indico.cern.ch/event/287647/ http://uspas.fnal.gov/programs/JAS/JAS14.shtml

  3. CAS CERN Accelerator School second advanced accelerator physics course

    International Nuclear Information System (INIS)

    The advanced course on general accelerator physics given in West Berlin closely followed that organised by the CERN Accelerator School at Oxford in September 1985 and whose proceedings were published as CERN Yellow Report 87-03 (1987). However, certain subjects were treated in a different way, improved or extended, while some new ones were introduced and it is all of these which are included in the present proceedings. The lectures include particle-photon interactions, high-brilliance lattices and single/multiple Touschek effect, while the seminars are on the major accelerators presently under construction or proposed for the near future, applications of synchrotron radiation, free-electron lasers, cosmic accelerators and crystal beams. Also included are errata, and addenda to some of the lectures, of CERN 87-03. (orig.)

  4. The Radiological Research Accelerator Facility

    International Nuclear Information System (INIS)

    The Radiological Research Accelerator Facility (RARAF) is based on a 4-MV Van de Graaff accelerator, which is used to generate a variety of well-characterized radiation beams for research in radiobiology, radiological physics, and radiation chemistry. It is part of the Center for Radiological Research (CRR) -- formerly the Radiological Research Laboratory (RRL) -- of Columbia University, and its operation is supported as a National Facility by the US Department of Energy (DOE). Fifteen different experiments were run during these 12 months, approximately the same as the previous two years. Brief summaries of each experiment are included. Accelerator usage is summarized and development activities are discussed. 7 refs., 4 tabs

  5. Stochastic modeling of Lagrangian accelerations

    Science.gov (United States)

    Reynolds, Andy

    2002-11-01

    It is shown how Sawford's second-order Lagrangian stochastic model (Phys. Fluids A 3, 1577-1586, 1991) for fluid-particle accelerations can be combined with a model for the evolution of the dissipation rate (Pope and Chen, Phys. Fluids A 2, 1437-1449, 1990) to produce a Lagrangian stochastic model that is consistent with both the measured distribution of Lagrangian accelerations (La Porta et al., Nature 409, 1017-1019, 2001) and Kolmogorov's similarity theory. The later condition is found not to be satisfied when a constant dissipation rate is employed and consistency with prescribed acceleration statistics is enforced through fulfilment of a well-mixed condition.

  6. Particle acceleration in modified shocks

    International Nuclear Information System (INIS)

    Efficient particle acceleration in shocks must modify the shock structure with consequent changes in the particle acceleration. This effect is studied and analytic solutions are found describing the diffusive acceleration of particles with momentum independent diffusion coefficients in hyperbolic tangent type velocity transitions. If the input particle spectrum is a delta function, the shock smoothing replaces the truncated power-law downstream particle spectrum by a more complicated form, but one which has a power-law tail at high momenta. For a cold plasma this solution can be made completely self-consistent. Some problems associated with momentum dependent diffusion coefficients are discussed. (author)

  7. Electromagnetic acceleration of permanent magnets

    CERN Document Server

    Dolya, S N

    2015-01-01

    We consider the acceleration of the permanent magnets, consisting of neodymium iron boron by means of the running magnetic field gradient. It is shown that the specific magnetic moment per nucleon in neodymium iron boron is determined by the remained magnetization of the substance. The maximum accessable gradient of the magnetic field accelerating the permanent magnets is determined by the coercive force thirty kilogauss. For the neodymium iron boron magnets this gradient is equal to twenty kilogauss divided by one centimeter. The finite velocity of the magnets six kilometers per second, the length of acceleration is six hundred thirty-seven meters.

  8. The wake field acceleration mechanism

    International Nuclear Information System (INIS)

    The wake fields of dense bunches of relativistic electrons are used to accelerate secondary beams of positrons and electrons. The basic principle is the transformation of wake forces by means of geometric structures with different impedances at different locations. In such wake field transformers beams of a few GeV energy can accelerate secondary beams to ten times the energy of the driving particles. Two 50 GeV colliding beam linear accelerators based on this mechanism occupy less than 1300 meters total length. (orig.)

  9. New type of collective accelerator

    International Nuclear Information System (INIS)

    A collective accelerator based on magnetically confined plasma rings is described. Typical rings which have been produced and which have 10 kJ magnetic energy and 0.1 to 10 coulombs of nuclei are predicted to be accelerated magnetically to 10 MJ or higher in acceleration lengths of 100 m if the final power delivered to the ring is 1012 W. Applications are discussed of current drive in Tokamak fusion reactions, fueling and heating magnetic fusion reactors, transuranic element synthesis, and, for focused rings, a high energy density driver for inertial confinement fusion

  10. Terahertz-driven linear electron acceleration

    CERN Document Server

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

    2014-01-01

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

  11. SNEAP 80: symposium of Northeastern Accelerator personnel

    International Nuclear Information System (INIS)

    Reports of operations are presented for twenty-seven facilities, along with reports on accelerators in progress, ion sources, insulating gases, charging systems, stripping foils, accelerating tubes, and upgraded accelerator systems

  12. SNEAP 80: symposium of Northeastern Accelerator personnel

    Energy Technology Data Exchange (ETDEWEB)

    Billen, J.H. (ed.)

    1980-01-01

    Reports of operations are presented for twenty-seven facilities, along with reports on accelerators in progress, ion sources, insulating gases, charging systems, stripping foils, accelerating tubes, and upgraded accelerator systems. (GHT)

  13. Accelerator technology working group summary

    International Nuclear Information System (INIS)

    A summary is presented of workshop deliberations on basic scaling, the economic viability of laser drive power for HEP accelerators, the availability of electron beam injectors for near-term experiments, and a few very general remarks on technology issues

  14. 1988 linear accelerator conference proceedings

    International Nuclear Information System (INIS)

    This report contains papers presented at the 1988 Linear Accelerator Conference. A few topics covered are beam dynamics; beam transport; superconducting components; free electron lasers; ion sources; and klystron research

  15. Accelerator and fusion research division

    International Nuclear Information System (INIS)

    This report contains brief discussions on research topics in the following area: Heavy-Ion Fusion Accelerator Research; Magnetic Fusion Energy; Advanced Light Source; Center for Beam Physics; Superconducting Magnets; and Bevalac Operations

  16. Accelerator structure work for NLC

    Energy Technology Data Exchange (ETDEWEB)

    Miller, R.H.; Adolphsen, C.; Bane, K.L.F.; Deruyter, H.; Farkas, Z.D.; Hoag, H.A.; Holtkamp, N.; Lavine, T.; Loew, G.A.; Nelson, E.M.; Palmer, R.B.; Paterson, J.M.; Ruth, R.D.; Thompson, K.A.; Vlieks, A.; Wang, J.W.; Wilson, P.B. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Gluckstern, R. [Maryland Univ., College Park, MD (United States); Ko, K.; Kroll, N. [Stanford Linear Accelerator Center, Menlo Park, CA (United States)]|[California Univ., San Diego, La Jolla, CA (United States). Dept. of Physics

    1992-07-01

    The NLC design achieves high luminosity with multiple bunches in each RF pulse. Acceleration of a train of bunches without emittance growth requires control of long range dipole wakefields. SLAC is pursuing a structure design which suppresses the effect of wakefields by varying the physical dimensions of successive cells of the disk-loaded traveling wave structure in a manner which spreads the frequencies of the higher mode while retaining the synchronism between the electrons and the accelerating mode. The wakefields of structures incorporating higher mode detuning have been measured at the Accelerator Test Facility at Argonne. Mechanical design and brazing techniques which avoid getting brazing alloy into the interior of the accelerator are being studied. A test facility for high-power testing of these structures is complete and high power testing has begun.

  17. Quantum aspects of accelerator optics

    OpenAIRE

    Khan, Sameen Ahmed

    1999-01-01

    Present understanding of accelerator optics is based mainly on classical mechanics and electrodynamics. In recent years quantum theory of charged-particle beam optics has been under development. In this paper the newly developed formalism is outlined.

  18. Electrodynamics acceleration of electrical dipoles

    CERN Document Server

    Dolya, S N

    2013-01-01

    This article considers the acceleration of electric dipoles consisting of thin metal plates and dielectric (barium titanate). The dipoles are of a cylindrical shape with a diameter of the cylinder two centimeters and length one centimeter. Capacity of the parallel-plate capacitor is three hundred picofarads and it is charged up to the voltage of two hundred eighty kilovolts. Pre-acceleration of the electric dipoles till velocity one kilometer per second is reached by the gas-dynamic method. The finite acceleration is produced in a spiral waveguide, where the pulse is travelling with voltage amplitude seven hundreds kilovolts and power one hundred twenty-five megawatts. This pulse travels via the spiral waveguide and accelerates the injected electric dipoles in the longitudinal direction till the finite velocity eight and a half kilometers per second over length seven hundred and seventy meters.

  19. drift tube for linear accelerator

    CERN Multimedia

    A drift tube from the Linac 1. This was the first tank of the linear accelerator Linac1, the injection system for the Proton Synchrotron, It ran for 34 years (1958 - 1992). Protons entered at the far end and were accelerated between the copper drift tubes by an oscillating electromagnetic field. The field flipped 200 million times a second (200 MHz) so the protons spent 5 nanoseconds crossing a drift tube and a gap. Moving down the tank, the tubes and gaps had to get longer as the protons gained speed. The tank accelerated protons from 500 KeV to 10 MeV. Linac1 was also used to accelerate deutrons and alpha particles for the Intersecting Storage Rings and oxygen and sulpher ions for the Super Proton Synchrotron heavy ion programme.

  20. Advanced Superconducting Test Accelerator (ASTA)

    Data.gov (United States)

    Federal Laboratory Consortium — The Advanced Superconducting Test Accelerator (ASTA) facility will be based on upgrades to the existing NML pulsed SRF facility. ASTA is envisioned to contain 3 to...

  1. Prototype of industrial electrons accelerator

    International Nuclear Information System (INIS)

    The interest and the necessity of Mexico's industry in the use of irradiation process has been increased in the last years. As examples are the irradiation of combustion gases (elimination of NOx and SO2) and the polymer cross-linking between others. At present time at least twelve enterprises require immediately of them which have been contacted by electron accelerators suppliers of foreign countries. The first project step consisted in to identify the electrons accelerator type that in can be constructed in Mexico with the major number of possible equipment, instruments, components and acquisition materials local and useful for the major number of users. the characteristics of the accelerator prototype are: accelerator type transformer with multiple secondary insulated and rectifier circuits with a potential of 0.8 MV of voltage, the second step it consisted in an economic study that permitted to demonstrate the economic feasibility of its construction. (Author)

  2. Accelerating advanced-materials commercialization

    Science.gov (United States)

    Maine, Elicia; Seegopaul, Purnesh

    2016-05-01

    Long commercialization times, high capital costs and sustained uncertainty deter investment in innovation for advanced materials. With appropriate strategies, technology and market uncertainties can be reduced, and the commercialization of advanced materials accelerated.

  3. Particle accelerator; the Universe machine

    CERN Multimedia

    Yurkewicz, Katie

    2008-01-01

    "In summer 2008, scientists will switch on one of the largest machines in the world to search for the smallest of particle. CERN's Large Hadron Collider particle accelerator has the potential to chagne our understanding of the Universe."

  4. IGBT accelerated aging data set.

    Data.gov (United States)

    National Aeronautics and Space Administration — Preliminary data from thermal overstress accelerated aging using the aging and characterization system. The data set contains aging data from 6 devices, one device...

  5. Accelerated Development of Organizational Talent

    OpenAIRE

    Korotov, Konstantin

    2007-01-01

    This working paper explores the challenges of accelerated development of organizational talent. The meaning of the word "accelerated" is that such development takes place at a pace that is significantly higher than that of "traditional" development that allows an individual to learn the intricacies of the current job, observe incumbents in a higher level position (usually, one level up), practice elements of the boss' job when being delegated tasks, undergoing formal training, or benefiting f...

  6. Electron Cloud Effects in Accelerators

    OpenAIRE

    Furman, M.A.

    2014-01-01

    Abstract We present a brief summary of various aspects of the electron-cloud effect (ECE) in accelerators. For further details, the reader is encouraged to refer to the proceedings of many prior workshops, either dedicated to EC or with significant EC contents, including the entire ?ECLOUD? series [1?22]. In addition, the proceedings of the various flavors of Particle Accelerator Conferences [23] contain a large number of EC-related publications. The ICFA Beam Dynamics...

  7. Caianiello's maximal acceleration. Recent developments

    OpenAIRE

    Papini, G.

    2004-01-01

    A quantum mechanical upper limit on the value of particle accelerations is consistent with the behavior of a class of superconductors and well known particle decay rates. It also sets limits on the mass of the Higgs boson and affects the stability of compact stars. In particular, type-I superconductors in static conditions offer an example of a dynamics in which acceleration has an upper limit.

  8. Sequentially pulsed traveling wave accelerator

    Science.gov (United States)

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

    2009-08-18

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

  9. Particle accelerators and scientific culture

    International Nuclear Information System (INIS)

    A historical review of fifty years of physics around particle accelerators, from the first nuclear reactions produced by beams of artificially accelerated particles to the large multinational projects now under discussion. The aim is to show how our description of natural phenomena has been shaped by advances in theoretical understanding, the development of new techniques, and the characters of men. Large use has been made of quotations from many of the scientists involved. (Auth.)

  10. Particle accelerators and scientific culture

    International Nuclear Information System (INIS)

    A historical review of fifty years of physics around particle accelerators, from the first nuclear reactions produced by beams of artificially accelerated particles to the large multinational projects now under discussion. The aim is to show how the description of natural phenomena has been shaped by advances in theoretical understanding, the development of new techniques, and the characters of men. Large use has been made of quotations from many of the scientists involved. (Auth.)

  11. The Beta Tech electron accelerator

    International Nuclear Information System (INIS)

    After describing the background of the Swedish Electron Sterilization Centre, the proposed linear accelerator sterilization plant is outlined. The accelerator will produce electrons of energy 10 MeV and a beam power of 30 KW. The handling system, control and identification systems are also described. Documentation will be designed around a bar code system on line to a computer. The various uses of dosimetry in plant performance and process control are described. (U.K.)

  12. Dark Energy or local acceleration?

    CERN Document Server

    Feoli, Antonio

    2016-01-01

    We find that an observer with a suitable acceleration relative to the frame comoving whit the cosmic fluid, in the context of the FRW decelerating universe, measures the same cosmological redshift as the LambdaCDM model. The estimated value of this acceleration is beta = 1.4x10^-9m/s^2. The problem of a too high peculiar velocity can be solved assuming, for the observer, a sort of helical motion.

  13. The acceleration of galactic cosmic rays

    International Nuclear Information System (INIS)

    A number of acceleration mechanisms are discussed including stochastic acceleration, shock acceleration, laminar shock acceleration and acceleration by shocks in scattering media. The self-consistent problem is analysed and it is concluded that provided the cosmic rays are scattered effectively and provided energy losses are not too severe, they can be very efficiently accelerated by shock waves in the interstellar medium. (C.F.)

  14. Test accelerator for linear collider

    International Nuclear Information System (INIS)

    KEK has proposed to build Test Accelerator Facility (TAF) capable of producing a 2.5 GeV electron beam for the purpose of stimulating R ampersand D for linear collider in TeV region. The TAF consists of a 1.5 GeV S-band linear accelerator, 1.5 GeV damping ring and 1.0 GeV X-band linear accelerator. The TAF project will be carried forward in three phases. Through Phase-I and Phase-II, the S-band and X-band linacs will be constructed, and in Phase-III, the damping ring will be completed. The construction of TAF Phase-I has started, and the 0.2 GeV S-band injector linac has been almost completed. The Phase-I linac is composed of a 240 keV electron gun, subharmonic bunchers, prebunchers and traveling buncher followed by high-gradient accelerating structures. The SLAC 5045 klystrons are driven at 450 kV in order to obtain the rf-power of 100 MW in a 1 μs pulse duration. The rf-power from a pair of klystrons are combined into an accelerating structure. The accelerating gradient up to 100 MeV/m will be obtained in a 0.6 m long structure. 5 refs., 3 figs., 2 tabs

  15. Ponderomotive Acceleration by Relativistic Waves

    CERN Document Server

    Lau, Calvin; Yeh, Po-Chun; Luk, Onnie; McClenaghan, Joseph; Ebisuzaki, Toshikazu; Tajima, Toshiki

    2014-01-01

    In the extreme high intensity regime of electromagnetic (EM) waves in plasma, the acceleration process is found to be dominated by the ponderomotive acceleration (PA). While the wakefields driven by the ponderomotive force of the relativistic intensity EM waves are important, they may be overtaken by the PA itself in the extreme high intensity regime when the dimensionless vector potential $a_0$ of the EM waves far exceeds unity. The energy gain by this regime (in 1D) is shown to be (approximately) proportional to $a_0^2$. Before reaching this extreme regime, the coexistence of the PA and the wakefield acceleration (WA) is observed where the wave structures driven by the wakefields show the phenomenon of multiple and folded wave-breakings. Investigated are various signatures of the acceleration processes such as the dependence on the mass ratio for the energy gain as well as the energy spectral features. The relevance to high energy cosmic ray acceleration and to the relativistic laser acceleration is conside...

  16. High-Intensity Proton Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Jay L. Hirshfield

    2011-12-27

    Analysis is presented for an eight-cavity proton cyclotron accelerator that could have advantages as compared with other accelerators because of its potentially high acceleration gradient. The high gradient is possible since protons orbit in a sequence of TE111 rotating mode cavities of equally diminishing frequencies with path lengths during acceleration that greatly exceed the cavity lengths. As the cavities operate at sequential harmonics of a basic repetition frequency, phase synchronism can be maintained over a relatively wide injection phase window without undue beam emittance growth. It is shown that use of radial vanes can allow cavity designs with significantly smaller radii, as compared with simple cylindrical cavities. Preliminary beam transport studies show that acceptable extraction and focusing of a proton beam after cyclic motion in this accelerator should be possible. Progress is also reported on design and tests of a four-cavity electron counterpart accelerator for experiments to study effects on beam quality arising from variations injection phase window width. This device is powered by four 500-MW pulsed amplifiers at 1500, 1800, 2100, and 2400 MHz that provide phase synchronous outputs, since they are driven from a with harmonics derived from a phase-locked 300 MHz source.

  17. Vacuum Brazing of Accelerator Components

    International Nuclear Information System (INIS)

    Commonly used materials for accelerator components are those which are vacuum compatible and thermally conductive. Stainless steel, aluminum and copper are common among them. Stainless steel is a poor heat conductor and not very common in use where good thermal conductivity is required. Aluminum and copper and their alloys meet the above requirements and are frequently used for the above purpose. The accelerator components made of aluminum and its alloys using welding process have become a common practice now a days. It is mandatory to use copper and its other grades in RF devices required for accelerators. Beam line and Front End components of the accelerators are fabricated from stainless steel and OFHC copper. Fabrication of components made of copper using welding process is very difficult and in most of the cases it is impossible. Fabrication and joining in such cases is possible using brazing process especially under vacuum and inert gas atmosphere. Several accelerator components have been vacuum brazed for Indus projects at Raja Ramanna Centre for Advanced Technology (RRCAT), Indore using vacuum brazing facility available at RRCAT, Indore. This paper presents details regarding development of the above mentioned high value and strategic components/assemblies. It will include basics required for vacuum brazing, details of vacuum brazing facility, joint design, fixturing of the jobs, selection of filler alloys, optimization of brazing parameters so as to obtain high quality brazed joints, brief description of vacuum brazed accelerator components etc.

  18. Accelerator and electrodynamics capability review

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Kevin W [Los Alamos National Laboratory

    2010-01-01

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

  19. Plasma Beat-Wave Acceleration

    Science.gov (United States)

    Clayton, Christopher E.

    2002-04-01

    Among all the advanced accelerator concepts that use lasers as the power source, most of the effort to date has been with the idea of using a laser pulse to excite a accelerating mode in a plasma. Within this area, there are a variety of approaches for creating the accelerating mode, as indicated by the other talks in this session. What is common to these approaches is the physics of how a laser pulse pushes on plasma electrons to organize electron-density perturbations, the sources of the ultra-high (> GeV/M) accelerating gradients. It is the "ponderomotive force", proportional to the local gradient of the of the laser intensity, that pushes plasma electrons forward (on the leading edge of the pulse) and backwards (on the trailing edge) which leads to harmonic motion of the electrons. As the laser pulse moves through the plasma at group velocity Vg c, the oscillating electrons show up macroscopically as a plasma mode or wave with frequency w equal to the plasma frequency and k = w/Vg. For short laser pulses, this is the Laser Wakefield Accelerator (LWFA) concept. Closely related is the Plasma Beat-Wave Acceleration (PBWA) concept. Here, the laser pulse that perturbs the plasma is composed of two closely-spaced frequencies that "beat", i.e., periodically constructively and destructively interfere, forming an electromagnetic beat wave. One can visualize this as a train of short pulses. If this beating frequency is set to the plasma frequency, then each pulse in the train will reinforce the density perturbation caused by the previous pulse. The principal advantage of multiple pulses driving up the plasma wave as opposed to a single pulse is in efficiency, allowing for the production of relatively large diameter (more 1-D like) accelerating modes. In this talk I will discuss past, current and planned PBWA experiments which are taking place at UCLA, RAL in England, and LULI in France.

  20. CAS Accelerator Physics (RF for Accelerators) in Denmark

    CERN Multimedia

    Barbara Strasser

    2010-01-01

    The CERN Accelerator School (CAS) and Aarhus University jointly organised a specialised course on RF for Accelerators, at the Ebeltoft Strand Hotel, Denmark from 8 to 17 June 2010.   Caption The challenging programme focused on the introduction of the underlying theory, the study and the performance of the different components involved in RF systems, the RF gymnastics and RF measurements and diagnostics. This academic part was supplemented with three afternoons dedicated to practical hands-on exercises. The school was very successful, with 100 participants representing 25 nationalities. Feedback from the participants was extremely positive, praising the expertise and enthusiasm of the lecturers, as well as the high standard and excellent quality of their lectures. In addition to the academic programme, the participants were able to visit a small industrial exhibition organised by Aarhus University and take part in a one-day excursion consisting of a visit of the accelerators operated ...

  1. The Accelerator Markup Language and the Universal Accelerator Parser

    Energy Technology Data Exchange (ETDEWEB)

    Sagan, D.; Forster, M.; /Cornell U., LNS; Bates, D.A.; /LBL, Berkeley; Wolski, A.; /Liverpool U. /Cockcroft Inst. Accel. Sci. Tech.; Schmidt, F.; /CERN; Walker, N.J.; /DESY; Larrieu, T.; Roblin, Y.; /Jefferson Lab; Pelaia, T.; /Oak Ridge; Tenenbaum, P.; Woodley, M.; /SLAC; Reiche, S.; /UCLA

    2006-10-06

    A major obstacle to collaboration on accelerator projects has been the sharing of lattice description files between modeling codes. To address this problem, a lattice description format called Accelerator Markup Language (AML) has been created. AML is based upon the standard eXtensible Markup Language (XML) format; this provides the flexibility for AML to be easily extended to satisfy changing requirements. In conjunction with AML, a software library, called the Universal Accelerator Parser (UAP), is being developed to speed the integration of AML into any program. The UAP is structured to make it relatively straightforward (by giving appropriate specifications) to read and write lattice files in any format. This will allow programs that use the UAP code to read a variety of different file formats. Additionally, this will greatly simplify conversion of files from one format to another. Currently, besides AML, the UAP supports the MAD lattice format.

  2. Accelerator mass spectrometry programme at BARC-TIFR pelletron accelerator

    International Nuclear Information System (INIS)

    Accelerator based mass spectrometry (ABMs) is an ultra sensitive means of counting individual atoms having sufficiently long half life and available in small amount. The 14 U D Pelletron Accelerator is an ideal machine to carry out ABMs studies with heavy isotopes like 36Cl and 129I. Cosmogenic radio isotope 36Cl is widely being detected using ABMs as it has got applications in ground water research, radioactive waste management, atmospheric 36Cl transport mechanism studies of Arctic Alpine ice core etc. As a part of the ongoing ABMs programme at 14UD Pelletron Accelerator Facility at Mumbai, a segmented gas detector developed for identification of 36Cl was tested for performance. Recently a beam chopper required for this measurement has been developed. Further progress made in this programme is discussed in this paper. (author)

  3. CAS CERN Accelerator School third general accelerator physics course

    International Nuclear Information System (INIS)

    The general course on accelerator physics given in Salamanca, Spain, closely followed those organised by the CERN Accelerator School at Gif-sur-Yvette, Paris in 1984, and at Aarhus, Denmark in 1986 and whose proceedings were published as CERN Yellow Reports 85-19 (1985) and 87-10 (1987) respectively. However, certain topics were treated in a different way, improved or extended, while some new ones were introduced and it is all of these which are included in the present proceedings. The lectures include beam-cooling concepts, Liouville's theorem and emittance, emittance dilution in transfer lines, weak-betatron coupling, diagnostics, while the seminars are on positron and electron sources, linac structures and the LEP L3 experiment, together with industrial aspects of particle accelerators. Also included are errata and addenda to the Yellow Reports mentioned above. (orig.)

  4. CAS CERN Accelerator School: Fourth general accelerator physics course

    International Nuclear Information System (INIS)

    The fourth CERN Accelerator School (CAS) basic course on General Accelerator Physics was given at KFA, Juelich, from 17 to 28 September 1990. Its syllabus was based on the previous similar courses held at Gif-sur-Yvette in 1984, Aarhus 1986, and Salamanca 1988, and whose proceedings were published as CERN Reports 85-19, 87-10, and 89-05, respectively. However, certain topics were treated in a different way, improved or extended, while new subjects were introduced. All of these appear in the present proceedings, which include lectures or seminars on the history and applications of accelerators, phase space and emittance, chromaticity, beam-beam effects, synchrotron radiation, radiation damping, tune measurement, transition, electron cooling, the designs of superconducting magnets, ring lattices, conventional RF cavities and ring RF systems, and an introduction to cyclotrons. (orig.)

  5. CAS CERN Accelerator School. Third advanced accelerator physics course

    International Nuclear Information System (INIS)

    The third version of the CERN Accelerator School's (CAS) advanced course on General Accelerator Physics was given at Uppsala University from 18-29 September, 1989. Its syllabus was based on the previous courses held in Oxford, 1985 and Berlin, 1987 whose proceedings were published as CERN Yellow Reports 87-03 and 89-01 respectively. However, the opportunity was taken to emphasize the physics of small accelerators and storage rings, to present some topics in new ways, and to introduce new seminars. Thus the lectures contained in the present volume include chromaticity, dynamic aperture, kinetic theory, Landau damping, ion-trapping, Schottky noise, laser cooling and small ring lattice problems while the seminars include interpretation of numerical tracking, internal targets and living with radiation. (orig.)

  6. Industrial Electron Accelerators Type ILU

    CERN Document Server

    Auslender, Vadim; Cheskidov, Vladimir; Faktorovich, Boris; Gorbunov, Vladimir; Gornakov, Igor; Nekhaev, V E; Panfilov, Alexander; Sidorov, Alexander; Tkachenko, Vadim; Tuvik, Alfred; Voronin, Leonid

    2005-01-01

    The report describes the electron accelerators of ILU series covering the energy range from 0.5 to 5 MeV with beam power up to 50 kW. The pulse linear accelerators type ILU are developed since 1970 in Budker institute of Nuclear Physics and are supplied to the industry. The ILU machines are purposed for wide application in various technological processes and designed for long continuous and round-the-clock work in industrial conditions. A principle of acceleration of electrons in the gap of HF resonator is used in the ILU machines. The HF resonator has toroidal form. The electron gun is placed in one of the protruding electrodes forming the accelerating gap of the resonator. The resonator is fed from HF autogenerator realized on the industrial triode, the feedback signal is given from the resonator. The absence of outer beam injection and usage of self-excited HF generator simplify the design of accelerator and ensure its reliable operation.

  7. A variable acceleration calibration system

    Science.gov (United States)

    Johnson, Thomas H.

    2011-12-01

    A variable acceleration calibration system that applies loads using gravitational and centripetal acceleration serves as an alternative, efficient and cost effective method for calibrating internal wind tunnel force balances. Two proof-of-concept variable acceleration calibration systems are designed, fabricated and tested. The NASA UT-36 force balance served as the test balance for the calibration experiments. The variable acceleration calibration systems are shown to be capable of performing three component calibration experiments with an approximate applied load error on the order of 1% of the full scale calibration loads. Sources of error are indentified using experimental design methods and a propagation of uncertainty analysis. Three types of uncertainty are indentified for the systems and are attributed to prediction error, calibration error and pure error. Angular velocity uncertainty is shown to be the largest indentified source of prediction error. The calibration uncertainties using a production variable acceleration based system are shown to be potentially equivalent to current methods. The production quality system can be realized using lighter materials and a more precise instrumentation. Further research is needed to account for balance deflection, forcing effects due to vibration, and large tare loads. A gyroscope measurement technique is shown to be capable of resolving the balance deflection angle calculation. Long term research objectives include a demonstration of a six degree of freedom calibration, and a large capacity balance calibration.

  8. Beam dynamics for induction accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Edward P., E-mail: eplee@lbl.gov

    2014-01-01

    An induction linac uses pulsed power that is applied directly, without any intervening resonant cavities, to accelerate a charged particle pulse. This approach can accommodate a large multiple-beam focusing lattice capable of transporting a large total beam current with a long pulse duration, which may be compressed while accelerating as well as afterward. The mean accelerating gradient is relatively low (less than about 1.5 MV/m), but the potential efficiency of energy transfer can be large up to about 50%. A multiple-beam induction linac is therefore a natural candidate accelerator for a heavy ion fusion (HIF) driver. However, the accelerated beams must meet stringent requirements on occupied phase space volume in order to be focused accurately and with small radius onto the fusion target. Dynamical considerations in the beam injector and linac, as well as in the final compression, final focus, and the fusion chamber, determine the quality of the driver beams as they approach the target. Requirements and tolerances derived from beam dynamics strongly influence the linac configuration and component design. After a summary of dynamical considerations, two major topics are addressed here: transportable current limits, which determine the choice of focal system for the linac, and longitudinal control of the beams, which are potentially destabilized by their interaction with the pulsed power system.

  9. Accelerator Technology Division annual report, FY 1989

    Energy Technology Data Exchange (ETDEWEB)

    1990-06-01

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

  10. 38 CFR 9.14 - Accelerated Benefits.

    Science.gov (United States)

    2010-07-01

    ...' GROUP LIFE INSURANCE AND VETERANS' GROUP LIFE INSURANCE § 9.14 Accelerated Benefits. (a) What is an Accelerated Benefit? An Accelerated Benefit is a payment of a portion of your Servicemembers' Group Life...? ____ Yes__ No__ The patient applied for an accelerated benefit under his/her government life...

  11. Accelerator Technology Division annual report, FY 1989

    International Nuclear Information System (INIS)

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

  12. Heavy ion toroidal collective accelerator

    International Nuclear Information System (INIS)

    Experiments on HIPAC at Maxwell Laboratories have shown that almost all of the confined electrons are trapped and do not go around the torus. A toroidal electric field produces a negligible toroidal electron current. An ion accelerator where electrons are magnetically contained and their space charge contains ions is considered. A toroidal electric field of suitable magnitude can be applied so that it accelerates all of the ions but does not accelerate most of the electrons. This is possible if the magnetic moment of electrons μsub(e) > μsub(i)/Z, where μsub(i) is the ion magnetic moment and Z is the charge of the ion. Ions would be contained by the electron space-charge electric field E, for energies up to ZeER/2 approximately 100 GeV where Z = 60, E = 107 V/cm and the major radius of the torus is R = 3.3 metres. (author)

  13. Superconducting magnet technology for accelerators

    International Nuclear Information System (INIS)

    A review article on superconducting magnets for accelerators should first answer the question, why superconductivity. The answer revolves around two pivotal facts: (1) fields in the range of 2 T to 10 T can be achieved; and (2) the operating cost can be less than conventional magnets. The relative importance of these two factors depends on the accelerator. In the case where an upgrade of an accelerator at an existing facility is planned, the ability to obtain fields higher than conventional magnets leads directly to an increase in machine energy for the given tunnel. In the case of a new facility, both factors must be balanced for the most economical machine. Ways to achieve this are discussed

  14. Virtual gap dielectric wall accelerator

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-11-05

    A virtual, moving accelerating gap is formed along an insulating tube in a dielectric wall accelerator (DWA) by locally controlling the conductivity of the tube. Localized voltage concentration is thus achieved by sequential activation of a variable resistive tube or stalk down the axis of an inductive voltage adder, producing a "virtual" traveling wave along the tube. The tube conductivity can be controlled at a desired location, which can be moved at a desired rate, by light illumination, or by photoconductive switches, or by other means. As a result, an impressed voltage along the tube appears predominantly over a local region, the virtual gap. By making the length of the tube large in comparison to the virtual gap length, the effective gain of the accelerator can be made very large.

  15. Relativistic shocks and particle acceleration

    International Nuclear Information System (INIS)

    In this paper, we investigate the fluid dynamics of relativistic shock waves, and use the results to calculate the spectral index of particles accelerated by the Fermi process in such shocks. We have calculated the distributions of Fermi-accelerated particles at shocks propagating into cold proton-electron plasma and also cold electron-positron plasma. We have considered two different power spectra for the scattering waves, and find, in contrast to the non-relativistic case, that the spectral index of the accelerated particles depends on the wave power spectrum. On the assumption of thermal equilibrium both upstream and downstream, we present some useful fits for the compression ratio of shocks propagating at arbitrary speeds into gas of any temperature. (author)

  16. Accelerator science in medical physics.

    Science.gov (United States)

    Peach, K; Wilson, P; Jones, B

    2011-12-01

    The use of cyclotrons and synchrotrons to accelerate charged particles in hospital settings for the purpose of cancer therapy is increasing. Consequently, there is a growing demand from medical physicists, radiographers, physicians and oncologists for articles that explain the basic physical concepts of these technologies. There are unique advantages and disadvantages to all methods of acceleration. Several promising alternative methods of accelerating particles also have to be considered since they will become increasingly available with time; however, there are still many technical problems with these that require solving. This article serves as an introduction to this complex area of physics, and will be of benefit to those engaged in cancer therapy, or who intend to acquire such technologies in the future. PMID:22374548

  17. Linear accelerator for radioisotope production

    Energy Technology Data Exchange (ETDEWEB)

    Hansborough, L.D.; Hamm, R.W.; Stovall, J.E.

    1982-02-01

    A 200- to 500-..mu..A source of 70- to 90-MeV protons would be a valuable asset to the nuclear medicine program. A linear accelerator (linac) can achieve this performance, and it can be extended to even higher energies and currents. Variable energy and current options are available. A 70-MeV linac is described, based on recent innovations in linear accelerator technology; it would be 27.3 m long and cost approx. $6 million. By operating the radio-frequency (rf) power system at a level necessary to produce a 500-..mu..A beam current, the cost of power deposited in the radioisotope-production target is comparable with existing cyclotrons. If the rf-power system is operated at full power, the same accelerator is capable of producing an 1140-..mu..A beam, and the cost per beam watt on the target is less than half that of comparable cyclotrons.

  18. Symposium on accelerator mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    None

    1981-01-01

    The area of accelerator mass spectrometry has expanded considerably over the past few years and established itself as an independent and interdisciplinary research field. Three years have passed since the first meeting was held at Rochester. A Symposium on Accelerator Mass Spectrometry was held at Argonne on May 11-13, 1981. In attendance were 96 scientists of whom 26 were from outside the United States. The present proceedings document the program and excitement of the field. Papers are arranged according to the original program. A few papers not presented at the meeting have been added to complete the information on the status of accelerator mass spectrometry. Individual papers were prepared separately for the data base.

  19. Symposium on accelerator mass spectrometry

    International Nuclear Information System (INIS)

    The area of accelerator mass spectrometry has expanded considerably over the past few years and established itself as an independent and interdisciplinary research field. Three years have passed since the first meeting was held at Rochester. A Symposium on Accelerator Mass Spectrometry was held at Argonne on May 11-13, 1981. In attendance were 96 scientists of whom 26 were from outside the United States. The present proceedings document the program and excitement of the field. Papers are arranged according to the original program. A few papers not presented at the meeting have been added to complete the information on the status of accelerator mass spectrometry. Individual papers were prepared separately for the data base

  20. Niobium LEP 2 accelerating cavities

    CERN Multimedia

    An accelerating cavity from LEP. This could be cut open to show the 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 were used in an upgrade of the LEP accelerator to double the energy of the particle beams.

  1. The Radiological Research Accelerator Facility

    International Nuclear Information System (INIS)

    The Radiological Research Accelerator Facility (RARAF) is based on 4-MV Van de Graaff accelerator, which is used to generate a variety of well-characterized radiation beams for research in radiobiology, radiological physics, and radiation chemistry. It is part of the Center for Radiological Research (CRR) -- formerly the Radiological Research Laboratory (RRL) -- of Columbia University, and its operation is supported as a National Facility by the US Department of Energy (DOE). As such, RARAF is available to all potential users on an equal basis, and scientists outside the CRR are encouraged to submit proposals for experiments at RARAF. The operation of the Van de Graaff is supported by the DOE, but the research projects themselves must be supported separately. Brief summaries of research experiments are included. Accelerator usage is summarized and development activities are discussed. 8 refs., 8 tabs

  2. Developments in laser-driven plasma accelerators

    CERN Document Server

    Hooker, Simon Martin

    2014-01-01

    Laser-driven plasma accelerators provide acceleration gradients three orders of magnitude greater than conventional machines, offering the potential to shrink the length of accelerators by the same factor. To date, laser-acceleration of electron beams to particle energies comparable to those offered by synchrotron light sources has been demonstrated with plasma acceleration stages only a few centimetres long. This article describes the principles of operation of laser-driven plasma accelerators, and reviews their development from their proposal in 1979 to recent demonstrations. The potential applications of plasma accelerators are described and the challenges which must be overcome before they can become a practical tool are discussed.

  3. The Diffusive Shock Acceleration Myth

    Science.gov (United States)

    Gloeckler, G.; Fisk, L. A.

    2012-12-01

    It is generally accepted that diffusive shock acceleration (DSA) is the dominant mechanism for particle acceleration at shocks. This is despite the overwhelming observational evidence that is contrary to predictions of DSA models. For example, our most recent survey of hourly-averaged, spin-averaged proton distribution functions around 61 locally observed shocks in 2001 at 1 AU found that in 21 cases no particles were accelerated. Spectral indices (γ ) of suprathermal tails on the velocity distributions around the 40 shocks that did accelerate particles, showed none of the DSA-predicted correlations of γ with the shock compression ratio and the shock normal to magnetic field angle. Here we will present ACE/SWICS observations of three sets of 72 consecutive one-hour averaged velocity distributions (in each of 8 SWICS spin sectors). Each set includes passage of one or more shocks or strong compression regions. All spectra were properly transformed to the solar wind frame using the detailed, updated SWICS forward model, taking into account the hourly-averaged directions of the solar wind flow, the magnetic field and the ACE spin axis (http://www.srl.caltech.edu/ACE/ASC/). The suprathermal tails are observed to be a combination of locally accelerated and remote tails. The local tails are power laws. The remote tails are also power laws with rollovers at higher energies. When local tails are weak (as is the case especially upstream of strong shocks or compression regions) the remote tails also have a rollover at low energies due to modulation (transport effects). Among our main findings are that (1) the spectral indices of both the local and remote tails are -5 within the uncertainties of the measurements, as predicted by our pump acceleration mechanism, and (2) the velocity distributions are anisotropic with the perpendicular (to the magnetic field) pressure greater than the parallel pressure.

  4. Harmonic ratcheting for fast acceleration

    Science.gov (United States)

    Cook, N.; Brennan, J. M.; Peggs, S.

    2014-04-01

    A major challenge in the design of rf cavities for the acceleration of medium-energy charged ions is the need to rapidly sweep the radio frequency over a large range. From low-power medical synchrotrons to high-power accelerator driven subcritical reactor systems, and from fixed focus alternating gradient accelerators to rapid cycling synchrotrons, there is a strong need for more efficient, and faster, acceleration of protons and light ions in the semirelativistic range of hundreds of MeV/u. A conventional way to achieve a large, rapid frequency sweep (perhaps over a range of a factor of 6) is to use custom-designed ferrite-loaded cavities. Ferrite rings enable the precise tuning of the resonant frequency of a cavity, through the control of the incremental permeability that is possible by introducing a pseudoconstant azimuthal magnetic field. However, rapid changes over large permeability ranges incur anomalous behavior such as the "Q-loss" and "f-dot" loss phenomena that limit performance while requiring high bias currents. Notwithstanding the incomplete understanding of these phenomena, they can be ameliorated by introducing a "harmonic ratcheting" acceleration scheme in which two or more rf cavities take turns accelerating the beam—one turns on when the other turns off, at different harmonics—so that the radio frequency can be constrained to remain in a smaller range. Harmonic ratcheting also has straightforward performance advantages, depending on the particular parameter set at hand. In some typical cases it is possible to halve the length of the cavities, or to double the effective gap voltage, or to double the repetition rate. This paper discusses and quantifies the advantages of harmonic ratcheting in general. Simulation results for the particular case of a rapid cycling medical synchrotron ratcheting from harmonic number 9 to 2 show that stability and performance criteria are met even when realistic engineering details are taken into consideration.

  5. Electron accelerators for radiation sterilization

    International Nuclear Information System (INIS)

    Industrial radiation processes using high power electron accelerators are attractive because the throughput rates are very high and the treatment costs per unit of product are often competitive with more conventional chemical processes. The utilization of energy in e-beam processing is more efficient than typical thermal processing. The use of volatiles or toxic chemicals can be avoided. Strict temperature or moisture controls may not be needed. Irradiated materials are usable immediately after processing. These capabilities are unique in that beneficial changes can be induced rapidly in solid materials and preformed products. In recent years, e-beam accelerators have emerged as the preferred alternative for industrial processing as they offer advantages over isotope radiation sources, such as (a) increased public acceptance since the storage, transport and disposal of radioactive material is not an issue; (b) the ability to hook up with the manufacturing process for in-line processing; (c) higher dose rates resulting in high throughputs. During the 1980s and 1990s, accelerator manufacturers dramatically increased the beam power available for high energy equipment. This effort was directed primarily at meeting the demands of the sterilization industry. During this era, the perception that bigger (higher power, higher energy) was always better prevailed, since the operating and capital costs of accelerators did not increase with power and energy as fast as the throughput. High power was needed to maintain low unit costs for the treatment. During the late 1980s and early 1990s, advances in e-beam technology produced new high energy, high power e-beam accelerators suitable for use in sterilization on an industrial scale. These newer designs achieved high levels of reliability and proved to be competitive with gamma sterilization by 60Co and fumigation with EtO. In parallel, technological advances towards 'miniaturization' of accelerators also made it possible to

  6. Plasma-based and novel accelerators

    International Nuclear Information System (INIS)

    This publication is a collection of papers presented at Workshop on Plasma-Based and Novel Accelerators held at National Institute for Fusion Science, Nagoya, on December 19-20, 1991. Plasma-based accelerators are attracting considerable attention in these days a new, exciting field of plasma applications. The study gives rise to and spurs study of other unique accelerators like laser-based accelerators. The talks in the Workshop encompassed beat-wave accelerator (BWA), plasma wake field accelerator (PWFA), Vp x B accelerator, laser-based accelerators and some novel methods of acceleration. They also covered the topics such as FEL, cluster acceleration and plasma lens. Small scale experiments as those in universities have exhibited brilliant results while larger scale experiments like BWA in Institute of Laser Engineering, Osaka University, and PWFA in KEK start showing significant results as well. (J.P.N.)

  7. State of accelerator for therapy

    CERN Document Server

    Maruhashi, A

    2002-01-01

    21 facilities carry out particle radiotherapy in the world and 6 facilities will start in the next year. They are shown in the table. 6 facilities of them exist in Japan. Small accelerator for proton therapy is developed. The area of them becomes smaller than 100 m sup 2. 5 makers, form, kinds of accelerator, length of track, beam energy of them are shown. States of particle radiotherapy in 4 facilities in Japan are explained by the kinds of particle, energy, beam intensity, time structure and radiation room. The important problems are reconsideration of building and compact rotating gantry. The problems of radiotherapy are explained. (S.Y.)

  8. Centralized digital control of accelerators

    International Nuclear Information System (INIS)

    In contrasting the title of this paper with a second paper to be presented at this conference entitled Distributed Digital Control of Accelerators, a potential reader might be led to believe that this paper will focus on systems whose computing intelligence is centered in one or more computers in a centralized location. Instead, this paper will describe the architectural evolution of SLAC's computer based accelerator control systems with respect to the distribution of their intelligence. However, the use of the word centralized in the title is appropriate because these systems are based on the use of centralized large and computationally powerful processors that are typically supported by networks of smaller distributed processors

  9. OpenMP for Accelerators

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-03-15

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

  10. Seismic response of linear accelerators

    OpenAIRE

    Collette, Christophe; Artoos, Kurt; Guinchard, Michael; Hauviller, Claude

    2010-01-01

    This paper is divided into two parts. The first part presents recent measurements of ground motion in the LHC tunnel at CERN. From these measurements, an update of the ground motion model currently used in accelerator simulations is presented. It contains new features like a model of the lateral motion and the technical noise. In the second part, it is shown how this model can be used to evaluate the seismic response of a linear accelerator in the frequency domain. Then, the approach is valid...

  11. Geometric integration for particle accelerators

    International Nuclear Information System (INIS)

    This paper is a very personal view of the field of geometric integration in accelerator physics-a field where often work of the highest quality is buried in lost technical notes or even not published; one has only to think of Simon van der Meer Nobel prize work on stochastic cooling-unpublished in any refereed journal. So I reconstructed the relevant history of geometrical integration in accelerator physics as much as I could by talking to collaborators and using my own understanding of the field. The reader should not be too surprised if this account is somewhere between history, science and perhaps even fiction

  12. Channel guiding for advanced accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Milchberg, H.M. [Institute for Physical Science and Technology (United States); Durfee, C.G. III [Institute for Physical Science and Technology (United States); Antonsen, T.M. [Institute for Plasma Research, University of Maryland, College Park, Maryland, (United States) 20742; Mora, P. [Centre de Physique Theorique, Ecole Polytechnique, 91128 Palaiseau (France)

    1996-02-01

    The recent demonstration of optical guiding of high intensity laser pulses in plasma waveguides [C. G. Durfee III and H. M. Milchberg, Phys. Rev. Lett 71, 2409 (1993)] has opened the way to new advances in the development of compact laser-driven electron particle accelerators. We review plasma waveguide properties relevant to intense pulse guiding and electron acceleration and show that the shock driven channels described here are well suited for stabilization of a large class of laser-plasma instabilities deleterious to high intensity guiding over long distances. {copyright} {ital 1996 American Institute of Physics.}

  13. Calorimetry at industrial electron accelerators

    DEFF Research Database (Denmark)

    Miller, Arne; Kovacs, A.

    1985-01-01

    Calorimetry is a convenient way to measure doses at industrial electron accelerators, where high absorbed doses (1-100 kGy) are delivered at dose rates of 102-105 Gy s-1 or even higher. Water calorimeters have been used for this purpose for several years, but recently other materials such as grap......Calorimetry is a convenient way to measure doses at industrial electron accelerators, where high absorbed doses (1-100 kGy) are delivered at dose rates of 102-105 Gy s-1 or even higher. Water calorimeters have been used for this purpose for several years, but recently other materials...

  14. Electron Cloud Effects in Accelerators

    CERN Document Server

    Furman, M A

    2013-01-01

    We present a brief summary of various aspects of the electron-cloud effect (ECE) in accelerators. For further details, the reader is encouraged to refer to the proceedings of many prior workshops, either dedicated to EC or with significant EC contents, including the entire "ECLOUD" series [122]. In addition, the proceedings of the various flavors of Particle Accelerator Conferences [23] contain a large number of EC-related publications. The ICFA Beam Dynamics Newsletter series [24] contains one dedicated issue, and several occasional articles, on EC. An extensive reference database is the LHC website on EC [25].

  15. Thermodynamics of Accelerating Black Holes

    CERN Document Server

    Appels, Michael; Kubiznak, David

    2016-01-01

    We address a long-standing problem of describing the thermodynamics of a charged accelerating black hole. We derive a standard first law of black hole thermodynamics, with the usual identification of entropy proportional to the area of the event horizon -- even though the event horizon contains a conical singularity. This result not only extends the applicability of black hole thermodynamics to realms previously not anticipated, it also opens a possibility for studying novel properties of an important class of exact radiative solutions of Einstein equations describing accelerated objects. We discuss the thermodynamic volume, stability and phase structure of these black holes.

  16. Electron Cloud Effects in Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Furman, M.A.

    2012-11-30

    Abstract We present a brief summary of various aspects of the electron-cloud effect (ECE) in accelerators. For further details, the reader is encouraged to refer to the proceedings of many prior workshops, either dedicated to EC or with significant EC contents, including the entire ?ECLOUD? series [1?22]. In addition, the proceedings of the various flavors of Particle Accelerator Conferences [23] contain a large number of EC-related publications. The ICFA Beam Dynamics Newsletter series [24] contains one dedicated issue, and several occasional articles, on EC. An extensive reference database is the LHC website on EC [25].

  17. Superconducting linear accelerator system for NSC

    Indian Academy of Sciences (India)

    P N Prakash; T S Datta; B P Ajith Kumar; J Antony; P Barua; J Chacko; A Choudhury; G K Chadhari; S Ghosh; S Kar; S A Krishnan; Manoj Kumar; Rajesh Kumar; A Mandal; D S Mathuria; R S Meena; R Mehta; K K Mistri; A Pandey; M V Suresh Babu; B K Sahu; A Sarkar; S S K Sonti; A Rai; S Venkatramanan; J Zacharias; R K Bhowmik; A Roy

    2002-11-01

    This paper reports the construction of a superconducting linear accelerator as a booster to the 15 UD Pelletron accelerator at Nuclear Science Centre, New Delhi. The LINAC will use superconducting niobium quarter wave resonators as the accelerating element. Construction of the linear accelerator has progressed sufficiently. Details of the entire accelerator system including the cryogenics facility, RF electronics development, facilities for fabricating niobium resonators indigenously, and present status of the project are presented.

  18. Essay: Accelerators, Beams And Physical Review Special Topics - Accelerators And Beams

    International Nuclear Information System (INIS)

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

  19. A portable accelerator control toolkit

    International Nuclear Information System (INIS)

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

  20. Geometrically focused neutral beam accelerators

    International Nuclear Information System (INIS)

    A more reliable 40 kV, 65 A power supply drain at 0.4 A/cm2, neutral-beam accelerator was developed for the Tandem Mirror Experiment (TMX). Multiple slotted aperture grids of 60% transparency are fabricated from refractory metal wires mounted to form a spherical surface. This geometrically focuses the beam by aiming individual beamlets at the center of curvature of the spherical grid (r = 3.2 m). We attain greater reliability and faster conditioning with geometrical focusing than with the previous technique of electrostatically steering beamlets to a common point. Electrostatic steering, accomplished by offsetting grid wires, is satisfactory if the offset of a beamlet is much less than the distance from the beamlet to the grids. It was found that Pierce Angle entrance grids performed better if sharper edged. A redesigned accelerator grid support structure reduced the number of ceramic-to-metal vacuum joints, and eliminated O rings between precisely aligned parts. The suppressor grid feedthrough is required to withstand a maximum voltage of 15 kV occurring during breakdown, greatly exceeding the operating voltage of 1.5 kV. Convenient fabrication and assembly techniques have been developed. Assembly of accelerators and plasma sources in a clean room appears to reduce the conditioning time. Following the successful testing of the prototype, eight 40 kV accelerators were built for TMX. Furthermore, ten 20 kV versions were built that are modifiable to 40 kV by exchanging the entrance grid

  1. Post-LHC accelerator magnets

    Energy Technology Data Exchange (ETDEWEB)

    Gourlay, Stephen A.

    2001-06-10

    The design and practicality of future accelerators, such as hadron colliders and neutrino factories being considered to supercede the LHC, will depend greatly on the choice of superconducting magnets. Various possibilities will be reviewed and discussed, taking into account recent progress and projected improvements in magnet design and conductor development along with the recommendations from the 2001 Snowmass workshop.

  2. Repair of overheating linear accelerator

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-01-01

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

  3. Petawatt pulsed-power accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Stygar, William A. (Albuquerque, NM); Cuneo, Michael E. (Albuquerque, NM); Headley, Daniel I. (Albuquerque, NM); Ives, Harry C. (Albuquerque, NM); Ives, legal representative; Berry Cottrell (Albuquerque, NM); Leeper, Ramon J. (Albuquerque, NM); Mazarakis, Michael G. (Albuquerque, NM); Olson, Craig L. (Albuquerque, NM); Porter, John L. (Sandia Park, NM); Wagoner; Tim C. (Albuquerque, NM)

    2010-03-16

    A petawatt pulsed-power accelerator can be driven by various types of electrical-pulse generators, including conventional Marx generators and linear-transformer drivers. The pulsed-power accelerator can be configured to drive an electrical load from one- or two-sides. Various types of loads can be driven; for example, the accelerator can be used to drive a high-current z-pinch load. When driven by slow-pulse generators (e.g., conventional Marx generators), the accelerator comprises an oil section comprising at least one pulse-generator level having a plurality of pulse generators; a water section comprising a pulse-forming circuit for each pulse generator and a level of monolithic triplate radial-transmission-line impedance transformers, that have variable impedance profiles, for each pulse-generator level; and a vacuum section comprising triplate magnetically insulated transmission lines that feed an electrical load. When driven by LTD generators or other fast-pulse generators, the need for the pulse-forming circuits in the water section can be eliminated.

  4. Calorimetry at industrial electron accelerators

    DEFF Research Database (Denmark)

    Miller, Arne; Kovacs, A.

    1985-01-01

    Calorimetry is a convenient way to measure doses at industrial electron accelerators, where high absorbed doses (1-100 kGy) are delivered at dose rates of 102-105 Gy s-1 or even higher. Water calorimeters have been used for this purpose for several years, but recently other materials such as...

  5. Advanced Accelerator Applications in Medicine

    International Nuclear Information System (INIS)

    besides the original purpose on development of particle acceleratora as research tools in nuclear and high-energy physics, there are large variety of accelerators used in various fileds from fundamental research to industrial usesand applications chemistry, biology and medicine. Pratical accelators used in various field of medical applications since serveral decades. Even through, a large fraction of applications is emphasized on cancer therappy, the number of accelerators used in midicine for other diagnostics and treatments has increased steady over the years. Several types of accelerated particles are used including electron, proton, neutron and ions. Presently, relativistic electron beams and radiation from linear accelerators (linas) are widely used. A combination of positron emission tomography (PRT) and radiotherapy is an example of excellent invention early detection and treat of cancer tumors. The most developments for proton and heavy ion therapy as well as a modern boron neutron capture therapy (BNCT) are also great incoming effective systems. This talk will focus on developments of the accelrator systems as well as overview on biophysical properties and medical aspects of the diacnostics and treatments.

  6. Accelerating cosmology in Rastall's theory

    CERN Document Server

    Capone, Monica; Ruggiero, Matteo Luca

    2009-01-01

    In an attempt to look for a viable mechanism leading to a present day accelerated expansion, we investigate the possibility that the observed cosmic speed up may be recovered in the framework of the Rastall's theory, relying on the non - conservativity of the stress - energy tensor, i.e. $T^{\\mu}_{\

  7. Physics Needs for Future Accelerators

    CERN Document Server

    Lykken, J D

    2000-01-01

    Contents: 1. Prologomena to any meta future physics 1.1 Physics needs for building future accelerators 1.2 Physics needs for funding future accelerators 2. Physics questions for future accelerators 2.1 Crimes and misapprehensions 2.1.1 Organized religion 2.1.2 Feudalism 2.1.3 Trotsky was right 2.2 The Standard Model as an effective field theory 2.3 What is the scale of new physics? 2.4 What could be out there? 2.5 Model-independent conclusions 3. Future accelerators 3.1 What is the physics driving the LHC? 3.2 What is the physics driving the LC? 3.2.1 Higgs physics is golden 3.2.2 LHC won't be sufficient to unravel the new physics as the TeV scale 3.2.3 LC precision measurements can pin down new physics scales 3.3 Why a Neutrino Factory? 3.4 Pushing the energy frontier

  8. Cosmological Acceleration from Gravitational Waves

    CERN Document Server

    Marochnik, Leonid

    2015-01-01

    It is shown that the classical gravitational waves of super-horizon wavelengths are able to form the de Sitter accelerated expansion of the empty (with no matter fields) Universe. The contemporary Universe is about 70% empty and asymptotically is going to become completely empty, so the effect caused by emptiness should be already very noticeable. It could manifest itself as the dark energy.

  9. ACCELERATION PHYSICS CODE WEB REPOSITORY.

    Energy Technology Data Exchange (ETDEWEB)

    WEI, J.

    2006-06-26

    In the framework of the CARE HHH European Network, we have developed a web-based dynamic accelerator-physics code repository. We describe the design, structure and contents of this repository, illustrate its usage, and discuss our future plans, with emphasis on code benchmarking.

  10. CERNois wins prestigious accelerator award

    CERN Multimedia

    Katarina Anthony

    2011-01-01

    During the 2nd International Particle Accelerator Conference, CERN’s Rogelio Tomás García became the first Spaniard to receive the Frank Sacherer Prize for his work in particle beam optics.   Rogelio Tomás García at the 2nd International Particle Accelerator Conference. The Frank Sacherer Prize is awarded to physicists who have made a “significant, original contribution to the accelerator field" early on in their career. This year the prize was given to Rogelio Tomás García who, at only 35 years of age, has made important contributions to the optics design, optics measurement, and correction techniques applied at both the LHC and Brookhaven’s RHIC. “Tomás has had a vital impact on CERN’s beam optics studies and has made very impressive achievements in the field of beam optics,” says Oliver Brüning, Head of the Accelerators and Beam Physics...

  11. Accelerator applications in energy and security

    CERN Document Server

    Chou, Weiren

    2015-01-01

    As accelerator science and technology progressed over the past several decades, the accelerators themselves have undergone major improvements in multiple performance factors: beam energy, beam power, and beam brightness. As a consequence, accelerators have found applications in a wide range of fields in our life and in our society. The current volume is dedicated to applications in energy and security, two of the most important and urgent topics in today's world. This volume makes an effort to provide a review as complete and up to date as possible of this broad and challenging subject. It contains overviews on each of the two topics and a series of articles for in-depth discussions including heavy ion accelerator driven inertial fusion, linear accelerator-based ADS systems, circular accelerator-based ADS systems, accelerator-reactor interface, accelerators for fusion material testing, cargo inspection, proton radiography, compact neutron generators and detectors. It also has a review article on accelerator ...

  12. CAS - CERN Accelerator School: Advanced Accelerator Physics Course

    CERN Document Server

    Herr, W

    2014-01-01

    This report presents the proceedings of the Course on Advanced Accelerator Physics organized by the CERN Accelerator School. The course was held in Trondheim, Norway from 18 to 29 August 2013, in collaboration with the Norwegian University of Science and Technology. Its syllabus was based on previous courses and in particular on the course held in Berlin 2003 whose proceedings were published as CERN Yellow Report CERN- 2006-002. The field has seen significant advances in recent years and some topics were presented in a new way and other topics were added. The lectures were supplemented with tutorials on key topics and 14 hours of hands on courses on Optics Design and Corrections, RF Measurement Techniques and Beam Instrumentation and Diagnostics. These courses are a key element of the Advanced Level Course.

  13. Traveling Wave Accelerating Structure for a Superconducting Accelerator

    CERN Document Server

    Kanareykin, Alex; Solyak, Nikolay

    2005-01-01

    We are presenting a superconducting traveling wave accelerating structure (STWA) concept, which may prove to be of crucial importance to the International Linear Collider. Compared to the existing design of a TESLA cavity, the traveling wave structure can provide ~20-40% higher accelerating gradient for the same aperture and the same peak surface magnetic RF field. The recently achieved SC structure gradient of 35 MV/m can be increased up to ~50 MV/m with the new STWA structure design. The STWA structure is supposed to be installed into the superconducting resonance ring and is fed by the two couplers with appropriate phase advance to excite a traveling wave inside the structure. The system requires two independent tuners to be able to adjust the cavity and feedback waveguide frequencies and hence to reduce the unwanted backward wave. In this presentation we discuss the structure design, optimization of the parameters, tuning requirements and plans for further development.

  14. CAS CERN Accelerator School: Power converters for particle accelerators

    International Nuclear Information System (INIS)

    This volume presents the proceedings of the fifth specialized course organized by the CERN Accelerator School, the subject on this occasion being power converters for particle accelerators. The course started with lectures on the classification and topologies of converters and on the guidelines for achieving high performance. It then went on to cover the more detailed aspects of feedback theory, simulation, measurements, components, remote control, fault diagnosis and equipment protection as well as systems and grid-related problems. The important topics of converter specification, procurement contract management and the likely future developments in semiconductor components were also covered. Although the course was principally directed towards DC and slow-pulsed supplies, lectures were added on fast converters and resonant excitation. Finally the programme was rounded off with three seminars on the related fields of Tokamak converters, battery energy storage for electric vehicles, and the control of shaft generators in ships. (orig.)

  15. CAS CERN Accelerator School: Superconductivity in particle accelerators. Proceedings

    International Nuclear Information System (INIS)

    These proceedings present the lectures given at the ninth specialized course organized by the CERN Accelerator School (CAS), the topic this time being ''Superconductivity in Particle Accelerators''. This course is basically a repeat of that given at the same location in 1988 whose proceedings were published as CERN 89-04. However, the opportunity was taken to improve the presentation of the various topics and to introduce the latest developments in this rapidly expanding field. First the basic theory of superconductivity is introduced. A review of the materials used for sc magnetics is followed by magnet design requirements, the influence of eddy and persistent currents, and the methods used to provide quench protection. Next follows the basic theory of sc cavities, their materials, high-gradient limitations, the problem of field emission and then their power couplers. After an introduction to cryogenics and cryoplants, the theory of superfluidity is presented followed by a review of the use of superfluid helium. Finally, two seminars detail the impact of superconductors in the design of the LHC and LEP2 accelerators. (orig.)

  16. Fresnel diffraction patterns as accelerating beams

    CERN Document Server

    Zhang, Yiqi; Zheng, Huaibin; Wu, Zhenkun; Li, Yuanyuan; Lu, Keqing; Zhang, Yanpeng

    2013-01-01

    We demonstrate that beams originating from Fresnel diffraction patterns are self-accelerating in free space. In addition to accelerating and self-healing, they also exhibit parabolic deceleration property, which is in stark contrast to other accelerating beams. We find that the trajectory of Fresnel paraxial accelerating beams is similar to that of nonparaxial Weber beams. Decelerating and accelerating regions are separated by a critical propagation distance, at which no acceleration is present. During deceleration, the Fresnel diffraction beams undergo self-smoothing, in which oscillations of the diffracted waves gradually focus and smooth out at the critical distance.

  17. Particle acceleration in space and laboratory plasmas

    International Nuclear Information System (INIS)

    The general principle of charged particle acceleration in space and laboratory plasmas is illustrated by a discussion of particular types of acceleration mechanisms which can be classified as either deterministic processes or stochastic processes. Acceleration by parallel electric fields, produced in double layers is an example of a deterministic process. Fermi acceleration and acceleration by turbulent wave fields are examples of stochastic processes. The physical acceleration mechanism involved in each type of process is discussed and examples given for space and laboratory plasmas. (author)

  18. Accelerate!

    Science.gov (United States)

    Kotter, John P

    2012-11-01

    The old ways of setting and implementing strategy are failing us, writes the author of Leading Change, in part because we can no longer keep up with the pace of change. Organizational leaders are torn between trying to stay ahead of increasingly fierce competition and needing to deliver this year's results. Although traditional hierarchies and managerial processes--the components of a company's "operating system"--can meet the daily demands of running an enterprise, they are rarely equipped to identify important hazards quickly, formulate creative strategic initiatives nimbly, and implement them speedily. The solution Kotter offers is a second system--an agile, networklike structure--that operates in concert with the first to create a dual operating system. In such a system the hierarchy can hand off the pursuit of big strategic initiatives to the strategy network, freeing itself to focus on incremental changes to improve efficiency. The network is populated by employees from all levels of the organization, giving it organizational knowledge, relationships, credibility, and influence. It can Liberate information from silos with ease. It has a dynamic structure free of bureaucratic layers, permitting a level of individualism, creativity, and innovation beyond the reach of any hierarchy. The network's core is a guiding coalition that represents each level and department in the hierarchy, with a broad range of skills. Its drivers are members of a "volunteer army" who are energized by and committed to the coalition's vividly formulated, high-stakes vision and strategy. Kotter has helped eight organizations, public and private, build dual operating systems over the past three years. He predicts that such systems will lead to long-term success in the 21st century--for shareholders, customers, employees, and companies themselves. PMID:23155997

  19. Accelerate!

    Science.gov (United States)

    Kotter, John P

    2012-11-01

    The old ways of setting and implementing strategy are failing us, writes the author of Leading Change, in part because we can no longer keep up with the pace of change. Organizational leaders are torn between trying to stay ahead of increasingly fierce competition and needing to deliver this year's results. Although traditional hierarchies and managerial processes--the components of a company's "operating system"--can meet the daily demands of running an enterprise, they are rarely equipped to identify important hazards quickly, formulate creative strategic initiatives nimbly, and implement them speedily. The solution Kotter offers is a second system--an agile, networklike structure--that operates in concert with the first to create a dual operating system. In such a system the hierarchy can hand off the pursuit of big strategic initiatives to the strategy network, freeing itself to focus on incremental changes to improve efficiency. The network is populated by employees from all levels of the organization, giving it organizational knowledge, relationships, credibility, and influence. It can Liberate information from silos with ease. It has a dynamic structure free of bureaucratic layers, permitting a level of individualism, creativity, and innovation beyond the reach of any hierarchy. The network's core is a guiding coalition that represents each level and department in the hierarchy, with a broad range of skills. Its drivers are members of a "volunteer army" who are energized by and committed to the coalition's vividly formulated, high-stakes vision and strategy. Kotter has helped eight organizations, public and private, build dual operating systems over the past three years. He predicts that such systems will lead to long-term success in the 21st century--for shareholders, customers, employees, and companies themselves.

  20. Accelerating structures pre-stripping section the milac heavy ion linear Accelerator MILAC

    International Nuclear Information System (INIS)

    Researches on development of new variants of accelerating structures for acceleration of the ions with A/q=20 in pre-stripping section PSS-20 are carried out. On an initial part of acceleration of ions from 6 up to 150 keV/u high capture in process of acceleration of the injected ions is provided interdigital (IH) accelerating structure with Radio-Frequency Quadrupole (RFQ) focusing. On the second part of acceleration of ions from 150 keV/u up to 1 MeV/u the highest rate of acceleration is created interdigital (IH) accelerating structure with drift tubes with the modified radio-frequency focusing.

  1. Elementary principles of linear accelerators

    International Nuclear Information System (INIS)

    These lectures come in five sections. The first is this introduction. The second is a short chronology of what are viewed as important milestones in the field. The third covers proton linacs. It introduces elementary concepts such as transit time, shunt impedance, and Q. Critical issues such as phase stability and transverse forces are discussed. The fourth section contains an elementary discussion of waveguide accelerating structures. It can be regarded as an introduction to some of the more advanced treatments of the subject. The final section is devoted to electron accelerators. Taking SLAC as an example, various topics are discussed such as structure design, choice of parameters, frequency optimization, beam current, emittance, bunch length and beam loading. Recent developments and future challenges are mentioned briefly. 41 figures, 4 tables

  2. Accelerator transmutation of 129I

    International Nuclear Information System (INIS)

    Iodine-129 is one of several long-lived reactor products that is being considered for transmutation by the Los Alamos Accelerator Transmutation of Waste (ATW) program. A reasonable rate of transmutation of 1291 is possible in this system because of the anticipated high neutron flux generated from the accelerator. This report summarizes previous papers dealing with the transmutation of 1291 where reactor technologies have been employed for neutron sources. The transmutation process is considered marginal under these conditions. Presented here are additional information concerning the final products that could be formed from the transmutation process in the ATW blanket. The transmutation scheme proposes the use of solid iodine as the target material and the escape of product xenon from the containers after van Dincklange (1981). Additional developmental plans are considered

  3. Greece welcomes CERN Accelerator School

    CERN Multimedia

    CAS School

    2011-01-01

    The CERN Accelerator School (CAS) and the University of the Aegean jointly organised a course on intermediate-level Accelerator Physics in Chios, Greece, from 19 to 30 September, 2011.   CAS Students pose for a group photo in Chios, Greece. This course followed the established format of the intermediate school, with lectures in the mornings and specialised courses in the afternoons. The latter provided “hands-on” education and experience in three topics: “RF Measurement Techniques”, “Beam Instrumentation and Diagnostics” and “Optics Design and Correction”.  Participants selected one of the three courses and followed the chosen topic throughout the school. Guided studies and tutorials on core subjects, seminars and a poster session completed the programme. An excursion included a visit to the Nea Moni monastery, a guided tour of two medieval villages, Pyrgi and Mesta, and finished with a typical Greek me...

  4. Neutrons from medical electron accelerators

    International Nuclear Information System (INIS)

    The significant sources of photoneutrons within a linear-accelerator treatment head are identified and absolute estimates of neutron production per treatment dose are given for typical components. Measured data obtained at a variety of accelerator installations are presented and compared with these calculations. It is found that the high-Z materials within the treatment head do not significantly alter the neutron fluence, but do substantially reduce the average energy of the transmitted spectrum. Reflected neutrons from the concrete treatment room contribute to the neutron fluence, but not substantially to the patient integral dose, because of a further reduction in average energy. Absolute depth-dose distributions for realistic neutron spectra are calculated, and a rapid falloff with depth is found

  5. Industrial Applications of Accelerator Technologies

    International Nuclear Information System (INIS)

    PEFP(Proton Engineering Frontier Project) put its aim on development of high power linear proton accelerator and its beam applications. So, it has, since late 1990's, accumulated accelerator and ion source technologies, supplied beam utilization service to related industry. As of now, right after 10 year long project(PEFP), many of its low energy beam technologies seem to be successfully utilized for industrial purpose to meet the market needs, especially in improvement of production process and manufacturing performance, new substance development, etc. In this context, it is high time to carry out in-depth industrialization development on PEFP's retained ion beam technology prowess: To help them diffused profitable markets as soon as possible. So, in this work, through verification on the industrialization feasibility by experiments, it is going to get it started, with cooperation of participatory company, to enter into markets with developed technology and products

  6. Industrial applications of electron accelerators

    CERN Document Server

    Cleland, M R

    2006-01-01

    This paper addresses the industrial applications of electron accelerators for modifying the physical, chemical or biological properties of materials and commercial products by treatment with ionizing radiation. Many beneficial effects can be obtained with these methods, which are known as radiation processing. The earliest practical applications occurred during the 1950s, and the business of radiation processing has been expanding since that time. The most prevalent applications are the modification of many different plastic and rubber products and the sterilization of single-use medical devices. Emerging applications are the pasteurization and preservation of foods and the treatment of toxic industrial wastes. Industrial accelerators can now provide electron energies greater than 10 MeV and average beam powers as high as 700 kW. The availability of high-energy, high-power electron beams is stimulating interest in the use of X-rays (bremsstrahlung) as an alternative to gamma rays from radioactive nuclides.

  7. CASE in CERN's accelerator sector

    International Nuclear Information System (INIS)

    As in the software industry where computer aided software engineering (CASE) methodologies and tools are commonly used, CERN endeavours to introduce this technology to improve the efficiency of designing, producing and maintaining software. A large project is currently under development in the administrative area whereas a dedicated group had been set up to evaluate state of the art techniques for software development relating to physics experiments. A similar activity, though on a smaller scale, has been initiated in the accelerator sector also in view of the large amount of software that will be required by the LEP200 and the LHC projects. This paper briefly describes this technology and gives an account of current experience with the use of CASE methods and tools for technical projects in the accelerator sector at CERN. (author)

  8. Hardware-Accelerated Simulated Radiography

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-08-04

    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 solutions to the radiative transport equation for X-rays. The hardware accelerated solutions are accurate enough to enable scientists to explore the experimental design space with greater efficiency than the methods currently in use. An unsorted hexahedron projection algorithm is presented for curvilinear hexahedral meshes 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.

  9. Self accelerating electron Airy beams

    CERN Document Server

    Voloch-Bloch, Noa; Lilach, Yigal; Gover, Avraham; Arie, Ady

    2013-01-01

    We report the first experimental generation and observation of Airy beams of free electrons. The electron Airy beams are generated by diffraction of electrons through a nanoscale hologram, that imprints a cubic phase modulation on the beams' transverse plane. We observed the spatial evolution dynamics of an arc-shaped, self accelerating and shape preserving electron Airy beams. We directly observed the ability of electrons to self-heal, restoring their original shape after passing an obstacle. This electromagnetic method opens up new avenues for steering electrons, like their photonic counterparts, since their wave packets can be imprinted with arbitrary shapes or trajectories. Furthermore, these beams can be easily manipulated using magnetic or electric potentials. It is also possible to efficiently self mix narrow beams having opposite signs of acceleration, hence obtaining a new type of electron interferometer.

  10. The US Muon Accelerator Program

    Energy Technology Data Exchange (ETDEWEB)

    Torun, Y.; /IIT, Chicago; Kirk, H.; /Brookhaven; Bross, A.; Geer, Steve; Shiltsev, Vladimir; /Fermilab; Zisman, M.; /LBL, Berkeley

    2010-05-01

    An accelerator complex that can produce ultra-intense beams of muons presents many opportunities to explore new physics. A facility of this type is unique in that, in a relatively straightforward way, it can present a physics program that can be staged and thus move forward incrementally, addressing exciting new physics at each step. At the request of the US Department of Energy's Office of High Energy Physics, the Neutrino Factory and Muon Collider Collaboration (NFMCC) and the Fermilab Muon Collider Task Force (MCTF) have recently submitted a proposal to create a Muon Accelerator Program that will have, as a primary goal, to deliver a Design Feasibility Study for an energy-frontier Muon Collider by the end of a 7 year R&D program. This paper presents a description of a Muon Collider facility and gives an overview of the proposal.

  11. Linear induction accelerator parameter options

    International Nuclear Information System (INIS)

    The principal undertaking of the Beam Research Program over the past decade has been the investigation of propagating intense self-focused beams. Recently, the major activity of the program has shifted toward the investigation of converting high quality electron beams directly to laser radiation. During the early years of the program, accelerator development was directed toward the generation of very high current (>10 kA), high energy beams (>50 MeV). In its new mission, the program has shifted the emphasis toward the production of lower current beams (>3 kA) with high brightness (>106 A/(rad-cm)2) at very high average power levels. In efforts to produce these intense beams, the state of the art of linear induction accelerators (LIA) has been advanced to the point of satisfying not only the current requirements but also future national needs

  12. Observational Probes of Cosmic Acceleration

    CERN Document Server

    Weinberg, David H; Eisenstein, Daniel J; Hirata, Christopher; Riess, Adam G; Rozo, Eduardo

    2012-01-01

    The accelerating expansion of the universe is the most surprising cosmological discovery in many decades, implying that the universe is dominated by some form of "dark energy" with exotic physical properties, or that Einstein's theory of gravity breaks down on cosmological scales. The profound implications of cosmic acceleration have inspired ambitious experimental efforts to measure the history of expansion and growth of structure with percent-level precision or higher. We review in detail the four most well established methods for making such measurements: Type Ia supernovae, baryon acoustic oscillations (BAO), weak gravitational lensing, and galaxy clusters. We pay particular attention to the systematic uncertainties in these techniques and to strategies for controlling them at the level needed to exploit "Stage IV" dark energy facilities such as BigBOSS, LSST, Euclid, and WFIRST. We briefly review a number of other approaches including redshift-space distortions, the Alcock-Paczynski test, and direct meas...

  13. Conformal Transformations and Accelerated Cosmologies

    OpenAIRE

    Crooks, James L.; Frampton, Paul H.

    2006-01-01

    A cosmological theory that predicts a late-time accelerated attractor with a constant dark matter to dark energy ratio can be said to solve the Coincidence Problem. Such cosmologies are naturally generated in the context of non-standard gravity theories under conformal transformation because of the resulting couplings between scalar fields and matter. The present work examines four classes of these transformed theories and finds that only a small subset--those with a single scalar field--are ...

  14. An Accelerated Incremental Radiosity Algorithm

    Institute of Scientific and Technical Information of China (English)

    XING Changyu; SUN Jizhou; R. L. Grimsdale

    2000-01-01

    The incremental radiosity method has been shown to be an efficient technique for providing global illumination in dynamic environments as it exploits temporal coherence in object space. This paper presents an accelerated incremental radiosity algorithm, which is based on a dynamically followed partial matrix.This not only reduces the computation cost in determining incremental form-factors when the geometrical relationships between objects are constantly changing, but also simplifies the management of user interaction with comparatively little storage cost.

  15. Status of JAERI tandem accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Tadashi; Kanda, Susumu; Takeuchi, Suehiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] (and others)

    2001-02-01

    JAERI Tandem Accelerator had been operated approximately 230 days in fiscal year of 1999. Meanwhile, we had three times of maintenance period with vent. Total operation-times were 5273 hours. We could not carry out the experiment using rare gas, due to malfunction of the RF power supply for the ECR ion source. The type of the RF power supply is peculiar and it is impossible to get spare parts for repair. We are now investigating the backup RF power supply. The power supply for the magnet became unstable due to degradation of insulation in the shunt resistance, which is used for feedback stabilization. Stability was recovered after cleaning. The acrylic resin shaft was cracked. This cracks have a potential for severe accidents. So far bearing of the shaft has no problem. The reason of cracks may be self-destruction by charge accumulation in the shaft. JAERI Tandem Accelerator is approximately 20 years old. There appear requirements on the higher ion currents for additional ion species. Therefore, authors are investigating cost effective improvement plans of RFQ (Radio Frequency Quadra-pole) and IH type accelerator based on KEK (High Energy Accelerator Research Organization) R and D. As a whole, maintenance services for the control system are increasing due to some changes of computer programs. There are some difficulties to keep skilled personnel for facilities operation. Authors are gradually increasing hired personnel with contract from 1993. However, loads for JAERI permanent staffs are still heavy. It takes much longer time to educate skilled persons especially for safety. (Y. Tanaka)

  16. An accelerator worth fighting for

    CERN Multimedia

    1996-01-01

    Financial pressures from member states have upset the calculations of the European Laboratory for Particle Physics's (CERN) major accelerator, the Large Hadron Collider (LHC). Despite preference for domestic high energy programs, CERN members accord high priority to LHC physics. Converting to a global facility can help spread the high annual cost of subscription. But given the political realities, a revision of the LHC project appears more feasible. CERN's management needs to deploy its skills to overcome the financial obstacles to the facility.

  17. Magnetosphere of an Accelerated Pulsar

    CERN Document Server

    Brennan, T Daniel

    2013-01-01

    We report on a remarkable class of exact solutions to force-free electrodynamics that has four-current along the light cones of an arbitrary timelike worldline in flat spacetime. No symmetry is assumed, and the solutions are given in terms of a free function of three variables. The field configuration should describe the outer magnetosphere of a pulsar moving on the worldline. The power radiated is the sum of an acceleration (Larmor-type) term and a pulsar-type term.

  18. Symplectic maps for accelerator lattices

    Energy Technology Data Exchange (ETDEWEB)

    Warnock, R.L.; Ruth, R.; Gabella, W.

    1988-05-01

    We describe a method for numerical construction of a symplectic map for particle propagation in a general accelerator lattice. The generating function of the map is obtained by integrating the Hamilton-Jacobi equation as an initial-value problem on a finite time interval. Given the generating function, the map is put in explicit form by means of a Fourier inversion technique. We give an example which suggests that the method has promise. 9 refs., 9 figs.

  19. Accelerator x-ray sources

    CERN Document Server

    Talman, Richard

    2007-01-01

    This first book to cover in-depth the generation of x-rays in particle accelerators focuses on electron beams produced by means of the novel Energy Recovery Linac (ERL) technology. The resulting highly brilliant x-rays are at the centre of this monograph, which continues where other books on the market stop. Written primarily for general, high energy and radiation physicists, the systematic treatment adopted by the work makes it equally suitable as an advanced textbook for young researchers.

  20. Geometry for the accelerating universe

    CERN Document Server

    Punzi, R; Wohlfarth, M N R; Punzi, Raffaele; Schuller, Frederic P.; Wohlfarth, Mattias N.R.

    2006-01-01

    The Lorentzian spacetime metric is replaced by an area metric which naturally emerges as a generalized geometry in quantum string and gauge theory. Employing the area metric curvature scalar, the gravitational Einstein-Hilbert action is re-interpreted as dynamics for an area metric. Without the need for dark energy or fine-tuning, area metric cosmology explains the observed small acceleration of the late Universe.

  1. Wave Detection in Acceleration Plethysmogram

    OpenAIRE

    Ahn, Jae Mok

    2015-01-01

    Objectives Acceleration plethysmogram (APG) obtained from the second derivative of photoplethysmography (PPG) is used to predict risk factors for atherosclerosis with age. This technique is promising for early screening of atherosclerotic pathologies. However, extraction of the wave indices of APG signals measured from the fingertip is challenging. In this paper, the development of a wave detection algorithm including a preamplifier based on a microcontroller that can detect the a, b, c, and ...

  2. Accelerating Around an Unbanked Curve

    Science.gov (United States)

    Mungan, Carl E.

    2006-02-01

    The December 2004 issue of TPT presented a problem concerning how a car should accelerate around an unbanked curve of constant radius r starting from rest if it is to avoid skidding. Interestingly enough, two solutions were proffered by readers.2 The purpose of this note is to compare and contrast the two approaches. Further experimental investigation of various turning strategies using a remote-controlled car and overhead video analysis could make for an interesting student project.

  3. Low voltage electron beam accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Ochi, Masafumi [Iwasaki Electric Co., Ltd., Tokyo (Japan)

    2003-02-01

    Widely used electron accelerators in industries are the electron beams with acceleration voltage at 300 kV or less. The typical examples are shown on manufactures in Japan, equipment configuration, operation, determination of process parameters, and basic maintenance requirement of the electron beam processors. New electron beam processors with acceleration voltage around 100 kV were introduced maintaining the relatively high dose speed capability of around 10,000 kGy x mpm at production by ESI (Energy Science Inc. USA, Iwasaki Electric Group). The application field like printing and coating for packaging requires treating thickness of 30 micron or less. It does not require high voltage over 110 kV. Also recently developed is a miniature bulb type electron beam tube with energy less than 60 kV. The new application area for this new electron beam tube is being searched. The drive force of this technology to spread in the industries would be further development of new application, process and market as well as the price reduction of the equipment, upon which further acknowledgement and acceptance of the technology to societies and industries would entirely depend. (Y. Tanaka)

  4. Injector Design for Advanced Accelerators

    Science.gov (United States)

    Henestroza, Enrique; Faltens, A.

    1996-11-01

    Accelerator designs intended to provide acceleration at a much lower cost per Joule than the ILSE or ELISE designs are under study. For these designs, which typically have many beams, an injector of significantly lower cost is needed. A goal, which from our design appears to be achievable, is to reduce the transverse dimension to half that of the 2 MeV, 800 mA ILSE injector(E. Henestroza, ``Injectors for Heavy Ion Fusion", Proc. of the 11th International Wkshp. on Laser Interaction and Related Plasma Phenomena, 1993.) while generating about the same current. A single channel of a lower cost injector includes an 800 kV column, accelerating a 700 mA beam extracted from a potassium source of 4 cm radius by a 120 kV electrode. The beam passes into a superconducting 7 T solenoid of 15 cm aperture and 15 cm length. This high-field solenoid provides the focusing needed for a small beam without increasing the electric field gradient. The injector and its matching section, also designed, fit within a 12 cm radius, which is small enough to allow construction of attractive multi-beam injectors. We will present solutions for the generation and transport of 700 mA potassium beams of up to 1.6 MeV within the same transverse constraint.

  5. Time derivative of earthquake acceleration

    Institute of Scientific and Technical Information of China (English)

    Mai Tong; Guo-Quan Wang; George C.Lee

    2005-01-01

    Unlike acceleration, velocity, and displacement, the time derivative of acceleration (TDoA) of ground motion has not been extensively studied. In this paper, the basic characteristics of TDoA are evaluated based on records from the 1999Chi-Chi, earthquake (Mw 7.6) and one of its aftershocks (Mw 6.2). It is found that the maximum TDoA at a free-field station was over 31,200 crm/s3 (31.8 g/s); and the duration of "strong" TDoA, between the first and the last time points exceeding 2,000 cm/s3 (2 g/s), was almost one minute near the epicenter area. Since ground TDoA sensors are not commonly available,the time series are calculated by direct numerical differentiation of acceleration time series. Relative error analysis shows that the error is non-transitive and total error is within 4%. The density function of TDoA amplitude, frequency content and spatial distribution of peak ground jerk (PGJ) are evaluated. The study also includes examination of some TDoA responses from a seven-story building and comparison of ground TDoA with the limit TDoA used in the transportation industry for ride comfort. Some potential impacts of TDoA on humans have also been reviewed.

  6. Compensation Techniques in Accelerator Physics

    Energy Technology Data Exchange (ETDEWEB)

    Sayed, Hisham Kamal [Old Dominion Univ., Norfolk, VA (United States)

    2011-05-01

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

  7. GPU-Accelerated Text Mining

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Xiaohui [ORNL; Mueller, Frank [North Carolina State University; Zhang, Yongpeng [ORNL; Potok, Thomas E [ORNL

    2009-01-01

    Accelerating hardware devices represent a novel promise for improving the performance for many problem domains but it is not clear for which domains what accelerators are suitable. While there is no room in general-purpose processor design to significantly increase the processor frequency, developers are instead resorting to multi-core chips duplicating conventional computing capabilities on a single die. Yet, accelerators offer more radical designs with a much higher level of parallelism and novel programming environments. This present work assesses the viability of text mining on CUDA. Text mining is one of the key concepts that has become prominent as an effective means to index the Internet, but its applications range beyond this scope and extend to providing document similarity metrics, the subject of this work. We have developed and optimized text search algorithms for GPUs to exploit their potential for massive data processing. We discuss the algorithmic challenges of parallelization for text search problems on GPUs and demonstrate the potential of these devices in experiments by reporting significant speedups. Our study may be one of the first to assess more complex text search problems for suitability for GPU devices, and it may also be one of the first to exploit and report on atomic instruction usage that have recently become available in NVIDIA devices.

  8. GPU-Accelerated Text Mining

    International Nuclear Information System (INIS)

    Accelerating hardware devices represent a novel promise for improving the performance for many problem domains but it is not clear for which domains what accelerators are suitable. While there is no room in general-purpose processor design to significantly increase the processor frequency, developers are instead resorting to multi-core chips duplicating conventional computing capabilities on a single die. Yet, accelerators offer more radical designs with a much higher level of parallelism and novel programming environments. This present work assesses the viability of text mining on CUDA. Text mining is one of the key concepts that has become prominent as an effective means to index the Internet, but its applications range beyond this scope and extend to providing document similarity metrics, the subject of this work. We have developed and optimized text search algorithms for GPUs to exploit their potential for massive data processing. We discuss the algorithmic challenges of parallelization for text search problems on GPUs and demonstrate the potential of these devices in experiments by reporting significant speedups. Our study may be one of the first to assess more complex text search problems for suitability for GPU devices, and it may also be one of the first to exploit and report on atomic instruction usage that have recently become available in NVIDIA devices

  9. Analytical tools in accelerator physics

    Energy Technology Data Exchange (ETDEWEB)

    Litvinenko, V.N.

    2010-09-01

    This paper is a sub-set of my lectures presented in the Accelerator Physics course (USPAS, Santa Rosa, California, January 14-25, 2008). It is based on my notes I wrote during period from 1976 to 1979 in Novosibirsk. Only few copies (in Russian) were distributed to my colleagues in Novosibirsk Institute of Nuclear Physics. The goal of these notes is a complete description starting from the arbitrary reference orbit, explicit expressions for 4-potential and accelerator Hamiltonian and finishing with parameterization with action and angle variables. To a large degree follow logic developed in Theory of Cyclic Particle Accelerators by A.A.Kolmensky and A.N.Lebedev [Kolomensky], but going beyond the book in a number of directions. One of unusual feature is these notes use of matrix function and Sylvester formula for calculating matrices of arbitrary elements. Teaching the USPAS course motivated me to translate significant part of my notes into the English. I also included some introductory materials following Classical Theory of Fields by L.D. Landau and E.M. Liftsitz [Landau]. A large number of short notes covering various techniques are placed in the Appendices.

  10. Acceleration of black hole universe

    Science.gov (United States)

    Zhang, T. X.; Frederick, C.

    2014-01-01

    Recently, Zhang slightly modified the standard big bang theory and developed a new cosmological model called black hole universe, which is consistent with Mach's principle, governed by Einstein's general theory of relativity, and able to explain all observations of the universe. Previous studies accounted for the origin, structure, evolution, expansion, and cosmic microwave background radiation of the black hole universe, which grew from a star-like black hole with several solar masses through a supermassive black hole with billions of solar masses to the present state with hundred billion-trillions of solar masses by accreting ambient matter and merging with other black holes. This paper investigates acceleration of the black hole universe and provides an alternative explanation for the redshift and luminosity distance measurements of type Ia supernovae. The results indicate that the black hole universe accelerates its expansion when it accretes the ambient matter in an increasing rate. In other words, i.e., when the second-order derivative of the mass of the black hole universe with respect to the time is positive . For a constant deceleration parameter , we can perfectly explain the type Ia supernova measurements with the reduced chi-square to be very close to unity, χ red˜1.0012. The expansion and acceleration of black hole universe are driven by external energy.

  11. Accelerated Cure Project for Multiple Sclerosis

    Science.gov (United States)

    ... main content Accelerating research toward a cure for multiple sclerosis Home Contact Us Search form Search Connect Volunteer ... is to accelerate efforts toward a cure for multiple sclerosis by rapidly advancing research that determines its causes ...

  12. Berkeley Lab Laser Accelerator (BELLA) facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Berkeley Lab Laser Accelerator (BELLA) facility (formerly LOASIS) develops advanced accelerators and radiation sources. High gradient (1-100 GV/m) laser-plasma...

  13. On the solutions to accelerating cosmologies

    CERN Document Server

    Ito, M

    2003-01-01

    Motivated by recent accelerating cosmological model, we derive the solutions to vacuum Einstein equation in $(d+1)$-dimensional Minkowski space with $n$-dimensional hyperbolic manifold. The conditions of accelerating expansion are given in such a set up.

  14. A Critical Theory Perspective on Accelerated Learning.

    Science.gov (United States)

    Brookfield, Stephen D.

    2003-01-01

    Critically analyzes accelerated learning using concepts from Herbert Marcuse (rebellious subjectivity) and Erich Fromm (automaton conformity). Concludes that, by providing distance and separation, accelerated learning has more potential to stimulate critical autonomous thought. (SK)

  15. Snowmass 2013 Computing Frontier: Accelerator Science

    CERN Document Server

    Spentzouris, P; Joshi, C; Amundson, J; An, W; Bruhwiler, D L; Cary, J R; Cowan, B; Decyk, V K; Esarey, E; Fonseca, R A; Friedman, A; Geddes, C G R; Grote, D P; Kourbanis, I; Leemans, W P; Lu, W; Mori, W B; Ng, C; Qiang, Ji; Roberts, T; Ryne, R D; Schroeder, C B; Silva, L O; Tsung, F S; Vay, J -L; Vieira, J

    2013-01-01

    This is the working summary of the Accelerator Science working group of the Computing Frontier of the Snowmass meeting 2013. It summarizes the computing requirements to support accelerator technology in both Energy and Intensity Frontiers.

  16. EM Structure Based and Vacuum Acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Colby, E.R.; /SLAC

    2005-09-27

    The importance of particle acceleration may be judged from the number of applications which require some sort of accelerated beam. In addition to accelerator-based high energy physics research, non-academic applications include medical imaging and treatment, structural biology by x-ray diffraction, pulse radiography, cargo inspection, material processing, food and medical instrument sterilization, and so on. Many of these applications are already well served by existing technologies and will profit only marginally from developments in accelerator technology. Other applications are poorly served, such as structural biology, which is conducted at synchrotron radiation facilities, and medical treatment using proton accelerators, the machines for which are rare because they are complex and costly. Developments in very compact, high brightness and high gradient accelerators will change how accelerators are used for such applications, and potentially enable new ones. Physical and technical issues governing structure-based and vacuum acceleration of charged particles are reviewed, with emphasis on practical aspects.

  17. Research needs of the new accelerator technologies

    International Nuclear Information System (INIS)

    A review is given of some of the new accelerator technologies with a special eye to the requirements which they generate for research and development. Some remarks are made concerning the organizational needs of accelerator research

  18. Symposium report on frontier applications of accelerators

    International Nuclear Information System (INIS)

    This report contains viewgraph material on the following topics: Electron-Positron Linear Colliders; Unconventional Colliders; Prospects for UVFEL; Accelerator Based Intense Spallation; Neutron Sources; and B Physics at Hadron Accelerators with RHIC as an Example

  19. Symposium report on frontier applications of accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Parsa, Z. [ed.

    1993-09-28

    This report contains viewgraph material on the following topics: Electron-Positron Linear Colliders; Unconventional Colliders; Prospects for UVFEL; Accelerator Based Intense Spallation; Neutron Sources; and B Physics at Hadron Accelerators with RHIC as an Example.

  20. MAFIA study of the RFQ1 accelerator

    Science.gov (United States)

    Adams, F. P.; de Jong, M. S.; Hutcheon, R. M.

    1991-05-01

    The RFQ1 accelerator has been modeled using the MAFIA codes. Calculated resonant frequency shifts due to the introduction of components into the accelerator agree reasonably well with measurements. Heating predictions based on calculated results correspond well with observations.

  1. Conception design of helium ion FFAG accelerator with induction accelerating cavity

    CERN Document Server

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

    2013-01-01

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

  2. Heavy ion accelerators for inertial fusion

    International Nuclear Information System (INIS)

    Particle accelerators are used for accelerating the elementary, stable and separable constituents of matters to relativistic speed. These beams are of fundamental interest in the study on the ultimate constituents of matters and their interaction. Particle accelerators are the most promising driver for the fusion power reactors based on inertial confinement. The principle of inertial confinement fusion, radiation driven indirect drive, the accelerator complex and so on are described. (K.I.)

  3. Conceptual and technological evolutions of particle accelerators

    Institute of Scientific and Technical Information of China (English)

    Lee C.Teng

    2009-01-01

    We give here an ordered list of all types of particle accelerators and exhibit how each type evolves conceptually and/or technologically from the preceding.This is in contrast to the usual "history of particle accelerators" in which unrelated accelerator types are listed in the chronological order.It is hoped that this discussion and understanding of the rationale and logic in the evolution of one accelerator type to the next will help to educe future inventions.

  4. Double layers are not particle accelerators

    International Nuclear Information System (INIS)

    It is pointed out that the continuing advocacy of electrostatic double layers as particle accelerators in the aurora and other space and astrophysical plasmas is fundamentally unsound. It is suggested furthermore that there is little reason to invoke static or quasi-static electric fields as the cause of auroral electron acceleration. Stochastic acceleration by electrostatic wave turbulence appears to present a natural explanation for this and for electron acceleration in other space and astrophysical plasmas. (author)

  5. Accelerated graph-based nonlinear denoising filters

    OpenAIRE

    Knyazev, Andrew; Malyshev, Alexander,

    2015-01-01

    Denoising filters, such as bilateral, guided, and total variation filters, applied to images on general graphs may require repeated application if noise is not small enough. We formulate two acceleration techniques of the resulted iterations: conjugate gradient method and Nesterov's acceleration. We numerically show efficiency of the accelerated nonlinear filters for image denoising and demonstrate 2-12 times speed-up, i.e., the acceleration techniques reduce the number of iterations required...

  6. Acceleration of the FERM nodal program

    International Nuclear Information System (INIS)

    It was tested three acceleration methods trying to reduce the number of outer iterations in the FERM nodal program. The results obtained indicated that the Chebychev polynomial acceleration method with variable degree results in a economy of 50% in the computer time. Otherwise, the acceleration method by source asymptotic extrapolation or by zonal rebalance did not result in economy of the global computer time, however some acceleration had been verified in outer iterations. (M.C.K.)

  7. Acceleration of the nodal program FERM

    International Nuclear Information System (INIS)

    Acceleration of the nodal FERM was tried by three acceleration schemes. Results of the calculations showed the best acceleration with the Tchebyshev method where the savings in the computing time were of the order of 50%. Acceleration with the Assymptotic Source Extrapoltation Method and with the Coarse-Mesh Rebalancing Method did not result in any improvement on the global computational time, although a reduction in the number of outer iterations was observed. (Author)

  8. On accelerated clocks and the quantum theory

    International Nuclear Information System (INIS)

    It is shown that the locality hypothesis of relativity breaks down for large proper accelerations which are relevant to semiclassical phenomena. A general modification for the rate of accelerated clocks incorporating the effect of proper acceleration is thus proposed. Connection is made with Caianiello's quantum line element

  9. Particle acceleration by combined diffusive shock acceleration and downstream multiple magnetic island acceleration

    Science.gov (United States)

    Zank, G. P.; Hunana, P.; Mostafavi, P.; le Roux, J. A.; Li, Gang; Webb, G. M.; Khabarova, O.

    2015-09-01

    As a consequence of the evolutionary conditions [28; 29], shock waves can generate high levels of downstream vortical turbulence. Simulations [32-34] and observations [30; 31] support the idea that downstream magnetic islands (also called plasmoids or flux ropes) result from the interaction of shocks with upstream turbulence. Zank et al. [18] speculated that a combination of diffusive shock acceleration (DSA) and downstream reconnection-related effects associated with the dynamical evolution of a “sea of magnetic islands” would result in the energization of charged particles. Here, we utilize the transport theory [18; 19] for charged particles propagating diffusively in a turbulent region filled with contracting and reconnecting plasmoids and small-scale current sheets to investigate a combined DSA and downstream multiple magnetic island charged particle acceleration mechanism. We consider separately the effects of the anti-reconnection electric field that is a consequence of magnetic island merging [17], and magnetic island contraction [14]. For the merging plasmoid reconnection- induced electric field only, we find i) that the particle spectrum is a power law in particle speed, flatter than that derived from conventional DSA theory, and ii) that the solution is constant downstream of the shock. For downstream plasmoid contraction only, we find that i) the accelerated particle spectrum is a power law in particle speed, flatter than that derived from conventional DSA theory; ii) for a given energy, the particle intensity peaks downstream of the shock, and the peak location occurs further downstream of the shock with increasing particle energy, and iii) the particle intensity amplification for a particular particle energy, f(x, c/c0)/f(0, c/c0), is not 1, as predicted by DSA theory, but increases with increasing particle energy. These predictions can be tested against observations of electrons and ions accelerated at interplanetary shocks and the heliospheric

  10. Wandering accelerators throughout my life (2)

    International Nuclear Information System (INIS)

    My wandering about accelerator started from a van de Graaff accelerator on the Nakanoshima campus of Osaka University. The accelerator was originally designed by Prof. K. Husimi before the World-War II, and completed by Prof. K. Sugimoto, under the severe financial difficulties after the war. It was almost totally handmade, and consequently we were very well trained through various experiences fighting with difficulties. After finishing thesis work, I moved to Berkeley and enjoyed heavy-ion experiments at the world best heavy-ion accelerator, HILAC. The heavy-ion accelerator revealed new facets of nuclei through studies of high-spin states and phenomena. (author)

  11. High-energy cosmic-ray acceleration

    CERN Document Server

    Bustamante, M; de Paula, W; Duarte Chavez, J A; Gago, A M; Hakobyan, H; Jez, P; Monroy Montañez, J A; Ortiz Velasquez, A; Padilla Cabal, F; Pino Rozas, M; Rodriguez Patarroyo, D J; Romeo, G L; Saldaña-Salazar , U J; Velasquez, M; von Steinkirch, M

    2010-01-01

    We briefly review the basics of ultrahigh-energy cosmic-ray acceleration. The Hillas criterion is introduced as a geometrical criterion that must be fulfilled by potential acceleration sites, and energy losses are taken into account in order to obtain a more realistic scenario. The different available acceleration mechanisms are presented, with special emphasis on Fermi shock acceleration and its prediction of a power-law cosmic-ray energy spectrum. We conclude that first-order Fermi acceleration, though not entirely satisfactory, is the most promising mechanism for explaining the ultra-high-energy cosmic-ray flux.

  12. Implementation of Hardware Accelerators on Zynq

    DEFF Research Database (Denmark)

    Toft, Jakob Kenn

    processors, which has made hardware accelerators an essential part of several datacentres and the worlds fastest super-computers. In this work, two different hardware accelerators were implemented on a Xilinx Zynq SoC platform mounted on the ZedBoard platform. The two accelerators are based on two different...... of the ARM Cortex-9 processor featured on the Zynq SoC, with regard to execution time, power dissipation and energy consumption. The implementation of the hardware accelerators were successful. Use of the Monte Carlo processor resulted in a significant increase in performance. The Telco hardware accelerator...

  13. Accelerator Technology Division progress report, FY 1992

    Energy Technology Data Exchange (ETDEWEB)

    Schriber, S.O.; Hardekopf, R.A.; Heighway, E.A.

    1993-07-01

    This report briefly discusses the following topics: The Ground Test Accelerator Program; Defense Free-Electron Lasers; AXY Programs; A Next Generation High-Power Neutron-Scattering Facility; JAERI OMEGA Project and Intense Neutron Sources for Materials Testing; Advanced Free-Electron Laser Initiative; Superconducting Supercollider; The High-Power Microwave (HPM) Program; Neutral Particle Beam (NPB) Power Systems Highlights; Industrial Partnering; Accelerator Physics and Special Projects; Magnetic Optics and Beam Diagnostics; Accelerator Design and Engineering; Radio-Frequency Technology; Accelerator Theory and Free-Electron Laser Technology; Accelerator Controls and Automation; Very High-Power Microwave Sources and Effects; and GTA Installation, Commissioning, and Operations.

  14. Accelerator Technology Division annual report, FY 1991

    International Nuclear Information System (INIS)

    This report discusses the following programs: The Ground Test Accelerator Program; APLE Free-Electron Laser Program; Accelerator Transmutation of Waste; JAERI, OMEGA Project, and Intense Neutron Source for Materials Testing; Advanced Free-Electron Laser Initiative; Superconducting Super Collider; The High-Power Microwave Program; Φ Factory Collaboration; Neutral Particle Beam Power System Highlights; Accelerator Physics and Special Projects; Magnetic Optics and Beam Diagnostics; Accelerator Design and Engineering; Radio-Frequency Technology; Free-Electron Laser Technology; Accelerator Controls and Automation; Very High-Power Microwave Sources and Effects; and GTA Installation, Commissioning, and Operations

  15. Accelerator Technology Division progress report, FY 1992

    International Nuclear Information System (INIS)

    This report briefly discusses the following topics: The Ground Test Accelerator Program; Defense Free-Electron Lasers; AXY Programs; A Next Generation High-Power Neutron-Scattering Facility; JAERI OMEGA Project and Intense Neutron Sources for Materials Testing; Advanced Free-Electron Laser Initiative; Superconducting Supercollider; The High-Power Microwave (HPM) Program; Neutral Particle Beam (NPB) Power Systems Highlights; Industrial Partnering; Accelerator Physics and Special Projects; Magnetic Optics and Beam Diagnostics; Accelerator Design and Engineering; Radio-Frequency Technology; Accelerator Theory and Free-Electron Laser Technology; Accelerator Controls and Automation; Very High-Power Microwave Sources and Effects; and GTA Installation, Commissioning, and Operations

  16. Accelerated Adaptive MGS Phase Retrieval

    Science.gov (United States)

    Lam, Raymond K.; Ohara, Catherine M.; Green, Joseph J.; Bikkannavar, Siddarayappa A.; Basinger, Scott A.; Redding, David C.; Shi, Fang

    2011-01-01

    The Modified Gerchberg-Saxton (MGS) algorithm is an image-based wavefront-sensing method that can turn any science instrument focal plane into a wavefront sensor. MGS characterizes optical systems by estimating the wavefront errors in the exit pupil using only intensity images of a star or other point source of light. This innovative implementation of MGS significantly accelerates the MGS phase retrieval algorithm by using stream-processing hardware on conventional graphics cards. Stream processing is a relatively new, yet powerful, paradigm to allow parallel processing of certain applications that apply single instructions to multiple data (SIMD). These stream processors are designed specifically to support large-scale parallel computing on a single graphics chip. Computationally intensive algorithms, such as the Fast Fourier Transform (FFT), are particularly well suited for this computing environment. This high-speed version of MGS exploits commercially available hardware to accomplish the same objective in a fraction of the original time. The exploit involves performing matrix calculations in nVidia graphic cards. The graphical processor unit (GPU) is hardware that is specialized for computationally intensive, highly parallel computation. From the software perspective, a parallel programming model is used, called CUDA, to transparently scale multicore parallelism in hardware. This technology gives computationally intensive applications access to the processing power of the nVidia GPUs through a C/C++ programming interface. The AAMGS (Accelerated Adaptive MGS) software takes advantage of these advanced technologies, to accelerate the optical phase error characterization. With a single PC that contains four nVidia GTX-280 graphic cards, the new implementation can process four images simultaneously to produce a JWST (James Webb Space Telescope) wavefront measurement 60 times faster than the previous code.

  17. A nanosecond pulsed accelerator facility

    International Nuclear Information System (INIS)

    The operation and performance of a 3-MeV pulsed electrostatic generator producing 1-ns (10-9 s) pulses is described. The system employs terminal pulsing and post-acceleration time-compression to achieve short pulses and high average current. The specifications for this system were based on the following considerations. A 10-μA average beam current represents a reasonable limit based on the ability of a target to dissipate beam power, the 1-ns pulse-length was consistent with other factors such as detector response, energy homogeneity, etc. which determine over-all time resolution, and a repetition rate of 1 MHz/s gives a duty factor consistent with the current capabilities of existing accelerator ion sources. The system consists of a terminal pulsing component which produces pulses of 10 ns in duration by sweeping a beam over an aperture located at the entrance to an accelerator tube. An average output of a current of 10 μA requires a source capable of producing 1 mA of atomic ions. After acceleration this pulse is compressed to 1 ns by the scheme suggested by Mobley. This involves sweeping the beam with proper synchronization across the aperture of a 90o doubly-focusing deflection magnet so that the early portion of the pulse travels through a longer trajectory thani the later portions, thus achieving time compression when the beam is brought to a focus on a suitable target. The radius of beam curvature in the compression magnet is 30 in and the over-all beam divergence at the target is 5o. The choice of these parameters and the effect of the deflection scheme in the beam-energy homogeneity will be discussed. Using existing nanosecond detector techniques, this system has produced over-all system resolutions of 1 ns full-width at half-maximum for both gamma rays and neutrons. It is not yet known what component or components of the system determine the limits on the time resolution of the system. As a facility for investigating neutron inelastic scattering and

  18. Technical report on the accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Bex, L. [ed.

    1995-12-31

    GANIL operation and the technical studies performed in 1994 are described. The milestones for 1994 are: SISSI (Source d`Ions Secondaires a Supraconducteurs Intense) has been in operation and used for secondary beam production with four different primary beams. The 100 kV platform for beam injection in the CO1 has been in operation for production of metallic beams which demand is increasing. Finally the SPIRAL project (Systeme de Production d`Ions Radioactifs Acceleres en Ligne) is in progress. In late 1994 the civil work has started in view of the installation of the machine in the north part of the GANIL machine building. (K.A.). 48 refs.

  19. ACCELERATION GROWTH OF ICT MARKET

    Directory of Open Access Journals (Sweden)

    Drakulić Danica

    2007-06-01

    Full Text Available The wurk points to the importance of ICT (Information Communication Technologies, as one of the main trajectories by which advanced economies have come to the high dynamism and richness. How do the performsnces of these technological changes, determined mainly by ICT, exert influences on the economicgrowth or, in general, on production results at the aggregate, macroeconomic level. The U.S.A. supremacy in this field has faced challenges. It loses tempo, and the EU countries, after the multi-decade syndrome of technological catching up to U.S.A., go through faster into the future, giving an accelerating tone to the technological race.

  20. Accelerator Neutrino Programme at FERMILAB

    International Nuclear Information System (INIS)

    The accelerator neutrino programme in the USA consists primarily of the Fermilab neutrino programme. Currently, Fermilab operates two neutrino beamlines, the Booster neutrino beamline and the NuMI neutrino beamline and is the planning stages for a third neutrino beam to send neutrinos to DUSEL. The experiments in the Booster neutrino beamline are miniBooNE, SciBooNE and in the future microBooNE, whereas in the NuMI beamline we have MINOS, ArgoNut, MINERVA and coming soon NOA. The major experiment in the beamline to DUSEL will be LBNE. (author)

  1. Cosmic acceleration without dark energy

    International Nuclear Information System (INIS)

    In this work, we investigate the global dynamics of the universe within the framework of the Interacting Dark Matter (IDM) scenario. Considering that the dark matter obeys the collisional Boltzmann equation, we can obtain analytical solutions of the global density evolution, which can accommodate an accelerated expansion, equivalent to either the quintessence or the standard Λ models. This is possible if there is a disequilibrium between the DM particle creation and annihilation processes with the former process dominating, which creates an effective source term with negative pressure. We also find realistic solutions in which the present time is located after the inflection point.

  2. Feedback: Theory and Accelerator Applications

    Science.gov (United States)

    Himel, T.

    The use of feedback to stabilize the beam and improve the performance of accelerators is becoming more common. The methods used to design the feedback algorithms are introduced and some practical implementation details are described. The design of a PID loop using classical control techniques is covered as is the design of an optimal controller using modern control theory. Some adaptive control techniques are also briefly described. Examples are given of multiple-input-multiple-output loops and of how to handle systems of many interacting feedback loops.

  3. Accelerator management system using GIS

    International Nuclear Information System (INIS)

    We developed accelerator management systems using Web-based GIS (Geographical Information Systems). GIS unifies location related data like position of equipment, drawings, images etc. and displays them on interactive map on web browsers. GIS can be used various phenomena, machine management, map-drawing management, asset management and scheduler etc. We build two systems, one is equipment management system of SPring-8 and another is real-time alarm display system for SCSS prototype 250 MeV linac. We describe those systems in this paper. (author)

  4. AESS: Accelerated Exact Stochastic Simulation

    Science.gov (United States)

    Jenkins, David D.; Peterson, Gregory D.

    2011-12-01

    The Stochastic Simulation Algorithm (SSA) developed by Gillespie provides a powerful mechanism for exploring the behavior of chemical systems with small species populations or with important noise contributions. Gene circuit simulations for systems biology commonly employ the SSA method, as do ecological applications. This algorithm tends to be computationally expensive, so researchers seek an efficient implementation of SSA. In this program package, the Accelerated Exact Stochastic Simulation Algorithm (AESS) contains optimized implementations of Gillespie's SSA that improve the performance of individual simulation runs or ensembles of simulations used for sweeping parameters or to provide statistically significant results. Program summaryProgram title: AESS Catalogue identifier: AEJW_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEJW_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: University of Tennessee copyright agreement No. of lines in distributed program, including test data, etc.: 10 861 No. of bytes in distributed program, including test data, etc.: 394 631 Distribution format: tar.gz Programming language: C for processors, CUDA for NVIDIA GPUs Computer: Developed and tested on various x86 computers and NVIDIA C1060 Tesla and GTX 480 Fermi GPUs. The system targets x86 workstations, optionally with multicore processors or NVIDIA GPUs as accelerators. Operating system: Tested under Ubuntu Linux OS and CentOS 5.5 Linux OS Classification: 3, 16.12 Nature of problem: Simulation of chemical systems, particularly with low species populations, can be accurately performed using Gillespie's method of stochastic simulation. Numerous variations on the original stochastic simulation algorithm have been developed, including approaches that produce results with statistics that exactly match the chemical master equation (CME) as well as other approaches that approximate the CME. Solution

  5. UCLA accelerator research and development

    International Nuclear Information System (INIS)

    This progress report covers work supported by the above DOE grant over the period November 1, 1991 to July 31, 1992. The work is a program of experimental and theoretical studies in advanced particle accelerator research and development for high energy physics applications. The program features research at particle beam facilities in the United States and includes research on novel high power sources, novel focussing systems (e.g. plasma lens), beam monitors, novel high brightness, high current gun systems, and novel flavor factories in particular the φ Factory

  6. Electron Acceleration by Transient Ion Foreshock Phenomena

    Science.gov (United States)

    Wilson, L. B., III; Turner, D. L.

    2015-12-01

    Particle acceleration is a topic of considerable interest in space, laboratory, and astrophysical plasmas as it is a fundamental physical process to all areas of physics. Recent THEMIS [e.g., Turner et al., 2014] and Wind [e.g., Wilson et al., 2013] observations have found evidence for strong particle acceleration at macro- and meso-scale structures and/or pulsations called transient ion foreshock phenomena (TIFP). Ion acceleration has been extensively studied, but electron acceleration has received less attention. Electron acceleration can arise from fundamentally different processes than those affecting ions due to differences in their gyroradii. Electron acceleration is ubiquitous, occurring in the solar corona (e.g., solar flares), magnetic reconnection, at shocks, astrophysical plasmas, etc. We present new results analyzing the dependencies of electron acceleration on the properties of TIFP observed by the THEMIS spacecraft.

  7. Microwave View on Particle Acceleration in Flares

    CERN Document Server

    Fleishman, Gregory D

    2013-01-01

    The thermal-to-nonthermal partition was found to vary greatly from one flare to another resulting in a broad variety of cases from 'heating without acceleration' to 'acceleration without heating'. Recent analysis of microwave data of these differing cases suggests that a similar acceleration mechanism, forming a power-law nonthermal tail up to a few MeV or even higher, operates in all the cases. However, the level of this nonthermal spectrum compared to the original thermal distribution differs significantly from one case to another, implying a highly different thermal-to-nonthermal energy partition in various cases. This further requires a specific mechanism capable of extracting the charged particles from the thermal pool and supplying them to a bulk acceleration process to operate in flares \\textit{in addition} to the bulk acceleration process itself, which, in contrast, efficiently accelerates the seed particles, while cannot accelerate the thermal particles. Within this 'microwave' view on the flare ener...

  8. ACFA and IPAC announce accelerator prizes

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    Steve Myers, CERN's Director for Accelerators and Technology. The Asian Committee for Future Accelerators (ACFA) has joined forces with the first International Particle Accelerator Conference, IPAC’10, to award prizes for outstanding work in the field of accelerators. The conference replaces the regional conferences of the Americas, Europe and Asia and will be hosted by the three regions on a rotational basis (see CERN Courier). The ACFA/IPAC’10 Prizes Selection Committee, chaired by Won Namkung of Pohang Accelerator Laboratory, decided on the prizes and the names of the winners at a meeting on 20 January. The awards will be made during IPAC’10, which will be held in Kyoto on 23-28 May. Jie Wei. (Courtesy Tsinghua University.) Steve Myers, Director for Accelerators and Technology at CERN, receives an Achievement Prize for Outstanding Work in the Accelerator Field with no Age Limit “for his numerous outstanding contributions to the design, construction, commissio...

  9. Cosmic-ray acceleration in young protostars

    CERN Document Server

    Padovani, Marco; Marcowith, Alexandre; Ferrière, Katia

    2015-01-01

    The main signature of the interaction between cosmic rays and molecular clouds is the high ionisation degree. This decreases towards the densest parts of a cloud, where star formation is expected, because of energy losses and magnetic effects. However recent observations hint to high levels of ionisation in protostellar systems, therefore leading to an apparent contradiction that could be explained by the presence of energetic particles accelerated within young protostars. Our modelling consists of a set of conditions that has to be satisfied in order to have an efficient particle acceleration through the diffusive shock acceleration mechanism. We find that jet shocks can be strong accelerators of protons which can be boosted up to relativistic energies. Another possibly efficient acceleration site is located at protostellar surfaces, where shocks caused by impacting material during the collapse phase are strong enough to accelerate protons. Our results demonstrate the possibility of accelerating particles du...

  10. Multi-beam linear accelerator EVT

    Science.gov (United States)

    Teryaev, Vladimir E.; Kazakov, Sergey Yu.; Hirshfield, Jay L.

    2016-09-01

    A novel electron multi-beam accelerator is presented. The accelerator, short-named EVT (Electron Voltage Transformer) belongs to the class of two-beam accelerators. It combines an RF generator and essentially an accelerator within the same vacuum envelope. Drive beam-lets and an accelerated beam are modulated in RF modulators and then bunches pass into an accelerating structure, comprising uncoupled with each other and inductive tuned cavities, where the energy transfer from the drive beams to the accelerated beam occurs. A phasing of bunches is solved by choice correspond distances between gaps of the adjacent cavities. Preliminary results of numerical simulations and the initial specification of EVT operating in S-band, with a 60 kV gun and generating a 2.7 A, 1.1 MV beam at its output is presented. A relatively high efficiency of 67% and high design average power suggest that EVT can find its use in industrial applications.

  11. Future HEP Accelerators: The US Perspective

    CERN Document Server

    Bhat, Pushpalatha

    2015-01-01

    Accelerator technology has advanced tremendously since the introduction of accelerators in the 1930s, and particle accelerators have become indispensable instruments in high energy physics (HEP) research to probe Nature at smaller and smaller distances. At present, accelerator facilities can be classified into Energy Frontier colliders that enable direct discoveries and studies of high mass scale particles and Intensity Frontier accelerators for exploration of extremely rare processes, usually at relatively low energies. The near term strategies of the global energy frontier particle physics community are centered on fully exploiting the physics potential of the Large Hadron Collider (LHC) at CERN through its high-luminosity upgrade (HL-LHC), while the intensity frontier HEP research is focused on studies of neutrinos at the MW-scale beam power accelerator facilities, such as Fermilab Main Injector with the planned PIP-II SRF linac project. A number of next generation accelerator facilities have been proposed...

  12. Plasma Channel Guided Laser Wakefield Accelerator

    CERN Document Server

    Geddes, C G

    2005-01-01

    High quality electron beams (several 109 electrons above 80 MeV energy with percent energy spread and low divergence) have been produced for the first time in a compact, high gradient, all-optical laser accelerator by extending the interaction distance using a pre-formed plasma density channel to guide the drive laser pulse. Laser-driven accelerators, in which particles are accelerated by the electric field of a plasma wave (wake) driven by the radiation pressure of an intense laser, have over the past decade demonstrated accelerating fields thousands of times greater than those achievable in conventional radio-frequency accelerators. This has spurred interest in them as compact next- generation sources of energetic electrons and radiation. To date, however, acceleration distances have been severely limited by the lack of a controllable method for extending the propagation distance of the focused laser pulse. The ensuing short acceleration distance resulted in low-energy beams with 100 percent electron energy...

  13. Community Petascale Project for Accelerator Science and Simulation: Advancing Computational Science for Future Accelerators and Accelerator Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Spentzouris, P.; /Fermilab; Cary, J.; /Tech-X, Boulder; McInnes, L.C.; /Argonne; Mori, W.; /UCLA; Ng, C.; /SLAC; Ng, E.; Ryne, R.; /LBL, Berkeley

    2011-11-14

    The design and performance optimization of particle accelerators are essential for the success of the DOE scientific program in the next decade. Particle accelerators are very complex systems whose accurate description involves a large number of degrees of freedom and requires the inclusion of many physics processes. Building on the success of the SciDAC-1 Accelerator Science and Technology project, the SciDAC-2 Community Petascale Project for Accelerator Science and Simulation (ComPASS) is developing a comprehensive set of interoperable components for beam dynamics, electromagnetics, electron cooling, and laser/plasma acceleration modelling. ComPASS is providing accelerator scientists the tools required to enable the necessary accelerator simulation paradigm shift from high-fidelity single physics process modeling (covered under SciDAC1) to high-fidelity multiphysics modeling. Our computational frameworks have been used to model the behavior of a large number of accelerators and accelerator R&D experiments, assisting both their design and performance optimization. As parallel computational applications, the ComPASS codes have been shown to make effective use of thousands of processors. ComPASS is in the first year of executing its plan to develop the next-generation HPC accelerator modeling tools. ComPASS aims to develop an integrated simulation environment that will utilize existing and new accelerator physics modules with petascale capabilities, by employing modern computing and solver technologies. The ComPASS vision is to deliver to accelerator scientists a virtual accelerator and virtual prototyping modeling environment, with the necessary multiphysics, multiscale capabilities. The plan for this development includes delivering accelerator modeling applications appropriate for each stage of the ComPASS software evolution. Such applications are already being used to address challenging problems in accelerator design and optimization. The ComPASS organization

  14. Intermittent sea-level acceleration

    Science.gov (United States)

    Olivieri, M.; Spada, G.

    2013-10-01

    Using instrumental observations from the Permanent Service for Mean Sea Level (PSMSL), we provide a new assessment of the global sea-level acceleration for the last ~ 2 centuries (1820-2010). Our results, obtained by a stack of tide gauge time series, confirm the existence of a global sea-level acceleration (GSLA) and, coherently with independent assessments so far, they point to a value close to 0.01 mm/yr2. However, differently from previous studies, we discuss how change points or abrupt inflections in individual sea-level time series have contributed to the GSLA. Our analysis, based on methods borrowed from econometrics, suggests the existence of two distinct driving mechanisms for the GSLA, both involving a minority of tide gauges globally. The first effectively implies a gradual increase in the rate of sea-level rise at individual tide gauges, while the second is manifest through a sequence of catastrophic variations of the sea-level trend. These occurred intermittently since the end of the 19th century and became more frequent during the last four decades.

  15. Particle Accelerators for PET radionuclides

    DEFF Research Database (Denmark)

    Jensen, Mikael

    2012-01-01

    The requirements set for particle accelerators for production of radioactive isotopes for PET can easily be derived from first principles. The simple general need is for proton beams with energy in the region 10–20 MeV and current 20–100 microAmps. This is most reliably and cost-effectively achie......The requirements set for particle accelerators for production of radioactive isotopes for PET can easily be derived from first principles. The simple general need is for proton beams with energy in the region 10–20 MeV and current 20–100 microAmps. This is most reliably and cost...... different manufacturers will be discussed the light of what is actually needed for a given PET site operation. Alternatives to the conventional cyclotron have been proposed and tested but have at present very limited use. These alternatives will be discussed, as well as the future possibilities of supplying...... point of demand tracer production with very small cyclotrons of energy well below 10 MeV. The authors best advice at present for new PET sites is to negotiate for conventional cyclotron solutions from experienced manufacturers. It is the combined performance of cyclotron and target in terms of available...

  16. Winter therapy for the accelerators

    CERN Multimedia

    Corinne Pralavorio

    2016-01-01

    Hundreds of people are hard at work during the year-end technical stop as all the accelerators are undergoing maintenance, renovation and upgrade operations in parallel.   The new beam absorber on its way to Point 2 before being lowered into the LHC tunnel for installation. The accelerator teams didn’t waste any time before starting their annual winter rejuvenation programme over the winter. At the end of November, as the LHC ion run was beginning, work got under way on the PS Booster, where operation had already stopped. On 14 December, once the whole complex had been shut down, the technical teams turned their attention to the other injectors and the LHC. The year-end technical stop (YETS) provides an opportunity to carry out maintenance work on equipment and repair any damage as well as to upgrade the machines for the upcoming runs. Numerous work projects are carried out simultaneously, so good coordination is crucial. Marzia Bernardini's team in the Enginee...

  17. Ponderomotive Acceleration in Coronal Loops

    CERN Document Server

    Dahlburg, R B; Taylor, B D; Obenschain, K

    2016-01-01

    Ponderomotive acceleration has been asserted to be a cause of the First Ionization Potential (FIP) effect, the by now well known enhancement in abundance by a factor of 3-4 over photospheric values of elements in the solar corona with FIP less than about 10 eV. It is shown here by means of numerical simulations that ponderomotive acceleration occurs in solar coronal loops, with the appropriate magnitude and direction, as a "byproduct" of coronal heating. The numerical simulations are performed with the HYPERION code, which solves the fully compressible three-dimensional magnetohydrodynamic equations including nonlinear thermal conduction and optically thin radiation. Numerical simulations of a coronal loops with an axial magnetic field from 0.005 Teslas to 0.02 Teslas and lengths from 25000 km to 75000 km are presented. In the simulations the footpoints of the axial loop magnetic field are convected by random, large-scale motions. There is a continuous formation and dissipation of field-aligned current sheets...

  18. Testing general relativity on accelerators

    Directory of Open Access Journals (Sweden)

    Tigran Kalaydzhyan

    2015-11-01

    Full Text Available Within the general theory of relativity, the curvature of spacetime is related to the energy and momentum of the present matter and radiation. One of the more specific predictions of general relativity is the deflection of light and particle trajectories in the gravitational field of massive objects. Bending angles for electromagnetic waves and light in particular were measured with a high precision. However, the effect of gravity on relativistic massive particles was never studied experimentally. Here we propose and analyze experiments devoted to that purpose. We demonstrate a high sensitivity of the laser Compton scattering at high energy accelerators to the effects of gravity. The main observable – maximal energy of the scattered photons – would experience a significant shift in the ambient gravitational field even for otherwise negligible violation of the equivalence principle. We confirm predictions of general relativity for ultrarelativistic electrons of energy of tens of GeV at a current level of resolution and expect our work to be a starting point of further high-precision studies on current and future accelerators, such as PETRA, European XFEL and ILC.

  19. High Temperature Superconductor Accelerator Magnets

    CERN Document Server

    AUTHOR|(CDS)2079328; de Rijk, Gijs; Dhalle, Marc

    2016-11-10

    For future particle accelerators bending dipoles are considered with magnetic fields exceeding $20T$. This can only be achieved using high temperature superconductors (HTS). These exhibit different properties from classical low temperature superconductors and still require significant research and development before they can be applied in a practical accelerator magnet. In order to study HTS in detail, a five tesla demonstrator magnet named Feather-M2 is designed and constructed. The magnet is based on ReBCO coated conductor, which is assembled into a $10kA$ class Roebel cable. A new and optimized Aligned Block layout is used, which takes advantage of the anisotropy of the conductor. This is achieved by providing local alignment of the Roebel cable in the coil windings with the magnetic field lines. A new Network Model capable of analyzing transient electro-magnetic and thermal phenomena in coated conductor cables and coils is developed. This model is necessary to solve critical issues in coated conductor ac...

  20. heavy ion acceleration at shocks

    Science.gov (United States)

    Shevchenko, V. I.; Galinsky, V.

    2009-12-01

    The theoretical study of alpha particle acceleration at a quasi-parallel shock due to interaction with Alfven waves self-consistently excited in both upstream and downstream regions was conducted using a scale-separation model [1]. The model uses conservation laws and resonance conditions to find where waves will be generated or dumped and hence particles will be pitch--angle scattered as well as the change of the wave energy due to instability or damping. It includes in consideration the total distribution function (the bulk plasma and high energy tail), so no any assumptions (e.g. seed populations, or some ad-hoc escape rate of accelerated particles) are required. In previous studies heavy ions were treated as perfect test particles, they only experienced the Alfven turbulence excited by protons and didn’t contribute to turbulence generation. In contrast to this approach, we consider the ion scattering on hydromagnetic turbulence generated by both protons and ions themselves. It is important for alpha particles with their relatively large mass-loading parameter that defines efficiency of the wave excitation by alpha particles. The energy spectra of alpha particles is found and compared with those obtained in test particle approximation. [1] Galinsky, V.L., and V.I. Shevchenko, Astrophys. J., 669, L109, 2007.

  1. Testing general relativity on accelerators

    Science.gov (United States)

    Kalaydzhyan, Tigran

    2015-11-01

    Within the general theory of relativity, the curvature of spacetime is related to the energy and momentum of the present matter and radiation. One of the more specific predictions of general relativity is the deflection of light and particle trajectories in the gravitational field of massive objects. Bending angles for electromagnetic waves and light in particular were measured with a high precision. However, the effect of gravity on relativistic massive particles was never studied experimentally. Here we propose and analyze experiments devoted to that purpose. We demonstrate a high sensitivity of the laser Compton scattering at high energy accelerators to the effects of gravity. The main observable - maximal energy of the scattered photons - would experience a significant shift in the ambient gravitational field even for otherwise negligible violation of the equivalence principle. We confirm predictions of general relativity for ultrarelativistic electrons of energy of tens of GeV at a current level of resolution and expect our work to be a starting point of further high-precision studies on current and future accelerators, such as PETRA, European XFEL and ILC.

  2. Synergia CUDA: GPU-accelerated accelerator modeling package

    Science.gov (United States)

    Lu, Q.; Amundson, J.

    2014-06-01

    Synergia is a parallel, 3-dimensional space-charge particle-in-cell accelerator modeling code. We present our work porting the purely MPI-based version of the code to a hybrid of CPU and GPU computing kernels. The hybrid code uses the CUDA platform in the same framework as the pure MPI solution. We have implemented a lock-free collaborative charge-deposition algorithm for the GPU, as well as other optimizations, including local communication avoidance for GPUs, a customized FFT, and fine-tuned memory access patterns. On a small GPU cluster (up to 4 Tesla C1070 GPUs), our benchmarks exhibit both superior peak performance and better scaling than a CPU cluster with 16 nodes and 128 cores. We also compare the code performance on different GPU architectures, including C1070 Tesla and K20 Kepler.

  3. CAS CERN Accelerator School: Applied geodesy for particle accelerators

    International Nuclear Information System (INIS)

    This specialized course addresses the many topics involved in the application of geodesy to large particle accelerators, though many of the techniques described are equally applicable to large construction projects and surveillance systems where the highest possible surveying accuracies are required. The course reflects the considerable experience gained over many years, not only at CERN but in projects all over the world. The methods described range from the latest approach using satellites to recent developments in conventional techniques. They include the global positioning system (GPS), its development, deployment and precision, the use of the Terrameter and the combination or comparison of its results with those of the GPS, the automation of instruments, the management of measurements and data, and the highly evolved treatment of the observations. (orig.)

  4. Radiative damping in plasma-based accelerators

    Science.gov (United States)

    Kostyukov, I. Yu.; Nerush, E. N.; Litvak, A. G.

    2012-11-01

    The electrons accelerated in a plasma-based accelerator undergo betatron oscillations and emit synchrotron radiation. The energy loss to synchrotron radiation may seriously affect electron acceleration. The electron dynamics under combined influence of the constant accelerating force and the classical radiation reaction force is studied. It is shown that electron acceleration cannot be limited by radiation reaction. If initially the accelerating force was stronger than the radiation reaction force, then the electron acceleration is unlimited. Otherwise the electron is decelerated by radiative damping up to a certain instant of time and then accelerated without limits. It is shown that regardless of the initial conditions the infinite-time asymptotic behavior of an electron is governed by a self-similar solution providing that the radiative damping becomes exactly equal to 2/3 of the accelerating force. The relative energy spread induced by the radiative damping decreases with time in the infinite-time limit. The multistage schemes operating in the asymptotic acceleration regime when electron dynamics is determined by the radiation reaction are discussed.

  5. Conception design of helium ion FFAG accelerator with induction accelerating cavity

    Institute of Scientific and Technical Information of China (English)

    LUO Huan-Li; XU Yu-Cun; WANG Xiang-Qi; XU Hong-Liang

    2013-01-01

    In the recent decades of particle accelerator R&D area,the fixed field alternating gradient (FFAG) accelerator has become a highlight for some advantages of its higher beam intensity and lower cost,although there are still some technical challenges.In this paper,the FFAG accelerator is adopted to accelerate a helium ion beam on the one hand for the study of helium embrittlement on fusion reactor envelope material and on the other hand for promoting the conception research and design of the FFAG accelerator and exploring the possibility of developing high power FFAG accelerators.The conventional period focusing unit of the helium ion FFAG accelerator and threedimensional model of the large aperture combinatorial magnet by OPERA-TOSCA are given.For low energy and low revolution frequency,induction acceleration is proposed to replace conventional radio frequency (RF) acceleration for the helium ion FFAG accelerator,which avoids the potential breakdown of the acceleration field caused by the wake field and improves the acceleration repetition frequency to gain higher beam intensity.The main parameters and three-dimensional model of induction cavity are given.Two special constraint waveforms are proposed to refrain from particle accelerating time slip (AT) caused by accelerating voltage drop of flat top and energy deviation.The particle longitudinal motion in two waveforms is simulated.

  6. Commnity Petascale Project for Accelerator Science And Simulation: Advancing Computational Science for Future Accelerators And Accelerator Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Spentzouris, Panagiotis; /Fermilab; Cary, John; /Tech-X, Boulder; Mcinnes, Lois Curfman; /Argonne; Mori, Warren; /UCLA; Ng, Cho; /SLAC; Ng, Esmond; Ryne, Robert; /LBL, Berkeley

    2011-10-21

    The design and performance optimization of particle accelerators are essential for the success of the DOE scientific program in the next decade. Particle accelerators are very complex systems whose accurate description involves a large number of degrees of freedom and requires the inclusion of many physics processes. Building on the success of the SciDAC-1 Accelerator Science and Technology project, the SciDAC-2 Community Petascale Project for Accelerator Science and Simulation (ComPASS) is developing a comprehensive set of interoperable components for beam dynamics, electromagnetics, electron cooling, and laser/plasma acceleration modelling. ComPASS is providing accelerator scientists the tools required to enable the necessary accelerator simulation paradigm shift from high-fidelity single physics process modeling (covered under SciDAC1) to high-fidelity multiphysics modeling. Our computational frameworks have been used to model the behavior of a large number of accelerators and accelerator R&D experiments, assisting both their design and performance optimization. As parallel computational applications, the ComPASS codes have been shown to make effective use of thousands of processors.

  7. Accelerating Scientific Computations using FPGAs

    Science.gov (United States)

    Pell, O.; Atasu, K.; Mencer, O.

    Field Programmable Gate Arrays (FPGAs) are semiconductor devices that contain a grid of programmable cells, which the user configures to implement any digital circuit of up to a few million gates. Modern FPGAs allow the user to reconfigure these circuits many times each second, making FPGAs fully programmable and general purpose. Recent FPGA technology provides sufficient resources to tackle scientific applications on large-scale parallel systems. As a case study, we implement the Fast Fourier Transform [1] in a flexible floating point implementation. We utilize A Stream Compiler [2] (ASC) which combines C++ syntax with flexible floating point support by providing a 'HWfloat' data-type. The resulting FFT can be targeted to a variety of FPGA platforms in FFTW-style, though not yet completely automatically. The resulting FFT circuit can be adapted to the particular resources available on the system. The optimal implementation of an FFT accelerator depends on the length and dimensionality of the FFT, the available FPGA area, the available hard DSP blocks, the FPGA board architecture, and the precision and range of the application [3]. Software-style object-orientated abstractions allow us to pursue an accelerated pace of development by maximizing re-use of design patterns. ASC allows a few core hardware descriptions to generate hundreds of different circuit variants to meet particular speed, area and precision goals. The key to achieving maximum acceleration of FFT computation is to match memory and compute bandwidths so that maximum use is made of computational resources. Modern FPGAs contain up to hundreds of independent SRAM banks to store intermediate results, providing ample scope for optimizing memory parallelism. At 175Mhz, one of Maxeler's Radix-4 FFT cores computes 4x as many 1024pt FFTs per second as a dual Pentium-IV Xeon machine running FFTW. Eight such parallel cores fit onto the largest FPGA in the Xilinx Virtex-4 family, providing a 32x speed-up over

  8. Radioisotope production with electron accelerators

    International Nuclear Information System (INIS)

    The production of radio isotopes with electron accelerators proceeds mainly by secondary photons (bremsstrahlung), produced in an interaction between the electrons and the Coulomb field of the nuclei of a converter. The production yields depend on: the initial electron energy, the Z and thickness of the bremsstrahlung-converter, the Z, A and the thickness of the target, the geometric set up and the cross section for a particular reaction. In this article the production is only considered for thin bremsstrahlung converters in combination with an electron 'sweep' magnet. Simple formulae are given for the calculations of production yields under standard conditions with only sigmasub(q) (the cross section per equivalent quantum) and f (the fraction of the photons that hit the target) as variables and for the calculations of the dose rate at the production point. The units in which the yields are expressed in the literature (units of sigmasub(q) dose, electron beam intensity, monitor response) are discussed. (Auth.)

  9. Microdischarges in DC accelerator tubes

    International Nuclear Information System (INIS)

    Voltage tests on the Daresbury ceramic/titanium accelerator tube have shown that microdischarges play an important role in the conditioning process. It has been found that the voltage onset for microdischarges in a tube is dependent on the surface contamination of the electrodes and the tube geometry (in particular the tube length). This geometrical effect can be related to the trajectories of secondary ions emitted from the electrode surfaces. Sensitive diagnostic techniques have been developed to study the mass and energy distribution of ions emitted along the axis of the tube during these predischarges. The energy distribution of protons (and H- ions) can be related to the origins of the discharges in the tube. Detailed results are presented for a particular tube geometry. (author)

  10. CLIC Accelerated R&D

    CERN Document Server

    Wilson, Ian H

    2005-01-01

    An accelerated R&D programme to demonstrate the key feasibility issues of the CLIC scheme before 2010 was approved by the CERN Council in March 2004. This report describes the activities, extra resources and time schedule to complete this programme. The activities are presented in the form of work-packages. Laboratories, Universities and Funding Agencies around the world have been invited by the CERN DG to participate in the programme by taking full technical responsibility for part, complete or several work packages and/or providing voluntary contributions "a la carte", in cash, in kind and/or in man-power. The intention is to set-up a multi-lateral collaboration between all laboratories interested in such a development.

  11. GPUs as Storage System Accelerators

    CERN Document Server

    Al-Kiswany, Samer; Ripeanu, Matei

    2012-01-01

    Massively multicore processors, such as Graphics Processing Units (GPUs), provide, at a comparable price, a one order of magnitude higher peak performance than traditional CPUs. This drop in the cost of computation, as any order-of-magnitude drop in the cost per unit of performance for a class of system components, triggers the opportunity to redesign systems and to explore new ways to engineer them to recalibrate the cost-to-performance relation. This project explores the feasibility of harnessing GPUs' computational power to improve the performance, reliability, or security of distributed storage systems. In this context, we present the design of a storage system prototype that uses GPU offloading to accelerate a number of computationally intensive primitives based on hashing, and introduce techniques to efficiently leverage the processing power of GPUs. We evaluate the performance of this prototype under two configurations: as a content addressable storage system that facilitates online similarity detectio...

  12. Microwave-Accelerated Organic Reactions

    Institute of Scientific and Technical Information of China (English)

    LU; TaJung

    2001-01-01

    The use of microwave technology in accelerating organic reactions has received intense attention leading to immense growth recently. Accordingly, we have been interested in improving the efficacy of organic processes by microwave irradiation. Here we report our results on the microwave assisted 1,3-dipolar cycloaddition reaction of nitrile oxides with allylic alcohols, the cleavage reaction of 1,3-diketones under alkaline conditions, and the formation of carbamates from isocyanates with alcohols. The reactions carried out under microwave irradiation, in general, required considerably less reaction time and afforded the desired products in higher yields than those under classical conditions. In all the cases we have studied, the procedures are simplified, the purity of the products are higher, and the cost of reaction is greatly reduced employing microwave.  ……

  13. Microwave-Accelerated Organic Reactions

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ The use of microwave technology in accelerating organic reactions has received intense attention leading to immense growth recently. Accordingly, we have been interested in improving the efficacy of organic processes by microwave irradiation. Here we report our results on the microwave assisted 1,3-dipolar cycloaddition reaction of nitrile oxides with allylic alcohols, the cleavage reaction of 1,3-diketones under alkaline conditions, and the formation of carbamates from isocyanates with alcohols. The reactions carried out under microwave irradiation, in general, required considerably less reaction time and afforded the desired products in higher yields than those under classical conditions. In all the cases we have studied, the procedures are simplified, the purity of the products are higher, and the cost of reaction is greatly reduced employing microwave.

  14. Accelerators for Fusion Materials Testing

    Science.gov (United States)

    Knaster, Juan; Okumura, Yoshikazu

    Fusion materials research is a worldwide endeavor as old as the parallel one working toward the long term stable confinement of ignited plasma. In a fusion reactor, the preservation of the required minimum thermomechanical properties of the in-vessel components exposed to the severe irradiation and heat flux conditions is an indispensable factor for safe operation; it is also an essential goal for the economic viability of fusion. Energy from fusion power will be extracted from the 14 MeV neutron freed as a product of the deuterium-tritium fusion reactions; thus, this kinetic energy must be absorbed and efficiently evacuated and electricity eventually generated by the conventional methods of a thermal power plant. Worldwide technological efforts to understand the degradation of materials exposed to 14 MeV neutron fluxes >1018 m-2s-1, as expected in future fusion power plants, have been intense over the last four decades. Existing neutron sources can reach suitable dpa (“displacement-per-atom”, the figure of merit to assess materials degradation from being exposed to neutron irradiation), but the differences in the neutron spectrum of fission reactors and spallation sources do not allow one to unravel the physics and to anticipate the degradation of materials exposed to fusion neutrons. Fusion irradiation conditions can be achieved through Li (d, xn) nuclear reactions with suitable deuteron beam current and energy, and an adequate flowing lithium screen. This idea triggered in the late 1970s at Los Alamos National Laboratory (LANL) a campaign working toward the feasibility of continuous wave (CW) high current linacs framed by the Fusion Materials Irradiation Test (FMIT) project. These efforts continued with the Low Energy Demonstrating Accelerator (LEDA) (a validating prototype of the canceled Accelerator Production of Tritium (APT) project), which was proposed in 2002 to the fusion community as a 6.7MeV, 100mA CW beam injector for a Li (d, xn) source to bridge

  15. Building bridges … and accelerators

    CERN Multimedia

    2009-01-01

    Lyn Evans, the LHC project leader, was awarded an honorary doctorate from the University of Geneva (UNIGE) to celebrate his role not just in building accelerators, but also in building bridges between nations. He was one of four notables honoured at the event on Friday 5 June, coinciding with the University’s 450th Anniversary. Lyn Evans arriving at the ceremony with Archbishop Desmond Tutu. "It was a big surprise when I found out I’d been nominated," recounts Evans, "but it was an even bigger surprise to find out with whom I’d been nominated". At the ceremony Evans was awarded the honorary doctorate along with three others: Archbishop Desmond Tutu, who was acclaimed for his fight against apartheid in South Africa, Mary Robinson, first woman president of Ireland and former United Nations’ high commissioner of human rights, and Pascal Lamy, Director-General of the World Trade Organization. The award ceremony, known as the �...

  16. Born Reciprocity and Cosmic Accelerations

    CERN Document Server

    Bolognesi, S

    2015-01-01

    The trans-Planckian theory is a model that realizes concretely the Born reciprocity idea, which is the postulate of absolute equivalence between coordinate $x$ and momenta $p$. This model is intrinsically global, and thus it is naturally implemented in a cosmological setting. Cosmology and Born reciprocity are made for each other. Inflation provides the essential mechanism to suppress the terms coming from the dual part of the action. The trans-Planckian theory, on the other hand, provides an explanation for the accelerated periods of the universe scale factor, both the inflationary period and the present period dominated by dark energy. All of this is possible just considering a simple model that contains gravity, one gauge field plus one matter field (to be identified with dark matter) together with the reciprocity principle.

  17. FEL-accelerator related diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Kevin Jordan; David Douglas; Stephen V. Benson; Pavel Evtuschenko

    2007-08-02

    Free Electron Lasers (FEL) present a unique set of beam parameters to the diagnostics suite. The FEL requires characterization of the full six dimensional phase space of the electron beam at the wiggler and accurate alignment of the electron beam to the optical mode of the laser. In addition to the FEL requirements on the diagnostics suite, the Jefferson Lab FEL is operated as an Energy Recovered Linac (ERL) which imposes additional requirements on the diagnostics. The ERL aspect of the Jefferson Lab FEL requires that diagnostics operate over a unique dynamic range and operate with simultaneous transport of the accelerated and energy recovered beams. This talk will present how these challenges are addressed at the Jefferson Lab FEL.

  18. Accelerating the life of transistors

    Institute of Scientific and Technical Information of China (English)

    Qi Haochun; Lü Changzhi; Zhang Xiaoling; Xie Xuesong

    2013-01-01

    Choosing small and medium power switching transistors of the NPN type in a 3DK set as the study object,the test of accelerating life is conducted in constant temperature and humidity,and then the data are statistically analyzed with software developed by ourselves.According to degradations of such sensitive parameters as the reverse leakage current of transistors,the lifetime order of transistors is about more than 104 at 100 ℃ and 100% relative humidity (RH) conditions.By corrosion fracture of transistor outer leads and other failure modes,with the failure truncated testing,the average lifetime rank of transistors in different distributions is extrapolated about 103.Failure mechanism analyses of degradation of electrical parameters,outer lead fracture and other reasons that affect transistor lifetime are conducted.The findings show that the impact of external stress of outer leads on transistor reliability is more serious than that of parameter degradation.

  19. Sealed ion accelerator tubes (survey)

    International Nuclear Information System (INIS)

    The first publications on developing commercial models of small-scale sealed accelerator tubes in which neutrons are generated appeared in the foreign press in 1954 to 1957; they were very brief and were advertising-oriented. The tubes were designed for neutron logging of oil wells instead of ampule neutron sources (Po + Be, Ra + Be). Later, instruments of this type began to be called neutron tubes from the resulting neutron radiation that they gave off. In Soviet Union a neutron tube was developed in 1958 in connection with the development of the pulsed neutron-neutron method of studying the geological profile of oil wells. At that time the tube developed was intended, in the view of its inventors, to replace standard isotope sources with constant neutron yield. A fairly detailed survey of neutron tubes was made in the studies. 8 refs., 8 figs

  20. Accelerator system for neutron radiography

    International Nuclear Information System (INIS)

    The field of x-ray radiography is well established for doing non-destructive evaluation of a vast array of components, assemblies, and objects. While x-rays excel in many radiography applications, their effectiveness diminishes rapidly if the objects of interest are surrounded by thick, high-density materials that strongly attenuate photons. Due to the differences in interaction mechanisms, neutron radiography is highly effective in imaging details inside such objects. To obtain a high intensity neutron source suitable for neutron imaging a 9-MeV linear accelerator is being evaluated for putting a deuteron beam into a high-pressure deuterium gas cell. As a windowless aperture is needed to transport the beam into the gas cell, a low-emittance is needed to minimize losses along the high-energy beam transport (HEBT) and the end station. A description of the HEBT, the transport optics into the gas cell, and the requirements for the linac will be presented

  1. Accelerating the life of transistors

    Science.gov (United States)

    Haochun, Qi; Changzhi, Lü; Xiaoling, Zhang; Xuesong, Xie

    2013-06-01

    Choosing small and medium power switching transistors of the NPN type in a 3DK set as the study object, the test of accelerating life is conducted in constant temperature and humidity, and then the data are statistically analyzed with software developed by ourselves. According to degradations of such sensitive parameters as the reverse leakage current of transistors, the lifetime order of transistors is about more than 104 at 100 °C and 100% relative humidity (RH) conditions. By corrosion fracture of transistor outer leads and other failure modes, with the failure truncated testing, the average lifetime rank of transistors in different distributions is extrapolated about 103. Failure mechanism analyses of degradation of electrical parameters, outer lead fracture and other reasons that affect transistor lifetime are conducted. The findings show that the impact of external stress of outer leads on transistor reliability is more serious than that of parameter degradation.

  2. Testing general relativity on accelerators

    CERN Document Server

    Kalaydzhyan, Tigran

    2015-01-01

    Within the general theory of relativity, the curvature of spacetime is related to the energy and momentum of the present matter and radiation. One of the more specific predictions of general relativity is the deflection of light and particle trajectories in the gravitational field of massive objects. Bending angles for electromagnetic waves and light in particular were measured with a high precision. However, the effect of gravity on relativistic massive particles was never studied experimentally. Here we propose and analyse experiments devoted to that purpose. We demonstrate a high sensitivity of the laser Compton scattering at high energy accelerators to the effects of gravity. The main observable -- maximal energy of the scattered photons -- would experience a significant shift in the Earth's gravitational field even for otherwise negligible violation of the equivalence principle. We confirm predictions of general relativity for ultrarelativistic electrons of energy of tens of GeV at a current level of res...

  3. Embryonic development during chronic acceleration

    Science.gov (United States)

    Smith, A. H.; Abbott, U. K.

    1982-01-01

    Experiments carried out on chicken eggs indicate that the embryo is affected during very early development, especially over the first four days, and during hatching. In the first four days, the brain develops as well as the anlage for all other organs. In addition, the heart commences to function and the extraembryonic membranes that compartmentalize the egg contents form. The latter require an appreciable extension and folding of tissue which may be disrupted by the mechanical load. Observations of embryonic abnormalities that occur during chronic acceleration suggest an inhibition of development of the axial skeleton, which is rarely seen otherwise, a general retardation of embryonic growth, and circulatory problems. The final stages of development (after 18 days) involve the uptake of fluids, the transition to aerial respiration, and the reorientation of the embryo into a normal hatching position. At 4 G mortality is very high during this period, with a majority of embryos failing to reorient into the normal hatching position.

  4. Development project of small accelerator

    CERN Document Server

    Yamada, S

    2002-01-01

    The object of this project is demonstration of a small proton and heavy ion synchrotron and a small hard X-ray photon radiation source by using new technology and application of them to therapy, diagnosis, material science and life science. In this paper, a part of small proton and heavy ion synchrotron is discussed. Nine organizations joined in this project. There are four development themes such as optimization of laser-ion 100 TW class source target, beam storage and cooling device, small synchrotron ring and FFAG accelerator. Outline and contents of development of them are explained. This project is planning to generate a few MeV/u carbon ions in fully ionized states by impact of laser with about 100 TW output. 3 T maximum bending magnetic field using normal conduction AC magnet will be actualized for synchrotron with 200 MeV proton beam. (S.Y.)

  5. INDIRECT ACCELERATED ADAPTIVE FUZZY CONTROLLER

    Institute of Scientific and Technical Information of China (English)

    ZHU Liye; FANG Yuan; ZHANG Weidong

    2008-01-01

    According to a type of normal nonlinear system, an indirect adaptive fuzzy (IAF) controller has been applied to those systems where no accurate mathematical models of the systems under control are available. To satisfy with system performance, an indirect accelerated adaptive fuzzy (IAAF) controller is proposed, and its general form is presented. The general form IAAF controller ensures necessary control criteria and system's global stability using Lyapunov Theorem. It has been proved that the close-loop system error converges to a small neighborhood of equilibrium point. The optimal IAAF controller is derived to guarantee the process's shortest settling time. Simulation results indicate the IAAF controller make the system more stable, accurate, and fast.

  6. Accelerated Characterization of Polymer Properties

    Energy Technology Data Exchange (ETDEWEB)

    R. Wroczynski; l. Brewer; D. Buckley; M. Burrell; R. Potyrailo

    2003-07-30

    This report describes the efforts to develop a suite of microanalysis techniques that can rapidly measure a variety of polymer properties of industrial importance, including thermal, photo-oxidative, and color stability; as well as ductility, viscosity, and mechanical and antistatic properties. Additional goals of the project were to direct the development of these techniques toward simultaneous measurements of multiple polymer samples of small size in real time using non-destructive and/or parallel or rapid sequential measurements, to develop microcompounding techniques for preparing polymers with additives, and to demonstrate that samples prepared in the microcompounder could be analyzed directly or used in rapid off-line measurements. These enabling technologies are the crucial precursors to the development of high-throughput screening (HTS) methodologies for the polymer additives industry whereby the rate of development of new additives and polymer formulations can be greatly accelerated.

  7. Neuroscience and Accelerator Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Palmblad, M N; Buchholz, B A; Hillegonds, D J; Vogel, J S

    2004-08-02

    Accelerator mass spectrometry (AMS) is a mass spectrometric method for quantifying rare isotopes. It has had great impact in geochronology and archaeology and is now being applied in biomedicine. AMS measures radioisotopes such as {sup 3}H, {sup 14}C, {sup 26}Al, {sup 36}Cl and {sup 41}Ca, with zepto- or attomole sensitivity and high precision and throughput, enabling safe human pharmacokinetic studies involving: microgram doses, agents having low bioavailability, or toxicology studies where administered doses must be kept low (<1 {micro}g/kg). It is used to study long-term pharmacokinetics, to identify biomolecular interactions, to determine chronic and low-dose effects or molecular targets of neurotoxic substances, to quantify transport across the blood-brain barrier and to resolve molecular turnover rates in the human brain on the timescale of decades. We will here review how AMS is applied in neurotoxicology and neuroscience.

  8. Database automation of accelerator operation

    International Nuclear Information System (INIS)

    Database management techniques are applied to automating the setup of operating parameters of a heavy-ion accelerator used in nuclear physics experiments. Data files consist of ion-beam attributes, the interconnection assignments of the numerous power supplies and magnetic elements that steer the ions' path through the system, the data values that represent the electrical currents supplied by the power supplies, as well as the positions of motors and status of mechanical actuators. The database is relational and permits searching on ranges of any subset of the ion-beam attributes. A file selected from the database is used by the control software to replicate the ion beam conditions by adjusting the physical elements in a continuous manner

  9. Extinction Events Can Accelerate Evolution

    DEFF Research Database (Denmark)

    Lehman, Joel; Miikkulainen, Risto

    2015-01-01

    Extinction events impact the trajectory of biological evolution significantly. They are often viewed as upheavals to the evolutionary process. In contrast, this paper supports the hypothesis that although they are unpredictably destructive, extinction events may in the long term accelerate...... evolution by increasing evolvability. In particular, if extinction events extinguish indiscriminately many ways of life, indirectly they may select for the ability to expand rapidly through vacated niches. Lineages with such an ability are more likely to persist through multiple extinctions. Lending...... computational support for this hypothesis, this paper shows how increased evolvability will result from simulated extinction events in two computational models of evolved behavior. The conclusion is that although they are destructive in the short term, extinction events may make evolution more prolific...

  10. Falsifying Paradigms for Cosmic Acceleration

    CERN Document Server

    Mortonson, Michael J; Huterer, Dragan

    2008-01-01

    Consistency relations between growth of structure and expansion history observables exist for any physical explanation of cosmic acceleration, be it a cosmological constant, scalar field quintessence, or a general component of dark energy that is smooth relative to dark matter on small scales. The high-quality supernova sample anticipated from an experiment like SNAP and CMB data expected from Planck thus make strong predictions for growth and expansion observables that additional observations can test and potentially falsify. We perform an MCMC likelihood exploration of the strength of these consistency relations based on a complete parametrization of dark energy behavior by principal components. For LCDM, future SN and CMB data make percent level predictions for growth and expansion observables. For quintessence, many of the predictions are still at a level of a few percent with most of the additional freedom coming from curvature and early dark energy. While such freedom is limited for quintessence where p...

  11. Theoretical Aspects of Cosmic Acceleration

    CERN Document Server

    Trodden, Mark

    2016-01-01

    Efforts to understand and map the possible explanations for the late time acceleration of the universe have led to a broad range of suggestions, ranging from the cosmological constant and straightforward dark energy, to exotically coupled models, to infrared modifications of General Relativity. If we are to uncover which, if any, of these approaches might provide a serious answer to the problem, it is crucial to understand the constraints that theoretical consistency places on the models, and on the regimes in which they make predictions. In this talk, delivered as an invited plenary lecture at the Dark Side of the Universe conference in Kyoto, Japan, I briefly describe some modern attempts to carry out this program and some of the more interesting ideas that have emerged. As an example, I use the Galileon model, discussing how the Vainshtein mechanism occurs, and how a number of these theoretical problems arise around such backgrounds.

  12. Accelerating pulsar timing data analysis

    CERN Document Server

    van Haasteren, Rutger

    2012-01-01

    The analysis of pulsar timing data, especially in pulsar timing array (PTA) projects, has encountered practical difficulties: evaluating the likelihood and/or correlation-based statistics can become prohibitively computationally expensive for large datasets. In situations where a stochastic signal of interest has a power spectral density that dominates the noise in a limited bandwidth of the total frequency domain (e.g. the isotropic background of gravitational waves), a linear transformation exists that transforms the timing residuals to a basis in which virtually all the information about the stochastic signal of interest is contained in a small fraction of basis vectors. By only considering such a small subset of these "generalised residuals", the dimensionality of the data analysis problem is greatly reduced, which can cause a large speedup in the evaluation of the likelihood: the ABC-method (Acceleration By Compression). The compression fidelity, calculable with crude estimates of the signal and noise, c...

  13. Stephen Myers - More collaboration for accelerators

    CERN Multimedia

    2009-01-01

    Stephen Myers has been appointed Director of Accelerators and Technology. His highest priority is to get the LHC running this year, but beyond that he also has the difficult task of balancing resources between non-LHC physics, new projects and consolidation of the existing accelerators. Stephen Myers, previous head of the Accelerator and Beams (AB) Department, will now oversee all the accelerator and technology activities at CERN, including the Beams, Technology and Engineering departments, in the re-established position of Director of Accelerators and Technology. "There are several good reasons to have a single person responsible for the CERN accelerators and technology," said Myers. "Most importantly, this will allow closer collaboration between the three departments and provide the structure for possible redeployment of resources. There will, of course, be regular meetings between the heads of department and myself, and if proble...

  14. Visions for the future of particle accelerators

    Science.gov (United States)

    Romaniuk, Ryszard S.

    2013-10-01

    The ambitions of accelerator based science, technology and applications far exceed the present accelerator possibilities. Accelerator science and technology is one of a key enablers of the developments in the particle physic, photon physics and also applications in medicine and industry. The paper presents a digest of the research results and visions for the future in the domain of accelerator science and technology in Europe, shown during the final fourth annual meeting of the EuCARD - European Coordination of Accelerator Research and Development. The conference concerns building of the research infrastructure, including advanced photonic and electronic systems for servicing large high energy physics experiments. There are debated a few basic groups of such systems like: measurement - control networks of large geometrical extent, multichannel systems for large amounts of metrological data acquisition, precision photonic networks of reference time, frequency and phase distribution. The main subject is however the vision for the future of particle accelerators and next generation light sources.

  15. History of the electrostatic accelerator in Japan

    International Nuclear Information System (INIS)

    Modern Van de Graaff accelerator was first built at Wisconsin University in 1934. After the World War II, High Voltage Engineering Corp. (HVEC) was established and manufactured many Van de Graaff accelerators. The HVEC succeeded in fabricating a Van de Graaff accelerator of tandem type, by which the proton bean with an energy of 20 MeV became available. In 1965 Pelletron was put into practical use. In Japan, development of Van de Graaff accelerator was initiated in 1940's at IPCR, the University of Tokyo, Osaka University, Kyoto University and Kyushu University. After the War, many Van de Graaff accelerators have been supplied mainly from industries. Physicists at Kyushu University developed the accelerator by their own way. (K.Y.)

  16. CAS course on Plasma Wake Acceleration

    CERN Multimedia

    CERN Accelerator School

    2015-01-01

    The CERN Accelerator School (CAS) recently organised a specialised course on Plasma Wake Acceleration, held at CERN, Geneva, Switzerland, from 23 to 29 November 2014.    Following a number of introductory lectures on laser and plasma physics, as well as an overview of conventional accelerators and their limitations, the course covered a large number of aspects of plasma wake acceleration schemes: the creation of plasma by high power lasers or particle beams, a description of the plasma creation process through simulations and the characteristics of the accelerated particle beams, including results of the latest achievements. Lectures on beam diagnostics, the applications of plasma accelerated beams, and topical seminars completed the programme.  The course was very successful, with 109 students of 26 nationalities attending; most participants coming from European counties, but also from the US, Israel, India, South Korea, Russia and Ukraine. Feedback from the participants was...

  17. Nonresonant Grain Acceleration in MHD Turbulence

    CERN Document Server

    Yan, Huirong

    2009-01-01

    We discuss a new type of dust acceleration mechanism that acts in a turbulent magnetized medium. The magnetohydrodynamic (MHD) turbulence can accelerate grains through resonant as well as nonresonant interactions. We show that the magnetic compression provides higher velocities for super-Alfv\\'enic turbulence and can accelerate an extended range of grains in warm media compared to gyroresonance. While fast modes dominate the acceleration for the large grains, slow modes can be important for sub-micron grains. We provide comprehensive discussion of all the possible grain acceleration mechanisms in interstellar medium. We show that supersonic velocities are attainable for Galactic dust grains. We discuss the consequence of the acceleration. The implications for extinction curve, grain alignment, chemical abundance, etc, are provided.

  18. Development of S-band accelerating structure

    International Nuclear Information System (INIS)

    In Pohang Accelerator Laboratory (PAL) in Korea construction of XFEL (X-ray Free electron Lazar) institution is under construction aiming at the completion in 2014. Energy 10 GeV of the linac part of this institution and main frequency are planned in S-band (2856 MHz), and about 178 S-band 3m accelerating structures are due to be used for this linac. The oscillation of an X-ray laser requires very low emittance electron beam. On the other hand, since the accelerating structure which accelerates an electron beam has a feed port of microwave (iris), the electromagnetic field asymmetry of the microwave feeding device called coupler worsens the emittance of an electron beam. MHI manufactured two kinds of S-band accelerating structures with which the electromagnetic field asymmetry of coupler cavity was compensated for PALXFEL linac. We report these accelerating structures. (author)

  19. Elements of a dielectric laser accelerator

    CERN Document Server

    McNeur, Joshua; Schönenberger, Norbert; Leedle, Kenneth J; Deng, Huiyang; Ceballos, Andrew; Hoogland, Heinar; Ruehl, Axel; Hartl, Ingmar; Solgaard, Olav; Harris, James S; Byer, Robert L; Hommelhoff, Peter

    2016-01-01

    The widespread use of high energy particle beams in basic research, medicine and coherent X-ray generation coupled with the large size of modern radio frequency (RF) accelerator devices and facilities has motivated a strong need for alternative accelerators operating in regimes outside of RF. Working at optical frequencies, dielectric laser accelerators (DLAs) - transparent laser-driven nanoscale dielectric structures whose near fields can synchronously accelerate charged particles - have demonstrated high-gradient acceleration with a variety of laser wavelengths, materials, and electron beam parameters, potentially enabling miniaturized accelerators and table-top coherent x-ray sources. To realize a useful (i.e. scalable) DLA, crucial developments have remained: concatenation of components including sustained phase synchronicity to reach arbitrary final energies as well as deflection and focusing elements to keep the beam well collimated along the design axis. Here, all of these elements are demonstrated wit...

  20. High intensity laser-driven ion acceleration

    International Nuclear Information System (INIS)

    Ion acceleration by intense laser-plasma interactions is a very active field of research whose development can be traced in a large number of publications over the last few years. Past studies were mostly performed irradiating thin foils where protons are predominantly accelerated to energies up to 60 MeV in an exponentially decaying spectrum by a mechanism named target normal sheath acceleration (TNSA). We present our latest experimental advances on acceleration schemes away from TNSA, such as shock acceleration, ion beam generation from relativistically transparent targets and radiation-pressure acceleration. These results are a major step towards highly energetic, mono-chromatic ion beams generated at high conversion efficiencies as demanded by many potential applications. Those include fast ignition inertial confinement fusion (ICF) as well as oncology and radiation therapy of tumors.

  1. Accelerating cleanup: Paths to closure

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-06-01

    This report describes the status of Environmental Management`s (EM`s) cleanup program and a direction forward to complete achievement of the 2006 vision. Achieving the 2006 vision results in significant benefits related to accomplishing EM program objectives. As DOE sites accelerate cleanup activities, risks to public health, the environment, and worker safety and health are all reduced. Finding more efficient ways to conduct work can result in making compliance with applicable environmental requirements easier to achieve. Finally, as cleanup activities at sites are completed, the EM program can focus attention and resources on the small number of sites with more complex cleanup challenges. Chapter 1 describes the process by which this report has been developed and what it hopes to accomplish, its relationship to the EM decision-making process, and a general background of the EM mission and program. Chapter 2 describes how the site-by-site projections were constructed, and summarizes, for each of DOE`s 11 Operations/Field Offices, the projected costs and schedules for completing the cleanup mission. Chapter 3 presents summaries of the detailed cleanup projections from three of the 11 Operations/Field Offices: Rocky Flats (Colorado), Richland (Washington), and Savannah River (South Carolina). The remaining eight Operations/Field Office summaries are in Appendix E. Chapter 4 reviews the cost drivers, budgetary constraints, and performance enhancements underlying the detailed analysis of the 353 projects that comprise EM`s accelerated cleanup and closure effort. Chapter 5 describes a management system to support the EM program. Chapter 6 provides responses to the general comments received on the February draft of this document.

  2. Accelerating cleanup: Paths to closure

    International Nuclear Information System (INIS)

    This report describes the status of Environmental Management's (EM's) cleanup program and a direction forward to complete achievement of the 2006 vision. Achieving the 2006 vision results in significant benefits related to accomplishing EM program objectives. As DOE sites accelerate cleanup activities, risks to public health, the environment, and worker safety and health are all reduced. Finding more efficient ways to conduct work can result in making compliance with applicable environmental requirements easier to achieve. Finally, as cleanup activities at sites are completed, the EM program can focus attention and resources on the small number of sites with more complex cleanup challenges. Chapter 1 describes the process by which this report has been developed and what it hopes to accomplish, its relationship to the EM decision-making process, and a general background of the EM mission and program. Chapter 2 describes how the site-by-site projections were constructed, and summarizes, for each of DOE's 11 Operations/Field Offices, the projected costs and schedules for completing the cleanup mission. Chapter 3 presents summaries of the detailed cleanup projections from three of the 11 Operations/Field Offices: Rocky Flats (Colorado), Richland (Washington), and Savannah River (South Carolina). The remaining eight Operations/Field Office summaries are in Appendix E. Chapter 4 reviews the cost drivers, budgetary constraints, and performance enhancements underlying the detailed analysis of the 353 projects that comprise EM's accelerated cleanup and closure effort. Chapter 5 describes a management system to support the EM program. Chapter 6 provides responses to the general comments received on the February draft of this document

  3. Report on accelerated corrosion studies.

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-03-01

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

  4. Accelerator Technology Division progress report, FY 1993

    International Nuclear Information System (INIS)

    This report discusses the following topics: A Next-Generation Spallation-Neutron Source; Accelerator Performance Demonstration Facility; APEX Free-Electron Laser Project; The Ground Test Accelerator (GTA) Program; Intense Neutron Source for Materials Testing; Linac Physics and Special Projects; Magnetic Optics and Beam Diagnostics; Radio-Frequency Technology; Accelerator Controls and Automation; Very High-Power Microwave Sources and Effects; and GTA Installation, Commissioning, and Operation

  5. Propulsion Through Electromagnetic Self-Sustained Acceleration

    OpenAIRE

    Petkov, Vesselin

    1999-01-01

    As is known the repulsion of the volume elements of an uniformly accelerating charge or a charge supported in an uniform gravitational field accounts for the electromagnetic contribution to the charge's inertial and gravitational mass, respectively. This means that the mutual repulsion of the volume elements of the charge produces the resistance to its accelerated motion. Conversely, the effect of electromagnetic attraction of opposite charges enhances the accelerated motion of the charges pr...

  6. The transfer of accelerator technology to industry

    International Nuclear Information System (INIS)

    The national laboratories and universities are sources for innovative accelerator technology developments. With the growing application of accelerators in such fields as semiconductor manufacturing, medical therapy isotope production, nuclear waste transmutation, materials testing, bomb detection, pure science, etc., it is becoming more important to transfer these technologies and build an accelerator industrial base. In this talk the methods of technology transfer, the issues involved in working with the labs and examples of successful technology transfers are discussed. (Author)

  7. The Los Alamos accelerator code group

    International Nuclear Information System (INIS)

    The Los Alamos Accelerator Code Group (LAACG) is a national resource for members of the accelerator community who use and/or develop software for the design and analysis of particle accelerators, beam transport systems, light sources, storage rings, and components of these systems. Below the authors describe the LAACG's activities in high performance computing, maintenance and enhancement of POISSON/SUPERFISH and related codes and the dissemination of information on the INTERNET

  8. Tidal acceleration of black holes and superradiance

    OpenAIRE

    Cardoso, Vitor; Pani, Paolo

    2012-01-01

    Tidal effects have long ago locked the Moon in synchronous rotation with the Earth and progressively increase the Earth-Moon distance. This "tidal acceleration" hinges on dissipation. Binaries containing black holes may also be tidally accelerated, dissipation being caused by the event horizon - a flexible, viscous one-way membrane. In fact, this process is known for many years under a different guise: superradiance. In General Relativity, tidal acceleration is obscured by gravitational-wave ...

  9. Unifying physics of accelerators, lasers and plasma

    CERN Document Server

    Seryi, Andrei

    2015-01-01

    Unifying Physics of Accelerators, Lasers and Plasma introduces the physics of accelerators, lasers and plasma in tandem with the industrial methodology of inventiveness, a technique that teaches that similar problems and solutions appear again and again in seemingly dissimilar disciplines. This unique approach builds bridges and enhances connections between the three aforementioned areas of physics that are essential for developing the next generation of accelerators.

  10. Accelerating cosmologies from compactification with a twist

    International Nuclear Information System (INIS)

    It is demonstrated by explicit solutions of the (4+n)-dimensional vacuum Einstein equations that accelerating cosmologies in the Einstein conformal frame can be obtained by a time-dependent compactification of string/M-theory, even in the case that internal dimensions are Ricci-flat, provided one includes one or more geometric twists. Such acceleration is transient. When both compact hyperbolic internal spaces and geometric twists are included, however, the period of accelerated expansion may be made arbitrarily large

  11. Accelerating cosmologies from compactification with a twist

    Energy Technology Data Exchange (ETDEWEB)

    Neupane, Ishwaree P. [Department of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch (New Zealand) and Central Department of Physics, Tribhuvan University, Kirtipur, Kathmandu (Nepal)]. E-mail: ishwaree.neupane@canterbury.ac.nz; Wiltshire, David L. [Central Department of Physics, Tribhuvan University, Kirtipur, Kathmandu (Nepal)]. E-mail: d.wiltshire@canterbury.ac.nz

    2005-07-21

    It is demonstrated by explicit solutions of the (4+n)-dimensional vacuum Einstein equations that accelerating cosmologies in the Einstein conformal frame can be obtained by a time-dependent compactification of string/M-theory, even in the case that internal dimensions are Ricci-flat, provided one includes one or more geometric twists. Such acceleration is transient. When both compact hyperbolic internal spaces and geometric twists are included, however, the period of accelerated expansion may be made arbitrarily large.

  12. Fixed-Field Alternating-Gradient Accelerators

    CERN Document Server

    Sheehy, S L

    2016-01-01

    These notes provide an overview of Fixed-Field Alternating-Gradient (FFAG) accelerators for medical applications. We begin with a review of the basic principles of this type of accelerator, including the scaling and non-scaling types, highlighting beam dynamics issues that are of relevance to hadron ac- celerators. The potential of FFAG accelerators in the field of hadron therapy is discussed in detail, including an overview of existing medical FFAG designs. The options for FFAG treatment gantries are also considered.

  13. Accelerated life models modeling and statistical analysis

    CERN Document Server

    Bagdonavicius, Vilijandas

    2001-01-01

    Failure Time DistributionsIntroductionParametric Classes of Failure Time DistributionsAccelerated Life ModelsIntroductionGeneralized Sedyakin's ModelAccelerated Failure Time ModelProportional Hazards ModelGeneralized Proportional Hazards ModelsGeneralized Additive and Additive-Multiplicative Hazards ModelsChanging Shape and Scale ModelsGeneralizationsModels Including Switch-Up and Cycling EffectsHeredity HypothesisSummaryAccelerated Degradation ModelsIntroductionDegradation ModelsModeling the Influence of Explanatory Varia

  14. Kinematics of transition during human accelerated sprinting

    Directory of Open Access Journals (Sweden)

    Ryu Nagahara

    2014-07-01

    Full Text Available This study investigated kinematics of human accelerated sprinting through 50 m and examined whether there is transition and changes in acceleration strategies during the entire acceleration phase. Twelve male sprinters performed a 60-m sprint, during which step-to-step kinematics were captured using 60 infrared cameras. To detect the transition during the acceleration phase, the mean height of the whole-body centre of gravity (CG during the support phase was adopted as a measure. Detection methods found two transitions during the entire acceleration phase of maximal sprinting, and the acceleration phase could thus be divided into initial, middle, and final sections. Discriminable kinematic changes were found when the sprinters crossed the detected first transition—the foot contacting the ground in front of the CG, the knee-joint starting to flex during the support phase, terminating an increase in step frequency—and second transition—the termination of changes in body postures and the start of a slight decrease in the intensity of hip-joint movements, thus validating the employed methods. In each acceleration section, different contributions of lower-extremity segments to increase in the CG forward velocity—thigh and shank for the initial section, thigh, shank, and foot for the middle section, shank and foot for the final section—were verified, establishing different acceleration strategies during the entire acceleration phase. In conclusion, there are presumably two transitions during human maximal accelerated sprinting that divide the entire acceleration phase into three sections, and different acceleration strategies represented by the contributions of the segments for running speed are employed.

  15. An Accelerator Control Middle Layer Using MATLAB

    OpenAIRE

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

    2005-01-01

    Matlab is a matrix manipulation language originally developed to be a convenient language for using the LINPACK and EISPACK libraries. What makes Matlab so appealing for accelerator physics is the combination of a matrix oriented programming language, an active workspace for system variables, powerful graphics capability, built-in math libraries, and platform independence. A number of software toolboxes for accelerators have been written in Matlab -- the Accelerator Toolbox (AT) for mach...

  16. Acceleration of Astrophysical Simulations with Special Hardware

    OpenAIRE

    Marcus Martinez, Guillermo Anibal

    2011-01-01

    This work presents the raceSPH and raceGRAV accelerator libraries, designed to interface astrophysical simulations with special-purpose hardware. The raceSPH focuses on the acceleration of Smoothed Particle Hydrodynamics (SPH), a method for approximating force interactions in fluid dynamics. Accelerators used range from vectorizing units on the microprocessors to Field Programmable Gate Arrays (FPGAs) and Graphics Processing Units (GPUs), and speed-ups range from 1.2x to 28x when measured in ...

  17. Pulse Power Supply for Plasma Dynamic Accelerator

    Institute of Scientific and Technical Information of China (English)

    YANG Xuanzong; LIU Jian; FENG Chunhua; WANG Long

    2008-01-01

    A new concept of a coaxial plasma dynamic accelerator with a self-energized mag-netic compressor coil to simulate the effects of space debris impact is demonstrated. A brief description is presented about the pulse power supply system including the charging circuit, start switch and current transfer system along with some of the key techniques for this kind of acceler-ator. Using this accelerator configuration, ceramic beads of 100 μm in diameter were accelerated to a speed as high as 18 km/sec. The facility can be used in a laboratory setting to study impact phenomena on solar array materials, potential structural materials for use in space.

  18. New accelerators in high-energy physics

    International Nuclear Information System (INIS)

    First, I should like to mention a few new ideas that have appeared during the last few years in the accelerator field. A couple are of importance in the design of injectors, usually linear accelerators, for high-energy machines. Then I shall review some of the somewhat sensational accelerator projects, now in operation, under construction or just being proposed. Finally, I propose to mention a few applications of high-energy accelerators in fields other than high-energy physics. I realize that this is a digression from my title but I hope that you will find it interesting

  19. Research on feedback system of synchrotron accelerator

    International Nuclear Information System (INIS)

    It is a very complex problem to use feedback control system in synchrotron accelerator. Some scientists design feedback control system to make high energy beam stable in synchrotron accelerator, but it is very rare to see theoretically analysis feedback system in synchrotron accelerator by using new concept of control model. One new feedback control model is a fresh idea to discuss the feedback system more deeply. A topic about feedback control system discussed here will be useful for synchrotron accelerator design and operation. It is an good idea for some scientists and technician to continue study. (authors)

  20. Future HEP Accelerators: The US Perspective

    Energy Technology Data Exchange (ETDEWEB)

    Bhat, Pushpalatha [Fermilab; Shiltsev, Vladimir [Fermilab

    2015-11-02

    Accelerator technology has advanced tremendously since the introduction of accelerators in the 1930s, and particle accelerators have become indispensable instruments in high energy physics (HEP) research to probe Nature at smaller and smaller distances. At present, accelerator facilities can be classified into Energy Frontier colliders that enable direct discoveries and studies of high mass scale particles and Intensity Frontier accelerators for exploration of extremely rare processes, usually at relatively low energies. The near term strategies of the global energy frontier particle physics community are centered on fully exploiting the physics potential of the Large Hadron Collider (LHC) at CERN through its high-luminosity upgrade (HL-LHC), while the intensity frontier HEP research is focused on studies of neutrinos at the MW-scale beam power accelerator facilities, such as Fermilab Main Injector with the planned PIP-II SRF linac project. A number of next generation accelerator facilities have been proposed and are currently under consideration for the medium- and long-term future programs of accelerator-based HEP research. In this paper, we briefly review the post-LHC energy frontier options, both for lepton and hadron colliders in various regions of the world, as well as possible future intensity frontier accelerator facilities.

  1. 2nd European Advanced Accelerator Concepts Workshop

    CERN Document Server

    Assmann, Ralph; Grebenyuk, Julia

    2016-01-01

    The European Advanced Accelerator Concepts Workshop has the mission to discuss and foster methods of beam acceleration with gradients beyond state of the art in operational facilities. The most cost effective and compact methods for generating high energy particle beams shall be reviewed and assessed. This includes diagnostics methods, timing technology, special need for injectors, beam matching, beam dynamics with advanced accelerators and development of adequate simulations. This workshop is organized in the context of the EU-funded European Network for Novel Accelerators (EuroNNAc2), that includes 52 Research Institutes and universities.

  2. 17 GHz High Gradient Accelerator Research

    Energy Technology Data Exchange (ETDEWEB)

    Temkin, Richard J. [MIT; Shapiro, Michael A. [MIT

    2013-07-10

    This is a report on the MIT High Gradient Accelerator Research program which has included: Operation of the 17 GHz, 25 MeV MIT/Haimson Research Corp. electron accelerator at MIT, the highest frequency, stand-alone accelerator in the world; collaboration with members of the US High Gradient Collaboration, including the design and test of novel structures at SLAC at 11.4 GHz; the design, construction and testing of photonic bandgap structures, including metallic and dielectric structures; the investigation of the wakefields in novel structures; and the training of the next generation of graduate students and postdoctoral associates in accelerator physics.

  3. The Spallation Neutron Source accelerator system design

    Science.gov (United States)

    Henderson, S.; Abraham, W.; Aleksandrov, A.; Allen, C.; Alonso, J.; Anderson, D.; Arenius, D.; Arthur, T.; Assadi, S.; Ayers, J.; Bach, P.; Badea, V.; Battle, R.; Beebe-Wang, J.; Bergmann, B.; Bernardin, J.; Bhatia, T.; Billen, J.; Birke, T.; Bjorklund, E.; Blaskiewicz, M.; Blind, B.; Blokland, W.; Bookwalter, V.; Borovina, D.; Bowling, S.; Bradley, J.; Brantley, C.; Brennan, J.; Brodowski, J.; Brown, S.; Brown, R.; Bruce, D.; Bultman, N.; Cameron, P.; Campisi, I.; Casagrande, F.; Catalan-Lasheras, N.; Champion, M.; Champion, M.; Chen, Z.; Cheng, D.; Cho, Y.; Christensen, K.; Chu, C.; Cleaves, J.; Connolly, R.; Cote, T.; Cousineau, S.; Crandall, K.; Creel, J.; Crofford, M.; Cull, P.; Cutler, R.; Dabney, R.; Dalesio, L.; Daly, E.; Damm, R.; Danilov, V.; Davino, D.; Davis, K.; Dawson, C.; Day, L.; Deibele, C.; Delayen, J.; DeLong, J.; Demello, A.; DeVan, W.; Digennaro, R.; Dixon, K.; Dodson, G.; Doleans, M.; Doolittle, L.; Doss, J.; Drury, M.; Elliot, T.; Ellis, S.; Error, J.; Fazekas, J.; Fedotov, A.; Feng, P.; Fischer, J.; Fox, W.; Fuja, R.; Funk, W.; Galambos, J.; Ganni, V.; Garnett, R.; Geng, X.; Gentzlinger, R.; Giannella, M.; Gibson, P.; Gillis, R.; Gioia, J.; Gordon, J.; Gough, R.; Greer, J.; Gregory, W.; Gribble, R.; Grice, W.; Gurd, D.; Gurd, P.; Guthrie, A.; Hahn, H.; Hardek, T.; Hardekopf, R.; Harrison, J.; Hatfield, D.; He, P.; Hechler, M.; Heistermann, F.; Helus, S.; Hiatt, T.; Hicks, S.; Hill, J.; Hill, J.; Hoff, L.; Hoff, M.; Hogan, J.; Holding, M.; Holik, P.; Holmes, J.; Holtkamp, N.; Hovater, C.; Howell, M.; Hseuh, H.; Huhn, A.; Hunter, T.; Ilg, T.; Jackson, J.; Jain, A.; Jason, A.; Jeon, D.; Johnson, G.; Jones, A.; Joseph, S.; Justice, A.; Kang, Y.; Kasemir, K.; Keller, R.; Kersevan, R.; Kerstiens, D.; Kesselman, M.; Kim, S.; Kneisel, P.; Kravchuk, L.; Kuneli, T.; Kurennoy, S.; Kustom, R.; Kwon, S.; Ladd, P.; Lambiase, R.; Lee, Y. Y.; Leitner, M.; Leung, K.-N.; Lewis, S.; Liaw, C.; Lionberger, C.; Lo, C. C.; Long, C.; Ludewig, H.; Ludvig, J.; Luft, P.; Lynch, M.; Ma, H.; MacGill, R.; Macha, K.; Madre, B.; Mahler, G.; Mahoney, K.; Maines, J.; Mammosser, J.; Mann, T.; Marneris, I.; Marroquin, P.; Martineau, R.; Matsumoto, K.; McCarthy, M.; McChesney, C.; McGahern, W.; McGehee, P.; Meng, W.; Merz, B.; Meyer, R.; Meyer, R.; Miller, B.; Mitchell, R.; Mize, J.; Monroy, M.; Munro, J.; Murdoch, G.; Musson, J.; Nath, S.; Nelson, R.; Nelson, R.; O`Hara, J.; Olsen, D.; Oren, W.; Oshatz, D.; Owens, T.; Pai, C.; Papaphilippou, I.; Patterson, N.; Patterson, J.; Pearson, C.; Pelaia, T.; Pieck, M.; Piller, C.; Plawski, T.; Plum, M.; Pogge, J.; Power, J.; Powers, T.; Preble, J.; Prokop, M.; Pruyn, J.; Purcell, D.; Rank, J.; Raparia, D.; Ratti, A.; Reass, W.; Reece, K.; Rees, D.; Regan, A.; Regis, M.; Reijonen, J.; Rej, D.; Richards, D.; Richied, D.; Rode, C.; Rodriguez, W.; Rodriguez, M.; Rohlev, A.; Rose, C.; Roseberry, T.; Rowton, L.; Roybal, W.; Rust, K.; Salazer, G.; Sandberg, J.; Saunders, J.; Schenkel, T.; Schneider, W.; Schrage, D.; Schubert, J.; Severino, F.; Shafer, R.; Shea, T.; Shishlo, A.; Shoaee, H.; Sibley, C.; Sims, J.; Smee, S.; Smith, J.; Smith, K.; Spitz, R.; Staples, J.; Stein, P.; Stettler, M.; Stirbet, M.; Stockli, M.; Stone, W.; Stout, D.; Stovall, J.; Strelo, W.; Strong, H.; Sundelin, R.; Syversrud, D.; Szajbler, M.; Takeda, H.; Tallerico, P.; Tang, J.; Tanke, E.; Tepikian, S.; Thomae, R.; Thompson, D.; Thomson, D.; Thuot, M.; Treml, C.; Tsoupas, N.; Tuozzolo, J.; Tuzel, W.; Vassioutchenko, A.; Virostek, S.; Wallig, J.; Wanderer, P.; Wang, Y.; Wang, J. G.; Wangler, T.; Warren, D.; Wei, J.; Weiss, D.; Welton, R.; Weng, J.; Weng, W.-T.; Wezensky, M.; White, M.; Whitlatch, T.; Williams, D.; Williams, E.; Wilson, K.; Wiseman, M.; Wood, R.; Wright, P.; Wu, A.; Ybarrolaza, N.; Young, K.; Young, L.; Yourd, R.; Zachoszcz, A.; Zaltsman, A.; Zhang, S.; Zhang, W.; Zhang, Y.; Zhukov, A.

    2014-11-01

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

  4. Accelerators and superconductivity: A marriage of convenience

    International Nuclear Information System (INIS)

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

  5. STATUS OF THE DIELECTRIC WALL ACCELERATOR

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-04-22

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

  6. Search for Dark Photons with Accelerators

    Directory of Open Access Journals (Sweden)

    Merkel Harald

    2014-01-01

    Full Text Available A dark photon as the mediator of an interaction of the dark sector is a well motivated extension of the standard model. While possible dark matter particles are heavy and seem to be beyond the reach of current accelerators, the dark photon is not necessarily heavy and might have a mass in the range of existing accelerators. In recent years, an extensive experimental program at several accelerators for the search for dark photons were established. In this talk, recent results and progress in the determination of exclusion limits with accelerators is presented.

  7. The Spallation Neutron Source accelerator system design

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, S., E-mail: stuarth@fnal.gov [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831 (United States); Abraham, W. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Aleksandrov, A. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831 (United States); Allen, C. [Techsource, Inc., 1475 Central Avenue, Suite 250, Los Alamos, NM 87544-3291 (United States); Alonso, J. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Anderson, D. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831 (United States); Arenius, D. [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Avenue, Newport News, VA 23606 (United States); Arthur, T. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831 (United States); Assadi, S. [Techsource, Inc., 1475 Central Avenue, Suite 250, Los Alamos, NM 87544-3291 (United States); Ayers, J.; Bach, P. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Badea, V. [Brookhaven National Laboratory, P.O. Box 5000, Upton, NY 11973-5000 (United States); Battle, R. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831 (United States); Beebe-Wang, J. [Brookhaven National Laboratory, P.O. Box 5000, Upton, NY 11973-5000 (United States); Bergmann, B.; Bernardin, J.; Bhatia, T.; Billen, J.; Birke, T.; Bjorklund, E. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States); and others

    2014-11-01

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

  8. Advances of Accelerator Physics and Technologies

    CERN Document Server

    1993-01-01

    This volume, consisting of articles written by experts with international repute and long experience, reviews the state of the art of accelerator physics and technologies and the use of accelerators in research, industry and medicine. It covers a wide range of topics, from basic problems concerning the performance of circular and linear accelerators to technical issues and related fields. Also discussed are recent achievements that are of particular interest (such as RF quadrupole acceleration, ion sources and storage rings) and new technologies (such as superconductivity for magnets and RF ca

  9. Accelerator Center for Energy Research (ACER)

    Data.gov (United States)

    Federal Laboratory Consortium — The Accelerator Center for Energy Research (ACER) exploits radiation chemistry techniques to study chemical reactions (and other phenomena) by subjecting samples to...

  10. Beam dynamics in high energy particle accelerators

    CERN Document Server

    Wolski, Andrzej

    2014-01-01

    Particle accelerators are essential tools for scientific research in fields as diverse as high energy physics, materials science and structural biology. They are also widely used in industry and medicine. Producing the optimum design and achieving the best performance for an accelerator depends on a detailed understanding of many (often complex and sometimes subtle) effects that determine the properties and behavior of the particle beam. Beam Dynamics in High Energy Particle Accelerators provides an introduction to the concepts underlying accelerator beam line design and analysis, taking an approach that emphasizes the elegance of the subject and leads into the development of a range of powerful techniques for understanding and modeling charged particle beams.

  11. VEDs for charged particle accelerators: Indian scenario

    International Nuclear Information System (INIS)

    In the initial times after their invention, the charged particle accelerators have, primarily, been used for fundamental studies on nuclei and atoms. From the first modern accelerator, the cathode ray tube, used by J.J. Thomson for the discovery of electron, very recently the gigantic 27 km circumference Large Hadron Collider (LHC) is operational in the search of Higg's boson and related physics issues. Particle accelerators have emerged as powerful microscopes for investigating the finest details of cells, genes, molecules, atoms, protons, neutrons, muons, electrons, quarks and, possibly, still undiscovered even more fundamental constituents of the universe, such as dark matter and dark energy. Several noble prize winning discoveries have been made using accelerators. Accelerators are now being used in a wide area of industrial and medical applications. They are used for the production of radioisotopes for medical imaging, cancer therapy, food sterilization, treatment of waste water, sterilization of medical equipment, material modification, mass spectroscopy, cargo scanning, fabrication of semiconductors etc. Ongoing effort towards the development of accelerators with megawatt beam power is showing hope for a cleaner source of nuclear energy and treatment of nuclear waste. Several tens of thousands of accelerators are presently operational in the world for basic research and applications. Development of new accelerators has several times been driven by new technologies and materials and sometimes they have driven the technological developments towards cutting edge. Some examples are ultra-high vacuum in large volumes, superfluid helium in cryogenics, cryocoolers, superconducting magnets and RF cavities, high power vacuum electronic devices, global control systems, superfast computing and communication networks, giant data storage/processing systems etc. India has been pursuing a fairly robust programme of accelerator development at various institutions. It

  12. Accelerator physics and technology research toward future multi-MW proton accelerators

    CERN Document Server

    Shiltsev, V; Romanenko, A; Valishev, A; Zwaska, R

    2015-01-01

    Recent P5 report indicated the accelerator-based neutrino and rare decay physics research as a centrepiece of the US domestic HEP program. Operation, upgrade and development of the accelerators for the near-term and longer-term particle physics program at the Intensity Frontier face formidable challenges. Here we discuss accelerator physics and technology research toward future multi-MW proton accelerators.

  13. Application of local area networks to accelerator control systems at the Stanford Linear Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Fox, J.D.; Linstadt, E.; Melen, R.

    1983-03-01

    The history and current status of SLAC's SDLC networks for distributed accelerator control systems are discussed. These local area networks have been used for instrumentation and control of the linear accelerator. Network topologies, protocols, physical links, and logical interconnections are discussed for specific applications in distributed data acquisition and control system, computer networks and accelerator operations.

  14. Application of local area networks to accelerator control systems at the Stanford Linear Accelerator

    International Nuclear Information System (INIS)

    The history and current status of SLAC's SDLC networks for distributed accelerator control systems are discussed. These local area networks have been used for instrumentation and control of the linear accelerator. Network topologies, protocols, physical links, and logical interconnections are discussed for specific applications in distributed data acquisition and control system, computer networks and accelerator operations

  15. Social-emotional characteristics of gifted accelerated and non-accelerated students in the Netherlands

    NARCIS (Netherlands)

    Hoogeveen, A.J.M.; Hell, J.G. van; Verhoeven, L.T.W.

    2012-01-01

    Background. In the studies of acceleration conducted so far a multidimensional perspective has largely been neglected. No attempt has been made to relate social-emotional characteristics of accelerated versus non-accelerated students in perspective of environmental factors. Aims. In this study, soci

  16. Gas breakdown limit and maximum acceleration gradient for inverse Cherenkov laser accelerator

    CERN Document Server

    Liu, Y; Cline, D

    1999-01-01

    Laser intensity thresholds for CO sub 2 laser-induced gas breakdown, such as tunneling, multiphoton, and cascade ionization have been estimated for the inverse Cherenkov accelerator experiment at the Brookhaven Accelerator Test Facility. The gas breakdown is dominated by cascade ionization and the maximum acceleration gradient is up to 300 MeV/m for a 3 ps CO sub 2 laser.

  17. Social-Emotional Characteristics of Gifted Accelerated and Non-Accelerated Students in the Netherlands

    Science.gov (United States)

    Hoogeveen, Lianne; van Hell, Janet G.; Verhoeven, Ludo

    2012-01-01

    Background: In the studies of acceleration conducted so far a multidimensional perspective has largely been neglected. No attempt has been made to relate social-emotional characteristics of accelerated versus non-accelerated students in perspective of environmental factors. Aims: In this study, social-emotional characteristics of accelerated…

  18. A Survey of Hadron Therapy Accelerator Technologies

    International Nuclear Information System (INIS)

    Hadron therapy has entered a new age [1]. The number of facilities grows steadily, and 'consumer' interest is high. Some groups are working on new accelerator technology, while others optimize existing designs by reducing capital and operating costs, and improving performance. This paper surveys the current requirements and directions in accelerator technology for hadron therapy

  19. Measurement of Coriolis Acceleration with a Smartphone

    Science.gov (United States)

    Shaku, Asif; Kraft, Jakob

    2016-01-01

    Undergraduate physics laboratories seldom have experiments that measure the Coriolis acceleration. This has traditionally been the case owing to the inherent complexities of making such measurements. Articles on the experimental determination of the Coriolis acceleration are few and far between in the physics literature. However, because modern…

  20. Acceleration Statistics in Rotating and Sheared Turbulence

    Science.gov (United States)

    Jacobitz, Frank; Schneider, Kai; Bos, Wouter; Farge, Marie

    2012-11-01

    Acceleration statistics are of fundamental interest in turbulence ranging from theoretical questions to modeling of dispersion processes. Direct numerical simulations of sheared and rotating homogeneous turbulence are performed with different ratios of Coriolis parameter to shear rate. The statistics of Lagrangian and Eulerian acceleration are studied with a particular focus on the influence of the rotation ratio and also on the scale dependence of the statistics. The probability density functions (pdfs) of both Lagrangian and Eulerian acceleration show a strong and similar influence on the rotation ratio. The flatness further quantifies its influence and yields values close to three for strong rotation. For moderate and vanishing rotation, the flatness of the Eulerian acceleration is larger than that of the Lagrangian acceleration, contrary to previous results for isotropic turbulence. A wavelet-based scale-dependent analysis shows that the flatness of both Eulerian and Lagrangian acceleration increases as scale decreases. For strong rotation, the Eulerian acceleration is more intermittent than the Lagrangian acceleration, while the opposite result is obtained for moderate rotation.

  1. Possible instabilities in the beat wave accelerator

    International Nuclear Information System (INIS)

    In this article the concept of the beat wave accelerator is studied with emphasis put on the plasma physics. An important effect is the relativistic nature of the electrons oscillating in the electric field of the beat wave. Various instabilities are presented which could limit the overall efficiency of the accelerating process. (author)

  2. Accelerator physics issues at the SSC

    Energy Technology Data Exchange (ETDEWEB)

    Dugan, G.F.

    1993-05-01

    Realization of the design energy and luminosity goals of the Superconducting Super Collider (SSC) will require proper resolutions of a number of challenging problems in accelerator physics. The status of several salient issues in the design of the SSC will be reviewed and updated in this paper. The emphasis will be on the superconducting accelerators.

  3. Accelerator research studies: Annual technical report

    International Nuclear Information System (INIS)

    This paper discusses accelerator research at the University of Maryland. The three task studies contained in this paper are: Instabilities and Emittance Growth in Periodic Focusing Systems for Intense Beams; Collective Ion Acceleration by Intense Electron Beams and Pulse Powered Plasma Focus; and Microwave Sources and Parameter Scaling for High-Frequency e+e/sup /minus// Supercollider Linacs

  4. New accelerators. Why do we need them?

    International Nuclear Information System (INIS)

    The impressive success of the Standard Model of quarks and leptons and their unified interactions has stimulated new and important questions for both nuclear and particle physics. These questions have motivated the planning and construction of several large new accelerator facilities with complementary science programs. We touch here on some of the physics goals that will be pursued with the new breed of accelerators

  5. 20 years PSI accelerator. The speeches

    International Nuclear Information System (INIS)

    This publication contains the text of four papers presented at the occasion of the 20 year Symposium of the PSI accelerator. The papers dealt with the following topics: Scientific research and its dual interaction with industry and with the general public, the history of the PSI accelerator, μ-n-γ investigations on high temperature superconductors, therapy with charged particles. figs., tabs., refs

  6. 5 CFR 179.308 - Accelerated procedures.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Accelerated procedures. 179.308 Section 179.308 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS CLAIMS COLLECTION STANDARDS Administrative Offset § 179.308 Accelerated procedures. OPM may make an...

  7. Research of Virtual Accelerator Control System

    Institute of Scientific and Technical Information of China (English)

    DongJinmei; YuanYoujin; ZhengJianhua

    2003-01-01

    A Virtual Accelerator is a computer process which simulates behavior of beam in an accelerator and responds to the accelerator control program under development in a same way as an actual accelerator. To realize Virtual Accelerator, control system should provide the same program interface to top layer Application Control Program, it can make 'Real Accelerator' and 'Virtual Accelerator'use the same GUI, so control system should have a layer to hide hardware details, Application Control Program access control devices through logical name but not through coded hardware address. Without this layer, it is difficult to develop application program which can access both 'Virtual' and 'Real' Accelerators using same program interfaces. For this reason, we can create CSR Runtime Database which allows application program to access hardware devices and data on a simulation process in a unified way. A device 'is represented as a collection of records in CSR Runtime Database. A control program on host computer can access devices in the system only through names of record fields, called channel.

  8. A Survey of Hadron Therapy Accelerator Technologies.

    Energy Technology Data Exchange (ETDEWEB)

    PEGGS,S.; SATOGATA, T.; FLANZ, J.

    2007-06-25

    Hadron therapy has entered a new age [1]. The number of facilities grows steadily, and 'consumer' interest is high. Some groups are working on new accelerator technology, while others optimize existing designs by reducing capital and operating costs, and improving performance. This paper surveys the current requirements and directions in accelerator technology for hadron therapy.

  9. Active Affective Learning for Accelerated Schools.

    Science.gov (United States)

    Richardson, Robert B.

    This paper provides the groundwork for Active Affective Learning and teaching adapted to the needs of the disadvantaged, at-risk students served by the Accelerated Schools Movement. One of the "golden rules" for the practice of Accelerated Learning, according to psychiatrist Georgi Lozanov, has been to maintain an "up-beat" classroom presentation…

  10. Quantum optical device accelerating dynamic programming

    OpenAIRE

    Grigoriev, D.; Kazakov, A.; Vakulenko, S

    2005-01-01

    In this paper we discuss analogue computers based on quantum optical systems accelerating dynamic programming for some computational problems. These computers, at least in principle, can be realized by actually existing devices. We estimate an acceleration in resolving of some NP-hard problems that can be obtained in such a way versus deterministic computers

  11. Notes on beam dynamics in linear accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Gluckstern, R.L.

    1980-09-01

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

  12. Proton-driven plasma acceleration at CERN

    International Nuclear Information System (INIS)

    Plasma-based acceleration methods have seen important progress over the last years. Recently, it has been proposed to experimentally study plasma acceleration driven by proton beams, in addition to the established research directions of electron and laser-driven plasmas. This talk presents the planned experiment and the research efforts carried out at CERN.

  13. Advocating for Grade-Based Acceleration

    Science.gov (United States)

    Guilbault, Keri M.

    2014-01-01

    Parents often struggle with the decision to accelerate their child and may worry about social and emotional issues, although research indicates positive effects on the social and emotional adjustment of carefully selected accelerants. As children's advocates, parents can work effectively with a school system to secure an appropriate academic…

  14. The deuteron accelerator preliminary design for BISOL

    Science.gov (United States)

    Peng, S. X.; Zhu, F.; Wang, Z.; Gao, Y.; Guo, Z. Y.

    2016-06-01

    BISOL, which was named as Beijing_ISOL before (Cui et al., 2013), is the abbreviation of Beijing Isotope-Separation-On-Line neutron beam facility. It is proposed jointly by Peking University (PKU) and China Institute of Atomic Energy (CIAE) for basic science study and application. It is a double driven facility that can be driven by a reactor or a deuteron accelerator. The deuteron driver accelerator should accelerate the deuteron beam up to 40 MeV with maximum beam current of 10 mA. Proton beams up to 33 MeV and He2+ beams up to 81.2 MeV can also be accelerated in this accelerator. The accelerator can be operated on either CW (continuous waveform) or pulsed mode, and the ion energy can be adjusted in a wide range. The accelerator will also allow independent operation of the RIB (Radioactive Ion Beams) system. It will be mainly charged by PKU group. Details of the deuteron accelerator preliminary design for BISOL will be given in this paper.

  15. Accelerating scientific publication in biology.

    Science.gov (United States)

    Vale, Ronald D

    2015-11-01

    Scientific publications enable results and ideas to be transmitted throughout the scientific community. The number and type of journal publications also have become the primary criteria used in evaluating career advancement. Our analysis suggests that publication practices have changed considerably in the life sciences over the past 30 years. More experimental data are now required for publication, and the average time required for graduate students to publish their first paper has increased and is approaching the desirable duration of PhD training. Because publication is generally a requirement for career progression, schemes to reduce the time of graduate student and postdoctoral training may be difficult to implement without also considering new mechanisms for accelerating communication of their work. The increasing time to publication also delays potential catalytic effects that ensue when many scientists have access to new information. The time has come for life scientists, funding agencies, and publishers to discuss how to communicate new findings in a way that best serves the interests of the public and the scientific community.

  16. Damped and detuned accelerator structures

    Energy Technology Data Exchange (ETDEWEB)

    Deruyter, H.; Farkas, Z.D; Hoag, H.A.; Ko, K.; Kroll, N.; Loew, G.A.; Miller, R.; Palmer, R.B.; Paterson, J.M.; Thompson, K.A.; Wang, J.W.; Wilson, P.B.

    1990-09-01

    This paper reports continuing work on accelerator structures for future TeV linear colliders. These structures, in addition to having to operate at high gradients, must minimize the effects of wakefield modes which are induced by e{sup {plus minus}} bunch trains. Two types of modified disk-loaded waveguides are under investigation: damped structures in which the wakefield power is coupled out to lossy regions through radial slots in the disks and/or azimuthal rectangular waveguides, whereby the external Q of the undesirable HEM{sub 11} mode is lowered to values below 20, and detuned structures in which the frequencies of these modes are modified from one end to the other of each section by {approximately}10%, thereby scrambling their effects on the beam. Beam dynamics calculations indicate that these two approaches are roughly equivalent. MAFIA, ARGUS and URMEL codes have been used extensively in conjunction with low-power tests on S- and X-band models to identify mode patterns, dispersion curves and Q values, and to demonstrate damping or detuning of the HEM modes. Results of calculations and measurements on the various structures are presented and evaluated.

  17. Ocean acidification accelerates reef bioerosion.

    Directory of Open Access Journals (Sweden)

    Max Wisshak

    Full Text Available In the recent discussion how biotic systems may react to ocean acidification caused by the rapid rise in carbon dioxide partial pressure (pCO(2 in the marine realm, substantial research is devoted to calcifiers such as stony corals. The antagonistic process - biologically induced carbonate dissolution via bioerosion - has largely been neglected. Unlike skeletal growth, we expect bioerosion by chemical means to be facilitated in a high-CO(2 world. This study focuses on one of the most detrimental bioeroders, the sponge Cliona orientalis, which attacks and kills live corals on Australia's Great Barrier Reef. Experimental exposure to lowered and elevated levels of pCO(2 confirms a significant enforcement of the sponges' bioerosion capacity with increasing pCO(2 under more acidic conditions. Considering the substantial contribution of sponges to carbonate bioerosion, this finding implies that tropical reef ecosystems are facing the combined effects of weakened coral calcification and accelerated bioerosion, resulting in critical pressure on the dynamic balance between biogenic carbonate build-up and degradation.

  18. Accelerator experiments for the unification

    International Nuclear Information System (INIS)

    The spectrum of the elementary particles known today sets the scale of our future explorations. It is dominated in the boson sector by the W-Z triplet, mw = 80.2 ± 0.2 GeV and mz = 91.189 ± 0.004 GeV, and in the fermion sector by the top quark, ml =175.5 ± 5.1 GeV. Supersymmetric models imply the existence of many undiscovered particles that would be the partners of the particles, which we know today. Most models predict that several of them should populate the 100 - 1000 GeV mass ranges in which the Higgs mechanism is expected to operate. Our current knowledge of the particle world points to a mass range extending typically an order of magnitude above the W-Z mass for future exploration. In order to reach the large mass at which we target, the new accelerators must be operated in the collider mode rather than in the fixed target mode. In practice pp and e+e- colliders are only the tools able to reach such luminosity. Synchrotron radiation losses prevent the operation of e+e- colliders above the LEP-2 energy range (80 GeV). In pp case, synchrotron radiation losses remain small and a circular design can be maintained. (author)

  19. Is cosmic acceleration slowing down?

    CERN Document Server

    Shafieloo, Arman; Starobinsky, Alexei A

    2009-01-01

    An investigation of dark energy (DE) using the Constitution SnIa sample (which includes recent CfA data at low redshifts) reveals a slight inconsistency (more than 1$\\sigma$) with the standard spatially flat LCDM model, if the assumption of a constant equation of state (w) for DE is dropped. This effect, which is most clearly seen using the recently introduced Om diagnostic, corresponds to an increase of Om and w at redshifts z<0.3. In geometrical terms, this suggests that cosmic acceleration may have already peaked and that we are currently witnessing its slowing down. Interestingly, such DE behaviour also provides a better fit to baryon acoustic oscillation (BAO) data. Including the cosmic microwave background (CMB) `shift parameter' as another independent observable, we show that the well known CPL parametrization is strained to fit the data simultaneously at low and high redshifts. This could either be because of the presence of systematics, or because the CPL ansatz is not versatile enough to catch th...

  20. Accelerated dry curing of hams.

    Science.gov (United States)

    Marriott, N G; Kelly, R F; Shaffer, C K; Graham, P P; Boling, J W

    1985-01-01

    Uncured pork legs from the right side of 18 carcasses were treated with a Ross Tenderizer and the left side were controls. All 36 samples were dry-cured for 40, 56 or 70 days and evaluated for appearance traits, cure penetration characteristics, microbial load, Kramer Shear force and taste attributes. The tenderization treatment had no effect (P > 0·05) on visual color or cure penetration rate, weight loss before curing, percentage moisture, nitrate level, nitrite level, total plate count, anaerobic counts, psychrotrophic counts, objective and subjective tenderness measurements or juiciness. However, the higher values of salt suggested a possible acceleration of the dry cure penetration process among the tenderized samples. Cure time had no effect (P > 0·05) on percentage moisture, percentage salt, nitrate content, nitrite content, shear force and juiciness. Results suggest a limited effect of the mechanical tenderization process on certain traits related to dry curing and that total process time should be at least 70 days if color stability during cooking is desired. PMID:22056076