Science.gov

Sample records for colliding beam accelerator

  1. A DSP based data acquisition module for colliding beam accelerators

    SciTech Connect

    Mead, J.A.; Shea, T.J.

    1995-10-01

    In 1999, the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory will accelerate and store two beams of gold ions. The ions will then collide head on at a total energy of nearly 40 trillion electron volts. Attaining these conditions necessitates real-time monitoring of beam parameters and for this purpose a flexible data acquisition platform has been developed. By incorporating a floating point digital signal processor (DSP) and standard input/output modules, this system can acquire and process data from a variety of beam diagnostic devices. The DSP performs real time corrections, filtering, and data buffering to greatly reduce control system computation and bandwidth requirements. We will describe the existing hardware and software while emphasizing the compromises required to achieve a flexible yet cost effective system. Applications in several instrumentation systems currently construction will also be presented.

  2. High Energy Accelerator and Colliding Beam User Group

    SciTech Connect

    Snow, G.A.; Skuja, A.

    1992-05-01

    This report discusses research in the following areas: the study of e{sup +}e{sup {minus}} interactions; Hadron collider physics at Fermilab; fixed target physics and particle physics of general interest; and, the solenoidal detector collaboration at SSCL.

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

    SciTech Connect

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

    2014-09-09

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

  4. Online beam energy measurement of Beijing electron positron collider II linear accelerator.

    PubMed

    Wang, S; Iqbal, M; Liu, R; Chi, Y

    2016-02-01

    This paper describes online beam energy measurement of Beijing Electron Positron Collider upgraded version II linear accelerator (linac) adequately. It presents the calculation formula, gives the error analysis in detail, discusses the realization in practice, and makes some verification. The method mentioned here measures the beam energy by acquiring the horizontal beam position with three beam position monitors (BPMs), which eliminates the effect of orbit fluctuation, and is much better than the one using the single BPM. The error analysis indicates that this online measurement has further potential usage such as a part of beam energy feedback system. The reliability of this method is also discussed and demonstrated in this paper. PMID:26931839

  5. Online beam energy measurement of Beijing electron positron collider II linear accelerator

    NASA Astrophysics Data System (ADS)

    Wang, S.; Iqbal, M.; Liu, R.; Chi, Y.

    2016-02-01

    This paper describes online beam energy measurement of Beijing Electron Positron Collider upgraded version II linear accelerator (linac) adequately. It presents the calculation formula, gives the error analysis in detail, discusses the realization in practice, and makes some verification. The method mentioned here measures the beam energy by acquiring the horizontal beam position with three beam position monitors (BPMs), which eliminates the effect of orbit fluctuation, and is much better than the one using the single BPM. The error analysis indicates that this online measurement has further potential usage such as a part of beam energy feedback system. The reliability of this method is also discussed and demonstrated in this paper.

  6. High energy accelerator and colliding beam user group

    SciTech Connect

    Not Available

    1990-09-01

    This report discusses the following topics: OPAL experiment at LEP; D{phi} experiment at Fermilab; deep inelastic muon interactions at TEV II; CYGNUS experiment; final results from {nu}{sub e}{sup {minus}e} elastic scattering; physics with CLEO detector at CESR; results from JADE at PETRA; rare kaon-decay experiment at BNL; search for top quark; and super conducting super collider activities.

  7. The generation and acceleration of low emittance flat beams for future linear colliders

    SciTech Connect

    Raubenheimer, T.O.

    1991-11-01

    Many future linear collider designs call for electron and positron beams with normalized rms horizontal and vertical emittances of {gamma}{epsilon}{sub x} = 3{times}10{sup {minus}6} m-rad and {gamma}{epsilon}{sub y} = 3{times}10{sup {minus}8} m-rad; these are a factor of 10 to 100 below those observed in the Stanford Linear Collider. In this dissertation, we examine the feasibility of achieving beams with these very small vertical emittances. We examine the limitations encountered during both the generation and the subsequent acceleration of such low emittance beams. We consider collective limitations, such as wakefields, space charge effects, scattering processes, and ion trapping; and also how intensity limitations, such as anomalous dispersion, betatron coupling, and pulse-to-pulse beam jitter. In general, the minimum emittance in both the generation and the acceleration stages is limited by the transverse misalignments of the accelerator components. We describe a few techniques of correcting the effect of these errors, thereby easing the alignment tolerances by over an order of magnitude. Finally, we also calculate ``fundamental`` limitations on the minimum vertical emittance; these do not constrain the current designs but may prove important in the future.

  8. The generation and acceleration of low emittance flat beams for future linear colliders

    SciTech Connect

    Raubenheimer, T.O.

    1991-11-01

    Many future linear collider designs call for electron and positron beams with normalized rms horizontal and vertical emittances of {gamma}{epsilon}{sub x} = 3{times}10{sup {minus}6} m-rad and {gamma}{epsilon}{sub y} = 3{times}10{sup {minus}8} m-rad; these are a factor of 10 to 100 below those observed in the Stanford Linear Collider. In this dissertation, we examine the feasibility of achieving beams with these very small vertical emittances. We examine the limitations encountered during both the generation and the subsequent acceleration of such low emittance beams. We consider collective limitations, such as wakefields, space charge effects, scattering processes, and ion trapping; and also how intensity limitations, such as anomalous dispersion, betatron coupling, and pulse-to-pulse beam jitter. In general, the minimum emittance in both the generation and the acceleration stages is limited by the transverse misalignments of the accelerator components. We describe a few techniques of correcting the effect of these errors, thereby easing the alignment tolerances by over an order of magnitude. Finally, we also calculate fundamental'' limitations on the minimum vertical emittance; these do not constrain the current designs but may prove important in the future.

  9. Muon Collider Progress: Accelerators

    SciTech Connect

    Zisman, Michael S.

    2011-09-10

    A muon collider would be a powerful tool for exploring the energy-frontier with leptons, and would complement the studies now under way at the LHC. Such a device would offer several important benefits. Muons, like electrons, are point particles so the full center-of-mass energy is available for particle production. Moreover, on account of their higher mass, muons give rise to very little synchrotron radiation and produce very little beamstrahlung. The first feature permits the use of a circular collider that can make efficient use of the expensive rf system and whose footprint is compatible with an existing laboratory site. The second feature leads to a relatively narrow energy spread at the collision point. Designing an accelerator complex for a muon collider is a challenging task. Firstly, the muons are produced as a tertiary beam, so a high-power proton beam and a target that can withstand it are needed to provide the required luminosity of ~1 × 10{sup 34} cm{sup –2}s{sup –1}. Secondly, the beam is initially produced with a large 6D phase space, which necessitates a scheme for reducing the muon beam emittance (“cooling”). Finally, the muon has a short lifetime so all beam manipulations must be done very rapidly. The Muon Accelerator Program, led by Fermilab and including a number of U.S. national laboratories and universities, has undertaken design and R&D activities aimed toward the eventual construction of a muon collider. Design features of such a facility and the supporting R&D program are described.

  10. Collective accelerator for electron colliders

    SciTech Connect

    Briggs, R.J.

    1985-05-13

    A recent concept for collective acceleration and focusing of a high energy electron bunch is discussed, in the context of its possible applicability to large linear colliders in the TeV range. The scheme can be considered to be a member of the general class of two-beam accelerators, where a high current, low voltage beam produces the acceleration fields for a trailing high energy bunch.

  11. Beam collimation at hadron colliders

    SciTech Connect

    Nikolai V. Mokhov

    2003-08-12

    Operational and accidental beam losses in hadron colliders can have a serious impact on machine and detector performance, resulting in effects ranging from minor to catastrophic. Principles and realization are described for a reliable beam collimation system required to sustain favorable background conditions in the collider detectors, provide quench stability of superconducting magnets, minimize irradiation of accelerator equipment, maintain operational reliability over the life of the machine, and reduce the impact of radiation on personnel and the environment. Based on detailed Monte-Carlo simulations, such a system has been designed and incorporated in the Tevatron collider. Its performance, comparison to measurements and possible ways to further improve the collimation efficiency are described in detail. Specifics of the collimation systems designed for the SSC, LHC, VLHC, and HERA colliders are discussed.

  12. COLLIDING CRYSTALLINE BEAMS.

    SciTech Connect

    WEI, J.

    1998-06-26

    The understanding of crystalline beams has advanced to the point where one can now, with reasonable confidence, undertake an analysis of the luminosity of colliding crystalline beams. Such a study is reported here. It is necessary to observe the criteria, previously stated, for the creation and stability of crystalline beams. This requires, firstly, the proper design of a lattice. Secondly, a crystal must be formed, and this can usually be done at various densities. Thirdly, the crystals in a colliding-beam machine are brought into collision. We study all of these processes using the molecular dynamics (MD) method. The work parallels what was done previously, but the new part is to study the crystal-crystal interaction in collision. We initially study the zero-temperature situation. If the beam-beam force (or equivalent tune shift) is too large then overlapping crystals can not be created (rather two spatially separated crystals are formed). However, if the beam-beam force is less than but comparable to that of the space-charge forces between the particles, we find that overlapping crystals can be formed and the beam-beam tune shift can be of the order of unity. Operating at low but non-zero temperature can increase the luminosity by several orders of magnitude over that of a usual collider. The construction of an appropriate lattice, and the development of adequately strong cooling, although theoretically achievable, is a challenge in practice.

  13. Colliding crystalline beams

    SciTech Connect

    Wei, J.; Sessler, A.M.

    1998-08-01

    The understanding of crystalline beams has advanced to the point where one can now, with reasonable confidence, undertake an analysis of the luminosity of colliding crystalline beams. Such a study is reported here. It is necessary to observe the criteria, previously stated, for the creation and stability of crystalline beams. This requires, firstly, the proper design of a lattice. Secondly, a crystal must be formed, and this can usually be done at various densities. Thirdly, the crystals in a colliding-beam machine are brought into collision. The authors study all of these processes using the molecular dynamics (MD) method. The work parallels what was done previously, but the new part is to study the crystal-crystal interaction in collision. They initially study the zero-temperature situation. If the beam-beam force (or equivalent tune shift) is too large then overlapping crystals can not be created (rather two spatially separated crystals are formed). However, if the beam-beam force is less than but comparable to that of the space-charge forces between the particles, they find that overlapping crystals can be formed and the beam-beam tune shift can be of the order of unity. Operating at low but non-zero temperature can increase the luminosity by several orders of magnitude over that of a usual collider. The construction of an appropriate lattice, and the development of adequately strong cooling, although theoretically achievable, is a challenge in practice.

  14. Studies of the chromatic properties and dynamic aperture of the BNL colliding-beam accelerator. [PATRICIA particle tracking code

    SciTech Connect

    Dell, G.F.

    1983-01-01

    The PATRICIA particle tracking program has been used to study chromatic effects in the Brookhaven CBA (Colliding Beam Accelerator). The short term behavior of particles in the CBA has been followed for particle histories of 300 turns. Contributions from magnet multipoles characteristic of superconducting magnets and closed orbit errors have been included in determining the dynamic aperture of the CBA for on and off momentum particles. The width of the third integer stopband produced by the temperature dependence of magnetization induced sextupoles in the CBA cable dipoles is evaluated for helium distribution systems having periodicity of one and six. The stopband width at a tune of 68/3 is naturally zero for the system having a periodicity of six and is approx. 10/sup -4/ for the system having a periodicity of one. Results from theory are compared with results obtained with PATRICIA; the results agree within a factor of slightly more than two.

  15. High Energy Accelerator and Colliding Beam User Group. Progress report, March 1, 1992--October 31, 1992

    SciTech Connect

    Snow, G.A.; Skuja, A.

    1992-05-01

    This report discusses research in the following areas: the study of e{sup +}e{sup {minus}} interactions; Hadron collider physics at Fermilab; fixed target physics and particle physics of general interest; and, the solenoidal detector collaboration at SSCL.

  16. FFAG Designs for Muon Collider Acceleration

    SciTech Connect

    Berg, J. Scott

    2014-01-13

    I estimate FFAG parameters for a muon collider with a 70mm longitudinal emittance. I do not discuss the lower emittance beam for a Higgs factory. I produce some example designs, giving only parameters relevant to estimating cost and performance. The designs would not track well, but the parameters of a good design will be close to those described. I compare these cost estimates to those for a fast-ramping synchrotron and a recirculating linear accelerator. I conclude that FFAGs do not appear to be cost-effective for the large longitudinal emittance in a high-energy muon collider.

  17. Proton-proton colliding beam facility ISABELLE

    SciTech Connect

    Hahn, H

    1980-01-01

    This paper attempts to present the status of the ISABELLE construction project, which has the objective of building a 400 + 400 GeV proton colliding beam facility. The major technical features of the superconducting accelerators with their projected performance are described. Progress made so far, difficulties encountered, and the program until completion in 1986 is briefly reviewed.

  18. The Next Linear Collider Test Accelerator

    SciTech Connect

    Ruth, R.D.; Adolphsen, C.; Bane, K.

    1993-04-01

    During the past several years, there has been tremendous progress the development of the RF system and accelerating structures for a Next Linear Collider (NLC). Developments include high-power klystrons, RF pulse compression systems and damped/detuned accelerator structures to reduce wakefields. In order to integrate these separate development efforts into an actual X-band accelerator capable of accelerating the electron beams necessary for an NLC, we are building an NLC Test Accelerator (NLCTA). The goal of the NLCTA is to bring together all elements of the entire accelerating system by constructing and reliably operating an engineered model of a high-gradient linac suitable for the NLC. The NLCTA will serve as a testbed as the design of the NLC evolves. In addition to testing the RF acceleration system, the NLCTA is designed to address many questions related to the dynamics of the beam during acceleration. In this paper, we will report oil the status of the design, component development, and construction of the NLC Test Accelerator.

  19. Accelerator physics of the Stanford Linear Collider and SLC accelerator experiments towards the Next Linear Collider

    SciTech Connect

    Seeman, J.T.

    1992-06-01

    The Stanford Linear Collider (SLC) was built to collide single bunches of electrons and positrons head-on at a single interaction point with single beam energies up to 55 GeV. The small beam sizes and high currents required for high luminosity operation have significantly pushed traditional beam quality limits. The Polarized Electron Source produces about 8 {times} 10{sup 10} electrons in each of two bunches with up to 28% polarization,. The Damping Rings provide coupled invariant emittances of 1.8 {times} 10{sup {minus}5} r-m with 4.5 {times} 10{sup 10} particles per bunch. The 57 GeV Linac has successfully accelerated over 3 {times} 10{sup 10} particles with design invariant emittances of 3 {times} 10{sup {minus}5} r-m. Both longitudinal and transverse wakefields affect strongly the trajectory and emittance corrections used for operations. The Arc systems routinely transport decoupled and betatron matched beams. In the Final Focus, the beams are chromatically corrected and demagnified producing spot sizes of 2 to 3 {mu}m at the focal point. Spot sizes below 2 {mu}m have been made during special tests. Instrumentation and feedback systems are well advanced, providing continuous beam monitoring and pulse-by-pulse control. A luminosity of 1.6 {times} 10{sup 29} cm{sup {minus}2}sec{sup {minus}1} has been produced. Several experimental tests for a Next Linear Collider (NLC) are being planned or constructed using the SLC accelerator as a test facility. The Final Focus Test Beam will demagnify a flat 50 GeV electron beam to dimensions near 60 nm vertically and 900 nm horizontally. A potential Emittance Dynamics Test Area has the capability to test the acceleration and transport of very low emittance beams, the compression of bunch lengths to 50 {mu}m, the acceleration and control of multiple bunches, and the properties of wakefields in the very short bunch length regime.

  20. Preliminary design report of a relativistic-Klystron two-beam-accelerator based power source for a 1 TeV center-of-mass next linear collider

    SciTech Connect

    Yu, S.; Goffeney, N.; Henestroza, E.

    1995-02-22

    A preliminary point design for an 11.4 GHz power source for a 1 TeV center-of-mass Next Linear Collider (NLC) based on the Relativistic-Klystron Two-Beam-Accelerator (RK-TBA) concept is presented. The present report is the result of a joint LBL-LLNL systems study. consisting of three major thrust areas: physics, engineering, and costing. The new RK-TBA point design, together with our findings in each of these areas, are reported.

  1. Stability of colliding ion beams

    SciTech Connect

    Foote, E.A.; Kulsrud, R.M.

    1980-11-01

    We determine conditions for stability of two identical colliding ion beams in the presence of neutralizing electrons, but no background ions. Such a situation is envisioned for the Counterstreaming Ion Torus. The ion beams are taken to be Maxwellian in their frames of reference. The approximation of electrostatic and electromagnetic modes is made. The stability of the electrostatic modes depends on the relation between the ion electron temperature ratio and the relative beam velocities. The stability of the electromagnetic mode depends on the relation between the ion plasma ..beta.. and the relative beam velocities.

  2. Two-beam accelerator

    SciTech Connect

    Selph, F.B.

    1984-09-01

    In the two-beam accelerator (TBA) concept, an electron linear accelerator structure is established in which two beams propagate. One is an intense low energy beam that is made to undergo free electron lasing to produce microwaves. These microwaves are then coupled to another part of the structure where they act to produce a high longitudinal electric gradient that is used to accelerate a second relatively low intensity electron beam to very high energies. The TBA was originally suggested by Sessler as a possible means for economically achieving linear collider energies of 100 GeV and above. Although still in a conceptual stage, the TBA is an inherently plausible concept that combines the free electron laser (FEL) with several well-known technologies - high current induction linacs, microwave waveguides, and traveling-wave linac structures - in a novel and interesting way. Two characteristics of the TBA that make it a particularly suitable candidate for achieving high energies are its ability to operate at higher frequencies than typical present-day linacs (say 30 GHz as compared with 3 GHz), and to be an efficient means for delivering power to a hitherto unattainable high-gradient structure (say 250 MV/m) that the higher frequency makes possible. These high accelerating gradients will permit much shorter linac structures for a given energy.

  3. Beam dynamics issues in linear colliders

    SciTech Connect

    Seeman, J.T.

    1989-06-01

    The primary goal of present and future linear colliders is to maximize the integrated luminosity for the experimental program. Beam dynamics plays a central role in the maximization of integrated luminosity. It is the major issue in the production of small beam sizes and low experimental backgrounds and is also an important factor in the production of particle numbers, in the acceleration process, and in the number of bunches. The beam dynamics effects on bunches which are extracted from the damping rings, accelerated in the linac, collimated, momentum analyzed, and finally delivered to the final focus are reviewed. The effects of bunch compression, transverse and longitudinal wakefields, BNS damping, energy definition, dispersion, emittance, bunch aspect ratio, feedback, and stability are all important. 11 refs., 1 tab.

  4. PROTON BEAM REQUIREMENTS FOR A NEUTRINO FACTORY AND MUON COLLIDER

    SciTech Connect

    Zisman, Michael S.

    2009-12-11

    Both a Neutrino Factory and a Muon Collider place stringent demands on the proton beam used to generate the desired beam of muons. Here we discuss the advantages and challenges of muon accelerators and the rationale behind the requirements on proton beam energy, intensity, bunch length, and repetition rate. Example proton driver configurations that have been considered in recent years are also briefly indicated.

  5. Linear accelerators for TeV colliders

    SciTech Connect

    Wilson, P.B.

    1985-05-01

    This paper summarizes four tutorial lectures on linear electron accelerators: Electron Linacs for TeV Colliders, Emittance and Damping Rings, Wake Fields: Basic Concepts, and Wake Field Effects in Linacs.

  6. Colliding Laser Pulses for Laser-Plasma Accelerator Injection Control

    SciTech Connect

    Plateau, G. R.; Geddes, C. G. R.; Matlis, N. H.; Mittelberger, D. E.; Nakamura, K.; Schroeder, C. B.; Esarey, E.; Leemans, W. P.; Cormier-Michel, E.

    2010-11-04

    Decoupling injection from acceleration is a key challenge to achieve compact, reliable, tunable laser-plasma accelerators (LPA). In colliding pulse injection the beat between multiple laser pulses can be used to control energy, energy spread, and emittance of the electron beam by injecting electrons in momentum and phase into the accelerating phase of the wake trailing the driver laser pulse. At LBNL, using automated control of spatiotemporal overlap of laser pulses, two-pulse experiments showed stable operation and reproducibility over hours of operation. Arrival time of the colliding beam was scanned, and the measured timing window and density of optimal operation agree with simulations. The accelerator length was mapped by scanning the collision point.

  7. Colliding Laser Pulses for Laser-Plasma Accelerator Injection Control

    SciTech Connect

    Plateau, Guillaume; Geddes, Cameron; Matlis, Nicholas; Cormier-Michel, Estelle; Mittelberger, Daniel; Nakamura, Kei; Schroeder, Carl; Esarey, Eric; Leemans, Wim

    2011-07-19

    Decoupling injection from acceleration is a key challenge to achieve compact, reliable, tunable laser-plasma accelerators (LPA). In colliding pulse injection the beat between multiple laser pulses can be used to control energy, energy spread, and emittance of the electron beam by injecting electrons in momentum and phase into the accelerating phase of the wake trailing the driver laser pulse. At LBNL, using automated control of spatiotemporal overlap of laser pulses, two-pulse experiments showed stable operation and reproducibility over hours of operation. Arrival time of the colliding beam was scanned, and the measured timing window and density of optimal operation agree with simulations. The accelerator length was mapped by scanning the collision point.

  8. Accelerator physics in ERL based polarized electron ion collider

    SciTech Connect

    Hao, Yue

    2015-05-03

    This talk will present the current accelerator physics challenges and solutions in designing ERL-based polarized electron-hadron colliders, and illustrate them with examples from eRHIC and LHeC designs. These challenges include multi-pass ERL design, highly HOM-damped SRF linacs, cost effective FFAG arcs, suppression of kink instability due to beam-beam effect, and control of ion accumulation and fast ion instabilities.

  9. Future Accelerators, Muon Colliders, and Neutrino Factories

    SciTech Connect

    Richard A Carrigan, Jr.

    2001-12-19

    Particle physics is driven by five great topics. Neutrino oscillations and masses are now at the fore. The standard model with extensions to supersymmetry and a Higgs to generate mass explains much of the field. The origins of CP violation are not understood. The possibility of extra dimensions has raised tantalizing new questions. A fifth topic lurking in the background is the possibility of something totally different. Many of the questions raised by these topics require powerful new accelerators. It is not an overstatement to say that for some of the issues, the accelerator is almost the experiment. Indeed some of the questions require machines beyond our present capability. As this volume attests, there are parts of the particle physics program that have been significantly advanced without the use of accelerators such as the subject of neutrino oscillations and many aspects of the particle-cosmology interface. At this stage in the development of physics, both approaches are needed and important. This chapter first reviews the status of the great accelerator facilities now in operation or coming on within the decade. Next, midrange possibilities are discussed including linear colliders with the adjunct possibility of gamma-gamma colliders, muon colliders, with precursor neutrino factories, and very large hadron colliders. Finally visionary possibilities are considered including plasma and laser accelerators.

  10. Beam dynamics issues for linear colliders

    SciTech Connect

    Ruth, R.D.

    1987-09-01

    In this paper we discuss various beam dynamics issues for linear colliders. The emphasis is to explore beam dynamics effects which lead to an effective dilution of the emittance of the beam and thus to a loss of luminosity. These considerations lead to various tolerances which are evaluated for a particular parameter set.

  11. Acceleration and storage of polarized proton beams

    SciTech Connect

    Roser, T.

    1995-12-31

    High energy polarized beam collisions will open up the unique physics opportunities of studying spin effects in hard processes. Proposals for polarized proton acceleration for several high energy colliders have been developed. A partial Siberian Snake in the AGS has recently been successfully tested and full Siberian Snakes, spin rotators, and polarimeters for RHIC are being developed to make the acceleration of polarized beams to 250 GeV possible. This allows for the unique possibility of colliding two 250 GeV polarized proton beams at luminosities of up to 2 x 10{sup 32} cm{sup -2} s{sup -1}.

  12. The accuracy of beam-beam diagnostics for circular colliders

    SciTech Connect

    Ziemann, V.

    1992-08-01

    We investigate the potential of beam-beam deflection techniques for the determination of spot sizes, tilt angle, centering, and angular divergence for circular colliders. Achievable accuracies for all measured quantities are estimated.

  13. GPU-optimized Code for Long-term Simulations of Beam-beam Effects in Colliders

    SciTech Connect

    Roblin, Yves; Morozov, Vasiliy; Terzic, Balsa; Aturban, Mohamed A.; Ranjan, D.; Zubair, Mohammed

    2013-06-01

    We report on the development of the new code for long-term simulation of beam-beam effects in particle colliders. The underlying physical model relies on a matrix-based arbitrary-order symplectic particle tracking for beam transport and the Bassetti-Erskine approximation for beam-beam interaction. The computations are accelerated through a parallel implementation on a hybrid GPU/CPU platform. With the new code, a previously computationally prohibitive long-term simulations become tractable. We use the new code to model the proposed medium-energy electron-ion collider (MEIC) at Jefferson Lab.

  14. LASER-PLASMA-ACCELERATOR-BASED GAMMA GAMMA COLLIDERS

    SciTech Connect

    Schroeder, C. B.; Esarey, E.; Toth, Cs.; Geddes, C. G. R.; Leemans, W. P.

    2009-05-04

    Design considerations for a next-generation linear collider based on laser-plasma-accelerators are discussed, and a laser-plasma-accelerator-based gamma-gamma collider is considered. An example of the parameters for a 0.5 TeV laser-plasma-accelerator gamma gamma collider is presented.

  15. Collider and detector protection at beam accidents

    SciTech Connect

    I. L. Rakhno; N. V. Mokhov; A. I. Drozhdin

    2003-12-10

    Dealing with beam loss due to abort kicker prefire is considered for hadron colliders. The prefires occurred at Tevatron (Fermilab) during Run I and Run II are analyzed and a protection system implemented is described. The effect of accidental beam loss in the Large Hadron Collider (LHC) at CERN on machine and detector components is studied via realistic Monte Carlo calculations. The simulations show that beam loss at an unsynchronized beam abort would result in severe heating of conventional and superconducting magnets and possible damage to the collider detector elements. A proposed set of collimators would reduce energy deposition effects to acceptable levels. Special attention is paid to reducing peak temperature rise within the septum magnet and minimizing quench region length downstream of the LHC beam abort straight section.

  16. Advances in beam physics and technology: Colliders of the future

    SciTech Connect

    Chattopadhyay, S.

    1994-11-01

    Beams may be viewed as directed and focussed flow of energy and information, carried by particles and electromagnetic radiation fields (ie, photons). Often, they interact with each other (eg, in high energy colliders) or with other forms of matter (eg, in fixed targets, sychrotron radiation, neutron scattering, laser chemistry/physics, medical therapy, etc.). The whole art and science of beams revolve around the fundamental quest for, and ultimate implementation of, mechanisms of production, storage, control and observation of beams -- always directed towards studies of the basic structures and processes of the natural world and various practical applications. Tremendous progress has been made in all aspects of beam physics and technology in the last decades -- nonlinear dynamics, superconducting magnets and rf cavities, beam instrumentation and control, novel concepts and collider praradigms, to name a few. We illustrate this progress with a few examples and remark on the emergence of new collider scenarios where some of these progress might come to use -- the Gamma-Gamma Collider, the Muon Collider, laser acceleration, etc. We close with an outline of future oppotunities and outlook.

  17. TRANSVERSE BEAM TRANSFER FUNCTIONS OF COLLIDING BEAMS IN RHIC

    SciTech Connect

    FISCHER,W.; BLASKIEWICZ, M.; CALAGA, R.; CAMERON, P.; HERR, W.; PIELONI, T.

    2007-06-25

    We use transverse beam transfer functions to measure tune distributions of colliding beams in RHIC. The tune has a distribution due to the beam-beam interaction, nonlinear magnetic fields -- particularly in the interaction region magnets, and non-zero chromaticity in conjunction with momentum spread. The measured tune distributions are compared with calculations.

  18. Beam trajectory acquisition system for the arcs of the Stanford Linear Collider

    SciTech Connect

    Pellegrin, J.L.; Ross, M.C.; Scott, B.D.; Wilson, D.S.

    1987-02-01

    This report describes the beam position monitoring system of the collider arcs at the Stanford Linear Collider. This beam position monitoring system is different from others at SLAC in its large amount of hardware and its use of ungated, self-triggered electronics. All of the processing electronics are installed in the accelerator tunnel. (JDH)

  19. Fermilab collider run 1b accelerator performance

    SciTech Connect

    Bharadwaj, V.; Halling, M.; Lucas, P.; McCrory, E.; Mishra, S.; Pruss, S.; Werkema, S.

    1996-04-01

    This report summarizes the performance of Run 1b as of the end of July 1995. This run is the conclusion of Fermilab Collider Run 1, which consists of Run 1a (May 1992 - May 1993) and Run 1b (January 1994 - February 1996). Run 1b is characterized by being the first with the new 400 MeV Linac. At this time the run is not complete. Colliding beam physics is scheduled to resume after the summer 1995 shut down and continue until mid-February 1996. All of the operation to date is at a Tevatron energy of 900 GeV. This report emphasizes performance numbers and the various improvements made to systems to achieve this performance. It will only discuss the underlying physics to a limited extent. The report is divided into sections on: run statistics, I&C issues, proton source performance, antiproton source performance, main ring performance, Tevatron performance, and a summary.

  20. Beam instrumentation for the Tevatron Collider

    SciTech Connect

    Moore, Ronald S.; Jansson, Andreas; Shiltsev, Vladimir; /Fermilab

    2009-10-01

    The Tevatron in Collider Run II (2001-present) is operating with six times more bunches and many times higher beam intensities and luminosities than in Run I (1992-1995). Beam diagnostics were crucial for the machine start-up and the never-ending luminosity upgrade campaign. We present the overall picture of the Tevatron diagnostics development for Run II, outline machine needs for new instrumentation, present several notable examples that led to Tevatron performance improvements, and discuss the lessons for future colliders.

  1. Beam front accelerators

    SciTech Connect

    Reiser, M.

    1982-01-01

    An intense relativistic electron beam cannot propagate in a metal drift tube when the current exceeds the space charge limit. Very high charge density and electric field gradients (10/sup 2/ to 10/sup 3/ MV/m) develop at the beam front and the electrons are reflected. When a neutral gas or a plasma is present, collective acceleration of positive ions occur, and the resulting charge neutralization enables the beam to propagate. Experimental results, theoretical understanding, and schemes to achieve high ion energies by external control of the beam front velocity will be reviewed.

  2. Beam Instrumentation Challenges at the International Linear Collider

    SciTech Connect

    Tenenbaum, Peter; /SLAC

    2006-05-16

    The International Linear Collider (ILC) is a proposed facility for the study of high energy physics through electron-positron collisions at center-of-mass energies up to 500 GeV and luminosities up to 2 x 10{sup 34} cm{sup -2} sec{sup -1}. Meeting the ILC's goals will require an extremely sophisticated suite of beam instruments for the preservation of beam emittance, the diagnosis of optical errors and mismatches, the determination of beam properties required for particle physics purposes, and machine protection. The instrumentation foreseen for the ILC is qualitatively similar to equipment in use at other accelerator facilities in the world, but in many cases the precision, accuracy, stability, or dynamic range required by the ILC exceed what is typically available in today's accelerators. In this paper we survey the beam instrumentation requirements of the ILC and describe the system components which are expected to meet those requirements.

  3. Adiabatic disruption of asymmetric colliding beams

    SciTech Connect

    Katsouleas, T. . Dept. of Electrical Engineering Electrophysics); Wurtele, J.S. . Dept. of Physics)

    1991-01-01

    A scheme is considered for enhancing the luminosity of electron-positron colliders. One of the beams is taken to be much denser than the other and effectively becomes a lens for the second beam. The luminosity enhancement afforded by this asymmetric disruption process is estimated analytically. The scheme is severely limited by the kink instability which is characterized by a two-stream dispersion relation, and a constraint on the density of the less dense beam is found for which the instability is gradient stabilized.

  4. Adiabatic disruption of asymmetric colliding beams

    SciTech Connect

    Katsouleas, T.; Wurtele, J.S.

    1991-12-31

    A scheme is considered for enhancing the luminosity of electron-positron colliders. One of the beams is taken to be much denser than the other and effectively becomes a lens for the second beam. The luminosity enhancement afforded by this asymmetric disruption process is estimated analytically. The scheme is severely limited by the kink instability which is characterized by a two-stream dispersion relation, and a constraint on the density of the less dense beam is found for which the instability is gradient stabilized.

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

    SciTech Connect

    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.

  6. RF properties of periodic accelerating structures for linear colliders

    SciTech Connect

    Wang, J.W.

    1989-07-01

    With the advent of the SLAC electron-positron linear collider (SLC) in the 100 GeV center-of-mass energy range, research and development work on even higher energy machines of this type has started in several laboratories in the United States, Europe, the Soviet Union and Japan. These linear colliders appear to provide the only promising approach to studying e/sup /plus//e/sup /minus// physics at center-of-mass energies approaching 1 TeV. This thesis concerns itself with the study of radio frequency properties of periodic accelerating structures for linear colliders and their interaction with bunched beams. The topics that have been investigated are: experimental measurements of the energy loss of single bunches to longitudinal modes in two types of structures, using an equivalent signal on a coaxial wire to simulate the beam; a method of canceling the energy spread created within a single bunch by longitudinal wakefields, through appropriate shaping of the longitudinal charge distribution of the bunch; derivation of the complete transient beam-loading equation for a train of bunches passing through a constant-gradient accelerator section, with application to the calculation and minimization of multi-bunch energy spread; detailed study of field emission and radio frequency breakdown in disk-loaded structures at S-, C- and X-band frequencies under extremely high-gradient conditions, with special attention to thermal effects, radiation, sparking, emission of gases, surface damage through explosive emission and its possible control through RF-gas processing. 53 refs., 49 figs., 9 tabs.

  7. 62-TeV center of mass hadron collider with capability for super bunch beams

    SciTech Connect

    Ryuji Yamada and Ken Takayama

    2001-08-22

    A 60 TeV center of mass hadron collider is proposed, which has capability of using Superbunch beam. With Superbunch beam, the luminosity is expected to be increased by a factor of 20, compared with conventional acceleration using RF cavities. This hadron collider will be built in two stages with a low field magnet ring first and a high field magnet ring later in the same tunnel. The low field magnet rig will be built with Pipetron scheme, with 7 TeV and 7 TeV proton beams, making a 14 TeV center of mass energy high luminosity collider, using Superbunch beams. In the second stage 10 Tesla high field magnets with twin beams, will be installed. It also utilizes Superbunch beams, realizing high luminosity collider. To accelerate Superbunch beams, the barrier bucket and acceleration induction cells will be used, which are made of induction cells, utilizing FINEMET material. The core loss of the FINEMET is estimated for the whole collider is estimated. The synchrotron radiation of the collider is also estimated. Merits of Superbunch beams over RF bunched beams for the high energy experiments is described.

  8. Accelerator physics and technology challenges of very high energy hadron colliders

    SciTech Connect

    Shiltsev, Vladimir D.

    2015-08-20

    High energy hadron colliders have been in the forefront of particle physics for more than three decades. At present, international particle physics community considers several options for a 100TeV protonproton collider as a possible post-LHC energy frontier facility. The method of colliding beams has not fully exhausted its potential but has slowed down considerably in its progress. This article briefly reviews the accelerator physics and technology challenges of the future very high energy colliders and outlines the areas of required research and development towards their technical and financial feasibility.

  9. Accelerator physics and technology challenges of very high energy hadron colliders

    DOE PAGESBeta

    Shiltsev, Vladimir D.

    2015-08-20

    High energy hadron colliders have been in the forefront of particle physics for more than three decades. At present, international particle physics community considers several options for a 100 TeV proton–proton collider as a possible post-LHC energy frontier facility. The method of colliding beams has not fully exhausted its potential but has slowed down considerably in its progress. This article briefly reviews the accelerator physics and technology challenges of the future very high energy colliders and outlines the areas of required research and development towards their technical and financial feasibility.

  10. The International Linear Collider Beam Dumps

    SciTech Connect

    Appleby, R.; Keller, L.; Markiewicz, T.; Seryi, A.; Walz, D.; Sugahara, R.; /KEK, Tsukuba

    2006-01-30

    The ILC beam dumps are a key part of the accelerator design. At Snowmass 2005, the current status of the beam dump designs was reviewed, and the options for the overall dump layout considered. This paper describes the available dump options for the baseline and the alternatives and considers issues for the dumps that require resolution.

  11. High Energy Photon Beam Generation For QCD Explorer Based {gamma}P Colliders

    SciTech Connect

    Ciftci, A. K.; Aksakal, H.; Nergiz, Z.

    2007-04-23

    Combination of two linear accelerator projects, namely CLIC (Compact Linear Collider) and ILC (International Linear Collider) with LHC(Large Hadron Collider) offer an opportunity to build {gamma}p collider. High energy photons are produced by the Compton backscattering of the laser photons off high energy electrons at the conversion region. Then, Compton backscattered photons are collided with protons at the interaction region. In this study, conversion properties and optimum laser and electron beam parameters for CLIC and ILC are determined using CAIN simulation program.

  12. Beam-beam observations in the Relativistic Heavy Ion Collider

    SciTech Connect

    Luo, Y.; Fischer, W.; White, S.

    2015-06-24

    The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory has been operating since 2000. Over the past decade, thanks to the continuously increased bunch intensity and reduced β*s at the interaction points, the maximum peak luminosity in the polarized proton operation has been increased by more than two orders of magnitude. In this article, we first present the beam-beam observations in the previous RHIC polarized proton runs. Then we analyze the mechanisms for the beam loss and emittance growth in the presence of beam-beam interaction. The operational challenges and limitations imposed by beam-beam interaction and their remedies are also presented. In the end, we briefly introduce head-on beam-beam compensation with electron lenses in RHIC.

  13. On the luminosity of heteroenergetic colliding-beam storage rings

    SciTech Connect

    Rees, J.

    1988-02-01

    We shall estimate how the luminosity of a heteroenergetic colliding-beam storage-ring system is likely to be restrained by the incoherent beam-beam limit - or, in other words, by the tune-shift limit.

  14. FUTURE LEPTON COLLIDERS AND LASER ACCELERATION

    SciTech Connect

    PARSA,Z.

    2000-05-30

    Future high energy colliders along with their physics potential, and relationship to new laser technology are discussed. Experimental approaches and requirements for New Physics exploration are also described.

  15. SciDAC advances in beam dynamics simulation: from light sources to colliders

    SciTech Connect

    Qiang, Ji; Qiang, J.; Borland, M.; Kabel, A.; Li, R.; Ryne, R.; Stern, E.; Wang, Y.; Wasserman, H.; Zhang, Y.

    2008-06-16

    In this paper, we report on progress that has been made in beam dynamics simulation, from light sources to colliders, during the first year of SciDAC-II accelerator project,"Community Petascale Project for Accelerator Science and Simulation (ComPASS)." Several parallel computational tools for beam dynamics simulation will be described. A number of applications in current and future accelerator facilities, e.g., LCLS, RHIC, Tevatron, LHC, ELIC, are presented.

  16. Beam dynamics design of the Compact Linear Collider Drive Beam injector

    NASA Astrophysics Data System (ADS)

    Hajari, Sh. Sanaye; Shaker, H.; Doebert, S.

    2015-11-01

    In the Compact Linear Collider (CLIC) the RF power for the acceleration of the Main Beam is extracted from a high-current Drive Beam that runs parallel to the main linac. The longitudinal and transverse beam dynamics of the Drive Beam injector has been studied in detail and optimized. The injector consists of a thermionic gun followed by a bunching system, some accelerating structures, and a magnetic chicane. The bunching system contains three sub-harmonic bunchers, a prebuncher, and a traveling wave buncher all embedded in a solenoidal magnetic field. The main characteristic of the Drive Beam injector is the phase coding process done by the sub-harmonic bunching system operating at half the acceleration frequency. This process is essential for the frequency multiplication of the Drive Beam. During the phase coding process the unwanted satellite bunches are produced that adversely affects the machine power efficiency. The main challenge is to reduce the population of particles in the satellite bunches in the presence of strong space-charge forces due to the high beam current. The simulation of the beam dynamics has been carried out with PARMELA with the goal of optimizing the injector performance compared to the existing model studied for the Conceptual Design Report (CDR). The emphasis of the optimization was on decreasing the satellite population, the beam loss in the magnetic chicane and limiting the beam emittance growth in transverse plane.

  17. Status and future directions for advanced accelerator research - conventional and non-conventional collider concepts

    SciTech Connect

    Siemann, R.H.

    1997-01-01

    The relationship between advanced accelerator research and future directions for particle physics is discussed. Comments are made about accelerator research trends in hadron colliders, muon colliders, and e{sup +}3{sup {minus}} linear colliders.

  18. Two-Beam Accelerator: structure studies and 35 GHz experiments

    SciTech Connect

    Hopkins, D.B.; Kuenning, R.W.

    1985-05-01

    The Two-Beam Accelerator (TBA) shows great promise for achieving high accelerating gradients, perhaps >250 MV/m, for such machines as electron linear colliders. This paper presents the results of studies of candidate structures for a TBA. Also, the hardware and program for 35 GHz high-gradient testing are described. 18 refs., 13 figs.

  19. ACCELERATING AND COLLIDING POLARIZED PROTONS IN RHIC WITH SIBERIAN SNAKES.

    SciTech Connect

    ROSER,T.; AHRENS,L.; ALESSI,J.; BAI,M.; BEEBE - WANG,J.; BRENNAN,J.M.; BROWN,K.A.; BUNCE,G.; CAMERON,P.; COURANT,E.D.; DREES,A.; FISCHER,W.; ET AL

    2002-06-02

    We successfully injected polarized protons in both RHIC rings and maintained polarization during acceleration up to 100 GeV per ring using two Siberian snakes in each ring. Each snake consists of four helical superconducting dipoles which rotate the polarization by 180{sup o} about a horizontal axis. This is the first time that polarized protons have been accelerated to 100 GeV. We report on our experiences during commissioning and operation of collider with polarized protons.

  20. Proposal of the Next Incarnation of Accelerator Test Facility at KEK for the International Linear Collider

    SciTech Connect

    Araki, S.; Hayano, H.; Higashi, Y.; Honda, Y.; Kanazawa, K.; Kubo, K.; Kume, T.; Kuriki, M.; Kuroda, S.; Masuzawa, M.; Naito, T.; Okugi, T.; Sugahara, R.; Takahashi, T.; Tauchi, T.; Terunuma, N.; Toge, N.; Urakawa, J.; Vogel, V.; Yamaoka, H.; Yokoya, K.; /KEK, Tsukuba /Beijing, Inst. High Energy Phys. /Novosibirsk, IYF /Daresbury /CERN /Hiroshima U. /Orsay, LAL /LLNL, Livermore /North Carolina A-T State U. /Oxford U. /Pohang Accelerator Lab. /Queen Mary, U. of London /Royal Holloway, U. of London /DESY /SLAC /University Coll. London /Oregon U. /Tokyo U.

    2005-05-27

    To reach design luminosity, the International Linear Collider (ILC) must be able to create and reliably maintain nanometer size beams. The ATF damping ring is the unique facility where ILC emittances are possible. In this paper we present and evaluate the proposal to create a final focus facility at the ATF which, using compact final focus optics and an ILC-like bunch train, would be capable of achieving 37 nm beam size. Such a facility would enable the development of beam diagnostics and tuning methods, as well as the training of young accelerator physicists.

  1. Tests of the FONT3 Linear Collider Intra-Train Beam Feedback System at the ATF

    SciTech Connect

    Burrows, P.N.; Christian, G.; Clarke, C.; Hartin, A.; Dabiri Khah, H.; Molloy, S.; White, G.R.; Frisch, J.C.; Markiewicz, T.W.; McCormick, D.J.; Ross, M.C.; Smith, S.; Smith, T.J.; Kalinin, A.; Perry, C.; /Oxford Instruments

    2006-03-14

    We report preliminary results of beam tests of the FONT3 Linear Collider intra-train position feedback system prototype at the Accelerator Test Facility at KEK. The feedback system incorporates a novel beam position monitor (BPM) processor with a latency below 5 nanoseconds, and a kicker driver amplifier with similar low latency. The 56 nanosecond-long bunchtrain in the ATF extraction line was used to test the prototype BPM processor. The achieved latency will allow a demonstration of intra-train feedback on timescales relevant even for the CLIC Linear Collider design.

  2. Beam dump experiment at future electron-positron colliders

    NASA Astrophysics Data System (ADS)

    Kanemura, Shinya; Moroi, Takeo; Tanabe, Tomohiko

    2015-12-01

    We propose a new beam dump experiment at future colliders with electron (e-) and positron (e+) beams, BDee, which will provide a new possibility to search for hidden particles, like hidden photon. If a particle detector is installed behind the beam dump, it can detect the signal of in-flight decay of the hidden particles produced by the scatterings of e± beams off materials for dumping. We show that, compared to past experiments, BDee (in particular BDee at e+e- linear collider) significantly enlarges the parameter region where the signal of the hidden particle can be discovered.

  3. 62-TeV center of mass hadron collider with superbunch beams

    SciTech Connect

    Ryuji Yamada et al.

    2001-11-05

    The scheme of a 62-TeV center of mass p-p collider with superbunch beams at Fermilab is proposed as a practical and realistically achievable future project. It will be built in two stages, using the same tunnel, first with a 2 Tesla low field magnet collider ring and later with a 10 Tesla high field magnet collider ring. Both low and high field magnets have twin bore aperture and will be installed in the tunnel with the circumference of 87.25 km. In each bore a proton beam is accelerated, using induction cavities to increase luminosity. In the first stage they install a 7 TeV accelerator ring with operating field of 2 Tesla, based on the superferric transmission-line design. This ring will be operated at a 14-TeV center of mass collider. This will have the same energy as the LHC, but it will have 15 times higher luminosity, namely 1.5 x 10{sup 35}/cm{sup 2}/sec. The estimated synchrotron radiation is negligible with this machine. The existing Fermilab accelerator system, including the 150 GeV main injector, will be used as the injector system. Its rough cost estimation and schedule for this first stage are presented. In the second stage proton beams are accelerated, also using induction cavities up to 31 TeV with the 10 Tesla dipole magnets. The counter circulating beams will collide with the 62-TeV center of mass energy. With the superbunch beams they can expect the luminosity can be increased about 15 times more than the conventional method with RF cavities. It will be 10{sup 35}/cm{sup 2}/sec. In the second stage, the synchrotron radiation power will be about 12 W/m, and they need an elaborated beam screen.

  4. A Concept of Plasma Wake Field Acceleration Linear Collider (PWFA-LC)

    SciTech Connect

    Seryi, Andrei; Hogan, Mark; Pei, Shilun; Raubenheimer, Tor; Tenenbaum, Peter; Katsouleas, Tom; Huang, Chengkun; Joshi, Chan; Mori, Warren; Muggli, Patric; /Southern California U.

    2009-10-30

    Plasma Wake-Field Acceleration (PWFA) has demonstrated acceleration gradients above 50 GeV/m. Simulations have shown drive/witness bunch configurations that yield small energy spreads in the accelerated witness bunch and high energy transfer efficiency from the drive bunch to the witness bunch, ranging from 30% for a Gaussian drive bunch to 95% for a shaped longitudinal profile. These results open the opportunity for a linear collider that could be compact, efficient and more cost effective that the present microwave technologies. A concept of a PWFA-based Linear Collider (PWFA-LC) has been developed and is described in this paper. The drive beam generation and distribution, requirements on the plasma cells, and optimization of the interaction region parameters are described in detail. The R&D steps needed for further development of the concept are also outlined.

  5. Online calculation of the Tevatron collider luminosity using accelerator instrumentation

    SciTech Connect

    Hahn, A.A.

    1997-07-01

    The luminosity of a collision region may be calculated if one understands the lattice parameters and measures the beam intensities, the transverse and longitudinal emittances, and the individual proton and antiproton beam trajectories (space and time) through the collision region. This paper explores an attempt to make this calculation using beam instrumentation during Run 1b of the Tevatron. The instrumentation used is briefly described. The calculations and their uncertainties are compared to luminosities calculated independently by the Collider Experiments (CDF and D0).

  6. Summary Report of Working Group 5: Electron Beam Driven Plasma Accelerators

    SciTech Connect

    Hogan, Mark J.; Conde, Manoel E.

    2009-01-22

    Electron beam driven plasma accelerators have seen rapid progress over the last decade. Recent efforts have built on this success by constructing a concept for a plasma wakefield accelerator based linear collider. The needs for any future collider to deliver both energy and luminosity have substantial implications for interpreting current experiments and setting priorities for the future. This working group reviewed current experiments and ideas in the context of the demands of a future collider. The many discussions and presentations are summarized here.

  7. An MCNPX accelerator beam source

    SciTech Connect

    Durkee, Joe W.; Elson, Jay S.; Jason, Andrew; Johns, Russell C.; Waters, Laurie S.

    2009-06-04

    MCNPX is a powerful Monte Carlo code that can be used to conduct sophisticated radiation-transport simulations involving complex physics and geometry. Although MCNPX possesses a wide assortment of standardized modeling tools, there are instances in which a user's needs can eclipse existing code capabilities. Fortunately, although it may not be widely known, MCNPX can accommodate many customization needs. In this article, we demonstrate source-customization capability for a new SOURCE subroutine as part of our development to enable simulations involving accelerator beams for active-interrogation studies. Simulation results for a muon beam are presented to illustrate the new accelerator-source capability.

  8. Beam-Beam deflection as a beam tuning tool at the SLAC Linear Collider

    SciTech Connect

    Koska, W.; Bambade, P.; Kozanecki, W.; Phinney, N.; Wagner, S.R.

    1989-04-01

    To achieve maximum integrated luminosity at the SLAC Linear Collider, a method of noninvasive beam tuning is required. Traditional luminosity monitors based on Bhabha scattering are inadequate because of low instantaneous counting rates. Coherent deflections of one beam by the electromagnetic field of the other are sensitive not only to the relative steering of the two bunches but also to their spot sizes. A brief description of beam-beam deflection theory forms the basis for a discussion of this phenomenon as a tool for single-beam tuning and for luminosity optimization at the interaction point of the SLC. 13 refs., 5 figs.

  9. Linear accelerators for TeV colliders. Revision

    SciTech Connect

    Wilson, P.B.

    1985-10-01

    The basic scaling relations for important linear collider design parameters are introduced. Some of the basic concepts concerning the design of accelerating structures are presented, and breakdown limitations are discussed. Rf power sources are considered. Some of the key concepts of wakefield accelerators are discussed, and some examples of wake fields for typical linac structures are presented. Some general concepts concerning emittance, and the limitations on the emittance that can be obtained from linac guns and damping rings are discussed. 49 refs., 15 figs. (LEW)

  10. Effect of 3D Polarization profiles on polarization measurements and colliding beam experiments

    SciTech Connect

    Fischer, W.; Bazilevsky, A.

    2011-08-18

    The development of polarization profiles are the primary reason for the loss of average polarization. Polarization profiles have been parametrized with a Gaussian distribution. We derive the effect of 3-dimensional polarization profiles on the measured polarization in polarimeters, as well as the observed polarization and the figure of merit in single and double spin experiments. Examples from RHIC are provided. The Relativistic Heavy Ion Collider (RHIC) is the only collider of spin polarized protons. During beam acceleration and storage profiles of the polarization P develop, which affect the polarization measured in a polarimeter, and the polarization and figure of merit (FOM) in colliding beam experiments. We calculate these for profiles in all dimensions, and give examples for RHIC. Like in RHIC we call the two colliding beams Blue and Yellow. We use the overbar to designate intensity-weighted averages in polarimeters (e.g. {bar P}), and angle brackets to designate luminosity-weighted averages in colliding beam experiments (e.g.

    ).

  11. Toward design of the Collider Beam Collimation System

    SciTech Connect

    Drozhdin, A.; Mokhov, N.; Soundranayagam, R.; Tompkins, J.

    1994-02-01

    A multi-component beam collimation system for the Superconducting Super Collider is described. System choice justification and design requirements are presented. System consists of targets, scrapers, and collimators with appropriate cooling and radiation shielding. Each component has an independent control for positioning and aligning with respect to the beam. Results of beam loss distribution, energy deposition calculations, and thermal analyses, as well as cost estimate, are presented.

  12. Design and construction of vacuum systems for large colliders using superconducting magnets

    SciTech Connect

    Halama, H.J.

    1983-01-01

    Vacuum system requirements for proton accelerators and colliders with superconducting megnets are discussed. The vacuum systems for the colliding beam accelerator and the Tevatron are described. (WHK)

  13. High Gradient Two-Beam Electron Accelerator

    SciTech Connect

    Jiang, Y.; Kazakov, S. Yu.; Kuzikov, S. V.; Hirshfield, J. L.

    2010-11-04

    A high-gradient two-beam electron accelerator structure using detuned cavities is described. A self-consistent theory based on a circuit model is presented to calculate idealized acceleration gradient, transformer ratio, and efficiency for energy transfer from the drive beam to the accelerated beam. Experimental efforts are being carried out to demonstrate this acceleration concept.

  14. First demonstration of optics measurement and correction during acceleration with beta-squeeze in a high energy collider

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

    Setting up collisions in high energy circular colliders requires beam acceleration and "beta-squeeze". The latter produces small beam sizes, and hence, high luminosity by applying strong focusing with quadrupoles near the interaction points. At the Relativistic Heavy Ion Collider (RHIC), these two processes, beam acceleration and beta-squeeze, have been performed simultaneously during recent years. In the past, beam optics correction at RHIC has only taken place at injection and at final energy, with interpolation of corrections partially into the acceleration cycle. Recent measurements of the beam optics during acceleration and squeeze have evidenced significant beta-beats that, if corrected, could minimize undesirable emittance dilutions and maximize the spin polarization of polarized proton beams by avoiding the high-order multipole fields sampled by particles within the bunch. We recently demonstrated beam optics corrections during acceleration at RHIC. As a valuable by-product, these corrections minimized the beta-beat at the profile monitors, so providing more accurate measurements of the evolution of the beam emittances during acceleration.

  15. Fundamental beam-beam limit from head-on interaction in the Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    Ohmi, Kazuhito; Zimmermann, Frank

    2015-12-01

    The beam-beam limit at hadron colliders manifests itself in the form of degraded luminosity lifetime and/or reduced beam lifetime. In particular, for increasing beam intensity, the nonlinear beam-beam force causes incoherent emittance growth, while the (linear) coupling force between the two colliding beams can result in coherent beam-beam instabilities. These phenomena may be enhanced (or suppressed) by lattice errors, external noise, and other perturbations. We investigate the luminosity degradation caused both by incoherent emittance growth and by coherent beam-beam instability. The resulting beam-beam limit for an ideal machine and the of question how it is affected by some of the aforementioned errors are discussed in theory and simulation.

  16. Proton Beams from Nanotube Accelerator

    NASA Astrophysics Data System (ADS)

    Murakami, Masakatsu; Tanaka, Motohiko

    2013-10-01

    A carbon nanotube (CNT) is known to have extraordinary material and mechanical properties. Here we propose a novel ion acceleration scheme with nanometer-size CNT working at such an extreme circumstance as temperatures higher than billions of degree and durations shorter than tens of femtosecond, dubbed as nanotube accelerator, with which quasimonoenergetic and collimated MeV-order proton beams are generated. In nanotube accelerators, CNTs with fragments of a hydrogen compound embedded inside are irradiated by an ultrashort ultraintense laser. Under such laser and target conditions, low-Z materials such as hydrogen and carbon will be fully ionized. Substantial amount of electrons of the system are then blown off by the brutal laser electric field within only a few laser cycles. This leads to a new type of ion acceleration, in which the nanotube and embedded materials play the roles of a gun barrel and bullets, respectively, to produce highly collimated and quasimonoenergetic proton beams. Three-dimensional particle simulations, that take all the two-body Coulomb interactions into account, demonstrate generation of quasimonoenergetic 1.5-MeV proton beams under a super-intense electrostatic field ~ 1014 V m-1.

  17. Advances in Beam Cooling for Muon Colliders

    SciTech Connect

    R.P. Johnson, Y.S. Derbenev

    2006-09-01

    A six-dimensional (6D) ionization cooling channel based on helical magnets surrounding RF cavities filled with dense hydrogen gas is the basis for the latest plans for muon colliders. This helical cooling channel (HCC) has solenoidal, helical dipole, and helical quadrupole magnetic fields, where emittance exchange is achieved by using a continuous homogeneous absorber. Momentum-dependent path length differences in the dense hydrogen energy absorber provide the required correlation between momentum and ionization loss to accomplish longitudinal cooling. Recent studies of an 800 MHz RF cavity pressurized with hydrogen, as would be used in this application, show that the maximum gradient is not limited by a large external magnetic field, unlike vacuum cavities. Two new cooling ideas, Parametric-resonance Ionization Cooling and Reverse Emittance Exchange, will be employed to further reduce transverse emittances to a few mm-mr, which allows high luminosity with fewer muons than previously imagined. We describe these new ideas as well as a new precooling idea based on a HCC with z dependent fields that is being developed for an exceptional 6D cooling demonstration experiment. The status of the designs, simulations, and tests of the cooling components for a high luminosity, low emittance muon collider will be reviewed.

  18. Accelerator dynamics and beam aperture

    SciTech Connect

    Parsa, Z.

    1986-10-01

    We present an analytical method for analyzing accelerator dynamics, including higher order effects of multipoles on the beam. This formalism provides a faster alternative to particle tracking. Simplectic expressions for the emittance and phase describing the dynamical behavior of a particle in a circular accelerator are derived using second order perturbation theory (in the presence of nonlinear elements, e.g., sextupoles, octupoles). These expressions are successfully used to calculate the emittance growth, smear and linear aperture. Our findings compare well with results obtained from tracking programs. In addition perturbation to betatron tune; resonance strengths; stop bandwidth; fixed points; island width; and Chirikov criteria are calculated.

  19. Effect of Beam-Beam Interactions on Stability of Coherent Oscillations in a Muon Collider

    SciTech Connect

    Alexahin, Y.; Ohmi, K.; /KEK, Tsukuba

    2012-05-01

    In order to achieve peak luminosity of a muon collider in the 10{sup 34}/cm{sup 2}/s range the number of muons per bunch should be of the order of a few units of 10{sup 12} rendering the beam-beam parameter as high as 0.1 per IP. Such strong beam-beam interaction can be a source of instability if the working point is chosen close to a coherent beam-beam resonance. On the other hand, the beam-beam tunespread can provide a mechanism of suppression of the beam-wall driven instabilities. In this report the coherent instabilities driven by beam-beam and beam-wall interactions are studied with the help of BBSS code for the case of 1.5 TeV c.o.m muon collider.

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

    NASA Astrophysics Data System (ADS)

    Lidia, Steven Michael

    Two-beam accelerators (TBAs) based upon free-electron lasers (FELs) or relativistic klystrons (RK-TBAs) have been proposed as efficient power sources for next generation high-energy linear colliders. Studies have demonstrated the possibility of building TBAs from X-band (~8-12 GHz) through Ka-band (~30-35 GHz) frequency regions. A new method of simulating the beam dynamics in accelerators of this type has been developed in this dissertation. There are three main components to this simulation. The first is a tracking algorithm to generate nonlinear transfer maps for pushing noninteracting particles through the external fields. A mapping algorithm is used so that tens or hundreds of thousands of macroparticles can be pushed from the solution of a few hundreds of differential equations. This is a great cost-savings device from the standpoint of CPU cycles. It can increase by several orders of magnitude the number of macroparticles that take place in the simulation, enabling more accurate modeling of the evolution of the beam distribution and enhanced sensitivity to effects due to the beam's halo. The second component is a 3D Particle-In-Cell (PIC) algorithm that solves a set of Helmholtz equations for the self-fields, including the conducting boundary condition, and generates impulses that are interleaved with the nonlinear maps by means of a split- operator algorithm. The Helmholtz equations are solved by a multi-grid algorithm. The third component is an equivalent circuit equation solver that advances the modal rf cavity fields in time due to excitation by the modulated beam. The beam-cavity interaction is analyzed and divided naturally into two distinct times scales. The RTA project is described, and the simulation code is used to design the latter portions of the experiment. Detailed calculations of the beam dynamics and of the rf cavity output are presented and discussed. A beamline design is presented that will generate nearly 1.2 TW of power from 40 input, gain, and output rf cavities over a 10 m distance. The simulations show that beam current losses are acceptable, and that longitudinal and transverse focusing techniques are sufficiently capable of maintaining a high degree of beam quality along the entire beamline. Additional experimental efforts are described. The first is the commissioning of the RTA injector. This electron gun produces a 1 MV, 600 A beam over a 250 ns pulse length. The post-injector beamline is described, and the battery of diagnostics is presented, with initial results reported. (Abstract shortened by UMI.)

  1. International X-Band Linear Collider Accelerator Structure R&D

    SciTech Connect

    Wang, J.W.; /SLAC

    2009-03-04

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

  2. Wakefield Damping in a Pair of X-Band Accelerators for Linear Colliders

    SciTech Connect

    Jones, R.M.; Adolphsen, C.E.; Wang, J.W.; Li, Z.; /SLAC

    2006-12-18

    We consider means to damp the wake-field left behind ultra-relativistic charges. In particular, we focus on a pair of travelling wave accelerators operating at an X-band frequency of 11.424 GHz. In order to maximize the efficiency of acceleration, in the context of a linear collider, multiple bunches of charged particles are accelerated within a given pulse of the electromagnetic field. The wake-field left behind successive bunches, if left unchecked, can seriously disturb the progress of trailing bunches and can lead to an appreciable dilution in the emittance of the beam. We report on a method to minimize the influence of the wake-field on trailing bunches. This method entails detuning the characteristic mode frequencies which make-up the electromagnetic field, damping the wake-field, and interleaving the frequencies of adjacent accelerating structures. Theoretical predictions of the wake-field and modes, based on a circuit model, are compared with experimental measurements of the wake-field conducted within the ASSET facility at SLAC. Very good agreement is obtained between theory and experiment and this allows us to have some confidence in designing the damping of wake-fields in a future linear collider consisting of several thousand of these accelerating structures.

  3. Degradation of multibunch luminosity in a linear collider due to cumulative beam breakup

    SciTech Connect

    Courtlandt L. Bohn; Michael J. Syphers; Daniel Schulte

    2001-06-26

    Beam-excited transverse wakes in accelerating radiofrequency structures will influence the transverse offsets of each bunch in a multibunch train, causing the projected emittance of the bunch train to grow. An analytic theory of this phenomenon that includes the mitigating influence of a correlated energy spread across the bunch train was recently devised and applied to electron-positron linear colliders. We use the results of this theory to estimate analytically the associated degradation of multibunch luminosity in terms of top-level parameters for the two beams, the two accelerators, and the final-focus system. Then we compare the estimates with results from GUINEA-PIG, a code that includes the detailed physics of beam-beam interactions.

  4. Approaches to Beam Stabilization in X-Band Linear Colliders

    SciTech Connect

    Frisch, Josef; Hendrickson, Linda; Himel, Thomas; Markiewicz, Thomas; Raubenheimer, Tor; Seryi, Andrei; Burrow, Philip; Molloy, Stephen; White, Glen; /Queen Mary U. of London

    2006-09-05

    In order to stabilize the beams at the interaction point, the X-band linear collider proposes to use a combination of techniques: inter-train and intra-train beam-beam feedback, passive vibration isolation, and active vibration stabilization based on either accelerometers or laser interferometers. These systems operate in a technologically redundant fashion: simulations indicate that if one technique proves unusable in the final machine, the others will still support adequate luminosity. Experiments underway for all of these technologies have already demonstrated adequate performance.

  5. Theory and suppression of multibunch beam breakup in linear colliders

    SciTech Connect

    Courtlandt L. Bohn and King-Yuen Ng

    2000-08-08

    The authors recently developed an analytic theory of cumulative multibunch beam breakup that includes a linear variation of transverse focusing across the bunch train. The focusing variation saturates the exponential growth of the beam breakup and establishes an algebraic decay of the transverse bunch displacement versus bunch number. In this paper they illustrate how the focusing variation works to suppress multibunch beam breakup, as well as how the mechanism scales with accelerator and beam parameters.

  6. On the Possibility of a Plasma Afterburner -- a 100 GeV Collider based on Plasma Wakefield Acceleration

    NASA Astrophysics Data System (ADS)

    Katsouleas, Tom; Lee, Seung; Joshi, Chan; Mori, W. B.; Clayton, Chris; Dodd, Evan; Dawson, John

    2000-10-01

    The possible use of short plasma sections at the end of an existing high energy particle collider (afterburners) such as the Stanford Linear Collider in order to boost the energy of the collider is explored. The electron and positron beams in the collider are divided into two bunches each. The first bunch in each arm of the collider excites a large amplitude plasma wake that accelerates the second bunch at rates of order 10 GeV/m over a few meters. The luminosity of the collider is maintained by reducing the spot size at the collision point with plasma lens sections just before the collision. Designs for a possible Afterburner to boost the physics reach of the SLC from 50 GeV to over 100 GeV are presented. Detailed particle-in-cell simulations are presented. Critical issues for realizing this idea are discussed including beam loading, energy spread, beam matching and emittance growth, plasma source development and hose instabilities.

  7. Development of a CVD diamond Beam Condition Monitor for CMS at the Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    Fernandez-Hernando, L.; Chong, D.; Gray, R.; Ilgner, C.; Macpherson, A.; Oh, A.; Pritchard, T.; Stone, R.; Worm, S.

    2005-10-01

    The CERN Large Hadron Collider (LHC) will store 2808 bunches per colliding beam, with each bunch consisting of 10 11 protons at an energy of 7 TeV. If there is a failure in an element of the accelerator, the resulting beam losses could cause damage not only to the machine but also to the experiments. A Beam Condition Monitor (BCM) is foreseen to monitor fast increments of particle fluxes near the interaction point and, if necessary, to generate an abort signal to the LHC accelerator control to dump the beams. The system is being developed initially for the CMS experiment but it is sufficiently general to find potential applications elsewhere. Due to its high radiation hardness, CVD diamond was chosen for investigation as the BCM sensor. Various samples of CVD diamond have been characterized extensively with both a 90Sr source and in high-intensity test beams in order to assess the capabilities of such sensors and to study whether this detector technology is suitable for a BCM system. A selection of results from these investigations is presented.

  8. Particle dynamics and its consequences in wakefield acceleration in a high energy collider

    SciTech Connect

    Cheshkov, S.; Tajima, T.; Horton, W.; Yokoya, K.

    1998-09-01

    The performance of a wakefield accelerator in a high energy collider application is analyzed by use of a nonlinear dynamics map built on a simple theoretical model of the wakefield generated by the laser pulse (or whatever other method) and a code based on this map. The crucial figures of merit for such a system other than the final energy include the emittance (that determines the luminosity). The more complex the system is, the more opportunities the system has to degrade the emittance (or entropy of the beam). This the map guides one to identify where the crucial elements lie that affect the emittance. If the focusing force of the wakefield is strong when there is a jitter in the position (or laser aiming) of each stage coupled with the spread in the individual particle betatron frequencies, particles experience a phase space mixing. This effect sensitively controls the emittance degradation. They investigate these effects both in a uniform plasma and in a plasma channel. They also study the effect of beam loading. Further, they briefly consider collision point physics issues for a collider expected or characteristic of such a construction based on a scenario for the multi-staged wakefield accelerators.

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

    DOEpatents

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

    1984-03-22

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

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

    DOEpatents

    Birx, Daniel L. (Brentwood, CA); Reginato, Louis L. (Orinda, CA)

    1988-01-01

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

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

    DOEpatents

    Birx, Daniel L. (Brentwood, CA); Reginato, Louis L. (Orinda, CA)

    1987-01-01

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

  12. Beam tube vacuum in future superconducting proton colliders

    SciTech Connect

    Turner, W.

    1994-10-01

    The beam tube vacuum requirements in future superconducting proton colliders that have been proposed or discussed in the literature -- SSC, LHC, and ELN -- are reviewed. The main beam tube vacuum problem encountered in these machines is how to deal with the magnitude of gas desorption and power deposition by synchrotron radiation while satisfying resistivity, impedance, and space constraints in the cryogenic environment of superconducting magnets. A beam tube vacuum model is developed that treats photodesorption of tightly bound H, C, and 0, photodesorption of physisorbed molecules, and the isotherm vapor pressure of H{sub 2}. Experimental data on cold tube photodesorption experiments are reviewed and applied to model calculations of beam tube vacuum performance for simple cold beam tube and liner configurations. Particular emphasis is placed on the modeling and interpretation of beam tube photodesorpiion experiments at electron synchrotron light sources. The paper also includes discussion of the constraints imposed by beam image current heating, the growth rate of the resistive wall instability, and single-bunch instability impedance limits.

  13. Beam tube vacuum in future superconducting proton colliders

    NASA Astrophysics Data System (ADS)

    Turner, William C.

    1995-02-01

    The beam tube vacuum requirements in future superconducting proton colliders that have been proposed or discussed in the literatureSSC, LHC, and ELNare reviewed. The main beam tube vacuum problem encountered in these machines is how to deal with the magnitude of gas desorption and power deposition by synchrotron radiation while satisfying resistivity, impedance, and space constraints in the cryogenic environment of superconducting magnets. A beam tube vacuum model is developed that treats photodesorption of tightly bound H, C, and O, photodesorption of physisorbed molecules, and the isotherm vapor pressure of H2. Experimental data on cold tube photodesorption experiments are reviewed and applied to model calculations of beam tube vacuum performance for simple cold beam tube and liner configurations. Particular emphasis is placed on the modeling and interpretation of beam tube photodesorption experiments at electron synchrotron light sources. The paper also includes discussion of the constraints imposed by beam image current heating, the growth rate of the resistive wall instability, and single-bunch instability impedance limits.

  14. Thermomechanical response of Large Hadron Collider collimators to proton and ion beam impacts

    NASA Astrophysics Data System (ADS)

    Cauchi, Marija; Assmann, R. W.; Bertarelli, A.; Carra, F.; Cerutti, F.; Lari, L.; Redaelli, S.; Mollicone, P.; Sammut, N.

    2015-04-01

    The CERN Large Hadron Collider (LHC) is designed to accelerate and bring into collision high-energy protons as well as heavy ions. Accidents involving direct beam impacts on collimators can happen in both cases. The LHC collimation system is designed to handle the demanding requirements of high-intensity proton beams. Although proton beams have 100 times higher beam power than the nominal LHC lead ion beams, specific problems might arise in case of ion losses due to different particle-collimator interaction mechanisms when compared to protons. This paper investigates and compares direct ion and proton beam impacts on collimators, in particular tertiary collimators (TCTs), made of the tungsten heavy alloy INERMET 180. Recent measurements of the mechanical behavior of this alloy under static and dynamic loading conditions at different temperatures have been done and used for realistic estimates of the collimator response to beam impact. Using these new measurements, a numerical finite element method (FEM) approach is presented in this paper. Sequential fast-transient thermostructural analyses are performed in the elastic-plastic domain in order to evaluate and compare the thermomechanical response of TCTs in case of critical beam load cases involving proton and heavy ion beam impacts.

  15. Radio Frequency Noise Effects on the CERN Large Hadron Collider Beam Diffusion

    SciTech Connect

    Mastoridis, T.; Baudrenghien, P.; Butterworth, A.; Molendijk, J.; Rivetta, C.; Fox, J.D.; /SLAC

    2012-04-30

    Radio frequency (rf) accelerating system noise can have a detrimental impact on the Large Hadron Collider (LHC) performance through longitudinal motion and longitudinal emittance growth. A theoretical formalism has been developed to relate the beam and rf station dynamics with the bunch length growth. Measurements were conducted at LHC to determine the performance limiting rf components and validate the formalism through studies of the beam diffusion dependence on rf noise. As a result, a noise threshold was established for acceptable performance which provides the foundation for beam diffusion estimates for higher energies and intensities. Measurements were also conducted to determine the low level rf noise spectrum and its major contributions, as well as to validate models and simulations of this system.

  16. Heavy ion beam loss mechanisms at an electron-ion collider

    NASA Astrophysics Data System (ADS)

    Klein, Spencer R.

    2014-12-01

    There are currently several proposals to build a high-luminosity electron-ion collider, to study the spin structure of matter and measure parton densities in heavy nuclei, and to search for gluon saturation and new phenomena like the colored glass condensate. These measurements require operation with heavy nuclei. We calculate the cross sections for two important processes that will affect accelerator and detector operations: bound-free pair production and Coulomb excitation of the nuclei. Both of these reactions have large cross sections, 28-56 mb, which can lead to beam ion losses, produce beams of particles with altered charge:mass ratio, and produce a large flux of neutrons in zero degree calorimeters. The loss of beam particles limits the sustainable electron-ion luminosity to levels of several times 1032/cm2/s .

  17. To study the emittance dilution in Superconducting Linear Accelerator Design for International Linear Collider (ILC)

    NASA Astrophysics Data System (ADS)

    Ranjan, Kirti; Solyak, Nikolay; Tenenbaum, Peter

    2005-04-01

    Recently the particle physics community has chosen a single technology for the new accelerator, opening the way for the world community to unite and concentrate resources on the design of an International Linear collider (ILC) using superconducting technology. One of the key operational issues in the design of the ILC will be the preservation of the small beam emittances during passage through the main linear accelerator (linac). Sources of emittance dilution include incoherent misalignments of the quadrupole magnets and rf-structure misalignments. In this work, the study of emittance dilution for the 500-GeV center of mass energy main linac of the Superconducting Linear Accelerator design, based on adaptation of the TESLA TDR design is performed using LIAR simulation program. Based on the tolerances of the present design, effect of two important Beam-Based steering algorithms, Flat Steering and Dispersion Free Steering, are compared with respect to the emittance dilution in the main linac. We also investigated the effect of various misalignments on the emittance dilution for these two steering algorithms.

  18. Simulation Studies of Beam-Beam Effects of a Ring-Ring Electron-Ion Collider Based on CEBAF

    SciTech Connect

    Yuhong Zhang,Ji Qiang

    2009-05-01

    The collective beam-beam effect can potentially cause a rapid growth of beam sizes and reduce the luminosity of a collider to an unacceptably low level. The ELIC, a proposed ultra high luminosity electron-ion collider based on CEBAF, employs high repetition rate crab crossing colliding beams with very small bunch transverse sizes and very short bunch lengths, and collides them at up to 4 interaction points with strong final focusing. All of these features can make the beam-beam effect challenging. In this paper, we present simulation studies of the beam-beam effect in ELIC using a self-consistent strong-strong beam-beam simulation code developed at Lawrence Berkeley National Laboratory. This simulation study is used for validating the ELIC design and for searching for an optimal parameter set.

  19. Review of linear collider beam-beam interaction

    SciTech Connect

    Chen, P.

    1989-01-01

    Three major effects from the interaction of e/sup +/e/sup /minus// beams---disruption, beamstrahlung, and electron-positron pair creation---are reviewed. For the disruption effects we discuss the luminosity enhancement factor, the maximum and rms disruption angles, and the ''kink instability''. All the results are obtained from computer simulations. Scaling laws for the numerical results and theoretical explanations of the computer acquired phenomena are offered wherever possible. For the beamstrahlung effects we concentrate only on the final electron energy spectrum resulting from multiple photon radiation process, and the deflection angle associated with low energy particles. For the effects from electron-positron pair creation, both coherent and incoherent processes of beamstrahlung pair creation are discussed. In addition to the estimation on total number of such pairs, we also look into the energy spectrum and the deflection angle. 17 refs., 23 figs., 1 tab.

  20. Ion colliders

    SciTech Connect

    Fischer, W.

    2011-12-01

    Ion colliders are research tools for high-energy nuclear physics, and are used to test the theory of Quantum Chromo Dynamics (QCD). The collisions of fully stripped high-energy ions create matter of a temperature and density that existed only microseconds after the Big Bang. Ion colliders can reach higher densities and temperatures than fixed target experiments although at a much lower luminosity. The first ion collider was the CERN Intersecting Storage Ring (ISR), which collided light ions [77Asb1, 81Bou1]. The BNL Relativistic Heavy Ion Collider (RHIC) is in operation since 2000 and has collided a number of species at numerous energies. The CERN Large Hadron Collider (LHC) started the heavy ion program in 2010. Table 1 shows all previous and the currently planned running modes for ISR, RHIC, and LHC. All three machines also collide protons, which are spin-polarized in RHIC. Ion colliders differ from proton or antiproton colliders in a number of ways: the preparation of the ions in the source and the pre-injector chain is limited by other effects than for protons; frequent changes in the collision energy and particle species, including asymmetric species, are typical; and the interaction of ions with each other and accelerator components is different from protons, which has implications for collision products, collimation, the beam dump, and intercepting instrumentation devices such a profile monitors. In the preparation for the collider use the charge state Z of the ions is successively increased to minimize the effects of space charge, intrabeam scattering (IBS), charge change effects (electron capture and stripping), and ion-impact desorption after beam loss. Low charge states reduce space charge, intrabeam scattering, and electron capture effects. High charge states reduce electron stripping, and make bending and acceleration more effective. Electron stripping at higher energies is generally more efficient. Table 2 shows the charge states and energies in the RHIC and LHC injector chains for the heaviest ion species used to date. The RHIC pulsed sputter source (PSC) and Tandem electrostatic accelerator are being replaced by an Electron Beam Ion Source (EBIS), Radio Frequency Quadrupole (RFQ) and short linac [08Ale1]. With EBIS beams of any element can be prepared for RHIC including uranium and spin-polarized 3He. At CERN an ECR ion source is used, followed by an RFQ and Linac. The ions are then accumulated, electron cooled, and accelerated in LEIR. After transfer to and acceleration in the PS, ion beams are injected into the SPS.

  1. ELECTRON BEAM STABILITY REQUIREMENTS FOR LINAC-RING ELECTRON-ION COLLIDERS.

    SciTech Connect

    MONTAG, C.

    2005-05-16

    In recent years, linac-ring electron-ion colliders have been proposed at a number of laboratories around the world. While the linac-ring approach overcomes the beam-beam tuneshift limitation on the electron beam, it also introduces noise into the ion beam, via the beam-beam interaction with electron bunches of slightly fluctuating intensity and transverse size. The effect of these fluctuations is studied using a linearized model of the beam-beam interaction. Upper limits for the rms jitter amplitudes of electron beam parameters for various linac-ring electron-ion colliders are presented.

  2. Simulations and measurements of beam loss patterns at the CERN Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    Bruce, R.; Assmann, R. W.; Boccone, V.; Bracco, C.; Brugger, M.; Cauchi, M.; Cerutti, F.; Deboy, D.; Ferrari, A.; Lari, L.; Marsili, A.; Mereghetti, A.; Mirarchi, D.; Quaranta, E.; Redaelli, S.; Robert-Demolaize, G.; Rossi, A.; Salvachua, B.; Skordis, E.; Tambasco, C.; Valentino, G.; Weiler, T.; Vlachoudis, V.; Wollmann, D.

    2014-08-01

    The CERN Large Hadron Collider (LHC) is designed to collide proton beams of unprecedented energy, in order to extend the frontiers of high-energy particle physics. During the first very successful running period in 2010-2013, the LHC was routinely storing protons at 3.5-4 TeV with a total beam energy of up to 146 MJ, and even higher stored energies are foreseen in the future. This puts extraordinary demands on the control of beam losses. An uncontrolled loss of even a tiny fraction of the beam could cause a superconducting magnet to undergo a transition into a normal-conducting state, or in the worst case cause material damage. Hence a multistage collimation system has been installed in order to safely intercept high-amplitude beam protons before they are lost elsewhere. To guarantee adequate protection from the collimators, a detailed theoretical understanding is needed. This article presents results of numerical simulations of the distribution of beam losses around the LHC that have leaked out of the collimation system. The studies include tracking of protons through the fields of more than 5000 magnets in the 27 km LHC ring over hundreds of revolutions, and Monte Carlo simulations of particle-matter interactions both in collimators and machine elements being hit by escaping particles. The simulation results agree typically within a factor 2 with measurements of beam loss distributions from the previous LHC run. Considering the complex simulation, which must account for a very large number of unknown imperfections, and in view of the total losses around the ring spanning over 7 orders of magnitude, we consider this an excellent agreement. Our results give confidence in the simulation tools, which are used also for the design of future accelerators.

  3. Beam Breakup Effects in Dielectric Based Accelerators

    SciTech Connect

    Schoessow, P.; Kanareykin, A.; Jing, C.; Kustov, A.; Altmark, A.; Power, J. G.; Gai, W.

    2009-01-22

    The dynamics of the beam in structure-based wakefield accelerators leads to beam stability issues not ordinarily found in other machines. In particular, the high current drive beam in an efficient wakefield accelerator loses a large fraction of its energy in the decelerator structure, resulting in physical emittance growth, increased energy spread, and the possibility of head-tail instability for an off axis beam, all of which can lead to severe reduction of beam intensity. Beam breakup (BBU) effects resulting from parasitic wakefields provide a potentially serious limitation to the performance of dielectric structure based wakefield accelerators as well. We report on experimental and numerical investigation of BBU and its mitigation. The experimental program focuses on BBU measurements at the AWA facility in a number of high gradient and high transformer ratio wakefield devices. New pickup-based beam diagnostics will provide methods for studying parasitic wakefields that are currently unavailable. The numerical part of this research is based on a particle-Green's function beam breakup code we are developing that allows rapid, efficient simulation of beam breakup effects in advanced linear accelerators. The goal of this work is to be able to compare the results of detailed experimental measurements with the accurate numerical results and to design an external FODO channel for the control of the beam in the presence of strong transverse wakefields.

  4. Self-accelerating beams in photonic crystals.

    PubMed

    Kaminer, Ido; Nemirovsky, Jonathan; Makris, Konstantinos G; Segev, Mordechai

    2013-04-01

    We find accelerating beams in a general periodic optical system, such as photonic crystal slabs, honeycomb lattices, and various metamaterials. These beams retain a shape-preserving profile while bending to highly non-paraxial angles along a circular-like trajectory. The properties of such beams depend on the crystal lattice structure: on a small-scale, the fine features of the beams profile are uniquely derived from the exact structure of the crystalline cells, while on a large-scale the beam only depends on the periodicity of the lattice, asymptotically reaching the free-space analytic solutions when the wavelength is much larger than the cell size. We demonstrate such beams in a 2D Kronig-Penney separable model, but our methodology of finding such solutions is general, predicting accelerating beams in any periodic structure. This highlights how light can be guided through a general system by only tailoring the incoming field, without altering the structure itself. PMID:23571979

  5. Research and Development of Future Muon Collider

    SciTech Connect

    Yonehara, K.; /Fermilab

    2012-05-01

    Muon collider is a considerable candidate of the next generation high-energy lepton collider machine. A novel accelerator technology must be developed to overcome several intrinsic issues of muon acceleration. Recent research and development of critical beam elements for a muon accelerator, especially muon beam phase space ionization cooling channel, are reviewed in this paper.

  6. High Energy Colliding Beams; What Is Their Future?

    NASA Astrophysics Data System (ADS)

    Richter, Burton

    2015-02-01

    The success of the first few years of LHC operations at CERN, and the expectation of more to come as the LHC's performance improves, are already leading to discussions of what should be next for both proton-proton and electron-positron colliders. In this discussion I see too much theoretical desperation caused by the so-far-unsuccessful hunt for what is beyond the Standard Model, and too little of the necessary interaction of the accelerator, experimenter, and theory communities necessary for a scientific and engineering success. Here, I give my impressions of the problem, its possible solution, and what is needed to have both a scientifically productive and financially viable future.

  7. High Energy Colliding Beams; What Is Their Future?

    NASA Astrophysics Data System (ADS)

    Richter, Burton

    The success of the first few years of LHC operations at CERN, and the expectation of more to come as the LHC's performance improves, are already leading to discussions of what should be next for both proton-proton and electron-positron colliders. In this discussion I see too much theoretical desperation caused by the so-far-unsuccessful hunt for what is beyond the Standard Model, and too little of the necessary interaction of the accelerator, experimenter, and theory communities necessary for a scientific and engineering success. Here, I give my impressions of the problem, its possible solution, and what is needed to have both a scientifically productive and financially viable future.

  8. Accelerating beams with non-parabolic trajectories

    NASA Astrophysics Data System (ADS)

    Yan, Shaohui; Li, Manman; Yao, Baoli; Lei, Ming; Yu, Xianghua; Qian, Jia; Gao, Peng

    2014-03-01

    We present a family of one-dimensional accelerating beams in the paraxial limit whose trajectory is described, in normalized coordinates (?, s), by a non-parabolic curve ? = ?(s) with ?(s) denoting the transverse shift of beams. When taking different values of the parameters appearing in ?(s), three types of accelerating beams are observed. The first type accelerates initially along X direction and almost stops accelerating after traveling a large distance. The second type is seen to travel along a straight line with an angle with respect to the Z-axis at large distance. The beam of the last type is seen to leave initially upward and cross the Z-axis downward after traveling some distance.

  9. Photodesorption experiments on SSC collider beam tube configurations

    SciTech Connect

    Maslennikov, I.; Turner, W.; Anashin, V.; Malyshev, O.; Osipov, V.; Nazmov, V.; Pindyurin, V.; Salimov, A.; Foerster, C.; Lanni, C.

    1993-05-01

    Experimental measurements of photodesorption coefficients of H{sub 2}, CH{sub 4}, CO and CO{sub 2} are being done to obtain data necessary to predict the vacuum performance of the Collider. Experiments have been done or are planned for warm tubes (i.e. room temperature), cold tubes (i.e. 4.2 K) and liner configurations (i.e. 4.2 K, 20 K and 80 K). Two synchrotron radiation beamlines have been constructed on the VEPP-2M storage ring at BINP, Russia. The photon critical energy is 284 eV, as in the SSC Collider, angle of incidence is 10 mrad. To date approximately fifteen warm beam tubes have been tested, including elecrodeposited Cu, high purity bulk Cu and Nitronic 40 SS, several cleaning procedures, with and without in-situ baking and with and without magnetic field. The maximum integrated photon dose was achieved was 2{center_dot}10{sup 22} photons/m on the high intensity beamline. Several experiments have been done on the VUV ring at BNL to check a subset of the BINP data and to extend the integrated photon flux up to 10{sup 23} photons/m, or 100 days of SSC operation. The data from the warm experiments will be used to evaluate the best tubes to be used in the more time consuming cold experiments.

  10. Photodesorption experiments on SSC collider beam tube configurations

    SciTech Connect

    Maslennikov, I.; Turner, W. ); Anashin, V.; Malyshev, O.; Osipov, V.; Nazmov, V.; Pindyurin, V.; Salimov, A. . Inst. Yadernoj Fiziki); Foerster, C.; Lanni, C. )

    1993-05-01

    Experimental measurements of photodesorption coefficients of H[sub 2], CH[sub 4], CO and CO[sub 2] are being done to obtain data necessary to predict the vacuum performance of the Collider. Experiments have been done or are planned for warm tubes (i.e. room temperature), cold tubes (i.e. 4.2 K) and liner configurations (i.e. 4.2 K, 20 K and 80 K). Two synchrotron radiation beamlines have been constructed on the VEPP-2M storage ring at BINP, Russia. The photon critical energy is 284 eV, as in the SSC Collider, angle of incidence is 10 mrad. To date approximately fifteen warm beam tubes have been tested, including elecrodeposited Cu, high purity bulk Cu and Nitronic 40 SS, several cleaning procedures, with and without in-situ baking and with and without magnetic field. The maximum integrated photon dose was achieved was 2[center dot]10[sup 22] photons/m on the high intensity beamline. Several experiments have been done on the VUV ring at BNL to check a subset of the BINP data and to extend the integrated photon flux up to 10[sup 23] photons/m, or 100 days of SSC operation. The data from the warm experiments will be used to evaluate the best tubes to be used in the more time consuming cold experiments.

  11. Preliminary design of the beam screen cooling for the Future Circular Collider of hadron beams

    NASA Astrophysics Data System (ADS)

    Kotnig, C.; Tavian, L.

    2015-12-01

    Following recommendations of the recent update of the European strategy in particle physics, CERN has undertaken an international study of possible future circular colliders beyond the LHC. This study considers an option for a very high energy (100 TeV) hadron-hadron collider located in a quasi-circular underground tunnel having a circumference of 80 to 100 km. The synchrotron radiation emitted by the high-energy hadron beam increases by more than two orders of magnitude compared to the LHC. To reduce the entropic load on the superconducting magnets’ refrigeration system, beam screens are indispensable to extract the heat load at a higher temperature level. After illustrating the decisive constraints of the beam screen's refrigeration design, this paper presents a preliminary design of the length of a continuous cooling loop comparing helium and neon, for different cooling channel geometries with emphasis on the cooling length limitations and the exergetic efficiency.

  12. Thermomechanical assessment of the effects of a jaw-beam angle during beam impact on Large Hadron Collider collimators

    NASA Astrophysics Data System (ADS)

    Cauchi, Marija; Assmann, R. W.; Bertarelli, A.; Carra, F.; Lari, L.; Rossi, A.; Mollicone, P.; Sammut, N.

    2015-02-01

    The correct functioning of a collimation system is crucial to safely and successfully operate high-energy particle accelerators, such as the Large Hadron Collider (LHC). However, the requirements to handle high-intensity beams can be demanding, and accident scenarios must be well studied in order to assess if the collimator design is robust against possible error scenarios. One of the catastrophic, though not very probable, accident scenarios identified within the LHC is an asynchronous beam dump. In this case, one (or more) of the 15 precharged kicker circuits fires out of time with the abort gap, spraying beam pulses onto LHC machine elements before the machine protection system can fire the remaining kicker circuits and bring the beam to the dump. If a proton bunch directly hits a collimator during such an event, severe beam-induced damage such as magnet quenches and other equipment damage might result, with consequent downtime for the machine. This study investigates a number of newly defined jaw error cases, which include angular misalignment errors of the collimator jaw. A numerical finite element method approach is presented in order to precisely evaluate the thermomechanical response of tertiary collimators to beam impact. We identify the most critical and interesting cases, and show that a tilt of the jaw can actually mitigate the effect of an asynchronous dump on the collimators. Relevant collimator damage limits are taken into account, with the aim to identify optimal operational conditions for the LHC.

  13. Beam Coupling to Optical Scale Accelerating Structures

    SciTech Connect

    Sears, C.M.; Byer, R.L.; Colby, E.R.; Cowan, B.M.; Ischebeck, R.; Lincoln, M.R.; Siemann, R.H.; Spencer, J.E.; Plettner, T.; /Stanford U., Phys. Dept.

    2007-03-27

    Current research efforts into structure based laser acceleration of electrons utilize beams from standard RF linacs. These beams must be coupled into very small structures with transverse dimensions comparable to the laser wavelength. To obtain decent transmission, a permanent magnet quadrupole (PMQ) triplet with a focusing gradient of 560 T/m is used to focus into the structure. Also of interest is the induced wakefield from the structure, useful for diagnosing potential accelerator structures or as novel radiation sources.

  14. Microwave accelerator E-beam pumped laser

    DOEpatents

    Brau, Charles A. (Los Alamos, NM); Stein, William E. (Los Alamos, NM); Rockwood, Stephen D. (Los Alamos, NM)

    1980-01-01

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

  15. The status and prospects of the control system of an accelerator test facility for linear colliders

    NASA Astrophysics Data System (ADS)

    Urakawa, J.; Akiyama, H.; Akemoto, M.; Hayano, H.; Kawamoto, T.; Kurokawa, S.; Matsumoto, H.; Naito, T.; Takashima, T.; Takeda, S.; Yamamoto, N.; Yoshioka, M.; Yamaoka, Y.

    1990-08-01

    KEK has proposed to build an accelerator test facility (ATF) capable of producing a 2.5 GeV electron beam for the purpose of stimulating R&D for linear colliders in the TeV region. The ATF consists of a 1.54 GeV S-band linear accelerator, a 1.54 GeV damping ring and a 1.0 GeV X-band linear accelerator. The ATF project will be carried out in three phases. In phase I and phase II the S- and X-band linacs will be constructed, respectively, and in phase II the damping ring will be completed. The construction of ATF phase I has started, and the 0.3 GeV S-band injector linac is almost complete. The heart of the control system for the phase-I linac is based on two microVAX systems. At present these computers are connected to the KEK network (Ethernet). A CAMAC-enhanced byte-serial highway extends to the controlled equipment. Optical-fiber cables are used for the serial CAMAC highway in order to obtain high reliability in a noisy environment. The transmission rate on each optical fiber in 5 Mbyte/s. In this paper we present the status of the control system of the phase-I linac and the design of the computer control system for the ATF.

  16. Low-level RF signal processing for the Next Linear Collider Test Accelerator

    SciTech Connect

    Holmes, S.; Ziomek, C.; Adolphsen, C.

    1997-05-12

    In the X-band accelerator system for the Next Linear Collider Test Accelerator (NLCTA), the Low Level RF (LLRF) drive system must be very phase stable, but concurrently, be very phase agile. Phase agility is needed to make the Stanford Linear Doubler (SLED) power multiplier systems Energy work and to shape the RF waveforms to compensate beam loading in the accelerator sections. Similarly, precision fast phase and amplitude monitors are required to view, track, and feed back on RF signals at various locations throughout the system. The LLRF is composed of several subsystems: the RF Reference System generates and distributes a reference 11.424 GHz signal to all of the RF stations, the Signal Processing Chassis creates the RF waveforms with the appropriate phase modulation, and the Phase Detector Assembly measures the amplitude and phase of monitor3ed RF signals. The LLRF is run via VXI instrumentation. These instruments are controlled using HP VEE graphical programming software. Programs have been developed to shape the RF waveform, calibrate the phase modulators and demodulators, and display the measured waveforms. This paper describes these and other components of the LLRF system.

  17. Comparison of high-dose dosimetry systems for radiation damage studies in collider detectors and accelerators

    NASA Astrophysics Data System (ADS)

    Coninckx, F.; Schönbacher, H.; Tavlet, M.; Paic, G.; Razem, D.

    1993-10-01

    Measurements of absorbed dose in accelerator tunnels around primary beam areas are carried out on a routine basis at CERN. Dosimetric surveillance of high-energy particle accelerators has a great importance for the assessment of the radiation induced damage to materials and components used in high-level radiation areas. Standard dosimeters used at CERN for this purpose are polymer-alanine dosimeters (PAD) and radiophotoluminescent glass dosimeters (RPL). Ethanol-chlorobenzene dosimeters (ECB) for high-dose dosimetry, developed at the Ruder Boskovic Institute (RBI), have several interesting properties making their use in future multi-TeV colliders and detectors promising. These and RPL dosimeters were compared using the CERN alanine dosimetry as the reference system and 60Co gamma rays as the reference radiation. A very good agreement between the ECB and PAD was obtained for 60Co gamma irradiation whereas RPL overestimated the dose by about 15%. In mixed accelerator radiation fields the combination of the three dosimeters opens the possibility to estimate the total dose and the quality of the principal radiations contributing to the total radiation field.

  18. A nonlinear particle dynamics map of wakefield acceleration in a linear collider

    SciTech Connect

    Tajima, T.; Cheshkov, S.; Horton, W.; Yokoya, K.

    1998-08-01

    The performance of a wakefield accelerator in a high energy collider application is analyzed. In order to carry out this task, it is necessary to construct a strawman design system (no matter how preliminary) and build a code of the systems approach. A nonlinear dynamics map built on a simple theoretical model of the wakefield generated by the laser pulse (or whatever other method) is obtained and they employ this as a base for building a system with multi-stages (and components) as a high energy collider. The crucial figures of merit for such a system other than the final energy include the emittance (that determines the luminosity). The more complex the system is, the more opportunities the system has to degrade the emittance (or entropy of the beam). Thus the map gu ides one to identify where the crucial elements lie that affect the emittance. They find that a strong focusing force of the wakefield coupled with a possible jitter of the axis (or laser aiming) of each stage and a spread in the betatron frequencies arising from different phase space positions for individual particles leads to a phase space mixing. This sensitively controls the emittance degradation. They show that in the case of a uniform plasma the effect of emittance growth is large and may cause serious problems. They discuss possibilities to avoid it and control the situation.

  19. International Linear Collider Accelerator Physics R&D

    SciTech Connect

    George D. Gollin; Michael Davidsaver; Michael J. Haney; Michael Kasten; Jason Chang; Perry Chodash; Will Dluger; Alex Lang; Yehan Liu

    2008-09-03

    ILC work at Illinois has concentrated primarily on technical issues relating to the design of the accelerator. Because many of the problems to be resolved require a working knowledge of classical mechanics and electrodynamics, most of our research projects lend themselves well to the participation of undergraduate research assistants. The undergraduates in the group are scientists, not technicians, and find solutions to problems that, for example, have stumped PhD-level staff elsewhere. The ILC Reference Design Report calls for 6.7 km circumference damping rings (which prepare the beams for focusing) using conventional stripline kickers driven by fast HV pulsers. Our primary goal was to determine the suitability of the 16 MeV electron beam in the A region at Fermilab for precision kicker studies.We found that the low beam energy and lack of redundancy in the beam position monitor system complicated the analysis of our data. In spite of these issues we concluded that the precision we could obtain was adequate to measure the performance and stability of a production module of an ILC kicker, namely 0.5%. We concluded that the kicker was stable to an accuracy of ~2.0% and that we could measure this precision to an accuracy of ~0.5%. As a result, a low energy beam like that at A could be used as a rapid-turnaround facility for testing ILC production kicker modules. The ILC timing precision for arrival of bunches at the collision point is required to be 0.1 picosecond or better. We studied the bunch-to-bunch timing accuracy of a phase detector installed in A in order to determine its suitability as an ILC bunch timing device. A phase detector is an RF structure excited by the passage of a bunch. Its signal is fed through a 1240 MHz high-Q resonant circuit and then down-mixed with the A 1300 MHz accelerator RF. We used a kind of autocorrelation technique to compare the phase detector signal with a reference signal obtained from the phase detectors response to an event at the beginning of the run. We determined that the device installed in our beam, which was instrumented with an 8-bit 500 MHz ADC, could measure the beam timing to an accuracy of 0.4 picoseconds. Simulations of the device showed that an increase in ADC clock rate to 2 GHz would improve measurement precision by the required factor of four. As a result, we felt that a device of this sort, assuming matters concerning dynamic range and long-term stability can be addressed successfully, would work at the ILC. Cost effective operation of the ILC will demand highly reliable, fault tolerant and adaptive solutions for both hardware and software. The large numbers of subsystems and large multipliers associated with the modules in those subsystems will cause even a strong level of unit reliability to become an unacceptable level of system availability. An evaluation effort is underway to evaluate standards associated with high availability, and to guide ILC development with standard practices and well-supported commercial solutions. One area of evaluation involves the Advanced Telecom Computing Architecture (ATCA) hardware and software. We worked with an ATCA crate, processor monitors, and a small amount of ATCA circuit boards in order to develop a backplane spy board that would let us watch the ATCA backplane communications and pursue development of an inexpensive processor monitor that could be used as a physics-driven component of the crate-level controls system. We made good progress, and felt that we had determined a productive direction to extend this work. We felt that we had learned enough to begin designing a workable processor monitor chip if there were to be sufficient interest in ATCA shown by the ILC community. Fault recognition is a challenging issue in the crafting a high reliability controls system. With tens of thousands of independent processors running hundreds of thousands of critical processes, how can the system identify that a problem has arisen and determine the appropriate steps to take to correct, or compensate, for the failure? One possible solution might come through the use of the OpenClovis supervisory system, which runs on Linux processors and allows a select set of processors to monitor the behavior of individual processes and processors in a large, distributed controls network. We found that OpenClovis exhibited an irritating amount of sensitivity to the exact version of the Linux kernel running on the processors, and that it was poorly equipped to help us sort through problems that arose through conflicts so deep in the operating systems of the processors. But once this issue was addressed, we found that it performed as expected, recognizing crashes and process (and processor) failures.

  20. E-Beam Accelerator For Eximer Laser

    NASA Astrophysics Data System (ADS)

    Kovalchuk, Boris M.; Abdullin, Edward N.; Grishin, Dimitry M.; Gubanov, Vladimir P.; Zorin, Valery B.; Kim, Alexandre A.; Kumpjak, Eugeny V.; Morozov, Alexandre V.; Skakun, Victor S.; Steptchenko, Alexey S.; Tarasenko, Viktor F.; Tolkachev, Valery S.; Schanin, Peter M.; Tsou, Nikolay V.

    2002-12-01

    A high current e-beam accelerator for pumping of the 200 liter eximer laser is developed providing electron energy of 550 keV, diode current of 320 kA, e-beam current of 250 kA. The high voltage part of the accelerator consists of two linear transformers with the stored energy of 98 kJ. In order to reduce the influence of the self magnetic field on e-beam formation the vacuum diode is divided into 6 separate magnetically isolated diodes.

  1. Operational plasma density and laser parameters for future colliders based on laser-plasma accelerators

    SciTech Connect

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

    2012-12-21

    The operational plasma density and laser parameters for future colliders based on laser-plasma accelerators are discussed. Beamstrahlung limits the charge per bunch at low plasma densities. Reduced laser intensity is examined to improve accelerator efficiency in the beamstrahlung-limited regime.

  2. SINGLE CRYSTAL NIOBIUM TUBES FOR PARTICLE COLLIDERS ACCELERATOR CAVITIES

    SciTech Connect

    MURPHY, JAMES E

    2013-02-28

    The objective of this research project is to produce single crystal niobium (Nb) tubes for use as particle accelerator cavities for the Fermi laboratorys International Linear Collider project. Single crystal Nb tubes may have superior performance compared to a polycrystalline tubes because the absence of grain boundaries may permit the use of higher accelerating voltages. In addition, Nb tubes that are subjected to the high temperature, high vacuum crystallization process are very pure and well annealed. Any impurity with a significantly higher vapor pressure than Nb should be decreased by the relatively long exposure at high temperature to the high vacuum environment. After application of the single crystal process, the surfaces of the Nb tubes are bright and shiny, and the tube resembles an electro polished Nb tube. For these reasons, there is interest in single crystal Nb tubes and in a process that will produce single crystal tubes. To convert a polycrystalline niobium tube into a single crystal, the tube is heated to within a few hundred ?C of the melting temperature of niobium, which is 2477 ?C. RF heating is used to rapidly heat the tube in a narrow zone and after reaching the operating temperature, the hot zone is slowly passed along the length of the tube. For crystallization tests with Nb tubes, the traverse rate was in the range of 1-10 cm per hour. All the crystallization tests in this study were performed in a water-cooled, stainless steel chamber under a vacuum of 5 x10-6 torr or better. In earliest tests of the single crystal growth process, the Nb tubes had an OD of 1.9 cm and a wall thickness of 0.15 mm. With these relatively small Nb tubes, the single crystal process was always successful in producing single crystal tubes. In these early tests, the operating temperature was normally maintained at 2200 ?C, and the traverse rate was 5 cm per hour. In the next test series, the Nb tube size was increased to 3.8 cm OD and the wall thickness was increased 0.18 mm and eventually to 0.21 mm. Again, with these larger tubes, single crystal tubes were usually produced by the crystallization process. The power supply was generally operated at full output during these tests, and the traverse rate was 5 cm per hour. In a few tests, the traverse rate was increased to 10 cm per hour, and at the faster traverse rate, single crystal growth was not achieved. In these tests with a faster traverse rate, it was thought that the tube was not heated to a high enough temperature to achieve single crystal growth. In the next series of tests, the tube OD was unchanged at 3.8 cm and the wall thickness was increased to 0.30 mm. The increased wall thickness made it difficult to reach an operating temperature above 2,000 ?C, and although the single crystal process caused a large increase in the crystal grains, no single crystal tubes were produced. It was assumed that the operating temperature in these tests was not high enough to achieve single crystal growth. In FY 2012, a larger power supply was purchased and installed. With the new power supply, temperatures above the melting point of Nb were easily obtained regardless of the tube thickness. A series of crystallization tests was initiated to determine if indeed the operating temperature of the previous tests was too low to achieve single crystal growth. For these tests, the Nb tube OD remained at 3.8 cm and the wall thickness was 0.30 mm. The first test had an operating temperature of 2,000 ?C. and the operating temperature was increased by 50 ?C increments for each successive test. The final test was very near the Nb melting temperature, and indeed, the Nb tube eventually melted in the center of the tube. These tests showed that higher temperatures did yield larger grain sizes if the traverse rate was held constant at 5 cm per hour, but no single crystal tubes were produced even at the highest operating temperature. In addition, slowing the traverse rate to as low as 1 cm per hour did not yield a single crystal tube regardless of operating temperature. At this time, it appears that the wall thickness of the Nb tube rather than the operating temperature is the most important parameter to achieving single crystal growth. Single crystal growth was easily obtained with thinner wall tubes, but with thicker tubes, it was not achieved under varied growth conditions.

  3. ACCELERATOR PHYSICS ISSUES FOR FUTURE ELECTRON ION COLLIDERS.

    SciTech Connect

    PEGGS,S.; BEN-ZVI,I.; KEWISCH,J.; MURPHY,J.

    2001-06-18

    Interest continues to grow in the physics of collisions between electrons and heavy ions, and between polarized electrons and polarized protons [1,2,3]. Table 1 compares the parameters of some machines under discussion. DESY has begun to explore the possibility of upgrading the existing HERA-p ring to store heavy ions, in order to collide them with electrons (or positrons) in the HERA-e ring, or from TESLA [4]. An upgrade to store polarized protons in the HERA-p ring is also under discussion [1]. BNL is considering adding polarized electrons to the RHIC repertoire, which already includes heavy and light ions, and polarized protons. The authors of this paper have made a first pass analysis of this ''eRHIC'' possibility [5]. MIT-BATES is also considering electron ion collider designs [6].

  4. A normal conducting accelerator for a muon collider demonstration machine

    SciTech Connect

    Zhao, Y.; Palmer, R.; Fernow, R.; Gallardo, J.; Kirk, H.

    1997-05-01

    The authors present a 250 GeV linac arrangement using normal conducting cavities that could be used for a muon collider demonstration machine. One scenario consists of six 200 MHz linacs and rapid cycling pulsed magnets to be installed in a tunnel with six straight sections. The RF parameters of the cavities are given. Another scenario consists of 800 MHz. Also addressed is the possibility of using normal conducting cavities with liquid nitrogen cooling, which has several advantages.

  5. Pulsed power accelerators for particle beam fusion

    SciTech Connect

    Martin, T.H.; Barr, G.W.; VanDevender, J.P.; White, R.A.; Johnson, D.L.

    1980-01-01

    Sandia National Laboratories is completing the construction phase of the Particle Beam Fusion Accelerator-I (PBFA-I). Testing of the 36 module, 30 TW, 1 MJ output accelerator is in the initial stages. The 4 MJ, PBFA Marx generator has provided 3.6 MA into water-copper sulfate load resistors with a spread from first to last Marx firing between 15 to 25 ns and an output power of 5.7 TW. This accelerator is a modular, lower voltage, pulsed power device that is capable of scaling to power levels exceeding 100 TW. The elements of the PBFA technology and their integration into an accelerator system for particle beam fusion will be discussed.

  6. Explore the possibility of accelerating polarized He-3 beam in RHIC

    SciTech Connect

    Bai M.; Courant, E.; Fischer, W.; Ptitsyn, V.; Roser, T.

    2012-05-20

    As the world's first high energy polarized proton collider, RHIC has made significant progresses in measuring the proton spin structure in the past decade. In order to have better understanding of the contribution of up quarks and down quarks to the proton spin structure, collisions of high energy polarized neutron beams are required. Polarized He-3 beams offer an effectiveway to provide polarized neutron beams. In this paper, we present studies of accelerating polarized He-3 in RHIC with the current dual snake configuration. Possibilities of adding two more pairs of snakes for accelerating polarized He-3 were explored. Results of six snake configuration in RHIC are also reported in the paper.

  7. Linear beam-beam tune shift calculations for the Tevatron Collider

    SciTech Connect

    Johnson, D.

    1989-01-12

    A realistic estimate of the linear beam-beam tune shift is necessary for the selection of an optimum working point in the tune diagram. Estimates of the beam-beam tune shift using the ''Round Beam Approximation'' (RBA) have over estimated the tune shift for the Tevatron. For a hadron machine with unequal lattice functions and beam sizes, an explicit calculation using the beam size at the crossings is required. Calculations for various Tevatron lattices used in Collider operation are presented. Comparisons between the RBA and the explicit calculation, for elliptical beams, are presented. This paper discusses the calculation of the linear tune shift using the program SYNCH. Selection of a working point is discussed. The magnitude of the tune shift is influenced by the choice of crossing points in the lattice as determined by the pbar ''cogging effects''. Also discussed is current cogging procedures and presents results of calculations for tune shifts at various crossing points in the lattice. Finally, a comparison of early pbar tune measurements with the present linear tune shift calculations is presented. 17 refs., 13 figs., 3 tabs.

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

    SciTech Connect

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

    2011-03-01

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

  9. Observations of accelerated high current low emittance beams in the SLC Linac

    SciTech Connect

    Seeman, J.T.; Ross, M.C.; Sheppard, J.C.; Stiening, R.F.

    1985-05-01

    The Linac of the SLAC Linear Collider (SLC) is required to accelerate several intense single electron and positron bunches to high energy while not enlarging their small transverse emittances. The improvements needed by the SLAC Linac to meet these goals have very stringent design criteria. As partial systems have become available, beam tests have been performed to confirm the designs. The results of those beam tests are discussed. Future plans of the improvement program are described. 13 refs., 9 figs.

  10. SLAC electron-positron colliders: present and future

    SciTech Connect

    Richter, B.

    1986-09-01

    Stanford University's colliding beam program is outlined, including the SPEAR and PEP colliders and the SLAC linear collider. The accelerator developments to be pursued on these facilities are discussed, as well as advanced accelerator research and development. The items covered in the advanced accelerator research include beamstrahlung, stability requirements, breakdown limits, and power sources. (LEW)

  11. Summary Report of Working Group 4: e-Beam Driven Accelerators

    SciTech Connect

    Yakimenko, V.; Ischebeck, R.

    2006-11-27

    The working group considered high transformer ration schemes for an afterburner based on the design of a future linear collider. The main linac produces high charge beams of 100 GeV. A multiple stage plasma based accelerator would accelerate a portion of this beam to 500 GeV. The length of each plasma stage is expected to be of the order of a few meters while the isochronous beam transport required for multiple stages would occupy about a kilometer. Discussions in the working group were centered on issues to be addressed: ion motion in the plasma channel, positron side of accelerator ... The state of present e-beam driven plasma and dielectric Wakefield accelerators is very mature and closely resembles parameters of the afterburner for ILC. The main result of this working group is a multistage afterburner scheme of an afterburner for ILC and discussion of the experimental program to address main issues.

  12. Summary Report of Working Group 4: e-Beam Driven Accelerators

    NASA Astrophysics Data System (ADS)

    Yakimenko, V.; Ischebeck, R.

    2006-11-01

    The working group considered high transformer ration schemes for an afterburner based on the design of a future linear collider. The main linac produces high charge beams of 100 GeV. A multiple stage plasma based accelerator would accelerate a portion of this beam to 500 GeV. The length of each plasma stage is expected to be of the order of a few meters while the isochronous beam transport required for multiple stages would occupy about a kilometer. Discussions in the working group were centered on issues to be addressed: ion motion in the plasma channel, positron side of accelerator The state of present e-beam driven plasma and dielectric Wakefield accelerators is very mature and closely resembles parameters of the afterburner for ILC. The main result of this working group is a multistage afterburner scheme of an afterburner for ILC and discussion of the experimental program to address main issues.

  13. Theories of statistical equilibrium in electron-positron colliding-beam storage rings

    SciTech Connect

    Schonfeld, J.F.

    1985-01-01

    In this lecture I introduce you to some recent theoretical work that represents a significant and long overdue departure from the mainstream of ideas on the physics of colliding- beam storage rings. The goal of the work in question is to understand analytically - without recourse to computer simulation - the role that dissipation and noise play in the observed colliding-beam behavior of electron-positron storage rings.

  14. Issues and experience with controlling beam loss at the Tevatron collider

    SciTech Connect

    Annala, Gerald; /Fermilab

    2007-07-01

    Controlling beam loss in the Tevatron collider is of great importance because of the delicate nature of the cryogenic magnet system and the collider detectors. Maximizing the physics potential requires optimized performance as well as protection of all equipment. The operating history of the Tevatron has significantly influenced the way losses are managed. The development of beam loss management in the Tevatron will be presented.

  15. High-efficiency acceleration of an electron beam in a plasma wakefield accelerator.

    PubMed

    Litos, M; Adli, E; An, W; Clarke, C I; Clayton, C E; Corde, S; Delahaye, J P; England, R J; Fisher, A S; Frederico, J; Gessner, S; Green, S Z; Hogan, M J; Joshi, C; Lu, W; Marsh, K A; Mori, W B; Muggli, P; Vafaei-Najafabadi, N; Walz, D; White, G; Wu, Z; Yakimenko, V; Yocky, G

    2014-11-01

    High-efficiency acceleration of charged particle beams at high gradients of energy gain per unit length is necessary to achieve an affordable and compact high-energy collider. The plasma wakefield accelerator is one concept being developed for this purpose. In plasma wakefield acceleration, a charge-density wake with high accelerating fields is driven by the passage of an ultra-relativistic bunch of charged particles (the drive bunch) through a plasma. If a second bunch of relativistic electrons (the trailing bunch) with sufficient charge follows in the wake of the drive bunch at an appropriate distance, it can be efficiently accelerated to high energy. Previous experiments using just a single 42-gigaelectronvolt drive bunch have accelerated electrons with a continuous energy spectrum and a maximum energy of up to 85gigaelectronvolts from the tail of the same bunch in less than a metre of plasma. However, the total charge of these accelerated electrons was insufficient to extract a substantial amount of energy from the wake. Here we report high-efficiency acceleration of a discrete trailing bunch of electrons that contains sufficient charge to extract a substantial amount of energy from the high-gradient, nonlinear plasma wakefield accelerator. Specifically, we show the acceleration of about 74picocoulombs of charge contained in the core of the trailing bunch in an accelerating gradient of about 4.4gigavolts per metre. These core particles gain about 1.6gigaelectronvolts of energy per particle, with a final energy spread as low as 0.7 per cent (2.0 per cent on average), and an energy-transfer efficiency from the wake to the bunch that can exceed 30 per cent (17.7 per cent on average). This acceleration of a distinct bunch of electrons containing a substantial charge and having a small energy spread with both a high accelerating gradient and a high energy-transfer efficiency represents a milestone in the development of plasma wakefield acceleration into a compact and affordable accelerator technology. PMID:25373678

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

    SciTech Connect

    Zisman, Michael S.

    2007-09-25

    Historically, progress in particle physics has largely beendetermined by development of more capable particle accelerators. Thistrend continues today with the recent advent of high-luminosityelectron-positron colliders at KEK and SLAC operating as "B factories,"the imminent commissioning of the Large Hadron Collider at CERN, and theworldwide development effort toward the International Linear Collider.Looking to the future, one of the most promising approaches is thedevelopment of muon-beam accelerators. Such machines have very highscientific potential, and would substantially advance thestate-of-the-art in accelerator design. A 20-50 GeV muon storage ringcould serve as a copious source of well-characterized electron neutrinosor antineutrinos (a Neutrino Factory), providing beams aimed at detectorslocated 3000-7500 km from the ring. Such long baseline experiments areexpected to be able to observe and characterize the phenomenon ofcharge-conjugation-parity (CP) violation in the lepton sector, and thusprovide an answer to one of the most fundamental questions in science,namely, why the matter-dominated universe in which we reside exists atall. By accelerating muons to even higher energies of several TeV, we canenvision a Muon Collider. In contrast with composite particles likeprotons, muons are point particles. This means that the full collisionenergy is available to create new particles. A Muon Collider has roughlyten times the energy reach of a proton collider at the same collisionenergy, and has a much smaller footprint. Indeed, an energy frontier MuonCollider could fit on the site of an existing laboratory, such asFermilab or BNL. The challenges of muon-beam accelerators are related tothe facts that i) muons are produced as a tertiary beam, with very large6D phase space, and ii) muons are unstable, with a lifetime at rest ofonly 2 microseconds. How these challenges are accommodated in theaccelerator design will be described. Both a Neutrino Factory and a MuonCollider require large numbers of challenging superconducting magnets,including large aperture solenoids, closely spaced solenoids withopposing fields, shielded solenoids, very high field (~;40-50 T)solenoids, and storage ring magnets with a room-temperature midplanesection. Uses for the various magnets will be outlined, along withR&D plans to develop these and other required components of suchmachines.

  17. Particle accelerations in two colliding plasma shock waves

    NASA Astrophysics Data System (ADS)

    Takeuchi, Satoshi

    2016-01-01

    A kinetic model of the head-on collision of two magnetized plasma shocks is analyzed theoretically and with numerical calculations. Three-dimensional electromagnetic fields can be modeled as two magnetic fields that intersect at an arbitrary angle; such interaction plays an important role as the asymmetric collision of two shocks. The rate of increase of the attainable energy gain and the aspect ratio of an accelerating test particle are derived from theoretical analysis of the relativistic equations of motion. If the magnetic field has any curvature, a transverse magnetic field is generated that crosses the magnetic reconnection layer. The trajectory of the accelerating particle is bent by this magnetic field, producing the reduction of energy gain as a result.

  18. Production of an Accelerated Oxygen-14 Beam

    SciTech Connect

    Powell, James; O'Neil, James P.; Cerny, Joseph

    2002-05-03

    BEARS is an ongoing project to provide a light-ion radioactive-beam capability at the 88-Inch Cyclotron at LBNL. Light radioactive isotopes are produced at a 10 MeV proton medical cyclotron, transported 350 m via a high-speed gas transport capillary, cryogenically separated, and injected into the 88-Inch Cyclotron's ion source. The first radioactive beam successfully accelerated was Carbon-11 and beams of intensity more than 108 ions/sec have been utilized for experiments. Development of Oxygen-14 as the second BEARS beam presented considerable technical challenges, both due to its short half-life of 71 seconds and the radiation chemistry of oxygen in the target. The usual techniques developed for medical uses of Oxygen-15 involve the addition of significant amounts of carrier oxygen, something that would overload the ion source. As a solution, Oxygen-14 is produced as water in a carrier-free form, and is chemically converted in two steps to carbon dioxide, a form readily usable by the BEARS. This system has been built and is operational, and initial tests of accelerating an Oxygen-14 beam have been performed.

  19. POLARIZED ION SOURCES FOR HIGH ENERGY ACCELERATORS AND COLLIDERS

    SciTech Connect

    ZELENSKI,A.N.

    2000-10-16

    The recent progress in polarized ion source development is reviewed. In dc operation a 1.0 mA polarized H{sup -} ion current is now available from the Optically-Pumped Polarized Ion Source (OPPIS). In pulsed operation a 10 mA polarized H{sup -} ion current was demonstrated at the TRIUMF pulsed OPPIS test bench and a 3.5 mA peak current was obtained from an Atomic Beam Source (ABS) at the INR Moscow test bench. The possibilities for future improvements with both techniques are discussed. A new OPPIS for RHIC spin physics is described. The OPPIS reliably delivered polarized beam for the polarized run at RHIC. The results obtained with a new pulsed ABS injector for the IUCF Cooler Ring are also discussed.

  20. POLARIZED ION SOURCES FOR HIGH ENERGY ACCELERATORS AND COLLIDERS

    SciTech Connect

    ZELENSKI,A.N.

    2000-10-16

    The recent progress in polarized ion source development is reviewed. In dc operation a 1.0 mA polarized H{sup -} ion current is now available from the Optically-Pumped Polarized Ion Source (OPPIS) . In pulsed operation a 10 mA polarized H{sup -} ion current was demonstrated at the TRIUMF pulsed OPPIS test bench and a 3.5 mA peak current was obtained from an Atomic Beam Source (ABS) at the INR Moscow test bench. The possibilities for future improvements with both techniques are discussed. A new OPPIS for RHIC spin physics is described. The OPPIS reliably delivered polarized beam for the polarized run at RHIC. The results obtained with a new pulsed ABS injector for the IUCF Cooler Ring are also discussed.

  1. High-powered pulsed-ion-beam acceleration and transport

    SciTech Connect

    Humphries, S. Jr.; Lockner, T.R.

    1981-11-01

    The state of research on intense ion beam acceleration and transport is reviewed. The limitations imposed on ion beam transport by space charge effects and methods available for neutralization are summarized. The general problem of ion beam neutralization in regions free of applied electric fields is treated. The physics of acceleration gaps is described. Finally, experiments on multi-stage ion acceleration are summarized.

  2. The beam business: Accelerators in industry

    SciTech Connect

    Hamm, Robert W.; Hamm, Marianne E.

    2011-06-15

    Most physicists know that particle accelerators are widely used for treating cancer. But few are acquainted with the depth and breadth of their use in a myriad of applications outside of pure science and medicine. Society benefits from the use of particle beams in the areas of communications, transportation, the environment, security, health, and safety - in terms both of the global economy and quality of life. On the manufacturing level, the use of industrial accelerators has resulted in the faster and cheaper production of better parts for medical devices, automobiles, aircraft, and virtually all modern electronics. Consumers also benefit from the use of accelerators to explore for oil, gas, and minerals; sterilize food, wastewater, and medical supplies; and aid in the development of drugs and biomaterials.

  3. Colliding ionization injection in a plasma wakefield accelerator

    NASA Astrophysics Data System (ADS)

    Wan, Y.; Zhang, C. J.; Li, F.; Wu, Y. P.; Hua, J. F.; Pai, C.-H.; Lu, W.; Gu, Y. Q.; Xu, X. L.; Joshi, C.; Mori, W. B.

    2016-03-01

    A new scheme of generating high quality electron bunches via ionization injection triggered by an counter propagating laser pulse inside a beam driven plasma wake is proposed and examined via two-dimensional particle-in-cell (PIC) simulations. This scheme has two major advantages: first, the injection distance is easily tunable by varying the launching time or the focal position of the laser pulse; second, the electrons in each injected slice are released at nearly the same time. Both factors can significantly reduce the phase space mixing during the ionization injection process (Xu et al 2014 Phys. Rev. Lett. 112 035003, Xu et al 2014 Phys. Rev. Spec. Top.: Accel. Beams 17 061301, Li et al 2013 Phys. Rev. Lett. 111 015003), leading to very small energy spreads (∼10 keV for slice,∼100 keV for the whole bunch) and very small normalized emittance (∼few nm). As an example, a 4.5 fs 0.4 pC electron bunch with normalized emittance of 3.3 nm, slice energy spread of 13 keV, absolute energy spread of 80 keV, and a brightness of 7.2× {{10}18} A m‑2rad‑2 is obtained under realistic conditions. This scheme may have potential applications for future compact coherent light sources.

  4. Accelerating polarized beams at the AGS

    SciTech Connect

    Roser, T.

    1995-12-01

    The acceleration of polarized beams in circular accelerators is complicated by the presence of numerous depolarizing resonances. During acceleration, a depolarizing resonance is crossed whenever the spin precession frequency equals the frequency with which spin-perturbing magnetic fields are encountered. There are two main types of depolarizing resonances corresponding to the possible sources of such fields: imperfection resonances, which are driven by magnet errors and misalignments, and intrinsic resonances, driven by the focusing fields. The resonance conditions are usually expressed in terms of the spin tune {nu}{sub s}, which is defined as the number of spin precessions per revolution. For an ideal planar accelerator, where orbiting particles experience only the vertical guide field, the spin tune is equal to G{gamma}, where G = 1.7928 is the anomalous magnetic moment of the proton and {gamma} is the relativistic Lorentz factor. The resonance condition for imperfection depolarizing resonances arise when {nu}{sub s} = G{gamma} = n, where n is an integer. Imperfection resonances are therefore separated by only 523 MeV energy steps. The condition for intrinsic resonances is {nu}{sub s} = G{gamma} = kP {+-} {nu}{sub y}, where k is an integer, {nu}{sub y} is the vertical betatron tune and P is the superperiodicity. For the AGS, P = 12 and {nu}{sub y} {approx} 8.8. For most of the time during the acceleration cycle, the precession direction, or stable spin direction, coincides with the main vertical magnetic field. Close to a resonance, the stable spin direction is perturbed away from the vertical direction by the resonance driving fields. When a polarized beam is accelerated through an isolated resonance, the final polarization can be calculated analytically.

  5. Particle trapping and beam transport issues in laser driven accelerators

    NASA Astrophysics Data System (ADS)

    Gwenael, Fubiani; Wim, Leemans; Eric, Esarey

    2000-10-01

    The LWFA and colliding pulses [1][2] sheme are capable of producing very compact electron bunches where the longitudinal size is much smaller than the transverse size. In this case, even if the electrons are relativistic, space charge force can affect the longitudinal and transverse bunch properties [3][4]. In the Self-modulated regime and the colliding pulse sheme, electrons are trapped from the background plasma and rapidly accelerated. We present theoretical studies of the generation and transport of electron bunches in LWFAs. The space charge effect induced in the bunch is modelled assuming the bunch is ellipsoid like. Beam transport in vacuum, comparison between gaussian and waterbag distribution, comparison between envelope model and PIC simulation will be discussed. This work is supported by the Director, Office of Science, Office of High Energy & Nuclear Physics, High Energy Physics Division, of the U.S Department of Energy, under Contract No. DE-AC03-76SF00098 [1]E.Esarey et al.,IEEE Trans. Plasma Sci. PS-24,252 (1996); W.P. Leemans et al, ibidem, 331. [2]D. Umstadter et al., Phys. Rev. Lett. 76, 2073 (1996); E.Esarey et al., Phys. Rev. Lett. 79, 2682 (1997); C.B Schroeder et al., Phys. Rev. E59, 6037 (1999) [3]DESY M87-161 (1987); DESY M88-013 (1988) [4] R.W. Garnett and T.P Wangler, IEEE Part. Acce. Conf. (1991)

  6. Nonparaxial accelerating Bessel-like beams

    NASA Astrophysics Data System (ADS)

    Chremmos, Ioannis D.; Efremidis, Nikolaos K.

    2013-12-01

    A class of nonparaxial accelerating optical waves is introduced. These are beams with a Bessel-like profile that are capable of shifting laterally along fairly arbitrary trajectories as the wave propagates in free space. The concept expands on our previous proposal of paraxial accelerating Bessel-like beams to include beams with subwavelength lobes and/or large trajectory angles. Such waves are produced when the phase at the input plane is engineered so that the interfering ray cones are made to focus along the prespecified path. When the angle of these cones is fixed, the beams possess a diffraction-free Bessel profile on planes that stay normal to their trajectory, which can be considered as a generalized definition of diffractionless propagation in the nonparaxial regime. The analytical procedure leading to these results is based on a ray-optics interpretation of Rayleigh-Sommerfeld diffraction and is presented in detail. The evolution of the proposed waves is demonstrated through a series of numerical examples and a variety of trajectories.

  7. Straw man 900-1000 GeV crystal extraction test beam for Fermilab collider operation

    SciTech Connect

    Carrigan, R.A. Jr.

    1996-10-01

    A design for a 900-1000 GeV, 100 khz parasitic test beam for use during collider operations has been developed. The beam makes use of two bent crystals, one for extraction and the other one for redirecting the beam in to the present Switchyard beam system. The beam requires only a few modifications in the A0 area and largely uses existing devices. It should be straight-forward to modify one or two beam lines in the fixed target experimental areas to work above 800 GeV. Possibilities for improvements to the design,to operate at higher fluxes are discussed.

  8. Beam dynamics aspects of crab cavities in the CERN Large Hadron Collider

    SciTech Connect

    Sun, Y.; Calaga, R.; Assmann, R.; Barranco, J.; Tomas, R.; Weiler, T.; Zimmermann, F.; Morita, A.

    2009-10-14

    Modern colliders bring into collision a large number of bunches to achieve a high luminosity. The long-range beam-beam effects arising from parasitic encounters at such colliders are mitigated by introducing a crossing angle. Under these conditions, crab cavities (CC) can be used to restore effective head-on collisions and thereby to increase the geometric luminosity. Such crab cavities have been proposed for both linear and circular colliders. The crab cavities are rf cavities operated in a transverse dipole mode, which imparts on the beam particles a transverse kick that varies with the longitudinal position along the bunch. The use of crab cavities in the Large Hadron Collider (LHC) may not only raise the luminosity, but it could also complicate the beam dynamics, e.g., crab cavities might not only cancel synchrobetatron resonances excited by the crossing angle but they could also excite new ones, they could reduce the dynamic aperture for off-momentum particles, they could influence the aperture and orbit, also degrade the collimation cleaning efficiency, and so on. In this paper, we explore the principal feasibility of LHC crab cavities from a beam dynamics point of view. The implications of the crab cavities for the LHC optics, analytical and numerical luminosity studies, dynamic aperture, aperture and beta beating, emittance growth, beam-beam tune shift, long-range collisions, and synchrobetatron resonances, crab dispersion, and collimation efficiency will be discussed.

  9. SLAC linear collider

    SciTech Connect

    Richter, B.; Bell, R.A.; Brown, K.L.

    1980-06-01

    The SLAC LINEAR COLLIDER is designed to achieve an energy of 100 GeV in the electron-positron center-of-mass system by accelerating intense bunches of particles in the SLAC linac and transporting the electron and positron bunches in a special magnet system to a point where they are focused to a radius of about 2 microns and made to collide head on. The rationale for this new type of colliding beam system is discussed, the project is described, some of the novel accelerator physics issues involved are discussed, and some of the critical technical components are described.

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

    SciTech Connect

    Lidia, Steven M.

    1999-11-01

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

  11. Method and apparatus for varying accelerator beam output energy

    DOEpatents

    Young, Lloyd M.

    1998-01-01

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

  12. Solid Target Studies for Muon Colliders And Neutrino Beams

    SciTech Connect

    Simos, N.; Kirk, H.; Ludewig, H.; Thieberger, P.; Weng, W.T.; Trung, P.T.; McDonald, K.; Sheppard, J.; Yoshimura, K.; Hayato, Y.; /KEK, Tsukuba

    2006-05-10

    This paper presents preliminary results from an ongoing post-irradiation analysis of materials that have been irradiated at the Brookhaven National Laboratory (BNL) Isotope facility. The effort is part of an experimental study that focuses on how prone to irradiation damage these materials are and thus what is their potential in playing the role of high power targets in the neutrino superbeam and the muon collider initiatives.

  13. Accelerator limitations to ion beam analysis

    NASA Astrophysics Data System (ADS)

    Klatt, Ch.; Hartmann, B.; Kalbitzer, S.

    1997-02-01

    Energy spread of ion beams is an important limitation of nuclear reaction analysis. While in single-stage electrostatic accelerators ion source or high voltage instabilities predominate, tandem type machines exhibit the stripping process as an additional and rather complex source of energy broadening. We have investigated the energy widths of the ions 1H and 15N for resonance reactions and 4He from a 3 MV tandem accelerator operated with a gas stripping column. Major differences between the final energy spread of injected atomic and molecular negative ions have been observed. Molecular break-up and energy-loss straggling may easily amount to a few keV, whereas the contribution by high voltage ripple is negligible in most cases. The results will be discussed in view of their impact on different analytical techniques for high-resolution analysis of thin solid films.

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

    SciTech Connect

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

    2011-08-19

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

  15. Beam Dynamics Studies for a Laser Acceleration Experiment

    SciTech Connect

    Colby, e.; Noble, R.; Palmer, D.; Siemann, R.; Spencer, J

    2005-05-17

    The NLC Test Accelerator (NLCTA) at SLAC was built to address various beam dynamics issues for the Next Linear Collider. An S-Band RF gun is being installed together with a large-angle extraction line at 60 MeV followed by a matching section, buncher and final focus for the laser acceleration experiment, E163. The laser-electron interaction area is followed by a broad range, high resolution spectrometer (HES) for electron bunch analysis. Another spectrometer at 6 MeV will be used for analysis of bunch charges up to 1 nC. Emittance compensating solenoids and the low energy spectrometer (LES) will be used to tune for best operating point and match to the linac. Optical symmetries in the design of the 25.5{sup o} extraction line provide 1:1 phase space transfer without use of sextupoles for a large, 6D phase space volume and range of input conditions. Design techniques, tolerances, tuning sensitivities and orthogonal knobs are discussed.

  16. e-Beam Driven Accelerators: Working Group Summary

    SciTech Connect

    Muggli, P.; Ng, J.S.T.

    2004-12-07

    The working group has identified the parameters of an afterburner based on the design of a future linear collider. The new design brings the center of mass energy of the collider from 1 to 2 TeV. The afterburner is located in the final focus section of the collider, operates at a gradient of {approx_equal}4 GeV/m, and is only about 125 m long. Very important issues remain to be addressed, and include the physics and design of the positron side of the afterburner, as well as of the final focus system. Present plasma wakefield accelerator experiments have reached a level of maturity and of relevance to the afterburner, that make it timely to involve the high energy physics and accelerator community in the afterburner design process. The main result of this working group is the first integration of the designs of a future linear collider and an afterburner.

  17. E-Beam Driven Accelerators: Working Group Summary

    SciTech Connect

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

    2005-07-12

    The working group has identified the parameters of an afterburner based on the design of a future linear collider. The new design brings the center of mass energy of the collider from 1 to 2 TeV. The afterburner is located in the final focus section of the collider, operates at a gradient of {approx}4 GeV/m, and is only about 125 m long. Very important issues remain to be addressed, and include the physics and design of the positron side of the afterburner, as well as of the final focus system. Present plasma wakefield accelerator experiments have reached a level of maturity and of relevance to the afterburner, that make it timely to involve the high energy physics and accelerator community in the afterburner design process. The main result of this working group is the first integration of the designs of a future linear collider and an afterburner.

  18. Observation of shape-preserving accelerating underwater acoustic beams

    NASA Astrophysics Data System (ADS)

    Bar-Ziv, Uri; Postan, Aharon; Segev, Mordechai

    2015-09-01

    We present the experimental generation and observation of an underwater acoustic accelerating beam. The beam was generated by phase modulating a single projector using a tailored acoustic phase mask. The beam is propagating for a range in excess of 800 wavelengths, which are about six Rayleigh lengths, while preserving its shape and transversely accelerating. Such beams have promising applications in the fields of sonar, hydrography, and medical ultrasound and can provide new means to study nonlinear interaction of acoustic beams.

  19. Linear collider development at SLAC

    SciTech Connect

    Irwin, J.

    1993-08-01

    Linear collider R&D at SLAC comprises work on the present Stanford Linear Collider (SLC) and work toward the next linear collider (NLC). Recent SLC developments are summarized. NLC studies are divided into hardware-based and theoretical. We report on the status of the NLC Test Accelerator (NLCTA) and the final focus test beam (FFTB), describe plans for ASSET, an installation to measure accelerator structure wakefields, and mention IR design developments. Finally we review recent NLC theoretical studies, ending with the author`s view of next linear collider parameter sets.

  20. Characterisation of electron beams from laser-driven particle accelerators

    SciTech Connect

    Brunetti, E.; Manahan, G. G.; Shanks, R. P.; Islam, M. R.; Ersfeld, B.; Anania, M. P.; Cipiccia, S.; Issac, R. C.; Vieux, G.; Welsh, G. H.; Wiggins, S. M.; Jaroszynski, D. A.

    2012-12-21

    The development, understanding and application of laser-driven particle accelerators require accurate measurements of the beam properties, in particular emittance, energy spread and bunch length. Here we report measurements and simulations showing that laser wakefield accelerators can produce beams of quality comparable to conventional linear accelerators.

  1. High-energy-accelerator and colliding-beam user group

    NASA Astrophysics Data System (ADS)

    Three major areas are covered, progress report, budget report, and proposed research program. The progress report covers the following major topics: electron-positron interactions at PETRA with PLUTO; neutrino-deuterium interactions in the 15 foot bubble chamber; hadron jet physics experiment at Fermilab; status of neutrino-electron and proton-proton scattering experiments at Los Alamos; and work on future projects.

  2. Expanded studies of linear collider final focus systems at the Final Focus Test Beam

    SciTech Connect

    Tenenbaum, P.G.

    1995-12-01

    In order to meet their luminosity goals, linear colliders operating in the center-of-mass energy range from 3,50 to 1,500 GeV will need to deliver beams which are as small as a few Manometers tall, with x:y aspect ratios as large as 100. The Final Focus Test Beam (FFTB) is a prototype for the final focus demanded by these colliders: its purpose is to provide demagnification equivalent to those in the future linear collider, which corresponds to a focused spot size in the FFTB of 1.7 microns (horizontal) by 60 manometers (vertical). In order to achieve the desired spot sizes, the FFTB beam optics must be tuned to eliminate aberrations and other errors, and to ensure that the optics conform to the desired final conditions and the measured initial conditions of the beam. Using a combination of incoming-beam diagnostics. beam-based local diagnostics, and global tuning algorithms, the FFTB beam size has been reduced to a stable final size of 1.7 microns by 70 manometers. In addition, the chromatic properties of the FFTB have been studied using two techniques and found to be acceptable. Descriptions of the hardware and techniques used in these studies are presented, along with results and suggestions for future research.

  3. Operational Head-on Beam-Beam Compensation with Electron Lenses in the Relativistic Heavy Ion Collider.

    PubMed

    Fischer, W; Gu, X; Altinbas, Z; Costanzo, M; Hock, J; Liu, C; Luo, Y; Marusic, A; Michnoff, R; Miller, T A; Pikin, A I; Schoefer, V; Thieberger, P; White, S M

    2015-12-31

    Head-on beam-beam compensation has been implemented in the Relativistic Heavy Ion Collider in order to increase the luminosity delivered to the experiments. We discuss the principle of combining a lattice for resonance driving term compensation and an electron lens for tune spread compensation. We describe the electron lens technology and its operational use. To date, the implemented compensation scheme approximately doubled the peak and average luminosities. PMID:26764995

  4. Operational head-on beam-beam compensation with electron lenses in the Relativistic Heavy Ion Collider

    SciTech Connect

    Fischer, W.; Gu, X.; Altinbas, Z.; Costanzo, M.; Hock, J.; Liu, C.; Luo, Y.; Marusic, A.; Michnoff, R.; Miller, T. A.; Pikin, A. I.; Schoefer, V.; Thieberfer, P.; White, S. M.

    2015-11-25

    Head-on beam-beam compensation has been implemented in the Relativistic Heavy Ion Collider (RHIC) in order to increase the luminosity delivered to the experiments. We discuss the principle of combining a lattice for resonance driving term compensation and an electron lens for tune spread compensation. We describe the electron lens technology and its operational use. As of this date the implemented compensation scheme approximately doubled the peak and average luminosities.

  5. Operational head-on beam-beam compensation with electron lenses in the Relativistic Heavy Ion Collider

    DOE PAGESBeta

    Fischer, W.; Gu, X.; Altinbas, Z.; Costanzo, M.; Hock, J.; Liu, C.; Luo, Y.; Marusic, A.; Michnoff, R.; Miller, T. A.; et al

    2015-12-23

    Head-on beam-beam compensation has been implemented in the Relativistic Heavy Ion Collider (RHIC) in order to increase the luminosity delivered to the experiments. We discuss the principle of combining a lattice for resonance driving term compensation and an electron lens for tune spread compensation. We describe the electron lens technology and its operational use. As of this date the implemented compensation scheme approximately doubled the peak and average luminosities.

  6. Operational Head-on Beam-Beam Compensation with Electron Lenses in the Relativistic Heavy Ion Collider

    NASA Astrophysics Data System (ADS)

    Fischer, W.; Gu, X.; Altinbas, Z.; Costanzo, M.; Hock, J.; Liu, C.; Luo, Y.; Marusic, A.; Michnoff, R.; Miller, T. A.; Pikin, A. I.; Schoefer, V.; Thieberger, P.; White, S. M.

    2015-12-01

    Head-on beam-beam compensation has been implemented in the Relativistic Heavy Ion Collider in order to increase the luminosity delivered to the experiments. We discuss the principle of combining a lattice for resonance driving term compensation and an electron lens for tune spread compensation. We describe the electron lens technology and its operational use. To date, the implemented compensation scheme approximately doubled the peak and average luminosities.

  7. Operation of the CDF Silicon Vertex Detector with colliding beams at Fermilab

    SciTech Connect

    Bedeschi, F.; Bolognesi, V.; Dell'Agnello, S.; Galeotti, S.; Grieco, G.; Mariotti, M.; Menzione, A.; Punzi, G.; Raffaelli, F.; Ristori, L.; Tartarelli, F.; Turini, N.; Wenzel, H.; Zetti, F. ); Bailey, M.W.; Garfinkel, A.F.; Kruse, M.C.; Shaw, N.M. ); Carithers, W.C.; Ely, R.; Haber, C.; Holland, S.; Kleinfelder, S.; Merrick, T.; Schneide

    1992-10-01

    In this paper we briefly describe the main features of the CDF Silicon Vertex Detector (SVX) and discuss its performance during actual colliding beam operation at the Fermilab Tevatron. Details on S/N ratio, alignment, resolution and efficiency are given.

  8. High-gradient two-beam accelerator structure

    NASA Astrophysics Data System (ADS)

    Kazakov, S. Yu; Kuzikov, S. V.; Jiang, Y.; Hirshfield, J. L.

    2010-07-01

    A novel cavity structure is described that could be the basis for a two-beam, high-gradient, accelerator. Versions of the structure could be used for acceleration of beams of electrons, positrons, muons, protons, or heavier ions; with either electron or proton drive beams. The structure embodies cavities that are excited in several harmonically related eigenmodes, such that rf fields reach their peak values only during small portions of each basic rf period. This feature could help raise breakdown and pulse heating thresholds. The two-beam accelerator structure comprises chains of these cavities. In this configuration, no transfer elements are needed to couple rf energy from the drive beam to the accelerated beam, since both beams traverse the same cavities. Purposeful cavity detuning is used to provide much smaller deceleration for a high-current drive beam, than acceleration for a low-current accelerated beam, i.e., to provide a high transformer ratio. A self-consistent theory is presented to calculate idealized acceleration gradient, transformer ratio, and efficiency for energy transfer from the drive beam to the accelerated beam, for either parallel or antiparallel motion of the beams. The theory has been cast in dimensionless quantities so as to facilitate optimization with respect to efficiency, acceleration gradient, or transformer ratio, and to illuminate the interdependence of these parameters. Means for dramatically shortening the structure fill time are also described. However, no beam dynamics analysis is presented, so the range of parameters within which this new acceleration concept can be used will remain uncertain until it is established that stable beam transport along the structure using an appropriate focusing system is possible.

  9. "Accelerators and beams," a multimedia tutorial

    NASA Astrophysics Data System (ADS)

    Silbar, Richard R.

    1997-02-01

    We are developing a computer-based tutorial for charged-particle beam optics under a grant from the DOE. This subject is important to the DOE not only for its use in providing basic research tools but because the physics is the underpinning for accelerators used in industry and medicine. The tutorial, which will be delivered on Macintosh and Windows platforms, uses multimedia techniques to enhance the student's rate of learning and length of retention of the material. As such, it integrates our interactive On-Screen Laboratories with hypertext, line drawings, photographs, animation, video, and sound. We are targeting an audience from technicians to graduate students in science and engineering. At this time we have about a fourth of the material (about equivalent to a one-semester three-credit-hour upper under-graduate physics course) available in prototype form.

  10. Spin Polarization of proton and B^11 Beams for the Colliding Beam Fusion Reactor

    NASA Astrophysics Data System (ADS)

    Monkhorst, Hendrik J.; Rostoker, Norman; Binderbauer, Michl

    1998-11-01

    The kinematics of the p+B^11 resonant fusion reaction, including angular momentum conservation, shows that it is possible to enhance its cross section by polarizing the spins of p and B^11 (N. Rostoker, M. Binderbauer and H.J.Monkhorst, Science 278), 1419(1997).. The maximum spin enhancement is 60 percents, to be compared with enhancements of 50 percents for d-t and d-He^3 fusion. There may be an additional enhancement for p-B^11 due to the prolate, nonspherical shape of the B^11 nucleus. However, this effect would be probably small. Schemes for nuclear polarization will be explained. These methods will use optical pumping, Stern-Gerlach and/or rf techniques. Results of some polarization kinetics will be reported. The FRC plasma at the heart of the Colliding Beam Fusion Reactor is ideally suited for the use of polarized fuel. It will be shown that depolarization rates are negligible on fusion and diffusion time scales (H. J. Monkhorst, M. W. Binderbauer and N. Rostoker, Conference Proceedings, in the press). This situation is unlike that for tokamaks, for which these rates are unacceptably large (B. Coppi et al),Phys. Fluids, 29, 4060 (1986)..

  11. High-energy accelerator for beams of heavy ions

    DOEpatents

    Martin, Ronald L.; Arnold, Richard C.

    1978-01-01

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

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

    SciTech Connect

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

    2011-11-28

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

  13. Electron beam pointing stability of a laser wakefield accelerator

    NASA Astrophysics Data System (ADS)

    Issac, R. C.; Vieux, G.; Welsh, G. H.; Shanks, R.; Brunetti, E.; Cipiccia, S.; Anania, M. P.; Yang, X.; Wiggins, S. M.; Islam, M. R.; Ersfeld, B.; Farmer, J.; Raj, G.; Chen, S.; Clark, D.; McCanny, T.; Jaroszynski, D. A.

    2009-05-01

    Electron acceleration using plasma waves driven by ultra-short relativistic intensity laser pulses has undoubtedly excellent potential for driving a compact light source. However, for a wakefield accelerator to become a useful and reliable compact accelerator the beam properties need to meet a minimum standard. To demonstrate the feasibility of a wakefield based radiation source we have reliably produced electron beams with energies of 82+/-5 MeV, with 1+/-0.2% energy spread and 3 mrad r.m.s. divergence using a 0.9 J, 35 fs 800 nm laser. Reproducible beam pointing is essential for transporting the beam along the electron beam line. We find experimentally that electrons are accelerated close to the laser axis at low plasma densities. However, at plasma densities in excess of 1019 cm-3, electron beams have an elliptical beam profile with the major axis of the ellipse rotated with respect to the direction of polarization of the laser.

  14. Calculation of integrated luminosity for beams stored in the Tevatron collider

    SciTech Connect

    Finley, D.A.

    1989-03-20

    A model for calculating the integrated luminosity of beams stored in the Tevatron collider will be presented. The model determines the instantaneous luminosity by calculating the overlap integral of bunched beams passing through the interaction region. The calculation accounts for the variation in beam size due to the beta functions and also for effects due to finite longitudinal emittance and non-zero dispersion in the interaction region. The integrated luminosity is calculated for the beams as they evolve due to processes including collisions and intrabeam scattering. The model has been applied to both the extant and upgraded Tevatron collider, but is not limited to them. The original motivation for developing the computer model was to determine the reduction in luminosity due to beams with non-zero longitudinal emittances. There are two effects: the transverse beam size is increased where the dispersion is non-zero; the finite length of the beam bunch combined with an increasing /beta/ function results in an increased transverse beam size at the ends of the bunch. The derivation of a sufficiently useful analytic expression for the luminosity proved to be intractable. Instead, a numerical integration computer program was developed to calculate the luminosity in the presence of a finite longitudinal emittance. The program was then expanded into a model which allows the luminosity to vary due to changes in emittances and reduction in bunch intensities. At that point, it was not difficult to calculate the integrated luminosity. 5 refs., 2 figs., 4 tabs.

  15. Interactive beam tuning simulator for the SLC (Stanford Linear Collider) final focus

    SciTech Connect

    Ford, W.T.; Kozanecki, W.; Lohse, T.; Servranckx, R.V.

    1989-03-01

    An interface to the DIMAD beam optics computer program enables the operator to perform in simulation the sequence of magnet adjustments that would be used online for tuning the Stanford Linear Collider Final Focus System. The program accepts any input beam matrix from a disk file and presents a menu of magnet adjustments and scan and display options. The results of a ray trace calculation are presented as profiles or envelope plots on the graphics screen. We give results from studies of the optimization of the beam under various input conditions. 11 refs., 4 figs.

  16. Target Material Irradiation Studies for High-Intensity Accelerator Beams

    SciTech Connect

    Simos, N.; Kirk, H.; Ludewig, H.; Thieberger, P.; Weng, W.T.; McDonald, K.; Sheppard, J.; Evangelakis, G.; Yoshimura, K.; /KEK, Tsukuba

    2005-08-16

    This paper presents results of recent experimental studies focusing on the behavior of special materials and composites under irradiation conditions and their potential use as accelerator targets. The paper also discusses the approach and goals of on-going investigations on an expanded material matrix geared toward the neutrino superbeam and muon collider initiatives.

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

    SciTech Connect

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

    2010-10-27

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

  18. Advanced accelerating structures and their interaction with electron beams.

    SciTech Connect

    Gai, W.; High Energy Physics

    2008-01-01

    In this paper, we give a brief description of several advanced accelerating structures, such as dielectric loaded waveguides, photonic band gap, metamaterials and improved iris-loaded cavities. We describe wakefields generated by passing high current electron beams through these structures, and applications of wakefields to advanced accelerator schemes. One of the keys to success for high gradient wakefield acceleration is to develop high current drive beam sources. As an example, the high current RF photo injector at the Argonne Wakefield Accelerator, passed a {approx}80 nC electron beam through a high gradient dielectric loaded structure to achieve a 100 MV/m gradient. We will summarize recent related experiments on beam-structure interactions and also discuss high current electron beam generation and propagation and their applications to wakefield acceleration.

  19. Advanced Accelerating Structures and Their Interaction with Electron Beams

    SciTech Connect

    Gai Wei

    2009-01-22

    In this paper, we give a brief description of several advanced accelerating structures, such as dielectric loaded waveguides, photonic band gap, metamaterials and improved iris-loaded cavities. We describe wakefields generated by passing high current electron beams through these structures, and applications of wakefields to advanced accelerator schemes. One of the keys to success for high gradient wakefield acceleration is to develop high current drive beam sources. As an example, the high current RF photo injector at the Argonne Wakefield Accelerator, passed a {approx}80 nC electron beam through a high gradient dielectric loaded structure to achieve a 100 MV/m gradient. We will summarize recent related experiments on beam-structure interactions and also discuss high current electron beam generation and propagation and their applications to wakefield acceleration.

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

    DOE PAGESBeta

    Shin, Young-Min

    2014-09-15

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

  1. Minimal interference beam size/profile measurement techniques applicable to the Collider

    SciTech Connect

    Nexsen, W.; Dutt, S.; Kauffmann, S.; Lebedev, V.; Maschke, A.; Mokhov, N.; Richardson, R.; Tsyganov, E.; Zinchenko, A.

    1993-05-01

    The imaging of synchrotron radiation (SR) has been suggested as a technique for providing a continuous, non-interfering monitor of the beam profile in the Collider rings at the Superconducting Super Collider. A closer examination has raised questions concerning the applicability of SR imaging in this case because of the diffraction broadening of the image, the requirements for axial space and location in the lattice, and the complexity of the system. We have surveyed the known, alternative, minimal interference techniques for measuring beam size and have evaluated them for possible Collider usage. We conclude that of the approaches that appear feasible, all require at least some development for our usage and that the development of an electron beam probe offers the best promise. We recommend that flying wires be used for cross-checking and calibrating the electron beam probe diagnostic and for luminosity measurements when the highest accuracy is required, but flying wires should not be used as the primary diagnostic because of their limited lifetime.

  2. Particle Beam Waist Location in Plasma Wakefield Acceleration

    NASA Astrophysics Data System (ADS)

    Down, Adrian; Mori, Warren; Zhou, Miaomiao

    2007-03-01

    The role of beam waist location in interactions between a plasma and a particle beam is not yet fully understood. Nonlinear effects within the plasma make an analysis of such interactions difficult. I present five simulations in which I vary the waist location of a beam of ultra-relativistic electrons propagating through one meter of self-ionized lithium plasma. The simulation parameters are chosen to model the recent experiment 167 at the Stanford Linear Accelerator, relevant to the design of future plasma wakefield accelerating afterburners. I find that beams focused near the point of entry into the plasma propagate further into the plasma and accelerates witness particles to a greater maximum energy before disintegrating. These results could indicate that ion channel formation is dependent on the drive beam waist location and that the plasma accelerating medium can have an observable effect on the focusing of the drive beam.

  3. Frontiers of accelerator instrumentation

    SciTech Connect

    Ross, M.

    1992-08-01

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

  4. Design of inductively detuned RF extraction cavities for the Relativistic Klystron Two Beam Accelerator

    SciTech Connect

    Henestroza, E.; Yu, S.S.; Li, H.

    1995-04-01

    An inductively detuned traveling wave cavity for the Relativistic Klystron Two Beam Accelerator expected to extract high RF power at 11. 424 GHz for the 1 TeV Center of Mass Next Linear Collider has been designed. Longitudinal beam dynamics studies led to the following requirements on cavity design: (a) Extraction of 360 MW of RF power with RF component of the current being 1.15 kAmps at 11.424 GHz, (b) Inductively detuned traveling wave cavity with wave phase velocity equal to 4/3 the speed of light, (c) Output cavity with appropriate Q{sub ext} and eigenfrequency for proper matching. Furthermore, transverse beam dynamics require low shunt impedances to avoid the beam break-up instability. We describe the design effort to meet these criteria based on frequency-domain and time-domain computations using 2D- and 3D- electromagnetic codes.

  5. Development of a Compact Rotating-Wave Electron Beam Accelerator

    SciTech Connect

    Velazco, Jose E.; Ceperley, Peter H.

    2003-08-26

    We present the successful prototype development results of a novel compact rotating-wave electron beam accelerator (RWA). The RWA uses a single cylindrical cavity holding a transverse-magnetic resonant mode in combination with an axial static magnetic field to accelerate electrons to higher energies. With approximately 80 kilowatts of microwave power fed into a C-band cavity, we have been able to successfully accelerate a 3 keV electron beam to {approx}760 keV. The compact RWA accelerator could be the basis for a new class of compact and affordable 1-10 MeV microwave accelerators for military, medical and industrial applications.

  6. Characteristics of an electron-beam rocket pellet accelerator

    SciTech Connect

    Tsai, C.C.; Foster, C.A.; Schechter, D.E.

    1989-01-01

    An electron-beam rocket pellet accelerator has been designed, built, assembled, and tested as a proof-of-principle (POP) apparatus. The main goal of accelerators based on this concept is to use intense electron-beam heating and ablation of a hydrogen propellant stick to accelerate deuterium and/or tritium pellets to ultrahigh speeds (10 to 20 km/s) for plasma fueling of next-generation fusion devices such as the International Thermonuclear Engineering Reactor (ITER). The POP apparatus is described and initial results of pellet acceleration experiments are presented. Conceptual ultrahigh-speed pellet accelerators are discussed. 14 refs., 8 figs.

  7. Characteristics of an electron-beam rocket pellet accelerator

    SciTech Connect

    Tsai, C.C.; Foster, C.A.; Milora, S.L.; Schechter, D.E.

    1991-01-01

    A proof-of-principle (POP) electron-beam pellet accelerator has been developed and used for accelerating hydrogen and deuterium pellets. An intact hydrogen pellet was accelerated to a speed of 460 m/s by an electron beam of 13.5 keV. 0.3 A, and 2 ms. The maximum speed is limited by the acceleration path length (0.4 m) and pellet integrity. Experimental data have been collected for several hundred hydrogen pellets, which were accelerated by electron beams with parameters of voltage up to 16 kV, current up to 0.4 A, and pulse length up to 10 ms. Preliminary results reveal that the measured burn velocity increases roughly with the square of the beam voltage, as the theoretical model predicts. The final pellet velocity is proportional to the exhaust velocity, which increases with the beam power. To reach the high exhaust velocity needed for accelerating pellets to >1000 m/s, a new electron gun, with its cathode indirectly heated by a graphite heater and an electron beam, is being developed to increase beam current and power. A rocket casing or shell around the pellet has been designed and developed to increase pellet strength and improve the electron-rocket coupling efficiency. We present the characteristics of this pellet accelerator, including new improvements. 13 refs., 6 figs.

  8. Superbunch hadron colliders.

    PubMed

    Takayama, Ken; Kishiro, Junichi; Sakuda, Makoto; Shimosaki, Yoshito; Wake, Masayoshi

    2002-04-01

    A novel concept of a high luminosity hadron collider is proposed. This would be a typical application of an induction synchrotron being newly developed. Extremely long bunches, referred to as superbunches, are generated by a multibunch stacking method employing barrier buckets at the injection into the collider and are accelerated with a step voltage induced in the induction gaps. Superbunches intersect with each other, yielding a luminosity of more than 10(35) cm(-2) sec(-1). A combination of vertical crossing and horizontal crossing must be employed in order to avoid any significant beam-beam tune shift. PMID:11955152

  9. Energy compensation of slow extracted beams with RF acceleration

    NASA Astrophysics Data System (ADS)

    Fujimoto, Tetsuya; Souda, Hikaru; Torikoshi, Masami; Kanai, Tatsuaki; Yamada, Satoru; Noda, Koji

    2016-03-01

    In a conventional carbon-ion radiotherapy facility, a carbon-ion beam is typically accelerated up to an optimum energy, slowly extracted from a synchrotron ring by a resonant slow extraction method, and ultimately delivered to a patient through a beam-delivery system. At Japan's Gunma University, a method employing slow-beam extraction along with beam-acceleration has been adopted. This method slightly alters the extracted-beam's energy owing to the acceleration component of the process, which subsequently results in a residual-range variation of approximately 2 mm in water-equivalent length. However, this range variation does not disturb a distal dose distribution with broad-beam methods such as the single beam-wobbling method. With the pencil-beam 3D scanning method, however, such a range variation disturbs a distal dose distribution because the variation is comparable to slice thickness. Therefore, for pencil-beam 3D scanning, an energy compensation method for a slow extracted beam is proposed in this paper. This method can compensate for the aforementioned energy variances by controlling net energy losses through a rotatable energy absorber set fixed between the synchrotron exit channel and the isocenter. Experimental results demonstrate that beam energies can be maintained constant, as originally hypothesized. Moreover, energy-absorber positions were found to be significantly enhanced by optimizing beam optics for reducing beam-size growth by implementation of the multiple-scattering effect option.

  10. Staging Laser Plasma Accelerators for Increased Beam Energy

    SciTech Connect

    Panasenko, D.; Shu, A. J.; Schroeder, C. B.; Gonsalves, A. J.; Nakamura, K.; Matlis, N. H.; Cormier-Michel, E.; Plateau, G.; Lin, C.; Toth, C.; Geddes, C. G. R.; Esarey, E.; Leemans, W. P.

    2009-01-22

    Staging laser plasma accelerators is an efficient way of mitigating laser pump depletion in laser driven accelerators and necessary for reaching high energies with compact laser systems. The concept of staging includes coupling of additional laser energy and transporting the electron beam from one accelerating module to another. Due to laser damage threshold constraints, in-coupling laser energy with conventional optics requires distances between the accelerating modules of the order of 10 m, resulting in decreased average accelerating gradient and complicated e-beam transport. In this paper we use basic scaling laws to show that the total length of future laser plasma accelerators will be determined by staging technology. We also propose using a liquid jet plasma mirror for in-coupling the laser beam and show that it has the potential to reduce distance between stages to the cm-scale.

  11. Staging laser plasma accelerators for increased beam energy

    SciTech Connect

    Panasenko, Dmitriy; Shu, Anthony; Schroeder, Carl; Gonsalves, Anthony; Nakamura, Kei; Matlis, Nicholas; Cormier-Michel, Estelle; Plateau, Guillaume; Lin, Chen; Toth, Csaba; Geddes, Cameron; Esarey, Eric; Leemans, Wim

    2008-09-29

    Staging laser plasma accelerators is an efficient way of mitigating laser pump depletion in laser driven accelerators and necessary for reaching high energies with compact laser systems. The concept of staging includes coupling of additional laser energy and transporting the electron beam from one accelerating module to another. Due to laser damage threshold constraints, in-coupling laser energy with conventional optics requires distances between the accelerating modules of the order of 10m, resulting in decreased average accelerating gradient and complicated e-beam transport. In this paper we use basic scaling laws to show that the total length of future laser plasma accelerators will be determined by staging technology. We also propose using a liquid jet plasma mirror for in-coupling the laser beam and show that it has the potential to reduce distance between stages to the cm-scale.

  12. Progress on Optimization of the Nonlinear Beam Dynamics in the MEIC Collider Rings

    SciTech Connect

    Morozov, Vasiliy S.; Derbenev, Yaroslav S.; Lin, Fanglei; Pilat, Fulvia; Zhang, Yuhong; Cai, Y.; Nosochkov, Y. M.; Sullivan, Michael; Wang, M.-H.; Wienands, Uli

    2015-09-01

    One of the key design features of the Medium-energy Electron-Ion Collider (MEIC) proposed by Jefferson Lab is a small beta function at the interaction point (IP) allowing one to achieve a high luminosity of up to 1034 cm-2s-1. The required strong beam focusing unavoidably causes large chromatic effects such as chromatic tune spread and beam smear at the IP, which need to be compensated. This paper reports recent progress in our development of a chromaticity correction scheme for the ion ring including optimization of dynamic aperture and momentum acceptance.

  13. Progress on optimization of the nonlinear beam dynamics in the MEIC collider rings

    SciTech Connect

    None, None

    2015-07-13

    One of the key design features of the Medium-energy Electron-Ion Collider (MEIC) proposed by Jefferson Lab is a small beta function at the interaction point (IP) allowing one to achieve a high luminosity of up to 1034 cm-2s-1. The required strong beam focusing unavoidably causes large chromatic effects such as chromatic tune spread and beam smear at the IP, which need to be compensated. This paper reports recent progress in our development of a chromaticity correction scheme for the ion ring including optimization of dynamic aperture and momentum acceptance.

  14. Development of the SSC (Superconducting Super Collider) trim coil beam tube assembly

    SciTech Connect

    Skaritka, J.; Kelly, E.; Schneider, W.; Shutt, R.; Thompson, P.; Wanderer, P.; Willen, E.; Bintinger, D.; Coluccio, R.; Schieber, L.

    1987-01-01

    The Superconducting Super Collider uses approx. =9600 dipole magnets. The magnets have been carefully designed to exhibit minimal magnetic field harmonics. However, because of superconductor magnetization effects, iron saturation and conductor/coil positioning errors, certain harmonic errors are possible and must be corrected by use of multipole correctors called trim coils. For the most efficient use of axial space in the magnet, and lowest possible current, a distributed internal correction coil design is planned. The trim coil assembly is secured to the beam tube, a uhv tube with special strength, size, conductivity and vacuum. The report details the SSC trim coil/beam tube assembly specifications, history, and ongoing development.

  15. Laser-and Beam-Driven Plasma Accelerators

    NASA Astrophysics Data System (ADS)

    Joshi, Chandrashekhar

    2006-10-01

    Scientists have been trying to use the tremendous electric fields in relativistic plasma waves to accelerate charged particles, and are now making substantial progress. If they succeed, future high energy accelerators will use plasma waves rather than microwave cavities as accelerating structures.Some accelerators, such as those used for radiation therapy will fit on a tabletop. Research on using plasma waves to accelerate particles began in earnest following the suggestion by John Dawson and his colleagues [1-3] that a relativistically propagating plasma wave or a wake field could be excited by using a powerful but short laser -or electron -beam as a driver pulse.Since their original suggestion the research on plasma --based accelerators has spread worldwide A series of experiments by the UCLA/USC/SLAC collaboration ,using the 30 GeV beam of the Stanford Linear Accelerator Center (SLAC), has demonstrated high-gradient acceleration of electrons and positrons using the the wake left by the SLAC beam as it passes through a lithium plasma. Electrons have been accelerated by more than 30 GeV in less than one meter. This acceleration gradient is about a thousand times larger than in conventional microwave-driven accelerators. It is a first step toward a ``plasma afterburner,'' which would be placed at the end of a kilometers-long conventional accelerator and double its beam energy in a few tens of meters. In addition to the acceleration of particle beams, these experiments have demonstrated the rich physics bounty to be reaped from relativistic beam-plasma interactions. This includes the generation of intense and narrowly collimated x-ray beams, refraction of particles at a plasma interface, and the creation of intense beams of positrons. These results are leading the way to similar tabletop accelerators based on plasma wakes excited by lasers rather than electron beams. Applications for tabletop accelerators include gamma radiography, radiation therapy, and ultra-fast materials science. [1] T.Tajima and J.M.Dawson Phys.Rev.Lett. 43,267.(1979) [2] P.Chen et.al. Phys.Rev.Lett.54,693,(1985) [3]C.Joshi et.al. Nature 311,525,(1984) In collaboration with all my past and present students and co-workers and in particular collaborators on E157,162,164 and 167 experiments at SLAC.

  16. Beam collimation and machine detector interface at the International Linear Collider

    SciTech Connect

    Mokhov, N.V.; Drozhdin, A.I.; Kostin, M.A.; /Fermilab

    2005-05-01

    Synchrotron radiation, beam-gas scattering and beam halo interactions with collimators and other components in the ILC beam delivery system (BDS) would create fluxes of muons and other secondaries which could exceed the tolerable levels at a detector by a few orders of magnitude. It is shown that with a multi-stage collimation system, magnetized iron spoilers which fill the tunnel and a set of masks in the detector, one can hopefully meet the design goals. Results of modeling with the STRUCT and MARS15 codes of beam loss and energy deposition effects are presented in this paper. We focus on the collimation system and mask performance optimization, short- and long-term survivability of the critical components (spoilers, absorbers and magnets), dynamic heat loads and radiation levels in magnets and other components, and machine-related backgrounds in collider detectors.

  17. High-gradient two-beam electron accelerator

    SciTech Connect

    Hirshfield, Jay L.

    2014-11-04

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

  18. Long bunch trains measured using a prototype cavity beam position monitor for the Compact Linear Collider

    NASA Astrophysics Data System (ADS)

    Cullinan, F. J.; Boogert, S. T.; Farabolini, W.; Lefevre, T.; Lunin, A.; Lyapin, A.; Søby, L.; Towler, J.; Wendt, M.

    2015-11-01

    The Compact Linear Collider (CLIC) requires beam position monitors (BPMs) with 50 nm spatial resolution for alignment of the beam line elements in the main linac and beam delivery system. Furthermore, the BPMs must be able to make multiple independent measurements within a single 156 ns long bunch train. A prototype cavity BPM for CLIC has been manufactured and tested on the probe beam line at the 3rd CLIC Test Facility (CTF3) at CERN. The transverse beam position is determined from the electromagnetic resonant modes excited by the beam in the two cavities of the pickup, the position cavity and the reference cavity. The mode that is measured in each cavity resonates at 15 GHz and has a loaded quality factor that is below 200. Analytical expressions for the amplitude, phase and total energy of signals from long trains of bunches have been derived and the main conclusions are discussed. The results of the beam tests are presented. The variable gain of the receiver electronics has been characterized using beam excited signals and the form of the signals for different beam pulse lengths with the 2 /3 ns bunch spacing has been observed. The sensitivity of the reference cavity signal to charge and the horizontal position signal to beam offset have been measured and are compared with theoretical predictions based on laboratory measurements of the BPM pickup and the form of the resonant cavity modes as determined by numerical simulation. Finally, the BPM was calibrated so that the beam position jitter at the BPM location could be measured. It is expected that the beam jitter scales linearly with the beam size and so the results are compared to predicted values for the latter.

  19. Design of a 1-MV induction injector for the Relativistic Klystron Two-Beam Accelerator

    SciTech Connect

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

    1997-05-01

    A Relativistic Klystron Two-Beam Accelerator (RK-TBA) is envisioned as a rf power source upgrade of the Next Linear Collider. Construction of a prototype, called the RTA, based on the RK-TBA concept has commenced at the Lawrence Berkeley National Laboratory. This prototype will be used to study physics, engineering, and costing issues involved in the application of the RK-TBA concept to linear colliders. The first half of the injector, a 1 MeV, 1.2 kA, 300 ns induction electron gun, has been built and is presently being tested. The design of the injector cells and the pulsed power drive units are presented in this paper.

  20. Prototyping of beam position monitor for medium energy beam transport section of RAON heavy ion accelerator.

    PubMed

    Jang, Hyojae; Jin, Hyunchang; Jang, Ji-Ho; Hong, In-Seok

    2016-02-01

    A heavy ion accelerator, RAON is going to be built by Rare Isotope Science Project in Korea. Its target is to accelerate various stable ions such as uranium, proton, and xenon from electron cyclotron resonance ion source and some rare isotopes from isotope separation on-line. The beam shaping, charge selection, and modulation should be applied to the ions from these ion sources because RAON adopts a superconducting linear accelerator structure for beam acceleration. For such treatment, low energy beam transport, radio frequency quadrupole, and medium energy beam transport (MEBT) will be installed in injector part of RAON accelerator. Recently, development of a prototype of stripline beam position monitor (BPM) to measure the position of ion beams in MEBT section is under way. In this presentation, design of stripline, electromagnetic (EM) simulation results, and RF measurement test results obtained from the prototyped BPM will be described. PMID:26932088

  1. Prototyping of beam position monitor for medium energy beam transport section of RAON heavy ion accelerator

    NASA Astrophysics Data System (ADS)

    Jang, Hyojae; Jin, Hyunchang; Jang, Ji-Ho; Hong, In-Seok

    2016-02-01

    A heavy ion accelerator, RAON is going to be built by Rare Isotope Science Project in Korea. Its target is to accelerate various stable ions such as uranium, proton, and xenon from electron cyclotron resonance ion source and some rare isotopes from isotope separation on-line. The beam shaping, charge selection, and modulation should be applied to the ions from these ion sources because RAON adopts a superconducting linear accelerator structure for beam acceleration. For such treatment, low energy beam transport, radio frequency quadrupole, and medium energy beam transport (MEBT) will be installed in injector part of RAON accelerator. Recently, development of a prototype of stripline beam position monitor (BPM) to measure the position of ion beams in MEBT section is under way. In this presentation, design of stripline, electromagnetic (EM) simulation results, and RF measurement test results obtained from the prototyped BPM will be described.

  2. Accelerators (3/5)

    ScienceCinema

    None

    2011-10-06

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

  3. Accelerators (4/5)

    ScienceCinema

    None

    2011-10-06

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

  4. Accelerators (3/5)

    SciTech Connect

    2009-07-07

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

  5. Accelerators (4/5)

    SciTech Connect

    2009-07-08

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

  6. Accelerators (5/5)

    SciTech Connect

    2009-07-09

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

  7. Accelerators (5/5)

    ScienceCinema

    None

    2011-10-06

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

  8. SLAC linear collider conceptual design report

    SciTech Connect

    Not Available

    1980-06-01

    The linear collider system is described in detail, including the transport system, the collider lattice, final focusing system, positron production, beam damping and compression, high current electron source, instrumentation and control, and the beam luminosity. The experimental facilities and the experimental uses are discussed along with the construction schedule and estimated costs. Appendices include a discussion of space charge effects in the linear accelerator, emittance growth in the collider, the final focus system, beam-beam instabilities and pinch effects, and detector backgrounds. (GHT)

  9. Ion beam divergence characteristics of two-grid accelerator systems

    NASA Technical Reports Server (NTRS)

    Aston, G.; Kaufman, H. R.; Wilbur, P. J.

    1978-01-01

    The first comprehensive experimental investigation of two-grid accelerator systems is presented. A wide range of geometrical grid parameters and grid set operating conditions were investigated for their effect on ion beam divergence. Ion beam divergence was found to depend most strongly on normalized perveance per hole, grid separation ratio, net-to-total accelerating voltage ratio, and discharge-to-total accelerating voltage ratio variations. The graphical results contained herein provide guidelines for the design of ion accelerator systems. A general ion beam divergence angle correlation was developed to permit approximate beam divergence estimates, at parametric values other than those tested, of present grid set designs. Although argon was the main test gas used in this study, it is shown that the results are applicable to other propellants as well.

  10. Progress Towards Doubling the Beam Power at Fermilab's Accelerator Complex

    SciTech Connect

    Kourbanis, ioanis

    2014-06-01

    After a 14 month shutdown accelerator modifications and upgrades are in place to allow us doubling of the Main Injector beam power. We will discuss the past MI high power operation and the current progress towards doubling the power.

  11. Multiple beam induction accelerators for heavy ion fusion

    NASA Astrophysics Data System (ADS)

    Seidl, Peter A.; Barnard, John J.; Faltens, Andris; Friedman, Alex; Waldron, William L.

    2014-01-01

    Induction accelerators are appealing for heavy-ion driven inertial fusion energy (HIF) because of their high efficiency and their demonstrated capability to accelerate high beam current (?10 kA in some applications). For the HIF application, accomplishments and challenges are summarized. HIF research and development has demonstrated the production of single ion beams with the required emittance, current, and energy suitable for injection into an induction linear accelerator. Driver scale beams have been transported in quadrupole channels of the order of 10% of the number of quadrupoles of a driver. We review the design and operation of induction accelerators and the relevant aspects of their use as drivers for HIF. We describe intermediate research steps that would provide the basis for a heavy-ion research facility capable of heating matter to fusion relevant temperatures and densities, and also to test and demonstrate an accelerator architecture that scales well to a fusion power plant.

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

    SciTech Connect

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

    2010-01-01

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

  13. Experimental characterization of a coaxial plasma accelerator for a colliding plasma experiment

    SciTech Connect

    Wiechula, J.; Hock, C.; Iberler, M.; Manegold, T.; Schönlein, A.; Jacoby, J.

    2015-04-15

    We report experimental results of a single coaxial plasma accelerator in preparation for a colliding plasma experiment. The utilized device consisted of a coaxial pair of electrodes, accelerating the plasma due to J×B forces. A pulse forming network, composed of three capacitors connected in parallel, with a total capacitance of 27 μF was set up. A thyratron allowed to switch the maximum applied voltage of 9 kV. Under these conditions, the pulsed currents reached peak values of about 103 kA. The measurements were performed in a small vacuum chamber with a neutral-gas prefill at gas pressures between 10 Pa and 14 000 Pa. A gas mixture of ArH{sub 2} with 2.8% H{sub 2} served as the discharge medium. H{sub 2} was chosen in order to observe the broadening of the H{sub β} emission line and thus estimate the electron density. The electron density for a single plasma accelerator reached peak values on the order of 10{sup 16} cm{sup −3}. Electrical parameters, inter alia inductance and resistance, were determined for the LCR circuit during the plasma acceleration as well as in a short circuit case. Depending on the applied voltage, the inductance and resistance reached values ranging from 194 nH to 216 nH and 13 mΩ to 23 mΩ, respectively. Furthermore, the plasma velocity was measured using a fast CCD camera. Plasma velocities of 2 km/s up to 17 km/s were observed, the magnitude being highly correlated with gas pressure and applied voltage.

  14. Experimental characterization of a coaxial plasma accelerator for a colliding plasma experiment

    NASA Astrophysics Data System (ADS)

    Wiechula, J.; Hock, C.; Iberler, M.; Manegold, T.; Schnlein, A.; Jacoby, J.

    2015-04-01

    We report experimental results of a single coaxial plasma accelerator in preparation for a colliding plasma experiment. The utilized device consisted of a coaxial pair of electrodes, accelerating the plasma due to J B forces. A pulse forming network, composed of three capacitors connected in parallel, with a total capacitance of 27 ?F was set up. A thyratron allowed to switch the maximum applied voltage of 9 kV. Under these conditions, the pulsed currents reached peak values of about 103 kA. The measurements were performed in a small vacuum chamber with a neutral-gas prefill at gas pressures between 10 Pa and 14 000 Pa. A gas mixture of ArH2 with 2.8% H2 served as the discharge medium. H2 was chosen in order to observe the broadening of the H? emission line and thus estimate the electron density. The electron density for a single plasma accelerator reached peak values on the order of 1016 cm-3 . Electrical parameters, inter alia inductance and resistance, were determined for the LCR circuit during the plasma acceleration as well as in a short circuit case. Depending on the applied voltage, the inductance and resistance reached values ranging from 194 nH to 216 nH and 13 m? to 23 m?, respectively. Furthermore, the plasma velocity was measured using a fast CCD camera. Plasma velocities of 2 km/s up to 17 km/s were observed, the magnitude being highly correlated with gas pressure and applied voltage.

  15. Plasma accelerators

    SciTech Connect

    Ruth, R.D.; Chen, P.

    1986-03-01

    In this paper we discuss plasma accelerators which might provide high gradient accelerating fields suitable for TeV linear colliders. In particular we discuss two types of plasma accelerators which have been proposed, the Plasma Beat Wave Accelerator and the Plasma Wake Field Accelerator. We show that the electric fields in the plasma for both schemes are very similar, and thus the dynamics of the driven beams are very similar. The differences appear in the parameters associated with the driving beams. In particular to obtain a given accelerating gradient, the Plasma Wake Field Accelerator has a higher efficiency and a lower total energy for the driving beam. Finally, we show for the Plasma Wake Field Accelerator that one can accelerate high quality low emittance beams and, in principle, obtain efficiencies and energy spreads comparable to those obtained with conventional techniques.

  16. Acceleration of ampere class H(-) ion beam by MeV accelerator.

    PubMed

    Taniguchi, M; Inoue, T; Umeda, N; Kashiwagi, M; Watanabe, K; Tobari, H; Dairaku, M; Sakamoto, K

    2008-02-01

    The H(-) ion accelerator R&D to realize the international thermonuclear experimental reactor neutral beam is ongoing at Japan Atomic Energy Agency (JAEA). The required performance for the prototype MeV accelerator developed at JAEA is 1 MeV, 500 mA (current density of 200 A/m(2)) H(-) ion beam at the beamlet divergence angle of less than 7 mrad. Up to 2005, 836 keV, 146 A/m(2) H(-) ion beam was successfully accelerated as the highest record of the current density at MeV class energy beams. In the present work, high current negative ion beam acceleration test was performed by increasing the beam extraction apertures from 3 x 3 (9 apertures) to 3 x 5 (15 apertures). By fixing the air leak at the source chamber due to backstream ions as well as the improvement of voltage holding capability by a new fiber reinforced plastic insulator ring, the performance of the MeV accelerator was improved. So far, H(-) ion beam of 320 mA was successfully accelerated up to 796 keV with the beam divergence angle of 5.5 mrad. The accelerated drain current including the electron reaches close to the power supply limit for the MeV test facility. The heat flux by the backstream ion during the above beam acceleration was estimated to be 360 W/cm(2). The Cs leakage to the accelerator during the test campaign (Cs total input of 5.0 g) was 0.26 mg (7.0 microg/cm(2)). This is considered to be the allowable level from the viewpoint of voltage holding. PMID:18315236

  17. Ion bunch length effects on the beam-beam interaction and its compensation in a high-luminosity ring-ring electron-ion collider

    SciTech Connect

    Montag C.; Oeftiger, A.; Fischer, W.

    2012-05-20

    One of the luminosity limits in a ring-ring electron-ion collider is the beam-beam effect on the electrons. In the limit of short ion bunches, simulation studies have shown that this limit can be significantly increased by head-on beam-beam compensation with an electron lens. However, with an ion bunch length comparable to the beta-function at the IP in conjunction with a large beam-beam parameter, the electrons perform a sizeable fraction of a betatron oscillation period inside the long ion bunches. We present recent simulation results on the compensation of this beam-beam interaction with multiple electron lenses.

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

    DOEpatents

    Maschke, A.W.

    1984-04-16

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

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

    DOEpatents

    Maschke, Alfred W. (East Moriches, NY)

    1985-01-01

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

  20. Design study of primary ion provider for relativistic heavy ion collider electron beam ion sourcea)

    NASA Astrophysics Data System (ADS)

    Kondo, K.; Kanesue, T.; Tamura, J.; Okamura, M.

    2010-02-01

    Brookhaven National Laboratory has developed the new preinjector system, electron beam ion source (EBIS) for relativistic heavy ion collider (RHIC) and National Aeronautics and Space Administration Space Radiation Laboratory. Design of primary ion provider is an essential problem since it is required to supply beams with different ion species to multiple users simultaneously. The laser ion source with a defocused laser can provide a low charge state and low emittance ion beam, and is a candidate for the primary ion source for RHIC-EBIS. We show a suitable design with appropriate drift length and solenoid, which helps to keep sufficient total charge number with longer pulse length. The whole design of primary ion source, as well as optics arrangement, solid targets configuration and heating about target, is presented.

  1. Tailored electron bunches with smooth current profiles for enhanced transformer ratios in beam-driven acceleration

    NASA Astrophysics Data System (ADS)

    Lemery, F.; Piot, P.

    2015-08-01

    Collinear high-gradient O (GV /m ) beam-driven wakefield methods for charged-particle acceleration could be critical to the realization of compact, cost-efficient, accelerators, e.g., in support of TeV-scale lepton colliders or multiple-user free-electron laser facilities. To make these options viable, the high accelerating fields need to be complemented with large transformer ratios >2 , a parameter characterizing the efficiency of the energy transfer between a wakefield-exciting "drive" bunch to an accelerated "witness" bunch. While several potential current distributions have been discussed, their practical realization appears challenging due to their often discontinuous nature. In this paper we propose several alternative continuously differentiable (smooth) current profiles which support enhanced transformer ratios. We especially demonstrate that one of the devised shapes can be implemented in a photo-emission electron source by properly shaping the photocathode-laser pulse. We finally discuss a possible superconducting linear-accelerator concept that could produce shaped drive bunches at high-repetition rates to drive a dielectric-wakefield accelerator with accelerating fields on the order of ˜60 MV /m and a transformer ratio ˜5 consistent with a recently proposed multiuser free-electron laser facility.

  2. Design of an 18 MW vortex flow water beam dump for 500 GeV electrons/positrons of an international linear collider

    NASA Astrophysics Data System (ADS)

    Satyamurthy, Polepalle; Rai, Pravin; Tiwari, Vikas; Kulkarni, Kiran; Amann, John; Arnold, Raymond G.; Walz, Dieter; Seryi, Andrei; Davenne, Tristan; Caretta, Ottone; Densham, Chris; Appleby, Robert B.

    2012-07-01

    Beam dumps are essential components of any accelerator system. They are usually located at the end of the beam delivery systems and are designed to safely absorb and dissipate the particle energy. In the second stage of the proposed International Linear Collider (ILC), the electron and positron beams are accelerated to 500 GeV each (1 TeV total). Each bunch will have 21010 electrons/positrons, and 2820 bunches form one beam bunch train with time duration of 0.95 ms and 4 Hz frequency. The average beam power will be 18 MW with a peak power of 4.5 GW. The FLUKA code was used to determine the power deposited by the beam at all critical locations. This data forms the input into the thermal hydraulic analysis CFD code for detailed flow and thermal evaluation. Both 2D and 3D flow analyses were carried out at all the critical regions to arrive at optimum geometry and flow parameters of the beam dump. The generation and propagation of pressure waves due to rapid deposition of heat has also been analyzed.

  3. Beam dynamics simulations of post low energy beam transport section in RAON heavy ion accelerator

    NASA Astrophysics Data System (ADS)

    Jin, Hyunchang; Jang, Ji-Ho; Jang, Hyojae; Hong, In-Seok

    2016-02-01

    RAON (Rare isotope Accelerator Of Newness) heavy ion accelerator of the rare isotope science project in Daejeon, Korea, has been designed to accelerate multiple-charge-state beams to be used for various science programs. In the RAON accelerator, the rare isotope beams which are generated by an isotope separation on-line system with a wide range of nuclei and charges will be transported through the post Low Energy Beam Transport (LEBT) section to the Radio Frequency Quadrupole (RFQ). In order to transport many kinds of rare isotope beams stably to the RFQ, the post LEBT should be devised to satisfy the requirement of the RFQ at the end of post LEBT, simultaneously with the twiss parameters small. We will present the recent lattice design of the post LEBT in the RAON accelerator and the results of the beam dynamics simulations from it. In addition, the error analysis and correction in the post LEBT will be also described.

  4. Beam losses and beam halos in accelerators for new energy sources

    SciTech Connect

    Jameson, R.A.

    1995-12-31

    Large particle accelerators are proposed as drivers for new ways to produce electricity from nuclear fusion and fission reactions. The accelerators must be designed to deliver large particle beam currents to a target facility with very little beam spill along the accelerator itself, in order that accelerator maintenance can be accomplished without remote manipulators. Typically, particle loss is preceded by the formation of a tenuous halo of particles around the central beam core, caused by beam dynamics effects, often coupled with the slight imperfections inevitable in a practical design. If the halo becomes large enough, particles may be scraped off along the accelerator. The tolerance for beam spill in different applications is discussed, halo mechanisms and recent work to explore and understand their dynamics are reviewed, and possible directions for future investigation are outlined. 17 refs., 10 figs.

  5. Ablative Rayleigh-Taylor and Richtmyer-Meshkov Instabilities in Laser-Accelerated Colliding Foils

    NASA Astrophysics Data System (ADS)

    Aglitskiy, Y.; Metzler, N.; Karasik, M.; Serlin, V.; Weaver, J.; Obenschain, S. P.; Oh, J.; Schmitt, A. J.; Velikovich, A. L.; Zalesak, S. T.; Gardner, J. H.; Harding, E. C.

    2008-11-01

    In our experiments done on the Nike KrF laser, we study instability growth at shock-decelerated interfaces in planar colliding-foil experiments. We use streaked monochromatic (1.86 keV) x-ray face-on imaging diagnostics to measure the areal mass modulation growth caused by the instability. Higher x-ray energies up to 5.25 keV are used to follow the shock propagation as well as the 1D dynamics of the collision. While a laser-driven foil is accelerated towards the stationary low-density foam layer, an ablative RT instability develops. Having reached a high velocity, the foil hits the foam layer. The impact generates strong shocks in the plastic and in the foam. The reflected shock wave re-shocks the ablation front, its acceleration stops, and so does the observed RT growth. This is followed by areal mass oscillations due to the ablative RM instability and feedout mechanisms, of which the latter dominates.

  6. Efficient Optical Energy Harvesting in Self-Accelerating Beams

    PubMed Central

    Bongiovanni, Domenico; Hu, Yi; Wetzel, Benjamin; Robles, Raul A.; Mendoza González, Gregorio; Marti-Panameño, Erwin A.; Chen, Zhigang; Morandotti, Roberto

    2015-01-01

    We report the experimental observation of energetically confined self-accelerating optical beams propagating along various convex trajectories. We show that, under an appropriate transverse compression of their spatial spectra, these self-accelerating beams can exhibit a dramatic enhancement of their peak intensity and a significant decrease of their transverse expansion, yet retaining both the expected acceleration profile and the intrinsic self-healing properties. We found our experimental results to be in excellent agreement with the numerical simulations. We expect further applications in such contexts where power budget and optimal spatial confinement can be important limiting factors. PMID:26299360

  7. Efficient Optical Energy Harvesting in Self-Accelerating Beams

    NASA Astrophysics Data System (ADS)

    Bongiovanni, Domenico; Hu, Yi; Wetzel, Benjamin; Robles, Raul A.; Mendoza Gonzlez, Gregorio; Marti-Panameo, Erwin A.; Chen, Zhigang; Morandotti, Roberto

    2015-08-01

    We report the experimental observation of energetically confined self-accelerating optical beams propagating along various convex trajectories. We show that, under an appropriate transverse compression of their spatial spectra, these self-accelerating beams can exhibit a dramatic enhancement of their peak intensity and a significant decrease of their transverse expansion, yet retaining both the expected acceleration profile and the intrinsic self-healing properties. We found our experimental results to be in excellent agreement with the numerical simulations. We expect further applications in such contexts where power budget and optimal spatial confinement can be important limiting factors.

  8. High transformer ratio drive beams for wakefield accelerator studies

    NASA Astrophysics Data System (ADS)

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

    2012-12-01

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

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

    Energy Science and Technology Software Center (ESTSC)

    2006-08-01

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

  10. A laser-plasma accelerator producing monoenergetic electron beams.

    PubMed

    Faure, J; Glinec, Y; Pukhov, A; Kiselev, S; Gordienko, S; Lefebvre, E; Rousseau, J-P; Burgy, F; Malka, V

    2004-09-30

    Particle accelerators are used in a wide variety of fields, ranging from medicine and biology to high-energy physics. The accelerating fields in conventional accelerators are limited to a few tens of MeV m(-1), owing to material breakdown at the walls of the structure. Thus, the production of energetic particle beams currently requires large-scale accelerators and expensive infrastructures. Laser-plasma accelerators have been proposed as a next generation of compact accelerators because of the huge electric fields they can sustain (>100 GeV m(-1)). However, it has been difficult to use them efficiently for applications because they have produced poor-quality particle beams with large energy spreads, owing to a randomization of electrons in phase space. Here we demonstrate that this randomization can be suppressed and that the quality of the electron beams can be dramatically enhanced. Within a length of 3 mm, the laser drives a plasma bubble that traps and accelerates plasma electrons. The resulting electron beam is extremely collimated and quasi-monoenergetic, with a high charge of 0.5 nC at 170 MeV. PMID:15457253

  11. Transformer ratio improvement for beam based plasma accelerators

    SciTech Connect

    O'Shea, Brendan; Rosenzweig, James; Barber, Samuel; Fukasawa, Atsushi; Williams, Oliver; Muggli, Patric; Yakimenko, Vitaly; Kusche, Karl

    2012-12-21

    Increasing the transformer ratio of wakefield accelerating systems improves the viability of present novel accelerating schemes. The use of asymmetric bunches to improve the transformer ratio of beam based plasma systems has been proposed for some time[1, 2] but suffered from lack appropriate beam creation systems. Recently these impediments have been overcome [3, 4] and the ability now exists to create bunches with current profiles shaped to overcome the symmetric beam limit of R {<=} 2. We present here work towards experiments designed to measure the transformer ratio of such beams, including theoretical models and simulations using VORPAL (a 3D capable PIC code) [5]. Specifically we discuss projects to be carried out in the quasi-nonlinear regime [6] at the UCLA Neptune Laboratory and the Accelerator Test Facility at Brookhaven National Lab.

  12. Cold- and Beam Test of the First Prototypes of the Superstructure for the TESLA Collider

    SciTech Connect

    Baboi, Nicoleta

    2003-08-08

    After three years of preparation, two superstructures, each made of two superconducting 7-cell weakly coupled subunits, have been installed in the TESLA Test Facility linac (TTF) for the cold- and beam-test. The energy stability, the HOMs damping, the frequency and the field adjustment methods were tested. The measured results confirmed expectation on the superstructure performance and proved that alternative layout for the 800 GeV upgrade of the TESLA collider, as it was proposed in TDR, is feasible. We report on the test and give here an overview of its results which are commented in more detail elsewhere in these Proceedings.

  13. Search for magnetic fields in particle-accelerating colliding-wind binaries

    NASA Astrophysics Data System (ADS)

    Neiner, C.; Grunhut, J.; Leroy, B.; De Becker, M.; Rauw, G.

    2015-03-01

    Context. Some colliding-wind massive binaries, called particle-accelerating colliding-wind binaries (PACWB), exhibit synchrotron radio emission, which is assumed to be generated by a stellar magnetic field. However, no measurement of magnetic fields in these stars has ever been performed. Aims: We aim at quantifying the possible stellar magnetic fields present in PACWB to provide constraints for models. Methods: We gathered 21 high-resolution spectropolarimetric observations of 9 PACWB available in the ESPaDOnS, Narval and HarpsPol archives. We analysed these observations with the least squares deconvolution method. We separated the binary spectral components when possible. Results: No magnetic signature is detected in any of the 9 PACWB stars and all longitudinal field measurements are compatible with 0 G. We derived the upper field strength of a possible field that could have remained hidden in the noise of the data. While the data are not very constraining for some stars, for several stars we could derive an upper limit of the polar field strength of the order of 200 G. Conclusions: We can therefore exclude the presence of strong or moderate stellar magnetic fields in PACWB, typical of the ones present in magnetic massive stars. Weak magnetic fields could however be present in these objects. These observational results provide the first quantitative constraints for future models of PACWB. Based on archival observations obtained at the Tlescope Bernard Lyot (USR5026) operated by the Observatoire Midi-Pyrnes, Universit de Toulouse (Paul Sabatier), Centre National de la Recherche Scientifique (CNRS) of France, at the Canada-France-Hawaii Telescope (CFHT) operated by the National Research Council of Canada, the Institut National des Sciences de l'Univers of the CNRS of France, and the University of Hawaii, and at the European Southern Observatory (ESO), Chile.

  14. Particle-beam accelerators for radiotherapy and radioisotopes

    NASA Astrophysics Data System (ADS)

    Boyd, T. J., Jr.; Crandall, K. R.; Hamm, R. W.; Hansborough, L. D.; Hoeberling, R. F.; Jameson, R. A.; Knapp, E. A.; Mueller, D. W.; Potter, J. M.; Stokes, R. H.

    The philosophy used in developing the PIGMI (pion generator for medical irradiation) technology was that the parameters chosen for physics research machines are not necessarily the right ones for a dedicated therapy or radioisotope machine. In particular, the beam current and energy can be optimized, and the design should emphasize minimum size, simplicity and reliability of operation, and economy in capital and operating costs. A major part of achieving these goals lay in raising the operating frequency and voltage gradient of the accelerator, which shrinks the diameter and length of the components. Several other technical innovations resulted in major system improvements. One of these is a radically new type of accelerator structure named the radio frequency quadrupole accelerator. This allowed the elimination of the large, complicated ion source used in previous ion accelerators, and a very high quality accelerated beam. Also, by using advanced permanent magnet materials to make the focusing elements, the system becomes much simpler. Other improvements are described.

  15. Muon colliders

    SciTech Connect

    Palmer, R.B. |; Sessler, A.; Skrinsky, A.

    1996-01-01

    Muon Colliders have unique technical and physics advantages and disadvantages when compared with both hadron and electron machines. They should thus be regarded as complementary. Parameters are given of 4 TeV and 0.5 TeV high luminosity {micro}{sup +}{micro}{sup {minus}}colliders, and of a 0.5 TeV lower luminosity demonstration machine. We discuss the various systems in such muon colliders, starting from the proton accelerator needed to generate the muons and proceeding through muon cooling, acceleration and storage in a collider ring. Problems of detector background are also discussed.

  16. Coherent beam-beam effects observation and mitigation at the RHIC collider

    SciTech Connect

    White S.; Fischer, W.; Luo, Y.

    2012-05-20

    In polarized proton operation in RHIC coherent beam-beam modes are routinely observed with beam transfer function measurements in the vertical plane. With the existence of coherent modes a larger space is required in the tune diagram than without them and stable conditions can be compromised for operation with high intensity beams as foreseen for future luminosity upgrades. We report on experiments and simulations carried out to understand the existence of coherent modes in the vertical plane and their absence in the horizontal plane, and investigate possible mitigation strategies.

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

    NASA Astrophysics Data System (ADS)

    Xiang, W.; Tang, P. Y.

    2006-03-01

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

  18. High efficiency beam splitting for H/sup -/ accelerators

    SciTech Connect

    Kramer, S.L.; Stipp, V.; Krieger, C.; Madsen, J.

    1985-01-01

    Beam splitting for high energy accelerators has typically involved a significant loss of beam and radiation. This paper reports on a new method of splitting beams for H/sup -/ accelerators. This technique uses a high intensity flash of light to strip a fraction of the H/sup -/ beam to H/sup 0/ which are then easily separated by a small bending magnet. A system using a 900-watt (average electrical power) flashlamp and a highly efficient collector will provide 10/sup -3/ to 10/sup -2/ splitting of a 50 MeV H/sup -/ beam. Results on the operation and comparisons with stripping cross sections are presented. Also discussed is the possibility for developing this system to yield a higher stripping fraction.

  19. CCD based beam loss monitor for ion accelerators

    NASA Astrophysics Data System (ADS)

    Belousov, A.; Mustafin, E.; Ensinger, W.

    2014-04-01

    Beam loss monitoring is an important aspect of proper accelerator functioning. There is a variety of existing solutions, but each has its own disadvantages, e.g. unsuitable dynamic range or time resolution, high cost, or short lifetime. Therefore, new options are looked for. This paper shows a method of application of a charge-coupled device (CCD) video camera as a beam loss monitor (BLM) for ion beam accelerators. The system was tested with a 500 MeV/u N+7 ion beam interacting with an aluminum target. The algorithms of camera signal processing with LabView based code and beam loss measurement are explained. Limits of applicability of this monitor system are discussed.

  20. Fast Ignition by Photon-Pressure Accelerated Ion Beam

    NASA Astrophysics Data System (ADS)

    Johzaki, Tomoyuki; Sentoku, Yasuhiko; Sunahara, Atsushi; Morikawa, Takamasa; Endo, Takuma

    2014-10-01

    For enhancing the core heating efficiency in fast ignition, the ion beam generated by radiative pressure acceleration with circularly-polarized ultra-intense laser pulse is used as a core heating driver. In the present study, on the basis of the integrated simulations (PIC simulations for beam generation and Fokker-Planck simulations for core heating) and demonstrated the potential probability for C6+ beam driven fast ignition. From the coupled transport and hydro simulations, it is found that the beam particle (C6+) energy of 100 ~ 200 MeV minimizes the beam energy required for ignition and the beam duration of ~1 ps is suitable for ignition in terms of beam generation and core heating. From 2D PIC simulations for ion beam generation it is found that fast ion beam with ion energy of 210 MeV is obtained when the carbon target with the ion density of 90 ncr (ncr is the laser critical density) is irradiated with the CP laser with the intensity of 6×1022 W/cm2. In this case, 12% energy convergence efficiency of laser to ion beam is obtained. If assuming the laser spot of 24 micron diameter and pulse duration of 700 fs, the required laser energy for beam generation is ~190 kJ and the resultant beam energy of 23 kJ, which satisfy the beam condition required for ignition.

  1. Long-pulse beam acceleration of MeV-class H(-) ion beams for ITER NB accelerator.

    PubMed

    Umeda, N; Kashiwagi, M; Taniguchi, M; Tobari, H; Watanabe, K; Dairaku, M; Yamanaka, H; Inoue, T; Kojima, A; Hanada, M

    2014-02-01

    In order to realize neutral beam systems in International Thermonuclear Experimental Reactor whose target is to produce a 1 MeV, 200 A/m(2) during 3600 s D(-) ion beam, the electrostatic five-stages negative ion accelerator so-called "MeV accelerator" has been developed at Japan Atomic Energy Agency. To extend pulse length, heat load of the acceleration grids was reduced by controlling the ion beam trajectory. Namely, the beam deflection due to the residual magnetic field of filter magnet was suppressed with the newly developed extractor with a 0.5 mm off-set aperture displacement. The new extractor improved the deflection angle from 6 mrad to 1 mrad, resulting in the reduction of direct interception of negative ions from 23% to 15% of the total acceleration power, respectively. As a result, the pulse length of 130 A/m(2), 881 keV H(-) ion beam has been successfully extended from a previous value of 0.4 s to 8.7 s. This is the first long pulse negative ion beam acceleration over 100 MW/m(2). PMID:24593581

  2. Long pulse H- ion beam acceleration in MeV accelerator.

    PubMed

    Taniguchi, M; Mizuno, T; Umeda, N; Kashiwagi, M; Watanabe, K; Tobari, H; Kojima, A; Tanaka, Y; Dairaku, M; Hanada, M; Sakamoto, K; Inoue, T

    2010-02-01

    A multiaperture multigrid accelerator called "MeV accelerator" has been developed for neutral beam injection system of international thermonuclear experimental reactor. In the present work, long pulse H(-) ion beam acceleration was performed by the MeV accelerator equipped with new water-cooled grids. At present, the pulse length was extended to 5 s for the beams of 750 keV, 221 mA, and 10 s for the beams of 600 keV, 158 mA. Energy density, defined as products of beam energy (keV), current (mA), and pulse (s) divided by aperture area (m(2)), increased more than one order of magnitude higher compared with original MeV accelerator without water cooling in its grids. At higher energy and current, the grid was melted by beam deflection. Due to this grid melting, breakdowns occurred between the grids, and hence, the pulse length was limited. Beam deflection will be compensated by aperture displacement in next experiment. PMID:20192408

  3. Long pulse H{sup -} ion beam acceleration in MeV accelerator

    SciTech Connect

    Taniguchi, M.; Mizuno, T.; Umeda, N.; Kashiwagi, M.; Watanabe, K.; Tobari, H.; Kojima, A.; Tanaka, Y.; Dairaku, M.; Hanada, M.; Sakamoto, K.; Inoue, T.

    2010-02-15

    A multiaperture multigrid accelerator called ''MeV accelerator'' has been developed for neutral beam injection system of international thermonuclear experimental reactor. In the present work, long pulse H{sup -} ion beam acceleration was performed by the MeV accelerator equipped with new water-cooled grids. At present, the pulse length was extended to 5 s for the beams of 750 keV, 221 mA, and 10 s for the beams of 600 keV, 158 mA. Energy density, defined as products of beam energy (keV), current (mA), and pulse (s) divided by aperture area (m{sup 2}), increased more than one order of magnitude higher compared with original MeV accelerator without water cooling in its grids. At higher energy and current, the grid was melted by beam deflection. Due to this grid melting, breakdowns occurred between the grids, and hence, the pulse length was limited. Beam deflection will be compensated by aperture displacement in next experiment.

  4. Beam transport and monitoring for laser plasma accelerators

    SciTech Connect

    Nakamura, K.; Sokollik, T.; Tilborg, J. van; Gonsalves, A. J.; Shaw, B.; Shiraishi, S.; Mittal, R.; De Santis, S.; Byrd, J. M.; Leemans, W.

    2012-12-21

    The controlled transport and imaging of relativistic electron beams from laser plasma accelerators (LPAs) are critical for their diagnostics and applications. Here we present the design and progress in the implementation of the transport and monitoring system for an undulator based electron beam diagnostic. Miniature permanent-magnet quadrupoles (PMQs) are employed to realize controlled transport of the LPA electron beams, and cavity based electron beam position monitors for non-invasive beam position detection. Also presented is PMQ calibration by using LPA electron beams with broadband energy spectrum. The results show promising performance for both transporting and monitoring. With the proper transport system, XUV-photon spectra from THUNDER will provide the momentum distribution of the electron beam with the resolution above what can be achieved by the magnetic spectrometer currently used in the LOASIS facility.

  5. Accelerator Based Neutron Beams for Neutron Capture Therapy

    SciTech Connect

    Yanch, Jacquelyn C.

    2003-04-11

    The DOE-funded accelerator BNCT program at the Massachusetts Institute of Technology has resulted in the only operating accelerator-based epithermal neutron beam facility capable of generating significant dose rates in the world. With five separate beamlines and two different epithermal neutron beam assemblies installed, we are currently capable of treating patients with rheumatoid arthritis in less than 15 minutes (knee joints) or 4 minutes (finger joints) or irradiating patients with shallow brain tumors to a healthy tissue dose of 12.6 Gy in 3.6 hours. The accelerator, designed by Newton scientific Incorporated, is located in dedicated laboratory space that MIT renovated specifically for this project. The Laboratory for Accelerator Beam Applications consists of an accelerator room, a control room, a shielded radiation vault, and additional laboratory space nearby. In addition to the design, construction and characterization of the tandem electrostatic accelerator, this program also resulted in other significant accomplishments. Assemblies for generating epithermal neutron beams were designed, constructed and experimentally evaluated using mixed-field dosimetry techniques. Strategies for target construction and target cooling were implemented and tested. We demonstrated that the method of submerged jet impingement using water as the coolant is capable of handling power densities of up to 6 x 10(sup 7) W/m(sup 2) with heat transfer coefficients of 10(sup 6)W/m(sup 2)-K. Experiments with the liquid metal gallium demonstrated its superiority compared with water with little effect on the neutronic properties of the epithermal beam. Monoenergetic proton beams generated using the accelerator were used to evaluate proton RBE as a function of LET and demonstrated a maximum RBE at approximately 30-40 keV/um, a finding consistent with results published by other researchers. We also developed an experimental approach to biological intercomparison of epithermal beams and compared the RBE characteristics of the MIT Reactor M67 clinical beam, The Brookhaven Medical Research Reactor clinical beam (both of which were used in Phase I/II clinical trials of BNCT) and the MIT LABA BNCS beam. Additional research initiated under this program involved an investigation of the potential of BNCT for the prevention of restenosis and the development of accelerator-based fast neutron brachytherapy. A total of 10 student research theses (2 Undergraduate, 4 Masters, and 4 Doctoral) were completed as part of this research program.

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

    DOE PAGESBeta

    Shin, Young-Min

    2014-09-15

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

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

    SciTech Connect

    Shin, Young-Min

    2014-09-15

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

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

    SciTech Connect

    Shin, Young-Min

    2014-09-15

    Accelerating parameters of beam-driven wakefield acceleration in an extremely dense plasma column has been analyzed with the dynamic framed particle-in-cell plasma simulator, and compared with analytic calculations. In the model, a witness beam undergoes a TeV/m scale alternating potential gradient excited by a micro-bunched drive beam in a 10{sup 25?}m{sup ?3} and 1.6??10{sup 28?}m{sup ?3} plasma column. The acceleration gradient, energy gain, and transformer ratio have been extensively studied in quasi-linear, linear-, and blowout-regimes. The simulation analysis indicated that in the beam-driven acceleration system a hollow plasma channel offers ?20% higher acceleration gradient by enlarging the channel radius (r) from 0.2 ?{sub p} to 0.6 ?{sub p} in a blowout regime. This paper suggests a feasibility of TeV/m scale acceleration with a hollow crystalline structure (e.g., nanotubes) of high electron plasma density.

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

    SciTech Connect

    Shin, Young-Min

    2014-09-15

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

  10. Accidental beam loss in superconducting accelerators: Simulations, consequences of accidents and protective measures

    SciTech Connect

    Drozhdin, A.; Mokhov, N.; Parker, B.

    1994-02-01

    The consequences of an accidental beam loss in superconducting accelerators and colliders of the next generation range from the mundane to rather dramatic, i.e., from superconducting magnet quench, to overheating of critical components, to a total destruction of some units via explosion. Specific measures are required to minimize and eliminate such events as much as practical. In this paper we study such accidents taking the Superconducting Supercollider complex as an example. Particle tracking, beam loss and energy deposition calculations were done using the realistic machine simulation with the Monte-Carlo codes MARS 12 and STRUCT. Protective measures for minimizing the damaging effects of prefire and misfire of injection and extraction kicker magnets are proposed here.

  11. Beam-induced Electron Loading Effects in High Pressure Cavities for a Muon Collider

    SciTech Connect

    Chung, M.; Tollestrup, A.; Jansson, A.; Yonehara, K.; Insepov, Z.

    2010-05-01

    Ionization cooling is a critical building block for the realization of a muon collider. To suppress breakdown in the presence of the external magnetic field, an idea of using an RF cavity filled with high pressure hydrogen gas is being considered for the cooling channel design. One possible problem expected in the high pressure RF cavity is, however, the dissipation of significant RF power through the beam-induced electrons accumulated inside the cavity. To characterize this detrimental loading effect, we develop a simplified model that relates the electron density evolution and the observed pickup voltage signal in the cavity, with consideration of several key molecular processes such as the formation of the polyatomic molecules, recombination and attachment. This model is expected to be compared with the actual beam test of the cavity in the MuCool Test Area (MTA) of Fermilab.

  12. Polarized antiproton beam at U-70 accelerator of IHEP

    NASA Astrophysics Data System (ADS)

    Nurushev, S. B.; Chetvertkov, M. A.; Chetvertkova, V. A.; Garkusha, V. I.; Meschanin, A. P.; Mochalov, V. V.; Nurusheva, M. B.; Rykov, V. L.; Semenov, P. A.; Strikhanov, M. N.; Vasiliev, A. N.; Zapolsky, V. N.

    2016-02-01

    The polarized proton and antiproton beam channel is currently under development at the U-70 accelerator of IHEP, Protvino, Russia. An availability of the both, polarized protons and antiprotons provides an exciting opportunity for the comparative studies of spin effects induced by polarized protons and antiprotons in a variety of hadronic reactions. While the proton and antiproton beams are formed by essentially the same method, there is the specific in the antiproton beam shaping and properties compared to protons. In this report, we address some technical details of forming the polarized antiproton beam and describe its main properties.

  13. ALPI Setup as the SPES Accelerator of Exotic Beams

    NASA Astrophysics Data System (ADS)

    Bisoffi, G.; Bassato, G.; Battistella, A.; Bermudez, J.; Bortolato, D.; Canella, S.; Chalykh, B.; Comunian, M.; Facco, A.; Fagotti, E.; Galat, A.; Giacchini, M.; Gramegna, F.; Lamy, T.; Modanese, P.; Palmieri, A.; Pengo, R.; Pisent, A.; Poggi, M.; Porcellato, A.; Roncolato, C.; Scarpa, D.

    2014-03-01

    The SPES (Selective Production of Exotic Species) project for a national exotic beam facility in Legnaro includes pivotal upgrades of the existing superconducting linac ALPI (Acceleratore Lineare Per Ioni), to make it appropriate as the RIB (Radioactive Ion Beam) accelerator. The new injector, consisting of an Electron Cyclotron Resonance (ECR)-type charge breeder and a radiofrequency quadrupole (RFQ), will be described. Upgrade measures in ALPI to improve beam transmission and final energy, and handle low-intensity RIB will be explained, with the aim of increasing transmission to T > 90%, Ef by ~ 20%, reaching 10 MeV/u for the reference beam 132Sn.

  14. Transverse Resistive Wall Instability in the Two-Beam Accelerator

    SciTech Connect

    Whittum, D.H.; Sessler, Andrew M.; Neil, V.K.

    1990-06-01

    The transverse resistive wall instability in the Two-Beam Accelerator (TBA) is investigated analytically and numerically. Without any damping mechanism, we find one to four e-folds in 100 m, depending on the design. It is found that Landau damping, due to energy spread within a beam slice, is not effective, due to rapid synchrotron oscillations in the FEL ponderomotive well. Damping due to an energy sweep along the beam is also considered and it is found that a small variation in energy along the beam, decreasing from head to tail, can significantly reduce growth. We conclude that the resistive wall instability is not a severe design constraint on a TBA.

  15. Error-induced beam degradation in Fermilab's accelerators

    NASA Astrophysics Data System (ADS)

    Yong, Sung-Yong Phil

    In Part I, three independent models of Fermilab's Booster synchrotron are presented. All three models are constructed to investigate and to explore the effects of unavoidable machine errors on a proton beam under the influence of space-charge effects. The first is a stochastic noise model. Electric current fluctuations arising from power supplies are ubiquitous and unavoidable and are a source of instabilities in accelerators of all types. A new noise module for generating the Ornstein-Uhlenbeck (O-U) stochastic noise is first created and incorporated into the existing Object-oriented Ring Beam Injection and Tracking (ORBIT-FNAL) package. After being convinced that the noise does matter to a beam with a preliminary model, we proceed to measure directly current ripples and common-mode voltages from all four Gradient Magnet Power Supplies (GMPS). Then, the current signals are Fourier-analyzed. Based upon the power spectra of current signals, we tune up the Ornstein-Uhlnbeck noise model. As a result, we are able to closely match the frequency spectra between current measurements and the modeled O-U stochastic noise. The stochastic noise modeled upon measurements is applied to the Booster beam in the presence of the full space-charge effects. This noise model, accompanied by a suite of beam diagnostic calculations, manifests that the stochastic noise, impinging upon the beam and coupled to the space-charge effects, can substantially enhance the beam degradation process throughout the injection period. The second model is a magnet misalignment model. It is the first time to utilize the latest beamline survey data for building a magnet-by-magnet misalignment model. Given as-found survey fiducial coordinates, we calculate all types of magnet alignment errors (station error, pitch, yaw, roll, twists, etc.) are implemented in the model. We then follow up with statistical analysis to understand how each type of alignment errors are currently distributed around the Booster ring. The ORBIT-FNAL simulations with space charge included show that rolled magnets, in particular, have substantial effects on the Booster beam. This survey-data-based misalignment model can predict how much improvement in machine performance can be achieved if prioritized or selected realignment work is done. In other words, this model can help us investigate different realignment scenarios for the Booster. In addition, by calculating average angular kicks from all misaligned magnets, we expect this misalignment model to serve as guidelines for resetting the strengths of corrector magnets. The third model for the Booster is a time-structured multi-turn injection model. Microbunch-injection scenarios with different time structures are explored in the presence of longitudinal space-charge force. Due to the radio-frequency (RF) bucket mismatch between the Booster and the 400-MeV transferline, RF-phase offsets can be parasitically introduced during the injection process. Using the microbunch multi-turn injection, we carry out ESME-ORBIT combined simulations. This combined simulation allows us to investigate realistic charge-density distribution under full space-charge effects. The growth rates of transverse emittances turned out to be 20% in both planes. This microbunch-injection scenarios is also applicable to the future 8-GeV Superconducting Linac Proton Driver and the upgraded Main Injector at Fermilab. In Part II, the feasibility of momentum-stacking method of proton beams is investigated. When the Run2 collider program at Fermilab is terminated around year 2009, the present antiproton source can be available for other purposes. One possible application is to convert the antiproton accumulator to a proton accumulator, so that the beam power from the Main Injector could be enhanced by a factor of four. Through adiabatic processes and optimized parameters of synchrotron motion, we demonstrate with an aid of the ESME code that up to four proton batches can be stacked in the momentum acceptance available for the Accumulator ring. This momentum-stacking method is expected to be a part of Fermilab's SuperNuMI (SNuMI) project.

  16. Electron-beam rocket acceleration of hydrogen pellets

    SciTech Connect

    Tsai, C.C.; Foster, C.A.; Milora, S.L.; Schechter, D.E.; Whealton, J.H.

    1992-12-31

    A proof-of-principle device for characterizing electron-beam rocket pellet acceleration has been developed and operated during the last few years. Experimental data have been collected for thousands of accelerated hydrogen pellets under a variety of beam conditions. One intact hydrogen pellet was accelerated to a speed of 578 m/s by an electron beam of 10 kV, 0.8 A, and I ms. The collected data reveal the significant finding that the measured bum velocity of bare hydrogen pellets increases with the square of the beam voltage in a way that is qualitatively consistent with the theoretical prediction based on the neutral gas shielding (NGS) model. The measured bum velocity increases with the beam current or power and then saturates at values two to three times greater than that predicted by the NGS model. The discrepancy may result from low pellet strength and large beam-pellet interaction areas. Moreover, this feature may be the cause of the low measured exhaust velocity, which often exceeds the sonic velocity of the ablated gas. Consistent with the NGS model, the measured exhaust velocity increases in direct proportion to the beam current and in inverse proportion to the beam voltage. To alleviate the pellet strength problem, experiments have been performed with the hydrogen ice contained in a lightweight rocket casing or shell. Pellets in such sabots have the potential to withstand higher beam powers and achieve higher thrust-coupling efficiency. Some experimental results are reported and ways of accelerating pellets to higher velocity are discussed.

  17. Electron-beam rocket acceleration of hydrogen pellets

    SciTech Connect

    Tsai, C.C.; Foster, C.A.; Milora, S.L.; Schechter, D.E.; Whealton, J.H. )

    1993-07-01

    A proof-of-principle device for characterizing electron-beam rocket pellet acceleration has been developed and operated during the last few years. Experimental data have been collected for thousands of accelerated hydrogen pellets under a variety of beam conditions. One intact hydrogen pellet was accelerated to a speed of 578 m/s by an electron beam of 10 kV, 0.8 A, and 1 ms. The collected data reveal the significant finding that the measured burn velocity of bare hydrogen pellets increases with the square of the beam voltage in a way that is qualitatively consistent with the theoretical prediction based on the neutral gas shielding (NGS) model. The measured burn velocity increases with the beam current or power and then saturates at values two to three times greater than that predicted by the NGS model. The discrepancy may result from low pellet strength and large beam-pellet interaction areas. Moreover, this feature may be the cause of the low measured exhaust velocity, which often exceeds the sonic velocity of the ablated gas. Consistent with the NGS model, the measured exhaust velocity increases in direct proportion to the beam current and in inverse proportion to the beam voltage. To alleviate the pellet strength problem, experiments have been performed with the hydrogen ice contained in a lightweight rocket casing or shell. Pellets in such sabots have the potential to withstand higher beam powers and achieve higher thrust-coupling efficiency. Some experimental results are reported and ways of accelerating pellets to higher velocity are discussed.

  18. Electron-beam rocket acceleration of hydrogen pellets

    SciTech Connect

    Tsai, C.C.; Foster, C.A.; Milora, S.L.; Schechter, D.E.; Whealton, J.H.

    1992-01-01

    A proof-of-principle device for characterizing electron-beam rocket pellet acceleration has been developed and operated during the last few years. Experimental data have been collected for thousands of accelerated hydrogen pellets under a variety of beam conditions. One intact hydrogen pellet was accelerated to a speed of 578 m/s by an electron beam of 10 kV, 0.8 A, and I ms. The collected data reveal the significant finding that the measured bum velocity of bare hydrogen pellets increases with the square of the beam voltage in a way that is qualitatively consistent with the theoretical prediction based on the neutral gas shielding (NGS) model. The measured bum velocity increases with the beam current or power and then saturates at values two to three times greater than that predicted by the NGS model. The discrepancy may result from low pellet strength and large beam-pellet interaction areas. Moreover, this feature may be the cause of the low measured exhaust velocity, which often exceeds the sonic velocity of the ablated gas. Consistent with the NGS model, the measured exhaust velocity increases in direct proportion to the beam current and in inverse proportion to the beam voltage. To alleviate the pellet strength problem, experiments have been performed with the hydrogen ice contained in a lightweight rocket casing or shell. Pellets in such sabots have the potential to withstand higher beam powers and achieve higher thrust-coupling efficiency. Some experimental results are reported and ways of accelerating pellets to higher velocity are discussed.

  19. Two-beam, Multi-mode Detuned Accelerating Structure

    SciTech Connect

    Kazakov, S. Yu.; Kuzikov, S. V.; Yakovlev, V. P.; Hirshfield, J. L.

    2009-01-22

    A two-beam accelerator structure is described having several novel features including all metal construction, no transfer structures required between the drive and accelerator channels, symmetric fields at the axes of each channel, RF micropulse widths on cavity irises that are less than half those for a conventional cavity at the same fundamental frequency by virtue of using several harmonically-related cavity modes, and a transformer ratio much greater than unity by the use of detuned cavities. Detuning is also shown to allow either parallel or anti-parallel directions for the drive and accelerated beams. A preliminary calculation for the dilution of emittance due to short-range wakes for drive beam parameters similar to those for CLIC shows this effect to be acceptably small.

  20. Data handling facility for the Sandia Particle Beam Fusion Accelerator

    SciTech Connect

    Boyer, W. B.; Neau, E. L.

    1980-01-01

    This paper describes an on-line data handling facility for Sandia's Particle Beam Fusion Accelerator, PBFA-I, and the upgrade prototype machine Supermite. These accelerators are used for research on inertial confinement fusion (ICF) using particle beams. The main objectives in designing the data acquisition system were: (1) process both experiment and machine performance diagnostic signals, (2) record high signal-to-noise ratio, wideband waveforms in a severe EMP environment, (3) support multiple users recording and analyzing data simultaneously, and (4) provide fast turnaround for experimental results. Commercially available equipment is used wherever possible. However, several special purpose devices were developed. This data handling facility is a significant upgrade of an existing system that supports other Sandia particle beam fusion research accelerators.

  1. Parametric study of transport beam lines for electron beams accelerated by laser-plasma interaction

    NASA Astrophysics Data System (ADS)

    Scisciò, M.; Lancia, L.; Migliorati, M.; Mostacci, A.; Palumbo, L.; Papaphilippou, Y.; Antici, P.

    2016-03-01

    In the last decade, laser-plasma acceleration of high-energy electrons has attracted strong attention in different fields. Electrons with maximum energies in the GeV range can be laser-accelerated within a few cm using multi-hundreds terawatt (TW) lasers, yielding to very high beam currents at the source (electron bunches with up to tens-hundreds of pC in a few fs). While initially the challenge was to increase the maximum achievable electron energy, today strong effort is put in the control and usability of these laser-generated beams that still lack of some features in order to be used for applications where currently conventional, radio-frequency (RF) based, electron beam lines represent the most common and efficient solution. Several improvements have been suggested for this purpose, some of them acting directly on the plasma source, some using beam shaping tools located downstream. Concerning the latter, several studies have suggested the use of conventional accelerator magnetic devices (such as quadrupoles and solenoids) as an easy implementable solution when the laser-plasma accelerated beam requires optimization. In this paper, we report on a parametric study related to the transport of electron beams accelerated by laser-plasma interaction, using conventional accelerator elements and tools. We focus on both, high energy electron beams in the GeV range, as produced on petawatt (PW) class laser systems, and on lower energy electron beams in the hundreds of MeV range, as nowadays routinely obtained on commercially available multi-hundred TW laser systems. For both scenarios, our study allows understanding what are the crucial parameters that enable laser-plasma accelerators to compete with conventional ones and allow for a beam transport. We show that suitable working points require a tradeoff-combination between low beam divergence and narrow energy spread.

  2. Full quantum treatment of spin-dependent beam-beam processes at linear colliders

    NASA Astrophysics Data System (ADS)

    Hartin, Anthony

    2011-05-01

    Depolarisation processes at future linear colliders need to be understood as precisely as possible. To that end a theoretical consideration of the spin flip process and its radiative corrections is presented here. The spin flip process contains a divergence and it is useful to repeat the calculation of its transition rate using a coordinate system which makes the physical nature of the divergence apparent. It is argued that the radiative corrections to the spin flip process should be considered within the Furry Picture. The Electron Self Energy in the external field is being explicitly re-examined in order to establish the presence of UV divergences and the procedure required to remove them. A calculation of the Vertex Correction in an external field is being performed and results obtained so far for special kinematics are consistent with known results.

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

    SciTech Connect

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

    1989-01-01

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

  4. Iron beam acceleration using direct plasma injection scheme

    NASA Astrophysics Data System (ADS)

    Okamura, M.; Kanesue, T.; Yamamoto, T.; Fuwa, Y.

    2014-02-01

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

  5. An Expert System For Tuning Particle-Beam Accelerators

    NASA Astrophysics Data System (ADS)

    Lager, Darrel L.; Brand, Hal R.; Maurer, William J.; Searfus, Robert M.; Hernandez, Jose E.

    1989-03-01

    We have developed a proof-of-concept prototype of an expert system for tuning particle beam accelerators. It is designed to function as an intelligent assistant for an operator. In its present form it implements the strategies and reasoning followed by the operator for steering through the beam transport section of the Advanced Test Accelerator at Lawrence Livermore Laboratory's Site 300. The system is implemented in the language LISP using the Artificial Intelligence concepts of frames, daemons, and a representation we developed called a Monitored Decision Script.

  6. An expert system for tuning particle-beam accelerators

    SciTech Connect

    Lager, D.L.; Brand, H.R.; Maurer, W.J.; Searfus, R.M.; Hernandez, J.E.

    1989-01-12

    We have developed a proof-of-concept prototype of an expert system for tuning particle beam accelerators. It is designed to function as an intelligent assistant for an operator. In its present form it implements the strategies and reasoning followed by the operator for steering through the beam transport section of the Advanced Test Accelerator at Lawrence Livermore Laboratory's Site 300. The system is implemented in the language LISP using the Artificial Intelligence concepts of frames, daemons, and a representation we developed called a Monitored Decision Script. 4 refs., 5 figs.

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

    SciTech Connect

    Lee, S. Y.

    2014-04-07

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

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

    NASA Astrophysics Data System (ADS)

    Lotov, K. V.

    2015-10-01

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

  9. Beam Physics of Integrable Optics Test Accelerator at Fermilab

    SciTech Connect

    Nagaitsev, S.; Valishev, A.; Danilov, V.V.; Shatilov, D.N.; /Novosibirsk, IYF

    2012-05-01

    Fermilab's Integrable Optics Test Accelerator (IOTA) is an electron storage ring designed for testing advanced accelerator physics concepts, including implementation of nonlinear integrable beam optics and experiments on optical stochastic cooling. The machine is currently under construction at the Advanced Superconducting Test Accelerator facility. In this report we present the goals and the current status of the project, and describe the details of machine design. In particular, we concentrate on numerical simulations setting the requirements on the design and supporting the choice of machine parameters.

  10. Ion bunch length effects on the beam-beam interaction in a high luminosity ring-ring electron-ion collider with head-on beam-beam compensation

    SciTech Connect

    Montag, C.; Fischer, W.

    2010-05-23

    The luminosity of a ring-ring electron-ion collider is limited by the beam-beam effect on the electrons. Simulation studies have shown that for short ion bunches this limit can be significantly increased by head-on beam-beam compensation via an electron lens. However, due to the large beam-beam parameter experienced by the electrons, together with an ion bunch length comparable to the beta-function at the IP, electrons perform a sizeable fraction of a betatron oscillation period inside both the long ion bunches and the electron lens. Recent results of our simulation studies of this effect will be presented.

  11. Auto-focusing accelerating hyper-geometric laser beams

    NASA Astrophysics Data System (ADS)

    Kovalev, A. A.; Kotlyar, V. V.; Porfirev, A. P.

    2016-02-01

    We derive a new solution to the paraxial wave equation that defines a two-parameter family of three-dimensional structurally stable vortex annular auto-focusing hyper-geometric (AH) beams, with their complex amplitude expressed via a degenerate hyper-geometric function. The AH beams are found to carry an orbital angular momentum and be auto-focusing, propagating on an accelerating path toward a focus, where the annular intensity pattern is ‘sharply’ reduced in diameter. An explicit expression for the complex amplitude of vortex annular auto-focusing hyper-geometric-Gaussian beams is derived. The experiment has been shown to be in good agreement with theory.

  12. New high-current Dynamitron accelerators for electron beam processing

    NASA Astrophysics Data System (ADS)

    Cleland, M. R.; Thompson, C. C.; Saito, H.; Lisanti, T. F.; Burgess, R. G.; Malone, H. F.; Loby, R. J.; Galloway, R. A.

    1993-06-01

    The material throughput capabilities of RDI's new 550 keV and 800 keV Dynamitron R accelerators have been enhanced by increasing their beam current ratings from 100 mA to 160 mA. Future requirements up to 200 mA have been anticipated in the designs. The high-voltage power supply, beam scanner and beam window have all been modified to accommodate the higher current ratings. A new programmable control system has also been developed. The basic design concepts are described and performance data are presented in this paper.

  13. Heavy ion beam acceleration in the KEK digital accelerator: Induction acceleration from 200 keV to a few tens of MeV

    NASA Astrophysics Data System (ADS)

    Yoshimoto, T.; Barata, M.; Iwashita, T.; Harada, S.; Arakawa, D.; Arai, T.; Liu, X.; Adachi, T.; Asao, H.; Kadokura, E.; Kawakubo, T.; Kubo, T.; Leo, K. W.; Nakanishi, H.; Okada, Y.; Okamura, K.; Okazaki, K.; Someya, H.; Takayama, K.; Wake, M.

    2014-01-01

    The procedure for induction acceleration of a heavy ion beam of A/Q=4 in the KEK digital accelerator is reported. This paper discusses essential issues associated with induction acceleration of ion beams from low energies, including injection error, relatively large closed orbit distortion, and a fully predictive control method for the acceleration.

  14. Beam Head Erosion in Self-Ionized Plasma Wakefield Accelerators

    SciTech Connect

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

    2008-01-28

    In the recent plasma wakefield accelerator experiments at SLAC, the energy of the particles in the tail of the 42 GeV electron beam were doubled in less than one meter [1]. Simulations suggest that the acceleration length was limited by a new phenomenon--beam head erosion in self-ionized plasmas. In vacuum, a particle beam expands transversely in a distance given by {beta}*. In the blowout regime of a plasma wakefield [2], the majority of the beam is focused by the ion channel, while the beam head slowly spreads since it takes a finite time for the ion channel to form. It is observed that in self-ionized plasmas, the head spreading is exacerbated compared to that in pre-ionized plasmas, causing the ionization front to move backward (erode). A simple theoretical model is used to estimate the upper limit of the erosion rate for a bi-gaussian beam by assuming free expansion of the beam head before the ionization front. Comparison with simulations suggests that half this maximum value can serve as an estimate for the erosion rate. Critical parameters to the erosion rate are discussed.

  15. Beam head erosion in self-ionized plasma wakefield accelerators

    NASA Astrophysics Data System (ADS)

    Zhou, Miaomiao; Clayton, Chris; Huang, Chengkun; Joshi, Chan; Lu, Wei; Marsh, Ken; Mori, Warren; Katsouleas, Tom; Muggli, Patric; Oz, Erdem; Berry, Melissa; Blumenfeld, Ian; Decker, Franz-Josef; Hogan, Mark; Ischebeck, Rasmus; Iverson, Richard; Kirby, Neil; Siemman, Robert; Walz, Dieter

    2007-11-01

    In the recent plasma wakefield accelerator experiments at SLAC, the energy of the particles in the tail of the 42 GeV electron beam were doubled in less than one meter [1]. Simulations suggest that the acceleration length was limited by a new phenomenon -- beam head erosion in self-ionized plasmas. In vacuum, a particle beam expands transversely in a distance given by beta*. In the blowout regime of a plasma wakefield [2], the majority of the beam is focused by the ion channel, while the beam head slowly spreads since it takes a finite time for the ion channel to form. Beam/plasma parameter scan in a large range using simulations shows that in self-ionized plasmas, the head spreading is exacerbated compared to that in pre-ionized plasmas, causing the ionization front to move backward (erode). A theoretical analysis on the erosion rate dependence on beam/plasma parameters and its implications on future afterburner relevant experiments will be provided. [1] I. Blumenfeld et al., Nature 445, 741(2007) [2] J. B. Rosenzweig et al., Phys. Rev. A 44, R6189 (1991)

  16. Beam dynamics at the main LEBT of RAON accelerator

    NASA Astrophysics Data System (ADS)

    Jin, Hyunchang; Jang, Ji-Ho

    2015-10-01

    The high-intensity rare isotope accelerator (RAON) of the Rare Isotope Science Project (RISP) in Daejeon, Korea, has been designed to accelerate multiple-charge-state beams. The ion beams, which are generated by using an electron cyclotron resonance ion source (ECR-IS), will be transported through the main low energy beam transport (LEBT) system to the radio frequency quadrupole (RFQ). While passing the beams through the LEBT, we should keep the transverse beam size and longitudinal emittance small. Furthermore, the matching of required twiss parameter at the RFQ entrance will be performed by using electro-static quadrupoles at the main LEBT matching section which is from the multi-harmonic buncher (MHB) to the entrance of the RFQ. We will briefly review the new aspects of the main LEBT lattice, and the beam matching at the main LEBT matching section will be presented. In addition, the effects of various errors on the beam orbit and the correction of a distorted orbit will be discussed.

  17. Collective acceleration of electrons and ions in a high current relativistic electron beam. Final report

    SciTech Connect

    Nation, J.A.

    1992-12-31

    This report describes work carried out on DOE contract number DE-AC02-80ER10569 during the period December 15, 1979 to May 31, 1992. The original purpose of this research was to investigate the use of slow space charge waves on weakly relativistic electron beams for ion acceleration. The work had three major objectives: development of a suitable ion injector, growth and study of the properties of slow space charge waves on an electron beam, and a combination of the two components into a suitable proof-of-principle demonstration of the wave accelerator. Work focused on the first two of these objectives. Control of the space charge waves` phase velocity was not obtained to the degree required for a working accelerator, so the project was duly terminated in favor of a program which focused on generating ultra high power microwave signals suitable for use in the next linear collider. Work done to develop suitable efficient, inexpensive, phase-stable microwave sources, with peak powers of up to 1 GW in the X band in pulses shorter than 1 ns, is described. Included are lists of the journal and conference papers resulting from this work, as well as a list of graduate students who completed their Ph.D. studies on the projects described in this report.

  18. Low energy beam transport for facility for rare isotope beams driver linear particle accelerator

    SciTech Connect

    Sun, L. T.; Leitner, D.; Machicoane, G.; Pozdeyev, E.; Winklehner, D.; Zhao, Q.; Smirnov, V.; Vorozhtsov, S. B.

    2012-02-15

    The driver linac for the facility for rare isotope beams (FRIB) will provide a wide range of primary ion beams for nuclear physics research. The linac will be capable of accelerating a uranium beam to an energy of up to 200 Mev/u and delivering it to a fragmentation target with a maximum power of 400 kW. Stable ion beams will be produced by a high performance electron cyclotron resonance ion source operating at 28 GHz. The ion source will be located on a high voltage platform to reach an initial beam energy of 12 keV/u. After extraction, the ion beam will be transported vertically down to the linac tunnel in a low energy beam transport (LEBT) system and injected into a radio frequency quadrupole (RFQ) operating at a frequency of 80.5 MHz. To meet the beam power requirements, simultaneous acceleration of two-charge states will be used for heavier ions ({>=}Xe). This paper presents the layout of the FRIB LEBT and the beam dynamics in the LEBT. In particular, simulation and design of the beam line section before charge state selection will be detailed. The need to use an achromatic design for the charge state selection system and the advantage of an ion beam collimation system to limit the emittance of the beam injected into the RFQ will be discussed in this paper.

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

    DOEpatents

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

    1995-08-08

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

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

    DOEpatents

    Bogaty, John M. (Lombard, IL); Clifft, Benny E. (Park Forest, IL); Bollinger, Lowell M. (Downers Grove, IL)

    1995-01-01

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

  1. Polarized Proton Acceleration in AGS and RHIC

    SciTech Connect

    Roser, Thomas

    2008-02-06

    As the first hadron accelerator and collider consisting of two independent superconducting rings RHIC has operated with a wide range of beam energies and particle species including polarized proton beams. The acceleration of polarized beams in both the injector and the collider rings is complicated by numerous depolarizing spin resonances. Partial and full Siberian snakes have made it possible to overcome the depolarization and beam polarizations of up to 65% have been reached at 100 GeV in RHIC.

  2. POLARIZED PROTON ACCELERATION IN AGS AND RHIC.

    SciTech Connect

    ROSER,T.

    2007-09-10

    As the first hadron accelerator and collider consisting of two independent superconducting rings RHIC has operated with a wide range of beam energies and particle species including polarized proton beams. The acceleration of polarized beams in both the injector and the collider rings is complicated by numerous depolarizing spin resonances. Partial and full Siberian snakes have made it possible to overcome the depolarization and beam polarizations of up to 65% have been reached at 100 GeV in RHIC.

  3. LATTICES FOR HIGH-POWER PROTON BEAM ACCELERATION AND SECONDARY BEAM COLLECTION AND COOLING.

    SciTech Connect

    WANG, S.; WEI, J.; BROWN, K.; GARDNER, C.; LEE, Y.Y.; LOWENSTEIN, D.; PEGGS, S.; SIMOS, N.

    2006-06-23

    Rapid cycling synchrotrons are used to accelerate high-intensity proton beams to energies of tens of GeV for secondary beam production. After primary beam collision with a target, the secondary beam can be collected, cooled, accelerated or decelerated by ancillary synchrotrons for various applications. In this paper, we first present a lattice for the main synchrotron. This lattice has: (a) flexible momentum compaction to avoid transition and to facilitate RF gymnastics (b) long straight sections for low-loss injection, extraction, and high-efficiency collimation (c) dispersion-free straights to avoid longitudinal-transverse coupling, and (d) momentum cleaning at locations of large dispersion with missing dipoles. Then, we present a lattice for a cooler ring for the secondary beam. The momentum compaction across half of this ring is near zero, while for the other half it is normal. Thus, bad mixing is minimized while good mixing is maintained for stochastic beam cooling.

  4. Luminometer for the future International Linear Collider -Simulation and Beam Test Results

    NASA Astrophysics Data System (ADS)

    Aguilar, J. A.; Pawlik, B.; Kulis, S.; Idzik, M.; Chrzaszcz, M.; Daniluk, W.; Kielar, E.; Kotula, J.; Moszczynski, A.; Oliwa, K.; Wierba, W.; Zawiejski, L.; Afanaciev, K.; Henschel, H.; Ignatenko, A.; Kollowa, S.; Lohmann, W.; Novgorodova, O.; Schuwalow, S.; Levy, I.

    LumiCal will be the luminosity calorimeter for the proposed International Large Detector of the International Linear Collider (ILC). The ILC physics program requires the integrated luminosity to be measured with a relative precision on the order of 10e-3, or 10e-4 when running in GigaZ mode. Luminosity will be determined by counting Bhabha scattering events coincident in the two calorimeter modules placed symmetrically on opposite sides of the interaction point. To meet these goals, the energy resolution of the calorimeter must be better than 1.5% at high energies. LumiCal has been designed as a 30-layer sampling calorimeter with tungsten as the passive material and silicon as the active material. Monte Carlo simulation using the Geant4 software framework has been used to identify design elements which adversely impact energy resolution and correct for them without loss of statistics. BeamCal, covering polar angles smaller than LumiCal, will serve for beam tuning, luminosity optimisation and high energy electron detection. Secondly, prototypes of the sensors and electronics for both detectors have been evaluated during beam tests, the results of which are also presented here.

  5. Reliability of Beam Loss Monitors System for the Large Hadron Collider

    SciTech Connect

    Guaglio, G.; Dehning, B.; Santoni, C.

    2004-11-10

    The employment of superconducting magnets in high energy colliders opens challenging failure scenarios and brings new criticalities for the whole system protection. For the LHC beam loss protection system, the failure rate and the availability requirements have been evaluated using the Safety Integrity Level (SIL) approach. A downtime cost evaluation is used as input for the SIL approach. The most critical systems, which contribute to the final SIL value, are the dump system, the interlock system, the beam loss monitors system and the energy monitor system. The Beam Loss Monitors System (BLMS) is critical for short and intense particle losses, while at medium and higher loss time it is assisted by other systems, such as the quench protection system and the cryogenic system. For BLMS, hardware and software have been evaluated in detail. The reliability input figures have been collected using historical data from the SPS, using temperature and radiation damage experimental data as well as using standard databases. All the data have been processed by reliability software (Isograph). The analysis ranges from the components data to the system configuration.

  6. Spin transport and polarimetry in the beam delivery system of the international linear collider

    NASA Astrophysics Data System (ADS)

    Beckmann, M.; List, J.; Vauth, A.; Vormwald, B.

    2014-07-01

    Polarised electron and positron beams are key ingredients to the physics programme of future linear colliders. Due to the chiral nature of weak interactions in the Standard Model and possibly beyond the knowledge of the luminosity-weighted average beam polarisation at the e+e- interaction point is of similar importance as the knowledge of the luminosity and has to be controlled to permille-level precision in order to fully exploit the physics potential. The current concept to reach this challenging goal combines measurements from Laser-Compton polarimeters before and after the interaction point with measurements at the interaction point. A key element for this enterprise is the understanding of spin-transport effects between the polarimeters and the interaction point as well as collision effects. We show that without collisions, the polarimeters can be cross-calibrated to 0.1 %, and we discuss in detail the impact of collision effects and beam parameters on the polarisation value relevant for the interpretation of the e+e- collision data.

  7. Semiconductor devices as track detectors in high energy colliding beam experiments

    SciTech Connect

    Ludlam, T

    1980-01-01

    In considering the design of experiments for high energy colliding beam facilities one quickly sees the need for better detectors. The full exploitation of machines like ISABELLE will call for detector capabilities beyond what can be expected from refinements of the conventional approaches to particle detection in high energy physics experiments. Over the past year or so there has been a general realization that semiconductor device technology offers the possibility of position sensing detectors having resolution elements with dimensions of the order of 10 microns or smaller. Such a detector could offer enormous advantages in the design of experiments, and the purpose of this paper is to discuss some of the possibilities and some of the problems.

  8. Effect of Field Errors in Muon Collider IR Magnets on Beam Dynamics

    SciTech Connect

    Alexahin, Y.; Gianfelice-Wendt, E.; Kapin, V.V.; /Fermilab

    2012-05-01

    In order to achieve peak luminosity of a Muon Collider (MC) in the 10{sup 35} cm{sup -2}s{sup -1} range very small values of beta-function at the interaction point (IP) are necessary ({beta}* {le} 1 cm) while the distance from IP to the first quadrupole can not be made shorter than {approx}6 m as dictated by the necessity of detector protection from backgrounds. In the result the beta-function at the final focus quadrupoles can reach 100 km making beam dynamics very sensitive to all kind of errors. In the present report we consider the effects on momentum acceptance and dynamic aperture of multipole field errors in the body of IR dipoles as well as of fringe-fields in both dipoles and quadrupoles in the ase of 1.5 TeV (c.o.m.) MC. Analysis shows these effects to be strong but correctable with dedicated multipole correctors.

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

    SciTech Connect

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

    2013-11-15

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

  10. Beam by design: Laser manipulation of electrons in modern accelerators

    NASA Astrophysics Data System (ADS)

    Hemsing, Erik; Stupakov, Gennady; Xiang, Dao; Zholents, Alexander

    2014-07-01

    Accelerator-based light sources such as storage rings and free-electron lasers use relativistic electron beams to produce intense radiation over a wide spectral range for fundamental research in physics, chemistry, materials science, biology, and medicine. More than a dozen such sources operate worldwide, and new sources are being built to deliver radiation that meets with the ever-increasing sophistication and depth of new research. Even so, conventional accelerator techniques often cannot keep pace with new demands and, thus, new approaches continue to emerge. In this article, a variety of recently developed and promising techniques that rely on lasers to manipulate and rearrange the electron distribution in order to tailor the properties of the radiation are reviewed. Basic theories of electron-laser interactions, techniques to create microstructures and nanostructures in electron beams, and techniques to produce radiation with customizable waveforms are reviewed. An overview of laser-based techniques for the generation of fully coherent x rays, mode-locked x-ray pulse trains, light with orbital angular momentum, and attosecond or even zeptosecond long coherent pulses in free-electron lasers is presented. Several methods to generate femtosecond pulses in storage rings are also discussed. Additionally, various schemes designed to enhance the performance of light sources through precision beam preparation including beam conditioning, laser heating, emittance exchange, and various laser-based diagnostics are described. Together these techniques represent a new emerging concept of "beam by design" in modern accelerators, which is the primary focus of this article.

  11. An Accelerated Collaboration Meets with Beaming Success

    SciTech Connect

    Hazi, A U

    2007-02-09

    Maintaining a smaller, aging U.S. nuclear weapons stockpile without underground nuclear testing requires the capability to verify and validate the complex computer calculations on which stockpile confidence is based. This capability, in turn, requires nonnuclear hydrodynamic tests (hydrotests) that can x-ray stages of the implosion process, providing freeze-frame photos of materials imploding at speeds of more than 16,000 kilometers per hour. The images will yield important information on shapes and densities of metals and other materials under the extreme pressures and temperatures generated by the detonation of high explosives. The Dual-Axis Radiographic Hydrodynamics Test (DARHT) Facility at Los Alamos national Laboratory is a two-arm x-ray imaging system that will provide such images, capturing the inner workings of a mock nuclear explosion with high resolution. Scientists compare the radiographic images with computer models, examine the differences, and refine the models to more accurately represent weapon behavior. One of DARHT's arms (now called DARHT-II) recently got a ''leg up'' through a collaboration of Lawrence Livermore and Los Alamos scientists, using a Livermore accelerator to test its subsystems and codes.

  12. PREVENTING POLLUTION USING ISO 14001 AT A PARTICLE ACCELERATOR THE RELATIVISTIC HEAVY ION COLLIDER PROJECT.

    SciTech Connect

    BRIGGS,S.L.K.; MUSOLINO,S.V.

    2001-06-01

    In early 1997 Brookhaven National Laboratory (BNL) discovered that the spent fuel pool of their High Flux Beam Reactor was leaking tritium into the groundwater. Community members, activist groups, politicians and regulators were outraged with the poor environmental management practices at BNL. The reactor was shut down and the Department of Energy (DOE) terminated the contract with the existing Management Company. At this same time, a major new scientific facility, the Relativistic Heavy Ion Collider (RHIC), was nearing the end of construction and readying for commissioning. Although environmental considerations had been incorporated into the design of the facility; some interested parties were skeptical that this new facility would not cause significant environmental impacts. RHIC management recognized that the future of its operation was dependent on preventing pollution and allaying concerns of its stakeholders. Although never done at a DOE National Laboratory before Brookhaven Science Associates, the new management firm, committed to implementing an Environmental Management System (EMS) and RHIC managers volunteered to deploy it within their facility on an extremely aggressive schedule. Several of these IS0 requirements contribute directly to preventing pollution, an area where particular emphasis was placed. This paper describes how Brookhaven used the following key IS0 14001 elements to institutionalize Pollution Prevention concepts: Environmental Policy, Aspects, Objectives and Targets, Environmental Management Program, Structure and Responsibility, Operational Controls, Training, and Management Review. In addition, examples of implementation at the RHIC Project illustrate how BNL's premiere facility was able to demonstrate to interested parties that care had been taken to implement technological and administrative controls to minimize environmental impacts, while at the same time reduce the applicability of regulatory requirements to their operations.

  13. Beam dynamics design for uranium drift tube linear accelerator

    NASA Astrophysics Data System (ADS)

    Dou, Wei-Ping; He, Yuan; Lu, Yuan-Rong

    2014-07-01

    KONUS beam dynamics design of uranium DTL with LORASR code is presented. The 238U34+ beam, whose current is 5.0 emA, is accelerated from injection energy of 0.35 MeV/u to output energy of 1.30 MeV/u by IH-DTL operated at 81.25 MHz in HIAF project at IMP of CAS. It achieves a transmission efficiency of 94.95% with a cavity length of 267.8 cm. The optimization aims are the reduction of emittance growth, beam loss and project costs. Because of the requirements of CW mode operation, the designed average acceleration gradient is about 2.48 MV/m. The maximum axial field is 10.2 MV/m, meanwhile the Kilpatrick breakdown field is 10.56 MV/m at 81.25 MHz.

  14. Acceleration of electrons in strong beam-plasma interactions

    NASA Technical Reports Server (NTRS)

    Wilhelm, K.; Bernstein, W.; Kellogg, P. J.; Whalen, B. A.

    1984-01-01

    The effects of strong beam-plasma interactions on the electron population of the upper atmosphere have been investigated in an electron acceleration experiment performed with a sounding rocket. The rocket carried the Several Complex Experiments (SCEX) payload which included an electron accelerator, three disposable 'throwaway' detectors (TADs), and a stepped electron energy analyzer. The payload was launched in an auroral arc over the rocket at altitudes of 157 and 178 km, respectively. The performance characteristics of the instruments are discussed in detail. The data are combined with the results of laboratory measurements and show that electrons with energies of at least two and probably four times the injection energy of 2 keV were observed during strong beam-plasma interaction events. The interaction events occurred at pitch angles of 54 and 126 degrees. On the basis of the data it is proposed that the superenergization of the electrons is correlated with the length of the beam-plasma interaction region.

  15. ELECTROMAGNETIC SIMULATIONS OF DIELECTRIC WALL ACCELERATOR STRUCTURES FOR ELECTRON BEAM ACCELERATION

    SciTech Connect

    Nelson, S D; Poole, B R

    2005-05-05

    Dielectric Wall Accelerator (DWA) technology incorporates the energy storage mechanism, the switching mechanism, and the acceleration mechanism for electron beams. Electromagnetic simulations of DWA structures includes these effects and also details of the switch configuration and how that switch time affects the electric field pulse which accelerates the particle beam. DWA structures include both bi-linear and bi-spiral configurations with field gradients on the order of 20MV/m and the simulations include the effects of the beampipe, the beampipe walls, the DWA High Gradient Insulator (HGI) insulating stack, wakefield impedance calculations, and test particle trajectories with low emittance gain. Design trade-offs include the transmission line impedance (typically a few ohms), equilibration ring optimization, driving switch inductances, and layer-to-layer coupling effects and the associated affect on the acceleration pulse's peak value.

  16. Reliability of Beam Loss Monitor Systems for the Large Hadron Collider

    SciTech Connect

    Guaglio, G.; Dehning, B.; Santoni, C.

    2005-06-08

    The increase of beam energy and beam intensity, together with the use of super conducting magnets, opens new failure scenarios and brings new criticalities for the whole accelerator protection system. For the LHC beam loss protection system, the failure rate and the availability requirements have been evaluated using the Safety Integrity Level (SIL) approach. A downtime cost evaluation is used as input for the SIL approach. The most critical systems, which contribute to the final SIL value, are the dump system, the interlock system, the beam loss monitors system, and the energy monitor system. The Beam Loss Monitors System (BLMS) is critical for short and intense particles losses at 7 TeV and assisted by the Fast Beam Current Decay Monitors at 450 GeV. At medium and higher loss time it is assisted by other systems, such as the quench protection system and the cryogenic system. For BLMS, hardware and software have been evaluated in detail. The reliability input figures have been collected using historical data from the SPS, using temperature and radiation damage experimental data as well as using standard databases. All the data has been processed by reliability software (Isograph). The analysis spaces from the components data to the system configuration.

  17. Undulator radiation driven by laser-wakefield accelerator electron beams

    NASA Astrophysics Data System (ADS)

    Wiggins, S. M.; Anania, M. P.; Welsh, G. H.; Brunetti, E.; Cipiccia, S.; Grant, P. A.; Reboredo, D.; Manahan, G.; Grant, D. W.; Jaroszynski, D. A.

    2015-05-01

    The Advanced Laser-Plasma High-Energy Accelerators towards X-rays (ALPHA-X) programme is developing laserplasma accelerators for the production of ultra-short electron bunches with subsequent generation of coherent, bright, short-wavelength radiation pulses. The new Scottish Centre for the Application of Plasma-based Accelerators (SCAPA) will develop a wide range of applications utilising such light sources. Electron bunches can be propagated through a magnetic undulator with the aim of generating fully coherent free-electron laser (FEL) radiation in the ultra-violet and Xrays spectral ranges. Demonstration experiments producing spontaneous undulator radiation have been conducted at visible and extreme ultra-violet wavelengths but it is an on-going challenge to generate and maintain electron bunches of sufficient quality in order to stimulate FEL behaviour. In the ALPHA-X beam line experiments, a Ti:sapphire femtosecond laser system with peak power 20 TW has been used to generate electron bunches of energy 80-150 MeV in a 2 mm gas jet laser-plasma wakefield accelerator and these bunches have been transported through a 100 period planar undulator. High peak brilliance, narrow band spontaneous radiation pulses in the vacuum ultra-violet wavelength range have been generated. Analysis is provided with respect to the magnetic quadrupole beam transport system and subsequent effect on beam emittance and duration. Requirements for coherent spontaneous emission and FEL operation are presented.

  18. New Physics of Technology and Full Parallel Data-out Detectors for ?+?- Colliders and Quantum Accelerators

    NASA Astrophysics Data System (ADS)

    Jing, Shen

    1996-11-01

    New conception of collider should emerge when the development of HEP machine lags behind the Livingston line. Thus, ?+?- collider is becoming in DPPD-TEEET-CDDC state space. But to cope with bunch cooling, rejecting the great background, and readout rare and unknown events, R & D is necessary. Hence, new EEE physics and new BI physics; new devices; new analogic discrimination, new digital triggering, new parallel architecture of readout and online computer system have been investigated.

  19. New physics of technology and full parallel data-out detectors for ? +? - colliders and quantum accelerators

    NASA Astrophysics Data System (ADS)

    Shen, Jing

    1996-11-01

    New conception of collider should emerge when the development of HEP machine lags behind the Livingston line. Thus, ? +? - collider is becoming in DPPDTEEETCDDC state space. But to cope with bunch cooling, rejecting the great background, and readout rare and unknown events, R & D is necessary. Hence, new EEE physics and new BI physics; new devices; new analogic discrimination, new digital triggering, new parallel architecture of readout and online computer system have been investigated.

  20. Fusion reactions initiated by laser-accelerated particle beams in a laser-produced plasma.

    PubMed

    Labaune, C; Baccou, C; Depierreux, S; Goyon, C; Loisel, G; Yahia, V; Rafelski, J

    2013-01-01

    The advent of high-intensity-pulsed laser technology enables the generation of extreme states of matter under conditions that are far from thermal equilibrium. This in turn could enable different approaches to generating energy from nuclear fusion. Relaxing the equilibrium requirement could widen the range of isotopes used in fusion fuels permitting cleaner and less hazardous reactions that do not produce high-energy neutrons. Here we propose and implement a means to drive fusion reactions between protons and boron-11 nuclei by colliding a laser-accelerated proton beam with a laser-generated boron plasma. We report proton-boron reaction rates that are orders of magnitude higher than those reported previously. Beyond fusion, our approach demonstrates a new means for exploring low-energy nuclear reactions such as those that occur in astrophysical plasmas and related environments. PMID:24104859

  1. Fusion reactions initiated by laser-accelerated particle beams in a laser-produced plasma

    NASA Astrophysics Data System (ADS)

    Labaune, C.; Baccou, C.; Depierreux, S.; Goyon, C.; Loisel, G.; Yahia, V.; Rafelski, J.

    2013-10-01

    The advent of high-intensity-pulsed laser technology enables the generation of extreme states of matter under conditions that are far from thermal equilibrium. This in turn could enable different approaches to generating energy from nuclear fusion. Relaxing the equilibrium requirement could widen the range of isotopes used in fusion fuels permitting cleaner and less hazardous reactions that do not produce high-energy neutrons. Here we propose and implement a means to drive fusion reactions between protons and boron-11 nuclei by colliding a laser-accelerated proton beam with a laser-generated boron plasma. We report proton-boron reaction rates that are orders of magnitude higher than those reported previously. Beyond fusion, our approach demonstrates a new means for exploring low-energy nuclear reactions such as those that occur in astrophysical plasmas and related environments.

  2. UNDULATOR-BASED LASER WAKEFIELD ACCELERATOR ELECTRON BEAM DIAGNOSTIC

    SciTech Connect

    Bakeman, M.S.; Fawley, W.M.; Leemans, W. P.; Nakamura, K.; Robinson, K.E.; Schroeder, C.B.; Toth, C.

    2009-05-04

    to couple the THUNDER undulator to the LOASIS Lawrence Berkeley National Laboratory (LBNL) laser wakefield accelerator (LWFA). Currently the LWFA has achieved quasi-monoenergetic electron beams with energies up to 1 GeV. These ultra-short, high-peak-current, electron beams are ideal for driving a compact XUV free electron laser (FEL). Understanding the electron beam properties such as the energy spread and emittance is critical for achieving high quality light sources with high brightness. By using an insertion device such as an undulator and observing changes in the spontaneous emission spectrum, the electron beam energy spread and emittance can be measured with high precision. The initial experiments will use spontaneous emission from 1.5 m of undulator. Later experiments will use up to 5 m of undulator with a goal of a high gain, XUV FEL.

  3. A large distributed digital camera system for accelerator beam diagnostics

    NASA Astrophysics Data System (ADS)

    Catani, L.; Cianchi, A.; Di Pirro, G.; Honkavaara, K.

    2005-07-01

    Optical diagnostics, providing images of accelerated particle beams using radiation emitted by particles impinging a radiator, typically a fluorescent screen, has been extensively used, especially on electron linacs, since the 1970's. Higher intensity beams available in the last decade allow extending the use of beam imaging techniques to perform precise measurements of important beam parameters such as emittance, energy, and energy spread using optical transition radiation (OTR). OTR-based diagnostics systems are extensively used on the superconducting TESLA Test Facility (TTF) linac driving the vacuum ultraviolet free electron laser (VUV-FEL) at the Deutsches Elektronen-Synchrotron facility. Up to 30 optical diagnostic stations have been installed at various positions along the 250-m-long linac, each equipped with a high-performance digital camera. This paper describes the new approach to the design of the hardware and software setups required by the complex topology of such a distributed camera system.

  4. High fidelity 3-dimensional models of beam-electron cloud interactions in circular accelerators

    NASA Astrophysics Data System (ADS)

    Feiz Zarrin Ghalam, Ali

    Electron cloud is a low-density electron profile created inside the vacuum chamber of circular machines with positively charged beams. Electron cloud limits the peak current of the beam and degrades the beams' quality through luminosity degradation, emittance growth and head to tail or bunch to bunch instability. The adverse effects of electron cloud on long-term beam dynamics becomes more and more important as the beams go to higher and higher energies. This problem has become a major concern in many future circular machines design like the Large Hadron Collider (LHC) under construction at European Center for Nuclear Research (CERN). Due to the importance of the problem several simulation models have been developed to model long-term beam-electron cloud interaction. These models are based on "single kick approximation" where the electron cloud is assumed to be concentrated at one thin slab around the ring. While this model is efficient in terms of computational costs, it does not reflect the real physical situation as the forces from electron cloud to the beam are non-linear contrary to this model's assumption. To address the existing codes limitation, in this thesis a new model is developed to continuously model the beam-electron cloud interaction. The code is derived from a 3-D parallel Particle-In-Cell (PIC) model (QuickPIC) originally used for plasma wakefield acceleration research. To make the original model fit into circular machines environment, betatron and synchrotron equations of motions have been added to the code, also the effect of chromaticity, lattice structure have been included. QuickPIC is then benchmarked against one of the codes developed based on single kick approximation (HEAD-TAIL) for the transverse spot size of the beam in CERN-LHC. The growth predicted by QuickPIC is less than the one predicted by HEAD-TAIL. The code is then used to investigate the effect of electron cloud image charges on the long-term beam dynamics, particularly on the transverse tune shift of the beam at CERN Super Proton Synchrotron (SPS) ring. The force from the electron cloud image charges on the beam cancels the force due to cloud compression formed on the beam axis and therefore the tune shift is mainly due to the uniform electron cloud density. (Abstract shortened by UMI.)

  5. Quasimonoenergetic electron beams from laser wakefield acceleration in pure nitrogen

    SciTech Connect

    Mo, M. Z.; Ali, A.; Fedosejevs, R.; Fourmaux, S.; Lassonde, P.; Kieffer, J. C.

    2012-02-13

    Quasimonoenergetic electron beams with maximum energy >0.5 GeV and 2 mrad divergence have been generated in pure nitrogen gas via wakefield acceleration with 80 TW, 30 fs laser pulses. Long low energy tail features were typically observed due to continuous ionization injection. The measured peak electron energy decreased with the plasma density, agreeing with the predicted scaling for electrons. The experiments showed a threshold electron density of 3x10{sup 18}cm{sup -3} for self-trapping. Our experiments suggest that pure Nitrogen is a potential candidate gas to achieve GeV monoenergetic electrons using the ionization induced injection scheme for laser wakefield acceleration.

  6. ELIMED, future hadrontherapy applications of laser-accelerated beams

    NASA Astrophysics Data System (ADS)

    Cirrone, Giuseppe A. P.; Carpinelli, Massimo; Cuttone, Giacomo; Gammino, Santo; Bijan Jia, S.; Korn, Georg; Maggiore, Mario; Manti, Lorenzo; Margarone, Daniele; Prokupek, Jan; Renis, Marcella; Romano, Francesco; Schillaci, Francesco; Tomasello, Barbara; Torrisi, Lorenzo; Tramontana, Antonella; Velyhan, Andriy

    2013-12-01

    Laser-ion acceleration has recently gained a great interest as an alternative to conventional and more expensive acceleration techniques. These ion beams have desirable qualities such as small source size, high luminosity and small emittance to be used in different fields as Nuclear Physics, Medical Physics, etc. This is very promising specially for the future perspective of a new concept of hadrontherapy based on laser-based devices could be developed, replacing traditional accelerating machines. Before delivering laser-driven beams for treatments they have to be handled, cleaned from unwanted particles and characterized in order to have the clinical requirements. In fact ion energy spectra have exponential trend, almost 100% energy spread and a wide angular divergence which is the biggest issue in the beam transport and, hence, in a wider use of this technology. In order to demonstrate the clinical applicability of laser-driven beams new collaboration between ELI-Beamlines project researchers from Prague (Cz) and a INFN-LNS group from Catania (I) has been already launched and scientists from different countries have already express their will in joining the project. This cooperation has been named ELIMED (MEDical application at ELIBeamlines) and will take place inside the ELI-Beamlines infrastructure located in Prague. This work describes the schedule of the ELIMED project and the design of the energy selector which will be realized at INFN-LNS. The device is an important part of the whole transport beam line which will be realised in order to make the ion beams suitable for medical applications.

  7. Beam dynamics simulation of the Spallation Neutron Source linear accelerator

    SciTech Connect

    Takeda, H.; Billen, J.H.; Bhatia, T.S.

    1998-12-31

    The accelerating structure for Spallation Neutron Source (SNS) consists of a radio-frequency-quadrupole-linac (RFQ), a drift-tube-linac (DTL), a coupled-cavity-drift-tube-linac (CCDTL), and a coupled-cavity-linac (CCL). The linac is operated at room temperature. The authors discuss the detailed design of linac which accelerates an H{sup {minus}} pulsed beam coming out from RFQ at 2.5 MeV to 1000 MeV. They show a detailed transition from 402.5 MHz DTL with a 4 {beta}{lambda} structure to a CCDTL operated at 805 MHz with a 12 {beta}{lambda} structure. After a discussion of overall feature of the linac, they present an end-to-end particle simulation using the new version of the PARMILA code for a beam starting from the RFQ entrance through the rest of the linac. At 1000 MeV, the beam is transported to a storage ring. The storage ring requires a large ({+-}500-keV) energy spread. This is accomplished by operating the rf-phase in the last section of the linac so the particles are at the unstable fixed point of the separatrix. They present zero-current phase advance, beam size, and beam emittance along the entire linac.

  8. Transformer ratio saturation in a beam-driven wakefield accelerator

    NASA Astrophysics Data System (ADS)

    Farmer, J. P.; Martorelli, R.; Pukhov, A.

    2015-12-01

    We show that for beam-driven wakefield acceleration, the linearly ramped, equally spaced train of bunches typically considered to optimise the transformer ratio only works for flat-top bunches. Through theory and simulation, we explain that this behaviour is due to the unique properties of the plasma response to a flat-top density profile. Calculations of the optimal scaling for a train of Gaussian bunches show diminishing returns with increasing bunch number, tending towards saturation. For a periodic bunch train, a transformer ratio of 23 was achieved for 50 bunches, rising to 40 for a fully optimised beam.

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

    SciTech Connect

    Ludewig, H.; Aronson, A.

    2011-03-01

    The primary advantages that accelerator driven systems have over critical reactors are: (1) Greater flexibility regarding the composition and placement of fissile, fertile, or fission product waste within the blanket surrounding the target, and (2) Potentially enhanced safety brought about by operating at a sufficiently low value of the multiplication factor to preclude reactivity induced events. The control of the power production can be achieved by vary the accelerator beam current. Furthermore, once the beam is shut off the system shuts down. The primary difference between the operation of an accelerator driven system and a critical system is the issue of beam interruptions of the accelerator. These beam interruptions impose thermo-mechanical loads on the fuel and mechanical components not found in critical systems. Studies have been performed to estimate an acceptable number of trips, and the value is significantly less stringent than had been previously estimated. The number of acceptable beam interruptions is a function of the length of the interruption and the mission of the system. Thus, for demonstration type systems and interruption durations of 1sec < t < 5mins, and t > 5mins 2500/yr and 50/yr are deemed acceptable. However, for industrial scale power generation without energy storage type systems and interruption durations of t < 1sec., 1sec < t < 10secs., 10secs < t < 5mins, and t > 5mins, the acceptable number of interruptions are 25000, 2500, 250, and 3 respectively. However, it has also been concluded that further development is required to reduce the number of trips. It is with this in mind that the following study was undertaken. The primary focus of this study will be the merit of a multi-beam target system, which allows for multiple spallation sources within the target/blanket assembly. In this manner it is possible to ameliorate the effects of sudden accelerator beam interruption on the surrounding reactor, since the remaining beams will still be supplying source neutrons. The proton beam will be assumed to have an energy of 1 GeV, and the target material will be natural lead, which will also be the coolant for the reactor assembly. Three proton beam arrangements will be considered, first a single beam (the traditional arrangement) with an entry at the assembly center, two more options will consist of three and six entry locations. The reactor fuel assembly parameters will be based on those of the S-PRISM fast reactor proposed by GE, and the fuel composition and type will be based on that proposed by Aker Solutions for use in their accelerator driven thorium reactor. The following table summarizes the parameters to be used in this study. The isotopic composition of the fertile material is 100% Th-232, and the plutonium isotopic distribution corresponds to that characteristic of the discharge from a typical LWR, following five years of decay. Thus, the isotopic distribution for the plutonium is; Pu-238 2.5%, Pu-239 53.3%, Pu-240 25.1%, Pu-241 11.8%, and Pu-242 7.3%.

  10. Bipolar pulse generator for intense pulsed ion beam accelerator

    SciTech Connect

    Ito, H.; Igawa, K.; Kitamura, I.; Masugata, K.

    2007-01-15

    A new type of pulsed ion beam accelerator named ''bipolar pulse accelerator'' (BPA) has been proposed in order to improve the purity of intense pulsed ion beams. To confirm the principle of the BPA, we developed a bipolar pulse generator for the bipolar pulse experiment, which consists of a Marx generator and a pulse forming line (PFL) with a rail gap switch on its end. In this article, we report the first experimental result of the bipolar pulse and evaluate the electrical characteristics of the bipolar pulse generator. When the bipolar pulse generator was operated at 70% of the full charge condition of the PFL, the bipolar pulse with the first (-138 kV, 72 ns) and the second pulse (+130 kV, 70 ns) was successfully obtained. The evaluation of the electrical characteristics indicates that the developed generator can produce the bipolar pulse with fast rise time and sharp reversing time.

  11. Simulation of the Beam-Ion Instability in the Electron Damping Ring of the International Linear Collider

    SciTech Connect

    Wang, L.; Cai, Y.; Raubenheimer, T.; /SLAC

    2007-07-06

    Ion induced beam instability is one critical issue for the electron damping ring of the International Linear Collider (ILC) due to its ultra small emittance of 2pm. Bunch train filling pattern is proposed to mitigate the instability and bunch-by-bunch feedback is applied to suppress it. Multibunch train fill pattern is introduced in the electron beam to reduce the number of trapped ions. Our study shows that the ion effects can be significantly mitigated by using multiple gaps. However, the beam can still suffer from the beam-ion instability driven by the accumulated ions that cannot escape from the beam during the gaps. The effects of beam fill pattern, emittance, vacuum and various damping mechanism are studied using self-consistent program, which includes the optics of the ring.

  12. Manipulating nonlinear optical processes with accelerating light beams

    SciTech Connect

    Bahabad, Alon; Murnane, Margaret M.; Kapteyn, Henry C.

    2011-09-15

    We show theoretically that accelerating light beams can be used to manipulate nonlinear optical processes through spatiotemporal quasi-phase-matching, allowing for unprecedented temporal and spectral shaping of the generated light. As a proof of principle, we demonstrate exquisite control over the high-order harmonic frequency conversion process, showing efficient enhancement of an extremely broad range of harmonics emitted during a selected quarter-cycle of the driving laser pulse.

  13. Trends for Electron Beam Accelerator Applications in Industry

    NASA Astrophysics Data System (ADS)

    Machi, Sueo

    2011-02-01

    Electron beam (EB) accelerators are major pieces of industrial equipment used for many commercial radiation processing applications. The industrial use of EB accelerators has a history of more than 50 years and is still growing in terms of both its economic scale and new applications. Major applications involve the modification of polymeric materials to create value-added products, such as heat-resistant wires, heat-shrinkable sheets, automobile tires, foamed plastics, battery separators and hydrogel wound dressing. The surface curing of coatings and printing inks is a growing application for low energy electron accelerators, resulting in an environmentally friendly and an energy-saving process. Recently there has been the acceptance of the use of EB accelerators in lieu of the radioactive isotope cobalt-60 as a source for sterilizing disposable medical products. Environmental protection by the use of EB accelerators is a new and important field of application. A commercial plant for the cleaning flue gases from a coal-burning power plant is in operation in Poland, employing high power EB accelerators. In Korea, a commercial plant uses EB to clean waste water from a dye factory.

  14. Far Future Colliders and Required R&D Program

    SciTech Connect

    Shiltsev, V.; /Fermilab

    2012-06-01

    Particle colliders for high energy physics have been in the forefront of scientific discoveries for more than half a century. The accelerator technology of the collider has progressed immensely, while the beam energy, luminosity, facility size and the cost have grown by several orders of magnitude. The method of colliding beams has not fully exhausted its potential but its pace of progress has greatly slowed down. In this paper we very briefly review the R&D toward near future colliders and make an attempt to look beyond the current horizon and outline the changes in the paradigm required for the next breakthroughs.

  15. Observation and Characterization of Coherent Optical Radiation and Microbunching Instability in the SLAC Next Linear Collider Test Accelerator

    SciTech Connect

    Weathersby, S.; Dunning, M.; Hast, C.; Jobe, K.; McCormick, D.; Nelson, J.; Xiang, D.; /SLAC

    2011-06-02

    The NLC Test Accelerator (NLCTA) at SLAC is currently configured for a proof-of-principle echo-enabled harmonic generation (EEHG) experiment using an 120 MeV beam. During commissioning, unexpected coherent optical undulator radiation (CUR) and coherent optical transition radiation (COTR) was observed when beam is accelerated off-crest and compressed after the chicanes. The CUR and COTR is likely due to a microbunching instability where the initial small ripples in cathode drive laser is compressed and amplified. In this paper we present the observation and characterization of the CUR, COTR and microbunching instability at NLCTA.

  16. Beam losses from ultra-peripheral nuclear collisions between Pb ions in the Large Hadron Collider and their alleviation

    SciTech Connect

    Bruce, R.; Bocian, D.; Gilardoni, S.; Jowett, J.M.; /CERN

    2009-08-01

    Electromagnetic interactions between colliding heavy ions at the Large Hadron Collider (LHC) at CERN will give rise to localized beam losses that may quench superconducting magnets, apart from contributing significantly to the luminosity decay. To quantify their impact on the operation of the collider, we have used a three-step simulation approach, which consists of optical tracking, a Monte-Carlo shower simulation and a thermal network model of the heat flow inside a magnet. We present simulation results for the case of {sup 208}Pb{sup 82+} ion operation in the LHC, with focus on the alice interaction region, and show that the expected heat load during nominal {sup 208}Pb{sup 82+} operation is 40% above the quench level. This limits the maximum achievable luminosity. Furthermore, we discuss methods of monitoring the losses and possible ways to alleviate their effect.

  17. On the possibilities of using edge detector algorithms for beam spot diagnostics of accelerator beams

    NASA Astrophysics Data System (ADS)

    Lindblad, Th.; Johansson, F.; Kllberg, A.; Lindsey, C. S.; Rosengrd, U.; Szkely, G.

    1994-12-01

    Diagnostics of accelerator beams using TV cameras to observe the beam spot is quite common. Several software algorithms like those based on the work of Sobel, Roberts, Prewitt, Marr-Hildreth, and Canny are applied to the captured image to yield a binary image. For the present purpose, the Canny algorithm is found to produce by far the best result and the data obtained is suggestive of further implementation in similar fields of research.

  18. Negative hydrogen ion source research and beam parameters for accelerators

    SciTech Connect

    Zolkin, Timofey V.; /Fermilab

    2006-09-01

    H{sup -} beams are useful for multi-turn charge-exchange stripping injection into circular accelerators. Studies on a modified ion source for this purpose are presented. This paper includes some theory about a H{sup -} magnetron discharge, ion-electron emission, emittance and problems linked with emittance measurement and calculations. Investigated parameters of the emittance probe for optimal performance give a screen voltage of 150 V and a probe step of about 5 mil. Normalized 90% emittance obtained for this H{sup -} source is 0.22 {pi} mm-mr, for an extraction voltage of 18 kV at a beam energy of 30 keV and a beam current of 11 mA.

  19. Cryogenic systems for the HEB accelerator of the Superconducting Super Collider

    SciTech Connect

    Abramovich, S.; Yuecel, A.

    1994-07-01

    This report discusses the following topics related to the Superconducting Super Collider: Cryogenic system -- general requirements; cryogenic system components; heat load budgets and refrigeration plant capacities; flow and thermal characteristics; process descriptions; cryogenic control instrumentation and value engineering trade-offs.

  20. High-power electrostatic accelerator FEL program for power beaming

    NASA Astrophysics Data System (ADS)

    Elias, Luis R.; Kimel, Isidoro

    1995-04-01

    We discuss details of a technical plan that will lead to the development of a 1 MW, continuous wave (CW), efficient, near infrared electrostatic-accelerator FEL for power beaming applications. Among the advantages of our technical approach are: (a) true cw or pulsed operation is possible; (b) better than 20% wall-power efficiency can be achieved, (c) existing electrostatic accelerator technology will be employed, and (d) only low levels of unwanted ionizing radiation will be produced. We propose to achieve our final objective in three technical steps. The first step is currently under implementation at the University of Central Florida. The main thrust of the present program is to show 1 kW, CW, far-infrared FEL operation with a 1.7 MV electrostatic accelerator. The goal of the second step is to reach 60 kW FEL power in the middle-infrared region using the TANDAR (Argentinian Tandem) accelerator (V equals +17 MV). For the third step we propose using a combination of two high voltage tandem accelerators (V equals +25, -25 MV) to achieve the final goal of 1 MW, CW operation in the near-infrared region.

  1. Editorial: Focus on Laser- and Beam-Driven Plasma Accelerators

    NASA Astrophysics Data System (ADS)

    Joshi, Chan; Malka, Victor

    2010-04-01

    The ability of short but intense laser pulses to generate high-energy electrons and ions from gaseous and solid targets has been well known since the early days of the laser fusion program. However, during the past decade there has been an explosion of experimental and theoretical activity in this area of laser-matter interaction, driven by the prospect of realizing table-top plasma accelerators for research, medical and industrial uses, and also relatively small and inexpensive plasma accelerators for high-energy physics at the frontier of particle physics. In this focus issue on laser- and beam-driven plasma accelerators, the latest advances in this field are described. Focus on Laser- and Beam-Driven Plasma Accelerators Contents Slow wave plasma structures for direct electron acceleration B D Layer, J P Palastro, A G York, T M Antonsen and H M Milchberg Cold injection for electron wakefield acceleration X Davoine, A Beck, A Lifschitz, V Malka and E Lefebvre Enhanced proton flux in the MeV range by defocused laser irradiation J S Green, D C Carroll, C Brenner, B Dromey, P S Foster, S Kar, Y T Li, K Markey, P McKenna, D Neely, A P L Robinson, M J V Streeter, M Tolley, C-G Wahlström, M H Xu and M Zepf Dose-dependent biological damage of tumour cells by laser-accelerated proton beams S D Kraft, C Richter, K Zeil, M Baumann, E Beyreuther, S Bock, M Bussmann, T E Cowan, Y Dammene, W Enghardt, U Helbig, L Karsch, T Kluge, L Laschinsky, E Lessmann, J Metzkes, D Naumburger, R Sauerbrey, M. Scḧrer, M Sobiella, J Woithe, U Schramm and J Pawelke The optimum plasma density for plasma wakefield excitation in the blowout regime W Lu, W An, M Zhou, C Joshi, C Huang and W B Mori Plasma wakefield acceleration experiments at FACET M J Hogan, T O Raubenheimer, A Seryi, P Muggli, T Katsouleas, C Huang, W Lu, W An, K A Marsh, W B Mori, C E Clayton and C Joshi Electron trapping and acceleration on a downward density ramp: a two-stage approach R M G M Trines, R Bingham, Z Najmudin, S Mangles, L O Silva, R Fonseca and P A Norreys Electro-optic shocks from blowout laser wakefields D F Gordon, A Ting, M H Helle, D Kaganovich and B Hafizi Onset of self-steepening of intense laser pulses in plasmas J Vieira, F Fiúza, L O Silva, M Tzoufras and W B Mori Analysis of laser wakefield dynamics in capillary tubes N E Andreev, K Cassou, F Wojda, G Genoud, M Burza, O Lundh, A Persson, B Cros, V E Fortov and C-G Wahlstrom Characterization of the beam loading effects in a laser plasma accelerator C Rechatin, J Faure, X Davoine, O Lundh, J Lim, A Ben-Ismaïl, F Burgy, A Tafzi, A Lifschitz, E Lefebvre and V Malka Energy gain scaling with plasma length and density in the plasma wakefield accelerator P Muggli, I Blumenfeld, C E Clayton, F J Decker, M J Hogan, C Huang, R Ischebeck, R H Iverson, C Joshi, T Katsouleas, N Kirby, W Lu, K A Marsh, W B Mori, E Oz, R H Siemann, D R Walz and M Zhou Generation of tens of GeV quasi-monoenergetic proton beams from a moving double layer formed by ultraintense lasers at intensity 1021-1023Wcm-2 Lu-Le Yu, Han Xu, Wei-Min Wang, Zheng-Ming Sheng, Bai-Fei Shen, Wei Yu and Jie Zhang Carbon ion acceleration from thin foil targets irradiated by ultrahigh-contrast, ultraintense laser pulses D C Carroll, O Tresca, R Prasad, L Romagnani, P S Foster, P Gallegos, S Ter-Avetisyan, J S Green, M J V Streeter, N Dover, C A J Palmer, C M Brenner, F H Cameron, K E Quinn, J Schreiber, A P L Robinson, T Baeva, M N Quinn, X H Yuan, Z Najmudin, M Zepf, D Neely, M Borghesi and P McKenna Numerical modelling of a 10-cm-long multi-GeV laser wakefield accelerator driven by a self-guided petawatt pulse S Y Kalmykov, S A Yi, A Beck, A F Lifschitz, X Davoine, E Lefebvre, A Pukhov, V Khudik, G Shvets, S A Reed, P Dong, X Wang, D Du, S Bedacht, R Zgadzaj, W Henderson, A Bernstein, G Dyer, M Martinez, E Gaul, T Ditmire and M C Downer Effects of laser prepulses on laser-induced proton generation D Batani, R Jafer, M Veltcheva, R Dezulian, O Lundh, F Lindau, A Persson, K Osvay, C-G Wahlström, D C Carroll, P McKenna, A Flacco and V Malka Proton acceleration by moderately relativistic laser pulses interacting with solid density targets Erik Lefebvre, Laurent Gremillet, Anna Lévy, Rachel Nuter, Patrizio Antici, Michaël Carrié, Tiberio Ceccotti, Mathieu Drouin, Julien Fuchs, Victor Malka and David Neely Holographic visualization of laser wakefields P Dong, S A Reed, S A Yi, S Kalmykov, Z Y Li, G Shvets, N H Matlis, C McGuffey, S S Bulanov, V Chvykov, G Kalintchenko, K Krushelnick, A Maksimchuk, T Matsuoka, A G R Thomas, V Yanovsky and M C Downer The scaling of proton energies in ultrashort pulse laser plasma acceleration K Zeil, S D Kraft, S Bock, M Bussmann, T E Cowan, T Kluge, J Metzkes, T Richter, R Sauerbrey and U Schramm Plasma cavitation in ultraintense laser interactions with underdense helium plasmas P M Nilson, S P D Mangles, L Willingale, M C Kaluza, A G R Thomas, M Tatarakis, R J Clarke, K L Lancaster, S Karsch, J Schreiber, Z Najmudin, A E Dangor and K Krushelnick Radiation pressure acceleration of ultrathin foils Andrea Macchi, Silvia Veghini, Tatyana V Liseykina and Francesco Pegoraro Target normal sheath acceleration: theory, comparison with experiments and future perspectives Matteo Passoni, Luca Bertagna and Alessandro Zani Generation of a highly collimated, mono-energetic electron beam from laser-driven plasma-based acceleration Sanyasi Rao Bobbili, Anand Moorti, Prasad Anant Naik and Parshotam Dass Gupta Controlled electron acceleration in the bubble regime by optimizing plasma density Meng Wen, Baifei Shen, Xiaomei Zhang, Fengchao Wang, Zhangying Jin, Liangliang Ji, Wenpeng Wang, Jiancai Xu and Kazuhisa Nakajima A multidimensional theory for electron trapping by a plasma wake generated in the bubble regime I Kostyukov, E Nerush, A Pukhov and V Seredov Investigation of the role of plasma channels as waveguides for laser-wakefield accelerators T P A Ibbotson, N Bourgeois, T P Rowlands-Rees, L S Caballero, S I Bajlekov, P A Walker, S Kneip, S P D Mangles, S R Nagel, C A J Palmer, N Delerue, G Doucas, D Urner, O Chekhlov, R J Clarke, E Divall, K Ertel, P Foster, S J Hawkes, C J Hooker, B Parry, P P Rajeev, M J V Streeter and S M Hooker Divergence of fast ions generated by interaction of intense ultra-high contrast laser pulses with thin foils A Andreev, T Ceccotti, A Levy, K Platonov and Ph Martin The application of laser-driven proton beams to the radiography of intense laser-hohlraum interactions G Sarri, C A Cecchetti, L Romagnani, C M Brown, D J Hoarty, S James, J Morton, M E Dieckmann, R Jung, O Willi, S V Bulanov, F Pegoraro and M Borghesi Laser-driven particle and photon beams and some applications K W D Ledingham and W Galster Target shape effects on monoenergetic GeV proton acceleration Min Chen, Tong-Pu Yu, Alexander Pukhov and Zheng-Ming Sheng

  2. Ion beam generation and focusing on PBFA (Particle Beam Fusion Accelerator) II

    SciTech Connect

    Stinnett, R.W.; Bailey, J.E.; Bieg, K.W.; Coats, R.S.; Chandler, G.; Derzon, M.S.; Desjarlais, M.P.; Dreike, P.L.; Gerber, R.A.; Johnson, D.J.; Leeper, R.J.; Lockner, T.R.; Maenchen, J.; Mehlhorn, T.A.; Pregenzer, A.L.; Quintenz, J.P.; Renk, T.J.; Rosenthal, S.E.; Ruiz, C.L.; Slutz, S.A.; Stygar, W.A.; Tisone, G.C.; Woodworth, J.R. ); Maron, Y. (Weizmann Inst. of Science, R

    1990-01-01

    During the past year we have succeeded in obtaining a 5 TW/cm{sup 2} proton focus on Sandia National Laboratories' Particle Beam Fusion Accelerator (PBFA) II. This has allowed us to shift our experimental emphasis to the implementation of an improved ion diode geometry for higher voltage operation, full azimuthal beam characterization, and especially lithium ion source experiments. We have made significant progress in each of these areas during the past year, demonstrating 10 MV diode operation, {plus minus}10% azimuthal beam symmetry, and promising initial results from lithium ion source experiments. 8 refs., 6 figs.

  3. RHIC sextant test: Accelerator systems and performance

    SciTech Connect

    Pilat, F.; Trbojevic, D.; Ahrens, L.

    1997-08-01

    One sextant of the RHIC Collider was commissioned in early 1997 with beam. We describe here the performance of the accelerator systems, instrumentation subsystems and application software. We also describe a ramping test without beam that took place after the commissioning with beam. Finally, we analyze the implications of accelerator systems performance and their impact on the planning for RHIC installation and commissioning.

  4. The development of colliders

    SciTech Connect

    Sessler, A.M.

    1993-02-01

    Don Kerst, Gersh Budker, and Bruno Touschek were the individuals, and the motivating force, which brought about the development of colliders, while the laboratories at which it happened were Stanford, MURA, the Cambridge Electron Accelerator, Orsay, Frascati, CERN, and Novosibirsk. These laboratories supported, during many years, this rather speculative activity. Of course, many hundreds of physicists contributed to the development of colliders but the men who started it, set it in the right direction, and forcefully made it happen, were Don, Gersh, and Bruno. Don was instrumental in the development of proton-proton colliders, while Bruno and Gersh spearheaded the development of electron-positron colliders. In this brief review of the history, I will sketch the development of the concepts, the experiments, and the technological developments which made possible the development of colliders. It may look as if the emphasis is on theoretical concepts, but that is really not the case, for in this field -- the physics of beams -- the theory and experiment go hand in hand; theoretical understanding and advances are almost always motivated by the need to explain experimental results or the desire to construct better experimental devices.

  5. Optical Probing of Meter Scale Beam Driven Plasma Wakefield Accelerator

    NASA Astrophysics Data System (ADS)

    Zgadzaj, Rafal; Li, Zhengyan; Downer, M. C.; Gesner, Spencer; Corde, Sebastien; Litos, Mike; Clarke, Christine; Schmeltz, Margaux; Allen, James; Green, Selina; Hogan, Mark; Yakimenko, Vitaly; E224 Team

    2014-10-01

    We report results of optical visualization experiment at the FACET/SLAC user facility. Experiment E224, carried out in parallel to the ongoing e-beam driven wakefield experimental campaign at FACET, has the aim of optically observing both the short term and long term plasma structure produced by the e-beam driver. The SLAC plasma wakefield experiments have demonstrated the highest energy gain to date and continue work on further optimization. Direct visualization of the plasma wake structure would aid in the understanding of the dynamics of the beam plasma interaction and acceleration, and its optimization. It also would serve to benchmark simulations results which have been so far the main window into visualizing the beam plasma interaction. We will describe the optical probing geometry used in this initial run, a variation of a method previously developed in our group, as governed by the unique experimental challenges of the FACET beam driven experiments in their current configuration. We will discuss the current results, the limitations of the current experimental configuration, and the changes planned for future experiments.

  6. New Fusion Concept Using Coaxial Passing Through Each Other Self-focusing Colliding Beams (Invention)

    NASA Astrophysics Data System (ADS)

    Chikvashvili, Ioseb

    2011-10-01

    In proposed Concept it is offered to use two ion beams directed coaxially at the same direction but with different velocities (center-of-mass collision energy should be sufficient for fusion), to direct oppositely the relativistic electron beam for only partial compensation of positive space charge and for allowing the combined beam's pinch capability, to apply the longitudinal electric field for compensation of alignment of velocities of reacting particles and also for compensation of energy losses of electrons via Bremsstrahlung. On base of Concept different types of reactor designs can be realized: Linear and Cyclic designs. In the simplest embodiment the Cyclic Reactor (design) may include: betatron type device (circular store of externally injected particles - induction accelerator), pulse high-current relativistic electron injector, pulse high-current slower ion injector, pulse high-current faster ion injector and reaction products extractor. Using present day technologies and materials (or a reasonable extrapolation of those) it is possible to reach: for induction linear injectors (ions&electrons) - currents of thousands A, repeatability - up to 10Hz, the same for high-current betatrons (FFAG, Stellatron, etc.). And it is possible to build the fusion reactor using the proposed Method just today.

  7. MUON COLLIDERS: THE ULTIMATE NEUTRINO BEAMLINES.

    SciTech Connect

    KING,B.J.

    1999-03-29

    It is shown that muon decays in straight sections of muon collider rings will naturally produce highly collimated neutrino beams that can be several orders of magnitude stronger than the beams at existing accelerators. We discuss possible experimental setups and give a very brief overview of the physics potential from such beamlines. Formulae are given for the neutrino event rates at both short and long baseline neutrino experiments in these beams.

  8. Radiation Safety System for SPIDER Neutral Beam Accelerator

    NASA Astrophysics Data System (ADS)

    Sandri, S.; Coniglio, A.; D'Arienzo, M.; Poggi, C.

    2011-12-01

    SPIDER (Source for Production of Ion of Deuterium Extracted from RF Plasma only) and MITICA (Megavolt ITER Injector Concept Advanced) are the ITER neutral beam injector (NBI) testing facilities of the PRIMA (Padova Research Injector Megavolt Accelerated) Center. Both injectors accelerate negative deuterium ions with a maximum energy of 1 MeV for MITICA and 100 keV for SPIDER with a maximum beam current of 40 A for both experiments. The SPIDER facility is classified in Italy as a particle accelerator. At present, the design of the radiation safety system for the facility has been completed and the relevant reports have been presented to the Italian regulatory authorities. Before SPIDER can operate, approval must be obtained from the Italian Regulatory Authority Board (IRAB) following a detailed licensing process. In the present work, the main project information and criteria for the SPIDER injector source are reported together with the analysis of hypothetical accidental situations and safety issues considerations. Neutron and photon nuclear analysis is presented, along with special shielding solutions designed to meet Italian regulatory dose limits. The contribution of activated corrosion products (ACP) to external exposure of workers has also been assessed. Nuclear analysis indicates that the photon contribution to worker external exposure is negligible, and the neutron dose can be considered by far the main radiation protection issue. Our results confirm that the injector has no important radiological impact on the population living around the facility.

  9. Radiation Safety System for SPIDER Neutral Beam Accelerator

    SciTech Connect

    Sandri, S.; Poggi, C.; Coniglio, A.; D'Arienzo, M.

    2011-12-13

    SPIDER (Source for Production of Ion of Deuterium Extracted from RF Plasma only) and MITICA (Megavolt ITER Injector Concept Advanced) are the ITER neutral beam injector (NBI) testing facilities of the PRIMA (Padova Research Injector Megavolt Accelerated) Center. Both injectors accelerate negative deuterium ions with a maximum energy of 1 MeV for MITICA and 100 keV for SPIDER with a maximum beam current of 40 A for both experiments. The SPIDER facility is classified in Italy as a particle accelerator. At present, the design of the radiation safety system for the facility has been completed and the relevant reports have been presented to the Italian regulatory authorities. Before SPIDER can operate, approval must be obtained from the Italian Regulatory Authority Board (IRAB) following a detailed licensing process. In the present work, the main project information and criteria for the SPIDER injector source are reported together with the analysis of hypothetical accidental situations and safety issues considerations. Neutron and photon nuclear analysis is presented, along with special shielding solutions designed to meet Italian regulatory dose limits. The contribution of activated corrosion products (ACP) to external exposure of workers has also been assessed. Nuclear analysis indicates that the photon contribution to worker external exposure is negligible, and the neutron dose can be considered by far the main radiation protection issue. Our results confirm that the injector has no important radiological impact on the population living around the facility.

  10. Suppressing Electron Cloud in Future Linear Colliders

    SciTech Connect

    Pivi, M; Kirby, R.E.; Raubenheimer, T.O.; Le Pimpec, F.; /PSI, Villigen

    2005-05-27

    Any accelerator circulating positively charged beams can suffer from a build-up of an electron cloud (EC) in the beam pipe. The cloud develops through ionization of residual gases, synchrotron radiation and secondary electron emission and, when severe, can cause instability, emittance blow-up or loss of the circulating beam. The electron cloud is potentially a luminosity limiting effect for both the Large Hadron Collider (LHC) and the International Linear Collider (ILC). For the ILC positron damping ring, the development of the electron cloud must be suppressed. This paper discusses the state-of-the-art of the ongoing SLAC and international R&D program to study potential remedies.

  11. Correcting the beam centroid motion in an induction accelerator and reducing the beam breakup instability

    NASA Astrophysics Data System (ADS)

    Coleman, J. E.; Ekdahl, C. A.; Moir, D. C.; Sullivan, G. W.; Crawford, M. T.

    2014-09-01

    Axial beam centroid and beam breakup (BBU) measurements were conducted on an 80 ns FWHM, intense relativistic electron bunch with an injected energy of 3.8 MV and current of 2.9 kA. The intense relativistic electron bunch is accelerated and transported through a nested solenoid and ferrite induction core lattice consisting of 64 elements, exiting the accelerator with a nominal energy of 19.8 MeV. The principal objective of these experiments is to quantify the coupling of the beam centroid motion to the BBU instability and validate the theory of this coupling for the first time. Time resolved centroid measurements indicate a reduction in the BBU amplitude, ???, of 19% and a reduction in the BBU growth rate (?) of 4% by reducing beam centroid misalignments 50% throughout the accelerator. An investigation into the contribution of the misaligned elements is made. An alignment algorithm is presented in addition to a qualitative comparison of experimental and calculated results which include axial beam centroid oscillations, BBU amplitude, and growth with different dipole steering.

  12. Design and development of pulsed electron beam accelerator 'AMBICA - 600'

    NASA Astrophysics Data System (ADS)

    Verma, Rishi; Deb, Pankaj; Shukla, Rohit; Sharma, Surender; Shyam, Anurag

    2012-11-01

    Short duration, high power pulses with fast rise time and good flat-top are essentially required for driving pulsed electron beam diodes. To attain this objective, a dual resonant Tesla transformer based pulsed power accelerator 'AMBICA-600' has been developed. In this newly developed system, a coaxial water line is charged through single turn Tesla transformer that operates in the dual resonant mode. For making the accelerator compact, in the high power pulse forming line, water has been used as dielectric medium because of its high dielectric constant, high dielectric strength and high energy density. The coaxial waterline can be pulsed charged up to 600kV, has impedance of ~5Ω and generates pulse width of ~60ns. The integrated system is capable of producing intense electron beam of 300keV, 60kA when connected to impedance matched vacuum diode. In this paper, system hardware details and experimental results of gigawatt electron beam generation have been presented.

  13. Electron Beam Charge Diagnostics for Laser Plasma Accelerators

    SciTech Connect

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

    2011-06-27

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

  14. Laser-driven ion acceleration with hollow laser beams

    SciTech Connect

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

    2015-01-15

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

  15. Preservation and control of the proton and deuteron polarizations in the proposed electron-ion collider at Jefferson Lab

    SciTech Connect

    Kondratenko, Anatoliy; Derbenev, Yaroslav S.; Filatov, Yury; Lin, Fanglei; Morozov, Vasiliy; Kondratenko, M. A.; Zhang, Yuhong

    2014-01-01

    We propose a scheme of preserving the proton and deuteron beam polarizations during acceleration and storage in the proposed electron-ion collider at Jefferson Lab. This scheme allows one to provide both the longitudinal and transverse polarization orientations of the proton and deuteron beams at the interaction points of the figure-8 ion collider ring. We discuss questions of matching the polarization direction at all stages of the beam transport including the pre-booster, large booster and ion collider ring.

  16. Seismic studies for Fermilab future collider projects

    SciTech Connect

    Lauh, J.; Shiltsev, V.

    1997-11-01

    Ground motion can cause significant beam emittance growth and orbit oscillations in large hadron colliders due to a vibration of numerous focusing magnets. Larger accelerator ring circumference leads to smaller revolution frequency and, e.g. for the Fermilab Very Large Hadron Collider(VLHC) 50-150 Hz vibrations are of particular interest as they are resonant with the beam betatron frequency. Seismic measurements at an existing large accelerator under operation can help to estimate the vibrations generated by the technical systems in future machines. Comparison of noisy and quiet microseismic conditions might be useful for proper choice of technical solutions for future colliders. This article presents results of wide-band seismic measurements at the Fermilab site, namely, in the tunnel of the Tevatron and on the surface nearby, and in two deep tunnels in the Illinois dolomite which is though to be a possible geological environment of the future accelerators.

  17. Feasibility study of aluminum beam tube for the collider: An option for no-coating and no-liner

    SciTech Connect

    Chou, W.

    1994-07-01

    This report proposes to use a single-layer beam tube made of high strength, high resistivity aluminum alloy (such as 7039-T61 or A7N01) to replace the double-layer copper coated stainless steel tube in the SSC Collider. The main reasons are: (1) a potential saving of about $23 million which is basically the baseline cost of the copper coating and (2) the use of an extruded aluminum tube consisting of a beam chamber and a pumping chamber may solve the vacuum problem without any liner.

  18. Beam Polarization at the ILC: the Physics Impact and the Accelerator Solutions

    SciTech Connect

    Aurand, B.; Bailey, I.; Bartels, C.; Brachmann, A.; Clarke, J.; Hartin, A.; Hauptman, J.; Helebrant, C.; Hesselbach, S.; Kafer, D.; List, J.; Lorenzon, W.; Marchesini, I.; Monig, Klaus; Moffeit, K.C.; Moortgat-Pick, G.; Riemann, S.; Schalicke, A.; Schuler, P.; Starovoitov, P.; Ushakov, A.; /DESY /DESY, Zeuthen /Bonn U. /SLAC

    2011-11-23

    In this contribution accelerator solutions for polarized beams and their impact on physics measurements are discussed. Focus are physics requirements for precision polarimetry near the interaction point and their realization with polarized sources. Based on the ILC baseline programme as described in the Reference Design Report (RDR), recent developments are discussed and evaluated taking into account physics runs at beam energies between 100 GeV and 250 GeV, as well as calibration runs on the Z-pole and options as the 1TeV upgrade and GigaZ. The studies, talks and discussions presented at this conference demonstrated that beam polarization and its measurement are crucial for the physics success of any future linear collider. To achieve the required precision it is absolutely decisive to employ multiple devices for testing and controlling the systematic uncertainties of each polarimeter. The polarimetry methods for the ILC are complementary: with the upstream polarimeter the measurements are performed in a clean environment, they are fast and allow to monitor time-dependent variations of polarization. The polarimeter downstream the IP will measure the disrupted beam resulting in high background and much lower statistics, but it allows access to the depolarization at the IP. Cross checks between the polarimeter results give redundancy and inter-calibration which is essential for high precision measurements. Current plans and issues for polarimeters and also energy spectrometers in the Beam Delivery System of the ILC are summarized in reference [28]. The ILC baseline design allows already from the beginning the operation with polarized electrons and polarized positrons provided the spin rotation and the fast helicity reversal for positrons will be implemented. A reversal of the positron helicity significantly slower than that of electrons is not recommended to not compromise the precision and hence the success of the ILC. Recently to use calibration data at the Z resonance for physics has been discussed. It looks promising but further studies are needed to evaluate and to optimize these measurements. Finally it should be remarked: many studies on different physics processes and scenarios at a future linear collider are done for high luminosities and high energy assuming small and well-known uncertainties. Polarization, especially positron polarization, is often considered as not that important. But in order to interpret data and to reduce ambiguities in the measurements, the polarization of electrons and positrons and their very precise knowledge are essential. The ILC design must offer this from the beginning to be prepared for the physics questions after years of LHC operation.

  19. The program in muon and neutrino physics: Superbeams, cold muon beams, neutrino factory and the muon collider

    SciTech Connect

    R. Raja et al.

    2001-08-08

    The concept of a Muon Collider was first proposed by Budker [10] and by Skrinsky [11] in the 60s and early 70s. However, there was little substance to the concept until the idea of ionization cooling was developed by Skrinsky and Parkhomchuk [12]. The ionization cooling approach was expanded by Neufer [13] and then by Palmer [14], whose work led to the formation of the Neutrino Factory and Muon Collider Collaboration (MC) [3] in 1995. The concept of a neutrino source based on a pion storage ring was originally considered by Koshkarev [18]. However, the intensity of the muons created within the ring from pion decay was too low to provide a useful neutrino source. The Muon Collider concept provided a way to produce a very intense muon source. The physics potential of neutrino beams produced by muon storage rings was investigated by Geer in 1997 at a Fermilab workshop [19, 20] where it became evident that the neutrino beams produced by muon storage rings needed for the muon collider were exciting on their own merit. The neutrino factory concept quickly captured the imagination of the particle physics community, driven in large part by the exciting atmospheric neutrino deficit results from the SuperKamiokande experiment. As a result, the MC realized that a Neutrino Factory could be an important first step toward a Muon Collider and the physics that could be addressed by a Neutrino Factory was interesting in its own right. With this in mind, the MC has shifted its primary emphasis toward the issues relevant to a Neutrino Factory. There is also considerable international activity on Neutrino Factories, with international conferences held at Lyon in 1999, Monterey in 2000 [21], Tsukuba in 2001 [22], and another planned for London in 2002.

  20. ACCELERATION OF POLARIZED BEAMS USING MULTIPLE STRONG PARTIAL SIBERIAN SNAKES.

    SciTech Connect

    ROSER,T.; AHRENS,L.; BAI,M.; COURANT,E.; GLENN,J.W.; GUPTA,R.C.; HUANG,H.; LUCCIO,A.U.; MACKAY,W.W.; TSOUPAS,N.; WILLEN,E.; OKAMURA,M.; TAKANO,J.

    2004-10-10

    Acceleration of polarized protons in the energy range of 5 to 25 GeV is particularly difficult since depolarizing spin resonances are strong enough to cause significant depolarization but full Siberian snakes cause intolerably large orbit excursions. Using a 20-30% partial Siberian snake both imperfection and intrinsic resonances can be overcome. Such a strong partial Siberian snake was designed for the Brookhaven AGS using a dual pitch helical superconducting dipole. Multiple strong partial snakes are also discussed for spin matching at beam injection and extraction.

  1. ACCELERATION OF POLARIZED BEAMS USING MULTIPLE STRONG PARTIAL SIBERIAN SNAKES.

    SciTech Connect

    ROSER,T.AHRENS,L.BAI,M.ET AL.

    2004-07-05

    Acceleration of polarized protons in the energy range of 5 to 25 GeV is particularly difficult since depolarizing spin resonances are strong enough to cause significant depolarization but full Siberian snakes cause intolerably large orbit excursions. Using a 20-30% partial Siberian snake both imperfection and intrinsic resonances can be overcome. Such a strong partial Siberian snake was designed for the Brookhaven AGS using a dual pitch helical superconducting dipole. Multiple strong partial snakes are also discussed for spin matching at beam injection and extraction.

  2. Electron Beam Transport in Advanced Plasma Wave Accelerators

    SciTech Connect

    Williams, Ronald L

    2013-01-31

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

  3. Progress on the relativistic klystron two-beam accelerator prototype

    SciTech Connect

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

    1998-07-05

    The technical challenge for making two-beam accelerators into realizable power sources lies in the creation of the drive beam and in its propagation over long distances through multiple extraction sections. This year we have been constructing a 1.2-kA, l-MeV, electron induction prototype injector as a collaborative effort between LBL and LLNL. The electron source will be a 3.5"-diameter, thermionic, flat-surface cathode with a maximum shroud field stress of approximately 165 kV/cm. Additional design parameters for the injector include a pulse length of over 120-ns flat top (1% energy variation), and a normalized edge emittance of less than 200 {pi}-mm-mr. Planned diagnostics include an isolated cathode with resistive divider for direct measurement of current emission, resistive-wall and magnetic probe current monitors for measuring beam current and centroid position, capacitive probes for measuring A-K gap voltage, an energy spectrometer, and a pepper-pot emittance diagnostic. Details of the injector, beam line, and diagnostics are presented.

  4. Levy-Student distributions for halos in accelerator beams

    SciTech Connect

    Cufaro Petroni, Nicola; De Martino, Salvatore; De Siena, Silvio; Illuminati, Fabrizio

    2005-12-15

    We describe the transverse beam distribution in particle accelerators within the controlled, stochastic dynamical scheme of stochastic mechanics (SM) which produces time reversal invariant diffusion processes. This leads to a linearized theory summarized in a Schroedinger-like (SL) equation. The space charge effects have been introduced in recent papers by coupling this S-L equation with the Maxwell equations. We analyze the space-charge effects to understand how the dynamics produces the actual beam distributions, and in particular we show how the stationary, self-consistent solutions are related to the (external and space-charge) potentials both when we suppose that the external field is harmonic (constant focusing), and when we a priori prescribe the shape of the stationary solution. We then proceed to discuss a few other ideas by introducing generalized Student distributions, namely, non-Gaussian, Levy infinitely divisible (but not stable) distributions. We will discuss this idea from two different standpoints: (a) first by supposing that the stationary distribution of our (Wiener powered) SM model is a Student distribution; (b) by supposing that our model is based on a (non-Gaussian) Levy process whose increments are Student distributed. We show that in the case (a) the longer tails of the power decay of the Student laws and in the case (b) the discontinuities of the Levy-Student process can well account for the rare escape of particles from the beam core, and hence for the formation of a halo in intense beams.

  5. Accelerating Radioactive Ion Beams With REX-ISOLDE

    SciTech Connect

    Ames, F.; Emhofer, S.; Habs, D.; Kester, O.; Reisinger, K.; Sieber, T.; Bollen, G.; Cederkaell, J.; Forstner, O.; Wenander, F.; Huber, G.; Wolf, B.; Schwalm, D.; Hahn, R. von; Bergh, P. van den; Duppen, P. van

    2003-08-26

    The post accelerator REX-ISOLDE is installed at the ISOLDE facility at CERN, where a broad variety of radioactive ions can be addressed. Since the end of 2001 beams at the final energy of 2.2 MeV/u are available. REX-ISOLDE uses a unique system of beam bunching and charge breeding. First a Penning trap accumulates and bunches the ions, which are delivered as a quasi-continuous beam from the ISOLDE target-ion-source, and then an electron beam ion source (EBIS) charge-breeds them to a mass-to-charge ratio below 4.5. This enables a very compact design for the following LINAC, consisting of a 4 rod RFQ, an IH structure and three 7-gap-resonators. The later ones allow a variation of the final energy between 0.8 and 2.2 MeV/u. Although the machine is still in the commissioning phase, first physics experiments have been done with neutron rich Na and Mg isotopes and 9Li. A total efficiency of several percent has already been obtained.

  6. RF pulse compression for future linear colliders

    SciTech Connect

    Wilson, P.B.

    1995-05-01

    Future (nonsuperconducting) linear colliders will require very high values of peak rf power per meter of accelerating structure. The role of rf pulse compression in producing this power is examined within the context of overall rf system design for three future colliders at energies of 1.0--1.5 TeV, 5 TeV and 25 TeV. In order keep the average AC input power and the length of the accelerator within reasonable limits, a collider in the 1.0--1.5 TeV energy range will probably be built at an x-band rf frequency, and will require a peak power on the order of 150--200 MW per meter of accelerating structure. A 5 TeV collider at 34 GHz with a reasonable length (35 km) and AC input power (225 MW) would require about 550 MW per meter of structure. Two-beam accelerators can achieve peak powers of this order by applying dc pulse compression techniques (induction linac modules) to produce the drive beam. Klystron-driven colliders achieve high peak power by a combination of dc pulse compression (modulators) and rf pulse compression, with about the same overall rf system efficiency (30--40%) as a two-beam collider. A high gain (6.8) three-stage binary pulse compression system with high efficiency (80%) is described, which (compared to a SLED-11 system) can be used to reduce the klystron peak power by about a factor of two, or alternately, to cut the number of klystrons in half for a 1.0--1.5 TeV x-band collider. For a 5 TeV klystron-driven collider, a high gain, high efficiency rf pulse compression system is essential.

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

    NASA Astrophysics Data System (ADS)

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

    2013-03-01

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

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

    SciTech Connect

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

    2013-03-15

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

  9. Electron beam dynamics in the DARHT-II linear induction accelerator

    SciTech Connect

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

    2008-01-01

    The DARHT-II linear induction accelerator (LIA) accelerates a 2-kA electron beam to more than 17 MeV. The beam pulse has a greater than 1.5-microsecond flattop region over which the electron kinetic energy is constant to within 1%. The beam dynamics are diagnosed with 21 beam-position monitors located throughout the injector, accelerator, and after the accelerator exit, where we also have beam imaging diagnostics. We discuss the tuning of the injector and accelerator, and present data for the resulting beam dynamics. We discuss the tuning procedures and other methods used to minimize beam motion, which is undesirable for its application as a bremsstrahlung source for multi-pulse radiography of exlosively driven hydrodynamic experiments. We also present beam stability measurements, which we relate to previous stability experiments at lower current and energy.

  10. Impact of high energy high intensity proton beams on targets: Case studies for Super Proton Synchrotron and Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    Tahir, N. A.; Sancho, J. Blanco; Shutov, A.; Schmidt, R.; Piriz, A. R.

    2012-05-01

    The Large Hadron Collider (LHC) is designed to collide two proton beams with unprecedented particle energy of 7 TeV. Each beam comprises 2808 bunches and the separation between two neighboring bunches is 25 ns. The energy stored in each beam is 362 MJ, sufficient to melt 500 kg copper. Safety of operation is very important when working with such powerful beams. An accidental release of even a very small fraction of the beam energy can result in severe damage to the equipment. The machine protection system is essential to handle all types of possible accidental hazards; however, it is important to know about possible consequences of failures. One of the critical failure scenarios is when the entire beam is lost at a single point. In this paper we present detailed numerical simulations of the full impact of one LHC beam on a cylindrical solid carbon target. First, the energy deposition by the protons is calculated with the FLUKA code and this energy deposition is used in the BIG2 code to study the corresponding thermodynamic and the hydrodynamic response of the target that leads to a reduction in the density. The modified density distribution is used in FLUKA to calculate new energy loss distribution and the two codes are thus run iteratively. A suitable iteration step is considered to be the time interval during which the target density along the axis decreases by 15%-20%. Our simulations suggest that the full LHC proton beam penetrates up to 25 m in solid carbon whereas the range of the shower from a single proton in solid carbon is just about 3 m (hydrodynamic tunneling effect). It is planned to perform experiments at the experimental facility HiRadMat (High Radiation Materials) at CERN using the proton beam from the Super Proton Synchrotron (SPS), to compare experimental results with the theoretical predictions. Therefore simulations of the response of a solid copper cylindrical target hit by the SPS beam were performed. The particle energy in the SPS beam is 440 GeV while it has the same bunch structure as the LHC beam, except that it has only up to 288 bunches. Beam focal spot sizes of ?=0.1, 0.2, and 0.5 mm have been considered. The phenomenon of significant hydrodynamic tunneling due to the hydrodynamic effects is also expected for the experiments.

  11. Measurement of acceleration and orbital angular momentum of Airy beam and Airy-vortex beam by astigmatic transformation.

    PubMed

    Singh, Brijesh Kumar; Remez, Roei; Tsur, Yuval; Arie, Ady

    2015-11-15

    Special beams, including the Airy beam and the vortex-embedded Airy beam, draw much attention due to their unique features and promising applications. Therefore, it is necessary to devise a straightforward method for measuring these peculiar features of the beams with ease. Hence we present the astigmatic transformation of Airy and Airy-vortex beam. The "acceleration" coefficient of the Airy beam is directly determined from a single image by fitting the astigmatically transformed beam to an analytic expression. In addition, the orbital angular momentum of optical vortex in Airy-vortex beam is measured directly using a single image. PMID:26565887

  12. On a theory of two-beam mechanisms of charged particle acceleration in electrodynamic structures

    NASA Astrophysics Data System (ADS)

    Ostrovsky, A. O.

    1993-09-01

    This work is devoted to the theoretical studies of two-beam mechanisms of charged particle acceleration in electronic structures. The first section continues the outline of results of theoretical studies commenced in the intermediate report and considers the two-beam scheme of acceleration in the plasma waveguide. According to this scheme the strong current relativistic electron beam (REB) excites the intensive plasma waves accelerating the electrons of the second beam. The driving beam is assumed to be density modulated. The preliminary modulation of the driving REB is shown to enhance substantially the acceleration efficiency of relativistic electrons of the driven beam. The second section deals with the two-beam acceleration in the vacuum corrugated waveguide. According to this scheme the excitation of electromagnetic waves and acceleration of driven beam electrons by them is accomplished under different Cherenkov resonances between the particles of beams and the corrugated waveguide field. The electromagnetic field in the periodic structure is known to be the superposition of spatial harmonics. With the small depth of the periodic nonuniformity, the amplitudes of these harmonics decrease fast with their number increasing. Therefore, if the driving beam is in the Cherenkov resonance with the first spatial harmonic and the driven beam is in resonance with the zero space harmonic then the force accelerating the driven beam would be considerably bigger than the force decelerating the driving beam electrons.

  13. On a theory of two-beam mechanisms of charged particle acceleration in electrodynamic structures

    SciTech Connect

    Ostrovsky, A.O.

    1993-09-01

    This work is devoted to the theoretical studies of two-beam mechanisms of charged particle acceleration in electronic structures. The first section continues the outline of results of theoretical studies commenced in the intermediate report and considers the two-beam scheme of acceleration in the plasma waveguide. According to this scheme the strong current relativistic electron beam (REB) excites the intensive plasma waves accelerating the electrons of the second beam. The driving beam is assumed to be density-modulated. The preliminary modulation of the driving REB is shown to enhance substantially the acceleration efficiency of relativistic electrons of the driven beam. The second section deals with the two-beam acceleration in the vacuum corrugated waveguide. According to this scheme the excitation of electromagnetic waves and acceleration of driven beam electrons by them is accomplished under different Cherenkov resonances between the particles of beams and the corrugated waveguide field. The electromagnetic field in the periodic structure is known to be the superposition of spatial harmonics. With the small depth of the periodic nonuniformity the amplitudes of these harmonics decrease fast with their number increasing. Therefore, if the driving beam is in the Cherenkov resonance with the first spatial harmonic and the driven beam is in resonance with the zero space harmonic then the force accelerating the driven beam would be considerably bigger than the force decelerating the driving beam electrons.

  14. Linear analysis of active-medium two-beam accelerator

    NASA Astrophysics Data System (ADS)

    Voin, Miron; Schchter, Levi

    2015-07-01

    We present detailed development of the linear theory of wakefield amplification by active medium and its possible application to a two-beam accelerator (TBA) is discussed. A relativistic train of triggering microbunches traveling along a vacuum channel in an active medium confined by a cylindrical waveguide excites Cherenkov wake in the medium. The wake is a superposition of azimuthally symmetric transverse magnetic modes propagating along a confining waveguide, with a phase velocity equal to the velocity of the triggering bunches. The structure may be designed in such a way that the frequency of one of the modes is close to active-medium resonant frequency, resulting in amplification of the former and domination of a single mode far behind the trigger bunches. Another electron bunch placed in proper phase with the amplified wakefield may be accelerated by the latter. Importantly, the energy for acceleration is provided by the active medium and not the drive bunch as in a traditional TBA. Based on a simplified model, we analyze extensively the impact of various parameters on the wakefield amplification process.

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

    SciTech Connect

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

    2009-10-19

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

  16. Neutrino Factory and Muon Collider Fellow

    SciTech Connect

    Hanson, Gail G.; Snopak, Pavel; Bao, Yu

    2015-03-20

    Muons are fundamental particles like electrons but much more massive. Muon accelerators can provide physics opportunities similar to those of electron accelerators, but because of the larger mass muons lose less energy to radiation, allowing more compact facilities with lower operating costs. The way muon beams are produced makes them too large to fit into the vacuum chamber of a cost-effective accelerator, and the short muon lifetime means that the beams must be reduced in size rather quickly, without losing too many of the muons. This reduction in size is called "cooling." Ionization cooling is a new technique that can accomplish such cooling. Intense muon beams can then be accelerated and injected into a storage ring, where they can be used to produce neutrino beams through their decays or collided with muons of the opposite charge to produce a muon collider, similar to an electron-positron collider. We report on the research carried out at the University of California, Riverside, towards producing such muon accelerators, as part of the Muon Accelerator Program based at Fermilab. Since this research was carried out in a university environment, we were able to involve both undergraduate and graduate students.

  17. Positron Acceleration by Plasma Wakefields Driven by a Hollow Electron Beam

    NASA Astrophysics Data System (ADS)

    Jain, Neeraj; Antonsen, T. M.; Palastro, J. P.

    2015-11-01

    A scheme for positron plasma wakefield acceleration using hollow or donut-shaped electron driver beams is studied. An annular-shaped, electron-free region forms around the hollow driver beam, creating a favorable region (longitudinal field is accelerating and transverse field is focusing) for positron acceleration. For Facility for Advanced Accelerator Experimental Tests (FACET)-like parameters, the hollow beam driver produces accelerating gradients on the order of 10 GV /m . The accelerating gradient increases linearly with the total charge in the driver beam. Simulations show acceleration of a 23-GeV positron beam to 35.4 GeV with a maximum energy spread of 0.4% and very small emittance over a plasma length of 140 cm is possible.

  18. Positron Acceleration by Plasma Wakefields Driven by a Hollow Electron Beam.

    PubMed

    Jain, Neeraj; Antonsen, T M; Palastro, J P

    2015-11-01

    A scheme for positron plasma wakefield acceleration using hollow or donut-shaped electron driver beams is studied. An annular-shaped, electron-free region forms around the hollow driver beam, creating a favorable region (longitudinal field is accelerating and transverse field is focusing) for positron acceleration. For Facility for Advanced Accelerator Experimental Tests (FACET)-like parameters, the hollow beam driver produces accelerating gradients on the order of 10??GV/m. The accelerating gradient increases linearly with the total charge in the driver beam. Simulations show acceleration of a 23-GeV positron beam to 35.4GeV with a maximum energy spread of 0.4% and very small emittance over a plasma length of 140cm is possible. PMID:26588391

  19. 'Accelerators and Beams,' multimedia computer-based training in accelerator physics

    SciTech Connect

    Silbar, R. R.; Browman, A. A.; Mead, W. C.; Williams, R. A.

    1999-06-10

    We are developing a set of computer-based tutorials on accelerators and charged-particle beams under an SBIR grant from the DOE. These self-paced, interactive tutorials, available for Macintosh and Windows platforms, use multimedia techniques to enhance the user's rate of learning and length of retention of the material. They integrate interactive 'On-Screen Laboratories,' hypertext, line drawings, photographs, two- and three-dimensional animations, video, and sound. They target a broad audience, from undergraduates or technicians to professionals. Presently, three modules have been published (Vectors, Forces, and Motion), a fourth (Dipole Magnets) has been submitted for review, and three more exist in prototype form (Quadrupoles, Matrix Transport, and Properties of Charged-Particle Beams). Participants in the poster session will have the opportunity to try out these modules on a laptop computer.

  20. ``Accelerators and Beams,'' multimedia computer-based training in accelerator physics

    NASA Astrophysics Data System (ADS)

    Silbar, R. R.; Browman, A. A.; Mead, W. C.; Williams, R. A.

    1999-06-01

    We are developing a set of computer-based tutorials on accelerators and charged-particle beams under an SBIR grant from the DOE. These self-paced, interactive tutorials, available for Macintosh and Windows platforms, use multimedia techniques to enhance the user's rate of learning and length of retention of the material. They integrate interactive "On-Screen Laboratories," hypertext, line drawings, photographs, two- and three-dimensional animations, video, and sound. They target a broad audience, from undergraduates or technicians to professionals. Presently, three modules have been published (Vectors, Forces, and Motion), a fourth (Dipole Magnets) has been submitted for review, and three more exist in prototype form (Quadrupoles, Matrix Transport, and Properties of Charged-Particle Beams). Participants in the poster session will have the opportunity to try out these modules on a laptop computer.

  1. Lévy-Student distributions for halos in accelerator beams.

    PubMed

    Cufaro Petroni, Nicola; De Martino, Salvatore; De Siena, Silvio; Illuminati, Fabrizio

    2005-12-01

    We describe the transverse beam distribution in particle accelerators within the controlled, stochastic dynamical scheme of stochastic mechanics (SM) which produces time reversal invariant diffusion processes. This leads to a linearized theory summarized in a Schrödinger-like (SL) equation. The space charge effects have been introduced in recent papers by coupling this S-L equation with the Maxwell equations. We analyze the space-charge effects to understand how the dynamics produces the actual beam distributions, and in particular we show how the stationary, self-consistent solutions are related to the (external and space-charge) potentials both when we suppose that the external field is harmonic (constant focusing), and when we a priori prescribe the shape of the stationary solution. We then proceed to discuss a few other ideas by introducing generalized Student distributions, namely, non-Gaussian, Lévy infinitely divisible (but not stable) distributions. We will discuss this idea from two different standpoints: (a) first by supposing that the stationary distribution of our (Wiener powered) SM model is a Student distribution; (b) by supposing that our model is based on a (non-Gaussian) Lévy process whose increments are Student distributed. We show that in the case (a) the longer tails of the power decay of the Student laws and in the case (b) the discontinuities of the Lévy-Student process can well account for the rare escape of particles from the beam core, and hence for the formation of a halo in intense beams. PMID:16486070

  2. Monte Carlo linear accelerator simulation of megavoltage photon beams: Independent determination of initial beam parameters

    SciTech Connect

    Almberg, Sigrun Saur; Frengen, Jomar; Kylling, Arve; Lindmo, Tore

    2012-01-15

    Purpose: To individually benchmark the incident electron parameters in a Monte Carlo model of an Elekta linear accelerator operating at 6 and 15 MV. The main objective is to establish a simplified but still precise benchmarking procedure that allows accurate dose calculations of advanced treatment techniques. Methods: The EGSnrc Monte Carlo user codes BEAMnrc and DOSXYZnrc are used for photon beam simulations and dose calculations, respectively. A 5 x 5 cm{sup 2} field is used to determine both the incident electron energy and the electron radial intensity. First, the electron energy is adjusted to match the calculated depth dose to the measured one. Second, the electron radial intensity is adjusted to make the calculated dose profile in the penumbrae region match the penumbrae measured by GafChromic EBT film. Finally, the mean angular spread of the incident electron beam is determined by matching calculated and measured cross-field profiles of large fields. The beam parameters are verified for various field sizes and shapes. Results: The penumbrae measurements revealed a non-circular electron radial intensity distribution for the 6 MV beam, while a circular electron radial intensity distribution could best describe the 15 MV beam. These electron radial intensity distributions, given as the standard deviation of a Gaussian distribution, were found to be 0.25 mm (in-plane) and 1.0 mm (cross-plane) for the 6 MV beam and 0.5 mm (both in-plane and cross-plane) for the 15 MV beam. Introducing a small mean angular spread of the incident electron beam has a considerable impact on the lateral dose profiles of large fields. The mean angular spread was found to be 0.7 deg. and 0.5 deg. for the 6 and 15 MV beams, respectively. Conclusions: The incident electron beam parameters in a Monte Carlo model of a linear accelerator could be precisely and independently determined by the benchmarking procedure proposed. As the dose distribution in the penumbra region is insensitive to moderate changes in electron energy and angular spread, accurate penumbra measurements is feasible for benchmarking the electron radial intensity distribution. This parameter is particularly important for accurate dosimetry of mlc-shaped fields and small fields.

  3. Design Considerations for Plasma Accelerators Driven by Lasers or Particle Beams

    SciTech Connect

    Schroeder, C. B.; Esarey, E.; Benedetti, C.; Toth, Cs.; Geddes, C. G. R.; Leemans, W. P.

    2010-11-04

    Plasma accelerators may be driven by the ponderomotive force of an intense laser or the space-charge force of a charged particle beam. The implications for accelerator design and the different physical mechanisms of laser-driven and beam-driven plasma acceleration are discussed. Driver propagation is examined, as well as the effects of the excited plasma wave phase velocity. The driver coupling to subsequent plasma accelerator stages for high-energy physics applications is addressed.

  4. Design Considerations for Plasma Accelerators Driven by Lasers or Particle Beams

    SciTech Connect

    Schroeder, C. B.; Esarey, E.; Benedetti, C.; Toth, Cs.; Geddes, C. G. R.; Leemans, W.P.

    2010-06-01

    Plasma accelerators may be driven by the ponderomotive force of an intense laser or the space-charge force of a charged particle beam. The implications for accelerator design and the different physical mechanisms of laser-driven and beam-driven plasma acceleration are discussed. Driver propagation is examined, as well as the effects of the excited plasma wave phase velocity. The driver coupling to subsequent plasma accelerator stages for high-energy physics applications is addressed.

  5. Alignment tolerance of accelerating structures and corrections for future linear colliders

    SciTech Connect

    Kubo, K.; Adolphsen, C.; Bane, K.L.F.; Raubenheimer, T.O.; Thompson, K.A.

    1995-06-01

    The alignment tolerance of accelerating structures is estimated by tracking simulations. Both single-bunch and multi-bunch effects are taken into account. Correction schemes for controlling the single and multi-bunch emittance growth in the case of large misalignment are also tested by simulations.

  6. Neutrino factory and beta beam: accelerator options for future neutrino experiments

    SciTech Connect

    Zisman, Michael S.

    2012-06-03

    Two accelerator options for producing intense neutrino beams a Neutrino Factory based on stored muon beams and a Beta Beam facility based on stored beams of beta unstable ions are described. Technical challenges for each are described and current R&D efforts aimed at mitigating these challenges are indicated. Progress is being made in the design of both types of facility, each of which would extend the state-of-the-art in accelerator science.

  7. METHOD OF PRODUCING AND ACCELERATING AN ION BEAM

    NASA Technical Reports Server (NTRS)

    Foster, John E. (Inventor)

    2005-01-01

    A method of producing and accelerating an ion beam comprising the steps of providing a magnetic field with a cusp that opens in an outward direction along a centerline that passes through a vertex of the cusp: providing an ionizing gas that sprays outward through at least one capillary-like orifice in a plenum that is positioned such that the orifice is on the centerline in the cusp, outward of the vortex of the cusp; providing a cathode electron source, and positioning it outward of the orifice and off of the centerline; and positively charging the plenum relative to the cathode electron source such that the plenum functions as m anode. A hot filament may be used as the cathode electron source, and permanent magnets may be used to provide the magnetic field.

  8. Design of a synchrotron radiation detector for the test beam lines at the Superconducting Super Collider Laboratory

    SciTech Connect

    Hutton, R.D.

    1994-01-01

    As part of the particle- and momentum-tagging instrumentation required for the test beam lines of the Superconducting Super Collider (SSC), the synchrotron radiation detector (SRD) was designed to provide electron tagging at momentum above 75 GeV. In a parallel effort to the three test beam lines at the SSC, schedule demands required testing and calibration operations to be initiated at Fermilab. Synchrotron radiation detectors also were to be installed in the NM and MW beam lines at Femilab before the test beam lines at the SSC would become operational. The SRD is the last instrument in a series of three used in the SSC test beam fines. It follows a 20-m drift section of beam tube downstream of the last silicon strip detector. A bending dipole just in of the last silicon strip detector produces the synchrotron radiation that is detected in a 50-mm-square cross section NaI crystal. A secondary scintillator made of Bicron BC-400 plastic is used to discriminate whether it is synchrotron radiation or a stray particle that causes the triggering of the NaI crystal`s photo multiplier tube (PMT).

  9. Research in accelerator physics (theory)

    NASA Astrophysics Data System (ADS)

    Ohnuma, Shoroku

    1991-01-01

    This report discusses the following topics: beam-beam interaction in colliders with momentum oscillation; isolated difference resonance and evolution of the particle distribution; study of magnet sorting for the SSC High Energy Booster; development of a discrete HESQ; beam dynamics in compact synchrotrons; theoretical problems in multi-stage FEL for two-beam acceleration; operation of Tevatron near integer tunes; and detailed examination of coupling impedance of various devices in storage rings; impact on beams from the insertion devices.

  10. Muon Collider Task Force Report

    SciTech Connect

    Ankenbrandt, C.; Alexahin, Y.; Balbekov, V.; Barzi, E.; Bhat, C.; Broemmelsiek, D.; Bross, A.; Burov, A.; Drozhdin, A.; Finley, D.; Geer, S.; /Fermilab /Argonne /Brookhaven /Jefferson Lab /LBL, Berkeley /MUONS Inc., Batavia /UCLA /UC, Riverside /Mississippi U.

    2007-12-01

    Muon Colliders offer a possible long term path to lepton-lepton collisions at center-of-mass energies {radical}s {ge} 1 TeV. In October 2006 the Muon Collider Task Force (MCTF) proposed a program of advanced accelerator R&D aimed at developing the Muon Collider concept. The proposed R&D program was motivated by progress on Muon Collider design in general, and in particular, by new ideas that have emerged on muon cooling channel design. The scope of the proposed MCTF R&D program includes muon collider design studies, helical cooling channel design and simulation, high temperature superconducting solenoid studies, an experimental program using beams to test cooling channel RF cavities and a 6D cooling demonstration channel. The first year of MCTF activities are summarized in this report together with a brief description of the anticipated FY08 R&D activities. In its first year the MCTF has made progress on (1) Muon Collider ring studies, (2) 6D cooling channel design and simulation studies with an emphasis on the HCC scheme, (3) beam preparations for the first HPRF cavity beam test, (4) preparations for an HCC four-coil test, (5) further development of the MANX experiment ideas and studies of the muon beam possibilities at Fermilab, (6) studies of how to integrate RF into an HCC in preparation for a component development program, and (7) HTS conductor and magnet studies to prepare for an evaluation of the prospects for of an HTS high-field solenoid build for a muon cooling channel.

  11. Education in a rapidly advancing technology: Accelerators and beams

    NASA Astrophysics Data System (ADS)

    Month, Mel

    2000-06-01

    The field of accelerators and beams (A&B) is one of today's fast changing technologies. Because university faculties have not been able to keep pace with the associated advancing knowledge, universities have not been able to play their traditional role of educating the scientists and engineers needed to sustain this technology for use in science, industry, commerce, and defense. This problem for A&B is described and addressed. The solution proposed, a type of "distance" education, is the U.S. Particle Accelerator School (USPAS) created in the early 1980s. USPAS provides the universities with a means of serving the education needs of the institutions using A&B, primarily but not exclusively the national laboratories. The field of A&B is briefly summarized. The need for education outside the university framework, the raison d'être for USPAS, the USPAS method, program structure, and curriculum, and particular USPAS-university connections are explained. The management of USPAS is analyzed, including its unique administrative structure, its institutional ties, and its operations, finance, marketing, and governmental relations. USPAS performance over the years is documented and a business assessment is made. Finally, there is a brief discussion of the future potential for this type of educational program, including possible extrapolation to new areas and/or different environments, in particular, its extra-government potential and its international possibilities.

  12. Fluence and dose measurements for an accelerator neutron beam

    NASA Astrophysics Data System (ADS)

    Liu, Z.; Byun, S. H.; McNeill, F. E.; Mothersill, C. E.; Seymour, C. B.; Prestwich, W. V.

    2007-10-01

    The 3 MV Van de Graaff accelerator at McMaster University accelerator laboratory is extended to a neutron irradiation facility for low-dose bystander effects research. A long counter and an Anderson-Braun type neutron monitor have been used as monitors for the determination of the total fluence. Activation foils were used to determine the thermal neutron fluence rate (around 106 neutrons s-1). Meanwhile, the interactions of neutrons with the monitors have been simulated using a Monte Carlo N Particle (MCNP) code. Bystander effects, i.e. damage occurring in cells that were not traversed by radiation but were in the same radiation environment, have been well observed following both alpha and gamma irradiation of many cell lines. Since neutron radiation involves mixed field (including gamma and neutron radiations), we need to differentiate the doses for the bystander effects from the two radiations. A tissue equivalent proportional counter (TEPC) filled with propane based tissue equivalent gas simulating a 2 ?m diameter tissue sphere has been investigated to estimate the neutron and gamma absorbed doses. A photon dose contamination of the neutron beam is less than 3%. The axial dose distribution follows the inverse square law and lateral and vertical dose distributions are relatively uniform over the irradiation area required by the biological study.

  13. Scintillator diagnostics for the detection of laser accelerated ion beams

    NASA Astrophysics Data System (ADS)

    Cook, N.; Tresca, O.; Lefferts, R.

    2014-09-01

    Laser plasma interaction with ultraintense pulses present exciting schemes for accelerating ions. One of the advantages conferred by using a gaseous laser and target is the potential for a fast (several Hz) repetition rate. This requires diagnostics which are not only suited for a single shot configuration, but also for repeated use. We consider several scintillators as candidates for an imaging diagnostic for protons accelerated to MeV energies by a CO2 laser focused on a gas jet target. We have measured the response of chromium-doped alumina (chromox) and polyvinyl toluene (PVT) screens to protons in the 2-8 MeV range. We have calibrated the luminescent yield in terms of photons emitted per incident proton for each scintillator. We also discuss how light scattering and material properties affect detector resolution. Furthermore, we consider material damage and the presence of an afterglow under intense exposures. Our analysis reveals a near order of magnitude greater yield from chromox in response to proton beams at > 8 MeV energies, while scattering effects favor PVT-based scintillators at lower energies.

  14. Ion Beam Transport Simulations for the 1.7 MV Tandem Accelerator at the Michigan Ion Beam Laboratory

    NASA Astrophysics Data System (ADS)

    Naab, F. U.; Toader, O. F.; Was, G. S.

    The Michigan Ion Beam Laboratory houses a 1.7 MV tandem accelerator. For many years this accelerator was configured to run with three ion sources: a TORoidal Volume Ion Source (TORVIS), a Duoplasmatron source and a Sputter source. In this article we describe an application we have created using the SIMION® code to simulate the trajectories of ion beams produced with these sources through the accelerator. The goal of this work is to have an analytical tool to understand the effect of each electromagnetic component on the ion trajectories. This effect is shown in detailed drawings. Each ion trajectory simulation starts at the aperture of the ion source and ends at the position of the target. Using these simulations, new accelerator operators or users quickly understand how the accelerator system works. Furthermore, these simulations allow analysis of modifications in the ion beam optics of the accelerator by adding, removing or replacing components or changing their relative positions.

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

    SciTech Connect

    Ekdahl, Carl

    2015-11-17

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

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

    SciTech Connect

    Ekdahl, Carl August Jr.

    2015-06-22

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

  17. Ultrashort Electron Beam Pulses and Diagnosis by Advanced Linear Accelerators

    SciTech Connect

    Uesaka, M.; Muroya, Y.; Watanabe, T.; Hosokai, T.; Iijima, H.

    2003-08-26

    240fs 18 MeV low emittance(6 pai mm.mrad) electron beam was generated and its pulse shape was diagnosed by the S-band laser photocathode RF gun and linac. The maximum charge per bunch was 7 nC. This electron pulse was synchronized with 100fs 0.3TW Ti:Sapphire laser with the timing jitter of 330fs(rms). Recently, the Cu cathode(QE10 and -4) was replaced by Mg cathode(QE10 and -3). This system is utilized for radiation chemistry analysis for supercritical water. We have adopted the four diagnostic methods(femtosecond streak camera, coherent transition radiation interferometer, far-infrared polychromator, fluctuation method) and checked their time-resolution precisely. Further, we are doing the experiment on laser plasma cathode by 12TW 50fs laser and He gas jet. Laser plasma wakefield acceleration and electron injection via wavebreaking are planned. We have developed a new theory of self-injection scheme to generate {approx}10fs electron pulse. We have already succeeded in observing 40 MeV low emittance electron beam of 14 nC.

  18. Ultrashort Electron Beam Pulses and Diagnosis by Advanced Linear Accelerators

    NASA Astrophysics Data System (ADS)

    Uesaka, M.; Iijima, H.; Muroya, Y.; Watanabe, T.; Hosokai, T.

    2003-08-01

    240fs 18 MeV low emittance(6 pai mm.mrad) electron beam was generated and its pulse shape was diagnosed by the S-band laser photocathode RF gun and linac. The maximum charge per bunch was 7 nC. This electron pulse was synchronized with 100fs 0.3TW Ti:Sapphire laser with the timing jitter of 330fs(rms). Recently, the Cu cathode(QE10?-4) was replaced by Mg cathode(QE10?-3). This system is utilized for radiation chemistry analysis for supercritical water. We have adopted the four diagnostic methods(femtosecond streak camera, coherent transition radiation interferometer, far-infrared polychromator, fluctuation method) and checked their time-resolution precisely. Further, we are doing the experiment on laser plasma cathode by 12TW 50fs laser and He gas jet. Laser plasma wakefield acceleration and electron injection via wavebreaking are planned. We have developed a new theory of self-injection scheme to generate 10fs electron pulse. We have already succeeded in observing 40 MeV low emittance electron beam of 14 nC.

  19. Beam-breakup calculations for the DARHT accelerator

    SciTech Connect

    Allison, P.; Burns, M.J. ); Caporaso, G.J.; Cole, A.G. )

    1991-01-01

    We have modeled an induction linac that will accelerate a 4-MeV, 3-kA beam of electrons to 16- to 20-MeV in 64 gaps. To suppress beam- breakup (BBU) instabilities induced by excitation of rf deflecting modes, the growth factor {Gamma} must be kept sufficiently small (e.g. < 3). On prototype DARHT cavities, rf measurements have shown that the normally degenerate TM modes are split in frequency by the asymmetry that the two pulsed-power drive rods present to the cavity. If half the cavities had vertical and half had horizontal drive-rod orientations, the effective number of gaps would be reduced by half if there were no coupling between the modes by the solenoidal focusing and if the split modes had no overlap. The LLNL code BREAKUP was used to study BBU growth for drive rod alternation patterns of blocks of 1, 2, 4, 8, 16, 24, 32, or 64 (no alternation) for both constant and alternating polarity solenoids. For alternating polarities the optimum alternation pattern is 2 or 4, whereas for constant polarities BBU is approximately independent of pattern. 9 refs., 5 figs. 2 tabs.

  20. Decontamination of Ametryne HDPE packaging using electron beam accelerator

    NASA Astrophysics Data System (ADS)

    Duarte, C. L.; Andrade, D. C.; Melo, R. P.; Nagatomi, H. R.; Mori, M. N.

    2009-07-01

    This paper is part of a project to evaluate pesticide degradation on commercial polymeric (high-density polyethylene, HDPE) packaging material. The herbicide studied was Ametryne whose residues may be detectable in water, soil and on the surfaces for months or years, depending on the pesticide formulation and type of application. In order to evaluate the efficiency of radiation processing on removal of the pesticides contamination; the packaging material were irradiated using Radiation Dynamics Electron Beam Accelerator with 1,5 MeV energy and 37 kW, in batch system. The samples were irradiated with water, in various absorbed doses. Ametryne was analyzed by gas chromatography after extraction with hexane/dichloromethane (1:1 v/v) solution. The radiation processing yield was evaluated by the destruction G-value (Gd), and the electron beam irradiation processing, showed higher efficiency in destroying Ametryne in the HDPE packaging when the samples were irradiated in the presence of small quantities of water.

  1. The Photon Collider

    NASA Astrophysics Data System (ADS)

    Gronberg, Jeffrey

    The idea of converting an electron linear collider into a photon-photon collider through the addition of high power lasers was put forward in the early 1980s. Progress in the field of high average power, short pulse lasers has brought the state of the art within striking range of what would be required to realize a photon collider. In parallel, the necessary modifications to the detector and accelerator to enable a photon collider have been laid out. The basic concept of the photon collider, the requirements for the laser, and the detector and accelerator impact are reviewed in this article.

  2. Observations and open questions in beam-beam interactions

    SciTech Connect

    Sen, Tanaji; /Fermilab

    2010-08-01

    The first of the hadron colliders, ISR, started operation in 1970. In the following years, the hadron colliders to follow were the SPS (started 1980), the Tevatron (started 1987 first as a fixed target machine), RHIC (started 2000) and most recently the LHC, which started in 2008. HERA was a hybrid that collided electrons and protons. All of these accelerators had or have their performance limited by the effects of the beam-beam interactions. That has also been true for the electron-positron colliders such as LEP, CESR, KEKB and PEPII. In this article I will discuss how the beam-beam limitations arose in some of these machines. The discussion will be focused on common themes that span the different colliders. I will mostly discuss the hadron colliders but sometimes discuss the lepton colliders where relevant. Only a handful of common accelerator physics topics are chosen here, the list is not meant to be exhaustive. A comparative review of beam-beam performance in the ISR, SPS and Tevatron (ca 1989) can be found in reference. Table 1 shows the relevant parameters of colliders (excluding the LHC), which have accelerated protons.

  3. Muon muon collider: Feasibility study

    SciTech Connect

    1996-06-18

    A feasibility study is presented of a 2 + 2 TeV muon collider with a luminosity of L = 10{sup 35} cm{sup {minus}2} s{sup {minus}1}. The resulting design is not optimized for performance, and certainly not for cost; however, it does suffice--the authors believe--to allow them to make a credible case, that a muon collider is a serious possibility for particle physics and, therefore, worthy of R and D support so that the reality of, and interest in, a muon collider can be better assayed. The goal of this support would be to completely assess the physics potential and to evaluate the cost and development of the necessary technology. The muon collider complex consists of components which first produce copious pions, then capture the pions and the resulting muons from their decay; this is followed by an ionization cooling channel to reduce the longitudinal and transverse emittance of the muon beam. The next stage is to accelerate the muons and, finally, inject them into a collider ring which has a small beta function at the colliding point. This is the first attempt at a point design and it will require further study and optimization. Experimental work will be needed to verify the validity of diverse crucial elements in the design.

  4. External-Beam Accelerated Partial Breast Irradiation Using Multiple Proton Beam Configurations

    SciTech Connect

    Wang Xiaochun; Amos, Richard A.; Zhang Xiaodong; Taddei, Phillip J.; Woodward, Wendy A.; Hoffman, Karen E.; Yu, Tse Kuan; Tereffe, Welela; Oh, Julia; Perkins, George H.; Salehpour, Mohammad; Zhang, Sean X.; Sun, Tzou Liang; Gillin, Michael; Buchholz, Thomas A.; Strom, Eric A.

    2011-08-01

    Purpose: To explore multiple proton beam configurations for optimizing dosimetry and minimizing uncertainties for accelerated partial breast irradiation (APBI) and to compare the dosimetry of proton with that of photon radiotherapy for treatment of the same clinical volumes. Methods and Materials: Proton treatment plans were created for 11 sequential patients treated with three-dimensional radiotherapy (3DCRT) photon APBI using passive scattering proton beams (PSPB) and were compared with clinically treated 3DCRT photon plans. Monte Carlo calculations were used to verify the accuracy of the proton dose calculation from the treatment planning system. The impact of range, motion, and setup uncertainty was evaluated with tangential vs. en face beams. Results: Compared with 3DCRT photons, the absolute reduction of the mean of V100 (the volume receiving 100% of prescription dose), V90, V75, V50, and V20 for normal breast using protons are 3.4%, 8.6%, 11.8%, 17.9%, and 23.6%, respectively. For breast skin, with the similar V90 as 3DCRT photons, the proton plan significantly reduced V75, V50, V30, and V10. The proton plan also significantly reduced the dose to the lung and heart. Dose distributions from Monte Carlo simulations demonstrated minimal deviation from the treatment planning system. The tangential beam configuration showed significantly less dose fluctuation in the chest wall region but was more vulnerable to respiratory motion than that for the en face beams. Worst-case analysis demonstrated the robustness of designed proton beams with range and patient setup uncertainties. Conclusions: APBI using multiple proton beams spares significantly more normal tissue, including nontarget breast and breast skin, than 3DCRT using photons. It is robust, considering the range and patient setup uncertainties.

  5. Muon Collider

    SciTech Connect

    Palmer, R.

    2009-10-19

    Parameters are given of muon colliders with center of mass energies of 1.5 and 3 TeV. Pion production is from protons on a mercury target. Capture, decay, and phase rotation yields bunch trains of both muon signs. Six dimensional cooling reduces the emittances until the trains are merged into single bunches, one of each sign. Further cooling in 6 dimensions is then applied, followed by final transverse cooling in 50 T solenoids. After acceleration the muons enter the collider ring. Ongoing R&D is discussed.

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

    DOEpatents

    Maschke, Alfred W. (East Moriches, NY)

    1983-07-05

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

  7. Development of Bipolar Pulse Accelerator for Pulsed Ion Beam Implantation to Semiconductor

    NASA Astrophysics Data System (ADS)

    Masugata, Katsumi; Kawahara, Yoshihiro; Mitsui, Chihiro; Kitamura, Iwao; Takahashi, Takakazu; Tanaka, Yasunori; Tanoue, Hisao; Arai, Kazuo

    2002-12-01

    To improve the purity of the ion beams new type of pulsed power ion accelerator named "bipolar pulse accelerator" was proposed. The accelerator consists of two acceleration gaps (an ion source gap and a post acceleration gap) and a drift tube, and a bipolar pulse is applied to the drift tube to accelerate the beam. In the accelerator intended ions are selectively accelerated and the purity of the ion beam is enhanced. As the first step of the development of the accelerator, a Br-type magnetically insulated acceleration gap is developed. The gap has an ion source of coaxial gas puff plasma gun on the grounded anode and a negative pulse is applied to the cathode to accelerate the ion beam. By using the plasma gun, ion source plasma (nitrogen) of current density around 100 A/cm2 is obtained. In the paper, the experimental results of the evaluation of the ion beam and the characteristics of the gap are shown with the principle and the design concept of the proposed accelerator.

  8. Transverse emittance-preserving arc compressor for high-brightness electron beam-based light sources and colliders

    NASA Astrophysics Data System (ADS)

    Di Mitri, S.; Cornacchia, M.

    2015-03-01

    Bunch length magnetic compression is used in high-brightness linacs driving free-electron lasers (FELs) and particle colliders to increase the peak current of the injected beam. To date, it is performed in dedicated insertions made of few degrees bending magnets and the compression factor is limited by the degradation of the beam transverse emittance owing to emission of coherent synchrotron radiation (CSR). We reformulate the known concept of CSR-driven optics balance for the general case of varying bunch length and demonstrate, through analytical and numerical results, that a 500 pC charge beam can be time-compressed in a periodic 180 deg arc at 2.4 GeV beam energy and lower, by a factor of up to 45, reaching peak currents of up to 2 kA and with a normalized emittance growth at the 0.1 μ \\text{m} rad level. The proposed solution offers new schemes of beam longitudinal gymnastics; an application to an energy recovery linac driving FEL is discussed.

  9. Lattice design and beam dynamics studies of the high energy beam transport line in the RAON heavy ion accelerator

    NASA Astrophysics Data System (ADS)

    Jin, Hyunchang; Jang, Ji-Ho; Jang, Hyojae; Jeon, Dong-O.

    2015-12-01

    In RAON heavy ion accelerator, beams generated by superconducting electron cyclotron resonance ion source (ECR-IS) or Isotope Separation On-Line (ISOL) system are accelerated by lower energy superconducting linac and high energy superconducting linac. The accelerated beams are used in the high energy experimental hall which includes bio-medical and muon-SR facilities, after passing through the high energy beam transport lines. At the targets of those two facilities, the stable and small beams meeting the requirements rigorously are required in the transverse plane. Therefore the beams must be safely sent to the targets and simultaneously satisfy the two requirements, the achromatic condition and the mid-plane symmetric condition, of the targets. For this reason, the lattice design of the high energy beam transport lines in which the long deflecting sections are included is considered as a significant issue in the RAON accelerator. In this paper, we will describe the calculated beam optics satisfying the conditions and present the result of particle tracking simulations with the designed lattice of the high energy beam transport lines in the RAON accelerator. Also, the orbit distortion caused by the machine imperfections and the orbit correction with correctors will be discussed.

  10. The Next Linear Collider Test Accelerator's RF Pulse Compression And Transmission

    SciTech Connect

    Tantawi, S.G.; Adelphson, C.; Holmes, S.; Lavine, Theodore L.; Loewen, R.J.; Nantista, C.; Pearson, C.; Pope, R.; Rifkin, J.; Ruth, R.D.; Vlieks, A.E.; /SLAC

    2011-09-14

    The overmoded rf transmission and pulsed power compression system for SLAC's Next Linear Collider (NLC) program requires a high degree of transmission efficiency and mode purity to be economically feasible. To this end, a number of new, high power components and systems have been developed at X-band, which transmit rf power in the low loss, circular TE01 mode with negligible mode conversion. In addition, a highly efficient SLED-II* pulse compressor has been developed and successfully tested at high power. The system produced a 200 MW, 250 ns wide pulse with a near-perfect flat-top. In this paper we describe the design and test results of the high power pulse compression system using SLED-II. The NLC rf systems use low loss highly over-moded circular waveguides operating in the TE01 mode. The efficiency of the systems is sensitive to the mode purity of the mode excited inside these guides. We used the so called flower petal mode transducer [2] to excite the TE01 mode. This type of mode transducer is efficient, compact and capable of handling high levels of power. To make more efficient systems, we modified this device by adding several mode selective chokes to act as mode purifiers. To manipulate the rf signals we used these modified mode converters to convert back and forth between over-moded circular waveguides and single-moded WR90 rectangular waveguides. Then, we used the relatively simple rectangular waveguide components to do the actual manipulation of rf signals. For example, two mode transducers and a mitered rectangular waveguide bend comprise a 90 degree bend. Also, a magic tee and four mode transducers would comprise a four-port-hybrid, etc. We will discuss the efficiency of an rf transport system based on the above methodology. We also used this methodology in building the SLEDII pulse compression system. At SLAC we built 4 of these pulse systems. In this paper we describe the SLEDII system and compare the performance of these 4 systems at SLAC. We report the experimental procedures used to measure their performance as well as the results of high power tests.

  11. Observation of Electron Cloud Stabilized 1 MeV Beam-Beam d+d Reactons in Self-Colliding Orbits and Feasibility of Electric Isotope Breeder

    NASA Astrophysics Data System (ADS)

    Maglich, Bogdan; Druey, Christian; Iyengar, P. K.; Srinivasan, Mahadeva

    2012-03-01

    D-D Self-Collider ^1,2 is only system in which beam-beam nuclear reactions demonstrated MeV energies. 1.45 MeV DC beam of D2^+ was injected into center of a weak-focusing magnetic field (Ni Ti) B=3.12 Tesla, and dissociated into 2 d^+ stored in Self-Colliding Orbits^3. Energy confinement time T = 23 s (vacuum limited p=10-9 torr), stabilized by driven electron oscillations^4. A simulation^5 shows that 1 DD neutron is produced at an energy cost of 5.36 MeV/n i.e. 140 MWh/g= 8,360/g vs. 160,000/g from beam - target. Simultaneously produced He^3 and T are not only free, but bring 45 fold gain. 5 d's of 0.75 MeV generate 1He^3 +1T +1p+ 1n at cost 5.36 MeV. Hence, it will produce 2 He^3 nuclei (1 He-3, 1 T) plus energy gain of 161 MeV. This will be reduced by the energy gain thus reducing cost to 4.5 from 5.6 MeV. Assumed ion density 5x10 ^14 was achieved in plasmas. Beam injection 100 mA. 1. PRL 54, 796 (1985) NIM A 271 p,.1-167; 2. AIP CP 311, 292 (93); 3. PRL 70, 1818 (93); 4.Part. Acc.1, (70); 5. ``50 Years with Fission'' Symp.Nat. Ac Sci., p. 761 (89)

  12. Energy Amplification and Beam Bunching in a Pulse Line Ion Accelerator

    SciTech Connect

    Roy, P K; Waldron, W L; Yu, S S; Coleman, J E; Henestroza, E; Grote, D P; Baca, D; Bieniosek, F M; Briggs, R J; Davidson, R C; Eylon, S; Friedman, A; Greenway, W G; Leitner, M; Logan, G B; Reginato, L L; Seidl, P A

    2006-06-08

    In a first beam dynamics validation experiment for a new Pulse Line Ion Acceleration (PLIA) concept, the predicted energy amplification and beam bunching were experimentally observed. Beam energy modulation of -80 keV to +150 keV was measured using a PLIA input voltage waveform of -21 kV to +12 kV. Ion pulses accelerated by 150 keV, and bunching by a factor of four were simultaneously achieved. The measured longitudinal phase space and current waveform of the accelerated beam are in good agreement with 3-D particle-in-cell simulations.

  13. Low emittance electron beam generation from a laser wakefield accelerator using two laser pulses with different wavelengths

    NASA Astrophysics Data System (ADS)

    Xu, X. L.; Wu, Y. P.; Zhang, C. J.; Li, F.; Wan, Y.; Hua, J. F.; Pai, C.-H.; Lu, W.; Yu, P.; Joshi, C.; Mori, W. B.

    2014-06-01

    Ionization injection triggered by short wavelength laser pulses inside a nonlinear wakefield driven by a longer wavelength laser is examined via multidimensional particle-in-cell simulations. We find that very bright electron beams can be generated through this two-color scheme in either collinear propagating or transverse colliding geometry. For a fixed laser intensity I, lasers with longer/shorter wavelength ? have larger/smaller ponderomotive potential (?I ?2). The two-color scheme utilizes this property to separate the injection process from the wakefield excitation process. Very strong wakes can be generated at relatively low laser intensities by using a longer wavelength laser driver (e.g., a 10 ?m CO2 laser) due to its very large ponderomotive potential. On the other hand, a short wavelength laser can produce electrons with very small residual momenta (p ? a0?I ?) inside the wake, leading to electron beams with very small normalized emittances (tens of nm). Using particle-in-cell simulations we show that a 10 fs electron beam with 4 pC of charge and a normalized emittance of 50 nm can be generated by combining a 10 ?m driving laser with a 400 nm injection laser, which is an improvement of more than 1 order of magnitude compared to the typical results obtained when a single wavelength laser is used for both the wake formation and ionization injection. With the transverse colliding geometry, simulations show that similarly low emittance and much lower slice energy spread (30 keV, comparing with the typical value of few MeV in the longitudinal injection scheme) can be simultaneously obtained for electron beams with a few pC charge. Such low slice energy spread may have significant advantages in applications relevant to future coherent light sources driven by plasma accelerators.

  14. Reverse Emittance Exchange for Muon Colliders

    SciTech Connect

    V. Ivanov, A. Afanasev, C.M. Ankenbrandt, R.P. Johnson, G.M. Wang, S.A. Bogacz, Y.S. Derbenev

    2009-05-01

    Muon collider luminosity depends on the number of muons in the storage ring and on the transverse size of the beams in collision. Ionization cooling as it is currently envisioned will not cool the beam sizes sufficiently well to provide adequate luminosity without large muon intensities. Six-dimensional cooling schemes will reduce the longitudinal emittance of a muon beam so that smaller high frequency RF cavities can be used for later stages of cooling and for acceleration. However, the bunch length at collision energy is then shorter than needed to match the interaction region beta function. New ideas to shrink transverse beam dimensions by lengthening each bunch will help achieve high luminosity in muon colliders. Analytic expressions for the reverse emittance exchange mechanism were derived, including a new resonant method of beam focusing.

  15. A theory of two-beam acceleration of charged particles in a plasma waveguide

    SciTech Connect

    Ostrovsky, A.O.

    1993-11-01

    The progress made in recent years in the field of high-current relativistic electron beam (REB) generation has aroused a considerable interest in studying REB potentialities for charged particle acceleration with a high acceleration rate T = 100MeV/m. It was proposed, in particular, to employ high-current REB in two-beam acceleration schemes (TBA). In these schemes high current REB (driving beam) excites intense electromagnetic waves in the electrodynamic structure which, in their turn, accelerate particles of the other beam (driven beam). The TBA schemes can be divided into two groups. The first group includes the schemes, where the two beams (driving and driven) propagate in different electrodynamic structures coupled with each other through the waveguides which ensure the microwave power transmission to accelerate driven beam particles. The second group includes the TBA schemes, where the driving and driven beams propagate in one electrodynamic structure. The main aim of this work is to demonstrate by theory the possibility of realizing effectively the TBA scheme in the plasma waveguide. The physical model of the TBA scheme under study is formulated. A set of equations describing the excitation of RF fields by a high-current REB and the acceleration of driven beam electrons is also derived. Results are presented on the the linear theory of plasma wave amplification by the driving beam. The range of system parameters, at which the plasma-beam instability develops, is defined. Results of numerical simulation of the TBA scheme under study are also presented. The same section gives the description of the dynamics of accelerated particle bunching in the high-current REB-excited field. Estimates are given for the accelerating field intensities in the plasma and electron acceleration rates.

  16. Phase dependence of electron acceleration in a tightly focused laser beam

    SciTech Connect

    He Xinkui; Li, R.X.; Shuai, B.; Ge, X.C.; Xu, Z.Z.

    2005-07-15

    Electron acceleration using a tightly focused ultraintensity laser beam is investigated numerically and strong phase dependence is found. The acceleration is periodic to the variety of the initial laser field phase, and the accelerated electrons are emitted in pulses of which the full width is the half period of the laser field. When a 10 PW intense laser beam is used, the electron with energy less than 1 Mev can be accelerated up to energies about 1.4 GeV. The optimal initial condition for electron acceleration is found.

  17. A monolithic relativistic electron beam source based on a dielectric laser accelerator structure

    SciTech Connect

    McNeur, Josh; Carranza, Nestor; Travish, Gil; Yin Hairong; Yoder, Rodney

    2012-12-21

    Work towards a monolithic device capable of producing relativistic particle beams within a cubic-centimeter is detailed. We will discuss the Micro-Accelerator Platform (MAP), an optical laser powered dielectric accelerator as the main building block of this chip-scale source along with a field enhanced emitter and a region for sub-relativistic acceleration.

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

    SciTech Connect

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

    2013-09-15

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

  19. Proceedings of the international workshop on next-generation linear colliders

    SciTech Connect

    Riordan, M.

    1988-12-01

    This report contains papers on the next-generation of linear colliders. The particular areas of discussion are: parameters; beam dynamics and wakefields; damping rings and sources; rf power sources; accelerator structures; instrumentation; final focus; and review of beam-beam interaction.

  20. The CERN SPS proton-antiproton collider

    NASA Astrophysics Data System (ADS)

    Schmidt, Rudiger

    One of CERN's most ambitious and successful projects was the search for the intermediate bosons, W and Z [1]. The accelerator part of the project relied on a number of innovations in accelerator physics and technology. The invention of the method of stochastic cooling and the extension by many orders of magnitude beyond the initial proof of principle demonstration allowed the construction of the Antiproton Accumulator. Major modifications to the 26 GeV PS complex and the conversion of the 300 GeV SPS, which had just started up as an accelerator, to a pbar p collider were required. The SPS collider had to master the beam-beam effect far beyond limits reached before and had to function in a tight symbiosis with the UA1 and UA2 experiments.

  1. Crab Cavities for Linear Colliders

    SciTech Connect

    Burt, G.; Ambattu, P.; Carter, R.; Dexter, A.; Tahir, I.; Beard, C.; Dykes, M.; Goudket, P.; Kalinin, A.; Ma, L.; McIntosh, P.; Shulte, D.; Jones, Roger M.; Bellantoni, L.; Chase, B.; Church, M.; Khabouline, T.; Latina, A.; Adolphsen, C.; Li, Z.; Seryi, Andrei; /SLAC

    2011-11-08

    Crab cavities have been proposed for a wide number of accelerators and interest in crab cavities has recently increased after the successful operation of a pair of crab cavities in KEK-B. In particular crab cavities are required for both the ILC and CLIC linear colliders for bunch alignment. Consideration of bunch structure and size constraints favour a 3.9 GHz superconducting, multi-cell cavity as the solution for ILC, whilst bunch structure and beam-loading considerations suggest an X-band copper travelling wave structure for CLIC. These two cavity solutions are very different in design but share complex design issues. Phase stabilisation, beam loading, wakefields and mode damping are fundamental issues for these crab cavities. Requirements and potential design solutions will be discussed for both colliders.

  2. New acceleration schemes and technologies

    SciTech Connect

    Palmer, R.B.

    1991-02-01

    The search for new acceleration schemes and technologies has in general, been restricted to a search for higher gradient acceleration, and it has been motivated by the aim of reducing the length, and presumably the cost, of new high energy facilities. In particular, it has been argued that very high energy linear colliders will only be practical if much higher acceleration gradients are employed. This report investigates possible higher acceleration gradient and beam luminosity problems.

  3. A new beam loss detector for low-energy proton and heavy-ion accelerators

    NASA Astrophysics Data System (ADS)

    Liu, Zhengzheng; Crisp, Jenna; Russo, Tom; Webber, Robert; Zhang, Yan

    2014-12-01

    The Facility for Rare Isotope Beams (FRIB) to be constructed at Michigan State University shall deliver a continuous, 400 kW heavy ion beam to the isotope production target. This beam is capable of inflicting serious damage on accelerator components, e.g. superconducting RF accelerating cavities. A Beam Loss Monitoring (BLM) System is essential for detecting beam loss with sufficient sensitivity and promptness to inform the machine protection system (MPS) and operations personnel of impending dangerous losses. Radiation transport simulations reveal shortcomings in the use of ionization chambers for the detection of beam losses in low-energy, heavy-ion accelerators. Radiation cross-talk effects due to the folded geometry of the FRIB LINAC pose further complications to locating specific points of beam loss. We propose a newly developed device, named the Loss Monitor Ring (LMR1

  4. Accelerate helical cone-beam CT with graphics hardware

    NASA Astrophysics Data System (ADS)

    Bi, Wenyuan; Chen, Zhiqiang; Zhang, Li; Xing, Yuxiang

    2008-03-01

    Helical cone-beam CT is widely used nowadays because of its rapid scan speed and efficient utilization of x-ray dose. HCT-FDK is an effective reconstruction algorithm on Helical CT. However, like other 3D reconstruction algorithms, HCT-FDK is time consuming because of its large amount of data processing including the convolution and 3D-3D back projection. Recently, GPU is widely used to parallel many reconstruction algorithms. The latest GPU has some nice features, such as large memory, lots of processors, fast 3D texture mapping, and flexible frame buffer object. All these features help reconstruction a lot. In this paper, we present a solution to this problem with GPU. First, we bring a lookup table into HCT-FDK. Then, both convolution and back projection are implemented on GPU. At last, the reconstruction result is directly smoothed and visualized by GPU. Experimental results are given to compare among CPU and two generations of GPU: Geforce 6800GT and Geforce 8800GTX. The comparison was applied both on simulation data and real data. We show that, GPU-accelerated HCT-FDK gets result with similar levels of noise and clarity but gains a speed increase of about 10-100 times faster than using CPU only. With its newer feature, Geforce 8800GTX can get a similar quality like Geforce 6800GT and about 20 times faster.

  5. Improvement of voltage holding and high current beam acceleration by MeV accelerator for ITER NB

    SciTech Connect

    Taniguchi, M.; Kashiwagi, M.; Inoue, T.; Umeda, N.; Watanabe, K.; Tobari, H.; Dairaku, M.; Yamanaka, H.; Tsuchida, K.; Kojima, A.; Hanada, M.; Sakamoto, K.

    2011-09-26

    Voltage holding of -1 MV is an essential issue in development of a multi-aperture multi-grid (MAMuG) negative ion accelerator, of which target is to accelerate 200 A/m{sup 2} H{sup -} ion beam up to the energy of 1 MeV for several tens seconds. Review of voltage holding results ever obtained with various geometries of the accelerators showed that the voltage holding capability was about a half of designed value based on the experiment obtained from ideal small electrode. This is considered due to local electric field concentration in the accelerators, such as edge and steps between multi-aperture grids and its support structures. Based on the detailed investigation with electric field analysis, accelerator was modified to reduce the electric field concentration by reshaping the support structures and expanding the gap length between the grid supports. After the modifications, the accelerator succeeded in sustaining -1 MV for more than one hour in vacuum. Improvement of the voltage holding characteristics progressed the energy and current accelerated by the MeV accelerator. Up to 2010, beam parameters achieved by the MAMuG accelerator were increased to 879 keV, 0.36 A (157 A/m{sup 2}) at perveance matched condition and 937 keV, 0.33 A (144 A/m{sup 2}) slightly under perveance.

  6. Initial operation of the Tevatron collider

    SciTech Connect

    Johnson, R.

    1987-03-01

    The Tevatron is now the highest energy proton synchrotron and the only accelerator made with superconducting magnets. Operating since 1983 as a fixed-target machine at energies up to 800 GeV, it has now been modified to operate as a 900 GeV antiproton-proton collider. This paper describes the initial operation of the machine in this mode. The new features of the Fermilab complex, including the antiproton source and the Main Ring injector with its two overpasses and new rf requirements, are discussed. Beam characteristics in the Tevatron (including lifetimes, emittances, luminosity, beam-beam tune shifts, backgrounds, and low beta complications), the coordination of the steps in the accelerator chain, and the commissioning history are also discussed. Finally, some plans for the improvement of the collider are presented.

  7. Start-to-end simulations for beam dynamics in the RISP heavy-ion accelerator

    NASA Astrophysics Data System (ADS)

    Kim, Eun-San; Bahng, JungBae; Hwang, Ji-Gwang; Choi, Bong-Hyuk; Kim, Hye-Jin; Jeon, Dong-O.

    2015-09-01

    RAON has been designed as a rare isotope accelerator facility for the Rare Isotope Science Project (RISP). The main accelerator for the in-flight system accelerates uranium and proton beams to 200 MeV/u and 660 MeV, respectively, with a beam power of 400 kW. The front-end system consists of two 28 GHz electron cyclotron resonance ion sources (10 keV/u), a low-energy beam transport (LEBT) line with two 90 bends, a multi-harmonic buncher with three different rf frequencies, a radio-frequency quadrupole (RFQ), and a medium-energy beam transport line (MEBT) with three rebunchers and eight quadrupoles. A driver linac system consisting of Linac-1 and Linac-2 has been designed to optimize the beam and accelerator parameters so as to meet the required design goals. A charge stripper section is located between Linac-1 and Linac-2. To optimize these designs, we performed start-to-end simulations with the beams from the LEBT to Linac-2 using 1 million macroparticles. We present the resulting beam dynamics to evaluate the performance of the accelerator. Our simulation results predict that the transmission rate of the uranium beam is 85.8% from the LEBT to Linac-2. The designed facility is expected to achieve the required beam loss condition of less than 1 W/m. The RAON driver linac lattice design was developed and an overview of the beam dynamics is presented.

  8. Simulation of Hollow Electron Beam Collimation in the Fermilab Tevatron Collider

    SciTech Connect

    Morozov, I.A.; Stancari, G.; Valishev, A.; Shatilov, D.N.; /Novosibirsk, IYF

    2012-05-01

    The concept of augmenting the conventional collimation system of high-energy storage rings with a hollow electron beam was successfully demonstrated in experiments at the Tevatron. A reliable numerical model is required for understanding particle dynamics in the presence of a hollow beam collimator. Several models were developed to describe imperfections of the electron beam profile and alignment. The features of the imperfections are estimated from electron beam profile measurements. Numerical simulations of halo removal rates are compared with experimental data taken at the Tevatron.

  9. Conceptual design of the Relativistic Heavy Ion Collider: RHIC

    SciTech Connect

    Samios, Nicholas P.

    1986-05-01

    The complete Relativistic Heavy Ion Collider (RHIC) facility will be a complex set of accelerators and beam transfer equipment connecting them. A significant portion of the total facility either exists or is under construction. Two existing Tandem Van de Graaff accelerators will serve for the initial ion acceleration. Ions with a charge of -1 would be accelerated from ground to +15 MV potential, pass through a stripping foil, and accelerate back to ground potential, where they would pass through a second stripping foil. From there the ions will traverse a long transfer line to the AGS tunnel and be injected into the Booster accelerator. The Booster accelerates the ion bunch, and then the ions pass through one more stripper and then enter the Alternating Gradient Synchrotron (AGS), where they are accelerated to the top AGS energy and transferred to the collider. Bending and focusing of ion beams is to be achieved by superconducting magnets. The physics goals behind the RHIC are enumerated, particularly as regards the study of quark matter and the characteristics of high energy nucleus-nucleus collisions. The design of the collider and all its components is described, including the injector, the lattice, magnet system, cryogenic and vacuum systems, beam transfer, injection, and dump, rf system, and beam instrumentation and control system. Also given are cost estimates, construction schedules, and a management plan. (LEW)

  10. Center for Beam Physics papers

    SciTech Connect

    Sessler, A.M.

    1996-06-01

    Six papers are included in this collection. They cover: a second interaction region for gamma-gamma, gamma-electron and electron- electron collisions; constraints on laser-driven accelerators for a high-energy linear collider; progress on the design of a high luminosity muon-muon collider; RF power source development at the RTA test facility; sensitivity studies of crystalline beams; and single bunch collective effects in muon colliders.

  11. HIGH-ENERGY PARTICLE COLLIDERS: PAST 20 YEARS, NEXT 20 YEARS, AND BEYOND

    SciTech Connect

    Shiltsev, V.

    2013-09-25

    Particle colliders for high-energy physics have been in the forefront of scientific discoveries for more than half a century. The accelerator technology of the colliders has progressed immensely, while the beam energy, luminosity, facility size, and cost have grown by several orders of magnitude. The method of colliding beams has not fully exhausted its potential but has slowed down considerably in its progress. This paper briefly reviews the colliding beam method and the history of colliders, discusses the development of the method over the last two decades in detail, and examines near-term collider projects that are currently under development. The paper concludes with an attempt to look beyond the current horizon and to find what paradigm changes are necessary

  12. A conceptual design of Final Focus Systems for linear colliders

    SciTech Connect

    Brown, K.L.

    1987-06-01

    Linear colliders are a relatively recent development in the evolution of particle accelerators. This report discusses some of the approaches that have been considered for the design of Final Focus Systems to demagnify the beam exiting from a linac to the small size suitable for collisions at the interaction point. The system receiving the most attention is the one adopted for the SLAC Linear Collider. However, the theory and optical techniques discussed should be applicable to the design efforts for future machines.

  13. Potential-Well Distortion, Microwave Instability, and Their Effects with Colliding Beams at KEKB

    SciTech Connect

    Cai, Yunhai; Flanagan, J.; Fukuma, H.; Funakoshi, Y.; Ieiri, T.; Ohmi, K.; Oide, K.; Suetsugu, Y.; Rorie, Jamal; /Hawaii U.

    2009-04-01

    Microwave instability in the Low Energy Ring of KEKB was studied using a broadband impedance model. The model gave excellent descriptions of longitudinal dynamics for both positive and negative momentum compactions. Moreover, it predicted that the threshold of microwave instability was a factor of two lower than the machine nominal operating bunch current. The prediction was confirmed by a measurement using the Belle detector. Furthermore, we integrated the longitudinal wakefield into the beam-beam simulation and applied it to study the combined effects in KEKB. As a result, the beam-beam simulation became truly three-dimensional with emittance growth in all three dimensions simultaneously as the beam currents increase. In addition, an observed mystery of asymmetry in the horizontal scan could also be explained by our simulations.

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

    ScienceCinema

    Andrei Seryi

    2010-01-08

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

  15. Muon Muon Collider: Feasibility Study

    SciTech Connect

    Gallardo, J.C.; Palmer, R.B.; Tollestrup, A.V.; Sessler, A.M.; Skrinsky, A.N.; Ankenbrandt, C.; Geer, S.; Griffin, J.; Johnstone, C.; Lebrun, P.; McInturff, A.; Mills, Frederick E.; Mokhov, N.; Moretti, A.; Neuffer, D.; Ng, K.Y.; Noble, R.; Novitski, I.; Popovic, M.; Qian, C.; Van Ginneken, A. ,

    2012-04-05

    A feasibility study is presented of a 2 + 2 TeV muon collider with a luminosity of L = 10{sup 35} cm{sup -2}s{sup -1}. The resulting design is not optimized for performance, and certainly not for cost; however, it does suffice - we believe - to allow us to make a credible case, that a muon collider is a serious possibility for particle physics and, therefore, worthy of R and D support so that the reality of, and interest in, a muon collider can be better assayed. The goal of this support would be to completely assess the physics potential and to evaluate the cost and development of the necessary technology. The muon collider complex consists of components which first produce copious pions, then capture the pions and the resulting muons from their decay; this is followed by an ionization cooling channel to reduce the longitudinal and transverse emittance of the muon beam. The next stage is to accelerate the muons and, finally, inject them into a collider ring wich has a small beta function at the colliding point. This is the first attempt at a point design and it will require further study and optimization. Experimental work will be needed to verify the validity of diverse crucial elements in the design. Muons because of their large mass compared to an electron, do not produce significant synchrotron radiation. As a result there is negligible beamstrahlung and high energy collisions are not limited by this phenomena. In addition, muons can be accelerated in circular devices which will be considerably smaller than two full-energy linacs as required in an e{sup +} - e{sup -} collider. A hadron collider would require a CM energy 5 to 10 times higher than 4 TeV to have an equivalent energy reach. Since the accelerator size is limited by the strength of bending magnets, the hadron collider for the same physics reach would have to be much larger than the muon collider. In addition, muon collisions should be cleaner than hadron collisions. There are many detailed particle reactions which are open to a muon collider and the physics of such reactions - what one learns and the necessary luminosity to see interesting events - are described in detail. Most of the physics accesible to an e{sup +} - e{sup -} collider could be studied in a muon collider. In addition the production of Higgs bosons in the s-channel will allow the measurement of Higgs masses and total widths to high precision; likewise, t{bar t} and W{sup +}W{sup -} threshold studies would yield m{sub t} and m{sub w} to great accuracy. These reactions are at low center of mass energy (if the MSSM is correct) and the luminosity and {Delta}p/p of the beams required for these measurements is detailed in the Physics Chapter. On the other hand, at 2 + 2 TeV, a luminosity of L {approx} 10{sup 35} cm{sup -2}s{sup -1} is desirable for studies such as, the scattering of longitudinal W bosons or the production of heavy scalar particles. Not explored in this work, but worth noting, are the opportunities for muon-proton and muon-heavy ion collisions as well as the enormous richness of such a facility for fixed target physics provided by the intense beams of neutrinos, muons, pions, kaons, antiprotons and spallation neutrons. To see all the interesting physics described herein requires a careful study of the operation of a detector in the very large background. Three sources of background have been identified. The first is from any halo accompanying the muon beams in the collider ring. Very carefully prepared beams will have to be injected and maintained. The second is due to the fact that on average 35% of the muon energy appears in its decay electron. The energy of the electron subsequently is converted into EM showers either from the synchrotron radiation they emit in the collider magnetic field or from direct collision with the surrounding material. The decays that occur as the beams traverse the low beta insert are of particular concern for detector backgrounds. A third source of background is e{sup +} - e{sup -} pair creation from {mu}{sup +} - {mu}{sup -} interaction. Studies of how to shield the detector and reduce the background are addressed in the Detector Chapter. Polarization of the muons allows many very interesting measurements which are discussed in the Physics Chapter. Unlike the electron collider in which the electron beam is highly polarized and the positron beam unpolarized, both muon beams may be partially polarized. It is necessary to select forward moving muons from the pion's decay and thus reduce the available number of muons and hence the luminosity. The necessary machine technology needed to achieve such a collider is discussed in the Option Chapter; at the moment it is not part of our point design, although such capability would almost certainly be incorporated into an actual device.

  16. Acceleration of ampere class H- ion beam by MeV acceleratora)

    NASA Astrophysics Data System (ADS)

    Taniguchi, M.; Inoue, T.; Umeda, N.; Kashiwagi, M.; Watanabe, K.; Tobari, H.; Dairaku, M.; Sakamoto, K.

    2008-02-01

    The H- ion accelerator R&D to realize the international thermonuclear experimental reactor neutral beam is ongoing at Japan Atomic Energy Agency (JAEA). The required performance for the prototype MeV accelerator developed at JAEA is 1MeV, 500mA (current density of 200A/m2) H- ion beam at the beamlet divergence angle of less than 7mrad. Up to 2005, 836keV, 146A/m2 H- ion beam was successfully accelerated as the highest record of the current density at MeV class energy beams. In the present work, high current negative ion beam acceleration test was performed by increasing the beam extraction apertures from 33 (9 apertures) to 35 (15 apertures). By fixing the air leak at the source chamber due to backstream ions as well as the improvement of voltage holding capability by a new fiber reinforced plastic insulator ring, the performance of the MeV accelerator was improved. So far, H- ion beam of 320mA was successfully accelerated up to 796keV with the beam divergence angle of 5.5mrad. The accelerated drain current including the electron reaches close to the power supply limit for the MeV test facility. The heat flux by the backstream ion during the above beam acceleration was estimated to be 360W/cm2. The Cs leakage to the accelerator during the test campaign (Cs total input of 5.0g) was 0.26mg (7.0?g/cm2). This is considered to be the allowable level from the viewpoint of voltage holding.

  17. Voltage holding study of 1 MeV accelerator for ITER neutral beam injector

    SciTech Connect

    Taniguchi, M.; Kashiwagi, M.; Umeda, N.; Dairaku, M.; Takemoto, J.; Tobari, H.; Tsuchida, K.; Yamanaka, H.; Watanabe, K.; Kojima, A.; Hanada, M.; Sakamoto, K.; Inoue, T.

    2012-02-15

    Voltage holding test on MeV accelerator indicated that sustainable voltage was a half of that of ideal quasi-Rogowski electrode. It was suggested that the emission of the clumps is enhanced by a local electric field concentration, which leads to discharge initiation at lower voltage. To reduce the electric field concentration in the MeV accelerator, gaps between the grid supports were expanded and curvature radii at the support corners were increased. After the modifications, the accelerator succeeded in sustaining -1 MV in vacuum without beam acceleration. However, the beam energy was still limited at a level of 900 keV with a beam current density of 150 A/m{sup 2} (346 mA) where the 3 x 5 apertures were used. Measurement of the beam profile revealed that deflection of the H{sup -} ions was large and a part of the H{sup -} ions was intercepted at the acceleration grid. This causes high heat load on the grids and the breakdowns during beam acceleration. To suppress the direct interception, new grid system was designed with proper aperture displacement based on a 3D beam trajectory analysis. As the result, the beam deflection was compensated and the voltage holding during the beam acceleration was improved. Beam parameter of the MeV accelerator was increased to 980 keV, 185 A/m{sup 2} (427 mA), which is close to the requirement of ITER accelerator (1 MeV, 200 A/m{sup 2}).

  18. Acceleration, current amplification and emittance in MBE-4, an experimental beam induction linear accelerator for heavy ions

    SciTech Connect

    Warwick, A.I.; Gough, D.E.; Keefe, D.; Meuth, H.

    1988-10-01

    We report on the implementation of a second schedule of acceleration and current amplification in MBE-4. Control of the beam current within the bunch is improved over that in the first schedule by the addition of several small amplitude induction pulsers to compensate for acceleration errors and to control the ends of the bunch. Measurements of the longitudinal and transverse emittance are presented. 5 refs., 3 figs., 1 tab.

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

    SciTech Connect

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

    2013-12-15

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

  20. Beam shaping assembly optimization for (7)Li(p,n)(7)Be accelerator based BNCT.

    PubMed

    Minsky, D M; Kreiner, A J

    2014-06-01

    Within the framework of accelerator-based BNCT, a project to develop a folded Tandem-ElectroStatic-Quadrupole accelerator is under way at the Atomic Energy Commission of Argentina. The proposed accelerator is conceived to deliver a proton beam of 30mA at about 2.5MeV. In this work we explore a Beam Shaping Assembly (BSA) design based on the (7)Li(p,n)(7)Be neutron production reaction to obtain neutron beams to treat deep seated tumors. PMID:24345525

  1. Capture and Control of Laser-Accelerated Proton Beams: Experiment and Simulation

    SciTech Connect

    Nurnberg, F; Alber, I; Harres, K; Schollmeier, M; Roth, M; Barth, W; Eickhoff, H; Hofmann, I; Friedman, A; Grote, D; Logan, B G

    2009-05-13

    This paper summarizes the ongoing studies on the possibilities for transport and RF capture of laser-accelerated proton beams in conventional accelerator structures. First results on the capture of laser-accelerated proton beams are presented, supported by Trace3D, CST particle studio and Warp simulations. Based on these results, the development of the pulsed high-field solenoid is guided by our desire to optimize the output particle number for this highly divergent beam with an exponential energy spectrum. A future experimental test stand is proposed to do studies concerning the application as a new particle source.

  2. Flash X-Ray (FXR) Accelerator Optimization - Beam-induced Voltage Simulation and TDR Measurements

    SciTech Connect

    Ong, M M; Vogtlin, G E

    2004-04-07

    Lawrence Livermore National Laboratory (LLNL) is evaluating design alternatives to improve the voltage regulation in our Flash X-Ray (FXR) accelerator cell and pulse-power system. The goal is to create a more mono-energetic electron beam that will create an x-ray source with a smaller spot-size. Studying the interaction of the beam and accelerator cell will generate improved designs for high-current accelerators at Livermore and elsewhere. When an electron beam crosses the energized gap of an accelerator cell, the electron energy is increased. However, the beam with the associated electromagnetic wave also looses a small amount of energy because of the increased impedance seen across the gap. The phenomenon is sometimes called beam loading. It can also be described as a beam-induced voltage at the gap which is time varying. This creates beam energy variations that we need to understand and control. A high-fidelity computer simulation of the beam and cell interaction has been completed to quantify the time varying induced voltage at the gap. The cell and pulse-power system was characterized using a Time-domain Reflectometry (TDR) measurement technique with a coaxial air-line to drive the cell gap. The beam-induced cell voltage is computed by convoluting the cell impedance with measured beam current. The voltage was checked against other measurements to validate the accuracy. The simulation results predicted that there are significant beam-induced gap voltage variations. Beam-induced voltages from different current profiles and cell impedances were simulated and compared. This allows us to predict the effect on voltage regulation for different design alternatives before making hardware changes and high-voltage testing. The beam-induced voltages are incorporated into a larger accelerator system-model to quantify their effect on total beam energy variations.

  3. Strategies for mitigating the ionization-induced beam head erosion problem in an electron-beam-driven plasma wakefield accelerator

    NASA Astrophysics Data System (ADS)

    An, W.; Zhou, M.; Vafaei-Najafabadi, N.; Marsh, K. A.; Clayton, C. E.; Joshi, C.; Mori, W. B.; Lu, W.; Adli, E.; Corde, S.; Litos, M.; Li, S.; Gessner, S.; Frederico, J.; Hogan, M. J.; Walz, D.; England, J.; Delahaye, J. P.; Muggli, P.

    2013-10-01

    Strategies for mitigating ionization-induced beam head erosion in an electron-beam-driven plasma wakefield accelerator (PWFA) are explored when the plasma and the wake are both formed by the transverse electric field of the beam itself. Beam head erosion can occur in a preformed plasma because of a lack of focusing force from the wake at the rising edge (head) of the beam due to the finite inertia of the electrons. When the plasma is produced by field ionization from the space charge field of the beam, the head erosion is significantly exacerbated due to the gradual recession (in the beam frame) of the 100% ionization contour. Beam particles in front of the ionization front cannot be focused (guided) causing them to expand as in vacuum. When they expand, the location of the ionization front recedes such that even more beam particles are completely unguided. Eventually this process terminates the wake formation prematurely, i.e., well before the beam is depleted of its energy. Ionization-induced head erosion can be mitigated by controlling the beam parameters (emittance, charge, and energy) and/or the plasma conditions. In this paper we explore how the latter can be optimized so as to extend the beam propagation distance and thereby increase the energy gain. In particular we show that, by using a combination of the alkali atoms of the lowest practical ionization potential (Cs) for plasma formation and a precursor laser pulse to generate a narrow plasma filament in front of the beam, the head erosion rate can be dramatically reduced. Simulation results show that in the upcoming two-bunch PWFA experiments on the FACET facility at SLAC national accelerator laboratory the energy gain of the trailing beam can be up to 10 times larger for the given parameters when employing these techniques. Comparison of the effect of beam head erosion in preformed and ionization produced plasmas is also presented.

  4. Vibration Energy Harvester with Bi-stable Curved Beam Spring Offset by Gravitational Acceleration

    NASA Astrophysics Data System (ADS)

    Yamamoto, Koki; Fujita, Takayuki; Badel, Adrien; Formosa, Fabien; Kanda, Kensuke; Maenaka, Kazusuke

    2015-12-01

    We developed MEMS bi-stable spring for vibration energy harvester (VEH), which consists of intrinsically curved shape spring and gravitational acceleration. By applying the gravitational acceleration, the curved beam is offset to the gravity direction. It will make more symmetrical bi-stable motion and the symmetry is improved from 3.3 to 65.4%. We proposed that the combination between curved beam and gravity acceleration for decreasing snap- through acceleration. From the analytical result, we investigate the combination can effective to use for decreasing of snap-through force. We also fabricated the prototype device by using MEMS fabrication process. The frequency response for horizontal direction and the acceleration response for vertical direction are measured. The acceleration response shows that the gravitational acceleration improves the symmetry of snap-through force.

  5. DEVELOPMENT OF ACCELERATOR DATA REPORTING SYSTEM AND ITS APPLICATION TO TREND ANALYSIS OF BEAM CURRENT DATA

    SciTech Connect

    Padilla, M.J.; Blokland, W.

    2009-01-01

    Detailed ongoing information about the ion beam quality is crucial to the successful operation of the Spallation Neutron Source at Oak Ridge National Laboratory. In order to provide the highest possible neutron production time, ion beam quality is monitored to isolate possible problems or performance-related issues throughout the accelerator and accumulator ring. For example, beam current monitor (BCM) data is used to determine the quality of the beam transport through the accelerator. In this study, a reporting system infrastructure was implemented and used to generate a trend analysis report of the BCM data. The BCM data was analyzed to facilitate the identifi cation of monitor calibration issues, beam trends, beam abnormalities, beam deviations and overall beam quality. A comparison between transformed BCM report data and accelerator log entries shows promising results which represent correlations between the data and changes made within the accelerator. The BCM analysis report is one of many reports within a system that assist in providing overall beam quality information to facilitate successful beam operation. In future reports, additional data manipulation functions and analysis can be implemented and applied. Built-in and user-defi ned analytic functions are available throughout the reporting system and can be reused with new data.

  6. Future Hadron Super Colliders:. the Farthest Energy Frontier

    NASA Astrophysics Data System (ADS)

    Barletta, William A.

    2004-08-01

    Advances in superconducting materials and magnets, in accelerator physics, and in beam feedback, control and instrumentation systems allow us to consider the practical design of a proton collider with a discovery potential well beyond that of the Large Hadron Collider (LHC) currently being constructed at CERN. The ELOISATRON (ELN) (or Very Large Hadron Collider (VLHC)) represents what may well be the final step on the energy frontier of accelerator-based high energy physics. Despite the existence of detailed designs of the SSC (at 20 TeV per beam), more than 15 years of technical studies1 for an ELOISATRON (ELN) at 100 TeV per beam, and an extensive study2 of a Very Large Hadron Collider (VLHC) at FNAL, the economic practicality of a collider at 50 to 100 TeV per beam will remain uncertain until appropriate arc dipole designs have been tested in model magnet configurations. A vital step toward an affordable ELN is research now underway aimed at the upgrade of the Large Hadron Collider (LHC) at CERN.

  7. Performance of the SPS ring vacuum system for colliding beam operation

    SciTech Connect

    Angerth, B.; Flockhart, R.B.; Kouba, G.; Wahl, H.

    1983-08-01

    The SPS ring vacuum system was recently upgraded to the vacuum requirements for proton-antiproton collider operation. The new specification stipulated an average operating pressure in the ring of 3.10/sup -9/ mbar, to be reached within 10 days of pumping after a venting to air. The pressure is expressed in nitrogen equivalent gauge reading. Bakeout to rapidly reduce the gas desorption from the system cannot be used in the SPS, except at a few special positions which cover less than 5% of the ring circumference. The specified pumping time is much shorter than the time it usually takes for an unbaked vacuum system to reach its limit pressure. The pressure thus continues to fall for roughly 3 months from the beginning of a pumpdown and finally settles at about 7.10/sup -10/ mbar.

  8. Considerations of the low-velocity stage of a radioactive beams accelerator

    SciTech Connect

    Talbert, W.L.

    1992-12-01

    Studies of the low-velocity stages of a radioactive beams accelerator are summarized, highlighting the limitations of existing RFQ technology when applied to the specifications of the IsoSpin Laboratory.

  9. Application of radiofrequency superconductivity to accelerators for high-current ion beams

    SciTech Connect

    Delayen, J.R.; Bohn, C.L.; Kennedy, W.L.; Roche, C.T.; Sagalovsky, L.

    1992-12-31

    A development program is underway to apply rf superconductivity to the design of continuous-wave (cw) linear accelerators for high-current, high-brightness ion beam. During the last few years, considerable progress has been made both experimentally and theoretically toward this application. Recent tests of niobium resonators for ion acceleration have yielded average accelerating gradients as high as 18 MV/m. In an experiment with a radio-frequency quadrupole geometry, niobium was found to sustain cw peak surface electric fields as high as 128 MV/m over large (10 cm) surface areas. Theoretical studies of beam halo, cumulative beam breakup and alternating-phase focusing have also yielded important results. This paper su-summarizes the recent progress and identifies current and future work in the areas of superconducting accelerator technology for high-current ion beams.

  10. Application of radiofrequency superconductivity to accelerators for high-current ion beams

    SciTech Connect

    Delayen, J.R.; Bohn, C.L.; Kennedy, W.L.; Roche, C.T.; Sagalovsky, L.

    1992-01-01

    A development program is underway to apply rf superconductivity to the design of continuous-wave (cw) linear accelerators for high-current, high-brightness ion beam. During the last few years, considerable progress has been made both experimentally and theoretically toward this application. Recent tests of niobium resonators for ion acceleration have yielded average accelerating gradients as high as 18 MV/m. In an experiment with a radio-frequency quadrupole geometry, niobium was found to sustain cw peak surface electric fields as high as 128 MV/m over large (10 cm) surface areas. Theoretical studies of beam halo, cumulative beam breakup and alternating-phase focusing have also yielded important results. This paper su-summarizes the recent progress and identifies current and future work in the areas of superconducting accelerator technology for high-current ion beams.

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

    SciTech Connect

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

    2010-06-01

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

  12. On the polarized beam acceleration in medium energy synchrotrons

    SciTech Connect

    Lee, S.Y.

    1992-12-31

    This lecture note reviews physics of spin motion in a synchrotron, spin depolarization mechanisms of spin resonances, and methods of overcoming the spin resonances during acceleration. Techniques used in accelerating polarized ions in the low/medium energy synchrotrons, such as the ZGS, the AGS, SATURNE, and the KEK PS and PS Booster are discussed. Problems related to polarized proton acceleration with snakes or partial snake are also examined.

  13. Testing general relativity with laser accelerated electron beams

    SciTech Connect

    Gergely, L. A.; Harko, T.

    2012-07-09

    Electron accelerations of the order of 10{sup 21} g obtained by laser fields open up the possibility of experimentally testing one of the cornerstones of general relativity, the weak equivalence principle, which states that the local effects of a gravitational field are indistinguishable from those sensed by a properly accelerated observer in flat space-time. We illustrate how this can be done by solving the Einstein equations in vacuum and integrating the geodesic equations of motion for a uniformly accelerated particle.

  14. INTERACTION OF A 24 GEV PROTON BEAM IWHT A MUON COLLIDER MERCURY JET TARGET EXPERIMENTAL RESULTS AND THERMODYNAMIC ASSESSMENT.

    SciTech Connect

    SIMOS,N.; KIRK,H.; FINFROCK,C.; GREENE,G.; LUDEWIG,H.; MCDONALD,K.; MOKHOV,N.

    2001-11-11

    A muon collider or a neutrino factory based on a muon storage ring require intense beams of muons that can be generated by a 1-4 MW proton beam incident on a moving target inside a 20-T solenoid magnet, with a mercury jet as a preferred example. This paper addresses the thermodynamic interaction of the intense proton beam with the proposed mercury jet target, and the consequences of the generated pressure waves on the target integrity. Specifically, a 24 GeV proton beam with approximately 16 TP (1 TP = 10{sup 12} protons) per pulse and a pulse length of 2 ns will interact with a 1 cm diameter mercury jet within the 20-Tesla magnetic field. In one option, a train of six such proton pulses is to be delivered on target within 2 {micro}s, in which case the state of the mercury jet following the interaction with each pulse is critical. Using the equation of state for mercury from the SESAME library, in combination with the energy deposition rates calculated the by the hadron interaction code MARS, the induced 3-D pressure field in the target is estimated. The consequent pressure wave propagation and attenuation in the mercury jet is calculated using a transient analysis based on finite element modeling, and the state of the mercury jet at the time of arrival of the subsequent pulse is assessed. Issues associated with the use of a liquid metal jet as a target candidate are addressed. Lastly, some experimental results from the BNL E951 experiment are presented and discussed.

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

    SciTech Connect

    Kanunnikov, V.N.

    1982-09-01

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

  16. Measuring beam emittance for high-energy H/sup -/ accelerators

    SciTech Connect

    Kramer, S.L.; Moffett, D.R.

    1981-01-01

    A novel technique is presented for measuring the six-dimensional beam emittance for high-energy H/sup -/ accelerators in real time. This technique uses the single charge exchange cross section from thin and narrow foils (intercepting 1 to 3% of the beam) as a line source for measuring the divergence and momentum spectra for operating H/sup -/ accelerator beams. By scanning the foil across the beam, X, theta, and p beam density spectra and emittance can be determined. The introduction of a second foil provides the Y-phi emittance. Operational experience of this low cost emittance measuring device has been obtained from the 50-MeV H/sup -/ linear accelerator at Argonne National Laboratory, simultaneously with its use as an injector into the Rapid-Cycling Synchrotron (RCS).

  17. Electrostatic design and beam transport for a folded tandem electrostatic quadrupole accelerator facility for accelerator-based boron neutron capture therapy.

    PubMed

    Vento, V Thatar; Bergueiro, J; Cartelli, D; Valda, A A; Kreiner, A J

    2011-12-01

    Within the frame of an ongoing project to develop a folded Tandem-Electrostatic-Quadrupole (TESQ) accelerator facility for Accelerator-Based Boron Neutron Capture Therapy (AB-BNCT), we discuss here the electrostatic design of the machine, including the accelerator tubes with electrostatic quadrupoles and the simulations for the transport and acceleration of a high intensity beam. PMID:21339070

  18. Cherenkov interaction and post-acceleration experiments of high brightness electron beams from a pseudospark discharge

    NASA Astrophysics Data System (ADS)

    Yin, H.; Cross, A. W.; Phelps, A. D. R.; He, W.; Ronald, K.

    2004-08-01

    A pseudospark-sourced electron beam has two phases, an initial hollow cathode phase (HCP) beam followed by a conductive phase (CP) beam. The beam brightness was measured by a field-free collimator to be 10 9 and 10 11 A m -2 rad -2 for HCP beam and CP beam, respectively. The initial HCP beam from an eight-gap pseudospark discharge was applied in a Cherenkov interaction between the electron beam and the TM 01 mode of a 60-cm long alumina-lined waveguide. While the CP beam from a three-gap pseudospark discharge chamber was propagated and post-accelerated from about 200 V to more than 40 kV.

  19. Flyer Acceleration by Pulsed Ion Beam Ablation and Application for Space Propulsion

    SciTech Connect

    Harada, Nobuhiro; Buttapeng, Chainarong; Yazawa, Masaru; Kashine, Kenji; Jiang Weihua; Yatsui, Kiyoshi

    2004-02-04

    Flyer acceleration by ablation plasma pressure produced by irradiation of intense pulsed ion beam has been studied. Acceleration process including expansion of ablation plasma was simulated based on fluid model. And interaction between incident pulsed ion beam and a flyer target was considered as accounting stopping power of it. In experiments, we used ETIGO-II intense pulsed ion beam generator with two kinds of diodes; 1) Magnetically Insulated Diode (MID, power densities of <100 J/cm2) and 2) Spherical-focused Plasma Focus Diode (SPFD, power densities of up to 4.3 kJ/cm2). Numerical results of accelerated flyer velocity agreed well with measured one over wide range of incident ion beam energy density. Flyer velocity of 5.6 km/s and ablation plasma pressure of 15 GPa was demonstrated by the present experiments. Acceleration of double-layer target consists of gold/aluminum was studied. For adequate layer thickness, such a flyer target could be much more accelerated than a single layer. Effect of waveform of ion beam was also examined. Parabolic waveform could accelerate more efficiently than rectangular waveform. Applicability of ablation propulsion was discussed. Specific impulse of 7000{approx}8000 seconds and time averaged thrust of up to 5000{approx}6000N can be expected. Their values can be controllable by changing power density of incident ion beam and pulse duration.

  20. Sensitivity analysis of an asymmetric Monte Carlo beam model of a Siemens Primus accelerator.

    PubMed

    Schreiber, Eric C; Sawkey, Daren L; Faddegon, Bruce A

    2012-01-01

    The assumption of cylindrical symmetry in radiotherapy accelerator models can pose a challenge for precise Monte Carlo modeling. This assumption makes it difficult to account for measured asymmetries in clinical dose distributions. We have performed a sensitivity study examining the effect of varying symmetric and asymmetric beam and geometric parameters of a Monte Carlo model for a Siemens PRIMUS accelerator. The accelerator and dose output were simulated using modified versions of BEAMnrc and DOSXYZnrc that allow lateral offsets of accelerator components and lateral and angular offsets for the incident electron beam. Dose distributions were studied for 40 40 cm fields. The resulting dose distributions were analyzed for changes in flatness, symmetry, and off-axis ratio (OAR). The electron beam parameters having the greatest effect on the resulting dose distributions were found to be electron energy and angle of incidence, as high as 5% for a 0.25 deflection. Electron spot size and lateral offset of the electron beam were found to have a smaller impact. Variations in photon target thickness were found to have a small effect. Small lateral offsets of the flattening filter caused significant variation to the OAR. In general, the greatest sensitivity to accelerator parameters could be observed for higher energies and off-axis ratios closer to the central axis. Lateral and angular offsets of beam and accelerator components have strong effects on dose distributions, and should be included in any high-accuracy beam model. PMID:22402376

  1. Possibility of studying the electromagnetic properties of neutral pions in experiments in colliding electron-positron beams

    SciTech Connect

    Bel'kov, A.A.; Kuraev, E.A.; Pervushin, V.N.

    1984-12-01

    We consider the possibility of experimentally studying the low energy electromagnetic parameters of neutral pions in colliding e/sup +/e/sup -/ beams. The cross sections for the reactions e/sup +/e/sup -/..--> pi../sup 0/..pi../sup 0/..gamma.., e/sup +/e/sup -/..-->..e/sup +/e/sup -/..pi../sup 0/..pi../sup 0/, and e/sup +/e/sup -/..--> pi../sup 0/..pi../sup 0/ are estimated in the theory with broken chiral symmetry. The calculations show that these processes can be studied in existing e/sup +/e/sup -/ beams. Such experiments give model-independent information on the amplitude of the Compton effect on the neutral pion (..gamma gamma --> pi../sup 0/..pi../sup 0/) in the physical region of the ..pi pi.. interaction m/sup 2//sub pipi/>4m/sup 2//sub ..pi../. In this region the amplitude of the process ..gamma gamma --> pi../sup 0/..pi../sup 0/ is mainly determined by a sub-threshold anomaly related to pion rescattering.

  2. Colliding or co-rotating ion beams in storage rings for EDM search

    NASA Astrophysics Data System (ADS)

    Koop, I. A.

    2015-11-01

    A new approach to search for and measure the electric dipole moment (EDM) of the proton, deuteron and some other light nuclei is presented. The idea of the method is to store two ion beams, circulating with different velocities, in a storage ring with crossed electric and magnetic guiding fields. One beam is polarized and its EDM is measured using the so-called ‘frozen spin’ method. The second beam, which is unpolarized, is used as a co-magnetometer, sensitive to the radial component of the ring’s magnetic field. The particle’s magnetic dipole moment (MDM) couples to the radial magnetic field and mimics the EDM signal. Measuring the relative vertical orbit separation of the two beams, caused by the presence of the radial magnetic field, one can control the unwanted MDM spin precession. Examples of the parameters for EDM storage rings for protons and other species of ions are presented. The use of crossed electric and magnetic fields helps to reduce the size of the ring by a factor of 10–20. We show that the bending radius of such an EDM storage ring could be about 2–3 m. Finally, a new method of increasing the spin coherence time, the so-called ‘spin wheel’, is proposed and its applicability to the EDM search is discussed.

  3. Analysis of ion beam optics of tetrode accelerator for neutral beam injector on the experimental advanced superconducting Tokamak

    NASA Astrophysics Data System (ADS)

    Xie, Yahong; Hu, Chundong; Zhao, Hongwei

    2015-08-01

    The ion optics is very important for an accelerator. The tetrode accelerator with slot apertures was employed on the neutral beam injector (NBI) for the Experimental Advanced Superconducting Tokamak (EAST). The ion optics of ion source accelerator was simulated using the IGUN code. The results have shown that the accelerator with diamond cross section plasma grid can get lower divergence angle comparing with the one with circular cross section plasma girds. In this paper, the voltage applied on the gradient grid (80%, 83% and 86% of plasma grid voltage) and the gap between plasma grid and gradient gird, gradient grid and suppression grid were also changed to estimate the ion extraction efficiency and ion beam trajectory. The results are helpful for the development and optimization of EAST-NBI ion source.

  4. Beam instrumentation for future high intense hadron accelerators at Fermilab

    SciTech Connect

    Wendt, M.; Hu, M.; Tassotto, G.; Thurman-Keup, R.; Scarpine, V.; Shin, S.; Zagel, J.; /Fermilab

    2008-08-01

    High intensity hadron beams of up to 2 MW beam power are a key element of new proposed experimental facilities at Fermilab. Project X, which includes a SCRF 8 GeV H{sup -} linac, will be the centerpiece of future HEP activities in the neutrino sector. After a short overview of this, and other proposed projects, we present the current status of the beam instrumentation activities at Fermilab with a few examples. With upgrades and improvements they can meet the requirements of the new beam facilities, however design and development of new instruments is needed, as shown by the prototype and conceptual examples in the last section.

  5. Unveiling the orbital angular momentum and acceleration of electron beams.

    PubMed

    Shiloh, Roy; Tsur, Yuval; Remez, Roei; Lereah, Yossi; Malomed, Boris A; Shvedov, Vladlen; Hnatovsky, Cyril; Krolikowski, Wieslaw; Arie, Ady

    2015-03-01

    New forms of electron beams have been intensively investigated recently, including vortex beams carrying orbital angular momentum, as well as Airy beams propagating along a parabolic trajectory. Their traits may be harnessed for applications in materials science, electron microscopy, and interferometry, and so it is important to measure their properties with ease. Here, we show how one may immediately quantify these beams' parameters without need for additional fabrication or nonstandard microscopic tools. Our experimental results are backed by numerical simulations and analytic derivation. PMID:25793830

  6. Electron beam optimization using 3D printed gas cells in a laser-plasma accelerator

    NASA Astrophysics Data System (ADS)

    Behm, Keegan; Vargas, Michael; Schumaker, William; Zhao, Zhen; Chvykov, Vladimir; Maksimchuk, Anatoly; Yanovsky, Victor; Thomas, Alexander; Krushelnick, Karl

    2013-10-01

    Laser driven tabletop accelerators have made it possible to produce tunable relativistic beams of electrons. One of the ways in which these electron beams can be optimized is by changing the plasma environment that creates and accelerates the electrons. Using a rapid prototyped gas cell built with a 3D printer to create a relatively contained environment for the plasma has increased the electron beam pointing stability and has created more monoenergetic beams than what was achieved with a gas jet. Several different gas cell designs have been studied and tested to determine the optimum configuration and gas mixture for stable, monoenergetic electron beams. Two-staged gas cells have produced the highest quality electron beams with greatest pointing and beam stability. The purpose of the two-staged gas cell is to divide the laser wakefield acceleration process into two steps, an injection stage, where a helium-nitrogen mixture is used to inject more charge into the wake of the laser, and an acceleration stage where pure helium is used to create a plasma conducive for accelerating the electrons captured in the first stage.

  7. Analysis of secondary particle behavior in multiaperture, multigrid accelerator for the ITER neutral beam injector

    SciTech Connect

    Mizuno, T.; Taniguchi, M.; Kashiwagi, M.; Umeda, N.; Tobari, H.; Watanabe, K.; Dairaku, M.; Sakamoto, K.; Inoue, T.

    2010-02-15

    Heat load on acceleration grids by secondary particles such as electrons, neutrals, and positive ions, is a key issue for long pulse acceleration of negative ion beams. Complicated behaviors of the secondary particles in multiaperture, multigrid (MAMuG) accelerator have been analyzed using electrostatic accelerator Monte Carlo code. The analytical result is compared to experimental one obtained in a long pulse operation of a MeV accelerator, of which second acceleration grid (A2G) was removed for simplification of structure. The analytical results show that relatively high heat load on the third acceleration grid (A3G) since stripped electrons were deposited mainly on A3G. This heat load on the A3G can be suppressed by installing the A2G. Thus, capability of MAMuG accelerator is demonstrated for suppression of heat load due to secondary particles by the intermediate grids.

  8. CEBAF: The Continuous Electron Beam Accelerator Facility and its Physics Program

    SciTech Connect

    Mougey, Jean

    1992-01-01

    With the 4 GeV Continuous Electron Beam Accelerator Facility presently under construction in Newport News, Virginia, a new domain of nuclear and subnuclear phenomena can be investigated, mainly through coincidence experiments. An overview of the characteristic features of the accelerator and associated experimental equipment is given. Some examples of the physics programs are briefly described.

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

    SciTech Connect

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

    2004-06-01

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

  10. The accelerator facility of the Heidelberg Ion-Beam Therapy Centre (HIT)

    NASA Astrophysics Data System (ADS)

    Peters, Andreas

    The following sections are included: * Introduction * Beam parameters * General layout of the HIT facility * The accelerator chain in detail * Operational aspects of a particle therapy facility * 24/7 accelerator operation at 335 days per year * Safety and regulatory aspects * Status and perspectives * References

  11. Tevatron End-of-Run Beam Physics Experiments

    SciTech Connect

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

    2012-05-01

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

  12. A prototype of a beam steering assistant tool for accelerator operations

    SciTech Connect

    M. Bickley; P. Chevtsov

    2006-10-24

    The CEBAF accelerator provides nuclear physics experiments at Jefferson Lab with high quality electron beams. Three experimental end stations can simultaneously receive the beams with different energies and intensities. For each operational mode, the accelerator setup procedures are complicated and require very careful checking of beam spot sizes and positions on multiple beam viewers. To simplify these procedures and make them reproducible, a beam steering assistant GUI tool has been created. The tool is implemented as a multi-window control screen. The screen has an interactive graphical object window, which is an overlay on top of a digitized live video image from a beam viewer. It allows a user to easily create and edit any graphical objects consisting of text, ellipses, and lines, right above the live beam viewer image and then save them in a file that is called a beam steering template. The template can show, for example, the area within which the beam must always be on the viewer. Later, this template can be loaded in the interactive graphical object window to help accelerator operators steer the beam to the specified area on the viewer.

  13. Status of LBL/LLNL FEL (free electron laser) research for two beam accelerator applications

    SciTech Connect

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

    1989-03-01

    We review the status of free electron laser (FEL) research being conducted at LBL and LLNL as part of a broader program of research on two beam accelerators (TBAs). Induction accelerator-driven FELs for use as power sources for high-gradient accelerators are discussed, along with preliminary cost estimates for this type of power source. Finally, a promising new version of an FEL/TBA is described. 25 refs., 1 fig., 3 tabs.

  14. A NEW DIFFERENTIAL AND ERRANT BEAM CURRENT MONITOR FOR THE SNS* ACCELERATOR

    SciTech Connect

    Blokland, Willem; Peters, Charles C

    2013-01-01

    A new Differential and errant Beam Current Monitor (DBCM) is being implemented for both the Spallation Neutron Source's Medium Energy Beam Transport (MEBT) and the Super Conducting Linac (SCL) accelerator sections. These new current monitors will abort the beam when the difference between two toroidal pickups exceeds a threshold. The MEBT DBCM will protect the MEBT chopper target, while the SCL DBCM will abort beam to minimize fast beam losses in the SCL cavities. The new DBCM will also record instances of errant beam, such as beam dropouts, to assist in further optimization of the SNS Accelerator. A software Errant Beam Monitor was implemented on the regular BCM hardware to study errant beam pulses. The new system will take over this functionality and will also be able to abort beam on pulse-to-pulse variations. Because the system is based on the FlexRIO hardware and programmed in LabVIEW FPGA, it will be able to abort beam in about 5 us. This paper describes the development, implementation, and initial test results of the DBCM, as well as errant beam examples.

  15. Beam Based HOM Analysis of Accelerating Structures at the TESLA Test Facility Linac

    SciTech Connect

    Wendt, M.; Schreiber, S.; Castro, P.; Gossel, A.; Huning, M.; Devanz, G.; Jablonka, M.; Magne, C.; Napoly, O.; Baboi, N.; /SLAC

    2005-08-09

    The beam emittance in future linear accelerators for high energy physics and SASE-FEL applications depends highly on the field performance in the accelerating structures, i.e. the damping of higher order modes (HOM). Besides theoretical and laboratory analysis, a beam based analysis technique was established [1] at the TESLA Test Facility (TTF) linac. It uses a charge modulated beam of variable modulation frequency to excite dipole modes. This causes a modulation of the transverse beam displacement, which is observed at a downstream BPM and associated with a direct analysis of the modes at the HOM-couplers. A brief introduction of eigenmodes of a resonator and the concept of the wake potential is given. Emphasis is put on beam instrumentation and signal analysis aspects, required for this beam based HOM measurement technique.

  16. High-Energy Laser-Accelerated Electron Beams for Long-Range Interrogation

    SciTech Connect

    Cummingham, N. J.; Banerjee, Sudeep; Ramanathan, Vidya; Powell, Nathan; Chandler-Smith, Nate; Vane, C Randy; Schultz, David Robert; Pozzi, Sara; Clarke, Shaun; Beene, James R; Umstadter, Donald

    2009-01-01

    We are studying the use of 0.1 1.0 GeV laser-accelerated electron beams as active interrogation probes for long-standoff radiography or nuclear activation of concealed special nuclear material. Use of beams in this energy range is largely unexplored, but such beams could provide notable advantages over lower-energy beams and x-rays. High-energy laser-accelerated electrons exhibit large penetration range through air and solids, and low beam divergence for both direct beams and secondary Bremsstrahlung x-rays. We present laboratory measurements of radiography and activation, using the high-power Diodes laser system at the University of Nebraska, as well as MCNP and GEANT Monte Carlo simulation results used to aid experiment design and interpretation.

  17. Measurements of Transverse Beam Diffusion Rates in the Fermilab Tevatron Collider

    SciTech Connect

    Stancari, G.; Annala, G.; Johnson, T.R.; Still, D.A.; Valishev, A.; /Fermilab

    2011-08-01

    The transverse beam diffusion rate vs. particle oscillation amplitude was measured in the Tevatron using collimator scans. All collimator jaws except one were retracted. As the jaw of interest was moved in small steps, the local shower rates were recorded as a function of time. By using a diffusion model, the time evolution of losses could be related to the diffusion rate at the collimator position. Preliminary results of these measurements are presented.

  18. SLAC linear collider: the machine, the physics, and the future

    SciTech Connect

    Richter, B.

    1981-11-01

    The SLAC linear collider, in which beams of electrons and positrons are accelerated simultaneously, is described. Specifications of the proposed system are given, with calculated preditions of performance. New areas of research made possible by energies in the TeV range are discussed. (GHT)

  19. NSAC Recommends a Relativistic Heavy-Ion Collider.

    ERIC Educational Resources Information Center

    Physics Today, 1984

    1984-01-01

    Describes the plan submitted by the Nuclear Science Advisory Committee to the Department of Energy and National Science Foundation urging construction of an ultrarelativistic heavy-ion collider designed to accelerate nucleon beams of ions as heavy as uranium. Discusses the process of selecting the type of facility as well as siting. (JM)

  20. Development of a low-energy beam transport system at KBSI heavy-ion accelerator

    NASA Astrophysics Data System (ADS)

    Bahng, Jungbae; Lee, Byoung-Seob; Sato, Yoichi; Ok, Jung-Woo; Park, Jin Yong; Yoon, Jang-Hee; Choi, Seyong; Won, Mi-Sook; Kim, Eun-San

    2015-01-01

    The Korea Basic Science Institute has developed a heavy ion accelerator for fast neutron radiography [1]. To meet the requirements for fast neutron generation, we have developed an accelerator system that consists of an electron cyclotron resonance ion source (ECR-IS), low-energy beam transport (LEBT) system, radio-frequency quadrupole (RFQ), medium-energy beam transport system, and drift tube linac. In this paper, we present the development of the LEBT system as a part of the heavy ion accelerator system, which operates from the ECR-IS to the RFQ entrance.

  1. Determination of Longitudinal Phase Space in SLAC Main Accelerator Beams

    SciTech Connect

    Barnes, C.; Decker, F.-J.; Emma, P.; Hogan, M.J.; Iverson, R.; Krejcik, P.; O'Connell, C.L.; Siemann, R.; Walz, D.; Clayton, C.E.; Huang, C.; Johnson, D.K.; Joshi, C.; Lu, W.; Marsh, K.A.; Deng, S.; Katsouleas, T.; Muggli, P.; Oz, E.; /Southern California U.

    2005-06-07

    In the E164 Experiment at that Stanford Linear Accelerator Center (SLAC), we drive plasma wakes for electron acceleration using 28.5 GeV bunches from the main accelerator. These bunches can now be made with an RMS length of 12 microns, and accurate direct measurement of their lengths is not feasible shot by shot. Instead, we use an indirect technique, measuring the energy spectrum at the end of the linac and comparing with detailed simulations of the entire machine. We simulate with LiTrack, a 2D particle tracking code developed at SLAC. Understanding the longitudinal profile allows a better understanding of acceleration in the plasma wake, as well as investigation of related effects. We discuss the method and validation of our phase space determinations.

  2. Excitation of multipolar surface plasmon resonance in plasmonic nanoparticles by complex accelerating beams

    NASA Astrophysics Data System (ADS)

    Yang, Yang; Li, Jiafang; Li, Zhi-Yuan; Chen, Yue-Gang

    2015-07-01

    In this paper, through a vector-spherical harmonics approach, we investigate the optical spectra of plasmonic Au nanoparticles excited by two special accelerating beams: a non-paraxial Airy beam and a Bessel beam. We systematically analyze the impacts of the beam profile, phase, and helical wave front of the electromagnetic fields on the optical spectrum and the excitation of the surface plasmon resonance (SPR). We find that the high-order phase in the Airy beam would result in strong plasmonic oscillations in the optical spectra, while the cone angle and orbital angular momentum carried by the Bessel beam could be employed to engineer the plasmon modes excited in Au nanoparticles. Furthermore, the optical spectrum excited by a combined Airy-Bessel-Gauss beam is discussed. The study could help to deeply explore new ways to manipulate SPR in metal nanoparticles via the wave front engineering of optical beams for enhancing light-matter interaction and optical sensing performance.

  3. Design for an accelerator-based orthogonal epithermal neutron beam for boron neutron capture therapy.

    PubMed

    Allen, D A; Beynon, T D; Green, S

    1999-01-01

    This paper is concerned with the proposed Birmingham accelerator-based epithermal neutron beam for boron neutron capture therapy (BNCT). In particular, the option of producing a therapy beam at an orthogonal direction to the incoming protons is considered. Monte Carlo radiation transport simulations, both with and without a head phantom, have shown that an orthogonal beam geometry is not only acceptable but is indeed beneficial, in terms of a lower mean neutron energy and an enhanced therapeutic ratio for the same useful neutron fluence in the therapy beam. Typical treatment times for various beam options have been calculated, and range from 20 to 48 min with a 5 mA beam of 2.8 MeV protons, if the maximum photon-equivalent dose delivered to healthy tissue is to be 12.6 Gy Eq. The effects of proton beam diameter upon the therapy beam parameters have also been considered. PMID:9949400

  4. Two-screen single-shot electron spectrometer for laser wakefield accelerated electron beams

    SciTech Connect

    Soloviev, A. A.; Starodubtsev, M. V.; Burdonov, K. F.; Kostyukov, I. Yu.; Nerush, E. N.; Shaykin, A. A.; Khazanov, E. A.

    2011-04-15

    The laser wakefield acceleration electron beams can essentially deviate from the axis of the system, which distinguishes them greatly from beams of conventional accelerators. In case of energy measurements by means of a permanent-magnet electron spectrometer, the deviation angle can affect accuracy, especially for high energies. A two-screen single-shot electron spectrometer that correctly allows for variations of the angle of entry is considered. The spectrometer design enables enhancing accuracy of measuring narrow electron beams significantly as compared to a one-screen spectrometer with analogous magnetic field, size, and angular acceptance.

  5. System modeling for the longitudinal beam dynamics control problem in heavy ion induction accelerators

    SciTech Connect

    Payne, A.N.

    1993-05-17

    We address the problem of developing system models that are suitable for studying the control of the longitudinal beam dynamics in induction accelerators for heavy ions. In particular, we present the preliminary results of our efforts to devise a general framework for building detailed, integrated models of accelerator systems consisting of pulsed power modular circuits, induction cells, beam dynamics, and control system elements. Such a framework will permit us to analyze and design the pulsed power modulators and the control systems required to effect precise control over the longitudinal beam dynamics.

  6. Beam-turning magnet design and test for the Recirculating Linear Accelerator

    SciTech Connect

    Crow, J.T. ); Platt, R.C. )

    1991-01-01

    We have designed and tested a system for applying a ramped vertical magnetic field for turning the electron beam in the IFR Recirculating Linear Accelerator. The field is highly uniform over two Gaussian beam radii, and can be adjusted for a large radial gradient for increased energy bandwidth. The system includes shielding of the current-carrying rods to protect the pulser from REB induced fields and to reduce the effect of REB images on the beam transport to negligible levels. The system has been tested on the IBEX accelerator with > 95% peak current transport and > 90% charge transport through a 90{degree} turn. 2 refs., 6 figs.

  7. Industrial application of e-beam accelerators in Korea

    NASA Astrophysics Data System (ADS)

    Han, Bumsoo; Kim, JinKyu; Kim, Yuri; Jeong, Kwang-Young

    2012-07-01

    Electron Accelerators are the most common means of radiation processing, and they are used in diverse industries to enhance the physical and the chemical properties of materials and to reduce undesirable contaminants, such as pathogens or toxic by-products of materials. Fifteen thousand [1,500] electron accelerators are commercially used in the world, and this number is eight or nine times greater than the number of Gamma irradiation facilities. Electron accelerators are reliable and durable electrically-sourced equipment that can produce ionizing radiation when it is needed for a particular commercial use. Electron accelerators were introduced in Korea during the 1970s, firstly for research and later for insulated wire and cable production. At present, over sixty electron accelerators are in commercial use, providing several billion USD annually in Korean industries, mainly for purposes such as, productions of wires, cables, thermo-shrinkable materials, foam sheets, and coating, curing of materials, sterilization of medical products, environmental protection, and others. With the increasing needs in the automobile and electronics industries, applicable areas for electron accelerator will be extended greatly in the future.

  8. Reconstruction of Initial Beam Conditions at the Exit of the DARHT II Accelerator

    SciTech Connect

    Paul, A.C.

    2000-02-18

    We consider a technique of determining the initial beam conditions of the DARHT II accelerator by measuring the beam size under three different magnetic transport settings. This may be time gated to resolve the parameters as a function of time within the 2000 nsec pulse. This technique leads to three equations in three unknowns with solution giving the accelerator exit beam radius, tilt, and emittance. We find that systematic errors cancel and so are not a problem in the initial beam condition unfolding. Random uncorrelated shot to shot errors can be managed by one of three strategies: (1) make the transport system optically de-magnifying; (2) average over many individual shots; or (3) make the random uncorrelated shot to shot errors sufficiently small. The high power of the DARHT II beam requires that the beam transport system leading to a radius measuring apparatus be optically magnifying. This means that the shot to shot random errors must either be made small (less than about 1%) or that we average each of the three beam radius determinations over many individual shots. We find that for the anticipated DARHT II beam parameters that 60 to 120 shots should be sufficient to determine the accelerator beam parameters.

  9. Study of the transverse beam motion in the DARHT Phase II accelerator

    SciTech Connect

    Chen, Yu-Jiuan; Fawley, W M; Houck, T L

    1998-08-20

    The accelerator for the second-axis of the Dual Axis Radiographic Hydrodynamic Test (DARHT) facility will accelerate a 4-kA, 3-MeV, 2--s long electron current pulse to 20 MeV. The energy variation of the beam within the flat-top portion of the current pulse is (plus or equal to) 0.5%. The performance of the DARHT Phase II radiographic machine requires the transverse beam motion to be much less than the beam spot size which is about 1.5 mm diameter on the x-ray converter. In general, the leading causes of the transverse beam motion in an accelerator are the beam breakup instability (BBU) and the corkscrew motion. We have modeled the transverse beam motion in the DARHT Phase II accelerator with various magnetic tunes and accelerator cell configurations by using the BREAKUP code. The predicted sensitivity of corkscrew motion and BBU growth to different tuning algorithms will be presented.

  10. H-mode accelerating structures with permanent-magnet quadrupole beam focusing

    NASA Astrophysics Data System (ADS)

    Kurennoy, S. S.; Rybarcyk, L. J.; O'Hara, J. F.; Olivas, E. R.; Wangler, T. P.

    2012-09-01

    We have developed high-efficiency normal-conducting rf accelerating structures by combining H-mode resonator cavities and a transverse beam focusing by permanent-magnet quadrupoles (PMQ), for beam velocities in the range of a few percent of the speed of light. The shunt impedance of interdigital H-mode (IH-PMQ) structures is 10-20 times higher than that of a conventional drift-tube linac, while the transverse size is 4-5 times smaller. Results of the combined 3D modelingelectromagnetic computations, multiparticle beam-dynamics simulations with high currents, and thermal-stress analysisfor an IH-PMQ accelerator tank are presented. The accelerating-field profile in the tank is tuned to provide the best propagation of a 50-mA deuteron beam using coupled iterations of electromagnetic and beam-dynamics modeling. Measurements of a cold model of the IH-PMQ tank show a good agreement with the calculations. Examples of cross-bar H-mode structures with PMQ focusing for higher beam velocities are also presented. H-PMQ accelerating structures following a short radio-frequency quadrupole accelerator can be used both in the front end of ion linacs or in stand-alone applications.

  11. Instrumentation for diagnostics and control of laser-accelerated proton (ion) beams.

    PubMed

    Bolton, P R; Borghesi, M; Brenner, C; Carroll, D C; De Martinis, C; Fiorini, Francesca; Flacco, A; Floquet, V; Fuchs, J; Gallegos, P; Giove, D; Green, J S; Green, S; Jones, B; Kirby, D; McKenna, P; Neely, D; Nuesslin, F; Prasad, R; Reinhardt, S; Roth, M; Schramm, U; Scott, G G; Ter-Avetisyan, S; Tolley, M; Turchetti, G; Wilkens, J J

    2014-05-01

    Suitable instrumentation for laser-accelerated proton (ion) beams is critical for development of integrated, laser-driven ion accelerator systems. Instrumentation aimed at beam diagnostics and control must be applied to the driving laser pulse, the laser-plasma that forms at the target and the emergent proton (ion) bunch in a correlated way to develop these novel accelerators. This report is a brief overview of established diagnostic techniques and new developments based on material presented at the first workshop on 'Instrumentation for Diagnostics and Control of Laser-accelerated Proton (Ion) Beams' in Abingdon, UK. It includes radiochromic film (RCF), image plates (IP), micro-channel plates (MCP), Thomson spectrometers, prompt inline scintillators, time and space-resolved interferometry (TASRI) and nuclear activation schemes. Repetition-rated instrumentation requirements for target metrology are also addressed. PMID:24100298

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

    DOE PAGESBeta

    Ekdahl, Carl

    2015-11-17

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

  13. Rf System Requirements for JLabs MEIC Collider Ring

    SciTech Connect

    Wang, Shaoheng; Li, Rui; Rimmer, Robert A.; Wang, Haipeng; Zhang, Yuhong

    2013-06-01

    The Medium-energy Electron Ion Collider (MEIC), proposed by Jefferson Lab, consists of a series of accelerators. At the top energy are the electron and ion collider rings. For the ion ring, it accelerates five long ion bunches to colliding energy and rebunches ions into a train of very short bunches before colliding. A set of low frequency RF system is needed for the long ion bunch energy ramping. Another set of high frequency RF cavities is needed to rebunch ions. For the electron ring, superconducting RF (SRF) cavities are needed to compensate the synchrotron radiation energy loss. The impedance of the SRF cavities must be low enough to keep the high current electron beam stable. The preliminary design requirements of these RF cavities are presented.

  14. CHARACTERIZATION OF A HIGH CURRENT INDUCTION ACCELERATOR ELECTRON BEAM VIA OPTICAL TRANSITION RADIATION FROM DIELECTRIC FOILS

    SciTech Connect

    Tang, V; Brown, C; Houck, T

    2007-06-13

    Traditionally, thin metal foils are employed for optical transition radiation (OTR) beam diagnostics but the possibility of shorting accelerator insulating surfaces and modifying accelerating fields are concerns. The successful utilization of dielectric foils in place of metal ones could alleviate these issues but necessitates more understanding of the OTR data for inferring desired beam parameters because of the dielectric's finite permittivity. Additionally, the temperature dependence of the relevant foil parameters due to beam heating should be accounted for. Here, we present and discuss sample synthetic diagnostic results of Kapton OTR spot-size measurements from the Flash X-Ray (FXR) accelerator which studies these and sightline effects. These simulations show that in some cases, the observed spot-sizes and radii are noticeably larger than the beam radii.

  15. Self-accelerating Bessel-like beam generated by graded-index multimode fiber

    NASA Astrophysics Data System (ADS)

    Liu, Zhihai; Wei, Yong; Zhang, Yu; Liu, Chunlan; Zhang, Yaxun; Zhao, Enming; Yang, Jun; Yuan, Libo

    2015-12-01

    We propose and demonstrate a simple method to generate a Bessel-like beam by using a graded-index multimode fiber. We splice a single-mode fiber and a graded-index multimode fiber with a defined offset (?x=20 ?m), adjust the length (L) of the graded-index multimode fiber to be 400 ?m, and then we can produce a Bessel-like beam with the transverse acceleration of 0.15464 ?m-2. The Bessel-like beam has the transverse self-accelerating properties which provides a new method for micro particles to be transported in a bending trajectories. This transverse self-accelerating Bessel-like beam generator based on the graded-index multimode fiber constitutes a new development for high-precision micro particles experiments and manipulations with its simple structure, high integration and small size.

  16. Ultralow emittance, multi-MeV proton beams from a laser virtual-cathode plasma accelerator.

    PubMed

    Cowan, T E; Fuchs, J; Ruhl, H; Kemp, A; Audebert, P; Roth, M; Stephens, R; Barton, I; Blazevic, A; Brambrink, E; Cobble, J; Fernndez, J; Gauthier, J-C; Geissel, M; Hegelich, M; Kaae, J; Karsch, S; Le Sage, G P; Letzring, S; Manclossi, M; Meyroneinc, S; Newkirk, A; Ppin, H; Renard-LeGalloudec, N

    2004-05-21

    The laminarity of high-current multi-MeV proton beams produced by irradiating thin metallic foils with ultraintense lasers has been measured. For proton energies >10 MeV, the transverse and longitudinal emittance are, respectively, <0.004 mm mrad and <10(-4) eV s, i.e., at least 100-fold and may be as much as 10(4)-fold better than conventional accelerator beams. The fast acceleration being electrostatic from an initially cold surface, only collisions with the accelerating fast electrons appear to limit the beam laminarity. The ion beam source size is measured to be <15 microm (FWHM) for proton energies >10 MeV. PMID:15169357

  17. DTL cavity design and beam dynamics for a TAC linear proton accelerator

    NASA Astrophysics Data System (ADS)

    Caliskan, A.; Y?lmaz, M.

    2012-02-01

    A 30 mA drift tube linac (DTL) accelerator has been designed using SUPERFISH code in the energy range of 3-55 MeV in the framework of the Turkish Accelerator Center (TAC) project. Optimization criteria in cavity design are effective shunt impedance (ZTT), transit-time factor and electrical breakdown limit. In geometrical optimization we have aimed to increase the energy gain in each RF gap of the DTL cells by maximizing the effective shunt impedance (ZTT) and the transit-time factor. Beam dynamics studies of the DTL accelerator have been performed using beam dynamics simulation codes of PATH and PARMILA. The results of both codes have been compared. In the beam dynamical studies, the rms values of beam emittance have been taken into account and a low emittance growth in both x and y directions has been attempted.

  18. System tests with electric thruster beam and accelerator directly powered from laboratory solar arrays

    NASA Technical Reports Server (NTRS)

    Stover, J. B.

    1976-01-01

    Laboratory high voltage solar arrays were operated directly connected to power the beam and accelerator loads of an 8-centimeter ion thruster. The beam array comprised conventional 2 by 2 centimeter solar cells; the accelerator array comprised multiple junction edge-illuminated solar cells. Conventional laboratory power supplies powered the thruster's other loads. Tests were made to evaluate thruster performance and to investigate possible electrical interactions between the solar arrays and the thruster. Thruster performance was the same as with conventional laboratory beam and accelerator power supplies. Most of the thruster beam short circuits that occurred during solar array operation were cleared spontaneously without automatic or manual intervention. No spontaneous clearing occurred during conventional power supply operation.

  19. Emittance control of electron and positron beams in laser plasma accelerators

    NASA Astrophysics Data System (ADS)

    Yu, L.-L.; Schroeder, C. B.; Esarey, E.; Benedetti, Carlo; Vay, Jean-Luc; Chen, M.; Sheng, Z.-M.

    2015-05-01

    We propose to use a combination of Hermite-Gaussian laser modes to generate a nonlinear ring bubble with a large longitudinal accelerating field and a transverse focusing field suitable for positron beam focusing and acceleration. The nonlinear bubble can provide higher accelerating gradients compared with a linear plasma wake. PIC simulations have been used to demonstrate control of the focusing force by changing the relative intensity ratio of the two laser modes, enabling matched positron beam propagation for emittance preservation. In addition, in order to improve phase space characteristics of laser wakefield produced electron beams, in particular, to reduce their transverse emittance, we propose to generate femtosecond electron beams with ultralow emittance using a two-color laser-ionization injection method. By controlling the amplitude and the duration of the injection pulse, the emittance can be controlled to the level of 10-2 mm mrad.

  20. Cold ion beams in the low latitude boundary layer during accelerated flow events

    NASA Technical Reports Server (NTRS)

    Gosling, J. T.; Thomsen, M. F.; Bame, S. J.; Elphic, R. C.; Russell, C. T.

    1990-01-01

    Measurements made with the Fast Plasma Experiment on ISEE 1 and 2 reveal that accelerated beams of cold (1-30 eV for H/+/) ions are present sporadically on reconnected field lines within the low latitude boundary layer (LLBI). H(+) normally is the major constituent of these beams, but He(+) and O(+) are also occasionally detected in variable concentrations. Because of the low temperatures and the compositional makeup of these beams, the ionosphere must ultimately be the source of these ions. Observed beam speeds (between 120 and 250 km/s) are always less than that of the magnetosheath ions which penetrate into the LLBL on reconnected field lines, but both ion populations share the same E x B convective drift. Analysis reveals that reflection at the magnetopause cannot be the mechanism accelerating these ions. A more likely possibility is that the ions are accelerated primarily by the large transverse drift of recently reconnected field lines.

  1. Beam dynamics studies on the ISAC-II post-accelerator at TRIUMF.

    SciTech Connect

    Pasini, M.; Laxdal, R. E.; Ostroumov, P. N.

    2002-06-26

    The TRIUMF/ISAC facility, now a world leader in rare isotope production and acceleration, is constructing ISAC-II [1, 2], that will allow the acceleration of ion beams with 3 {le} A/q {le} 7 to an energy of at least 6.5 MeV/u for masses up to 150. The upgrade will include the addition of a superconducting heavy-ion linac delivering an effective voltage of 43 MV. The first order design of the new transfer lines and post-accelerator have been optimized to provide simultaneous acceleration of several charge states (multicharge). The quarter wave resonators providing the acceleration have inherent rf electric and magnetic asymmetric components that complicate multi-charge acceleration and can lead to transverse emittance growth. In particular we report the realistic field simulations of the medium beta section of the SC-DTL for multi-charge acceleration.

  2. Suppressing beam-centroid motion in a long-pulse linear induction accelerator

    NASA Astrophysics Data System (ADS)

    Ekdahl, Carl; Abeyta, E. O.; Archuleta, R.; Bender, H.; Broste, W.; Carlson, C.; Cook, G.; Frayer, D.; Harrison, J.; Hughes, T.; Johnson, J.; Jacquez, E.; McCuistian, B. Trent; Montoya, N.; Nath, S.; Nielsen, K.; Rose, C.; Schulze, M.; Smith, H. V.; Thoma, C.; Tom, C. Y.

    2011-12-01

    The second axis of the dual-axis radiography of hydrodynamic testing (DARHT) facility produces up to four radiographs within an interval of 1.6?s. It does this by slicing four micropulses out of a 2-?s long electron beam pulse and focusing them onto a bremsstrahlung converter target. The 1.8-kA beam pulse is created by a dispenser cathode diode and accelerated to more than 16 MeV by the unique DARHT Axis-II linear induction accelerator (LIA). Beam motion in the accelerator would be a problem for multipulse flash radiography. High-frequency motion, such as from beam-breakup (BBU) instability, would blur the individual spots. Low-frequency motion, such as produced by pulsed-power variation, would produce spot-to-spot differences. In this article, we describe these sources of beam motion, and the measures we have taken to minimize it. Using the methods discussed, we have reduced beam motion at the accelerator exit to less than 2% of the beam envelope radius for the high-frequency BBU, and less than 1/3 of the envelope radius for the low-frequency sweep.

  3. 3-D model of beam kicker in DARHT-2 accelerator

    NASA Astrophysics Data System (ADS)

    Thoma, Carsten; Genoni, Thomas; Hughes, Thomas

    2003-10-01

    The DARHT-2 beamline uses a fast stripline kicker developed at LLNL [1] to create a series of short pulses out of a 2 microsecond pulse for use in high resolution x-ray radiography. Normally, a static bias dipole bends the 2 kA, 18 MeV electron beam off axis into a dump. When the fast stripline kicker is activated, the static dipole kick is cancelled by the dynamic dipole field of the kicker, and the beam travels to the x-ray converter. 3-D PIC simulations are performed to compute the effect of the kicker on the beam. The calculations incorporate the kicker biplate conductor geometry, allowing for accurate modeling of the effects of higher multipole fields as well as beam wakefield effects. Beam emittance growth through the kicker is investigated for various beam loads. [1] B.R. Poole and Y.-J. Chen, "Particle Simulations of DARHT-2 Transport System", Proc. PAC 2001 Conference (http://accelconf.web.cern.ch/AccelConf/p01/PAPERS/RPPH034.PDF).

  4. Shock driven acceleration of impurity free ion beam using low density targets

    NASA Astrophysics Data System (ADS)

    Tresca, Olivier; Dover, Nicholas; Cook, Nathan; Maharjan, Chakra; Najmudin, Zulfikar; Polyanskiy, Mikhail; Shkolnikov, Peter; Pogorelsky, Igor; ATF Team; Blackett Laboratory Team; Stony Brook University Team

    2013-10-01

    Recent progress in COlaser technology has allowed for the creation of intense, 10 W cm-2, pulses at lambda ~10 μm. The longer wavelength of these pulses, compare to solid state lasers, allow for the use of low density targets, ~10 cm-3. In these conditions ion beams can be accelerated by a laser generated shock-wave to multi MeV energies with a narrow energy spread smaller than 10%. The CO laser at the Accelerator Test Facility has the unique capability of producing single, picoseconds-scale, pulses with 1 TW peak power, enabling us to study this acceleration regime in detail. The spatial density profile of the gas target has been found to be critical to the successful acceleration of ion beams. We report on recent PIC and fluid simulations results exploring the propagation of shock-wave and resulting ion acceleration for various plasma density profiles. Recent experimental results will also be discussed.

  5. Simultaneous observation of angularly separated laser-driven proton beams accelerated via two different mechanisms

    NASA Astrophysics Data System (ADS)

    Wagner, F.; Bedacht, S.; Bagnoud, V.; Deppert, O.; Geschwind, S.; Jaeger, R.; Ortner, A.; Tebartz, A.; Zielbauer, B.; Hoffmann, D. H. H.; Roth, M.

    2015-06-01

    We present experimental data showing an angular separation of laser accelerated proton beams. Using flat plastic targets with thicknesses ranging from 200 nm to 1200 nm, a laser intensity of 6 ×1020 W cm-2 incident with an angle of 10°, we observe accelerated protons in target normal direction with cutoff energies around 30 MeV independent from the target thickness. For the best match of laser and target conditions, an additional proton signature is detected along the laser axis with a maximum energy of 65 MeV. These different beams can be attributed to two acceleration mechanisms acting simultaneously, i.e., target normal sheath acceleration and acceleration based on relativistic transparency, e.g., laser breakout afterburner, respectively.

  6. The beat in laser-accelerated ion beams

    SciTech Connect

    Schnrer, M.; Abicht, F.; Brnzel, J.; Koschitzki, Ch.; Andreev, A. A.; Vavilov State Optical Institut, Birzhevaya line 12, 199064 St. Petersburg; St. Petersburg University, 199064 St. Petersburg, University emb.6 ; Platonov, K. Yu.; Priebe, G.; Sandner, W.; Technical University Berlin, Strae des 17. Juni 135, 10623 Berlin

    2013-10-15

    Regular modulation in the ion velocity distribution becomes detectable if intense femtosecond laser pulses with very high temporal contrast are used for target normal sheath acceleration of ions. Analytical and numerical analysis of the experimental observation associates the modulation with the half-cycle of the driving laser field period. In processes like ion acceleration, the collective and laser-frequency determined electron dynamics creates strong fields in plasma to accelerate the ions. Even the oscillatory motion of electrons and its influence on the acceleration field can dominate over smoothing effects in plasma if a high temporal contrast of the driving laser pulse is given. Acceleration parameters can be directly concluded out of the experimentally observed modulation period in ion velocity spectra. The appearance of the phenomenon at a temporal contrast of ten orders between the intensity of the pulse peak and the spontaneous amplified emission background as well as remaining intensity wings at picosecond time-scale might trigger further parameter studies with even higher contrast.

  7. Status of LBL/LLNL FEL (free electron laser) research for two beam accelerator applications

    SciTech Connect

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

    1988-11-01

    For this workshop, we review the status of free electron laser (FEL) research being conducted at LBL and LLNL as part of a broader program of research on two beam accelerators (TBAs). We discuss measurements made on high power 35 and 138 GHz FELs and their problem areas. Experience with 35 GHz accelerator section fabrication is summarized. Induction accelerator-driven FELs for use as power sources for high-gradient accelerators are discussed, along with preliminary cost estimates for this type of power source. Finally, a promising new version of an FEL/TBA is discussed. 22 refs., 7 figs., 5 tabs.

  8. Laser-driven multicharged heavy ion beam acceleration

    NASA Astrophysics Data System (ADS)

    Nishiuchi, M.; Sakaki, H.; Esirkepov, T. Z.; Nishio, K.; Pikuz, T. A.; Faenov, A. Y.; Pirozhkov, A. S.; Sagisaka, A.; Ogura, K.; Kanasaki, M.; Kiriyama, H.; Fukuda, Y.; Kando, M.; Yamauchi, T.; Watanabe, Y.; Bulanov, S. V.; Kondo, K.; Imai, K.; Nagamiya, S.

    2015-05-01

    Experimental demonstration of multi-charged heavy ion acceleration from the interaction between the ultra-intense short pulse laser system and the metal target is presented. The laser pulse of <10 J laser energy, 36 fs pulse width, and the contrast level of ~1010 from 200 TW class Ti:sapphire J-KAREN laser system at JAEA is used in the experiment. Almost fully stripped Fe ions accelerated up to 0.9 GeV are demonstrated. This is achieved by the high intensity laser field of 1021Wcm-2 interacting with the solid density target. The demonstrated iron ions with high charge to mass ratio (Q/M) is difficult to be achieved by the conventional heavy ion source technique in the accelerators.

  9. International linear collider reference design report

    SciTech Connect

    Aarons, G.

    2007-06-22

    The International Linear Collider will give physicists a new cosmic doorway to explore energy regimes beyond the reach of today's accelerators. A proposed electron-positron collider, the ILC will complement the Large Hadron Collider, a proton-proton collider at the European Center for Nuclear Research (CERN) in Geneva, Switzerland, together unlocking some of the deepest mysteries in the universe. With LHC discoveries pointing the way, the ILC -- a true precision machine -- will provide the missing pieces of the puzzle. Consisting of two linear accelerators that face each other, the ILC will hurl some 10 billion electrons and their anti-particles, positrons, toward each other at nearly the speed of light. Superconducting accelerator cavities operating at temperatures near absolute zero give the particles more and more energy until they smash in a blazing crossfire at the centre of the machine. Stretching approximately 35 kilometres in length, the beams collide 14,000 times every second at extremely high energies -- 500 billion-electron-volts (GeV). Each spectacular collision creates an array of new particles that could answer some of the most fundamental questions of all time. The current baseline design allows for an upgrade to a 50-kilometre, 1 trillion-electron-volt (TeV) machine during the second stage of the project. This reference design provides the first detailed technical snapshot of the proposed future electron-positron collider, defining in detail the technical parameters and components that make up each section of the 31-kilometer long accelerator. The report will guide the development of the worldwide R&D program, motivate international industrial studies and serve as the basis for the final engineering design needed to make an official project proposal later this decade.

  10. Concepts for the magnetic design of the MITICA neutral beam test facility ion accelerator

    SciTech Connect

    Chitarin, G.; Agostinetti, P.; Marconato, N.; Marcuzzi, D.; Sartori, E.; Serianni, G.; Sonato, P.

    2012-02-15

    The megavolt ITER injector concept advancement neutral injector test facility will be constituted by a RF-driven negative ion source and by an electrostatic Accelerator, designed to produce a negative Ion with a specific energy up to 1 MeV. The beam is then neutralized in order to obtain a focused 17 MW neutral beam. The magnetic configuration inside the accelerator is of crucial importance for the achievement of a good beam efficiency, with the early deflection of the co-extracted and stripped electrons, and also of the required beam optic quality, with the correction of undesired ion beamlet deflections. Several alternative magnetic design concepts have been considered, comparing in detail the magnetic and beam optics simulation results, evidencing the advantages and drawbacks of each solution both from the physics and engineering point of view.

  11. Spectrum shaping of accelerator-based neutron beams for BNCT

    NASA Astrophysics Data System (ADS)

    Montagnini, B.; Cerullo, N.; Esposito, J.; Giusti, V.; Mattioda, F.; Varone, R.

    2002-01-01

    We describe Monte Carlo simulations of three facilities for the production of epithermal neutrons for Boron Neutron Capture Therapy (BNCT) and examine general aspects and problems of designing the spectrum-shaping assemblies to be used with these neutron sources. The first facility is based on an accelerator-driven low-power subcritical reactor, operating as a neutron amplifier. The other two facilities have no amplifier and rely entirely on their primary sources, a D-T fusion reaction device and a conventional 2.5 MeV proton accelerator with a Li target, respectively.

  12. Electron pinch effect in beam-beam interaction of ERL based eRHIC

    SciTech Connect

    Hao,Y.; Litvinenko, V.N.; Ptitsyn, V.

    2009-05-04

    Beam-beam effects present one of major factors limiting the luminosity of colliders. In the linac-ring option of the eRHIC design, an electron beam accelerated in a superconducting energy recovery linac(ERL) collides with a proton beam circulating in the Rille ring. Some specific features of beam-beam interactions should be carefully evaluated for the linac-ring configuration. One of the most important effects on the ion beam stability originates from a strongly focus ed electron beam because of the beam-beam force. This electron pinch effect makes the beam-beam parameter of the ion beam several times larger than the design value, and leads to a fast emittance grow th of the ion beam. The electron pinch effect can be controlled by adjustments of the electron lattice and the incident emittance. We present results of simulations optimizing the ion beam parameters in the presence of this pinch effect.

  13. Multiple electron emission from noble gases colliding with proton beams, including postcollisional effects

    NASA Astrophysics Data System (ADS)

    Galassi, M. E.; Rivarola, R. D.; Fainstein, P. D.

    2007-05-01

    The process of multiple electron ionization of Ne and Ar noble gases produced by impact of proton beams is studied in the framework of the independent-electron model. The role played by different mechanisms is analyzed, including intershell Auger and intrashell Coster-Kronig electron emission, which follow the production of vacancies due to direct interaction of the projectile with the target electrons. The present results, obtained with the continuum distorted wave eikonal initial state (CDW-EIS) approximation, confirm previous predictions given by a different theoretical model. Semiempirical approximations are introduced by using analytical single-ionization probabilities with adjustable parameters determined from CDW-EIS total cross sections. The small computational time required to calculate multiple ionization cross sections with these semiempirical approximations and the good agreement found with existing experimental data and with results obtained with more elaborated theoretical models make them good candidates to study electron emission from complex targets.

  14. B meson physics with polarized electron beams at linear colliders running at the Z

    SciTech Connect

    Atwood, W.B.

    1988-12-01

    The expected large cross section for e e Z and subsequent decay to b/bar b/ quarks makes the Z an attractive placeto pursue B meson physics. The cross section for b-quark production at the Z is compared to resonance production at the UPSILON/sub 4s/ and UPSILON/sub 5s/. In addition the big electroweak asymmetries, thought to exist in Z decays to b/bar b/ quarks with polarized electron beams, provide an outstanding handle for observation of such effects as B - /bar B/ mixing. In this paper, the feasibility of such measurements is investigated and, with relatively small samples of Z's (a few hundred thousand), both B/sub d/ and B/sub s/ meson mixing are shown to be measurable. The subject of CP violation in neutral B mesons is discussed last, but presently such measurements seem to be out of reach. 7 refs., 7 figs., 3 tabs.

  15. Multiple electron emission from noble gases colliding with proton beams, including postcollisional effects

    SciTech Connect

    Galassi, M. E.; Rivarola, R. D.; Fainstein, P. D.

    2007-05-15

    The process of multiple electron ionization of Ne and Ar noble gases produced by impact of proton beams is studied in the framework of the independent-electron model. The role played by different mechanisms is analyzed, including intershell Auger and intrashell Coster-Kronig electron emission, which follow the production of vacancies due to direct interaction of the projectile with the target electrons. The present results, obtained with the continuum distorted wave-eikonal initial state (CDW-EIS) approximation, confirm previous predictions given by a different theoretical model. Semiempirical approximations are introduced by using analytical single-ionization probabilities with adjustable parameters determined from CDW-EIS total cross sections. The small computational time required to calculate multiple ionization cross sections with these semiempirical approximations and the good agreement found with existing experimental data and with results obtained with more elaborated theoretical models make them good candidates to study electron emission from complex targets.

  16. Transport of a high brightness proton beam through the Munich tandem accelerator

    NASA Astrophysics Data System (ADS)

    Moser, M.; Greubel, C.; Carli, W.; Peeper, K.; Reichart, P.; Urban, B.; Vallentin, T.; Dollinger, G.

    2015-04-01

    Basic requirement for ion microprobes with sub-μm beam focus is a high brightness beam to fill the small phase space usually accepted by the ion microprobe with enough ion current for the desired application. We performed beam transport simulations to optimize beam brightness transported through the Munich tandem accelerator. This was done under the constraint of a maximum ion current of 10 μA that is allowed to be injected due to radiation safety regulations and beam power constrains. The main influence of the stripper foil in conjunction with intrinsic astigmatism in the beam transport on beam brightness is discussed. The calculations show possibilities for brightness enhancement by using astigmatism corrections and asymmetric filling of the phase space volume in the x- and y-direction.

  17. Moment approach to high-order accelerator beam optics

    SciTech Connect

    Lysenko, W.P.

    1994-10-01

    High-current beams must be matched to high order to minimize emittance growth and particle losses. For matching problems, the moment approach, in which the author describes the particle beam by the moments of its distributions, is particularly valuable. A variety of analytical results are available for linear motion. The moment approach is also the basis of the 3-D space-charge simulation code BEDLAM, in which the dynamical variables are the moments. Moment simulation codes are particularly useful for computing beams matched to nonlinear systems. This paper outlines what is known about the moment approach, describes work in progress on new space-charge models, and describes further potential applications of and improvements to moment-method simulations.

  18. Relativistic electron transport in solids and high quality laser-accelerated proton beams

    NASA Astrophysics Data System (ADS)

    Cowan, T. E.; Allen, M. M.; Barton, I.; Stephens, R.; Roth, M.; Blazevic, A.; Geissel, M.; Schlegel, T.; Audebert, P.; Fuchs, J.; Gauthier, J.-C.; Hegelich, M.; Karsch, S.; Meyer-Ter-Vehn, J.; Pukhov, A.

    2001-10-01

    Intense, low emittance proton beams have been successfully generated in ultra-intense laser-matter interactions [1,2]. The exceptionally high quality of the beams [3] can be understood within the context of the Target Normal Sheath Acceleration (TNSA) process [4]. TNSA is driven by the relativistic electrons generated in the laser focus, which envelope the target foil and form a high density, hot electron sheath on the rear, non-irradiated surface. The strong electric field in the sheath region ionizes surface contaminants and preferentially accelerates the protons to several MeV energies within a picosecond over a few icron distance. The angular divergence of the highest energy protons depends on the spatial gradient of the density of the electron plasma sheath. We investigate the spatial uniformity of the relativistic electron transport through the solid density target foil by analysis of the sheath-accelerated proton beam. Disruption of the electron transport is observed depending on the electrical properties of the target material. We discuss the implications for the design of laser-accelerated ion sources and for ultra-high current relativistic electron transport in solids and plasmas, for example for fast ignition. [1] R. Snavely et al., Phys. Rev. Lett. 85, 2945 (2000). [2] M. Roth et al., submitted to Phys. Rev. Lett. (2001). [3] T.E. Cowan et al., "Laser Generation of Accelerator Quality Proton Beams," in: High Brightness Beams (World Scientific Press, Singapore, 2000). [4] S.C. Wilks et al., Phys. Plasmas 8, 532 (2001).

  19. Interactive visualization of particle beams for accelerator design

    SciTech Connect

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

    2002-01-15

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

  20. Treatment of industrial effluents using electron beam accelerator and adsorption with activated carbon: a comparative study

    NASA Astrophysics Data System (ADS)

    de Oliveira Sampa, Maria Helena; Rela, Paulo Roberto; Casas, Alexandre Las; Mori, Manoel Nunes; Duarte, Celina Lopes

    2004-09-01

    This paper presents preliminary results of a study that compares the use of electron beam processing and activated carbon adsorption to clean up a standardized organic aqueous solution and a real industrial effluent. The electron beam treatment was performed in a batch system using the IPEN's Electron Beam Accelerators from Radiation Dynamics Inc., Dynamitron 37.5 kW. The granular activated carbon removal treatment was performed using charcoal made from wood "pinus". If the adequate irradiation dose is delivered to the organic pollutant, it is possible to conclude for the studied compounds that the Electron Beam Process is similar to the activated carbon process in organic removal efficiency.