WorldWideScience

Sample records for beam transport simulations

  1. Simulation of a low energy beam transport line

    International Nuclear Information System (INIS)

    Yang Yao; Liu Zhanwen; Zhang Wenhui; Ma Hongyi; Zhang Xuezhen; Zhao Hongwei; Yao Ze'en

    2012-01-01

    A 2.45 GHz electron cyclotron resonance intense proton source and a low energy beam transport line with dual-Glaser lens were designed and fabricated by Institute of Modern Physics for a compact pulsed hadron source at Tsinghua. The intense proton beams extracted from the ion source are transported through the transport line to match the downstream radio frequency quadrupole accelerator. Particle-in-cell code BEAMPATH was used to carry out the beam transport simulations and optimize the magnetic field structures of the transport line. Emittance growth due to space charge and spherical aberrations of the Glaser lens were studied in both theory and simulation. The results show that narrow beam has smaller aberrations and better beam quality through the transport line. To better match the radio frequency quadrupole accelerator, a shorter transport line is desired with sufficient space charge neutralization. (authors)

  2. Injector and beam transport simulation study of proton dielectric wall accelerator

    International Nuclear Information System (INIS)

    Zhao, Quantang; Yuan, P.; Zhang, Z.M.; Cao, S.C; Shen, X.K.; Jing, Y.; Ma, Y.Y.; Yu, C.S.; Li, Z.P.; Liu, M.; Xiao, R.Q.; Zhao, H.W.

    2012-01-01

    A simulation study of a short-pulsed proton injector for, and beam transport in, a dielectric wall accelerator (DWA) has been carried out using the particle-in-cell (PIC) code Warp. It was shown that applying “tilt pulse” voltage waveforms on three electrodes enables the production of a shorter bunch by the injector. The fields in the DWA beam tube were simulated using Computer Simulation Technology’s Microwave Studio (CST MWS) package, with various choices for the boundary conditions. For acceleration in the DWA, the beam transport was simulated with Warp, using applied fields obtained by running CST MWS. Our simulations showed that the electric field at the entrance to the DWA represents a challenging issue for the beam transport. We thus simulated a configuration with a mesh at the entrance of the DWA, intended to improve the entrance field. In these latter simulations, a proton bunch was successfully accelerated from 130 keV to about 36 MeV in a DWA with a length of 36.75 cm. As the beam bunch progresses, its transverse dimensions diminish from (roughly) 0.5×0.5 cm to 0.2×0.4 cm. The beam pulse lengthens from 1 cm to 2 cm due to lack of longitudinal compression fields. -- Highlights: ► A pulse proton injector with tilt voltages on the three electrodes was simulated. ► The fields in different part of the DWA were simulated with CST and analyzed. ► The proton beam transport in DWA was simulated with Warp successfully. ► The simulation can help for designing a real DWA.

  3. Macrofilament simulation of high current beam transport

    International Nuclear Information System (INIS)

    Hayden, R.J.; Jakobson, M.J.

    1985-01-01

    Macrofilament simulation of high current beam transport through a series of solenoids has been used to investigate the sensitivity of such calculations to the initial beam distribution and to the number of filaments used in the simulation. The transport line was tuned to approximately 105 0 phase advance per cell at zero current with a tune depression of 65 0 due to the space charge. Input distributions with the filaments randomly uniform throughout a four dimensional ellipsoid and K-V input distributions have been studied. The behavior of the emittance is similar to that published for quadrupoles with like tune depression. The emittance demonstrated little growth in the first twelve solenoids, a rapid rate of growth for the next twenty, and a subsequent slow rate of growth. A few hundred filaments were sufficient to show the character of the instability. The number of filaments utilized is an order of magnitude fewer than has been utilized previously for similar instabilities. The previously published curves for simulations with less than a thousand particles show a rather constant emittance growth. If the solenoid transport line magnetic field is increased a few percent, emittance growth curves are obtained not unlike those curves. Collision growth effects are less important than indicated in the previously published results for quadrupoles

  4. Simulation and modeling of the Gamble II self-pinched ion beam transport experiment

    International Nuclear Information System (INIS)

    Rose, D.V.; Ottinger, P.F.; Hinshelwood, D.D.

    1999-01-01

    Progress in numerical simulations and modeling of the self-pinched ion beam transport experiment at the Naval Research Laboratory (NRL) is reviewed. In the experiment, a 1.2-MeV, 100-kA proton beam enters a 1-m long, transport region filled with a low pressure gas (30--250 mTorr helium, or 1 Torr air). The time-dependent velocity distribution function of the injected ion beam is determined from an orbit code that uses a pinch-reflex ion diode model and the measured voltage and current from this diode on the Gamble II generator at NRL. This distribution function is used as the beam input condition for numerical simulations carried out using the hybrid particle-in-cell code IPROP. Results of the simulations will be described, and detailed comparisons will be made with various measurements, including line-integrated electron-density, proton-fluence, and beam radial-profile measurements. As observed in the experiment, the simulations show evidence of self-pinching for helium pressures between 35 and 80 mTorr. Simulations and measurements in 1 Torr air show ballistic transport. The relevance of these results to ion-driven inertial confinement fusion will be discussed

  5. The theory and simulation of relativistic electron beam transport in the ion-focused regime

    International Nuclear Information System (INIS)

    Swanekamp, S.B.; Holloway, J.P.; Kammash, T.; Gilgenbach, R.M.

    1992-01-01

    Several recent experiments involving relativistic electron beam (REB) transport in plasma channels show two density regimes for efficient transport; a low-density regime known as the ion-focused regime (IFR) and a high-pressure regime. The results obtained in this paper use three separate models to explain the dependency of REB transport efficiency on the plasma density in the IFR. Conditions for efficient beam transport are determined by examining equilibrium solutions of the Vlasov--Maxwell equations under conditions relevant to IFR transport. The dynamic force balance required for efficient IFR transport is studied using the particle-in-cell (PIC) method. These simulations provide new insight into the transient beam front physics as well as the dynamic approach to IFR equilibrium. Nonlinear solutions to the beam envelope are constructed to explain oscillations in the beam envelope observed in the PIC simulations but not contained in the Vlasov equilibrium analysis. A test particle analysis is also developed as a method to visualize equilibrium solutions of the Vlasov equation. This not only provides further insight into the transport mechanism but also illustrates the connections between the three theories used to describe IFR transport. Separately these models provide valuable information about transverse beam confinement; together they provide a clear physical understanding of REB transport in the IFR

  6. Computer simulations for intense continuous beam transport in electrostatic lens systems

    International Nuclear Information System (INIS)

    Zhao Xiaosong; Lv Jianqin

    2008-01-01

    A code LEADS based on the Lie algebraic analysis for the continuous beam dynamics with space charge effect in beam transport has been developed. The program is used for the simulations of axial-symmetric and unsymmetrical intense continuous beam in the channels including drift spaces, electrostatic lenses and DC electrostatic accelerating tubes. In order to get the accuracy required, all elements are divided into many small segments, and the electric field in the segments is regarded as uniform field, and the dividing points are treated as thin lenses. Iteration procedures are adopted in the program to obtain self-consistent solutions. The code can be used in the designs of low energy beam transport systems, electrostatic accelerators and ion implantation machines. (authors)

  7. PATH: a lumped-element beam-transport simulation program with space charge

    International Nuclear Information System (INIS)

    Farrell, J.A.

    1983-01-01

    PATH is a group of computer programs for simulating charged-particle beam-transport systems. It was developed for evaluating the effects of some aberrations without a time-consuming integration of trajectories through the system. The beam-transport portion of PATH is derived from the well-known program, DECAY TURTLE. PATH contains all features available in DECAY TURTLE (including the input format) plus additional features such as a more flexible random-ray generator, longitudinal phase space, some additional beamline elements, and space-charge routines. One of the programs also provides a simulation of an Alvarez linear accelerator. The programs, originally written for a CDC 7600 computer system, also are available on a VAX-VMS system. All of the programs are interactive with input prompting for ease of use

  8. Numerical simulations of self-pinched transport of intense ion beams in low-pressure gases

    International Nuclear Information System (INIS)

    Rose, D.V.; Ottinger, P.F.; Welch, D.R.; Oliver, B.V.; Olson, C.L.

    1999-01-01

    The self-pinched transport of intense ion beams in low-pressure background gases is studied using numerical simulations and theoretical analysis. The simulations are carried out in a parameter regime that is similar to proton beam experiments being fielded on the Gamble II pulsed power generator [J. D. Shipman, Jr., IEEE Trans. Nucl. Sci. NS-18, 243 (1971)] at the Naval Research Laboratory. Simulation parameter variations provide information on scaling with background gas species, gas pressure, beam current, beam energy, injection angles, and boundaries. The simulation results compare well with simple analytic scaling arguments for the gas pressure at which the effective net current should peak and with estimates for the required confinement current. The analysis indicates that the self-pinched transport of intense proton beams produced on Gamble II (1.5 MeV, 100 kA, 3 cm radius) is expected to occur at gas pressures between 30 and 80 mTorr of He or between 3 and 10 mTorr of Ar. The significance of these results to ion-driven inertial confinement fusion is discussed. copyright 1999 American Institute of Physics

  9. High current beam transport with multiple beam arrays

    International Nuclear Information System (INIS)

    Kim, C.H.

    1985-05-01

    Highlights of recent experimental and theoretical research progress on the high current beam transport of single and multiple beams by the Heavy Ion Fusion Accelerator Research (HIFAR) group at the Lawrence Berkeley Laboratory (LBL) are presented. In the single beam transport experiment (SBTE), stability boundaries and the emittance growth of a space charge dominated beam in a long quadrupole transport channel were measured and compared with theory and computer simulations. Also, a multiple beam ion induction linac (MBE-4) is being constructed at LBL which will permit study of multiple beam transport arrays, and acceleration and bunch length compression of individually focused beamlets. Various design considerations of MBE-4 regarding scaling laws, nonlinear effects, misalignments, and transverse and longitudinal space charge effects are summarized. Some aspects of longitudinal beam dynamics including schemes to generate the accelerating voltage waveforms and to amplify beam current are also discussed

  10. Design and beam transport simulations of a multistage collector for the Israeli EA-FEM

    Science.gov (United States)

    Tecimer, M.; Canter, M.; Efimov, S.; Gover, A.; Sokolowski, J.

    2001-12-01

    A four stage asymmetric type depressed collector has been designed for the Israeli mm-wave FEM that is driven by a 1.4 MeV, 1.5 A electron beam. After leaving the interaction section the spent beam has an energy spread of 120 keV and 75 π mm mrad normalized beam emittance. Simulations of the beam transport system from the undulator exit through the decelerator tube into the collector have been carried out using EGUN and GPT codes. The latter has also been employed to study trajectories of the primary and scattered particles within the collector, optimizing the asymmetrical collector geometry and the electrode potentials at the presence of a deflecting magnetic field. The estimated overall system and collector efficiencies reach 50% and 70%, respectively, with a beam recovery of 99.6%. The design is aimed to attain millisecond long pulse operation and subsequently 1 kW average power. Simulation results are implemented in a mechanical design that leads to a simple, cost efficient assembly eliminating ceramic insulator rings between collector stages and the associated brazing in the manufacturing process. Instead, each copper plate is supported by insulating posts and freely displaceable within the vacuum chamber. We report on the simulation results of the beam transport and recovery systems and on the mechanical aspects of the multistage collector design.

  11. Design and beam transport simulations of a multistage collector for the Israeli EA-FEM

    Energy Technology Data Exchange (ETDEWEB)

    Tecimer, M. E-mail: tecimer@post.tau.ac.il; Canter, M.; Efimov, S.; Gover, A.; Sokolowski, J

    2001-12-21

    A four stage asymmetric type depressed collector has been designed for the Israeli mm-wave FEM that is driven by a 1.4 MeV, 1.5 A electron beam. After leaving the interaction section the spent beam has an energy spread of 120 keV and 75 {pi} mm mrad normalized beam emittance. Simulations of the beam transport system from the undulator exit through the decelerator tube into the collector have been carried out using EGUN and GPT codes. The latter has also been employed to study trajectories of the primary and scattered particles within the collector, optimizing the asymmetrical collector geometry and the electrode potentials at the presence of a deflecting magnetic field. The estimated overall system and collector efficiencies reach 50% and 70%, respectively, with a beam recovery of 99.6%. The design is aimed to attain millisecond long pulse operation and subsequently 1 kW average power. Simulation results are implemented in a mechanical design that leads to a simple, cost efficient assembly eliminating ceramic insulator rings between collector stages and the associated brazing in the manufacturing process. Instead, each copper plate is supported by insulating posts and freely displaceable within the vacuum chamber. We report on the simulation results of the beam transport and recovery systems and on the mechanical aspects of the multistage collector design.

  12. Design and beam transport simulations of a multistage collector for the Israeli EA-FEM

    International Nuclear Information System (INIS)

    Tecimer, M.; Canter, M.; Efimov, S.; Gover, A.; Sokolowski, J.

    2001-01-01

    A four stage asymmetric type depressed collector has been designed for the Israeli mm-wave FEM that is driven by a 1.4 MeV, 1.5 A electron beam. After leaving the interaction section the spent beam has an energy spread of 120 keV and 75 π mm mrad normalized beam emittance. Simulations of the beam transport system from the undulator exit through the decelerator tube into the collector have been carried out using EGUN and GPT codes. The latter has also been employed to study trajectories of the primary and scattered particles within the collector, optimizing the asymmetrical collector geometry and the electrode potentials at the presence of a deflecting magnetic field. The estimated overall system and collector efficiencies reach 50% and 70%, respectively, with a beam recovery of 99.6%. The design is aimed to attain millisecond long pulse operation and subsequently 1 kW average power. Simulation results are implemented in a mechanical design that leads to a simple, cost efficient assembly eliminating ceramic insulator rings between collector stages and the associated brazing in the manufacturing process. Instead, each copper plate is supported by insulating posts and freely displaceable within the vacuum chamber. We report on the simulation results of the beam transport and recovery systems and on the mechanical aspects of the multistage collector design

  13. Simulation of electron beam formation and transport in a gas-filled electron-optical system with a plasma emitter

    Energy Technology Data Exchange (ETDEWEB)

    Grishkov, A. A. [Russian Academy of Sciences, Institute of High Current Electronics, Siberian Branch (Russian Federation); Kornilov, S. Yu., E-mail: kornilovsy@gmail.com; Rempe, N. G. [Tomsk State University of Control Systems and Radioelectronics (Russian Federation); Shidlovskiy, S. V. [Tomsk State University (Russian Federation); Shklyaev, V. A. [Russian Academy of Sciences, Institute of High Current Electronics, Siberian Branch (Russian Federation)

    2016-07-15

    The results of computer simulations of the electron-optical system of an electron gun with a plasma emitter are presented. The simulations are performed using the KOBRA3-INP, XOOPIC, and ANSYS codes. The results describe the electron beam formation and transport. The electron trajectories are analyzed. The mechanisms of gas influence on the energy inhomogeneity of the beam and its current in the regions of beam primary formation, acceleration, and transport are described. Recommendations for optimizing the electron-optical system with a plasma emitter are presented.

  14. Investigations on transport and storage of high ion beam intensities

    International Nuclear Information System (INIS)

    Joshi, Ninad Shrikrishna

    2009-01-01

    In the framework of this thesis the intense low energy ion beam transport was investigated. Especially, the beam transport in toroidal magnetic field configurations was discussed, as it may allow the accumulation of high intensive beams in the future. One of the specific tasks is to design an injection system that can be used for the proposed low energy accumulator ring. A simulation code (TBT) was written to describe the particle motion in curved segments. Particle in Cell techniques were utilized to simulate a multi particle dynamics. A possibility of reading an external data file was made available so that a measured distribution can be used to compare simulation results with measured ones. A second order cloud in cell method was used to calculate charge density and in turn to solve Poisson's equation. Further simulations were performed to study the self field effects on beam transport. Experiments were performed to compare the simulation results and gain practical experience. The preparatory experiments consisted of building and characterization of the ion source in a first step. Along with the momentum spectrometer and emittance scanner the beam properties were studied. Low mass ion beams He + and mixed p, H 2+ , H 3+ beams were analyzed. In the second stage, beams were transported through a solenoid and the phase space distribution was measured as a function of the magnetic field for different beam energies. The phase-space as distributions measured in a first stage were simulated backward and then again forward transported through the solenoid. The simulated results were then compared with the measured distribution. The LINTRA transport program was used. The phase-space distribution was further simulated for transport experiments in a toroidal magnetic field. The transport program that was used to simulate the beam in the toroid was also used to design the injection system. The injection system with its special field configurations was designed to perform

  15. Investigations on transport and storage of high ion beam intensities

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, Ninad Shrikrishna

    2009-08-25

    In the framework of this thesis the intense low energy ion beam transport was investigated. Especially, the beam transport in toroidal magnetic field configurations was discussed, as it may allow the accumulation of high intensive beams in the future. One of the specific tasks is to design an injection system that can be used for the proposed low energy accumulator ring. A simulation code (TBT) was written to describe the particle motion in curved segments. Particle in Cell techniques were utilized to simulate a multi particle dynamics. A possibility of reading an external data file was made available so that a measured distribution can be used to compare simulation results with measured ones. A second order cloud in cell method was used to calculate charge density and in turn to solve Poisson's equation. Further simulations were performed to study the self field effects on beam transport. Experiments were performed to compare the simulation results and gain practical experience. The preparatory experiments consisted of building and characterization of the ion source in a first step. Along with the momentum spectrometer and emittance scanner the beam properties were studied. Low mass ion beams He{sup +} and mixed p, H{sup 2+}, H{sup 3+} beams were analyzed. In the second stage, beams were transported through a solenoid and the phase space distribution was measured as a function of the magnetic field for different beam energies. The phase-space as distributions measured in a first stage were simulated backward and then again forward transported through the solenoid. The simulated results were then compared with the measured distribution. The LINTRA transport program was used. The phase-space distribution was further simulated for transport experiments in a toroidal magnetic field. The transport program that was used to simulate the beam in the toroid was also used to design the injection system. The injection system with its special field configurations was

  16. Beam instability during high-current heavy-ion beam transport

    International Nuclear Information System (INIS)

    Kikuchi, T.; Someya, T.; Kawata, S.; Nakajima, M.; Horioka, K.

    2005-01-01

    In driver system for heavy ion inertial fusion, beam dynamics is investigated by particle-in-cell simulations during final beam bunching. The particle simulations predict that the beam is transported with the localized transverse charge distribution induced by the strong space charge effect. The calculation results also show that the emittance growth during the longitudinal bunch compression for various particle distributions at the initial conditions and with two types of transverse focusing model, which are a continuous focusing and an alternating gradient focusing lattice configurations. (author)

  17. Beam Extraction and Transport

    CERN Document Server

    Kalvas, T.

    2013-12-16

    This chapter gives an introduction to low-energy beam transport systems, and discusses the typically used magnetostatic elements (solenoid, dipoles and quadrupoles) and electrostatic elements (einzel lens, dipoles and quadrupoles). The ion beam emittance, beam space-charge effects and the physics of ion source extraction are introduced. Typical computer codes for analysing and designing ion optical systems are mentioned, and the trajectory tracking method most often used for extraction simulations is described in more detail.

  18. Simulation studies of the ion beam transport system in a compact electrostatic accelerator-based D-D neutron generator

    Directory of Open Access Journals (Sweden)

    Das Basanta Kumar

    2014-01-01

    Full Text Available The study of an ion beam transport mechanism contributes to the production of a good quality ion beam with a higher current and better beam emittance. The simulation of an ion beam provides the basis for optimizing the extraction system and the acceleration gap for the ion source. In order to extract an ion beam from an ion source, a carefully designed electrode system for the required beam energy must be used. In our case, a self-extracted penning ion source is used for ion generation, extraction and acceleration with a single accelerating gap for the production of neutrons. The characteristics of the ion beam extracted from this ion source were investigated using computer code SIMION 8.0. The ion trajectories from different locations of the plasma region were investigated. The simulation process provided a good platform for a study on optimizing the extraction and focusing system of the ion beam transported to the required target position without any losses and provided an estimation of beam emittance.

  19. Transport and matching of low energy space charge dominated beams

    International Nuclear Information System (INIS)

    Pandit, V.S.

    2013-01-01

    The transport and matching of low energy high intensity beams from the ion source to the subsequent accelerating structure are of considerable interest in recent years for variety of applications such as Accelerator driven system (ADSS), transmutation of nuclear waste, spallation neutron sources etc. It is essential to perform detailed simulations with experimentation to predict the beam evolution in the presence of nonlinear self as well as external fields before the design of the next accelerating structure is finalized. In order to study and settle various physics and technical issues related with transport of space charge dominated beams we have developed a 2.45 GHz microwave ion source at VECC which is now delivering more than 10 mA proton beam current at 80 keV. We have successfully transported well collimated 8 mA proton beam through the solenoid based 3 meter long transport line and studied various beam properties. We have also studied the transport of beam through spiral inflector at low beam current ∼ 1mA. In this article we will discuss the beam transport issues and describe a technique for simulation of beam envelopes in presence of linear space charge effects. We use canonical description of the motion of a single particle and then obtain first order differential equations for evolution of the moments of beam ensemble by assuming uniform distribution of the beam. We will also discuss the methodology used in the simulations to understand the observed beam behaviour during transport. (author)

  20. Ballistic-neutralized chamber transport of intense heavy ion beams

    International Nuclear Information System (INIS)

    Rose, D.V.; Welch, D.R.; Oliver, B.V.; Clark, R.E.; Sharp, W.M.; Friedman, A.

    2001-01-01

    Two-dimensional particle-in-cell simulations of intense heavy ion beams propagating in an inertial confinement fusion (ICF) reactor chamber are presented. The ballistic-neutralized transport scheme studied uses 4 GeV Pb +1 ion beams injected into a low-density, gas-filled reactor chamber and the beam is ballistically focused onto an ICF target before entering the chamber. Charge and current neutralization of the beam is provided by the low-density background gas. The ballistic-neutralized simulations include stripping of the beam ions as the beam traverses the chamber as well as ionization of the background plasma. In addition, a series of simulations are presented that explore the charge and current neutralization of the ion beam in an evacuated chamber. For this vacuum transport mode, neutralizing electrons are only drawn from sources near the chamber entrance

  1. Design and beam transport simulations of a multistage collector for the Israeli EA-FEM

    CERN Document Server

    Tecimer, M; Efimov, S; Gover, A; Sokolowski, J

    2001-01-01

    A four stage asymmetric type depressed collector has been designed for the Israeli mm-wave FEM that is driven by a 1.4 MeV, 1.5 A electron beam. After leaving the interaction section the spent beam has an energy spread of 120 keV and 75 pi mm mrad normalized beam emittance. Simulations of the beam transport system from the undulator exit through the decelerator tube into the collector have been carried out using EGUN and GPT codes. The latter has also been employed to study trajectories of the primary and scattered particles within the collector, optimizing the asymmetrical collector geometry and the electrode potentials at the presence of a deflecting magnetic field. The estimated overall system and collector efficiencies reach 50% and 70%, respectively, with a beam recovery of 99.6%. The design is aimed to attain millisecond long pulse operation and subsequently 1 kW average power. Simulation results are implemented in a mechanical design that leads to a simple, cost efficient assembly eliminating ceramic i...

  2. Generation and transport of laser accelerated ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Peter; Boine-Frankenheim, Oliver [Technische Univ. Darmstadt (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Kornilov, Vladimir; Spaedtke, Peter [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Collaboration: LIGHT-Collaboration

    2013-07-01

    Currently the LIGHT- Project (Laser Ion Generation, Handling and Transport) is performed at the GSI Helmholtzzentrum fuer Schwerionenforschung GmbH Darmstadt. Within this project, intense proton beams are generated by laser acceleration, using the TNSA mechanism. After the laser acceleration the protons are transported through the beam pipe by a pulsed power solenoid. To study the transport a VORPAL 3D simulation is compared with CST simulation. A criterion as a function of beam parameters was worked out, to rate the importance of space charge. Furthermore, an exemplary comparison of the solenoid with a magnetic quadrupole-triplet was carried out. In the further course of the LIGHT-Project, it is planned to generate ion beams with higher kinetic energies, using ultra-thin targets. The acceleration processes that can appear are: RPA (Radiation Pressure Acceleration) and BOA (Break-Out Afterburner). Therefore the transport of an ion distribution will be studied, as it emerges from a RPA acceleration.

  3. Self-pinched transport of intense ion beams

    International Nuclear Information System (INIS)

    Ottinger, P.F.; Neri, J.M.; Stephanakis, S.J.

    1999-01-01

    Electron beams with substantial net currents have been routinely propagated in the self-pinched mode for the past two decades. However, as the physics of gas breakdown and beam neutralization is different for ion beams, previous predictions indicated insufficient net current for pinching so that ion beam self-pinched transport (SPT) was assumed impossible. Nevertheless, recent numerical simulations using the IPROP code have suggested that ion SPT is possible. These results have prompted initial experiments to investigate SPT of ion beams. A 100-kA, 1.2-MeV, 3-cm-radius proton beam, generated on the Gamble II pulsed-power accelerator at NRL, has been injected into helium in the 30- to 250-mTorr regime to study this phenomenon. Evidence of self-pinched ion beam transport was observed in the 35- to 80-mTorr SPT pressure window predicted by IPROP. Measured signals from a time- and space-resolved scattered proton diagnostic and a time-integrated Li(Cu) nuclear activation diagnostic, both of which measure protons striking a 10-cm diameter target 50 cm into the transport region, are significantly larger in this pressure window than expected for ballistic transport. These results are consistent with significant self-magnetic fields and self-pinching of the ion beam. On the other hand, time-integrated signals from these same two diagnostics are consistent with ballistic transport at pressures above and below the SPT window. Interferometric electron line-density measurements, acquired during beam injection into the helium gas, show insignificant ionization below 35 mTorr, a rapidly rising ionization fraction with pressure in the SPT window, and a plateau in ionization fraction at about 2% for pressures above 80 mTorr. These and other results are consistent with the physical picture for SPT. IPROP simulations, which closely model the Gamble II experimental conditions, produce results that are in qualitative agreement with the experimental results. The advantages of SPT for

  4. Spatial dose and microdose distribution in tissues. Ionization, nuclear reactions, multiple scattering simulation of beam transport

    International Nuclear Information System (INIS)

    Jacquot, C.

    1976-01-01

    Computer simulation and nuclear emulsion and gelatin techniques enabled to give the total elastic and inelastic cross sections and to forecast the spatial microdose distributions in cells, nuclei and molecules. For this purpose, the transport of a beam into tissues having a given composition is calculated, the nuclear reactions are generated and the energy depositions in standard planes perpendicular to the beam are recorded

  5. Non-Linear Beam Transport System for the LENS 7 MeV Proton Beam

    CERN Document Server

    Jones, William P; Derenchuk, Vladimir Peter; Rinckel, Thomas; Solberg, Keith

    2005-01-01

    A beam transport system has been designed to carry a high-intensity low-emittance proton beam from the exit of the RFQ-DTL acceleration system of the Indiana University Low Energy Neutron System (LENS)* to the neutron production target. The goal of the design was to provide a beam of uniform density over a 3cm by 3cm area at the target. Two octupole magnets** are employed in the beam line to provide the necessary beam phase space manipulations to achieve this goal. First order calculations were done using TRANSPORT and second order calculations have been performed using TURTLE. Second order simulations have been done using both a Gaussian beam distribution and a particle set generated by calculations of beam transport through the RFQ-DTL using PARMILA. Comparison of the design characteristics with initial measurements from the LENS commissioning process will be made.

  6. Beam transport study of kA-class on the induction linac

    Energy Technology Data Exchange (ETDEWEB)

    Morimoto, Iwao; Zheng, Xiaodong; Maebara, Sunao; Shiho, Makoto [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kishiro, Jun-ichi; Takayama, Ken [High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan)

    2000-02-01

    Beam transport of kA-class for GW-class Free Electron Laser (FEL) was carried out through the two induction linacs (JLA). The first 1 MV induction linac was used as an electron beam generator, in which a carbon-cloth impregnated cold cathode was equipped and 1 MV, 160ns pulsed high voltage was immersed. About 1 kA high current electron beam was successfully generated and accelerated more 1 MeV by employing the following second induction linac. For kA-class high current beam generation and transportation, the most serious problem arises from the so strong space charge effect that the investigations to cure this effect both in the beam generation and the transportation are required. High rate beam loss comes from the strong space charge effect because the effect causes the unexpected beam blow up during the transportation. In the electron generator, the generated beam emittance was minimized with the program EGUN by choosing the geometry and shape of the cathode and anode electrode. In the beam transportation, a simulation program which included the space charge effect was developed. The simulation program was used to minimize and optimize the beam envelope oscillation through the beam transport line, and designed the configuration of the solenoid magnet channel. Experimentally, the electron beam of 450 A was extracted. The beam transport efficiency (beam current at outlet of accelerator/at inlet) reached to 90%, under the magnetic field of 1 kG. It was succeeded that the electron beam of 2 MeV - 400 A was transported with the mean beam diameter of 50 mm. (author)

  7. Self-pinched lithium beam transport experiments on SABRE

    International Nuclear Information System (INIS)

    Hanson, D.L.; Olson, C.L.; Poukey, J.W.; Shokir, I.; Cuneo, M.E.; Menge, P.R.; Johnston, R.R.; Welch, D.R.

    1996-01-01

    Self-pinched transport of ion beams has many advantages for ion-driven ICF applications involving high yield and energy production. The authors are currently preparing for a self-pinched lithium beam transport experiment on the SABRE accelerator. There are three transport elements that must eventually be demonstrated: (1) efficient lithium beam generation and ballistic transport to a focus at the self-pinched transport channel entrance; (2) self-pinched transport in the channel, requiring optimized injection conditions and gas breakdown; and (3) self-pinched transport of the equilibrated beam from the channel into free space, with associated aiming and stability considerations. In the present experiment, a hollow annular lithium beam from an applied-B extraction ion diode will be focused to small radius (r ≤ 2 cm) in a 60 cm long ballistic focus section containing argon gas at a pressure of a few Torr. The self-pinched transport channel will contain a low pressure background gas of 10--40 mTorr argon to allow sufficient net current to confine the beam for long distance transport. IPROP simulations are in progress to optimize the design of the ballistic and self-pinched transport sections. Progress on preparation of this lithium self-pinched transport experiment, including a discussion of transport system design, important gas breakdown issues, and diagnostics, will be presented

  8. Achromatic beam transport of High Current Injector

    International Nuclear Information System (INIS)

    Kumar, Sarvesh; Mandal, A.

    2016-01-01

    The high current injector (HCI) provides intense ion beams of high charge state using a high temperature superconducting ECR ion source. The ion beam is accelerated upto a final energy of 1.8 MeV/u due to an electrostatic potential, a radio frequency quadrupole (RFQ) and a drift tube linac (DTL). The ion beam has to be transported to superconducting LINAC which is around 50 m away from DTL. This section is termed as high energy beam transport section (HEBT) and is used to match the beam both in transverse and longitudinal phase space to the entrance of LINAC. The HEBT section is made up of four 90 deg. achromatic bends and interconnecting magnetic quadrupole triplets. Two RF bunchers have been used for longitudinal phase matching to the LINAC. The ion optical design of HEBT section has been simulated using different beam dynamics codes like TRACEWIN, GICOSY and TRACE 3D. The field computation code OPERA 3D has been utilized for hardware design of all the magnets. All the dipole and quadrupole magnets have been field mapped and their test results such as edge angles measurements, homogeneity and harmonic analysis etc. are reported. The whole design of HEBT section has been performed such that the most of the beam optical components share same hardware design and there is ample space for beam diagnostics as per geometry of the building. Many combination of achromatic bends have been simulated to transport the beam in HEBT section but finally the four 90 deg. achromatic bend configuration is found to be the best satisfying all the geometrical constraints with simplified beam tuning process in real time

  9. Overview of the APT high-energy beam transport and beam expanders

    International Nuclear Information System (INIS)

    Shafer, R.E.; Blind, B.; Gray, E.R.

    1997-01-01

    The APT high energy beam transport (HEBT) and beam expanders convey the 1700-MeV, 100-mA cw proton beam from the linac to the tritium target/blanket assembly, or a tuning beam stop. The HEBT includes extensive beam diagnostics, collimators, and beam jitter correction, to monitor and control the 170-MW beam prior to expansion. A zero-degree beamline conveys the beam to the beam stop, and an achromatic bend conveys the beam to the tritium production target. Nonlinear beam expanders make use of higher-order multipole magnets and dithering dipoles to expand the beam to a uniform-density, 16-cm wide by 160-cm high rectangular profile on the tritium-production target. The overall optics design will be reviewed, and beam simulations will be presented

  10. Performance test results of ion beam transport for SST-1 neutral beam injector

    Energy Technology Data Exchange (ETDEWEB)

    Jana, M R; Mattoo, S K [Institute for Plasma Research Bhat, Gandhinagar-382428, Gujarat (India); Uhlemann, R, E-mail: mukti@ipr.res.i [Forschungszentrum Juelich, Institute fur Energieforschung IEF-4, Plasmaphysik D-52425 Juelich (Germany)

    2010-02-01

    A neutral beam injector is built at IPR to heat the plasma of SST-1 and its upgrade. It delivers a maximum beam power of 1.7 MW for 55 kV Hydrogen beam or 80 kV Deuterium beam. At lower beam voltage, the delivered power falls to 500 kW at 30 kV Hydrogen beam which is adequate to heat SST-1 plasma ions to {approx} 1 keV. Process of acceleration of ions to the required beam voltage, conversion of ions to neutrals and removal of un-neutralized ions and the beam diagnostic systems occupy a large space. The consequence is that linear extent of the neutral beam injector is at least a few meters. Also, port access provides a very narrow duct. Even a very good injector design and fabrication practices keep beam divergence at a very low but finite value. The result is beam transport becomes an important issue. Since a wide area beam is constructed by hundreds of beam lets, it becomes essential they be focused in such a way that beam transport loss is minimized. Horizontal and vertical focal lengths are two parameters, in addition to beam divergence, which give a description of the beam transport. We have obtained these two parameters for our injector by using beam transport code; making several hundred simulation runs by varying optical parameters of the beam. The selected parameters set has been translated into the engineering features of the extractor grid set of the ion source. Aperture displacement technique is used to secure the horizontal beam focusing at 5.4 m. Combination of both aperture displacement and inclining of two grid halves to {approx} 17 mrad are secured for vertical beam focusing at 7 m from earth grid of the ion source. The gaps between the design, engineered and performance tested values usually arise due to lack of exercising control over fabrication processes or due to inaccuracies in the assumption made in the model calculations of beam optics and beam transport. This has been the case with several injectors, notably with JET injector. To overcome

  11. High performance stream computing for particle beam transport simulations

    International Nuclear Information System (INIS)

    Appleby, R; Bailey, D; Higham, J; Salt, M

    2008-01-01

    Understanding modern particle accelerators requires simulating charged particle transport through the machine elements. These simulations can be very time consuming due to the large number of particles and the need to consider many turns of a circular machine. Stream computing offers an attractive way to dramatically improve the performance of such simulations by calculating the simultaneous transport of many particles using dedicated hardware. Modern Graphics Processing Units (GPUs) are powerful and affordable stream computing devices. The results of simulations of particle transport through the booster-to-storage-ring transfer line of the DIAMOND synchrotron light source using an NVidia GeForce 7900 GPU are compared to the standard transport code MAD. It is found that particle transport calculations are suitable for stream processing and large performance increases are possible. The accuracy and potential speed gains are compared and the prospects for future work in the area are discussed

  12. Parallel Beam-Beam Simulation Incorporating Multiple Bunches and Multiple Interaction Regions

    CERN Document Server

    Jones, F W; Pieloni, T

    2007-01-01

    The simulation code COMBI has been developed to enable the study of coherent beam-beam effects in the full collision scenario of the LHC, with multiple bunches interacting at multiple crossing points over many turns. The program structure and input are conceived in a general way which allows arbitrary numbers and placements of bunches and interaction points (IP's), together with procedural options for head-on and parasitic collisions (in the strong-strong sense), beam transport, statistics gathering, harmonic analysis, and periodic output of simulation data. The scale of this problem, once we go beyond the simplest case of a pair of bunches interacting once per turn, quickly escalates into the parallel computing arena, and herein we will describe the construction of an MPI-based version of COMBI able to utilize arbitrary numbers of processors to support efficient calculation of multi-bunch multi-IP interactions and transport. Implementing the parallel version did not require extensive disruption of the basic ...

  13. VIVITRON beam transport

    International Nuclear Information System (INIS)

    Nadji, A.

    1989-07-01

    The VIVITRON is a new 35 MV particle accelerator which presents a great number of innovations. One of the major problem is the beam transport in this electrostatic machine of 50 m length for ions with masses between 1 and 200. Our work consisted in the study of various experimental and theoretical aspects of the beam transport in Tandem accelerators from the ion source to the analysing magnet. Calculations of the beam optics were performed with a Strasbourg version of the computer code Transport. They allowed us to optimize the beam transport parameters of the VIVITRON elements. Special attention has been focused on the design of the charge state selector to be installed in the terminal of the new machine. Beam transmission measurements were carried out in the Strasbourg MP 10 Tandem accelerator for ions beams of masses between 1 and 127 and for terminal voltages from 9 to 15 MV. Partial and total transmissions were obtained and explanations of the beam losses were proposed in terms of the vacuum pressure and/or the optics of the beam accelerator system. The results have been extrapolated to the VIVITRON for which the best working conditions are now clearly defined [fr

  14. Simulations of intense heavy ion beams propagating through a gaseous fusion target chamber

    International Nuclear Information System (INIS)

    Welch, D.R.; Rose, D.V.; Oliver, B.V.; Genoni, T.C.; Clark, R.E.; Olson, C.L.; Yu, S.S.

    2002-01-01

    In heavy-ion inertial confinement fusion (HIF), an ion beam is transported several meters through the reactor chamber to the target. This standoff distance mitigates damage to the accelerator from the target explosion. For the high perveance beams and millimeter-scale targets under consideration, the transport method is largely determined by the degree of ion charge and current neutralization in the chamber. This neutralization becomes increasingly difficult as the beam interacts with the ambient chamber environment and strips to higher charge states. Nearly complete neutralization permits neutralized-ballistic transport (main-line HIF transport method), where the ion beam enters the chamber at roughly 3-cm radius and focuses onto the target. In the backup pinched-transport schemes, the beam is first focused outside the chamber before propagating at small radius to the target. With nearly complete charge neutralization, the large beam divergence is contained by a strong magnetic field resulting from roughly 50-kA net current. In assisted-pinched transport, a preformed discharge channel provides the net current and the discharge plasma provides nearly complete charge and current neutralization of the beam. In self-pinched transport, the residual net current results solely from the beam-driven breakdown of the ambient gas. Using hybrid particle-in-cell simulation codes, the behavior of HIF driver-scale beams in these three transport modes is examined. Simulations of neutralized ballistic transport, at a few-mTorr flibe pressure, show excellent neutralization given a preformed or photoionized (from the heated target) plasma. Two- and three-dimensional simulations of assisted-pinch transport in roughly 1-Torr Xe show the importance of attaining >1-μs magnetic diffusion time to limit self-field effects and achieve good transport efficiency. For Xe gas pressures ranging from 10-150 mTorr, calculations predict a robust self-magnetic force sufficient for self

  15. Simulation and beam line experiments for the superconducting ECR ion source VENUS

    International Nuclear Information System (INIS)

    Todd, Damon S.; Leitner, Daniela; Grote, David P.; Lyneis, ClaudeM.

    2007-01-01

    The particle-in-cell code Warp has been enhanced to incorporate both two- and three-dimensional sheath extraction models giving Warp the capability of simulating entire ion beam transport systems including the extraction of beams from plasma sources. In this article we describe a method of producing initial ion distributions for plasma extraction simulations in electron cyclotron resonance (ECR) ion sources based on experimentally measured sputtering on the source biased disc. Using this initialization method, we present preliminary results for extraction and transport simulations of an oxygen beam and compare them with experimental beam imaging on a quartz viewing plate for the superconducting ECR ion source VENUS

  16. Phenomenological studies of electron-beam transport in wire-plasma channels

    International Nuclear Information System (INIS)

    Lockwood, G.J.; Beezhold, W.

    1980-01-01

    Multiple electron-beam transport in air through plasma channels is an important method for delivering many intense beams to a bremsstrahlung converter system. This paper reports work intended to optimize this transport technique with emphasis on transport through curved channels and on transport efficiencies. Curved-channel transport allows accelerators such as Sandia's PROTO II and PBFA I facilities to be used as flash x-ray sources for weapon effects simulation without reconfiguring the diodes or developing advanced converters. The formation mechanisms of wire-initiated plasma channels in air were examined and the subsequent transport efficiencies of relativistic electron beams through various-length straight and curved plasma channels were determined. Electron transport efficiency through a channel was measured to be 80 to 100% of a zero length channel for 40 cm long straight channels and for curved channels which re-directed the electron beam through an angle of 90 0 . Studies of simultaneous e-beam transport along two curved channels closely spaced at the converter showed that transport efficiency remained at 80 to 100%. However, it was observed that the two e-beams were displaced towards each other. Transport efficiency was observed to depend only weakly on parameters such as wire material, wire length and shape, diode anode aperture, e-beam injection time, and wire-channel applied voltage. For off-center injection conditions the electron beam strongly perturbed the plasma channel in periodic or regularly spaced patterns even though the total energy lost by the electron beam remained small. Plasma-channel transport, when all experimental parameters have been optimized for maximum transport efficiency, is a workable method for directing electron beams to a converter target

  17. Self-consistent study of space-charge-dominated beams in a misaligned transport system

    International Nuclear Information System (INIS)

    Sing Babu, P.; Goswami, A.; Pandit, V.S.

    2013-01-01

    A self-consistent particle-in-cell (PIC) simulation method is developed to investigate the dynamics of space-charge-dominated beams through a misaligned solenoid based transport system. Evolution of beam centroid, beam envelope and emittance is studied as a function of misalignment parameters for various types of beam distributions. Simulation results performed up to 40 mA of proton beam indicate that centroid oscillations induced by the displacement and rotational misalignments of solenoids do not depend of the beam distribution. It is shown that the beam envelope around the centroid is independent of the centroid motion for small centroid oscillation. In addition, we have estimated the loss of beam during the transport caused by the misalignment for various beam distributions

  18. Beam-transport study of an isocentric rotating ion gantry with minimum number of quadrupoles

    International Nuclear Information System (INIS)

    Pavlovic, Marius; Griesmayer, Erich; Seemann, Rolf

    2005-01-01

    A beam-transport study of an isocentric gantry for ion therapy is presented. The gantry is designed with the number of quadrupoles down to the theoretical minimum, which is the feature published for the first time in this paper. This feature has been achieved without compromising the ion-optical functions of the beam-transport system that is capable of handling non-symmetric beams (beams with different emittances in vertical and horizontal plane), pencil-beam scanning, double-achromatic optics and beam-size control. Ion-optical properties of the beam-transport system are described, discussed and illustrated by computer simulations performed by the TRANSPORT-code

  19. Electrons in a positive-ion beam with solenoid or quadrupole magnetic transport

    International Nuclear Information System (INIS)

    Molvik, A.W.; Kireeff Covo, M.; Cohen, R.; Coleman, J.; Sharp, W.; Bieniosek, F.; Friedman, A.; Roy, P.K.; Seidl, P.; Lund, S.M.; Faltens, A.; Vay, J.L.; Prost, L.

    2007-01-01

    The High Current Experiment (HCX) is used to study beam transport and accumulation of electrons in quadrupole magnets and the Neutralized Drift-Compression Experiment (NDCX) to study beam transport through and accumulation of electrons in magnetic solenoids. We find that both clearing and suppressor electrodes perform as intended, enabling electron cloud densities to be minimized. Then, the measured beam envelopes in both quadrupoles and solenoids agree with simulations, indicating that theoretical beam current transport limits are reliable, in the absence of electrons. At the other extreme, reversing electrode biases with the solenoid transport effectively traps electrons; or, in quadrupole magnets, grounding the suppressor electrode allows electron emission from the end wall to flood the beam, in both cases producing significant degradation in the beam

  20. Simulation studies of emittance growth in RMS mismatched beams

    International Nuclear Information System (INIS)

    Cucchetti, A.; Wangler, T.; Reiser, M.

    1991-01-01

    As shown in a separate paper, a charged-particle beam, whose rms size is not matched when injected into a transport channel or accelerator, has excess energy compared with that of a matched beam. If nonlinear space-charge forces are present and the mismatched beam transforms to a matched equilibrium state, rms-emittance growth will occur. The theory yields formulas for the possible rms-emittance growth, but not for the time it takes to achieve this growth. In this paper we present the results of systematic simulation studies for a mismatched 2-D round beam in an ideal transport channel with continuous linear focusing. Emittance growth rates obtained from the simulations for different amounts of mismatch and initial charge will be presented and the emittance growth will be compared with the theory. 6 refs., 7 figs

  1. High-Energy Beam Transport system

    International Nuclear Information System (INIS)

    Melson, K.E.; Farrell, J.A.; Liska, D.J.

    1979-01-01

    The High-Energy Beam Transport (HEBT) system for the Fusion Materials Irradiation Test (FMIT) Facility is to be installed at the Hanford Engineering Development Laboratory (HEDL) at Richland, Washington. The linear accelerator must transport a large emittance, high-current, high-power, continuous-duty deuteron beam with a large energy spread either to a lithium target or a beam stop. A periodic quadrupole and bending-magnet system provides the beam transport and focusing on target with small beam aberrations. A special rf cavity distributes the energy in the beam so that the Bragg Peak is distributed within the lithium target. Operation of the rf control system, the Energy Dispersion Cavity (EDC), and the beam transport magnets is tested on the beam stop during accelerator turn-on. Characterizing the beam will require extensions of beam diagnostic techniques and noninterceptive sensors. Provisions are being made in the facility for suspending the transport system from overhead supports using a cluster system to simplify maintenance and alignment techniques

  2. Gas-breakdown effects associated with the self-pinched transport of intense light-ion beams

    International Nuclear Information System (INIS)

    Ottinger, P.F.; Olson, C.L.; Welch, D.R.; Oliver, B.V.

    1997-01-01

    Self-pinched transport (SPT) of intense light-ion beams is being considered for delivering energy to a high-gain, high-yield inertial confinement fusion target. Proton beam SPT experiments are underway on the Gamble II generators at the Naval Research Laboratory. The physics of SPT in low-pressure gas is being analyzed with analytic theory and numerical simulations. A 1-D theory estimates the net current fraction necessary for stable transport as a function of gas density for a given beam profile. SPT simulations using the 3-D hybrid particle-in-cell (PIC) code IPROP determine the beam profile. Important to both theory and simulations is the inclusion of gas-breakdown physics. A comparison between the theory and the self-consistent simulations using IPROP is made. Additional SPT simulations have been carried out using the 2-D hybrid PIC code SOLENZ which assumes a pre-ionized plasma. This simulation model enables the investigation of long time scale beam propagation issues. A comparison between IPROP and SOLENZ will be presented. SOLENZ simulations with the Gamble I beam parameters demonstrate SPT but point to the need to study the injection conditions to improve beam confinement. Simulations examining beam-to-wall distance and injection conditions will be presented

  3. A Magnetic Transport Middle Eastern Positron Beam

    International Nuclear Information System (INIS)

    Al-Qaradawi, I.Y.; Britton, D.T.; Rajaraman, R.; Abdulmalik, D.

    2008-01-01

    A magnetically guided slow positron beam is being constructed at Qatar University and is currently being optimised for regular operation. This is the first positron beam in the Middle East, as well as being the first Arabic positron beam. Novel features in the design include a purely magnetic in-line deflector, working in the solenoid guiding field, to eliminate un-moderated positrons and block the direct line of sight to the source. The impact of this all-magnetic transport on the Larmor radius and resultant beam characteristics are studied by SIMION simulations for both ideal and real life magnetic field variations. These results are discussed in light of the coupled effect arising from electrostatic beam extraction

  4. Simulation of the CERN GTS-LHC ECR ion source extraction system with lead and argon ion beams

    CERN Document Server

    Toivanen, V; Küchler, D; Lombardi, A; Scrivens, R; Stafford-Haworth, J

    2014-01-01

    A comprehensive study of beam formation and beam transport has been initiated in order to improve the performance of the CERN heavy ion injector, Linac3. As part of this study, the ion beam extraction system of the CERN GTS-LHC 14.5 GHz Electron Cyclotron Resonance Ion Source (ECRIS) has been modelled with the ion optical code IBSimu. The simulations predict self-consistently the triangular and hollow beam structures which are often observed experimentally with ECRIS ion beams. The model is used to investigate the performance of the current extraction system and provides a basis for possible future improvements. In addition, the extraction simulation provides a more realistic representation of the initial beam properties for the beam transport simulations, which aim to identify the performance bottle necks along the Linac3 low energy beam transport. The results of beam extraction simulations with Pb and Ar ion beams from the GTS-LHC will be presented and compared with experimental observations.

  5. The IFUSP microtron accelerator beam transport line

    International Nuclear Information System (INIS)

    Rios, Paulo Beolchi

    2002-01-01

    In this work, the electron optical project of the IFUSP microtron beam transport line is presented, including the operational values for the parameters of the dipolar and quadrupolar electromagnets, as well as their location along the beam line. Analytical calculations and computer simulations were performed to obtain these results, and a programming tool was developed in order to analyze the beam parameters and to help studying racetrack microtrons. The electron optical simulations were split into two different study cases: the microtron booster, and the transfer line. In the first case, it was determined the main operational parameters of a microtron working far from its usual stability conditions. In the latter, it was done the basic design of the linking line between the booster and main (not yet built) microtrons, and between them and the experimental hall, with a total path length of approximately 32 m including large horizontal and vertical deflections with variable beam energy. (author)

  6. Parallel beam dynamics simulation of linear accelerators

    International Nuclear Information System (INIS)

    Qiang, Ji; Ryne, Robert D.

    2002-01-01

    In this paper we describe parallel particle-in-cell methods for the large scale simulation of beam dynamics in linear accelerators. These techniques have been implemented in the IMPACT (Integrated Map and Particle Accelerator Tracking) code. IMPACT is being used to study the behavior of intense charged particle beams and as a tool for the design of next-generation linear accelerators. As examples, we present applications of the code to the study of emittance exchange in high intensity beams and to the study of beam transport in a proposed accelerator for the development of accelerator-driven waste transmutation technologies

  7. Beam position measurement in transport line-1 of Indus accelerator

    International Nuclear Information System (INIS)

    Ojha, Avanish; Yadav, Surendra; Holikatti, Anil C.; Puntambekar, T.A.; Pithawa, C.K.

    2011-01-01

    In Indus Accelerator Complex at RRCAT Indore, 20 MeV electron beam is transported from injector Microtron to Booster Synchrotron through Transport Line-1 (TL-1). This beam has nominal pulse width of 500 ns with repetition rate of 1 Hz. A split electrode type beam position Indicator (BPI) is planned to be used to detect position of beam in TL-1, for which a four-channel processing electronics has been designed and developed. The circuit consists of microcontroller based four-channel peak detector circuit followed by multiplexer and ADC. The microcontroller is triggered from the timing system of microtron, which enables microcontroller to control and synchronize various parts of electronics. Microcontroller also sends the digitized data to a PC on serial link. During development, a problem of overcharging of capacitor was faced, which was resulting in false peak detection. Circuit was simulated and necessary modifications were incorporated in the circuit to solve this problem. A test setup with provision to simulate the beam signal using an antenna was used for testing the circuit in lab and a suitable Graphical User Interface (GUI) program was developed in LabVIEW. This GUI can also be used to calibrate the BPI. The prototype BPI was tested under simulated beam condition, which gave positional accuracy of ± 200 microns. (author)

  8. Research and simulation of intense pulsed beam transfer in electrostatic accelerate tube

    International Nuclear Information System (INIS)

    Li Chaolong; Shi Haiquan; Lu Jianqin

    2012-01-01

    To study intense pulsed beam transfer in electrostatic accelerate tube, the matrix method was applied to analyze the transport matrixes in electrostatic accelerate tube of non-intense pulsed beam and intense pulsed beam, and a computer code was written for the intense pulsed beam transporting in electrostatic accelerate tube. Optimization techniques were used to attain the given optical conditions and iteration procedures were adopted to compute intense pulsed beam for obtaining self-consistent solutions in this computer code. The calculations were carried out by using ACCT, TRACE-3D and TRANSPORT for different beam currents, respectively. The simulation results show that improvement of the accelerating voltage ratio can enhance focusing power of electrostatic accelerate tube, reduce beam loss and increase the transferring efficiency. (authors)

  9. Physics of gas breakdown for ion beam transport in gas

    International Nuclear Information System (INIS)

    Olson, C.L.; Poukey, J.W.; Hinshelwood, D.D.; Rose, D.V.; Hubbard, R.F.; Lampe, M.; Neri, J.M.; Ottinger, P.F.; Slinker, S.P.; Stephanakis, S.J.; Young, F.C.; Welch, D.R.

    1993-01-01

    Detailed analysis, experiments, and computer simulations are producing a new understanding of gas breakdown during intense ion beam transport in neutral gas. Charge neutralization of beam micro clumps is shown to limit the net clump potentials to a non-zero value π min , which can lead to divergence growth and axial energy spreading. At pressures approx-gt 1 Torr, plasma shielding should substantially reduce this effect Current neutralization has been studied in experiments on the GAMBLE II accelerator. The importance of fast electrons (knockons and runaways) has been established in IPROP simulations, which are in agreement with the experiments. For light ion fusion parameters with pressures approx-gt 1 Torr, very small net current fractions (much-lt 1%) appear feasible, permitting ballistic transport in gas. Self-pinched requires higher net current fractions (≥ 2%) and preliminary IPROP code results indicate that this appears achievable for small-radius intense beams in lower pressure gases (approx-gt Torr). Several self-pinched transport concepts look promising. The importance of these results for both light ion fusion and heavy ion fusion is discussed

  10. Simulation of integrated beam experiment designs

    International Nuclear Information System (INIS)

    Grote, D.P.; Sharp, W.M.

    2004-01-01

    Simulation of designs of an Integrated Beam Experiment (IBX) class accelerator have been carried out. These simulations are an important tool for validating such designs. Issues such as envelope mismatch and emittance growth can be examined in a self-consistent manner, including the details of injection, accelerator transitions, long-term transport, and longitudinal compression. The simulations are three-dimensional and time-dependent, and begin at the source. They continue up through the end of the acceleration region, at which point the data is passed on to a separate simulation of the drift compression. Results are be presented

  11. Intense-proton-beam transport through an insulator beam guide

    International Nuclear Information System (INIS)

    Hanamori, Susumu; Kawata, Shigeo; Kikuchi, Takashi; Fujita, Akira; Chiba, Yasunobu; Hikita, Taisuke; Kato, Shigeru

    1998-01-01

    In this paper we study intense-proton-beam transport through an insulator guide. In our previous papers (Jpn. J. Appl. Phys. 34 (1995) L520, Jpn. J. Appl. Phys. 35 (1996) L1127) we proposed a new system for intense-electron-beam transport using an insulator guide. In contrast to the electron beam, an intense-proton beam tends to generate a virtual anode, because of the large proton mass. The virtual anode formation at the initial stage is prevented by prefilled plasma in this system. During and after this, electrons are extracted from the plasma generated at the insulator surface by the proton beam space charge and expand over the transport area. The proton beam charge is effectively neutralized by the electrons. Consequently, the proton beam propagates efficiently through the insulator beam guide. The electron extraction is self-regulated by the net space charge of the proton beam. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Hyojae, E-mail: lkcom@ibs.re.kr; Jin, Hyunchang; Jang, Ji-Ho; Hong, In-Seok [Rare Isotope Science Project, Institute for Basic Science, Daejeon (Korea, Republic of)

    2016-02-15

    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.

  13. The role of space charge compensation for ion beam extraction and ion beam transport (invited)

    International Nuclear Information System (INIS)

    Spädtke, Peter

    2014-01-01

    Depending on the specific type of ion source, the ion beam is extracted either from an electrode surface or from a plasma. There is always an interface between the (almost) space charge compensated ion source plasma, and the extraction region in which the full space charge is influencing the ion beam itself. After extraction, the ion beam is to be transported towards an accelerating structure in most cases. For lower intensities, this transport can be done without space charge compensation. However, if space charge is not negligible, the positive charge of the ion beam will attract electrons, which will compensate the space charge, at least partially. The final degree of Space Charge Compensation (SCC) will depend on different properties, like the ratio of generation rate of secondary particles and their loss rate, or the fact whether the ion beam is pulsed or continuous. In sections of the beam line, where the ion beam is drifting, a pure electrostatic plasma will develop, whereas in magnetic elements, these space charge compensating electrons become magnetized. The transport section will provide a series of different plasma conditions with different properties. Different measurement tools to investigate the degree of space charge compensation will be described, as well as computational methods for the simulation of ion beams with partial space charge compensation

  14. Conditioner for a helically transported electron beam

    International Nuclear Information System (INIS)

    Wang, Changbiao.

    1992-05-01

    The kinetic theory is developed to investigate a conditioner for a helically transported electron beam. Linear expressions for axial velocity spread are derived. Numerical simulation is used to check the theoretical results and examine nonlinear aspects of the conditioning process. The results show that in the linear regime the action of the beam conditioner on a pulsed beam mainly depends on the phase at which the beam enters the conditioner and depends only slightly on the operating wavelength. In the nonlinear regime, however, the action of the conditioner strongly depends on the operating wavelength and only slightly upon the entrance phase. For a properly chosen operating wavelength, a little less than the electron's relativistic cyclotron wavelength, the conditioner can decrease the axial velocity spread of a pulsed beam down to less than one-third of its initial value

  15. Current neutralization in ballistic transport of light ion beams

    International Nuclear Information System (INIS)

    Hubbard, R.F.; Slinker, S.P.; Lampe, M.; Joyce, G.; Ottinger, P.

    1992-01-01

    Intense light ion beams are being considered as drivers to ignite fusion targets in the Laboratory Microfusion Facility (LMF). Ballistic transport of these beams from the diode to the target is possible only if the beam current is almost completely neutralized by plasma currents. This paper summarizes related work on relativistic electron beam and heavy ion beam propagation and describes a simple simulation model (DYNAPROP) which has been modified to treat light ion beam propagation. DYNAPROP uses an envelope equation to treat beam dynamics and uses rate equations to describe plasma and conductivity generation. The model has been applied both to the high current, 30 MeV Li +3 beams for LMF as well as low current, 1.2 MeV proton beams which are currently being studied on GAMBLE B at the Naval Research Laboratory. The predicted ratio of net currents to beam current is ∼0.1--0.2 for the GAMBLE experiment and ∼0.01 for LMF. The implications of these results for LMF and the GAMBLE experiments art discussed in some detail. The simple resistive model in DYNAPROP has well-known limitations in the 1 torr regime which arise primarily from the neglect of plasma electron transport. Alternative methods for treating the plasma response are discussed

  16. Fast damping in mismatched high intensity beam transportation

    Directory of Open Access Journals (Sweden)

    V. Variale

    2001-08-01

    Full Text Available A very fast damping of beam envelope oscillation amplitudes was recently observed in simulations of high intensity beam transport, through periodic FODO cells, in mismatched conditions [V. Variale, Nuovo Cimento Soc. Ital. Fis. 112A, 1571–1582 (1999 and T. Clauser et al., in Proceedings of the Particle Accelerator Conference, New York, 1999 (IEEE, Piscataway, NJ, 1999, p. 1779]. A Landau damping mechanism was proposed at the origin of observed effect. In this paper, to further investigate the source of this fast damping, extensive simulations have been carried out. The results presented here support the interpretation of the mechanism at the origin of the fast damping as a Landau damping effect.

  17. Low energy beam transport system developments

    Energy Technology Data Exchange (ETDEWEB)

    Dudnikov, V., E-mail: vadim@muonsinc.com [Muons, Inc., Batavia, IL 60510 (United States); Han, B.; Stockli, M.; Welton, R. [ORNL, Oak Ridge, TN 37831 (United States); Dudnikova, G. [University of Maryland, College Park, MD 3261 (United States); Institute of Computational Technologies SBRAS, Novosibirsk (Russian Federation)

    2015-04-08

    For high brightness beam production it is important to preserve the brightness in the low energy beam transport system (LEBT) used to transport and match the ion beams to the next stage of acceleration, usually an RFQ. While electrostatic focusing can be problematic for high current beam transport, reliable electrostatic LEBT operation has been demonstrated with H{sup −} beams up to 60 mA. Now, however, it is commonly accepted that an optimal LEBT for high current accelerator applications consists of focusing solenoids with space charge compensation. Two-solenoid LEBTs are successfully used for high current (>100 mA) proton beam transport. Preservation of low emittances (~0.15 π mm-mrad) requires the addition of a heavy gas (Xe, Kr), which causes ~5% of proton loss in a 1 m long LEBT. Similar Xe densities would be required to preserve low emittances of H{sup −} beams, but such gas densities cause unacceptably high H{sup −} beam losses. A short LEBT with only one short solenoid, movable for RFQ matching, can be used for reduced negative ion stripping. A strong electrostatic-focusing LEBT has been successfully adopted for transport of high current H{sup −} beams in the SNS Front End. Some modifications of such electrostatic LEBTs are expected to improve the reliable transport of intense positive and negative ion beams without greatly degrading their low emittances. We concentrate on processes that determine the beam brightness degradation and on their prevention. Proposed improvements to the SNS electrostatic LEBT are discussed.

  18. SU-E-T-58: A Novel Monte Carlo Photon Transport Simulation Scheme and Its Application in Cone Beam CT Projection Simulation

    International Nuclear Information System (INIS)

    Xu, Y; Tian, Z; Jiang, S; Jia, X; Zhou, L

    2015-01-01

    Purpose: Monte Carlo (MC) simulation is an important tool to solve radiotherapy and medical imaging problems. Low computational efficiency hinders its wide applications. Conventionally, MC is performed in a particle-by -particle fashion. The lack of control on particle trajectory is a main cause of low efficiency in some applications. Take cone beam CT (CBCT) projection simulation as an example, significant amount of computations were wasted on transporting photons that do not reach the detector. To solve this problem, we propose an innovative MC simulation scheme with a path-by-path sampling method. Methods: Consider a photon path starting at the x-ray source. After going through a set of interactions, it ends at the detector. In the proposed scheme, we sampled an entire photon path each time. Metropolis-Hasting algorithm was employed to accept/reject a sampled path based on a calculated acceptance probability, in order to maintain correct relative probabilities among different paths, which are governed by photon transport physics. We developed a package gMMC on GPU with this new scheme implemented. The performance of gMMC was tested in a sample problem of CBCT projection simulation for a homogeneous object. The results were compared to those obtained using gMCDRR, a GPU-based MC tool with the conventional particle-by-particle simulation scheme. Results: Calculated scattered photon signals in gMMC agreed with those from gMCDRR with a relative difference of 3%. It took 3.1 hr. for gMCDRR to simulate 7.8e11 photons and 246.5 sec for gMMC to simulate 1.4e10 paths. Under this setting, both results attained the same ∼2% statistical uncertainty. Hence, a speed-up factor of ∼45.3 was achieved by this new path-by-path simulation scheme, where all the computations were spent on those photons contributing to the detector signal. Conclusion: We innovatively proposed a novel path-by-path simulation scheme that enabled a significant efficiency enhancement for MC particle

  19. SU-E-T-58: A Novel Monte Carlo Photon Transport Simulation Scheme and Its Application in Cone Beam CT Projection Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Y [UT Southwestern Medical Center, Dallas, TX (United States); Southern Medical University, Guangzhou (China); Tian, Z; Jiang, S; Jia, X [UT Southwestern Medical Center, Dallas, TX (United States); Zhou, L [Southern Medical University, Guangzhou (China)

    2015-06-15

    Purpose: Monte Carlo (MC) simulation is an important tool to solve radiotherapy and medical imaging problems. Low computational efficiency hinders its wide applications. Conventionally, MC is performed in a particle-by -particle fashion. The lack of control on particle trajectory is a main cause of low efficiency in some applications. Take cone beam CT (CBCT) projection simulation as an example, significant amount of computations were wasted on transporting photons that do not reach the detector. To solve this problem, we propose an innovative MC simulation scheme with a path-by-path sampling method. Methods: Consider a photon path starting at the x-ray source. After going through a set of interactions, it ends at the detector. In the proposed scheme, we sampled an entire photon path each time. Metropolis-Hasting algorithm was employed to accept/reject a sampled path based on a calculated acceptance probability, in order to maintain correct relative probabilities among different paths, which are governed by photon transport physics. We developed a package gMMC on GPU with this new scheme implemented. The performance of gMMC was tested in a sample problem of CBCT projection simulation for a homogeneous object. The results were compared to those obtained using gMCDRR, a GPU-based MC tool with the conventional particle-by-particle simulation scheme. Results: Calculated scattered photon signals in gMMC agreed with those from gMCDRR with a relative difference of 3%. It took 3.1 hr. for gMCDRR to simulate 7.8e11 photons and 246.5 sec for gMMC to simulate 1.4e10 paths. Under this setting, both results attained the same ∼2% statistical uncertainty. Hence, a speed-up factor of ∼45.3 was achieved by this new path-by-path simulation scheme, where all the computations were spent on those photons contributing to the detector signal. Conclusion: We innovatively proposed a novel path-by-path simulation scheme that enabled a significant efficiency enhancement for MC particle

  20. Beam control and matching for the transport of intense beams

    International Nuclear Information System (INIS)

    Li, H.; Bernal, S.; Godlove, T.; Huo, Y.; Kishek, R.A.; Haber, I.; Quinn, B.; Walter, M.; Zou, Y.; Reiser, M.; O'Shea, P.G.

    2005-01-01

    The transport of intense beams for heavy-ion inertial fusion demands tight control of beam characteristics from the source to the target. The University of Maryland Electron Ring (UMER), which uses a low-energy (10 keV), high-current electron beam to model the transport physics of a future recirculator driver, employs real-time beam characterization and control in order to optimize beam quality throughout the strong focusing lattice. We describe the main components and operation of the diagnostics/control system in UMER. It employs phosphor screens, real-time image analysis, quadrupole scans and electronic skew correctors. The procedure is not only indispensable for optimum transport over a long distance, but also provides important insights into the beam physics involved. We discuss control/optimization issues related to beam steering, quadrupole rotation errors and rms envelope matching

  1. Low energy beam transport for HIDIF

    International Nuclear Information System (INIS)

    Meusel, O.; Pozimski, J.; Jakob, A.; Lakatos, A.

    2001-01-01

    Low energy beam transport (LEBT) for a heavy ion inertial fusion (HIDIF, I. Hofmann and G. Plass, Report of the European Study Group on Heavy Ion Driven Inertial Fusion for the Period 1995-1998) facility suffers from high space charge forces and high ion mass. Space charge compensation reduces the necessary focusing force of the lenses and the radius of the beam in the LEBT, and therefrom the emittance growth due to aberrations and self fields is reduced. Gabor lenses (D. Gabor, Nature 160 (1947)) providing a stable space charge cloud for focusing and combine strong cylinder symmetric focusing with partly space charge compensation and low emittance growth. A high tolerance against source noise and current fluctuations and reduced investment costs could be other possible advantages. The proof of principle has already been demonstrated (J.A. Palkovic, Measurements on a Gabor lens for Neutralizing and Focusing a 30 keV Proton beam, University of Wisconsin, Madison, 1989; J. Pozimski, P. Gross, R. Doelling and T. Weis, First experimental studies of a Gabor plasma-lens in Frankfurt, Proceedings of the 3rd EPAC Conference, Berlin, 1992). To broaden the experiences and to investigate the realisation of a LEBT concept for the HIDIF injector an experimental program using two Gabor lenses for independent variation of beam radius and envelope angel at RFQ injection was started. Therefrom the first experimental results using a double Gabor lens (DGPL) LEBT system for transporting an high perveance Xe + beam are presented and the results of numerical simulations are shown

  2. Low energy beam transport for HIDIF

    Energy Technology Data Exchange (ETDEWEB)

    Meusel, O. E-mail: o.meusel@iap.uni-frankfurt.de; Pozimski, J.; Jakob, A.; Lakatos, A

    2001-05-21

    Low energy beam transport (LEBT) for a heavy ion inertial fusion (HIDIF, I. Hofmann and G. Plass, Report of the European Study Group on Heavy Ion Driven Inertial Fusion for the Period 1995-1998) facility suffers from high space charge forces and high ion mass. Space charge compensation reduces the necessary focusing force of the lenses and the radius of the beam in the LEBT, and therefrom the emittance growth due to aberrations and self fields is reduced. Gabor lenses (D. Gabor, Nature 160 (1947)) providing a stable space charge cloud for focusing and combine strong cylinder symmetric focusing with partly space charge compensation and low emittance growth. A high tolerance against source noise and current fluctuations and reduced investment costs could be other possible advantages. The proof of principle has already been demonstrated (J.A. Palkovic, Measurements on a Gabor lens for Neutralizing and Focusing a 30 keV Proton beam, University of Wisconsin, Madison, 1989; J. Pozimski, P. Gross, R. Doelling and T. Weis, First experimental studies of a Gabor plasma-lens in Frankfurt, Proceedings of the 3rd EPAC Conference, Berlin, 1992). To broaden the experiences and to investigate the realisation of a LEBT concept for the HIDIF injector an experimental program using two Gabor lenses for independent variation of beam radius and envelope angel at RFQ injection was started. Therefrom the first experimental results using a double Gabor lens (DGPL) LEBT system for transporting an high perveance Xe{sup +} beam are presented and the results of numerical simulations are shown.

  3. Predictive Simulations of ITER Including Neutral Beam Driven Toroidal Rotation

    International Nuclear Information System (INIS)

    Halpern, Federico D.; Kritz, Arnold H.; Bateman, G.; Pankin, Alexei Y.; Budny, Robert V.; McCune, Douglas C.

    2008-01-01

    Predictive simulations of ITER [R. Aymar et al., Plasma Phys. Control. Fusion 44, 519 2002] discharges are carried out for the 15 MA high confinement mode (H-mode) scenario using PTRANSP, the predictive version of the TRANSP code. The thermal and toroidal momentum transport equations are evolved using turbulent and neoclassical transport models. A predictive model is used to compute the temperature and width of the H-mode pedestal. The ITER simulations are carried out for neutral beam injection (NBI) heated plasmas, for ion cyclotron resonant frequency (ICRF) heated plasmas, and for plasmas heated with a mix of NBI and ICRF. It is shown that neutral beam injection drives toroidal rotation that improves the confinement and fusion power production in ITER. The scaling of fusion power with respect to the input power and to the pedestal temperature is studied. It is observed that, in simulations carried out using the momentum transport diffusivity computed using the GLF23 model [R.Waltz et al., Phys. Plasmas 4, 2482 (1997)], the fusion power increases with increasing injected beam power and central rotation frequency. It is found that the ITER target fusion power of 500 MW is produced with 20 MW of NBI power when the pedesta temperature is 3.5 keV. 2008 American Institute of Physics. [DOI: 10.1063/1.2931037

  4. Theory and Simulation of the Physics of Space Charge Dominated Beams

    International Nuclear Information System (INIS)

    Haber, Irving

    2002-01-01

    This report describes modeling of intense electron and ion beams in the space charge dominated regime. Space charge collective modes play an important role in the transport of intense beams over long distances. These modes were first observed in particle-in-cell simulations. The work presented here is closely tied to the University of Maryland Electron Ring (UMER) experiment and has application to accelerators for heavy ion beam fusion

  5. Implementation of depolarization due to beam-beam effects in the beam-beam interaction simulation tool GUINEA-PIG++

    Science.gov (United States)

    Rimbault, C.; Le Meur, G.; Blampuy, F.; Bambade, P.; Schulte, D.

    2009-12-01

    Depolarization is a new feature in the beam-beam simulation tool GUINEA-PIG++ (GP++). The results of this simulation are studied and compared with another beam-beam simulation tool, CAIN, considering different beam parameters for the International Linear Collider (ILC) with a centre-of-mass energy of 500 GeV.

  6. Comparison of beam simulations with measurements for a 1.25-MeV, CW RFQ

    International Nuclear Information System (INIS)

    Smith, H.V. Jr.; Bolme, G.O.; Sherman, J.D.; Stevens, R.R. Jr.; Young, L.M.; Zaugg, T.J.

    1998-01-01

    The Low-Energy Demonstration Accelerator (LEDA) injector is tested using the Chalk River Injector Test Stand (CRITS) radio-frequency quadrupole (RFQ) as a diagnostic instrument. Fifty-keV, dc proton beams are injected into the 1.25-MeV, CW RFQ and transported to a beamstop. Computer-simulation-code predictions of the expected beam performance are compared with the measured beam currents and beam profiles. Good agreement is obtained between the measurements and the simulations at the 75-mA design RFQ output current

  7. LATTICE/hor ellipsis/a beam transport program

    International Nuclear Information System (INIS)

    Staples, J.

    1987-06-01

    LATTICE is a computer program that calculates the first order characteristics of synchrotrons and beam transport systems. The program uses matrix algebra to calculate the propagation of the betatron (Twiss) parameters along a beam line. The program draws on ideas from several older programs, notably Transport and Synch, adds many new ones and incorporates them into an interactive, user-friendly program. LATTICE will calculate the matched functions of a synchrotron lattice and display them in a number of ways, including a high resolution Tektronix graphics display. An optimizer is included to adjust selected element parameters so the beam meets a set of constraints. LATTICE is a first order program, but the effect of sextupoles on the chromaticity of a synchrotron lattice is included, and the optimizer will set the sextupole strengths for zero chromaticity. The program will also calculate the characteristics of beam transport systems. In this mode, the beam parameters, defined at the start of the transport line, are propagated through to the end. LATTICE has two distinct modes: the lattice mode which finds the matched functions of a synchrotron, and the transport mode which propagates a predefined beam through a beam line. However, each mode can be used for either type of problem: the transport mode may be used to calculate an insertion for a synchrotron lattice, and the lattice mode may be used to calculate the characteristics of a long periodic beam transport system

  8. Simulation of Beam-Beam Background at CLIC

    CERN Document Server

    Sailer, Andre

    2010-01-01

    The dense beams used at CLIC to achieve a high luminosity will cause a large amount of background particles through beam-beam interactions. Generator level studies with GuineaPig and full detector simulation studies with an ILD based CLIC detector have been performed to evaluate the amount of beam-beam background hitting the vertex detector.

  9. Simulation of Beam-Beam Background at CLIC

    CERN Document Server

    Sailer, A

    2010-01-01

    The dense beams used at CLIC to achieve a high luminosity will cause a large amount of background particles through beam-beam interactions. Generator level studies with GUINEAPIG and full detector simulation studies with an ILD based CLIC detector have been performed to evaluate the amount of beam-beam back- ground hitting the vertex detector.

  10. Nonlinear delta f Simulations of Collective Effects in Intense Charged Particle Beams

    CERN Document Server

    Hong Qi

    2003-01-01

    A nonlinear delta(f) particle simulation method based on the Vlasov-Maxwell equations has been recently developed to study collective processes in high-intensity beams, where space-charge and magnetic self-field effects play a critical role in determining the nonlinear beam dynamics. Implemented in the Beam Equilibrium, Stability and Transport (BEST) code [H. Qin, R.C. Davidson, and W.W. Lee, Physical Review -- Special Topics on Accelerator and Beams 3 (2000) 084401; 3 (2000) 109901.], the nonlinear delta(f) method provides a low-noise and self-consistent tool for simulating collective interactions and nonlinear dynamics of high-intensity beams in modern and next-generation accelerators and storage rings, such as the Spallation Neutron Source and heavy ion fusion drivers. A wide range of linear eigenmodes of high-intensity charged-particle beams can be systematically studied using the BEST code. Simulation results for the electron-proton two-stream instability in the Proton Storage Ring experiment [R. Macek, ...

  11. Improved single particle potential for transport model simulations of nuclear reactions induced by rare isotope beams

    International Nuclear Information System (INIS)

    Xu Chang; Li Baoan

    2010-01-01

    Taking into account more accurately the isospin dependence of nucleon-nucleon interactions in the in-medium many-body force term of the Gogny effective interaction, new expressions for the single-nucleon potential and the symmetry energy are derived. Effects of both the spin (isospin) and the density dependence of nuclear effective interactions on the symmetry potential and the symmetry energy are examined. It is shown that they both play a crucial role in determining the symmetry potential and the symmetry energy at suprasaturation densities. The improved single-nucleon potential will be useful for more accurate simulation of nuclear reactions induced by rare-isotope beams within transport models.

  12. COMPARISON OF RF CAVITY TRANSPORT MODELS FOR BBU SIMULATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Ilkyoung Shin,Byung Yunn,Todd Satogata,Shahid Ahmed

    2011-03-01

    The transverse focusing effect in RF cavities plays a considerable role in beam dynamics for low-energy beamline sections and can contribute to beam breakup (BBU) instability. The purpose of this analysis is to examine RF cavity models in simulation codes which will be used for BBU experiments at Jefferson Lab and improve BBU simulation results. We review two RF cavity models in the simulation codes elegant and TDBBU (a BBU simulation code developed at Jefferson Lab). elegant can include the Rosenzweig-Serafini (R-S) model for the RF focusing effect. Whereas TDBBU uses a model from the code TRANSPORT which considers the adiabatic damping effect, but not the RF focusing effect. Quantitative comparisons are discussed for the CEBAF beamline. We also compare the R-S model with the results from numerical simulations for a CEBAF-type 5-cell superconducting cavity to validate the use of the R-S model as an improved low-energy RF cavity transport model in TDBBU. We have implemented the R-S model in TDBBU. It will improve BBU simulation results to be more matched with analytic calculations and experimental results.

  13. Comparison Of RF Cavity Transport Models For BBU Simulations

    International Nuclear Information System (INIS)

    Shin, Ilkyoung; Yunn, Byung; Satogata, Todd; Ahmed, Shahid

    2011-01-01

    The transverse focusing effect in RF cavities plays a considerable role in beam dynamics for low-energy beamline sections and can contribute to beam breakup (BBU) instability. The purpose of this analysis is to examine RF cavity models in simulation codes which will be used for BBU experiments at Jefferson Lab and improve BBU simulation results. We review two RF cavity models in the simulation codes elegant and TDBBU (a BBU simulation code developed at Jefferson Lab). elegant can include the Rosenzweig-Serafini (R-S) model for the RF focusing effect. Whereas TDBBU uses a model from the code TRANSPORT which considers the adiabatic damping effect, but not the RF focusing effect. Quantitative comparisons are discussed for the CEBAF beamline. We also compare the R-S model with the results from numerical simulations for a CEBAF-type 5-cell superconducting cavity to validate the use of the R-S model as an improved low-energy RF cavity transport model in TDBBU. We have implemented the R-S model in TDBBU. It will improve BBU simulation results to be more matched with analytic calculations and experimental results.

  14. Source-to-target simulation of simultaneous longitudinal and transverse focusing of heavy ion beams

    Directory of Open Access Journals (Sweden)

    D. R. Welch

    2008-06-01

    Full Text Available Longitudinal bunching factors in excess of 70 of a 300-keV, 27-mA K^{+} ion beam have been demonstrated in the neutralized drift compression experiment [P. K. Roy et al., Phys. Rev. Lett. 95, 234801 (2005PRLTAO0031-900710.1103/PhysRevLett.95.234801] in rough agreement with particle-in-cell source-to-target simulations. A key aspect of these experiments is that a preformed plasma provides charge neutralization of the ion beam in the last one meter drift region where the beam perveance becomes large. The simulations utilize the measured ion source temperature, diode voltage, and induction-bunching-module voltage waveforms in order to determine the initial beam longitudinal phase space which is critical to accurate modeling of the longitudinal compression. To enable simultaneous longitudinal and transverse compression, numerical simulations were used in the design of the solenoidal focusing system that compensated for the impact of the applied velocity tilt on the transverse phase space of the beam. Complete source-to-target simulations, that include detailed modeling of the diode, magnetic transport, induction bunching module, and plasma neutralized transport, were critical to understanding the interplay between the various accelerator components in the experiment. Here, we compare simulation results with the experiment and discuss the contributions to longitudinal and transverse emittance that limit the final compression.

  15. Focused transport of intense charged particle beams. Final technical report FY/93

    International Nuclear Information System (INIS)

    1997-01-01

    Many recent developments in accelerator technology have increased the need for a better understanding of the physics of intense-beam transport. Of particular interest to the work described here is the appearance, as beam intensities are increased, of a class of nonlinear phenomena which involve the collective interaction of the beam particles. Beam intensity, used as a measure of the importance of space-charge collective behavior, depends on the ratio of current to emittance. The nonlinear beam dynamics, and any resulting emittance growth, which are characteristic of the intense-beam regime, can therefore occur even at low currents in any accelerator system with sufficiently high intensity, especially in the low beta section. Furthermore, since emittance of a beam is difficult to reduce, the ultimate achievement of necessary beam luminosities requires the consideration of possible causes of longitudinal and transverse emittance growth at every stage of the beam lifetime. The research program described here has addressed the fundamental physics which comes into play during the transport, acceleration and focusing of intense beams. Because of the long term and ongoing nature of the research program discussed here, this report is divided into two sections. The first section constitutes a long term revue of the accomplishments which have resulted from the research effort reported, especially in pioneering the use of particle-in-cell (PIC) computer simulation techniques for simulation of the dynamics of space-charge-dominated beams in particle accelerators. The following section emphasizes, in more detail, the accomplishments of the FY 92/93 period immediately prior to the termination of this particular avenue of support. 41 refs

  16. Third-order TRANSPORT: A computer program for designing charged particle beam transport systems

    International Nuclear Information System (INIS)

    Carey, D.C.; Brown, K.L.; Rothacker, F.

    1995-05-01

    TRANSPORT has been in existence in various evolutionary versions since 1963. The present version of TRANSPORT is a first-, second-, and third-order matrix multiplication computer program intended for the design of static-magnetic beam transport systems. This report discusses the following topics on TRANSPORT: Mathematical formulation of TRANSPORT; input format for TRANSPORT; summaries of TRANSPORT elements; preliminary specifications; description of the beam; physical elements; other transformations; assembling beam lines; operations; variation of parameters for fitting; and available constraints -- the FIT command

  17. Simulation and experimental study on transportation of dual-beam guided by confining magnetic-field

    International Nuclear Information System (INIS)

    Bai Xianchen; Zhang Jiande; Yang Jianhua

    2008-01-01

    Using external longitudinal magnetic-field to guide dual-beam out of the dual-shift tubes is a key step for the practicality of synchronizing dual-beam produced by a single accelerator. On the basis of the simulation of the confining magnetic-field for the solid dual-beam, the experiment of magnetic-field guiding annular dual-beam was presented. When the diode voltage was 380 kV, dual-beam currents of 5.10 kA and 4.92 kA were obtained. The experimental results indicate that the designed magnetic-field system could confine the annular dual-beam effectively, and the critical confining magnetic-field is about 0.5 T. (authors)

  18. Beam transport design for a recirculating-linac FEL driver

    International Nuclear Information System (INIS)

    Neuffer, D.; Douglas, D.; Li, Z.; Cornacchia, M.; Garren, A.

    1996-01-01

    The beam transport system for the CEBAF Industrial FEL includes a two-pass transport of the beam with acceleration from injector to wiggler, followed by energy recovery transport from wiggler to dump. From that context, the authors discuss the general problem of multi-pass energy-recovery beam transport for FELs. Tunable, nearly-isochronous, large-momentum-acceptance transport systems are required. The entire transport must preserve beam quality, particularly in the acceleration transport to the wiggler, and have low losses throughout the entire system. Various possible designs are presented, and results of dynamic analyses are discussed

  19. Dynamics of laser-driven proton beam focusing and transport into solid density matter

    Science.gov (United States)

    Kim, J.; McGuffey, C.; Beg, F.; Wei, M.; Mariscal, D.; Chen, S.; Fuchs, J.

    2016-10-01

    Isochoric heating and local energy deposition capabilities make intense proton beams appealing for studying high energy density physics and the Fast Ignition of inertial confinement fusion. To study proton beam focusing that results in high beam density, experiments have been conducted using different target geometries irradiated by a kilojoule, 10 ps pulse of the OMEGA EP laser. The beam focus was measured by imaging beam-induced Cu K-alpha emission on a Cu foil that was positioned at a fixed distance. Compared to a free target, structured targets having shapes of wedge and cone show a brighter and narrower K-alpha radiation emission spot on a Cu foil indicating higher beam focusability. Experimentally observed images with proton radiography demonstrate the existence of transverse fields on the structures. Full-scale simulations including the contribution of a long pulse duration of the laser confirm that such fields can be caused by hot electrons moving through the structures. The simulated fields are strong enough to reflect the diverging main proton beam and pinch a transverse probe beam. Detailed simulation results including the beam focusing and transport of the focused intense proton beam in Cu foil will be presented. This work was supported by the National Laser User Facility Program through Award DE-NA0002034.

  20. Simulation of the beam halo from the beam-beam interaction in LEP

    International Nuclear Information System (INIS)

    Chen, T.; Irwin, J.; Siemann, R.

    1994-02-01

    The luminosity lifetimes of e + e - colliders are often dominated by the halo produced by the beam-beam interaction. They have developed a simulation technique to model this halo using the flux across boundaries in amplitude space to decrease the CPU time by a factor of one-hundred or more over 'brute force' tracking. It allows simulation of density distributions and halos corresponding to realistic lifetimes. Reference 1 shows the agreement with brute force tracking in a number of cases and the importance of beam-beam resonances in determining the density distribution of large amplitudes. this research is now directed towards comparisons with operating colliders and studies of the combined effects of lattice and beam-beam nonlinearities. LEP offers an ideal opportunity for both, and in this paper they are presenting the first results of LEP simulations

  1. IPROP simulations of the GAMBLE II proton transport experiment

    International Nuclear Information System (INIS)

    Welch, D.R.

    1993-01-01

    The author has simulated the proton transport of the 6-kA, 1-MV GAMBLE II experiment using a modified version of the IPROP particle-in-cell code. IPROP now uses a hybrid model in which plasma electrons are divided into high-energy macro particle and thermal-fluid components. This model includes open-quotes knock-onclose quotes bound-electron collision and runaway sources for high-energy electrons. Using IPROP, the authors has calculated net currents in reasonable agreement with the experiment ranging from 5-11% of the total current in pressures from 0.25-4 torr helium. In the simulations, the pinch current sample by the 1.5-cm beam was 2-3 times larger than the net current at 4 cm radius. The attenuation of net current at larger radii was the result of a highly-conductive energetic component of plasma electrons surrounding the beam. Having benchmarked IPROP against experiment, the author has examined higher-current ion beams with respect to possible transport for inertial confinement fusion

  2. Space charge compensation in the Linac4 low energy beam transport line with negative hydrogen ions

    Energy Technology Data Exchange (ETDEWEB)

    Valerio-Lizarraga, Cristhian A., E-mail: cristhian.alfonso.valerio.lizarraga@cern.ch [CERN, Geneva (Switzerland); Departamento de Investigación en Física, Universidad de Sonora, Hermosillo (Mexico); Lallement, Jean-Baptiste; Lettry, Jacques; Scrivens, Richard [CERN, Geneva (Switzerland); Leon-Monzon, Ildefonso [Facultad de Ciencias Fisico-Matematicas, Universidad Autónoma de Sinaloa, Culiacan (Mexico); Midttun, Øystein [CERN, Geneva (Switzerland); University of Oslo, Oslo (Norway)

    2014-02-15

    The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Transport using the package IBSimu [T. Kalvas et al., Rev. Sci. Instrum. 81, 02B703 (2010)], which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H{sup −} beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree.

  3. Transport simulations TFTR: Theoretically-based transport models and current scaling

    International Nuclear Information System (INIS)

    Redi, M.H.; Cummings, J.C.; Bush, C.E.; Fredrickson, E.; Grek, B.; Hahm, T.S.; Hill, K.W.; Johnson, D.W.; Mansfield, D.K.; Park, H.; Scott, S.D.; Stratton, B.C.; Synakowski, E.J.; Tang, W.M.; Taylor, G.

    1991-12-01

    In order to study the microscopic physics underlying observed L-mode current scaling, 1-1/2-d BALDUR has been used to simulate density and temperature profiles for high and low current, neutral beam heated discharges on TFTR with several semi-empirical, theoretically-based models previously compared for TFTR, including several versions of trapped electron drift wave driven transport. Experiments at TFTR, JET and D3-D show that I p scaling of τ E does not arise from edge modes as previously thought, and is most likely to arise from nonlocal processes or from the I p -dependence of local plasma core transport. Consistent with this, it is found that strong current scaling does not arise from any of several edge models of resistive ballooning. Simulations with the profile consistent drift wave model and with a new model for toroidal collisionless trapped electron mode core transport in a multimode formalism, lead to strong current scaling of τ E for the L-mode cases on TFTR. None of the theoretically-based models succeeded in simulating the measured temperature and density profiles for both high and low current experiments

  4. IMPACT simulation and the SNS linac beam

    International Nuclear Information System (INIS)

    Zhang, Y.; Qiang, J.

    2008-01-01

    Multi-particle tracking simulations for the SNS linac beam dynamics studies are performed with the IMPACT code. Beam measurement results are compared with the computer simulations, including beam longitudinal halo and beam losses in the superconducting linac, transverse beam Courant-Snyder parameters and the longitudinal beam emittance in the linac. In most cases, the simulations show good agreement with the measured results

  5. TRANSPORT: a computer program for designing charged particle beam transport systems

    International Nuclear Information System (INIS)

    Brown, K.L.; Rothacker, F.; Carey, D.C.; Iselin, C.

    1977-05-01

    TRANSPORT is a first- and second-order matrix multiplication computer program intended for the design of static-magnetic beam transport systems. It has been in existence in various evolutionary versions since 1963. The present version, described in the manual given, includes both first- and second-order fitting capabilities. TRANSPORT will step through the beam line, element by element, calculating the properties of the beam or other quantities, described below, where requested. Therefore one of the first elements is a specification of the phase space region occupied by the beam entering the system. Magnets and intervening spaces and other elements then follow in the sequence in which they occur in the beam line. Specifications of calculations to be done or of configurations other than normal are placed in the same sequence, at the point where their effect is to be made

  6. Development of a relativistic Particle In Cell code PARTDYN for linear accelerator beam transport

    Energy Technology Data Exchange (ETDEWEB)

    Phadte, D., E-mail: deepraj@rrcat.gov.in [LPD, Raja Ramanna Centre for Advanced Technology, Indore 452013 (India); Patidar, C.B.; Pal, M.K. [MAASD, Raja Ramanna Centre for Advanced Technology, Indore (India)

    2017-04-11

    A relativistic Particle In Cell (PIC) code PARTDYN is developed for the beam dynamics simulation of z-continuous and bunched beams. The code is implemented in MATLAB using its MEX functionality which allows both ease of development as well higher performance similar to a compiled language like C. The beam dynamics calculations carried out by the code are compared with analytical results and with other well developed codes like PARMELA and BEAMPATH. The effect of finite number of simulation particles on the emittance growth of intense beams has been studied. Corrections to the RF cavity field expressions were incorporated in the code so that the fields could be calculated correctly. The deviations of the beam dynamics results between PARTDYN and BEAMPATH for a cavity driven in zero-mode have been discussed. The beam dynamics studies of the Low Energy Beam Transport (LEBT) using PARTDYN have been presented.

  7. Particle-in-Cell Code BEAMPATH for Beam Dynamics Simulations in Linear Accelerators and Beamlines

    International Nuclear Information System (INIS)

    Batygin, Y.

    2004-01-01

    A code library BEAMPATH for 2 - dimensional and 3 - dimensional space charge dominated beam dynamics study in linear particle accelerators and beam transport lines is developed. The program is used for particle-in-cell simulation of axial-symmetric, quadrupole-symmetric and z-uniform beams in a channel containing RF gaps, radio-frequency quadrupoles, multipole lenses, solenoids and bending magnets. The programming method includes hierarchical program design using program-independent modules and a flexible combination of modules to provide the most effective version of the structure for every specific case of simulation. Numerical techniques as well as the results of beam dynamics studies are presented

  8. Particle-in-Cell Code BEAMPATH for Beam Dynamics Simulations in Linear Accelerators and Beamlines

    Energy Technology Data Exchange (ETDEWEB)

    Batygin, Y.

    2004-10-28

    A code library BEAMPATH for 2 - dimensional and 3 - dimensional space charge dominated beam dynamics study in linear particle accelerators and beam transport lines is developed. The program is used for particle-in-cell simulation of axial-symmetric, quadrupole-symmetric and z-uniform beams in a channel containing RF gaps, radio-frequency quadrupoles, multipole lenses, solenoids and bending magnets. The programming method includes hierarchical program design using program-independent modules and a flexible combination of modules to provide the most effective version of the structure for every specific case of simulation. Numerical techniques as well as the results of beam dynamics studies are presented.

  9. Design of a high-current low-energy beam transport line for an intense D-T/D-D neutron generator

    International Nuclear Information System (INIS)

    Lu, Xiaolong; Wang, Junrun; Zhang, Yu; Li, Jianyi; Xia, Li; Zhang, Jie; Ding, Yanyan; Jiang, Bing; Huang, Zhiwu; Ma, Zhanwen; Wei, Zheng; Qian, Xiangping; Xu, Dapeng; Lan, Changlin; Yao, Zeen

    2016-01-01

    An intense D-T/D-D neutron generator is currently being developed at the Lanzhou University. The Cockcroft–Walton accelerator, as a part of the neutron generator, will be used to accelerate and transport the high-current low-energy beam from the duoplasmatron ion source to the rotating target. The design of a high-current low-energy beam transport (LEBT) line and the dynamics simulations of the mixed beam were carried out using the TRACK code. The results illustrate that the designed beam line facilitates smooth transportation of a deuteron beam of 40 mA, and the number of undesired ions can be reduced effectively using two apertures.

  10. Computer codes for automatic tuning of the beam transport at the UNILAC

    International Nuclear Information System (INIS)

    Dahl, L.; Ehrich, A.

    1984-01-01

    For application in routine operation fully automatic computer controlled algorithms are developed for tuning of beam transport elements at the Unilac. Computations, based on emittance measurements, simulate the beam behaviour and evaluate quadrupole settings, in order to produce defined beam properties at specified positions along the accelerator. The interactive program is controlled using a graphic display on which the beam emittances and envelopes are plotted. To align the beam onto the ion-optical axis of the accelerator two automatic computer controlled procedures have been developed. The misalignment of the beam is determined by variation of quadrupole or steering magnet settings with simultaneous measurement of the beam distribution on profile grids. According to the result a pair of steering magnet settings are adjusted to bend the beam on the axis. The effects of computer controlled tuning on beam quality and operation are reported

  11. Beam transport

    International Nuclear Information System (INIS)

    1988-01-01

    Considerable experience has now been gained with the various beam transport lines, and a number of minor changes have been made to improve the ease of operation. These include: replacement of certain little-used slits by profile monitors (harps or scanners); relocation of steering magnets, closer to diagnostic harps or profile scanners; installation of a scanner inside the isocentric neutron therapy system; and conversion of a 2-doublet quadrupole telescope (on the neutron therapy beamline) to a 2-triplet telescope. The beam-swinger project has been delayed by very late delivery of the magnet iron to the manufacturer, but is now progressing smoothly. The K=600 spectrometer magnets have now been delivered and are being assembled for field mapping. The x,y-table with its associated mapping equipment is complete, together with the driver software. One of the experimental areas has been dedicated to the production of collimated neutron beams and has been equipped with a bending magnet and beam dump, together with steel collimators fixed at 4 degrees intervals from 0 degrees to 16 degrees. Changes to the target cooling and shielding system for isotope production have led to a request for much smaller beam spot sizes on target, and preparations have been made for rearrangement of the isotope beamline to permit installation of quadrupole triplets on the three beamlines after the switching magnet. A practical system of quadrupoles for matching beam properties to the spectrometer has been designed. 6 figs

  12. High current beam transport experiments at GSI

    International Nuclear Information System (INIS)

    Klabunde, J.; Schonlein, A.; Spadtke, P.

    1985-01-01

    The status of the high current ion beam transport experiment is reported. 190 keV Ar 1+ ions were injected into six periods of a magnetic quadrupole channel. Since the pulse length is > 0.5 ms partial space charge neutralization occurs. In our experiments, the behavior of unneutralized and partially space charge compensated beams is compared. With an unneutralized beam, emittance growth has been measured for high intensities even in case of the zero-current phase advance sigma 0 0 . This initial emittance growth at high tune depression we attribute to the homogenization effect of the space charge density. An analytical formula based on this assumption describes the emittance growth very well. Furthermore the predicted envelope instabilities for sigma 0 > 90 0 were observed even after 6 periods. In agreement with the theory, unstable beam transport was also experimentally found if a beam with different emittances in the two transverse phase planes was injected into the transport channel. Although the space charge force is reduced for a partially neutralized beam a deterioration of the beam quality was measured in a certain range of beam parameters. Only in the range where an unneutralized beam shows the initial emittance growth, the partial neutralization reduces this effect, otherwise the partially neutralized beam is more unstable

  13. Micro computer aided beam transport for the SF cyclotron

    International Nuclear Information System (INIS)

    Honma, Toshihiro; Yamazaki, Tsutomu.

    1984-01-01

    An improvement of the beam transport system for the SF cyclotron is described. The system was designed to handle on-line alignment of the beam extracted from the SF cyclotron onto the optical axis of the transport line. It also enables to measure the beam emittance. The measurement of the emittance parameters is in particular necessary to calculate the beam optics. The calculation has been modified to become easy to handle. With the help of the computer-aided on-line beam profile measurement system, the operation of the beam transport system is very subservient to shorten the beam-tuning time and to improve the beam-transmission efficiency and the quality. (author)

  14. The programme library for numerical simulation of charged particle dynamics in transportation lines

    International Nuclear Information System (INIS)

    Aleksandrov, V.S.; Shevtsov, V.F.; Shirkov, G.D.; Batygin, Yu.K.

    1998-01-01

    The description of a PC codes library to simulate the beam transportation of charged particles is presented. The codes are realized on IBM PC in Visual Basic common interface. It is destined for the simulation and optimization of beam dynamics and based on the successive and consistent use of two methods: the momentum method of distribution functions (RMS technique) and the particle-particle method (PP-Method). The library allows to calculate the RMS parameters of electron and ion beams, passing through a set of quadrupoles, solenoids, bends, accelerating sections. The RMS code is a fast code very suitable for the first test, design and optimization of the beam line parameters. The PP code requires more time for execution but provides a high accuracy of simulation taking into account the space charge effects, aberrations and beam losses. One of the main advantages of PP code presented here is an ability to simulate a real multicomponent beam of different masses and charged states of ions from ion sources

  15. Simulation study of the beam-beam interaction at SPEAR

    International Nuclear Information System (INIS)

    Tennyson, J.

    1980-01-01

    A two dimensional simulation study of the beam-beam interaction at SPEAR indicates that quantum fluctuations affecting the horizontal betatron oscillation play a critical role in the vertical beam blowup

  16. Simulation of Chamber Transport for Heavy-Ion-Fusion Drivers

    International Nuclear Information System (INIS)

    Sharp, W.M.; Callahan, D.A.; Tabak, M.; Yu, S.S.; Peterson, P.F.; Rose, D.V.; Welch, D.R.

    2003-01-01

    The heavy-ion fusion (HIF) community recently developed a power-plant design that meets the various requirements of accelerators, final focus, chamber transport, and targets. The point design is intended to minimize physics risk and is certainly not optimal for the cost of electricity. Recent chamber-transport simulations, however, indicate that changes in the beam ion species, the convergence angle, and the emittance might allow more-economical designs

  17. Chamber-transport simulation results for heavy-ion fusion drivers

    International Nuclear Information System (INIS)

    Sharp, W M; Callahan, D A; Tabak, M; Yu, S S; Peterson, P F; Rose, D V; Welch, D R

    2004-01-01

    The heavy-ion fusion (HIF) community recently developed a power-plant design that meets the various requirements of accelerators, final focus, chamber transport, and targets. The point design is intended to minimize physics risk and is certainly not optimal for the cost of electricity. Recent chamber-transport simulations, however, indicate that changes in the beam ion species, the convergence angle, and the emittance might allow more-economical designs

  18. SIMULATION OF CHAMBER TRANSPORT FOR HEAVY-ION FUSION DRIVERS

    International Nuclear Information System (INIS)

    Sharp, W M; Callahan, D A; Tabak, M; Yu, S S; Peterson, P F; Rose, D V; Welch, D R

    2004-01-01

    The heavy-ion fusion (HIF) community recently developed a power-plant design that meets the various requirements of accelerators, final focus, chamber transport, and targets. The point design is intended to minimize physics risk and is certainly not optimal for the cost of electricity. Recent chamber-transport simulations, however, indicate that changes in the beam ion species, the convergence angle, and the emittance might allow more-economical designs

  19. Simulation of long-distance beam propagation in the Paul trap simulator experiment

    International Nuclear Information System (INIS)

    Gilson, Erik P.; Chung, Moses; Davidson, Ronald C.; Efthimion, Philip C.; Majeski, Richard; Startsev, Edward A.

    2005-01-01

    The Paul Trap Simulator Experiment (PTSX) simulates the propagation of intense charged particle beams over distances of many kilometers through magnetic alternating-gradient (AG) transport systems by making use of the similarity between the transverse dynamics of particles in the two systems. One-component pure ion plasmas have been trapped that correspond to normalized intensity parameter s-coret=ω p 2 (0)/2ω q 2 = p (r) is the plasma frequency and ω q is the average transverse focusing frequency in the smooth-focusing approximation. The PTSX device confines one-component cesium ion plasmas for hundreds of milliseconds, which is equivalent to beam propagation over 10km. Results are presented for experiments in which the amplitude of the confining voltage waveform has been modified as a function of time. Recent modifications to the device are described, and both the change from a cesium ion source to a barium ion source, and the development of a laser-induced fluorescence diagnostic system are discussed

  20. Reactive transport models and simulation with ALLIANCES

    International Nuclear Information System (INIS)

    Leterrier, N.; Deville, E.; Bary, B.; Trotignon, L.; Hedde, T.; Cochepin, B.; Stora, E.

    2009-01-01

    Many chemical processes influence the evolution of nuclear waste storage. As a result, simulations based only upon transport and hydraulic processes fail to describe adequately some industrial scenarios. We need to take into account complex chemical models (mass action laws, kinetics...) which are highly non-linear. In order to simulate the coupling of these chemical reactions with transport, we use a classical Sequential Iterative Approach (SIA), with a fixed point algorithm, within the mainframe of the ALLIANCES platform. This approach allows us to use the various transport and chemical modules available in ALLIANCES, via an operator-splitting method based upon the structure of the chemical system. We present five different applications of reactive transport simulations in the context of nuclear waste storage: 1. A 2D simulation of the lixiviation by rain water of an underground polluted zone high in uranium oxide; 2. The degradation of the steel envelope of a package in contact with clay. Corrosion of the steel creates corrosion products and the altered package becomes a porous medium. We follow the degradation front through kinetic reactions and the coupling with transport; 3. The degradation of a cement-based material by the injection of an aqueous solution of zinc and sulphate ions. In addition to the reactive transport coupling, we take into account in this case the hydraulic retroaction of the porosity variation on the Darcy velocity; 4. The decalcification of a concrete beam in an underground storage structure. In this case, in addition to the reactive transport simulation, we take into account the interaction between chemical degradation and the mechanical forces (cracks...), and the retroactive influence on the structure changes on transport; 5. The degradation of the steel envelope of a package in contact with a clay material under a temperature gradient. In this case the reactive transport simulation is entirely directed by the temperature changes and

  1. Simulating the Long-Distance Propagation of Intense Beams in the Paul Trap Simulator Experiment

    CERN Document Server

    Gilson, Erik P; Davidson, Ronald C; Efthimion, Philip; Majeski, Richard; Startsev, Edward

    2005-01-01

    The Paul Trap Simulator Experiment (PTSX) makes use of a compact Paul trap configuration with quadrupolar oscillating wall voltages to simulate the propagation of intense charged particle beams over distances of many kilometers through magnetic alternating-gradient transport systems. The simulation is possible because of the similarity between the transverse dynamics of particles in the two systems. One-component pure cesium ion plasmas have been trapped that correspond to normalized intensity parameters s < 0.8, where s is the ratio of the square of the plasma frequency to twice the square of the average transverse focusing frequency. The PTSX device confines the plasma for hundreds of milliseconds, which is equivalent to beam propagation over tens of kilometers. Results are presented for experiments in which the amplitude of the oscillating confining voltage waveform has been modified as a function of time. A comparison is made between abrupt changes in amplitude and adiabatic changes in amplitude. T...

  2. Beam collimation and transport of quasineutral laser-accelerated protons by a solenoid field

    International Nuclear Information System (INIS)

    Harres, K.; Alber, I.; Guenther, M.; Nuernberg, F.; Otten, A.; Schuetrumpf, J.; Roth, M.; Tauschwitz, A.; Bagnoud, V.; Daido, H.; Tampo, M.; Schollmeier, M.

    2010-01-01

    This article reports about controlling laser-accelerated proton beams with respect to beam divergence and energy. The particles are captured by a pulsed high field solenoid with a magnetic field strength of 8.6 T directly behind a flat target foil that is irradiated by a high intensity laser pulse. Proton beams with energies around 2.3 MeV and particle numbers of 10 12 could be collimated and transported over a distance of more than 300 mm. In contrast to the protons the comoving electrons are strongly deflected by the solenoid field. They propagate at a submillimeter gyroradius around the solenoid's axis which could be experimentally verified. The originated high flux electron beam produces a high space charge resulting in a stronger focusing of the proton beam than expected by tracking results. Leadoff particle-in-cell simulations show qualitatively that this effect is caused by space charge attraction due to the comoving electrons. The collimation and transport of laser-accelerated protons is the first step to provide these unique beams for further applications such as postacceleration by conventional accelerator structures.

  3. Simulator for beam-based LHC collimator alignment

    Science.gov (United States)

    Valentino, Gianluca; Aßmann, Ralph; Redaelli, Stefano; Sammut, Nicholas

    2014-02-01

    In the CERN Large Hadron Collider, collimators need to be set up to form a multistage hierarchy to ensure efficient multiturn cleaning of halo particles. Automatic algorithms were introduced during the first run to reduce the beam time required for beam-based setup, improve the alignment accuracy, and reduce the risk of human errors. Simulating the alignment procedure would allow for off-line tests of alignment policies and algorithms. A simulator was developed based on a diffusion beam model to generate the characteristic beam loss signal spike and decay produced when a collimator jaw touches the beam, which is observed in a beam loss monitor (BLM). Empirical models derived from the available measurement data are used to simulate the steady-state beam loss and crosstalk between multiple BLMs. The simulator design is presented, together with simulation results and comparison to measurement data.

  4. Light ion beam transport research at NRL

    International Nuclear Information System (INIS)

    Hinshelwood, D.D.; Boller, J.R.; Cooperstein, G.

    1996-01-01

    Transport of light ion beams through low-pressure background gas is under investigation at NRL in support of the light-ion ICF program at Sandia National Laboratories. Scaling experiments and the field solver/orbit code ATHETA have been used to design and construct a focusing, extraction applied-B diode for transport experiments. An active anode source has been developed to provide a high proton fraction in the ion beam and a fast ion turn-on time. A very sensitive Zeeman diagnostic is being developed to determine the net current distribution in the beam/transport system. Both analytical and numerical techniques using several codes are being applied to transport modeling, leading to the capability of full system studies. (author). 1 tab., 5 figs., 10 refs

  5. Light ion beam transport research at NRL

    Energy Technology Data Exchange (ETDEWEB)

    Hinshelwood, D D; Boller, J R; Cooperstein, G [Naval Research Lab., Washington, DC (United States). Plasma Physics Div.; and others

    1997-12-31

    Transport of light ion beams through low-pressure background gas is under investigation at NRL in support of the light-ion ICF program at Sandia National Laboratories. Scaling experiments and the field solver/orbit code ATHETA have been used to design and construct a focusing, extraction applied-B diode for transport experiments. An active anode source has been developed to provide a high proton fraction in the ion beam and a fast ion turn-on time. A very sensitive Zeeman diagnostic is being developed to determine the net current distribution in the beam/transport system. Both analytical and numerical techniques using several codes are being applied to transport modeling, leading to the capability of full system studies. (author). 1 tab., 5 figs., 10 refs.

  6. Beam transport physics issues for the recirculating linear accelerator

    International Nuclear Information System (INIS)

    Shokair, I.R.

    1992-11-01

    The Recirculating Linear Accelerator (RLA) utilizes the Ion Focused Regime (IFR) of beam transport plus a ramped bending field to guide the beam around the curved sections. Several issues of beam transport are considered. Beam transverse perturbations that could result in growth of the ion hose instability are analyzed. It is found that transverse kicks due to bending field errors, energy mismatches and fringe fields are the most important. The scaling of these perturbations with beam and channel parameters is derived. The effect of ramping of the bending field on the preformed plasma channel is then considered. For RLA experimental parameters the effect is found to be very small. For high energies however, in addition to axial heating, it is found that ramping the field causes compression of the plasma channel along the radius of curvature. This compression results in a quasi-equilibrium plasma electron temperature along the field lines which leads to collisionless transport towards the walls. The analysis of compression is done in an approximate way using a single particle picture and the channel expansion is analyzed using an envelope solution which gives a simple expression for the expansion time. This solution is then verified by Buckshot simulations. For a bending field of 2 kG ramped in 2 μ-secs and an argon channel (RLA parameters) we estimate that the channel radius doubling time (along field lines) is of the order of 0.5 μ-secs. Finally the effect of electron impact ionization due to axially heated electrons by the action of the inductive field is estimated. It is found that in Argon gas the electron avalanche time could be as low as 0.5 μ-sec which is smaller than the field ramp time

  7. High-Energy Beam Transport in the Hanford FMIT Linear Accelerator

    International Nuclear Information System (INIS)

    Melson, K.E.; Potter, R.C.; Liska, D.J.; Giles, P.M.; Wilson, M.T.; Cole, T.R.; Caldwell, C.J. Jr.

    1979-01-01

    The High-Energy Beam Transport (HEBT) for the Hanford Fusion Materials Irradiation Test (FMIT) Facility's Linear Accelerator must transport a large emittance, high-current, high-power continuous duty deuteron beam with a large energy spread. Both periodic and nonperiodic systems have been designed to transport and shape the beam as required by the liquid lithium target. An energy spreader system distributes the Bragg Peak within the lithium. A beam spreader and a beam stop have been provided for tune-up purposes. Characterizing the beam will require extensions of beam diagnostics techniques and non-interceptive sensors. Provisions are being made in the facility for suspending the transport system from overhead supports

  8. Comparison of experimental and Monte-Carlo simulation of MeV particle transport through tapered/straight glass capillaries and circular collimators

    Energy Technology Data Exchange (ETDEWEB)

    Hespeels, F., E-mail: felicien.hespeels@unamur.be [University of Namur, PMR, 61 rue de Bruxelles, 5000 Namur (Belgium); Tonneau, R. [University of Namur, PMR, 61 rue de Bruxelles, 5000 Namur (Belgium); Ikeda, T. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Lucas, S. [University of Namur, PMR, 61 rue de Bruxelles, 5000 Namur (Belgium)

    2015-11-01

    Highlights: • Monte-Carlo simulation for beam transportation through collimations devices. • We confirm the focusing effect of tapered glass capillary. • We confirm the feasibility of using passive collimation devices for ion beam analysis application. - Abstract: This study compares the capabilities of three different passive collimation devices to produce micrometer-sized beams for proton and alpha particle beams (1.7 MeV and 5.3 MeV respectively): classical platinum TEM-like collimators, straight glass capillaries and tapered glass capillaries. In addition, we developed a Monte-Carlo code, based on the Rutherford scattering theory, which simulates particle transportation through collimating devices. The simulation results match the experimental observations of beam transportation through collimators both in air and vacuum. This research shows the focusing effects of tapered capillaries which clearly enable higher transmission flux. Nevertheless, the capillaries alignment with an incident beam is a prerequisite but is tedious, which makes the TEM collimator the easiest way to produce a 50 μm microbeam.

  9. Plasma channels for electron beam transport

    International Nuclear Information System (INIS)

    Schneider, R.F.; Smith, J.R.; Moffatt, M.E.; Nguyen, K.T.; Uhm, H.S.

    1988-01-01

    In recent years, there has been much interest in transport of intense relativistic electron beams using plasma channels. These channels are formed by either: ionization of an organic gas by UV photoionization or electron impact ionization of a low pressure gas utilizing a low energy (typically several hundred volts) electron gun. The second method is discussed here. As their electron gun, the authors used a 12 volt lightbulb filament which is biased to -400 volts with respect to the grounded 15 cm diameter drift tube. The electrons emitted from the filament are confined by an axial magnetic field of --100 Gauss to create a plasma channel which is less than 1 cm in radius. The channel density has been determined with Langmuir probes and the resulting line densities were found to be 10 11 to 10 12 per cm. When a multi-kiloamp electron beam is injected onto this channel, the beam space charge will eject the plasma electrons leaving the ions behind to charge neutralize the electron beam, hence allowing the beam to propagate. In this work, the authors performed experimental studies on the dynamics of the plasma channel. These include Langmuir probe measurements of a steady state (DC) channel, as well as time-resolved Langmuir probe studies of pulsed channels. In addition they performed experimental studies of beam propagation in these plasma channels. Specifically, they observed the behavior of current transport in these channels. Detailed results of beam transport and channel studies are presented

  10. Heavy ion beam fusion theory and simulation: Annual report, October 1985 to 31 January 1987

    International Nuclear Information System (INIS)

    Haber, I.

    1987-01-01

    A large number of simulations have been performed to establish a database of simulations for use in accelerator designs, and to compare the simulated emittance growths with the threshold for emittance growth actually measured in the Single Beam Transport Experiment (SBTE) at LBL. These simulations show substantial agreement with the experiment. They also extend into the parameter regime, where emittance growths are slower than could be measured in SBTE, but which may still be important to a driver system several times longer. Also demonstrated by these simulations, is that, even for beams which are not in detailed space-charge equilibrium and can therefore be subject to substantial nonlinear space-charge forces, emittance growths are restricted to what is consistent with energy conservation provided that the instability threshold is not crossed. This occurs even though energy need not be conserved in alternating gradient systems. Major modifications have been made to the two dimensional SHIFT-XY (Simulation of Heavy Ion Fusion Transport) code to add some of the three-dimensional physics associated with the transverse variation of the longitudinal fields in a long beam. Enhancements to the code have also been implemented which can decrease running times as much as 30% for typical parameters. 13 refs., 7 figs

  11. Nonlinear transport of accelerator beam phase space

    International Nuclear Information System (INIS)

    Xie Xi; Xia Jiawen

    1995-01-01

    Based on the any order analytical solution of accelerator beam dynamics, the general theory for nonlinear transport of accelerator beam phase space is developed by inverse transformation method. The method is general by itself, and hence can also be applied to the nonlinear transport of various dynamic systems in physics, chemistry and biology

  12. Issues and opportunities: beam simulations for heavy ion fusion

    International Nuclear Information System (INIS)

    Friedman, A

    1999-01-01

    UCRL- JC- 134975 PREPRINT code offering 3- D, axisymmetric, and ''transverse slice'' (steady flow) geometries, with a hierarchy of models for the ''lattice'' of focusing, bending, and accelerating elements. Interactive and script- driven code steering is afforded through an interpreter interface. The code runs with good parallel scaling on the T3E. Detailed simulations of machine segments and of complete small experiments, as well as simplified full- system runs, have been carried out, partially benchmarking the code. A magnetoinductive model, with module impedance and multi- beam effects, is under study. experiments, including an injector scalable to multi- beam arrays, a high- current beam transport and acceleration experiment, and a scaled final- focusing experiment. These ''phase I'' projects are laying the groundwork for the next major step in HIF development, the Integrated Research Experiment (IRE). Simulations aimed directly at the IRE must enable us to: design a facility with maximum power on target at minimal cost; set requirements for hardware tolerances, beam steering, etc.; and evaluate proposed chamber propagation modes. Finally, simulations must enable us to study all issues which arise in the context of a fusion driver, and must facilitate the assessment of driver options. In all of this, maximum advantage must be taken of emerging terascale computer architectures, requiring an aggressive code development effort. An organizing principle should be pursuit of the goal of integrated and detailed source- to- target simulation. methods for analysis of the beam dynamics in the various machine concepts, using moment- based methods for purposes of design, waveform synthesis, steering algorithm synthesis, etc. Three classes of discrete- particle models should be coupled: (1) electrostatic/ magnetoinductive PIC simulations should track the beams from the source through the final- focusing optics, passing details of the time- dependent distribution function to

  13. An integrated high-performance beam optics-nuclear processes framework with hybrid transfer map-Monte Carlo particle transport and optimization

    Energy Technology Data Exchange (ETDEWEB)

    Bandura, L., E-mail: bandura@msu.ed [Argonne National Laboratory, Argonne, IL 60439 (United States); Erdelyi, B. [Argonne National Laboratory, Argonne, IL 60439 (United States); Northern Illinois University, DeKalb, IL 60115 (United States); Nolen, J. [Argonne National Laboratory, Argonne, IL 60439 (United States)

    2010-12-01

    An integrated beam optics-nuclear processes framework is essential for accurate simulation of fragment separator beam dynamics. The code COSY INFINITY provides powerful differential algebraic methods for modeling and beam dynamics simulations in absence of beam-material interactions. However, these interactions are key for accurately simulating the dynamics of heavy ion fragmentation and fission. We have developed an extended version of the code that includes these interactions, and a set of new tools that allow efficient and accurate particle transport: by transfer map in vacuum and by Monte Carlo methods in materials. The new framework is presented, along with several examples from a preliminary layout of a fragment separator for a facility for rare isotope beams.

  14. An integrated high-performance beam optics-nuclear processes framework with hybrid transfer map-Monte Carlo particle transport and optimization

    International Nuclear Information System (INIS)

    Bandura, L.; Erdelyi, B.; Nolen, J.

    2010-01-01

    An integrated beam optics-nuclear processes framework is essential for accurate simulation of fragment separator beam dynamics. The code COSY INFINITY provides powerful differential algebraic methods for modeling and beam dynamics simulations in absence of beam-material interactions. However, these interactions are key for accurately simulating the dynamics of heavy ion fragmentation and fission. We have developed an extended version of the code that includes these interactions, and a set of new tools that allow efficient and accurate particle transport: by transfer map in vacuum and by Monte Carlo methods in materials. The new framework is presented, along with several examples from a preliminary layout of a fragment separator for a facility for rare isotope beams.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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

  17. Systematic comparison of position and time dependent macroparticle simulations in beam dynamics studies

    Directory of Open Access Journals (Sweden)

    Ji Qiang

    2002-06-01

    Full Text Available Macroparticle simulation plays an important role in modern accelerator design and operation. Most linear rf accelerators have been designed based on macroparticle simulations using longitudinal position as the independent variable. In this paper, we have done a systematic comparison between using longitudinal position as the independent variable and using time as the independent variable in macroparticle simulations. We have found that, for an rms-matched beam, the maximum relative moment difference for second, fourth moments and beam maximum amplitudes between these two types of simulations is 0.25% in a 10 m reference transport system with physical parameters similar to the Spallation Neutron Source linac design. The maximum z-to- t transform error in the space-charge force calculation of the position dependent simulation is about 0.1% in such a system. This might cause a several percent error in a complete simulation of a linac with a length of hundreds of meters. Furthermore, the error may be several times larger in simulations of mismatched beams. However, if such errors are acceptable to the linac designer, then one is justified in using position dependent macroparticle simulations in this type of linac design application.

  18. Electron beam simulation applicators

    International Nuclear Information System (INIS)

    Purdy, J.A.

    1983-01-01

    A system for simulating electron beam treatment portals using low-temperature melting point alloy is described. Special frames having the same physical dimensions as the electron beam applicators used on the Varian Clinac 20 linear accelerator were designed and constructed

  19. Design of the prototype of a beam transport line for handling and selection of low energy laser-driven beams

    Energy Technology Data Exchange (ETDEWEB)

    Schillaci, F., E-mail: francesco.schillaci@eli-beams.eu [INFN-LNS, Catania (Italy); Maggiore, M. [INFN-LNL, Legnaro (Italy); Cirrone, G.A.P.; Cuttone, G.; Pisciotta, P.; Costa, M.; Rifuggiato, D.; Romano, F. [INFN-LNS, Catania (Italy); Scuderi, V. [INFN-LNS, Catania (Italy); Institute of Physics of the ASCR, ELI-Beamlines Project, Prague (Czech Republic)

    2016-11-21

    A first prototype of transport beam-line for laser-driven ion beams to be used for the handling of particles accelerated by high-power laser interacting with solid targets has been realized at INFN. The goal is the production of a controlled and stable beam in terms of energy and angular spread. The beam-line consists of two elements: an Energy Selection System (ESS), already realized and characterized with both conventional and laser-accelerated beams, and a Permanent Magnet Quadrupole system (PMQ) designed, in collaboration with SIGMAPHI (Fr), to improve the ESS performances. In this work a description of the ESS system and some results of its characterization with conventional beams are reported, in order to provide a complete explanation of the acceptance calculation. Then, the matching with the PMQ system is presented and, finally, the results of preliminary simulations with a realistic laser-driven energy spectrum are discussed demonstrating the possibility to provide a good quality beam downstream the systems.

  20. Oxygen transport properties estimation by DSMC-CT simulations

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, Domenico [Istituto di Metodologie Inorganiche e dei Plasmi, Consiglio Nazionale delle Ricerche - Via G. Amendola, 122 - 70125 Bari (Italy); Frezzotti, Aldo; Ghiroldi, Gian Pietro [Dipartimento di Scienze e Tecnologie Aerospaziali, Politecnico di Milano - Via La Masa, 34 - 20156 Milano (Italy)

    2014-12-09

    Coupling DSMC simulations with classical trajectories calculations is emerging as a powerful tool to improve predictive capabilities of computational rarefied gas dynamics. The considerable increase of computational effort outlined in the early application of the method (Koura,1997) can be compensated by running simulations on massively parallel computers. In particular, GPU acceleration has been found quite effective in reducing computing time (Ferrigni,2012; Norman et al.,2013) of DSMC-CT simulations. The aim of the present work is to study rarefied Oxygen flows by modeling binary collisions through an accurate potential energy surface, obtained by molecular beams scattering (Aquilanti, et al.,1999). The accuracy of the method is assessed by calculating molecular Oxygen shear viscosity and heat conductivity following three different DSMC-CT simulation methods. In the first one, transport properties are obtained from DSMC-CT simulations of spontaneous fluctuation of an equilibrium state (Bruno et al, Phys. Fluids, 23, 093104, 2011). In the second method, the collision trajectory calculation is incorporated in a Monte Carlo integration procedure to evaluate the Taxman’s expressions for the transport properties of polyatomic gases (Taxman,1959). In the third, non-equilibrium zero and one-dimensional rarefied gas dynamic simulations are adopted and the transport properties are computed from the non-equilibrium fluxes of momentum and energy. The three methods provide close values of the transport properties, their estimated statistical error not exceeding 3%. The experimental values are slightly underestimated, the percentage deviation being, again, few percent.

  1. Modeling the biophysical effects in a carbon beam delivery line by using Monte Carlo simulations

    Science.gov (United States)

    Cho, Ilsung; Yoo, SeungHoon; Cho, Sungho; Kim, Eun Ho; Song, Yongkeun; Shin, Jae-ik; Jung, Won-Gyun

    2016-09-01

    The Relative biological effectiveness (RBE) plays an important role in designing a uniform dose response for ion-beam therapy. In this study, the biological effectiveness of a carbon-ion beam delivery system was investigated using Monte Carlo simulations. A carbon-ion beam delivery line was designed for the Korea Heavy Ion Medical Accelerator (KHIMA) project. The GEANT4 simulation tool kit was used to simulate carbon-ion beam transport into media. An incident energy carbon-ion beam with energy in the range between 220 MeV/u and 290 MeV/u was chosen to generate secondary particles. The microdosimetric-kinetic (MK) model was applied to describe the RBE of 10% survival in human salivary-gland (HSG) cells. The RBE weighted dose was estimated as a function of the penetration depth in the water phantom along the incident beam's direction. A biologically photon-equivalent Spread Out Bragg Peak (SOBP) was designed using the RBE-weighted absorbed dose. Finally, the RBE of mixed beams was predicted as a function of the depth in the water phantom.

  2. Design studies of an electrostatic quadrupole channel for transport of a high-brightness H- beam and comparison with gas focusing

    International Nuclear Information System (INIS)

    Chang, C.R.; Horowitz, E.; Reiser, M.

    1989-01-01

    Transport of low-energy, high-brightness H - beams from the ion source to the radio-frequency quadrupole (RFQ) accelerator requires the solution of several physics and engineering problems to avoid particle losses and emittance growth. The authors developed a conceptual design of an electrostatic quadrupole channel for transport of a 120 keV, 120 mA, H - beam into a 425 MHz RFQ with low emittance growth and high transmission efficiency. This design satisfies several constraints imposed by voltage breakdown and beam optics considerations. The system will consist entirely of electrostatic lenses which prevent plasma build-up and eliminate possible emittance growth from plasma fluctuations. Pertinent design features a worst case non-linear analysis for the electrostatic quadrupole channel, and first results of a particle simulation code used to study beam loss and emittance growth are reported. As an alternative to the electrostatic quadrupole concept, gas focusing is being investigated for transporting low-energy H - beams. Recent results from the numerical simulations of such a gas focussing channel are presented

  3. Simulations of beam ion transport during tearing modes in the DIII-D tokamak

    International Nuclear Information System (INIS)

    Carolipio, E.M.; Heidbrink, W.W.; Forest, C.B.; White, R.B.

    2002-01-01

    Large coherent MHD modes are observed to reduce the neutral beam current drive efficiency and 2.5 MeV neutron emission in DIII-D by as much as ∼65%. These modes result in large (width w or approx. 40 keV become stochastic at island widths comparable to those in the experiment. A Hamiltonian guiding centre code is used to follow energetic particle trajectories with the tearing mode modelled as a radially extended, single helicity perturbation. In the simulations, the lost neutral beam current drive and neutron emission are 35% and 40%, respectively, which is consistent with the measured reductions of 40±14% and 40±10%. Several features of the lost particle distribution indicate that orbit stochasticity is the loss mechanism in the simulations and strongly suggest that the same mechanism is responsible for the losses observed in the experiment. (author)

  4. Investigation of Beam Emittance and Beam Transport Line Optics on Polarization

    Energy Technology Data Exchange (ETDEWEB)

    Fiedler, Andrew [Northern Illinois U.; Syphers, Michael [Fermilab

    2017-10-06

    Effects of beam emittance, energy spread, optical parameters and magnet misalignment on beam polarization through particle transport systems are investigated. Particular emphasis will be placed on the beam lines being used at Fermilab for the development of the muon beam for the Muon g-2 experiment, including comparisons with the natural polarization resulting from pion decay, and comments on the development of systematic correlations among phase space variables.

  5. Low-energy beam transport studies supporting the spallation neutron source 1-MW beam operation.

    Science.gov (United States)

    Han, B X; Kalvas, T; Tarvainen, O; Welton, R F; Murray, S N; Pennisi, T R; Santana, M; Stockli, M P

    2012-02-01

    The H(-) injector consisting of a cesium enhanced RF-driven ion source and a 2-lens electrostatic low-energy beam transport (LEBT) system supports the spallation neutron source 1 MW beam operation with ∼38 mA beam current in the linac at 60 Hz with a pulse length of up to ∼1.0 ms. In this work, two important issues associated with the low-energy beam transport are discussed: (1) inconsistent dependence of the post-radio frequency quadrupole accelerator beam current on the ion source tilt angle and (2) high power beam losses on the LEBT electrodes under some off-nominal conditions compromising their reliability.

  6. Transport studies of LPA electron beam towards the FEL amplification at COXINEL

    Energy Technology Data Exchange (ETDEWEB)

    Khojoyan, M., E-mail: martin.khojoyan@synchrotron-soleil.fr; Briquez, F.; Labat, M.; Loulergue, A.; Marcouillé, O.; Marteau, F.; Sharma, G.; Couprie, M.E.

    2016-09-01

    Laser Plasma Acceleration (LPA) [1] is an emerging concept enabling to generate electron beams with high energy, high peak current and small transverse emittance within a very short distance. The use of LPA can be applied to the Free Electron Laser (FEL) [2] case in order to investigate whether it is suitable for the light amplification in the undulator. However, capturing and guiding of such beams to the undulator is very challenging, because of the large divergence and high energy spread of the electron beams at the plasma exit, leading to large chromatic emittances. A specific beam manipulation scheme was recently proposed for the COXINEL (Coherent X-ray source inferred from electrons accelerated by laser) setup, which makes an advantage from the intrinsically large chromatic emittance of such beams [3]. The electron beam transport is studied using two simulation codes: a SOLEIL in-house one and ASTRA [4]. The influence of the collective effects on the electron beam performance is also examined.

  7. H- beam neutralization measurements in a solenoidal beam transport system

    International Nuclear Information System (INIS)

    Sherman, J.; Pitcher, E.; Stevens, R.; Allison, P.

    1992-01-01

    H minus beam space-charge neutralization is measured for 65-mA, 35-keV beams extracted from a circular-aperture Penning surface-plasma source, the small-angle source. The H minus beam is transported to a RFQ matchpoint by a two-solenoid magnet system. Beam noise is typically ±4%. A four-grid analyzer is located in a magnetic-field-free region between the two solenoid magnets. H minus potentials are deduced from kinetic energy measurements of particles (electrons and positive ions) ejected radially from the beam channel by using a griddled energy analyzer. Background neutral gas density is increased by the introduction of additional Xe and Ar gases, enabling the H minus beam to become overneutralized

  8. Space Charge Compensation in the Linac4 Low Energy Beam Transport Line with Negative Hydrogen Ions

    CERN Document Server

    Valerio-Lizarraga, C; Leon-Monzon, I; Lettry, J; Midttun, O; Scrivens, R

    2014-01-01

    The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Tranport (LEBT) using the package IBSimu1, which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H- beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree.

  9. Beam-Beam Simulations with GUINEA-PIG

    CERN Document Server

    Schulte, Daniel

    1998-01-01

    While the bunches in a linear collider cross only once, due to their small size they experience a strong beam-beam effect. GUINEA-PIG is a code to simulate the impact of this effect on luminosity and back ground. A short overview of the program is given with examples of its application to the back ground strudies for TESLA, the top quark threshold scan and a possible luminosity monitor, as well as some results for CLIC.

  10. Electron and ion beam transport to fusion targets

    International Nuclear Information System (INIS)

    Freeman, J.R.; Baker, L.; Miller, P.A.; Mix, L.P.; Olsen, J.N.; Poukey, J.W.; Wright, T.P.

    1979-01-01

    ICF reactors have been proposed which incorporate a gas-filled chamber to reduce x-ray and debris loading of the first wall. Focused beams of either electrons or ions must be transported efficiently for 2-4 m to a centrally located fusion target. Laser-initiated current-carrying plasma discharge channels provide the guiding magnetic field and the charge- and current-neutralizing medium required for beam propagation. Computational studies of plasma channel formation in air using a 1-D MHD model with multigroup radiation diffusion have provided a good comparison with the expansions velocity and time dependent refractivity profile determined by holographic interferometry. Trajectory calculations have identified a beam expansion mechanism which combines with the usual ohmic dissipation to reduce somewhat the transported beam fluence for electrons. Additional trajectory calculations have been performed for both electrons and light ions to predict the limits on the particle current density which can be delivered to a central target by overlapping the many independently-generated beams. Critical features of the use of plasma channels for transport and overlap of charged particle beams are being tested experimentally with up to twelve electron beams from the Proto II accelerator

  11. Relativistic electron-beam transport in curved channels

    International Nuclear Information System (INIS)

    Vittitoe, C.N.; Morel, J.E.; Wright, T.P.

    1982-01-01

    Collisionless single particle trajectories are modeled for a single plasma channel having one section curved in a circular arc. The magnetic field is developed by superposition of straight and curved channel segments. The plasma density gives charge and beam-current neutralization. High transport efficiencies are found for turning a relativistic electron beam 90 0 under reasonable conditions of plasma current, beam energy, arc radius, channel radius, and injection distributions in velocity and in position at the channel entrance. Channel exit distributions in velocity and position are found consistent with those for a straight plasma channel of equivalent length. Such transport problems are important in any charged particle-beam application constrained by large diode-to-target distance or by requirements of maximum power deposition in a confined area

  12. Beam Transport Devices for the 10 kW IR Free Electron Laser

    International Nuclear Information System (INIS)

    Lawrence Dillon-Townes; Michael Bevins; David Kashy; Stephanie Slachtouski; Ronald Lassiter; George Neil; Michelle Shinn; Joseph Gubeli; Christopher Behre; David Douglas; David W. Waldman; George Biallas; Lawrence Munk; Christopher Gould

    2005-01-01

    Beam transport components for the 10kW IR Free Electron Laser (FEL) at Thomas Jefferson National Accelerator Facility (Jefferson Lab) were designed to manage (1) electron beam transport and (2) photon beam transport. An overview of the components will be presented in this paper. The electron beam transport components were designed to address RF heating, maintain an accelerator transport vacuum of 1 x 10 -8 torr, deliver photons to the optical cavity, and provide 50 kW of beam absorption during the energy recovery process. The components presented include a novel shielded bellows, a novel zero length beam clipper, a one decade differential pumping station with a 7.62 cm (3.0 inch) aperture, and a 50 kW beam dump. The photon beam transport components were designed to address the management of photons delivered by the accelerator transport. The optical cavity manages the photons and optical transport delivers the 10 kW of laser power to experimental labs. The optical cavity component presented is a unique high reflector vessel and the optical transport component presented is a turning mirror cassette

  13. Simulations of the LEDA LEBT H+ beam

    International Nuclear Information System (INIS)

    Smith, H.V. Jr.; Sherman, J.D.; Stevens, R.R. Jr.; Young, L.M.

    1997-01-01

    The computer codes TRACE and SCHAR model the Low-Energy Demonstration Accelerator (LEDA) Low-Energy Beam Transport (LEBT) for 75-keV, 110-mA, dc H + beams. Solenoid-lens location studies verify that the proposed LEBT design gives a near-optimum match to the LEDA RFQ. The desired RFQ transmission (≥ 90%) and output emittance (≤ 0.22 π mm mrad, transverse) are obtained when PARMTEQM transports the file for the SCHAR-generated optimum beam through the RFQ

  14. Optimal transport of particle beams

    International Nuclear Information System (INIS)

    Allen, C.K.; Reiser, M.

    1997-01-01

    The transport and matching problem for a low energy transport system is approached from a control theoretical viewpoint. We develop a model for a beam transport and matching section based on a multistage control network. To this model we apply the principles of optimal control to formulate techniques aiding in the design of the transport and matching section. Both nonlinear programming and dynamic programming techniques are used in the optimization. These techniques are implemented in a computer-aided design program called SPOT. Examples are presented to demonstrate the procedure and outline the results. (orig.)

  15. Beam dynamics simulation of injector for high power CW electron linac in PNC

    International Nuclear Information System (INIS)

    Nomura, Masahiro; Yamazaki, Yoshio; Toyama, Shin-ichi

    1994-01-01

    The injector consists of a 200 kV DC gun, a RF chopper, a chopper slit, a prebuncher and a buncher. Solenoid coils covered from the exit of gun to accelerating tube 1 except between the RF chopper and chopper slit. Beam trajectories are simulated by PARMELA in order to design the injector. In this report, two simulation results are shown. One is for a beam trajectory from gun to solenoid coils. There is thick concrete wall between gun to RF chopper. Low energy electrons are transported through long solenoid coil area. The other is for a chopper part. The novel chopper system is designed to reduce the emittance growth. (author)

  16. Simulation and design of an electron beam ion source charge breeder for the californium rare isotope breeder upgrade

    Directory of Open Access Journals (Sweden)

    Clayton Dickerson

    2013-02-01

    Full Text Available An electron beam ion source (EBIS will be constructed and used to charge breed ions from the californium rare isotope breeder upgrade (CARIBU for postacceleration into the Argonne tandem linear accelerator system (ATLAS. Simulations of the EBIS charge breeder performance and the related ion transport systems are reported. Propagation of the electron beam through the EBIS was verified, and the anticipated incident power density within the electron collector was identified. The full normalized acceptance of the charge breeder with a 2 A electron beam, 0.024π  mm mrad for nominal operating parameters, was determined by simulating ion injection into the EBIS. The optics of the ion transport lines were carefully optimized to achieve well-matched ion injection, to minimize emittance growth of the injected and extracted ion beams, and to enable adequate testing of the charge bred ions prior to installation in ATLAS.

  17. Study on the beam transport from the Bio-Nano ECRIS

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, T. [Bio-Nano Electronics Research Centre, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585 (Japan); Minezaki, H.; Yoshida, Y. [Bio-Nano Electronics Research Centre, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585 (Japan); Graduate School of Engineering, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585 (Japan); Oshima, K. [Graduate School of Engineering, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585 (Japan); Racz, R.; Biri, S. [Institute of Nuclear Research (ATOMKI), H-4026 Debrecen, Bem ter 18/c (Hungary); Muramatsu, M.; Kitagawa, A. [National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555 (Japan); Asaji, T. [Tateyama Machine Co., Ltd., 30 Shimonoban, Toyama-shi, Toyama 930-1305 (Japan); Kato, Y. [Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871 (Japan)

    2012-02-15

    The beam transport of N{sup +} ion and C{sub 60}{sup +} ion in the Bio-Nano ECRIS with min-B configuration was investigated based on the ion beam profiles. The N{sup +} beam could be focused under the low-beam current conditions. Also the C{sub 60}{sup +} beam could be focused in spite of the large space-charge effect which will lead the divergence of the beam. We confirmed that our beam transport system works well even for the C{sub 60}{sup +} ion beam. We estimated the highest C{sub 60}{sup +} beam current with the focused beam profile by comparing the N{sup +} ion beam.

  18. Nonlinear hybrid simulation of internal kink with beam ion effects in DIII-D

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Wei; Sheng, Zheng-Mao [Department of Physics, Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China); Fu, G. Y.; Tobias, Benjamin [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Zeeland, Michael Van [General Atomics, San Diego, California 92186-5608 (United States); Wang, Feng [School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China)

    2015-04-15

    In DIII-D sawteething plasmas, long-lived (1,1) kink modes are often observed between sawtooth crashes. The saturated kink modes have two distinct frequencies. The mode with higher frequency transits to a fishbone-like mode with sufficient on-axis neutral beam power. In this work, hybrid simulations with the global kinetic-magnetohydrodynamic (MHD) hybrid code M3D-K have been carried out to investigate the linear stability and nonlinear dynamics of the n = 1 mode with effects of energetic beam ions for a typical DIII-D discharge where both saturated kink mode and fishbone were observed. Linear simulation results show that the n = 1 internal kink mode is unstable in MHD limit. However, with kinetic effects of beam ions, a fishbone-like mode is excited with mode frequency about a few kHz depending on beam pressure profile. The mode frequency is higher at higher beam power and/or narrower radial profile consistent with the experimental observation. Nonlinear simulations have been performed to investigate mode saturation as well as energetic particle transport. The nonlinear MHD simulations show that the unstable kink mode becomes a saturated kink mode after a sawtooth crash. With beam ion effects, the fishbone-like mode can also transit to a saturated kink mode with a small but finite mode frequency. These results are consistent with the experimental observation of saturated kink mode between sawtooth crashes.

  19. Design study of low-energy beam transport for multi-charge beams at RAON

    Science.gov (United States)

    Bahng, Jungbae; Qiang, Ji; Kim, Eun-San

    2015-12-01

    The Rare isotope Accelerator Of Newness (RAON) at the Rare Isotope Science Project (RISP) is being designed to simultaneously accelerate beams with multiple charge states. It includes a driver superconducting (SC) linac for producing 200 MeV/u and 400 kW continuous wave (CW) heavy ion beams from protons to uranium. The RAON consists of a few electron cyclotron resonance ion sources, a low-energy beam transport (LEBT) system, a CW 81.25 MHz, 500 keV/u radio frequency quadrupole (RFQ) accelerator, a medium-energy beam transport system, the SC linac, and a charge-stripper system. The LEBT system for the RISP accelerator facility consists of a high-voltage platform, two 90° dipoles, a multi-harmonic buncher (MHB), solenoids, electrostatic quadrupoles, a velocity equalizer, and a diagnostic system. The ECR ion sources are located on a high-voltage platform to reach an initial beam energy of 10 keV/u. After extraction, the ion beam is transported through the LEBT system to the RFQ accelerator. The generated charge states are selected by an achromatic bending system and then bunched by the MHB in the LEBT system. The MHB is used to achieve a small longitudinal emittance in the RFQ by generating a sawtooth wave with three harmonics. In this paper, we present the results and issues of the beam dynamics of the LEBT system.

  20. Design study of low-energy beam transport for multi-charge beams at RAON

    Energy Technology Data Exchange (ETDEWEB)

    Bahng, Jungbae [Department of Physics, Kyungpook National University, Daegu 41566 (Korea, Republic of); Qiang, Ji [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Kim, Eun-San, E-mail: eskim1@korea.ac.kr [Department of Accelerator Science, Graduate School, Korea University Sejong Campus, Sejong 30019 (Korea, Republic of)

    2015-12-21

    The Rare isotope Accelerator Of Newness (RAON) at the Rare Isotope Science Project (RISP) is being designed to simultaneously accelerate beams with multiple charge states. It includes a driver superconducting (SC) linac for producing 200 MeV/u and 400 kW continuous wave (CW) heavy ion beams from protons to uranium. The RAON consists of a few electron cyclotron resonance ion sources, a low-energy beam transport (LEBT) system, a CW 81.25 MHz, 500 keV/u radio frequency quadrupole (RFQ) accelerator, a medium-energy beam transport system, the SC linac, and a charge-stripper system. The LEBT system for the RISP accelerator facility consists of a high-voltage platform, two 90° dipoles, a multi-harmonic buncher (MHB), solenoids, electrostatic quadrupoles, a velocity equalizer, and a diagnostic system. The ECR ion sources are located on a high-voltage platform to reach an initial beam energy of 10 keV/u. After extraction, the ion beam is transported through the LEBT system to the RFQ accelerator. The generated charge states are selected by an achromatic bending system and then bunched by the MHB in the LEBT system. The MHB is used to achieve a small longitudinal emittance in the RFQ by generating a sawtooth wave with three harmonics. In this paper, we present the results and issues of the beam dynamics of the LEBT system.

  1. Transport of intense ion beams

    International Nuclear Information System (INIS)

    Lambertson, G.; Laslett, L.J.; Smith, L.

    1977-01-01

    The possibility of using intense bursts of heavy ions to initiate an inertially confined fusion reaction has stimulated interest in the transport of intense unneutralized heavy ion beams by quadrupole or solenoid systems. This problem was examined in some detail, using numerical integration of the coupled envelope equations for the quadrupole case. The general relations which emerge are used to develop examples of high energy transport systems and as a basis for discussing the limitations imposed by a transport system on achievable intensities for initial acceleration

  2. Optimizing beam transport in rapidly compressing beams on the neutralized drift compression experiment – II

    Directory of Open Access Journals (Sweden)

    Anton D. Stepanov

    2018-03-01

    Full Text Available The Neutralized Drift Compression Experiment-II (NDCX-II is an induction linac that generates intense pulses of 1.2 MeV helium ions for heating matter to extreme conditions. Here, we present recent results on optimizing beam transport. The NDCX-II beamline includes a 1-m-long drift section downstream of the last transport solenoid, which is filled with charge-neutralizing plasma that enables rapid longitudinal compression of an intense ion beam against space-charge forces. The transport section on NDCX-II consists of 28 solenoids. Finding optimal field settings for a group of solenoids requires knowledge of the envelope parameters of the beam. Imaging the beam on the scintillator gives the radius of the beam, but the envelope angle is not measured directly. We demonstrate how the parameters of the beam envelope (radius, envelop angle, and emittance can be reconstructed from a series of images taken by varying the B-field strengths of a solenoid upstream of the scintillator. We use this technique to evaluate emittance at several points in the NDCX-II beamline and for optimizing the trajectory of the beam at the entry of the plasma-filled drift section. Keywords: Charged-particle beams, Induction accelerators, Beam dynamics, Beam emittance, Ion beam diagnostics, PACS Codes: 41.75.-i, 41.85.Ja, 52.59.Sa, 52.59.Wd, 29.27.Eg

  3. Transport channel of secondary ion beam of experimental setup for selective laser ionization with gas cell GALS

    Science.gov (United States)

    Gulbekyan, G. G.; Zemlyanoy, S. G.; Bashevoy, V. V.; Ivanenko, I. A.; Kazarinov, N. Yu; Kazacha, V. I.; Osipov, N. F.

    2017-07-01

    GALS is the experimental setup intended for production and research of isobaric and isotopically pure heavy neutron-rich nuclei. The beam line consists of two parts. The initial part is used for transport of the primary 136Xe ion beam with the energy of 4.5-9.0 MeV/amu from the FLNR cyclotron U-400M to the Pb target for production of the studying ion beams. These beams have the following design parameters: the charge Z = +1, the mass A = 180-270 and the kinetic energy W = 40 keV. The second part placed after the target consists of the SPIG (QPIG) system, the accelerating gap, the electrostatic Einzel lens, 90-degree spectrometric magnet (calculated value of the mass-resolution is equal to 1400) and the beam line for the transportation of the ions from the magnet focal plane to a particle detector. The results of simulation of the particle dynamics and the basic parameters of all elements of the beam line are presented.

  4. Mitigation of numerical noise for beam loss simulations

    CERN Document Server

    Kesting, Frederik

    2017-01-01

    Numerical noise emerges in self-consistent simulations of charged particles, and its mitigation is investigated since the first numerical studies in plasma physics. In accelerator physics, recent studies find an artificial diffusion of the particle beam due to numerical noise in particle-in-cell tracking, which is of particular importance for high intensity machines with a long storage time, as the SIS100 at FAIR or in context of the LIU upgrade at CERN. In beam loss simulations for these projects artificial effects must be distinguished from physical beam loss. Therefore, it is important to relate artificial diffusion to artificial beam loss, and to choose simulation parameters such that physical beam loss is well resolved. As a practical tool, we therefore suggest a scaling law to find optimal simulation parameters for a given maximum percentage of acceptable artificial beam loss.

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

    International Nuclear Information System (INIS)

    Douglas, D.R.

    1986-01-01

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

  6. Generalized emittance measurements in a beam transport line

    International Nuclear Information System (INIS)

    Skelly, J.; Gardner, C.; Luccio, A.; Kponou, A.; Reece, K.

    1991-01-01

    Motivated by the need to commission 3 beam transport lines for the new AGS Booster project, we have developed a generalized emittance-measurement program; beam line specifics are entirely resident in data tables, not in program code. For instrumentation, the program requires one or more multi-wire profile monitors; one or multiple profiles are acquired from each monitor, corresponding to one or multiple tunes of the transport line. Emittances and Twiss parameters are calculated using generalized algorithms. The required matix descriptions of the beam optics are constructed by an on-line general beam modeling program. Design of the program, its algorithms, and initial experience with it will be described. 4 refs., 2 figs., 1 tab

  7. Beam line design for a low energy electron beam

    International Nuclear Information System (INIS)

    Arvind Kumar; Mahadevan, S.

    2002-01-01

    The design of a beam line for transport of a 70 keV electron beam from a thermionic gun to the Plane Wave Transformer (PWT) linac incorporating two solenoid magnets, a beam profile monitor and drift sections is presented. We used beam dynamics codes EGUN, PARMELA and compare simulated results with analytical calculations. (author)

  8. The calculation, simulation, and measurement of longitudinal beam dynamics in electron injectors

    International Nuclear Information System (INIS)

    Dunham, B.; Liu, H.; Kazimi, R.

    1997-01-01

    Polarized electrons are a valuable commodity for nuclear physics research and every effort must be made to preserve them during transport Measurements of the beam emitted from the polarized source at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) have shown a considerable bunch lengthening with increasing beam current. This lengthening leads to unacceptable loss as the beam passes through the injector chopping system. We present an application of the longitudinal envelope equation to describe the bunch lengthening and compare the results to measurements and simulations using PARMELA. In addition, a possible solution to the problem by adding a low power buncher to the beamline is described and initial results are shown

  9. Positron deposition in plasmas by positronium beam ionization and transport of positrons in tokamak plasmas

    International Nuclear Information System (INIS)

    Murphy, T.J.

    1986-11-01

    In a recently proposed positron transport experiment, positrons would be deposited in a fusion plasma by forming a positronium (Ps) beam and passing it through the plasma. Positrons would be deposited as the beam is ionized by plasma ions and electrons. Radial transport of the positrons to the limiter could then be measured by detecting the gamma radiation produced by annihilation of positrons with electrons in the limiter. This would allow measurements of the transport of electron-mass particles and might shed some light on the mechanisms of electron transport in fusion plasmas. In this paper, the deposition and transport of positrons in a tokamak are simulated and the annihilation signal determined for several transport models. Calculations of the expected signals are necessary for the optimal design of a positron transport experiment. There are several mechanisms for the loss of positrons besides transport to the limiter. Annihilation with plasma electrons and reformation of positronium in positron-hydrogen collisions are two such processes. These processes can alter the signal and place restrictions ons on the plasma conditions in which positron transport experiments can be effectively performed

  10. Coherent resonance stop bands in alternating gradient beam transport

    Science.gov (United States)

    Ito, K.; Okamoto, H.; Tokashiki, Y.; Fukushima, K.

    2017-06-01

    An extensive experimental study is performed to confirm fundamental resonance bands of an intense hadron beam propagating through an alternating gradient linear transport channel. The present work focuses on the most common lattice geometry called "FODO" or "doublet" that consists of two quadrupoles of opposite polarities. The tabletop ion-trap system "S-POD" (Simulator of Particle Orbit Dynamics) developed at Hiroshima University is employed to clarify the parameter-dependence of coherent beam instability. S-POD can provide a non-neutral plasma physically equivalent to a charged-particle beam in a periodic focusing potential. In contrast with conventional experimental approaches relying on large-scale machines, it is straightforward in S-POD to control the doublet geometry characterized by the quadrupole filling factor and drift-space ratio. We verify that the resonance feature does not essentially change depending on these geometric factors. A few clear stop bands of low-order resonances always appear in the same pattern as previously found with the sinusoidal focusing model. All stop bands become widened and shift to the higher-tune side as the beam density is increased. In the space-charge-dominated regime, the most dangerous stop band is located at the bare betatron phase advance slightly above 90 degrees. Experimental data from S-POD suggest that this severe resonance is driven mainly by the linear self-field potential rather than by nonlinear external imperfections and, therefore, unavoidable at high beam density. The instability of the third-order coherent mode generates relatively weak but noticeable stop bands near the phase advances of 60 and 120 degrees. The latter sextupole stop band is considerably enhanced by lattice imperfections. In a strongly asymmetric focusing channel, extra attention may have to be paid to some coupling resonance lines induced by the Coulomb potential. Our interpretations of experimental data are supported by theoretical

  11. Simulation of the Beam Dump for a High Intensity Electron Gun

    CERN Document Server

    Doebert, S; Lefevre, T; Pepitone, K

    2014-01-01

    The CLIC Drive Beam is a high-intensity pulsed electron beam. A test facility for the Drive Beam electron gun will soon be commissioned at CERN. In this contribution we outline the design of a beam dump / Faraday cup capable of resisting the beam’s thermal load. The test facility will operate initially up to 140 keV. At such low energies, the electrons are absorbed very close to the surface of the dump, leading to a large energy deposition density in this thin layer. In order not to damage the dump, the beam must be spread over a large surface. For this reason, a small-angled cone has been chosen. Simulations using Geant4 have been performed to estimate the distribution of energy deposition in the dump. The heat transport both within the electron pulse and between pulses has been modelled using finite element methods to check the resistance of the dump at high repetition rates. In addition, the possibility of using a moveable dump to measure the beam profile and emittance is discussed.

  12. Extraction design and low energy beam transport optimization of space charge dominated multispecies ion beam sources

    International Nuclear Information System (INIS)

    Delferriere, O.; De Menezes, D.

    2004-01-01

    In all accelerator projects, the low energy part of the accelerator has to be carefully optimized to match the beam characteristic requirements of the higher energy parts. Since 1994 with the beginning of the Injector of Protons for High Intensity (IPHI) project and Source of Light Ions with High Intensities (SILHI) electron cyclotron resonance (ECR) ion source development at CEA/Saclay, we are using a set of two-dimensional (2D) codes for extraction system optimization (AXCEL, OPERA-2D) and beam transport (MULTIPART). The 95 keV SILHI extraction system optimization has largely increased the extracted current, and improved the beam line transmission. From these good results, a 130 mA D + extraction system for the International Fusion Material Irradiation Facility project has been designed in the same way as SILHI one. We are also now involved in the SPIRAL 2 project for the building of a 40 keV D + ECR ion source, continuously tunable from 0.1 to 5 mA, for which a special four-electrode extraction system has been studied. In this article we will describe the 2D design process and present the different extraction geometries and beam characteristics. Simulation results of SILHI H + beam emittance will be compared with experimental measurements

  13. Transport of intense particle beams with application to heavy ion fusion

    International Nuclear Information System (INIS)

    Buchanan, H.L.; Chambers, F.W.; Lee, E.P.; Yu, S.S.; Briggs, R.J.; Rosenbluth, M.N.

    1979-01-01

    An attractive feature of the high energy (> GeV) heavy ion beam approach to inertial fusion, as compared with other particle beam systems, is the relative simplicity involved in the transport and focusing of energy on the target inside a reactor chamber. While this focusing could be done in vacuum by conventional methods with multiple beams, there are significant advantages in reactor design if one can operate at gas pressures around one torr. In this paper we summarize the results of our studies of heavy ion beam transport in gases. With good enough charge and current neutralization, one could get a ballistically-converging beam envelope down to a few millimeters over a 10 meter path inside the chamber. Problems of beam filamentation place important restrictions on this approach. We also discuss transport in a self-focused mode, where a relatively stable pressure window is predicted similar to the observed window for electron beam transport

  14. Dust particle diffusion in ion beam transport region

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, N.; Okajima, Y.; Romero, C. F.; Kuwata, Y.; Kasuya, T.; Wada, M., E-mail: mwada@mail.doshisha.ac.jp [Graduate school of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321 (Japan)

    2016-02-15

    Dust particles of μm size produced by a monoplasmatron ion source are observed by a laser light scattering. The scattered light signal from an incident laser at 532 nm wavelength indicates when and where a particle passes through the ion beam transport region. As the result, dusts with the size more than 10 μm are found to be distributed in the center of the ion beam, while dusts with the size less than 10 μm size are distributed along the edge of the ion beam. Floating potential and electron temperature at beam transport region are measured by an electrostatic probe. This observation can be explained by a charge up model of the dust in the plasma boundary region.

  15. Computationally efficient description of relativistic electron beam transport in dense plasma

    Science.gov (United States)

    Polomarov, Oleg; Sefkov, Adam; Kaganovich, Igor; Shvets, Gennady

    2006-10-01

    A reduced model of the Weibel instability and electron beam transport in dense plasma is developed. Beam electrons are modeled by macro-particles and the background plasma is represented by electron fluid. Conservation of generalized vorticity and quasineutrality of the plasma-beam system are used to simplify the governing equations. Our approach is motivated by the conditions of the FI scenario, where the beam density is likely to be much smaller than the plasma density and the beam energy is likely to be very high. For this case the growth rate of the Weibel instability is small, making the modeling of it by conventional PICs exceedingly time consuming. The present approach does not require resolving the plasma period and only resolves a plasma collisionless skin depth and is suitable for modeling a long-time behavior of beam-plasma interaction. An efficient code based on this reduced description is developed and benchmarked against the LSP PIC code. The dynamics of low and high current electron beams in dense plasma is simulated. Special emphasis is on peculiarities of its non-linear stages, such as filament formation and merger, saturation and post-saturation field and energy oscillations. *Supported by DOE Fusion Science through grant DE-FG02-05ER54840.

  16. Theory-based transport simulation of tokamaks: density scaling

    International Nuclear Information System (INIS)

    Ghanem, E.S.; Kinsey, J.; Singer, C.; Bateman, G.

    1992-01-01

    There has been a sizeable amount of work in the past few years using theoretically based flux-surface-average transport models to simulate various types of experimental tokamak data. Here we report two such studies, concentrating on the response of the plasma to variation of the line averaged electron density. The first study reported here uses a transport model described by Ghanem et al. to examine the response of global energy confinement time in ohmically heated discharges. The second study reported here uses a closely related and more recent transport model described by Bateman to examine the response of temperature profiles to changes in line-average density in neutral-beam-heated discharges. Work on developing a common theoretical model for these and other scaling experiments is in progress. (author) 5 refs., 2 figs

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

    International Nuclear Information System (INIS)

    Larson, J.D.

    1986-01-01

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

  18. Simulation of Particle Fluxes at the DESY-II Test Beam Facility

    International Nuclear Information System (INIS)

    Schuetz, Anne

    2015-05-01

    In the course of this Master's thesis ''Simulation of Particle Fluxes at the DESY-II Test Beam Facility'' the test beam generation for the DESY test beam line was studied in detail and simulated with the simulation software SLIC. SLIC uses the Geant4 toolkit for realistic Monte Carlo simulations of particles passing through detector material.After discussing the physics processes relevant for the test beam generation and the principles of the beam generation itself, the software used is introduced together with a description of the functionality of the Geant4 Monte Carlo simulation. The simulation of the test beam line follows the sequence of the test beam generation. Therefore, it starts with the simulation of the beam bunch of the synchrotron accelerator DESY-II, and proceeds step by step with the single test beam line components. An additional benefit of this thesis is the provision of particle flux and trajectory maps, which make fluxes directly visible by following the particle tracks through the simulated beam line. These maps allow us to see each of the test beam line components, because flux rates and directions change rapidly at these points. They will also guide the decision for placements of future test beam line components and measurement equipment.In the end, the beam energy and its spread, and the beam rate of the final test beam in the test beam area were studied in the simulation, so that the results can be compared to the measured beam parameters. The test beam simulation of this Master's thesis will serve as a key input for future test beam line improvements.

  19. High-Performance Beam Simulator for the LANSCE Linac

    International Nuclear Information System (INIS)

    Pang, Xiaoying; Rybarcyk, Lawrence J.; Baily, Scott A.

    2012-01-01

    A high performance multiparticle tracking simulator is currently under development at Los Alamos. The heart of the simulator is based upon the beam dynamics simulation algorithms of the PARMILA code, but implemented in C++ on Graphics Processing Unit (GPU) hardware using NVIDIA's CUDA platform. Linac operating set points are provided to the simulator via the EPICS control system so that changes of the real time linac parameters are tracked and the simulation results updated automatically. This simulator will provide valuable insight into the beam dynamics along a linac in pseudo real-time, especially where direct measurements of the beam properties do not exist. Details regarding the approach, benefits and performance are presented.

  20. High-current beam transport in electrostatic accelerator tubes

    International Nuclear Information System (INIS)

    Ramian, G.; Elais, L.

    1987-01-01

    The UCSB Free Electron Laser (FEL) has successfully demonstrated the use of a commercial 6 megavolt electrostatic accelerator as a high current beam source in a recirculating configuration. The accelerator, manufactured by National Electrostatics Corp. (NEC), Middleton WI, uses two standard high gradient accelerator tubes. Suppression of ion multiplication was accomplished by NEC with apertures and a shaped electrostatic field. This field shaping has fortuitously provided a periodically reversing radial field component with sufficient focusing strength to transport electron beams of up to 3 Amps current. Present two-stage FEL work requires a 20 Amp beam and proposed very high voltage FEL designs require currents as high as 100 Amps. A plan to permit transport of such high current beams by the addition of solenoidal focussing elements is described

  1. A simulation of heat transfer during billet transport

    Energy Technology Data Exchange (ETDEWEB)

    Jaklic, A.; Glogovac, B. [Institute of Metals and Technology, Ljubljana (Slovenia); Kolenko, T. [University of Ljubljana (Slovenia). Faculty of Natural Science and Technology; Zupancic, B. [University of Ljubljana (Slovenia). Faculty of Electrical Engineering; Zak, B. T. [Terming d.o.o., Ljubljana (Slovenia)

    2002-07-01

    This paper presents a simulation model for billet cooling during the billet's transport from the reheating furnace to the rolling mill. During the transport, the billet is exposed to radiation, convection and conduction. Due to the rectangular shape of the billet, the three-dimensional finite-difference model could be applied to calculate the heat conduction inside the billet. The billets are reheated in a gas-fired walking-beam furnace and are exposed to scaling. The model takes into account the effect of the thin oxide scale. We proved that the scale significantly affects the temperature distribution in the billet and should not be neglected. The model was verified by using a thermal camera. (author)

  2. Beam Simulations for IRE and Driver-Status and Strategy

    International Nuclear Information System (INIS)

    Friedman, A.; Grote, D.P.; Lee, E.P.; Sonnendrucker, E.

    2000-01-01

    The methods and codes employed in the U.S. Heavy Ion Fusion program to simulate the beams in an Integrated Research Experiments (IRE) facility and a fusion driver are presented in overview. A new family of models incorporating accelerating module impedance, multi-beam, and self-magnetic effects is described, and initial WARP3d particle simulations of beams using these models are presented. Finally, plans for streamlining the machine-design simulation sequence, and for simulating beam dynamics from the source to the target in a consistent and comprehensive manner, are described

  3. Documentation for TRACE: an interactive beam-transport code

    International Nuclear Information System (INIS)

    Crandall, K.R.; Rusthoi, D.P.

    1985-01-01

    TRACE is an interactive, first-order, beam-dynamics computer program. TRACE includes space-charge forces and mathematical models for a number of beamline elements not commonly found in beam-transport codes, such as permanent-magnet quadrupoles, rf quadrupoles, rf gaps, accelerator columns, and accelerator tanks. TRACE provides an immediate graphic display of calculative results, has a powerful and easy-to-use command procedure, includes eight different types of beam-matching or -fitting capabilities, and contains its own internal HELP package. This report describes the models and equations used for each of the transport elements, the fitting procedures, and the space-charge/emittance calculations, and provides detailed instruction for using the code

  4. Oxygen transport properties estimation by classical trajectory–direct simulation Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, Domenico, E-mail: domenico.bruno@cnr.it [Istituto di Metodologie Inorganiche e dei Plasmi, Consiglio Nazionale delle Ricerche– Via G. Amendola 122, 70125 Bari (Italy); Frezzotti, Aldo, E-mail: aldo.frezzotti@polimi.it; Ghiroldi, Gian Pietro, E-mail: gpghiro@gmail.com [Dipartimento di Scienze e Tecnologie Aerospaziali, Politecnico di Milano–Via La Masa 34, 20156 Milano (Italy)

    2015-05-15

    Coupling direct simulation Monte Carlo (DSMC) simulations with classical trajectory calculations is a powerful tool to improve predictive capabilities of computational dilute gas dynamics. The considerable increase in computational effort outlined in early applications of the method can be compensated by running simulations on massively parallel computers. In particular, Graphics Processing Unit acceleration has been found quite effective in reducing computing time of classical trajectory (CT)-DSMC simulations. The aim of the present work is to study dilute molecular oxygen flows by modeling binary collisions, in the rigid rotor approximation, through an accurate Potential Energy Surface (PES), obtained by molecular beams scattering. The PES accuracy is assessed by calculating molecular oxygen transport properties by different equilibrium and non-equilibrium CT-DSMC based simulations that provide close values of the transport properties. Comparisons with available experimental data are presented and discussed in the temperature range 300–900 K, where vibrational degrees of freedom are expected to play a limited (but not always negligible) role.

  5. Simulation of wire-compensation of long range beam beam interaction in high energy accelerators

    International Nuclear Information System (INIS)

    Dorda, U.; )

    2006-01-01

    Full text: We present weak-strong simulation results for the effect of long-range beam-beam (LRBB) interaction in LHC as well as for proposed wire compensation schemes or wire experiments, respectively. In particular, we discuss details of the simulation model, instability indicators, the effectiveness of compensation, the difference between nominal and PACMAN bunches for the LHC, beam experiments, and wire tolerances. The simulations are performed with the new code BBTrack. (author)

  6. Beam transport calculations for the EN tandem installation

    International Nuclear Information System (INIS)

    Sparks, R.J.

    1980-12-01

    Transport of a charged particle beam through the new EN tandem accelerator installation of the Institute of Nuclear Sciences has been analysed using simplified mathematical models. The purpose is to identify the factors affecting transmission of the beam, and to arrive at a design for the system to inject the beam into the accelerator

  7. Beam Dynamics Simulation for the CTF3 Drive Beam Accelerator

    CERN Document Server

    Schulte, Daniel

    2000-01-01

    A new CLIC Test Facility (CTF3) at CERN will serve to study the drive beam generation for the Compact Linear Collider (CLIC). CTF3 has to accelerate a 3.5 A electron beam in almost fully-loaded structures. The pulse contains more than 2000 bunches, one in every second RF bucket, and has a length of more than one microsecond. Different options for the lattice of the drive-beam accelerator are presented, based on FODO-cells and triplets as well as solenoids. The transverse stability is simulated, including the effects of beam jitter, alignment and beam-based correction.

  8. Ion transport studies on the PLT tokamak during neutral beam injection

    International Nuclear Information System (INIS)

    Suckewer, S.; Cavallo, A.; Cohen, S.

    1983-12-01

    Radial transport of ions during co- and counter-neutral beam heating in the PLT tokamak has been studied, using molybdenum and scandium ions as tracer elements. The time evolution of the radial profiles of several ionization stages of both elements, injected by laser blowoff during the neutral beam heating, were measured under three significantly different beam-plasma combinations. No noticeable differences in the radial profiles attributable to the beam direction were observed. However, a given injected amount resulted in considerably larger interior concentrations of the tracer element in the counter-beam heating cases, suggesting larger penetration of the plasma periphery. Computer simulation with the MIST code suggests a net inward drift of the order 10 3 cm/sec superposed to a diffusion coefficient of the order 10 4 cm 2 /sec for both scandium and molybdenum ions. Injection of larger amounts of the tracer element, sufficient to cause measurable central electron temperature changes, resulted in dramatic changes in ion-state distributions, making some appear peaked in the center while others disappeared. This effect could be produced with both co- and counter-beam heating, but with lesser amounts in the latter case. It is interpreted as rearrangement of the ionization balance, rather than any preferential accumulation of the injected element

  9. Resolving beam transport problems in electrostatic accelerators

    International Nuclear Information System (INIS)

    Larson, J.D.

    1977-01-01

    This paper reviews problem areas in beam transmission which are frequently encountered during the design, operation and upgrading of electrostatic accelerators. Examples are provided of analytic procedures that clarify accelerator ion optics and lead to more effective beam transport. Suggestions are made for evaluating accelerator design with the goal of improved performance

  10. EBQ code: Transport of space-charge beams in axially symmetric devices

    Science.gov (United States)

    Paul, A. C.

    1982-11-01

    Such general-purpose space charge codes as EGUN, BATES, WODF, and TRANSPORT do not gracefully accommodate the simulation of relativistic space-charged beams propagating a long distance in axially symmetric devices where a high degree of cancellation has occurred between the self-magnetic and self-electric forces of the beam. The EBQ code was written specifically to follow high current beam particles where space charge is important in long distance flight in axially symmetric machines possessing external electric and magnetic field. EBQ simultaneously tracks all trajectories so as to allow procedures for charge deposition based on inter-ray separations. The orbits are treated in Cartesian geometry (position and momentum) with z as the independent variable. Poisson's equation is solved in cylindrical geometry on an orthogonal rectangular mesh. EBQ can also handle problems involving multiple ion species where the space charge from each must be included. Such problems arise in the design of ion sources where different charge and mass states are present.

  11. EBQ code: transport of space-charge beams in axially symmetric devices

    International Nuclear Information System (INIS)

    Paul, A.C.

    1982-11-01

    Such general-purpose space charge codes as EGUN, BATES, WOLF, and TRANSPORT do not gracefully accommodate the simulation of relativistic space-charged beams propagating a long distance in axially symmetric devices where a high degree of cancellation has occurred between the self-magnetic and self-electric forces of the beam. The EBQ code was written specifically to follow high current beam particles where space charge is important in long distance flight in axially symmetric machines possessing external electric and magnetic field. EBQ simultaneously tracks all trajectories so as to allow procedures for charge deposition based on inter-ray separations. The orbits are treated in Cartesian geometry (position and momentum) with z as the independent variable. Poisson's equation is solved in cylindrical geometry on an orthogonal rectangular mesh. EBQ can also handle problems involving multiple ion species where the space charge from each must be included. Such problems arise in the design of ion sources where different charge and mass states are present

  12. Monte-Carlo simulation of complex vapor-transport systems for RIB applications

    International Nuclear Information System (INIS)

    Zhang, Y.; Alton, G.D.

    2005-01-01

    In order to minimize decay losses of short-lived radioactive species at ISOL based RIB facilities, effusive-flow particle transit times between target and ion source must be as short as practically achievable. A Monte-Carlo code has been developed for simulating the effusive-flow of neutral particles through vapor-transport systems independent of materials of construction. The code provides average distance traveled and time information associated with the transit of individual particles through a system. It offers a cost effective and accurate means for arriving at vapor-transport system designs. In this report, the code will be described and results obtained by its use in evaluating several prototype vapor-transport systems using specular reflection, cosine and isotropic particle re-emission about the normal to the surface models following adsorption. Simulation results obtained with an isotropic distribution are in close agreement with experimental measurements of the properties of prototype vapor-transport systems fabricated at the Holifield Radioactive Ion Beam Facility

  13. Resolving beam transport problems in electrostatic accelerators

    International Nuclear Information System (INIS)

    Larson, J.D.

    1977-01-01

    A review is given of problem areas in beam transmission which are frequently encountered during the design, operation and upgrading of electrostatic accelerators. Examples are provided of analytic procedures that clarify accelerator ion optics and lead to more effective beam transport. Suggestions are made for evaluating accelerator design with the goal of improved performance

  14. Beam transport optics for high-power laser systems

    International Nuclear Information System (INIS)

    Taylor, J.R.

    1995-01-01

    Beam transport optics receive output energy from the laser cavity and deliver it to the work site. Depending on the application, this may require a few simple elements or large complex systems. Collection of the laser energy depends on the spatial and temporal energy distribution as well as the wavelength and polarization of the laser cavity and output coupler. Transport optics can perform a variety of functions, including beam formatting, frequency doubling, and distribution to one or more work sites while maintaining or even improving the beam quality. The beam may be delivered to work sites as focused spots or images, projected to distant targets, or propagated through various media for sensing or photochemical processing. Design may involve optical modeling of the system, including diffraction effects and thermal management. A Gaussian beam profile is often used for convenience in modeling. When deviations from this ideal profile need to be considered, it is necessary to characterize the laser beam in detail. Design of the transport system requires understanding of the interaction of the laser energy with optical materials and components. Practical considerations include mounting the optics without stress and with the stability suitable for the intended application. Requirements for beam direction, stability, size, shape, and quality dictate the design approach for each specific situation. Attention also must be given to reliability, environmental, and commercial requirements. Damage to optics in high-power laser systems is a common concern. Environmental problems such as atmospheric turbulence, contamination by dust or vapor from the work site or other sources, or absorption of water vapor can directly degrade beam quality. Other potentially significant optical performance effects may result from instability and aging of the optics, temperature, humidity, pressure, transmitted vibration, and contamination from the work site or other sources

  15. Compact electrostatic beam optics for multi-element focused ion beams: simulation and experiments.

    Science.gov (United States)

    Mathew, Jose V; Bhattacharjee, Sudeep

    2011-01-01

    Electrostatic beam optics for a multi-element focused ion beam (MEFIB) system comprising of a microwave multicusp plasma (ion) source is designed with the help of two widely known and commercially available beam simulation codes: AXCEL-INP and SIMION. The input parameters to the simulations are obtained from experiments carried out in the system. A single and a double Einzel lens system (ELS) with and without beam limiting apertures (S) have been investigated. For a 1 mm beam at the plasma electrode aperture, the rms emittance of the focused ion beam is found to reduce from ∼0.9 mm mrad for single ELS to ∼0.5 mm mrad for a double ELS, when S of 0.5 mm aperture size is employed. The emittance can be further improved to ∼0.1 mm mrad by maintaining S at ground potential, leading to reduction in beam spot size (∼10 μm). The double ELS design is optimized for different electrode geometrical parameters with tolerances of ±1 mm in electrode thickness, electrode aperture, inter electrode distance, and ±1° in electrode angle, providing a robust design. Experimental results obtained with the double ELS for the focused beam current and spot size, agree reasonably well with the simulations.

  16. Experimental simulations of beam propagation over large distances in a compact linear Paul trap

    International Nuclear Information System (INIS)

    Gilson, Erik P.; Chung, Moses; Davidson, Ronald C.; Dorf, Mikhail; Efthimion, Philip C.; Majeski, Richard

    2006-01-01

    The Paul Trap Simulator Experiment (PTSX) is a compact laboratory experiment that places the physicist in the frame of reference of a long, charged-particle bunch coasting through a kilometers-long magnetic alternating-gradient (AG) transport system. The transverse dynamics of particles in both systems are described by similar equations, including nonlinear space-charge effects. The time-dependent voltages applied to the PTSX quadrupole electrodes are equivalent to the axially oscillating magnetic fields applied in the AG system. Experiments concerning the quiescent propagation of intense beams over large distances can then be performed in a compact and flexible facility. An understanding and characterization of the conditions required for quiescent beam transport, minimum halo particle generation, and precise beam compression and manipulation techniques, are essential, as accelerators and transport systems demand that ever-increasing amounts of space charge be transported. Application areas include ion-beam-driven high energy density physics, high energy and nuclear physics accelerator systems, etc. One-component cesium plasmas have been trapped in PTSX that correspond to normalized beam intensities, s=ω p 2 (0)/2ω q 2 , up to 80% of the space-charge limit where self-electric forces balance the applied focusing force. Here, ω p (0)=[n b (0)e b 2 /m b ε 0 ] 1/2 is the on-axis plasma frequency, and ω q is the smooth-focusing frequency associated with the applied focusing field. Plasmas in PTSX with values of s that are 20% of the limit have been trapped for times corresponding to equivalent beam propagation over 10 km. Results are presented for experiments in which the amplitude of the quadrupole focusing lattice is modified as a function of time. It is found that instantaneous changes in lattice amplitude can be detrimental to transverse confinement of the charge bunch

  17. Experimental simulations of beam propagation over large distances in a compact linear Paul trapa)

    Science.gov (United States)

    Gilson, Erik P.; Chung, Moses; Davidson, Ronald C.; Dorf, Mikhail; Efthimion, Philip C.; Majeski, Richard

    2006-05-01

    The Paul Trap Simulator Experiment (PTSX) is a compact laboratory experiment that places the physicist in the frame of reference of a long, charged-particle bunch coasting through a kilometers-long magnetic alternating-gradient (AG) transport system. The transverse dynamics of particles in both systems are described by similar equations, including nonlinear space-charge effects. The time-dependent voltages applied to the PTSX quadrupole electrodes are equivalent to the axially oscillating magnetic fields applied in the AG system. Experiments concerning the quiescent propagation of intense beams over large distances can then be performed in a compact and flexible facility. An understanding and characterization of the conditions required for quiescent beam transport, minimum halo particle generation, and precise beam compression and manipulation techniques, are essential, as accelerators and transport systems demand that ever-increasing amounts of space charge be transported. Application areas include ion-beam-driven high energy density physics, high energy and nuclear physics accelerator systems, etc. One-component cesium plasmas have been trapped in PTSX that correspond to normalized beam intensities, ŝ=ωp2(0)/2ωq2, up to 80% of the space-charge limit where self-electric forces balance the applied focusing force. Here, ωp(0)=[nb(0)eb2/mbɛ0]1/2 is the on-axis plasma frequency, and ωq is the smooth-focusing frequency associated with the applied focusing field. Plasmas in PTSX with values of ŝ that are 20% of the limit have been trapped for times corresponding to equivalent beam propagation over 10km. Results are presented for experiments in which the amplitude of the quadrupole focusing lattice is modified as a function of time. It is found that instantaneous changes in lattice amplitude can be detrimental to transverse confinement of the charge bunch.

  18. SLC injector simulation and tuning for high charge transport

    International Nuclear Information System (INIS)

    Yeremian, A.D.; Miller, R.H.; Clendenin, J.E.; Early, R.A.; Ross, M.C.; Turner, J.L.; Wang, J.W.

    1992-01-01

    We have simulated the SLC injector from the thermionic gun through the first accelerating section and used the resulting parameters to tune the injector for optimum performance and high charge transport. Simulations are conducted using PARMELA, a three-dimensional space-charge model. The magnetic field profile due to the existing magnetic optics is calculated using POISSON, while SUPERFISH is used to calculate the space harmonics of the various bunchers and the accelerator cavities. The initial beam conditions in the PARMELA code are derived from the EGUN model of the gun. The resulting injector parameters from the PARMELA simulation are used to prescribe experimental settings of the injector components. The experimental results are in agreement with the results of the integrated injector model. (Author) 5 figs., 7 refs

  19. Intense heavy-ion beam transport with electric and magnetic quadrupoles

    International Nuclear Information System (INIS)

    Fessenden, T.J.; Hopkins, H.S.

    1995-08-01

    As part of the small induction recirculator development at LLNL, the authors are testing an injector and transport line that delivers 4 micros beams of potassium with repetition rates up to 10 Hz at a nominal current of 2 mA. The normalized K-V equivalent emittance of the beams is near 0.02 π mm-mrad and is mostly determined by the temperature of the source (0.1 eV). K + ions generated at 80 keV in a Pierce diode are matched to an alternating gradient transport line by seven electric quadrupoles. Two additional quads have been modified to serve as two-axis steerers. The matching section is followed by a transport section comprised of seven permanent magnet quadrupoles. Matching to this section is achieved by adjusting the voltages on the electric quadrupoles to voltages calculated by an envelope matching code. Measurements of beam envelope parameters are made at the matching section entrance and exit as well as at the end of the permanent magnet transport section. Beam current waveforms along the experiment are compared with results from a one-dimension longitudinal dynamics code. Initial experiments show particle loss occurring at the beam head as a result of overtaking. The apparatus is also being used for the development of non or minimally intercepting diagnostics for future recirculator experiments. These include capacitive monitors for determining beam line-charge density and position in the recirculator; flying wire scanners for beam position; and gated TV scanners for measuring beam profiles and emittance

  20. Time domain simulations of beam-loading

    International Nuclear Information System (INIS)

    Koscielniak, S.

    1989-09-01

    We present the results of computer simulations of high current beam loading in a proton storage ring. The model integrates the differential equation for gap voltage, and iterates the difference equations for particle longitudinal motion. The effects of cavity fields on the bunch shape and of the fundamental component of the beam on the cavity are treated in a self-consistent manner. The simulation model is applied to verify the dipole-quadrupole hybrid Robinson instability criterion, which differs from the dipole-mode criterion

  1. Large Scale Beam-beam Simulations for the CERN LHC using Distributed Computing

    CERN Document Server

    Herr, Werner; McIntosh, E; Schmidt, F

    2006-01-01

    We report on a large scale simulation of beam-beam effects for the CERN Large Hadron Collider (LHC). The stability of particles which experience head-on and long-range beam-beam effects was investigated for different optical configurations and machine imperfections. To cover the interesting parameter space required computing resources not available at CERN. The necessary resources were available in the LHC@home project, based on the BOINC platform. At present, this project makes more than 60000 hosts available for distributed computing. We shall discuss our experience using this system during a simulation campaign of more than six months and describe the tools and procedures necessary to ensure consistent results. The results from this extended study are presented and future plans are discussed.

  2. Evaluation of the BEAM--BEAM effect in PEP using Myer's simulation program

    International Nuclear Information System (INIS)

    Hutton, A.

    1982-09-01

    The program BEAM BEAM written by Steve Myers for the LEP machine at CERN has given encouraging results in the simulation of the beam-beam effect in electron-positron storage rings. It therefore seemed worthwhile to apply the program to PEP with two main intentions. Firstly, to confirm the validity of the program by comparison with experimental data from previous PEP runs and secondly, to search for an improvement in the operating conditions of PEP. Clearly a successful prediction would also enhance the credibility of the program. The program itself has been extensively described in the literature and will not be repeated here, except for some comments of direct relevance to the present simulation. 14 refs., 15 figs., 4 tabs

  3. LSST beam simulator

    International Nuclear Information System (INIS)

    Tyson, J A; Klint, M; Sasian, J; Claver, C; Muller, G; Gilmor, K

    2014-01-01

    It is always important to test new imagers for a mosaic camera before device acceptance and constructing the mosaic. This is particularly true of the LSST CCDs due to the fast beam illumination: at long wavelengths there can be significant beam divergence (defocus) inside the silicon because of the long absorption length for photons near the band gap. Moreover, realistic sky scenes need to be projected onto the CCD focal plane Thus, we need to design and build an f/1.2 re-imaging system. The system must simulate the entire LSST 1 operation, including a sky with galaxies and stars with approximately black-body spectra superimposed on a spatially diffuse night sky emission with its complex spectral features

  4. Beam transport of PF (Positron Factory) 2.5-GeV linac

    International Nuclear Information System (INIS)

    Shiraga, Takahiro; Asami, Akira; Suwada, Tsuyoshi; Kobayashi, Hitoshi.

    1993-01-01

    The beam transport is one of the most important problems in the linac to be used as the injector for the B-FACTORY accelerators. A basic problem of the beam transport is how to correct transport parameters immediately when a klystron becomes off. This is studied with the PF (Positron Factory) 2.5-GeV linac. (author)

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

    International Nuclear Information System (INIS)

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

    1998-01-01

    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 - 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 βλ structure to a CCDTL operated at 805 MHz with a 12 βλ 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

  6. Simulation based analysis of laser beam brazing

    Science.gov (United States)

    Dobler, Michael; Wiethop, Philipp; Schmid, Daniel; Schmidt, Michael

    2016-03-01

    Laser beam brazing is a well-established joining technology in car body manufacturing with main applications in the joining of divided tailgates and the joining of roof and side panels. A key advantage of laser brazed joints is the seam's visual quality which satisfies highest requirements. However, the laser beam brazing process is very complex and process dynamics are only partially understood. In order to gain deeper knowledge of the laser beam brazing process, to determine optimal process parameters and to test process variants, a transient three-dimensional simulation model of laser beam brazing is developed. This model takes into account energy input, heat transfer as well as fluid and wetting dynamics that lead to the formation of the brazing seam. A validation of the simulation model is performed by metallographic analysis and thermocouple measurements for different parameter sets of the brazing process. These results show that the multi-physical simulation model not only can be used to gain insight into the laser brazing process but also offers the possibility of process optimization in industrial applications. The model's capabilities in determining optimal process parameters are exemplarily shown for the laser power. Small deviations in the energy input can affect the brazing results significantly. Therefore, the simulation model is used to analyze the effect of the lateral laser beam position on the energy input and the resulting brazing seam.

  7. Interfacing MCNPX and McStas for simulation of neutron transport

    DEFF Research Database (Denmark)

    Klinkby, Esben Bryndt; Lauritzen, Bent; Nonbøl, Erik

    2013-01-01

    Stas[4, 5, 6, 7]. The coupling between the two simulation suites typically consists of providing analytical fits of MCNPX neutron spectra to McStas. This method is generally successful but has limitations, as it e.g. does not allow for re-entry of neutrons into the MCNPX regime. Previous work to resolve......Simulations of target-moderator-reflector system at spallation sources are conventionally carried out using Monte Carlo codes such as MCNPX[1] or FLUKA[2, 3] whereas simulations of neutron transport from the moderator and the instrument response are performed by neutron ray tracing codes such as Mc...... geometries, backgrounds, interference between beam-lines as well as shielding requirements along the neutron guides....

  8. Beam diagnostics and data acquisition system for ion beam transport line used in applied research

    International Nuclear Information System (INIS)

    Skuratov, V.A.; Didyk, A.Yu.; Arkhipov, A.V.; Illes, A.; Bodnar, K.; Illes, Z.; Havancsak, K.

    1999-01-01

    Ion beam transport line for applied research on U-400 cyclotron, beam diagnostics and data acquisition system for condensed matter studies are described. The main features of Windows-based real time program are considered

  9. Impurity ion transport studies on the PLT tokamak during neutral-beam injection

    International Nuclear Information System (INIS)

    Suckewer, S.; Cavallo, A.; Cohen, S.

    1984-01-01

    Radial transport of medium- and high-Z ions during co- and counter-neutral-beam heating in the PLT tokamak is studied, using molybdenum and scandium ions as tracer elements. The time evolution of the radial profiles of several ionization stages of both elements, injected by laser blowoff during the neutral-beam heating, is measured under three significantly different beam-plasma combinations. No noticeable differences in the radial profiles attributable to the beam direction are observed. However, a given injected amount resulted in considerably larger interior concentrations of the tracer element in the counter-beam heating cases, suggesting larger penetration of the plasma periphery. Computer simulation with the MIST code suggests a net inward drift of the order 10 3 cm.s -1 superposed to a diffusion coefficient of the order 10 4 cm 2 .s -1 for both scandium and molybdenum ions. Injection of larger amounts of the tracer element, sufficient to cause measurable central electron temperature changes, resulted in dramatic changes in ion-state distributions, making some appear peaked in the centre while others disappeared. This effect could be produced with both co- and counter-beam heating, but with lesser amounts in the latter case. It is interpreted as rearrangement of the ionization balance, rather than any preferential accumulation of the injected element. (author)

  10. On Start to End Simulation and Modeling Issues of the Megawatt Proton Beam Facility at PSI

    CERN Document Server

    Adelmann, Andreas; Fitze, Hansruedi; Geus, Roman; Humbel, Martin; Stingelin, Lukas

    2005-01-01

    At the Paul Scherrer Institut (PSI) we routinely extract a one megawatt (CW) proton beam out of our 590 MeV Ring Cyclotron. In the frame of the ongoing upgrade program, large scale simulations have been undertaken in order to provide a sound basis to assess the behaviour of very intense beams in cyclotrons. The challenges and attempts towards massive parallel three dimensional start-to- end simulations will be discussed. The used state of the art numerical tools (mapping techniques, time integration, parallel FFT and finite element based multigrid Poisson solver) and their parallel implementation will be discussed. Results will be presented in the area of: space charge dominated beam transport including neighbouring turns, eigenmode analysis to obtain accurate electromagnetic fields in large the rf cavities and higher order mode interaction between the electromagnetic fields and the particle beam. For the problems investigated so far a good agreement between theory i.e. calculations and measurements is obtain...

  11. Time dependence of microsecond intense electron beam transport in gases

    International Nuclear Information System (INIS)

    Lucey, R.F. Jr.; Gilgenback, R.M.; Tucker, J.E.; Brake, M.L.; Enloe, C.L.; Repetti, T.E.

    1987-01-01

    The authors present results of long-pulse (0.5 μs) electron beam propagation in the ion focused regime (IFR). Electron beam parameters are 800 kV with several hundred amperes injected current. For injection into air (from 0.7 mTorr to 75 mTorr) and helium (from 14 mTorr to 227 mTorr) the authors observe a ''time-dependent propagation window'' in which efficient (up to 100%) propagation starts at a time comparable to the electron impact ionization time needed to achieve n/sub i/ -- (1/γ/sup 2/)n/sub eb/. The transport goes abruptly to zero about 50-150 ns after this initial propagation. This is followed by erratic propagation often consisting of numerous narrower pulses 10-40 ns wide. In these pulses the transported current can be 100% of the injected current, but is generally lower. As the fill pressure is increased, there are differences in the propagated beam pulse, which can be summarized as follows: 1) the temporal occurrence of the beam propagation window shifts to earlier times, 2) the propagated beam current has much faster risetimes, 3) a larger portion of the injected beam is propagated. Similar results are observed when the electron beam is propagated in helium. However, at a given pressure, the beam transport window occurs at later times and exhibits a slower risetime. These effects are consistent with electron beam-induced ionization. Experiments are being performed to determine if the observed beam instability is due to the ion hose instability or streaming instability

  12. SLC injector simulation and tuning for high charge transport

    International Nuclear Information System (INIS)

    Yeremian, A.D.; Miller, R.H.; Clendenin, J.E.; Early, R.A.; Ross, M.C.; Turner, J.L.; Wang, J.W.

    1992-08-01

    We have simulated the SLC injector from the thermionic gun through the first accelerating section and used the resulting parameters to tune the injector for optimum performance and high charge transport. Simulations are conducted using PARMELA, a three-dimensional ray-trace code with a two-dimensional space-charge model. The magnetic field profile due to the existing magnetic optics is calculated using POISSON, while SUPERFISH is used to calculate the space harmonics of the various bunchers and the accelerator cavities. The initial beam conditions in the PARMELA code are derived from the EGUN model of the gun. The resulting injector parameters from the PARMELA simulation are used to prescribe experimental settings of the injector components. The experimental results are in agreement with the results of the integrated injector model

  13. Simulation of ion beam scattering in a gas stripper

    Energy Technology Data Exchange (ETDEWEB)

    Maxeiner, Sascha, E-mail: maxeiner@phys.ethz.ch; Suter, Martin; Christl, Marcus; Synal, Hans-Arno

    2015-10-15

    Ion beam scattering in the gas stripper of an accelerator mass spectrometer (AMS) enlarges the beam phase space and broadens its energy distribution. As the size of the injected beam depends on the acceleration voltage through phase space compression, the stripper becomes a limiting factor of the overall system transmission especially for low energy AMS system in the sub MV region. The spatial beam broadening and collisions with the accelerator tube walls are a possible source for machine background and energy loss fluctuations influence the mass resolution and thus isotope separation. To investigate the physical processes responsible for these effects, a computer simulation approach was chosen. Monte Carlo simulation methods are applied to simulate elastic two body scattering processes in screened Coulomb potentials in a (gas) stripper and formulas are derived to correctly determine random collision parameters and free path lengths for arbitrary (and non-homogeneous) gas densities. A simple parametric form for the underlying scattering cross sections is discussed which features important scaling behaviors. An implementation of the simulation was able to correctly model the data gained with the TANDY AMS system at ETH Zurich. The experiment covered transmission measurements of uranium ions in helium and beam profile measurements after the ion beam passed through the He-stripper. Beam profiles measured up to very high stripper densities could be understood in full system simulations including the relevant ion optics. The presented model therefore simulates the fundamental physics of the interaction between an ion beam and a gas stripper reliably. It provides a powerful and flexible tool for optimizing existing AMS stripper geometries and for designing new, state of the art low energy AMS systems.

  14. High-current beam dynamics and transport, theory and experiment

    International Nuclear Information System (INIS)

    Reiser, M.

    1986-01-01

    Recent progress in the understanding of beam physics and technology factors determining the current and brightness of ion and electron beams in linear accelerators will be reviewed. Topics to be discussed including phase-space density constraints of particle sources, low-energy beam transport include charge neutralization, emittance growth due to mismatch, energy exchange, instabilities, nonlinear effects, and longitudinal bunching

  15. Channel-accelerating gap interaction and beam acceleration and transport experiments with the recirculating linear accelerator (RLA)

    International Nuclear Information System (INIS)

    Mazarakis, M.G.; Smith, D.L.; Poukey, J.W.; Wagner, J.S.; Bennett, L.F.; Olson, W.R.; Turman, B.N.; Prestwich, K.R.; Wells, J.; Struve, K.

    1992-01-01

    The lifetime of the Ion Focusing Regime (IFR) channel following the pulsing of the post-accelerating gaps is critical for open-ended low energy devices. It dictates the number of allowable beam recirculations through the gaps. In the case of a closed racetrack configuration, it is significant but not as critical, since the presence of the electron beam focuses the ions and lengthens the lifetime of the ion channel. The authors have experimentally established that pulsing an accelerating gap perturbs the IFR channel. However for the parameters studied, the lifetime is long enough to allow at least four beam recirculations in a spiral device. In addition transparent grids of cusp fields positioned upstream and downstream from the gaps prevent them from perturbing the IFR channel. Experiments were performed with and without injected electron beams. For the experiments investigating the IFR channel interaction with the accelerating gap, the injector was removed and the beam line was extended downstream and upstream from the accelerating cavity. Only the first straight section of the RLA with one accelerating cavity (ET-2) was utilized. The acceleration and transport experiments were performed utilizing two injectors: first the low energy 1.3-MV Isolated Blumlein (IB) injector and most recently the new 4-MV 20-kA injector. Beams of 6--20 kA current were produced and successfully transported and accelerated through the ET-2 post-accelerating gap. For both injectors an apertured non-immersed ion-focused foilless diode was selected among various options. It is the simplest and easiest to operate and can be adjusted to provide variable beam impedance loads to the injector. The transport efficiencies were 90% for the low energy injector and 100% for the new 4-MV injector. The beam Gaussian profile and radius (5 mm) remain the same through acceleration. Experimental results will be presented and compared with numerical simulations

  16. Three dimensional simulations of space charge dominated heavy ion beams with applications to inertial fusion energy

    International Nuclear Information System (INIS)

    Grote, D.P.

    1994-01-01

    Heavy ion fusion requires injection, transport and acceleration of high current beams. Detailed simulation of such beams requires fully self-consistent space charge fields and three dimensions. WARP3D, developed for this purpose, is a particle-in-cell plasma simulation code optimized to work within the framework of an accelerator's lattice of accelerating, focusing, and bending elements. The code has been used to study several test problems and for simulations and design of experiments. Two applications are drift compression experiments on the MBE-4 facility at LBL and design of the electrostatic quadrupole injector for the proposed ILSE facility. With aggressive drift compression on MBE-4, anomalous emittance growth was observed. Simulations carried out to examine possible causes showed that essentially all the emittance growth is result of external forces on the beam and not of internal beam space-charge fields. Dominant external forces are the dodecapole component of focusing fields, the image forces on the surrounding pipe and conductors, and the octopole fields that result from the structure of the quadrupole focusing elements. Goal of the design of the electrostatic quadrupole injector is to produce a beam of as low emittance as possible. The simulations show that the dominant effects that increase the emittance are the nonlinear octopole fields and the energy effect (fields in the axial direction that are off-axis). Injectors were designed that minimized the beam envelope in order to reduce the effect of the nonlinear fields. Alterations to the quadrupole structure that reduce the nonlinear fields further were examined. Comparisons were done with a scaled experiment resulted in very good agreement

  17. Experimental study and simulation of the extraction conditions of a multicharged ion beam from an electron cyclotron resonance source

    International Nuclear Information System (INIS)

    Mandin, J.

    1996-01-01

    This thesis concerns the beam extraction studies of ECR Ion Sources for the SPIRAL project at GANIL (France). The optical properties (i.e. the emittances) of the radioactive ion beam production source is a crucial point in this project. We performed emittance measurements with a very high transport efficiency and developed a computer code for simulating the extraction and transport conditions. This simulation takes into account all the parameters acting on the extraction process: the characteristics of the ions and electrons emitted by the plasma, their space and energy distributions, the space charge, the magnetic filed of the source and the accelerating electric field. We explained the evolution of the emittances for two different types of ECR Ion Source. The simulation-experiment comparison showed us that the magnetic field and the intrinsic energy of the ions seem to be the most important parameters for explaining the overall emittance behaviour of the ECRIS. We precise their values and comment them. (author)

  18. Characteristics of Far Transported Laser Beam

    Energy Technology Data Exchange (ETDEWEB)

    Park, Dae Yoon; Kim, Ki Sik; Lee, Seung Gol [Inha University, Inchon (Korea, Republic of)

    1997-07-01

    A beam propagating in free space or in a medium generally experiences diffraction, and hence it suffers an energy loss and an wavefront distortion. It Is essential for a stable and precise communication to eliminate or to minimize the diffraction effect accompanying on propagation. The diffraction-free beam is introduced for that purpose. A typical diffraction-free beam is the Bessel beam. The Bessel beam has, however, an infinite energy in the cross-section perpendicular to the direction of propagation and, because of this fact, its realizability is sceptical. To remedy this problem, a new beam is introduced, which has a series from with a Gaussian envelope function and tested for diffraction on propagation by a computer simulation. Compared with the Bessel-Gauss beam, this new beam shows much less diffraction. While, by using a scraper mirror in an Nd:YAG laser with a ring resonator, an annular output beam is obtained. This annular beam is focused by a Fourier Transformation lens to produce a diffraction-free beam. This diffraction-free beam dose not show any noticible diffraction on propagation over the distance of 16 m, which is determined by the scraper mirror and the Fourier transformation lens. This achievement provides a profound basis for the generation of diffraction-free beams over much longer distances. The developed technique will provide a stable and precise communication method in remote controlling system, remote sensing through atmosphere, and information transfer using the optical fiber. 30 refs., 22 figs. (author)

  19. Calculation of channels for forming and transport of medical proton beams at the JINR phasotron

    International Nuclear Information System (INIS)

    Kuz'min, E.S.; Mirokhin, I.V.; Molokanov, A.G.; Obukhov, Yu.L.; Savchenko, O.V.

    1984-01-01

    Results of numerical simulation of shaping and transporting processes of therapeutic proton beams with a modified Bragg curve at the JINR phasotron are presented. The mean energy of proton beams are about 100, 130 and 200 MeV. To provide the flat-topped depth-dose distributions with a steep back slope, the method of shaping with a necessary energy spectrum from a nonmonoenergetic beam is used. It is shown by the calculations that it is possible to choose such modes of the channel operation at which clinical-physical requirements to the parameters of medical proton beams are satisfied. Extensions of flat-tops of dose peaks are 1.3 g/cm 2 , 1.7 g/cm 2 and 3.5 g/cm 2 for the 100 MeV, 130 MeV and 200 MeV beam energies, respectively. Dose rate in the peaks of modified distributions are not less than 100 rad per minute

  20. Beam-Beam Simulation of Crab Cavity White Noise for LHC Upgrade

    CERN Document Server

    Qiang, J; Pieloni, Tatiana; Ohmi, Kazuhito

    2015-01-01

    High luminosity LHC upgrade will improve the luminosity of the current LHC operation by an order of magnitude. Crab cavity as a critical component for compensating luminosity loss from large crossing angle collision and also providing luminosity leveling for the LHC upgrade is being actively pursued. In this paper, we will report on the study of potential effects of the crab cavity white noise errors on the beam luminosity lifetime based on strong-strong beam-beam simulations.

  1. Simulation and Measurements of Beam Losses on LHC Collimators During Beam Abort Failures

    CERN Document Server

    Lari, L; Bruce, R; Goddard, B; Redaelli, S; Salvachua, B; Valentino, G; Faus-Golfe, A

    2013-01-01

    One of the main purposes of tracking simulations for collimation studies is to produce loss maps along the LHC ring, in order to identify the level of local beam losses during nominal and abnormal operation scenarios. The SixTrack program is the standard tracking tool used at CERN to perform these studies. Recently, it was expanded in order to evaluate the proton load on different collimators in case of fast beam failures. Simulations are compared with beam measurements at 4 TeV. Combined failures are assumed which provide worst-case scenarios of the load on tungsten tertiary collimators.

  2. Formation of an intense proton beam of microsecond duration

    Energy Technology Data Exchange (ETDEWEB)

    Engelko, V [Efremov Inst. of Electrophysical Apparatus, St. Petersburg (Russian Federation); Giese, H; Schalk, S [Forschungszentrum Karlsruhe (Germany)

    1997-12-31

    The proton beam facility PROFA serves as a test installation for ion source development and beam transport optimization for an intense pulsed proton beam of low kinetic energy, envisaged for ITER divertor load simulation. The present state of the investigations is discussed with emphasis on the diode operation parameters, beam divergence and beam transport efficiency. (author). 7 figs., 5 refs.

  3. Transport and dosimetric solutions for the ELIMED laser-driven beam line

    Energy Technology Data Exchange (ETDEWEB)

    Cirrone, G.A.P. [INFN-LNS, Via S. Sofia 62 - 95125 Catania (Italy); Romano, F. [INFN-LNS, Via S. Sofia 62 - 95125 Catania (Italy); Medical Physics School, University of Catania, Via S. Sofia 64 - 95125 Catania (Italy); Scuderi, V. [INFN-LNS, Via S. Sofia 62 - 95125 Catania (Italy); Institute of Physics ASCR, v.v.i. (FZU), ELI-Beamlines Project, Na Slovance 2, 182 21 Prague (Czech Republic); Amato, A. [INFN-LNS, Via S. Sofia 62 - 95125 Catania (Italy); Candiano, G. [INFN-LNS, Via S. Sofia 62 - 95125 Catania (Italy); Medical Physics School, University of Catania, Via S. Sofia 64 - 95125 Catania (Italy); Cuttone, G. [INFN-LNS, Via S. Sofia 62 - 95125 Catania (Italy); Giove, D. [INFN Sezione di Milano, Via Celoria 16, Milano (Italy); Korn, G.; Krasa, J. [Institute of Physics ASCR, v.v.i. (FZU), ELI-Beamlines Project, Na Slovance 2, 182 21 Prague (Czech Republic); Leanza, R. [INFN-LNS, Via S. Sofia 62 - 95125 Catania (Italy); Universitá degli Studi di Catania, Dipartimento di Fisica e Astronomia, Via S. Sofia 64, Catania (Italy); Manna, R. [INFN-LNS, Via S. Sofia 62 - 95125 Catania (Italy); Maggiore, M. [INFN-LNL, Viale dell' Universitá 2 - 35020 Legnaro (PD) (Italy); Marchese, V. [INFN-LNS, Via S. Sofia 62 - 95125 Catania (Italy); Margarone, D. [Institute of Physics ASCR, v.v.i. (FZU), ELI-Beamlines Project, Na Slovance 2, 182 21 Prague (Czech Republic); Milluzzo, G. [INFN-LNS, Via S. Sofia 62 - 95125 Catania (Italy); Universitá degli Studi di Catania, Dipartimento di Fisica e Astronomia, Via S. Sofia 64, Catania (Italy); Petringa, G. [INFN-LNS, Via S. Sofia 62 - 95125 Catania (Italy); Sabini, M.G. [INFN-LNS, Via S. Sofia 62 - 95125 Catania (Italy); Azienda Ospedaliera Cannizzaro, Via Messina 829 - 95100 Catania (Italy); Schillaci, F. [INFN-LNS, Via S. Sofia 62 - 95125 Catania (Italy); Medical Physics School, University of Catania, Via S. Sofia 64 - 95125 Catania (Italy); and others

    2015-10-01

    Within 2017, the ELIMED (ELI-Beamlines MEDical applications) transport beam-line and dosimetric systems for laser-generated beams will be installed at the ELI-Beamlines facility in Prague (CZ), inside the ELIMAIA (ELI Multidisciplinary Applications of laser–Ion Acceleration) interaction room. The beam-line will be composed of two sections: one in vacuum, devoted to the collecting, focusing and energy selection of the primary beam and the second in air, where the ELIMED beam-line dosimetric devices will be located. This paper briefly describes the transport solutions that will be adopted together with the main dosimetric approaches. In particular, the description of an innovative Faraday Cup detector with its preliminary experimental tests will be reported.

  4. Beam dynamics calculations for the linac booster beam line

    International Nuclear Information System (INIS)

    Lu, J.Q.; Cramer, J.G.; Storm, D.W.

    1987-01-01

    Beam optics focusing characteristics both in the transverse and longitudinal directions of the superconducting linac booster beam line are calculated for different particles. Three computer programs, which are TRANSPORT, LYRA and ENTIME, are used to simulate particle motions. The first one is used to simulate the particle radial motions. The effects of energy increase on to the transverse phase space area are considered by putting in accelerating matrices of each resonators. The second program is used to simulate particle longitudinal motions. Beam longitudinal motions are calculated with program ENTIME also, with which visual pictures in the Energy-Time phase space can be displayed on the terminal screen. Besides, the stability of the particle periodic motions in the radial directions are considered and calculated

  5. A one-dimensional transport code for the simulation of D-T burning tokamak plasma

    International Nuclear Information System (INIS)

    Tone, Tatsuzo; Maki, Koichi; Kasai, Masao; Nishida, Hidetsugu

    1980-11-01

    A one-dimensional transport code for D-T burning tokamak plasma has been developed, which simulates the spatial behavior of fuel ions(D, T), alpha particles, impurities, temperatures of ions and electrons, plasma current, neutrals, heating of alpha and injected beam particles. The basic transport equations are represented by one generalized equation so that the improvement of models and the addition of new equations may be easily made. A model of burn control using a variable toroidal field ripple is employed. This report describes in detail the simulation model, numerical method and the usage of the code. Some typical examples to which the code has been applied are presented. (author)

  6. The effects of magnetic fringe fields on beam dynamics in a beam transport line of a terahertz FEL source

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Han [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074, Hubei (China); Xiong, Yongqian, E-mail: yqxiong@mail.hust.edu.cn [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074, Hubei (China); Pei, Yuanji [National Synchrotron Radiation laboratory, University of Science and Technology of China, Hefei 230029, Anhui (China)

    2014-11-11

    The transport line used in a terahertz FEL device has to transport electron beam through the entire system efficiently and meet the requirements of the beam parameters at the undulator entrance. Due to space limitations, the size of the magnets (five quadrupoles and two bending magnets) employed in the transport line was limited, and some devices were densely packed. In this paper, analyses of the effect of fringe fields and magnetic interference of magnets are presented. 3D models of these magnets are built and their linear optical properties are compared with those obtained by hard edge models. The results indicated that the effects of these factors are significant and they would cause a mismatch of the beam at the exit of the transport line under the preliminary lattice design. To solve this problem, the beam was re-matched using the particle swarm optimization algorithm.

  7. Object-Oriented Parallel Particle-in-Cell Code for Beam Dynamics Simulation in Linear Accelerators

    International Nuclear Information System (INIS)

    Qiang, J.; Ryne, R.D.; Habib, S.; Decky, V.

    1999-01-01

    In this paper, we present an object-oriented three-dimensional parallel particle-in-cell code for beam dynamics simulation in linear accelerators. A two-dimensional parallel domain decomposition approach is employed within a message passing programming paradigm along with a dynamic load balancing. Implementing object-oriented software design provides the code with better maintainability, reusability, and extensibility compared with conventional structure based code. This also helps to encapsulate the details of communications syntax. Performance tests on SGI/Cray T3E-900 and SGI Origin 2000 machines show good scalability of the object-oriented code. Some important features of this code also include employing symplectic integration with linear maps of external focusing elements and using z as the independent variable, typical in accelerators. A successful application was done to simulate beam transport through three superconducting sections in the APT linac design

  8. Bending magnets for the CBA beam-transport line

    International Nuclear Information System (INIS)

    Thern, R.E.

    1983-01-01

    The beam-transport line from the AGS to CBA requires 68 large bending magnets, consisting of pure dipoles and two types of combined function gradient magnets. All three types were designed with magnetic-field calculation program POISSON, using the same exterior dimensions and coil package. The design goal of +-1% momentum acceptance for the transport line required a wide horizontal aperture, with a much-smaller vertical aperture for economy. Two prototypes of one gradient magnet were built, and a facility constructed to measure them and the later production magnets. Measurements were done using both a long coil and a point coil (Rawson-Lush gaussmeter). Preliminary results show δB/B - 3 , δG/G - 2 , and δB 2 /B - 4 cm - 2 over the beam aperture. Due to end effects, the actual gradient differs from the design gradient by 1%, which has been compensated for in the beam-line design

  9. Experimental study of the transport limits of intense heavy ion beams in the HCX

    International Nuclear Information System (INIS)

    Prost, L.R.; Bieniosek, F.M.; Celata, C.M.; Dugan, C.C.; Faltens, A.; Seidl, P.A.; Waldron, W.L.; Cohen, R.; Friedman, A.; Kireeff Covo, M.; Lund, S.M.; Molvik, A.W.; Haber, I.

    2004-01-01

    The High Current Experiment (HCX) at Lawrence Berkeley National Laboratory is part of the US program to explore heavy-ion beam transport at a scale representative of the low-energy end of an induction linac driver for fusion energy production. The primary mission of this experiment is to investigate aperture fill factors acceptable for the transport of space-charge-dominated heavy-ion beams at high space-charge intensity (line charge density up to ∼ 0.2 (micro)C/m) over long pulse durations (4 (micro)s) in alternating gradient focusing lattices of electrostatic or magnetic quadrupoles. The experiment also contributes to the practical baseline knowledge of intense beam manipulations necessary for the design, construction and operation of a heavy ion driver for inertial fusion. This experiment is testing transport issues resulting from nonlinear space-charge effects and collective modes, beam centroid alignment and beam steering, matching, image charges, halo, electron cloud effects, and longitudinal bunch control. We first present the results for a coasting 1 MeV K + ion beam transported through the first ten electrostatic transport quadrupoles, measured with optical beam-imaging and double-slit phase-space diagnostics. This includes studies at two different radial fill factors (60% and 80%), for which the beam transverse distribution was characterized in detail. Additionally, beam energy measurements will be shown. We then discuss the first results of beam transport through four pulsed room-temperature magnetic quadrupoles (located downstream of the electrostatic quadrupoles), where the beam dynamics become more sensitive to the presence of secondary electrons

  10. Beam-dynamics codes used at DARHT

    Energy Technology Data Exchange (ETDEWEB)

    Ekdahl, Jr., Carl August [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-01

    Several beam simulation codes are used to help gain a better understanding of beam dynamics in the DARHT LIAs. The most notable of these fall into the following categories: for beam production – Tricomp Trak orbit tracking code, LSP Particle in cell (PIC) code, for beam transport and acceleration – XTR static envelope and centroid code, LAMDA time-resolved envelope and centroid code, LSP-Slice PIC code, for coasting-beam transport to target – LAMDA time-resolved envelope code, LSP-Slice PIC code. These codes are also being used to inform the design of Scorpius.

  11. Preliminary design of the beam transport system for the Milan biomedical cyclotron

    International Nuclear Information System (INIS)

    Silari, M.

    1988-01-01

    This report illustrates the preliminary design of the beam transport system for the Scanditronix MC40 cyclotron to be installed in Milan. The Cyclotron will be dedicated to biomedical research and the different experimental conditions that could occur will require a beam transport system flexible enough so as to deliver beams with the specified characteristics. The report describes the computer codes used, the calculations performed and the results obtained. The complete configuration of the beam lines serving the first two target rooms is given, together with typical beam profiles and the emittance ellipse variation along the transfer channels

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

    Science.gov (United States)

    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.

  13. Numerical simulation of electron beam welding with beam oscillations

    Science.gov (United States)

    Trushnikov, D. N.; Permyakov, G. L.

    2017-02-01

    This research examines the process of electron-beam welding in a keyhole mode with the use of beam oscillations. We study the impact of various beam oscillations and their parameters on the shape of the keyhole, the flow of heat and mass transfer processes and weld parameters to develop methodological recommendations. A numerical three-dimensional mathematical model of electron beam welding is presented. The model was developed on the basis of a heat conduction equation and a Navier-Stokes equation taking into account phase transitions at the interface of a solid and liquid phase and thermocapillary convection (Marangoni effect). The shape of the keyhole is determined based on experimental data on the parameters of the secondary signal by using the method of a synchronous accumulation. Calculations of thermal and hydrodynamic processes were carried out based on a computer cluster, using a simulation package COMSOL Multiphysics.

  14. The beam transport system

    International Nuclear Information System (INIS)

    1986-01-01

    The first proton beams have been transported along the transfer beamline and the diagnostic components have thus been used and tested under real operating conditions. The various electronic systems have been linked to the control system and the equipment can now be operated from the control console. The performance of the diagnostic system for the transfer beamline is satisfactory. The beam diagnostic components for the high-energy beamlines up to the isotope production and neutron therapy vaults and the first experimental target rooms have been installed. The high-energy slits have been delivered. The scanner and harp electronics have been installed and linked to their respective components in the beamlines. The pneumatic acuator control electronics has been manufactured, installed and is operational; provision has been made for special control features of the equipment in the therapy beamline. The high-voltage bias supply for the Faraday cups has been implemented. The installation of the beam current measurement system is nearing completion although part of it is already operational. A coaxial relay multiplexer for the capacitive phase probe signals has been manufactured and installed. The diagnostic equipment for the beamlines to isotope production and neutron therapy is thus ready for operation. 4 figs

  15. Ultrasonic Beam Propagation in Highly Anisotropic Materials Simulated by Multi-Gaussian Beams

    International Nuclear Information System (INIS)

    Jeong, Hyun Jo; Schmerr, Lester W.

    2007-01-01

    The necessity of nondestructively inspecting fiber-reinforced composites, austenitic steels, and other inherently anisotropic materials has stimulated considerable interest in developing beam models for anisotropic media. The properties of slowness surface play key role in the beam models based on the paraxial approximation. In this paper, we apply a modular multi-Gaussian beam (MMGB) model to study the effects of material anisotropy on ultrasonic beam profile. It is shown that the anisotropic effects of beam skew and excess beam divergence enter into the MMGB model through parameters defining the slope and curvature of the slowness surface. The overall beam profile is found when the quasi longitudinal (qL) beam propagates in the symmetry plane of a transversely isotropic gr/ep composite. Simulation results are presented to illustrate the effects of these parameters on ultrasonic beam diffraction and beam skew. The MMGB calculations are also checked by comparing the anisotropy factor and beam skew angle with other analytical solutions

  16. Achromatic and isochronous electron beam transport for tunable free electron lasers

    International Nuclear Information System (INIS)

    Bengtsson, J.; Kim, K.J.

    1991-09-01

    We have continued the study of a suitable electron beam transport line, which is both isochronous and achromatic, for the free electron laser being designed at Lawrence Berkeley Laboratory. A refined version of the beam transport optics is discussed that accommodates two different modes of FEL wavelength tuning. For the fine tuning involving a small change of the electron beam energy, sextupoles are added to cancel the leading nonlinear dispersion. For the main tuning involving the change of the undulator gap, a practical solution of maintaining the beam matching condition is presented. Calculation of the higher order aberrations is facilitated by a newly developed code. 11 refs., 4 figs., 3 tabs

  17. The separated-sector cyclotron: beam transport

    International Nuclear Information System (INIS)

    1989-01-01

    The diagnostic components that were ordered for the rest of the proposed beamlines at the NAC have been delivered. Design and manufacture of a special harp for the beam swinger has commenced. The Faraday cups and slits in the transfer beamline were replaced by water-cooled versions, owing to the decision to transport beams of higher intensity than initially specified. A prototype water-cooled slit for use in the low-energy beamline emittance measurement system has been installed, replacing the previous uncooled slit, to meet the requirement to measure the emittance of high-intensity beams. Software to automate the emittance measurement procedure is being developed. The method of calibration and alignment of the beamline scanners has been improved resulting in a more accurate measurement of the beam position. Software is being developed to regulate the beam current on the neutron therapy target. Current measurement from the target is used as feedback to regulate the aperture of a slit-system in the low-energy transfer beamline. This procedure will be implemented as soon as final tests have been carried out during the next scheduled shutdown. 3 figs

  18. Third-Order Transport with MAD Input: A Computer Program for Designing Charged Particle Beam Transport Systems

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Karl

    1998-10-28

    TRANSPORT has been in existence in various evolutionary versions since 1963. The present version of TRANSPORT is a first-, second-, and third-order matrix multiplication computer program intended for the design of static-magnetic beam transport systems.

  19. Optimization of GATE and PHITS Monte Carlo code parameters for uniform scanning proton beam based on simulation with FLUKA general-purpose code

    Energy Technology Data Exchange (ETDEWEB)

    Kurosu, Keita [Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Suita, Osaka 565-0871 (Japan); Department of Radiation Oncology, Osaka University Graduate School of Medicine, Suita, Osaka 565-0871 (Japan); Takashina, Masaaki; Koizumi, Masahiko [Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Suita, Osaka 565-0871 (Japan); Das, Indra J. [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN 46202 (United States); Moskvin, Vadim P., E-mail: vadim.p.moskvin@gmail.com [Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN 46202 (United States)

    2014-10-01

    Although three general-purpose Monte Carlo (MC) simulation tools: Geant4, FLUKA and PHITS have been used extensively, differences in calculation results have been reported. The major causes are the implementation of the physical model, preset value of the ionization potential or definition of the maximum step size. In order to achieve artifact free MC simulation, an optimized parameters list for each simulation system is required. Several authors have already proposed the optimized lists, but those studies were performed with a simple system such as only a water phantom. Since particle beams have a transport, interaction and electromagnetic processes during beam delivery, establishment of an optimized parameters-list for whole beam delivery system is therefore of major importance. The purpose of this study was to determine the optimized parameters list for GATE and PHITS using proton treatment nozzle computational model. The simulation was performed with the broad scanning proton beam. The influences of the customizing parameters on the percentage depth dose (PDD) profile and the proton range were investigated by comparison with the result of FLUKA, and then the optimal parameters were determined. The PDD profile and the proton range obtained from our optimized parameters list showed different characteristics from the results obtained with simple system. This led to the conclusion that the physical model, particle transport mechanics and different geometry-based descriptions need accurate customization in planning computational experiments for artifact-free MC simulation.

  20. Optimization of GATE and PHITS Monte Carlo code parameters for uniform scanning proton beam based on simulation with FLUKA general-purpose code

    International Nuclear Information System (INIS)

    Kurosu, Keita; Takashina, Masaaki; Koizumi, Masahiko; Das, Indra J.; Moskvin, Vadim P.

    2014-01-01

    Although three general-purpose Monte Carlo (MC) simulation tools: Geant4, FLUKA and PHITS have been used extensively, differences in calculation results have been reported. The major causes are the implementation of the physical model, preset value of the ionization potential or definition of the maximum step size. In order to achieve artifact free MC simulation, an optimized parameters list for each simulation system is required. Several authors have already proposed the optimized lists, but those studies were performed with a simple system such as only a water phantom. Since particle beams have a transport, interaction and electromagnetic processes during beam delivery, establishment of an optimized parameters-list for whole beam delivery system is therefore of major importance. The purpose of this study was to determine the optimized parameters list for GATE and PHITS using proton treatment nozzle computational model. The simulation was performed with the broad scanning proton beam. The influences of the customizing parameters on the percentage depth dose (PDD) profile and the proton range were investigated by comparison with the result of FLUKA, and then the optimal parameters were determined. The PDD profile and the proton range obtained from our optimized parameters list showed different characteristics from the results obtained with simple system. This led to the conclusion that the physical model, particle transport mechanics and different geometry-based descriptions need accurate customization in planning computational experiments for artifact-free MC simulation

  1. Fluid simulation for two laser beams co-propagating in underdense plasma

    International Nuclear Information System (INIS)

    Mahdy, A.I.

    2004-09-01

    2D simulations code was constructed in order simulate the interactions of two co-propagating laser beams with underdense plasma. Simulations results at different laser intensities and separation-distances between the beams centroids were presented. In the results the effects of the laser intensities on the self-focusing and merging of the propagating beams were shown. In addition, the influence of increasing the separation-distance on the beams stability and trajectories were studied. A comparison with previous simulations at similar conditions was carried out in order to evaluate the numerical technique used to solve the basic equations. (author)

  2. Monte Carlo simulation of beam characteristics from small fields based on TrueBeam flattening-filter-free mode

    International Nuclear Information System (INIS)

    Feng, Zhongsu; Yue, Haizhen; Zhang, Yibao; Wu, Hao; Cheng, Jinsheng; Su, Xu

    2016-01-01

    Through the Monte Carlo (MC) simulation of 6 and 10 MV flattening-filter-free (FFF) beams from Varian TrueBeam accelerator, this study aims to find the best incident electron distribution for further studying the small field characteristics of these beams. By incorporating the training materials of Varian on the geometry and material parameters of TrueBeam Linac head, the 6 and 10 MV FFF beams were modelled using the BEAMnrc and DOSXYZnrc codes, where the percentage depth doses (PDDs) and the off-axis ratios (OARs) curves of fields ranging from 4 × 4 to 40 × 40 cm 2 were simulated for both energies by adjusting the incident beam energy, radial intensity distribution and angular spread, respectively. The beam quality and relative output factor (ROF) were calculated. The simulations and measurements were compared using Gamma analysis method provided by Verisoft program (PTW, Freiburg, Germany), based on which the optimal MC model input parameters were selected and were further used to investigate the beam characteristics of small fields. The Full Width Half Maximum (FWHM), mono-energetic energy and angular spread of the resultant incident Gaussian radial intensity electron distribution were 0.75 mm, 6.1 MeV and 0.9° for the nominal 6 MV FFF beam, and 0.7 mm, 10.8 MeV and 0.3° for the nominal 10 MV FFF beam respectively. The simulation was mostly comparable to the measurement. Gamma criteria of 1 mm/1 % (local dose) can be met by all PDDs of fields larger than 1 × 1 cm 2 , and by all OARs of no larger than 20 × 20 cm 2 , otherwise criteria of 1 mm/2 % can be fulfilled. Our MC simulated ROFs agreed well with the measured ROFs of various field sizes (the discrepancies were less than 1 %), except for the 1 × 1 cm 2 field. The MC simulation agrees well with the measurement and the proposed model parameters can be clinically used for further dosimetric studies of 6 and 10 MV FFF beams

  3. Simulating the Beam-line at CERN's ISOLDE Experiment

    CERN Document Server

    McGrath, Casey

    2013-01-01

    Maximizing the optical matching along portions of the ISOLDE beam-line and automating this procedure will make it easier for scientists to determine what the strengths of the electrical elds of each beam-line element should be in order to reduce particle loss. Simulations are run using a program called MAD-X, however, certain issues were discovered that hindered an immediate success of the simulations. Specifically, the transfer matrices for electrostatic components like the switchyards, kickers, and electric quadrupoles were missing from the original coding. The primary aim of this project was to design these components using AutoCAD and then extract the transfer matrices using SIMION. Future work will then implement these transfer matrices into the MAD-X code to make the simulations of the beam-line more accurate.

  4. Simulation and track reconstruction for beam telescopes

    CERN Document Server

    Maqbool, Salman

    2017-01-01

    Beam telescopes are used for testing new detectors under development. Sensors are placed and a particle beam is passed through them. To test these novel detectors and determine their properties, the particle tracks need to be reconstructed from the known detectors in the telescope. Based on the reconstructed track, it’s predicted hits on the Device under Test (DUT) are compared with the actual hits on the DUT. Several methods exist for track reconstruction, but most of them don’t account for the effects of multiple scattering. General Broken Lines is one such algorithm which incorporates these effects during reconstruction. The aim of this project was to simulate the beam telescope and extend the track reconstruction framework for the FE-I4 telescope, which takes these effects into account. Section 1 introduces the problem, while section 2 focuses on beam telescopes. This is followed by the Allpix2 simulation framework in Section 3. And finally, Section 4 introduces the Proteus track reconstruction framew...

  5. Simulation and Track Reconstruction for Beam Telescopes

    CERN Document Server

    Maqbool, Salman

    2017-01-01

    Beam telescopes are an important tool to test new detectors under development in a particle beam. To test these novel detectors and determine their properties, the particle tracks need to be reconstructed from the known detectors in the telescope. Based on the reconstructed track, its predicted position on the Device under Test (DUT) are compared with the actual hits on the DUT. Several methods exist for track reconstruction, but most of them do not account for the effects of multiple scattering. General Broken Lines is one such algorithm which incorporates these effects during reconstruction. The aim of this project was to simulate the beam telescope and extend the track reconstruction framework for the FE-I4 telescope, which takes these effects into account. Section 1 introduces the problem, while section 2 focuses on beam telescopes. This is followed by the Allpix2 simulation framework in Section 3. And finally, Section 4 introduces the Proteus track reconstruction framework along with the General Broken ...

  6. Two Methods For Simulating the Strong-Strong Beam-Beam Interaction in Hadron Colliders

    International Nuclear Information System (INIS)

    Warnock, Robert L.

    2002-01-01

    We present and compare the method of weighted macro particle tracking and the Perron-Frobenius operator technique for simulating the time evolution of two beams coupled via the collective beam-beam interaction in 2-D and 4-D (transverse) phase space. The coherent dipole modes, with and without lattice nonlinearities and external excitation, are studied by means of the Vlasov-Poisson system

  7. Integration and evaluation of automated Monte Carlo simulations in the clinical practice of scanned proton and carbon ion beam therapy.

    Science.gov (United States)

    Bauer, J; Sommerer, F; Mairani, A; Unholtz, D; Farook, R; Handrack, J; Frey, K; Marcelos, T; Tessonnier, T; Ecker, S; Ackermann, B; Ellerbrock, M; Debus, J; Parodi, K

    2014-08-21

    Monte Carlo (MC) simulations of beam interaction and transport in matter are increasingly considered as essential tools to support several aspects of radiation therapy. Despite the vast application of MC to photon therapy and scattered proton therapy, clinical experience in scanned ion beam therapy is still scarce. This is especially the case for ions heavier than protons, which pose additional issues like nuclear fragmentation and varying biological effectiveness. In this work, we present the evaluation of a dedicated framework which has been developed at the Heidelberg Ion Beam Therapy Center to provide automated FLUKA MC simulations of clinical patient treatments with scanned proton and carbon ion beams. Investigations on the number of transported primaries and the dimension of the geometry and scoring grids have been performed for a representative class of patient cases in order to provide recommendations on the simulation settings, showing that recommendations derived from the experience in proton therapy cannot be directly translated to the case of carbon ion beams. The MC results with the optimized settings have been compared to the calculations of the analytical treatment planning system (TPS), showing that regardless of the consistency of the two systems (in terms of beam model in water and range calculation in different materials) relevant differences can be found in dosimetric quantities and range, especially in the case of heterogeneous and deep seated treatment sites depending on the ion beam species and energies, homogeneity of the traversed tissue and size of the treated volume. The analysis of typical TPS speed-up approximations highlighted effects which deserve accurate treatment, in contrast to adequate beam model simplifications for scanned ion beam therapy. In terms of biological dose calculations, the investigation of the mixed field components in realistic anatomical situations confirmed the findings of previous groups so far reported only in

  8. Electron density measurements during ion beam transport on Gamble II

    International Nuclear Information System (INIS)

    Weber, B.V.; Hinshelwood, D.D.; Neri, J.M.; Ottinger, P.F.; Rose, D.V.; Stephanakis, S.J.; Young, F.C.

    1999-01-01

    High-sensitivity laser interferometry was used to measure the electron density created when an intense proton beam (100 kA, 1 MeV, 50 ns) from the Gamble II generator was transported through low-pressure gas as part of a project investigating Self-Pinched Transport (SPT) of intense ion beams. This measurement is non-perturbing and sufficiently quantitative to allow benchmarking of codes (particularly IPROP) used to model beam-gas interaction and ion-beam transport. Very high phase sensitivity is required for this measurement. For example, a 100-kA, 1-MeV, 10-cm-radius proton beam with uniform current density has a line-integrated proton density equal to n b L = 3 x 10 13 cm -2 . An equal electron line-density, n e L = n b L, (expected for transport in vacuum) will be detected as a phase shift of the 1.064 microm laser beam of only 0.05degree, or an optical path change of 1.4 x 10 -4 waves (about the size of a hydrogen atom). The time-history of the line-integrated electron density, measured across a diameter of the transport chamber at 43 cm from the input aperture, starts with the proton arrival time and decays differently depending on the gas pressure. The gas conditions included vacuum (10 -4 Torr air), 30 to 220 mTorr He, and 1 Torr air. The measured densities vary by three orders of magnitude, from 10 13 to 10 16 cm -2 for the range of gas pressures investigated. In vacuum, the measured electron densities indicate only co-moving electrons (n e L approximately n b L). In He, when the gas pressure is sufficient for ionization by beam particles and SPT is observed, n e L increases to about 10 n b L. At even higher pressures where electrons contribute to ionization, even higher electron densities are observed with an ionization fraction of about 2%. The diagnostic technique as used on the SPT experiment will be described and a summary of the results will be given. The measurements are in reasonable agreement with theoretical predictions from the IPROP code

  9. Design and initial tests of beam current monitoring systems for the APS transport lines

    International Nuclear Information System (INIS)

    Wang, Xucheng.

    1992-01-01

    The non-intercepting beam current monitoring systems suitable for a wide, range of beam parameters have been developed for the Advanced Photon Source (APS) low energy transport lines and high energy transport line. The positron or electron beam pulse in the transport lines wig have peak beam currents ranging from 8 mA to 29 A with pulse widths varying from 120 ps to 30 ns and pulse repetition rates from 2 Hz to 60 Hz. The peak beam current or total beam charge is measured with the fast or integrating current transformer, respectively, manufactured by Bergoz. In-house high speed beam signal processing electronics provide a DC level output proportional to the peak current or total charge for the digitizer input. The prototype systems were tested on the linacs which have beam pulse structures similar to that of the APS transport lines. This paper describes the design of beam signal processing electronics and grounding and shielding methods for current transformers. The results of the initial operations are presented. A short introduction on the preliminary design of current monitoring systems for the APS rings is also included

  10. High intensity proton beam transportation through fringe field of 70 MeV compact cyclotron to beam line targets

    Science.gov (United States)

    Zhang, Xu; Li, Ming; Wei, Sumin; Xing, Jiansheng; Hu, Yueming; Johnson, Richard R.; Piazza, Leandro; Ryjkov, Vladimir

    2016-06-01

    From the stripping points, the high intensity proton beam of a compact cyclotron travels through the fringe field area of the machine to the combination magnet. Starting from there the beams with various energy is transferred to the switching magnet for distribution to the beam line targets. In the design of the extraction and transport system for the compact proton cyclotron facilities, such as the 70 MeV in France and the 100 MeV in China, the space charge effect as the beam crosses the fringe field has not been previously considered; neither has the impact on transverse beam envelope coupled from the longitudinal direction. Those have been concerned much more with the higher beam-power because of the beam loss problem. In this paper, based on the mapping data of 70 MeV cyclotron including the fringe field by BEST Cyclotron Inc (BEST) and combination magnet field by China Institute of Atomic Energy (CIAE), the beam extraction and transport are investigated for the 70 MeV cyclotron used on the SPES project at Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro (INFN-LNL). The study includes the space charge effect and longitudinal and transverse coupling mentioned above, as well as the matching of beam optics using the beam line for medical isotope production as an example. In addition, the designs of the ±45° switching magnets and the 60° bending magnet for the extracted beam with the energy from 35 MeV to 70 MeV have been made. Parts of the construction and field measurements of those magnets have been done as well. The current result shows that, the design considers the complexity of the compact cyclotron extraction area and fits the requirements of the extraction and transport for high intensity proton beam, especially at mA intensity levels.

  11. High intensity proton beam transportation through fringe field of 70 MeV compact cyclotron to beam line targets

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xu, E-mail: emmazhang103@gmail.com [China Institute of Atomic Energy (China); Li, Ming; Wei, Sumin; Xing, Jiansheng; Hu, Yueming [China Institute of Atomic Energy (China); Johnson, Richard R.; Piazza, Leandro; Ryjkov, Vladimir [BEST Cyclotron Inc (Canada)

    2016-06-01

    From the stripping points, the high intensity proton beam of a compact cyclotron travels through the fringe field area of the machine to the combination magnet. Starting from there the beams with various energy is transferred to the switching magnet for distribution to the beam line targets. In the design of the extraction and transport system for the compact proton cyclotron facilities, such as the 70 MeV in France and the 100 MeV in China, the space charge effect as the beam crosses the fringe field has not been previously considered; neither has the impact on transverse beam envelope coupled from the longitudinal direction. Those have been concerned much more with the higher beam-power because of the beam loss problem. In this paper, based on the mapping data of 70 MeV cyclotron including the fringe field by BEST Cyclotron Inc (BEST) and combination magnet field by China Institute of Atomic Energy (CIAE), the beam extraction and transport are investigated for the 70 MeV cyclotron used on the SPES project at Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro (INFN–LNL). The study includes the space charge effect and longitudinal and transverse coupling mentioned above, as well as the matching of beam optics using the beam line for medical isotope production as an example. In addition, the designs of the ±45° switching magnets and the 60° bending magnet for the extracted beam with the energy from 35 MeV to 70 MeV have been made. Parts of the construction and field measurements of those magnets have been done as well. The current result shows that, the design considers the complexity of the compact cyclotron extraction area and fits the requirements of the extraction and transport for high intensity proton beam, especially at mA intensity levels.

  12. Simulations of longitudinal beam dynamics of space-charge dominated beams for heavy ion fusion

    International Nuclear Information System (INIS)

    Miller, D.A.C.

    1994-12-01

    The longitudinal instability has potentially disastrous effects on the ion beams used for heavy ion driven inertial confinement fusion. This instability is a open-quotes resistive wallclose quotes instability with the impedance coining from the induction modules in the accelerator used as a driver. This instability can greatly amplify perturbations launched from the beam head and can prevent focusing of the beam onto the small spot necessary for fusion. This instability has been studied using the WARPrz particle-in-cell code. WARPrz is a 2 1/2 dimensional electrostatic axisymmetric code. This code includes a model for the impedance of the induction modules. Simulations with resistances similar to that expected in a driver show moderate amounts of growth from the instability as a perturbation travels from beam head to tail as predicted by cold beam fluid theory. The perturbation reflects off the beam tail and decays as it travels toward the beam head. Nonlinear effects cause the perturbation to steepen during reflection. Including the capacitive component of the, module impedance. has a partially stabilizing effect on the longitudinal instability. This reduction in the growth rate is seen in both cold beam fluid theory and in simulations with WARPrz. Instability growth rates for warm beams measured from WARPrz are lower than cold beam fluid theory predicts. Longitudinal thermal spread cannot account for this decrease in the growth rate. A mechanism for coupling the transverse thermal spread to decay of the longitudinal waves is presented. The longitudinal instability is no longer a threat to the heavy ion fusion program. The simulations in this thesis have shown that the growth rate for this instability will not be as large as earlier calculations predicted

  13. Transport and acceleration of the high-current ion beam in magneto-isolated gap

    International Nuclear Information System (INIS)

    Karas', V.I.; Kornilov, E.A.; Manuilenko, O.V.; Fedorovskaya, O.V.; Tarakanov, V.P.

    2015-01-01

    The possibility of transportation and acceleration of the high-current ion beam in the magneto-isolated gap has been demonstrated. Found the parameters of the system and beams (the magnetic field produced by the coils with opposing currents, the size of the system, and the parameters of the beams), under which the uniform acceleration of the high-current ion beam all along the gap length is realized. It is shown that the quality of the ion beam, during transport and acceleration, at the exit of the gap is acceptable for many technological applications.

  14. Chamber transport

    International Nuclear Information System (INIS)

    Olson, Craig L.

    2001-01-01

    Heavy ion beam transport through the containment chamber plays a crucial role in all heavy ion fusion (HIF) scenarios. Here, several parameters are used to characterize the operating space for HIF beams; transport modes are assessed in relation to evolving target/accelerator requirements; results of recent relevant experiments and simulations of HIF transport are summarized; and relevant instabilities are reviewed. All transport options still exist, including (1) vacuum ballistic transport, (2) neutralized ballistic transport, and (3) channel-like transport. Presently, the European HIF program favors vacuum ballistic transport, while the US HIF program favors neutralized ballistic transport with channel-like transport as an alternate approach. Further transport research is needed to clearly guide selection of the most attractive, integrated HIF system

  15. LINAC4 low energy beam measurements

    CERN Document Server

    Hein, L M; Lallement, J B; Lombardi, A M; Midttun, O; Posocco, P; Scrivens, R

    2012-01-01

    Linac4 is a 160 MeV normal-conducting linear accelerator for negative Hydrogen ions (H−), which will replace the 50 MeV proton Linac (Linac2) as linear injector for the CERN accelerators. The low energy part, comprising a 45 keV Low Energy Beam Transport system (LEBT), a 3 MeV Radiofrequency Quadrupole (RFQ) and a Medium Energy Beam Transport (MEBT) is being assembled in a dedicated test stand for pre-commissioning with a proton beam. During 2011 extensive measurements were done after the source and after the LEBT with the aim of preparing the RFQ commissioning and validating the simulation tools, indispensable for future source upgrades. The measurements have been thoroughly simulated with a multi-particle code, including 2D magnetic field maps, error studies, steering studies and the generation of beam distribution from measurements. Emittance, acceptance and transmission measurements will be presented and compared to the results of the simulations.

  16. Numerical Simulation of Beam-Beam Effects in the Proposed Electron-Ion Colider at Jefferson Lab

    International Nuclear Information System (INIS)

    Terzic, Balsa; Zhang, Yuhong

    2010-01-01

    One key limiting factor to a collider luminosity is beam-beam interactions which usually can cause serious emittance growth of colliding beams and fast reduction of luminosity. Such nonlinear collective beam effect can be a very serious design challenge when the machine parameters are pushed into a new regime. In this paper, we present simulation studies of the beam-beam effect for a medium energy ring-ring electron-ion collider based on CEBAF.

  17. Perturbative studies of toroidal momentum transport using neutral beam injection modulation in the Joint European Torus: Experimental results, analysis methodology, and first principles modeling

    DEFF Research Database (Denmark)

    Mantica, P.; Tala, T.; Ferreira, J.S.

    2010-01-01

    Perturbative experiments have been carried out in the Joint European Torus [Fusion Sci. Technol. 53(4) (2008)] in order to identify the diffusive and convective components of toroidal momentum transport. The torque source was modulated either by modulating tangential neutral beam power...... or by modulating in antiphase tangential and normal beams to produce a torque perturbation in the absence of a power perturbation. The resulting periodic perturbation in the toroidal rotation velocity was modeled using time-dependent transport simulations in order to extract empirical profiles of momentum...

  18. Heavy ion beam transport through liquid lithium first wall ICF reactor cavities

    International Nuclear Information System (INIS)

    Stroud, P.D.

    1985-01-01

    This analysis addresses the critical issue of the final transport of a heavy ion beam in an inertial confinement fusion reactor. The beam must traverse the reaction chamber from the final focusing lens to the target without being disrupted. This requirement has a strong impact on the reactor design. It is essential to the development of ICF fusion reactor technology, that the restrictions placed on the reactor engineering parameters by final beam transport consideration be understood early on

  19. Experimental study of the longitudinal instability for beam transport

    International Nuclear Information System (INIS)

    Reiser, M.; Wang, J.G.; Guo, W.M.; Wang, D.X.

    1990-01-01

    Theoretical model for beam longitudinal instability in a transport pipe with general wall impedance is considered. The result shows that a capacitive wall tends to stabilize the beam. The experimental study of the instability for a pure resistive-wall is presented, including the design parameters, setup and components for the experiment. 6 refs., 3 figs

  20. Conditioner for a helically transported electron beam

    International Nuclear Information System (INIS)

    Wang, C.

    1992-05-01

    The kinetic theory is developed to investigate a conditioner for a helically imported electron beam. Linear expressions for axial velocity spread are derived. Numerical simulation is used to check the theoretical results and examine nonlinear aspects of the conditioning process. The results show that in the linear regime the action of the beam conditioner on a pulsed beam mainly depends on the phase at which the beam enters the conditioner and depends only slightly on the operating wavelength. In the nonlinear regime, however, the action of the conditioner strongly depends on the operating wavelength and only slightly upon the entrance phase. For a properly chosen operating wavelength, a little less than the electron's relativistic cyclotron wavelength, the conditioner can decrease the axial velocity spread of a pulsed beam down to less than one-third of its initial value

  1. Bench-marking beam-beam simulations using coherent quadrupole effects

    International Nuclear Information System (INIS)

    Krishnagopal, S.; Chin, Y.H.

    1992-06-01

    Computer simulations are used extensively in the study of the beam-beam interaction. The proliferation of such codes raises the important question of their reliability, and motivates the development of a dependable set of bench-marks. We argue that rather than detailed quantitative comparisons, the ability of different codes to predict the same qualitative physics should be used as a criterion for such bench-marks. We use the striking phenomenon of coherent quadrupole oscillations as one such bench-mark, and demonstrate that our codes do indeed observe this behaviour. We also suggest some other tests that could be used as bench-marks

  2. Bench-marking beam-beam simulations using coherent quadrupole effects

    International Nuclear Information System (INIS)

    Krishnagopal, S.; Chin, Y.H.

    1992-01-01

    Computer simulations are used extensively in the study of the beam-beam interaction. The proliferation of such codes raises the important question of their reliability, and motivates the development of a dependable set of bench-marks. We argue that rather than detailed quantitative comparisons, the ability of different codes to predict the same qualitative physics should be used as a criterion for such bench-marks. We use the striking phenomenon of coherent quadrupole oscillations as one such bench-mark, and demonstrate that our codes do indeed observe this behavior. We also suggest some other tests that could be used as bench-marks

  3. Transport Simulations for Fast Ignition on NIF

    Energy Technology Data Exchange (ETDEWEB)

    Strozzi, D J; Tabak, M; Grote, D P; Cohen, B I; Shay, H D; Town, R J; Kemp, A J; Key, M

    2009-10-26

    We are designing a full hydro-scale cone-guided, indirect-drive FI coupling experiment, for NIF, with the ARC-FIDO short-pulse laser. Current rad-hydro designs with limited fuel jetting into cone tip are not yet adequate for ignition. Designs are improving. Electron beam transport simulations (implicit-PIC LSP) show: (1) Magnetic fields and smaller angular spreads increase coupling to ignition-relevant 'hot spot' (20 um radius); (2) Plastic CD (for a warm target) produces somewhat better coupling than pure D (cryogenic target) due to enhanced resistive B fields; and (3) The optimal T{sub hot} for this target is {approx} 1 MeV; coupling falls by 3x as T{sub hot} rises to 4 MeV.

  4. Beam dynamics simulation in the X-ray Compton source

    International Nuclear Information System (INIS)

    Gladkikh, P.; Karnaukhov, I.; Telegin, Yu.; Shcherbakov, A.; Zelinsky, A.

    2002-01-01

    At the National Science Center 'Kharkov Institute of Physics and Technology' the X-ray source based on Compton scattering has been developed. The computer code for simulation of electron beam dynamics with taking into account the Compton scattering effect based on Monte Carlo method is described in this report. The first results of computer simulation of beam dynamics with electron-photon interaction, parameters of electron and photon beams are presented. Calculations were carried out with the lattice of synchrotron light source SRS-800 Ukrainian Synchrotron Center

  5. Beam dynamics simulation in the X-ray Compton source

    CERN Document Server

    Gladkikh, P; Telegin, Yu P; Shcherbakov, A; Zelinsky, A

    2002-01-01

    At the National Science Center 'Kharkov Institute of Physics and Technology' the X-ray source based on Compton scattering has been developed. The computer code for simulation of electron beam dynamics with taking into account the Compton scattering effect based on Monte Carlo method is described in this report. The first results of computer simulation of beam dynamics with electron-photon interaction, parameters of electron and photon beams are presented. Calculations were carried out with the lattice of synchrotron light source SRS-800 Ukrainian Synchrotron Center.

  6. Neutron transportation simulator

    International Nuclear Information System (INIS)

    Uenohara, Yuzo.

    1995-01-01

    In the present invention, problems in an existent parallelized monte carlo method is solved, and behaviors of neutrons in a large scaled system are accurately simulated at a high speed. Namely, a neutron transportation simulator according to the monte carlo method simulates movement of each of neutrons by using a parallel computer. In this case, the system to be processed is divided based on a space region and an energy region to which neutrons belong. Simulation of neutrons in the divided regions is allotted to each of performing devices of the parallel computer. Tarry data and nuclear data of the neutrons in each of the regions are memorized dispersedly to memories of each of the performing devices. A transmission means for simulating the behaviors of the neutrons in the region by each of the performing devices, as well as transmitting the information of the neutrons, when the neutrons are moved to other region, to the performing device in a transported portion are disposed to each of the performing devices. With such procedures, simulation for the neutrons in the allotted region can be conducted with small capacity of memories. (I.S.)

  7. Beam-transport system for high-resolution heavy-ion spectroscopy

    International Nuclear Information System (INIS)

    Roussel, P.; Kashy, E.

    1980-01-01

    A method is given to adjust a beam-transport system to the requirements of high-energy resolution heavy-ion spectroscopy. The results of a test experiment performed on a MP tandem with a 12 C beam are shown. A drastic improvement in energy resolution is obtained for a kinematical factor K=1/p dp/dtheta=0.12 [fr

  8. Bending magnets for the CBA beam-transport line

    Energy Technology Data Exchange (ETDEWEB)

    Thern, R.E.

    1983-01-01

    The beam-transport line from the AGS to CBA requires 68 large bending magnets, consisting of pure dipoles and two types of combined function gradient magnets. All three types were designed with magnetic-field calculation program POISSON, using the same exterior dimensions and coil package. The design goal of +-1% momentum acceptance for the transport line required a wide horizontal aperture, with a much-smaller vertical aperture for economy. Two prototypes of one gradient magnet were built, and a facility constructed to measure them and the later production magnets. Measurements were done using both a long coil and a point coil (Rawson-Lush gaussmeter). Preliminary results show ..delta..B/B < 0.2 x 10/sup -3/, ..delta..G/G < 0.3 x 10/sup -2/, and ..delta..B/sub 2//B < 0.3 x 10/sup -4/ cm/sup -2/ over the beam aperture. Due to end effects, the actual gradient differs from the design gradient by 1%, which has been compensated for in the beam-line design.

  9. High-field superconducting window-frame beam-transport magnets

    International Nuclear Information System (INIS)

    Allinger, J.; Carroll, A.; Danby, G.; DeVito, B.; Jackson, J.; Leonhardt, W.; Prodell, A.; Skarita, J.

    1982-01-01

    The window-frame design for high-field superconducting beam-transport magnets was first applied to two, 2-m-long, 4-T modules of an 8 0 bending magent which has operated for nine years in the primary proton beam line at the Brookhaven National Laboratory Alternating Gradient Synchrotron (AGS). The design of two 1.5-m long, 7.6-cm cold-bore superconducting windowframe magnets, described in this paper, intended for the external proton beam transport system at the AGS incorporated evolutionary changes. These magnets generated a maximum aperture field of 6.8 T with a peak field in the dipole coil of 7.1 T. Measured fields are very accurate and are compared to values calculated using the computer programs LINDA and POISSON. Results of quench-propagation studies demonstrate the excellent thermal stability of the magnets. The magnets quench safely without energy extraction at a maximum current density, J = 130 kA/cm 2 in the superconductor, corresponding to J = 57.6 kA/cm 2 overall the conductor at B = 6.7 T

  10. Optimisation of electron beam characteristics by simulated annealing

    International Nuclear Information System (INIS)

    Ebert, M.A.; University of Adelaide, SA; Hoban, P.W.

    1996-01-01

    Full text: With the development of technology in the field of treatment beam delivery, the possibility of tailoring radiation beams (via manipulation of the beam's phase space) is foreseeable. This investigation involved evaluating a method for determining the characteristics of pure electron beams which provided dose distributions that best approximated desired distributions. The aim is to determine which degrees of freedom are advantageous and worth pursuing in a clinical setting. A simulated annealing routine was developed to determine optimum electron beam characteristics. A set of beam elements are defined at the surface of a homogeneous water equivalent phantom defining discrete positions and angles of incidence, and electron energies. The optimal weighting of these elements is determined by the (generally approximate) solution to the linear equation, Dw = d, where d represents the dose distribution calculated over the phantom, w the vector of (50 - 2x10 4 ) beam element relative weights, and D a normalised matrix of dose deposition kernels. In the iterative annealing procedure, beam elements are randomly selected and beam weighting distributions are sampled and used to perturb the selected elements. Perturbations are accepted or rejected according to standard simulated annealing criteria. The result (after the algorithm has terminated due to meeting an iteration or optimisation specification) is an approximate solution for the beam weight vector (w) specified by the above equation. This technique has been applied for several sample dose distributions and phase space restrictions. An example is given of the phase space obtained when endeavouring to conform to a rectangular 100% dose region with polyenergetic though normally incident electrons. For regular distributions, intuitive conclusions regarding the benefits of energy/angular manipulation may be made, whereas for complex distributions, variations in intensity over beam elements of varying energy and

  11. Monte Carlo Simulation of a Linear Accelerator and Electron Beam Parameters Used in Radiotherapy

    Directory of Open Access Journals (Sweden)

    Mohammad Taghi Bahreyni Toossi

    2009-06-01

    Full Text Available Introduction: In recent decades, several Monte Carlo codes have been introduced for research and medical applications. These methods provide both accurate and detailed calculation of particle transport from linear accelerators. The main drawback of Monte Carlo techniques is the extremely long computing time that is required in order to obtain a dose distribution with good statistical accuracy. Material and Methods: In this study, the MCNP-4C Monte Carlo code was used to simulate the electron beams generated by a Neptun 10 PC linear accelerator. The depth dose curves and related parameters to depth dose and beam profiles were calculated for 6, 8 and 10 MeV electron beams with different field sizes and these data were compared with the corresponding measured values. The actual dosimetry was performed by employing a Welhofer-Scanditronix dose scanning system, semiconductor detectors and ionization chambers. Results: The result showed good agreement (better than 2% between calculated and measured depth doses and lateral dose profiles for all energies in different field sizes. Also good agreements were achieved between calculated and measured related electron beam parameters such as E0, Rq, Rp and R50. Conclusion: The simulated model of the linac developed in this study is capable of computing electron beam data in a water phantom for different field sizes and the resulting data can be used to predict the dose distributions in other complex geometries.

  12. Advances in complexity of beam halo-chaos and its control methods for beam transport networks

    International Nuclear Information System (INIS)

    Fang Jinqing

    2004-11-01

    The complexity theory of beam halo-chaos in beam transport networks and its control methods for a new subject of high-tech field is discussed. It is pointed that in recent years, there has been growing interest in proton beams of high power linear accelerator due to its attractive features in possible breakthrough applications in national defense and industry. In particular, high-current accelerator driven clean activity nuclear power systems for various applications as energy resources has been one of the most focusing issues in the current research, because it provides a safer, cleaner and cheaper nuclear energy resource. However, halo-chaos in high-current beam transport networks become a key concerned issue because it can generate excessive radioactivity therefore significantly limits its applications. It is very important to study the complexity properties of beam halo-chaos and to understand the basic physical mechanisms for halo chaos formation as well as to develop effective control methods for its suppression. These are very challenging subjects for the current research. The main research advances in the subjects, including experimental investigation and the oretical research, especially some very efficient control methods developed through many years of efforts of authors are reviewed and summarized. Finally, some research outlooks are given. (author)

  13. Beam dynamics simulation in the X-ray Compton source

    Energy Technology Data Exchange (ETDEWEB)

    Gladkikh, P.; Karnaukhov, I.; Telegin, Yu.; Shcherbakov, A. E-mail: shcherbakov@kipt.kharkov.ua; Zelinsky, A

    2002-05-01

    At the National Science Center 'Kharkov Institute of Physics and Technology' the X-ray source based on Compton scattering has been developed. The computer code for simulation of electron beam dynamics with taking into account the Compton scattering effect based on Monte Carlo method is described in this report. The first results of computer simulation of beam dynamics with electron-photon interaction, parameters of electron and photon beams are presented. Calculations were carried out with the lattice of synchrotron light source SRS-800 Ukrainian Synchrotron Center.

  14. Longitudinal and transverse space charge limitations on transport of maximum power beams

    International Nuclear Information System (INIS)

    Khoe, T.K.; Martin, R.L.

    1977-01-01

    The maximum transportable beam power is a critical issue in selecting the most favorable approach to generating ignition pulses for inertial fusion with high energy accelerators. Maschke and Courant have put forward expressions for the limits on transport power for quadrupole and solenoidal channels. Included in a more general way is the self consistent effect of space charge defocusing on the power limit. The results show that no limits on transmitted power exist in principal. In general, quadrupole transport magnets appear superior to solenoids except for transport of very low energy and highly charged particles. Longitudinal space charge effects are very significant for transport of intense beams

  15. Studies of heavy ion beam transport in a magnetic quadrupole channel

    International Nuclear Information System (INIS)

    Klabunde, J.; Reiser, M.; Schonlein, A.; Spadtke, P.; Struckmeier, J.

    1983-01-01

    In connection with the West German Heavy Ion Fusion Program the first stage (six periods) of a magnetic quadrupole channel (FODO type) to study the transport of intense ion beams was built at GSI. Different ion beams can be used and the variation of the brightness of these beams (hence of the tune depression sigma/sigma /SUB o/ ) is sufficiently large that regions of theoretically predicted instabilities can be covered. The initial studies are being carried out with a high-brightness beam of 190 keV Ar+ ions and currents of a few mA. Since the pulse length is > 0.5 ms and the pressure is between 10 -6 and 10 -7 torr partial space charge neutralization occurs. Clearing electrodes can be used to remove the electrons from the beam. Results of theoretical studies, measurements of charge neutralization effects and first results of transport experiments are reported

  16. The GEANT4 toolkit capability in the hadron therapy field: simulation of a transport beam line

    International Nuclear Information System (INIS)

    Cirrone, G.A.P.; Cuttone, G.; Di Rosa, F.; Raffaele, L.; Russo, G.; Guatelli, S.; Pia, M.G.

    2006-01-01

    At Laboratori Nazionali del Sud of the Instituto Nazionale di Fisica Nucleare of Catania (Sicily, Italy), the first Italian hadron therapy facility named CATANA (Centro di AdroTerapia ed Applicazioni Nucleari Avanzate) has been realized. Inside CATANA 62 MeV proton beams, accelerated by a superconducting cyclotron, are used for the radiotherapeutic treatments of some types of ocular tumours. Therapy with hadron beams still represents a pioneer technique, and only a few centers worldwide can provide this advanced specialized cancer treatment. On the basis of the experience so far gained, and considering the future hadron-therapy facilities to be developed (Rinecker, Munich Germany, Heidelberg/GSI, Darmstadt, Germany, PSI Villigen, Switzerland, CNAO, Pavia, Italy, Centro di Adroterapia, Catania, Italy) we decided to develop a Monte Carlo application based on the GEANT4 toolkit, for the design, the realization and the optimization of a proton-therapy beam line. Another feature of our project is to provide a general tool able to study the interactions of hadrons with the human tissue and to test the analytical-based treatment planning systems actually used in the routine practice. All the typical elements of a hadron-therapy line, such as diffusers, range shifters, collimators and detectors were modelled. In particular, we simulated the Markus type ionization chamber and a Gaf Chromic film as dosimeters to reconstruct the depth (Bragg peak and Spread Out Bragg Peak) and lateral dose distributions, respectively. We validated our simulated detectors comparing the results with the experimental data available in our facility

  17. The GEANT4 toolkit capability in the hadron therapy field: simulation of a transport beam line

    Science.gov (United States)

    Cirrone, G. A. P.; Cuttone, G.; Di Rosa, F.; Raffaele, L.; Russo, G.; Guatelli, S.; Pia, M. G.

    2006-01-01

    At Laboratori Nazionali del Sud of the Instituto Nazionale di Fisica Nucleare of Catania (Sicily, Italy), the first Italian hadron therapy facility named CATANA (Centro di AdroTerapia ed Applicazioni Nucleari Avanzate) has been realized. Inside CATANA 62 MeV proton beams, accelerated by a superconducting cyclotron, are used for the radiotherapeutic treatments of some types of ocular tumours. Therapy with hadron beams still represents a pioneer technique, and only a few centers worldwide can provide this advanced specialized cancer treatment. On the basis of the experience so far gained, and considering the future hadron-therapy facilities to be developed (Rinecker, Munich Germany, Heidelberg/GSI, Darmstadt, Germany, PSI Villigen, Switzerland, CNAO, Pavia, Italy, Centro di Adroterapia, Catania, Italy) we decided to develop a Monte Carlo application based on the GEANT4 toolkit, for the design, the realization and the optimization of a proton-therapy beam line. Another feature of our project is to provide a general tool able to study the interactions of hadrons with the human tissue and to test the analytical-based treatment planning systems actually used in the routine practice. All the typical elements of a hadron-therapy line, such as diffusers, range shifters, collimators and detectors were modelled. In particular, we simulated the Markus type ionization chamber and a Gaf Chromic film as dosimeters to reconstruct the depth (Bragg peak and Spread Out Bragg Peak) and lateral dose distributions, respectively. We validated our simulated detectors comparing the results with the experimental data available in our facility.

  18. The GEANT4 toolkit capability in the hadron therapy field: simulation of a transport beam line

    Energy Technology Data Exchange (ETDEWEB)

    Cirrone, G.A.P. [Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Via S. Sofia 62, Catania (Italy); Cuttone, G. [Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Via S. Sofia 62, Catania (Italy); Di Rosa, F. [Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Via S. Sofia 62, Catania (Italy); Raffaele, L. [Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Via S. Sofia 62, Catania (Italy); Russo, G. [Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Via S. Sofia 62, Catania (Italy); Guatelli, S. [Istituto Nazionale di Fisica Nucleare, Sezione di Genova, Via Dodecaneso 33, Genova (Italy); Pia, M.G. [Istituto Nazionale di Fisica Nucleare, Sezione di Genova, Via Dodecaneso 33, Genova (Italy)

    2006-01-15

    At Laboratori Nazionali del Sud of the Instituto Nazionale di Fisica Nucleare of Catania (Sicily, Italy), the first Italian hadron therapy facility named CATANA (Centro di AdroTerapia ed Applicazioni Nucleari Avanzate) has been realized. Inside CATANA 62 MeV proton beams, accelerated by a superconducting cyclotron, are used for the radiotherapeutic treatments of some types of ocular tumours. Therapy with hadron beams still represents a pioneer technique, and only a few centers worldwide can provide this advanced specialized cancer treatment. On the basis of the experience so far gained, and considering the future hadron-therapy facilities to be developed (Rinecker, Munich Germany, Heidelberg/GSI, Darmstadt, Germany, PSI Villigen, Switzerland, CNAO, Pavia, Italy, Centro di Adroterapia, Catania, Italy) we decided to develop a Monte Carlo application based on the GEANT4 toolkit, for the design, the realization and the optimization of a proton-therapy beam line. Another feature of our project is to provide a general tool able to study the interactions of hadrons with the human tissue and to test the analytical-based treatment planning systems actually used in the routine practice. All the typical elements of a hadron-therapy line, such as diffusers, range shifters, collimators and detectors were modelled. In particular, we simulated the Markus type ionization chamber and a Gaf Chromic film as dosimeters to reconstruct the depth (Bragg peak and Spread Out Bragg Peak) and lateral dose distributions, respectively. We validated our simulated detectors comparing the results with the experimental data available in our facility.

  19. Space charge compensation on the low energy beam transport of Linac4

    CERN Document Server

    AUTHOR|(SzGeCERN)733270; Scrivens, Richard; Jesus Castillo, Santos

    Part of the upgrade program in the injector chains of the CERN accelerator complex is the replacement of the the proton accelerator Linac2 for the brand new Linac4 which will accelerate H$^-$ and its main goal is to increase the beam intensity in the next sections of the LHC accelerator chain. The Linac4 is now under commissioning and will use several ion sources to produce high intensity unbunched H$^-$ beams with different properties, and the low energy beam transport (LEBT) is the system in charge of match all these different beams to the Radio frequency quadrupole (RFQ). The space charge forces that spread the beam ions apart of each other and cause emittance growth limits the maximum intensity that can be transported in the LEBT, but the space charge of intense unbunched ion beams can be compensated by the generated ions by the impact ionization of the residual gas, which creates a source of secondary particles inside the beam pipe. For negative ion beams, the effect of the beam electric field is to ex...

  20. Beam collimation and transport of laser-accelerated protons by a solenoid field

    Energy Technology Data Exchange (ETDEWEB)

    Harres, K; Alber, I; Guenther, M; Nuernberg, F; Otten, A; Schuetrumpf, J; Roth, M [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Schlossgartenstrasse 9, 64289 Darmstadt (Germany); Tauschwitz, A; Bagnoud, V [GSI - Hemholtzzentrum fur Schwerionenforschung GmbH, Plasmaphysik and PHELIX, Planckstrasse 1, 64291 Darmstadt (Germany); Daido, H; Tampo, M [Photo Medical Research Center, JAEA, 8-1 Umemidai, Kizugawa-city, Kyoto, 619-0215 (Japan); Schollmeier, M, E-mail: k.harres@gsi.d [Sandia National Laboratories, Albuquerque NM 87185 (United States)

    2010-08-01

    A pulsed high field solenoid was used in a laser-proton acceleration experiment to collimate and transport the proton beam that was generated at the irradiation of a flat foil by a high intensity laser pulse. 10{sup 12} particles at an energy of 2.3 MeV could be caught and transported over a distance of more than 240 mm. Strong space charge effects occur, induced by the high field of the solenoid that forces all co-moving electrons down the the solenoid's axis, building up a strong negative space charge that interacts with the proton beam. This leads to an aggregation of the proton beam around the solenoid's axis and therefore to a stronger focusing effect. The collimation and transport of laser-accelerated protons is the first step to provide these unique beams for further applications like post-acceleration by conventional accelerator structures.

  1. Beam collimation and transport of laser-accelerated protons by a solenoid field

    International Nuclear Information System (INIS)

    Harres, K; Alber, I; Guenther, M; Nuernberg, F; Otten, A; Schuetrumpf, J; Roth, M; Tauschwitz, A; Bagnoud, V; Daido, H; Tampo, M; Schollmeier, M

    2010-01-01

    A pulsed high field solenoid was used in a laser-proton acceleration experiment to collimate and transport the proton beam that was generated at the irradiation of a flat foil by a high intensity laser pulse. 10 12 particles at an energy of 2.3 MeV could be caught and transported over a distance of more than 240 mm. Strong space charge effects occur, induced by the high field of the solenoid that forces all co-moving electrons down the the solenoid's axis, building up a strong negative space charge that interacts with the proton beam. This leads to an aggregation of the proton beam around the solenoid's axis and therefore to a stronger focusing effect. The collimation and transport of laser-accelerated protons is the first step to provide these unique beams for further applications like post-acceleration by conventional accelerator structures.

  2. Electron beams and applications

    International Nuclear Information System (INIS)

    Haouat, G.; Couillaud, C.

    1998-01-01

    Studies of the physical properties of the ELSA-linac electron beam are presented. They include measurements of the characteristic beam parameter and analyzes of the beam transport using simulation codes. The aim of these studies is to determine the best conditions for production of intense and very short electron bunches and to optimize the transport of space-charge dominated beams. Precise knowledge of the transport dynamics allows to produce beams with the required characteristics for light production in Free-Electron Laser (FEL), and to give a good description of energy-transfer phenomena between electrons and photons in the wriggler. The particular features of ELSA authorize studies of high-intensity, high-brightness beam properties, especially the halo surrounding the dense core of the electron bunches, which is formed by the space charge effects. It is also shown that the ELSA facility is well suited for the fabrication of very short γ and X-rays sources for applied research in nuclear and plasma physics, or for time response studies of fast detectors. (author)

  3. Cyclotron beam dynamic simulations in MATLAB

    International Nuclear Information System (INIS)

    Karamysheva, G.A.; Karamyshev, O.V.; Lepkina, O.E.

    2008-01-01

    MATLAB is useful for beam dynamic simulations in cyclotrons. Programming in an easy-to-use environment permits creation of models in a short space of time. Advanced graphical tools of MATLAB give good visualization features to created models. The beam dynamic modeling results with an example of two different cyclotron designs are presented. Programming with MATLAB opens wide possibilities of the development of the complex program, able to perform complete block of calculations for the design of the accelerators

  4. Electron beam dynamics in the LIU-30/250 accelerator

    International Nuclear Information System (INIS)

    Vakhrushin, Yu.P.; Kuznetsov, V.S.; Tikhomirov, A.S.

    1989-01-01

    Results of numerical simulation of coherent oscillations of electron beam in the LIU-30/250 accelerating system are presented. Transport systems both with continuous field and the discrete ones are considered. The following conclusions are made: amplitude of coherent oscillations inevitably grows in the real transport channel; the presence of correctors can lead to sufficient losses of beam pulse duration; discrete system is the optimal system for beam transport without sufficient losses. 7 refs.; 3 figs

  5. Transport and acceleration of low-emittance electron beams

    International Nuclear Information System (INIS)

    Henke, H.

    1989-01-01

    Linear accelerators for colliders and for free-electron lasers require beams with both high brightness and low emittance. Their transport and acceleration is limited by single-particle effects originating from injection jitter, from the unavoidable position jitter of components, and from chromaticity. Collective phenomena, essentially due to wake fields acting within the bunch, are most severe in the case of high-frequency structures, i.e. a small aperture. Whilst, in the past, the transverse wake-field effects were believed to be most serious, we know that they can even be beneficial when inducing a corresponding spread in betatron oscillation either by an energy spread along the bunch or by an RF focusing system acting on the bunch scale. This paper evaluates the different effects by simple analytical means after making use of the smooth focusing approximation and the two-particle model. Numerical simulation results are used for verification. 14 refs., 6 figs., 2 tabs

  6. Srna - Monte Carlo codes for proton transport simulation in combined and voxelized geometries

    Directory of Open Access Journals (Sweden)

    Ilić Radovan D.

    2002-01-01

    Full Text Available This paper describes new Monte Carlo codes for proton transport simulations in complex geometrical forms and in materials of different composition. The SRNA codes were developed for three dimensional (3D dose distribution calculation in proton therapy and dosimetry. The model of these codes is based on the theory of proton multiple scattering and a simple model of compound nucleus decay. The developed package consists of two codes: SRNA-2KG and SRNA-VOX. The first code simulates proton transport in combined geometry that can be described by planes and second order surfaces. The second one uses the voxelized geometry of material zones and is specifically adopted for the application of patient computer tomography data. Transition probabilities for both codes are given by the SRNADAT program. In this paper, we will present the models and algorithms of our programs, as well as the results of the numerical experiments we have carried out applying them, along with the results of proton transport simulation obtained through the PETRA and GEANT programs. The simulation of the proton beam characterization by means of the Multi-Layer Faraday Cup and spatial distribution of positron emitters obtained by our program indicate the imminent application of Monte Carlo techniques in clinical practice.

  7. Simulations of Large-Area Electron Beam Diodes

    Science.gov (United States)

    Swanekamp, S. B.; Friedman, M.; Ludeking, L.; Smithe, D.; Obenschain, S. P.

    1999-11-01

    Large area electron beam diodes are typically used to pump the amplifiers of KrF lasers. Simulations of large-area electron beam diodes using the particle-in-cell code MAGIC3D have shown the electron flow in the diode to be unstable. Since this instability can potentially produce a non-uniform current and energy distribution in the hibachi structure and lasing medium it can be detrimental to laser efficiency. These results are similar to simulations performed using the ISIS code.(M.E. Jones and V.A. Thomas, Proceedings of the 8^th) International Conference on High-Power Particle Beams, 665 (1990). We have identified the instability as the so called ``transit-time" instability(C.K. Birdsall and W.B. Bridges, Electrodynamics of Diode Regions), (Academic Press, New York, 1966).^,(T.M. Antonsen, W.H. Miner, E. Ott, and A.T. Drobot, Phys. Fluids 27), 1257 (1984). and have investigated the role of the applied magnetic field and diode geometry. Experiments are underway to characterize the instability on the Nike KrF laser system and will be compared to simulation. Also some possible ways to mitigate the instability will be presented.

  8. Simulating Transient Effects of Pulsed Beams on Beam Intercepting Devices

    CERN Document Server

    Richter, Herta; Noah Messomo, Etam

    2011-01-01

    The development in the physics community towards higher beam power through the possibilities of particle accelerators lead to challenges for the developers of elements which are exposed to effect of particle beams (beam intercepting devices = BIDs). For the design of BIDs, the increasing heat load onto these devices due to energetic and focused beams and - in most cases - their highly pulsed nature has to be taken into account. The physics requirements are sometimes opposed to the current state of the art. As one possibility of many in combining the different aspects for these ambitious demands, two highly developed computer programs, namely FLUKA and ANSYS AUTODYN, were joined for this dissertation. The former is a widely enhanced Monte-Carlo-code which specializes on the interaction of particles with static matter, while the latter is a versatile explicit code for the simulation of highly dynamic processes. Both computer programs were developed intensively over years and are still continuously enhanced in o...

  9. Generation of initial kinetic distributions for simulation of long-pulse charged particle beams with high space-charge intensity

    Directory of Open Access Journals (Sweden)

    Steven M. Lund

    2009-11-01

    Full Text Available Self-consistent Vlasov-Poisson simulations of beams with high space-charge intensity often require specification of initial phase-space distributions that reflect properties of a beam that is well adapted to the transport channel—both in terms of low-order rms (envelope properties as well as the higher-order phase-space structure. Here, we first review broad classes of kinetic distributions commonly in use as initial Vlasov distributions in simulations of unbunched or weakly bunched beams with intense space-charge fields including the following: the Kapchinskij-Vladimirskij (KV equilibrium, continuous-focusing equilibria with specific detailed examples, and various nonequilibrium distributions, such as the semi-Gaussian distribution and distributions formed from specified functions of linear-field Courant-Snyder invariants. Important practical details necessary to specify these distributions in terms of standard accelerator inputs are presented in a unified format. Building on this presentation, a new class of approximate initial kinetic distributions are constructed using transformations that preserve linear focusing, single-particle Courant-Snyder invariants to map initial continuous-focusing equilibrium distributions to a form more appropriate for noncontinuous focusing channels. Self-consistent particle-in-cell simulations are employed to show that the approximate initial distributions generated in this manner are better adapted to the focusing channels for beams with high space-charge intensity. This improved capability enables simulations that more precisely probe intrinsic stability properties and machine performance.

  10. Development of the Transport Class Model (TCM) Aircraft Simulation From a Sub-Scale Generic Transport Model (GTM) Simulation

    Science.gov (United States)

    Hueschen, Richard M.

    2011-01-01

    A six degree-of-freedom, flat-earth dynamics, non-linear, and non-proprietary aircraft simulation was developed that is representative of a generic mid-sized twin-jet transport aircraft. The simulation was developed from a non-proprietary, publicly available, subscale twin-jet transport aircraft simulation using scaling relationships and a modified aerodynamic database. The simulation has an extended aerodynamics database with aero data outside the normal transport-operating envelope (large angle-of-attack and sideslip values). The simulation has representative transport aircraft surface actuator models with variable rate-limits and generally fixed position limits. The simulation contains a generic 40,000 lb sea level thrust engine model. The engine model is a first order dynamic model with a variable time constant that changes according to simulation conditions. The simulation provides a means for interfacing a flight control system to use the simulation sensor variables and to command the surface actuators and throttle position of the engine model.

  11. Full simulation of the beam-related backgrounds at the ILC

    Energy Technology Data Exchange (ETDEWEB)

    Schuetz, Anne [DESY (Germany); KIT (Germany)

    2016-07-01

    The ILC has been proposed as the next machine at the energy frontier and a Technical Design Report was presented in 2012. As part of the site-specific studies to prepare the hosting of the ILC in Japan, the final focus region of the ILC had to be adapted. In this contribution, updated results for the beam-related background as well as new results for the backgrounds originating from the beam dump are presented. The beam-related backgrounds are simulated using GuineaPig and are then propagated through the full simulation of the SiD detector. The impact of various modifications in the final-focus region on the detector occupancies are then evaluated. For the neutron background from the beam dump, the FLUKA simulation suite is used, which is well established for dosimetry and shielding studies. With this program, the effect of the neutrons from the ILC beam dumps on the ILC detectors are studied.

  12. Simulation studies of macroparticles falling into the LHC Proton Beam

    CERN Document Server

    Fuster Martinez, N; Zimmermann, F; Baer, T; Giovannozzi, M; Holzer, E B; Nebot Del Busto, E; Nordt, A; Sapinski, M; Yang, Z

    2011-01-01

    We report updated simulations on the interaction of macroparticles falling from the top of the vacuum chamber into the circulating LHC proton beam. The path and charge state of micron size micro-particles are computed together with the resulting beam losses, which — if high enough — can lead to the local quench of superconducting (SC) magnets. The simulated time evolution of the beam loss is compared with observations in order to constrain some macroparticle parameters. We also discuss the possibility of a “multiple crossing” by the same macroparticle, the effect of a strong dipole field, and the dependence of peak loss rate and loss duration on beam current and on beam size.

  13. Electron beam propagation in the ion-focused and resistive regimes

    International Nuclear Information System (INIS)

    Hubbard, R.F.; Lampe, M.; Fernsler, R.; Slinker, S.P.

    1993-01-01

    Pinched propagation of intense relativistic electron beams occurs in several distinct pressure regimes. In low density gases (∼ 1-100 mtorr), the beam propagates in the ion-focused regime (IFR). The beam ionizes the neutral gas, and plasma electrons are ejected, leaving behind a positive ion column which pinches the beam electrostatically. At gas densities near 1 atm, the beam-generated plasma is resistive and the pinch effect is provided by the self-magnetic field of the beam. Beam transport experiments in both regimes have been performed on the Advanced Test Accelerator (ATA) at Lawrence Livermore National Lab. and on SuperIBEX at the Naval Research Lab. IFR methods have been employed in both experiments to transport the beam prior to injection into the air and to introduce a head-to-tail taper in the beam radius. IFR simulations have shown how the resulting beam radius and emittance profiles are influenced by gas density, chamber dimensions and entrance and exit foils. Beam propagation in dense gas is subject to disruption by the resistive hose instability. However, both experiments and simulations have shown that the emittance variation introduced by IFR transport can substantially reduce the growth of the hose instability. Both experiments have also propagated beams in reduced-density channels. Simulations predict that the channel may in some cases produce a moderate stabilizing and tracking effect arising from plasma currents flowing at the edge of the channel

  14. DART: A simulation code for charged particle beams

    International Nuclear Information System (INIS)

    White, R.C.; Barr, W.L.; Moir, R.W.

    1989-01-01

    This paper presents a recently modified version of the 2-D code, DART, which can simulate the behavior of a beam of charged particles whose trajectories are determined by electric and magnetic fields. This code was originally used to design laboratory-scale and full-scale beam direct converters. Since then, its utility has been expanded to allow more general applications. The simulation includes space charge, secondary electrons, and the ionization of neutral gas. A beam can contain up to nine superimposed beamlets of different energy and species. The calculation of energy conversion efficiency and the method of specifying the electrode geometry are described. Basic procedures for using the code are given, and sample input and output fields are shown. 7 refs., 18 figs

  15. Ant colony algorithm implementation in electron and photon Monte Carlo transport: application to the commissioning of radiosurgery photon beams.

    Science.gov (United States)

    García-Pareja, S; Galán, P; Manzano, F; Brualla, L; Lallena, A M

    2010-07-01

    In this work, the authors describe an approach which has been developed to drive the application of different variance-reduction techniques to the Monte Carlo simulation of photon and electron transport in clinical accelerators. The new approach considers the following techniques: Russian roulette, splitting, a modified version of the directional bremsstrahlung splitting, and the azimuthal particle redistribution. Their application is controlled by an ant colony algorithm based on an importance map. The procedure has been applied to radiosurgery beams. Specifically, the authors have calculated depth-dose profiles, off-axis ratios, and output factors, quantities usually considered in the commissioning of these beams. The agreement between Monte Carlo results and the corresponding measurements is within approximately 3%/0.3 mm for the central axis percentage depth dose and the dose profiles. The importance map generated in the calculation can be used to discuss simulation details in the different parts of the geometry in a simple way. The simulation CPU times are comparable to those needed within other approaches common in this field. The new approach is competitive with those previously used in this kind of problems (PSF generation or source models) and has some practical advantages that make it to be a good tool to simulate the radiation transport in problems where the quantities of interest are difficult to obtain because of low statistics.

  16. Ant colony algorithm implementation in electron and photon Monte Carlo transport: Application to the commissioning of radiosurgery photon beams

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Pareja, S.; Galan, P.; Manzano, F.; Brualla, L.; Lallena, A. M. [Servicio de Radiofisica Hospitalaria, Hospital Regional Universitario ' ' Carlos Haya' ' , Avda. Carlos Haya s/n, E-29010 Malaga (Spain); Unidad de Radiofisica Hospitalaria, Hospital Xanit Internacional, Avda. de los Argonautas s/n, E-29630 Benalmadena (Malaga) (Spain); NCTeam, Strahlenklinik, Universitaetsklinikum Essen, Hufelandstr. 55, D-45122 Essen (Germany); Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Granada, E-18071 Granada (Spain)

    2010-07-15

    Purpose: In this work, the authors describe an approach which has been developed to drive the application of different variance-reduction techniques to the Monte Carlo simulation of photon and electron transport in clinical accelerators. Methods: The new approach considers the following techniques: Russian roulette, splitting, a modified version of the directional bremsstrahlung splitting, and the azimuthal particle redistribution. Their application is controlled by an ant colony algorithm based on an importance map. Results: The procedure has been applied to radiosurgery beams. Specifically, the authors have calculated depth-dose profiles, off-axis ratios, and output factors, quantities usually considered in the commissioning of these beams. The agreement between Monte Carlo results and the corresponding measurements is within {approx}3%/0.3 mm for the central axis percentage depth dose and the dose profiles. The importance map generated in the calculation can be used to discuss simulation details in the different parts of the geometry in a simple way. The simulation CPU times are comparable to those needed within other approaches common in this field. Conclusions: The new approach is competitive with those previously used in this kind of problems (PSF generation or source models) and has some practical advantages that make it to be a good tool to simulate the radiation transport in problems where the quantities of interest are difficult to obtain because of low statistics.

  17. Ant colony algorithm implementation in electron and photon Monte Carlo transport: Application to the commissioning of radiosurgery photon beams

    International Nuclear Information System (INIS)

    Garcia-Pareja, S.; Galan, P.; Manzano, F.; Brualla, L.; Lallena, A. M.

    2010-01-01

    Purpose: In this work, the authors describe an approach which has been developed to drive the application of different variance-reduction techniques to the Monte Carlo simulation of photon and electron transport in clinical accelerators. Methods: The new approach considers the following techniques: Russian roulette, splitting, a modified version of the directional bremsstrahlung splitting, and the azimuthal particle redistribution. Their application is controlled by an ant colony algorithm based on an importance map. Results: The procedure has been applied to radiosurgery beams. Specifically, the authors have calculated depth-dose profiles, off-axis ratios, and output factors, quantities usually considered in the commissioning of these beams. The agreement between Monte Carlo results and the corresponding measurements is within ∼3%/0.3 mm for the central axis percentage depth dose and the dose profiles. The importance map generated in the calculation can be used to discuss simulation details in the different parts of the geometry in a simple way. The simulation CPU times are comparable to those needed within other approaches common in this field. Conclusions: The new approach is competitive with those previously used in this kind of problems (PSF generation or source models) and has some practical advantages that make it to be a good tool to simulate the radiation transport in problems where the quantities of interest are difficult to obtain because of low statistics.

  18. Lattice design of medium energy beam transport line for n spallation neutron source

    International Nuclear Information System (INIS)

    Dhingra, Rinky; Kulkarni, Nita S.; Kumar, Vinit

    2015-01-01

    A 1 GeV H - injector linac is being designed at RRCAT for the proposed Indian Spallation Neutron Source (ISNS). The front-end of the injector linac will consist of Radiofrequency Quadrupole (RFQ) linac, which will accelerate the H - beam from 50 keV to 3 MeV. The beam will be further accelerated in superconducting Single Spoke Resonators (SSRs). A Medium Energy Beam Transport (MEBT) line will be used to transport the beam from the exit of RFQ to the input of SSR. The main purpose of MEBT is to carry out beam matching from RFQ to SSR, and beam chopping. In this paper, we describe the optimization criteria for the lattice design of MEBT. The optimized lattice element parameters are presented for zero and full (15 mA) current case. Beam dynamics studies have been carried out using an envelope tracing code Trace-3D. Required beam deflection angle due to the chopper housed inside the MEBT for beam chopping has also been estimated. (author)

  19. Monitoring beam position in the TRISTAN AR-to-MR transport lines

    International Nuclear Information System (INIS)

    Ieiri, Takao; Arinaga, Mitsuhiro

    1994-01-01

    A beam-position monitor (BPM) has been installed in the transport lines between the Accumulation Ring (AR) and the Main Ring (MR) of TRISTAN. This monitor can detect the beam position and its charge every passage of the beam. Variations of the beam position have been observed during the routine operation. An investigation into the AR extraction components has been carried out in order to clarify a source of the variations. (author)

  20. Transport of a relativistic electron beam through hydrogen gas

    International Nuclear Information System (INIS)

    Haan, P. de.

    1981-01-01

    In this thesis the author describes the transport properties of an electron beam through vacuum and through hydrogen gas with pressure ranging from 25 to 1000 Pa. Maximum beam energy and current are 0.8 MeV and 6 kA, respectively. The pulse length is around 150 ns. A description is given of the experimental device. Also the diagnostics for probing the beam and the plasma, produced by the beam, are discussed, as well as the data acquisition system. The interaction between the beam and hydrogen gas with a pressure around 200 Pa is considered. A plasma with density around 10 19 m -3 is produced within a few nanoseconds. Measurements yield the atomic hydrogen temperature, electron density, beam energy loss, and induced plasma current and these are compared with the results of a model combining gas ionization and dissociation, and turbulent plasma heating. The angular distribution of the beam electrons about the magnetic field axis is discussed. (Auth.)

  1. Experimental investigation of focusing and transport of heavy-current electron beams

    International Nuclear Information System (INIS)

    Baranchikov, E.I.; Gordeev, A.V.; Koba, Yu.V.; Korolev, V.D.; Pen'kina, V.S.; Rudakov, L.I.; Smirnov, V.P.; Sukhov, A.D.; Tarumov, E.Z.

    The results of an experimental and theoretical study of beam transfer through transverse magnetic fields are outlined. The injection and transport of an annular relativistic electron beam due to a magnetic trap of acute-angle geometry are experimentally studied

  2. Modeling beams with elements in phase space

    International Nuclear Information System (INIS)

    Nelson, E.M.

    1998-01-01

    Conventional particle codes represent beams as a collection of macroparticles. An alternative is to represent the beam as a collection of current carrying elements in phase space. While such a representation has limitations, it may be less noisy than a macroparticle model, and it may provide insights about the transport of space charge dominated beams which would otherwise be difficult to gain from macroparticle simulations. The phase space element model of a beam is described, and progress toward an implementation and difficulties with this implementation are discussed. A simulation of an axisymmetric beam using 1d elements in phase space is demonstrated

  3. Quadrupole transport experiment with space charge dominated cesium ion beam

    International Nuclear Information System (INIS)

    Faltens, A.; Keefe, D.; Kim, C.; Rosenblum, S.; Tiefenback, M.; Warwick, A.

    1984-08-01

    The purpose of the experiment is to investigate the beam current transport limit in a long quadrupole-focussed transport channel in the space charge dominated region where the space charge defocussing force is almost as large as the average focussing force of the channel

  4. LTRACK: Beam-transport calculation including wakefield effects

    International Nuclear Information System (INIS)

    Chan, K.C.D.; Cooper, R.K.

    1988-01-01

    LTRACK is a first-order beam-transport code that includes wakefield effects up to quadrupole modes. This paper will introduce the readers to this computer code by describing the history, the method of calculations, and a brief summary of the input/output information. Future plans for the code will also be described

  5. TURTLE with MAD input (Trace Unlimited Rays Through Lumped Elements) -- A computer program for simulating charged particle beam transport systems and DECAY TURTLE including decay calculations

    Energy Technology Data Exchange (ETDEWEB)

    Carey, D.C.

    1999-12-09

    TURTLE is a computer program useful for determining many characteristics of a particle beam once an initial design has been achieved, Charged particle beams are usually designed by adjusting various beam line parameters to obtain desired values of certain elements of a transfer or beam matrix. Such beam line parameters may describe certain magnetic fields and their gradients, lengths and shapes of magnets, spacings between magnetic elements, or the initial beam accepted into the system. For such purposes one typically employs a matrix multiplication and fitting program such as TRANSPORT. TURTLE is designed to be used after TRANSPORT. For convenience of the user, the input formats of the two programs have been made compatible. The use of TURTLE should be restricted to beams with small phase space. The lumped element approximation, described below, precludes the inclusion of the effect of conventional local geometric aberrations (due to large phase space) or fourth and higher order. A reading of the discussion below will indicate clearly the exact uses and limitations of the approach taken in TURTLE.

  6. TURTLE with MAD input (Trace Unlimited Rays Through Lumped Elements) -- A computer program for simulating charged particle beam transport systems and DECAY TURTLE including decay calculations

    International Nuclear Information System (INIS)

    Carey, D.C.

    1999-01-01

    TURTLE is a computer program useful for determining many characteristics of a particle beam once an initial design has been achieved, Charged particle beams are usually designed by adjusting various beam line parameters to obtain desired values of certain elements of a transfer or beam matrix. Such beam line parameters may describe certain magnetic fields and their gradients, lengths and shapes of magnets, spacings between magnetic elements, or the initial beam accepted into the system. For such purposes one typically employs a matrix multiplication and fitting program such as TRANSPORT. TURTLE is designed to be used after TRANSPORT. For convenience of the user, the input formats of the two programs have been made compatible. The use of TURTLE should be restricted to beams with small phase space. The lumped element approximation, described below, precludes the inclusion of the effect of conventional local geometric aberrations (due to large phase space) or fourth and higher order. A reading of the discussion below will indicate clearly the exact uses and limitations of the approach taken in TURTLE

  7. Transoptr-a second order beam transport design code with automatic internal optimization and general constraints

    International Nuclear Information System (INIS)

    Heighway, E.A.

    1980-07-01

    A second order beam transport design code with parametric optimization is described. The code analyzes the transport of charged particle beams through a user defined magnet system. The magnet system parameters are varied (within user defined limits) until the properties of the transported beam and/or the system transport matrix match those properties requested by the user. The code uses matrix formalism to represent the transport elements and optimization is achieved using the variable metric method. Any constraints that can be expressed algebraically may be included by the user as part of his design. Instruction in the use of the program is given. (auth)

  8. OoTran, an object-oriented program for charged-particle beam transport design

    International Nuclear Information System (INIS)

    Ninane, A.; Ferte, J.M.; Mareschal, P.; Sibomana, M.; Somers, F.

    1990-01-01

    The OoTran program is a new object-oriented program for charged-particle beam transport computation. Using a simple menu interface, the user builds his beam line with magnetic and electric elements taken from a standard library. The program computes the beam transport using a well-known first-order matrix formalism and displays 'in real time' the computed beam envelope. The menu editor provides functions to interactively modify the beam line. Ootran is written in C++ and uses two object libraries: OOPS, the Object-Oriented Program Support Class Library, which is a collection of classes similar to those of Smalltalk-80; and InterViews, a C++ graphical-interface toolkit based on the X-Window system. OoTran is running on DECstation 3100, VAXstation 2000 and SUN 3, with the ULTRIX and SUN OS operating systems. (orig.)

  9. Single side damage simulations and detection in beam-like structures

    International Nuclear Information System (INIS)

    Zhou, Yun-Lai; Perera, R; Wahab, M Abdel; Maia, N; Sampaio, R; Figueiredo, E

    2015-01-01

    Beam-like structures are the most common components in real engineering, while single side damage is often encountered. In this study, a numerical analysis of single side damage in a free-free beam is analysed with three different finite element models; namely solid, shell and beam models for demonstrating their performance in simulating real structures. Similar to experiment, damage is introduced into one side of the beam, and natural frequencies are extracted from the simulations and compared with experimental and analytical results. Mode shapes are also analysed with modal assurance criterion. The results from simulations reveal a good performance of the three models in extracting natural frequencies, and solid model performs better than shell while shell model performs better than beam model under intact state. For damaged states, the natural frequencies captured from solid model show more sensitivity to damage severity than shell model and shell model performs similar to the beam model in distinguishing damage. The main contribution of this paper is to perform a comparison between three finite element models and experimental data as well as analytical solutions. The finite element results show a relatively well performance. (paper)

  10. Electron-beam generation, transport, and transverse oscillation experiments using the REX injector

    International Nuclear Information System (INIS)

    Carlson, R.L.; Allison, P.W.; Kauppila, T.J.; Moir, D.C.; Ridlon, R.N.

    1991-01-01

    The REX machine at LANL is being used as a prototype to generate a 4-MV, 4.5-kA, 55-ns flat-top electron beam as a source for injection into a linear induction accelerator of the 16-MeV Dual Axis Radiographic Hydrotest facility. The pulsed-power source drives a planar velvet cathode producing a beam that is accelerated through a foilless anode aperture and transported by an air core magnetic lens for injection into the first 48 linear induction cells. Extensive measurements of the time-resolved (<1-ns) properties of the beam using a streak camera and high-speed electronic diagnostics have been made. These parameters include beam current, voltage, current density, emittance, and transverse beam motion. The effective cathode temperature is 117 eV, corresponding to a Lapostolle emittance of 0.96 mm-rad. Transverse oscillations of the transported beam have been observed via a differenced B-dot technique to be about ±100 μ at 245 MHz. This beam motion has been correlated via detailed rf measurements of asymmetric transverse cavity modes in the A-K gap

  11. Prospects of e-beam evaporated molybdenum oxide as a hole transport layer for perovskite solar cells

    Science.gov (United States)

    Ali, F.; Khoshsirat, N.; Duffin, J. L.; Wang, H.; Ostrikov, K.; Bell, J. M.; Tesfamichael, T.

    2017-09-01

    Perovskite solar cells have emerged as one of the most efficient and low cost technologies for delivering of solar electricity due to their exceptional optical and electrical properties. Commercialization of the perovskite solar cells is, however, limited because of the higher cost and environmentally sensitive organic hole transport materials such as spiro-OMETAD and PEDOT:PSS. In this study, an empirical simulation was performed using the Solar Cell Capacitance Simulator software to explore the MoOx thin film as an alternative hole transport material for perovskite solar cells. In the simulation, properties of MoOx thin films deposited by the electron beam evaporation technique from high purity (99.99%) MoO3 pellets at different substrate temperatures (room temperature, 100 °C and 200 °C) were used as input parameters. The films were highly transparent (>80%) and have low surface roughness (≤2 nm) with bandgap energy ranging between 3.75 eV and 3.45 eV. Device simulation has shown that the MoOx deposited at room temperature can work in both the regular and inverted structures of the perovskite solar cell with a promising efficiency of 18.25%. Manufacturing of the full device is planned in order to utilize the MoOx as an alternative hole transport material for improved performance, good stability, and low cost of the perovskite solar cell.

  12. Transport of dc and bunched beams through a 25 MV folded tandem accelerator

    International Nuclear Information System (INIS)

    Milner, W.T.; Alton, G.D.; Hensley, D.C.; Jones, C.M.; King, R.F.; Larson, J.D.; Moak, C.D.; Sayer, R.O.

    1975-01-01

    Studies of beam transport through the planned ORNL 25 MV folded tandem accelerator demonstrate efficient utilization of phase-space acceptance and the feasibility of injecting bunched beams from the tandem accelerator into the Oak Ridge Isochronous Cyclotron (ORIC). Use of a 180 0 bending magnet in the terminal provides outstanding charge state selection and permits better control of the high-energy beam transport than has previously been possible in conventional tandem accelerators. Time spreads introduced in bunched beams by the 180 0 magnet are kept within a 6 0 RF acceptance window at ORIC provided the beam has a crossover in the center of the 180 0 magnet. Ion masses from 12 to 240 amu, preinjection energies from 150 to 500 keV and terminal voltages from 7.5 to 25 MV were studied for dc beams and beams bunched by various modulation techniques. (U.S.)

  13. Evolution of a beam dynamics model for the transport line in a proton therapy facility

    Science.gov (United States)

    Rizzoglio, V.; Adelmann, A.; Baumgarten, C.; Frey, M.; Gerbershagen, A.; Meer, D.; Schippers, J. M.

    2017-12-01

    During the conceptual design of an accelerator or beamline, first-order beam dynamics models are essential for studying beam properties. However, they can only produce approximate results. During commissioning, these approximate results are compared to measurements, which will rarely coincide if the model does not include the relevant physics. It is therefore essential that this linear model is extended to include higher-order effects. In this paper, the effects of particle-matter interaction have been included in the model of the transport lines in the proton therapy facility at the Paul Scherrer Institut (PSI) in Switzerland. The first-order models of these beamlines provide an approximated estimation of beam size, energy loss and transmission. To improve the performance of the facility, a more precise model was required and has been developed with opal (Object Oriented Parallel Accelerator Library), a multiparticle open source beam dynamics code. In opal, the Monte Carlo simulations of Coulomb scattering and energy loss are performed seamless with the particle tracking. Beside the linear optics, the influence of the passive elements (e.g., degrader, collimators, scattering foils, and air gaps) on the beam emittance and energy spread can be analyzed in the new model. This allows for a significantly improved precision in the prediction of beam transmission and beam properties. The accuracy of the opal model has been confirmed by numerous measurements.

  14. Ion beam properties after mass filtering with a linear radiofrequency quadrupole

    International Nuclear Information System (INIS)

    Ferrer, R.; Kwiatkowski, A.A.; Bollen, G.; Lincoln, D.L.; Morrissey, D.J.; Pang, G.K.; Ringle, R.; Savory, J.; Schwarz, S.

    2014-01-01

    The properties of ion beams passing through a linear radiofrequency quadrupole mass filter were investigated with special attention to their dependence on the mass resolving power. Experimentally, an increase of the transverse emittance was observed as the mass-to-charge selectivity of the mass filter was raised. The experimental behavior was confirmed by beam transport simulations. -- Highlights: • The ion-optical properties of a Quadrupole Mass Filter (QMF) are presented. • Measured beam emittances follow a trend to larger values for smaller A/Q ratios and increasing mass resolution. • The experimental behavior was confirmed by beam transport simulations. • The use of a QMF for mass filtering comes at the cost of emittance growth of the ion beam

  15. Electrostatic design and beam transport for a folded tandem electrostatic quadrupole accelerator facility for accelerator-based boron neutron capture therapy

    International Nuclear Information System (INIS)

    Thatar Vento, V.; Bergueiro, J.; Cartelli, D.; Valda, A.A.; Kreiner, A.J.

    2011-01-01

    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.

  16. A method for photon beam Monte Carlo multileaf collimator particle transport

    Science.gov (United States)

    Siebers, Jeffrey V.; Keall, Paul J.; Kim, Jong Oh; Mohan, Radhe

    2002-09-01

    Monte Carlo (MC) algorithms are recognized as the most accurate methodology for patient dose assessment. For intensity-modulated radiation therapy (IMRT) delivered with dynamic multileaf collimators (DMLCs), accurate dose calculation, even with MC, is challenging. Accurate IMRT MC dose calculations require inclusion of the moving MLC in the MC simulation. Due to its complex geometry, full transport through the MLC can be time consuming. The aim of this work was to develop an MLC model for photon beam MC IMRT dose computations. The basis of the MC MLC model is that the complex MLC geometry can be separated into simple geometric regions, each of which readily lends itself to simplified radiation transport. For photons, only attenuation and first Compton scatter interactions are considered. The amount of attenuation material an individual particle encounters while traversing the entire MLC is determined by adding the individual amounts from each of the simplified geometric regions. Compton scatter is sampled based upon the total thickness traversed. Pair production and electron interactions (scattering and bremsstrahlung) within the MLC are ignored. The MLC model was tested for 6 MV and 18 MV photon beams by comparing it with measurements and MC simulations that incorporate the full physics and geometry for fields blocked by the MLC and with measurements for fields with the maximum possible tongue-and-groove and tongue-or-groove effects, for static test cases and for sliding windows of various widths. The MLC model predicts the field size dependence of the MLC leakage radiation within 0.1% of the open-field dose. The entrance dose and beam hardening behind a closed MLC are predicted within +/-1% or 1 mm. Dose undulations due to differences in inter- and intra-leaf leakage are also correctly predicted. The MC MLC model predicts leaf-edge tongue-and-groove dose effect within +/-1% or 1 mm for 95% of the points compared at 6 MV and 88% of the points compared at 18 MV

  17. A method for photon beam Monte Carlo multileaf collimator particle transport

    Energy Technology Data Exchange (ETDEWEB)

    Siebers, Jeffrey V. [Department of Radiation Oncology, Medical College of Virginia Hospitals, Virginia Commonwealth University, Richmond, VA (United States)]. E-mail: jsiebers@vcu.edu; Keall, Paul J.; Kim, Jong Oh; Mohan, Radhe [Department of Radiation Oncology, Medical College of Virginia Hospitals, Virginia Commonwealth University, Richmond, VA (United States)

    2002-09-07

    Monte Carlo (MC) algorithms are recognized as the most accurate methodology for patient dose assessment. For intensity-modulated radiation therapy (IMRT) delivered with dynamic multileaf collimators (DMLCs), accurate dose calculation, even with MC, is challenging. Accurate IMRT MC dose calculations require inclusion of the moving MLC in the MC simulation. Due to its complex geometry, full transport through the MLC can be time consuming. The aim of this work was to develop an MLC model for photon beam MC IMRT dose computations. The basis of the MC MLC model is that the complex MLC geometry can be separated into simple geometric regions, each of which readily lends itself to simplified radiation transport. For photons, only attenuation and first Compton scatter interactions are considered. The amount of attenuation material an individual particle encounters while traversing the entire MLC is determined by adding the individual amounts from each of the simplified geometric regions. Compton scatter is sampled based upon the total thickness traversed. Pair production and electron interactions (scattering and bremsstrahlung) within the MLC are ignored. The MLC model was tested for 6 MV and 18 MV photon beams by comparing it with measurements and MC simulations that incorporate the full physics and geometry for fields blocked by the MLC and with measurements for fields with the maximum possible tongue-and-groove and tongue-or-groove effects, for static test cases and for sliding windows of various widths. The MLC model predicts the field size dependence of the MLC leakage radiation within 0.1% of the open-field dose. The entrance dose and beam hardening behind a closed MLC are predicted within {+-}1% or 1 mm. Dose undulations due to differences in inter- and intra-leaf leakage are also correctly predicted. The MC MLC model predicts leaf-edge tongue-and-groove dose effect within {+-}1% or 1 mm for 95% of the points compared at 6 MV and 88% of the points compared at 18 MV

  18. Nanodosimetry in a 12C ion beam using Monte Carlo simulations

    International Nuclear Information System (INIS)

    Hultqvist, M.; Lillhoek, J.-E.; Lindborg, L.; Gudowska, I.; Nikjoo, H.

    2010-01-01

    The dose-mean lineal energy, y-bar D , has been calculated in water for irradiation with 12 C ions with initial energies 290 MeV/u. The y-bar D was evaluated from the energy distributions of carbon and secondary boron ions, and from their energy-dependent y-bar D -values. The energy distributions were obtained from simulations with the Monte Carlo code SHIELD-HIT07 and the energy-dependent y-bar D -values were obtained from ion-track simulations with PITS99 coupled with the electron transport code KURBUC. The ratio of the y-bar D -value determined in the vicinity of the Bragg peak to that calculated in a reference 60 Co γ beam was compared with the corresponding ratio of α-values from the linear-quadratic model used in fractionated radiotherapy, showing a good correlation for an object size of around 10 nm.

  19. The ELIMED transport and dosimetry beamline for laser-driven ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Romano, F., E-mail: francesco.romano@lns.infn.it [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Schillaci, F.; Cirrone, G.A.P.; Cuttone, G. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Scuderi, V. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); ELI-Beamlines Project, Institute of Physics ASCR, v.v.i. (FZU), 182 21 Prague (Czech Republic); Allegra, L.; Amato, A.; Amico, A.; Candiano, G.; De Luca, G.; Gallo, G. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Giordanengo, S.; Guarachi, L. Fanola [Istituto Nazionale di Fisica Nucleare, Sezione di Torino, Via P. Giuria 1, Torino (Italy); Universita' di Torino, Dipartimento di Fisica, Via P. Giuria 1, Torino (Italy); Korn, G. [ELI-Beamlines Project, Institute of Physics ASCR, v.v.i. (FZU), 182 21 Prague (Czech Republic); Larosa, G. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Leanza, R. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Universita' di Catania, Dipartimento di Fisica e Astronomia, Via S. Sofia 64, Catania (Italy); Manna, R.; Marchese, V. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Marchetto, F. [Istituto Nazionale di Fisica Nucleare, Sezione di Torino, Via P. Giuria 1, Torino (Italy); Margarone, D. [ELI-Beamlines Project, Institute of Physics ASCR, v.v.i. (FZU), 182 21 Prague (Czech Republic); and others

    2016-09-01

    A growing interest of the scientific community towards multidisciplinary applications of laser-driven beams has led to the development of several projects aiming to demonstrate the possible use of these beams for therapeutic purposes. Nevertheless, laser-accelerated particles differ from the conventional beams typically used for multiscipilinary and medical applications, due to the wide energy spread, the angular divergence and the extremely intense pulses. The peculiarities of optically accelerated beams led to develop new strategies and advanced techniques for transport, diagnostics and dosimetry of the accelerated particles. In this framework, the realization of the ELIMED (ELI-Beamlines MEDical and multidisciplinary applications) beamline, developed by INFN-LNS (Catania, Italy) and that will be installed in 2017 as a part of the ELIMAIA beamline at the ELI-Beamlines (Extreme Light Infrastructure Beamlines) facility in Prague, has the aim to investigate the feasibility of using laser-driven ion beams for multidisciplinary applications. In this contribution, an overview of the beamline along with a detailed description of the main transport elements as well as the detectors composing the final section of the beamline will be presented.

  20. Simulation of electron cloud effects to heavy ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, Fatih; Gjonaj, Erion; Weiland, Thomas [Technische Universitaet Darmstadt (Germany). Institut fuer Theorie Elektromagnetischer Felder

    2011-07-01

    Electron cloud (EC) driven instability can cause beam loss, emittance growth, trajectory change and wake fields. Mentioned crucial effects of EC motivated researchers to understand the EC build up mechanism and the effects of EC to the beam. This motivation also induced the progress of developing new simulation codes. EC simulations can roughly be divided into two classes such as, softwares whose goals are to simulate the build up of the EC during the passage of a bunch train and the codes which model the interaction of a bunch with an EC. The aim of this study is to simulate the effects of electron cloud (EC) on the dynamics of heavy ion beams which are used in heavy ion synchrotron (SIS-18) at GSI. To do this, a 3-D and self-consistent simulation program based on particle in cell (PIC) method is used. In the PIC cycle, accurate solution of the Maxwell equations is obtained by employing discontinuous Galerkin finite element method. As a model, we assumed a perfectly conducting beam pipe which was uniformly (or randomly) loaded with the electrons. Then as parallel with the realistic cases in SIS-18, a single bunch consisting of U{sup +73} ions was extracted which could propagate in this pipe. Due to EC-ion bunch interaction, electrons gained energy and their displacements were observed. Electric and magnetic field components and EC charge density were calculated, numerically.

  1. An analytical simulation technique for cone-beam CT and pinhole SPECT

    International Nuclear Information System (INIS)

    Zhang Xuezhu; Qi Yujin

    2011-01-01

    This study was aimed at developing an efficient simulation technique with an ordinary PC. The work involved derivation of mathematical operators, analytic phantom generations, and effective analytical projectors developing for cone-beam CT and pinhole SPECT imaging. The computer simulations based on the analytical projectors were developed by ray-tracing method for cone-beam CT and voxel-driven method for pinhole SPECT of degrading blurring. The 3D Shepp-Logan, Jaszczak and Defrise phantoms were used for simulation evaluations and image reconstructions. The reconstructed phantom images were of good accuracy with the phantoms. The results showed that the analytical simulation technique is an efficient tool for studying cone-beam CT and pinhole SPECT imaging. (authors)

  2. Modeling and simulation of a proton beam space-charge neutralization

    International Nuclear Information System (INIS)

    Fleury, Xavier

    2000-01-01

    The aim of this work is to understand and to model the build-up of a plasma in the low-energy beam transport line of a proton accelerator. This plasma is generated by the beam, which ionizes the residual gas remaining in this low-energy section. By neutralizing the space-charge of the beam, the plasma modifies its transport, thus, to control the beam, it is necessary to study this phenomenon. In this work, we consider a continuous beam and we take interest in the stationary states of the plasma. We first restrict the description of the plasma to a plane perpendicular to the beam, by assuming that the beam and the plasma are longitudinally invariant. The build-up of the plasma is first described with a kinetic model where binary collisions are neglected, based on the Vlasov-Poisson system with source terms which take into account ionization. We prove mathematically that this system has no stationary solution, by using appropriate subsets of the phase-space that we call trapping-sets. Yet, measurements show that the plasma evolves towards a steady state. To account for this evolution, we modify the source terms of the model. The resulting model is solved by a particle-in-cell method, and the results are compared to the measurements. Then, we show that binary collisions between plasma electrons and beam ions or gas molecules help to maintain the equilibrium of the plasma. In the last part of the thesis, we use hydrodynamic models to investigate more easily the coupling between transversal and longitudinal effects. The preliminary study of a one-dimensional model enables to find the behaviour of the transverse potential of the plasma. Finally, a two-dimensional model of the transport of the beam when it is neutralized by the plasma is solved numerically, which shows that the longitudinal electric field should play an important role in the set-up of the equilibrium of the plasma. (author) [fr

  3. The expert system OPTRAN (Ver 1.0) and its application to beam transportation line design

    International Nuclear Information System (INIS)

    Xiao Meiqin; Lu Hongyou; Fan Mingwu

    1994-01-01

    The expert system OPTRAN (Ver 1.0) used for beam transportation line design is introduced. The knowledge storage and reasoning principle, of which the intelligence part of OPTRAN are composed, have been described in detail. By using OPTRAN (Ver 1.0), the design of a beam transportation line for extracted ion beam of Cyclone 30 was completed

  4. X-ray convergent beam pattern simulation using the Moodie-Wagenfeld equations: 3-beam Laue case

    International Nuclear Information System (INIS)

    Liu, L.; Goodman, P.

    1998-01-01

    Pattern simulations for 3-beam X-ray diffraction are presented, by multi-slice calculations based on Moodie and Wagenfeld's formulation of the X-ray equations, which factorise Maxwell's equations into Dirac format, using circular-polarisation bases. The results are presented in the form of convergent-beam patterns for each diffraction order, using experience gained from CBED (convergent beam electron diffraction) and LACBED (large-angle CBED), since this displays the results in the most compact form. The acronym CBXRAD (convergent-beam X-ray-diffraction) is used for these patterns. Although optics required for the complete patterns is not currently available, capillary focussing is undergoing rapid development, and our simulations define critical angular ranges within reach of current designs. Simulations for light and heavy-atoms structures belonging to the enantiomorphic space-group pair P3 1 21 and P3 2 21, provide clear evidence of chiral interaction between radiation and structure, highlighting divergences from the well studied CBED pattern symmetries. MoKα 1 and TaKα 1 wavelengths were used to minimise absorption for the two structures respectively, although 'anomalous absorption' is always important due to the large thicknesses required (up to 20 mm)

  5. Paul Trap Simulator Experiment (PTSX) to simulate intense beam propagation through a periodic focusing quadrupole field

    International Nuclear Information System (INIS)

    Davidson, Ronald C.; Efthimion, Philip C.; Gilson, Erik; Majeski, Richard; Qin, Hong

    2002-01-01

    The Paul Trap Simulator Experiment (PTSX) is under construction at the Princeton Plasma Physics Laboratory to simulate intense beam propagation through a periodic quadrupole magnetic field. In the Paul trap configuration, a long nonneutral plasma column is confined axially by dc voltages on end cylinders at z=+L and z=-L, and transverse confinement is provided by segmented cylindrical electrodes with applied oscillatory voltages ±V 0 (t) over 90 deg. segments. Because the transverse focusing force is similar in waveform to that produced by a discrete set of periodic quadrupole magnets in a frame moving with the beam, the Paul trap configuration offers the possibility of simulating intense beam propagation in a compact laboratory facility. The experimental layout is described, together with the planned experiments to study beam mismatch, envelope instabilities, halo particle production, and collective wave excitations

  6. Paul Trap Simulator Experiment (PTSX) to simulate intense beam propagation through a periodic focusing quadrupole field

    Science.gov (United States)

    Davidson, Ronald C.; Efthimion, Philip C.; Gilson, Erik; Majeski, Richard; Qin, Hong

    2002-01-01

    The Paul Trap Simulator Experiment (PTSX) is under construction at the Princeton Plasma Physics Laboratory to simulate intense beam propagation through a periodic quadrupole magnetic field. In the Paul trap configuration, a long nonneutral plasma column is confined axially by dc voltages on end cylinders at z=+L and z=-L, and transverse confinement is provided by segmented cylindrical electrodes with applied oscillatory voltages ±V0(t) over 90° segments. Because the transverse focusing force is similar in waveform to that produced by a discrete set of periodic quadrupole magnets in a frame moving with the beam, the Paul trap configuration offers the possibility of simulating intense beam propagation in a compact laboratory facility. The experimental layout is described, together with the planned experiments to study beam mismatch, envelope instabilities, halo particle production, and collective wave excitations.

  7. Beam simulation tools for GEANT4 (and neutrino source applications)

    International Nuclear Information System (INIS)

    V.Daniel Elvira, Paul Lebrun and Panagiotis Spentzouris email daniel@fnal.gov

    2002-01-01

    Geant4 is a tool kit developed by a collaboration of physicists and computer professionals in the High Energy Physics field for simulation of the passage of particles through matter. The motivation for the development of the Beam Tools is to extend the Geant4 applications to accelerator physics. Although there are many computer programs for beam physics simulations, Geant4 is ideal to model a beam going through material or a system with a beam line integrated to a complex detector. There are many examples in the current international High Energy Physics programs, such as studies related to a future Neutrino Factory, a Linear Collider, and a very Large Hadron Collider

  8. Lattice design of beam transport system of FELI

    International Nuclear Information System (INIS)

    Miyauchi, Y.; Koga, A.; Morii, Y.; Sato, S.; Keishi, T.; Tomimasu, T.

    1994-01-01

    A plan of lasing wide range FEL (Free Electron Laser) is in progress at FELI. For this purpose, an S-band linac accelerator system of four output energy levels is under construction. This paper describes the lattice design of its beam transport (BT) system. (author)

  9. DART: a simulation code for charged particle beams

    International Nuclear Information System (INIS)

    White, R.C.; Barr, W.L.; Moir, R.W.

    1988-01-01

    This paper presents a recently modified verion of the 2-D DART code designed to simulate the behavior of a beam of charged particles whose paths are affected by electric and magnetic fields. This code was originally used to design laboratory-scale and full-scale beam direct converters. Since then, its utility has been expanded to allow more general applications. The simulation technique includes space charge, secondary electron effects, and neutral gas ionization. Calculations of electrode placement and energy conversion efficiency are described. Basic operation procedures are given including sample input files and output. 7 refs., 18 figs

  10. An interactive beam line simulator module for RHIC

    International Nuclear Information System (INIS)

    MacKay, W.W.

    1997-01-01

    This paper describes the interactive simulation engine, bl, designed for the RHIC project. The program tracks as output to shared memory the central orbit, Twiss and dispersion functions, as well as the 6 x 6 beam hyperellipsoid. Transfer matrices between elements are available via interactive requests. Using a 6-d model, optical elements are modeled with a linear transfer matrix and a vector. The vector allows simulation of misalignments, shifts in field strengths, and beam rigidity. Currently only a linear model is used for elements. In addition to the usual magnets, a foil element is included which can shift the beam's rigidity (resulting from a change of charge and energy loss), as well as increase the momentum spread and emittance. Running as a Glish client, bl can be interfaced to other programs, such as an orbit plotter and a power supply application to give a quick prediction of the beam orbit from actual operating currents in the accelerator. Various strengths and offsets may be changed by sending Glish events to bl

  11. The Beam Break-Up Numerical Simulator

    International Nuclear Information System (INIS)

    Travish, G.A.

    1989-11-01

    Beam Break-Up (BBU) is a severe constraint in accelerator design, limiting beam current and quality. The control of BBU has become the focus of much research in the design of the next generation collider, recirculating and linear induction accelerators and advanced accelerators. Determining the effect on BBU of modifications to cavities, the focusing elements or the beam is frequently beyond the ability of current analytic models. A computer code was written to address this problem. The Beam Break-Up Numerical Simulator (BBUNS) was designed to numerically solve for beam break-up (BBU) due to an arbitrary transverse wakefield. BBUNS was developed to be as user friendly as possible on the Cray computer series. The user is able to control all aspects of input and output by using a single command file. In addition, the wakefield is specified by the user and read in as a table. The program can model energy variations along and within the beam, focusing magnetic field profiles can be specified, and the graphical output can be tailored. In this note we discuss BBUNS, its structure and application. Included are detailed instructions, examples and a sample session of BBUNS. This program is available for distribution. 50 refs., 18 figs., 5 tabs

  12. A spin-transport system for a longitudinally polarized epithermal neutron beam

    International Nuclear Information System (INIS)

    Crawford, B.E.; Bowman, J.D.; Penttilae, S.I.; Roberson, N.R.

    2001-01-01

    The TRIPLE (Time Reversal and Parity at Low Energies) collaboration uses a polarized epithermal neutron beam and a capture γ-ray detector to study parity violation in neutron-nucleus reactions. In order to preserve the spin polarization of the neutrons as they travel the 60-m path to the target, the beam pipes are wrapped with wire to produce a solenoidal magnetic field of about 10 G along the beam direction. The flanges and bellows between sections of the beam pipe cause gaps in the windings which in turn produce radial fields that can depolarize the neutron spins. A computer code has been developed that numerically evaluates the effect of these gaps on the polarization. A measurement of the neutron depolarization for neutrons in the actual spin-transport system agrees with a calculation of the neutron depolarization for the TRIPLE system. Features that will aid in designing similar spin-transport systems are discussed

  13. Numerical Simulations for the Beam-Induced Electron Cloud in the LHC Beam Screen

    CERN Document Server

    Brüning, Oliver Sim

    1998-01-01

    The following work summarises simulation results obtained at CERN for the beam-induced electron cloud and looks at possible cures for the heat load in the LHC beam screen. The synchrotron radiation in the LHC creates a continuous flow of photoelectrons. These electrons are accelerated by the electric field of the bunch and hit the vacuum chamber on the opposite side of the beam pipe where they crea te secondary electrons which are again accelerated by the next bunch. For a large secondary emission yield the above mechanism leads to an exponential growth of the electron cloud which is limited by space charge forces. The simulations use a two-dimensional mesh for the space charge calculations and include the effect of image charges on the vacuum chamber wall. Depending on the quantum yield for the production of photoelectrons, the secondary emission yield and the reflectivity, the heat load can vary from 0.1 W/m to more than 15 W/m.

  14. Development and validation of a critical gradient energetic particle driven Alfven eigenmode transport model for DIII-D tilted neutral beam experiments

    Science.gov (United States)

    Waltz, R. E.; Bass, E. M.; Heidbrink, W. W.; VanZeeland, M. A.

    2015-11-01

    Recent experiments with the DIII-D tilted neutral beam injection (NBI) varying the beam energetic particle (EP) source profiles have provided strong evidence that unstable Alfven eigenmodes (AE) drive stiff EP transport at a critical EP density gradient [Heidbrink et al 2013 Nucl. Fusion 53 093006]. Here the critical gradient is identified by the local AE growth rate being equal to the local ITG/TEM growth rate at the same low toroidal mode number. The growth rates are taken from the gyrokinetic code GYRO. Simulation show that the slowing down beam-like EP distribution has a slightly lower critical gradient than the Maxwellian. The ALPHA EP density transport code [Waltz and Bass 2014 Nucl. Fusion 54 104006], used to validate the model, combines the low-n stiff EP critical density gradient AE mid-core transport with the Angioni et al (2009 Nucl. Fusion 49 055013) energy independent high-n ITG/TEM density transport model controling the central core EP density profile. For the on-axis NBI heated DIII-D shot 146102, while the net loss to the edge is small, about half the birth fast ions are transported from the central core r/a  <  0.5 and the central density is about half the slowing down density. These results are in good agreement with experimental fast ion pressure profiles inferred from MSE constrained EFIT equilibria.

  15. Monte Carlo simulations of secondary electron emission due to ion beam milling

    Energy Technology Data Exchange (ETDEWEB)

    Mahady, Kyle [Univ. of Tennessee, Knoxville, TN (United States); Tan, Shida [Intel Corp., Santa Clara, CA (United States); Greenzweig, Yuval [Intel Israel Ltd., Haifa (Israel); Livengood, Richard [Intel Corp., Santa Clara, CA (United States); Raveh, Amir [Intel Israel Ltd., Haifa (Israel); Fowlkes, Jason D. [Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Rack, Philip [Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-07-01

    We present a Monte Carlo simulation study of secondary electron emission resulting from focused ion beam milling of a copper target. The basis of this study is a simulation code which simulates ion induced excitation and emission of secondary electrons, in addition to simulating focused ion beam sputtering and milling. This combination of features permits the simulation of the interaction between secondary electron emission, and the evolving target geometry as the ion beam sputters material. Previous ion induced SE Monte Carlo simulation methods have been restricted to predefined target geometries, while the dynamic target in the presented simulations makes this study relevant to image formation in ion microscopy, and chemically assisted ion beam etching, where the relationship between sputtering, and its effects on secondary electron emission, is important. We focus on a copper target, and validate our simulation against experimental data for a range of: noble gas ions, ion energies, ion/substrate angles and the energy distribution of the secondary electrons. We then provide a detailed account of the emission of secondary electrons resulting from ion beam milling; we quantify both the evolution of the yield as high aspect ratio valleys are milled, as well as the emission of electrons within these valleys that do not escape the target, but which are important to the secondary electron contribution to chemically assisted ion induced etching.

  16. Optics of Electron Beam in the Recycler

    International Nuclear Information System (INIS)

    Burov, A.; Kroc, T.; Lebedev, V.; Nagaitsev, S.; Prost, L.; Pruss, S.; Shemyakin, A.; Sutherland, M.; Warner, A.; Kazakevich, G.; Tiunov, M.

    2006-01-01

    Electron cooling of 8.9 GeV/c antiprotons in the Recycler ring (Fermilab) requires high current and good quality of the DC electron beam. Electron trajectories of ∼0.2 A or higher DC electron beam have to be parallel in the cooling section, within ∼ 0.2 mrad, making the beam envelope cylindrical. These requirements yielded a specific scheme of the electron transport from a gun to the cooling section, with electrostatic acceleration and deceleration in the Pelletron. Recuperation of the DC beam limits beam losses at as tiny level as ∼0.001%, setting strict requirements on the return electron line to the Pelletron and a collector. To smooth the beam envelope in the cooling section, it has to be linear and known at the transport start. Also, strength of the relevant optic elements has to be measured with good accuracy. Beam-based optic measurements are being carried out and analysed to get this information. They include beam simulations in the Pelletron, differential optic (beam response) measurements and simulation, beam profile measurements with optical transition radiation, envelope measurements and analysis with orifice scrapers. Current results for the first half-year of commissioning are presented. Although electron cooling is already routinely used for pbar stacking, its efficiency is expected to be improved

  17. SEAWAT-based simulation of axisymmetric heat transport.

    Science.gov (United States)

    Vandenbohede, Alexander; Louwyck, Andy; Vlamynck, Nele

    2014-01-01

    Simulation of heat transport has its applications in geothermal exploitation of aquifers and the analysis of temperature dependent chemical reactions. Under homogeneous conditions and in the absence of a regional hydraulic gradient, groundwater flow and heat transport from or to a well exhibit radial symmetry, and governing equations are reduced by one dimension (1D) which increases computational efficiency importantly. Solute transport codes can simulate heat transport and input parameters may be modified such that the Cartesian geometry can handle radial flow. In this article, SEAWAT is evaluated as simulator for heat transport under radial flow conditions. The 1971, 1D analytical solution of Gelhar and Collins is used to compare axisymmetric transport with retardation (i.e., as a result of thermal equilibrium between fluid and solid) and a large diffusion (conduction). It is shown that an axisymmetric simulation compares well with a fully three dimensional (3D) simulation of an aquifer thermal energy storage systems. The influence of grid discretization, solver parameters, and advection solution is illustrated. Because of the high diffusion to simulate conduction, convergence criterion for heat transport must be set much smaller (10(-10) ) than for solute transport (10(-6) ). Grid discretization should be considered carefully, in particular the subdivision of the screen interval. On the other hand, different methods to calculate the pumping or injection rate distribution over different nodes of a multilayer well lead to small differences only. © 2013, National Ground Water Association.

  18. Centroid motion in periodically focused beams

    International Nuclear Information System (INIS)

    Moraes, J.S.; Pakter, R.; Rizzato, F.B.

    2005-01-01

    The role of the centroid dynamics in the transport of periodically focused particle beams is investigated. A Kapchinskij-Vladimirskij equilibrium distribution for an off-axis beam is derived. It is shown that centroid and envelope dynamics are uncoupled and that unstable regions for the centroid dynamics overlap with previously stable regions for the envelope dynamics alone. Multiparticle simulations validate the findings. The effects of a conducting pipe encapsulating the beam are also investigated. It is shown that the charge induced at the pipe may generate chaotic orbits which can be detrimental to the adequate functioning of the transport mechanism

  19. Electron-beam generation, transport, and transverse oscillation experiments using the REX injector

    International Nuclear Information System (INIS)

    Carlson, R.L.; Allison, P.W.; Kauppila, T.J.; Moir, D.C.; Ridlon, R.N.

    1991-01-01

    The REX machine at LANL is being used as a prototype to generate a 4-MV, 4.5-kA, 55-ns flat-top electron beam as a source for injection into a linear induction accelerator of the 16-MeV Dual-Axis Radiographic Hydrotest facility. The pulsed-power sources drives a planar velvet cathode producing a beam that is accelerated through a foilless anode aperture and transported by an air core magnetic lens for injection into the first of 48 linear induction cells. Extensive measurements of the time-resolved (<1-ns) properties of the beam using a streak camera and high-speed electronic diagnostics have been made. These parameters include beam current, voltage, current density, emittance, and transverse beam motion. The effective cathode temperature is 117 eV, corresponding to a Lapostolle emittance of 0.96 mm-rad. Transverse oscillations of the transported beam have been observed via a differenced B technique to be about ±100 μm at 245 MHz. This beam motion has been correlated via detailed rf measurements of asymmetric transverse cavity modes in the A-K gap. 7 refs., 6 figs

  20. Radial particle distributions in PARMILA simulation beams

    International Nuclear Information System (INIS)

    Boicourt, G.P.

    1984-03-01

    The estimation of beam spill in particle accelerators is becoming of greater importance as higher current designs are being funded. To the present, no numerical method for predicting beam-spill has been available. In this paper, we present an approach to the loss-estimation problem that uses probability distributions fitted to particle-simulation beams. The properties of the PARMILA code's radial particle distribution are discussed, and a broad class of probability distributions are examined to check their ability to fit it. The possibility that the PARMILA distribution is a mixture is discussed, and a fitting distribution consisting of a mixture of two generalized gamma distributions is found. An efficient algorithm to accomplish the fit is presented. Examples of the relative prediction of beam spill are given. 26 references, 18 figures, 1 table

  1. The wondrous world of transport and acceleration of intense ion beams

    International Nuclear Information System (INIS)

    Siebenlist, F.

    1987-01-01

    A theoretical and experimental study of the transport, bunching and acceleration of intense ion beams in periodic focusing channels is described. The aim is to show the feasibility of accelerating high current ion beams with a Multiple Electrostatic Quadrupole Array Linear ACcelerator (MEQALAC). 83 refs.; 51 figs.; 3 tabs

  2. Plans for longitudinal and transverse neutralized beam compression experiments, and initial results from solenoid transport experiments

    International Nuclear Information System (INIS)

    Seidl, P.A.; Armijo, J.; Baca, D.; Bieniosek, F.M.; Coleman, J.; Davidson, R.C.; Efthimion, P.C.; Friedman, A.; Gilson, E.P.; Grote, D.; Haber, I.; Henestroza, E.; Kaganovich, I.; Leitner, M.; Logan, B.G.; Molvik, A.W.; Rose, D.V.; Roy, P.K.; Sefkow, A.B.; Sharp, W.M.; Vay, J.L.; Waldron, W.L.; Welch, D.R.; Yu, S.S.

    2007-01-01

    This paper presents plans for neutralized drift compression experiments, precursors to future target heating experiments. The target-physics objective is to study warm dense matter (WDM) using short-duration (∼1 ns) ion beams that enter the targets at energies just above that at which dE/dx is maximal. High intensity on target is to be achieved by a combination of longitudinal compression and transverse focusing. This work will build upon recent success in longitudinal compression, where the ion beam was compressed lengthwise by a factor of more than 50 by first applying a linear head-to-tail velocity tilt to the beam, and then allowing the beam to drift through a dense, neutralizing background plasma. Studies on a novel pulse line ion accelerator were also carried out. It is planned to demonstrate simultaneous transverse focusing and longitudinal compression in a series of future experiments, thereby achieving conditions suitable for future WDM target experiments. Future experiments may use solenoids for transverse focusing of un-neutralized ion beams during acceleration. Recent results are reported in the transport of a high-perveance heavy ion beam in a solenoid transport channel. The principal objectives of this solenoid transport experiment are to match and transport a space-charge-dominated ion beam, and to study associated electron-cloud and gas effects that may limit the beam quality in a solenoid transport system. Ideally, the beam will establish a Brillouin-flow condition (rotation at one-half the cyclotron frequency). Other mechanisms that potentially degrade beam quality are being studied, such as focusing-field aberrations, beam halo, and separation of lattice focusing elements

  3. Particle-transport simulation with the Monte Carlo method

    International Nuclear Information System (INIS)

    Carter, L.L.; Cashwell, E.D.

    1975-01-01

    Attention is focused on the application of the Monte Carlo method to particle transport problems, with emphasis on neutron and photon transport. Topics covered include sampling methods, mathematical prescriptions for simulating particle transport, mechanics of simulating particle transport, neutron transport, and photon transport. A literature survey of 204 references is included. (GMT)

  4. Experimental investigations of plasma lens focusing and plasma channel transport of heavy ion beams

    International Nuclear Information System (INIS)

    Tauschwitz, T.; Yu, S.S.; Eylon, S.; Reginato, L.; Leemans, W.; Rasmussen, J.O.; Bangerter, R.O.

    1995-04-01

    Final focusing of ion beams and propagation in a reactor chamber are crucial questions for heavy ion beam driven Fusion. An alternative solution to ballistic quadrupole focusing, as it is proposed in most reactor studies today, is the utilization of the magnetic field produced by a high current plasma discharge. This plasma lens focusing concept relaxes the requirements for low emittance and energy spread of the driver beam significantly and allows to separate the issues of focusing, which can be accomplished outside the reactor chamber, and of beam transport inside the reactor. For focusing a tapered wall-stabilized discharge is proposed, a concept successfully demonstrated at GSI, Germany. For beam transport a laser pre-ionized channel can be used

  5. Beam dynamics simulation of W-band photo injector

    International Nuclear Information System (INIS)

    Zhu Xiongwei

    2002-01-01

    The authors present a beam dynamics simulation study on 1.6 cell, high gradient W-Band photocathode RF gun which is capable of generating and accelerating 300 pC electron bunch. The design system is made up of 91.392 GHz photocathode RF gun and 91.392 GHz travelling wave linac cells. Based on the numerical simulation using SUPERFISH and PARMELA and the conventional RF linac scaling law, the design will produce 300 pC at 1.74 MeV with bunch length 0.72 ps and normalized transverse emittance 0.55 mm mrad. The authors study the beam dynamics in high frequency and high gradient; due to the high gradient, the ponderomotive effect plays an important role in beam dynamics; the authors found the ponderomotive effect still exist with only the fundamental space harmonics (synchrotron mode) due to the coupling of the transverse and longitudinal motion

  6. Advanced methods for the computation of particle beam transport and the computation of electromagnetic fields and beam-cavity interactions

    International Nuclear Information System (INIS)

    Dragt, A.J.; Gluckstern, R.L.

    1992-11-01

    The University of Maryland Dynamical Systems and Accelerator Theory Group carries out research in two broad areas: the computation of charged particle beam transport using Lie algebraic methods and advanced methods for the computation of electromagnetic fields and beam-cavity interactions. Important improvements in the state of the art are believed to be possible in both of these areas. In addition, applications of these methods are made to problems of current interest in accelerator physics including the theoretical performance of present and proposed high energy machines. The Lie algebraic method of computing and analyzing beam transport handles both linear and nonlinear beam elements. Tests show this method to be superior to the earlier matrix or numerical integration methods. It has wide application to many areas including accelerator physics, intense particle beams, ion microprobes, high resolution electron microscopy, and light optics. With regard to the area of electromagnetic fields and beam cavity interactions, work is carried out on the theory of beam breakup in single pulses. Work is also done on the analysis of the high frequency behavior of longitudinal and transverse coupling impedances, including the examination of methods which may be used to measure these impedances. Finally, work is performed on the electromagnetic analysis of coupled cavities and on the coupling of cavities to waveguides

  7. Impact of beam transport method on chamber and driver design for heavy ion inertial fusion energy

    Energy Technology Data Exchange (ETDEWEB)

    Rose, D.V.; Welch, D.R.; Olson, C.L.; Yu, S.S.; Neff, S.; Sharp, W.M.

    2002-12-01

    In heavy ion inertial fusion energy systems, intense beams of ions must be transported from the exit of the final focus magnet system through the target chamber to hit millimeter spot sizes on the target. In this paper, we examine three different modes of beam propagation: neutralized ballistic transport, assisted pinched transport, and self-pinched transport. The status of our understanding of these three modes is summarized, and the constraints imposed by beam propagation upon the chamber environment, as well as their compatibility with various chamber and target concepts, are considered. We conclude that, on the basis of our present understanding, there is a reasonable range of parameter space where beams can propagate in thick-liquid wall, wetted-wall, and dry-wall chambers.

  8. Simulation of Electron Beam Trajectory of Thermionic Electron Gun Type with Pierce Electrode

    International Nuclear Information System (INIS)

    Suprapto; Djoko-SP; Djasiman

    2000-01-01

    The simulation of electron beam trajectory for electron gun of electron beam machine has been done. The simulation is carried out according to mechanical design of the electron gun. The simulation is carried out by using the software made by Andrzej Soltan Institute for Nuclear Studies, Swierk-Poland. The result obtained from simulation is approximately parallel electron beam trajectory of 20 mA beam current at 0.66 kV anode voltage, 15 mm cathode-anode distance and 67.5 o cathode angle. Arrangement of electron gun and accelerating tube with 15 kV voltage between anode and the first electrode of accelerating tube yields focus distance of 34 mm from the to cathode. To obtain the approximately parallel beam trajectory which has -0.03 o entrance angles to accelerating tube, the suitable cathode-anode voltage is 12.66 kV. With the entrance angle of -0.03 o it is expected that the electron beam can be accelerated and the beam profile has a small divergence after passing the accelerating tube. (author)

  9. Electromagnetic computer simulations of collective ion acceleration by a relativistic electron beam

    International Nuclear Information System (INIS)

    Galvez, M.; Gisler, G.R.

    1988-01-01

    A 2.5 electromagnetic particle-in-cell computer code is used to study the collective ion acceleration when a relativistic electron beam is injected into a drift tube partially filled with cold neutral plasma. The simulations of this system reveals that the ions are subject to electrostatic acceleration by an electrostatic potential that forms behind the head of the beam. This electrostatic potential develops soon after the beam is injected into the drift tube, drifts with the beam, and eventually settles to a fixed position. At later times, this electrostatic potential becomes a virtual cathode. When the permanent position of the electrostatic potential is at the edge of the plasma or further up, then ions are accelerated forward and a unidirectional ion flow is obtained otherwise a bidirectional ion flow occurs. The ions that achieve higher energy are those which drift with the negative potential. When the plasma density is varied, the simulations show that optimum acceleration occurs when the density ratio between the beam (n b ) and the plasma (n o ) is unity. Simulations were carried out by changing the ion mass. The results of these simulations corroborate the hypothesis that the ion acceleration mechanism is purely electrostatic, so that the ion acceleration depends inversely on the charge particle mass. The simulations also show that the ion maximum energy increased logarithmically with the electron beam energy and proportional with the beam current

  10. Beam control and diagnostic functions in the NIF transport spatial filter

    International Nuclear Information System (INIS)

    Holdener, F.R.; Ables, E.; Bliss, E.S.

    1996-10-01

    Beam control and diagnostic systems are required to align the National Ignition Facility (NIF) laser prior to a shot as well as to provide diagnostics on 192 beam lines at shot time. A design that allows each beam's large spatial filter lenses to also serve as objective lenses for beam control and diagnostic sensor packages helps to accomplish the task at a reasonable cost. However, this approach also causes a high concentration of small optics near the pinhole plane of the transport spatial filter (TSF) at the output of each beam. This paper describes the optomechanical design in and near the central vacuum vessel of the TSF

  11. Neutralization principles for the Extraction and Transport of Ion Beams

    CERN Document Server

    Riege, H

    2000-01-01

    The strict application of conventional extraction techniques of ion beams from a plasma source is characterized by a natural intensity limit determined by space charge.The extracted current may be enhanced far beyond this limit by neutralizing the space charge of the extracted ions in the first extraction gap of the source with electrons injected from the opposite side. The transverse and longitudinal emittances of a neutralized ion beam, hence its brightness, are preserved. Results of beam compensation experiments, which have been carried out with a laser ion source, are resumed for proposing a general scheme of neutralizing ion sources and their adjacent low-energy beam transport channels with electron beams. Many technical applications of high-mass ion beam neutralization technology may be identified: the enhancement of ion source output for injection into high-intensity, low-and high-energy accelerators, or ion thrusters in space technology, for the neutral beams needed for plasma heating of magnetic conf...

  12. Special relativity in beam trajectory simulation in small accelerators

    International Nuclear Information System (INIS)

    Pramudita Anggraita; Budi Santosa; Taufik; Emy Mulyani; Frida Iswinning Diah

    2012-01-01

    Calculation for trajectory simulation of particle beam in small accelerators should account special relativity effect in the beam motion, which differs between parallel and perpendicular direction to the beam velocity. For small electron beam machine of 300 keV, the effect shows up as the rest mass of electron is only 511 keV. Neglecting the effect yields wrong kinetic energy after 300 kV of dc acceleration. For a 13 MeV PET (positron emission tomography) baby cyclotron accelerating proton beam, the effect increases the proton mass by about 1.4% at the final energy. To keep the beam isochronous with the accelerating radiofrequency, a radial increase of the average magnetic field must be designed accordingly. (author)

  13. 3D electromagnetic simulation of spatial autoresonance acceleration of electron beams

    International Nuclear Information System (INIS)

    Dugar-Zhabon, V D; Orozco, E A; González, J D

    2016-01-01

    The results of full electromagnetic simulations of the electron beam acceleration by a TE 112 linear polarized electromagnetic field through Space Autoresonance Acceleration mechanism are presented. In the simulations, both the self-sustaned electric field and selfsustained magnetic field produced by the beam electrons are included into the elaborated 3D Particle in Cell code. In this system, the space profile of the magnetostatic field maintains the electron beams in the acceleration regime along their trajectories. The beam current density evolution is calculated applying the charge conservation method. The full magnetic field in the superparticle positions is found by employing the trilinear interpolation of the mesh node data. The relativistic Newton-Lorentz equation presented in the centered finite difference form is solved using the Boris algorithm that provides visualization of the beam electrons pathway and energy evolution. A comparison between the data obtained from the full electromagnetic simulations and the results derived from the motion equation depicted in an electrostatic approximation is carried out. It is found that the self-sustained magnetic field is a factor which improves the resonance phase conditions and reduces the beam energy spread. (paper)

  14. SNOW: a digital computer program for the simulation of ion beam devices

    International Nuclear Information System (INIS)

    Boers, J.E.

    1980-08-01

    A digital computer program, SNOW, has been developed for the simulation of dense ion beams. The program simulates the plasma expansion cup (but not the plasma source itself), the acceleration region, and a drift space with neutralization if desired. The ion beam is simulated by computing representative trajectories through the device. The potentials are simulated on a large rectangular matrix array which is solved by iterative techniques. Poisson's equation is solved at each point within the configuration using space-charge densities computed from the ion trajectories combined with background electron and/or ion distributions. The simulation methods are described in some detail along with examples of both axially-symmetric and rectangular beams. A detailed description of the input data is presented

  15. Intense electron-beam transport in the ion-focused regime through the collision-dominated regime

    International Nuclear Information System (INIS)

    Sanford, T.W.L.; Poukey, J.W.; Welch, D.R.; Mock, R.C.

    1993-01-01

    This paper reviews the transport of the 19-MeV, 700-kA, 25-ns Hermes-III electron beam in long gas cells filled with N 2 gas spanning six decades in pressure from 10 3 to ∼10 3 Torr. We show through measurements and theoretical analyses that the beam has two windows of stable transport: a low-pressure window (between ∼1 and ∼100 mTorr) that is dominated by propagation in the semi-collisionless IFR (ion-focused regime), and a high-pressure window (between ∼1 and ∼100 Torr) that is dominated by propagation in the resistive CDR (collision-dominated regime). In the CDR, 79±1.5% of the beam energy is transported over 11 m at 20 Torr. In the IFR, we show that intense radiation fields with controllable rise times and pulse widths can be generated on axis at a bremsstrahlung target. In summary, the measurements and analyses presented here provide a quantitative description of the Hermes-III beam transport over six decades in pressure

  16. Measurement and simulation of the TRR BNCT beam parameters

    Energy Technology Data Exchange (ETDEWEB)

    Bavarnegin, Elham [Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of); Department of Physics, University of Guilan, Rasht (Iran, Islamic Republic of); Sadremomtaz, Alireza [Department of Physics, University of Guilan, Rasht (Iran, Islamic Republic of); Khalafi, Hossein [Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of); Kasesaz, Yaser, E-mail: ykasesaz@aeoi.org.ir [Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of); Golshanian, Mohadeseh; Ghods, Hossein; Ezzati, Arsalan; Keyvani, Mehdi; Haddadi, Mohammad [Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of)

    2016-09-11

    Recently, the configuration of the Tehran Research Reactor (TRR) thermal column has been modified and a proper thermal neutron beam for preclinical Boron Neutron Capture Therapy (BNCT) has been obtained. In this study, simulations and experimental measurements have been carried out to identify the BNCT beam parameters including the beam uniformity, the distribution of the thermal neutron dose, boron dose, gamma dose in a phantom and also the Therapeutic Gain (TG). To do this, the entire TRR structure including the reactor core, pool, the thermal column and beam tubes have been modeled using MCNPX Monte Carlo code. To measure in-phantom dose distribution a special head phantom has been constructed and foil activation techniques and TLD700 dosimeter have been used. The results show that there is enough uniformity in TRR thermal BNCT beam. TG parameter has the maximum value of 5.7 at the depth of 1 cm from the surface of the phantom, confirming that TRR thermal neutron beam has potential for being used in treatment of superficial brain tumors. For the purpose of a clinical trial, more modifications need to be done at the reactor, as, for example design, and construction of a treatment room at the beam exit which is our plan for future. To date, this beam is usable for biological studies and animal trials. There is a relatively good agreement between simulation and measurement especially within a diameter of 10 cm which is the dimension of usual BNCT beam ports. This relatively good agreement enables a more precise prediction of the irradiation conditions needed for future experiments.

  17. Simulation of adiabatic thermal beams in a periodic solenoidal magnetic focusing field

    Directory of Open Access Journals (Sweden)

    T. J. Barton

    2012-12-01

    Full Text Available Self-consistent particle-in-cell simulations are performed to verify earlier theoretical predictions of adiabatic thermal beams in a periodic solenoidal magnetic focusing field [K. R. Samokhvalova, J. Zhou, and C. Chen, Phys. Plasmas 14, 103102 (2007PHPAEN1070-664X10.1063/1.2779281; J. Zhou, K. R. Samokhvalova, and C. Chen, Phys. Plasmas 15, 023102 (2008PHPAEN1070-664X10.1063/1.2837891]. In particular, results are obtained for adiabatic thermal beams that do not rotate in the Larmor frame. For such beams, the theoretical predictions of the rms beam envelope, the conservations of the rms thermal emittances, the adiabatic equation of state, and the Debye length are verified in the simulations. Furthermore, the adiabatic thermal beam is found be stable in the parameter regime where the simulations are performed.

  18. Enhanced long-distance transport of periodic electron beams in an advanced double layer cone-channel target

    Directory of Open Access Journals (Sweden)

    Yanling Ji

    2018-02-01

    Full Text Available An enhanced long-distance transport of periodic electron beams in an advanced double layer cone-channel target is investigated using two-dimensional particle-in-cell simulations. The target consists of a cone attached to a double-layer hollow channel with a near-critical-density inner layer. The periodic electron beams are generated by the combination of ponderomotive force and longitudinal laser electric field. Then a stable electron propagation is achieved in the double-layer channel over a much longer distance without evident divergency, compared with a normal cone-channel target. Detailed simulations show that the much better long-distance collimation and guidance of energetic electrons is attributed to the much stronger electromagnetic fields at the inner wall surfaces. Furthermore, a continuous electron acceleration is obtained by the more intense laser electric fields and extended electron acceleration length in the channel. Our investigation shows that by employing this advanced target, both the forward-going electron energy flux in the channel and the energy coupling efficiency from laser to electrons are about threefold increased in comparison with the normal case.

  19. Enhanced long-distance transport of periodic electron beams in an advanced double layer cone-channel target

    Science.gov (United States)

    Ji, Yanling; Duan, Tao; Zhou, Weimin; Li, Boyuan; Wu, Fengjuan; Zhang, Zhimeng; Ye, Bin; Wang, Rong; Wu, Chunrong; Tang, Yongjian

    2018-02-01

    An enhanced long-distance transport of periodic electron beams in an advanced double layer cone-channel target is investigated using two-dimensional particle-in-cell simulations. The target consists of a cone attached to a double-layer hollow channel with a near-critical-density inner layer. The periodic electron beams are generated by the combination of ponderomotive force and longitudinal laser electric field. Then a stable electron propagation is achieved in the double-layer channel over a much longer distance without evident divergency, compared with a normal cone-channel target. Detailed simulations show that the much better long-distance collimation and guidance of energetic electrons is attributed to the much stronger electromagnetic fields at the inner wall surfaces. Furthermore, a continuous electron acceleration is obtained by the more intense laser electric fields and extended electron acceleration length in the channel. Our investigation shows that by employing this advanced target, both the forward-going electron energy flux in the channel and the energy coupling efficiency from laser to electrons are about threefold increased in comparison with the normal case.

  20. Plasma transport simulation modelling for helical confinement systems

    International Nuclear Information System (INIS)

    Yamazaki, K.; Amano, T.

    1992-01-01

    New empirical and theoretical transport models for helical confinement systems are developed on the basis of the neoclassical transport theory, including the effect of the radial electric field and of multi-helicity magnetic components as well as the drift wave turbulence transport for electrostatic and electromagnetic modes or the anomalous semi-empirical transport. These electron thermal diffusivities are compared with experimental data from the Compact Helical System which indicate that the central transport coefficient of a plasma with electron cyclotron heating agrees with neoclassical axisymmetric value and the transport outside the half-radius is anomalous. On the other hand, the transport of plasmas with neutral beam injection heating is anomalous in the whole plasma region. This anomaly is not explained by the electrostatic drift wave turbulence models in these discharges with flat density profiles. For a detailed prediction of the plasma parameters in the Large Helical Device (LHD), 3-D equilibrium/1-D transport simulations including empirical or drift wave turbulence models are performed which suggest that the global confinement time of the LHD is determined mainly by the electron anomalous transport in the plasma edge region rather than by the helical ripple transport in the core region. Even if the ripple loss can be eliminated, the increase in global confinement is 10%. However, the rise in the central ion temperature is more than 20%. If the anomalous loss can be reduced to half of the value used in the present scaling, as is the case in the H-mode of tokamak discharges, the neoclassical ripple loss through the ion channel becomes important even in the plasma core. The 5% radial inward shift of the plasma column with respect to the major radius improves the plasma confinement and increases the fusion product by more than 50% by reducing the neoclassical asymmetric ion transport loss and increasing the plasma radius (10%). (author). 32 refs, 7 figs

  1. FEM simulation of static loading test of the Omega beam

    Science.gov (United States)

    Bílý, Petr; Kohoutková, Alena; Jedlinský, Petr

    2017-09-01

    The paper deals with a FEM simulation of static loading test of the Omega beam. Omega beam is a precast prestressed high-performance concrete element with the shape of Greek letter omega. Omega beam was designed as a self-supporting permanent formwork member for construction of girder bridges. FEM program ATENA Science was exploited for simulation of load-bearing test of the beam. The numerical model was calibrated using the data from both static loading test and tests of material properties. Comparison of load-displacement diagrams obtained from the experiment and the model was conducted. Development of cracks and crack patterns were compared. Very good agreement of experimental data and the FEM model was reached. The calibrated model can be used for design of optimized Omega beams in the future without the need of expensive loading tests. The calibrated material model can be also exploited in other types of FEM analyses of bridges constructed with the use of Omega beams, such as limit state analysis, optimization of shear connectors, prediction of long-term deflections or prediction of crack development.

  2. Simulation of the electron acoustic instability for a finite-size electron beam system

    International Nuclear Information System (INIS)

    Lin, C.S.; Winske, D.

    1987-01-01

    Satellite observations at midlatitudes (≅20,000 km) near the earth's dayside polar cusp boundary layer indicate that the upward electron beams have a narrow latitudinal width up to 0.1 0 . In the cusp boundary layer where the electron population consists of a finite-size electron beam in a background of uniform cold and hot electrons, the electron acoustic mode is unstable inside the electron beam but damped outside the electron beam. Simulations of the electron acoustic instability for a finite-size beam system are carried out with a particle-in-cell code to investigate the heating phenomena associated with the instability and the width of the heating region. The simulations show that the finite-size electron beam radiates electrostatic electron acoustic waves. The decay length of the electron acoustic waves outside the beam in the simulation agrees with the spatial decay length derived from the linear dispersion equation

  3. Kinetic plasma simulation of ion beam extraction from an ECR ion source

    International Nuclear Information System (INIS)

    Elliott, S.M.; White, E.K.; Simkin, J.

    2012-01-01

    Designing optimized ECR (electron cyclotron resonance) ion beam sources can be streamlined by the accurate simulation of beam optical properties in order to predict ion extraction behavior. The complexity of these models, however, can make PIC-based simulations time-consuming. In this paper, we first describe a simple kinetic plasma finite element simulation of extraction of a proton beam from a permanent magnet hexapole ECR ion source. Second, we analyze the influence of secondary electrons generated by ion collisions in the residual gas on the space charge of a proton beam of a dual-solenoid ECR ion source. The finite element method (FEM) offers a fast modeling environment, allowing analysis of ion beam behavior under conditions of varying current density, electrode potential, and gas pressure. The new version of SCALA/TOSCA v14 permits the making of simulations in tens of minutes to a few hours on standard computer platforms without the need of particle-in-cell methods. The paper is followed by the slides of the presentation. (authors)

  4. Beam transport of PF 2.5-GeV electron linac. 2

    International Nuclear Information System (INIS)

    Shiraga, T.; Tamiya, K.; Asami, A.; Suwada, T.; Furukawa, K.; Kamitani, T.; Kobayashi, H.

    1994-01-01

    It was continued to study how to correct the beam transport system of the above linac when a klystron became off. It was shown that the correction could be successfully applied by adjusting the focussing strength of Q-magnets simply in proportion to the beam energy difference produced by the switched off klystron. (author)

  5. Progress on Beam-Plasma Effect Simulations in Muon Ionization Cooling Lattices

    Energy Technology Data Exchange (ETDEWEB)

    Ellison, James [IIT, Chicago; Snopok, Pavel [Fermilab

    2017-05-01

    New computational tools are essential for accurate modeling and simulation of the next generation of muon-based accelerators. One of the crucial physics processes specific to muon accelerators that has not yet been simulated in detail is beam-induced plasma effect in liquid, solid, and gaseous absorbers. We report here on the progress of developing the required simulation tools and applying them to study the properties of plasma and its effects on the beam in muon ionization cooling channels.

  6. Simulations of beam trajectory for position target optimization of extraction system output beams cyclotron proton Decy-13

    International Nuclear Information System (INIS)

    Idrus Abdul Kudus; Taufik

    2015-01-01

    Positioning and track simulation beam the cyclotron Decy-13 for laying optimization the target system have been done using lorentz force function and scilab 5.4.1 simulation. Magnetic field and electric field is calculated using Opera3D/Tosca as a simulation input. Used radio frequency is 77.66 MHz with the amplitude voltage is 40 kV is obtained energy 13 MeV. The result showed that the coordinates of the laying of the target system in a vacuum chamber is located at x = -389 mm and y = 445 mm with the width of the output beam is 10 mm. The laying stripper position for the output in center target is located at x = -76 mm and y =416 mm from the center coordinate on the center of dee with the energy of proton is 13 MeV at the point of beam extraction carbon foil. The changes position laying is carried out on range x = -70; y = 424 mm until x = - 118; y = 374 mm result for shifting area stripper which is still capable of deflection the electron beam. (author)

  7. Beam Optics for Typical Part of ISOL Beam Lines

    International Nuclear Information System (INIS)

    Jang, Ji Ho; Kwon, Hyeok Jung; Kim, Han Sung; Cho, Yong Sub

    2013-01-01

    KOMAC (Korea Multi-purpose Accelerator Complex) is doing a project, the detailed design of the ISOL beam lines for the heavy ion accelerator project of IBS (Institute of Basic Science) from August 2013 to February 2014. The heavy ion beams are transported by using the electrostatic quadrupoles and electrostatic benders between the equipment. The work-scope of the project is the beam optics design of the beam lines and the detailed design of the beam optics components, the electrostatic quadrupoles and the electrostatic bender. This work summarized the initial result of beam optics design of the beam line. We performed the beam optics simulation in two regions of ISOL beam lines and found that beam envelope is less than 2 cm. We will check that the poletip file values are reasonable or not in near future, and we also applied this method to the other parts of the ISOL beam line and optimize them. The result will be used the detailed design of the electrostatic quadrupoles and benders

  8. Impact of Hypobarism During Simulated Transport on Critical Care Air Transport Team Performance

    Science.gov (United States)

    2017-04-26

    AFRL-SA-WP-SR-2017-0008 Impact of Hypobarism During Simulated Transport on Critical Care Air Transport Team Performance Dina...July 2014 – November 2016 4. TITLE AND SUBTITLE Impact of Hypobarism During Simulated Transport on Critical Care Air Transport Team Performance 5a...During Critical Care Air Transport Team Advanced Course validation, three-member teams consisting of a physician, nurse, and respiratory therapist

  9. TRACK The New Beam Dynamics Code

    CERN Document Server

    Mustapha, Brahim; Ostroumov, Peter; Schnirman-Lessner, Eliane

    2005-01-01

    The new ray-tracing code TRACK was developed* to fulfill the special requirements of the RIA accelerator systems. The RIA lattice includes an ECR ion source, a LEBT containing a MHB and a RFQ followed by three SC linac sections separated by two stripping stations with appropriate magnetic transport systems. No available beam dynamics code meet all the necessary requirements for an end-to-end simulation of the RIA driver linac. The latest version of TRACK was used for end-to-end simulations of the RIA driver including errors and beam loss analysis.** In addition to the standard capabilities, the code includes the following new features: i) multiple charge states ii) realistic stripper model; ii) static and dynamic errors iii) automatic steering to correct for misalignments iv) detailed beam-loss analysis; v) parallel computing to perform large scale simulations. Although primarily developed for simulations of the RIA machine, TRACK is a general beam dynamics code. Currently it is being used for the design and ...

  10. Simulation Package based on Placet

    CERN Document Server

    D'Amico, T E; Leros, Nicolas; Schulte, Daniel

    2001-01-01

    The program PLACET is used to simulate transverse and longitudinal beam effects in the main linac, the drive-beam accelerator and the drive-beam decelerators of CLIC, as well as in the linac of CTF3. It provides different models of accelerating and decelerating structures, linear optics and thin multipoles. Several methods of beam-based alignment, including emittance tuning bumps and feedback, and different failure modes can be simulated. An interface to the beam-beam simulation code GUINEA-PIG exists. Currently, interfaces to MAD and TRANSPORT are under development and an extension to transfer lines and bunch compressors is also being made. In the future, the simulations will need to be performed by many users, which requires a simplified user interface. The paper describes the status of PLACET and plans for the futur

  11. Parallel Finite Element Particle-In-Cell Code for Simulations of Space-charge Dominated Beam-Cavity Interactions

    International Nuclear Information System (INIS)

    Candel, A.; Kabel, A.; Ko, K.; Lee, L.; Li, Z.; Limborg, C.; Ng, C.; Prudencio, E.; Schussman, G.; Uplenchwar, R.

    2007-01-01

    Over the past years, SLAC's Advanced Computations Department (ACD) has developed the parallel finite element (FE) particle-in-cell code Pic3P (Pic2P) for simulations of beam-cavity interactions dominated by space-charge effects. As opposed to standard space-charge dominated beam transport codes, which are based on the electrostatic approximation, Pic3P (Pic2P) includes space-charge, retardation and boundary effects as it self-consistently solves the complete set of Maxwell-Lorentz equations using higher-order FE methods on conformal meshes. Use of efficient, large-scale parallel processing allows for the modeling of photoinjectors with unprecedented accuracy, aiding the design and operation of the next-generation of accelerator facilities. Applications to the Linac Coherent Light Source (LCLS) RF gun are presented

  12. On setting magnets in the PEP beam-transport line

    International Nuclear Information System (INIS)

    Peterson, J.M.

    1979-01-01

    This paper discusses magnets in the PEP beam-transport line. Topics discussed are: conditioning, direction of excitation, rate of excitation; determination of the excitation current for the principal bend magnets; steering mechanisms; bump magnets; and determination of excitation currents of the quadrupole magnets

  13. Simulation of effects of incident beam condition in p-p elastic scattering

    International Nuclear Information System (INIS)

    Yu Lei; Zhang Gaolong; Le Xiaoyun; Tanihata, I.

    2014-01-01

    The simulation is performed for the monitors of beam direction and beam position for p-p elastic scattering. We set several variables to simulate the monitors of incident beam condition changes: beam positions at the quadrupole magnet and target in beam line polarimeter (BLP2), distance between quadrupole magnet and target, size of plastic scintillators, distance between the target in BLP2 and the centers of plastic scintillators, and beam polarization. Through the rotation of the coordinate system, the distributions of scattered and recoiled protons in the laboratory system were obtained. By analyzing the count yields in plastic scintillators at different beam positions, we found that the beam incident angular change (0.35°) could be detected when the asymmetry of geometries of left and right scintillators in BLP2 was changed by 6%. Therefore, the scattering angle measured in the experiment can be tracked by these monitors. (authors)

  14. Research into 2D Dynamics and Control of Small Oscillations of a Cross-Beam during Transportation by Two Overhead Cranes

    Directory of Open Access Journals (Sweden)

    Alexander V. Perig

    2017-01-01

    Full Text Available A new mathematical model of a 3DOF 2D mechanical system “transported cross-beam, two moving bridge cranes” has been proposed. Small system oscillations have been derived through the introduction of Lagrange equations. The numerical estimation of 3DOF system motion has been carried out with equation-based Modelica language. The present article uses the Lagrange method and numerical and optimization methods, realized with JModelica.org and Optimica freeware. The absolute swaying of the cross-beam with respect to the displacement of the two moving bridge cranes was estimated. The phase portraits of the 3DOF system for linear and angular coordinates were presented. An open loop optimal control problem was posed for the motion of the bridge cranes. A “bang-bang” control strategy was implemented for the derivation of an optimal control solution, which enables the travel of two bridge cranes at a prescribed distance for minimum time and minimum swaying of a heavy cross-beam. The derived results of the numerical simulation can be easily practically realized by crane operators with good agreement with simple engineering estimations. The proposed control strategy enables synchronous motion of two bridge cranes with a cross-beam that practically solves the posed problem of unwanted excessive oscillations of a heavy cross-beam during transportation.

  15. SU-D-BRC-01: An Automatic Beam Model Commissioning Method for Monte Carlo Simulations in Pencil-Beam Scanning Proton Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Qin, N; Shen, C; Tian, Z; Jiang, S; Jia, X [UT Southwestern Medical Ctr, Dallas, TX (United States)

    2016-06-15

    Purpose: Monte Carlo (MC) simulation is typically regarded as the most accurate dose calculation method for proton therapy. Yet for real clinical cases, the overall accuracy also depends on that of the MC beam model. Commissioning a beam model to faithfully represent a real beam requires finely tuning a set of model parameters, which could be tedious given the large number of pencil beams to commmission. This abstract reports an automatic beam-model commissioning method for pencil-beam scanning proton therapy via an optimization approach. Methods: We modeled a real pencil beam with energy and spatial spread following Gaussian distributions. Mean energy, and energy and spatial spread are model parameters. To commission against a real beam, we first performed MC simulations to calculate dose distributions of a set of ideal (monoenergetic, zero-size) pencil beams. Dose distribution for a real pencil beam is hence linear superposition of doses for those ideal pencil beams with weights in the Gaussian form. We formulated the commissioning task as an optimization problem, such that the calculated central axis depth dose and lateral profiles at several depths match corresponding measurements. An iterative algorithm combining conjugate gradient method and parameter fitting was employed to solve the optimization problem. We validated our method in simulation studies. Results: We calculated dose distributions for three real pencil beams with nominal energies 83, 147 and 199 MeV using realistic beam parameters. These data were regarded as measurements and used for commission. After commissioning, average difference in energy and beam spread between determined values and ground truth were 4.6% and 0.2%. With the commissioned model, we recomputed dose. Mean dose differences from measurements were 0.64%, 0.20% and 0.25%. Conclusion: The developed automatic MC beam-model commissioning method for pencil-beam scanning proton therapy can determine beam model parameters with

  16. Transverse centroid oscillations in solenoidially focused beam transport lattices

    International Nuclear Information System (INIS)

    Lund, Steven M.; Wootton, Christopher J.; Lee, Edward P.

    2009-01-01

    Transverse centroid oscillations are analyzed for a beam in a solenoid transport lattice. Linear equations of motion are derived that describe small-amplitude centroid oscillations induced by displacement and rotational misalignments of the focusing solenoids in the transport lattice, dipole steering elements, and initial centroid offset errors. These equations are analyzed in a local rotating Larmor frame to derive complex-variable 'alignment functions' and 'bending functions' that efficiently describe the characteristics of the centroid oscillations induced by both mechanical misalignments of the solenoids and dipole steering elements. The alignment and bending functions depend only on the properties of the ideal lattice in the absence of errors and steering, and have associated expansion amplitudes set by the misalignments and steering fields, respectively. Applications of this formulation are presented for statistical analysis of centroid oscillations, calculation of actual lattice misalignments from centroid measurements, and optimal beam steering.

  17. Simulation on a limited angle beam gamma ray tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Bum; Jung, Sung Hee; Moon, Jin Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-10-15

    Limited angle beam tomography was introduced in the medical field more than two decades ago, where it was mainly used for cardiovascular diagnostics. Later, it was also used to trace multiphase flows. In these studies, the detection systems were fixed and a scanning electron beam was rapidly swept across an xray target using deflection coils. Thus very fast scanning was possible in these studies, but their geometry resulted in a heavy and bulky system because of a complex control system and vacuum tube. Because of its heavy hardware, limited angle beam tomography has remained as indoor equipment. If the source section is replaced by a gamma ray source, limited angle beam tomography will have a very light source device. In addition, limited angle beam tomography with a gamma ray source can be designed using an open type portable gantry because it does not need a vacuum guide for an electron beam. There is a lot of need for a portable tomographic system but so far no definitive solution has been created. The inspection of industrial on-line pipes, wood telephone poles, and cultural assets are some application areas. This study introduces limited angle beam gamma ray tomography, its simulation, and image reconstruction results. Image reconstruction was performed on the virtual experimental data from a Monte Carlo simulation. Image reconstruction algorithms that are known to be useful for limited angle data were applied and their results compared

  18. Electrostatic design and beam transport for a folded tandem electrostatic quadrupole accelerator facility for accelerator-based boron neutron capture therapy.

    Science.gov (United States)

    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. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Computer simulations of electromagnetic cool ion beam instabilities. [in near earth space

    Science.gov (United States)

    Gary, S. P.; Madland, C. D.; Schriver, D.; Winske, D.

    1986-01-01

    Electromagnetic ion beam instabilities driven by cool ion beams at propagation parallel or antiparallel to a uniform magnetic field are studied using computer simulations. The elements of linear theory applicable to electromagnetic ion beam instabilities and the simulations derived from a one-dimensional hybrid computer code are described. The quasi-linear regime of the right-hand resonant ion beam instability, and the gyrophase bunching of the nonlinear regime of the right-hand resonant and nonresonant instabilities are examined. It is detected that in the quasi-linear regime the instability saturation is due to a reduction in the beam core relative drift speed and an increase in the perpendicular-to-parallel beam temperature; in the nonlinear regime the instabilities saturate when half the initial beam drift kinetic energy density is converted to fluctuating magnetic field energy density.

  20. Numerical Simulation and Mechanical Design for TPS Electron Beam Position Monitors

    Science.gov (United States)

    Hsueh, H. P.; Kuan, C. K.; Ueng, T. S.; Hsiung, G. Y.; Chen, J. R.

    2007-01-01

    Comprehensive study on the mechanical design and numerical simulation for the high resolution electron beam position monitors are key steps to build the newly proposed 3rd generation synchrotron radiation research facility, Taiwan Photon Source (TPS). With more advanced electromagnetic simulation tool like MAFIA tailored specifically for particle accelerator, the design for the high resolution electron beam position monitors can be tested in such environment before they are experimentally tested. The design goal of our high resolution electron beam position monitors is to get the best resolution through sensitivity and signal optimization. The definitions and differences between resolution and sensitivity of electron beam position monitors will be explained. The design consideration is also explained. Prototype deign has been carried out and the related simulations were also carried out with MAFIA. The results are presented here. Sensitivity as high as 200 in x direction has been achieved in x direction at 500 MHz.

  1. Numerical Simulation and Mechanical Design for TPS Electron Beam Position Monitors

    International Nuclear Information System (INIS)

    Hsueh, H. P.; Kuan, C. K.; Ueng, T. S.; Hsiung, G. Y.; Chen, J. R.

    2007-01-01

    Comprehensive study on the mechanical design and numerical simulation for the high resolution electron beam position monitors are key steps to build the newly proposed 3rd generation synchrotron radiation research facility, Taiwan Photon Source (TPS). With more advanced electromagnetic simulation tool like MAFIA tailored specifically for particle accelerator, the design for the high resolution electron beam position monitors can be tested in such environment before they are experimentally tested. The design goal of our high resolution electron beam position monitors is to get the best resolution through sensitivity and signal optimization. The definitions and differences between resolution and sensitivity of electron beam position monitors will be explained. The design consideration is also explained. Prototype deign has been carried out and the related simulations were also carried out with MAFIA. The results are presented here. Sensitivity as high as 200 in x direction has been achieved in x direction at 500 MHz

  2. Beam-transport optimization for cold-neutron spectrometer

    Directory of Open Access Journals (Sweden)

    Nakajima Kenji

    2015-01-01

    Full Text Available We report the design of the beam-transport system (especially the vertical geometry for a cold-neutron disk-chopper spectrometer AMATERAS at J-PARC. Based on the elliptical shape, which is one of the most effective geometries for a ballistic mirror, the design was optimized to obtain, at the sample position, a neutron beam with high flux without serious degrading in divergence and spacial homogeneity within the boundary conditions required from actual spectrometer construction. The optimum focal point was examined. An ideal elliptical shape was modified to reduce its height without serious loss of transmission. The final result was adapted to the construction requirements of AMATERAS. Although the ideas studied in this paper are considered for the AMATERAS case, they can be useful also to other spectrometers in similar situations.

  3. MCMEG: Simulations of both PDD and TPR for 6 MV LINAC photon beam using different MC codes

    International Nuclear Information System (INIS)

    Fonseca, T.C.F.; Mendes, B.M.; Lacerda, M.A.S.; Silva, L.A.C.; Paixão, L.

    2017-01-01

    The Monte Carlo Modelling Expert Group (MCMEG) is an expert network specializing in Monte Carlo radiation transport and the modelling and simulation applied to the radiation protection and dosimetry research field. For the first inter-comparison task the group launched an exercise to model and simulate a 6 MV LINAC photon beam using the Monte Carlo codes available within their laboratories and validate their simulated results by comparing them with experimental measurements carried out in the National Cancer Institute (INCA) in Rio de Janeiro, Brazil. The experimental measurements were performed using an ionization chamber with calibration traceable to a Secondary Standard Dosimetry Laboratory (SSDL). The detector was immersed in a water phantom at different depths and was irradiated with a radiation field size of 10×10 cm 2 . This exposure setup was used to determine the dosimetric parameters Percentage Depth Dose (PDD) and Tissue Phantom Ratio (TPR). The validation process compares the MC calculated results to the experimental measured PDD20,10 and TPR20,10. Simulations were performed reproducing the experimental TPR20,10 quality index which provides a satisfactory description of both the PDD curve and the transverse profiles at the two depths measured. This paper reports in detail the modelling process using MCNPx, MCNP6, EGSnrc and Penelope Monte Carlo codes, the source and tally descriptions, the validation processes and the results. - Highlights: • MCMEG is an expert network specializing in Monte Carlo radiation transport. • MCNPx, MCNP6, EGSnrc and Penelope Monte Carlo codes are used. • Exercise to model and simulate a 6 MV LINAC photon beam using the Monte Carlo codes. • The PDD 20,10 and TPR 20,10 dosimetric parameters were compared with real data. • The paper reports in the modelling process using different Monte Carlo codes.

  4. Simulations relevant to the beam instability in the foreshock

    International Nuclear Information System (INIS)

    Cairns, I.H.; Nishikawa, K.I.

    1989-01-01

    Electrons backstreaming into Earth's foreshock generate waves near the plasma frequency f p by the beam instability. Tow versions of the beam instability exist: the reactive version, in which narrow-band waves grow by bunching the electrons in space, and the kinetic version, in which broadband growth occurs by a maser mechanism. Recently, it has been suggested that (1) the backstreaming electrons have steep-sided cutoff distributions which are initially unstable to the reactive instability, (2) the back reaction to the wave growth causes the instability to pass into its kinetic phase, and (3) the kinetic instability saturates by quasi-linear relaxation. In this paper the authors present two-dimensional simulations of the reactive instability for Maxwellian beams and cutoff distributions. They demonstrate that the reactive instability is a bunching instability and that the reactive instability saturates and passes over into the kinetic phase by particle trapping.A reactive/kinetic transition is shown to most likely occur within 1 km and 50 km of the bow shock. They suggest that the frequency of the intense narrow-band waves decrease from above f p to perhaps 0.9f p (dependent on the beam density) with increasing penetration into the high beam speed region of the foreshock, before the wave frequency rises again as the waves become broadband deeper in the foreshock. Both the simulation results and numerical solutions of the dispersion equation indicate that for the observed beam parameters the center frequency of the waves near the foreshock boundary should be between 0.9f p and 0.98f p , rather than above f p as previously believed. The simulation results indicate that the effects of spatial inhomogeneity are vital for a quantitative understanding of the foreshock waves

  5. Monte Carlo simulation of small field electron beams for small animal irradiation

    International Nuclear Information System (INIS)

    Lee, Chung-Chi; Chen, Ai-Mei; Tung, Chuan-Jong; Chao, Tsi-Chian

    2011-01-01

    The volume effect of detectors in the dosimetry of small fields for photon beams has been well studied due to interests in radiosurgery and small beamlets used in IMRT treatments; but there is still an unexplored research field for small electron beams used in small animal irradiation. This study proposes to use the BEAM Monte Carlo (MC) simulation to assess characteristics of small electron beams (4, 6, 14, 30 mm in diameter) with the kinetic energies of 6 and 18 MeV. Three factors influencing beam characteristics were studied (1) AE and ECUT settings, (2) photon jaw settings and (3) simulation pixel sizes. Study results reveal that AE/ECUT settings at 0.7 MeV are adequate for linear accelerator treatment head simulation, while 0.521 MeV is more favorable to be used for the phantom study. It is also demonstrated that voxel size setting at 1/4 of the simulation field width in all directions is sufficient to achieve accurate results. As for the photon jaw setting, it has great impact on the absolute output of different field size setting (i.e. output factor) but with minimum effect on the relative lateral distribution.

  6. Beam Delivery Simulation: BDSIM - Development & Optimization

    CERN Document Server

    Nevay, Laurence James; Garcia-Morales, H; Gibson, S M; Kwee-Hinzmann, R; Snuverink, J; Deacon, L C

    2014-01-01

    Beam Delivery Simulation (BDSIM) is a Geant4 and C++ based particle tracking code that seamlessly tracks particles through accelerators and detectors, including the full range of particle interaction physics processes from Geant4. BDSIM has been successfully used to model beam loss and background conditions for many current and future linear accelerators such as the Accelerator Test Facility 2 (ATF2) and the International Linear Collider (ILC). Current developments extend its application for use with storage rings, in particular for the Large Hadron Collider (LHC) and the High Luminosity upgrade project (HL-LHC). This paper presents the latest results from using BDSIM to model the LHC as well as the developments underway to improve performance.

  7. Progress Toward Source-to-Target Simulation

    International Nuclear Information System (INIS)

    Grote, D.P.; Friedman, A.; Craig, G.D.; Sharp, W.M.; Haber, I.

    2000-01-01

    Source-to-target simulation of an accelerator provides a thorough check on the consistency of the design as well as a detailed understanding of the beam behavior. Issues such as envelope mis-match and emittance growth can be examined in a self-consistent manner, including the details of accelerator transitions, long-term transport, and longitudinal compression. The large range in scales, from centimeter-scale transverse beam size and applied field scale-length, to meter-scale beam length, to kilometer-scale accelerator length, poses a significant computational challenge. The ever-increasing computational power that is becoming available through massively parallel computers is making such simulation realizable. This paper discusses the progress toward source-to-target simulation using the WARP particle-in-cell code. Representative examples are shown, including 3-D, along-term transport simulations of Integrated Research Experiment (IRE) scale accelerators

  8. Numerical simulation on beam breakup unstability of linear induction accelerator

    International Nuclear Information System (INIS)

    Zhang Kaizhi; Wang Huacen; Lin Yuzheng

    2003-01-01

    A code is written to simulate BBU in induction linac according to theoretical analysis. The general form of evolution of BBU in induction linac is investigated at first, then the effect of related parameters on BBU is analyzed, for example, the alignment error, oscillation frequency of beam centroid, beam pulse shape and acceleration gradient. At last measures are put forward to damp beam breakup unstability (BBU)

  9. Computer simulations of anomalous transport

    International Nuclear Information System (INIS)

    Lee, W.W.; Okuda, H.

    1980-07-01

    Numerical plasma simulations have been carried out to study: (1) the turbulent spectrum and anomalous plasma transport associated with a steady state electrostatic drift turbulence; and (2) the anomalous energy transport of electrons due to shear-Alfven waves in a finite-β plasma. For the simulation of the steady state drift turbulence, it is observed that, in the absence of magnetic shear, the turbulence is quenched to a low level when the rotational transform is a rational number, while the turbulent level remains high for an irrational rotational transform

  10. Effect of flexural crack on plain concrete beam failure mechanism A numerical simulation

    Directory of Open Access Journals (Sweden)

    Abdoullah Namdar

    2016-03-01

    Full Text Available The flexural failure of plain concrete beam occurs along with development of flexural crack on beam. In this paper by using ABAQUS, mechanism failure of plain concrete beam under three steps have been simulated. The cracking moment has been analytically calculated and applied on the both sides of the fixed beam, and flexural crack has been simulated on beam. Displacement, von Mises, load reaction, displacementcrack length, von Mises-crack length and von Mises-displacement of beams have been graphical depicted. Results indicated that, the flexural crack governs beam mechanism failure and its effects on beam resistance failure. It has been found that the flexural crack in initial stage it developed slowly and changes to be fast at the final stage of collapsing beam due to reduction of the flexural resistance of beam. Increasing mechanical properties of concrete, collapse displacement is reduced.

  11. Beam Dynamics Simulations of the REX-ISOLDE A/q-separator

    CERN Document Server

    Fraser, M A; Wenander, F

    2014-01-01

    The REX-ISOLDE A=q-separator selects the radioactive species of interest from the background of residual gas ions coming from the EBIS ion source. In the context of the HIE-ISOLDE upgrade, including the implementation of a multi-harmonic buncher and an upgraded EBIS, the separator and the beam line between the EBIS and RFQ, which we will call the Low Energy Beam Transfer (LEBT) line, has been simulated by tracking particles through the field maps of each active element using the TRACK [4] code. The simulations were benchmarked with a COSY-1 model that was improved to take into account the fringe fields of the electrostatic quadrupoles, electrostatic deflector and magnetic bender; the model can be used to tune and optimise the separator with higher-order effects taken into account. In this note the beam dynamics simulations are documented and the transverse and longitudinal acceptance of the separator line studied to provide design constraints for the EBIS upgrade.

  12. Electromagnetic design and development of a combined function horizontal and vertical dipole steerer magnet for medium energy beam transport line

    International Nuclear Information System (INIS)

    Singh, Kumud; Itteera, Janvin; Ukarde, Priti; Teotia, Vikas; Kumar, Prashant; Malhotra, Sanjay; Taly, Y.K.

    2013-01-01

    Medium Energy Beam Transport (MEBT) line is required to match the optical functions between the RFQ and SRF cavities/DTL cavities.The primary function of the MEBT lines is to keep the emittance growth of the output beam as low as possible in a highly space charge environment at low energies. The transverse focusing of the beam is achieved by strong focusing quadrupoles and the longitudinal dynamics is achieved by the buncher cavities. The Dipole Steerers serve the function of a control element to achieve the desired transverse beam position. To minimize the emittance growth high magnetic field rigidity is required in a highly constrained longitudinal space for these corrector magnets. The design and development of an air-cooled dipole steerer magnet has been done for an integral dipole field of 2.1mT-m in a Good Field Region (GFR) of 23 mm diameter with Integral Field homogeneity better than 0.5%. Electromagnetic field simulations were done using 3D-FEM simulation software OPERA. Error sensitivity studies have been carried out to specify the manufacturing tolerances to estimate and minimize the beam transmission loss due to likely misalignments and rotation of the magnet. A combined function dipole corrector magnet has been designed and fabricated at the Control Instrumentation Division, BARC. This paper discusses measurement results of a combined function dipole steerer for MEBT line for Proton (H + ) beam at 2.5 MeV. (author)

  13. Simulations of multistage intense ion beam acceleration

    International Nuclear Information System (INIS)

    Slutz, S.A.; Poukey, J.W.

    1992-01-01

    An analytic theory for magnetically insulated, multistage acceleration of high intensity ion beams, where the diamagnetic effect due to electron flow is important, has been presented by Slutz and Desjarlais. The theory predicts the existence of two limiting voltages called V 1 (W) and V 2 (W), which are both functions of the injection energy qW of ions entering the accelerating gap. As the voltage approaches V 1 (W), unlimited beam-current density can penetrate the gap without the formation of a virtual anode because the dynamic gap goes to zero. Unlimited beam current density can penetrate an accelerating gap above V 2 (W), although a virtual anode is formed. It was found that the behavior of these limiting voltages is strongly dependent on the electron density profile. The authors have investigated the behavior of these limiting voltages numerically using the 2-D particle-in-cell (PIC) code MAGIC. Results of these simulations are consistent with the superinsulated analytic results. This is not surprising, since the ignored coordinate eliminates instabilities known to be important from studies of single stage magnetically insulated ion diodes. To investigate the effect of these instabilities the authors have simulated the problem with the 3-D PIC code QUICKSILVER, which indicates behavior that is consistent with the saturated model

  14. RIA Beam Dynamics Comparing TRACK to IMPACT

    CERN Document Server

    Mustapha, Brahim; Ostroumov, Peter; Qiang, Ji; Ryne, Robert D

    2005-01-01

    In order to benchmark the newly developed beam dynamics code TRACK we have performed comparisons with well established existing codes. During code development, codes like TRANSPORT, COSY, GIOS and RAYTRACE were used to check TRACK's implementation of the different beam line elements. To benchmark the end-to-end simulation of the RIA driver linac, the simulation of the low-energy part (from the ion source to the entrance of the SC linac) was compared with PARMTEQ and found to agree well. For the simulation of the SC linac the code IMPACT is used. Prior to these simulations, the code IMPACT had to be updated to meet the special requirements of the RIA driver linac. Features such as multiple charge state acceleration, stripper simulation and beam collimation were added to the code. IMPACT was also modified to support new types of rf cavities and to include fringe fields for all the elements. This paper will present a comparison of the beam dynamics simulation in the RIA driver linac between the codes TRACK and I...

  15. Improved alternating gradient transport and focusing of neutral molecules

    International Nuclear Information System (INIS)

    Kalnins, Juris; Lambertson, Glen; Gould, Harvey

    2001-01-01

    Polar molecules, in strong-field seeking states, can be transported and focused by an alternating sequence of electric field gradients that focus in one transverse direction while defocusing in the other. We show by calculation and numerical simulation, how one may greatly improve the alternating gradient transport and focusing of molecules. We use a new optimized multipole lens design, a FODO lattice beam transport line, and lenses to match the beam transport line to the beam source and the final focus. We derive analytic expressions for the potentials, fields, and gradients that may be used to design these lenses. We describe a simple lens optimization procedure and derive the equations of motion for tracking molecules through a beam transport line. As an example, we model a straight beamline that transports a 560 m/s jet-source beam of methyl fluoride molecules 15 m from its source and focuses it to 2 mm diameter. We calculate the beam transport line acceptance and transmission, for a beam with velocity spread, and estimate the transmitted intensity for specified source conditions. Possible applications are discussed

  16. Focal spot size predictions for beam transport through a gas-filled reactor

    International Nuclear Information System (INIS)

    Yu, S.S.; Lee, E.P.; Buchanan, H.L.

    1980-01-01

    Results from calculations of focal spot size for beam transport through a gas-filled reactor are summarized. In the converging beam mode, we find an enlargement of the focal spot due to multiple scattering and zeroth order self-field effects. This enlargement can be minimized by maintaining small reactors together with a careful choice of the gaseous medium. The self-focused mode, on the other hand, is relatively insensitive to the reactor environment, but is critically dependent upon initial beam quality. This requirement on beam quality can be significantly eased by the injection of an electron beam of modest current from the opposite wall

  17. Long-range beam-beam interactions in the Tevatron: Comparing simulation to tune shift data

    International Nuclear Information System (INIS)

    Saritepe, S.; Michelotti, L.; Peggs, S.

    1990-07-01

    Fermilab upgrade plans for the collider operation include a separation scheme in the Tevatron, in which protons and antiprotons are placed on separate helical orbits. The average separation distance between the closed orbits will be 5σ (σ of the proton bunch) except at the interaction regions, B0 and D0, where they collide head-on. The maximum beam-beam total tune shift in the Tevatron is approximately 0.024 (the workable tune space between 5th and 7th order resonances), which was reached in the 1988--1989 collider tun. Helical separation scheme allows us to increase the luminosity by reducing the total beam-beam tune shift. The number of bunches per beam will be 6 in the 1991 collider tun, to be increased to 36 in the following collider runs. To test the viability of this scenario, helical orbit studies are being conducted. The most recent studies concentrated on the injection of 36 proton bunches, procedures related to opening and closing of the helix, the feed-down circuits and the beam-beam interaction. In this paper, we present the results of the beam-beam interaction studies only. Our emphasis is on the tune shift measurements and the comparison to simulation. 4 refs., 9 figs., 2 tabs

  18. An interactive beam position monitor system simulator

    International Nuclear Information System (INIS)

    Ryan, W.A.; Shea, T.J.

    1993-03-01

    A system simulator has been implemented to aid the development of the RHIC position monitor system. Based on the LabVIEW software package by National Instruments, this simulator allows engineers and technicians to interactively explore the parameter space of a system during the design phase. Adjustable parameters are divided into three categories: beam, pickup, and electronics. The simulator uses these parameters in simple formulas to produce results in both time-domain and frequencydomain. During the prototyping phase, these simulated results can be compared to test data acquired with the same software package. The RHIC position monitor system is presented as an example, but the software is applicable to several other systems as well

  19. Transport and interaction of a relativistic electron beam in low pressure neutral gases

    International Nuclear Information System (INIS)

    Iyyengar, S.K.; Rohatgi, V.K.

    1989-01-01

    A numerical study of the transport of a 0.27-MeV, 6.6-kA, 40-ns relativistic electron beam in argon and hydrogen in the pressure range of 0.01--1.0 Torr taking into account charge and current neutralization effects is presented. Ionization by avalanching and by beam and plasma electrons is included in the calculation of plasma density buildup. Plasma heating resulting from return current heating and two-stream instability is taken into account. The computed results of charge transport, net current, and breakdown time are compared with experimental results obtained in this laboratory. The results are in reasonable agreement with the experiment and show a maximum charge transport of 75% at the optimum pressure of 0.1 and 0.6 Torr in argon and hydrogen, respectively. The calculations indicate beam-generated plasma parameters of 10 19 --10 20 m -3 density and 1--5 eV electron temperature

  20. A compact ESQ system for transport and focusing of H- beam from ion source to RFQ

    International Nuclear Information System (INIS)

    Guharay, S.K.; Allen, C.K.; Reiser, M.; Saadatmand, K.; Chang, C.R.

    1992-01-01

    A compact, 6-lens electrostatic quadrupole (ESQ) LEBT (low energy beam transport) system has been constructed at the University of Maryland to transport a 30 mA, 35 kV H - beam over a distance of about 30 cm. A short einzel lens section is included at the end of the ESQ LEBT to establish a good matching of the beam to the radio frequency quadrupole (RFQ) accelerator, and to meet the emittance requirements of the linac in the Super-conducting Super Collider. Computer code predictions on the beam dynamics through the LEBT with experimentally measured input beam data are discussed. (Author) 5 figs., 6 refs

  1. Transport of radioactive ion beams and related safety issues: The {sup 132}Sn{sup +} case study

    Energy Technology Data Exchange (ETDEWEB)

    Osswald, F., E-mail: francis.osswald@iphc.cnrs.fr; Bouquerel, E.; Boutin, D.; Dinkov, A.; Sellam, A. [IPHC/IN2P3/CNRS, University of Strasbourg, 67037 Strasbourg (France); Kazarinov, N. [JINR/FLNR, 141980 Dubna (Russian Federation); Perrot, L. [IPNO/IN2P3/CNRS, University of Paris-Sud-11, 91406 Orsay (France)

    2014-12-15

    The transport of intense radioactive ion beam currents requires a careful design in order to limit the beam losses, the contamination and thus the dose rates. Some investigations based on numerical models and calculations have been performed in the framework of the SPIRAL 2 project to evaluate the performance of a low energy beam transport line located between the isotope separation on line (ISOL) production cell and the experiment areas. The paper presents the results of the transverse phase-space analysis, the beam losses assessment, the resulting contamination, and radioactivity levels. They show that reasonable beam transmission, emittance growth, and dose rates can be achieved considering the current standards.

  2. Simulation of equivalent dose due to accidental electron beam loss in Indus-1 and Indus-2 synchrotron radiation sources using FLUKA code

    International Nuclear Information System (INIS)

    Sahani, P.K.; Dev, Vipin; Singh, Gurnam; Haridas, G.; Thakkar, K.K.; Sarkar, P.K.; Sharma, D.N.

    2008-01-01

    Indus-1 and Indus-2 are two Synchrotron radiation sources at Raja Ramanna Centre for Advanced Technology (RRCAT), India. Stored electron energy in Indus-1 and Indus-2 are 450MeV and 2.5GeV respectively. During operation of storage ring, accidental electron beam loss may occur in addition to normal beam losses. The Bremsstrahlung radiation produced due to the beam losses creates a major radiation hazard in these high energy electron accelerators. FLUKA, the Monte Carlo radiation transport code is used to simulate the accidental beam loss. The simulation was carried out to estimate the equivalent dose likely to be received by a trapped person closer to the storage ring. Depth dose profile in water phantom for 450MeV and 2.5GeV electron beam is generated, from which percentage energy absorbed in 30cm water phantom (analogous to human body) is calculated. The simulation showed the percentage energy deposition in the phantom is about 19% for 450MeV electron and 4.3% for 2.5GeV electron. The dose build up factor in 30cm water phantom for 450MeV and 2.5GeV electron beam are found to be 1.85 and 2.94 respectively. Based on the depth dose profile, dose equivalent index of 0.026Sv and 1.08Sv are likely to be received by the trapped person near the storage ring in Indus-1 and Indus-2 respectively. (author)

  3. Simulation of diode electron source of PSTA latex EBM using OPERA-3D software

    International Nuclear Information System (INIS)

    Taufik; Darsono

    2014-01-01

    Electron beam transport from E-gun to the atmospheres in EBM is determined by main parameters of beam transports such as E-gun, accelerator tube, beam optics (focusing and scanning magnets). In principle the beam transport will optimum if the electron beam travels in axial axes of accelerator tubes, and the beam optics works properly. The EBM E-gun structure of PSTA uses diode type with Pierce cathode where beam transport yield will be affected by electrode voltage of the accelerator tube. To answer above hypothesis the E-gun and accelerator tube will be simulated by making a model used accelerator software programme which is called OPERA-3D. Beam transport parameters, such as distance between cathode and anode of E-gun, accelerator electrode HV, and the symmetry of cathode Pierce E-gun with anode electrode of accelerator tube, will be investigated their impacts to direction and shape of beam transports. The simulation results shows that the three parameters affects to the direction and shape of the beam transport. Diode type of electron gun cannot result parallel electron beam, but the best beam transport of this type electron gun are obtained at the accelerator voltage 300 kV, and the distance between cathode and anode of E-gun 6.1 mm where they are in the symmetry condition. (author)

  4. Tabulated square-shaped source model for linear accelerator electron beam simulation.

    Science.gov (United States)

    Khaledi, Navid; Aghamiri, Mahmood Reza; Aslian, Hossein; Ameri, Ahmad

    2017-01-01

    Using this source model, the Monte Carlo (MC) computation becomes much faster for electron beams. The aim of this study was to present a source model that makes linear accelerator (LINAC) electron beam geometry simulation less complex. In this study, a tabulated square-shaped source with transversal and axial distribution biasing and semi-Gaussian spectrum was investigated. A low energy photon spectrum was added to the semi-Gaussian beam to correct the bremsstrahlung X-ray contamination. After running the MC code multiple times and optimizing all spectrums for four electron energies in three different medical LINACs (Elekta, Siemens, and Varian), the characteristics of a beam passing through a 10 cm × 10 cm applicator were obtained. The percentage depth dose and dose profiles at two different depths were measured and simulated. The maximum difference between simulated and measured percentage of depth doses and dose profiles was 1.8% and 4%, respectively. The low energy electron and photon spectrum and the Gaussian spectrum peak energy and associated full width at half of maximum and transversal distribution weightings were obtained for each electron beam. The proposed method yielded a maximum computation time 702 times faster than a complete head simulation. Our study demonstrates that there was an excellent agreement between the results of our proposed model and measured data; furthermore, an optimum calculation speed was achieved because there was no need to define geometry and materials in the LINAC head.

  5. The beam bunching and transport system of the Argonne positive ion injector

    International Nuclear Information System (INIS)

    Den Hartog, P.K.; Bogaty, J.M.; Bollinger, L.M.; Clifft, B.E.; Pardo, R.C.; Shepard, K.W.

    1989-01-01

    A new positive ion injector (PII) is currently under construction at Argonne that will replace the existing 9-MV tandem electrostatic accelerator as an injector into ATLAS. It consists of an electron-cyclotron resonance-ion source on a 350-kV platform injecting into a superconducting linac optimized for very slow (β ≤ .007 c) ions. This combination can potentially produce even higher quality heavy-ion beams than are currently available from the tandem since the emittance growth within the linac is largely determined by the quality of the bunching and beam transport. The system we have implemented uses a two-stage bunching system, composed of a 4-harmonic gridded buncher located on the ECR high-voltage platform and a room temperature spiral-loaded buncher of novel design. A sinusoidal beam chopper is used for removal of tails. The beam transport is designed to provide mass resolution of M/ΔM > 250 and a doubly-isochronous beamline is used to minimize time spread due to path length differences. 4 refs., 2 figs

  6. The beam bunching and transport system of the Argonne positive ion injector

    Energy Technology Data Exchange (ETDEWEB)

    Den Hartog, P.K.; Bogaty, J.M.; Bollinger, L.M.; Clifft, B.E.; Pardo, R.C.; Shepard, K.W.

    1989-01-01

    A new positive ion injector (PII) is currently under construction at Argonne that will replace the existing 9-MV tandem electrostatic accelerator as an injector into ATLAS. It consists of an electron-cyclotron resonance-ion source on a 350-kV platform injecting into a superconducting linac optimized for very slow (..beta.. less than or equal to .007 c) ions. This combination can potentially produce even higher quality heavy-ion beams than are currently available from the tandem since the emittance growth within the linac is largely determined by the quality of the bunching and beam transport. The system we have implemented uses a two-stage bunching system, composed of a 4-harmonic gridded buncher located on the ECR high-voltage platform and a room temperature spiral-loaded buncher of novel design. A sinusoidal beam chopper is used for removal of tails. The beam transport is designed to provide mass resolution of M/..delta..M > 250 and a doubly-isochronous beamline is used to minimize time spread due to path length differences. 4 refs., 2 figs.

  7. Importance of Resolving the Spectral Support of Beam-plasma Instabilities in Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Shalaby, Mohamad; Broderick, Avery E. [Department of Physics and Astronomy, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1 (Canada); Chang, Philip [Department of Physics, University of Wisconsin-Milwaukee, 1900 E. Kenwood Boulevard, Milwaukee, WI 53211 (United States); Pfrommer, Christoph [Heidelberg Institute for Theoretical Studies, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg (Germany); Lamberts, Astrid [Theoretical Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Puchwein, Ewald, E-mail: mshalaby@live.ca [Institute of Astronomy and Kavli Institute for Cosmology, University of Cambridge, Madingley Road, Cambridge, CB3 0HA (United Kingdom)

    2017-10-20

    Many astrophysical plasmas are prone to beam-plasma instabilities. For relativistic and dilute beams, the spectral support of the beam-plasma instabilities is narrow, i.e., the linearly unstable modes that grow with rates comparable to the maximum growth rate occupy a narrow range of wavenumbers. This places stringent requirements on the box-sizes when simulating the evolution of the instabilities. We identify the implied lower limits on the box size imposed by the longitudinal beam plasma instability, i.e., typically the most stringent condition required to correctly capture the linear evolution of the instabilities in multidimensional simulations. We find that sizes many orders of magnitude larger than the resonant wavelength are typically required. Using one-dimensional particle-in-cell simulations, we show that the failure to sufficiently resolve the spectral support of the longitudinal instability yields slower growth and lower levels of saturation, potentially leading to erroneous physical conclusion.

  8. Importance of Resolving the Spectral Support of Beam-plasma Instabilities in Simulations

    International Nuclear Information System (INIS)

    Shalaby, Mohamad; Broderick, Avery E.; Chang, Philip; Pfrommer, Christoph; Lamberts, Astrid; Puchwein, Ewald

    2017-01-01

    Many astrophysical plasmas are prone to beam-plasma instabilities. For relativistic and dilute beams, the spectral support of the beam-plasma instabilities is narrow, i.e., the linearly unstable modes that grow with rates comparable to the maximum growth rate occupy a narrow range of wavenumbers. This places stringent requirements on the box-sizes when simulating the evolution of the instabilities. We identify the implied lower limits on the box size imposed by the longitudinal beam plasma instability, i.e., typically the most stringent condition required to correctly capture the linear evolution of the instabilities in multidimensional simulations. We find that sizes many orders of magnitude larger than the resonant wavelength are typically required. Using one-dimensional particle-in-cell simulations, we show that the failure to sufficiently resolve the spectral support of the longitudinal instability yields slower growth and lower levels of saturation, potentially leading to erroneous physical conclusion.

  9. Deliverable 6.2 - Software: upgraded MC simulation tools capable of simulating a complete in-beam ET experiment, from the beam to the detected events. Report with the description of one (or few) reference clinical case(s), including the complete patient model and beam characteristics

    CERN Document Server

    The ENVISION Collaboration

    2014-01-01

    Deliverable 6.2 - Software: upgraded MC simulation tools capable of simulating a complete in-beam ET experiment, from the beam to the detected events. Report with the description of one (or few) reference clinical case(s), including the complete patient model and beam characteristics

  10. Low-energy ion beam extraction and transport: Experiment--computer comparison

    International Nuclear Information System (INIS)

    Spaedtke, P.; Brown, I.; Fojas, P.

    1994-01-01

    Ion beam formation at low energy (∼1 keV or so) is more difficult to accomplish than at high energy because of beam blowup by space-charge forces in the uncompensated region within the extractor, an effect which is yet more pronounced for heavy ions and for high beam current density. For the same reasons, the extracted ion beam is more strongly subject to space charge blowup than higher energy beams if it is not space-charge neutralized to a high degree. A version of vacuum arc ion source with an extractor that produces low-energy metal ion beams at relatively high current (∼0.5--10 kV at up to ∼100 mA) using a multi-aperture, accel--decel extractor configuration has been created. The experimentally observed beam extraction characteristics of this source is compared with those predicted using the AXCEL-INP code, and the implied downstream beam transport with theoretical expectations. It is concluded that the low-energy extractor performance is in reasonable agreement with the code, and that good downstream space charge neutralization is obtained. Here, the code and the experimental results are described, and the features that contribute to good low-energy performance are discussed

  11. Impurity transport during neutral beam injection in the ISX-B tokamak

    International Nuclear Information System (INIS)

    Isler, R.C.; Crume, E.C.; Arnurius, D.E.; Murray, L.E.

    1980-10-01

    In ohmically heated ISX-B discharges, both the intrinsic iron impurity ions and small amounts of argon introduced as a test gas accumulate at the center of the plasma. But during certain beam-heated discharges, it appears that this accumulation does not take place. These results may reflect the conclusion of Stacey and Sigmar that momentum transferred from the beams to the plasma can inhibit inward impurity transport

  12. Standardization of transportation classes for object-oriented deployment simulations.

    Energy Technology Data Exchange (ETDEWEB)

    Burke, J. F., Jr.; Howard, D. L.; Jackson, J.; Macal, C. M.; Nevins, M. R.; Van Groningen, C. N.

    1999-07-30

    Many recent efforts to integrate transportation and deployment simulations, although beneficial, have lacked a feature vital for seamless integration: a common data class representation. It is an objective of the Department of Defense (DoD) to standardize all classes used in object-oriented deployment simulations by developing a standard class attribute representation and behavior for all deployment simulations that rely on an underlying class representation. The Extensive Hierarchy and Object Representation for Transportation Simulations (EXHORT) is a collection of three hierarchies that together will constitute a standard and consistent class attribute representation and behavior that could be used directly by a large set of deployment simulations. The first hierarchy is the Transportation Class Hierarchy (TCH), which describes a significant portion of the defense transportation system; the other two deal with infrastructure and resource classes. EXHORT will allow deployment simulations to use the same set of underlying class data, ensure transparent exchanges, reduce the effort needed to integrate simulations, and permit a detailed analysis of the defense transportation system. This paper describes EXHORT's first hierarchy, the TCH, and provides a rationale for why it is a helpful tool for modeling major portions of the defense transportation system.

  13. Fan-beam intensity modulated proton therapy.

    Science.gov (United States)

    Hill, Patrick; Westerly, David; Mackie, Thomas

    2013-11-01

    This paper presents a concept for a proton therapy system capable of delivering intensity modulated proton therapy using a fan beam of protons. This system would allow present and future gantry-based facilities to deliver state-of-the-art proton therapy with the greater normal tissue sparing made possible by intensity modulation techniques. A method for producing a divergent fan beam of protons using a pair of electromagnetic quadrupoles is described and particle transport through the quadrupole doublet is simulated using a commercially available software package. To manipulate the fan beam of protons, a modulation device is developed. This modulator inserts or retracts acrylic leaves of varying thickness from subsections of the fan beam. Each subsection, or beam channel, creates what effectively becomes a beam spot within the fan area. Each channel is able to provide 0-255 mm of range shift for its associated beam spot, or stop the beam and act as an intensity modulator. Results of particle transport simulations through the quadrupole system are incorporated into the MCNPX Monte Carlo transport code along with a model of the range and intensity modulation device. Several design parameters were investigated and optimized, culminating in the ability to create topotherapy treatment plans using distal-edge tracking on both phantom and patient datasets. Beam transport calculations show that a pair of electromagnetic quadrupoles can be used to create a divergent fan beam of 200 MeV protons over a distance of 2.1 m. The quadrupole lengths were 30 and 48 cm, respectively, with transverse field gradients less than 20 T/m, which is within the range of water-cooled magnets for the quadrupole radii used. MCNPX simulations of topotherapy treatment plans suggest that, when using the distal edge tracking delivery method, many delivery angles are more important than insisting on narrow beam channel widths in order to obtain conformal target coverage. Overall, the sharp distal

  14. Comparison of beam deposition for three neutral beam injection codes

    International Nuclear Information System (INIS)

    Wieland, R.M.; Houlberg, W.A.; Mense, A.T.

    1979-03-01

    The three neutral beam injection codes BEAM (Houlberg, ORNL), HOFR (Howe, ORNL), and FREYA (Post, PPPL) are compared with respect to the calculation of the fast ion deposition profile H(r). Only plasmas of circular cross section are considered, with injection confined to the mid-plane of the torus. The approximations inherent in each code are pointed out, and a series of comparisons varying several parameters (beam energy and radius, machine size, and injection angle) shows excellent agreement among all the codes. A cost comparison (execution time and memory requirements) is made which points out the relative merits of each code within the context of incorporation into a plasma transport simulation code

  15. Fast-ion transport and neutral beam current drive in ASDEX upgrade

    DEFF Research Database (Denmark)

    Geiger, B.; Weiland, M.; Jacobsen, Asger Schou

    2015-01-01

    The neutral beam current drive efficiency has been investigated in the ASDEX Upgrade tokamak by replacing on-axis neutral beams with tangential off-axis beams. A clear modification of the radial fast-ion profiles is observed with a fast-ion D-alpha diagnostic that measures centrally peaked profiles...... during on-axis injection and outwards shifted profiles during off-axis injection. Due to this change of the fast-ion population, a clear modification of the plasma current profile is predicted but not observed by a motional Stark effect diagnostic. The fast-ion transport caused by MHD activity has been...

  16. The solenoidal transport option: IFE drivers, near term research facilities, and beam dynamics

    International Nuclear Information System (INIS)

    Lee, E.P.; Briggs, R.J.

    1997-09-01

    Solenoidal magnets have been used as the beam transport system in all the high current electron induction accelerators that have been built in the past several decades. They have also been considered for the front end transport system for heavy ion accelerators for Inertial Fusion Energy (IFE) drivers, but this option has received very little attention in recent years. The analysis reported here was stimulated mainly by the recent effort to define an affordable open-quotes Integrated Research Experimentclose quotes (IRE) that can meet the near term needs of the IFE program. The 1996 FESAC IFE review panel agreed that an integrated experiment is needed to fully resolve IFE heavy ion driver science and technology issues; specifically, open-quotes the basic beam dynamics issues in the accelerator, the final focusing and transport issues in a reactor-relevant beam parameter regime, and the target heating phenomenologyclose quotes. The development of concepts that can meet these technical objectives and still stay within the severe cost constraints all new fusion proposals will encounter is a formidable challenge. Solenoidal transport has a very favorable scaling as the particle mass is decreased (the main reason why it is preferred for electrons in the region below 50 MeV). This was recognized in a recent conceptual study of high intensity induction linac-based proton accelerators for Accelerator Driven Transmutation Technologies, where solenoidal transport was chosen for the front end. Reducing the ion mass is an obvious scaling to exploit in an IRE design, since the output beam voltage will necessarily be much lower than that of a full scale driver, so solenoids should certainly be considered as one option for this experiment as well

  17. Design features and operational characteristics of the PEP beam-transport and injection system

    International Nuclear Information System (INIS)

    Peterson, J.M.; Brown, K.L.; Truher, J.B.

    1981-03-01

    The PEP beam-transport system was designed to transmit 4-to-15 GeV electron and positron beams from the SLAC linac within a +- 0.8% momentum band, to have flexible tuning of the betatron and off-momentum functions for matching into the PEP storage ring, and to have convenient operating characteristics. The transport lines were brought into operation quickly and have operated well. Electron injection has been consistent and efficient and relatively easy to accomplish. Positron injection also has been satisfactory but is variable and more sensitive to ring conditions

  18. Optimization of laser accelerated proton beams for possible applications

    Energy Technology Data Exchange (ETDEWEB)

    Al-Omari, Husam [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Planckstrasse 1, 64291 Darmstadt (Germany); Collaboration: LIGHT-Collaboration

    2013-07-01

    Optimization of transported proton beams through a pulsed solenoid in the laser proton experiment LIGHT at GSI has been studied numerically. TraceWin, SRIM and ATIMA codes were employed for this study with an initial distribution generated by MATLAB program fitted to Phelix measured data. Two individual tools have been used to produce protons beam as a later beam source: an aperture located at the solenoid focal spot as energy selection tool; and a scattering foil at a suitable position in the beam path that smoothens the simulated radial energy imprint on the beam profile. The simulation results show that the proton energy spectrum is filtered by the aperture and the radial energy correlation is smoothened.

  19. Space-charge limits on the transport of ion beams in a long alternating gradient system

    International Nuclear Information System (INIS)

    Tiefenback, M.G.

    1986-11-01

    We have experimentally studied the space-charge-dominated transport of ion beams in an alternating-gradient channel, without acceleration. We parameterize the focusing strength in terms of the zero-current ''betatron'' oscillation phase advance rate, σ 0 (degrees per focusing period). We have investigated the conditions for ''stability'', defined as the constancy of the total current and phase space area of the beam during transport. We find that the beam may be transported with neither loss of current nor growth in phase area if σ 0 0 . In this regime, the space-charge repulsive force can counter 98-99% of the externally applied focusing field, and the oscillation frequency of the beam particles can be depressed by self-forces to almost a factor of 10 below the zero-current value, limited only by the optical quality of our ion source. For σ 0 > 90 0 , we find that collective interactions bound the maintainable density of the beam, and we present a simple, semi-empirical characterization for stability, within our ability to distinguish the growth rate from zero in our apparatus. Our channel comprises 87 quadrupole lenses, 5 of which are used to prepare the beam for injection into the non-azimuthally-symmetric focusing channel

  20. Simulation of ultrasonic surface waves with multi-Gaussian and point source beam models

    International Nuclear Information System (INIS)

    Zhao, Xinyu; Schmerr, Lester W. Jr.; Li, Xiongbing; Sedov, Alexander

    2014-01-01

    In the past decade, multi-Gaussian beam models have been developed to solve many complicated bulk wave propagation problems. However, to date those models have not been extended to simulate the generation of Rayleigh waves. Here we will combine Gaussian beams with an explicit high frequency expression for the Rayleigh wave Green function to produce a three-dimensional multi-Gaussian beam model for the fields radiated from an angle beam transducer mounted on a solid wedge. Simulation results obtained with this model are compared to those of a point source model. It is shown that the multi-Gaussian surface wave beam model agrees well with the point source model while being computationally much more efficient

  1. High-gradient two-beam electron accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Hirshfield, Jay L. [Omega-P, Inc., New Haven, CT (United States)

    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.

  2. Automated analysis for detecting beams in laser wakefield simulations

    International Nuclear Information System (INIS)

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

    2008-01-01

    Laser wakefield particle accelerators have shown the potential to generate electric fields thousands of times higher than those of conventional accelerators. The resulting extremely short particle acceleration distance could yield a potential new compact source of energetic electrons and radiation, with wide applications from medicine to physics. Physicists investigate laser-plasma internal dynamics by running particle-in-cell simulations; however, this generates a large dataset that requires time-consuming, manual inspection by experts in order to detect key features such as beam formation. This paper describes a framework to automate the data analysis and classification of simulation data. First, we propose a new method to identify locations with high density of particles in the space-time domain, based on maximum extremum point detection on the particle distribution. We analyze high density electron regions using a lifetime diagram by organizing and pruning the maximum extrema as nodes in a minimum spanning tree. Second, we partition the multivariate data using fuzzy clustering to detect time steps in a experiment that may contain a high quality electron beam. Finally, we combine results from fuzzy clustering and bunch lifetime analysis to estimate spatially confined beams. We demonstrate our algorithms successfully on four different simulation datasets

  3. Beam transport

    International Nuclear Information System (INIS)

    1988-01-01

    The beam diagnostic components for both the transfer and the high-energy beamlines perform well except for some of the scanners whose noise pick-up has become a problem, especially at low beam intensities. This noise pick-up is primarily due to deterioration of the bearings in the scanner. At some locations in the high-energy beamlines, scanners were replaced by harps as the scanners proved to be practically useless for the low-intensity beams required in the experimental areas. The slits in the low-energy beamline, which are not water-cooled, have to be repaired at regular intervals because of vacuum leaks. Overheating causes the ceramic feedthroughs to deteriorate resulting in the vacuum leaks. Water-cooled slits have been ordered to replace the existing slits which will later be used in the beamlines associated with the second injector cyclotron SPC2. The current-measurement system will be slightly modified and should then be much more reliable. 3 figs

  4. Beam Loss Patterns at the LHC Collimators Measurements & Simulations

    CERN Document Server

    Böhlen, Till Tobias

    2008-01-01

    The Beam Loss Monitoring (BLM) system of the Large Hadron Collider (LHC) detects particle losses of circulating beams and initiates an emergency extraction of the beam in case that the BLM thresholds are exceeded. This protection is required as energy deposition in the accelerator equipment due to secondary shower particles can reach critical levels; causing damage to the beam-line components and quenches of superconducting magnets. Robust and movable beam line elements, so-called collimators, are the aperture limitations of the LHC. Consequently, they are exposed to the excess of lost beam particles and their showers. Proton loss patterns at LHC collimators have to be determined to interpret the signal of the BLM detectors and to set adequate BLM thresholds for the protection of collimators and other equipment in case of unacceptably increased loss rates. The first part of this work investigates the agreement of BLM detector measurements with simulations for an LHC-like collimation setup. The setup consists ...

  5. Linac4 Low Energy Beam Measurements with Negative Hydrogen

    CERN Document Server

    Scrivens, R; Crettiez, O; Dimov, V; Gerard, D; Granemann Souza, E; Guida, R; Hansen, J; Lallement, J B; Lettry, J; Lombardi, A; Midttun, O; Pasquino, C; Raich, U; Riffaud, B; Roncarolo, F; Valerio-Lizarraga, C A; Wallner, J; Yarmohammadi Satri, M; Zickler, T

    2014-01-01

    Linac4, a 160 MeV normal-conducting H- linear accelerator, is the first step in the upgrade of the beam intensity available from the LHC proton injectors at CERN. The Linac4 Low Energy Beam Transport (LEBT) line from the pulsed 2 MHz RF driven ion source, to the 352 MHz RFQ has been built and installed at a test stand, and has been used to transport and match to the RFQ a pulsed 14 mA H- beam at 45 keV. A temporary slit-and-grid emittance measurement system has been put in place to characterize the beam delivered to the RFQ. In this paper a description of the LEBT and its beam diagnostics is given, and the results of beam emittance measurements and beam transmission measurements through the RFQ are compared with the expectation from simulations.

  6. SUPERCONDUCTING QUADRUPOLE ARRAYS FOR MULTIPLE BEAM TRANSPORT

    International Nuclear Information System (INIS)

    Rainer Meinke Carl Goodzeit Penny Ball Roger Bangerter

    2003-01-01

    The goal of this research was to develop concepts for affordable, fully functional arrays of superconducting quadrupoles for multi-beam transport and focusing in heavy ion fusion (HIF)accelerators. Previous studies by the Virtual National Laboratory (VNL) collaboration have shown that the multi-beam transport system (consisting of alternating gradient quadrupole magnets, a beam vacuum system, and the beam monitor and control system) will likely be one of the most expensive and critical parts of such an accelerator. This statement is true for near-term fusion research accelerators as well as accelerators for the ultimate goal of power production via inertial fusion. For this reason, research on superconducting quadrupole arrays is both timely and important for the inertial fusion energy (IFE) research program. This research will also benefit near-term heavy ion fusion facilities such as the Integrated Research Experiment (IRE)and/or the Integrated Beam Experiment (IBX). We considered a 2-prong approach that addresses the needs of both the nearer and longer term requirements of the inertial fusion program. First, we studied the flat coil quadrupole design that was developed by LLNL; this magnet is 150 mm long with a 50 mm aperture and thus is suitable for near term experiments that require magnets of a small length to aperture ratio. Secondly, we studied the novel double-helix quadrupole (DHQ) design in a small (3 x 3) array configuration; this design can provide an important step to the longer term solution of loW--cost, easy to manufacture array constructions. Our Phase I studies were performed using the AMPERES magnetostatic analysis software. Consideration of these results led to plans for future magnet RandD construction projects. The first objective of Phase I was to develop the concept of a superconducting focusing array that meets the specific requirements of a heavy ion fusion accelerator. Detailed parameter studies for such quadrupole arrays were performed

  7. SUPERCONDUCTING QUADRUPOLE ARRAYS FOR MULTIPLE BEAM TRANSPORT

    Energy Technology Data Exchange (ETDEWEB)

    Rainer Meinke

    2003-10-01

    The goal of this research was to develop concepts for affordable, fully functional arrays of superconducting quadrupoles for multi-beam transport and focusing in heavy ion fusion (HIF)accelerators. Previous studies by the Virtual National Laboratory (VNL) collaboration have shown that the multi-beam transport system (consisting of alternating gradient quadrupole magnets, a beam vacuum system, and the beam monitor and control system) will likely be one of the most expensive and critical parts of such an accelerator. This statement is true for near-term fusion research accelerators as well as accelerators for the ultimate goal of power production via inertial fusion. For this reason, research on superconducting quadrupole arrays is both timely and important for the inertial fusion energy (IFE) research program. This research will also benefit near-term heavy ion fusion facilities such as the Integrated Research Experiment (IRE)and/or the Integrated Beam Experiment (IBX). We considered a 2-prong approach that addresses the needs of both the nearer and longer term requirements of the inertial fusion program. First, we studied the flat coil quadrupole design that was developed by LLNL; this magnet is 150 mm long with a 50 mm aperture and thus is suitable for near term experiments that require magnets of a small length to aperture ratio. Secondly, we studied the novel double-helix quadrupole (DHQ) design in a small (3 x 3) array configuration; this design can provide an important step to the longer term solution of low-cost, easy to manufacture array constructions. Our Phase I studies were performed using the AMPERES magnetostatic analysis software. Consideration of these results led to plans for future magnet R&D construction projects. The first objective of Phase I was to develop the concept of a superconducting focusing array that meets the specific requirements of a heavy ion fusion accelerator. Detailed parameter studies for such quadrupole arrays were performed

  8. MUSTAFA a tool for numerical simulations of the beam behavior in a linac

    CERN Document Server

    Guignard, Gilbert

    1998-01-01

    MUSTAFA stands for MUltibunch Simulation and Tracking Algorithm for Future linear Accelerators and provides an environment for tracking a multibunch beam accelerated in the linac of a collider. It is made of three parts: i) an interactive utility MBUNCH which allows to run the simulations, edit the input data, systematically vary some parameters, launch statistics on misalignment realisations and select the outputs, ii) the tracking program itself MBTR that includes magnetic focusing, acceleration, wakefields, misalignments and trajectory correction, and iii) a graphcs facility called MOVIE th at provides an animated representation of the transverse motion within each bunch of a train, either in the geometric space or in the phase space. While MBTR is written in FORTRAN, the other two codes are written in QUICKBASIC (MS V4.5). They run on PC Pentium computers in a stand-alone mode, independent of any network. Hence MUSTAFA is easily transportable and offers a unique graphics facility. It has been extensively ...

  9. Computer simulation of radial transport in tandem mirror machines

    International Nuclear Information System (INIS)

    Gilmore, J.M.

    1979-01-01

    A code used for simulation of classical radial transport in the 2XIIB experiment has been modified to simulate radial transport in TMX. Results have been obtained using classical transport coefficients and also using very simple trial neoclassical resonant transport coefficients. Comparison of the results obtained with solely classical transport and with both classical and neo-classical transport indicate that neoclassical transport depresses the ion density by approximately 5%. The central cell ion temperature is increased by approximately by the neo-classical transport, as is the electron temperature

  10. Impurity Dynamics under Neutral Beam Injection at TJ-II (simulation)

    International Nuclear Information System (INIS)

    Guasp, J.; Fuentes, C.; Liniers, M.

    2001-01-01

    In this study the simulations of plasma transport under NBI for TJ-II, previously performed, are extended. Since than a considerable number of important modifications have been introduced in the model: change of magnetic configuration, use of experimental initial profiles, expansion of the Data base from NBI calculations and, mainly, a detailed handling of impurities with inclusion of sputtering effects. Moreover there is now a particular emphasis on the analysis of the conditions for discharge collapse and on the possible effects of single beam injection. This analysis of impurity behaviour with sputtering shows that in the expected usual cases there is no radioactive collapse and that if the recycling coefficients remain lower the unity it is always possible to find a strategy for external gas puffing leading to a stationary state, with densities below the limit and efficient NBI absorption (>50%). The radioactive collapse can appear either at high densities (central value higher than 1.4x10''20 m''3), excessive influx of impurities (i. e. with sputtering rates higher than twice the expected values) o for insufficient injected beam power (less than 45 kW). The present study analyses only the 100 4 4 6 4 configuration of TJ-II, but future works will start a systematic scan of configuration using this same model. (Author) 12 Refs

  11. Numerical simulation for the accelerator of the KSTAR neutral beam ion source

    International Nuclear Information System (INIS)

    Kim, Tae-Seong; Jeong, Seung Ho; In, Sang Ryul

    2010-01-01

    Recent experiments with a prototype long-pulse, high-current ion source being developed for the neutral beam injection system of the Korea Superconducting Tokamak Advanced Research have shown that the accelerator grid assembly needs a further upgrade to achieve the final goal of 120keV/65A for the deuterium ion beam. The accelerator upgrade concept was determined theoretically by simulations using the IGUN code. The simulation study was focused on finding parameter sets that raise the optimum perveance as large as possible and reduce the beam divergence as low as possible. From the simulation results, it was concluded that it is possible to achieve this goal by sliming the plasma grid (G1), shortening the second gap (G2-G3), and adjusting the G2 voltage ratio.

  12. The NOvA simulation chain

    International Nuclear Information System (INIS)

    Aurisano, A; Sousa, A; Backhouse, C; Patterson, R; Hatcher, R; Mayer, N; Musser, J; Schroeter, R

    2015-01-01

    The NOνA experiment is a two-detector, long-baseline neutrino experiment operating in the recently upgraded NuMI muon neutrino beam. Simulating neutrino interactions and backgrounds requires many steps including: the simulation of the neutrino beam flux using FLUKA and the FLUGG interface; cosmic ray generation using CRY; neutrino interaction modeling using GENIE; and a simulation of the energy deposited in the detector using GEANT4. To shorten generation time, the modeling of detector-specific aspects, such as photon transport, detector and electronics noise, and readout electronics, employs custom, parameterized simulation applications. We will describe the NOνA simulation chain, and present details on the techniques used in modeling photon transport near the ends of cells, and in developing a novel data-driven noise simulation. Due to the high intensity of the NuMI beam, the Near Detector samples a high rate of muons originating in the surrounding rock. In addition, due to its location on the surface at Ash River, MN, the Far Detector collects a large rate ( ∼ 140 kHz) of cosmic muons. We will discuss the methods used in NOνA for overlaying rock muons and cosmic ray muons with simulated neutrino interactions and show how realistically the final simulation reproduces the preliminary NOνA data. (paper)

  13. The NOvA simulation chain

    Science.gov (United States)

    Aurisano, A.; Backhouse, C.; Hatcher, R.; Mayer, N.; Musser, J.; Patterson, R.; Schroeter, R.; Sousa, A.

    2015-12-01

    The NOνA experiment is a two-detector, long-baseline neutrino experiment operating in the recently upgraded NuMI muon neutrino beam. Simulating neutrino interactions and backgrounds requires many steps including: the simulation of the neutrino beam flux using FLUKA and the FLUGG interface; cosmic ray generation using CRY; neutrino interaction modeling using GENIE; and a simulation of the energy deposited in the detector using GEANT4. To shorten generation time, the modeling of detector-specific aspects, such as photon transport, detector and electronics noise, and readout electronics, employs custom, parameterized simulation applications. We will describe the NOνA simulation chain, and present details on the techniques used in modeling photon transport near the ends of cells, and in developing a novel data-driven noise simulation. Due to the high intensity of the NuMI beam, the Near Detector samples a high rate of muons originating in the surrounding rock. In addition, due to its location on the surface at Ash River, MN, the Far Detector collects a large rate (˜ 140 kHz) of cosmic muons. We will discuss the methods used in NOνA for overlaying rock muons and cosmic ray muons with simulated neutrino interactions and show how realistically the final simulation reproduces the preliminary NOνA data.

  14. Research of transportation efficiency of low-energy high- current electron beam in plasma channel in external magnetic field

    International Nuclear Information System (INIS)

    Vagin, E S; Grigoriev, V P

    2015-01-01

    Effective high current (5-20 kA) and low energy (tens of keV) electrons beam transportation is possible only with almost complete charging neutralization. It is also necessary to use quite high current neutralization for elimination beam self-pinching effect. The research is based on the self-consistent mathematical model that takes into account beam and plasma particles dynamic, current and charge neutralization of electron beam and examines the transportation of electron beam into a chamber with low-pressure plasma in magnetic field. A numerical study was conducted using particle in cell (PIC) method. The study was performed with various system parameters: rise time and magnitude of the beam current, gas pressure and plasma density and geometry of the system. Regularities of local virtual cathode field generated by the beam in the plasma channel, as well as ranges of parameters that let transportation beam with minimal losses, depending on the external magnetic field were determined through a series of numerical studies. In addition, the assessment of the impact of the plasma ion mobility during the transition period and during steady beam was performed. (paper)

  15. High quality electron beams from a laser wakefield accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Wiggins, S M; Issac, R C; Welsh, G H; Brunetti, E; Shanks, R P; Anania, M P; Cipiccia, S; Manahan, G G; Aniculaesei, C; Ersfeld, B; Islam, M R; Burgess, R T L; Vieux, G; Jaroszynski, D A [SUPA, Department of Physics, University of Strathclyde, Glasgow (United Kingdom); Gillespie, W A [SUPA, Division of Electronic Engineering and Physics, University of Dundee, Dundee (United Kingdom); MacLeod, A M [School of Computing and Creative Technologies, University of Abertay Dundee, Dundee (United Kingdom); Van der Geer, S B; De Loos, M J, E-mail: m.wiggins@phys.strath.ac.u [Pulsar Physics, Burghstraat 47, 5614 BC Eindhoven (Netherlands)

    2010-12-15

    High quality electron beams have been produced in a laser-plasma accelerator driven by femtosecond laser pulses with a peak power of 26 TW. Electrons are produced with an energy up to 150 MeV from the 2 mm gas jet accelerator and the measured rms relative energy spread is less than 1%. Shot-to-shot stability in the central energy is 3%. Pepper-pot measurements have shown that the normalized transverse emittance is {approx}1{pi} mm mrad while the beam charge is in the range 2-10 pC. The generation of high quality electron beams is understood from simulations accounting for beam loading of the wakefield accelerating structure. Experiments and self-consistent simulations indicate that the beam peak current is several kiloamperes. Efficient transportation of the beam through an undulator is simulated and progress is being made towards the realization of a compact, high peak brilliance free-electron laser operating in the vacuum ultraviolet and soft x-ray wavelength ranges.

  16. Simulation studies of the LAMPF proton linac

    International Nuclear Information System (INIS)

    Garnett, R.W.; Gray, E.R.; Rybarcyk, L.J.; Wangler, T.P.

    1995-01-01

    The LAMPF accelerator consists of two 0.75-MeV injectors, one for H + and the other for H - , a separate low-energy beam transport (LEBT) line for each beam species, a 0.75 to 100-MeV drift-tube linac (DTL) operating at 201.25-MHz, a 100-MeV transition region (TR), and a 100 to 800-MeV side-coupled linac (SCL) operating at 805-MHz. Each LEBT line consists of a series of quadrupoles to transport and transversely match the beam. The LEBT also contains a prebuncher, a main buncher, and an electrostatic deflector. The deflector is used to limit the fraction of a macropulse which is seen by the beam diagnostics throughout the linac. The DTL consists of four rf tanks and uses singlet FODO transverse focusing. The focusing period is doubled in the last two tanks by placing a quadrupole only in every other drift-tube. Doublet FDO transverse focusing is used in the SCL. The TR consists of separate transport lines for the H + and H - beams. The pathlengths for the two beams differ, by introducing bends, so as to delay arrival of one beam relative to the other and thereby produce the desired macropulse time structure. Peak beam currents typically range from 12 to 18-mA for varying macropulse lengths which give an average beam current of 1-mA. The number of particles per bunch is of the order 10 8 . The work presented here is an extension of previous work. The authors have attempted to do a more complete simulation by including modeling of the LEBT. No measurements of the longitudinal structure of the beam, except phase-scans, are performed at LAMPF. The authors show that, based on simulation results, the primary causes of beam spill are inefficient longitudinal capture and the lack of longitudinal matching. Measurements to support these claims are not presently made at LAMPF. However, agreement between measurement and simulation for the transverse beam properties and transmissions serve to benchmark the simulations

  17. Beam simulations with initial bunch noise in superconducting RF proton linacs

    CERN Document Server

    Tückmantel, J

    2010-01-01

    Circular machines are plagued by coupled bunch instabilities (CBI), driven by impedance peaks, where then all cavity higher order modes (HOMs) are possible drivers. Limiting the CBI growth rate is the fundamental reason that all superconducting rf cavities in circular machines are equipped with HOM dampers. The question arises if for similar reasons HOM damping would not be imperative also in high current superconducting rf proton linacs. Therefore we have simulated the longitudinal bunched beam dynamics in such machines, also including charge and position noise on the injected bunches. Simulations were executed for a generic linac with properties close to the planned SPL at CERN, SNS, or Project X at FNAL. It was found that with strong bunch noise and monopole HOMs with high Qext large beam scatter, possibly exceeding the admittance of a receiving machine, cannot be excluded. A transverse simulation shows similar requirements. Therefore including initial bunch noise in any beam dynamic study on superconducti...

  18. Beam Delivery Simulation - Recent Developments and Optimization

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00232566; Boogert, Stewart Takashi; Garcia-Morales, H; Gibson, Stephen; Kwee-Hinzmann, Regina; Nevay, Laurence James; Deacon, Lawrence Charles

    2015-01-01

    Beam Delivery Simulation (BDSIM) is a particle tracking code that simulates the passage of particles through both the magnetic accelerator lattice as well as their interaction with the material of the accelerator itself. The Geant4 toolkit is used to give a full range of physics processes needed to simulate both the interaction of primary particles and the production and subsequent propagation of secondaries. BDSIM has already been used to simulate linear accelerators such as the International Linear Collider (ILC) and the Compact Linear Collider (CLIC), but it has recently been adapted to simulate circular accelerators as well, producing loss maps for the Large Hadron Collider (LHC). In this paper the most recent developments, which extend BDSIM’s functionality as well as improve its efficiency are presented. Improvement and refactorisation of the tracking algorithms are presented alongside improved automatic geometry construction for increased particle tracking speed.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    R. Bruce

    2014-08-01

    Full Text Available 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.

  1. Beam Tools for Geant4 (User's Guide)

    International Nuclear Information System (INIS)

    V.Daniel Elvira, Paul Lebrun and Panagiotis Spentzouris email daniel@fnal.gov

    2002-01-01

    Geant4 is a tool kit developed by a collaboration of physicists and computer professionals in the high energy physics field for simulation of the passage of particles through matter. The motivation for the development of the Beam Tools is to extend the Geant4 applications to accelerator physics. The Beam Tools are a set of C++ classes designed to facilitate the simulation of accelerator elements: r.f. cavities, magnets, absorbers, etc. These elements are constructed from Geant4 solid volumes like boxes, tubes, trapezoids, or spheers. There are many computer programs for beam physics simulations, but Geant4 is ideal to model a beam through a material or to integrate a beam line with a complex detector. There are many such examples in the current international High Energy Physics programs. For instance, an essential part of the RandD associated with the Neutrino Source/Muon Collider accelerator is the ionization cooling channel, which is a section of the system aimed to reduce the size of the muon beam in phase space. The ionization cooling technique uses a combination of linacs and light absorbers to reduce the transverse momentum and size of the beam, while keeping the longitudinal momentum constant. The MuCool/MICE (muon cooling) experiments need accurate simulations of the beam transport through the cooling channel in addition to a detailed simulation of the detectors designed to measure the size of the beam. The accuracy of the models for physics processes associated with muon ionization and multiple scattering is critical in this type of applications. Another example is the simulation of the interaction region in future accelerators. The high luminosity and background environments expected in the Next Linear Collider (NLC) and the Very Large Hadron Collider (VLHC) pose great demand on the detectors, which may be optimized by means of a simulation of the detector-accelerator interface

  2. Guiding center simulations of strong ion beams with applications to the Counterstreaming Ion Torus

    International Nuclear Information System (INIS)

    Tull, C.

    1978-03-01

    In the proposed Counterstreaming Ion Torus (CIT) steady state rather than pulsed operation may be possible if all of the plasma power density is provided by neutral beam injection. After the neutral beams have penetrated the magnetic field, strong ion beam currents are produced. A major concern with the relatively strong counterstreaming ion currents is the effect of the beam self-magnetic fields on the macroscopic equilibrium of the system. Pinching and self focusing of the individual beams may occur, or the repulsive interaction of the two oppositely directed beam currents may destroy the equilibrium entirely. We investigate this macroscopic behavior of the ion beams with a guiding center plasma particle simulation model and we describe a model we have developed to simulate steady state behavior in an ideal CIT configuration

  3. Neoclassical transport of energetic beam ions in the Large Helical Device

    International Nuclear Information System (INIS)

    Murakami, Sadayoshi; Yamada, Hiroshi; Kaneko, Osamu

    2000-01-01

    The neoclassical (collisional) transport of energetic ions is investigated by the global neoclassical transport simulation in the Large Helical Device (LHD). The steady state distributions of energetic ions are evaluated assuming an energetic particle source by NBI heating (tangentally injected). Significant radial transport of energetic ions can be seen due to the radial motion of trapped particles in the velocity region below near critical velocity. Our simulation results show relatively good agreements with the experimental results of fast particle measurements in the LHD. This suggests an important role of neoclassical transport in the radial transport process of energetic ions in heliotrons. (author)

  4. Beam dynamics simulation of the S-DALINAC injector section

    Energy Technology Data Exchange (ETDEWEB)

    Franke, Sylvain; Ackermann, Wolfgang; Weiland, Thomas [Institut fuer Theorie Elektromagnetischer Felder, Technische Universitaet Darmstadt, Darmstadt (Germany)

    2013-07-01

    In order to extend the experimental possibilities at the superconducting electron linear accelerator S-DALINAC a new polarized gun has recently been installed in addition to the well-established thermionic electron source. Beside the two electron sources the injector section consists of several short quadrupole triplets, an alpha magnet, a Wien filter and a chopper/prebuncher system. The setup of these components differs depending on whether bunched polarized electrons with kinetic energy in the 100 keV range are supplied by the polarized source or whether a continuous unpolarized 250 keV electron beam is extracted from the thermionic gun. The electrons pass through the injector at a relatively low energy and therefore are very sensitive to the beam forming elements in this section. Thus, a proper knowledge of the particle distribution at the exit of the injector section is essential for the quality of any simulation of the subsequent accelerator parts. In this contribution first numerical beam dynamics simulation results of the S-DALINAC injector setup are discussed.

  5. Electron and ion heat transport with lower hybrid current drive and neutral beam injection heating in ASDEX

    International Nuclear Information System (INIS)

    Soeldner, F.X.; Pereverzev, G.V.; Bartiromo, R.; Fahrbach, H.U.; Leuterer, F.; Murmann, H.D.; Staebler, A.; Steuer, K.H.

    1993-01-01

    Transport code calculations were made for experiments with the combined operation of lower hybrid current drive and heating and of neutral beam injection heating on ASDEX. Peaking or flattening of the electron temperature profile are mainly explained by modifications of the MHD induced electron heat transport. They originate from current profile changes due to lower hybrid and neutral beam current drive and to contributions from the bootstrap current. Ion heat transport cannot be described by one single model for all heating scenarios. The ion heat conductivity is reduced during lower hybrid heated phases with respect to Ohmic and neutral beam heating. (author). 13 refs, 5 figs

  6. Performance of a shallow-focus applied-magnetic-field diode for ion-beam-transport experiments

    Energy Technology Data Exchange (ETDEWEB)

    Young, F.C.; Neri, J.M.; Ottinger, P.F. [Naval Research Lab., Washington, DC (United States); Rose, D.V. [JAYCOR, Vienna (Vatican City State, Holy See); Jones, T.G.; Oliver, B.V.

    1997-12-31

    An applied-magnetic-field ion diode to study the transport of intense ion beams for light-ion inertial confinement fusion is being operated on the Gamble II generator at NRL. A Large-area (145-cm{sup 2}), shallow-focusing diode is used to provide the ion beam required for self-pinched transport (SPT) experiments. Experiments have demonstrated focusing at 70 cm for 1.2-MV, 40-kA protons. Beyond the focus, the beam hollows out consistent with 20--30 mrad microdivergence. The effect of the counter-pulse B-field on altering the ion-beam trajectories and improving the focus has been diagnosed with a multiple-pinhole-camera using radiachromic film. This diagnostic is also used to determine the radial and azimuthal uniformity of ion emission at the anode for different B-field conditions. Increasing the diode voltage to 1.5 MV and optimizing the ion current are planned before initiating SPT experiments. Experiments to measure the spatial beam profile at focus, i.e., the SPT channel entrance, are in progress. Results are presented.

  7. Simulations of Beam Quality in a 13 MeV PET Cyclotron

    Directory of Open Access Journals (Sweden)

    A. Pramudita

    2015-12-01

    Full Text Available Simulation of the trajectories of negative hydrogen ion (H− beam in a 13 MeV PET cyclotron (DECY-13 were carried out by using the Runge-Kutta (RK4 approximation method and Scilab 5.4.1. The magnetic and electric fields were calculated using Opera-3d/TOSCA softwares at 1 mm resolution. The cyclotron is of a fourth-harmonics type, meaning that the acceleration occurs four times per cycle, with a radiofrequency (RF field of 77.66 MHz frequency and 40 kV amplitude. The calculations and simulations show that the maximum distance between the ion source and the puller is about 6 mm, while the maximum width of the beam at 13 MeV is about 10 mm, and the initial phase between the RF field and the beam ranges from -10° to 10°, with a yield of about 10% of the beam from the ion source getting accelerated to 13 MeV.

  8. High-radiation zone design of the FMIT high-density beam transport

    International Nuclear Information System (INIS)

    Creek, K.O.; Liska, D.J.; King, J.D.; Cole, T.R.; Cimabue, A.G.; Robeson, L.P.; Harvey, A.

    1981-03-01

    The Fusion Materials Irradiation Test (FMIT) deuteron linac, operating at 35 MeV and 100 mA continuous duty, is expected to spill 3 μA/m and to lose 10 μA at specific bending-magnet positions. The major impact of this spill will be felt in the High-Energy Beam Transport (HEBT), where many beam-line components must be maintained. A modular design concept, that uses segmented termination panels remotely located from the modules, is being employed. Radiation-hardened quadrupoles can be opened, clam-shell fashion, to release the water-cooled beam tube r replacement if there is beam damage or lithium contamination from the target. Termination panels contain electrical, water, and instrumentation fittings to service the module, and are positioned to allow room for neutron-absorbing shielding between the beamline and the panel. The modular construction allows laboratory prealignment and check-out of all components on a structural carriage and is adaptable to supporting gamma shields. Proper choice of beam tube materials is essential for controlling activation caused by beam spill

  9. Proton beam characterization by proton-induced acoustic emission: simulation studies

    International Nuclear Information System (INIS)

    Jones, K C; Witztum, A; Avery, S; Sehgal, C M

    2014-01-01

    Due to their Bragg peak, proton beams are capable of delivering a targeted dose of radiation to a narrow volume, but range uncertainties currently limit their accuracy. One promising beam characterization technique, protoacoustic range verification, measures the acoustic emission generated by the proton beam. We simulated the pressure waves generated by proton radiation passing through water. We observed that the proton-induced acoustic signal consists of two peaks, labeled α and γ, with two originating sources. The α acoustic peak is generated by the pre-Bragg peak heated region whereas the source of the γ acoustic peak is the proton Bragg peak. The arrival time of the α and γ peaks at a transducer reveals the distance from the beam propagation axis and Bragg peak center, respectively. The maximum pressure is not observed directly above the Bragg peak due to interference of the acoustic signals. Range verification based on the arrival times is shown to be more effective than determining the Bragg peak position based on pressure amplitudes. The temporal width of the α and γ peaks are linearly proportional to the beam diameter and Bragg peak width, respectively. The temporal separation between compression and rarefaction peaks is proportional to the spill time width. The pressure wave expected from a spread out Bragg peak dose is characterized. The simulations also show that acoustic monitoring can verify the proton beam dose distribution and range by characterizing the Bragg peak position to within ∼1 mm. (paper)

  10. Simulation of beam-beam effects in tevatron

    International Nuclear Information System (INIS)

    Mishra, C.S.; Assadi, S.; Talman, R.

    1995-08-01

    The Fermilab accelerator complex is in the middle of an upgrade plan Fermilab III. In the last phase of this upgrade the luminosity of the Tevatron will increase by at least one order of magnitude. In order to keep the number of interactions per crossing manageable for experiments, the number of bunches will be increased from 6 x 6 to 36 x 36 and finally to ∼100 x 100 bunches. The beam dynamics of the Tevatron has been studied from Beam-Beam effect point of view in a ''Strong-Weak'' representation with a single particle being tracked in presence of other beam. This paper describes the beam-beam effect in 6 x 6 operation of Tevatron

  11. Sensitivity of the PEP beam transport line to perturbations

    International Nuclear Information System (INIS)

    Peterson, J.M.; Brown, K.L.

    1979-03-01

    The sensitivity of a beam-transport line to various perturbations determines the extent to which one can simplify component design and relax tolerances. For the PEP injection lines, effects of various fabrication errors, magnet misalignments, and residual gas scattering were studied. Using the TURTLE ray-tracing program, it is found that magnetic-field errors corresponding to a relative sextupole strength in the dipoles of 0.5% and/or a relative sextupole or octupole strength in the quadrupoles of 5% are permissible. This allows relatively loose tolerances in magnet fabrication. Transverse misalignment of a quadrupole by a distance x causes the beam centroid to be displaced downstream by as much as 5x. This requires a quadrupole alignment accuracy of +- 0.5 mm or better. No compensation for the earth's field is necessary because an integral number of optical wavelengths and a short wavelength were used for the design. Analysis shows that beam broadening from multiple coulomb scattering is insignificant for pressures of less than 1/10 torr

  12. Beam transport calculations for BARC-TIFR 14UD pelletron

    International Nuclear Information System (INIS)

    Prasad, K.G.

    1993-01-01

    The 14UD pelletron tandem accelerator installed at Tata Institute of Fundamental Research (TIFR) as a joint BARC-TIFR project, is supplied by National Electrostatic Corporation (NEC), U.S.A. To optimise the parameters of various elements along the beam path, it is essential to work out the beam optics of the entire system. There are various computer codes in use for such calculations. All these codes, except the detailed ray tracing programs, use matrix formulation. Thus each ion optical element is characterised in terms of a transport matrix, whose elements are assumed to be independent of particle trajectory. We have performed only the first order calculations, meaning thereby that no aberrations are included. Further, all calculations are carried out assuming ideal conditions like axial beam injection, perfectly aligned beam line elements, etc. The main code that has been employed in our calculations is based on the one at the Australian National University, Canberra, suitably modified for use with CYBER 170/730 computer at TIFR. However, codes at NEC and Stony Brook were also used for the checking the results. The results of calculations are given and discussed. (author). 2 figs

  13. Simulation of instabilities in the presence of beam feedback

    International Nuclear Information System (INIS)

    Myers, S.; Vancraeynest, J.

    1985-01-01

    The effect of longitudinal and transverse instabilities in electron storage rings is simulated by tracking many superparticles for many turns through a model of a machine lattice. This lattice model is defined by a series of machine elements such as RF stations (including longitudinal and transverse wake fields), beam pick-ups, feedback kicker magnets, etc. The machine elements may be interconnected in any specified way so as to produce for example feedback on the longitudinal or transverse beam motion. Each superparticle is treated in six-dimensional phase space and the effects of quantum excitation and radiation damping are included. Insofar as possible the program has been structured to allow study of all known single-beam effects (such as synchro-betatron resonances, transverse mode coupling etc.) in the presence or the absence of some form of beam feedback. The primary goal of the program was to study the effect of a reactive beam feedback system on the threshold for transverse mode coupling. (orig.)

  14. BEAMPATH: a program library for beam dynamics simulation in linear accelerators

    International Nuclear Information System (INIS)

    Batygin, Y.K.

    1992-01-01

    A structured programming technique was used to develop software for space charge dominated beams investigation in linear accelerators. The method includes hierarchical program design using program independent modules and a flexible combination of modules to provide a most effective version of structure for every specific case of simulation. A modular program BEAMPATH was developed for 2D and 3D particle-in-cell simulation of beam dynamics in a structure containing RF gaps, radio-frequency quadrupoles (RFQ), multipole lenses, waveguides, bending magnets and solenoids. (author) 5 refs.; 2 figs

  15. Three dimensional PIC simulation of heavy ion fusion beams: Recent improvements to and applications of WARP

    International Nuclear Information System (INIS)

    Grote, D.P.; Friedman, A.; Haber, I.

    1993-01-01

    The multi-dimensional particle simulation code WARP is used to study the transport and acceleration of space-charge dominated ion beams in present-day and near-term experiments, and in fusion drivers. The algorithms employed in the 3d package and a number of applications have recently been described. In this paper the authors review the general features and major applications of the code. They then present recent developments in both code capabilities and applications. Most notable is modeling of the planned ESQ injector for ILSE, which uses the code's newest features, including subgrid-scale placement of internal conductor boundaries

  16. Beam density equalization in a channel with nonlinear optics

    International Nuclear Information System (INIS)

    Batygin, Yu.K.; Kushin, V.V.; Nesterov, N.A.; Plotnikov, S.V.

    1993-01-01

    Simulation of beam density equalization in 2.85 m length transport channel covering two quadrupole lenses and two octupole lenses was carried out to obtain irradiation homogeneous field of track membrane materials. 0.3 MeV/nucleon energy and 1/8 electron-charge-mass ratio ion beam was supplied to the system inlet. Equalization of beam density function equal to about 80% was obtained. 4 refs., 1 fig

  17. PARALLEL MEASUREMENT AND MODELING OF TRANSPORT IN THE DARHT II BEAMLINE ON ETA II

    International Nuclear Information System (INIS)

    Chambers, F W; Raymond, B A; Falabella, S; Lee, B S; Richardson, R A; Weir, J T; Davis, H A; Schultze, M E

    2005-01-01

    To successfully tune the DARHT II transport beamline requires the close coupling of a model of the beam transport and the measurement of the beam observables as the beam conditions and magnet settings are varied. For the ETA II experiment using the DARHT II beamline components this was achieved using the SUICIDE (Simple User Interface Connecting to an Integrated Data Environment) data analysis environment and the FITS (Fully Integrated Transport Simulation) model. The SUICIDE environment has direct access to the experimental beam transport data at acquisition and the FITS predictions of the transport for immediate comparison. The FITS model is coupled into the control system where it can read magnet current settings for real time modeling. We find this integrated coupling is essential for model verification and the successful development of a tuning aid for the efficient convergence on a useable tune. We show the real time comparisons of simulation and experiment and explore the successes and limitations of this close coupled approach

  18. Optical design of the National Ignition Facility main laser and switchyard/target area beam transport systems

    Science.gov (United States)

    Miller, John L.; English, R. Edward, Jr.; Korniski, Ronald J.; Rodgers, J. Michael

    1999-07-01

    The optical design of the main laser and transport mirror sections of the National Ignition Facility are described. For the main laser the configuration, layout constraints, multiple beam arrangement, pinhole layout and beam paths, clear aperture budget, ray trace models, alignment constraints, lens designs, wavefront performance, and pupil aberrations are discussed. For the transport mirror system the layout, alignment controls and clear aperture budget are described.

  19. Fokker--Planck/transport analyses of fusion plasmas in contemporary beam-driven tokamaks

    International Nuclear Information System (INIS)

    Mirin, A.A.; McCoy, M.G.; Killeen, J.; Rensink, M.E.; Shumaker, D.E.; Jassby, D.L.; Post, D.E.

    1978-04-01

    The properties of deuterium plasmas in experimental tokamaks heated and fueled by intense neutral-beam injection are evaluated with a Fokker-Planck/radial transport code coupled with a Monte Carlo neutrals treatment. Illustrative results are presented for the Poloidal Divertor Experiment at PPPL as a function of beam power and plasma recycling coefficient, R/sub c/. When P/sub beam/ = 8 MW at E/sub b/ = 60 keV, and R/sub c/ = 0.2, then approximately 0.5, [ 2 / 3 ] = 22 keV approximately 6 , and the D-D neutron intensity is 10 16 n/sec

  20. Electronic transport in helium-ion-beam etched encapsulated graphene nanoribbons

    NARCIS (Netherlands)

    Nanda, G.; Hlawacek, Gregor; Goswami, S.; Watanabe, Kenji; Taniguchi, Takashi; Alkemade, P.F.A.

    2017-01-01

    We report the etching of and electronic transport in nanoribbons of graphene sandwiched between atomically flat hexagonal boron nitride (h-BN). The etching of ribbons of varying width was achieved with a focused beam of 30 keV He+ ions. Using in-situ electrical measurements, we

  1. Nanoscale radiation transport and clinical beam modeling for gold nanoparticle dose enhanced radiotherapy (GNPT) using X-rays.

    Science.gov (United States)

    Zygmanski, Piotr; Sajo, Erno

    2016-01-01

    We review radiation transport and clinical beam modelling for gold nanoparticle dose-enhanced radiotherapy using X-rays. We focus on the nanoscale radiation transport and its relation to macroscopic dosimetry for monoenergetic and clinical beams. Among other aspects, we discuss Monte Carlo and deterministic methods and their applications to predicting dose enhancement using various metrics.

  2. Simulation study of LYSO crystal pixels for In-Beam TOF-PET prototype

    International Nuclear Information System (INIS)

    Chen Ze; Hu Zhengguo; Chen Jinda; Zhang Xiuling

    2014-01-01

    In-beam TOF-PET is currently the only feasible method implemented for in-situ and noninvasive monitoring of the precision of the treatment in highly conformal ion radiotherapy. It ensures the safety of patient and accurate implementation of treatment plan. Therefore, we intent to carry out the development of In-beam TOF-PET prototype, which is made of LYSO crystal, for ion radiotherapy. LYSO crystal has perfect properties such as high light yield, fast decay time, good energy and time resolution, which makes it a good candidate. In the development of positron emission tomography (PET) detectors, understanding and optimizing scintillator light collection and energy resolution is critical for achieving high performance, particularly when the design incorporates depth-of-interaction (DOI) encoding or time-of-flight information. Monte Carlo simulations play an important role in guiding research in detector designs and popular software such as Gate now include models of light transport in scintillators. This study uses Gate software to investigate the influence of crystal length and wrapping materials to the light collection. Accurate physical modeling of scintillation detection process, from scintillation light generation through detection, is devised and performed for varying detector attributes, such as the crystal pixel length, light yield, decay time, attenuation length and surface treatment. The dependence of light output and energy resolution is studied and compared with experiment results. The results show that LYSO pixel with length of 5 mm has better light yield and energy resolution, meanwhile prove that it is possible to accurately simulate the light output using Gate. (authors)

  3. DC proton beam measurements in a single-solenoid low-energy beam transport system

    International Nuclear Information System (INIS)

    Stevens, R.R. Jr.; Schafstall, P.; Schneider, J.D.; Sherman, J.; Zaugg, T.; Taylor, T.

    1994-01-01

    High current, CW proton accelerators are being considered for a number of applications including disposition of nuclear wastes, reduction of fissionable nuclear material inventories, safe production of critical nuclear materials, and energy production. All these applications require the development of high current, reliable, hydrogen ion injectors. In 1986, a program using CW RFQ technology was undertaken at CRL in collaboration with LANL and was continued there until 1993. During this time, an accelerator was built which produced 600 keV, 75 mA and 1,250 keV, 55 mA CW proton beams. The present program at Los Alamos using this accelerator is aimed at continuing the CRL work to demonstrate long-term reliability. In the present work, the authors are seeking to determine the optimal match to and the current limit of the 1,250-keV RFQ. This paper discusses the characterization of the 50 keV beams at the exit of the single-solenoid LEBT and presents both the experimental measurements and the beam simulations done to model this system

  4. Light beam tracing for multi-bounce specular and glossy transport paths

    CSIR Research Space (South Africa)

    Duvenhage, B

    2014-09-01

    Full Text Available This paper describes a new extension to light beam tracing that includes glossy multi-bounce transport paths for more realistic rendering of caustics. A spherical Gaussian approximation of the glossy scatter distribution as well as Gauss' divergence...

  5. Open boundaries for particle beams within fit-simulations

    International Nuclear Information System (INIS)

    Balk, M.C.; Schuhmann, R.; Weiland, T.

    2006-01-01

    A method is proposed to simulate open boundary conditions for charged particle beams with v< c in time domain or frequency domain within the Finite Integration Technique (FIT). Inside the calculation domain the moving charged particles are represented by a line current. Further, the simulated field components at the boundary of the calculation domain have to be modified for an undisturbed transmission of the space-charge field. This can be realised by a 'scattered field' formulation. The method is verified by several calculations

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

    International Nuclear Information System (INIS)

    Chiping Chen

    2006-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Chiping Chen

    2006-10-26

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

  8. Development of 2D particle-in-cell code to simulate high current, low ...

    Indian Academy of Sciences (India)

    Abstract. A code for 2D space-charge dominated beam dynamics study in beam trans- port lines is developed. The code is used for particle-in-cell (PIC) simulation of z-uniform beam in a channel containing solenoids and drift space. It can also simulate a transport line where quadrupoles are used for focusing the beam.

  9. Toroidal ripple transport of beam ions in the mega-ampère spherical tokamak

    International Nuclear Information System (INIS)

    McClements, K. G.; Hole, M. J.

    2012-01-01

    The transport of injected beam ions due to toroidal magnetic field ripple in the mega-ampère spherical tokamak (MAST) is quantified using a full orbit particle tracking code, with collisional slowing-down and pitch-angle scattering by electrons and bulk ions taken into account. It is shown that the level of ripple losses is generally rather low, although it depends sensitively on the major radius of the outer midplane plasma edge; for typical values of this parameter in MAST plasmas, the reduction in beam heating power due specifically to ripple transport is less than 1%, and the ripple contribution to beam ion diffusivity is of the order of 0.1 m 2 s –1 or less. It is concluded that ripple effects make only a small contribution to anomalous transport rates that have been invoked to account for measured neutron rates and plasma stored energies in some MAST discharges. Delayed (non-prompt) losses are shown to occur close to the outer midplane, suggesting that banana-drift diffusion is the most likely cause of the ripple-induced losses.

  10. Global gyrokinetic simulation of tokamak transport

    International Nuclear Information System (INIS)

    Furnish, G.; Horton, W.; Kishimoto, Y.; LeBrun, M.J.; Tajima, T.

    1998-10-01

    A kinetic simulation code based on the gyrokinetic ion dynamics in global general metric (including a tokamak with circular or noncircular cross-section) has been developed. This gyrokinetic simulation is capable of examining the global and semi-global driftwave structures and their associated transport in a tokamak plasma. The authors investigate the property of the ion temperature gradient (ITG) or η i (η i ≡ ∂ ell nT i /∂ ell n n i ) driven drift waves in a tokamak plasma. The emergent semi-global drift wave modes give rise to thermal transport characterized by the Bohm scaling

  11. Simulation of the beam guiding of the SAPHIR experiment by means of a differential-equation model

    International Nuclear Information System (INIS)

    Greve, T.

    1991-08-01

    This paper shows the numerical simulation of a beam line by means of a model of differential equations simulating the beam line from the Bonn Electron Stretcher Accelerator ELSA to the SAPHIR spectrometer. Furthermore a method for calculating the initial values based on measurements of beam profiles is being discussed. (orig.) [de

  12. Full three-dimensional simulation of focused ion beam micro/nanofabrication

    International Nuclear Information System (INIS)

    Kim, Heung-Bae; Hobler, Gerhard; Steiger, Andreas; Lugstein, Alois; Bertagnolli, Emmerich

    2007-01-01

    2D focused ion beam simulation is only capable of simulating the topography where the surface shape does not change along the third dimension, both in the final result and during processing. In this paper we show that a 3D topography forms under the beam even though the variation in the final result along the third direction is small. We present the code AMADEUS 3D (advanced modelling and design environment for sputter processes), which is capable of simulating the surface topography in 3D space including angle-dependent sputtering and redeposition. The surface is represented by a structured or unstructured grid, and the nodes are moved according to the calculated sputtering and redeposition fluxes. In addition, experiments have been performed on nanodot formation and box milling for a case where a 3D temporary topography forms. The excellent agreement validates the code and shows the completeness of the model

  13. Linac4 low energy beam measurements with negative hydrogen ions

    Energy Technology Data Exchange (ETDEWEB)

    Scrivens, R., E-mail: richard.scrivens@cern.ch; Bellodi, G.; Crettiez, O.; Dimov, V.; Gerard, D.; Granemann Souza, E.; Guida, R.; Hansen, J.; Lallement, J.-B.; Lettry, J.; Lombardi, A.; Midttun, Ø.; Pasquino, C.; Raich, U.; Riffaud, B.; Roncarolo, F.; Valerio-Lizarraga, C. A.; Wallner, J.; Yarmohammadi Satri, M.; Zickler, T. [CERN, 1211 Geneva 23 (Switzerland)

    2014-02-15

    Linac4, a 160 MeV normal-conducting H{sup −} linear accelerator, is the first step in the upgrade of the beam intensity available from the LHC proton injectors at CERN. The Linac4 Low Energy Beam Transport (LEBT) line from the pulsed 2 MHz RF driven ion source, to the 352 MHz RFQ (Radiofrequency Quadrupole) has been built and installed at a test stand, and has been used to transport and match to the RFQ a pulsed 14 mA H{sup −} beam at 45 keV. A temporary slit-and-grid emittance measurement system has been put in place to characterize the beam delivered to the RFQ. In this paper a description of the LEBT and its beam diagnostics is given, and the results of beam emittance measurements and beam transmission measurements through the RFQ are compared with the expectation from simulations.

  14. Open boundaries for particle beams within fit-simulations

    Energy Technology Data Exchange (ETDEWEB)

    Balk, M.C. [Technische Universitaet Darmstadt, Institut fuer Theorie Elektromagnetischer Felder, Schlossgartenstr. 8, 64289 Darmstadt (Germany)]. E-mail: balk@temf.tu-darmstadt.de; Schuhmann, R. [Technische Universitaet Darmstadt, Institut fuer Theorie Elektromagnetischer Felder, Schlossgartenstr. 8, 64289 Darmstadt (Germany); Weiland, T. [Technische Universitaet Darmstadt, Institut fuer Theorie Elektromagnetischer Felder, Schlossgartenstr. 8, 64289 Darmstadt (Germany)

    2006-03-01

    A method is proposed to simulate open boundary conditions for charged particle beams with vsimulated field components at the boundary of the calculation domain have to be modified for an undisturbed transmission of the space-charge field. This can be realised by a 'scattered field' formulation. The method is verified by several calculations.

  15. Calculation of beam quality correction factor using Monte Carlo simulation

    International Nuclear Information System (INIS)

    Kawachi, T.; Saitoh, H.; Myojoyama, A.; Katayose, T.; Kojima, T.; Fukuda, K.; Inoue, M.

    2005-01-01

    In recent years, a number of the CyberKnife systems (Accuray C., U.S.) have been increasing significantly. However, the CyberKnife has unique treatment head structure and beam collimating system. Therefore, the global standard protocols can not be adopted for absolute absorbed dose dosimetry in CyberKnife beam. In this work, the energy spectrum of photon and electron from CyberKnife treatment head at 80 cm SSD and several depths in water are simulated with conscientious geometry using by the EGS Monte Carlo method. Furthermore, for calculation of the beam quality correction factor k Q , the mean restricted mass stopping power and the mass energy absorption coefficient of air, water and several chamber wall and waterproofing sleeve materials are calculated. As a result, the factors k Q CyberKnife beam for several ionization chambers are determined. And the relationship between the beam quality index PDD(10) x in CyberKnife beam and k Q is described in this report. (author)

  16. Simulations of S-band RF gun with RF beam control

    Science.gov (United States)

    Barnyakov, A. M.; Levichev, A. E.; Maltseva, M. V.; Nikiforov, D. A.

    2017-08-01

    The RF gun with RF control is discussed. It is based on the RF triode and two kinds of the cavities. The first cavity is a coaxial cavity with cathode-grid assembly where beam bunches are formed, the second one is an accelerating cavity. The features of such a gun are the following: bunched and relativistic beams in the output of the injector, absence of the back bombarding electrons, low energy spread and short length of the bunches. The scheme of the injector is shown. The electromagnetic field simulation and longitudinal beam dynamics are presented. The possible using of the injector is discussed.

  17. Beam dynamics simulations of the injector for a compact THz source

    Science.gov (United States)

    Li, Ji; Pei, Yuan-Ji; Shang, Lei; Feng, Guang-Yao; Hu, Tong-Ning; Chen, Qu-Shan; Li, Cheng-Long

    2014-08-01

    Terahertz radiation has broad application prospects due to its ability to penetrate deep into many organic materials without the damage caused by ionizing radiations. A free electron laser (FEL)-based THz source is the best choice to produce high-power radiation. In this paper, a 14 MeV injector is introduced for generating high-quality beam for FEL, is composed of an EC-ITC RF gun, compensating coils and a travelling-wave structure. Beam dynamics simulations have been done with ASTRA code to verify the design and to optimize parameters. Simulations of the operating mode at 6 MeV have also been executed.

  18. Theoretical and computational analysis of IFR beam transport on curved channels

    International Nuclear Information System (INIS)

    Rienstra, W.W.

    1987-01-01

    With the successful demonstration at Sandia National Laboratory and at Lawrence Livermore Laboratory of ion focused regime (IFR) electron beam guiding in accelerators there has developed interest in using IFR channels to steer beams along curved paths. The authors report the calculations of the expected emittance growth from such channels and the results of the TRACKER code simulations of IFR steering with the assistance of strong focus sector magnets

  19. Relativistic electron beams above thunderclouds

    DEFF Research Database (Denmark)

    Füellekrug, M.; Roussel-Dupre, R.; Symbalisty, E. M. D.

    2011-01-01

    Non-luminous relativistic electron beams above thunderclouds have been detected by the radio signals of low frequency similar to 40-400 kHz which they radiate. The electron beams occur similar to 2-9 ms after positive cloud-to-ground lightning discharges at heights between similar to 22-72 km above...... thunderclouds. Intense positive lightning discharges can also cause sprites which occur either above or prior to the electron beam. One electron beam was detected without any luminous sprite which suggests that electron beams may also occur independently of sprites. Numerical simulations show that beams...... of electrons partially discharge the lightning electric field above thunderclouds and thereby gain a mean energy of similar to 7MeV to transport a total charge of similar to-10mC upwards. The impulsive current similar to 3 x 10(-3) Am-2 associated with relativistic electron beams above thunderclouds...

  20. Characteristics of Sissi beams in the transport lines of Ganil

    International Nuclear Information System (INIS)

    Nghiem, P.; Payet, J.; Tkatchenko, A.

    1994-01-01

    This study is the following of the Sissi primary beam characteristics definition. Its aim is to determine the performances in resolution and in transmission of transport lines which guide the secondary beams until the experimentation rooms. The first part concerns the study of the secondary order characteristics with the help of BETA matrix code for the nominal case. The second part is the same study but but of superior orders carried out with the Zgoubi program. The third part consists to search new regulating to minimise the losses of particles due to the effect of non-linearity. (O.L.). 3 refs., 34 figs., 5 tabs

  1. The application of Lie algebra techniques to beam transport design

    International Nuclear Information System (INIS)

    Irwin, J.

    1990-01-01

    Using a final focus system for high-energy linear colliders as an example of a beam transport system, we illustrate for each element, and for the interplay of elements, the connection of Lie algebra techniques with usual optical analysis methods. Our analysis describes, through fourth order, the calculation and compensation of all important aberrations. (orig.)

  2. Fast Poisson Solvers for Self-Consistent Beam-Beam and Space-Charge Field Computation in Multiparticle Tracking Simulations

    CERN Document Server

    Florio, Adrien; Pieloni, Tatiana; CERN. Geneva. ATS Department

    2015-01-01

    We present two different approaches to solve the 2-dimensional electrostatic problem with open boundary conditions to be used in fast tracking codes for beam-beam and space charge simulations in high energy accelerators. We compare a fast multipoles method with a hybrid Poisson solver based on the fast Fourier transform and finite differences in polar coordinates. We show that the latter outperforms the first in terms of execution time and precision, allowing for a reduction of the noise in the tracking simulation. Furthermore the new algorithm is shown to scale linearly on parallel architectures with shared memory. We conclude by effectively replacing the HFMM by the new Poisson solver in the COMBI code.

  3. Simulation of 10 A electron-beam formation and collection for a high current electron-beam ion source

    Science.gov (United States)

    Kponou, A.; Beebe, E.; Pikin, A.; Kuznetsov, G.; Batazova, M.; Tiunov, M.

    1998-02-01

    Presented is a report on the development of an electron-beam ion source (EBIS) for the relativistic heavy ion collider at Brookhaven National Laboratory (BNL) which requires operating with a 10 A electron beam. This is approximately an order of magnitude higher current than in any existing EBIS device. A test stand is presently being designed and constructed where EBIS components will be tested. It will be reported in a separate paper at this conference. The design of the 10 A electron gun, drift tubes, and electron collector requires extensive computer simulations. Calculations have been performed at Novosibirsk and BNL using two different programs, SAM and EGUN. Results of these simulations will be presented.

  4. Breakdown simulations in a focused microwave beam within the simplified model

    International Nuclear Information System (INIS)

    Semenov, V. E.; Rakova, E. I.; Glyavin, M. Yu.; Nusinovich, G. S.

    2016-01-01

    The simplified model is proposed to simulate numerically air breakdown in a focused microwave beam. The model is 1D from the mathematical point of view, but it takes into account the spatial non-uniformity of microwave field amplitude along the beam axis. The simulations are completed for different frequencies and different focal lengths of microwave beams. The results demonstrate complicated regimes of the breakdown evolution which represents a series of repeated ionization waves. These waves start at the focal point and propagate towards incident microwave radiation. The ionization wave parameters vary during propagation. At relatively low frequencies, the propagation regime of subsequent waves can also change qualitatively. Each next ionization wave is less pronounced than the previous one, and the breakdown evolution approaches the steady state with relatively small plasma density. The ionization wave parameters are sensitive to the weak source of external ionization, but the steady state is independent on such a source. As the beam focal length decreases, the stationary plasma density increases and the onset of the steady state occurs faster.

  5. Parallelization of a beam dynamics code and first large scale radio frequency quadrupole simulations

    Directory of Open Access Journals (Sweden)

    J. Xu

    2007-01-01

    Full Text Available The design and operation support of hadron (proton and heavy-ion linear accelerators require substantial use of beam dynamics simulation tools. The beam dynamics code TRACK has been originally developed at Argonne National Laboratory (ANL to fulfill the special requirements of the rare isotope accelerator (RIA accelerator systems. From the beginning, the code has been developed to make it useful in the three stages of a linear accelerator project, namely, the design, commissioning, and operation of the machine. To realize this concept, the code has unique features such as end-to-end simulations from the ion source to the final beam destination and automatic procedures for tuning of a multiple charge state heavy-ion beam. The TRACK code has become a general beam dynamics code for hadron linacs and has found wide applications worldwide. Until recently, the code has remained serial except for a simple parallelization used for the simulation of multiple seeds to study the machine errors. To speed up computation, the TRACK Poisson solver has been parallelized. This paper discusses different parallel models for solving the Poisson equation with the primary goal to extend the scalability of the code onto 1024 and more processors of the new generation of supercomputers known as BlueGene (BG/L. Domain decomposition techniques have been adapted and incorporated into the parallel version of the TRACK code. To demonstrate the new capabilities of the parallelized TRACK code, the dynamics of a 45 mA proton beam represented by 10^{8} particles has been simulated through the 325 MHz radio frequency quadrupole and initial accelerator section of the proposed FNAL proton driver. The results show the benefits and advantages of large-scale parallel computing in beam dynamics simulations.

  6. Simulation and interpretation of ion beam diagnostics on PBFA-II

    International Nuclear Information System (INIS)

    Mehlhorn, T.A.; Nelson, W.E.; Maenchen, J.E.; Stygar, W.A.; Ruiz, C.L.; Lockner, T.R.; Johnson, D.J.

    1988-03-01

    Ion diode and beam focusing experiments are in progress on PBFA-II working towards an ultimate goal of significant burn of an ICF pellet. Beam diagnostics on these experiments include a Thomson parabola, K/sub alpha/ x-ray pinhole cameras, filtered ion pinhole cameras, and a magnetic spectrometer. We are developing two new computer programs to simulate and interpret the data obtained from these diagnostics. VIDA is a VAX-based program that manipulates and unfolds data from digitized particle and x-ray diagnostic images. VIDA operations include: image display, background substraction, relative-to-absolute coordinate transformations, and image projection into the beam reference frame. PICDIAG allows us to study the effects of time-dependent ion focusing on the performance of ion beam diagnostics. 10 refs., 5 figs

  7. X-ray beam transfer between hollow fibers for long-distance transport

    International Nuclear Information System (INIS)

    Tanaka, Yoshihito; Matsushita, Ryuki; Shiraishi, Ryutaro; Hasegawa, Takayuki; Ishikawa, Kiyoshi; Sawada, Kei; Kohmura, Yoshiki; Takahashi, Isao

    2016-01-01

    Fiber optics for controlling the x-ray beam trajectory has been examined at the synchrotron facility of SPring-8. Up to now, we have achieved beam deflection by several tens of milli-radian and axis shift of around 75 mm with a 1.5 m-long flexible hollow glass capillary. The achievable beam deflecting angle, axis shift, and timing delay are, in principle, proportional to the length, the square of length and the cube of length, respectively. Thus, for further applications, requiring larger beam shift and pulse delay, longer fibers are indispensable. In order to achieve long-distance transport using the fiber, we thus examined the connection transferring x-rays between fibers in an experimental hutch. The acceptance angle at the input end and the throughput efficiency of the second fiber is consistent with the consideration of the output beam divergence of the first fiber. The enhancement of the transfer efficiency is also discussed for the cases of a closer joint and the use of a refractive lens as a coupler.

  8. X-ray beam transfer between hollow fibers for long-distance transport

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Yoshihito, E-mail: tanaka@sci.u-hyogo.ac.jp; Matsushita, Ryuki; Shiraishi, Ryutaro; Hasegawa, Takayuki; Ishikawa, Kiyoshi [Graduate School of Material Science, University of Hyogo, 3-2-1 Kouto, Kamigori-cho, Sayo-gun, Hyogo 678-1297 (Japan); Sawada, Kei; Kohmura, Yoshiki [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Takahashi, Isao [Department of Physics, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337 Japan (Japan)

    2016-07-27

    Fiber optics for controlling the x-ray beam trajectory has been examined at the synchrotron facility of SPring-8. Up to now, we have achieved beam deflection by several tens of milli-radian and axis shift of around 75 mm with a 1.5 m-long flexible hollow glass capillary. The achievable beam deflecting angle, axis shift, and timing delay are, in principle, proportional to the length, the square of length and the cube of length, respectively. Thus, for further applications, requiring larger beam shift and pulse delay, longer fibers are indispensable. In order to achieve long-distance transport using the fiber, we thus examined the connection transferring x-rays between fibers in an experimental hutch. The acceptance angle at the input end and the throughput efficiency of the second fiber is consistent with the consideration of the output beam divergence of the first fiber. The enhancement of the transfer efficiency is also discussed for the cases of a closer joint and the use of a refractive lens as a coupler.

  9. 1D numerical simulation of charge trapping in an insulator submitted to an electron beam irradiation. Part I: Computation of the initial secondary electron emission yield

    International Nuclear Information System (INIS)

    Aoufi, A.; Damamme, G.

    2011-01-01

    The aim of this work is to study by numerical simulation a mathematical modelling technique describing charge trapping during initial charge injection in an insulator submitted to electron beam irradiation. A two-fluxes method described by a set of two stationary transport equations is used to split the electron current j e (z) into coupled forward j e+ (z) and backward j e (z) currents and such that j e (z) = j e+ (z) - j e- (z). The sparse algebraic linear system, resulting from the vertex-centered finite-volume discretization scheme is solved by an iterative decoupled fixed point method which involves the direct inversion of a bi-diagonal matrix. The sensitivity of the initial secondary electron emission yield with respect to the energy of incident primary electrons beam, that is penetration depth of the incident beam, or electron cross sections (absorption and diffusion) is investigated by numerical simulations. (authors)

  10. Multi-grid Beam and Warming scheme for the simulation of unsteady ...

    African Journals Online (AJOL)

    In this paper, a multi-grid algorithm is applied to a large-scale block matrix that is produced from a Beam and Warming scheme. The Beam and Warming scheme is used in the simulation of unsteady flow in an open channel. The Gauss-Seidel block-wise iteration method is used for a smoothing process with a few iterations.

  11. The determination of beam quality correction factors: Monte Carlo simulations and measurements.

    Science.gov (United States)

    González-Castaño, D M; Hartmann, G H; Sánchez-Doblado, F; Gómez, F; Kapsch, R-P; Pena, J; Capote, R

    2009-08-07

    Modern dosimetry protocols are based on the use of ionization chambers provided with a calibration factor in terms of absorbed dose to water. The basic formula to determine the absorbed dose at a user's beam contains the well-known beam quality correction factor that is required whenever the quality of radiation used at calibration differs from that of the user's radiation. The dosimetry protocols describe the whole ionization chamber calibration procedure and include tabulated beam quality correction factors which refer to 60Co gamma radiation used as calibration quality. They have been calculated for a series of ionization chambers and radiation qualities based on formulae, which are also described in the protocols. In the case of high-energy photon beams, the relative standard uncertainty of the beam quality correction factor is estimated to amount to 1%. In the present work, two alternative methods to determine beam quality correction factors are prescribed-Monte Carlo simulation using the EGSnrc system and an experimental method based on a comparison with a reference chamber. Both Monte Carlo calculations and ratio measurements were carried out for nine chambers at several radiation beams. Four chamber types are not included in the current dosimetry protocols. Beam quality corrections for the reference chamber at two beam qualities were also measured using a calorimeter at a PTB Primary Standards Dosimetry Laboratory. Good agreement between the Monte Carlo calculated (1% uncertainty) and measured (0.5% uncertainty) beam quality correction factors was obtained. Based on these results we propose that beam quality correction factors can be generated both by measurements and by the Monte Carlo simulations with an uncertainty at least comparable to that given in current dosimetry protocols.

  12. Simulation of Heavily Irradiated Silicon Pixel Sensors and Comparison with Test Beam Measurements

    CERN Document Server

    Chiochia, Vincenzo; Bortoletto, Daniela; Cremaldi, Lucien; Cucciarelli, Susanna; Dorokhov, Andrei; Hoermann, Christoph; Kim, Dongwook; Konecki, Marcin; Kotlinski, Danek; Prokofiev, Kirill; Regenfus, Christian; Rohe, Tilman; Sanders, David A.; Son, Seunghee; Speer, Thomas; Chiochia, Vincenzo; Swartz, Morris; Bortoletto, Daniela; Cremaldi, Lucien; Cucciarelli, Susanna; Dorokhov, Andrei; Hoermann, Christoph; Kim, Dongwook; Konecki, Marcin; Kotlinski, Danek; Prokofiev, Kirill; Regenfus, Christian; Rohe, Tilman; Sanders, David A.; Son, Seunghee; Speer, Thomas

    2004-01-01

    Charge collection measurements performed on heavily irradiated p-spray DOFZ pixel sensors with a grazing angle hadron beam provide a sensitive determination of the electric field within the detectors. The data are compared with a complete charge transport simulation of the sensor which includes signal trapping and charge induction effects. A linearly varying electric field based upon the standard picture of a constant type-inverted effective doping density is inconsistent with the data. A two-trap double junction model implemented in the ISE TCAD software can be tuned to produce a doubly-peaked electric field which describes the data reasonably well. The modeled field differs somewhat from previous determinations based upon the transient current technique. The model can also account for the level of charge trapping observed in the data.

  13. Application of Chebyshev Formalism to Identify Nonlinear Magnetic Field Components in Beam Transport Systems

    Energy Technology Data Exchange (ETDEWEB)

    Spata, Michael [Old Dominion Univ., Norfolk, VA (United States)

    2012-08-01

    An experiment was conducted at Jefferson Lab's Continuous Electron Beam Accelerator Facility to develop a beam-based technique for characterizing the extent of the nonlinearity of the magnetic fields of a beam transport system. Horizontally and vertically oriented pairs of air-core kicker magnets were simultaneously driven at two different frequencies to provide a time-dependent transverse modulation of the beam orbit relative to the unperturbed reference orbit. Fourier decomposition of the position data at eight different points along the beamline was then used to measure the amplitude of these frequencies. For a purely linear transport system one expects to find solely the frequencies that were applied to the kickers with amplitudes that depend on the phase advance of the lattice. In the presence of nonlinear fields one expects to also find harmonics of the driving frequencies that depend on the order of the nonlinearity. Chebyshev polynomials and their unique properties allow one to directly quantify the magnitude of the nonlinearity with the minimum error. A calibration standard was developed using one of the sextupole magnets in a CEBAF beamline. The technique was then applied to a pair of Arc 1 dipoles and then to the magnets in the Transport Recombiner beamline to measure their multipole content as a function of transverse position within the magnets.

  14. The Science of Transportation Analysis and Simulation

    Science.gov (United States)

    Gleibe, John

    2010-03-01

    Transportation Science focuses on methods developed to model and analyze the interaction between human behavior and transportation systems. From the human behavioral, or demand, perspective, we are interested in how person and households organize their activities across space and time, with travel viewed as an enabling activity. We have a particular interest in how to model the range of responses to public policy and transportation system changes, which leads to the consideration of both short- and long-term decision-making, interpersonal dependencies, and non-transportation-related opportunities and constraints, including household budgets, land use systems and economic systems. This has led to the development of complex structural econometric modeling systems as well as agent-based simulations. From the transportation systems, or supply, perspective we are interested in the level of service provide by transportation facilities, be it auto, transit or multi-modal systems. This has led to the development of network models and equilibrium concepts as well as hybrid simulation systems based on concepts borrowed from physics, such as fluid flow models, and cellular automata-type models. In this presentation, we review a representative sample of these methods and their use in transportation planning and public policy analysis.

  15. BEAMR: An interactive graphic computer program for design of charged particle beam transport systems

    Science.gov (United States)

    Leonard, R. F.; Giamati, C. C.

    1973-01-01

    A computer program for a PDP-15 is presented which calculates, to first order, the characteristics of charged-particle beam as it is transported through a sequence of focusing and bending magnets. The maximum dimensions of the beam envelope normal to the transport system axis are continuously plotted on an oscilloscope as a function of distance along the axis. Provision is made to iterate the calculation by changing the types of magnets, their positions, and their field strengths. The program is especially useful for transport system design studies because of the ease and rapidity of altering parameters from panel switches. A typical calculation for a system with eight elements is completed in less than 10 seconds. An IBM 7094 version containing more-detailed printed output but no oscilloscope display is also presented.

  16. Monte Carlo simulation of electron beams from an accelerator head using PENELOPE

    Energy Technology Data Exchange (ETDEWEB)

    Sempau, J. [Institut de Tecniques Energetiques, Universitat Politecnica de Catalunya, Diagonal 647, 08028 Barcelona (Spain). E-mail: josep.sempau@upc.es; Sanchez-Reyes, A. [Servei d' Oncologia Radioterapica, Hospital Clinic de Barcelona, Villarroel 170, 08036 Barcelona (Spain); Institut d' Investigaciones Biomediques August Pi i Sunyer (IDIBAPS), Universitat de Barcelona (Spain); Salvat, F.; Oulad ben Tahar, H.; Fernandez-Varea, J.M. [Facultat de Fisica (ECM), Universitat de Barcelona, Societat Catalana de Fisica (IEC), Diagonal 647, 08028 Barcelona (Spain); Jiang, S.B. [Department of Radiation Oncology, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, CA 94305-5304 (United States)

    2001-04-01

    The Monte Carlo code PENELOPE has been used to simulate electron beams from a Siemens Mevatron KDS linac with nominal energies of 6, 12 and 18 MeV. Owing to its accuracy, which stems from that of the underlying physical interaction models, PENELOPE is suitable for simulating problems of interest to the medical physics community. It includes a geometry package that allows the definition of complex quadric geometries, such as those of irradiation instruments, in a straightforward manner. Dose distributions in water simulated with PENELOPE agree well with experimental measurements using a silicon detector and a monitoring ionization chamber. Insertion of a lead slab in the incident beam at the surface of the water phantom produces sharp variations in the dose distributions, which are correctly reproduced by the simulation code. Results from PENELOPE are also compared with those of equivalent simulations with the EGS4-based user codes BEAM and DOSXYZ. Angular and energy distributions of electrons and photons in the phase-space plane (at the downstream end of the applicator) obtained from both simulation codes are similar, although significant differences do appear in some cases. These differences, however, are shown to have a negligible effect on the calculated dose distributions. Various practical aspects of the simulations, such as the calculation of statistical uncertainties and the effect of the 'latent' variance in the phase-space file, are discussed in detail. (author)

  17. Beam tracking simulation in the central region of a 13 MeV PET cyclotron

    Science.gov (United States)

    Anggraita, Pramudita; Santosa, Budi; Taufik, Mulyani, Emy; Diah, Frida Iswinning

    2012-06-01

    This paper reports the trajectories simulation of proton beam in the central region of a 13 MeV PET cyclotron, operating with negative proton beam (for easier beam extraction using a stripper foil), 40 kV peak accelerating dee voltage at fourth harmonic frequency of 77.88 MHz, and average magnetic field of 1.275 T. The central region covers fields of 240mm × 240mm × 30mm size at 1mm resolution. The calculation was also done at finer 0.25mm resolution covering fields of 30mm × 30mm × 4mm size to see the effects of 0.55mm horizontal width of the ion source window and the halted trajectories of positive proton beam. The simulations show up to 7 turns of orbital trajectories, reaching about 1 MeV of beam energy. The distribution of accelerating electric fields and magnetic fields inside the cyclotron were calculated in 3 dimension using Opera3D code and Tosca modules for static magnetic and electric fields. The trajectory simulation was carried out using Scilab 5.3.3 code.

  18. Antiproton annihilation physics annihilation physics in the Monte Carlo particle transport code particle transport code SHIELD-HIT12A

    DEFF Research Database (Denmark)

    Taasti, Vicki Trier; Knudsen, Helge; Holzscheiter, Michael

    2015-01-01

    The Monte Carlo particle transport code SHIELD-HIT12A is designed to simulate therapeutic beams for cancer radiotherapy with fast ions. SHIELD-HIT12A allows creation of antiproton beam kernels for the treatment planning system TRiP98, but first it must be benchmarked against experimental data. An...

  19. Solenoidal Fields for Ion Beam Transport and Focusing

    International Nuclear Information System (INIS)

    Lee, Edward P.; Leitner, Matthaeus

    2007-01-01

    In this report we calculate time-independent fields of solenoidal magnets that are suitable for ion beam transport and focusing. There are many excellent Electricity and Magnetism textbooks that present the formalism for magnetic field calculations and apply it to simple geometries (1-1), but they do not include enough relevant detail to be used for designing a charged particle transport system. This requires accurate estimates of fringe field aberrations, misaligned and tilted fields, peak fields in wire coils and iron, external fields, and more. Specialized books on magnet design, technology, and numerical computations (1-2) provide such information, and some of that is presented here. The AIP Conference Proceedings of the US Particle Accelerator Schools (1-3) contain extensive discussions of design and technology of magnets for ion beams - except for solenoids. This lack may be due to the fact that solenoids have been used primarily to transport and focus particles of relatively low momenta, e.g. electrons of less than 50 MeV and protons or H- of less than 1.0 MeV, although this situation may be changing with the commercial availability of superconducting solenoids with up to 20T bore field (1-4). Internal reports from federal laboratories and industry treat solenoid design in detail for specific applications. The present report is intended to be a resource for the design of ion beam drivers for Inertial Fusion Energy (1-5) and Warm Dense Matter experiments (1-6), although it should also be useful for a broader range of applications. The field produced by specified currents and material magnetization can always be evaluated by solving Maxwell's equations numerically, but it is also desirable to have reasonably accurate, simple formulas for conceptual system design and fast-running beam dynamics codes, as well as for general understanding. Most of this report is devoted to such formulas, but an introduction to the Tosca(copyright) code (1-7) and some numerical

  20. Computer module for scheduling of transportation of composite beam bridge structures

    Directory of Open Access Journals (Sweden)

    Bożejko Wojciech

    2016-01-01

    Full Text Available The paper presents the theoretical basis, an algorithm and a computer module system supporting scheduling of transportation and assembly of structures of the composite beam bridge implemented in a Just In Time system (JIT. Tabu search method has been used in the optimization procedure.

  1. Biological transportation networks: Modeling and simulation

    KAUST Repository

    Albi, Giacomo

    2015-09-15

    We present a model for biological network formation originally introduced by Cai and Hu [Adaptation and optimization of biological transport networks, Phys. Rev. Lett. 111 (2013) 138701]. The modeling of fluid transportation (e.g., leaf venation and angiogenesis) and ion transportation networks (e.g., neural networks) is explained in detail and basic analytical features like the gradient flow structure of the fluid transportation network model and the impact of the model parameters on the geometry and topology of network formation are analyzed. We also present a numerical finite-element based discretization scheme and discuss sample cases of network formation simulations.

  2. Measurements and simulations of focused beam for orthovoltage therapy

    International Nuclear Information System (INIS)

    Abbas, Hassan; Mahato, Dip N.; Satti, Jahangir; MacDonald, C. A.

    2014-01-01

    Purpose: Megavoltage photon beams are typically used for therapy because of their skin-sparing effect. However, a focused low-energy x-ray beam would also be skin sparing, and would have a higher dose concentration at the focal spot. Such a beam can be produced with polycapillary optics. MCNP5 was used to model dose profiles for a scanned focused beam, using measured beam parameters. The potential of low energy focused x-ray beams for radiation therapy was assessed. Methods: A polycapillary optic was used to focus the x-ray beam from a tungsten source. The optic was characterized and measurements were performed at 50 kV. PMMA blocks of varying thicknesses were placed between optic and the focal spot to observe any variation in the focusing of the beam after passing through the tissue-equivalent material. The measured energy spectrum was used to model the focused beam in MCNP5. A source card (SDEF) in MCNP5 was used to simulate the converging x-ray beam. Dose calculations were performed inside a breast tissue phantom. Results: The measured focal spot size for the polycapillary optic was 0.2 mm with a depth of field of 5 mm. The measured focal spot remained unchanged through 40 mm of phantom thickness. The calculated depth dose curve inside the breast tissue showed a dose peak several centimeters below the skin with a sharp dose fall off around the focus. The percent dose falls below 10% within 5 mm of the focus. It was shown that rotating the optic during scanning would preserve the skin-sparing effect of the focused beam. Conclusions: Low energy focused x-ray beams could be used to irradiate tumors inside soft tissue within 5 cm of the surface

  3. Gyrokinetic particle simulation of neoclassical transport

    International Nuclear Information System (INIS)

    Lin, Z.; Tang, W.M.; Lee, W.W.

    1995-01-01

    A time varying weighting (δf ) scheme for gyrokinetic particle simulation is applied to a steady-state, multispecies simulation of neoclassical transport. Accurate collision operators conserving momentum and energy are developed and implemented. Simulation results using these operators are found to agree very well with neoclassical theory. For example, it is dynamically demonstrated that like-particle collisions produce no particle flux and that the neoclassical fluxes are ambipolar for an ion--electron plasma. An important physics feature of the present scheme is the introduction of toroidal flow to the simulations. Simulation results are in agreement with the existing analytical neoclassical theory. The poloidal electric field associated with toroidal mass flow is found to enhance density gradient-driven electron particle flux and the bootstrap current while reducing temperature gradient-driven flux and current. Finally, neoclassical theory in steep gradient profile relevant to the edge regime is examined by taking into account finite banana width effects. In general, in the present work a valuable new capability for studying important aspects of neoclassical transport inaccessible by conventional analytical calculation processes is demonstrated. copyright 1995 American Institute of Physics

  4. Simulation of energy deposit distribution in water for 10 and 25 MeV electron beams

    International Nuclear Information System (INIS)

    Borrell Carbonell, Maria de los Angeles.

    1977-01-01

    The Monte Carlo method was applied to transport simulation of electron beams from the exit window of a linear accelerator till the absorption by a water phantom. The distribution of energy deposit is calculated for ideal apparatus and experimental conditions. Calculations are made for a distance window-water surface of one meter, for 10 and 25 MeV monoenergetic incident electrons, and for different fields (15x15 cm 2 to 4x4 cm 2 ). Comparisons with experimental measurements obtained in comparable conditions with a Sagittaire accelerator (C.G.R.-MeV), show a good agreement concerning radial distribution and depth distribution around isodose 100%. However a certain disagreement appears in the end of depth penetration [fr

  5. Laser accelerated protons captured and transported by a pulse power solenoid

    Directory of Open Access Journals (Sweden)

    T. Burris-Mog

    2011-12-01

    Full Text Available Using a pulse power solenoid, we demonstrate efficient capture of laser accelerated proton beams and the ability to control their large divergence angles and broad energy range. Simulations using measured data for the input parameters give inference into the phase-space and transport efficiencies of the captured proton beams. We conclude with results from a feasibility study of a pulse power compact achromatic gantry concept. Using a scaled target normal sheath acceleration spectrum, we present simulation results of the available spectrum after transport through the gantry.

  6. End-to-End Beam Simulations for the New Muon G-2 Experiment at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Korostelev, Maxim [Cockcroft Inst. Accel. Sci. Tech.; Bailey, Ian [Lancaster U.; Herrod, Alexander [Liverpool U.; Morgan, James [Fermilab; Morse, William [RIKEN BNL; Stratakis, Diktys [RIKEN BNL; Tishchenko, Vladimir [RIKEN BNL; Wolski, Andrzej [Cockcroft Inst. Accel. Sci. Tech.

    2016-06-01

    The aim of the new muon g-2 experiment at Fermilab is to measure the anomalous magnetic moment of the muon with an unprecedented uncertainty of 140 ppb. A beam of positive muons required for the experiment is created by pion decay. Detailed studies of the beam dynamics and spin polarization of the muons are important to predict systematic uncertainties in the experiment. In this paper, we present the results of beam simulations and spin tracking from the pion production target to the muon storage ring. The end-to-end beam simulations are developed in Bmad and include the processes of particle decay, collimation (with accurate representation of all apertures) and spin tracking.

  7. Focused particle beam nano-machining: the next evolution step towards simulation aided process prediction

    International Nuclear Information System (INIS)

    Plank, Harald

    2015-01-01

    During the last decade, focused ion beam processing has been developed from traditionally used Ga + liquid ion sources towards higher resolution gas field ion sources (He + and Ne + ). Process simulations not only improve the fundamental understanding of the relevant ion–matter interactions, but also enable a certain predictive power to accelerate advances. The historic ‘gold’ standard in ion–solid simulations is the SRIM/TRIM Monte Carlo package released by Ziegler, Ziegler and Biersack 2010 Nucl. Instrum. Methods B 268 1818–23. While SRIM/TRIM is very useful for a myriad of applications, it is not applicable for the understanding of the nanoscale evolution associated with ion beam nano-machining as the substrate does not evolve with the sputtering process. As a solution for this problem, a new, adapted simulation code is briefly overviewed and finally addresses these contributions. By that, experimentally observed Ne + beam sputter profiles can be explained from a fundamental point of view. Due to their very good agreement, these simulations contain the potential for computer aided optimization towards predictable sputter processes for different nanotechnology applications. With these benefits in mind, the discussed simulation approach represents an enormous step towards a computer based master tool for adaptable ion beam applications in the context of industrial applications. (viewpoint)

  8. Beam dynamics simulations of the injector for a compact THz source

    International Nuclear Information System (INIS)

    Li Ji; Pei Yuanji; Shang Lei; Li Chenglong; Feng Guangyao; Hu Tongning; Chen Qushan

    2014-01-01

    Terahertz radiation has broad application prospects due to its ability to penetrate deep into many organic materials without the damage caused by ionizing radiations. A free electron laser (FEL)-based THz source is the best choice to produce high-power radiation. In this paper, a 14 MeV injector is introduced for generating high-quality beam for FEL, is composed of an EC-ITC RF gun, compensating coils and a travelling-wave structure. Beam dynamics simulations have been done with ASTRA code to verify the design and to optimize parameters. Simulations of the operating mode at 6 MeV have also been executed. (authors)

  9. Simulation of 10 A electron-beam formation and collection for a high current electron-beam ion source

    International Nuclear Information System (INIS)

    Kponou, A.; Beebe, E.; Pikin, A.; Kuznetsov, G.; Batazova, M.; Tiunov, M.

    1998-01-01

    Presented is a report on the development of an electron-beam ion source (EBIS) for the relativistic heavy ion collider at Brookhaven National Laboratory (BNL) which requires operating with a 10 A electron beam. This is approximately an order of magnitude higher current than in any existing EBIS device. A test stand is presently being designed and constructed where EBIS components will be tested. It will be reported in a separate paper at this conference. The design of the 10 A electron gun, drift tubes, and electron collector requires extensive computer simulations. Calculations have been performed at Novosibirsk and BNL using two different programs, SAM and EGUN. Results of these simulations will be presented. copyright 1998 American Institute of Physics

  10. Simulation of the interaction of positively charged beams and electron clouds

    International Nuclear Information System (INIS)

    Markovik, Aleksandar

    2013-01-01

    The incoherent (head-tail) effect on the bunch due to the interaction with electron clouds (e-clouds) leads to a blow up of the transverse beam size in storage rings operating with positively charged beams. Even more the e-cloud effects are considered to be the main limiting factor for high current, high-brightness or high-luminosity operation of future machines. Therefore the simulation of e-cloud phenomena is a highly active field of research. The main focus in this work was set to a development of a tool for simulation of the interaction of relativistic bunches with non-relativistic parasitic charged particles. The result is the Particle-In-Cell Program MOEVE PIC Tracking which can track a 3D bunch under the influence of its own and external electromagnetic fields but first and foremost it simulates the interaction of relativistic positively charged bunches and initially static electrons. In MOEVE PIC Tracking the conducting beam pipe can be modeled with an arbitrary elliptical cross-section to achieve more accurate space charge field computations for both the bunch and the e-cloud. The simulation of the interaction between positron bunches and electron clouds in this work gave a detailed insight of the behavior of both particle species during and after the interaction. Further and ultimate goal of this work was a fast estimation of the beam stability under the influence of e-clouds in the storage ring. The standard approach to simulate the stability of a single bunch is to track the bunch particles through the linear optics of the machine by multiplying the 6D vector of each particle with the transformation matrices describing the lattice. Thereby the action of the e-cloud on the bunch is approximated by a pre-computed wake kick which is applied on one or more points in the lattice. Following the idea of K.Ohmi the wake kick was pre-computed as a two variable function of the bunch part exiting the e-cloud and the subsequent parts of a bunch which receive a

  11. Design and performance of the 40 MeV linac and beam transport system for the 1 GeV synchrotron radiation source at SORTEC

    International Nuclear Information System (INIS)

    Shiota, M.; Hiraki, A.; Mizota, M.; Iida, T.; Haraguchi, M.; Kuno, K.; Nakamura, S.; Ohno, M.; Tomimasu, T.

    1990-01-01

    A 1 Gev synchrotron radiation source (SOR) system has been installed and is now being adjusted at SORTEC corporation. This paper reports the configuration and the beam test results of the 40 MeV electron linac (pre-injector) and the beam transport line to the electron synchrotron used in this system. The output beam from the linac must be low emittance, small energy spread, and stable in energy. The beam transport line must also efficiently lead the beam from the linac to the electron synchrotron. This linac produced the beam current of 130 mA, with an energy spread of 1.3 % (FWHM), and an emittance of 0.7 πmm·mrad. The beam characteristics were verified by various beam monitors on the beam transport line. (author)

  12. A system for beams transport from synchrophasotron and nuclotron to experimental set-ups No. 205

    International Nuclear Information System (INIS)

    Barteneva, N.A.; Volobueva, T.I.; Kirillov, A.D.

    1990-01-01

    A scheme for accelerated particle beam trasnport from the MV-1 synchrophasotron and Nuclotron is presented. The positioning of the Nuclotron ring at 3.9 m level relatively to the lines of existing channels conditioned the development of beam vertical extraction system. Beam transport from the Nuclotron or the synchrophasotron to building 205 is ensured through a moving doublet of quadrupoles and magnet mounted on a rotating platform. 1 ref

  13. Radiation Simulations and Development of Concepts for High Power Beam Dumps, Catchers and Pre-separator Area Layouts for the Fragment Separators for RIA

    CERN Document Server

    Ronningen, Reginald; Beene, James R; Blideanu, Valetin; Boles, Jason; Bollen, Georg; Burgess, Thomas; Carter, Ken; Conner, David L; Gabriel, Tony A; Geissel, Hans; Gomes, Itacil C; Heilbronn, Lawrence; Iwase, Hiroshi; Lawton, Don; Levand, Anthony; Mansur, Louis; Momozaki, Yoichi; Morrissey, David; Nolen, Jerry; Reed, Claude; Remec, Igor; Rennich, Mark; Reyes, Susana; Sherrill, Bradley; Stein, Werner; Stoyer, Mark; Stracener, Dan; Wendel, Mark; Zeller, Al

    2005-01-01

    The development of high-power beam dumps and catchers, and pre-separator layouts for proposed fragment separators of the Rare-Isotope Accelerator (RIA) facility are important in realizing how to handle the 400 kW in the primary beam. We will present examples of pre-conceptual designs of beam dumps, fragment catchers, and the pre-separator layout. We will also present examples of ongoing work on radiation simulations using the heavy-ion-transport code PHITS, characterizing the secondary radiation produced by the high-power ion beams interacting with these devices. Results on radiation heating of targets, magnet coils, associated hardware and shielding, component activation, and levels of radiation dose will be presented. These initial studies will yield insight into the impact of the high-power dissipation on fragment separator design, remote handling concepts, nuclear safety and potential facility hazard classification, shielding design, civil construction design, component design, and material choices. Furth...

  14. Simulation of the Beam-Beam Effects in e+e- Storage Rings with a Method of Reducing the Region of Mesh

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Yunhai

    2000-08-31

    A highly accurate self-consistent particle code to simulate the beam-beam collision in e{sup +}e{sup -} storage rings has been developed. It adopts a method of solving the Poisson equation with an open boundary. The method consists of two steps: assigning the potential on a finite boundary using the Green's function, and then solving the potential inside the boundary with a fast Poisson solver. Since the solution of the Poisson's equation is unique, the authors solution is exactly the same as the one obtained by simply using the Green's function. The method allows us to select much smaller region of mesh and therefore increase the resolution of the solver. The better resolution makes more accurate the calculation of the dynamics in the core of the beams. The luminosity simulated with this method agrees quantitatively with the measurement for the PEP-II B-factory ring in the linear and nonlinear beam current regimes, demonstrating its predictive capability in detail.

  15. Design study of a microwave driver for a Relativistic Klystron Two-Beam Accelerator

    International Nuclear Information System (INIS)

    Houck, T.L.

    1993-05-01

    In two-beam accelerators, the reacceleration of a modulated drive beam can enable high conversion efficiency of electron beam energy to rf energy. However, the stability issues involved with the transport of high current electron beams through rf extraction structures and induction accelerator cells are critical. The author reports on theoretical studies and computer simulations of a two-beam accelerator design using traveling-wave extraction structures. Specific issues addressed include regenerative and cumulative transverse instabilities

  16. Temperature fields occurring in dielectric capillaries for the transport of of ion beams

    International Nuclear Information System (INIS)

    Urbanovich, A.I.

    2012-01-01

    This paper presents the results of computing the temperature fields occurring in dielectric capillaries of glass for the transport of accelerated charged particles. It is shown that on the transport of ion beams with a power of several watts the capillary is heated intensively, whereas heat stresses may approach the lower bound associated with a real strength of glass. (authors)

  17. Vibration Control of Flexible Mode for a Beam-Type Substrate Transport Robot

    Directory of Open Access Journals (Sweden)

    Cheol Hoon Park

    2013-07-01

    Full Text Available Beam-type substrate transport robots are widely used to handle substrates, especially in the solar cell manufacturing process. To reduce the takt time and increase productivity, accurate position control becomes increasingly important as the size of the substrate increases. However, the vibration caused by the flexible forks in beam-type robots interferes with accurate positioning, which results in long takt times in the manufacturing process. To minimize the vibration and transport substrates on the fork as fast as possible, the trajectories should be prevented from exciting the flexible modes of the forks. For this purpose, a fifth-order polynomial trajectory generator and input shaping were incorporated into the controller of the beam-type robot in this study. The flexible modes of the forks were identified by measuring the frequency response function (FRF, and the input shaping was designed so as not to excite the flexible modes. The controller was implemented by using MATLAB/xPC Target. In this paper, the design procedure of input shaping and its effectiveness for vibration attenuation in both “no load” and “load” cases is presented.

  18. Optimization of GEANT4 settings for Proton Pencil Beam Scanning simulations using GATE

    Energy Technology Data Exchange (ETDEWEB)

    Grevillot, Loic, E-mail: loic.grevillot@gmail.co [Universite de Lyon, F-69622 Lyon (France); Creatis, CNRS UMR 5220, F-69622 Villeurbanne (France); Centre de Lutte Contre le Cancer Leon Berard, F-69373 Lyon (France); IBA, B-1348 Louvain-la-Neuve (Belgium); Frisson, Thibault [Universite de Lyon, F-69622 Lyon (France); Creatis, CNRS UMR 5220, F-69622 Villeurbanne (France); Centre de Lutte Contre le Cancer Leon Berard, F-69373 Lyon (France); Zahra, Nabil [Universite de Lyon, F-69622 Lyon (France); IPNL, CNRS UMR 5822, F-69622 Villeurbanne (France); Centre de Lutte Contre le Cancer Leon Berard, F-69373 Lyon (France); Bertrand, Damien; Stichelbaut, Frederic [IBA, B-1348 Louvain-la-Neuve (Belgium); Freud, Nicolas [Universite de Lyon, F-69622 Lyon (France); CNDRI, INSA-Lyon, F-69621 Villeurbanne Cedex (France); Sarrut, David [Universite de Lyon, F-69622 Lyon (France); Creatis, CNRS UMR 5220, F-69622 Villeurbanne (France); Centre de Lutte Contre le Cancer Leon Berard, F-69373 Lyon (France)

    2010-10-15

    This study reports the investigation of different GEANT4 settings for proton therapy applications in the context of Treatment Planning System comparisons. The GEANT4.9.2 release was used through the GATE platform. We focused on the Pencil Beam Scanning delivery technique, which allows for intensity modulated proton therapy applications. The most relevant options and parameters (range cut, step size, database binning) for the simulation that influence the dose deposition were investigated, in order to determine a robust, accurate and efficient simulation environment. In this perspective, simulations of depth-dose profiles and transverse profiles at different depths and energies between 100 and 230 MeV have been assessed against reference measurements in water and PMMA. These measurements were performed in Essen, Germany, with the IBA dedicated Pencil Beam Scanning system, using Bragg-peak chambers and radiochromic films. GEANT4 simulations were also compared to the PHITS.2.14 and MCNPX.2.5.0 Monte Carlo codes. Depth-dose simulations reached 0.3 mm range accuracy compared to NIST CSDA ranges, with a dose agreement of about 1% over a set of five different energies. The transverse profiles simulated using the different Monte Carlo codes showed discrepancies, with up to 15% difference in beam widening between GEANT4 and MCNPX in water. A 8% difference between the GEANT4 multiple scattering and single scattering algorithms was observed. The simulations showed the inability of reproducing the measured transverse dose spreading with depth in PMMA, corroborating the fact that GEANT4 underestimates the lateral dose spreading. GATE was found to be a very convenient simulation environment to perform this study. A reference physics-list and an optimized parameters-list have been proposed. Satisfactory agreement against depth-dose profiles measurements was obtained. The simulation of transverse profiles using different Monte Carlo codes showed significant deviations. This point

  19. Time-resolved x-ray line emission studies of thermal transport in multiple beam uv-irradiated targets

    International Nuclear Information System (INIS)

    Jaanimagi, P.A.; Henke, B.L.; Delettrez, J.; Richardson, M.C.

    1984-01-01

    Thermal transport in spherical targets irradiated with multiple, nanosecond duration laser beams, has been a topic of much discussion recently. Different inferences on the level of thermal flux inhibition have been drawn from plasma velocity and x-ray spectroscopic diagnostics. We present new measurements of thermal transport on spherical targets made through time-resolved x-ray spectroscopic measurements of the progress of the ablation surface through thin layers of material on the surface of the target. These measurements, made with 6 and 12 uv (351 nm) nanosecond beams from OMEGA, will be compared to previous thermal transport measurements. Transparencies of the conference presentation are given

  20. Transport of laser accelerated proton beams and isochoric heating of matter

    International Nuclear Information System (INIS)

    Roth, M; Alber, I; Guenther, M; Harres, K; Bagnoud, V; Brown, C; Gregori, G; Clarke, R; Heathcote, R; Li, B; Daido, H; Fernandez, J; Flippo, K; Gaillard, S; Gauthier, C; Glenzer, S; Kritcher, A; Kugland, N; LePape, S; Makita, M

    2010-01-01

    The acceleration of intense proton and ion beams by ultra-intense lasers has matured to a point where applications in basic research and technology are being developed. Crucial for harvesting the unmatched beam parameters driven by the relativistic electron sheath is the precise control of the beam. We report on recent experiments using the PHELIX laser at GSI, the VULCAN laser at RAL and the TRIDENT laser at LANL to control and use laser accelerated proton beams for applications in high energy density research. We demonstrate efficient collimation of the proton beam using high field pulsed solenoid magnets, a prerequisite to capture and transport the beam for applications. Furthermore we report on two campaigns to use intense, short proton bunches to isochorically heat solid targets up to the warm dense matter state. The temporal profile of the proton beam allows for rapid heating of the target, much faster than the hydrodynamic response time thereby creating a strongly coupled plasma at solid density. The target parameters are then probed by X-ray Thomson scattering (XRTS) to reveal the density and temperature of the heated volume. This combination of two powerful techniques developed during the past few years allows for the generation and investigation of macroscopic samples of matter in states present in giant planets or the interior of the earth.