WorldWideScience

Sample records for neutral beam ions

  1. Ion-beam Plasma Neutralization Interaction Images

    Energy Technology Data Exchange (ETDEWEB)

    Igor D. Kaganovich; Edward Startsev; S. Klasky; Ronald C. Davidson

    2002-04-09

    Neutralization of the ion beam charge and current is an important scientific issue for many practical applications. The process of ion beam charge and current neutralization is complex because the excitation of nonlinear plasma waves may occur. Computer simulation images of plasma neutralization of the ion beam pulse are presented.

  2. Negative ion based neutral beams for plasma heating

    International Nuclear Information System (INIS)

    Prelec, K.

    1978-01-01

    Neutral beam systems based on negative ions have been considered because of a high expected power efficiency. Methods for the production, acceleration and neutralization of negative ions will be reviewed and possibilities for an application in neutral beam lines explored

  3. 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...

  4. Design of a negative ion neutral beam system for TNS

    International Nuclear Information System (INIS)

    Easoz, J.R.

    1978-05-01

    A conceptual design of a neutral beam line based on the neutralization of negative deuterium ions is presented. This work is a detailed design of a complete neutral beam line based on using negative ions from a direct extraction source. Anticipating major technological advancements, beam line components have been scaled including the negative ion sources and components for the direct energy recovery of charged beams and high speed cryogenic pumping. With application to the next step in experimental fusion reactors (TNS), the neutral beam injector system that has been designed provides 10 MW of 200 keV neutral deuterium atoms. Several arms are required for plasma ignition

  5. Prototype ion source for JT-60 neutral beam injectors

    International Nuclear Information System (INIS)

    Akiba, M.

    1981-01-01

    A prototype ion source for JT-60 neutral beam injectors has been fabricated and tested. Here, we review the construction of the prototype ion source and report the experimental results about the source characteristics that has been obtained at this time. The prototype ion source is now installed at the prototype unit of JT-60 neutral beam injection units and the demonstration of the performances of the ion source and the prototype unit has just started

  6. Ion accumulation and space charge neutralization in intensive electron beams for ion sources and electron cooling

    International Nuclear Information System (INIS)

    Shirkov, G.D.

    1996-01-01

    The Electron Beam Ion Sources (EBIS), Electron Beam Ion Traps (EBIT) and electron beams for electron cooling application have the beam parameters in the same ranges of magnitudes. EBIS and EBIT produce and accumulate ions in the beam due to electron impact ionization. The cooling electron beam accumulates positive ions from the residual gas in the accelerator chamber during the cooling cycle. The space charge neutralization of cooling beam is also used to reduce the electron energy spread and enhance the cooling ability. The advanced results of experimental investigations and theoretical models of the EBIS electron beams are applied to analyze the problem of beam neutralization in the electron cooling techniques. The report presents the analysis of the most important processes connected with ion production, accumulation and losses in the intensive electron beams of ion sources and electron cooling systems for proton and ion colliders. The inelastic and elastic collision processes of charged particles in the electron beams are considered. The inelastic processes such as ionization, charge exchange and recombination change the charge states of ions and neutral atoms in the beam. The elastic Coulomb collisions change the energy of particles and cause the energy redistribution among components in the electron-ion beams. The characteristic times and specific features of ionization, beam neutralization, ion heating and loss in the ion sources and electron cooling beams are determined. The dependence of negative potential in the beam cross section on neutralization factor is studied. 17 refs., 5 figs., 1 tab

  7. RF plasma source for heavy ion beam charge neutralization

    International Nuclear Information System (INIS)

    Efthimion, Philip C.; Gilson, Erik; Grisham, Larry; Davidson, Ronald C.; Yu, Simon S.; Logan, B. Grant

    2003-01-01

    Highly ionized plasmas are being used as a medium for charge neutralizing heavy ion beams in order to focus the ion beam to a small spot size. A radio frequency (RF) plasma source has been built at the Princeton Plasma Physics Laboratory (PPPL) in support of the joint Neutralized Transport Experiment (NTX) at the Lawrence Berkeley National Laboratory (LBNL) to study ion beam neutralization with plasma. The goal is to operate the source at pressures ∼ 10 -5 Torr at full ionization. The initial operation of the source has been at pressures of 10 -4 -10 -1 Torr and electron densities in the range of 10 8 -10 11 cm -3 . Recently, pulsed operation of the source has enabled operation at pressures in the 10 -6 Torr range with densities of 10 11 cm -3 . Near 100% ionization has been achieved. The source has been integrated with the NTX facility and experiments have begun

  8. Development of the ion source for PDX neutral beam injection

    International Nuclear Information System (INIS)

    Menon, M.M.; Tsai, C.C.; Gardner, W.L.; Barber, G.C.; Haselton, H.H.; Ponte, N.S.; Ryan, P.M.; Schechter, D.E.; Stirling, W.L.; Whealton, J.H.

    1979-01-01

    The paper describes the development of the ion source for neutral beam injection heating of PDX plasma. After a brief description of the plasma generator, the performance characteristics of the source, with different types of grids, are described. Based on test stand results it is concluded that at least two different versions of the source should be able to meet and even exceed the neutral power and energy requirements expected out of PDX injectors

  9. Ferroelectric Plasma Source for Heavy Ion Beam Charge Neutralization

    International Nuclear Information System (INIS)

    Efthimion, Philip C.; Gilson, Erik P.; Grisham, Larry; Davidson, Ronald C.; Yu, Simon; Waldron, William; Logan, B. Grant

    2005-01-01

    Plasmas are employed as a source of unbound electrons for charge neutralizing heavy ion beams to allow them to focus to a small spot size. Calculations suggest that plasma at a density of 1-100 times the ion beam density and at a length ∼ 0.1-1 m would be suitable. To produce one-meter plasma, large-volume plasma sources based upon ferroelectric ceramics are being developed. These sources have the advantage of being able to increase the length of the plasma and operate at low neutral pressures. The source utilizes the ferroelectric ceramic BaTiO 3 to form metal plasma. The drift tube inner surface of the Neutralized Drift Compression Experiment (NDCX) will be covered with ceramic, and high voltage (∼ 1-5 kV) applied between the drift tube and the front surface of the ceramic by placing a wire grid on the front surface. A prototype ferroelectric source 20 cm long has produced plasma densities of 5 x 10 11 cm -3 . The source was integrated into the previous Neutralized Transport Experiment (NTX), and successfully charge neutralized the K + ion beam. Presently, the one-meter source is being fabricated. The source is being characterized and will be integrated into NDCX for charge neutralization experiments

  10. Pierce instability in neutralized inertial confinement fusion ion beams

    International Nuclear Information System (INIS)

    Lemons, D.S.; Cary, J.R.

    1982-01-01

    The stability of a charge and current neutralized electron-ion beam propagating between two planar boundaries is investigated. For equipotential boundaries the beam is, as originally shown by Pierce, electrostatically unstable for electron current densities above a certain limiting value. If, however, the electric field at the upstream boundary is required to vanish, there is no instability. An intermediate case, in which the two boundaries are electrically connected with a finite conductivity plasma, corresponds to the proposed use of neutralized light and heavy ion beams for inertial confinement fusion drivers. Results indicate such beams can propagate either stably or with zero-frequency Pierce instability growth rates which are probably insignificant. lectric currents; boundary conditions; current density; electric fields; plasma;

  11. National negative-ion-based neutral-beam development plan

    International Nuclear Information System (INIS)

    Cooper, W.S.; Pyle, R.V.

    1983-08-01

    The plan covers facilities required, program milestones, and decision points. It includes identification of applications, experiments, theoretical research areas, development of specific technologies and reactor development and demonstration facilities required to bring about the successful application of negative-ion-based neutral beams. Particular emphasis is placed on those activities leading to use on existing plasma confinement experiments or their upgrades

  12. Negative-ion-based neutral beams for fusion

    International Nuclear Information System (INIS)

    Cooper, W.S.; Anderson, O.A.; Chan, C.F.

    1987-10-01

    To maximize the usefulness of an engineering test reactor (e.g., ITER, TIBER), it is highly desirable that it operate under steady-state conditions. The most attractive option for maintaining the circulating current needed in the center of the plasma is the injection of powerful beams of neutral deuterium atoms. The beam simultaneously heats the plasma. At the energies required, in excess of 500 keV, such beams can be made by accelerating D - ions and then removing the electron. Sources are being developed that generate the D - ions in the volume of a specially constructed plasma discharge, without the addition of cesium. These sources must operate with minimum gas flow, to avoid stripping the D - beam, and with minimum electron output. We are designing at LBL highly efficient electrostatic accelerators that combine electric strong-focusing with dc acceleration and offer the possibility of varying the beam energy at constant current while minimizing breakdown. Some form of rf acceleration may also be required. To minimize irradiation of the ion sources and accelerators, the D - beam can be transported through a maze in the neutron shielding. The D - ions can be converted to neutrals in a gas or plasma target, but advances in laser and mirror technology may make possible very efficient photodetachment systems by the time an ETR becomes operational. 9 refs., 4 figs

  13. 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

  14. Ferroelectric Plasma Source for Heavy Ion Beam Charge Neutralization

    CERN Document Server

    Efthimion, Philip; Gilson, Erik P; Grisham, Larry; Logan, B G; Waldron, William; Yu, Simon

    2005-01-01

    Plasmas are employed as a medium for charge neutralizing heavy ion beams to allow them to focus to a small spot size. Calculations suggest that plasma at a density of 1-100 times the ion beam density and at a length ~ 0.1-1 m would be suitable. To produce 1 meter plasma, large-volume plasma sources based upon ferroelectric ceramics are being considered. These sources have the advantage of being able to increase the length of the plasma and operate at low neutral pressures. The source will utilize the ferroelectric ceramic BaTiO3 to form metal plasma. The drift tube inner surface of the Neutralized Drift Compression Experiment (NDCX) will be covered with ceramic. High voltage (~ 1-5 kV) is applied between the drift tube and the front surface of the ceramic by placing a wire grid on the front surface. A prototype ferroelectric source 20 cm long produced plasma densities ~ 5x1011 cm-3. The source was integrated into the experiment and successfully charge neutralized the K ion beam. Presently, the 1 meter source ...

  15. Experiments on Ion Beam Space-Charge Neutralization with Pulsed Electron Beams

    CERN Document Server

    Herleb, U

    1998-01-01

    Space-charge neutralization of heavy ion beams with electron beam pulses generated by electron guns incorporating ferroelectric cathodes has been experimentally investigated. Several experiments are described, the results of which prove that the intensity of selected ion beam parts with defined charge states generated in a laser ion source can be increased by an order of magnitude. For elevated charge states the intensity amplification is more significant than for low charge states. A charge enhancement factor of four has been achieved by neutralization with pulsed electron beams for Al7+ ions generated from an aluminium target.

  16. Large area ion source for neutral beam injection

    International Nuclear Information System (INIS)

    Bottiglioni, F.; Bussac, J.P.; Desmons, M.; Fumelli, M.

    1983-01-01

    JET standard neutral beam injectors require an extraction area of 45 x 18 cm 2 . A plasma source suited to such a large dimension has been constructed and operated a few months on a test stand, prior to its mounting on the PINI now under test at FAR. This source is a rectangular Periplasmatron strongly cooled for 10 s pulses. So far, pulses of 2 s at 800 A and 110 V have been obtained. The nominal ion current density of 200 mA/cm 2 has been achieved, with an overall plasma uniformity better than +- 6%. (author)

  17. Investigation of accelerated neutral atom beams created from gas cluster ion beams

    Science.gov (United States)

    Kirkpatrick, A.; Kirkpatrick, S.; Walsh, M.; Chau, S.; Mack, M.; Harrison, S.; Svrluga, R.; Khoury, J.

    2013-07-01

    A new concept for ultra-shallow processing of surfaces known as accelerated neutral atom beam (ANAB) technique employs conversion of energetic gas cluster ions produced by the gas cluster ion beam (GCIB) method into intense collimated beams of coincident neutral gas atoms having controllable average energies from less than 10 eV per atom to beyond 100 eV per atom. A beam of accelerated gas cluster ions is first produced as is usual in GCIB, but conditions within the source ionizer and extraction regions are adjusted such that immediately after ionization and acceleration the clusters undergo collisions with non-ionized gas atoms. Energy transfer during these collisions causes the energetic cluster ions to release many of their constituent atoms. An electrostatic deflector is then used to eliminate charged species, leaving the released neutral atoms to still travel collectively at the same velocities they had as bonded components of their parent clusters. Upon target impact, the accelerated neutral atom beams produce effects similar to those normally associated with GCIB, but to shallower depths, with less surface damage and with superior subsurface interfaces. The paper discusses generation and characterization of the accelerated neutral atom beams, describes interactions of the beams with target surfaces, and presents examples of ongoing work on applications for biomedical devices.

  18. 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...

  19. Efficient production of neutral beams by photodetachment of negative ions

    International Nuclear Information System (INIS)

    Fink, J.H.; Hamilton, G.W.

    1977-01-01

    A neutral fraction approaching 97 percent can be attained by photodetachment of negative ions if the photon density and thickness are adequate. This high efficiency of neutralization is desirable not only because of the improvement in power balance and power efficiency but also because of the increase in the useable beam current per module. Only modest improvements in commercial solid-state lasers are required to fulfill the requirements of a photodetachment cell for a fusion reactor. The wavelength of 0.85 x 10 -4 cm is suitable with respect to the photodetachment cross section, the performance characteristics of present-day lasers, and the high reflectivity of the mirrors required for the optical cavity. Improvements may be possible by using resonances in the near ultraviolet region to enhance the photodetachment cross section. Three reactor-design studies were conducted and it was found that the required laser power is only economical for large injection systems in which beams of several hundred amperes are passed through a single optical cavity for photodetachment. The method is not economical for smaller systems

  20. Beam optics study of a negative ion source for neutral beam injection application at ASIPP

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Jiang-Long; Liang, Li-Zhen [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Jiang, Cai-Chao [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Graduate school, University of Science and Technology of China, Hefei 230026 (China); Xie, Ya-Hong, E-mail: xieyh@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Hu, Chun-Dong; Li, Jun; Gu, Yu-Ming; Chen, Yu-Qian [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Li, Jing-Yong; Wu, Ming-Shan [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Graduate school, University of Science and Technology of China, Hefei 230026 (China)

    2017-04-15

    In order to study the generation and extraction of negative ions for neutral beam injection application, a negative ion source is being designed and constructed at Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP). Through a four electrode grids system inside the accelerator, a negative ion beam will be extracted and accelerated up to −60 kV on a reduced scale extraction area of 12 × 50 cm{sup 2} (the area of PG apertures is 185 cm{sup 2}). The beam optics is a key issue for the accelerator design, and greatly determine the source experimental performance in term of beam current, heat load on the grid, beam divergence, and so on. In this paper, the trajectories of electrons and negative ions were simulated in the electrode grids of the negative ion source. The filter capability of electron deflection magnet on the co-extracted electrons is evaluated and confirmed. The negative ion beam optics was designed according to the calculated results of beam divergence and beam radius along the beamlet in different acceleration voltages. The deflection effect of the electron deflection magnet on the negative ion beam was investigated in the single beamlet case and multi-beamlets case.

  1. Negative hydrogen ion sources for neutral beam injectors

    International Nuclear Information System (INIS)

    Prelec, K.

    1977-01-01

    Negative ion sources offer an attractive alternative in the design of high energy neutral beam injectors. The requirements call for a single source unit capable of yielding H - or D - beam currents of up to 10 A, operating with pulses of 1 s duration or longer, with gas and power efficiencies comparable to or better than achievable with double electron capture systems. H - beam currents of up to 1 A have already been achieved in pulses of 10 ms; gas and power efficiencies were, however, lower than required. In order to increase the H - yield, extend the pulse length and improve gas and power efficiencies fundamental processes in the source plasma and on cesium covered electrode surfaces have to be analyzed; these processes will be briefly reviewed and scaling rules established. Based on these considerations as well as on results obtained with 1 A source models a larger model was designed and constructed, having a 7.5 cm long cathode with forced cooling. Results of initial tests will be presented and possible scaling up to 10 A units discussed

  2. Computational study of the first stage of hypersonic ion beam neutralization: The cross neutralization stage

    International Nuclear Information System (INIS)

    Pomot, C.; Dolique, J.M.

    1975-01-01

    A study is made of the first stage of evolution of a hypersonic ion beam in which thermoelectrons are emitted by a heated grid, known as the neutralizer. Downstream from the neutralizer there appears successively as a sheath a range of periodic and quasi-stationary electric field and a front where the electric field oscillates with the plasma frequency. The sheath is self-regulated. Some electrons are trapped in the periodic and stationary electric field. The characteristics of the periodic, quasi-stationary range correspond to those of both an experimental study and one-dimensional time-independent macroscopic theory. This quasi-stationary regime builds up in a time smaller than ω/subp/e -1 and is studied for a few periods ω/subP//sube/ -1 . The subsequent evolution of this state of nonequilibrium is not investigated. The experimental study has shown that, as for the neutralization of a subsonic ion beam, it leads to a field-free, homogeneous medium: a ''synthesized plasma.'' The importance of the first stage described herein, which may be called the gross neutralization stage, is due to the properties of mean neutrality in the current and in the charge insured by the regulating sheath, properties which will be preseved downstream

  3. Method of active charge and current neutralization of intense ion beams for ICF

    International Nuclear Information System (INIS)

    Guiragossian, Z.G.T.; Orthel, J.L.; Lemons, D.S.; Thode, L.E.

    1981-01-01

    Methods of generating the beam neutralization electrons with required properties are given in the context of a Light Ion Fusion Experiment (LIFE) designed accelerator. Recently derived envelope equations for neutralized and ballistically focused intense ion beams are applied to the LIFE geometry in which 10 MeV He + multiple beamlets coalesce and undergo 45:1 radial compression while beam pulses experience a 20:1 axial compression in the propagation range of 10 m. Both active and auto-neutralization methods are examined and found to produce initial electron temperatures consistent with the requirement of the envelope equation for both radial and axial adiabatic beam pulse compressions. The stability of neutralized beam propagation is also examined concerning the Pierce type electrostatic instability and for the case of LIFE beams it is found to have insignificant effect. A scaled experimental setup is presented which can serve to perform near term tests on the ballistically focused propagation of neutralized light ion beams

  4. Production of intense negative hydrogen beams with polarized nuclei by selective neutralization of cold negative ions

    Science.gov (United States)

    Hershcovitch, A.

    1984-02-13

    A process for selectively neutralizing H/sup -/ ions in a magnetic field to produce an intense negative hydrogen ion beam with spin polarized protons. Characteristic features of the process include providing a multi-ampere beam of H/sup -/ ions that are

  5. Generating high-efficiency neutral beams by using negative ions in an inductively coupled plasma source

    International Nuclear Information System (INIS)

    Samukawa, Seiji; Sakamoto, Keisuke; Ichiki, Katsunori

    2002-01-01

    To minimize radiation damage caused by charge buildup or ultraviolet and x-ray photons during etching, we developed a high-performance neutral-beam etching system. The neutral-beam source consists of an inductively coupled plasma (ICP) source and parallel top and bottom carbon plates. The bottom carbon plate has numerous apertures for extracting neutral beams from the plasma. When a direct current (dc) bias is applied to the top and bottom plates, the generated positive or negative ions are accelerated toward the bottom plate. Most of them are then efficiently converted into neutral atoms, either by neutralization in charge-transfer collisions with gas molecules during ion transport and with the aperture sidewalls in the bottom plate, or by recombination with low-energy electrons near the end of the bottom plate. We found that negative ions are more efficiently converted into neutral atoms than positive ions. The neutralization efficiency of negative ions was almost 100%, and the maximum neutral flux density was equivalent to 4.0 mA/cm2. A neutral beam can thus be efficiently produced from the ICP source and apertures in our new neutral-beam source

  6. Operation of TFTR neutral beams with heavy ions

    International Nuclear Information System (INIS)

    Kamperschroer, J.H.; Stevenson, T.N.; Wright, K.E.; Dudek, L.E.; Grisham, L.R.; Newman, R.A.; O'Connor, T.E.; Oldaker, M.E.; von Halle, A.; Williams, M.D.

    1991-07-01

    High Z neutral atoms have been injected into TFTR plasmas in an attempt to enhance plasma confinement through modification of the edge electric field. TFTR ion sources have extracted 9 A of 62 keV Ne + for up to 0.2 s during injection into deuterium plasmas, and for 0.5 s during conditioning pulses. Approximately 400 kW of Ne 0 have been injected from each of two ion sources. Operation was at full bending magnet current, with the Ne + barely contained on the ion dump. Beamline design modifications to permit operation up to 120 keV with krypton or xenon are described. Such ions are too massive to be deflected up to the ion dump. The plan, therefore, is to armor those components receiving these ions. Even with this armor, modest increases in the bending magnet current capability are necessary to safely reach 120 kV with Kr or Xe. Information relevant to heavy ion operation was also acquired when several ion sources were inadvertently operated with water contamination. Spectroscopic analysis of certain pathological pulses indicate that up to 6% of the extracted ions were water. After dissociation in the neutralizer, water yields oxygen ions which, as with Ne, Kr, and Xe, are under-deflected by the magnet. Damage to a calorimeter scraper, due to the focal properties of the magnet, has resulted. A magnified power density of 6 KW/cm 2 for 2 s, from ∼ 90 kW of O + , is the suspected cause. 11 refs., 4 figs

  7. Nonlinear Charge and Current Neutralization of an Ion Beam Pulse in a Pre-formed Plasma

    International Nuclear Information System (INIS)

    Kaganovich, Igor D.; Shvets, Gennady; Startsev, Edward; Davidson, Ronald C.

    2001-01-01

    The propagation of a high-current finite-length ion beam in a cold pre-formed plasma is investigated. The outcome of the calculation is the quantitative prediction of the degree of charge and current neutralization of the ion beam pulse by the background plasma. The electric magnetic fields generated by the ion beam are studied analytically for the nonlinear case where the plasma density is comparable in size with the beam density. Particle-in-cell simulations and fluid calculations of current and charge neutralization have been performed for parameters relevant to heavy ion fusion assuming long, dense beams with el >> V(subscript b)/omega(subscript b), where V(subscript b) is the beam velocity and omega subscript b is the electron plasma frequency evaluated with the ion beam density. An important conclusion is that for long, nonrelativistic ion beams, charge neutralization is, for all practical purposes, complete even for very tenuous background plasmas. As a result, the self-magnetic force dominates the electric force and the beam ions are always pinched during beam propagation in a background plasma

  8. Experiments on Ion Space-Charge Neutralization with Pulsed Electron Beams

    CERN Document Server

    Herleb, U

    1996-01-01

    The method of space-charge neutralization of heavy ion beams with electron beam pulses generated with electron guns incorporating ferroelectric cathodes has been experimentally investigated. Several experiments are described, the results of which prove that the intensity of selected ion beam parts with defined charge states generated in a laser ion source may be increased by one order of magnitude. For elevated charge states the intensity amplification is more significant than for low charge states. For $Al^(7+)$ ions from an aluminium target a charge enhancement by a factor of 4 has been achieved by electron beam focusing.

  9. Measurements of the fast ion distribution during neutral beam injection and ion cyclotron heating in ATF [Advanced Toroidal Facility

    International Nuclear Information System (INIS)

    Wade, M.R.; Kwon, M.; Thomas, C.E.; Colchin, R.J.; England, A.C.; Gossett, J.M.; Horton, L.D.; Isler, R.C.; Lyon, J.F.; Rasmussen, D.A.; Rayburn, T.M.; Shepard, T.D.; Bell, G.L.; Fowler, R.H.; Morris, R.N.

    1990-01-01

    A neutral particle analyzer (NPA) with horizontal and vertical scanning capability has been used to make initial measurements of the fast ion distribution during neutral beam injection (NBI) and ion cyclotron heating (ICH) on the Advanced Toroidal Facility (ATF). These measurements are presented and compared with the results of modeling codes that predict the analyzer signals during these heating processes. 6 refs., 5 figs

  10. Concepts for the magnetic design of the MITICA neutral beam test facility ion accelerator.

    Science.gov (United States)

    Chitarin, G; Agostinetti, P; Marconato, N; Marcuzzi, D; Sartori, E; Serianni, G; Sonato, P

    2012-02-01

    The megavolt ITER injector concept advancement neutral injector test facility will be constituted by a RF-driven negative ion source and by an electrostatic Accelerator, designed to produce a negative Ion with a specific energy up to 1 MeV. The beam is then neutralized in order to obtain a focused 17 MW neutral beam. The magnetic configuration inside the accelerator is of crucial importance for the achievement of a good beam efficiency, with the early deflection of the co-extracted and stripped electrons, and also of the required beam optic quality, with the correction of undesired ion beamlet deflections. Several alternative magnetic design concepts have been considered, comparing in detail the magnetic and beam optics simulation results, evidencing the advantages and drawbacks of each solution both from the physics and engineering point of view.

  11. Development of a negative ion-based neutral beam injector in Novosibirsk.

    Science.gov (United States)

    Ivanov, A A; Abdrashitov, G F; Anashin, V V; Belchenko, Yu I; Burdakov, A V; Davydenko, V I; Deichuli, P P; Dimov, G I; Dranichnikov, A N; Kapitonov, V A; Kolmogorov, V V; Kondakov, A A; Sanin, A L; Shikhovtsev, I V; Stupishin, N V; Sorokin, A V; Popov, S S; Tiunov, M A; Belov, V P; Gorbovsky, A I; Kobets, V V; Binderbauer, M; Putvinski, S; Smirnov, A; Sevier, L

    2014-02-01

    A 1000 keV, 5 MW, 1000 s neutral beam injector based on negative ions is being developed in the Budker Institute of Nuclear Physics, Novosibirsk in collaboration with Tri Alpha Energy, Inc. The innovative design of the injector features the spatially separated ion source and an electrostatic accelerator. Plasma or photon neutralizer and energy recuperation of the remaining ion species is employed in the injector to provide an overall energy efficiency of the system as high as 80%. A test stand for the beam acceleration is now under construction. A prototype of the negative ion beam source has been fabricated and installed at the test stand. The prototype ion source is designed to produce 120 keV, 1.5 A beam.

  12. Performance of a modified DuoPIGatron ion source for PLT neutral beam injectors

    International Nuclear Information System (INIS)

    Tsai, C.C.; Stirling, W.L.; Haselton, H.H.

    1978-09-01

    The performance of a modified duoPIGatron ion source for PLT neutral beam injectors is described. The 22-cm source has been operated to deliver beams of 70 A, up to 45 keV, and 0.5 sec. Following a brief review of source operation, the dominant reactions leading to an enhanced atomic ion fraction in the source plasma are emphasized. In addition to the high atomic ion species yield (about 85%), other important characteristics of the source such as high arc efficiency (about 1.1 A ion beam current per kW of arc power), long filament lifetime, high reliability, and scalability are also described

  13. Ion power balance in neutral beam heated discharges on the National Spherical Torus Experiment (NSTX)

    Science.gov (United States)

    Ross, Patrick William

    In this dissertation, ion power balance is studied in the National Spherical Torus Experiment (NSTX). In order to fully understand all the terms in the power balance equation, an experiment was conducted in which the input power of the NSTX discharges was modulated using the neutral beam input power. Individual neutral beam sources were turned on or off to increase or decrease the input power. The modulations were designed to create a localized perturbation in the fast ion phase space distribution. Measurements were taken with diagnostics on NSTX including the neutral particle analyzer (NPA), the NSTX Thomson scattering diagnostic (MPTS) and the charge exchange diagnostic (CHERS), which measure the ion and electron density and temperature. Reconstructions of the plasma equilibrium were made using the LRDFIT code and power balance was calculated using the TRANSP transport code. The TRANSP code inputs the electron and ion temperatures and densities, and calculates the various power balance terms. Excess ion heating is shown to exist for some neutral beam heated discharges on NSTX. When all three neutral beam sources are on, the total power outflow through the various loss terms exceeds the input power calculated through classical heating of the ions by the slowing down of the neutral beams. The excess heating is approximately 0.5 MW of power, which represents 8% of the total power put into the plasma from the neutral beams. This excess heating occurs at the same time as an increase in the amplitude of high frequency compressional Alfven eigenmodes (CAEs) with frequencies of 0.5--1.4 MHz. The CAE amplitudes coincide both temporally and spatially with the onset of the excess heating. The high-k microwave scattering diagnostic and magnetic pickup coils were used to estimate the amplitudes of these modes. Full orbit calculations were then performed using these modes, which demonstrate that thermal ions can be heated by the CAEs. The Edge Neutral Density Diagnostic (ENDD

  14. Neutral particle beam intensity controller

    Science.gov (United States)

    Dagenhart, W.K.

    1984-05-29

    The neutral beam intensity controller is based on selected magnetic defocusing of the ion beam prior to neutralization. The defocused portion of the beam is dumped onto a beam dump disposed perpendicular to the beam axis. Selective defocusing is accomplished by means of a magnetic field generator disposed about the neutralizer so that the field is transverse to the beam axis. The magnetic field intensity is varied to provide the selected partial beam defocusing of the ions prior to neutralization. The desired focused neutral beam portion passes along the beam path through a defining aperture in the beam dump, thereby controlling the desired fraction of neutral particles transmitted to a utilization device without altering the kinetic energy level of the desired neutral particle fraction. By proper selection of the magnetic field intensity, virtually zero through 100% intensity control of the neutral beam is achieved.

  15. Operating characteristics of a new ion source for KSTAR neutral beam injection system.

    Science.gov (United States)

    Kim, Tae-Seong; Jeong, Seung Ho; Chang, Doo-Hee; Lee, Kwang Won; In, Sang-Ryul

    2014-02-01

    A new positive ion source for the Korea Superconducting Tokamak Advanced Research neutral beam injection (KSTAR NBI-1) system was designed, fabricated, and assembled in 2011. The characteristics of the arc discharge and beam extraction were investigated using hydrogen and helium gas to find the optimum operating parameters of the arc power, filament voltage, gas pressure, extracting voltage, accelerating voltage, and decelerating voltage at the neutral beam test stand at the Korea Atomic Energy Research Institute in 2012. Based on the optimum operating condition, the new ion source was then conditioned, and performance tests were primarily finished. The accelerator system with enlarged apertures can extract a maximum 65 A ion beam with a beam energy of 100 keV. The arc efficiency and optimum beam perveance, at which the beam divergence is at a minimum, are estimated to be 1.0 A/kW and 2.5 uP, respectively. The beam extraction tests show that the design goal of delivering a 2 MW deuterium neutral beam into the KSTAR Tokamak plasma is achievable.

  16. Linear induction accelerator for charge-neutralized ion beams in inertial confinement fusion

    International Nuclear Information System (INIS)

    Batishchev, O.V.; Golota, V.I.; Karas, V.I.; Kiyashko, V.A.; Kornilov, E.A.; Sigov, Yu.S.; Silaev, I.I.; Fainberg, Ya.B.

    1993-01-01

    Results are presented from experimental, analytical, and numerical studies of the physical processes that occur in a high-current ion induction accelerator (the ion linac IINDUS). The experiments were performed in a module of the IINDUS accelerator consisting of an injector of gaseous or metallic ions and two induction sections with magnetically insulated cusps in the accelerator gaps filled with plasma. The following ion beam parameters were found: 2-3 kA, 0.5 MeV, 0.5 μs. The two most dangerous instabilities effecting beam quality were studied. These are the high-frequency beam-plasma instability and the filamentation instability. A nonlinear analytical theory of charge neutralization of a high-current ion beam in magnetically insulated accelerating gaps is presented. In order to develop diagnostics for high-current beams of accelerated particles the amplitude and shape of the acoustic pulse excited in a metal target by the particles have been studied theoretically and experimentally as functions of the beam parameters. The possibility of practical application of this acceleration in ICF has been studied using a 2.5-dimensional relativistic electromagnetic code to simulate the processes of acceleration, charge neutralization, and stability of the ion beam in the accelerating channel. The results provide evidence in favor of the prospects for this direction of research. 70 refs., 13 figs

  17. Beam divergence scaling in neutral beam injectors

    International Nuclear Information System (INIS)

    Holmes, A.J.T.

    1976-01-01

    One of the main considerations in the design of neutral beam injectors is to monimize the divergence of the primary ion beam and hence maximize the beam transport and minimize the input of thermal gas. Experimental measurements of the divergence of a cylindrical ion beam are presented and these measurements are used to analyze the major components of ion beam divergence, namely: space charge expansion, gas-ion scattering, emittance and optical aberrations. The implication of these divergence components in the design of a neutral beam injector system is discussed and a method of maximizing the beam current is described for a given area of source plasma

  18. Physics of neutralization of intense high-energy ion beam pulses by electrons

    International Nuclear Information System (INIS)

    Kaganovich, I. D.; Davidson, R. C.; Dorf, M. A.; Startsev, E. A.; Sefkow, A. B.; Lee, E. P.; Friedman, A.

    2010-01-01

    Neutralization and focusing of intense charged particle beam pulses by electrons form the basis for a wide range of applications to high energy accelerators and colliders, heavy ion fusion, and astrophysics. For example, for ballistic propagation of intense ion beam pulses, background plasma can be used to effectively neutralize the beam charge and current, so that the self-electric and self-magnetic fields do not affect the ballistic propagation of the beam. From the practical perspective of designing advanced plasma sources for beam neutralization, a robust theory should be able to predict the self-electric and self-magnetic fields during beam propagation through the background plasma. The major scaling relations for the self-electric and self-magnetic fields of intense ion charge bunches propagating through background plasma have been determined taking into account the effects of transients during beam entry into the plasma, the excitation of collective plasma waves, the effects of gas ionization, finite electron temperature, and applied solenoidal and dipole magnetic fields. Accounting for plasma production by gas ionization yields a larger self-magnetic field of the ion beam compared to the case without ionization, and a wake of current density and self-magnetic field perturbations is generated behind the beam pulse. A solenoidal magnetic field can be applied for controlling the beam propagation. Making use of theoretical models and advanced numerical simulations, it is shown that even a small applied magnetic field of about 100 G can strongly affect the beam neutralization. It has also been demonstrated that in the presence of an applied magnetic field the ion beam pulse can excite large-amplitude whistler waves, thereby producing a complex structure of self-electric and self-magnetic fields. The presence of an applied solenoidal magnetic field may also cause a strong enhancement of the radial self-electric field of the beam pulse propagating through the

  19. Physics of Neutralization of Intense High-Energy Ion Beam Pulses by Electrons

    International Nuclear Information System (INIS)

    Kaganovich, I.D.; Davidson, R.C.; Dorf, M.A.; Startsev, E.A.; Sefkow, A.B.; Lee, E.P.; Friedman, A.

    2010-01-01

    Neutralization and focusing of intense charged particle beam pulses by electrons forms the basis for a wide range of applications to high energy accelerators and colliders, heavy ion fusion, and astrophysics. For example, for ballistic propagation of intense ion beam pulses, background plasma can be used to effectively neutralize the beam charge and current, so that the self-electric and self- magnetic fields do not affect the ballistic propagation of the beam. From the practical perspective of designing advanced plasma sources for beam neutralization, a robust theory should be able to predict the self-electric and self-magnetic fields during beam propagation through the background plasma. The major scaling relations for the self-electric and self-magnetic fields of intense ion charge bunches propagating through background plasma have been determined taking into account the effects of transients during beam entry into the plasma, the excitation of collective plasma waves, the effects of gas ionization, finite electron temperature, and applied solenoidal and dipole magnetic fields. Accounting for plasma production by gas ionization yields a larger self-magnetic field of the ion beam compared to the case without ionization, and a wake of current density and self-magnetic field perturbations is generated behind the beam pulse. A solenoidal magnetic field can be applied for controlling the beam propagation. Making use of theoretical models and advanced numerical simulations, it is shown that even a small applied magnetic field of about 100G can strongly affect the beam neutralization. It has also been demonstrated that in the presence of an applied magnetic field the ion beam pulse can excite large-amplitude whistler waves, thereby producing a complex structure of self-electric and self-magnetic fields. The presence of an applied solenoidal magnetic field may also cause a strong enhancement of the radial self-electric field of the beam pulse propagating through the

  20. Fast-scan monitor examines neutral-beam ion-density profile

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    All of the magnetic mirror confinement fusion experiments at LLL and at other laboratories depend on pulsed, energetic neutral-beam injection for fueling and imparting energy to the trapped plasma for density build-up and stability studies. It is vital to be able to monitor how well the injected ion beam is aimed and focused. To do this, we have designed an ion-beam current-density profile monitor that uses a commercial minimodular data acquisition system. Our prototype model monitors a single 20-kV, 50-A, 10-ms beam. However, the method is applicable to any number of beams with similar sampling target arrays. Also, the electronics can be switched to monitor any one of several target collectors

  1. Transport investigations during neutral-beam injection, ion cyclotron heating and pellet injection experiments on TFR

    International Nuclear Information System (INIS)

    1985-01-01

    Neutral-beam injection and ion cyclotron frequency heating experiments have been carried out successively on TFR with inconel and carbon limiters. Heating efficiencies are for both methods lower with carbon limiters than with inconel. In the case of neutral-beam injection, the ion temperature saturation is supposed to be due to fast-ion charge-exchange losses. The electron temperature saturation is, in the two cases, correlated with small-scale density fluctuation enhancement. The difficulty of deeply modifying the electron temperature profile is also observed during pellet injection. These observations suggest that even slight modifications of the electron temperature gradients lead to enhanced transport. The role of plasma/wall interaction and recycling has not been clarified, but could be important, in particular with carbon limiters. (author)

  2. DISSOLVED OXYGEN REDUCTION IN THE DIII-D NEUTRAL BEAM ION SOURCE COOLING SYSTEM

    International Nuclear Information System (INIS)

    YIP, H.; BUSATH, J.; HARRISON, S.

    2004-03-01

    OAK-B135 Neutral beam ion sources (NBIS) are critical components for the neutral beam injection system supporting the DIII-D tokamak. The NBIS must be cooled with 3028 (ell)/m (800 gpm) of de-ionized and de-oxygenated water to protect the sources from overheating and failure. These ions sources are currently irreplaceable. Since the water cooled molybdenum components will oxidize in water almost instantaneously in the presence of dissolved oxygen (DO), de-oxygenation is extremely important in the NBIS water system. Under normal beam operation the DO level is kept below 5 ppb. However, during weeknights and weekends when neutral beam is not in operation, the average DO level is maintained below 10 ppb by periodic circulation with a 74.6 kW (100 hp) pump, which consumes significant power. Experimental data indicated evidence of continuous oxygen diffusion through non-metallic hoses in the proximity of the NBIS. Because of the intermittent flow of the cooling water, the DO concentration at the ion source(s) could be even higher than measured downstream, and hence the concern of significant localized oxidation/corrosion. A new 3.73 kW (5 hp) auxiliary system, installed in the summer of 2003, is designed to significantly reduce the peak and the time-average DO levels in the water system and to consume only a fraction of the power

  3. Status of the Negative Ion Based Heating and Diagnostic Neutral Beams for ITER

    Science.gov (United States)

    Schunke, B.; Bora, D.; Hemsworth, R.; Tanga, A.

    2009-03-01

    The current baseline of ITER foresees 2 Heating Neutral Beam (HNB's) systems based on negative ion technology, each accelerating to 1 MeV 40 A of D- and capable of delivering 16.5 MW of D0 to the ITER plasma, with a 3rd HNB injector foreseen as an upgrade option [1]. In addition a dedicated Diagnostic Neutral Beam (DNB) accelerating 60 A of H- to 100 keV will inject ≈15 A equivalent of H0 for charge exchange recombination spectroscopy and other diagnostics. Recently the RF driven negative ion source developed by IPP Garching has replaced the filamented ion source as the reference ITER design. The RF source developed at IPP, which is approximately a quarter scale of the source needed for ITER, is expected to have reduced caesium consumption compared to the filamented arc driven ion source. The RF driven source has demonstrated adequate accelerated D- and H- current densities as well as long-pulse operation [2, 3]. It is foreseen that the HNB's and the DNB will use the same negative ion source. Experiments with a half ITER-size ion source are on-going at IPP and the operation of a full-scale ion source will be demonstrated, at full power and pulse length, in the dedicated Ion Source Test Bed (ISTF), which will be part of the Neutral Beam Test Facility (NBTF), in Padua, Italy. This facility will carry out the necessary R&D for the HNB's for ITER and demonstrate operation of the full-scale HNB beamline. An overview of the current status of the neutral beam (NB) systems and the chosen configuration will be given and the ongoing integration effort into the ITER plant will be highlighted. It will be demonstrated how installation and maintenance logistics have influenced the design, notably the top access scheme facilitating access for maintenance and installation. The impact of the ITER Design Review and recent design change requests (DCRs) will be briefly discussed, including start-up and commissioning issues. The low current hydrogen phase now envisaged for start

  4. Status of the Negative Ion Based Heating and Diagnostic Neutral Beams for ITER

    International Nuclear Information System (INIS)

    Schunke, B.; Bora, D.; Hemsworth, R.; Tanga, A.

    2009-01-01

    The current baseline of ITER foresees 2 Heating Neutral Beam (HNB's) systems based on negative ion technology, each accelerating to 1 MeV 40 A of D - and capable of delivering 16.5 MW of D 0 to the ITER plasma, with a 3rd HNB injector foreseen as an upgrade option. In addition a dedicated Diagnostic Neutral Beam (DNB) accelerating 60 A of H - to 100 keV will inject ≅15 A equivalent of H 0 for charge exchange recombination spectroscopy and other diagnostics. Recently the RF driven negative ion source developed by IPP Garching has replaced the filamented ion source as the reference ITER design. The RF source developed at IPP, which is approximately a quarter scale of the source needed for ITER, is expected to have reduced caesium consumption compared to the filamented arc driven ion source. The RF driven source has demonstrated adequate accelerated D - and H - current densities as well as long-pulse operation. It is foreseen that the HNB's and the DNB will use the same negative ion source. Experiments with a half ITER-size ion source are on-going at IPP and the operation of a full-scale ion source will be demonstrated, at full power and pulse length, in the dedicated Ion Source Test Bed (ISTF), which will be part of the Neutral Beam Test Facility (NBTF), in Padua, Italy. This facility will carry out the necessary R and D for the HNB's for ITER and demonstrate operation of the full-scale HNB beamline. An overview of the current status of the neutral beam (NB) systems and the chosen configuration will be given and the ongoing integration effort into the ITER plant will be highlighted. It will be demonstrated how installation and maintenance logistics have influenced the design, notably the top access scheme facilitating access for maintenance and installation. The impact of the ITER Design Review and recent design change requests (DCRs) will be briefly discussed, including start-up and commissioning issues. The low current hydrogen phase now envisaged for start

  5. Neutron spectroscopy measurements and modeling of neutral beam heating fast ion dynamics

    International Nuclear Information System (INIS)

    Hellesen, C; Sunden, E Andersson; Conroy, S; Ericsson, G; Johnson, M Gatu; Hjalmarsson, A; Kaellne, J; Ronchi, E; Sjoestrand, H; Weiszflog, M; Albergante, M; Ballabio, L; Gorini, G; Tardocchi, M; Giacomelli, L; Jenkins, I; Voitsekhovitch, I

    2010-01-01

    The energy spectrum of the neutron emission from beam-target reactions in fusion plasmas at the Joint European Torus (JET) has been investigated. Different beam energies as well as injection angles were used. Both measurements and simulations of the energy spectrum were done. The measurements were made with the time-of-flight spectrometer TOFOR. Simulations of the neutron spectrum were based on first-principle calculations of neutral beam deposition profiles and the fast ion slowing down in the plasma using the code NUBEAM, which is a module of the TRANSP package. The shape of the neutron energy spectrum was seen to vary significantly depending on the energy of the beams as well as the injection angle and the deposition profile in the plasma. Cross validations of the measured and modeled neutron energy spectra were made, showing a good agreement for all investigated scenarios.

  6. Mechanical properties considerations for use of epoxy insulators and bonded joints in neutral beam ion sources

    Science.gov (United States)

    Doll, D. W.; Trester, P. W.; Staley, H. G.

    1981-10-01

    In the Doublet III (D-III) neutral beam injectors, cast, rigid epoxy insulators are joined to the AISI 304 stainless steel corona rings with semirigid epoxy adhesive. Selected mechanical properties of these materials were measured between 11 C and 65 C, well below the material temperature limits, to identify the trends and to confirm adequate mechanical strength for the insulators. Significant creep deformation was measured at 22 C. Empirical relationships were developed to predict long term strain over a range of stress and temperature of design interest. Delayed failure was observed in bonded specimens at stress levels well below the ultimate strength. In order to protect the D-III neutral beam ion source epoxy from elevated temperature effects, a chill was installed in the cooling water circuit. Outgassing measurements of the insulator epoxy were made and found to be low and primarily H2O.

  7. PULSELAC program: space charge neutralized ion beams for inertial fusion applications

    International Nuclear Information System (INIS)

    Hamphries, S.; Anderson, R.; Freeman, J.; Lockner, T.; Poukey, J.; Ramirez, J.

    1982-01-01

    A linear induction accelerator PULSELAC-C constructed in Sandy Laboratories (USA) according to the program of intense ion beam application for thermonuclear fision initiation is described. The PULSELAC-C facility is intended to accelerate ions from N + to Ar + up to 4 Met at a beam current of 5 kA and pulse duration of 50 ns. The concept of induction acceleration and self-neutralization of the ion space charge by low-energy ele-- ctrons at magnetic isolation of accelerating gaps is used in the PULSELAC-C. The ion acceleration is planned to be performed in 16 aceelerating gaps each of them being designed for a 250 kV voltage at a pulse duration of 50 ns A large number of preliminary experiments on acceleration in such gaps have been conducted. A beam of 600 keV carbon ions with a 3 kA curpent and a divergence equal to 0.01 rad is obtained in the injector-5 gaps system

  8. The development of the radio frequency driven negative ion source for neutral beam injectors (invited).

    Science.gov (United States)

    Kraus, W; Fantz, U; Franzen, P; Fröschle, M; Heinemann, B; Riedl, R; Wünderlich, D

    2012-02-01

    Large and powerful negative hydrogen ion sources are required for the neutral beam injection (NBI) systems of future fusion devices. Simplicity and maintenance-free operation favors RF sources, which are developed intensively at the Max-Planck-Institut für Plasmaphysik (IPP) since many years. The negative hydrogen ions are generated by caesium-enhanced surface conversion of atoms and positive ions on the plasma grid surface. With a small scale prototype the required high ion current density and the low fraction of co-extracted electrons at low pressure as well as stable pulses up to 1 h could be demonstrated. The modular design allows extension to large source dimensions. This has led to the decision to choose RF sources for the NBI of the international fusion reactor, ITER. As an intermediate step towards the full size ITER source at IPP, the development will be continued with a half-size source on the new ELISE testbed. This will enable to gain experience for the first time with negative hydrogen ion beams from RF sources of these dimensions.

  9. Designing Neutralized Drift Compression for Focusing of Intense Ion Beam Pulses in a Background Plasma

    International Nuclear Information System (INIS)

    Kaganovich, I.D.; Davidson, R.C.; Dorf, M.; Startsev, E.A.; Barnard, J.J.; Friedman, A.; Lee, E.P.; Lidia, S.M.; Logan, B.G.; Roy, P.K.; Seidl, P.A.; Welch, D.R.; Sefkow, A.B.

    2009-01-01

    Neutralized drift compression offers an effective method for particle beam focusing and current amplification. In neutralized drift compression, a linear radial and longitudinal velocity drift is applied to a beam pulse, so that the beam pulse compresses as it drifts in the drift-compression section. The beam intensity can increase more than a factor of 100 in both the radial and longitudinal directions, resulting in more than 10,000 times increase in the beam number density during this process. The self-electric and self-magnetic fields can prevent tight ballistic focusing and have to be neutralized by supplying neutralizing electrons. This paper presents a survey of the present theoretical understanding of the drift compression process and plasma neutralization of intense particle beams. The optimal configuration of focusing and neutralizing elements is discussed in this paper.

  10. Characteristics of a long-pulse (30-s), high-power (4-MW) ion source for neutral beam injection

    International Nuclear Information System (INIS)

    Menon, M.M.; Barber, G.C.; Combs, S.K.

    1983-01-01

    A quasi-steady-state ion source has been developed for neutral beam injection applications. It is of the duoPIGatron type designed for delivering 50 A of hydrogen ions at 80 keV for 30-s-long pulses. Ion beams of 40 A at 75 keV were extracted for pulse lengths up to 30 s, maintaining excellent optical quality in the beam for the entire pulse duration. The design features and operational characteristics of the ion source are elaborated

  11. Design considerations for a negative ion source for dc operation of high-power, multi-megaelectron-volt neutral beams

    International Nuclear Information System (INIS)

    Tsai, C.C.; Stirling, W.L.; Akerman, M.A.; Becraft, W.R.; Dagenhart, W.K.; Haselton, H.H.; Ryan, P.M.; Schechter, D.E.; Whealton, J.H.

    1988-03-01

    A dc negative hydrogen and/or deuterium ion source is needed to prouce high-power, high-energy neutral beams for alpha diagnostics and current drive applicatiosn in fusion devices. The favorable beam particle energy for such applications extends to 1.5 MeV/amu. Continuous-wave (cw) radio-frequency quadrupole (RFQ) accelerators have been proposed to accelerate negative ions effeciently to this energy range. In this paper, the desired beam properties for ion beams injected into cw RFQ accelerators are summariezed. A number of candidate ion sources being developed at Culham, JAERI, LBL, and ORNL may prove useful for these applications. The properties of the Volume Ionization with Transverse Extraction (VITEX) ion sources being developed at ORNL are presented. Scaling such a dc ion source to produce ampere beams is discussed. 53 refs., 4 figs., 2 tabs

  12. Enhanced collective focusing of intense neutralized ion beam pulses in the presence of weak solenoidal magnetic fields

    International Nuclear Information System (INIS)

    Dorf, Mikhail A.; Davidson, Ronald C.; Kaganovich, Igor D.; Startsev, Edward A.

    2012-01-01

    The design of ion drivers for warm dense matter and high energy density physics applications and heavy ion fusion involves transverse focusing and longitudinal compression of intense ion beams to a small spot size on the target. To facilitate the process, the compression occurs in a long drift section filled with a dense background plasma, which neutralizes the intense beam self-fields. Typically, the ion bunch charge is better neutralized than its current, and as a result a net self-pinching (magnetic) force is produced. The self-pinching effect is of particular practical importance, and is used in various ion driver designs in order to control the transverse beam envelope. In the present work we demonstrate that this radial self-focusing force can be significantly enhanced if a weak (B ∼ 100 G) solenoidal magnetic field is applied inside the neutralized drift section, thus allowing for substantially improved transport. It is shown that in contrast to magnetic self-pinching, the enhanced collective self-focusing has a radial electric field component and occurs as a result of the overcompensation of the beam charge by plasma electrons, whereas the beam current becomes well-neutralized. As the beam leaves the neutralizing drift section, additional transverse focusing can be applied. For instance, in the neutralized drift compression experiments (NDCX) a strong (several Tesla) final focus solenoid is used for this purpose. In the present analysis we propose that the tight final focus in the NDCX experiments may possibly be achieved by using a much weaker (few hundred Gauss) magnetic lens, provided the ion beam carries an equal amount of co-moving neutralizing electrons from the preceding drift section into the lens. In this case the enhanced focusing is provided by the collective electron dynamics strongly affected by a weak applied magnetic field.

  13. Generation of intense polarized beams by selective neutralization of negative ions

    International Nuclear Information System (INIS)

    Hershcovitch, A.I.; Hinds, E.A.

    1983-01-01

    A novel scheme is proposed. This method is based on selective neutralization by laser negative hydrogen ions in a magnetic field. This selectivity is based on the fact that the final state of the neutralized atom depends on nuclear polarization in the magnetic field. A two-scenario approach is to be followed: one in which the resulting neutral atom is in the ground state, and in the other the neutral atom is in the n = 2 level. Limiting factors are discussed. The main advantages of this scheme are the availability of multi-ampere negative ion sources and the possibility to neutralize negative ions with very high efficiency. 15 references, 2 figures

  14. Power deposition by neutral beam injected fast ions in field-reversed configurations

    International Nuclear Information System (INIS)

    Takahashi, Toshiki; Kato, Takayuki; Kondoh, Yoshiomi; Iwasawa, Naotaka

    2004-01-01

    The effects of Coulomb collisions on neutral beam (NB) injected fast ions into field-reversed configuration (FRC) plasmas are investigated by calculating the single particle orbits, where the ions are subject to the slowing-down and pitch-angle collisions. The Monte Carlo method is used for the pitch-angle scattering, and the friction term is added to the equation of motion to show the effects of the slowing-down collision, such as the deposited power profile. The calculation parameters used are relevant to the NB injection on the FRC injection experiment device [T. Asai, Y. Suzuki, T. Yoneda, F. Kodera, M. Okubo, and S. Goto, Phys. Plasmas 7, 2294 (2000)]. It is found that the dominant local power deposition occurs in the open field region between the X point and the mirror point because of a concentration of fast ions and a longer duration travel at the mirror reflection point. In the present calculation, the maximum deposited power to the FRC plasma is about 10% of the injected power. Although the pitch-angle scattering by Coulomb collision destroys the mirror confinement of NB injected fast ions, this effect is found to be negligible. The loss mechanism due to nonadiabatic fast ion motion, which is intrinsic in nonuniform FRC plasmas, has a much greater effect than the pitch-angle scattering by Coulomb collision

  15. Efficiencies of gas neutralizers for multi-MeV beams of light negative ions

    International Nuclear Information System (INIS)

    Grisham, L.R.; Post, D.E.; Johnson, B.M.; Jones, K.W.; Barrette, J.; Kruse, T.H.; Tserruya, I.; Da-Hai, W.

    1982-01-01

    We report measurements of the neutral and charged particle fractions produced by running beams of Li - , C - , O - , and Si - at energies up to 7 MeV through gas cells of N 2 , Ar, or CO 2 . We discuss the implications of these measurements for the design of neutralizers to produce high-energy light atom beams for heating or current drive in tokamaks

  16. On the meniscus formation and the negative hydrogen ion extraction from ITER neutral beam injection relevant ion source

    Science.gov (United States)

    Mochalskyy, S.; Wünderlich, D.; Ruf, B.; Fantz, U.; Franzen, P.; Minea, T.

    2014-10-01

    The development of a large area (Asource,ITER = 0.9 × 2 m2) hydrogen negative ion (NI) source constitutes a crucial step in construction of the neutral beam injectors of the international fusion reactor ITER. To understand the plasma behaviour in the boundary layer close to the extraction system the 3D PIC MCC code ONIX is exploited. Direct cross checked analysis of the simulation and experimental results from the ITER-relevant BATMAN source testbed with a smaller area (Asource,BATMAN ≈ 0.32 × 0.59 m2) has been conducted for a low perveance beam, but for a full set of plasma parameters available. ONIX has been partially benchmarked by comparison to the results obtained using the commercial particle tracing code for positive ion extraction KOBRA3D. Very good agreement has been found in terms of meniscus position and its shape for simulations of different plasma densities. The influence of the initial plasma composition on the final meniscus structure was then investigated for NIs. As expected from the Child-Langmuir law, the results show that not only does the extraction potential play a crucial role on the meniscus formation, but also the initial plasma density and its electronegativity. For the given parameters, the calculated meniscus locates a few mm downstream of the plasma grid aperture provoking a direct NI extraction. Most of the surface produced NIs do not reach the plasma bulk, but move directly towards the extraction grid guided by the extraction field. Even for artificially increased electronegativity of the bulk plasma the extracted NI current from this region is low. This observation indicates a high relevance of the direct NI extraction. These calculations show that the extracted NI current from the bulk region is low even if a complete ion-ion plasma is assumed, meaning that direct extraction from surface produced ions should be present in order to obtain sufficiently high extracted NI current density. The calculated extracted currents, both ions

  17. Beam heating of the neutralizer gas of neutral beam injectors

    International Nuclear Information System (INIS)

    Ott, W.

    1989-02-01

    It was shown by Pamela that the target thickness of the neutralizer gas in neutral beam injectors is smaller than to be expected from gas flow calculations. He explained his findings by direct and indirect beam heating of the gas and a consequent flow acceleration. The role of the neutralizer plasma electrons in the gas heating scenario is reconsidered here. To this end the particle and energy balances of the electrons are solved with allowance for ionization and dissociation of the gas by the electrons. It is shown that the direct contribution of the electrons to heating is not dominant. Their indirect contribution via ion acceleration in the space charge sheath in front of the walls is usually stronger. Methods to increase the neutralizer target thickness are investigated. They are essentially (1) structuring the neutralizer surface in order to reduce the reflection of medium energy particles and to increase the gas accommodation, (2) cooling down the neutralizer to LN 2 -temperature. The scaling of the target thickness with various parameters is investigated and compared with 'cold' flow. Initially it was assumed that the neutralizer plasma electrons are hot and able to excite Balmer alpha radiation in collisions with H 2 molecules. The investigation shows that the electrons must be cold instead (T e + 2 and H + 3 ions leading to excited hydrogen atoms. (orig.)

  18. Manufacturing of the full size prototype of the ion source for the ITER neutral beam injector – The SPIDER beam source

    Energy Technology Data Exchange (ETDEWEB)

    Pavei, Mauro, E-mail: mauro.pavei@igi.cnr.it [Consorzio RFX, C.so Stati Uniti 4, I-35127, Padova (Italy); Boilson, Deirdre [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex (France); Bonicelli, Tullio [Fusion for Energy, C/Joseph Pla 2, 08019 Barcelona (Spain); Boury, Jacques [Thales Electron Devices, Velizy Villacoublay (France); Bush, Michael [Galvano-T GmbH, T, Raiffeisenstraße 8, 51570 Windeck (Germany); Ceracchi, Andrea; Faso, Diego [CECOM S.r.l., Via Tiburtina – Guidonia Montecelio, Roma (Italy); Graceffa, Joseph [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex (France); Heinemann, Bernd [Max-Planck-Institut für Plasmaphysik, D-85740 Garching (Germany); Hemsworth, Ronald [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex (France); Lievin, Christophe [Thales Electron Devices, Velizy Villacoublay (France); Marcuzzi, Diego [Consorzio RFX, C.so Stati Uniti 4, I-35127, Padova (Italy); Masiello, Antonio [Fusion for Energy, C/Joseph Pla 2, 08019 Barcelona (Spain); Sczepaniak, Bernd [Galvano-T GmbH, T, Raiffeisenstraße 8, 51570 Windeck (Germany); Singh, Mahendrajit [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex (France); Toigo, Vanni; Zaccaria, Pierluigi [Consorzio RFX, C.so Stati Uniti 4, I-35127, Padova (Italy)

    2015-10-15

    Highlights: • Negative ion sources are key components of neutral beam injectors for nuclear fusion. • The SPIDER experiment aims to optimize the negative ion source of MITICA and HNB. • The SPIDER Beam Source manufacturing is currently on-going. • Manufacturing and assembling technological issues encountered are presented. - Abstract: In ITER, each heating neutral beam injector (HNB) will deliver about 16.5 MW heating power by accelerating a 40 A deuterium negative ion beam up to the energy of 1 MeV. The ions are generated inside a caesiated negative ion source, where the injected H{sub 2}/D{sub 2} is ionized by a radio frequency electromagnetic field. The SPIDER test bed, currently being manufactured, is going to be the ion source test facility for the full size ion source of the HNBs and of the diagnostic neutral beam injector of ITER. The SPIDER beam source comprises an ion source with 8 radio-frequency drivers and a three-grid system, providing an overall acceleration up to energies of about 100 keV [1]. SPIDER represents a substantial step forward between the half ITER size ion source, which is currently being tested at the ELISE test bed in IPP-Garching, and the negative ion sources to be used on ITER, in terms of layout, dimensions and operating parameters. The SPIDER beam source will be housed inside a vacuum vessel which will be equipped with a beam dump and a graphite diagnostic calorimeter. The manufacturing design of the main parts of the SPIDER beam source has been completed and many of the tests on the prototypes have been successfully passed. The most complex parts, from the manufacturing point of view, of the ion source and the accelerator, developed by galvanic deposition of copper are being manufactured. The manufacturing phase will be completed within 2015, when the assembly of the device will start at the PRIMA site, in Padova (I). The paper describes the status of the procurement, the adaptations operated on the design of the beam

  19. ITER Neutral Beam Injection System

    International Nuclear Information System (INIS)

    Ohara, Yoshihiro; Tanaka, Shigeru; Akiba, Masato

    1991-03-01

    A Japanese design proposal of the ITER Neutral Beam Injection System (NBS) which is consistent with the ITER common design requirements is described. The injection system is required to deliver a neutral deuterium beam of 75MW at 1.3MeV to the reactor plasma and utilized not only for plasma heating but also for current drive and current profile control. The injection system is composed of 9 modules, each of which is designed so as to inject a 1.3MeV, 10MW neutral beam. The most important point in the design is that the injection system is based on the utilization of a cesium-seeded volume negative ion source which can produce an intense negative ion beam with high current density at a low source operating pressure. The design value of the source is based on the experimental values achieved at JAERI. The utilization of the cesium-seeded volume source is essential to the design of an efficient and compact neutral beam injection system which satisfies the ITER common design requirements. The critical components to realize this design are the 1.3MeV, 17A electrostatic accelerator and the high voltage DC acceleration power supply, whose performances must be demonstrated prior to the construction of ITER NBI system. (author)

  20. Optimization of acceleration and charge neutralization of a high-current ion beam in two accelerating gaps of an induction linear acceleration

    International Nuclear Information System (INIS)

    Belova, N.G.; Karas', V.I.

    1995-01-01

    Paper presents the results of numerical investigation into dynamics of high-current ion beam in two drift gap separated magnetoseparated accelerating gaps of linear induction accelerator. For eliminating imperfection one studies several variants of cold electron injection in a drift gap the enable to obtain satisfactory degree of charge and current neutralization of high-degree of charge and current neutralization of high-current ion beam

  1. Ion temperature anisotropy in high power helium neutral beam fuelling experiments in JET

    Energy Technology Data Exchange (ETDEWEB)

    Maas, A.C.; Core, W.G.F.; Gerstel, U.C.; Von Hellermann, M.G.; Koenig, R.W.T.; Marcus, F.B. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking

    1994-07-01

    During helium beam fuelling experiments in JET, distinctive anisotropic features have been observed in the velocity distribution function describing both fast and thermal alpha particle populations. During the initial fuelling phase the central helium ion temperature observed perpendicular to the magnetic field is higher than the central electron temperature, while the central helium ion temperature observed parallel to the magnetic field is lower than or equal to the central electron temperature. In order to verify temperature measurements of both perpendicular and parallel lines of sight, other independent methods of deducing the ion temperature are investigated: deuterium ion temperature, deuterium density, comparison with neutron rates and profiles (influence of a possible metastable population of helium). 6 refs., 7 figs.

  2. Ion-Ion Neutralization.

    Science.gov (United States)

    1982-05-31

    of Birmingam, P 0 Box 363, 2310/A2 Birmingham B15 2TT, England. 2303/GlAC II. Controlling Office Name and Address 12. Report Date Air Force Geophysics...source. Thus unwanted molecular excitation and dissociation can be avoided and greater control can be exercised in the creation of suitable plasma...The Fall fractigRal ionization density in these afterglow plagas (%-10 -𔃺) ensures that electron- neutral collisions are the most effective. This

  3. Neutral beamline with improved ion energy recovery

    Science.gov (United States)

    Kim, Jinchoon

    1984-01-01

    A neutral beamline employing direct energy recovery of unneutralized residual ions is provided which enhances the energy recovery of the full energy ion component of the beam exiting the neutralizer cell, and thus improves the overall neutral beamline efficiency. The unneutralized full energy ions exiting the neutralizer are deflected from the beam path and the electrons in the cell are blocked by a magnetic field applied transverse to the beam direction in the neutral izer exit region. The ions which are generated at essentially ground potential and accelerated through the neutralizer cell by a negative acceleration voltage are collected at ground potential. A neutralizer cell exit end region is provided which allows the magnetic and electric fields acting on the exiting ions to be loosely coupled. As a result, the fractional energy ions exiting the cell are reflected onto and collected at an interior wall of the neutralizer formed by the modified end geometry, and thus do not detract from the energy recovery efficiency of full energy ions exiting the cell. Electrons within the neutralizer are prevented from exiting the neutralizer end opening by the action of crossed fields drift (ExB) and are terminated to a collector collar around the downstream opening of the neutralizer. The correct combination of the extended neutralizer end structure and the magnet region is designed so as to maximize the exit of full energy ions and to contain the fractional energy ions.

  4. Multiaperture source for the production of low energy neutral beams using molecular ions

    International Nuclear Information System (INIS)

    Coupland, J.R.; Thompson, E.

    1974-01-01

    The construction and performance of a quasi dc multiaperture ion source and extraction system which has been developed for use on the Culham Superconducting Levitron experiment are described. Unlike other experiments utilizing neutral injection heating, which operate at energies greater than or equal to 20 keV with time scales approximately 10's of ms, the requirements for the levitron include relatively low energy less than or equal to 10 keV long plus length greater than or equal to 1 sec, and furthermore the input geometry is somewhat restrictive

  5. The development of the radio frequency driven negative ion source for neutral beam injectors (invited)a)

    Science.gov (United States)

    Kraus, W.; Fantz, U.; Franzen, P.; Fröschle, M.; Heinemann, B.; Riedl, R.; Wünderlich, D.

    2012-02-01

    Large and powerful negative hydrogen ion sources are required for the neutral beam injection (NBI) systems of future fusion devices. Simplicity and maintenance-free operation favors RF sources, which are developed intensively at the Max-Planck-Institut für Plasmaphysik (IPP) since many years. The negative hydrogen ions are generated by caesium-enhanced surface conversion of atoms and positive ions on the plasma grid surface. With a small scale prototype the required high ion current density and the low fraction of co-extracted electrons at low pressure as well as stable pulses up to 1 h could be demonstrated. The modular design allows extension to large source dimensions. This has led to the decision to choose RF sources for the NBI of the international fusion reactor, ITER. As an intermediate step towards the full size ITER source at IPP, the development will be continued with a half-size source on the new ELISE testbed. This will enable to gain experience for the first time with negative hydrogen ion beams from RF sources of these dimensions.

  6. Prompt Loss of Energetic Ions during Early Neutral Beam Injection in the National Spherical Torus Experiment

    Energy Technology Data Exchange (ETDEWEB)

    S.S. Medley; D.S. Darrow; D. Liu; A.L. Roquemore

    2005-03-25

    Early neutral-beam injection is used in the National Spherical Torus Experiment (NSTX) to heat the electrons and slow current penetration which keeps q(0) elevated to avoid deleterious MHD activity and at the same time reduces Ohmic flux consumption, all of which aids long-pulse operation. However, the low plasma current (I{sub p} {approx} 0.5 MA) and electron density (n{sub e} {approx} 1 x 10{sup 13} cm{sup -3}) attending early injection lead to elevated orbit and shine through losses. The inherent orbit losses are aggravated by large excursions in the outer gap width during current ramp-up. An investigation of this behavior using various energetic particle diagnostics on NSTX and TRANSP code analysis is presented.

  7. Commercialization of a high energy neutral beam ion source. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-12-21

    This final report summarizes the effort and presents the results of a Phase II fabrication effort to build an industrial prototype of the LBL developed high energy neutral beam source. The effort was primarily concentrated on incorporating hard vacuum dielectric seals and a ceramic high voltage accelerator insulator. Several other design changes were incorporated for cost, reliability or life improvements to include: (1) accelerator grid locating dowel pins to aid final alignment, (2) plasma source to accelerator captive fasteners to aid filament replacement during source maintenance, (3) molybdenum cooling tubes on all accelerator grids, (4) additional fasteners in the plasma generator to facilitate hard seals, (5) modified suppressor grid rails and holders to simplify final grid alignment, (6) adjusting screws on exit grid rail holders to simplify final grid alignment, (7) addition of adjusting screws to the grid end pieces to simplify alignment, and (8) addition of accelerator hat shims to allow two different grid positioning locations.

  8. Modeling of the negative ions extraction from a hydrogen plasma source. Application to ITER Neutral Beam Injector

    International Nuclear Information System (INIS)

    Mochalskyy, S.

    2011-12-01

    The development of a high performance negative ion (NI) source constitutes a crucial step in the construction of a Neutral Beam Injector of the future fusion reactor ITER. NI source should deliver 40 A of H - or of D - . To address this problem in a realistic way, a 3D particles-in-cell electrostatic collisional code was developed. Binary collisions between the particles are introduced using Monte-Carlo collision scheme. This code called ONIX was used to investigate the plasma properties and the transport of the charged particles close to a typical extraction aperture. Results obtained from this code are presented in this thesis. They include negative ions and electrons 3D trajectories. The ion and electron current density profiles are shown for different local magnetic field configurations. Results of production, destruction, and transport of H - in the extraction region are also presented. The production of H - is investigated via 3 atomic processes: 1) electron dissociative attachment to the vibrationally excited molecules H 2 (v) in the volume, 2) interaction of the positive ions H + and H 2 + with the aperture wall and 3) collisions of the neutral gas H, H 2 with aperture wall. The influence of each process on the total extracted NI current is discussed. The extraction efficiency of H - from the volume is compared to the one of H - coming from the wall. Moreover, a parametric study of the H - surface production is presented. Results show the role of sheath behavior in the vicinity of the aperture developing a double layer structure responsible of the NI extraction limitations. The 2 following issues are also analysed. First the influence of the external extracted potential value on the formation of negative sheath and secondly the strength of the magnetic filter on the total extracted NI and co-extracted electron current. The suppression of the electron beam by the negative ion produced at the plasma grid wall is also discussed. Results are in good agreement

  9. Control and data acquisition of the ITER full-scale ion source for the neutral beam test facility

    Energy Technology Data Exchange (ETDEWEB)

    Luchetta, Adriano, E-mail: adriano.luchetta@igi.cnr.it [Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Padova (Italy); Manduchi, Gabriele; Taliercio, Cesare [Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Padova (Italy); Paolucci, Francesco; Sartori, Filippo [Fusion for Energy, Barcelona (Spain); Svensson, Lennart [ITER Organization, Route de Vinon-sur-Verdon, CS 90046 St. Paul Lez Durance (France); Labate, Carmelo Vincenzo [Association ENEA-CREATE, Department of Engineering, University of Naples “Parthenope” (Italy); Breda, Mauro; Capobianco, Roberto; Molon, Federico; Moressa, Modesto; Simionato, Paola; Zampiva, Enrico; Barbato, Paolo; Polato, Sandro [Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Padova (Italy)

    2015-10-15

    Highlights: • This paper describes the requirements and architecture of the control and data acquisition system of the ITER full-ion source experiment in the neutral beam test facility. • The system architecture integrates various popular software frameworks. • Slow control is based on the EPICS (Experimental Physics and Industrial Control System) framework. • Fast control is based on the MARTe (Multi-threaded Application Real-Time executor) framework. • Data acquisition is based on the MDSplus framework. - Abstract: The neutral beam test facility, which is under construction in Padova, Italy, is developing the ITER full-scale ion source for the ITER heating neutral beam injectors, referred to as the SPIDER experiment, and the full-size prototype injector, referred to as MITICA. The SPIDER control and data acquisition system (CODAS) has been developed and its construction will start in 2014. Slow control and data acquisition will be based on the ITER CODAC core system software suite that has been designed to facilitate the integration of ITER plant systems with CODAC. Fast control and data acquisition will use solutions specific to the test facility, as the corresponding concepts are not ready-to-use in the ITER design. The ITER hardware catalog for fast control has been taken into consideration. The software development will be based on the integration of MDSplus and MARTe, two framework software packages that are well known in the fusion community, targeting data organization and fast real-time control, respectively. The paper revises the system requirements and the system design and shows the results already achieved in terms of system integration. In addition, the paper will report the experience in the usage of different cooperating software frameworks and in the integration of industrial procured plant systems.

  10. Negative ion formation and neutralization processes, (1)

    International Nuclear Information System (INIS)

    Sugiura, Toshio

    1982-01-01

    This review has been made preliminary for the purpose of contribute to the plasma heating by ''negative ion based neutral beam injection'' in the magnetic confinement fusion reactor. A compilation includes the survey of the general processes of negative ion formation, the data of the cross section of H - ion formation and the neutralization of H - ion, and some of new processes of H - ion formation. The data of cross section are mainly experimental, but partly include the results of theoretical calculation. (author)

  11. TFTR neutral beam power system

    International Nuclear Information System (INIS)

    Deitz, A.; Murray, H.; Winje, R.

    1977-01-01

    The TFTR NB System will be composed of four beam lines, each containing three ion sources presently being developed for TFTR by the Lawrence Berkeley Laboratories (LBL). The Neutral Beam Power System (NBPS) will provide the necessary power required to operate these Ion Sources in both an experimental or operational mode as well as test mode. This paper describes the technical as well as the administrative/management aspects involved in the development and building of this system. The NBPS will combine the aspects of HV pulse (120 kV) and long pulse width (0.5 sec) together to produce a high power system that is unique in the Electrical Engineering field

  12. BEAMS3D Neutral Beam Injection Model

    Energy Technology Data Exchange (ETDEWEB)

    Lazerson, Samuel

    2014-04-14

    With the advent of applied 3D fi elds in Tokamaks and modern high performance stellarators, a need has arisen to address non-axisymmetric effects on neutral beam heating and fueling. We report on the development of a fully 3D neutral beam injection (NBI) model, BEAMS3D, which addresses this need by coupling 3D equilibria to a guiding center code capable of modeling neutral and charged particle trajectories across the separatrix and into the plasma core. Ionization, neutralization, charge-exchange, viscous velocity reduction, and pitch angle scattering are modeled with the ADAS atomic physics database [1]. Benchmark calculations are presented to validate the collisionless particle orbits, neutral beam injection model, frictional drag, and pitch angle scattering effects. A calculation of neutral beam heating in the NCSX device is performed, highlighting the capability of the code to handle 3D magnetic fields.

  13. Investigation of beam deflection reduction and multi-beamlet focus at a large-area negative ion source for a neutral beam injector with 3-D beam trajectory simulation

    CERN Document Server

    Tanaka, M; Asano, E; Oka, Y; Osakabe, M; Tsumori, K; Kaneko, O; Yamashita, Y

    2000-01-01

    We investigated the reduction of ion beam deflection caused by electron deflection magnets, and focus of multi-beamlets at a large-area negative ion source of a neutral beam injector (NBI) in order to reduce beam loss during long-distance beam transport (>10 m) and beam injection into a nuclear fusion device. The electrostatic lens effect by displacement of the beam extraction aperture of a grounded grid (GG) was utilized for the beam deflection reduction and the multi-beamlet focus. We proposed an analysis process to adjust the aperture displacement which avoids beam collision with the GG by too much displacement. The analysis process includes a 3-D beam trajectory simulation used for analyzing the beam deflection angle and beam radius as well as theoretical calculations, which are used to calculate the aperture displacement based on the 3-D simulation results. Applicability of the analysis process was examined for a large-area high-current H sup - ion source of an NBI (0.25 mx1.25 m, 40 A, 180 keV). The ana...

  14. ICAN: High power neutral beam generation

    International Nuclear Information System (INIS)

    Moustaizis, S.D.; Lalousis, P.; Perrakis, K.; Auvray, P.; Larour, J.; Ducret, J.E.; Balcou, P.

    2015-01-01

    During the last few years there is an increasing interest on the development of alternative high power new negative ion source for Tokamak applications. The proposed new neutral beam device presents a number of advantages with respect to: the density current, the acceleration voltage, the relative compact dimension of the negative ion source, and the coupling of a high power laser beam for photo-neutralization of the negative ion beam. Here we numerically investigate, using a multi- fluid 1-D code, the acceleration and the extraction of high power ion beam from a Magnetically Insulated Diode (MID). The diode configuration will be coupled to a high power device capable of extracting a current up to a few kA with an accelerating voltage up to MeV. An efficiency of up to 92% of the coupling of the laser beam, is required in order to obtain a high power, up to GW, neutral beam. The new high energy, high average power, high efficiency (up to 30%) ICAN fiber laser is proposed for both the plasma generation and the photo-neutralizer configuration. (authors)

  15. Consistency checks in beam emission modeling for neutral beam injectors

    International Nuclear Information System (INIS)

    Punyapu, Bharathi; Vattipalle, Prahlad; Sharma, Sanjeev Kumar; Baruah, Ujjwal Kumar; Crowley, Brendan

    2015-01-01

    In positive neutral beam systems, the beam parameters such as ion species fractions, power fractions and beam divergence are routinely measured using Doppler shifted beam emission spectrum. The accuracy with which these parameters are estimated depend on the accuracy of the atomic modeling involved in these estimations. In this work, an effective procedure to check the consistency of the beam emission modeling in neutral beam injectors is proposed. As a first consistency check, at a constant beam voltage and current, the intensity of the beam emission spectrum is measured by varying the pressure in the neutralizer. Then, the scaling of measured intensity of un-shifted (target) and Doppler shifted intensities (projectile) of the beam emission spectrum at these pressure values are studied. If the un-shifted component scales with pressure, then the intensity of this component will be used as a second consistency check on the beam emission modeling. As a further check, the modeled beam fractions and emission cross sections of projectile and target are used to predict the intensity of the un-shifted component and then compared with the value of measured target intensity. An agreement between the predicted and measured target intensities provide the degree of discrepancy in the beam emission modeling. In order to test this methodology, a systematic analysis of Doppler shift spectroscopy data obtained on the JET neutral beam test stand data was carried out

  16. Design of the ITER Neutral Beam injectors

    International Nuclear Information System (INIS)

    Hemsworth, R.S.; Feist, J.; Hanada, M.; Heinemann, B.; Inoue, T.; Kuessel, E.; Kulygin, V.; Krylov, A.; Lotte, P.; Miyamoto, K.; Miyamoto, N.; Murdoch, D.; Nagase, A.; Ohara, Y.; Okumura, Y.; Pamela, J.; Panasenkov, A.; Shibata, K.; Tanii, M.

    1996-01-01

    This paper describes the Neutral Beam Injection system which is presently being designed in Europe, Japan and Russia, with co-ordination by the Joint Central Team of ITER at Naka, Japan. The proposed system consists of three negative ion based neutral injectors, delivering a total of 50 MW of 1 MeV D 0 to the ITER plasma for pulse length of ≥1000 s. The injectors each use a single caesiated volume arc discharge negative ion source, and a multi-grid, multi-aperture accelerator, to produce about 40 A of 1 MeV D - . This will be neutralized in a sub-divided gas neutralizer, which has a conversion efficiency of about 60%. The charged fraction of the beam emerging from the neutralizer is dumped in an electrostatic residual ion dump. A water cooled calorimeter can be moved into the beam path to intercept the neutral beam, allowing commissioning of the injector independent of ITER. copyright 1996 American Institute of Physics

  17. Development of bucket ion source for JFT-2M neutral beam injector

    International Nuclear Information System (INIS)

    Shibata, Takatoshi; Kazawa, Minoru; Yokoyama, Kenji; Shibuya, Toshihiro; Honda, Atsushi; Shiina, Tomio

    1987-02-01

    Detailed description is given of a new Bucket Ion Source for NBI heating experiments on JFT-2M. The source is designed to achieve the high proton ratio (∼ 80 %) as well as high power. Results of the performance test is also given. (author)

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

    International Nuclear Information System (INIS)

    1981-09-01

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

  19. Controlling Charge and Current Neutralization of an Ion Beam Pulse in a Background Plasma by Application of a Solenoidal Magnetic Field I: Weak Magnetic Field Limit

    Energy Technology Data Exchange (ETDEWEB)

    Kaganovich, I. D., Startsev, E. A., Sefkow, A. B., Davidson, R. C.

    2008-10-10

    Propagation of an intense charged particle beam pulse through a background plasma is a common problem in astrophysics and plasma applications. The plasma can effectively neutralize the charge and current of the beam pulse, and thus provides a convenient medium for beam transport. The application of a small solenoidal magnetic field can drastically change the self-magnetic and self- electric fields of the beam pulse, thus allowing effective control of the beam transport through the background plasma. An analytic model is developed to describe the self-magnetic field of a finite- length ion beam pulse propagating in a cold background plasma in a solenoidal magnetic field. The analytic studies show that the solenoidal magnetic field starts to infuence the self-electric and self-magnetic fields when ωce > ωpeβb, where ωce = eβ/mec is the electron gyrofrequency, ωpe is the electron plasma frequency, and βb = Vb/c is the ion beam velocity relative to the speed of light. This condition typically holds for relatively small magnetic fields (about 100G). Analytical formulas are derived for the effective radial force acting on the beam ions, which can be used to minimize beam pinching. The results of analytic theory have been verified by comparison with the simulation results obtained from two particle-in-cell codes, which show good agreement.

  20. Controlling Charge and Current Neutralization of an Ion Beam Pulse in a Background Plasma by Application of a Solenoidal Magnetic Field I: Weak Magnetic Field Limit

    International Nuclear Information System (INIS)

    Kaganovich, I. D.; Startsev, E. A.; Sefkow, A. B.; Davidson, R. C.

    2008-01-01

    Propagation of an intense charged particle beam pulse through a background plasma is a common problem in astrophysics and plasma applications. The plasma can effectively neutralize the charge and current of the beam pulse, and thus provides a convenient medium for beam transport. The application of a small solenoidal magnetic field can drastically change the self-magnetic and self- electric fields of the beam pulse, thus allowing effective control of the beam transport through the background plasma. An analytic model is developed to describe the self-magnetic field of a finite-length ion beam pulse propagating in a cold background plasma in a solenoidal magnetic field. The analytic studies show that the solenoidal magnetic field starts to influence the self-electric and self-magnetic fields when ω ce ∼> ω pe β b , where ω ce = eB/m e c is the electron gyrofrequency, ω pe is the electron plasma frequency, and β b = V b /c is the ion beam velocity relative to the speed of light. This condition typically holds for relatively small magnetic fields (about 100G). Analytical formulas are derived for the effective radial force acting on the beam ions, which can be used to minimize beam pinching. The results of analytic theory have been verified by comparison with the simulation results obtained from two particle-in-cell codes, which show good agreement

  1. Development of KSTAR Neutral Beam Heating System

    Energy Technology Data Exchange (ETDEWEB)

    Oh, B. H.; Song, W. S.; Yoon, B. J. (and others)

    2007-10-15

    The prototype components of a neutral beam injection (NBI) system have been developed for the KSTAR, and a capability of the manufactured components has been tested. High power ion source, acceleration power supply, other ion source power supplies, neutralizer, bending magnet for ion beam separation, calorimeter, and cryo-sorption pump have been developed by using the domestic technologies and tested for a neutral beam injection of 8 MW per beamline with a pulse duration of 300 seconds. The developed components have been continuously upgraded to achieve the design requirements. The development technology of high power and long pulse neutral beam injection system has been proved with the achievement of 5.2 MW output for a short pulse length and 1.6 MW output for a pulse length of 300 seconds. Using these development technologies, the domestic NB technology has been stabilized under the development of high power ion source, NB beamline components, high voltage and current power supplies, NB diagnostics, NB system operation and control.

  2. Neutral Particle Analyzer Measurements of Ion Behavior in NSTX

    Energy Technology Data Exchange (ETDEWEB)

    S.S. Medley; R.E. Bell; D.S. Darrow; A.L. Roquemore

    2002-02-06

    Initial results obtained with the Neutral Particle Analyzer (NPA) diagnostic on the National Spherical Torus Experiment (NSTX) are presented. Magnetohydrodynamic activity and reconnection events cause depletion of the deuterium energetic ion distribution created by neutral-beam injection. Adding High Harmonic Fast Wave Heating to neutral-beam-heated discharges results in the generation of an energetic ion tail above the beam injection energy. NPA measurements of the residual hydrogen ion temperature are in good agreement with those from recombination spectroscopy.

  3. Electrostatic probe diagnostics on the LBL 10 ampere neutral beam ion source

    International Nuclear Information System (INIS)

    Schoenberg, K.F.

    1978-08-01

    The experimental results of electrostatic probe measurements on the LBL 10 ampere ion source are presented. Data is obtained via a pulsed acquisition system which digitally records a probe characteristic and its first and second derivatives. The latter are shown to be proportional to the projected electron energy distribution function, and the isotropic electron energy distribution function, respectively. System performance for distribution function measurement is compared to the established technique of harmonic analysis. A complete analysis of the data acquisition system and its experimental accuracy is presented

  4. PDX neutral-beam reionization losses

    International Nuclear Information System (INIS)

    Kugel, H.W.; Dylla, H.F.; Eubank, H.P.; Kozub, T.A.; Moore, R.; Schilling, G.; Stewart, L.D.; von Halle, A.; Williams, M.D.

    1982-02-01

    Reionization losses for 1.5 MW H 0 and 2 MW D 0 neutral beams injected into the PDX tokamak were studied using pressure gauges, photo-transistors, thermocouples, surface shielding, and surface sample analysis. Considerable outgassing of conventionally prepared 304SS ducts occurred during initial injections and gradually decreased with the cumulative absorption of beam power. Reionization power losses are presently about 5% in the ducts and about 12% total for a beamline including the duct. Present duct pressures are attributed primarily to gas from the ion source and neutralizer with much smaller contributions from residual wall desorption. Physical mechanisms for the observed duct outgassing are discussed

  5. ISX-B neutral beams and the beam target experiment

    Energy Technology Data Exchange (ETDEWEB)

    Bates, S.C.; Edmonds, P.H.; Kim, J.; Bush, C.E.; Massengill, L.A.; Overbey, D.R.; Pearce, J.W.

    1980-10-01

    This report describes the hardware and operation of the ISX neutral beamlines as well as an experiment done to verify estimates of the neutral power injected into the tokamak. Tangential coinjection of megawatt levels of 30 to 40-keV neutrals into the tokamak has made the study of high-beta plasmas in ISX possible. These power levels were achieved with high reliability (over 90%) by two neutral beamlines with design power ratings of 900 kW of H/sup 0/ (upgraded to 1.5 MW) each. The neutral beamlines consist of a duoPIGatron plasma generator, acceleration grids, a gas neutralization cell, an ion deflection magnet, beam calorimetry, high-speed helium cryocondensation vacuum pumps, and associated electrical and control systems. The beamlines and their operation are described briefly with an emphasis on their relation to injection into a plasma. Neutral injection geometry with respect to the tokamak is given.

  6. 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

  7. Plasma heating with multi-MeV neutral atom beams

    Energy Technology Data Exchange (ETDEWEB)

    Grisham, L.R.; Post, D.E.; Mikkelsen, D.R.; Eubank, H.P.

    1981-10-01

    We explore the utility and feasibility of neutral beams of greater than or equal to 6 AMU formed from negative ions, and also of D/sup 0/ formed from D/sup -/. The negative ions would be accelerated to approx. 1 to 2 MeV/AMU and neutralized, whereupon the neutral atoms would be used to heat and, perhaps, to drive current in magnetically confined plasmas. Such beams appear feasible and offer the promise of significant advantages relative to conventional neutral beams based on positive deuterium ions at approx. 150 keV.

  8. TPX Neutral Beam Injection System design

    International Nuclear Information System (INIS)

    von Halle, A.; Bowen, O.N.; Edwards, J.W.

    1993-01-01

    The existing Tokamak Fusion Test Reactor Neutral Beam system is proposed to be modified for long pulse operation on the Tokamak Physics Experiment (TPX). Day one of TPX will call for one TFTR beamline modified for 1000 second pulse lengths oriented co-directional to the plasma current. The system design will be capable of accommodating an additional co-directional and a single counter directional beamline. For the TPX conceptual design, every attempt was made to use existing Neutral Beam hardware, plant facilities, auxiliary systems, service infrastructure, and control systems. This paper describes the moderate modifications required to the power systems, the ion sources, and the beam impinged surfaces of the ion dumps, the calorimeters, the various beam scrapers, and the neutralizers. Also described are the minimal modifications required to the vacuum, cryogenic, and gas systems and the major modification of replacing the beamline-torus duct in its entirety. Operational considerations for Neutral Beam subsystems over 1000 second pulse lengths will be explored including proposed operating scenarios for full steady state operation

  9. New ORNL neutral beam transport system

    International Nuclear Information System (INIS)

    Stirling, W.L.; Davis, R.C.; Haselton, H.H.; Schnechter, D.E.; Tsai, C.C.

    1977-01-01

    The Princeton Large Torus (PLT) neutral beam injection systems have proven themselves to be a solid foundation on which next generation systems can be based. There are two areas in the new systems receiving particular emphasis: (a) increased power per beam line and (b) higher beam transmission efficiency. Two different methods are being investigated to improve the transmission efficiency. First the drift tube region, the region of the beam line between the vacuum chamber housing the ion source and the torus, is being enlarged. In this manner a second, large cryopump will be installed in the drift tube to lower the pressure to approx.10 -5 torr. Thus, neutral beam reionization on the background gas will be significantly reduced from the measured losses at a few 10 -4 torr of the PLT system. Second, the beam divergence will be reduced by application of one or more of three known techniques developed on a single aperture source in the laboratory. Each of these methods has shown a reduction in single beamlet divergence from theta/sub HWHM/ approx. 1 0 to approx.0.5 0 . The low beamlet divergence coupled with a differentially pumped drift tube will effectively accommodate the larger ion sources under development. All future beam line systems will benefit either directly or indirectly from the experience gained operating and upgrading the PLT beam line concept

  10. Development of neutral beam source using electron beam excited plasma

    International Nuclear Information System (INIS)

    Hara, Yasuhiro; Hamagaki, Manabu; Mise, Takaya; Hara, Tamio

    2011-01-01

    A low-energy neutral beam (NB) source, which consists of an electron-beam-excited plasma (EBEP) source and two carbon electrodes, has been developed for damageless etching of ultra-large-scale integrated (ULSI) devices. It has been confirmed that the Ar ion beam energy was controlled by the acceleration voltage and the beam profile had good uniformity over the diameter of 80 mm. Dry etching of a Si wafer at the floating potential has been carried out by Ar NB. Si sputtering yield by an Ar NB clearly depends on the acceleration voltage. This result shows that the NB has been generated through the charge exchange reaction from the ion beam in the process chamber. (author)

  11. PLT neutral beam injection systems

    International Nuclear Information System (INIS)

    Menon, M.M.; Barber, G.C.; Blue, C.W.

    1979-01-01

    A brief description of the Princeton Large Torus (PLT) neutral beam injection system is given and its performance characteristics are outlined. A detailed operational procedure is included, as are some tips on troubleshooting. Proper operation of the source is shown to be a crucial factor in system performance

  12. The ion source development for neutral injection heating at JAERI

    International Nuclear Information System (INIS)

    Shirakata, H.; Itoh, T.; Kondoh, U.; Matsuda, S.; Ohara, Y.; Ohga, T.; Shibata, T.; Sugawara, T.; Tanaka, S.

    1976-01-01

    The neutral beam research and development effort at JAERI has been mainly concentrated on design, construction and testing of ion sources needed for present and planned heating experiments. Fundamental characteristics of the ion sources developed are described

  13. Doppler-shifted neutral beam line shape and beam transmission

    Energy Technology Data Exchange (ETDEWEB)

    Kamperschroer, J.H.; Grisham, L.R.; Kokatnur, N.; Lagin, L.J.; Newman, R.A.; O`Connor, T.E.; Stevenson, T.N.; von Halle, A.

    1994-04-01

    Analysis of Doppler-shifted Balmer-{alpha} line emission from the TFTR neutral beam injection systems has revealed that the line shape is well approximated by the sum of two Gaussians, or, alternatively, by a Lorentzian. For the sum of two Gaussians, the broad portion of the distribution contains 40% of the beam power and has a divergence five times that of the narrow part. Assuming a narrow 1/e- divergence of 1.3{degrees} (based on fits to the beam shape on the calorimeter), the broad part has a divergence of 6.9{degrees}. The entire line shape is also well approximated by a Lorentzian with a half-maximum divergence of 0.9{degrees}. Up to now, fusion neutral beam modelers have assumed a single Gaussian velocity distribution, at the extraction plane, in each direction perpendicular to beam propagation. This predicts a beam transmission efficiency from the ion source to the calorimeter of 97%. Waterflow calorimetry data, however, yield a transmission efficiency of {approximately}75%, a value in rough agreement with predictions of the Gaussian or Lorentzian models presented here. The broad wing of the two Gaussian distribution also accurately predicts the loss in the neutralizer. An average angle of incidence for beam loss at the exit of the neutralizer is 2.2{degrees}, rather than the 4.95{degrees} subtended by the center of the ion source. This average angle of incidence, which is used in computing power densities on collimators, is shown to be a function of beam divergence.

  14. Doppler-shifted neutral beam line shape and beam transmission

    International Nuclear Information System (INIS)

    Kamperschroer, J.H.; Grisham, L.R.; Kokatnur, N.; Lagin, L.J.; Newman, R.A.; O'Connor, T.E.; Stevenson, T.N.; von Halle, A.

    1994-04-01

    Analysis of Doppler-shifted Balmer-α line emission from the TFTR neutral beam injection systems has revealed that the line shape is well approximated by the sum of two Gaussians, or, alternatively, by a Lorentzian. For the sum of two Gaussians, the broad portion of the distribution contains 40% of the beam power and has a divergence five times that of the narrow part. Assuming a narrow 1/e- divergence of 1.3 degrees (based on fits to the beam shape on the calorimeter), the broad part has a divergence of 6.9 degrees. The entire line shape is also well approximated by a Lorentzian with a half-maximum divergence of 0.9 degrees. Up to now, fusion neutral beam modelers have assumed a single Gaussian velocity distribution, at the extraction plane, in each direction perpendicular to beam propagation. This predicts a beam transmission efficiency from the ion source to the calorimeter of 97%. Waterflow calorimetry data, however, yield a transmission efficiency of ∼75%, a value in rough agreement with predictions of the Gaussian or Lorentzian models presented here. The broad wing of the two Gaussian distribution also accurately predicts the loss in the neutralizer. An average angle of incidence for beam loss at the exit of the neutralizer is 2.2 degrees, rather than the 4.95 degrees subtended by the center of the ion source. This average angle of incidence, which is used in computing power densities on collimators, is shown to be a function of beam divergence

  15. Neutral beams for magnetic fusion

    International Nuclear Information System (INIS)

    Hooper, B.

    1977-01-01

    Significant advances in forming energetic beams of neutral hydrogen and deuterium atoms have led to a breakthrough in magnetic fusion: neutral beams are now heating plasmas to thermonuclear temperatures, here at LLL and at other laboratories. For example, in our 2XIIB experiment we have injected a 500-A-equivalent current of neutral deuterium atoms at an average energy of 18 keV, producing a dense plasma (10 14 particles/cm 3 ) at thermonuclear energy (14 keV or 160 million kelvins). Currently, LLL and LBL are developing beam energies in the 80- to 120-keV range for our upcoming MFTF experiment, for the TFTR tokamak experiment at Princeton, and for the Doublet III tokamak experiment at General Atomic. These results increase our long-range prospects of producing high-intensity beams of energies in the hundreds or even thousands of kilo-electron-volts, providing us with optimistic extrapolations for realizing power-producing fusion reactors

  16. A Neutral Beam Injector Upgrade for NSTX

    International Nuclear Information System (INIS)

    Stevenson, T.; McCormack, B.; Loesser, G.D.; Kalish, M.; Ramakrishnan, S.; Grisham, L.; Edwards, J.; Cropper, M.; Rossi, G.; Halle, A. von; Williams, M.

    2002-01-01

    The National Spherical Torus Experiment (NSTX) capability with a Neutral Beam Injector (NBI) capable of 80 kiloelectronvolt (keV), 5 Megawatt (MW), 5 second operation. This 5.95 million dollar upgrade reused a previous generation injector and equipment for technical, cost, and schedule reasons to obtain these specifications while retaining a legacy capability of 120 keV neutral particle beam delivery for shorter pulse lengths for possible future NSTX experiments. Concerns with NBI injection included power deposition in the plasma, aiming angles from the fixed NBI fan array, density profiles and beam shine through, orbit losses of beam particles, and protection of the vacuum vessel wall against beam impingement. The upgrade made use of the beamline and cryo panels from the Neutral Beam Test Stand facility, existing power supplies and controls, beamline components and equipment not contaminated by tritium during DT [deuterium-tritium] experiments, and a liquid Helium refrigerator plant to power and cryogenically pump a beamline and three ion sources. All of the Tokamak Fusion Test Reactor (TFTR) ion sources had been contaminated with tritium, so a refurbishment effort was undertaken on selected TFTR sources to rid the three sources destined for the NSTX NBI of as much tritium as possible. An interconnecting duct was fabricated using some spare and some new components to attach the beamline to the NSTX vacuum vessel. Internal vacuum vessel armor using carbon tiles was added to protect the stainless steel vacuum vessel from beam impingement in the absence of plasma and interlock failure. To date, the NBI has operated to 80 keV and 5 MW and has injected requested power levels into NSTX plasmas with good initial results, including high beta and strong heating characteristics at full rated plasma current

  17. Ion beam monitoring

    International Nuclear Information System (INIS)

    McKinney, C.R.

    1980-01-01

    An ion beam analyzer is specified, having an ion source for generating ions of a sample to be analyzed, means for extracting the sample ions, means for focusing the sample ions into a beam, separation means positioned along the ion beam for selectively deflecting species of ions, and means for detecting the selected species of ions. According to the specification, the analyzer further comprises (a) means for disabling at least a portion of the separation means, such that the ion beam from the source remains undeflected; (b) means located along the path of the undeflected ion beam for sensing the sample ions; and (c) enabling means responsive to the sensing means for automatically re-enabling the separation means when the sample ions reach a predetermined intensity level. (author)

  18. Plasma/Neutral-Beam Etching Apparatus

    Science.gov (United States)

    Langer, William; Cohen, Samuel; Cuthbertson, John; Manos, Dennis; Motley, Robert

    1989-01-01

    Energies of neutral particles controllable. Apparatus developed to produce intense beams of reactant atoms for simulating low-Earth-orbit oxygen erosion, for studying beam-gas collisions, and for etching semiconductor substrates. Neutral beam formed by neutralization and reflection of accelerated plasma on metal plate. Plasma ejected from coaxial plasma gun toward neutralizing plate, where turned into beam of atoms or molecules and aimed at substrate to be etched.

  19. 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.

  20. 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

  1. Intense nonrelativistic cesium ion beam

    International Nuclear Information System (INIS)

    Lampel, M.C.

    1984-01-01

    The Heavy Ion Fusion group at Lawrence Berkeley Laboratory has constructed the One Ampere Cesium injector as a proof of principle source to supply an induction linac with a high charge density and high brightness ion beam. This is studied here. An electron beam probe was developed as the major diagnostic tool for characterizing ion beam space charge. Electron beam probe data inversion is accomplished with the EBEAM code and a parametrically adjusted model radial charge distribution. The longitudinal charge distribution was not derived, although it is possible to do so. The radial charge distribution that is derived reveals an unexpected halo of trapped electrons surrounding the ion beam. A charge fluid theory of the effect of finite electron temperature on the focusing of neutralized ion beams (Nucl Fus. 21, 529(1981)) is applied to the problem of the cesium beam final focus at the end of the injector. It is shown that the theory's predictions and assumptions are consistent with the experimental data, and that it accounts for the observed ion beam radius of approx.5 cm and the electron halo, including the determination of an electron Debye length of approx.10 cm

  2. Ion beam diagnosis

    International Nuclear Information System (INIS)

    Strehl, P.

    1994-04-01

    This report is an introduction to ion beam diagnosis. After a short description of the most important ion beam parameters measurements of the beam current by means of Faraday cups, calorimetry, and beam current transformers and measurements of the beam profile by means of viewing screens, profile grids and scanning devices, and residual gas ionization monitors are described. Finally measurements in the transverse and longitudinal phase space are considered. (HSI)

  3. Analysis of particle species evolution in neutral beam injection lines

    International Nuclear Information System (INIS)

    Kim, J.; Haselton, H.H.

    1978-07-01

    Analytic solutions to the rate equations describing the species evolution of a multispecies positive ion beam of hydrogen due to charge exchange and molecular dissociation are derived as a function of the background gas (H 2 ) line density in the neutralizing gas cell and in the drift tube. Using the solutions, calculations are presented for the relative abundance of each species as a function of the gas cell thickness, the reionization loss rates in the drift tube, and the neutral beam power as a function of the beam energy and the species composition of the original ion beam

  4. Dynamics of alkali ions-neutral molecules reactions: Radio frequency-guided beam experimental cross-sections and direct quasiclassical trajectory studies

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar, J.; Andres, J. de; Lucas, J. M.; Alberti, M.; Huarte-Larranaga, F.; Bassi, D.; Aguilar, A. [Departament de Quimica Fisica, Institut de Quimica Teorica i Computacional (IQTCUB), Universitat de Barcelona, Marti i Franques, 1, 08028 Barcelona (Spain); Dipartimento di Fisica, Universita degli Studi di Trento, 38123 Povo-Trento (Italy); Departament de Quimica Fisica, Institut de Quimica Teorica i Computacional (IQTCUB), Universitat de Barcelona, Marti i Franques, 1, 08028 Barcelona (Spain)

    2012-11-27

    Different reactive processes taking place in collisions between alkali ions and neutral i-C{sub 3}H{sub 7}Cl molecules in the low (center of mass frame) energy range have been studied using an octopole radiofrequency guided-ion-beam apparatus developed in our laboratory. Cross-section energy dependences for all these reactions have been obtained in absolute units. Ab initio electronic structure calculations for those colliding systems evolving on the ground single potential surface have given relevant information on the main topological features of the surfaces. For some of the reactions a dynamic study by 'on the fly' trajectories has complemented the available experimental and electronic structure information.

  5. Neutral Beam Development for the Lockheed Martin Compact Fusion Reactor

    Science.gov (United States)

    Ebersohn, Frans; Sullivan, Regina

    2017-10-01

    The Compact Fusion Reactor project at Lockheed Martin Skunk Works is developing a neutral beam injection system for plasma heating. The neutral beam plasma source consists of a high current lanthanum hexaboride (LaB6) hollow cathode which drives an azimuthal cusp discharge similar to gridded ion thrusters. The beam is extracted with a set of focusing grids and is then neutralized in a chamber pumped with Titanium gettering. The design, testing, and analyses of individual components are presented along with the most current full system results. The goal of this project is to advance in-house neutral beam expertise at Lockheed Martin to aid in operation, procurement, and development of neutral beam technology. ©2017 Lockheed Martin Corporation. All Rights Reserved.

  6. Electron Beam Ion Sources

    CERN Document Server

    Zschornacka, G.; Thorn, A.

    2013-12-16

    Electron beam ion sources (EBISs) are ion sources that work based on the principle of electron impact ionization, allowing the production of very highly charged ions. The ions produced can be extracted as a DC ion beam as well as ion pulses of different time structures. In comparison to most of the other known ion sources, EBISs feature ion beams with very good beam emittances and a low energy spread. Furthermore, EBISs are excellent sources of photons (X-rays, ultraviolet, extreme ultraviolet, visible light) from highly charged ions. This chapter gives an overview of EBIS physics, the principle of operation, and the known technical solutions. Using examples, the performance of EBISs as well as their applications in various fields of basic research, technology and medicine are discussed.

  7. Targets for high power neutral beams

    International Nuclear Information System (INIS)

    Kim, J.

    1980-01-01

    Stopping high-power, long-pulse beams is fast becoming an engineering challenge, particularly in neutral beam injectors for heating magnetically confined plasmas. A brief review of neutral beam target technology is presented along with heat transfer calculations for some selected target designs

  8. Manufacturing, assembly and tests of SPIDER Vacuum Vessel to develop and test a prototype of ITER neutral beam ion source

    Energy Technology Data Exchange (ETDEWEB)

    Zaccaria, Pierluigi, E-mail: pierluigi.zaccaria@igi.cnr.it [Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete S.p.A.), Padova (Italy); Valente, Matteo; Rigato, Wladi; Dal Bello, Samuele; Marcuzzi, Diego; Agostini, Fabio Degli; Rossetto, Federico; Tollin, Marco [Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete S.p.A.), Padova (Italy); Masiello, Antonio [Fusion for Energy F4E, Barcelona (Spain); Corniani, Giorgio; Badalocchi, Matteo; Bettero, Riccardo; Rizzetto, Dario [Ettore Zanon S.p.A., Schio (VI) (Italy)

    2015-10-15

    Highlights: • The SPIDER experiment aims to qualify and optimize the ion source for ITER injectors. • The large SPIDER Vacuum Vessel was built and it is under testing at the supplier. • The main working and assembly steps for production are presented in the paper. - Abstract: The SPIDER experiment (Source for the Production of Ions of Deuterium Extracted from an RF plasma) aims to qualify and optimize the full size prototype of the negative ion source foreseen for MITICA (full size ITER injector prototype) and the ITER Heating and Current Drive Injectors. Both SPIDER and MITICA experiments are presently under construction at Consorzio RFX in Padova (I), with the financial support from IO (ITER Organization), Fusion for Energy, Italian research institutions and contributions from Japan and India Domestic Agencies. The vacuum vessel hosting the SPIDER in-vessel components (Beam Source and calorimeters) has been manufactured, assembled and tested during the last two years 2013–2014. The cylindrical vessel, about 6 m long and 4 m in diameter, is composed of two cylindrical modules and two torispherical lids at the ends. All the parts are made by AISI 304 L stainless steel. The possibility of opening/closing the vessel for monitoring, maintenance or modifications of internal components is guaranteed by bolted junctions and suitable movable support structures running on rails fixed to the building floor. A large number of ports, about one hundred, are present on the vessel walls for diagnostic and service purposes. The main working steps for construction and specific technological issues encountered and solved for production are presented in the paper. Assembly sequences and tests on site are furthermore described in detail, highlighting all the criteria and requirements for correct positioning and testing of performances.

  9. Diagnostics for hot plasmas using hydrogen neutral beams

    International Nuclear Information System (INIS)

    Goldston, R.J.

    1982-12-01

    Beams of neutral hydrogen atoms have found a number of uses in the diagnosis of hot plasmas. In the most straightforward application, neutral beams have been used to determine plasma line density, based on simple attenuation measurements. This technique has been applied most intensively recently to the study of beam-injected mirror plasmas. Neutral beams have also now been used in a number of tokamaks to supply a local increase of the neutral atom target density for charge exchange. By directing a time-modulated neutral beam across the sight-line of a charge-exchange analyzer, and measuring the modulated neutral particle efflux from the plasma, local measurements of the ion energy distribution function can be made. If a modulated diagnostic neutral beam is directed across the sight-line of an ultra-violet spectrometer, one can also make measurements of the local densities and possibly velocity distributions of fully stripped impurities. The fast hydrogen neutrals charge exchange with fully stripped impurities in the plasma, leaving the impurities in excited hydrogen-like states. In their prompt radiative decay the impurity ions emit characteristic uv lines, which can be detected easily

  10. Neutral Beam Injection for Plasma and Magnetic Field Diagnostics

    International Nuclear Information System (INIS)

    Vainionpaa, Jaakko Hannes; Leung, Ka Ngo; Kwan, Joe W.; Levinton, Fred

    2007-01-01

    At the Lawrence Berkeley National Laboratory (LBNL) a diagnostic neutral beam injection system for measuring plasma parameters, flow velocity, and local magnetic field is being developed. High proton fraction and small divergence is essential for diagnostic neutral beams. In our design, a neutral hydrogen beam with an 8 cm x 11 cm (or smaller) elliptical beam spot at 2.5 m from the end of the extraction column is produced. The beam will deliver up to 5 A of hydrogen beam to the target with a pulse width of ∼1 s, once every 1-2 min. The H1+ ion species of the hydrogen beam will be over 90 percent. For this application, we have compared two types of RF driven multicusp ion sources operating at 13.56MHz. The first one is an ion source with an external spiral antenna behind a dielectric RF-window. The second one uses an internal antenna in similar ion source geometry. The source needs to generate uniform plasma over a large (8 cm x 5 cm) extraction area. We expect that the ion source with internal antenna will be more efficient at producing the desired plasma density but might have the issue of limited antenna lifetime, depending on the duty factor. For both approaches there is a need for extra shielding to protect the dielectric materials from the backstreaming electrons. The source walls will be made of insulator material such as quartz that has been observed to generate plasma with higher atomic fraction than sources with metal walls. The ion beam will be extracted and accelerated by a set of grids with slits, thus forming an array of 6 sheet-shaped beamlets. The multiple grid extraction will be optimized using computer simulation programs. Neutralization of the beam will be done in neutralization chamber, which has over 70 percent neutralization efficiency

  11. Large area ion and plasma beam sources

    Energy Technology Data Exchange (ETDEWEB)

    Waldorf, J. [IPT Ionen- und Plasmatech. GmbH, Kaiserslautern (Germany)

    1996-06-01

    In the past a number of ion beam sources utilizing different methods for plasma excitation have been developed. Nevertheless, a widespread use in industrial applications has not happened, since the sources were often not able to fulfill specific demands like: broad homogeneous ion beams, compatibility with reactive gases, low ion energies at high ion current densities or electrical neutrality of the beam. Our contribution wants to demonstrate technical capabilities of rf ion and plasma beam sources, which can overcome the above mentioned disadvantages. The physical principles and features of respective sources are presented. We report on effective low pressure plasma excitation by electron cyclotron wave resonance (ECWR) for the generation of dense homogeneous plasmas and the rf plasma beam extraction method for the generation of broad low energy plasma beams. Some applications like direct plasma beam deposition of a-C:H and ion beam assisted deposition of Al and Cu with tailored thin film properties are discussed. (orig.).

  12. Large area ion and plasma beam sources

    International Nuclear Information System (INIS)

    Waldorf, J.

    1996-01-01

    In the past a number of ion beam sources utilizing different methods for plasma excitation have been developed. Nevertheless, a widespread use in industrial applications has not happened, since the sources were often not able to fulfill specific demands like: broad homogeneous ion beams, compatibility with reactive gases, low ion energies at high ion current densities or electrical neutrality of the beam. Our contribution wants to demonstrate technical capabilities of rf ion and plasma beam sources, which can overcome the above mentioned disadvantages. The physical principles and features of respective sources are presented. We report on effective low pressure plasma excitation by electron cyclotron wave resonance (ECWR) for the generation of dense homogeneous plasmas and the rf plasma beam extraction method for the generation of broad low energy plasma beams. Some applications like direct plasma beam deposition of a-C:H and ion beam assisted deposition of Al and Cu with tailored thin film properties are discussed. (orig.)

  13. Calculation of neutral beam deposition accounting for excited states

    International Nuclear Information System (INIS)

    Gianakon, T.A.

    1992-09-01

    Large-scale neutral-beam auxillary heating of plasmas has led to new plasma operational regimes which are often dominated by fast ions injected via the absorption of an energetic beam of hydrogen neutrals. An accurate simulation of the slowing down and transport of these fast ions requires an intimate knowledge of the hydrogenic neutral deposition on each flux surface of the plasma. As a refinement to the present generation of transport codes, which base their beam deposition on ground-state reaction rates, a new set of routines, based on the excited states of hydrogen, is presented as mechanism for computing the attenuation and deposition of a beam of energetic neutrals. Additionally, the numerical formulations for the underlying atomic physics for hydrogen impacting on the constiuent plasma species is developed and compiled as a numerical database. Sample results based on this excited state model are compared with the ground-state model for simple plasma configurations

  14. Neutral-beam performance analysis using a CCD camera

    International Nuclear Information System (INIS)

    Hill, D.N.; Allen, S.L.; Pincosy, P.A.

    1986-01-01

    We have developed an optical diagnostic system suitable for characterizing the performance of energetic neutral beams. An absolutely calibrated CCD video camera is used to view the neutral beam as it passes through a relatively high pressure (10 -5 Torr) region outside the neutralizer: collisional excitation of the fast deuterium atoms produces H/sub proportional to/ emission (lambda = 6561A) that is proportional to the local atomic current density, independent of the species mix of accelerated ions over the energy range 5 to 20 keV. Digital processing of the video signal provides profile and aiming information for beam optimization. 6 refs., 3 figs

  15. 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

  16. The diagnostic neutral beam system for text

    International Nuclear Information System (INIS)

    Hammond, D.P.; Burgin, D.; Coupland, J.R.; DeVere, A.P.C.; Green, T.S.; Klein, H.H.

    1986-01-01

    The detection of highly stripped impurity ions in a Tokamak plasma by means of charge exchange with a probing neutral beam is an interesting and developing technique. Such a beam system is being designed and manufactured by the Culham Laboratory under contract to the University of Texas at Austin. The specification is for a high brightness beam of hydrogen atoms of 30-50 keV energy with a current density of 30 mA/cm/sup 2/ in the target plane. The pulse length is 100 mS, and the beam has to be capable of being modulated at high frequency (≥ 1 KHz) to improve the overall detection capability of the diagnostic system. The total extracted current at 50 KV is 7.2A. The design has been based on a ''bucket'' type plasma source with a four-electrode extraction array of circular apertures. Low perveance extraction is used to obtain both high brightness and freedom from high voltage breakdown, in view of the high degree of reliability needed. Details of performance of the beam line measured during commissioning tests at Culham are given

  17. Neutralization of H- beams by magnetic stripping

    International Nuclear Information System (INIS)

    Jason, A.J.; Hudgings, D.W.; van Dyck, O.B.

    1981-01-01

    The stability of H - beams passing through strong magnetic fields has been relevant to accelerator transport problems and, recently, to neutral beam preparation techniques. The H - electron detachment rate was measured as a function of rest-frame electric field and provides parameters for a theoretical lifetime expression. The limitations imposed on H - transport by magnetic stripping, and neutral-beam preparation in emittance growth, magnetic fields, and beam energies are discussed. Application techniques are also briefly discussed

  18. Temporal behavior of neutral particle fluxes in TFTR (Tokamak Fusion Test Reactor) neutral beam injectors

    Energy Technology Data Exchange (ETDEWEB)

    Kamperschroer, J.H.; Gammel, G.M.; Roquemore, A.L.; Grisham, L.R.; Kugel, H.W.; Medley, S.S.; O' Connor, T.E.; Stevenson, T.N.; von Halle, A.; Williams, M.D.

    1989-09-01

    Data from an E {parallel} B charge exchange neutral analyzer (CENA), which views down the axis of a neutral beamline through an aperture in the target chamber calorimeter of the TFTR neutral beam test facility, exhibit two curious effects. First, there is a turn-on transient lasting tens of milliseconds having a magnitude up to three times that of the steady-state level. Second, there is a 720 Hz, up to 20% peak-to-peak fluctuation persisting the entire pulse duration. The turn-on transient occurs as the neutralizer/ion source system reaches a new pressure equilibrium following the effective ion source gas throughput reduction by particle removal as ion beam. Widths of the transient are a function of the gas throughput into the ion source, decreasing as the gas supply rate is reduced. Heating of the neutalizer gas by the beam is assumed responsible, with gas temperature increasing as gas supply rate is decreased. At low gas supply rates, the transient is primarliy due to dynamic changes in the neutralizer line density and/or beam species composition. Light emission from the drift duct corroborate the CENA data. At high gas supply rates, dynamic changes in component divergence and/or spatial profiles of the source plasma are necessary to explain the observations. The 720 Hz fluctuation is attributed to a 3% peak-to-peak ripple of 720 Hz on the arc power supply amplified by the quadratic relationship between beam divergence and beam current. Tight collimation by CENA apertures cause it to accept a very small part of the ion source's velocity space, producing a signal linearly proportional to beam divergence. Estimated fluctuations in the peak power density delivered to the plasma under these conditions are a modest 3--8% peak to peak. The efffects of both phenomena on the injected neutral beam can be ameliorated by careful operion of the ion sources. 21 refs., 11 figs., 2 tabs.

  19. Temporal behavior of neutral particle fluxes in TFTR [Tokamak Fusion Test Reactor] neutral beam injectors

    International Nuclear Information System (INIS)

    Kamperschroer, J.H.; Gammel, G.M.; Roquemore, A.L.

    1989-09-01

    Data from an E parallel B charge exchange neutral analyzer (CENA), which views down the axis of a neutral beamline through an aperture in the target chamber calorimeter of the TFTR neutral beam test facility, exhibit two curious effects. First, there is a turn-on transient lasting tens of milliseconds having a magnitude up to three times that of the steady-state level. Second, there is a 720 Hz, up to 20% peak-to-peak fluctuation persisting the entire pulse duration. The turn-on transient occurs as the neutralizer/ion source system reaches a new pressure equilibrium following the effective ion source gas throughput reduction by particle removal as ion beam. Widths of the transient are a function of the gas throughput into the ion source, decreasing as the gas supply rate is reduced. Heating of the neutalizer gas by the beam is assumed responsible, with gas temperature increasing as gas supply rate is decreased. At low gas supply rates, the transient is primarliy due to dynamic changes in the neutralizer line density and/or beam species composition. Light emission from the drift duct corroborate the CENA data. At high gas supply rates, dynamic changes in component divergence and/or spatial profiles of the source plasma are necessary to explain the observations. The 720 Hz fluctuation is attributed to a 3% peak-to-peak ripple of 720 Hz on the arc power supply amplified by the quadratic relationship between beam divergence and beam current. Tight collimation by CENA apertures cause it to accept a very small part of the ion source's velocity space, producing a signal linearly proportional to beam divergence. Estimated fluctuations in the peak power density delivered to the plasma under these conditions are a modest 3--8% peak to peak. The efffects of both phenomena on the injected neutral beam can be ameliorated by careful operion of the ion sources. 21 refs., 11 figs., 2 tabs

  20. Power and gas flow models for monoenergetic neutral beam injectors

    International Nuclear Information System (INIS)

    Fasolo, J.A.

    1978-01-01

    Large, ignition tokamak reactors (ITR, EPR, and beyond will require supplemental heating to achieve ignition. In the earlier machines, at least, this heating will probably be provided by monoenergetic neutral beams. These beams, with energies greater than or equal to 150 keV, will most likely be derived from D + or D - ions produced by direct extraction ion sources. A positive ion source will be followed by a bending magnet, a neutralizer, and a second bending magnet. The first magnet will remove molecular ions, and the second one atomic ions. Direct convertors will be used to recover energy from unused molecular and atomic ions. The first bending magnet may be omitted if D - ion sources are used. Models have been developed for power and gas flow in injectors which employ direct extraction D + or D - ion sources. The power flow model accounts explicitly for all beam losses in terms of line densities of gas along paths traversed by ions and neutrals and cross sections for dissociation and charge-changing collisions. The gas flow model uses the results of power flow calculations and known gas flows from sources and neutralizers to determine gas loads and pumping requirements in various parts of the injector

  1. ALCBEAM - Neutral beam formation and propagation code for beam-based plasma diagnostics

    Science.gov (United States)

    Bespamyatnov, I. O.; Rowan, W. L.; Liao, K. T.

    2012-03-01

    ALCBEAM is a new three-dimensional neutral beam formation and propagation code. It was developed to support the beam-based diagnostics installed on the Alcator C-Mod tokamak. The purpose of the code is to provide reliable estimates of the local beam equilibrium parameters: such as beam energy fractions, density profiles and excitation populations. The code effectively unifies the ion beam formation, extraction and neutralization processes with beam attenuation and excitation in plasma and neutral gas and beam stopping by the beam apertures. This paper describes the physical processes interpreted and utilized by the code, along with exploited computational methods. The description is concluded by an example simulation of beam penetration into plasma of Alcator C-Mod. The code is successfully being used in Alcator C-Mod tokamak and expected to be valuable in the support of beam-based diagnostics in most other tokamak environments. Program summaryProgram title: ALCBEAM Catalogue identifier: AEKU_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEKU_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 66 459 No. of bytes in distributed program, including test data, etc.: 7 841 051 Distribution format: tar.gz Programming language: IDL Computer: Workstation, PC Operating system: Linux RAM: 1 GB Classification: 19.2 Nature of problem: Neutral beams are commonly used to heat and/or diagnose high-temperature magnetically-confined laboratory plasmas. An accurate neutral beam characterization is required for beam-based measurements of plasma properties. Beam parameters such as density distribution, energy composition, and atomic excited populations of the beam atoms need to be known. Solution method: A neutral beam is initially formed as an ion beam which is extracted from

  2. Scattering of ion beams from surfaces

    International Nuclear Information System (INIS)

    Heiland, W.; Taglauer, E.

    1978-01-01

    A review is presented of the scattering of ion beams from surfaces and the physical phenomena which are probably most important for the formation of the final state (charge and excitation) of the secondary particles. The subject is treated under the headings: ion scattering, desorption by ion impact, and neutralization. (U.K.)

  3. Transient Enhancement ('Spike-on-Tail') Observed on Neutral-Beam-Injected Energetic Ion Spectra Using the E||B Neutral Particle Analyzer in the National Spherical Torus Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Medley, S. S. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Gorelenkov, N. N. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Bell, R. E. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Fredrickson, E. D. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Gerhardt, S. P. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); LeBlanc, B. P. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Podesta, M. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Roquemore, A. L. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

    2010-06-01

    An increase of up to four-fold in the E||B Neutral Particle Analyzer (NPA) charge exchange neutral flux localized at the Neutral Beam (NB) injection full energy is observed in the National Spherical Torus Experiment (NSTX). Termed the High-Energy Feature (HEF), it appears on the NB-injected energetic ion spectrum only in discharges where tearing or kink-type modes (f < 10 kHz) are absent, TAE activity (f ~ 10-150 kHz) is weak (δBrms < 75 mGauss) and CAE/GAE activity (f ~ 400 – 1200 kHz) is robust. The feature exhibits a growth time of ~ 20 - 80 ms and occasionally develops a slowing down distribution that continues to evolve over periods of 100's of milliseconds, a time scale long compared with the typical ~ 10's ms equilibration time of the NB injected particles. The HEF is observed only in H-mode (not L-mode) discharges with injected NB power of 4 MW or greater and in the field pitch range v||/v ~ 0.7 – 0.9; i.e. only for passing (never trapped) energetic ions. The HEF is suppressed by vessel conditioning using lithium deposition at rates ~ 100 mg/shot, a level sufficient to suppress ELM activity. Increases of ~ 10 - 30 % in the measured neutron yield and total stored energy are observed to coincide with the feature along with broadening of measured Te(r), Ti(r) and ne(r) profiles. However, TRANSP analysis shows that such increases are driven by plasma profile changes and not the HEF phenomenon itself. Though a definitive mechanism has yet to be developed, the HEF appears to be caused by a form of TAE/CAE wave-particle interaction that distorts of the NB fast ion distribution in phase space.

  4. Energy recovery in high energy neutral beam injectors

    International Nuclear Information System (INIS)

    Laffite, S.

    1991-07-01

    One way to heat the plasma of thermonuclear fusion experiments, is to inject high energy (50 to 100 KeV per nucleon), neutral particles (hydrogen or deuterium). Neutral beam elaboration consists in ion production and acceleration, neutralisation by charge exchange on gas target, disposal of unneutralized ions. But, in the case of positive ion based neutral beam injection, the neutralisation efficiency is limited to 50% at 100 KeV, and decreases rapidly with energy. The energy recovery is a new method for disposing of the unneutralized ions: these are electrostatically decelerated and collected on electrodes which are polarized at low voltage, close to the ion source potential. An energy recovery system was studied and experimented with positive ion beams of 50 and 100 KeV. In the framework of a french-japanese collaboration, we measured a relative power reduction of about 20%, with 100 KeV, 1,5 MW deuterium beams. We have also studied theoretically an energy recovery system for negative ion beams, which will be utilized at high energy (1 MeV). A relative power reduction of 20% can be expected in the best conditions [fr

  5. Neutral beam injection system design for KSTAR tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Choi, B.H.; Lee, K.W.; Chung, K.S.; Oh, B.H.; Cho, Y.S.; Bae, Y.D.; Han, J.M. [Korea Atomic Energy Research Institute, Taejon (Korea)

    1998-06-01

    The NBI system for KSTAR (Korean Superconducting Tokamak Advanced Research) has been designed based on conventional positive ion beam technology. One beam line consists of three ion sources, three neutralizers, one bending magnet, and one drift tube. This system will deliver 8 MW deuterium beam to KSTAR plasma in normal operation to support the advanced experiments on heating, current drive and profile control. The key technical issues in this design were high power ion source(120 kV, 65 A), long pulse operation (300 seconds; world record is 30 sec), and beam rotation from vertical to horizontal direction. The suggested important R and D points on ion source and beam line components are also included. (author). 7 refs., 27 figs., 1 tab.

  6. Validation of fast-ion D-alpha spectrum measurements during EAST neutral-beam heated plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Huang, J., E-mail: juan.huang@ipp.ac.cn; Wu, C. R.; Hou, Y. M.; Chang, J. F.; Ding, S. Y.; Chen, Y. J.; Jin, Z.; Xu, Z.; Gao, W.; Wang, J. F.; Lyu, B.; Zang, Q.; Zhong, G. Q.; Hu, L.; Wan, B. [Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, 230031 Hefei, Anhui (China); Heidbrink, W. W.; Stagner, L.; Zhu, Y. B. [University of California, Irvine, California 92697 (United States); Hellermann, M. G. von [Diagnostic Team, ITER Organization, Route de Vinon-sur-Verdon 13067 St. Paul Lez Durance (France)

    2016-11-15

    To investigate the fast ion behavior, a fast ion D-alpha (FIDA) diagnostic system has been installed on EAST. Fast ion features can be inferred from the Doppler shifted spectrum of Balmer-alpha light from energetic hydrogenic atoms. This paper will focus on the validation of FIDA measurements performed using MHD-quiescent discharges in 2015 campaign. Two codes have been applied to calculate the D{sub α} spectrum: one is a Monte Carlo code, Fortran 90 version FIDASIM, and the other is an analytical code, Simulation of Spectra (SOS). The predicted SOS fast-ion spectrum agrees well with the measurement; however, the level of fast-ion part from FIDASIM is lower. The discrepancy is possibly due to the difference between FIDASIM and SOS velocity distribution function. The details will be presented in the paper to primarily address comparisons of predicted and observed spectrum shapes/amplitudes.

  7. Ion-beam technologies

    Energy Technology Data Exchange (ETDEWEB)

    Fenske, G.R. [Argonne National Lab., IL (United States)

    1993-01-01

    This compilation of figures and diagrams reviews processes for depositing diamond/diamond-like carbon films. Processes addressed are chemical vapor deposition (HFCVD, PACVD, etc.), plasma vapor deposition (plasma sputtering, ion beam sputtering, evaporation, etc.), low-energy ion implantation, and hybrid processes (biased sputtering, IBAD, biased HFCVD, etc.). The tribological performance of coatings produced by different means is discussed.

  8. Ion beam studies

    International Nuclear Information System (INIS)

    Freeman, J.H.; Chivers, D.J.; Gard, G.A.; Temple, W.

    1977-04-01

    A description of techniques for the production of intense beams of heavy ions is given. A table of recommended operational procedures for most elements is included. The ionisation of boron is considered in some detail because of its particular importance as a dopant for ion implantation. (author)

  9. Neutral-beam-heating applications and development

    International Nuclear Information System (INIS)

    Menon, M.M.

    1981-01-01

    The technique of heating the plasma in magnetically confined fusion devices by the injection of intense beams of neutral atoms is described. The basic principles governing the physics of neutral beam heating and considerations involved in determining the injection energy, power, and pulse length required for a fusion reactor are discussed. The pertinent experimental results from various fusion devices are surveyed to illustrate the efficacy of this technique. The second part of the paper is devoted to the technology of producing the neutral beams. A state-of-the-art account o the development of neutral injectors is presented, and the prospects for utilizing neutral injection to heat the plasma in a fusion reactor are examined

  10. Ion optics study in a single-beamlet system for the 160-keV Joint European Torus neutral beam injectors

    International Nuclear Information System (INIS)

    Bottiglioni, F.; Bussac, J.P.; Jequier, F.

    1986-01-01

    The optics of the 160-keV deuterium neutral beam injection for the Joint European Torus--plug-in neutral injector (JET-PINI) have been studied in a single beamlet, using the test stand ligne d'etudes d'optiques (LEO). The beamlet optical features, that is perveance-divergence relationships, beam profiles, and steering angle by aperture offset, have been measured. Computations have been compared with the experimental results obtained both in this monobeamlet experiment and in the multibeamlet system of the 160-keV PINI injector

  11. Ion optics study in a single-beamlet system for the 160-keV Joint European Torus neutral beam injectors

    Energy Technology Data Exchange (ETDEWEB)

    Bottiglioni, F.; Bussac, J.P.; Jequier, F.

    1986-09-01

    The optics of the 160-keV deuterium neutral beam injection for the Joint European Torus--plug-in neutral injector (JET-PINI) have been studied in a single beamlet, using the test stand ligne d'etudes d'optiques (LEO). The beamlet optical features, that is perveance-divergence relationships, beam profiles, and steering angle by aperture offset, have been measured. Computations have been compared with the experimental results obtained both in this monobeamlet experiment and in the multibeamlet system of the 160-keV PINI injector.

  12. Ion Accelerator Merges Several Beams

    Science.gov (United States)

    Aston, G.

    1984-01-01

    Intense ion beam formed by merging multiple ion beamlets into one concentrated beam. Beamlet holes in graphite screen and focusing grids arranged in hexagonal pattern. Merged beam passes through single hole in each of aluminum accelerator and decelerator grids. Ion extraction efficiency, beam intensity, and focusing improved.

  13. Computerized operation of the DIII-D neutral beams

    International Nuclear Information System (INIS)

    Glad, A.S.; Tooker, J.F.

    1986-01-01

    Operation of the DIII-D neutral beams utilizes computerized control to provide routine tokamak beam heating shots and an effective method for automatic ion source operation. Computerized control reduces operational complexity, thus providing consistent reliability and availability of beams and a significant reduction in the the costs of routine operation. The objectives in implementing computerized control for operation were: (1) to improve operator efficiency for controlling multiple beam lines and increasing beam availability through standard procedures, (2) to provide a simplified scheme that operators and coordinators can construct and maintain, and (3) to provide a single integrated mechanism for both tokamak operation and automatic source conditioning. The years of experience in operating neutral beams at Doublet III provided the data necessary to meet the objectives. The method for computerized control consisted of three integrated functions: (1) a structured command language was implemented to provide the mechanism for automatically sequencing beams, (2) a historical file was constructed from the operational parameters to characterize the ion source, and consists of data from approximately 100,000 beam shots, and (3) procedures were developed integrating the language to the historical file for normal operation and source conditioning. This paper describes the method for sequencing beams automatically, the structure of the historical data file, and the procedures which integrate the historical data with tokamak operation and automatic source conditioning

  14. Study on space charge compensation in negative hydrogen ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, A. L.; Chen, J. E. [University of Chinese Academy of Sciences, Beijing 100049 (China); State Key Laboratory of Nuclear Physics and Technology, Institute of Heavy Ion Physics, School of Physics, Peking University, Beijing 100871 (China); Peng, S. X., E-mail: sxpeng@pku.edu.cn; Ren, H. T.; Zhang, T.; Zhang, J. F.; Xu, Y.; Guo, Z. Y. [State Key Laboratory of Nuclear Physics and Technology, Institute of Heavy Ion Physics, School of Physics, Peking University, Beijing 100871 (China)

    2016-02-15

    Negative hydrogen ion beam can be compensated by the trapping of ions into the beam potential. When the beam propagates through a neutral gas, these ions arise due to gas ionization by the beam ions. However, the high neutral gas pressure may cause serious negative hydrogen ion beam loss, while low neutral gas pressure may lead to ion-ion instability and decompensation. To better understand the space charge compensation processes within a negative hydrogen beam, experimental study and numerical simulation were carried out at Peking University (PKU). The simulation code for negative hydrogen ion beam is improved from a 2D particle-in-cell-Monte Carlo collision code which has been successfully applied to H{sup +} beam compensated with Ar gas. Impacts among ions, electrons, and neutral gases in negative hydrogen beam compensation processes are carefully treated. The results of the beam simulations were compared with current and emittance measurements of an H{sup −} beam from a 2.45 GHz microwave driven H{sup −} ion source in PKU. Compensation gas was injected directly into the beam transport region to modify the space charge compensation degree. The experimental results were in good agreement with the simulation results.

  15. Beam profile effects on NPB [neutral particle beam] performance

    International Nuclear Information System (INIS)

    LeClaire, R.J. Jr.

    1988-03-01

    A comparison of neutral particle beam brightness for various neutral beam profiles indicates that the widely used assumption of a Gaussian profile may be misleading for collisional neutralizers. An analysis of available experimental evidence shows that lower peaks and higher tails, compared to a Gaussian beam profile, are observed out of collisional neutralizers, which implies that peak brightness is over estimated, and for a given NPB platform-to-target range, the beam current (power), dwell time or some combination of such engagement parameters would have to be altered to maintain a fixed dose on target. Based on the present analysis, this factor is nominally about 2.4 but may actually be as low as 1.8 or as high as 8. This is an important consideration in estimating NPB constellation performance in SDI engagement contexts. 2 refs., 6 figs

  16. Neutral-beam-injected tokamak fusion reactors: a review

    International Nuclear Information System (INIS)

    Jassby, D.L.

    1976-08-01

    The theories of energetic-ion velocity distributions, stability, injection, and orbits were summarized. The many-faceted role of the energetic ions in plasma heating, fueling, and current maintenance, as well as in the direct enhancement of fusion power multiplication and power density, is discussed in detail for three reactor types. The relevant implications of recent experimental results on several beam-injected tokamaks are examined. The behavior of energetic ions is found to be in accordance with classical theory, large total ion energy densities are readily achieved, and plasma equilibrium and stability are maintained. The status of neutral-beam injectors and of conceptual design studies of beam-driven reactors are briefly reviewed. The principal plasma-engineering problems are those associated directly with achieving quasi-stationary operation

  17. A high energy neutral beam system for reactors

    International Nuclear Information System (INIS)

    Anderson, O.A.; Chan, C.F.; Cooper, W.S.

    1988-09-01

    High energy neutral beams provide a promising method of heating and driving current in steady-state tokamak fusion reactors. As an example, we have made a conceptual design of a neutral beam system for current drive on the International Thermonuclear Experimental Reactor (ITER). The system, based on electrostatic acceleration of D/sup /minus// ions, can deliver up to 100 MW of 1.6 MeV D 0 neutrals through three ports. Radiation protection is provided by locating sensitive beamline components 35 to 50 m from the reactor. In an application to a 3300 MW power reactor, a system delivering 120 MW of 2-2.4 MeV deuterium beams assisted by 21 MW of lower hybrid wave power drives 25 MA and provides an adequate plasma power gain (Q = 24) for a commercial fusion power plant. 8 refs., 1 fig., 2 tabs

  18. Experimental approach to high power long duration neutral beams

    International Nuclear Information System (INIS)

    Horiike, Hiroshi

    1981-12-01

    Experimental studies of ion sources and beam dumps for the development of a high power long duration neutral beam injector for JT-60 are presented. Long pulse operation of high power beams requires a high degree of reliability. To develop a reliable ion source with large extraction area, a new duoPIGatron ion source with a coaxially shaped intermediate electrode is proposed and tested. Magnetic configuration is examined numerically to obtain high current arc discharge and source plasma with small density variation. Experimental results show that primary electrons were fed widely from the cathode plasma region to the source plasma region and that dense uniform source plasma could be obtained easily. Source plasma characteristics are studied and comparison of these with other sources are also described. To develop extraction electrode of high power ion source, experimental studies were made on the cooling of the electrode. Long Pulse beams were extracted safely under the condition of high heat loading on the electrode. Finally, burnout study for the development of high power beam dumps is presented. Burnout data were obtained from subcooled forced-convective boiling of water in a copper finned tube irradiated by high power ion beams. The results yield simple burnout correlations which can be used for the prediction of burnout heat flux of the beam dump. (author)

  19. 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

  20. Measurement of beam energy spectrum and impurity content in high-power neutral beam injectors

    International Nuclear Information System (INIS)

    Langley, R.A.; Ryan, P.M.; Tsai, C.C.; Menon, M.M.; Botnick, E.M.; Magee, C.W.

    1985-01-01

    The energy spectrum and impurity content of a high-power neutral beam are measured by implanting the beam into high-purity silicon crystals. The depth distribution of the beam particles is then measured by secondary ion mass spectrometry (SIMS); the penetration depth is a function of the incident particle energy. This is one of the few measurement techniques that can determine neutral beam energy components directly. From the results, percentages of atomic and molecular ions in the source plasma can be inferred. Use of deuterium as the source gas provides insight into the role of residual hydrogen in the ion source and accelerating grids and in the SIMS analysis. The principal impurities are carbon and oxygen. Preliminary data indicate that carbon can originate from both methane and carbon monoxide, while oxygen can come from molecular oxygen, carbon monoxide, and water. Results are given and future plans are discussed

  1. Effect of thermal neutrals on the impurity ion radiation

    International Nuclear Information System (INIS)

    Zhidkov, A.G.; Lysenko, S.E.

    1982-01-01

    Effect of thermal neutrals (deuterium) on radiation of C and O light impurities for T-15 device is investigated. It is shown on the basis of numerical solution of equations of balance and kinetic equation of thermal neutral transfer that in case of injection of fast neutrals into plasma the concentration of thermal neutrals exceeds considerably the concentration of injected neutrals. This results in additional growth of radiation losses 2-6 times. Effect of injection on ionization balance of ions and radiation losses of plasma when increasing energy of injected neutrals is considered. Problem of advisability of increasing energy of injected neutrals requires combined consideration both of effect of injection on radiation losses of plasma and growth of energy losses during production of beams of higher energies from the view-point of reactor energy balance as a whole

  2. Intense non-relativistic cesium ion beam

    International Nuclear Information System (INIS)

    Lampel, M.C.

    1984-02-01

    The Heavy Ion Fusion group at Lawrence Berkeley Laboratory has constructed the One Ampere Cesium Injector as a proof of principle source to supply an induction linac with a high charge density and high brightness ion beam. This is studied here. An electron beam probe was developed as the major diagnostic tool for characterizing ion beam space charge. Electron beam probe data inversion is accomplished with the EBEAM code and a parametrically adjusted model radial charge distribution. The longitudinal charge distribution was not derived, although it is possible to do so. The radial charge distribution that is derived reveals an unexpected halo of trapped electrons surrounding the ion beam. A charge fluid theory of the effect of finite electron temperature on the focusing of neutralized ion beams (Nucl. Fus. 21, 529 (1981)) is applied to the problem of the Cesium beam final focus at the end of the injector. It is shown that the theory's predictions and assumptions are consistent with the experimental data, and that it accounts for the observed ion beam radius of approx. 5 cm, and the electron halo, including the determination of an electron Debye length of approx. 10 cm

  3. Engineering problems of future neutral beam injectors

    International Nuclear Information System (INIS)

    Fink, J.

    1977-01-01

    Because there is no limit to the energy or power that can be delivered by a neutral-beam injector, its use will be restricted by either its cost, size, or reliability. Studies show that these factors can be improved by the injector design, and several examples, taken from mirror reactor studies, are given

  4. Experimental database and design concept for a 1-MW, 200-keV neutral-beam line based on a SITEX negative ion source

    International Nuclear Information System (INIS)

    Dagenhart, W.K.; Gardner, W.L.; Stirling, W.L.; Whealton, J.H.

    1983-01-01

    Scaling studies for a SITEX negative ion source to produce 200-keV, 10-A, long pulse D - beams are under way at Oak Ridge National Laboratory (ORNL). Designs have been restricted to the use of established techniques and reasonably well-demonstrated scaling. The results show that the 1-A SITEX source can be directly scaled to produce 200-keV, 10-A long pulse ion beams with a source power efficiency of less than or equal to 5 kW of total plasma generator power per ampere of D - beam generated. Extracted electron-to-D - ratios should be less than or equal to 0.06, with all extracted electrons recovered at less than or equal to 10% of the first gap potential energy difference. The close-coupled accelerating structure will be 5 cm long and have five electrodes with 21 slits each, with a 50-kV/cm field in each gap

  5. Particle reflection and TFTR neutral beam diagnostics

    International Nuclear Information System (INIS)

    Kamperschroer, J.H.; Grisham, L.R.; Kugel, H.W.; O'Connor, T.E.; Newman, R.A.; Stevenson, T.N.; von Halle, A.; Williams, M.D.

    1992-04-01

    Determination of two critical neutral beam parameters, power and divergence, are affected by the reflection of a fraction of the incident energy from the surface of the measuring calorimeter. On the TFTR Neutral Beam Test Stand, greater than 30% of the incident power directed at the target chamber calorimeter was unaccounted for. Most of this loss is believed due to reflection from the surface of the flat calorimeter, which was struck at a near grazing incidence (12 degrees). Beamline calorimeters, of a ''V''-shape design, while retaining the beam power, also suffer from reflection effects. Reflection, in this latter case, artificially peaks the power toward the apex of the ''V'', complicating the fitting technique, and increasing the power density on axis by 10 to 20%; an effect of import to future beamline designers. Agreement is found between measured and expected divergence values, even with 24% of the incident energy reflected

  6. Particle reflection and TFTR neutral beam diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Kamperschroer, J.H.; Grisham, L.R.; Kugel, H.W.; O`Connor, T.E.; Newman, R.A.; Stevenson, T.N.; von Halle, A.; Williams, M.D.

    1992-04-01

    Determination of two critical neutral beam parameters, power and divergence, are affected by the reflection of a fraction of the incident energy from the surface of the measuring calorimeter. On the TFTR Neutral Beam Test Stand, greater than 30% of the incident power directed at the target chamber calorimeter was unaccounted for. Most of this loss is believed due to reflection from the surface of the flat calorimeter, which was struck at a near grazing incidence (12{degrees}). Beamline calorimeters, of a ``V``-shape design, while retaining the beam power, also suffer from reflection effects. Reflection, in this latter case, artificially peaks the power toward the apex of the ``V``, complicating the fitting technique, and increasing the power density on axis by 10 to 20%; an effect of import to future beamline designers. Agreement is found between measured and expected divergence values, even with 24% of the incident energy reflected.

  7. Particle reflection and TFTR neutral beam diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Kamperschroer, J.H.; Grisham, L.R.; Kugel, H.W.; O' Connor, T.E.; Newman, R.A.; Stevenson, T.N.; von Halle, A.; Williams, M.D.

    1992-04-01

    Determination of two critical neutral beam parameters, power and divergence, are affected by the reflection of a fraction of the incident energy from the surface of the measuring calorimeter. On the TFTR Neutral Beam Test Stand, greater than 30% of the incident power directed at the target chamber calorimeter was unaccounted for. Most of this loss is believed due to reflection from the surface of the flat calorimeter, which was struck at a near grazing incidence (12{degrees}). Beamline calorimeters, of a V''-shape design, while retaining the beam power, also suffer from reflection effects. Reflection, in this latter case, artificially peaks the power toward the apex of the V'', complicating the fitting technique, and increasing the power density on axis by 10 to 20%; an effect of import to future beamline designers. Agreement is found between measured and expected divergence values, even with 24% of the incident energy reflected.

  8. First neutral beam injection experiments on KSTAR tokamak.

    Science.gov (United States)

    Jeong, S H; Chang, D H; Kim, T S; In, S R; Lee, K W; Jin, J T; Chang, D S; Oh, B H; Bae, Y S; Kim, J S; Park, H T; Watanabe, K; Inoue, T; Kashiwagi, M; Dairaku, M; Tobari, H; Hanada, M

    2012-02-01

    The first neutral beam (NB) injection system of the Korea Superconducting Tokamak Advanced Research (KSTAR) tokamak was partially completed in 2010 with only 1∕3 of its full design capability, and NB heating experiments were carried out during the 2010 KSTAR operation campaign. The ion source is composed of a JAEA bucket plasma generator and a KAERI large multi-aperture accelerator assembly, which is designed to deliver a 1.5 MW, NB power of deuterium at 95 keV. Before the beam injection experiments, discharge, and beam extraction characteristics of the ion source were investigated. The ion source has good beam optics in a broad range of beam perveance. The optimum perveance is 1.1-1.3 μP, and the minimum beam divergence angle measured by the Doppler shift spectroscopy is 0.8°. The ion species ratio is D(+):D(2)(+):D(3)(+) = 75:20:5 at beam current density of 85 mA/cm(2). The arc efficiency is more than 1.0 A∕kW. In the 2010 KSTAR campaign, a deuterium NB power of 0.7-1.5 MW was successfully injected into the KSTAR plasma with a beam energy of 70-90 keV. L-H transitions were observed within a wide range of beam powers relative to a threshold value. The edge pedestal formation in the T(i) and T(e) profiles was verified through CES and electron cyclotron emission diagnostics. In every deuterium NB injection, a burst of D-D neutrons was recorded, and increases in the ion temperature and plasma stored energy were found.

  9. First neutral beam injection experiments on KSTAR tokamaka)

    Science.gov (United States)

    Jeong, S. H.; Chang, D. H.; Kim, T. S.; In, S. R.; Lee, K. W.; Jin, J. T.; Chang, D. S.; Oh, B. H.; Bae, Y. S.; Kim, J. S.; Park, H. T.; Watanabe, K.; Inoue, T.; Kashiwagi, M.; Dairaku, M.; Tobari, H.; Hanada, M.

    2012-02-01

    The first neutral beam (NB) injection system of the Korea Superconducting Tokamak Advanced Research (KSTAR) tokamak was partially completed in 2010 with only 1/3 of its full design capability, and NB heating experiments were carried out during the 2010 KSTAR operation campaign. The ion source is composed of a JAEA bucket plasma generator and a KAERI large multi-aperture accelerator assembly, which is designed to deliver a 1.5 MW, NB power of deuterium at 95 keV. Before the beam injection experiments, discharge, and beam extraction characteristics of the ion source were investigated. The ion source has good beam optics in a broad range of beam perveance. The optimum perveance is 1.1-1.3 μP, and the minimum beam divergence angle measured by the Doppler shift spectroscopy is 0.8°. The ion species ratio is D+:D2+:D3+ = 75:20:5 at beam current density of 85 mA/cm2. The arc efficiency is more than 1.0 A/kW. In the 2010 KSTAR campaign, a deuterium NB power of 0.7-1.5 MW was successfully injected into the KSTAR plasma with a beam energy of 70-90 keV. L-H transitions were observed within a wide range of beam powers relative to a threshold value. The edge pedestal formation in the Ti and Te profiles was verified through CES and electron cyclotron emission diagnostics. In every deuterium NB injection, a burst of D-D neutrons was recorded, and increases in the ion temperature and plasma stored energy were found.

  10. Plasma-parameter measurements using neutral-particle-beam attenuation

    International Nuclear Information System (INIS)

    Foote, J.H.; Molvik, A.W.; Turner, W.C.

    1982-01-01

    Intense and energetic neutral-particle-beam injection used for fueling or heating magnetically confined, controlled-fusion experimental plasmas can also provide diagnostic measurements of the plasmas. The attenuation of an atomic beam (mainly from charge-exchange and ionization interactions) when passing through a plasma gives the plasma line density. Orthogonal arrays of highly collimated detectors of the secondary-electron-emission type have been used in magnetic-mirror experiments to measure neutral-beam attenuation along chords through the plasma volume at different radial and axial positions. The radial array is used to infer the radial plasma-density profile; the axial array, to infer the axial plasma-density profile and the ion angular distribution at the plasma midplane

  11. Oblate Field-Reversed Configuration Experiments with Neutral Beam Injection

    Science.gov (United States)

    T., II; Gi, K.; Umezawa, T.; Inomoto, M.; Ono, Y.

    2011-11-01

    The effect of energetic beam ions on oblate Field-Reversed Configurations (FRCs) has been studied experimentally in the TS-4 plasma merging device. In order to examine its kinetic effects, we developed an economical pulsed Neutral Beam Injection (NBI) system by using a washer gun plasma source and finally attained the beam power of 0.6 MW (15 kV, 40 A) for its pulse length of 0.5 ms, longer than the FRC lifetime in TS-4. The Monte Carlo simulation indicates that the tangential NB ions of 15 keV are trapped between the magnetic axis and the separatrix. We found that two merging high-s (s is plasma size normalized by ion gyroradius) hydrogen spheromaks with opposite helicities relaxed into the large scale FRC with poloidal flux as high as 15 mWb under the assistance of the NBI. Without the assistance of NBI, however, they did not relax to an FRC but to another spheromak. These facts suggest some ion kinetic effects such as toroidal ion flow are essential to FRC stability. Recently, two new NB sources with acceleration voltage and current of 15 kV and 20 A were installed on the TS-4 device on the midplane for tangential injection, increasing the beam power over 1 MW. We will start the upgraded FRC experiments using the 1 MW NBI for ion flow control.

  12. Powerful 160-keV neutral deuterium beam injector for application in fusion research

    Energy Technology Data Exchange (ETDEWEB)

    Fumelli, M.; Bayetti, P.; Becherer, R.; Bottiglioni, F.; Desmons, M.; Jequier, F.; Pamela, J.; Raimbault, P.; Valckx, F.P.G.

    1986-07-01

    A 160-keV neutral deuterium beam injector has been developed for plasma heating in JET (Joint European Torus) fusion experiment. This injector has been reliably operated at 5.9-MW extracted deuterium ion beam power (37-A, 160-keV ion beam) and 5-s pulse duration. The neutral beam power was 1.75 MW corresponding to an overall neutral injector power efficiency of 30%. The beam divergence was 0.6/sup 0/. The ion beam was accelerated with a three-grid multiaperture system (aperture diameter phi = 11 mm). The accelerating gap length was 24 mm. The extracted deuterium ion current density amounted to 150 mA/cm/sup 2/. Grid and source body power loadings were acceptable for quasi-steady-state operation.

  13. Powerful 160-keV neutral deuterium beam injector for application in fusion research

    International Nuclear Information System (INIS)

    Fumelli, M.; Bayetti, P.; Becherer, R.; Bottiglioni, F.; Desmons, M.; Jequier, F.; Pamela, J.; Raimbault, P.; Valckx, F.P.G.

    1986-01-01

    A 160-keV neutral deuterium beam injector has been developed for plasma heating in JET (Joint European Torus) fusion experiment. This injector has been reliably operated at 5.9-MW extracted deuterium ion beam power (37-A, 160-keV ion beam) and 5-s pulse duration. The neutral beam power was 1.75 MW corresponding to an overall neutral injector power efficiency of 30%. The beam divergence was 0.6 0 . The ion beam was accelerated with a three-grid multiaperture system (aperture diameter phi = 11 mm). The accelerating gap length was 24 mm. The extracted deuterium ion current density amounted to 150 mA/cm 2 . Grid and source body power loadings were acceptable for quasi-steady-state operation

  14. Ion Beam Extraction by Discrete Ion Focusing

    DEFF Research Database (Denmark)

    2010-01-01

    An apparatus (900) and methods are disclosed for ion beam extraction. In an implementation, the apparatus includes a plasma source (or plasma) (802) and an ion extractor (804). The plasma source is adapted to generate ions and the ion extractor is immersed in the plasma source to extract a fraction...... of the generated ions. The ion extractor is surrounded by a space charge (810) formed at least in part by the extracted ions. The ion extractor includes a biased electrode (806) forming an interface with an insulator (808). The interface is customized to form a strongly curved potential distribution (812......) in the space-charge surrounding the ion extractor. The strongly curved potential distribution focuses the extracted ions towards an opening (814) on a surface of the biased electrode thereby resulting in an ion beam....

  15. Transmission of the Neutral Beam Heating Beams at TJ-II

    International Nuclear Information System (INIS)

    Fuentes Lopez, C.

    2007-01-01

    Neutral beam injection heating has been development for the TJ-II stellarator. The beam has a port-through power between 700-1500 kW and injection energy 40 keV. The sensibility of the injection system to the changes of several parameters is analysed. Beam transmission is limited by losses processes since beam is born into the ions source until is coming into the fusion machine. For the beam transmission optimization several beam diagnostics have been developed. A carbon fiber composite (CFC) target calorimeter has been installed at TJ-II to study in situ the power density distribution of the neutral beams. The thermographic print of the beam can be recorded and analysed in a reliable way due to the highly anisotropic thermal conductivity of the target material. With the combined thermographic and calorimetric measurements it has been possible to determine the power density distribution of the beam. It has been found that a large beam halo is present, which can be explained by the extreme misalignment of the grids. This kind of halo has a deleterious effect on beam transport and must be minimized in order to improve the plasma heating capability of the beams. (Author) 155 refs

  16. Heavy ion beam probing

    Energy Technology Data Exchange (ETDEWEB)

    Hickok, R L

    1980-07-01

    This report consists of the notes distributed to the participants at the IEEE Mini-Course on Modern Plasma Diagnostics that was held in Madison, Wisconsin in May 1980. It presents an overview of Heavy Ion Beam Probing that briefly describes the principles and discuss the types of measurements that can be made. The problems associated with implementing beam probes are noted, possible variations are described, estimated costs of present day systems, and the scaling requirements for large plasma devices are presented. The final chapter illustrates typical results that have been obtained on a variety of plasma devices. No detailed calculations are included in the report, but a list of references that will provide more detailed information is included.

  17. Heavy ion beam probing

    International Nuclear Information System (INIS)

    Hickok, R.L.

    1980-07-01

    This report consists of the notes distributed to the participants at the IEEE Mini-Course on Modern Plasma Diagnostics that was held in Madison, Wisconsin in May 1980. It presents an overview of Heavy Ion Beam Probing that briefly describes the principles and discuss the types of measurements that can be made. The problems associated with implementing beam probes are noted, possible variations are described, estimated costs of present day systems, and the scaling requirements for large plasma devices are presented. The final chapter illustrates typical results that have been obtained on a variety of plasma devices. No detailed calculations are included in the report, but a list of references that will provide more detailed information is included

  18. Focused ion beam technology

    International Nuclear Information System (INIS)

    Gamo, K.

    1993-01-01

    Focussed ion beam (FIB) technology has the advantage of being a maskless process compatible with UHV processing. This makes it attractive for use in in situ processing and has been applied to the fabrication of various mesoscopic structures. The present paper reviews these results whilst putting emphasis on in situ processing by a combined FIB and molecular beam epitaxy system. The typical performance of present FIB systems is also presented. In order to utilize the potential advantages of FIB processing, reduction of damage and improvement of throughput are important, and much effort has been devoted to developing processing techniques which require a reduced dose. The importance of low-energy FIB is discussed. (author)

  19. Neutral beam injection in 2XIIB

    International Nuclear Information System (INIS)

    Hibbs, S.M.

    1975-01-01

    Integrated into the operation of the 2XIIB controlled fusion experiment is a 600-A, 20-keV neutral injection system: the highest neutral-beam current capacity of any existing fusion machine. This paper outlines the requirements of the injection system and the design features to which they led. Both mechanical and electrical aspects are discussed. Also included is a brief description of some operational aspects of the system and some of the things we have learned along the way, as well as a short history of the most significant developments

  20. The influence of grid positioning on the beam optics in the neutral beam injectors for ITER

    Energy Technology Data Exchange (ETDEWEB)

    Veltri, Pierluigi, E-mail: pierluigi.veltri@igi.cnr.it [Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Corso Stati Uniti 4, Padova (Italy); INFN—Laboratori Nazionali di Legnaro, Viale dell’Università 2, 35020 Legnaro, Padova (Italy); Agostinetti, Piero; Marcuzzi, Diego; Sartori, Emanuele; Serianni, Gianluigi [Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Corso Stati Uniti 4, Padova (Italy)

    2016-06-15

    Neutral beam injectors are routinely used to increase the ion temperature in magnetically confined plasmas. Typically, the beam is produced by neutralizing a bundle of hundreds of ion beamlets, energized in a multi-grid multi-stage accelerator. Precise aiming of each beamlet is required in order to focus the full beam to the plasma, avoiding any interception with beamline surfaces and with the beam duct. This paper describes the effects of grid in-plane and out-of-plane displacements (mispositioning, thermal expansion, grid tilting, etc…) in the case of the MITICA electrostatic accelerator, which is the full scale prototype of the ITER heating neutral beam injector. Various simulations have been carried out with the OPERA 3D code, by self-consistently simulating the beam charged particles travelling in an externally applied electric and magnetic field. The accelerator grids act like a series of electrostatic lenses, and produce a net deflection of the particles when one or more grids are offset. The numerical simulations were used to evaluate the “steering constant” of each grid and also showed that the linear superposition of effects was applicable, multiple causes of mispositioning are combined and used to quantify the overall effect in terms of beam misalignment.

  1. The influence of grid positioning on the beam optics in the neutral beam injectors for ITER

    International Nuclear Information System (INIS)

    Veltri, Pierluigi; Agostinetti, Piero; Marcuzzi, Diego; Sartori, Emanuele; Serianni, Gianluigi

    2016-01-01

    Neutral beam injectors are routinely used to increase the ion temperature in magnetically confined plasmas. Typically, the beam is produced by neutralizing a bundle of hundreds of ion beamlets, energized in a multi-grid multi-stage accelerator. Precise aiming of each beamlet is required in order to focus the full beam to the plasma, avoiding any interception with beamline surfaces and with the beam duct. This paper describes the effects of grid in-plane and out-of-plane displacements (mispositioning, thermal expansion, grid tilting, etc…) in the case of the MITICA electrostatic accelerator, which is the full scale prototype of the ITER heating neutral beam injector. Various simulations have been carried out with the OPERA 3D code, by self-consistently simulating the beam charged particles travelling in an externally applied electric and magnetic field. The accelerator grids act like a series of electrostatic lenses, and produce a net deflection of the particles when one or more grids are offset. The numerical simulations were used to evaluate the “steering constant” of each grid and also showed that the linear superposition of effects was applicable, multiple causes of mispositioning are combined and used to quantify the overall effect in terms of beam misalignment

  2. Neutral beam source commercialization study. Final report

    International Nuclear Information System (INIS)

    King, H.J.

    1980-06-01

    The basic tasks of this Phase II project were to: generate a set of design drawings suitable for quantity production of sources of this design; fabricate a functional neutral beam source incorporating as many of the proposed design changes as proved feasible; and document the procedures and findings developed during the contract. These tasks have been accomplished and represent a demonstrated milestone in the industrialization of this complete device

  3. Ion beam assisted film growth

    CERN Document Server

    Itoh, T

    2012-01-01

    This volume provides up to date information on the experimental, theoretical and technological aspects of film growth assisted by ion beams.Ion beam assisted film growth is one of the most effective techniques in aiding the growth of high-quality thin solid films in a controlled way. Moreover, ion beams play a dominant role in the reduction of the growth temperature of thin films of high melting point materials. In this way, ion beams make a considerable and complex contribution to film growth. The volume will be essential reading for scientists, engineers and students working in thi

  4. Neutral beam interlock system on TFTR using infrared pyrometry

    International Nuclear Information System (INIS)

    Medley, S.S.; Kugel, H.W.; Kozub, T.A.; Lowrance, J.L.; Mastrocola, V.; Renda, G.; Young, K.M.

    1986-01-01

    Although the region of the Tokamak Fusion Test Reactor (TFTR) vacuum vessel wall which is susceptible to damage by neutral beam strike is armored with a mosaic of TiC-clad POCO graphite tiles, at power deposition levels above 2.5 kW/cm 2 the armor surface temperature exceeds 1200 0 C within 250 ms, and itself becomes susceptible to damage. In order to protect the wall armor, a neutral beam interlock system based on infrared pyrometry measurement of the armor surface temperature was installed on TFTR. For each beamline, a three-fiber-optic telescope views three areas of --30 cm diameter centered on the armor hot spots for the three ion sources. Each signal is fiber-optic coupled to a remote 900-nm pyrometer which feeds analog signals to the neutral beam interrupt circuits. The pyrometer interlock system is designed to interrupt each of the 12 ion sources independently within 10 ms of the temperature exceeding a threshold which can be set in the range of 500--2300 0 C. A description of the pyrometer interlock system and its performance will be presented

  5. Plasma-Immersion Formation of High-Intensity Ion Beams

    Science.gov (United States)

    Ryabchikov, A. I.; Anan'in, P. S.; Dektyarev, S. V.; Sivin, D. O.; Shevelev, A. E.

    2017-12-01

    For the first time, the possibility of forming high-intensity beams of low-energy metal and gas ions is demonstrated experimentally. The use of a hybrid system for ion-beam formation including plasmaimmersion extraction and ion acceleration and their subsequent ballistic focusing in an equipotential space with neutralization of the space charge of the beam made possible the pulse-periodic formation of titanium and nitrogen ion beams with an ion-current density of more than 1 A/cm2 and a pulsed power density of 2.6 kW/cm2.

  6. Ion beam generation and focusing

    International Nuclear Information System (INIS)

    Miller, P.A.; Mendel, C.W.; Swain, D.W.; Goldstein, S.A.

    1975-01-01

    Calculations have shown that efficiently generated and focused ion beams could have significant advantages over electron beams in achieving ignition of inertially-confined thermonuclear fuel. Efficient ion beam generation implies use of a good ion source and suppression of net electron current. Net electron flow can be reduced by allowing electrons to reflex through a highly transparent anode or by use of transverse magnetic fields (either beam self-fields or externally applied fields). Geometric focusing can be achieved if the beam is generated by appropriately shaped electrodes. Experimental results are presented which demonstrate ion beam generation in both reflexing and pinched-flow diodes. Spherically shaped electrodes are used to concentrate a proton beam, and target response to proton deposition is studied

  7. Simulation of Planned Neutral Beam Heating Experiments in SSPX

    Science.gov (United States)

    Foster, R. L.; Hill, D. N.; Pearlstein, L. D.; Casper, T. A.

    2006-10-01

    Recent results from the SSPX spheromak (peak Te 350eV) provide strong motivation for adding auxiliary heating to study energy transport and pressure limits. We are now procuring two 25keV 900kW neutral beam sources from Budker Institute in Russia. In parallel, we are using the CORSICA transport code to examine the effect of beam input geometry of the efficiency of neutral beam heating in a spheromak such as SSPX. A new fast-ion orbit-following algorithm was recently added to CORSICA to account for the low field, low aspect-ratio magnetic topology of the spheromak configuration [1]. We find a significant increase in fast ion confinement and subsequent plasma heating as the injection angle moves from strictly radial to more tangential injection. Variation of the heating rate with magnetic field, plasma density, and confinement time were also examined. The schedule for proposed beam installation and development of suitable target plasmas and diagnostics also will be presented. [1] L.D. Pearlstein, et al., Proceedings 33rd EPS Conf. on Plasma Physics, Rome (2006)

  8. Confinement studies during neutral beam injection in PLT

    International Nuclear Information System (INIS)

    Goldston, R.; Davis, S.; Eubank, H.

    1980-12-01

    Neutral beam injection experiments on PLT have provided definitive information on ion energy confinement in highly collisionless plasmas. We find that ion thermal conduction is consistent, within a factor of approx. 3, with neoclassical theory, and that anomalous thermal convection of ion energy is a factor of 2-3 less than would be calculated from the INTOR D/sub e/ with a convection loss term of the form 5/2nkTv/sub r/. From our experiments with a shunted TF coil we have found that a single shallow ripple well of 2.5% has a neglible effect on ion energy confinement, even at the lowest collisionality obtainable on PLT. Scrutiny of the analytic theories of ripple induced transport motivated by these experiments, suggests that more theoretical (and perhaps numerical) work is needed in this area

  9. Electron temperature effects for an ion beam source

    International Nuclear Information System (INIS)

    Uramoto, Joshin.

    1979-05-01

    A hydrogen high temperature plasma up to 200 eV is produced by acceleration of electrons in a hot hollow cathode discharge and is used as an ion beam source. Then, two characteristics are observed: A rate of the atomic ion (H + ) number increases above 70%. A perveance of the ion beam increases above 30 times compared with that of a cold plasma, while a floating potential of an ion acceleration electrode approaches an ion acceleration potential (- 500 V) according as an increment of the electron temperature. Moreover, a neutralized ion beam can be produced by only the negative floating electrode without an external power supply. (author)

  10. Analysis of particle species evolution in neutral-beam injection lines

    International Nuclear Information System (INIS)

    Kim, J.; Haselton, H.H.

    1979-01-01

    Analytic solutions to the rate equations describing the species evolution of a multispecies positive ion beam of hydrogen due to charge exchange and molecular dissociation are derived as a function of the background gas (H 2 ) line density in the neutralizing gas cell and in the drift tube. Using the solutions, calculations are presented for the relative abundance of each species as a function of the gas-cell thickness, the reionization loss in the drift tube, and the neutral-beam power as a function of the beam energy and the species composition of the original ion beam

  11. Spacecraft ion beam noise effects

    Science.gov (United States)

    Anenberg, G. L.

    1972-01-01

    An estimate of the antenna noise temperature and the uplink signal-to-noise ratio has been made for Bremsstrahlung radiation emitted by a spacecraft ion beam; a worst-case situation in which the spacecraft antenna is located in the exit plane of the ion beam and directed at varying angles into the ion beam is assumed. Numerical results of the antenna noise temperature versus antenna pointing angle are given for a typical set of ion beam and antenna pattern parameters. The uplink signal-to-noise ratio due to the ion beam noise alone is given in terms of a critical range in AU at which a typical ranging transmission is received with S/N = 0 db. The effects of the ion beam divergence angle and antenna distance on the ion beam are also presented. Results of the study show typical increases in the antenna noise temperature of about 0.2 K and critical ranges of the order of 3-5 AU. An ion engine thus generally introduces an undetectable level of noise into a spacecraft receiver.

  12. Targets for a Neutral Kaon Beam

    Energy Technology Data Exchange (ETDEWEB)

    Keith, Christopher [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2016-04-01

    A secondary beam of neutral Kaons is under consideration for Hall D at Jefferson Lab to perform spectroscopic studies of hyperons produced by K 0 L particles scattering from proton and deuteron targets. The proposed physics program would utilize the GlueX detector package currently installed in Hall D. This contribution looks at potential targets for use in the new facility, paying close attention to the existing infrastructure of GlueX and Hall D. Unpolarized cryotargets of liquid hydrogen and deuerium, as well as polarized solid targets of protons and deuterons are examined.

  13. Improvement of surface roughness in silicon-on-insulator wafer fabrication using a neutral beam etching

    Science.gov (United States)

    Min, T. H.; Park, B. J.; Kang, S. K.; Gweon, G. H.; Kim, Y. Y.; Yeom, G. Y.

    2009-08-01

    Silicon-on-insulator (SOI) wafers were etched by an energetic chlorine neutral beam obtained by the low-angle forward reflection of an ion beam, and the surface roughness of the etched wafers was compared with that of the SOI wafers etched by an energetic chlorine ion beam. When the ion beam was used to etch the silicon layer of the SOI wafers, the surface roughness was not significantly changed even though the use of higher ion bombardment energy slightly decreased the surface roughness of the SOI wafer. However, when the chlorine neutral beam was used instead of the chlorine ion beam having a similar beam energy, the surface roughness of the SOI wafer was significantly improved compared with that etched by the chlorine ion beam. By etching about 150 nm silicon from the SOI wafer having a 300 nm-thick top silicon layer with the chlorine neutral beam at the energy of 500 eV, the rms surface roughness of 1.5 Å could be obtained with the etch rate of about 750 Å min-1.

  14. Active spectroscopy upgrades and neutral beam injection on LTX- β

    Science.gov (United States)

    Elliott, Drew; Biewer, Theodore; Canik, John; Reinke, Matthew; Bell, Ronald; Boyle, Dennis; Guttenfelder, Walter; Kaita, Robert; Kozub, Thomas; Majeski, Richard; Merino, Enrique

    2017-10-01

    The LTX- β upgrade includes the addition of neutral beam injection (NBI) and increased active spectroscopy. Typical plasmas have been and are expected to remain inboard limited, at 14 cm with minor radii of 18-23 cm. The NBI, 35 Amps of 20 keV particles, will enable active diagnosis of ion velocity distribution profiles through charge exchange (CHERS). 18 CHERS views will cover more than a full minor radius, each sampling 2 cm of major radius. The system has both a set of beam directed ``active'' views and a symmetric set of views pointing away from the beam for stray light subtraction. Along with measuring ion temperatures and impurity transport, the CHERS diagnostic will measure the plasma rotation profiles. The recently described low recycling regime is predicted to allow for high rotational velocities due to the low neutral drag. The planned NBI has been predicted to give on axis velocities near 100 km/s. Flow shear is expected to increase confinement in this regime by suppressing trapped electron mode and other microturbulence enhanced transport. Upgrades to the Thomson scattering system, including an array of polychromators and a new camera, will assist in diagnosing the low density hot edge in this low recycling regime. Supported by US DOE contracts DE-AC02-09CH11466 and DE-AC05-00OR22725.

  15. Intense beams of light ions

    International Nuclear Information System (INIS)

    Camarcat, Noel

    1985-01-01

    Results of experiments performed in order to accelerate intense beams of light and heavier ions are presented. The accelerating diodes are driven by existing pulsed power generators. Optimization of the generator structure is described in chapter I. Nuclear diagnostics of the accelerated light ion beams are presented in chapter II. Chapter III deals with the physics of intense charged particle beams. The models developed are applied to the calculation of the performances of the ion diodes described in the previous chapters. Chapter IV reports preliminary results on a multiply ionized carbon source driven by a 0.1 TW pulsed power generator. (author) [fr

  16. Neutral injector using an ion source at the electron cyclotron resonance

    International Nuclear Information System (INIS)

    Jacquot, C.; Ludwig, P.; Sermet, P.

    1976-07-01

    The problems connected with the use of an ion source operating at the electron cyclotron resonance to obtain neutral particles from negative ions are studied. Ionization efficiency, beam divergence, ion beam transport in a uniform B field and electron capture of D + on a narrow alcali target to produce D - are examined. A new project of injector to create 0.3 A of negative ions is presented [fr

  17. Two-stage acceleration of an ion beam for high power ion source

    International Nuclear Information System (INIS)

    Ohara, Yoshihiro

    1979-07-01

    In research and development of a high power ion source for the JT-60 neutral beam injector, beam optics in the two-stage acceleration system has been investigated both numerically and experimentally. A computer code for cylindrically symmetric ion beam was developed for the simulation. By making use of this code, behaviour of the two-stage ion beam optics was clarified. The calculation results agreed well with the experimental ones. Experimentally, the gradient grid current and the grid heat loading proved to depend largely on the beam optics. The beam focusing by aperture displacement was investigated in thin lens approximation. The results obtained contributed to design and development of a high power ion source for the JT-60 neutral beam injector. (author)

  18. Development of data acquisition and over-current protection systems for a suppressor-grid current with a neutral-beam ion source

    Science.gov (United States)

    Wei, LIU; Chundong, HU; Sheng, LIU; Shihua, SONG; Jinxin, WANG; Yan, WANG; Yuanzhe, ZHAO; Lizhen, LIANG

    2017-12-01

    Neutral beam injection is one of the effective auxiliary heating methods in magnetic-confinement-fusion experiments. In order to acquire the suppressor-grid current signal and avoid the grid being damaged by overheating, a data acquisition and over-current protection system based on the PXI (PCI eXtensions for Instrumentation) platform has been developed. The system consists of a current sensor, data acquisition module and over-current protection module. In the data acquisition module, the acquired data of one shot will be transferred in isolation and saved in a data-storage server in a txt file. It can also be recalled using NBWave for future analysis. The over-current protection module contains two modes: remote and local. This gives it the function of setting a threshold voltage remotely and locally, and the forbidden time of over-current protection also can be set by a host PC in remote mode. Experimental results demonstrate that the data acquisition and over-current protection system has the advantages of setting forbidden time and isolation transmission.

  19. Manufacturing of neutral beam sources at Lawrence Livermore Laboratory

    International Nuclear Information System (INIS)

    Baird, E.D.; Duffy, T.J.; Harter, G.A.; Holland, E.D.; Kloos, W.A.; Pastrone, J.A.

    1979-01-01

    Over 50 neutral beam sources (NBS) of the joint Lawrence Berkeley Laboratory (LBL)/Lawrence Livermore Laboratory (LLL) design have been manufactured, since 1973, in the LLL Neutral Beam Source Facility. These sources have been used to provide start-up and sustaining neutral beams for LLL mirror fusion experiments, including 2XIIB, TMX, and Beta II. Experimental prototype 20-kV and 80-kV NBS have also been designed, built, and tested for the Mirror Fusion Test Facility (MFTF)

  20. Gas flow and related beam losses in the ITER neutral beam injector

    International Nuclear Information System (INIS)

    Krylov, A.; Hemsworth, R.S.

    2006-01-01

    The gas flow in the ITER neutral beam injectors has been studied using a 3D Monte-Carlo code to define a number of key parameters affecting the design and operation of the injector. This paper presents the results of calculations of the gas density in the two accelerator concepts presently considered as options for the ITER injectors, and the resultant stripping losses of the negative ions during their acceleration to 1 MeV. The sensitivity of the model to various parameters has been studied, including the gas temperature in the ion source and the subsequent accommodation by collisions with the accelerator structure, and the degree of dissociation of the D 2 or H 2 in the ion source, and subsequent recombination during collisions with the accelerator structure. Additionally the sensitivity of the losses to details of the beam source design and operating parameters are examined for the both accelerator concepts. (author)

  1. Propagation of light ion beam

    International Nuclear Information System (INIS)

    Okada, Toshio; Murakami, Hiroyuki; Niu, Keishiro.

    1983-01-01

    A method of rotating ion layer is proposed as a possible driver for inertial confinement fusion for the purpose of obtaining more stable ion beam against various micro- and macroinstabilities. The analysis was carried out within the frameworks of Vlasov and fluid models. A rotating ion layer propagating in the Z-direction is considered. The beam is described by a distribution function which satisfies the Vlasov equation. The equilibrium and microstability were studied. The filamentation instability is suppressed by a magnetic field due to the rotation of ion beam. To study the properties of the equilibrium state from the macroscopic standpoint, the equation of continuity of ion beam, the equation of motion and the Maxwell equations are considered. It is shown that the macroinstability is stabilized by the magnetic field in the Z-direction. It was found that the most dangerous instability for the problem of the propagation of ion beam was able to be atabilized by using a rotating ion layer. (Kato, T.)

  2. Neutralisation and transport of negative ion beams: physics and diagnostics

    Science.gov (United States)

    Serianni, G.; Agostinetti, P.; Agostini, M.; Antoni, V.; Aprile, D.; Baltador, C.; Barbisan, M.; Brombin, M.; Cavenago, M.; Chitarin, G.; Dalla Palma, M.; Delogu, R.; Fellin, F.; Fonnesu, N.; Marconato, N.; Pasqualotto, R.; Pimazzoni, A.; Sartori, E.; Spagnolo, S.; Spolaore, M.; Veltri, P.; Zaniol, B.; Zaupa, M.

    2017-04-01

    Neutral beam injection is one of the most important methods of plasma heating in thermonuclear fusion experiments, allowing the attainment of fusion conditions as well as driving the plasma current. Neutral beams are generally produced by electrostatically accelerating ions, which are neutralised before injection into the magnetised plasma. At the particle energy required for the most advanced thermonuclear devices and particularly for ITER, neutralisation of positive ions is very inefficient so that negative ions are used. The present paper is devoted to the description of the phenomena occurring when a high-power multi-ampere negative ion beam travels from the beam source towards the plasma. Simulation of the trajectory of the beam and of its features requires various numerical codes, which must take into account all relevant phenomena. The leitmotiv is represented by the interaction of the beam with the background gas. The main outcome is the partial neutralisation of the beam particles, but ionisation of the background gas also occurs, with several physical and technological consequences. Diagnostic methods capable of investigating the beam properties and of assessing the relevance of the various phenomena will be discussed. Examples will be given regarding the measurements collected in the small flexible NIO1 source and regarding the expected results of the prototype of the neutral beam injectors for ITER. The tight connection between measurements and simulations in view of the operation of the beam is highlighted.

  3. Design of neutral beam injection power supplies for ITER

    International Nuclear Information System (INIS)

    Watanabe, Kazuhiro; Okumura, Yoshikazu; Ono, Youichi; Tanaka, Masanobu

    2000-03-01

    Design study on a power supply system for the ITER neutral beam injector(NBI) has been performed. Circuits of converter/inverter system and other components of the acceleration power supply whose capacity is 1 MV, 45 A have been designed in detail. Performance of the negative ion production power supplies such as an arc and an extraction power supplies was investigated using the EMTDC code. It was confirmed that ripples of 0.34%p-p for the extraction power supply and 1.7%p-p for the arc power supply are small enough. It was also confirmed that an energy input to a negative ion generator from the arc power supply at an arcing can be suppressed smaller than 8 J. The extraction power supply was designed to suppress the energy input lower than 13 J at the breakdown in the extractor. These performances satisfy the required specification of the power supply system. (author)

  4. Prospects for ion beam fusion

    Energy Technology Data Exchange (ETDEWEB)

    Martin, R.L.

    1977-01-01

    The promise of pellet fusion by high energy heavy ions has evolved very rapidly, partly because of prior pellet work in the laser and e beam programs and partly because of an inherently good match to the application. ERDA sponsored a summer study in 1976 which has had a significant impact on the direction the ion beam fusion program has evolved. Experimental R and D work has been initiated in three of the U.S. accelerator laboratories. Argonne's development program is described. This development work, if successful, should lead to a great deal of confidence that the concept of pellet fusion by high energy heavy ions is indeed practical.

  5. RAMI Analyses of Heating Neutral Beam and Diagnostic Neutral Beam Systems for ITER

    Science.gov (United States)

    Chang, D. H.; Lee, S.; Hemsworth, R.; van Houtte, D.; Okayama, K.; Sagot, F.; Schunke, B.; Svensson, L.

    2011-09-01

    A RAMI (Reliability, Availability, Maintainability, Inspectability) analysis has been performed for the heating (& current drive) neutral beam (HNB) and diagnostic neutral beam (DNB) systems of the ITER device [1-3]. The objective of these analyses is to implement RAMI engineering requirements for design and testing to prepare a reliability-centred plan for commissioning, operation, and maintenance of the system in the framework of technical risk control to support the overall ITER Project. These RAMI requirements will correspond to the RAMI targets for the ITER project and the compensating provisions to reach them as deduced from the necessary actions to decrease the risk level of the function failure modes. The RAMI analyses results have to match with the procurement plan of the systems.

  6. RAMI Analyses of Heating Neutral Beam and Diagnostic Neutral Beam Systems for ITER

    International Nuclear Information System (INIS)

    Chang, D. H.; Lee, S.; Hemsworth, R.; Houtte, D. van; Okayama, K.; Sagot, F.; Schunke, B.; Svensson, L.

    2011-01-01

    A RAMI (Reliability, Availability, Maintainability, Inspectability) analysis has been performed for the heating (and current drive) neutral beam (HNB) and diagnostic neutral beam (DNB) systems of the ITER device. The objective of these analyses is to implement RAMI engineering requirements for design and testing to prepare a reliability-centred plan for commissioning, operation, and maintenance of the system in the framework of technical risk control to support the overall ITER Project. These RAMI requirements will correspond to the RAMI targets for the ITER project and the compensating provisions to reach them as deduced from the necessary actions to decrease the risk level of the function failure modes. The RAMI analyses results have to match with the procurement plan of the systems.

  7. Ion beams in materials processing and analysis

    CERN Document Server

    Schmidt, Bernd

    2012-01-01

    This book covers ion beam application in modern materials research, offering the basics of ion beam physics and technology and a detailed account of the physics of ion-solid interactions for ion implantation, ion beam synthesis, sputtering and nano-patterning.

  8. Funneling of heavy ion beams

    International Nuclear Information System (INIS)

    Bongardt, K.; Karlsruhe Univ.; Sanitz, D.

    1982-01-01

    The funneling of heavy ion beams can be achieved by first bending the beams by septum magnets towards the common axis, and then deflecting them onto the axis by rf-deflector elements with time varying electric field strength. The main properties of these deflection elements are discussed, especially the increase of the transverse emittance. As an example beam envelopes are shown for funneling two 100 mA, 1.7 MEV/N Bisup(+2) beams into one 108 MHz Alvarez accelerator. (orig.)

  9. Two dimensional simulation of ion beam-plasm interaction | Echi ...

    African Journals Online (AJOL)

    Hybrid plasma simulation is a model in which different components of the plasma are treated differently. In this work the ions are treated as particles while the electrons are treated as a neutralizing background fluid through which electric signals may propagate. Deuterium ion beams incident on the tritium plasma interact ...

  10. Neutral-beam species determination from nuclear reaction products

    Science.gov (United States)

    Ruby, Lawrence; Stearns, J. Warren; Pyle, Robert V.

    1986-08-01

    Recent measurements designed to measure neutral-beam species by nuclear reaction analysis are reported. The detection system and several experiments intended to improve resolution and reduce noise are described. Results obtained at the LBL neutral-beam engineering test facility are discussed and compared with the predictions of optical Doppler-shift spectroscopy.

  11. Tokamak Fusion Test Reactor neutral beam injection system vacuum chamber

    International Nuclear Information System (INIS)

    Pedrotti, L.R.

    1977-01-01

    Most of the components of the Neutral Beam Lines of the Tokamak Fusion Test Reactor (TFTR) will be enclosed in a 50 cubic meter box-shaped vacuum chamber. The chamber will have a number of unorthodox features to accomodate both neutral beam and TFTR requirements. The design constraints, and the resulting chamber design, are presented

  12. Measurements of beam-ion confinement during tangential beam-driven instabilities in PBX [Princeton Beta Experiment

    International Nuclear Information System (INIS)

    Heidbrink, W.W.; Kaita, R.; Takahashi, H.; Gammel, G.; Hammett, G.W.; Kaye, S.

    1987-01-01

    During tangential injection of neutral beams into low density tokamak plasmas with β > 1% in the Princeton Beta Experiment (PBX), instabilities are observed that degrade the confinement of beam ions. Neutron, charge-exchange, and diamagnetic loop measurements are examined in order to identify the mechanism or mechanisms responsible for the beam-ion transport. The data suggest a resonant interaction between the instabilities and the parallel energetic beam ions. Evidence for some nonresonant transport also exists

  13. Modified source of a fast neutral atom beam with a controlled energy

    International Nuclear Information System (INIS)

    Gostev, V.A.; Elakhovskij, D.V.; Khakhaev, A.D.

    1980-01-01

    A source of a metastable helium atom beam with a controlled energy based on a phenomenon of resonant ion neutralization on the surface of a solid body is described. The neutral particle energy control is carried out by changing ion velocities before their transformation into metastable atoms. The results of experiments with a modified construction of atomic beam source are stated. These experiments were conducted to find the possibilities to control velocities of atoms in a flow as well as to elucidate the peculiarities of operation of a collimator-converter of this construction. Dependences of a halfwidth of the ion velocity distribution function on the ion source parameters have been investigated. The possibility for particle energy control in a collimated flow of fast neutral. atoms has been experimentally shown, it is also shown that a mean value of atom energy in a beam coincides with a value of mean energy of ions from which atoms are produced by the resonant neutralization method; the construction of the source provides the possibility to realize the method of ''overtaking beams'' for neutral atoms and as a result of this to give a possibility for studying atom-atom collisions in a wide energy range at relatively high densities of flows

  14. Performance study of the TFTR diagnostic neutral beam for active charge exchange measurements

    International Nuclear Information System (INIS)

    Medley, S.S.; Goldston, R.J.; Towner, H.H.

    1980-06-01

    A neutral beam source will be incorporated in the Tokamak Fusion Test Reactor (TFTR) charge exchange diagnostic to provide a time modulated, spatially localized enhancement of the charge exchange efflux. Two autonomous Charge Exchange Neutral Analyzer (CENA) systems are being designed for the TFTR. One system measures the plasma ion temperature along twelve vertical line-of-sight chords spaced approximately equidistantly across the torus minor diameter. The other system is dedicated primarily to measurement of ion phenomena associated with neutral beam injection heating and has a fan-like field of view along eight sight-lines in the equitorial plane. The neutral beam is steerable in order to access the viewing field of both CENA systems, though in general not simultaneously. The performance of the diagnostic neutral beam is evaluated to determine the optimal beam specifications for active charge exchange measurements. Using the optimal beam design parameters, the efficacy of the neutral doping is examined for both CENA systems over the envisioned range of the TFTR plasma density and temperature

  15. Novel neutralized-beam intense neutron source for fusion technology development

    International Nuclear Information System (INIS)

    Osher, J.E.; Perkins, L.J.

    1983-01-01

    We describe a neutralized-beam intense neutron source (NBINS) as a relevant application of fusion technology for the type of high-current ion sources and neutral beamlines now being developed for heating and fueling of magnetic-fusion-energy confinement systems. This near-term application would support parallel development of highly reliable steady-state higher-voltage neutral D 0 and T 0 beams and provide a relatively inexpensive source of fusion neutrons for materials testing at up to reactor-like wall conditions. Beam-target examples described incude a 50-A mixed D-T total (ions plus neutrals) space-charge-neutralized beam at 120 keV incident on a liquid Li drive-in target, or a 50-A T 0 + T + space-charge-neutralized beam incident on either a LiD or gas D 2 target with calculated 14-MeV neutron yields of 2 x 10 15 /s, 7 x 10 15 /s, or 1.6 x 10 16 /s, respectively. The severe local heat loading on the target surface is expected to limit the allowed beam focus and minimum target size to greater than or equal to 25 cm 2

  16. Neutral atom beam technique enhances bioactivity of PEEK

    International Nuclear Information System (INIS)

    Khoury, Joseph; Kirkpatrick, Sean R.; Maxwell, Melissa; Cherian, Raymond E.; Kirkpatrick, Allen; Svrluga, Richard C.

    2013-01-01

    Polyetheretherketone (PEEK) is currently gaining popularity in orthopedic and spinal applications but has potential drawbacks in use. PEEK is biocompatible, similar in elasticity to bone, and radiolucent; however, it has been shown to be inert and does not integrate well with bone. Recent efforts have focused on increasing the bioactivity of PEEK by modifying the surface to improve the bone-implant interface. We have employed a novel Accelerated Neutral Atom Beam technique (ANAB) to enhance the bioactivity of PEEK. ANAB employs an intense beam of cluster-like packets of accelerated unbonded neutral argon (Ar) gas atoms. These beams are created by first producing a highly energetic Gas Cluster Ion Beam (GCIB) comprised of van der Waals bonded Ar atoms, then transferring energy to the clusters so as to cause release of most of the interatomic bonds, and finally deflecting away the remaining electrically charged cluster cores of still bonded atoms. We identified that ANAB treatment of PEEK results in nanometer scale surface modifications as well as increased surface hydrophilicity. Human osteoblasts seeded onto the surface of ANAB-treated PEEK exhibited enhanced growth as compared to control PEEK as evidenced by cell proliferation assays and microscopy. This increase in bioactivity resulted in cell proliferation levels comparable to native titanium. An in vivo study using a rat calvarial critical size defect model revealed enhanced osseointegration where bone tissue formation was evident only on the ANAB treated PEEK. Taken together, these data suggest that ANAB treatment of PEEK has the potential to enhance its bioactivity, resulting in bone formation and significantly decreasing osseointegration time of orthopedic and spinal implants

  17. Status of the realization of the neutral beam test facility

    International Nuclear Information System (INIS)

    Toigo, Vanni

    2015-01-01

    The ITER Neutral Beam Injectors (NBI) are required to deliver 16.5 MW of additional heating power to the plasma, accelerating negative ions up to -1 MV with a beam current of 40A lasting up to 1 hour. Since these outstanding requirements were never achieved all together so far, the realization of a Neutral Beam Test Facility (NBTF), called PRIMA, currently under construction in Padova, was launched with the aim to test the operation of the NB injector and to study the relevant physical and technological issues, in advance to the implementation in ITER. Two projects are under development: MITICA and SPIDER. MITICA is a full scale prototype of the ITER NB injector; the design is based on a similar scheme and layout, with the same power supply system and also the control and protection systems are being designed according to the ITER rules and constraints. The HV components are procured by JADA; the low voltage ones and the injector are procured by F4E. SPIDER project is an ion source with the same characteristics of the ITER one, specifically addressed to study the issues related to the RF operation; for this reason, the beam energy is limited to 100keV. It can generate both Hydrogen and Deuterium Ions; the design includes provisions to filter electrons and also to allow the use of cesium to attain the high values of current density required. SPIDER is procured by F4E and INDA. The construction of PRIMA buildings and auxiliaries, started in autumn 2008, was completed in summer 2015. SPIDER plant systems procurement is well advanced and some systems are under installation or site acceptance tests. In 2016 integrated commissioning and power supply integrated tests will be performed followed by the beginning of the first experimental phase. MITICA design was completed; many procurement contracts have been signed or will be launched in the next months. Installation activity will start in December 2015 with the installation of the first HV power supply components provided

  18. Maskless, resistless ion beam lithography

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Qing [Univ. of California, Berkeley, CA (United States)

    2003-01-01

    As the dimensions of semiconductor devices are scaled down, in order to achieve higher levels of integration, optical lithography will no longer be sufficient for the needs of the semiconductor industry. Alternative next-generation lithography (NGL) approaches, such as extreme ultra-violet (EUV), X-ray, electron-beam, and ion projection lithography face some challenging issues with complicated mask technology and low throughput. Among the four major alternative NGL approaches, ion beam lithography is the only one that can provide both maskless and resistless patterning. As such, it can potentially make nano-fabrication much simpler. This thesis investigates a focused ion beam system for maskless, resistless patterning that can be made practical for high-volume production. In order to achieve maskless, resistless patterning, the ion source must be able to produce a variety of ion species. The compact FIB system being developed uses a multicusp plasma ion source, which can generate ion beams of various elements, such as O2+, BF2+, P+ etc., for surface modification and doping applications. With optimized source condition, around 85% of BF2+, over 90% of O2+ and P+ have been achieved. The brightness of the multicusp-plasma ion source is a key issue for its application to maskless ion beam lithography. It can be substantially improved by optimizing the source configuration and extractor geometry. Measured brightness of 2 keV He+ beam is as high as 440 A/cm2 • Sr, which represents a 30x improvement over prior work. Direct patterning of Si thin film using a focused O2+ ion beam has been investigated. A thin surface oxide film can be selectively formed using 3 keV O2+ ions with the dose of 1015 cm-2. The oxide can then serve as a hard mask for patterning of the Si film. The

  19. Maskless, resistless ion beam lithography

    International Nuclear Information System (INIS)

    Ji, Qing

    2003-01-01

    As the dimensions of semiconductor devices are scaled down, in order to achieve higher levels of integration, optical lithography will no longer be sufficient for the needs of the semiconductor industry. Alternative next-generation lithography (NGL) approaches, such as extreme ultra-violet (EUV), X-ray, electron-beam, and ion projection lithography face some challenging issues with complicated mask technology and low throughput. Among the four major alternative NGL approaches, ion beam lithography is the only one that can provide both maskless and resistless patterning. As such, it can potentially make nano-fabrication much simpler. This thesis investigates a focused ion beam system for maskless, resistless patterning that can be made practical for high-volume production. In order to achieve maskless, resistless patterning, the ion source must be able to produce a variety of ion species. The compact FIB system being developed uses a multicusp plasma ion source, which can generate ion beams of various elements, such as O 2 + , BF 2 + , P + etc., for surface modification and doping applications. With optimized source condition, around 85% of BF 2 + , over 90% of O 2 + and P + have been achieved. The brightness of the multicusp-plasma ion source is a key issue for its application to maskless ion beam lithography. It can be substantially improved by optimizing the source configuration and extractor geometry. Measured brightness of 2 keV He + beam is as high as 440 A/cm 2 · Sr, which represents a 30x improvement over prior work. Direct patterning of Si thin film using a focused O 2 + ion beam has been investigated. A thin surface oxide film can be selectively formed using 3 keV O 2 + ions with the dose of 10 15 cm -2 . The oxide can then serve as a hard mask for patterning of the Si film. The process flow and the experimental results for directly patterned poly-Si features are presented. The formation of shallow pn-junctions in bulk silicon wafers by scanning focused P

  20. Ion beam analysis fundamentals and applications

    CERN Document Server

    Nastasi, Michael; Wang, Yongqiang

    2015-01-01

    Ion Beam Analysis: Fundamentals and Applications explains the basic characteristics of ion beams as applied to the analysis of materials, as well as ion beam analysis (IBA) of art/archaeological objects. It focuses on the fundamentals and applications of ion beam methods of materials characterization.The book explains how ions interact with solids and describes what information can be gained. It starts by covering the fundamentals of ion beam analysis, including kinematics, ion stopping, Rutherford backscattering, channeling, elastic recoil detection, particle induced x-ray emission, and nucle

  1. High harmonic ion cyclotron heating in DIII-D: Beam ion absorption and sawtooth stabilization

    International Nuclear Information System (INIS)

    Heidbrink, W.W.; Fredrickson, E.D.; Mau, T.K.; Petty, C.C.; Pinsker, R.I.; Porkolab, M.; Rice, B.W.

    1999-01-01

    Combined neutral beam injection and fast wave heating at the fourth cyclotron harmonic produce an energetic deuterium beam ion tail in the DIII-D tokamak. When the concentration of thermal hydrogen exceeds ∼ 5%, the beam ion absorption is suppressed in favour of second harmonic hydrogen absorption. As theoretically expected, the beam absorption increases with beam ion gyro-radius; also, central absorption at the fifth harmonic is weaker than central absorption at the fourth harmonic. For central heating at the fourth harmonic, an energetic, perpendicular, beam population forms inside the q = 1 surface. The beam ion tail transiently stabilizes the sawtooth instability but destabilizes toroidicity induced Alfven eigenmodes (TAEs). Saturation of the central heating correlates with the onset of the TAEs. Continued expansion of the q = 1 radius eventually precipitates a sawtooth crash; complete magnetic reconnection is observed. (author)

  2. Ion Beam Therapy in Europe

    International Nuclear Information System (INIS)

    Kraft, Gerhard

    2009-01-01

    At present, seven facilities in Europe treat deep-seated tumors with particle beams, six with proton beams and one with carbon ions. Three of these facilities are in Moscow, St. Petersburg and Dubna, Russia. Other facilities include the TSL Uppsala, Sweden, CPO Orsay, France, and PSI Villigen, Switzerland, all for proton therapy, and GSI, Darmstadt, Germany, which utilizes carbon ions only. But only two of these facilities irradiate with scanned ion beams: the Paul Scherer Institute (PSI), Villigen (protons) and the Gesellschaft fuer Schwerionenforschung (GSI), Darmstadt. These two facilities are experimental units within physics laboratories and have developed the technique of intensity-modulated beam scanning in order to produce irradiation conforming to a 3-D target. There are three proton centers presently under construction in Munich, Essen and Orsay, and the proton facility at PSI has added a superconducting accelerator connected to an isocentric gantry in order to become independent of the accelerator shared with the physics research program. The excellent clinical results using carbon ions at National Institute of Radiological Science (NIRS) in Chiba and GSI have triggered the construction of four new heavy-ion therapy projects (carbon ions and protons), located in Heidelberg, Pavia, Marburg and Kiel. The projects in Heidelberg and Pavia will begin patient treatment in 2009, and the Marburg and Kiel projects will begin in 2010 and 2011, respectively. These centers use different accelerator designs but have the same kind of treatment planning system and use the same approach for the calculation of the biological effectiveness of the carbon ions as developed at GSI [1]. There are many other planned projects in the works. Do not replace the word ''abstract,'' but do replace the rest of this text. If you must insert a hard line break, please use Shift+Enter rather than just tapping your ''Enter'' key. You may want to print this page and refer to it as a style

  3. Radiation Safety System for SPIDER Neutral Beam Accelerator

    Science.gov (United States)

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

    2011-12-01

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

  4. High current DC ion beams

    International Nuclear Information System (INIS)

    Shubaly, M.R.; de Jong, M.S.

    1983-01-01

    Development of high-current cw accelerators such as ZEBRA and FMIT, use of high current dc ion beams in industry for sputtering and material treatment, and scientific applications such as heavy-ion fusion and plasma physics diagnostics have provided the impetus for ion source development programs at many laboratories. At Chalk River, development of efficient plasma generators and reliable extraction columns to provide high quality beams of hydrogen, nitrogen, argon and xenon is underway. DC beams of up to 850 mA (limited by available power supplies) of hydrogen, 200 mA of nitrogen, 155 mA of argon and 100 mA of xenon have been produced with good reliability. DuoPIGatrons, with and without magnetic cusps, are used to generate a high density, reasonably quiescent plasma. Multi-aperture accel-decel columns are used for extraction with shaped apertures and beamlet steering to improve beam quality. This paper describes the performance of these sources and identifies some of the remaining problems. Guidelines for extraction column design, and experience with transporting high current beams are also presented

  5. Energy composition of high-energy neutral beams on the COMPASS tokamak

    Directory of Open Access Journals (Sweden)

    Mitosinkova Klara

    2016-12-01

    Full Text Available The COMPASS tokamak is equipped with two identical neutral beam injectors (NBI for additional plasma heating. They provide a beam of deuterium atoms with a power of up to ~(2 × 300 kW. We show that the neutral beam is not monoenergetic but contains several energy components. An accurate knowledge of the neutral beam power in each individual energy component is essential for a detailed description of the beam- -plasma interaction and better understanding of the NBI heating processes in the COMPASS tokamak. This paper describes the determination of individual energy components in the neutral beam from intensities of the Doppler-shifted Dα lines, which are measured by a high-resolution spectrometer viewing the neutral beam-line at the exit of NBI. Furthermore, the divergence of beamlets escaping single aperture of the last accelerating grid is deduced from the width of the Doppler-shifted lines. Recently, one of the NBI systems was modified by the removal of the Faraday copper shield from the ion source. The comparison of the beam composition and the beamlet divergence before and after this modification is also presented.

  6. Radioactive ion beams at TRIUMF

    International Nuclear Information System (INIS)

    D'Auria, J.M.; Dombsky, M.; Buchmann, L.; Sprenger, H.; McNeely, P.; Roy, G.

    1992-01-01

    The thick target, on-line isotope separator, TISOL, located at the high intensity, 500 MeV proton cyclotron, TRIUMF, has now been upgraded to a production facility, and can produce mass separated radioisotopic beams for a wide range of elements. Two different types of ion sources, an Electron Cyclotron Resonance (ECR) system and a heated surface ion source are presently operational for alkali, alkaline, and gaseous elements. A new class of target materials, zeolites, have been developed to allow the use of beam intensities approaching 5 μA. A summary of the experimental program underway is presented along with planned future upgrades, and recent results on the properties of nuclides far from stability. The role of TISOL in future planned accelerated radioactive beams facilities is also discussed

  7. Maintenance schemes for the ITER neutral beam test facility

    International Nuclear Information System (INIS)

    Zaccaria, P.; Dal Bello, S.; Marcuzzi, D.; Masiello, A.; Coniglio, A.; Antoni, V.; Cordier, J.J.; Hemsworth, R.; Jones, T.; Di Pietro, E.; Mondino, P.L.

    2004-01-01

    The ITER neutral beam test facility (NBTF) is planned to be built, after the approval of the ITER construction and the choice of the ITER site, with the agreement of the ITER International Team and of the JA and RF participant teams. The key purpose is to progressively increase the performance of the first ITER injector and to demonstrate its reliability at the maximum operation parameters: power delivered to the plasma 16.5 MW, beam energy 1 MeV, accelerated D - ion current 40 A, pulse length 3600 s. Several interventions for possible modifications and for maintenance are expected during the early operation of the ITER injector in order to optimize the beam generation, aiming and steering. The maintenance scheme and the related design solutions are therefore a very important aspect to be considered for the NBTF design. The paper describes consistently the many interrelated aspects of the design, such as the optimisation of the vessel and cryopump geometry, in order to get a better maintenance flexibility, an easier man access and a larger access for diagnostic and monitoring. (authors)

  8. Multi-slit triode ion optical system with ballistic beam focusing

    Energy Technology Data Exchange (ETDEWEB)

    Davydenko, V., E-mail: V.I.Davydenko@inp.nsk.su; Amirov, V.; Gorbovsky, A.; Deichuli, P.; Ivanov, A.; Kolmogorov, A.; Kapitonov, V.; Mishagin, V.; Shikhovtsev, I.; Sorokin, A.; Stupishin, N. [Budker Institute of Nuclear Physics, Novosibirsk 630090 (Russian Federation); Karpushov, A. N. [Ecole Polytechnique Fédérale de Lausanne, Centre de Recherches en Physique des Plasmas (CRPP), CH-1015 Lausanne (Switzerland); Smirnov, A. [Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688 (United States); Uhlemann, R. [Institute of Energy and Climate Research-Plasma Physics, Research Center Juelich, 52425 Juelich (Germany)

    2016-02-15

    Multi-slit triode ion-optical systems with spherical electrodes are of interest for formation of intense focused neutral beams for plasma heating. At present, two versions of focusing multi-slit triode ion optical system are developed. The first ion optical system forms the proton beam with 15 keV energy, 140 A current, and 30 ms duration. The second ion optical system is intended for heating neutral beam injector of Tokamak Configuration Variable (TCV). The injector produces focused deuterium neutral beam with 35 keV energy, 1 MW power, and 2 s duration. In the later case, the angular beam divergence of the neutral beam is 20-22 mrad in the direction across the slits of the ion optical system and 12 mrad in the direction along the slits.

  9. Nanostructuring by ion beam

    International Nuclear Information System (INIS)

    Valbusa, U.; Boragno, C.; Buatier de Mongeot, F.

    2003-01-01

    In metals, the surface curvature dependence of the sputtering yield and the presence of an extra energy barrier whenever diffusing adatoms try to descend step edges, produce a similar surface instability, which builds up regular patterns. By tuning the competition between these two mechanisms, it is possible to create self-organized structures of the size of few nanometers. Height, lateral distance and order of the structures change with the deposition parameters like ion energy, dose, incident angle and substrate temperature. The paper offers an overview of the experiments carried out and foresees possible applications of these results in the area of material science

  10. Materials Science with Ion Beams

    CERN Document Server

    Bernas, Harry

    2010-01-01

    This book introduces materials scientists and designers, physicists and chemists to the properties of materials that can be modified by ion irradiation or implantation. These techniques can help design new materials or to test modified properties; novel applications already show that ion-beam techniques are complementary to others, yielding previously unattainable properties. Also, ion-beam interactions modify materials at the nanoscale, avoiding the often detrimental results of lithographic or chemical techniques. Here, the effects are related to better-known quasi-equilibrium thermodynamics, and the consequences to materials are discussed with concepts that are familiar to materials science. Examples addressed concern semiconductor physics, crystal and nanocluster growth, optics, magnetism, and applications to geology and biology.

  11. DIAGNOSTICS FOR ION BEAM DRIVEN HIGH ENERGY DENSITY PHYSICS EXPERIMENTS

    International Nuclear Information System (INIS)

    Bieniosek, F.M.; Henestroza, E.; Lidia, S.; Ni, P.A.

    2010-01-01

    Intense beams of heavy ions are capable of heating volumetric samples of matter to high energy density. Experiments are performed on the resulting warm dense matter (WDM) at the NDCX-I ion beam accelerator. The 0.3 MeV, 30-mA K + beam from NDCX-I heats foil targets by combined longitudinal and transverse neutralized drift compression of the ion beam. Both the compressed and uncompressed parts of the NDCX-I beam heat targets. The exotic state of matter (WDM) in these experiments requires specialized diagnostic techniques. We have developed a target chamber and fielded target diagnostics including a fast multi-channel optical pyrometer, optical streak camera, laser Doppler-shift interferometer (VISAR), beam transmission diagnostics, and high-speed gated cameras. We also present plans and opportunities for diagnostic development and a new target chamber for NDCX-II.

  12. Diagnostics for ion beam driven high energy density physics experiments.

    Science.gov (United States)

    Bieniosek, F M; Henestroza, E; Lidia, S; Ni, P A

    2010-10-01

    Intense beams of heavy ions are capable of heating volumetric samples of matter to high energy density. Experiments are performed on the resulting warm dense matter (WDM) at the NDCX-I ion beam accelerator. The 0.3 MeV, 30 mA K(+) beam from NDCX-I heats foil targets by combined longitudinal and transverse neutralized drift compression of the ion beam. Both the compressed and uncompressed parts of the NDCX-I beam heat targets. The exotic state of matter (WDM) in these experiments requires specialized diagnostic techniques. We have developed a target chamber and fielded target diagnostics including a fast multichannel optical pyrometer, optical streak camera, laser Doppler-shift interferometer (Velocity Interferometer System for Any Reflector), beam transmission diagnostics, and high-speed gated cameras. We also present plans and opportunities for diagnostic development and a new target chamber for NDCX-II.

  13. Simulations of Beam Injection and Extraction into Ion Sources

    CERN Document Server

    Cavenago, Marco

    2005-01-01

    Charge breeding, consistiting of injecting singly charged ion into ECRIS(Electron Cyclotron Resonance Ion Sources) to extract an highly charged ion beam, is a promising technique for rare or radioactive ion beam. Efficiency and extracted beam temperature are dominated by the strong collisional diffusion of charged ion inside source. A computer code, named BEAM2ECR, written to simulate details of the injection, ionization, collision and extraction processes is described.* A model of injection plasma sheath and of source fringe field were recently added. Neutral injection is also supported, for comparison with other techniques, like gas feeding or metal vapor injection. Results, clearly favouring near axis injection for most cases are described. Code is written in C-language and possibility of concurrent execution over a Linux cluster was recently added.

  14. Low emittance growth in a low energy beam transport line with un-neutralized section

    Science.gov (United States)

    Prost, L.; Carneiro, J.-P.; Shemyakin, A.

    2018-02-01

    In a low energy beam transport line (LEBT), the emittance growth due to the beam's space charge is typically suppressed by way of neutralization from either electrons or ions, which originate from ionization of the background gas. In cases where the beam is chopped, the neutralization pattern usually changes throughout the beginning of the pulse, causing the Twiss parameters to differ significantly from their steady state values, which, in turn, may result in beam losses downstream. For a modest beam perveance, there is an alternative solution, in which the beam is kept un-neutralized in the portion of the LEBT that contains the chopper. The emittance can be nearly preserved if the transition to the un-neutralized section occurs where the beam exhibits low transverse tails. This report introduces the rationale for the proposed scheme and formulates the physical arguments for it as well as its limitations. An experimental realization of the scheme was carried out at Fermilab's PIP2IT where low beam emittance dilution was demonstrated for a 5 mA, 30 keV H- beam.

  15. Data acquisition system for medium power neutral beam test facility

    International Nuclear Information System (INIS)

    Stewart, C.R. Jr.; Francis, J.E. Jr.; Hammons, C.E.; Dagenhart, W.K.

    1978-06-01

    The Medium Power Neutral Beam Test Facility at Oak Ridge National Laboratory was constructed in order to develop, test, and condition powerful neutral beam lines for the Princeton Large Torus experiment at Princeton Plasma Physics Laboratory. The data acquisition system for the test stand monitors source performance, beam characteristics, and power deposition profiles to determine if the beam line is operating up to its design specifications. The speed of the computer system is utilized to provide near-real-time analysis of experimental data. Analysis of the data is presented as numerical tabulation and graphic display

  16. Data acquisition system for PLT Neutral Beam Test Stand

    International Nuclear Information System (INIS)

    Francis, J.E. Jr.; Hammons, C.E.

    1977-01-01

    The PLT Neutral Beam Test Stand at Oak Ridge National Laboratory was constructed to test and condition powerful neutral beam sources for the Princeton Large Torus experiment at Princeton Plasma Physics Laboratory. The data acquisition system for the test stand monitors the beam characteristics and power output to determine if the beam is operating at its design specifications. The high speed of the computer system is utilized to provide near-real-time analysis of experimental data. The analysis of the data is presented as numerical tabulation and graphic display

  17. Automation of neutral beam source conditioning with artificial intelligence techniques

    International Nuclear Information System (INIS)

    Johnson, R.R.; Canales, T.; Lager, D.

    1986-01-01

    This paper describes a system that automates neutral beam source conditioning. The system achieves this with artificial intelligence techniques. The architecture of the system is presented followed by a description of its performance

  18. Automation of neutral beam source conditioning with artificial intelligence techniques

    International Nuclear Information System (INIS)

    Johnson, R.R.; Canales, T.W.; Lager, D.L.

    1985-01-01

    This paper describes a system that automates neutral beam source conditioning. The system achieves this with artificial intelligence techniques. The architecture of the system is presented followed by a description of its performance

  19. Radioactive Ion Beams and Radiopharmaceuticals

    Science.gov (United States)

    Laxdal, R. E.; Morton, A. C.; Schaffer, P.

    2014-02-01

    Experiments performed at radioactive ion beam facilities shed new light on nuclear physics and nuclear structure, as well as nuclear astrophysics, materials science and medical science. The many existing facilities, as well as the new generation of facilities being built and those proposed for the future, are a testament to the high interest in this rapidly expanding field. The opportunities inherent in radioactive beam facilities have enabled the search for radioisotopes suitable for medical diagnosis or therapy. In this article, an overview of the production techniques and the current status of RIB facilities and proposals will be presented. In addition, accelerator-generated radiopharmaceuticals will be reviewed.

  20. Ion beam modification of polymers

    International Nuclear Information System (INIS)

    Sofield, C.J.; Sugden, S.; Ing, J.; Bridwell, L.B.; Wang, Y.Q.

    1993-01-01

    The implantation of polymers has received considerable attention in recent years, primarily to examine doping of conducting polymers and to increase the surface conductivity (by many orders of magnitude) of highly insulating polymers. The interest in these studies was partly motivated by possible applications to microelectronic device fabrication. More recently it has been observed that ion implantation can under some conditions lead to the formation of a hard (e.g. as hard as steel, ca. 3 MPa) and conducting surface layer. This paper will review the ion beam modification of polymers resulting from ion implantation with reference to fundamental ion-solid interactions. This leads us to examine whether or not implantation of polymers is a contradiction in terms. (Author)

  1. Neutral beam injection and plasma convection in a magnetic field

    International Nuclear Information System (INIS)

    Okuda, H.; Hiroe, S.

    1988-06-01

    Injection of a neutral beam into a plasma in a magnetic field has been studied by means of numerical plasma simulations. It is found that, in the absence of a rotational transform, the convection electric field arising from the polarization charges at the edges of the beam is dissipated by turbulent plasma convection, leading to anomalous plasma diffusion across the magnetic field. The convection electric field increases with the beam density and beam energy. In the presence of a rotational transform, polarization charges can be neutralized by the electron motion along the magnetic field. Even in the presence of a rotational transform, a steady-state convection electric field and, hence, anomalous plasma diffusion can develop when a neutral beam is constantly injected into a plasma. Theoretical investigations on the convection electric field are described for a plasma in the presence of rotational transform. 11 refs., 19 figs

  2. Magnetic analysis of the magnetic field reduction system of the ITER neutral beam injector

    Energy Technology Data Exchange (ETDEWEB)

    Barrera, Germán, E-mail: german.barrera@ciemat.es [CIEMAT, Laboratorio Nacional de Fusión, Avda. Complutense 22, 28040 Madrid (Spain); Ahedo, Begoña; Alonso, Javier; Ríos, Luis [CIEMAT, Laboratorio Nacional de Fusión, Avda. Complutense 22, 28040 Madrid (Spain); Chareyre, Julien; El-Ouazzani, Anass [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St Paul Lez Durance Cedex (France); Agarici, Gilbert [Fusion for Energy, Josep Pla 2, Torres Diagonal Litoral B3, 07/08, 08019 Barcelona (Spain)

    2015-10-15

    The neutral beam system for ITER consists of two heating and current drive neutral beam injectors (HNB) and a diagnostic neutral beam (DNB) injector. The proposed physical plant layout allows a possible third HNB injector to be installed later. For the correct operation of the beam, the ion source and the ion path until it is neutralized must operate under a very low magnetic field environment. To prevent the stray ITER field from penetrating inside those mentioned critical areas, a magnetic field reduction system (MFRS) will envelop the beam vessels and the high voltage transmission lines to ion source. This system comprises the passive magnetic shield (PMS), a box like assembly of thick low carbon steel plates, and the Active Correction and Compensation Coils (ACCC), a set of coils carrying a current which depends on the tokamak stray field. This paper describes the magnetic model and analysis results presented at the PMS and ACCC preliminary design review held in ITER organization in April 2013. The paper focuses on the magnetic model description and on the description of the analysis results. The iterative process for obtaining optimized currents in the coils is presented. The set of coils currents chosen among the many possible solutions, the magnetic field results in the interest regions and the fulfillment of the magnetic field requirements are described.

  3. Method of determining characteristics of a high-energy neutral beam and facility for performing the method

    International Nuclear Information System (INIS)

    Fink, J.H.

    1979-01-01

    The ion beam consisting of H, D, T and He serves to supply energy to a plasma. For monitoring the beam and certain characteristics it is passed through a neutralizing chamber containing a neutralizing gas, and the current, generated in circuits by ions drifting to the wall, is measured. For this purpose the chamber is subdivided into longitudinal or transversal segments being electrically insulated from each other. Each segment is part of a separate current-measuring device, the direction of propagation of the ion beam thus being also susceptible to measurement. (DG) [de

  4. Ion beam sputter implantation method

    International Nuclear Information System (INIS)

    King, W.J.

    1978-01-01

    By means of ion beam atomizing or sputtering an integrally composed coating, the composition of which continuously changes from 100% of the substrate to 100% of the coating, can be surfaced on a substrate (e.g. molten quartz on plastic lenses). In order to do this in the facility there is directed a primary beam of accelerated noble gas ions on a target from the group of the following materials: SiO 2 , Al 2 O 3 , Corning Glass 7070, Corning Glass 7740 or borosilicate glass. The particles leaving the target are directed on the substrate by means of an acceleration potential of up to 10 KV. There may, however, be coated also metal layers (Ni, Co) on a mylar film resulting in a semireflecting metal film. (RW) [de

  5. Materials research with ion beams

    International Nuclear Information System (INIS)

    Meyer, J.D.

    1988-01-01

    This report gives a series of helpful programs which are used in materials research with ion beams. In this context algorithms which can substitute table books are dealt with. This is true for the programs DEDX and PRAL; they are used in order to determine the energy loss of ions in solid bodies, their working range and straggling. Furthermore, simulator routines and analyzers are described. The program TRIM simulates the physical phenomena which occur with the penetration of high-energy ions into solid bodies. In this context electronic excitations, phonons and lattice distortions which are caused by the ions are dealt with. For the experimental ion implantation it is interesting to know the final distribution of the simulated ions in the solid body. The program RBS simulates the Rutherford spectrum of ions which are scattered from a solid body which may consist of up to nine elements and up to one hundred layers. The unknown composition of a solid body can be determined in direct comparison with the experimental spectrum. The program NRA determines concentration and penetrative distribution of an impurity by means of the experimental nuclear reaction spectrum of this impurity. All programs are written in FORTRAN 77. (orig./MM) [de

  6. Conceptual design of the beam source for the DEMO Neutral Beam Injectors

    Science.gov (United States)

    Sonato, P.; Agostinetti, P.; Fantz, U.; Franke, T.; Furno, I.; Simonin, A.; Tran, M. Q.

    2016-12-01

    DEMO (DEMOnstration Fusion Power Plant) is a proposed nuclear fusion power plant that is intended to follow the ITER experimental reactor. The main goal of DEMO will be to demonstrate the possibility to produce electric energy from the fusion reaction. The injection of high energy neutral beams is one of the main tools to heat the plasma up to fusion conditions. A conceptual design of the Neutral Beam Injector (NBI) for the DEMO fusion reactor, is currently being developed by Consorzio RFX in collaboration with other European research institutes. High efficiency and low recirculating power, which are fundamental requirements for the success of DEMO, have been taken into special consideration for the DEMO NBI. Moreover, particular attention has been paid to the issues related to reliability, availability, maintainability and inspectability. A conceptual design of the beam source for the DEMO NBI is here presented featuring 20 sub-sources (two adjacent columns of 10 sub-sources each), following a modular design concept, with each sub-source featuring its radio frequency driver, capable of increasing the reliability and availability of the DEMO NBI. Copper grids with increasing size of the apertures have been adopted in the accelerator, with three main layouts of the apertures (circular apertures, slotted apertures and frame-like apertures for each sub-source). This design, permitting to significantly decrease the stripping losses in the accelerator without spoiling the beam optics, has been investigated with a self-consistent model able to study at the same time the magnetic field, the electrostatic field and the trajectory of the negative ions. Moreover, the status on the R&D carried out in Europe on the ion sources is presented.

  7. Fault detection and protection system for neutral beam generators on the Neutral Beam Engineering Test Facility (NBETF)

    International Nuclear Information System (INIS)

    deVries, G.J.; Chesley, K.L.; Owren, H.M.

    1983-12-01

    Neutral beam sources, their power supplies and instrumentation can be damaged from high voltage sparkdown or from overheating due to excessive currents. The Neutral Beam Engineering Test Facility (NBETF) in Berkeley has protective electronic hardware that senses a condition outside a safe operating range and generates a response to terminate such a fault condition. A description of this system is presented in this paper. 8 references, 2 figures, 2 tables

  8. Design and characterization of a neutralized-transport experiment for heavy-ion fusion

    Directory of Open Access Journals (Sweden)

    Enrique Henestroza

    2004-08-01

    Full Text Available In heavy-ion inertial-confinement fusion systems, intense beams of ions must be transported from the exit of the final-focus magnet system through the fusion chamber to hit spots on the target with radii of about 2 mm. For the heavy-ion-fusion power-plant scenarios presently favored in the U.S., a substantial fraction of the ion-beam space charge must be neutralized during this final transport. The most effective neutralization technique found in numerical simulations is to pass each beam through a low-density plasma after the final focusing. To provide quantitative comparisons of these theoretical predictions with experiment, the Virtual National Laboratory for Heavy Ion Fusion has completed the construction and has begun experimentation with the neutralized-transport experiment. The experiment consists of three main sections, each with its own physics issues. The injector is designed to generate a very high-brightness, space-charge-dominated potassium beam, while still allowing variable perveance by a beam aperturing technique. The magnetic-focusing section, consisting of four pulsed quadrupoles, permits the study of magnet tuning, as well as the effects of phase-space dilution due to higher-order nonlinear fields. In the final section, the converging ion beam exiting the magnetic section is transported through a drift region with plasma sources for beam neutralization, and the final spot size is measured under various conditions of neutralization. In this paper, we discuss the design and characterization of the three sections in detail and present initial results from the experiment.

  9. A fast beam-ion instability

    Energy Technology Data Exchange (ETDEWEB)

    Stupakov, G.V. [Stanford Linear Accelerator Center, Menlo Park, CA (United States)

    1996-08-01

    The ionization of residual gas by an electron beam in an accelerator generates ions that can resonantly couple to the beam through a wave propagating in the beam-ion system. Results of the study of a beam-ion instability are presented for a multi-bunch train taking into account the decoherence of ion oscillations due to the ion frequency spread and spatial variation of the ion frequency. It is shown that the combination of both effects can substantially reduce the growth rate of the instability. (author)

  10. Design of the torus interface for the neutral beam injectors of Wendelstein 7-X

    Energy Technology Data Exchange (ETDEWEB)

    Nocentini, R., E-mail: riccardo.nocentini@ipp.mpg.de; Heinemann, B.; Riedl, R.; Rust, N.; Orozco, G.

    2015-11-15

    Highlights: • Two NBI injectors are installed in W7-X, each capable of hosting four ion sources. • The NBI boxes and their NBI ports in W7-X are connected by NBI–torus interfaces. • Each NBI–torus interface includes a DN800 bellow, copper scrapers and diagnostics. • The design of the NBI–torus interface has been challenging due to the shape of W7-X. • The design includes the numerical shape optimization of one of the beam scrapers. - Abstract: A neutral beam injection (NBI) heating system for the stellarator project Wendelstein 7-X (W7-X) is currently under construction at the Max Planck Institute for Plasma Physics (IPP) Greifswald, Germany. The NBI at W7-X is based on the similar system in operation on the tokamak ASDEX Upgrade at IPP in Garching, Germany, and makes use of radio-frequency-driven positive ion sources. Two NBI injectors are going to be installed in W7-X, each being capable of hosting four ion sources. Initially each injector is being equipped with two ion sources of 1.8 (2.5) MW beam power each in H (D). Accelerated positive ions are going to be neutralized and transported inside an NBI-box, which also hosts a residual ion dump, titanium sublimation pumps and a calorimeter. The beams are focused at a point 6.5 m downstream of the ion sources and are injected into the plasma vessel of W7-X through two ports. The NBI boxes and their NBI ports are connected by NBI–torus interfaces, which are made of several components that minimize beam losses while protecting the port walls and bellows from energetic re-ionized particles and beam intersection. This paper describes the design of the NBI–torus interface, including the shape optimization of a beam scraper and the integration of beam diagnostics.

  11. Sparking protection for MFTF-B neutral beam power supplies

    International Nuclear Information System (INIS)

    Cummings, D.B.

    1983-01-01

    This paper describes the upgrade of MFTF-B Neutral Beam Power Supplies for sparking protection. High performance ion sources spark repeatedly so ion source power supplies must be insensitive to sparking. The hot deck houses the series tetrode, arc and filament supplies, and controls. Hot deck shielding has been upgraded and a continuous shield around the arc, filament, gradient grid, and control cables now extends from the hot deck, through the core snubber, to the source. The shield carries accelerating current and connects only to the source. Shielded source cables go through an outer duct which now connects to a ground plane under the hot deck. This hybrid transmission line is a low inductance path for sparks discharging the stray capacitance of the hot deck and isolation transformers, reducing coupling to building steel. Parallel dc current return cables inside the duct lower inductance to reduce inductive turn-off transients. MOVs to ground further limit surges in the remote power supply return. Single point grounding is at the source. No control or rectifier components have been damaged nor are there any known malfunctions due to sparking up to 80 kV output

  12. Ion beam enhancement in magnetically insulated ion diodes for high-intensity pulsed ion beam generation in non-relativistic mode

    Science.gov (United States)

    Zhu, X. P.; Zhang, Z. C.; Pushkarev, A. I.; Lei, M. K.

    2016-01-01

    High-intensity pulsed ion beam (HIPIB) with ion current density above Child-Langmuir limit is achieved by extracting ion beam from anode plasma of ion diodes with suppressing electron flow under magnetic field insulation. It was theoretically estimated that with increasing the magnetic field, a maximal value of ion current density may reach nearly 3 times that of Child-Langmuir limit in a non-relativistic mode and close to 6 times in a highly relativistic mode. In this study, the behavior of ion beam enhancement by magnetic insulation is systematically investigated in three types of magnetically insulated ion diodes (MIDs) with passive anode, taking into account the anode plasma generation process on the anode surface. A maximal enhancement factor higher than 6 over the Child-Langmuir limit can be obtained in the non-relativistic mode with accelerating voltage of 200-300 kV. The MIDs differ in two anode plasma formation mechanisms, i.e., surface flashover of a dielectric coating on the anode and explosive emission of electrons from the anode, as well as in two insulation modes of external-magnetic field and self-magnetic field with either non-closed or closed drift of electrons in the anode-cathode (A-K) gap, respectively. Combined with ion current density measurement, energy density characterization is employed to resolve the spatial distribution of energy density before focusing for exploring the ion beam generation process. Consistent results are obtained on three types of MIDs concerning control of neutralizing electron flows for the space charge of ions where the high ion beam enhancement is determined by effective electron neutralization in the A-K gap, while the HIPIB composition of different ion species downstream from the diode may be considerably affected by the ion beam neutralization during propagation.

  13. Ion beam enhancement in magnetically insulated ion diodes for high-intensity pulsed ion beam generation in non-relativistic mode

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, X. P. [Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams, Ministry of Education, Dalian University of Technology, Dalian 116024 (China); Surface Engineering Laboratory, School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China); Zhang, Z. C.; Lei, M. K., E-mail: surfeng@dlut.edu.cn [Surface Engineering Laboratory, School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China); Pushkarev, A. I. [Surface Engineering Laboratory, School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China); Laboratory of Beam and Plasma Technology, High Technologies Physics Institute, Tomsk Polytechnic University, 30, Lenin Ave, 634050 Tomsk (Russian Federation)

    2016-01-15

    High-intensity pulsed ion beam (HIPIB) with ion current density above Child-Langmuir limit is achieved by extracting ion beam from anode plasma of ion diodes with suppressing electron flow under magnetic field insulation. It was theoretically estimated that with increasing the magnetic field, a maximal value of ion current density may reach nearly 3 times that of Child-Langmuir limit in a non-relativistic mode and close to 6 times in a highly relativistic mode. In this study, the behavior of ion beam enhancement by magnetic insulation is systematically investigated in three types of magnetically insulated ion diodes (MIDs) with passive anode, taking into account the anode plasma generation process on the anode surface. A maximal enhancement factor higher than 6 over the Child-Langmuir limit can be obtained in the non-relativistic mode with accelerating voltage of 200–300 kV. The MIDs differ in two anode plasma formation mechanisms, i.e., surface flashover of a dielectric coating on the anode and explosive emission of electrons from the anode, as well as in two insulation modes of external-magnetic field and self-magnetic field with either non-closed or closed drift of electrons in the anode-cathode (A-K) gap, respectively. Combined with ion current density measurement, energy density characterization is employed to resolve the spatial distribution of energy density before focusing for exploring the ion beam generation process. Consistent results are obtained on three types of MIDs concerning control of neutralizing electron flows for the space charge of ions where the high ion beam enhancement is determined by effective electron neutralization in the A-K gap, while the HIPIB composition of different ion species downstream from the diode may be considerably affected by the ion beam neutralization during propagation.

  14. Confinement studies of neutral beam heated discharges in TFTR

    International Nuclear Information System (INIS)

    Murakami, M.; Arunasalam, V.; Bell, J.D.; Stauffer, F.; Bell, M.G.; Bitte, M.; Blanchard, W.R.; Boody, F.; Britz, N.

    1985-11-01

    The TFTR tokamak has reached its original machine design specifications (I/sub p/ = 2.5 MA and B/sub T/ = 5.2T). Recently, the D 0 neutral beam heating power has been increased to 6.3 MW. By operating at low plasma current (I/sub p/ approx. = 0.8 MA) and low density anti n/sub e/ approx. = 1 x 10 19 m -3 ), high ion temperatures (9 +- keV) and rotation speeds (7 x 10 5 m/s) have been achieved during injection. At the opposite extreme, pellet injection into high current plasmas has been used to increase the line-average density to 8 x 10 19 m -3 and the central density to 1.6 x 10 20 m -3 / This wide range of operating conditions has enabled us to conduct scaling studies of the global energy confinement time in both ohmically and beam heated discharges as well as more detailed transport studies of the profile dependence. In ohmic discharges, the energy confinement time is observed to scale linearly with density only up to anti n/sub e/ approx. 4.5 x 10 19 m -3 and then to increase more gradually, achieving a maximum value of approx. 0.45 s. In beam heated discharges, the energy confinement time is observed to decrease with beam power and to increase with plasma current. With P/sub b/ = 5.6 MW, anti n/sub e/ = 4.7 x 10 19 m -3 , I/sub p/ = 2.2 MA and B/sub T = 4.7T, the gross energy confinement time is 0.22 s and T/sub i/(0) = 4.8 keV. Despite shallow penetration of D 0 beams (at the beam energy less than or equal to 80 keV with low species yield), tau/sub E/(a) values are as large as those for H 0 injection, but central confinement times are substantially greater. This is a consequence of the insensitivity of the temperature and safety factor profile shapes to the heating profile. The radial variation of tau/sub E/ is even more pronounced with D 0 injection into high density pellet-injected plasmas. 25 refs

  15. Confinement studies of neutral beam heated discharges in TFTR

    Energy Technology Data Exchange (ETDEWEB)

    Murakami, M.; Arunasalam, V.; Bell, J.D.; Stauffer, F.; Bell, M.G.; Bitte, M.; Blanchard, W.R.; Boody, F.; Britz, N.

    1985-11-01

    The TFTR tokamak has reached its original machine design specifications (I/sub p/ = 2.5 MA and B/sub T/ = 5.2T). Recently, the D/sup 0/ neutral beam heating power has been increased to 6.3 MW. By operating at low plasma current (I/sub p/ approx. = 0.8 MA) and low density anti n/sub e/ approx. = 1 x 10/sup 19/m/sup -3/), high ion temperatures (9 +- keV) and rotation speeds (7 x 10/sup 5/ m/s) have been achieved during injection. At the opposite extreme, pellet injection into high current plasmas has been used to increase the line-average density to 8 x 10/sup 19/m/sup -3/ and the central density to 1.6 x 10/sup 20/m/sup -3// This wide range of operating conditions has enabled us to conduct scaling studies of the global energy confinement time in both ohmically and beam heated discharges as well as more detailed transport studies of the profile dependence. In ohmic discharges, the energy confinement time is observed to scale linearly with density only up to anti n/sub e/ approx. 4.5 x 10/sup 19/m/sup -3/ and then to increase more gradually, achieving a maximum value of approx. 0.45 s. In beam heated discharges, the energy confinement time is observed to decrease with beam power and to increase with plasma current. With P/sub b/ = 5.6 MW, anti n/sub e/ = 4.7 x 10/sup 19/m/sup -3/, I/sub p/ = 2.2 MA and B/sub T = 4.7T, the gross energy confinement time is 0.22 s and T/sub i/(0) = 4.8 keV. Despite shallow penetration of D/sup 0/ beams (at the beam energy less than or equal to 80 keV with low species yield), tau/sub E/(a) values are as large as those for H/sup 0/ injection, but central confinement times are substantially greater. This is a consequence of the insensitivity of the temperature and safety factor profile shapes to the heating profile. The radial variation of tau/sub E/ is even more pronounced with D/sup 0/ injection into high density pellet-injected plasmas. 25 refs.

  16. Analysis of space-charge effects on the ion beam in a magnetic sector-type mass separator

    International Nuclear Information System (INIS)

    Nakai, A.

    1988-01-01

    Profiles of ion beams in a magnetic sector-type mass separator are analysed by comparing with calculated ion trajectories from viewpoint of the space-charge effect; the calculation is based on a new method which takes into account the space-charge effect analytically. In the analysis, the space-charge potential in the ion beam, an axial third order aberration at the ion beam source, the space-charge neutralization and a beam of neutral particles accompanied by the ion beam are discussed. Influences of the space-charge of the primary ions are also shown to be important in the analysis of the secondary electrons. (author)

  17. Neurosurgical applications of ion beams

    Science.gov (United States)

    Fabrikant, Jacob I.; Levy, Richard P.; Phillips, Mark H.; Frankel, Kenneth A.; Lyman, John T.

    1989-04-01

    The program at Donner Pavilion has applied nuclear medicine research to the diagnosis and radiosurgical treatment of life-threatening intracranial vascular disorders that affect more than half a million Americans. Stereotactic heavy-charged-particle Bragg peak radiosurgery, using narrow beams of heavy ions, demonstrates superior biological and physical characteristics in brain over X-and γ-rays, viz., improved dose distribution in the Bragg peak and sharp lateral and distal borders and less scattering of the beam. Examination of CNS tissue response and alteration of cerebral blood-flow dynamics related to heavy-ion Bragg peak radiosurgery is carried out using three-dimensional treatment planning and quantitative imaging utilizing cerebral angiography, computerized tomography (CT), magnetic resonance imaging (MRI), cine-CT, xenon X-ray CT and positron emission tomography (PET). Also under examination are the physical properties of narrow heavy-ion beams for improving methods of dose delivery and dose distribution and for establishing clinical RBE/LET and dose-response relationships for human CNS tissues. Based on the evaluation and treatment with stereotactically directed narrow beams of heavy charged particles of over 300 patients, with cerebral angiography, CT scanning and MRI and PET scanning of selected patients, plus extensive clinical and neuroradiological followup, it appears that Stereotactic charged-particle Bragg peak radiosurgery obliterates intracranial arteriovenous malformations or protects against rebleeding with reduced morbidity and no mortality. Discussion will include the method of evaluation, the clinical research protocol, the Stereotactic neuroradiological preparation, treatment planning, the radiosurgery procedure and the protocol for followup. Emphasis will be placed on the neurological results, including the neuroradiological and clinical response and early and late delayed injury in brain leading to complications (including vasogenic edema

  18. Reconstruction of negative hydrogen ion beam properties from beamline diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Ruf, Benjamin

    2014-09-25

    For the experimental fusion reactor ITER, which should show the feasibility of sustaining a fusion plasma with a positive power balance, some technology still has to be developed, amongst others also the plasma heating system. One heating technique is the neutral beam injection (NBI). A beam of fast deuterium atoms is injected into the fusion plasma. By heavy particle collisions the beam particles give their energy to the plasma. A NBI system consists of three major components. First, deuterium ions are generated in a low temperature, low pressure plasma of an ion source. At ITER, the requirements on the beam energy of 1 MeV cause the necessity of negative charged deuterium ions. Secondly, the ions are accelerated within an acceleration system with several grids, where the plasma grid is the first grid. The grids are on different descending high voltage potentials. The source itself is on the highest negative potential. Thirdly, the fast deuterium ions have to be neutralised. This thesis deals with the second step in the mentioned beam system, the ion acceleration and beam formation. The underlying experiments and measurements were carried out at the testbeds BATMAN (BAvarianTest MAchine for Negative ions) and ELISE (Extraction from a Large Ion Source Experiment) at the Max-Planck-Institut fuer Plasmaphysik Garching (IPP Garching). The main goal of this thesis is to provide a tool which allows the determination of the beam properties. These are beam divergence, stripping losses and beam inhomogeneity. For this purpose a particle trajectory code has been developed from scratch, namely BBC-NI (Bavarian Beam Code for Negative Ions). The code is able to simulate the whole beam and the outcome of several beam diagnostic tools. The data obtained from the code together with the measurements of the beam diagnostic tools should allow the reconstruction of the beam properties. The major beam diagnostic tool, which is used in this thesis, is the beam emission spectroscopy

  19. Production of negatively charged radioactive ion beams

    Science.gov (United States)

    Liu, Y.; Stracener, D. W.; Stora, T.

    2017-08-01

    Beams of short-lived radioactive nuclei are needed for frontier experimental research in nuclear structure, reactions, and astrophysics. Negatively charged radioactive ion beams have unique advantages and allow for the use of a tandem accelerator for post-acceleration, which can provide the highest beam quality and continuously variable energies. Negative ion beams can be obtained with high intensity and some unique beam purification techniques based on differences in electronegativity and chemical reactivity can be used to provide beams with high purity. This article describes the production of negative radioactive ion beams at the former holifield radioactive ion beam facility at Oak Ridge National Laboratory and at the CERN ISOLDE facility with emphasis on the development of the negative ion sources employed at these two facilities. ).

  20. Intense Ion Beams for Warm Dense Matter Physics

    International Nuclear Information System (INIS)

    Heimbucher, Lynn; Coleman, Joshua Eugene

    2008-01-01

    The Neutralized Drift Compression Experiment (NDCX) at Lawrence Berkeley National Laboratory is exploring the physical limits of compression and focusing of ion beams for heating material to warm dense matter (WDM) and fusion ignition conditions. The NDCX is a beam transport experiment with several components at a scale comparable to an inertial fusion energy driver. The NDCX is an accelerator which consists of a low-emittance ion source, high-current injector, solenoid matching section, induction bunching module, beam neutralization section, and final focusing system. The principal objectives of the experiment are to control the beam envelope, demonstrate effective neutralization of the beam space-charge, control the velocity tilt on the beam, and understand defocusing effects, field imperfections, and limitations on peak intensity such as emittance and aberrations. Target heating experiments with space-charge dominated ion beams require simultaneous longitudinal bunching and transverse focusing. A four-solenoid lattice is used to tune the beam envelope to the necessary focusing conditions before entering the induction bunching module. The induction bunching module provides a head-to-tail velocity ramp necessary to achieve peak axial compression at the desired focal plane. Downstream of the induction gap a plasma column neutralizes the beam space charge so only emittance limits the focused beam intensity. We present results of beam transport through a solenoid matching section and simultaneous focusing of a singly charged K + ion bunch at an ion energy of 0.3 MeV. The results include a qualitative comparison of experimental and calculated results after the solenoid matching section, which include time resolved current density, transverse distributions, and phase-space of the beam at different diagnostic planes. Electron cloud and gas measurements in the solenoid lattice and in the vicinity of intercepting diagnostics are also presented. Finally, comparisons of

  1. Ion beam processes in Si

    International Nuclear Information System (INIS)

    Holland, O.W.; Narayan, J.; Fathy, D.

    1984-07-01

    Observation of the effects of implants of energetic ions at high dose rates into Si have produced some exciting and interesting results. The mechanism whereby displacement damage produced by ions self-anneals during high dose rate implantation is discussed. It is shown that ion beam annealing (IBA) offers in certain situations unique possibilities for damage annealing. Annealing results of the near surface in Si with a buried oxide layer, formed by high dose implantation, are presented in order to illustrate the advantages offered by IBA. It is also shown that ion irradiation can stimulate the epitaxial recrystallization of amorphous overlayers in Si. The nonequilibrium alloying which results from such epitaxial processes is discussed as well as mechanisms which limit the solid solubility during irradiation. Finally, a dose rate dependency for the production of stable damage by ion irradiation at a constant fluence has been observed. For low fluence implants, the amount of damage is substantially greater in the case of high flux rather than low flux implantation

  2. Doublet III neutral beam multi-stream command language system

    International Nuclear Information System (INIS)

    Campbell, L.; Garcia, J.R.

    1983-01-01

    A multi-stream command language system was developed to provide control of the dual source neutral beam injectors on the Doublet III experiment at GA Technologies Inc. The Neutral Beam command language system consists of three parts: compiler, sequencer, and interactive task. The command language, which was derived from the Doublet III tokamak command language, POPS, is compiled, using a recursive descent compiler, into reverse polish notation instructions which then can be executed by the sequencer task. The interactive task accepts operator commands via a keyboard. The interactive task directs the operation of three input streams, creating commands which are then executed by the sequencer. The streams correspond to the two sources within a Doublet III neutral beam, plus an interactive stream. The sequencer multiplexes the execution of instructions from these three streams. The instructions include reads and writes to an operator terminal, arithmetic computations, intrinsic functions such as CAMAC input and output, and logical instructions. The neutral beam command language system was implemented using Modular Computer Systems (ModComp) Pascal and consists of two tasks running on a ModComp Classic IV computer. The two tasks, the interactive and the sequencer, run independently and communicate using shared memory regions. The compiler runs as an overlay to the interactive task when so directed by operator commands. The system is succesfully being used to operate the three neutral beams on Doublet III

  3. Spectroscopy of transient neutral species via negative ion photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, A.

    1991-12-01

    Negative ion photoelectron spectroscopy has been used to study two types of transient neutral species: bound free radicals (NO{sub 2} and NO{sub 3}) and unstable neutral species ((IHI) and (FH{sub 2})). The negative ion time-of-flight photoelectron spectrometer used for these experiments is described in detail.

  4. Spectroscopy of transient neutral species via negative ion photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, Alexandra [Univ. of California, Berkeley, CA (United States)

    1991-12-01

    Negative ion photoelectron spectroscopy has been used to study two types of transient neutral species: bound free radicals (NO2 and NO3) and unstable neutral species ([IHI] and [FH2]). The negative ion time-of-flight photoelectron spectrometer used for these experiments is described in detail.

  5. Development of a high current 60 keV neutral lithium beam injector for beam emission spectroscopy measurements on fusion experiments

    Science.gov (United States)

    Anda, G.; Dunai, D.; Lampert, M.; Krizsanóczi, T.; Németh, J.; Bató, S.; Nam, Y. U.; Hu, G. H.; Zoletnik, S.

    2018-01-01

    A 60 keV neutral lithium beam system was designed and built up for beam emission spectroscopy measurement of edge plasma on the KSTAR and EAST tokamaks. The electron density profile and its fluctuation can be measured using the accelerated lithium beam-based emission spectroscopy system. A thermionic ion source was developed with a SiC heater to emit around 4-5 mA ion current from a 14 mm diameter surface. The ion optic is following the 2 step design used on other devices with small modifications to reach about 2-3 cm beam diameter in the plasma at about 4 m from the ion source. A newly developed recirculating sodium vapour neutralizer neutralizes the accelerated ion beam at around 260-280 °C even during long (manipulation techniques are applied to allow optimization, aiming, cleaning, and beam modulation. The maximum 60 keV beam energy with 4 mA ion current was successfully reached at KSTAR and at EAST. Combined with an efficient observation system, the Li-beam diagnostic enables the measurement of the density profile and fluctuations on the plasma turbulence time scale.

  6. Power supply for plasma generator of HL-1M neutral beam injector

    International Nuclear Information System (INIS)

    Wang Detai; Qian Jiamei; Lei Guangjiu; Shun Mengda; Jiang Shaofeng; Wang Enyao; Lu Xuejun; Yang Tiehai; Wang Xuehua; Zhao Zhimin; Hao Ming; Huang Jianrong; Yu Yanqiu; Cheng Baoqiang; Wu Zhige; Sheng Ning; Hu Qingtao

    1999-01-01

    The diagram of the HL-1M Neutral Beam Injector (NBI) and the power supply (PS) system is shown. The NBI consists of ion source, beam line and power supply system etc. The ion source includes plasma generator and three-electrode extraction system. The power supply for plasma generator consists of a filament PS, an arc PS and gas valve PS. Testing has shown that the PS for plasma generator of the HL-1M NBI has excellent stability and obtain good plasma heating effect

  7. Neutral beam injection optimization at TJ-II

    International Nuclear Information System (INIS)

    Fuentes, C.; Liniers, M.; Wolfers, G.; Alonso, J.; Marcon, G.; Carrasco, R.; Guasp, J.; Acedo, M.; Sanchez, E.; Medrano, M.; Garcia, A.; Doncel, J.; Alejaldre, C.; Tsai, C.C.; Barber, G.; Sparks, D.

    2005-01-01

    Neutral beam injection (NBI) heating has been used on the TJ-II stellarator for the first time. The beam has a port-through power between 200 and 400 kW and injection energy 28 kV. Beam transmission is limited by beam interception at the injection port and the first toroidal field coil, therefore, beam steering optimization is of critical importance. The beam interaction areas inside TJ-II vacuum chamber are surveyed by infrared thermography. Beam reionization can be a problem due to the presence of residual gas in the duct region. Halpha emission is used to monitor the reionization at the duct. A careful optimization of the injected gas has been carried out

  8. Unstable Electrostatic Ion Cyclotron Waves Exited by an Ion Beam

    DEFF Research Database (Denmark)

    Michelsen, Poul; Pécseli, Hans; Juul Rasmussen, Jens

    1976-01-01

    Electrostatic ion cyclotron waves were observed in a quiescent cesium plasma into which a low‐energy beam of sodium ions was injected. The instability appeared when the beam velocity was above 12 times the ion thermal velocity. The waves propagated along the magnetic field with a velocity somewhat...

  9. ECR ion source based low energy ion beam facility

    Indian Academy of Sciences (India)

    Mass analyzed highly charged ion beams of energy ranging from a few keV to a few MeV plays an important role in various aspects of research in modern physics. In this paper a unique low energy ion beam facility (LEIBF) set up at Nuclear Science Centre (NSC) for providing low and medium energy multiply charged ion ...

  10. Performance of the PDX neutral beam wall armor

    International Nuclear Information System (INIS)

    Kugel, H.W.; Eubank, H.P.; Kozub, T.A.; Williams, M.D.

    1985-02-01

    The PDX wall armor was designed to function as an inner wall thermal armor, a neutral beam diagnostic, and a large area inner toroidal plasma limiter. In this paper we discuss its thermal performance as wall armor during two years of PDX neutral beam heating experiments. During this period it provided sufficient inner wall protection to permit perpendicular heating injections into normal and disruptive plasmas as well as injections in the absence of plasma involving special experiments, calibrations, and tests important for the optimization and development of the PDX neutral beam injection system. Many of the design constraints and performance issues encountered in this work are relevant to the design of larger fusion devices

  11. Heating efficiency of high-power perpendicular neutral-beam injection in PDX

    International Nuclear Information System (INIS)

    Hawryluk, R.J.; Arunasalam, V.; Bell, M.

    1982-03-01

    The heating efficiency of high power (up to 7.2 MW) near-perpendicular neutral beam injection in the PDX tokamak is comparable to that of tangential injection in PLT. Collisionless plasmas with central ion temperatures up to 6.5 keV and central electron temperatures greater than 2.5 keV have been obtained. The plasma pressure, including the contribution from the beam particles, increases with increasing beam power and does not appear to saturate, although the parametric dependence of the energy confinement time is different from that observed in ohmic discharges

  12. Design issues of radioactive ion beam facilities

    International Nuclear Information System (INIS)

    Lieuvin, M.

    1996-01-01

    There is an increasing interest in Radioactive Ion Beams throughout the world. These ions open new domains of research for nuclear physics, nuclear astrophysics and atomic physics. Two methods are used for the production of these beams: fragmentation of a primary, high energy heavy ion beam passing through a thin target or nuclei production in a thick target bombarded either by a heavy ion beam, a proton beam or by neutrons. When radioactive species are produced in a thick target, they must be extracted, ionised, separated, identified and finally accelerated. This requires a radioactive ion source, a mass separator and a post accelerator. This paper reviews these two methods, their respective domains and the specific problems related to the control and the accelerator of radioactive ion beams. (author). 39 refs., 3 figs., 2 tabs

  13. The effect of a single blade limiter on energetic neutral beam particles in Doublet III

    International Nuclear Information System (INIS)

    Petrie, T.W.; Armentrout, C.; Burrell, K.H.; Hino, T.; Kahn, C.; Kim, J.; Lohr, J.; Rottler, L.; Schissel, D.; St John, H.

    1984-01-01

    Energetic beam ion collisions with the main limiter can be a significant power loss process under certain operating conditions in Doublet III. Futhermore, these collisions may cause measurable damage to the limiter itself. Under low current and low toroidal field conditions (e.g., Isub(p) = 290 kA and Bsub(T) = 6.3 kG), 20-38% of the inferred absorbed beam power may be deposited directly on the ion drift side of the limiter by the beam ions. However, for higher plasma current and toroidal fields (e.g., Isub(p) = 480 kA and Bsub(t) = 15 kG), the fraction of inferred absorbed beam power deposited on the limiter is reduced to < 10%. Monte Carlo code simulations show that this loss of beam power is primarily a result of the large poloidal and toroidal gyro-orbits of the energetic beam ions. Other factors which may enhance beam ion losses to the limiter are (1) large separation distances between the primary limiter and the (outboard) vacuum vessel wall, and (2) plasma density buildup near the plasma edge during high gas puff operation. In addition, our data suggests enhanced plasma density and recycling near the limiter. This localized density can cause appreciable premature ionizations of the incoming beam neutrals and thus reduce the effective plasma heating of the beamline which is immediately upcurrent of the limiter. The prematurely-ionized beam particles from this adjacent beamline are responsible for much of the damage to the ion drift side of the limiter. We have found that under certain operating conditions (1) the direct beam heating of the limiter is 50% greater and (2) the stored plasma energy is 10% less when the beamline immediately upcurrent of the limiter heats the plasma. Thus, the relative positions of the limiters to the beamlines are important in designing future tokamaks. (orig.)

  14. Pulse line ion accelerator based design for the neutralized drift chamber experiment

    Science.gov (United States)

    Ling, C. Y.; Yu, S. S.; Henestroza, E.; Grote, D. P.; Friedman, A.

    2009-04-01

    The pulse line ion accelerator (PLIA) is a promising approach to accelerating heavy ion beams to regimes of interest for the study of high energy density physics (HEDP) and warm dense matter in a cost effective way. In this paper we demonstrate a PLIA-based design for a proposed HEDP machine, the neutralized drift compression experiment II. The simulation results from the injector to the exit of the accelerator using the particle-in-cell code WARP are presented. We show how the traveling wave structure of PLIA suggests straightforward strategies in controlling the longitudinal and transverse dynamics of the ion beam.

  15. Design of the ITER (International Thermonuclear Experimental Reactor) neutral beam system beamline, United States concept

    International Nuclear Information System (INIS)

    Purgalis, P.; Anderson, O.A.; Cooper, W.S.; DeVries, G.E.; Lietzke, A.F.; Kunkel, W.B.; Kwan, J.W.; Matuk, C.A.; Nakai, T.; Stearns, J.W.; Soroka, L.; Wells, R.P.; Lindquist, W.B.; Neef, W.S.; Reginato, L.L.; Sedgley, D.W.; Brook, J.W.; Luzzi, T.E.; Myers, T.J.

    1989-01-01

    Design of a neutral beamline for ITER (International Thermonuclear Experimental Reactor) is described. The design incorporates a barium surface conversion D - source feeding a linear array of accelerator channels. The system uses a dc accelerator with electrostatic quadrupoles for strong focusing. A high voltage power supply that is integrated with the accelerator is presented as an attractive option. A gas neutralizer is used and residual ions exiting the neutralizer are deflected to watercooled dumps. Cryopanels are located at the accelerator exit to pump excess gas from the source and the neutralizer, and in the ion dump cavity to pump re-neutralized ions and neutralizer gas. All the above components are packaged in compact identical, independent modules that can be removed for remote maintenance. The neutral beam system delivers 75 MW of D degree into three ports with a total of nine modules arranged in stacks of three modules per port. To increase reliability each module is designed to deliver up to 10 MW at 1.3 MeV; this allows eight modules operating at partial capacity to deliver the required power in the event one module is removed from service. Radiation protection is provided by shielding and by locating critical components in the source and accelerator 35 m from the port into the torus. Neutron shielding in the drift duct provides the added feature of limiting conductance and thus reducing gas flow to and from the torus. Alternative component choices are also discussed for the evolving design. 8 refs., 4 figs., 1 tab

  16. Studies on ion scattering and sputtering processes relevant to ion beam sputter deposition of multicomponent thin films

    International Nuclear Information System (INIS)

    Auciello, O.; Ameen, M.S.; Kingon, A.I.

    1989-01-01

    Results from computer simulation and experiments on ion scattering and sputtering processes in ion beam sputter deposition of high Tc superconducting and ferroelectric thin films are presented. It is demonstrated that scattering of neutralized ions from the targets can result in undesirable erosion of, and inert gas incorporation in, the growing films, depending on the ion/target atom ass ratio and ion beam angle of incidence/target/substrate geometry. The studies indicate that sputtering Kr + or Xe + ions is preferable to the most commonly used Ar + ions, since the undesirable phenomena mentioned above are minimized for the first two ions. These results are used to determine optimum sputter deposition geometry and ion beam parameters for growing multicomponent oxide thin films by ion beam sputter-deposition. 10 refs., 5 figs

  17. Characterisation of neutral hydrogen beam by means of active balmer-a-spectroscopy

    International Nuclear Information System (INIS)

    Wachter, C.

    1999-01-01

    Neutral particle beams are used in thermal nuclear experiments for plasma heating and current drive, and as a diagnostic tool for active spectroscopy. Within the frame of this thesis eight viewing lines for H α -spectroscopy have been installed at the end of the injector to observe the fully established neutral beam. The viewing lines are all parallel to the horizontal plane and include small angles with the beam axis, in order to make use of the Doppler effect which separates the signals from the three energy components from each other and from the H α -emission of the thermal particles. A multi-Gaussian fit code has been applied to give the amplitudes, positions and widths of the Gauss shaped signals. From this data, the beam composition and, including the physics processes in the acceleration and neutralisation sections, the ion species fractions in the source have been calculated. Furthermore, the vertical density profile and an estimation of the absolute particle density distribution based on an absolute calibration resulted. From the line positions the exact acceleration voltage has been obtained. The line widths allow an estimate of the horizontal divergence. During this work, two ion sources, the 'Pagoda' and the 'Sourcette', have been investigated to obtain the ion species ratio and beam profile. The comparison of the spectroscopic with the calorimetric results gives a useful insight into the beam steering geometry. (author)

  18. Characterisation of neutral hydrogen beam by means of active balmer-a-spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Wachter, C

    1999-01-01

    Neutral particle beams are used in thermal nuclear experiments for plasma heating and current drive, and as a diagnostic tool for active spectroscopy. Within the frame of this thesis eight viewing lines for H{sub {alpha}}-spectroscopy have been installed at the end of the injector to observe the fully established neutral beam. The viewing lines are all parallel to the horizontal plane and include small angles with the beam axis, in order to make use of the Doppler effect which separates the signals from the three energy components from each other and from the H{sub {alpha}}-emission of the thermal particles. A multi-Gaussian fit code has been applied to give the amplitudes, positions and widths of the Gauss shaped signals. From this data, the beam composition and, including the physics processes in the acceleration and neutralisation sections, the ion species fractions in the source have been calculated. Furthermore, the vertical density profile and an estimation of the absolute particle density distribution based on an absolute calibration resulted. From the line positions the exact acceleration voltage has been obtained. The line widths allow an estimate of the horizontal divergence. During this work, two ion sources, the 'Pagoda' and the 'Sourcette', have been investigated to obtain the ion species ratio and beam profile. The comparison of the spectroscopic with the calorimetric results gives a useful insight into the beam steering geometry. (author)

  19. Implementation of a quasi-realtime display of DIII-D neutral beam heating waveforms

    International Nuclear Information System (INIS)

    Phillips, J.C.

    1993-10-01

    The DIII-D neutral beam system employs eight 80 keV ion sources mounted on four beamlines to provide plasma heating to the DIII-D tokamak. The neutral beam system is capable of injecting over 20 MW of deuterium power with flexibility in terms of timing and modulation of the individual neutral beams. To maintain DIII-D's efficient tokamak shot cycle and make informed control decisions, it is important to be able to determine which beams fired, and exactly when, by the time the tokamak shot is over. Previously this information was available in centralized form only after a several minute wait. A cost-effective alternative to the traditional eight-channel storage oscilloscope has been implemented using off the shelf PC hardware and software. The system provides a real time display of injected neutral beam accelerator voltages and tokamak plasma current, as well an a summation waveform indicative of the total injected power as a function of time. The hardware consists of a Macintosh Centris 650 PC with a Motorola 68040 microprocessor. Data acquisition is accomplished using a National Instrument's 16-channel analog to digital conversion board for the Macintosh. The color displays and functionality were developed using National Instruments' LabView environment. Because the price of PCs has been decreasing rapidly and their capabilities increasing, this system is far less expensive than an eight-channel storage oscilloscope. As a flexible combination of PC and software, the system also provides much more capability than a dedicated oscilloscope, acting as the neutral beam coordinator's logbook, recording comments and availability statistics. Data such as shot number and neutral beam parameters are obtained over the local network from other computers and added to the display. Waveforms are easily archived to disk for future recall. Details of the implementation will be discussed along with samples of the displays and a description of the system's function and capabilities

  20. Implementation of a quasi-realtime display of DIII-D neutral beam heating waveforms

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, J.C.

    1993-10-01

    The DIII-D neutral beam system employs eight 80 keV ion sources mounted on four beamlines to provide plasma heating to the DIII-D tokamak. The neutral beam system is capable of injecting over 20 MW of deuterium power with flexibility in terms of timing and modulation of the individual neutral beams. To maintain DIII-D`s efficient tokamak shot cycle and make informed control decisions, it is important to be able to determine which beams fired, and exactly when, by the time the tokamak shot is over. Previously this information was available in centralized form only after a several minute wait. A cost-effective alternative to the traditional eight-channel storage oscilloscope has been implemented using off the shelf PC hardware and software. The system provides a real time display of injected neutral beam accelerator voltages and tokamak plasma current, as well an a summation waveform indicative of the total injected power as a function of time. The hardware consists of a Macintosh Centris 650 PC with a Motorola 68040 microprocessor. Data acquisition is accomplished using a National Instrument`s 16-channel analog to digital conversion board for the Macintosh. The color displays and functionality were developed using National Instruments` LabView environment. Because the price of PCs has been decreasing rapidly and their capabilities increasing, this system is far less expensive than an eight-channel storage oscilloscope. As a flexible combination of PC and software, the system also provides much more capability than a dedicated oscilloscope, acting as the neutral beam coordinator`s logbook, recording comments and availability statistics. Data such as shot number and neutral beam parameters are obtained over the local network from other computers and added to the display. Waveforms are easily archived to disk for future recall. Details of the implementation will be discussed along with samples of the displays and a description of the system`s function and capabilities.

  1. Neutral beam heating in stellarators: a numerical approach

    International Nuclear Information System (INIS)

    Hokin, S.A.; Rome, J.A.; Hender, T.C.; Fowler, R.H.

    1983-03-01

    Calculation of neutral beam deposition and heating in stellarators is complicated by the twisty stellarator geometry and by the usual beam focusing, divergence, and cross-sectional shape considerations. A new deposition code has been written that takes all of this geometry into account. A unique feature of this code is that it gives particle deposition in field-line coordinates, enabling the thermalization problem to be solved more efficiently

  2. The Heidelberg CSR: Stored Ion Beams in a Cryogenic Environment

    International Nuclear Information System (INIS)

    Wolf, A.; Hahn, R. von; Grieser, M.; Orlov, D. A.; Fadil, H.; Welsch, C. P.; Andrianarijaona, V.; Diehl, A.; Schroeter, C. D.; Crespo Lopez-Urrutia, J. R.; Weber, T.; Mallinger, V.; Schwalm, D.; Ullrich, J.; Rappaport, M.; Urbain, X.; Haberstroh, Ch.; Quack, H.; Zajfman, D.

    2006-01-01

    A cryogenic electrostatic ion storage ring CSR is under development at the Max-Planck Institute for Nuclear Physics in Heidelberg, Germany. Cooling of the ultrahigh vacuum chamber is envisaged to lead to extremely low pressures as demonstrated by cryogenic ion traps. The ring will apply electron cooling with electron beams of a few eV up to 200 eV. Through long storage times of 1000 s as well as through the low wall temperature, internal cooling of infrared-active molecular ions to their rotational ground state will be possible and their collisions with merged collinear beams of electrons and neutral atoms can be detected with high energy resolution. In addition storage of slow highly charged ions is foreseen. Using a fixed in-ring gas target and a reaction microscope, collisions of the stored ions at a speed of the order of the atomic unit can be kinematically reconstructed. The layout and the cryogenic concept are introduced

  3. A cooler for intense low-energy ion beams

    International Nuclear Information System (INIS)

    Varentsov, V.L.; Habs, D.

    2002-01-01

    A new efficient cooling technique for intense low-energy ion beams is explored. The primary ions are directly injected through a converging-diverging nozzle into a cold expanding supersonic He carrier gas jet. There they adopt the temperature and overall velocity of the gas jet, creating an e - He + plasma in the slowing down process. In the RF-funnel that is placed on axis in the immediate vicinity of the nozzle exit plane the He + ions and electrons penetrate into the funnel walls and the He + ions have neutralized, while the desired more heavy ions are confined and focused inside the funnel. After reducing the plasma to a small level in the funnel the ion beam is further purified and compressed passing through a RFQ channel. Finally, the cooled low-emittance ion beam is extracted into high vacuum conditions through the skimmer placed behind the RFQ channel. The operation of the new ion beam cooling technique has been studied by means of numerical simulations. The results of calculations are presented

  4. A cooler for intense low-energy ion beams

    CERN Document Server

    Varentsov, V L

    2002-01-01

    A new efficient cooling technique for intense low-energy ion beams is explored. The primary ions are directly injected through a converging-diverging nozzle into a cold expanding supersonic He carrier gas jet. There they adopt the temperature and overall velocity of the gas jet, creating an e sup - He sup + plasma in the slowing down process. In the RF-funnel that is placed on axis in the immediate vicinity of the nozzle exit plane the He sup + ions and electrons penetrate into the funnel walls and the He sup + ions have neutralized, while the desired more heavy ions are confined and focused inside the funnel. After reducing the plasma to a small level in the funnel the ion beam is further purified and compressed passing through a RFQ channel. Finally, the cooled low-emittance ion beam is extracted into high vacuum conditions through the skimmer placed behind the RFQ channel. The operation of the new ion beam cooling technique has been studied by means of numerical simulations. The results of calculations are...

  5. Charge-exchange and fusion reaction measurements during compression experiments with neutral beam heating in the Tokamak Fusion Test Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kaita, R.; Heidbrink, W.W.; Hammett, G.W.; Chan, A.A.; England, A.C.; Hendel, H.W.; Medley, S.S.; Nieschmidt, E.; Roquemore, A.L.; Scott, S.D.

    1986-04-01

    Adiabatic toroidal compression experiments were performed in conjunction with high power neutral beam injection in the Tokamak Fusion Test Reactor (TFTR). Acceleration of beam ions to energies nearly twice the injection energy was measured with a charge-exchange neutral particle analyzer. Measurements were also made of 2.5 MeV neutrons and 15 MeV protons produced in fusion reactions between the deuterium beam ions and the thermal deuterium and /sup 3/He ions, respectively. When the plasma was compressed, the d(d,n)/sup 3/He fusion reaction rate increased a factor of five, and the /sup 3/He(d,p)/sup 4/He rate by a factor of twenty. These data were simulated with a bounce-averaged Fokker-Planck program, which assumed conservation of angular momentum and magnetic moment during compression. The results indicate that the beam ion acceleration was consistent with adiabatic scaling.

  6. Charge-exchange and fusion reaction measurements during compression experiments with neutral beam heating in the Tokamak Fusion Test Reactor

    International Nuclear Information System (INIS)

    Kaita, R.; Heidbrink, W.W.; Hammett, G.W.

    1986-04-01

    Adiabatic toroidal compression experiments were performed in conjunction with high power neutral beam injection in the Tokamak Fusion Test Reactor (TFTR). Acceleration of beam ions to energies nearly twice the injection energy was measured with a charge-exchange neutral particle analyzer. Measurements were also made of 2.5 MeV neutrons and 15 MeV protons produced in fusion reactions between the deuterium beam ions and the thermal deuterium and 3 He ions, respectively. When the plasma was compressed, the d(d,n) 3 He fusion reaction rate increased a factor of five, and the 3 He(d,p) 4 He rate by a factor of twenty. These data were simulated with a bounce-averaged Fokker-Planck program, which assumed conservation of angular momentum and magnetic moment during compression. The results indicate that the beam ion acceleration was consistent with adiabatic scaling

  7. Ion-Beam-Excited Electrostatic Ion Cyclotron Waves

    DEFF Research Database (Denmark)

    Michelsen, Poul; Pécseli, Hans; Juul Rasmussen, Jens

    1976-01-01

    Self-excited electrostatic ion cyclotron waves were observed in an ion-beam-plasma system produced in a DP-operated Q-machine. The frequency of the waves showed the theoretically predicted variation with the magnetic field.......Self-excited electrostatic ion cyclotron waves were observed in an ion-beam-plasma system produced in a DP-operated Q-machine. The frequency of the waves showed the theoretically predicted variation with the magnetic field....

  8. Analytic Scalings of the Constant-Neutralization Beam Envelope Equation, with Applications

    International Nuclear Information System (INIS)

    McCarrick, J F

    2007-01-01

    Neutralized transport of relativistic electron beams can achieved in various circumstances. In one form, the beam is transported through a plasma, either pre-formed or beam generated, where the plasma electrons are ejected due to the space charge influence of the beam. The beam can be fully neutralized this way if the plasma is sufficiently dense. Typically, the transport physics of concern in this case are the various macro- and micro-instabilities that can develop due to interactions of the beam with the plasma; charge and current neutralization are certainly important but tend to be just one set of concerns among many. The study of beam/plasma interactions has been active for many years [e.g. 1]. In a different scenario, the beam impinges on a plasma with a sharp boundary (as maintained on the timescale of a beam pulse) and, via space charge, extracts ions from the plasma; extraction energies can be hundreds of kilovolts in the case of tightly focused, high current beams. In this case, the ions have a lower density than the beam and are not accompanied by a plasma electron population; the main transport issue is charge neutralization. Such a sharply bounded plasma can occur via ionization of surface impurities from a solid target; the transport of the beam through this thin layer is typically not of interest relative to the transport upstream of the surface and the beam/target interactions beyond the surface. Since the partial neutralization of the beam changes its focusing characteristics on the target, and since the high extraction energy means the ion column is moving rapidly into the beam and introducing strong time variation, this 'backstreaming ion' phenomenon has been an area of active study in the transport of the high-intensity electron beams used in radiographic accelerators (see [2] for an example of such machines). However, much of the work has been experimental [3] and numerical [4]. The conceptual understanding provided by pencil-and-paper analysis

  9. Neutral beam heating of the TFTR vacuum vessel protective plates

    Energy Technology Data Exchange (ETDEWEB)

    Sink, D.A.

    1976-04-01

    The transmission of neutral beams through plasmas expected in the Tokamak Fusion Test Reactor (TFTR) has been investigated. An analytical expression for the transmission coefficient of a 120 keV deuterium beam through a tritium plasma was used and a model for the flux profile of the TFTR Neutral Beam System designed by LBL/LLL was developed and incorporated. The plasma is assumed to have a parabolic profile and is characterized by a major radius of 310 cm, a minor radius of 57 cm, and a central plasma density of greater than or equal to 0.4 x 10/sup 14/ cm-/sup 3/. To protect the stainless steel vacuum vessel walls of the TFTR device, tungsten plates are located inside the vessel. The loading of the tungsten protective plates during normal operation is well below the neutral beam fluxes which would melt the tungsten. The TFTR Neutral Beam System will inject a total of 20 MW of 120 keV deuterium atoms from twelve sources, as well as approximately 12 MW of 60 keV deuterium atoms. The fluxes anticipated on the tungsten plates due to an unattenuated beam which would be incident at an angle of 45/sup 0/ are less than or equal to 6.5 kW/cm/sup 2/. The fluxes due to an attenuated beam are calculated to be less than or equal to 0.35 kW/cm/sup 2/. For the maximum injection time of 0.5 second, a fault condition in which the plasma was not formed at the time of injection could induce a surface temperature very near the melting point of tungsten. For the standard 0.1 second injection time anticipated for TFTR, a similar fault condition would not cause the temperature to rise to more than 2000 K which is well below the melting point (3640 K) of tungsten.

  10. Evaluation of beam divergence of a negative hydrogen ion beam using Doppler shift spectroscopy diagnostics

    Science.gov (United States)

    Deka, A. J.; Bharathi, P.; Pandya, K.; Bandyopadhyay, M.; Bhuyan, M.; Yadav, R. K.; Tyagi, H.; Gahlaut, A.; Chakraborty, A.

    2018-01-01

    The Doppler Shift Spectroscopy (DSS) diagnostic is in the conceptual stage to estimate beam divergence, stripping losses, and beam uniformity of the 100 keV hydrogen Diagnostics Neutral Beam of International Thermonuclear Experimental Reactor. This DSS diagnostic is used to measure the above-mentioned parameters with an error of less than 10%. To aid the design calculations and to establish a methodology for estimation of the beam divergence, DSS measurements were carried out on the existing prototype ion source RF Operated Beam Source in India for Negative ion Research. Emissions of the fast-excited neutrals that are generated from the extracted negative ions were collected in the target tank, and the line broadening of these emissions were used for estimating beam divergence. The observed broadening is a convolution of broadenings due to beam divergence, collection optics, voltage ripple, beam focusing, and instrumental broadening. Hence, for estimating the beam divergence from the observed line broadening, a systematic line profile analysis was performed. To minimize the error in the divergence measurements, a study on error propagation in the beam divergence measurements was carried out and the error was estimated. The measurements of beam divergence were done at a constant RF power of 50 kW and a source pressure of 0.6 Pa by varying the extraction voltage from 4 kV to10 kV and the acceleration voltage from 10 kV to 15 kV. These measurements were then compared with the calorimetric divergence, and the results seemed to agree within 10%. A minimum beam divergence of ˜3° was obtained when the source was operated at an extraction voltage of ˜5 kV and at a ˜10 kV acceleration voltage, i.e., at a total applied voltage of 15 kV. This is in agreement with the values reported in experiments carried out on similar sources elsewhere.

  11. Consequences of trapped beam ions of the analysis of neutron emission data

    International Nuclear Information System (INIS)

    Loughlin, M.J.; Hone, M.; Jarvis, O.N.; Laundy, B.; Sadler, G.; Belle, P. van

    1989-01-01

    Neutron energy spectra have been measured during D o neutral beam heating of deuterium plasmas. The thermonuclear to beam-plasma neutron production ratios are deduced. For a non-radial spectrometer line-of-sight, the trapped beam-ion fraction must be considered. (author) 5 refs., 4 figs

  12. Beam structure studies of low-energy ion beams

    Science.gov (United States)

    Saadatmand, K.; Schneider, J. D.; Geisik, C.; Stevens, R. R.

    1991-05-01

    The ion beam structure at various axial positions along the beam-transport line has been monitored and studied utilizing a fluor screen and a video camera. The fluor material is aluminum oxide that is plasma-jet sprayed onto the surface of an aluminum or a water-cooled copper substrate. The visual representation of the beam structure is digitized and enhanced through use of false-color coding and displayed on a TV monitor for the on-line viewing by the experimentalist. Digitized video signals are stored for further off-line processing and extracting more information about the beam, such as beam profiles. This inexpensive and effective diagnostic enables the experimentalist to observe the real-time beam response (such as evolution of the beam structure, shifts in the beam intensity at various spatial locations within the beam perimeter, and shifts in the beam center and position) to parameter changes.

  13. A large ion beam device for laboratory solar wind studies

    Science.gov (United States)

    Ulibarri, Zach; Han, Jia; Horányi, Mihály; Munsat, Tobin; Wang, Xu; Whittall-Scherfee, Guy; Yeo, Li Hsia

    2017-11-01

    The Colorado Solar Wind Experiment is a new device constructed at the Institute for Modeling Plasma, Atmospheres, and Cosmic Dust at the University of Colorado. A large cross-sectional Kaufman ion source is used to create steady state plasma flow to model the solar wind in an experimental vacuum chamber. The plasma beam has a diameter of 12 cm at the source, ion energies of up to 1 keV, and ion flows of up to 0.1 mA/cm2. Chamber pressure can be reduced to 4 × 10-5 Torr under operating conditions to suppress ion-neutral collisions and create a monoenergetic ion beam. The beam profile has been characterized by a Langmuir probe and an ion energy analyzer mounted on a two-dimensional translation stage. The beam profile meets the requirements for planned experiments that will study solar wind interaction with lunar magnetic anomalies, the charging and dynamics of dust in the solar wind, plasma wakes and refilling, and the wakes of topographic features such as craters or boulders. This article describes the technical details of the device, initial operation and beam characterization, and the planned experiments.

  14. Radiation effects of ion beams on polymers

    International Nuclear Information System (INIS)

    Tagawa, Seiichi

    1993-01-01

    Recent progress in the radiation effects of ion beams on polymers are reviewed briefly. Our recent work on the radiation effects of ion beams on polystyrene thin films on silicon wafers and time resolved emission studies on polymers are described. (orig.)

  15. Heavy ion beams for inertial fusion

    Energy Technology Data Exchange (ETDEWEB)

    Godlove, T.F.; Herrmannsfeldt, W.B.

    1980-05-01

    The United States' program in inertial confinement fusion (ICF) is described in this paper, with emphasis on the studies of the use of intense high energy beams of heavy ions to provide the power and energy needed to initiate thermonuclear burn. Preliminary calculations of the transport of intense ion beams in an electrostatic quadrupole focussing structure are discussed.

  16. 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

  17. High power 1 MeV neutral beam system and its application plan for the international tokamak experimental reactor

    Energy Technology Data Exchange (ETDEWEB)

    Hemsworth, R.S. [ITER Joint Central Team, Naka, Ibaraki (Japan)

    1997-03-01

    This paper describes the Neutral Beam Injection system which is presently being designed for the International Tokamak Experimental Reactor, ITER, in Europe Japan and Russia, with co-ordination by the Joint Central Team of ITER at Naka, Japan. The proposed system consists of three negative ion based neutral injectors, delivering a total of 50 MW of 1 MeV D{sup 0} to the ITER plasma for a pulse length of >1000 s. Each injectors uses a single caesiated volume arc discharge negative ion source, and a multi-grid, multi-aperture accelerator, to produce about 40 A of 1 MeV D{sup -}. This will be neutralized by collisions with D{sub 2} in a sub-divided gas neutralizer, which has a conversion efficiency of about 60%. The charged fraction of the beam emerging from the neutralizer is dumped in an electrostatic residual ion dump. A water cooled calorimeter can be moved into the beam path to intercept the neutral beam, allowing commissioning of the injector independent of ITER. ITER is scheduled to produce its first plasma at the beginning of 2008, and the planning of the R and D, construction and installation foresees the neutral injection system being available from the start of ITER operations. (author)

  18. Guidelines for Remote Handling Maintenance of ITER Neutral Beam Components

    International Nuclear Information System (INIS)

    Cordier, J.-J.; Hemsworth, R.; Bayetti, P.

    2006-01-01

    Remote handling maintenance of ITER components is one of the main challenges of the ITER project. This type of maintenance shall be operational for the nuclear phase of exploitation of ITER, and be considered at a very early stage since it significantly impacts on the components design, interfaces management and integration business. A large part of the R/H equipment will be procured by the EU partner, in particular the whole Neutral Beam Remote Handling (RH) equipment package. A great deal of work has already been done in this field during the EDA phase of ITER project, but improvements and alternative option that are now proposed by ITER lead to added RH and maintenance engineering studies. The Neutral Beam Heating -and- Current Drive system 1 is being revisited by the ITER project. The vertical maintenance scheme that is presently considered by ITER, may significantly impact on the reference design of the Neutral Beam (NB) system and associated components and lead to new design of the NB box itself. In addition, revision of both NB cell radiation level zoning and remote handling classification of the beam line injector will also significantly impact on components design and maintenance. Based on the experience gained on the vertical maintenance scheme, developed in detail for the ITER Neutral Beam Test Facility 2 to be built in Europe in a near future, guidelines for the revision of the design and preliminary feasibility study of the remote handling vertical maintenance scheme of beam line components are described in the paper. A maintenance option for the SINGAP3 accelerator is also presented. (author)

  19. MAVEN Neutral Gas and Ion Mass Spectrometer Data

    Data.gov (United States)

    National Aeronautics and Space Administration — This bundle contains the data collected by the Neutral Gas and Ion Mass Spectrometer (NGIMS) instrument aboard the Mars Atmosphere and Volatile EvolutioN (MAVEN)...

  20. Microwave plasma source for neutral-beam injection systems. Quarterly technical progress report

    International Nuclear Information System (INIS)

    1981-01-01

    The overall program is described and the technical and programmatic reasons for the decision to pursue both the RFI and ECH sources into the current hydrogen test stage is discussed. We consider the general characteristics of plasma sources in the parameter regime of interest for neutral beam applications. The operatonal characteristics, advantages and potential problems of RFI and ECH sources are discussed. In these latter two sections we rely heavily on experience derived from developing RFI and ECH ion engine sources for NASA

  1. Beam emittance measurements on multicusp ion sources

    Energy Technology Data Exchange (ETDEWEB)

    Sarstedt, M.; Lee, Y.; Leung, K.N. [and others

    1995-08-01

    Multicusp ion sources are used for various applications. Presently, the implementation of this type of ion source planned for the development of an ion beam lithography machine, which will be used for the projection of sub-0.2 {mu}m patterns onto a wafer substrate. Since, for this application, a very good beam quality and a small ion energy spread are required, emittance measurements have been performed on a multicusp ion source for various source conditions. It is shown that the installation of proper capacitors between the extraction electrodes is necessary to avoid rf-pickup, which otherwise leads to a distortion of the beam emittance. The influence of the magnetic filter field on the beam emittance has been investigated, and the beam emittance of a dc filament-discharge plasma has also been compared to that of an rf-generated plasma.

  2. Beam emittance measurements on multicusp ion sources

    International Nuclear Information System (INIS)

    Sarstedt, M.; Lee, Y.; Leung, K.N.

    1995-08-01

    Multicusp ion sources are used for various applications. Presently, the implementation of this type of ion source planned for the development of an ion beam lithography machine, which will be used for the projection of sub-0.2 μm patterns onto a wafer substrate. Since, for this application, a very good beam quality and a small ion energy spread are required, emittance measurements have been performed on a multicusp ion source for various source conditions. It is shown that the installation of proper capacitors between the extraction electrodes is necessary to avoid rf-pickup, which otherwise leads to a distortion of the beam emittance. The influence of the magnetic filter field on the beam emittance has been investigated, and the beam emittance of a dc filament-discharge plasma has also been compared to that of an rf-generated plasma

  3. ECR ion source based low energy ion beam facility

    Indian Academy of Sciences (India)

    Abstract. Mass analyzed highly charged ion beams of energy ranging from a few keV to a few. MeV plays an important role in various aspects of research in modern physics. In this paper a unique low energy ion beam facility (LEIBF) set up at Nuclear Science Centre (NSC) for providing low and medium energy multiply ...

  4. Intense ion beams for inertial confinement fusion

    International Nuclear Information System (INIS)

    Mehlhorn, T.A.

    1997-01-01

    Intense beams of light of heavy ions are being studied as inertial confinement fusion (ICF) drivers for high yield and energy. Heavy and light ions have common interests in beam transport, targets, and alternative accelerators. Self-pinched transport is being jointly studied. This article reviews the development of intense ion beams for ICF. Light-ion drivers are highlighted because they are compact, modular, efficient and low cost. Issues facing light ions are: (1) decreasing beam divergence; (2) increasing beam brightness; and (3) demonstrating self-pinched transport. Applied-B ion diodes are favored because of efficiency, beam brightness, perceived scalability, achievable focal intensity, and multistage capability. A light-ion concept addressing these issues uses: (1) an injector divergence of ≤ 24 mrad at 9 MeV; (2) two-stage acceleration to reduce divergence to ≤ 12 mrad at 35 MeV; and (3) self-pinched transport accepting divergences up to 12 mrad. Substantial progress in ion-driven target physics and repetitive ion diode technology is also presented. Z-pinch drivers are being pursued as the shortest pulsed power path to target physics experiments and high-yield fusion. However, light ions remain the pulsed power ICF driver of choice for high-yield fusion energy applications that require driver standoff and repetitive operation. 100 refs

  5. Beam brilliance investigation of high current ion beams at GSI heavy ion accelerator facility.

    Science.gov (United States)

    Adonin, A A; Hollinger, R

    2014-02-01

    In this work the emittance measurements of high current Ta-beam provided by VARIS (Vacuum Arc Ion Source) ion source are presented. Beam brilliance as a function of beam aperture at various extraction conditions is investigated. Influence of electrostatic ion beam compression in post acceleration gap on the beam quality is discussed. Use of different extraction systems (single aperture, 7 holes, and 13 holes) in order to achieve more peaked beam core is considered. The possible ways to increase the beam brilliance are discussed.

  6. Mutation induction by ion beams in plants

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Atsushi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2001-03-01

    The effect of ion beams such as C, He, and Ne ions was investigated on the mutation induction in plants with the expectation that ion beams of high linear energy transfer (LET) can frequently produce large DNA alternation such as inversion, translocation and large deletion rather than point mutation. Mutation frequency was investigated using Arabidopsis visible phenotype loci and was 8 to 33 fold higher for 220 MeV carbon ions than for electrons. Mutation spectrum was investigated on the flower color of chrysanthemum cv to find that flower mutants induced by ion beams show complex and stripe types rather than single color. Polymerase chain reaction analysis was performed to investigate DNA alteration of mutations. In conclusion, the characteristics of ion beams for the mutation induction are 1) high frequency, 2) broad mutation spectrum, and 3) novel mutants. (S. Ohno)

  7. Magnetic Field Considerations for the Design and Location of a Diagnostic Neutral Beam Injector for the TJ-II Stellarator

    International Nuclear Information System (INIS)

    McCarthy, K. J.; Lopez Fraguas, A.; Balbin, R.

    2004-01-01

    A diagnostic neutral beam injection system is being developed for the TJ-II stellarator. The principal goal is to increase the signal-to-noise ratio and to provide spatial resolution along the plasma minor radius in Charge Exchange Recombination Spectroscopy and Neutral Particle Analysis diagnostics, while also opening up new opportunities for physics studies. After summarizing the compact diagnostic neutral beam injector system selected as well as the TJ-II vacuum vessel and coil geometry, we address the sensitivity of TJ-II magnetic configurations to the ferromagnetic materials that shield the ion source and neutralizer tubing of the neutral beam injection system using a popular approach in which the field is approximated via magnetic dipole moments, finally, the scientific and design trade-offs made to minimize the impact are discussed. (Author) 24 refs

  8. Magnetic Field Considerations for the Design and Location of a Diagnostic Neutral Beam Injector for the TJ-II Stellarator

    Energy Technology Data Exchange (ETDEWEB)

    McCarthy, K. J.; Lopez Fraguas, A.; Balbin, R.

    2004-07-01

    A diagnostic neutral beam injection system is being developed for the TJ-II stellarator. The principal goal is to increase the signal-to-noise ratio and to provide spatial resolution along the plasma minor radius in Charge Exchange Recombination Spectroscopy and Neutral Particle Analysis diagnostics, while also opening up new opportunities for physics studies. After summarizing the compact diagnostic neutral beam injector system selected as well as the TJ-II vacuum vessel and coil geometry, we address the sensitivity of TJ-II magnetic configurations to the ferromagnetic materials that shield the ion source and neutralizer tubing of the neutral beam injection system using a popular approach in which the field is approximated via magnetic dipole moments, finally, the scientific and design trade-offs made to minimize the impact are discussed. (Author) 24 refs.

  9. Constraints on ion beam handling for intersecting beam experiments

    International Nuclear Information System (INIS)

    Kruse, T.

    1981-01-01

    The intense synchrotron radiation beams from the NSLS uv or x-ray storage rings still do not compare in monochromatized photon flux with a laser beam, a fact which becomes apparent in considering reaction rates for interaction of photon and ion beams. There are two prototypical interaction geometries, parallel and perpendicular. Calculations should properly be done in the rest frame of the ion beam; however, expected beta values are small, so the lab frame will be employed and aberration and Doppler shift effects neglected

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

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Y. [Brookhaven National Laboratory (BNL), Upton, NY (United States); Fischer, W. [Brookhaven National Laboratory (BNL), Upton, NY (United States); White, S. [Brookhaven National Laboratory (BNL), Upton, NY (United States)

    2015-06-24

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

  11. Integral Transport Analysis Results for Ions Flowing Through Neutral Gas

    Science.gov (United States)

    Emmert, Gilbert; Santarius, John

    2017-10-01

    Results of a computational model for the flow of energetic ions and neutrals through a background neutral gas will be presented. The method models reactions as creating a new source of ions or neutrals if the energy or charge state of the resulting particle is changed. For a given source boundary condition, the creation and annihilation of the various species is formulated as a 1-D Volterra integral equation that can quickly be solved numerically by finite differences. The present work focuses on multiple-pass, 1-D ion flow through neutral gas and a nearly transparent, concentric anode and cathode pair in spherical, cylindrical, or linear geometry. This has been implemented as a computer code for atomic (3He, 3He +, 3He + +) and molecular (D, D2, D-, D +, D2 +, D3 +) ion and neutral species, and applied to modeling inertial-electrostatic connement (IEC) devices. The code yields detailed energy spectra of the various ions and energetic neutral species. Calculations for several University of Wisconsin IEC and ion implantation devices will be presented. Research supported by US Dept. of Homeland Security Grant 2015-DN-077-ARI095, Dept. of Energy Grant DE-FG02-04ER54745, and the Grainger Foundation.

  12. Ion and electron beam interaction on surfaces - a detection mechanism for obtaining visual ion beam images

    International Nuclear Information System (INIS)

    Fine, J.; Gorden, R. Jr.

    1978-01-01

    Two-dimensional images have been obtained of ion beam impact cross sections on solid surfaces by the coincident interaction of a rastered electron beam. This detection method is effective in producing images in real time on various insulator surfaces. The size of these images correlates well with ion beam current density profile measurements (at full width) and, therefore, can be very useful for ion beam diagnostics and alignment. (Auth.)

  13. SIPHORE: Conceptual Study of a High Efficiency Neutral Beam Injector Based on Photo-detachment for Future Fusion Reactors

    Science.gov (United States)

    Simonin, A.; Christin, L.; de Esch, H.; Garibaldi, P.; Grand, C.; Villecroze, F.; Blondel, C.; Delsart, C.; Drag, C.; Vandevraye, M.; Brillet, A.; Chaibi, W.

    2011-09-01

    An innovative high efficiency neutral beam injector concept for future fusion reactors is under investigation (simulation and R&D) between several laboratories in France, the goal being to perform a feasibility study for the neutralization of intense high energy (1 MeV) negative ion (NI) beams by photo-detachment. The objective of the proposed project is to put together the expertise of three leading groups in negative ion quantum physics, high power stabilized lasers and neutral beam injectors to perform studies of a new injector concept called SIPHORE (SIngle gap PHOto-neutralizer energy REcovery injector), based on the photo-detachment of negative ions and energy recovery of unneutralised ions; the main feature of SIPHORE being the relevance for the future Fusion reactors (DEMO), where high injector efficiency (up to 70-80%), technological simplicity and cost reduction are key issues to be addressed. The paper presents the on-going developments and simulations around this project, such as, a new concept of ion source which would fit with this injector topology and which could solve the remaining uniformity issue of the large size ion source, and, finally, the presentation of the R&D program in the laboratories (LAC, ARTEMIS) around the photo-neutralization for Siphore.

  14. Pulsed high current ion beam processing equipment

    International Nuclear Information System (INIS)

    Korenev, S.A.; Perry, A.

    1995-01-01

    A pulsed high voltage ion source is considered for use in ion beam processing for the surface modification of materials, and deposition of conducting films on different substrates. The source consists of an Arkad'ev-Marx high voltage generator, a vacuum ion diode based on explosive ion emission, and a vacuum chamber as substrate holder. The ion diode allows conducting films to be deposited from metal or allow sources, with ion beam mixing, onto substrates held at a pre-selected temperature. The main variables can be set in the ranges: voltage 100-700 kV, pulse length 0.3 μs, beam current 1-200 A depending on the ion chosen. The applications of this technology are discussed in semiconductor, superconductor and metallizing applications as well as the direction of future development and cost of these devices for commercial application. 14 refs., 6 figs

  15. HIGH ENERGY DENSITY PHYSICS EXPERIMENTS WITH INTENSE HEAVY ION BEAMS

    Energy Technology Data Exchange (ETDEWEB)

    Bieniosek, F.M.; Henestroza, E.; Leitner, M.; Logan, B.G.; More, R.M.; Roy, P.K.; Ni, P.; Seidl, P.A.; Waldron, W.L.; Barnard, J.J.

    2008-08-01

    The US heavy ion fusion science program has developed techniques for heating ion-beam-driven warm dense matter (WDM) targets. The WDM conditions are to be achieved by combined longitudinal and transverse space-charge neutralized drift compression of the ion beam to provide a hot spot on the target with a beam spot size of about 1 mm, and pulse length about 1-2 ns. As a technique for heating volumetric samples of matter to high energy density, intense beams of heavy ions are capable of delivering precise and uniform beam energy deposition dE/dx, in a relatively large sample size, and the ability to heat any solid-phase target material. Initial experiments use a 0.3 MeV K+ beam (below the Bragg peak) from the NDCX-I accelerator. Future plans include target experiments using the NDCX-II accelerator, which is designed to heat targets at the Bragg peak using a 3-6 MeV lithium ion beam. The range of the beams in solid matter targets is about 1 micron, which can be lengthened by using porous targets at reduced density. We have completed the fabrication of a new experimental target chamber facility for WDM experiments, and implemented initial target diagnostics to be used for the first target experiments in NDCX-1. The target chamber has been installed on the NDCX-I beamline. The target diagnostics include a fast multi-channel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. Initial WDM experiments will heat targets by compressed NDCX-I beams and will explore measurement of temperature and other target parameters. Experiments are planned in areas such as dense electronegative targets, porous target homogenization and two-phase equation of state.

  16. HIGH ENERGY DENSITY PHYSICS EXPERIMENTS WITH INTENSE HEAVY ION BEAMS

    Energy Technology Data Exchange (ETDEWEB)

    Henestroza, E.; Leitner, M.; Logan, B.G.; More, R.M.; Roy, P.K.; Ni, P.; Seidl, P.A.; Waldron, W.L.; Barnard, J.J.

    2010-03-16

    The US heavy ion fusion science program has developed techniques for heating ion-beam-driven warm dense matter (WDM) targets. The WDM conditions are to be achieved by combined longitudinal and transverse space-charge neutralized drift compression of the ion beam to provide a hot spot on the target with a beam spot size of about 1 mm, and pulse length about 1-2 ns. As a technique for heating volumetric samples of matter to high energy density, intense beams of heavy ions are capable of delivering precise and uniform beam energy deposition dE/dx, in a relatively large sample size, and the ability to heat any solid-phase target material. Initial experiments use a 0.3 MeV K+ beam (below the Bragg peak) from the NDCX-I accelerator. Future plans include target experiments using the NDCX-II accelerator, which is designed to heat targets at the Bragg peak using a 3-6 MeV lithium ion beam. The range of the beams in solid matter targets is about 1 micron, which can be lengthened by using porous targets at reduced density. We have completed the fabrication of a new experimental target chamber facility for WDM experiments, and implemented initial target diagnostics to be used for the first target experiments in NDCX-1. The target chamber has been installed on the NDCX-I beamline. The target diagnostics include a fast multi-channel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. Initial WDM experiments will heat targets by compressed NDCX-I beams and will explore measurement of temperature and other target parameters. Experiments are planned in areas such as dense electronegative targets, porous target homogenization and two-phase equation of state.

  17. HIGH ENERGY DENSITY PHYSICS EXPERIMENTS WITH INTENSE HEAVY ION BEAMS

    International Nuclear Information System (INIS)

    Bieniosek, F.M.; Henestroza, E.; Leitner, M.; Logan, B.G.; More, R.M.; Roy, P.K.; Ni, P.; Seidl, P.A.; Waldron, W.L.; Barnard, J.J.

    2008-01-01

    The US heavy ion fusion science program has developed techniques for heating ion-beam-driven warm dense matter (WDM) targets. The WDM conditions are to be achieved by combined longitudinal and transverse space-charge neutralized drift compression of the ion beam to provide a hot spot on the target with a beam spot size of about 1 mm, and pulse length about 1-2 ns. As a technique for heating volumetric samples of matter to high energy density, intense beams of heavy ions are capable of delivering precise and uniform beam energy deposition dE/dx, in a relatively large sample size, and the ability to heat any solid-phase target material. Initial experiments use a 0.3 MeV K+ beam (below the Bragg peak) from the NDCX-I accelerator. Future plans include target experiments using the NDCX-II accelerator, which is designed to heat targets at the Bragg peak using a 3-6 MeV lithium ion beam. The range of the beams in solid matter targets is about 1 micron, which can be lengthened by using porous targets at reduced density. We have completed the fabrication of a new experimental target chamber facility for WDM experiments, and implemented initial target diagnostics to be used for the first target experiments in NDCX-1. The target chamber has been installed on the NDCX-I beamline. The target diagnostics include a fast multi-channel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. Initial WDM experiments will heat targets by compressed NDCX-I beams and will explore measurement of temperature and other target parameters. Experiments are planned in areas such as dense electronegative targets, porous target homogenization and two-phase equation of state

  18. On Ion Drifts and Neutral Winds in Titan's Thermosphere

    Science.gov (United States)

    Shebanits, Oleg; Wahlund, Jan-Erik; Edberg, Niklas J. T.; Andrews, David J.; Crary, Frank J.; Wellbrock, Anne; Coates, Andrew; Mandt, Kathleen E.; Waite, J. Hunter, Jr.

    2015-04-01

    Saturn's largest moon Titan hosts an atmosphere with complex organic chemistry initiated in the ionosphere. The nightside chemistry may be influenced by the ion transport from the dayside ionosphere. In turn, ion transport (ion drifts) may be affected by the neutral winds, which cannot be measured directly by Cassini. In this study we derive the ion drifts along the spacecraft trajectories based on analysis of in-situ measurements of electron and ion fluxes, positive and negative ion masses and the magnetic field. Data from Titan flybys TA to T100 was included (Oct 2005 - Apr 2014), of which 55 flybys were below 1400 km and 48 below 1200 km altitude. From the electron and ion flux measurements three regions were observed: 1) above 1600 km, ions are ExB-drifting (frozen into the fields), 2) 1100-1600 km altitudes, dynamo-region, ions drift in opposite directions (perpendicular to B) and 3) 880-1100 km altitude (upper limit depends on convection electric field strength), ions are following neutrals and ion drifts translate to neutral winds of 0.5-2.5 km/s with weaker winds on the dayside of Titan's ionosphere.

  19. Resonant Effects in Neutral beam Moderation at TJ-II

    International Nuclear Information System (INIS)

    Guasp, J.; Liniers, M.; Fuentes, C.

    1999-01-01

    The structure of fast ion losses in neutral beam moderation at TJ-II is analysed theoretically, in particular the influence of resonant effects and the radial electric field dependence. The direct losses show strong resonant effects when the ratio of the poloidal and toroidal rotation velocities pass near the values -4/3, -2 or 0. These effects are visible as strong maxima on the loss fractions and also as characteristic trajectory behaviours. The delayed losses present resonant effects also, generally at intermediate energies (5 to 20 KeV for 40 keV injection). Near the resonances the population of passing particles in these losses is very high and the loss fraction can equal or even surpass the direct losses. In these delayed losses the particles concentrate along vertical strips on the loss cone diagrams of roughly constant parallel velocity. This parallel velocity increases with the electric field, the loss maxima are reached usually when the pitch and energy of these strips are near the initial injection values. The trapped particle population in these delayed losses is maximal at null electric and decreases with the field intensity for both potential signs. The corresponding final energies are usually low (1 to 5 keV). Except at extreme potentials, where the -4 resonance can appear, no resonant effects are observed for this population. The resonance ordering is similar for all configurations and follows reasonably the predictions of a simple model. The extreme configurations are dominated by the effects of the 0 and -2 resonances, giving very high loss fractions even for null electric field. In contrast the intermediate configurations, near the Reference one, do not present resonant effects and the losses are moderate at low potentials. Only above 2000 v the resonant effects start to appear. (Author) 11 refs

  20. Cobalt alloy ion sources for focused ion beam implantation

    Energy Technology Data Exchange (ETDEWEB)

    Muehle, R.; Doebeli, M. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Zimmermann, P. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-09-01

    Cobalt alloy ion sources have been developed for silicide formation by focused ion beam implantation. Four eutectic alloys AuCo, CoGe, CoY and AuCoGe were produced by electron beam welding. The AuCo liquid alloy ion source was investigated in detail. We have measured the emission current stability, the current-voltage characteristics, and the mass spectrum as a function of the mission current. (author) 1 fig., 2 refs.

  1. 3D-Printed Beam Splitter for Polar Neutral Molecules

    Science.gov (United States)

    Gordon, Sean D. S.; Osterwalder, Andreas

    2017-04-01

    We describe a macroscopic beam splitter for polar neutral molecules. A complex electrode structure is required for the beam splitter which would be very difficult to produce with traditional manufacturing methods. Instead, we make use of a nascent manufacturing technique: 3D printing of a plastic piece, followed by electroplating. This fabrication method opens a plethora of avenues for research, since 3D printing imposes practically no limitations on possible shapes, and the plating produces chemically robust, conductive construction elements with an almost free choice of surface material. It has the added advantage of dramatically reduced production cost and time. Our beam splitter is an electrostatic hexapole guide that smoothly transforms into two bent quadrupoles. We demonstrate the correct functioning of this device by separating a supersonic molecular beam of ND3 into two correlated fractions. It is shown that this device can be used to implement experiments with differential detection wherein one of the fractions serves as a probe and the other as a reference. Reverse operation would allow the merging of two beams of polar neutral molecules.

  2. Period doubling on a non-neutral magnetized electron beam

    International Nuclear Information System (INIS)

    Boswell, R.W.

    1984-01-01

    Low frequency oscillations on a non-neutral magnetized electron beam of very low density are investigated. A perturbation analysis of the slow mode of the rigid rotator equilibrium is developed to illustrate the nature of large amplitude fundamental mode oscillations. The results of this theoretical analysis show two important characteristics: firstly, as the perturbation amplitude is increasedthe waveform ceases to be purely sinusoidal and shows period doubling. Secondly, above a certain threshold, all harmonics of the wave grow and the wave breaks. The results of the former are compared with a simple electron beam experiment and are found to be in good qualitative agreement

  3. Tokamak heating by neutral beams and adiabatic compression

    International Nuclear Information System (INIS)

    Furth, H.P.

    1973-08-01

    ''Realistic'' models of tokamak energy confinement strongly favor reactor operation at the maximum MHD-stable β-value, in order to maximize plasma density. Ohmic heating is unsuitable for this purpose. Neutral-beam heating plus compression is well suited; however, very large requirements on device size and injection power seem likely for a DT ignition experiment using a Maxwellian plasma. Results of the ATC experiment are reviewed, including Ohmic heating, neutral-beam heating, and production of two-energy-component plasmas (energetic deuteron population in deuterium ''target plasma''). A modest extrapolation of present ATC parameters could give zero-power conditions in a DT experiment of the two-energy-component type. (U.S.)

  4. Ion beam processing of bio-ceramics

    Science.gov (United States)

    Ektessabi, A. M.

    1995-05-01

    Thin films of bio-inert (TiO 2+α, Al 2O 3+α) and bio-active (compounds of calcium and phosphorus oxides, hydroxyapatite) were deposited on the most commonly used implant materials such as titanium and stainless steel, using a dual-ion-beam deposition system. Rutherford backscattering spectroscopy was carried out for quantitative measurement of the interfacial atomic mixing and the composition of the elements. The experimental results show that by controlling the ion beam energy and current, thin films with very good mechanical properties are obtained as a result of the ion beam mixing within the film and at the interface of the film and substrate.

  5. Diagnostics Neutral Beam Injector at the TCV Tokamak

    International Nuclear Information System (INIS)

    Mlynar, J.; Shukaev, A.N.; Bosshard, P.; Duval, B.P.; Ivanov, A.A.; Kollegov, M.; Kolmogorov, V.V.; Llobet, X.; Pitts, R.A.; Weisen, H.

    2001-10-01

    Within this report we summarize the technical and experimental effort made on diagnostics neutral beam injector (DNBI) which was installed at tokamak TCV last year. Basic components of DNBI are reviewed, its remote control is presented in more detail. Profile and attenuation studies are referred to. First experimental results obtained with DNBI, which led to a decision to upgrade the machine, are discussed in the last section. (author)

  6. Heavy Neutral Beam Probe for Edge Plasma Analysis in Tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Castracane, J.

    2001-01-04

    The Heavy Neutral Beam Probe (HNBP) developed initially with DOE funding under the Small Business Innovation Research (SBIR) program was installed on the Tokamak de Varennes (TdeV) at the CCFM. This diagnostic was designed to perform fundamental measurements of edge plasma properties. The hardware was capable of measuring electron density and potential profiles with high spatial and temporal resolution. Fluctuation spectra for these parameters were obtained with HNBP for transport studies.

  7. Heavy Neutral Beam Probe for Edge Plasma Analysis in Tokamaks

    International Nuclear Information System (INIS)

    Castracane, J.

    2001-01-01

    The Heavy Neutral Beam Probe (HNBP) developed initially with DOE funding under the Small Business Innovation Research (SBIR) program was installed on the Tokamak de Varennes (TdeV) at the CCFM. This diagnostic was designed to perform fundamental measurements of edge plasma properties. The hardware was capable of measuring electron density and potential profiles with high spatial and temporal resolution. Fluctuation spectra for these parameters were obtained with HNBP for transport studies

  8. Comparison of laser and neutral particle beam discrimination

    Energy Technology Data Exchange (ETDEWEB)

    Canavan, G.H.

    1989-09-01

    The relative ability of lasers and neutral particle beams (NPBs) to discriminate reentry vehicle (RV) and anti-satellite (ASAT) decoys is pivotal in assessing their relative worth as strategic defenses. This report evaluates their ability and assesses their relative contributions, concluding that NPBs can typically discriminate about 100 times as many objects as can lasers, and do so with significantly greater certainty. 7 refs., 2 figs.

  9. Conceptual design for the ZEPHYR neutral-beam injection system

    International Nuclear Information System (INIS)

    Cooper, W.S.; Elischer, V.P.; Goldberg, D.A.; Hopkins, D.B.; Jacobson, V.L.; Lou, K.H.; Tanabe, J.T.

    1981-03-01

    In June 1980, the Lawrence Berkeley Laboratory began a conceptual design study for a neutral beam injection system for the ZEPHYR ignition tokamak proposed by the Max-Planck-Institut fur Plasmaphysik in Garching, Germany. The ZEPHYR project was cancelled, and the LBL design effort concluded prematurely in January 1981. This report describes the conceptual design as it existed at that time, and gives brief consideration to a schedule, but does not deal with costs

  10. Neutral beam control systems for the Tandem Mirror Experiment

    International Nuclear Information System (INIS)

    Ross, R.I.

    1979-01-01

    The Tandem Mirror Experiment (TMX) is presently developing the technology and approaches which will be used in larger fusion systems. This paper describes some of the designs which were used in creating the control system for the TMX neutral beams. To create a system of controls that would work near these large, rapid switching current sources required a mixture of different technologies: fiberoptic data transmission, printed circuit and wirewrap techniques, etc

  11. Conceptual design for the ZEPHYR neutral-beam injection system

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, W.S.; Elischer, V.P.; Goldberg, D.A.; Hopkins, D.B.; Jacobson, V.L.; Lou, K.H.; Tanabe, J.T.

    1981-03-01

    In June 1980, the Lawrence Berkeley Laboratory began a conceptual design study for a neutral beam injection system for the ZEPHYR ignition tokamak proposed by the Max-Planck-Institut fur Plasmaphysik in Garching, Germany. The ZEPHYR project was cancelled, and the LBL design effort concluded prematurely in January 1981. This report describes the conceptual design as it existed at that time, and gives brief consideration to a schedule, but does not deal with costs.

  12. Diagnostic studies of ion beam formation in inductively coupled plasma

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, Jenee L. [Iowa State Univ., Ames, IA (United States)

    2015-01-01

    This dissertation describes a variety of studies focused on the plasma and the ion beam in inductively coupled plasma mass spectrometry (ICP-MS). The ability to use ICP-MS for measurements of trace elements in samples requires the analytes to be efficiently ionized. Updated ionization efficiency tables are discussed for ionization temperatures of 6500 K and 7000 K with an electron density of 1 x 1015 cm-3. These values are reflective of the current operating parameters of ICP-MS instruments. Calculations are also discussed for doubly charged (M2+) ion formation, neutral metal oxide (MO) ionization, and metal oxide (MO+) ion dissociation for similar plasma temperature values. Ionization efficiency results for neutral MO molecules in the ICP have not been reported previously.

  13. Laser-induced positive ion and neutral atom/molecule emissions from single-crystal CaHPO4 center dot 2H20: The role of electron-beam-induced defects

    International Nuclear Information System (INIS)

    Dawes, Mary L.; Hess, Wayne P.; Kawaguchi, Yuji; Langford, S C.; Dickinson, J. Tom

    1998-01-01

    We examine laser-induced ion and neutral emissions from single-crystal CaHPO4 center dot 2H2O (brushite), a wide-band-gap, hydrated inorganic single crystal, with 248-nm excimer laser radiation. Both laser-induced ion and neutral emissions are several orders magnitude higher following exposure to 2keV electrons at current densities of 200 uA/cm2 and doses of 1 C/cm2. In addition to intense Ca+ signals, electron-irradiated surfaces yield substantial CaO+, PO+, and P+ signals. As-grown and as-cleaved brushite show only weak neutral O2 and Ca emissions, whereas electron-irradiated surfaces yield enhanced O2, Ca, PO, PO2, and P emissions. Electron irradiation (i) significantly heats the sample, leading to thermal dehydration (CaHPO4 formation) and pyrolysis (Ca2P2O7 formation)and (ii) chemically reduces the surface via electron stimulated desorption. The thermal effects are accompanied by morphological changes, including recrystallization. Although complex, these changes lead to high defect densities, which are responsible for the dramatic enhancements in the observed laser desorption

  14. Programmable controller--a versatile tool for neutral beam control

    International Nuclear Information System (INIS)

    Campbell, G.L.; Haskovec, J.S.; Moore, C.D.

    1983-01-01

    In neutral beam systems (NB) for the Doublet III fusion experiment at GA Technologies Inc., programmable controllers (PC) are successfully used both on the local and the central levels of control. The local level of control is concentrated in the control instrumentation station (CI), located near the neutral beam tank and its instrumentation. The CI station contains one PC which performs control functions for vacuum, hydrogen, cooling water, automatic cryopanel defrost and recovery from power failure. The CI PC provides interface functions to other local control devices as well as to the NB control computer and central level of control. On the central level the PC creates the main part of a mode control system (MC). It supports mode control panels which serve as global control interface to NB operator, coordinates the operation of NB power supplies, central timing system, neutral beam and tokamak control computers. After a brief exposition of typical functions the implication of requirements such as expandability, reliability and versatility on hardware configuration and program structure will be explained. Results of analysis and tests of time-critical functions will be presented. Finally some aspects of interfaces to different instruments and devices will be described

  15. Plasma ion sources and ion beam technology inmicrofabrications

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Lili [Univ. of California, Berkeley, CA (United States)

    2007-01-01

    For over decades, focused ion beam (FIB) has been playing a very important role in microscale technology and research, among which, semiconductor microfabrication is one of its biggest application area. As the dimensions of IC devices are scaled down, it has shown the need for new ion beam tools and new approaches to the fabrication of small-scale devices. In the meanwhile, nanotechnology has also deeply involved in material science research and bioresearch in recent years. The conventional FIB systems which utilize liquid gallium ion sources to achieve nanometer scale resolution can no longer meet the various requirements raised from such a wide application area such as low contamination, high throughput and so on. The drive towards controlling materials properties at nanometer length scales relies on the availability of efficient tools. In this thesis, three novel ion beam tools have been developed and investigated as the alternatives for the conventional FIB systems in some particular applications. An integrated focused ion beam (FIB) and scanning electron microscope (SEM) system has been developed for direct doping or surface modification. This new instrument employs a mini-RF driven plasma source to generate focused ion beam with various ion species, a FEI two-lens electron (2LE) column for SEM imaging, and a five-axis manipulator system for sample positioning. An all-electrostatic two-lens column has been designed to focus the ion beam extracted from the source. Based on the Munro ion optics simulation, beam spot sizes as small as 100 nm can be achieved at beam energies between 5 to 35 keV if a 5 μm-diameter extraction aperture is used. Smaller beam spot sizes can be obtained with smaller apertures at sacrifice of some beam current. The FEI 2LE column, which utilizes Schottky emission, electrostatic focusing optics, and stacked-disk column construction, can provide high-resolution (as small as 20 nm) imaging capability, with fairly long working distance (25

  16. Plasma ion sources and ion beam technology in microfabrications

    International Nuclear Information System (INIS)

    Ji, Lili

    2007-01-01

    For over decades, focused ion beam (FIB) has been playing a very important role in microscale technology and research, among which, semiconductor microfabrication is one of its biggest application area. As the dimensions of IC devices are scaled down, it has shown the need for new ion beam tools and new approaches to the fabrication of small-scale devices. In the meanwhile, nanotechnology has also deeply involved in material science research and bioresearch in recent years. The conventional FIB systems which utilize liquid gallium ion sources to achieve nanometer scale resolution can no longer meet the various requirements raised from such a wide application area such as low contamination, high throughput and so on. The drive towards controlling materials properties at nanometer length scales relies on the availability of efficient tools. In this thesis, three novel ion beam tools have been developed and investigated as the alternatives for the conventional FIB systems in some particular applications. An integrated focused ion beam (FIB) and scanning electron microscope (SEM) system has been developed for direct doping or surface modification. This new instrument employs a mini-RF driven plasma source to generate focused ion beam with various ion species, a FEI two-lens electron (2LE) column for SEM imaging, and a five-axis manipulator system for sample positioning. An all-electrostatic two-lens column has been designed to focus the ion beam extracted from the source. Based on the Munro ion optics simulation, beam spot sizes as small as 100 nm can be achieved at beam energies between 5 to 35 keV if a 5 (micro)m-diameter extraction aperture is used. Smaller beam spot sizes can be obtained with smaller apertures at sacrifice of some beam current. The FEI 2LE column, which utilizes Schottky emission, electrostatic focusing optics, and stacked-disk column construction, can provide high-resolution (as small as 20 nm) imaging capability, with fairly long working distance

  17. Consideration of beam plasma ion-source

    International Nuclear Information System (INIS)

    Sano, Fumimichi; Kusano, Norimasa; Ishida, Yoshihiro; Ishikawa, Junzo; Takagi, Toshinori

    1976-01-01

    Theoretical and experimental analyses and their comparison were made on the plasma generation and on the beam extraction for the beam plasma ion-source. The operational principle and the structure of the ion-source are explained in the first part. Considerations are given on the electron beam-plasma interaction and the resulting generation of high frequency or microwaves which in turn increases the plasma density. The flow of energy in this system is also explained in the second part. The relation between plasma density and the imaginary part of frequency is given by taking the magnetic flux density, the electron beam energy, and the electron beam current as parameters. The relations between the potential difference between collector and drift tube and the plasma density or the ion-current are also given. Considerations are also given to the change of the plasma density due to the change of the magnetic flux density at drift tube, the change of the electron beam energy, and the change of the electron beam current. The third part deals with the extraction characteristics of the ion beam. The structure of the multiple-aperture electrode and the relation between plasma density and the extracted ion current are explained. (Aoki, K.)

  18. Heavy ion beams from the new Hungarian ECR ion source

    International Nuclear Information System (INIS)

    Biri, S.; Valek, A.; Ditroi, F.; Koivisto, H.; Arje, J.; Stiebing, K.; Schmidt, L.

    1998-01-01

    The first beams of highly charged ions in Hungary were obtained in fall of 1996. The new 14.5 GHz ECR ion source of ATOMKI produced beams of multiply charged ions with remarkable intensities at first experiments. Since then, numerous further developments were carried out. An external electrondonor electrode drastically increased the plasma density and, consequently, the intensity of highly charged ions. These upgrades concentrated mainly on beams from gaseous elements and were carried out by the ECRIS team of ATOMKI. Another series of experiments - ionising from solids - however, was done in the framework of an international collaboration. The first metal ion beam has been extracted from the ECRIS in November 1997 using the known method of Metal Ions from Volatile Compounds (MIVOC). The possibility to put the MIVOC chamber inside the ion source was also tested and the dosing regulation problem of metal vapours inside the ion source was solved. As a result, beams of more than 10 μA of highly charged Fe and Ni ions were produced. (author)

  19. Development of neutral beam injectors for JET at FAR

    International Nuclear Information System (INIS)

    Bariaud, A.; Becherer, R.; Desmons, M.; Fumelli, M.; Raimbault, R.; Valckx, F.P.G.

    1980-09-01

    A rectangular version of the periplasmatron ion source capable of illuminating with a homogeneous plasma of 40 x 18 cm 2 extraction area has been constructed at FAR for the need of JET. Intense ion beams up to 40 A, 80 keV energy, 240 mA/cm 2 extracted ion current density, 0,1 sec pulse length have been produced with this source by using an extraction area of 12 x 38 cm 2 and a three electrodes multi-aperture extraction system. The full size JET ion source will be an extrapolated version with an extraction area of 18 x 45 cm 2 . The line is now in operation with an electrostatic beam dump, which is under test. Experiments have been carried out, to investigate some phenomena which affects the injector operation like the thermal load of the grids by the acceleration of charged particles created in the accelerating gaps of the beam-forming electrodes and the transmission losses due to the beam divergence

  20. Potential biomedical applications of ion beam technology

    Science.gov (United States)

    Banks, B. A.; Weigand, A. J.; Van Kampen, C. L.; Babbush, C. A.

    1976-01-01

    Electron bombardment ion thrusters used as ion sources have demonstrated a unique capability to vary the surface morphology of surgical implant materials. The microscopically rough surface texture produced by ion beam sputtering of these materials may result in improvements in the biological response and/or performance of implanted devices. Control of surface roughness may result in improved attachment of the implant to soft tissue, hard tissue, bone cement, or components deposited from blood. Potential biomedical applications of ion beam texturing discussed include: vascular prostheses, artificial heart pump diaphragms, pacemaker fixation, percutaneous connectors, orthopedic prosthesis fixation, and dental implants.

  1. Multiple track Doppler-shift spectroscopy system for TFTR neutral beam injectors

    International Nuclear Information System (INIS)

    Kamperschroer, J.H.; Kugel, H.W.; Reale, M.A.

    1986-09-01

    A Doppler-shift spectroscopy system has been installed on the TFTR neutral beam injection system to measure species composition during both conditioning and injection pulses. Two intensified vidicon detectors and two spectrometers are utilized in a system capable of resolving data from up to twelve ion sources simultaneously. By imaging the light from six ion sources onto one detector, a cost-effective system has been achieved. Fiber optics are used to locate the diagnostic in an area remote from the hazards of the tokamak test cell allowing continuous access, and eliminating the need for radiation shielding of electronic components. Automatic hardware arming and interactive data analysis allow beam composition to be computed between tokamak shots for use in analyzing plasma heating experiments. Measurements have been made using lines of sight into both the neutralizer and the drift duct. Analysis of the data from the drift duct is both simpler and more accurate since only neutral particles are present in the beam at this location. Comparison of the data taken at these two locations reveals the presence of partially accelerated particles possessing an estimated 1/e half-angle divergence of 15 0 and accounting for up to 30% of the extracted power

  2. Primary beams of an electron beam ion source (EBIS)

    International Nuclear Information System (INIS)

    Lenoir-Zink, E.

    1986-06-01

    Electron guns for the ion sources of the SATURN II facility were tested and compared with models. The guns tested were a gun with 36 mm diameter cathode, 7 mm, 4 mm, 4 mm with insulated Whenelt, and 8 mm. A lanthanium hexaboride cathode is presented. For the primary ion beams, zeolite and plasma sources were realized. In DIONE, which will replace CRYEBIS as ion source in SATURNE, the density of the electron beam compressed within the maximum magnetic field can be evaluated. Results indicate a factor of 3 improvement compared with CRYEBIS. Lithium sources can be used, but gas sources do not produce significant improvements [fr

  3. Applications of focused ion beams in microelectronics

    International Nuclear Information System (INIS)

    Broughton, C.; Beale, M.I.J.; Deshmukh, V.G.I.

    1986-04-01

    We present the conclusions of the RSRE programme on the application of focused ion beams in microelectronics and review the literature published in this field. We discuss the design and performance of focused beam implanters and the viability of their application to semiconductor device fabrication. Applications in the areas of lithography, direct implantation and micromachining are discussed in detail. Comparisons are made between the use of focused ion beams and existing techniques for these fabrication processes with a strong emphasis placed on the relative throughputs. We present results on a novel spot size measurement technique and the effect of beam heating on resist. We also present the results of studies into implantation passivation of resist to oxygen plasma attack as basis for a dry development lithography scheme. A novel lithography system employing flood electron exposure from a photocathode which is patterned by a focused ion beam which can also be used to repair mask defects is considered. (author)

  4. Subthreshold Production of Neutral Pions in Heavy Ion Collisions

    CERN Multimedia

    2002-01-01

    The pion production below the threshold at 290 MeV/u (corresponding to the minimum beam velocity at which pions can be produced in nucleon-nucleon collisions) is sensitive to coherent effects in the momentum distribution of the nucleons in the internuclear collision region. Such collective or coherent effects would manifest themselves in an enhancement of the observed cross section with respect to a prediction on the basis of model momentum distributions, e.g. from the Fermi gas model. \\\\ \\\\ With neutral pions such experiments can be extended to rather low energies and rather small cross sections (in the sub-@mb range) due to the fact that the @p|0's leave the composite nuclear system undisturbed by the Coulomb forces and that their decay $\\gamma$ rays can be detected with high efficiency also at very low pion momentum. In our experiments using |1|2C~ions of 60, 74 and 84~MeV/u and |1|80 of 84~MeV/u we were able to clearly sep from background from different sources. The large efficiency of the annular lead gl...

  5. Intense pulsed ion beams for fusion applications

    International Nuclear Information System (INIS)

    Humphries, S. Jr.

    1980-04-01

    The subject of this review paper is the field of intense pulsed ion beam generation and the potential application of the beams to fusion research. Considerable progress has been made over the past six years. The ion injectors discussed utilize the introduction of electrons into vacuum acceleration gaps in conjunction with high voltage pulsed power technology to achieve high output current. Power levels from injectors exceeding 1000 MW/cm 2 have been obtained for pulse lengths on the order of 10 -7 sec. The first part of the paper treats the physics and technology of intense ion beams. The second part is devoted to applications of intense ion beams in fusion research. A number of potential uses in magnetic confinement systems have been proposed

  6. Accelerated ion beam research at ATOMKI

    International Nuclear Information System (INIS)

    Kiss, A.Z.

    2009-01-01

    The paper summarizes the studies on accelerated ion beams at ATOMKI and their technical background, their use from chemical analysis to biological, medical, geological, archaeological applications, their advance from material science to micromachining. (TRA)

  7. Uses of laser optical pumping to produce polarized ion beams

    International Nuclear Information System (INIS)

    Anderson, L.W.

    1983-01-01

    Laser optical pumping can be used to produce polarized alkali atom beams or polarized alkali vapor targets. Polarized alkali atom beams can be converted into polarized alkali ion beams, and polarized alkali vapor targets can be used to produce polarized H - or 3 He - ion beams. In this paper the authors discuss how the polarized alkali atom beams and polarized alkali vapor targets are used to produce polarized ion beams with emphasis on the production of polarized negative ion beams

  8. The text neutral lithium beam edge density diagnostic

    International Nuclear Information System (INIS)

    Howald, A.M.; McChesney, J.M.; West, W.P.

    1994-07-01

    A fast neutral lithium beam has been installed on the TEXT tokamak for Beam Emission Spectroscopy (BES) studies of the edge plasma electron density profile. The diagnostic was recently upgraded from ten to twenty spatial channels, each of which has two detectors, one to measure lithium beam signal and one to monitor plasma background light. The spatial resolution is 6 mm, and the temporal resolution is designed to be as high as 10 ms for studies of transient events including plasma density fluctuations. Initial results are presented from the ten-channel system: Edge electron densities unfolded from the LiI(2 s 2 S - 2 p 2 P) 670.8 nm emission profile have the same general time dependence as the line-averaged density measured by microwave interferometry

  9. Welding for fusion grade neutral beam components - requirements, challenges, experiences and learnings

    International Nuclear Information System (INIS)

    Joshi, Jaydeep; Patel, Hitesh; Yadav, Ashish; Rotti, Chandramouli; Bandyopadhyay, Mainak; Chakraborty, Arun

    2016-01-01

    Negative ion based Neutral Beam Injectors (NBI) are the integral part of large size fusion devices where Neutral Beams of Hydrogen/Deuterium atoms are injected into the fusion reactor to heat the plasma, drive a plasma current, provide fuel to the plasma and also help to diagnose the plasma through spectroscopic measurements. The presentation shares the experiences of handling, some of special welding activities applicable for fusion prototypes developments, experiments, methodology developed for the inspection/tests, criteria considered with the appropriate justifications. This also shares the view point of authors code should further be supplement and incorporate the fusion specific applications considering future needs. In addition, explorations to meet our future needs of welding with specific attention to indigenous developments have been described

  10. A rule-based computer control system for PBX-M neutral beams

    International Nuclear Information System (INIS)

    Frank, K.T.; Kozub, T.A.; Kugel, H.W.

    1987-01-01

    The Princeton Beta Experiment (PBX) neutral beams have been routinely operated under automatic computer control. A major upgrade of the computer configuration was undertaken to coincide with the PBX machine modification. The primary tasks included in the computer control system are data acquisition, waveform reduction, automatic control and data storage. The portion of the system which will remain intact is the rule-based approach to automatic control. Increased computational and storage capability will allow the expansion of the knowledge base previously used. The hardware configuration supported by the PBX Neutral Beam (XNB) software includes a dedicated Microvax with five CAMAC crates and four process controllers. The control algorithms are rule-based and goal-driven. The automatic control system raises ion source electrical parameters to selected energy goals and maintains these levels until new goals are requested or faults are detected

  11. Ion beam processing of advanced electronic materials

    International Nuclear Information System (INIS)

    Cheung, N.W.; Marwick, A.D.; Roberto, J.B.

    1989-01-01

    This report contains research programs discussed at the materials research society symposia on ion beam processing of advanced electronic materials. Major topics include: shallow implantation and solid-phase epitaxy; damage effects; focused ion beams; MeV implantation; high-dose implantation; implantation in III-V materials and multilayers; and implantation in electronic materials. Individual projects are processed separately for the data bases

  12. Ion beam processing of advanced electronic materials

    Energy Technology Data Exchange (ETDEWEB)

    Cheung, N.W.; Marwick, A.D.; Roberto, J.B. (eds.) (California Univ., Berkeley, CA (USA); International Business Machines Corp., Yorktown Heights, NY (USA). Thomas J. Watson Research Center; Oak Ridge National Lab., TN (USA))

    1989-01-01

    This report contains research programs discussed at the materials research society symposia on ion beam processing of advanced electronic materials. Major topics include: shallow implantation and solid-phase epitaxy; damage effects; focused ion beams; MeV implantation; high-dose implantation; implantation in III-V materials and multilayers; and implantation in electronic materials. Individual projects are processed separately for the data bases. (CBS)

  13. TXRF spectrometry at ion beam excitation

    Science.gov (United States)

    Egorov, V.; Egorov, E.; Afanas'ef, M.

    2017-02-01

    The work presents short discussion of TXRF and PIXE methods peculiarities. Taking into account of these peculiarities we elaborate the experimental scheme for TXRF measurements at ion beam excitation of characteristical fluorescence. The scheme is built on base of the planar X-ray waveguide-resonator with specific design. Features of the new experimental method and possibilities of Sokol-3 ion beam analytical complex were used for the method application in real measurements.

  14. Space-charge-limited ion flow through an ionizing neutral layer

    International Nuclear Information System (INIS)

    Duvall, R.E.; Litwin, C.; Maron, Y.

    1993-01-01

    Space-charge-limited ion flow through an ionizing layer of neutral atoms is studied. The ion flow is between two parallel conducting plates (anode and cathode) with an externally applied voltage between them. An expanding layer of neutral atoms is adjacent to the anode surface, extending a finite distance into the anode--cathode gap. All ions originate either from the anode surface or from the ionization of neutrals; electrons originate only from ionization. Electrons are strongly magnetized by an externally applied, time-independent direct current (dc) magnetic field directed across the ion flow. The ions are unmagnetized, all motion being perpendicular to the conducting plates. Two different models of the anode layer were used to analyze this problem: a multifluid steady-state model and a single fluid time-dependent model. From both models it was found that the anode surface becomes shielded after the ion flux from the ionizing layer becomes larger than the space-charge-limited flux of the reduced gap between the neutral layer and cathode. Comparison was made between the time-dependent model and results from magnetically insulated ion beam diode (MID) experiments. Using an initial areal density of neutral hydrogen and carbon equal to the final observed electron areal density, comparison was made between calculated plasma shielding times and upper bounds on the shielding time observed in experiments. It was found that a layer of neutral hydrogen must contain a minimum of 15% carbon (by number density) to explain the rapid electric field screening observed in experiments

  15. Particle and momentum confinement in tokamak plasmas with unbalanced neutral beam injection and strong rotation

    International Nuclear Information System (INIS)

    Malik, M.A.

    1988-01-01

    There is a self-consistent theory of the effects of neutral beam injection on impurity transport in tokamak plasmas. The theory predicts that co-injection drives impurities outward and that counter-injection enhances the normally inward flow of impurities. The theory was applied to carry out a detailed analysis of the large experimental database from the PLT and the ISX-B tokamaks. The theory was found to generally model the experimental data quite well. It is, therefore, concluded that neutral beam co-injection can drive impurities outward to achieve clean central plasmas and a cool radiating edge. Theoretical predictions for future thermonuclear reactors such as INTOR, TIBER II, and ITER indicated that neutral beam driven flow reversal might be an effective impurity control method if the rate of beam momentum deposited per plasma ion is adequate. The external momentum drag, which is a pivotal concept in impurity flow reversal theory, is correctly predicted by the gyroviscous theory of momentum confinement. The theory was applied to analyze experimental data from the PLT and the PDX tokamaks with exact experimental conditions. The theory was found to be in excellent agreement with experiment over a wide range of parameters. It is, therefore, possible to formulate the impurity transport theory from first principles, without resort to empiricism

  16. 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

  17. National Centre for Radioactive Ion Beams (NCRIB)

    International Nuclear Information System (INIS)

    Chintalapudi, S.N.

    1999-01-01

    A dedicated National Centre for RIB (NCRIB) proposed discussed at several forums is presented. The production of (RIB) radioactive ion beams and applications of beams leading to competitive studies in nuclear structure, nuclear reactions, condensed matter, bio-science and radioactive isotope production etc. are mentioned

  18. Computational studies of the effect of magnetic field ''ripple'' on neutral beam heating of ZEPHYR

    International Nuclear Information System (INIS)

    Lister, G.G.; Gruber, O.

    1981-01-01

    The results of computations to estimate the heating efficiency of neutral injection in the proposed ZEPHYR experiment are presented. A suitably modified version of the Monte-Carlo neutral deposition and orbit following code FREYA was used for these calculations, in which particular emphasis has been placed on the effects of toroidal field ripple. We find that the ripple associated with the preliminary design of the experiment (+-6%) would result in intolerable energy losses due to ''ripple trapping'' of the fast ions produced by the neutral beam and insufficient heating of the central plasma. The necessary conditions for ignition can be obtained with a total heating power of 25 MW provided the ripple can be reduced to +-1%, in which case energy losses could be kept below 30%. These results are compatible with those found from transport code calculations of the losses to be expected due to ripple enhanced thermal conduction in the plasma

  19. Pinched Ion Beam Transport in the Target Chamber

    Science.gov (United States)

    Rosenbluth, M.; Lee, E. P.; Briggs, R. J.

    2000-10-01

    Ion beam pulses for fusion reactors have a very high charge per unit length and may carry a high current. In order to avoid thermal blowup and focus to a small spot, it is required to be charge neutral and desirable to have a pinching magnetic field. This requires that the neutralizing electrons flow relative to the ions, and of course the pinch behavior depends on the return current path. Since the electrons have small gyroradii a fluid, charge neutral model is adopted. After the pulse has been well detached from the chamber entrance hole and is distant from all emitting surfaces fields, we look for a steady-state solution in the beam frame with electrons recirculating. We find the conditions for such "plasmoid" solutions, indicating the desirability of shaping the radial profile and find that while the outer part of the beam pulse is blown out, the core may be reasonably well pinch-confined. The effects of interactions with background gas and plasma are discussed. We plan to study possible instabilities-kink, sausage, Rayleigh-Taylor and filamentation.

  20. A pencil beam algorithm for helium ion beam therapy.

    Science.gov (United States)

    Fuchs, Hermann; Strobele, Julia; Schreiner, Thomas; Hirtl, Albert; Georg, Dietmar

    2012-11-01

    To develop a flexible pencil beam algorithm for helium ion beam therapy. Dose distributions were calculated using the newly developed pencil beam algorithm and validated using Monte Carlo (MC) methods. The algorithm was based on the established theory of fluence weighted elemental pencil beam (PB) kernels. Using a new real-time splitting approach, a minimization routine selects the optimal shape for each sub-beam. Dose depositions along the beam path were determined using a look-up table (LUT). Data for LUT generation were derived from MC simulations in water using GATE 6.1. For materials other than water, dose depositions were calculated by the algorithm using water-equivalent depth scaling. Lateral beam spreading caused by multiple scattering has been accounted for by implementing a non-local scattering formula developed by Gottschalk. A new nuclear correction was modelled using a Voigt function and implemented by a LUT approach. Validation simulations have been performed using a phantom filled with homogeneous materials or heterogeneous slabs of up to 3 cm. The beams were incident perpendicular to the phantoms surface with initial particle energies ranging from 50 to 250 MeV/A with a total number of 10(7) ions per beam. For comparison a special evaluation software was developed calculating the gamma indices for dose distributions. In homogeneous phantoms, maximum range deviations between PB and MC of less than 1.1% and differences in the width of the distal energy fall off of the Bragg-Peak from 80% to 20% of less than 0.1 mm were found. Heterogeneous phantoms using layered slabs satisfied a γ-index criterion of 2%/2mm of the local value except for some single voxels. For more complex phantoms using laterally arranged bone-air slabs, the γ-index criterion was exceeded in some areas giving a maximum γ-index of 1.75 and 4.9% of the voxels showed γ-index values larger than one. The calculation precision of the presented algorithm was considered to be sufficient

  1. A synchronous beam sweeper for heavy ions

    International Nuclear Information System (INIS)

    Bogaty, J.M.

    1989-01-01

    The Argonne Tandem Linac Accelerator System (ATLAS) facility at Argonne National Laboratory provides a wide range of accelerated heavy ions from the periodic table. Frequently, the beam delivery rate of 12 MHz is too fast for the type of experiment on line. Reaction by-products from a target bombardment may have a decay interval much longer than the dead time between beam bunches. To prevent data from being corrupted by incoming ions a beam sweeper was developed which synchronously eliminates selected beam bunches to suit experimental needs. As the SWEEPER is broad band (DC to 6 MHz) beam delivery rates can be instantaneously changed. Ion beam bunches are selectively kicked out by an electrostatic dipole electrode pulsed to 2 kVDC. The system has been used for almost three years with several hundred hours of operating time logged to date. Beam bunch delivery rates of 6 MHz down to 25 kHz have been provided. Since this is a non-resonant system any beam delivery rate from 6 MHz down to zero can be set. In addition, burst modes have been used where beam is supplied in 12 MHz bursts and then shut down for a period of time set by the user. 3 figs

  2. 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

  3. Aberration of a negative ion beam caused by space charge effect.

    Science.gov (United States)

    Miyamoto, K; Wada, S; Hatayama, A

    2010-02-01

    Aberrations are inevitable when the charged particle beams are extracted, accelerated, transmitted, and focused with electrostatic and magnetic fields. In this study, we investigate the aberration of a negative ion accelerator for a neutral beam injector theoretically, especially the spherical aberration caused by the negative ion beam expansion due to the space charge effect. The negative ion current density profiles with the spherical aberration are compared with those without the spherical aberration. It is found that the negative ion current density profiles in a log scale are tailed due to the spherical aberration.

  4. Beam current controller for laser ion source

    Science.gov (United States)

    Okamura, Masahiro

    2014-10-28

    The present invention relates to the design and use of an ion source with a rapid beam current controller for experimental and medicinal purposes. More particularly, the present invention relates to the design and use of a laser ion source with a magnetic field applied to confine a plasma flux caused by laser ablation.

  5. A stable production of intense electron beam plasma with ion back stream

    International Nuclear Information System (INIS)

    Uramoto, Johshin.

    1975-12-01

    An intense electron beam is extracted without space charge limit from a dc plasma source along a magnetic field. The beam space charge is neutralized stably through back streaming of self-ionized ions from the beam extracting anode region where a neutral gas is fed locally. In Appendix I, a space charge free electron gun is designed under this neutralization method. In Appendix II, a dynamic discharge through a series resistance is described, where an operative mechanism of the well-known TP-D plasma is clarified. (auth.)

  6. Experimental studies with radioactive ion beams

    International Nuclear Information System (INIS)

    Sastry, D.L.; Sree Krishna Murty, G.; Chandrasekhar Rao, M.V.S.

    1991-01-01

    The sources of information presented are essentially taken from the papers reported at several international seminars and those appeared in the Journal of Nuclear Instruments and Methods in Physics Research. Production and usage of radioactive ion beams (RIB) in research have received the attention of scientists all over the world during the past six years. The first radioactive ion beams ( 19 Ne) were produced at Bevalac for the purpose of medical research using a primary beam of energy 800 MeV/a.m.u. (author). 19 refs., 2 figs., 3 tabs

  7. BEAM TRANSPORT AND STORAGE WITH COLD NEUTRAL ATOMS AND MOLECULES

    Energy Technology Data Exchange (ETDEWEB)

    Walstrom, Peter L. [Los Alamos National Laboratory

    2012-05-15

    A large class of cold neutral atoms and molecules is subject to magnetic field-gradient forces. In the presence of a field, hyperfine atomic states are split into several Zeeman levels. The slopes of these curves vs. field are the effective magnetic moments. By means of optical pumping in a field, Zeeman states of neutral lithium atoms and CaH molecules with effective magnetic moments of nearly {+-} one Bohr magneton can be selected. Particles in Zeeman states for which the energy increases with field are repelled by increasing fields; particles in states for which the energy decreases with field are attracted to increasing fields. For stable magnetic confinement, field-repelled states are required. Neutral-particle velocities in the present study are on the order of tens to hundreds of m/s and the magnetic fields needed for transport and injection are on the order of in the range of 0.01-1T. Many of the general concepts of charged-particle beam transport carry over into neutral particle spin-force optics, but with important differences. In general, the role of bending dipoles in charged particle optics is played by quadrupoles in neutral particle optics; the role of quadrupoles is played by sextupoles. The neutralparticle analog of charge-exchange injection into storage rings is the use of lasers to flip the state of particles from field-seeking to field-repelled. Preliminary tracking results for two neutral atom/molecule storage ring configurations are presented. It was found that orbit instabilities limit the confinment time in a racetrack-shaped ring with discrete magnetic elements with drift spaces between them; stable behavior was observed in a toroidal ring with a continuous sextupole field. An alternative concept using a linear sextupole or octupole channel with solenoids on the ends is presently being considered.

  8. Ion beam source construction and applications

    International Nuclear Information System (INIS)

    Torab, S.I.R.

    2011-01-01

    The aim of this thesis is to improve the performance of a new shape cold cathode Penning ion source to be suitable for some applications. In this work, many trials have been made to reach the optimum dimensions of the new shape of cold Molybdenum cathode Penning ion source with radial extraction. The high output ion beam can be extracted in a direction transverse to the discharge region. The new shape cold cathode Penning ion source consists of Copper cylindrical hollow anode of 40 mm length, 12 mm diameter and has two similar cone ends of 15 mm length, 22 mm upper cone diameter and 12 mm bottom cone diameter. The two movable Molybdenum cathodes are fixed in Perspex insulator and placed symmetrically at two ends of the anode. The Copper emission disc of 2 mm thickness and has central aperture of different diameters is placed at the middle of the anode for ion beam exit. The inner surface of the emission disc is isolated from the anode by Perspex insulator except an area of diameter 5 mm to confine the electrical discharge in this area. A movable Faraday cup is placed at different distances from the emission electrode aperture and used to collect the output ion beam from the ion source. The working gases are admitted to the ion source through a hole in the anode via a needle valve which placed between the gas cylinder and the ion source. The optimum anode- cathode distance, the uncovered area diameter of the emission disc, the central aperture diameter of the emission electrode, the distance between emission electrode and Faraday cup have been determined using Argon gas. The optimum distances of the ion source were found to be equal to 6 mm, 5 mm, 2.5 mm, and 3 cm respectively where stable discharge current and maximum output ion beam current at low discharge current can be obtained. The discharge characteristics, ion beam characteristics, and the efficiency of the ion source have been measured at different operating conditions and different gas pressures using

  9. 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

  10. Transmission of the Neutral Beam Heating Beams at TJ-II; Transmision del Haz de Neutros de Calentamiento en TJ-II

    Energy Technology Data Exchange (ETDEWEB)

    Fuentes Lopez, C.

    2007-09-27

    Neutral beam injection heating has been development for the TJ-II stellarator. The beam has a port-through power between 700-1500 kW and injection energy 40 keV. The sensibility of the injection system to the changes of several parameters is analysed. Beam transmission is limited by losses processes since beam is born into the ions source until is coming into the fusion machine. For the beam transmission optimization several beam diagnostics have been developed. A carbon fiber composite (CFC) target calorimeter has been installed at TJ-II to study in situ the power density distribution of the neutral beams. The thermographic print of the beam can be recorded and analysed in a reliable way due to the highly anisotropic thermal conductivity of the target material. With the combined thermographic and calorimetric measurements it has been possible to determine the power density distribution of the beam. It has been found that a large beam halo is present, which can be explained by the extreme misalignment of the grids. This kind of halo has a deleterious effect on beam transport and must be minimized in order to improve the plasma heating capability of the beams. (Author) 155 refs.

  11. Cellular radiobiology of heavy-ion beams

    International Nuclear Information System (INIS)

    Tobias, C.A.; Blakely, E.A.; Ngo, F.Q.H.; Roots, R.J.; Yang, T.C.

    1981-01-01

    Progress is reported in the following areas of this research program: relative biological effectiveness and oxygen enhancement ratio of silicon ion beams; heavy ion effects on the cell cycle; the potentiation effect (2 doses of high LET heavy-ion radiations separated by 2 to 3 hours); potentially lethal damage in actively growing cells and plateau growth cells; radiation induced macromolecular lesions and cellular radiation chemistry; lethal effects of dual radiation; and the development of a biophysical repair/misrepair model

  12. 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

  13. 'Beam-emission spectroscopy' diagnostics also measure edge fast-ion light

    International Nuclear Information System (INIS)

    Heidbrink, W W; Bortolon, A; McKee, G R; Smith, D R

    2011-01-01

    Beam-emission spectroscopy (BES) diagnostics normally detect fluctuations in the light emitted by an injected neutral beam. Under some circumstances, however, light from fast ions that charge exchange in the high neutral-density region at the edge of the plasma make appreciable contributions to the BES signals. This 'passive' fast-ion D α (FIDA) light appears in BES signals from both the DIII-D tokamak and the National Spherical Torus Experiment (NSTX). One type of passive FIDA light is associated with classical orbits that traverse the edge. Another type is caused by instabilities that expel fast ions from the core; this light can complicate measurement of the instability eigenfunction.

  14. Sensibility Studies for the Neutral Beam Injection System in TJ-II

    International Nuclear Information System (INIS)

    Fuentes, C.; Liniers, M.; Guasp, J.

    1999-01-01

    The sensibility of the Neutral Beam Injection system of TJ-II to the changes of several parameters is analysed. Transmission, absorption and power loads at the intercepting structures are evaluated. The adopted values for the ion source distance, focal length and divergence are confirmed as optimal, showing a small sensitivity to changes, except for the divergence. The operational margins for beam misalignments has been found to be small but feasible, confirming also the reference directions as optimal. Finally four possible alternatives, intended to reduce the power loads at the beam entering structures, are analysed. All of them have been discarded since lead to the appearance of new risk zones, with unacceptable load levels, and reduce the transmitted power. (Author) 13 refs

  15. Funneling of low energy ion beams

    International Nuclear Information System (INIS)

    Barth, W.; Schempp, A.

    1992-01-01

    Funneling two or more beams together is a way of increasing the brightness of ion beams by filling all rf-buckets of an rf-accelerator. Thus higher current transport capability results at higher energies and operating frequencies. It can be used to reduce the cost and complexity of accelerators designed to produce intense beams with high brightness. Results of numerical simulations and funneling experiments are reported, where a setup with a 50-keV proton beam and an rf deflector is investigated to study emittance growth effects in funneling lines. (R.P.) 13 refs.; 9 figs.; 1 tab

  16. Recent progress of high-power negative ion beam development for fusion plasma heating

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Kazuhiro; Akino, Noboru; Aoyagi, Tetsuo [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment] [and others

    1997-03-01

    A negative-ion-based neutral beam injector (N-NBI) has been constructed for JT-60U. The N-NBI is designed to inject 500 keV, 10 MW neutral beams using two ion sources, each producing a 500 keV, 22 A D{sup -} ion beam. Beam acceleration test started in July, 1995 using one ion source. In the preliminary experiment, D{sup -} ion beam of 13.5 A has been successfully accelerated with an energy of 400 keV (5.4 MW) for 0.12 s at an operating pressure of 0.22 Pa. This is the highest D{sup -} beam current and power in the world. Co-extracted electron current was effectively suppressed to the ratio of Ie/I{sub D}- <1. The highest energy beam of 460 keV, 2.4 A, 0.44 s has also been obtained. Neutral beam injection starts in March, 1996 using two ion sources. To realize 1 MeV class NBI system for ITER (International Thermonuclear Experimental Reactor), demonstration of ampere class negative ion beam acceleration up to 1 MeV is an important mile stone. To achieve the mile stone, a high energy test facility called MeV Test Facility (MTF) was constructed. The system consists of a 1 MV, 1 A acceleration power supply and a 100 kW power supply system for negative ion production. Up to now, an H{sup -} ion beam was accelerated up to the energy of 805 keV with an acceleration drain current of 150 mA for 1 s in a five stage electrostatic multi-aperture accelerator. (author)

  17. Negative ion beam extraction in ROBIN

    Energy Technology Data Exchange (ETDEWEB)

    Bansal, Gourab, E-mail: bansal@ipr.res.in [Institute for Plasma Research (IPR), Bhat, Gandhinagar, Gujarat 382428 (India); Gahlaut, Agrajit; Soni, Jignesh; Pandya, Kaushal; Parmar, Kanu G.; Pandey, Ravi; Vuppugalla, Mahesh; Prajapati, Bhavesh; Patel, Amee; Mistery, Hiren [Institute for Plasma Research (IPR), Bhat, Gandhinagar, Gujarat 382428 (India); Chakraborty, Arun; Bandyopadhyay, Mainak; Singh, Mahendrajit J.; Phukan, Arindam; Yadav, Ratnakar K.; Parmar, Deepak [ITER-India, Institute for Plasma Research, A-29, Sector 25, GIDC, Gandhinagar, Gujarat 380025 (India)

    2013-10-15

    Highlights: ► A RF based negative hydrogen ion beam test bed has been set up at IPR, India. ► Ion source has been successfully commissioned and three campaigns of plasma production have been carried out. ► Extraction system (35 kV) has been installed and commissioning has been initiated. Negative ion beam extraction is immediate milestone. -- Abstract: The RF based single driver −ve ion source experiment test bed ROBIN (Replica Of BATMAN like source in INDIA) has been set up at Institute for Plasma Research (IPR), India in a technical collaboration with IPP, Garching, Germany. A hydrogen plasma of density 5 × 10{sup 12} cm{sup −3} is expected in driver region of ROBIN by launching 100 kW RF power into the driver by 1 MHz RF generator. The cesiated source is expected to deliver a hydrogen negative ion beam of 10 A at 35 kV with a current density of 35 mA/cm{sup 2} as observed in BATMAN. In first phase operation of the ROBIN ion source, a hydrogen plasma has been successfully generated (without extraction system) by coupling 80 kW RF input power through a matching network with high power factor (cos θ > 0.8) and different plasma parameters have been measured using Langmuir probes and emission spectroscopy. The plasma density of 2.5 × 10{sup 11} cm{sup −3} has been measured in the extraction region of ROBIN. For negative hydrogen ion beam extraction in second phase operation, extraction system has been assembled and installed with ion source on the vacuum vessel. The source shall be first operated in volume mode for negative ion beam extraction. The commissioning of the source with high voltage power supply has been initiated.

  18. Production of a helium beam in a focused ion beam machine using an electron beam ion trap

    International Nuclear Information System (INIS)

    Ullmann, F.; Grossmann, F.; Ovsyannikov, V. P.; Gierak, J.; Zschornack, G.

    2007-01-01

    Gallium liquid-metal ion sources that have been introduced in the late 1970s have allowed the development of a new class of micro- and nanofabrication tools collectively denominated as focused ion beam (FIB) machines. To investigate the potential of a helium beam in such a FIB instrument the authors have tested a room-temperature electron beam ion trap coupled with a high resolution FIB machine. In this letter they present their first results in target imaging using a helium beam with a resolution that allows to account for a beam diameter in the submicrometer range

  19. Ion and neutral emission from pulsed laser irradiation of metals

    Czech Academy of Sciences Publication Activity Database

    Torrisi, L.; Andó, L.; Gammino, S.; Krása, Josef; Láska, Leoš

    2001-01-01

    Roč. 184, - (2001), s. 327-336 ISSN 0168-583X Institutional research plan: CEZ:AV0Z1010921 Keywords : pulse laser irradiation * ion neutral emission * plasma * time of flight Subject RIV: BH - Optics, Masers, Laser s Impact factor: 1.041, year: 2001

  20. Beam halo collimation in heavy ion synchrotrons

    Directory of Open Access Journals (Sweden)

    I. Strašík

    2015-08-01

    Full Text Available This paper presents a systematic study of the halo collimation of ion beams from proton up to uranium in synchrotrons. The projected Facility for Antiproton and Ion Research synchrotron SIS100 is used as a reference case. The concepts are separated into fully stripped (e.g., ^{238}U^{92+} and partially stripped (e.g., ^{238}U^{28+} ion collimation. An application of the two-stage betatron collimation system, well established for proton accelerators, is intended also for fully stripped ions. The two-stage system consists of a primary collimator (a scattering foil and secondary collimators (bulky absorbers. Interaction of the particles with the primary collimator (scattering, momentum losses, and nuclear interactions was simulated by using fluka. Particle-tracking simulations were performed by using mad-x. Finally, the dependence of the collimation efficiency on the primary ion species was determined. The influence of the collimation system adjustment, lattice imperfections, and beam parameters was estimated. The concept for the collimation of partially stripped ions employs a thin stripping foil in order to change their charge state. These ions are subsequently deflected towards a dump location using a beam optical element. The charge state distribution after the stripping foil was obtained from global. The ions were tracked by using mad–x.

  1. Characterization of ion beam induced nanostructures

    International Nuclear Information System (INIS)

    Ghatak, J.; Satpati, B.; Umananda, M.; Kabiraj, D.; Som, T.; Dev, B.N.; Akimoto, K.; Ito, K.; Emoto, T.; Satyam, P.V.

    2006-01-01

    Tailoring of nanostructures with energetic ion beams has become an active area of research leading to the fundamental understanding of ion-solid interactions at nanoscale regime and with possible applications in the near future. Rutherford backscattering spectrometry (RBS), high resolution transmission electron microscopy (HRTEM) and asymmetric X-ray Bragg-rocking curve experimental methods have been used to characterize ion-induced effects in nanostructures. The possibility of surface and sub-surface/interface alloying at nano-scale regime, ion-beam induced embedding, crater formation, sputtering yield variations for systems with isolated nanoislands, semi-continuous and continuous films of noble metals (Au, Ag) deposited on single crystalline silicon will be reviewed. MeV-ion induced changes in specified Au-nanoislands on silicon substrate are tracked as a function of ion fluence using ex situ TEM. Strain induced in the bulk silicon substrate surface due to 1.5 MeV Au 2+ and C 2+ ion beam irradiation is determined by using HRTEM and asymmetric Bragg X-ray rocking curve methods. Preliminary results on 1.5 MeV Au 2+ ion-induced effects in nanoislands of Co deposited on silicon substrate will be discussed

  2. Characterization of ion beam induced nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Ghatak, J. [Institute of Physics, Sachivalaya Marg, Bhubaneswar 751 005 (India); Satpati, B. [Institute of Physics, Sachivalaya Marg, Bhubaneswar 751 005 (India); Umananda, M. [Institute of Physics, Sachivalaya Marg, Bhubaneswar 751 005 (India); Kabiraj, D. [Nuclear Science Center, Aruna Asaf Ali Marg, New Delhi 110 067 (India); Som, T. [Institute of Physics, Sachivalaya Marg, Bhubaneswar 751 005 (India); Dev, B.N. [Institute of Physics, Sachivalaya Marg, Bhubaneswar 751 005 (India); Akimoto, K. [Department of Quantum Engineering, Nagoya University, Nagoya 464-8603 (Japan); Ito, K. [Department of Quantum Engineering, Nagoya University, Nagoya 464-8603 (Japan); Emoto, T. [Toyota National College of Technology, 2-1, Toyota, Aichi 471-8525 (Japan); Satyam, P.V. [Institute of Physics, Sachivalaya Marg, Bhubaneswar 751 005 (India)]. E-mail: satyam@iopb.res.in

    2006-03-15

    Tailoring of nanostructures with energetic ion beams has become an active area of research leading to the fundamental understanding of ion-solid interactions at nanoscale regime and with possible applications in the near future. Rutherford backscattering spectrometry (RBS), high resolution transmission electron microscopy (HRTEM) and asymmetric X-ray Bragg-rocking curve experimental methods have been used to characterize ion-induced effects in nanostructures. The possibility of surface and sub-surface/interface alloying at nano-scale regime, ion-beam induced embedding, crater formation, sputtering yield variations for systems with isolated nanoislands, semi-continuous and continuous films of noble metals (Au, Ag) deposited on single crystalline silicon will be reviewed. MeV-ion induced changes in specified Au-nanoislands on silicon substrate are tracked as a function of ion fluence using ex situ TEM. Strain induced in the bulk silicon substrate surface due to 1.5 MeV Au{sup 2+} and C{sup 2+} ion beam irradiation is determined by using HRTEM and asymmetric Bragg X-ray rocking curve methods. Preliminary results on 1.5 MeV Au{sup 2+} ion-induced effects in nanoislands of Co deposited on silicon substrate will be discussed.

  3. Mutation induction by ion beams in arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Atsushi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1999-07-01

    An investigation was made on characteristics of ion beams for the biological effects and the induction of mutation using Arabidopsis plant as a model plant for the molecular genetics. Here, the characteristics of mutation at the molecular level as well as new mutants induced by ion beams were described. The ast and sep1 were obtained from the offspring of 1488 carbon ion-irradiated seeds respectively. The uvi1-uvi4 mutants were also induced from 1280 M{sub 1} lines. Thus, ion beams can induce not only known mutants such as tt, gl and hy but also novel mutants with high frequency. Even in the tt phenotype, two new mutant loci other than known loci were found. In chrysanthemum, several kinds of single, complex or stripped flower-color mutants that have been never induced by {gamma}irradiation, indicating that ion beams could produce a variety of mutants with the same phenotype. In conclusion, ion beams for the mutation induction are characterized by 1) to induce mutants with high frequency, 2) to show broad mutation spectrum and 3) to produce novel mutants. For these reasons, chemical mutagens such as EMS and low LET ionizing radiation such as X-rays and {gamma}-rays will predominantly induce many but small modifications or DNA damages on the DNA strands. As the result, several point mutations will be produced on the genome. On the contrary, ion beams as a high LET ionizing radiation will not cause so many but large and irreparable DNA damage locally, resulting in production of limited number of null mutation. (M.N.)

  4. The quest for crystalline ion beams

    CERN Document Server

    Schramm, U; Bussmann, M; Habs, D

    2002-01-01

    The phase transition of an ion beam into its crystalline state has long been expected to dramatically influence beam dynamics beyond the limitations of standard accelerator physics. Yet, although considerable improvement in beam cooling techniques has been made, strong heating mechanisms inherent to existing high-energy storage rings have prohibited the formation of the crystalline state in these machines up to now. Only recently, laser cooling of low-energy beams in the table-top rf quadrupole storage ring PAaul Laser cooLing Acceleration System (PALLAS) has lead to the experimental realization of crystalline beams. In this article, the quest for crystalline beams as well as their unique properties as experienced in PALLAS will be reviewed.

  5. Filamentation of a converging heavy ion beam

    International Nuclear Information System (INIS)

    Lee, E.P.; Buchanan, H.L.; Rosenbluth, M.N.

    1980-01-01

    A major concern in the use of heavy ion beams as igniters in pellet fusion systems is the vulnerability of the beam to the transverse flamentation instability. The undesirable consequence of this mode is the transverse heating of the beam to the extent that convergence on the pellet becomes impossible. This work considers the case of a beam injected into a gas filled reactor vessel, where finite pulse length and propagation distance play an important role in limiting growth. Two geometries are analyzed: a nonconverging case where the radius at injection is nearly equal to the desired radius at the pellet, and a converging case in which the injection radius is large and the beam is pre-focused to converge at the target. It is found that a cold beam will be severely disrupted if the product of the magnetic plasma frequency and the propagation distance is much larger than unity

  6. Neutral Probe Beam q-profile measurements in PDX and PBX-M

    International Nuclear Information System (INIS)

    Kugel, H.W.; Gammel, G.M.; Kaita, R.; Reusch, M.F.; Roberts, D.W.

    1988-06-01

    Using the Fast Ion Diagnostic Experiment (FIDE) technique, a Neutral Probe Beam (NPB) can be aimed to inject tangentially to a magnetic surface. The resultant ion orbit shifts, due to conservation of canonical toroidal angular momentum, can be measured with a multi-sightline charge-exchange analyzer to yield direct measurements of radial magnetic flux profiles, current density profiles, the radial position of the magnetic axis, flux surface inner and outer edges, q-profiles, and central-q time dependencies. An extensive error analysis was performed on previous PDX q-measurements in circular plasmas and the resulting estimated contributions of various systematic effects are discussed. Preliminary results of fast ion orbit shift measurements at early times in indented PBX-M plasmas are given. Methods for increasing the absolute experimental precision of similar measurements in progress on PBX-M are discussed. 4 refs., 3 figs

  7. Neutral beam power measurements inside the ASDEX torus

    International Nuclear Information System (INIS)

    Zengliang, Y.; Staebler, A.; Vollmer, O.

    1982-11-01

    Neutral beam power measurements inside the ASDEX torus are done with a retractable calorimeter which is only radiation cooled. The calorimeter plate made from Molybdenum is subdivided into nine segments whose increase in energy content due to a shot yields the absorbed beam power. Different models for the backward extrapolation of the measured temperature curves are examined for a series of low energy shots with the result that pure radiation cooling is a valid assumption. Furthermore, a temperature correction to the measured power is derived from these experiments. The evaluation of the shots onto this calorimeter is done by a computer program. The application of this program to a few full power shots shows that a neutral power up to 3.2 MW has been injected into the ASDEX vessel by the two injectors with an overall efficiency of up to 40%. Reionization losses due to the ASDEX stray field are less than 10%; they do not show any dependence upon the pulse length for shots up to 200 ms. (orig.)

  8. Subauroral Ion-neutral Coupling During the March 2015 Superstorm

    Science.gov (United States)

    Zhang, S.; Erickson, P. J.; Foster, J. C.; Holt, J. M.; Coster, A. J.; Makela, J. J.; Noto, J.; Meriwether, J. W.; Otsuka, Y.; Nicolls, M. J.; McCready, M. A.

    2015-12-01

    The arrival of solar Coronal Mass Ejection materials overlapping a high-speed solar wind stream originated from a nearby coronal hole caused huge magnetic disturbances during March 17-18, 2015. We have coordinated an international campaign to monitor their geospace effects using ground-based facilities, including incoherent scatter radars and Fabry-Perot Interferometers in the America sectors and other instruments in East Asia sectors, forming an observational network along approximately the 60W/120E meridional circle. The presentation will provide highlights of these observations, with a focus on the ion-neutral coupling processes at subauroral and mid-latitudes. One of the most stiking findings is the northward neutral wind surge, observed in multiple sites, accompanying strong westward winds developed at earlier times. We ascribe this unexpected wind disturbances to Subauroal Polarization Stream (SAPS) asscoated strong plasma flows driving ion-neutral coupling. SAPS and strong ion flow were observed by Millstone Hill ISR and DMSP in situ measurements. We will also report the Millstone Hill ISR observations of a significant enhancement in the storm-time molecular ion composition in the F1-region height. This enhancement appears to be caused by strong vertical ion drift due to penetration electric fields.

  9. Effect of secondary ions on the electron beam optics in the Recycler Electron Cooler

    Energy Technology Data Exchange (ETDEWEB)

    Shemyakin, A.; Prost, L.; Saewert, G.; /Fermilab

    2010-05-01

    Antiprotons in Fermilab's Recycler ring are cooled by a 4.3 MeV, 0.1-0.5 A DC electron beam (as well as by a stochastic cooling system). The unique combination of the relativistic energy ({gamma} = 9.49), an Ampere-range DC beam, and a relatively weak focusing makes the cooling efficiency particularly sensitive to ion neutralization. A capability to clear ions was recently implemented by way of interrupting the electron beam for 1-30 {micro}s with a repetition rate of up to 40 Hz. The cooling properties of the electron beam were analyzed with drag rate measurements and showed that accumulated ions significantly affect the beam optics. For a beam current of 0.3 A, the longitudinal cooling rate was increased by factor of {approx}2 when ions were removed.

  10. Burnout experiment in subcooled forced-convection boiling of water for beam dumps of a high power neutral beam injector

    International Nuclear Information System (INIS)

    Horiike, Hiroshi; Kuriyama, Masaaki; Morita, Hiroaki

    1982-01-01

    Experimental studies were made on burnout heat flux in highly subcooled forced-convection boiling of water for the design of beam dumps of a high power neutral beam injector for Japan Atomic Energy Research Institute Tokamak-60. These dumps are composed of many circular tubes with two longitudinal fins. The tube was irradiated with nonuniformly distributed hydrogen ion beams of 120 to 200 kW for as long as 10 s. The coolant water was circulated at flow velocities of 3 to 7.5 m/s at exit pressures of 0.4 to 0.9 MPa. The burnout and film-boiling data were obtained at local heat fluxes of 8 to 15 MW/m 2 . These values were as high as 2.5 times larger than those for the circumferentially uniform heat flux case with the same parameters. These data showed insensitivity to local subcooling as well as to pressure, and simple burnout correlations were derived. From these results, the beam dumps have been designed to receive energetic beam fluxes of as high as 5 MW/m 2 with a margin of a factor of 2 for burnout

  11. Ion beam processing of bio-ceramics

    International Nuclear Information System (INIS)

    Ektessabi, A.M.

    1995-01-01

    Thin films of bio-inert (TiO 2+α , Al 2 O 3+α ) and bio-active (compounds of calcium and phosphorus oxides, hydroxy-apatite) were deposited on the most commonly used implant materials such as titanium and stainless steel, using a dual-ion-beam deposition system. Rutherford backscattering spectroscopy was carried out for quantitative measurement of the interfacial atomic mixing and the composition of the elements. The experimental results show that by controlling the ion beam energy and current, thin films with very good mechanical properties are obtained as a result of the ion beam mixing within the film and at the interface of the film and substrate. (orig.)

  12. Ion beam coolers in nuclear physics

    CERN Document Server

    Äystö, J

    2003-01-01

    Cooling techniques for low-energy radioactive ion beams are reviewed together with applications on high-precision measurements of ground state properties of exotic nuclei. The emphasis in the presentation is on cooling, bunching and improving the overall characteristics of ion beams by RFQ-driven buffer gas cooling devices. Application of cooled and bunched beams in collinear laser spectroscopy to extract isotope shifts and hyperfine structure are presented with examples on radioactive Ti, Zr and Hf isotopes. The impact of the new-generation coolers on mass measurements of short-lived nuclei is discussed with examples on precision measurements of masses of super-allowed beta emitters. As a new concept, decay spectroscopy of radioactive ions trapped in a cooler Penning trap is presented.

  13. Report on the engineering test of the LBL 30 second neutral beam source for the MFTF-B project

    International Nuclear Information System (INIS)

    Vella, M.C.; Pincosy, P.A.; Hauck, C.A.; Pyle, R.V.

    1984-08-01

    Positive ion based neutral beam development in the US has centered on the long pulse, Advanced Positive Ion Source (APIS). APIS eventually focused on development of 30 second sources for MFTF-B. The Engineering Test was part of competitive testing of the LBL and ORNL long pulse sources carried out for the MFTF-B Project. The test consisted of 500 beam shots with 80 kV, 30 second deuterium, and was carried out on the Neutral Beam Engineering Test Facility (NBETF). This report summarizes the results of LBL testing, in which the LBL APIS demonstrated that it would meet the requirements for MFTF-B 30 second sources. In part as a result of this test, the LBL design was found to be suitable as the baseline for a Common Long Pulse Source design for MFTF-B, TFTR, and Doublet Upgrade

  14. Dynamics of the ion-ion acoustic instability in the thermalization of ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Han, J.H.; Horton, W. (Texas Univ., Austin, TX (United States). Inst. for Fusion Studies); Leboeuf, J.N. (Oak Ridge National Lab., TN (United States))

    1992-07-01

    Particle simulation using a nonlinear adiabatic electron response with two streaming ion species and nonlinear theory are used to study the collisionless thermalization of ion beams in a hot electron plasma. The slow beam or subsonic regime is investigated and the criterion for the transition from predominantly light ion to predominantly heavy ion heating is developed. Long-lived ion hole structures a-re observed in the final state.

  15. Ion beam dump for JT-60 NBI

    International Nuclear Information System (INIS)

    Kuriyama, Masaaki; Horiike, Hiroshi; Matsuda, Shinzaburo; Morita, Hiroaki; Shibanuma, Kiyoshi

    1981-10-01

    The design of the active cooling type ion beam dump for JT-60 NBI which receives the total beam power of 5.6 MW for 10 sec continuously is described. It is composed of array of many finned tubes which is made of oxygen free copper with 0.2% silver content. The safety margin against thermal and mechanical troubles is estimated by the heat transfer and the thermal stress calculation. (author)

  16. Ion beam processing of surgical materials

    Science.gov (United States)

    Williams, James M.; Buchanan, Raymond A.; Lee, In-Seop

    1989-02-01

    Ion beam processing has now achieved a secure place in surface treatment of biomaterials. This development is largely a result of the success of the process for wear prevention of orthopedic Ti-alloy in rubbing contact with ultrahigh molecular-weight polyethylene. Basic contributions of the authors in this area, together with other pertinent literature will be reviewed. Research in ion beam processing of biomaterials is turning to other areas. Among these, bioelectronics is considered to be a promising area for further effort. Pertinent experiments on effects of implantation of iridium into titanium and Ti-6Al-4V alloy on corrosion and charge injection properties are presented.

  17. Ion beam pulse radiolysis system at HIMAC

    Energy Technology Data Exchange (ETDEWEB)

    Chitose, N.; Katsumura, Y.; Domae, M.; Ishigure, K. [Tokyo Univ. (Japan); Murakami, T.

    1997-03-01

    An ion beam pulse radiolysis system has been constructed at HIMAC facility. Ion beam of 24MeV He{sup 2+} with the duration longer than 1 {mu}s is available for irradiation. Three kinds of aqueous solutions, (C{sub 6}H{sub 5}){sub 2}CO, NaHCO{sub 3}, and KSCN, were irradiated and the absorption signals corresponding to (C{sub 6}H{sub 5}){sub 2}CO{sup -}, CO{sub 3}{sup -}, and (SCN){sub 2}{sup -} respectively were observed. Ghost signals which interfere with the measurement are also discussed. (author)

  18. A suite of diagnostics to validate and optimize the prototype ITER neutral beam injector

    Science.gov (United States)

    Pasqualotto, R.; Agostini, M.; Barbisan, M.; Brombin, M.; Cavazzana, R.; Croci, G.; Dalla Palma, M.; Delogu, R. S.; De Muri, M.; Muraro, A.; Peruzzo, S.; Pimazzoni, A.; Pomaro, N.; Rebai, M.; Rizzolo, A.; Sartori, E.; Serianni, G.; Spagnolo, S.; Spolaore, M.; Tardocchi, M.; Zaniol, B.; Zaupa, M.

    2017-10-01

    The ITER project requires additional heating provided by two neutral beam injectors using 40 A negative deuterium ions accelerated at 1 MV. As the beam requirements have never been experimentally met, a test facility is under construction at Consorzio RFX, which hosts two experiments: SPIDER, full-size 100 kV ion source prototype, and MITICA, 1 MeV full-size ITER injector prototype. Since diagnostics in ITER injectors will be mainly limited to thermocouples, due to neutron and gamma radiation and to limited access, it is crucial to thoroughly investigate and characterize in more accessible experiments the key parameters of source plasma and beam, using several complementary diagnostics assisted by modelling. In SPIDER and MITICA the ion source parameters will be measured by optical emission spectroscopy, electrostatic probes, cavity ring down spectroscopy for H^- density and laser absorption spectroscopy for cesium density. Measurements over multiple lines-of-sight will provide the spatial distribution of the parameters over the source extension. The beam profile uniformity and its divergence are studied with beam emission spectroscopy, complemented by visible tomography and neutron imaging, which are novel techniques, while an instrumented calorimeter based on custom unidirectional carbon fiber composite tiles observed by infrared cameras will measure the beam footprint on short pulses with the highest spatial resolution. All heated components will be monitored with thermocouples: as these will likely be the only measurements available in ITER injectors, their capabilities will be investigated by comparison with other techniques. SPIDER and MITICA diagnostics are described in the present paper with a focus on their rationale, key solutions and most original and effective implementations.

  19. Cross-field injection of a charged, polarized, ion-electron beam

    International Nuclear Information System (INIS)

    Hamilton, G.W.

    1976-01-01

    An early idea for fueling a controlled fusion device had been the injection of a polarized mixture of ions and electrons across a magnetic field and into the device. Now, the beam intensity (several kA/cm 2 ) required for this technique is available from pulsed ion diodes. Remaining feasibility questions involve beam optics and trapping. The most obvious advantage over neutral-beam injection is avoidance of the need to produce high-energy atoms. Therefore, the technique will compete best at ion energies above 100 keV. The method appears feasible for pulsed startup of mirror machines, but not for steady-state injection into a plasma

  20. Progress toward a microsecond duration, repetitively pulsed, intense-ion beam

    International Nuclear Information System (INIS)

    Davis, H.A.; Olson, J.C.; Reass, W.A.; Coates, D.M.; Hunt, J.W.; Schleinitz, H.M.; Lovberg, R.H.; Greenly, J.B.

    1996-01-01

    A number of intense ion beams applications are emerging requiring repetitive high-average-power beams. These applications include ablative deposition of thin films, rapid melt and resolidification for surface property enhancement, advanced diagnostic neutral beams for the next generation of Tokamaks, and intense pulsed-neutron sources. A 200-250 keV, 15 kA, 1 μs duration, 1-30 Hz intense ion beam accelerator is being developed to address these applications. (author). 4 figs., 7 refs

  1. Beam divergence and ion current in multiaperture ion sources

    International Nuclear Information System (INIS)

    Ott, W.; Penningsfeld, F.P.

    1992-03-01

    Two different measurements of the divergence of high-current ion beams formed in a multiaperture ion source have been made. The current dependence of both measurements shows characteristic differences which are explained as a result of an inhomogeneity of the current density across the emission area. The model of Coupland et al. with a spherical beam geometry in the acceleration gap is reexamined. It is shown that a rigorous application of this model gives a beamlet defocusing in the decel electrode which is stronger by a factor of 1.35 than assumed hitherto. The implications on offset steering are discussed. (orig.)

  2. Ion beams make new blood

    International Nuclear Information System (INIS)

    Larousserie, D.

    2006-01-01

    In Russia a cyclotron has been designed and is now operating to make holes in plastic membranes: the impact of the ions produce tiny holes whose diameter is less than half a micrometer. These membranes are used in the fabrication of blood filters that are needed to separate blood corpuscles from plasma for instance. (A.C.)

  3. Treatment planning with ion beams

    International Nuclear Information System (INIS)

    Foss, M.H.

    1985-01-01

    Ions have higher linear energy transfer (LET) near the end of their range and lower LET away from the end of their range. Mixing radiations of different LET complicates treatment planning because radiation kills cells in two statistically independent ways. In some cases, cells are killed by a single-particle, which causes a linear decrease in log survival at low dosage. When the linear decrease is subtracted from the log survival curve, the remaining curve has zero slope at zero dosage. This curve is the log survival curve for cells that are killed only by two or more particles. These two mechanisms are statistically independent. To calculate survival, these two kinds of doses must be accumulated separately. The effect of each accumulated dosage must be read from its survival curve, and the logarithms of the two effects added to get the log survival. Treatment plans for doses of protons, He 3 ions, and He 4 ions suggest that these ions will be useful therapeutic modalities

  4. Ion-beam texturing of uniaxially textured Ni films

    International Nuclear Information System (INIS)

    Park, S.J.; Norton, D.P.; Selvamanickam, Venkat

    2005-01-01

    The formation of biaxial texture in uniaxially textured Ni thin films via Ar-ion irradiation is reported. The ion-beam irradiation was not simultaneous with deposition. Instead, the ion beam irradiates the uniaxially textured film surface with no impinging deposition flux, which differs from conventional ion-beam-assisted deposition. The uniaxial texture is established via a nonion beam process, with the in-plane texture imposed on the uniaxial film via ion beam bombardment. Within this sequential ion beam texturing method, grain alignment is driven by selective etching and grain overgrowth

  5. 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

  6. Fast wave current drive in neutral beam heated plasmas on DIII-D

    International Nuclear Information System (INIS)

    Petty, C.C.; Forest, C.B.; Pinsker, R.I.

    1997-04-01

    The physics of non-inductive current drive and current profile control using the fast magnetosonic wave has been demonstrated on the DIII-D tokamak. In non-sawtoothing discharges formed by neutral beam injection (NBI), the radial profile of the fast wave current drive (FWCD) was determined by the response of the loop voltage profile to co, counter, and symmetric antenna phasings, and was found to be in good agreement with theoretical models. The application of counter FWCD increased the magnetic shear reversal of the plasma and delayed the onset of sawteeth, compared to co FWCD. The partial absorption of fast waves by energetic beam ions at high harmonics of the ion cyclotron frequency was also evident from a build up of fast particle pressure near the magnetic axis and a correlated increase in the neutron rate. The anomalous fast particle pressure and neutron rate increased with increasing NBI power and peaked when a harmonic of the deuterium cyclotron frequency passed through the center of the plasma. The experimental FWCD efficiency was highest at 2 T where the interaction between the fast waves and the beam ions was weakest; as the magnetic field strength was lowered, the FWCD efficiency decreased to approximately half of the maximum theoretical value

  7. Production of highly charged ion beams from ECR ion sources

    International Nuclear Information System (INIS)

    Xie, Z.Q.

    1997-09-01

    Electron Cyclotron Resonance (ECR) ion source development has progressed with multiple-frequency plasma heating, higher mirror magnetic fields and better technique to provide extra cold electrons. Such techniques greatly enhance the production of highly charged ions from ECR ion sources. So far at cw mode operation, up to 300 eμA of O 7+ and 1.15 emA of O 6+ , more than 100 eμA of intermediate heavy ions for charge states up to Ar 13+ , Ca 13+ , Fe 13+ , Co 14+ and Kr 18+ , and tens of eμA of heavy ions with charge states to Kr 26+ , Xe 28+ , Au 35+ , Bi 34+ and U 34+ have been produced from ECR ion sources. At an intensity of at least 1 eμA, the maximum charge state available for the heavy ions are Xe 36+ , Au 46+ , Bi 47+ and U 48+ . An order of magnitude enhancement for fully stripped argon ions (I ≥ 60 enA) also has been achieved. This article will review the ECR ion source progress and discuss key requirement for ECR ion sources to produce the highly charged ion beams

  8. Profiling hydrogen in materials using ion beams

    International Nuclear Information System (INIS)

    Ziegler, J.F.; Wu, C.P.; Williams, P.

    1977-01-01

    Over the last few years many ion beam techniques have been reported for the profiling of hydrogen in materials. Nine of these were evaluated using similar samples of hydrogen ion-implanted into silicon. When possible the samples were analyzed using two or more techniques to confirm the ion-implanted accuracy. The results of this analysis which has produced a consensus profile of H in silicon which is useful as a calibration standard are reported. The analytical techniques used have capabilities ranging from very high depth resolution (approximately 50 A) and high sensitivity (less than 1 ppM) to deep probes for hydrogen which can sample throughout thin sheets

  9. Protection of neutral-beam-accelerator electrodes from spark discharges

    International Nuclear Information System (INIS)

    Praeg, W.F.

    1978-01-01

    The high-voltage (HV) electrodes of neutral beam sources (NBS's) must be protected from occasional sparks to ground. Spark currents can be limited with special transformers and reactors which introduce time delays that are long enough to quench the spark or to disconnect the energy source. A saturated time delay transformer (STDT) connected in series with the HV power supply detects spark faults and limits the current supplied by the power supply and its capacitance to ground; it also initiates spark quenching. Nonsaturated, longitudinal reactors limit the discharge current supplied by the energy stored in the circuit capacitance of the NBS filament and arc power supplies long enough to discharge this capacitance into a resistor. The design principles of these protective circuits are presented in this paper

  10. Protection of neutral-beam accelerator electrodes from spark discharges

    International Nuclear Information System (INIS)

    Praeg, W.F.

    1977-01-01

    The high-voltage (HV) electrodes of neutral beam sources (NBS's) must be protected from occasional sparks to ground. Spark currents can be limited with special transformers and reactors which introduce time delays that are long enough to quench the spark or to disconnect the energy source. A saturated time delay transformer (STDT) connected in series with the HV power supply detects spark faults and limits the current supplied by the power supply and its capacitance to ground; it also initiates spark quenching. Nonsaturated, longitudinal reactors limit the discharge current supplied by the energy stored in the circuit capacitance of the NBS filament and arc power supplies long enough to discharge this capacitance into a resistor. The design principles of these protective circuits are presented

  11. Regulated 15-V, 7500-A, neutral-beam filament supply

    International Nuclear Information System (INIS)

    Reass, W.

    1977-01-01

    Lawrence Livermore Laboratory (LLL) designed a cost-effective, regulated 15-V, 7500-A filament supply for use with the High-Voltage Test Stand , a major ERDA developmental neutral-beam test facility. The filament supply can float to 200 kV and can provide pulse widths up to 30 s. Powered by a 24-V, 0.5-TJ battery bank, it avoids the use of expensive isolation transformers and induction voltage regulators (IVR's). Battery output is regulated by a water-cooled resistor-contactor combination in which contactors are closed in sequential format to create a staircase current waveform. A fine-tuning network tunes in-between the ''steps'' for regulation to less than 0.5 percent. The regulator is digitally controlled except for the sense amplifiers, which are optically coupled to the digital controller. All ground telemetry uses optical links to minimize effects of rfi and emi noise in the data channels

  12. Power and particle balance during neutral beam injection in TFTR

    International Nuclear Information System (INIS)

    Pitcher, C.S.; Budny, R.V.; Hill, K.W.; Kilpatrick, S.J.; Manos, D.M.; Medley, S.S.; Ramsey, A.T.

    1991-05-01

    Detailed boundary plasma measurements on TFTR have been made during a NBI power scan in the range P tot = 1MW--20MW in the L-mode regime. The behavior of the plasma density left-angle n e right-angle, radiated power P rad , carbon and deuterium fluxes Γ C , Γ D , and Ζ eff can be summarized as, left-angle n e right-angle ∝ P tot 1/2 , P rad , Γ C , Γ D ∝ P tot , and Ζ eff ∼ constant. It is shown that central fuelling by the neutral beams plays a minor role in the particle balance of the discharge. More important is the NBI role in the power balance. The TFTR data during NBI originate primarily at the graphite limiter

  13. The non-neutral ion trap at Brigham Young University

    Science.gov (United States)

    Peterson, Bryan; Williams, Chad; Hall, William; Hart, Grant

    2011-10-01

    We have constructed a non-neutral ion trap with the eventual goal of measuring the rate of decay of singly-ionized 7Be. Since 7Be decays exclusively by electron capture a Malmberg-Penning trap provides an ideal environment for this measurement due to the near absence of free electrons. We will use the FTICR (Fourier Transform Ion Cyclotron Resonance) mass spectrometry technique to measure the ratio of 7Be to 7Li to determine the decay rate. We are using an enriched boron carbide target (77.7% 10B, 2.3% 11B, 20% 12C) to provide the ions for the test plasma. This allows us to test the FTICR technique through the presence of three different ions at very different concentrations. We will discuss the current status of the experiment.

  14. National Centre for Radioactive Ion Beams (NCRIB)

    International Nuclear Information System (INIS)

    Chintalapudi, S.N.

    1999-01-01

    Radioactive Ion (nuclear) Beams have become prolific recently. Nuclear physics and associated subjects have staged a comeback to almost the beginning with the advent of RIB. A dedicated National Centre for RIB (NCRIB) proposed, discussed at several forums and under serious consideration is described

  15. BEARS: Radioactive ion beams at LBNL

    International Nuclear Information System (INIS)

    Powell, J.; Guo, F.Q.; Haustein, P.E.

    1998-01-01

    BEARS (Berkeley Experiments with Accelerated Radioactive Species) is an initiative to develop a radioactive ion-beam capability at Lawrence Berkeley National Laboratory. The aim is to produce isotopes at an existing medical cyclotron and to accelerate them at the 88 inch Cyclotron. To overcome the 300-meter physical separation of these two accelerators, a carrier-gas transport system will be used. At the terminus of the capillary, the carrier gas will be separated and the isotopes will be injected into the 88 inch Cyclotron's Electron Cyclotron Resonance (ECR) ion source. The first radioactive beams to be developed will include 20-min 11 C and 70-sec 14 O, produced by (p,n) and (p,α) reactions on low-Z targets. A test program is currently being conducted at the 88 inch Cyclotron to develop the parts of the BEARS system. Preliminary results of these tests lead to projections of initial 11 C beams of up to 2.5 x 10 7 ions/sec and 14 O beams of 3 x 10 5 ions/sec

  16. Treatment Planning for Ion Beam Therapy

    Science.gov (United States)

    Jäkel, Oliver

    The special aspects of treatment planning for ion beams are outlined in this chapter, starting with positioning and immobilization of the patient, describing imaging and segmentation, definition of treatment parameters, dose calculation and optimization, and, finally, plan assessment, verification, and quality assurance.

  17. Prompt loss of beam ions in KSTAR plasmas

    Directory of Open Access Journals (Sweden)

    Jun Young Kim

    2016-10-01

    Full Text Available For a toroidal plasma facility to realize fusion energy, researching the transport of fast ions is important not only due to its close relation to the heating and current drive efficiencies but also to determine the heat load on the plasma-facing components. We present a theoretical analysis and orbit simulation for the origin of lost fast-ions during neutral beam injection (NBI heating in Korea Superconducting Tokamak Advanced Research (KSTAR device. We adopted a two-dimensional phase diagram of the toroidal momentum and magnetic moment and describe detectable momentums at the fast-ion loss detector (FILD position as a quadratic line. This simple method was used to model birth ions deposited by NBI and drawn as points in the momentum phase space. A Lorentz orbit code was used to calculate the fast-ion orbits and present the prompt loss characteristics of the KSTAR NBI. The scrape-off layer deposition of fast ions produces a significant prompt loss, and the model and experimental results closely agreed on the pitch-angle range of the NBI prompt loss. Our approach can provide wall load information from the fast ion loss.

  18. Electrostatic potential generated by perpendicular neutral-beam injection to a tokamak plasma

    Science.gov (United States)

    Yamaguchi, H.; Murakami, S.

    2018-01-01

    The electrostatic potential generated by neutral-beam-injection (NBI) heating in a tokamak plasma is investigated using numerical simulations. The density distribution of the NBI fast ions in an assumed tokamak is evaluated using the GNET drift-kinetic-equation solver which is based on the Monte Carlo method. The electrostatic potential is evaluated assuming an adiabatic response of the electrons to the fast-ion density distribution in the plasma. It is found that an electrostatic potential peak is generated near the beam-injection point owing to the trapped fast ions satisfying the zero-precession condition. An analytic model expressing the expected potential except for the peak is derived and shows a good agreement with the radial distribution and linear dependence on the electron temperature predicted by the simulation within a factor of 1–2. The existence of three-dimensional electrostatic trapping may break the poloidally-closed particle orbits, and may change the spatial distribution and transport of high-Z impurity ions.

  19. Experimental Observation of a Current-Driven Instability in a Neutral Electron-Positron Beam

    Science.gov (United States)

    Warwick, J.; Dzelzainis, T.; Dieckmann, M. E.; Schumaker, W.; Doria, D.; Romagnani, L.; Poder, K.; Cole, J. M.; Alejo, A.; Yeung, M.; Krushelnick, K.; Mangles, S. P. D.; Najmudin, Z.; Reville, B.; Samarin, G. M.; Symes, D. D.; Thomas, A. G. R.; Borghesi, M.; Sarri, G.

    2017-11-01

    We report on the first experimental observation of a current-driven instability developing in a quasineutral matter-antimatter beam. Strong magnetic fields (≥1 T ) are measured, via means of a proton radiography technique, after the propagation of a neutral electron-positron beam through a background electron-ion plasma. The experimentally determined equipartition parameter of ɛB≈10-3 is typical of values inferred from models of astrophysical gamma-ray bursts, in which the relativistic flows are also expected to be pair dominated. The data, supported by particle-in-cell simulations and simple analytical estimates, indicate that these magnetic fields persist in the background plasma for thousands of inverse plasma frequencies. The existence of such long-lived magnetic fields can be related to analog astrophysical systems, such as those prevalent in lepton-dominated jets.

  20. Experimental Observation of a Current-Driven Instability in a Neutral Electron-Positron Beam.

    Science.gov (United States)

    Warwick, J; Dzelzainis, T; Dieckmann, M E; Schumaker, W; Doria, D; Romagnani, L; Poder, K; Cole, J M; Alejo, A; Yeung, M; Krushelnick, K; Mangles, S P D; Najmudin, Z; Reville, B; Samarin, G M; Symes, D D; Thomas, A G R; Borghesi, M; Sarri, G

    2017-11-03

    We report on the first experimental observation of a current-driven instability developing in a quasineutral matter-antimatter beam. Strong magnetic fields (≥1  T) are measured, via means of a proton radiography technique, after the propagation of a neutral electron-positron beam through a background electron-ion plasma. The experimentally determined equipartition parameter of ε_{B}≈10^{-3} is typical of values inferred from models of astrophysical gamma-ray bursts, in which the relativistic flows are also expected to be pair dominated. The data, supported by particle-in-cell simulations and simple analytical estimates, indicate that these magnetic fields persist in the background plasma for thousands of inverse plasma frequencies. The existence of such long-lived magnetic fields can be related to analog astrophysical systems, such as those prevalent in lepton-dominated jets.

  1. Application of the OPTIMUS Code to the Neutral Beam Injection System of TJ-II

    International Nuclear Information System (INIS)

    Fuentes, C.; Liniers, M.; Guasp, J.

    1998-01-01

    The different losses processes affecting a neutral beam since is born into the ions source until is coming into the fusion machine, are dependent of the residual gas pressure distribution inside injector. The OPTIMUS code analyzes that losses and calculates the pressure distribution inside one injector with specific geometry. The adaptation of injector to TJ-II has not required important design changes, only the operating range of the gas flow and the pumping speed have modified. The calculations show that the required gas flows for the optimal operation of the system ned an independent pumping system for the calorimeter box with a pumping speed of 1200001/s. The system efficiency is not affected by an hypothetical beaming effect and it is found also that with a proper conditioning of the injector walls, so that the absorption coefficients do not surpass excessively the unity value, the injector operation remains optimal. (Author) 8 refs

  2. Corrected electrostatic lens systems for ion beams

    International Nuclear Information System (INIS)

    Dalgish, R.L.

    1981-01-01

    Recent work in our laboratory has introduced a new class of electrostatic focus forming element for beams, the ELCO lens. It compares favourably with the electrostatic and magnetic quadrupole elements conventionally used for microbeam formation. The ELCO lens does however have disadvantages associated with apertures and alignment. We have continued with the development of ion beam lenses and have evolved a further class of lens element which eliminates aperture and alignment problems. This new element can be combined like optical lenses into an aberration corrected system. Experimental measurement on the basic lens element has confirmed mathematical analysis of ion trajectories through the element. This mathematical analysis predicts that the basic element can be combined into a corrected lens system for, either: (1) high resolution microprobe formation with intrinsic rastering ability, the spot size limited only by the beam properties; or (2) high quality image formation with large magnification/demagnification ratio and wide angular aperture. (orig.)

  3. Monte Carlo simulation of neutral beam injection in the Wendelstein VII-A stellarator

    International Nuclear Information System (INIS)

    Maassberg, H.

    1986-06-01

    Strong neutral beam heating in the W VII-A stellarator with injection nearly perpendicular to the magnetic field results in a high energy ion tail. In a simplified model, the full nonlinear Fokker-Planck equation based on Coulomb interactions is solved self-consistently by means of Monte Carlo techniques. Generalized scattering operators which are equivalent to the nonlinear Fokker-Planck collision term are derived. With the numerical simulation, the strong neutral beam heating is analyzed for a typical discharge in W VII-A with H 0 injection in a H + /D + plasma mixture for stationary conditions. Both deuterium and hydrogen distribution functions are calculated. The D + distribution is found to be highly isotropic, the deviation from a Maxwellian resulting mainly from electron cooling. Furthermore, ion heat conduction is of minor importance for the energy balance of the bulk part of the plasma. The H + distribution, however, develops a strong pressure anisotropy, which can also be deduced experimentally from the diamagnetic signal. (orig.)

  4. High heat flux engineering for the upgraded neutral beam injection systems of MAST-U

    Energy Technology Data Exchange (ETDEWEB)

    Dhalla, F., E-mail: Fahim.dhalla@ccfe.ac.uk; Mistry, S.; Turner, I.; Barrett, T.R.; Day, I.; McAdams, R.

    2015-10-15

    Highlights: • A new Residual Ion Dump (RID) and bend magnet system for the upgraded NBI systems have been designed for the 5 s MAST-U pulse requirements. • Design scoping was performed using numerical ion-tracing analysis software (MAGNET and OPERA codes). • A more powerful bending magnet will separate the residual ions into full, half and third energy components. • Three separate CuCrZr dumps spread the power loading resulting in acceptable power footprints. • FE thermo-mechanical analyses using ANSYS to validate the designs against the ITER SDC-IC code. • New bend magnet coils, yoke and CuCrZr water-cooled plates are in the procurement phase. - Abstract: For the initial phase of MAST-U operation the two existing neutral beam injection systems will be used, but must be substantially upgraded to fulfil expected operational requirements. The major elements are the design, manufacture and installation of a bespoke bending magnet and Residual Ion Dump (RID) system. The MAST-design full energy dump is being replaced with new actively-cooled full, half and third energy dumps, designed to receive 2.4 MW of ion power deflected by an iron-cored electromagnet. The main design challenge is limited space available in the vacuum vessel, requiring ion-deflection calculations to ensure acceptable heat flux distribution on the dump panels. This paper presents engineering and physics analysis of the upgraded MAST beamlines and reports the current status of manufacture.

  5. Measurement of neutral current coherent neutral pion production on carbon in a few-GeV neutrino beam

    International Nuclear Information System (INIS)

    2010-01-01

    The SciBooNE Collaboration reports a measurement of neutral current coherent neutral pion production on carbon by a muon neutrino beam with average energy 0.8 GeV. The separation of coherent from inclusive neutral pion production has been improved by detecting recoil protons from resonant neutral pion production. We measure the ratio of the neutral current coherent neutral pion production to total charged current cross sections to be (1.16 +/- 0.24) x 10-2. The ratio of charged current coherent pion to neutral current coherent pion production is calculated to be 0.14+0.30 -0.28, using our published charged current coherent pion measurement.

  6. High repetition rate intense ion beam source

    International Nuclear Information System (INIS)

    Hammer, D.A.; Glidden, S.C.; Noonan, B.

    1992-01-01

    This final report describes a ≤ 150kV, 40kA, 100ns high repetition rate pulsed power system and intense ion beam source which is now in operation at Cornell University. Operation of the Magnetically-controlled Anode Plasma (MAP) ion diode at > 100Hz (burst mode for up to 10 pulse bursts) provides an initial look at repetition rate limitations of both the ion diode and beam diagnostics. The pulsed power systems are capable of ≥ 1kHz operation (up to 10 pulse bursts), but ion diode operation was limited to ∼100Hz because of diagnostic limitations. By varying MAP diode operating parameters, ion beams can be extracted at a few 10s of keV or at up to 150keV, the corresponding accelerating gap impedance ranging from about 1Ω to about 10Ω. The ability to make hundreds of test pulses per day at an average repetition rate of about 2 pulses per minute permits statistical analysis of diode operation as a function of various parameters. Most diode components have now survived more than 10 4 pulses, and the design and construction of the various pulsed power components of the MAP diode which have enabled us to reach this point are discussed. A high speed data acquisition system and companion analysis software capable of acquiring pulse data at 1ms intervals (in bursts of up to 10 pulses) and processing it in ≤ min is described

  7. Ion beam analysis of metal ion implanted surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Evans, P.J.; Chu, J.W.; Johnson, E.P.; Noorman, J.T. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Sood, D.K. [Royal Melbourne Inst. of Tech., VIC (Australia)

    1993-12-31

    Ion implantation is an established method for altering the surface properties of many materials. While a variety of analytical techniques are available for the characterisation of implanted surfaces, those based on particle accelerators such as Rutherford backscattering (RBS) and nuclear reaction analysis (NRA) provide some of the most useful and powerful for this purpose. Application of the latter techniques to metal ion implantation research at ANSTO will be described with particular reference to specific examples from recent studies. Where possible, the information obtained from ion beam analysis will be compared with that derived from other techniques such as Energy Dispersive X-ray (EDX) and Auger spectroscopies. 4 refs., 5 figs.

  8. Anomalous electron heating and energy balance in an ion beam generated plasma

    Energy Technology Data Exchange (ETDEWEB)

    Guethlein, G.

    1987-04-01

    The plasma described in this report is generated by a 15 to 34 kV ion beam, consisting primarily of protons, passing through an H/sub 2/ gas cell neutralizer. Plasma ions (or ion-electron pairs) are produced by electron capture from (or ionization of) gas molecules by beam ions and atoms. An explanation is provided for the observed anomalous behavior of the electron temperature (T/sub e/): a step-lite, nearly two-fold jump in T/sub e/ as the beam current approaches that which minimizes beam angular divergence; insensitivity of T/sub e/ to gas pressure; and the linear relation of T/sub e/ to beam energy.

  9. On Auger neutralization of He sup + ions on a Ag(111) surface

    CERN Document Server

    Monreal, R C; Esaulov, V A

    2003-01-01

    Neutralization of He sup + ions in grazing incidence scattering on Ag(111) is studied. A small scattered ion fraction is observed. The experimental results are discussed in terms of survival from Auger neutralization, whose rates are derived theoretically. Molecular dynamics simulations of scattered ion trajectories are performed and the surviving ion fractions are then calculated using the theoretically estimated Auger neutralization rates. The calculations agree quite well with the experimental data and empirical estimates of the neutralization rates.

  10. Ion-Beam-Excited, Electrostatic, Ion Cyclotron Instability

    DEFF Research Database (Denmark)

    Michelsen, Poul; Pécseli, Hans; Juul Rasmussen, Jens

    1977-01-01

    The stability limits of the ion‐beam‐excited, electrostatic, ion cyclotron instability were investigated in a Q‐machine plasma where the electrons could be heated by microwaves. In agreement with theory, the beam energy necessary for excitation decreased with increasing electron temperature....

  11. Ion-Beam-Excited Electrostatic Ion Cyclotron Instability

    DEFF Research Database (Denmark)

    Michelsen, Poul; Pécseli, Hans; Juul Rasmussen, Jens

    1977-01-01

    The stability limits of the ion‐beam‐excited, electrostatic, ion cyclotron instability were investigated in a Q‐machine plasma where the electrons could be heated by microwaves. In agreement with theory, the beam energy necessary for excitation decreased with increasing electron temperature....

  12. Initial Neutral Particle Analyzer Measurements of Ion Temperature in NSTX

    Energy Technology Data Exchange (ETDEWEB)

    S.S. Medley; R.E. Bell; M.P. Petrov; A.L. Roquemore; and E.V. Suvorkin

    2002-07-08

    The Neutral Particle Analyzer (NPA) diagnostic on the National Spherical Torus Experiment (NSTX) utilizes a PPPL-designed E||B spectrometer which measures the energy spectra of minority H and bulk D species simultaneously with 39 energy channels per mass specie and a time resolution of 1 msec. The calibrated energy range is E = 0.5-150 keV and the energy resolution varies from (delta)E/E = 3-7% over the surface of the microchannel plate detector. The NPA measures thermal Maxwellian ion spectra to obtain line integrated ion temperatures, T{sub i}. For line integral electron densities below neL {approx} 3.5 x 10{sup 19} m{sup -2}, good agreement is observed between the line integrated NPA T{sub i} and the central T{sub i}(0) measured by the spatially localized CHarge Exchange Recombination Spectroscopy (CHERS) diagnostic. However, with increasingly higher n{sub eL} the NPA T{sub i} falls below the central T{sub i}(0) measured by CHERS because the charge exchange neutral emissivity weights the line integrated NPA measurement outboard of the plasma core. An analytic neutral analysis code, DOUBLE, has been applied to the NPA data to correct for this effect and restore agreement with T{sub i}(0) measured by CHERS. A description of the NPA diagnostic on NSTX and initial ion temperature measurements along with an illustration of application of the DOUBLE code are presented.

  13. Study on broad beam heavy ion CT

    International Nuclear Information System (INIS)

    Ohno, Yumiko; Kohno, Toshiyuki; Sasaki, Hitomi; Nanbu, S.; Kanai, Tatsuaki

    2003-01-01

    To achieve the heavy ion radiotherapy more precisely, it is important to know the distribution of the electron density in a human body, which is highly related to the range of charged particles. From a heavy ion CT image, we can directly obtain the 2-D distribution of the electron density in a sample. For this purpose, we have developed a broad beam heavy ion CT system. The electron density was obtained using some kinds of solutions targets. Also the dependence of the spatial resolution on the target size and the kinds of beams was estimated in this work using cylinders targets of 40, 60 and 80 mm in diameter, each of them has a hole of 10 mm in diameter at the center of it. (author)

  14. Fast control and data acquisition in the neutral beam test facility

    Energy Technology Data Exchange (ETDEWEB)

    Luchetta, A., E-mail: adriano.luchetta@igi.cnr.it; Manduchi, G.; Taliercio, C.

    2014-05-15

    Highlights: • The paper describes the fast control and data acquisition in the ITER neutral beam test facility. • The usage of real time control in ion beam generation and extraction is proposed. • Real time management of breakdowns is described. • The implementation of event-driven data acquisition is reported. - Abstract: Fast control and data acquisition are required in the ion source test bed of the ITER neutral beam test facility, referred to as SPIDER. Fast control will drive the operation of the power supply systems with particular reference to special asynchronous events, such as the breakdowns. These are short-circuits among grids or between grids and vessel that can occur repeatedly during beam operation. They are normal events and, as such, they will be managed by the fast control system. Cycle time associated to such fast control is down to hundreds of microseconds. Fast data acquisition is required when breakdowns occur. Event-driven data acquisition is triggered in real time by fast control at the occurrence of each breakdown. Pre- and post-event samples are acquired, allowing capturing information on transient phenomena in a whole time-window centered on the event. Sampling rate of event-driven data acquisition is up to 5 MS/s. Fast data acquisition may also be independent of breakdowns as in the case of the cavity ring-down spectroscopy where data chunks are acquired at 100 MS/s in bursts of 1.5 ms every 100 ms and are processed in real time to produce derived measurements. The paper after the description of the SPIDER fast control and data acquisition application will report the system design based on commercially available hardware and the MARTe and MDSplus software frameworks. The results obtained by running a full prototype of the fast control and data acquisition system are also reported and discussed. They demonstrate that all SPIDER fast control and data acquisition requirements can be met in the prototype solution.

  15. Study of negative hydrogen ion beam optics using the 3D3V PIC model

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, K., E-mail: kmiyamot@naruto-u.ac.jp [Naruto University of Education, 748 Nakashima, Takashima, Naruto-cho, Naruto-shi, Tokushima, 772-8502 (Japan); Nishioka, S.; Goto, I.; Hatayama, A. [Faculty of Science and Technology, Keio University, 3-14-1, Hiyoshi, Kohoku-ku, Yokohama, 223-8522 (Japan); Hanada, M.; Kojima, A. [Japan Atomic Energy Agency, 801-1,Mukoyama, Naka, 319-0913 (Japan)

    2015-04-08

    The mechanism of negative ion extraction under real conditions with the complex magnetic field is studied by using the 3D PIC simulation code. The extraction region of the negative ion source for the negative ion based neutral beam injection system in fusion reactors is modelled. It is shown that the E x B drift of electrons is caused by the magnetic filter and the electron suppression magnetic field, and the resultant asymmetry of the plasma meniscus. Furthermore, it is indicated that that the asymmetry of the plasma meniscus results in the asymmetry of negative ion beam profile including the beam halo. It could be demonstrated theoretically that the E x B drift is not significantly weakened by the elastic collisions of the electrons with neutral particles.

  16. Ions kinematics in an electrostatic ion beam trap

    Energy Technology Data Exchange (ETDEWEB)

    Attia, D

    2004-06-01

    In this study, I have tried to provide a better understanding of the dynamics of ions inside an electrostatic ion beam trap. The electrostatic ion trap allows to store ions moving between two electrostatic mirrors. Although the trap has been developed already seven years ago, no direct measurement of the transversal velocity distribution of the ions has been performed. Such quantity is central for understanding the conditions under which a beam should be produced (mainly emittance) in order to be trapped by such a device. The data I have obtained during the course of this work are based on an experimental technique which relies on the direct imaging of the particles exiting the trap, as well as on numerical simulations of the ion trajectories inside the trap. I have personally been involved in the hardware development of the imaging system, the data acquisition and analysis of the data as well as il all numerical calculations presented here. These results allow us to obtain, for the first time, experimental information on the transverse phase space of the trap, and contribute to the overall understanding of the ion motion in this system. (author)

  17. Heat flux to the limiter during disruptions and neutral beam injection in Doublet-III

    International Nuclear Information System (INIS)

    Hino, T.; DeGrassie, J.; Taylor, T.S.; Hopkins, G.; Meyer, C.; Petrie, T.W.; Kahn, C.L.; Ejima, S.

    1984-01-01

    The heat flux to the Doublet-III primary limiter has been monitored during plasma disruptions and during neutral beam injection. The surface temperature of the movable TiC-coated graphite limiter was measured with an Inframetrics thermal imaging system and a suitably filtered silicon photodiode spot detector. In addition, the floating electric potential of the limiter with respect to the vacuum vessel was measured. The heat pulse duration to the limiter was measured by the spot detector with a time response of x approx.= 10 μs and these times were correlated with the plasma parameters. In limiter discharges, 20% of the plasma kinetic stored energy goes to the limiter during disruptions. The power balance during disruptions is also discussed. During neutral beam injection, the limiter is not heated uniformly; the ion drift side receives much more thermal flux than the electron drift side. The fraction of beam power going to the limiter is as high as approx.= 35% in normal limiter discharges. (orig.)

  18. Heat-exchanger concepts for neutral-beam calorimeters

    International Nuclear Information System (INIS)

    Thompson, C.C.; Polk, D.H.; McFarlin, D.J.; Stone, R.

    1981-01-01

    Advanced cooling concepts that permit the design of water cooled heat exchangers for use as calorimeters and beam dumps for advanced neutral beam injection systems were evaluated. Water cooling techniques ranging from pool boiling to high pressure, high velocity swirl flow were considered. Preliminary performance tests were carried out with copper, inconel and molybdenum tubes ranging in size from 0.19 to 0.50 in. diameter. Coolant flow configurations included (1) smooth tube/straight flow, (2) smooth tube with swirl flow created by tangential injection of the coolant, and (3) axial flow in internally finned tubes. Additionally, the effect of tube L/D was evaluated. A CO 2 laser was employed to irradiate a sector of the tube exterior wall; the laser power was incrementally increased until burnout (as evidenced by a coolant leak) occurred. Absorbed heat fluxes were calculated by dividing the measured coolant heat load by the area of the burn spot on the tube surface. Two six element thermopiles were used to accurately determine the coolant temperature rise. A maximum burnout heat flux near 14 kW/cm 2 was obtained for the molybdenum tube swirl flow configuration

  19. DIII-D Neutral Beam control system operator interface

    International Nuclear Information System (INIS)

    Harris, J.J.; Campbell, G.L.

    1993-10-01

    A centralized graphical user interface has been added to the DIII-D Neutral Beam (NB) control systems for status monitoring and remote control applications. This user interface provides for automatic data acquisition, alarm detection and supervisory control of the four NB programmable logic controllers (PLC) as well as the Mode Control PLC. These PLCs are used for interlocking, control and status of the NB vacuum pumping, gas delivery, and water cooling systems as well as beam mode status and control. The system allows for both a friendly user interface as well as a safe and convenient method of communicating with remote hardware that formerly required interns to access. In the future, to enable high level of control of PLC subsystems, complete procedures is written and executed at the touch of a screen control panel button. The system consists of an IBM compatible 486 computer running the FIX DMACS trademark for Windows trademark data acquisition and control interface software, a Texas Instruments/Siemens communication card and Phoenix Digital optical communications modules. Communication is achieved via the TIWAY (Texas Instruments protocol link utilizing both fiber optic communications and a copper local area network (LAN). Hardware and software capabilities will be reviewed. Data and alarm reporting, extended monitoring and control capabilities will also be discussed

  20. Analysis of secondary particle behavior in multiaperture, multigrid accelerator for the ITER neutral beam injector.

    Science.gov (United States)

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

    2010-02-01

    Heat load on acceleration grids by secondary particles such as electrons, neutrals, and positive ions, is a key issue for long pulse acceleration of negative ion beams. Complicated behaviors of the secondary particles in multiaperture, multigrid (MAMuG) accelerator have been analyzed using electrostatic accelerator Monte Carlo code. The analytical result is compared to experimental one obtained in a long pulse operation of a MeV accelerator, of which second acceleration grid (A2G) was removed for simplification of structure. The analytical results show that relatively high heat load on the third acceleration grid (A3G) since stripped electrons were deposited mainly on A3G. This heat load on the A3G can be suppressed by installing the A2G. Thus, capability of MAMuG accelerator is demonstrated for suppression of heat load due to secondary particles by the intermediate grids.

  1. Research and development of advanced materials using ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Namba, Susumu [Nagasaki Inst. of Applied Science, Nagasaki (Japan)

    1997-03-01

    A wide range of research and development activities of advanced material synthesis using ion beams will be discussed, including ion beam applications to the state-of-the-art electronics from giant to nano electronics. (author)

  2. Ion beam heating for fast ignition

    International Nuclear Information System (INIS)

    Gus'kov, S.Yu.; Limpouch, J.; Klimo, O.

    2010-01-01

    Complete text of publication follows. The characteristics features of the formation of the spatial distribution of the energy transferred to the plasma from a beam of ions with different initial energies, masses and charges under fast ignition conditions are determined. The motion of the Bragg peak is extended with respect to the spatial distribution of the temperature of the ion-beam-heated medium. The parameters of the ion beams are determined to initiate different regimes of fast ignition of thermonuclear fuel precompressed to a density of 300-500 g/cm 3 - the edge regime, in which the ignition region is formed at the outer boundary of the fuel, and the internal regime, in which the ignition region is formed in central parts of the fuel. The conclusion on the requirements for fast ignition by light and heavy ion beams is presented. It is shown that the edge heating with negative temperature gradient is described by a self-similar solution. Such a temperature distribution is the reason of the fact that the ignited beam energy at the edge heating is larger than the minimal ignition energy by factor 1.65. The temperature Bragg peak may be produced by ion beam heating in the reactor scale targets with pR-parameter larger than 3-4 g/cm 2 . In particular, for central ignition of the targets with pR-parameters in the range of 4-8 g/cm 2 the ion beam energy should be, respectively, from 5 to 7 times larger than the minimal ignition energy. The work by S.Ye. Gus'kov, D.V. Il'in, and V.E. Sherman was supported by the Ministry of Education and Science of the Russian Federation under the program 'Development of the Scientific Potential of High Education for 2009-2010' (project no. 2.1.1/1505) and the Russian Foundation for Basic Research (project no. 08-02-01394 a ). The work by J. Limpouch and O. Klimo was supported by the Czech Ministry of Education (project no. LC528, MSM6840770022).

  3. Applications of ion beam analysis workshop. Workshop handbook

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    A workshop on applications of ion beam analysis was held at ANSTO, immediate prior to the IBMM-95 Conference in Canberra. It aims was to review developments and current status on use of ion beams for analysis, emphasizing the following aspects: fundamental ion beam research and secondary effects of ion beams; material sciences, geological, life sciences, environmental and industrial applications; computing codes for use in accelerator research; high energy heavy ion scattering and recoil; recent technological development using ion beams. The handbook contains the workshop`s program, 29 abstracts and a list of participants.

  4. Applications of ion beam analysis workshop. Workshop handbook

    International Nuclear Information System (INIS)

    1995-01-01

    A workshop on applications of ion beam analysis was held at ANSTO, immediate prior to the IBMM-95 Conference in Canberra. It aims was to review developments and current status on use of ion beams for analysis, emphasizing the following aspects: fundamental ion beam research and secondary effects of ion beams; material sciences, geological, life sciences, environmental and industrial applications; computing codes for use in accelerator research; high energy heavy ion scattering and recoil; recent technological development using ion beams. The handbook contains the workshop's program, 29 abstracts and a list of participants

  5. Intensive Ion Beam In Storage Rings With Electron Cooling

    CERN Document Server

    Korotaev, Yu V; Kamerdjiev, V; Maier, R; Meshkov, I; Noda, K; Prasuhn, D; Sibuya, S; Sidorin, A; Stein, H J; Stockhorst, H; Syresin, E M; Uesugi, T

    2004-01-01

    Results of experimental studies of the electron cooling of a proton beam at COSY (Juelich, Germany) and an ion beam at HIMAC (Chiba, Japan) are presented. Intensity of the ion beam is limited by two general effects: particle loss directly after the injection and development of instability in a deep cooled ion beam. Methods of the instability suppression, which allow increasing the cooled beam intensity, are described.

  6. Image-projection ion-beam lithography

    International Nuclear Information System (INIS)

    Miller, P.A.

    1989-01-01

    Image-projection ion-beam lithography is an attractive alternative for submicron patterning because it may provide high throughput; it uses demagnification to gain advantages in reticle fabrication, inspection, and lifetime; and it enjoys the precise deposition characteristics of ions which cause essentially no collateral damage. This lithographic option involves extracting low-mass ions (e.g., He + ) from a plasma source, transmitting the ions at low voltage through a stencil reticle, and then accelerating and focusing the ions electrostatically onto a resist-coated wafer. While the advantages of this technology have been demonstrated experimentally by the work of IMS (Austria), many difficulties still impede extension of the technology to the high-volume production of microelectronic devices. We report a computational study of a lithography system designed to address problem areas in field size, telecentricity, and chromatic and geometric aberration. We present a novel ion-column-design approach and conceptual ion-source and column designs which address these issues. We find that image-projection ion-beam technology should in principle meet high-volume-production requirements. The technical success of our present relatively compact-column design requires that a glow-discharge-based ion source (or equivalent cold source) be developed and that moderate further improvement in geometric aberration levels be obtained. Our system requires that image predistortion be employed during reticle fabrication to overcome distortion due to residual image nonlinearity and space-charge forces. This constitutes a software data preparation step, as do correcting for distortions in electron lithography columns and performing proximity-effect corrections. Areas needing further fundamental work are identified

  7. Development of a beam ion velocity detector for the heavy ion beam probe

    International Nuclear Information System (INIS)

    Fimognari, P. J.; Crowley, T. P.; Demers, D. R.

    2016-01-01

    In an axisymmetric plasma, the conservation of canonical angular momentum constrains heavy ion beam probe (HIBP) trajectories such that measurement of the toroidal velocity component of secondary ions provides a localized determination of the poloidal flux at the volume where they originated. We have developed a prototype detector which is designed to determine the beam angle in one dimension through the detection of ion current landing on two parallel planes of detecting elements. A set of apertures creates a pattern of ion current on wires in the first plane and solid metal plates behind them; the relative amounts detected by the wires and plates determine the angle which beam ions enter the detector, which is used to infer the toroidal velocity component. The design evolved from a series of simulations within which we modeled ion beam velocity changes due to equilibrium and fluctuating magnetic fields, along with the ion beam profile and velocity dispersion, and studied how these and characteristics such as the size, cross section, and spacing of the detector elements affect performance.

  8. Design of the calorimeter and beam dump for the TFTR prototype neutral beam injector

    International Nuclear Information System (INIS)

    Stone, R.R.; Haughian, J.M.

    1977-01-01

    A calorimeter has been designed for use with the TFTR prototype neutral beam injection system. It consists of three vees each having two 18.8-mm-thick (0.75 in.) copper plates at a 6-deg angle, relative to the beam centerline. The maximum power density on a plate with this arrangement will be 2.0 kW/cm 2 , resulting in a front surface temperature rise of about 420 0 C. A support and retraction system moves the calorimeter in and out of the beam centerline. Various factors used in the selection of the absorber plate material will be discussed and also some experimental test results will be presented

  9. Progress toward a microsecond duration, repetitive, intense-ion beam for active spectroscopic measurements on ITER

    Energy Technology Data Exchange (ETDEWEB)

    Davis, H.A.; Bartsch, R.R.; Barnes, C.W. [and others

    1996-06-01

    The authors describe the design of an intense, pulsed, repetitive, neutral beam based on magnetically insulated diode technology for injection into ITER for spectroscopic measurements of thermalizing alpha particle and thermal helium density profiles, ion temperature, plasma rotation, and low Z impurity concentrations in the confinement region. The beam is being developed to enhance low signal-to-noise ratios expected with conventional steady-state ion beams because of severe beam attenuation and intense bremstrahlung emission. A 5 GW (e.g., 100 keV, 50 kA) one-microsecond-duration beam would increase the signal by 10{sup 3} compared to a conventional 5 MW beam with signal-to-noise ratios comparable to those from a chopped conventional beam in one second.

  10. MEV Energy Electrostatic Accelerator Ion Beam Emittance Measurement

    OpenAIRE

    I.G. Ignat’ev; M.I. Zakharets; S.V. Kolinko; D.P. Shulha

    2014-01-01

    The testing equipment was designed, manufactured and tried out permitting measurements of total current, current profile and emittance of an ion beam extracted from the ion beam. MeV energy electrostatic accelerator ion H + beam emittance measurement results are presented.

  11. Evaluation of tritium diffusion through the Neutral Beam Injector calorimeter panel

    Energy Technology Data Exchange (ETDEWEB)

    Borgognoni, Fabio [ENEA, Dipartimento Fusione Tecnologie e Presidio Nucleare, C.R. ENEA Frascati, Via E. Fermi 45, Frascati (RM) I-00044 (Italy)], E-mail: fabio.borgognoni@frascati.enea.it; Moriani, Andrea [ENEA, Dipartimento Fusione Tecnologie e Presidio Nucleare, C.R. ENEA Frascati, Via E. Fermi 45, Frascati (RM) I-00044 (Italy); Sandri, Sandro [ENEA, Dipartimento Biotecnologie, Agroindustria e Protezione della Salute Istituto di Radioprotezione - C.R. ENEA Frascati, Via E. Fermi 45, Frascati (RM) I-00044 (Italy); Tosti, Silvano [ENEA, Dipartimento Fusione Tecnologie e Presidio Nucleare, C.R. ENEA Frascati, Via E. Fermi 45, Frascati (RM) I-00044 (Italy)

    2009-06-15

    The Neutral Beam Test Facility (NBTF) to be realized in Padoa will test the Neutral Beam Injection (NBI), one of the Heating and Current Drive Systems foreseen for ITER. The NBI is based on the acceleration of hydrogen or deuterium negative ions up to 1 MeV. This work has been aimed at assessing the tritium release from the NBTF in order to provide data for the safety analysis. In particular, the diffusion of the tritium through the neutral beam target material (the CuCrZr alloy calorimeter panels) has been assessed by using literature data of the diffusion coefficient. The tritium generated inside the calorimeter panels moves into both the vacuum and water side: the tritium diffusion flux has been evaluated during the beam-on (200 deg. C) and the beam-off (20 deg. C) phases of the NBTF experiments consisting of an interim campaign and a final test. The penetration depth of the tritium through the 2 mm thick CuCrZr alloy material has been also evaluated by using a Monte-Carlo code. As main result, the assessed diffusion flux of tritium during both the beam-on and the beam-off phases are modest. In fact, at the end of the interim campaign (100 days), about the 96% of the all generated tritium (626.5 MBq) exits the calorimeter while the residual tritium inventory (25 MBq) leaves the copper alloy with a diffusion time of about 1 month. At the end of the final test (14 days) about the 99% of the total generated tritium (1.023 x 10{sup 4} MBq) leaves the copper alloy and the remaining tritium inventory (152.2 MBq) is released by about 32 days. In both the interim campaign and the final test, more than the 99% of the total tritium is transferred into the vacuum side of the calorimeter panel while negligible tritium amounts enter the cooling water system thus showing a very low impact on the environ0010me.

  12. Funnel cone for focusing intense ion beams on a target

    International Nuclear Information System (INIS)

    Bieniosek, F.M.; Henestroza, E.; Ni, P.

    2009-01-01

    We describe a funnel cone for concentrating an ion beam on a target. The cone utilizes the reflection characteristic of ion beams on solid walls to focus the incident beam andincrease beam intensity on target. The cone has been modeled with the TRIM code. A prototype has been tested and installed for use in the 350-keV K+ NDCX target chamber.

  13. NSUF Ion Beam Investment Options Workshop Report

    Energy Technology Data Exchange (ETDEWEB)

    Heidrich, Brenden John [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-03-01

    The workshop that generated this data was convened to develop a set of recommendations (a priority list) for possible funding in the area of US domestic ion beam irradiation capabilities for nuclear energy-focused RD&D. The results of this workshop were intended for use by the Department of Energy - Office of Nuclear Energy (DOE-NE) for consideration of support for these facilities. The workshop considered, as part of the initial potential future support discussions, input submitted through the Office of Nuclear Energy Request for Information (RFI) (DE-SOL-0008318, April 13, 2015), but welcomed discussion (and presentation) of other options, whether specific or general in scope. Input from users, including DOE-NE program interests and needs for ion irradiation RD&D were also included. Participants were selected from various sources: RFI respondents, NEUP/NEET infrastructure applicants, universities with known expertise in nuclear engineering and materials science and other developed sources. During the three days from March 22-24, 2016, the workshop was held at the Idaho National Laboratory Meeting Center in the Energy Innovation Laboratory at 775 University Drive, Idaho Falls, ID 83401. Thirty-one members of the ion beam community attended the workshop, including 15 ion beam facilities, six representatives of Office of Nuclear Energy R&D programs, an industry representative from EPRI and the chairs of the NSUF User’s Organization and the NSUF Scientific Review Board. Another four ion beam users were in attendance acting as advisors to the process, but did not participate in the options assessment. Three members of the sponsoring agency, the Office of Science and Technology Innovation (NE-4) also attended the workshop.

  14. 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

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

    Science.gov (United States)

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

    2014-02-01

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

  16. Funneling of low energy ion beams

    International Nuclear Information System (INIS)

    Barth, W.; Schempp, A.

    1992-01-01

    Funneling is a way of increasing the brightness of ion beams by filling all buckets of a rf-accelerator and using the higher current transport capability at higher energies. Funnel systems have been proposed, e.g. for HIIF type drivers and spallation neutron sources. Results of numerical simulations and funneling experiments at Frankfurt are reported, where a setup with a 50 keV proton beam and a rf deflector is investigated to study especially emittance growth effects in funneling lines. (Author) 9 figs., tab., 13 refs

  17. Ion beam irradiation effects on aromatic polymers

    International Nuclear Information System (INIS)

    Shukushima, Satoshi; Ueno, Keiji

    1995-01-01

    We studied the optical and thermal properties of aromatic polymer films which had been irradiated with 1 MeV H + , H 2 + and He + ions. The examined aromatic polymers were polyetherether ketone(PEEK), polyetherimide(PEI), polyether sulfon(PES), polysulfon(PSF), and polyphenylene sulfide(PPS). The optical densities at 300nm of PES and PSF greatly increased after the irradiation. The optical densities at 400nm of all the examined polymer lineally increased with the irradiation dose. The PEEK film which had been irradiated with 1 MeV H + was not deformed above melting point. This demonstrates that cross-linking occurs in PEEK films by ion beam irradiation. As for the effects, depending on the mass of the irradiated ions, it was found that the ions with a high mass induced larger effects on the aromatic polymers for the same absorption energy. (author)

  18. Surface generation of negative hydrogen ion beams

    International Nuclear Information System (INIS)

    Bommel, P.J.M. van.

    1984-01-01

    This thesis describes investigations on negative hydrogen ion sources at the ampere level. Formation of H - ions occurs when positive hydrogen ions capture two electrons at metal surfaces. The negative ionization probability of hydrogen at metal surfaces increases strongly with decreasing work function of the surface. The converters used in this study are covered with cesium. Usually there are 'surface plasma sources' in which the hydrogen source plasma interacts with a converter. In this thesis the author concentrates upon investigating a new concept that has converters outside the plasma. In this approach a positive hydrogen ion beam is extracted from the plasma and is subsequently reflected from a low work function converter surface. (Auth.)

  19. Chemistry of sprite discharges through ion-neutral reactions

    Science.gov (United States)

    Hiraki, Y.; Kasai, Y.; Fukunishi, H.

    2008-07-01

    We estimate the concentration changes, caused by streamer discharge in sprites, of ozone and related minor species as odd nitrogen (NOx) and hydrogen (HOx) families in the upper stratosphere and mesosphere. The streamer has an intense electric field and high electron density at its head, where a large number of chemically-radical ions and atoms are produced through electron impact on neutral molecules. After its propagation, densities of minor species can be perturbed through ion-neutral chemical reactions initiated by the relaxation of these radical products. We evaluate the production rates of ions and atoms using an electron kinetics model and by assuming that the electric field and electron density are in the head region. We calculate the density variations mainly for NOx, Ox, and HOx species using a one-dimensional model of the neutral and ion composition of the middle atmosphere, including the effect of the sprite streamer. Results at the nighttime condition show that the densities of NO, O3, H, and OH increase suddenly through reactions triggered by the first atomic nitrogen and oxygen product, and electrons just after streamer initiation. It is shown that NO and NO2 still remain for 1 h by a certain order of increase with their source-sink balance, predominantly around 60 km; for other species, increases in O3, OH, HO2, and H2O2 still remain in the range of 40 70 km. From this affirmative result of long-time behavior previously not presented, we emphasize that sprites would have the power to impact local chemistry at night. We also discuss the consistency with previous theoretical and observational studies, along with future suggestions.

  20. Li+ alumino-silicate ion source development for the Neutralized Drift Compression Experiment (NDCX)

    International Nuclear Information System (INIS)

    Roy, Prabir K.; Greenway, Wayne G.; Kwan, Joe W.; Seidl, Peter A.; Waldron, William L.; Wu, James K.

    2010-01-01

    We report results on lithium alumino-silicate ion source development in preparation for warm-dense-matter heating experiments on the new Neutralized Drift Compression Experiment (NDCX-II). The practical limit to the current density for a lithium alumino-silicate source is determined by the maximum operating temperature that the ion source can withstand before running into problems of heat transfer, melting of the alumino-silicate material, and emission lifetime. Using small prototype emitters, at a temperature of ∼1275 C, a space-charge-limited Li + beam current density of J ∼1 mA/cm 2 was obtained. The lifetime of the ion source was ∼50 hours while pulsing at a rate of 0.033 Hz with a pulse duration of 5-6 (micro) s.

  1. Li+ alumino-silicate ion source development for the Neutralized Drift Compression Experiment (NDCX)

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Prabir K.; Greenway, Wayne G.; Kwan, Joe W.; Seidl, Peter A.; Waldron, William L.; Wu, James K.

    2010-10-01

    We report results on lithium alumino-silicate ion source development in preparation for warmdense-matter heating experiments on the new Neutralized Drift Compression Experiment (NDCXII). The practical limit to the current density for a lithium alumino-silicate source is determined by the maximum operating temperature that the ion source can withstand before running into problems of heat transfer, melting of the alumino-silicate material, and emission lifetime. Using small prototype emitters, at a temperature of ~;;1275 oC, a space-charge-limited Li+ beam current density of J ~;;1 mA/cm2 was obtained. The lifetime of the ion source was ~;;50 hours while pulsing at a rate of 0.033 Hz with a pulse duration of 5-6 mu s.

  2. Stoichiometric carbon nitride synthesized by ion beam sputtering and post nitrogen ion implantation

    Energy Technology Data Exchange (ETDEWEB)

    Valizadeh, R.; Colligon, J.S. [Salford Univ. (United Kingdom). DMM Institute; Katardiev, I.V. [Uppsala Univ. (Sweden). Angstrom Laboratory; Faunce, C.A.; Donnelly, S.E. [Salford Univ. (United Kingdom). Science Institute

    1998-06-01

    Full text: Carbon nitride films have been deposited on Si (100) by ion beam sputtering a vitreous graphite target with nitrogen and argon ions with and without concurrent N2 ion bombardment at room temperature. The sputtering beam energy was 1000 eV and the assisted beam energy was 300 eV with ion / atom arrival ratio ranging from 0.5 to 5. The carbon nitride films were deposited both as single layer directly on silicon substrate and as multilayer between two layers of stoichiometric amorphous silicon nitride and polycrystalline titanium nitride. The deposited films were implanted ex-situ with 30 keV nitrogen ions with various doses ranging from 1E17 to 4E17 ions.cm{sup -2} and 2 GeV xenon ion with a dose of 1E12 ions.cm{sup -2} . The nitrogen concentration of the films was measured with Rutherford Backscattering (RBS), Secondary Neutral Mass Spectrometry (SNMS) and Parallel Electron Energy Loss Spectroscopy (PEELS). The nitrogen concentration for as deposited sample was 34 at% and stoichiometric carbon nitride C{sub 3}N{sub 4} was achieved by post nitrogen implantation of the multi-layered films. Post bombardment of single layer carbon nitride films lead to reduction in the total nitrogen concentration. Carbon K edge structure obtained from PEELS analysis suggested that the amorphous C{sub 3}N{sub 4} matrix was predominantly sp{sup 2} bonded. This was confirmed by Fourier Transforrn Infra-Red Spectroscopy (FTIR) analysis of the single CN layer which showed the nitrogen was mostly bonded with carbon in nitrile (C{identical_to}N) and imine (C=N) groups. The microstructure of the film was determined by Transmission Electron Microscopy (TEM) which indicated that the films were amorphous.

  3. Design study of primary ion provider for relativistic heavy ion collider electron beam ion source.

    Science.gov (United States)

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

    2010-02-01

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

  4. Time resolved ion beam induced charge collection

    International Nuclear Information System (INIS)

    Sexton W, Frederick; Walsh S, David; Doyle L, Barney; Dodd E, Paul

    2000-01-01

    Under this effort, a new method for studying the single event upset (SEU) in microelectronics has been developed and demonstrated. Called TRIBICC, for Time Resolved Ion Beam Induced Charge Collection, this technique measures the transient charge-collection waveform from a single heavy-ion strike with a -.03db bandwidth of 5 GHz. Bandwidth can be expanded up to 15 GHz (with 5 ps sampling windows) by using an FFT-based off-line waveform renormalization technique developed at Sandia. The theoretical time resolution of the digitized waveform is 24 ps with data re-normalization and 70 ps without re-normalization. To preserve the high bandwidth from IC to the digitizing oscilloscope, individual test structures are assembled in custom high-frequency fixtures. A leading-edge digitized waveform is stored with the corresponding ion beam position at each point in a two-dimensional raster scan. The resulting data cube contains a spatial charge distribution map of up to 4,096 traces of charge (Q) collected as a function of time. These two dimensional traces of Q(t) can cover a period as short as 5 ns with up to 1,024 points per trace. This tool overcomes limitations observed in previous multi-shot techniques due to the displacement damage effects of multiple ion strikes that changed the signal of interest during its measurement. This system is the first demonstration of a single-ion transient measurement capability coupled with spatial mapping of fast transients

  5. Spectrometer for cluster ion beam induced luminescence

    Energy Technology Data Exchange (ETDEWEB)

    Ryuto, H., E-mail: ryuto@kuee.kyoto-u.ac.jp; Sakata, A.; Takeuchi, M.; Takaoka, G. H. [Photonics and Electronics Science and Engineering Center, Kyoto University, Kyoto 615-8510 (Japan); Musumeci, F. [Department of Physics and Astronomy, Catania University, Catania 95123 (Italy); INFN Laboratori Nazionali del Sud, Catania 95123 (Italy)

    2015-02-15

    A spectrometer to detect the ultra-weak luminescence originated by the collision of cluster ions on the surfaces of solid materials was constructed. This spectrometer consists of 11 photomultipliers with band-pass interference filters that can detect the luminescence within the wavelength ranging from 300 to 700 nm and of a photomultiplier without filter. The calibration of the detection system was performed using the photons emitted from a strontium aluminate fluorescent tape and from a high temperature tungsten filament. Preliminary measurements show the ability of this spectrometer to detect the cluster ion beam induced luminescence.

  6. Measurement of ultra-low ion energy of decelerated ion beam using a deflecting electric field

    Energy Technology Data Exchange (ETDEWEB)

    Thopan, P.; Suwannakachorn, D.; Tippawan, U. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, L.D., E-mail: yuld@thep-center.org [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand)

    2015-12-15

    In investigation on ultra-low-energy ion bombardment effect on DNA, an ion beam deceleration lens was developed for high-quality ultra-low-energy ion beam. Measurement of the ion energy after deceleration was necessary to confirm the ion beam really decelerated as theoretically predicted. In contrast to conventional methods, this work used a simple deflecting electrostatic field after the deceleration lens to bend the ion beam. The beam bending distance depended on the ion energy and was described and simulated. A system for the measurement of the ion beam energy was constructed. It consisted of a pair of parallel electrode plates to generate the deflecting electrical field, a copper rod measurement piece to detect ion beam current, a vernier caliper to mark the beam position, a stepping motor to translate the measurement rod, and a webcam-camera to read the beam bending distance. The entire system was installed after the ion-beam deceleration lens inside the large chamber of the bioengineering vertical ion beam line. Moving the measurement rod across the decelerated ion beam enabled to obtain beam profiles, from which the beam bending distance could be known and the ion beam energy could be calculated. The measurement results were in good agreement with theoretical and simulated results.

  7. Integrating supervision, control and data acquisition—The ITER Neutral Beam Test Facility experience

    Energy Technology Data Exchange (ETDEWEB)

    Luchetta, A., E-mail: adriano.luchetta@igi.cnr.it; Manduchi, G.; Taliercio, C.; Breda, M.; Capobianco, R.; Molon, F.; Moressa, M.; Simionato, P.; Zampiva, E.

    2016-11-15

    Highlights: • The paper describes the experience gained in the integration of different systems for the control and data acquisition system of the ITER Neutral Beam Test Facility. • It describes the way the different frameworks have been integrated. • It reports some lessons learnt during system integration. • It reports some authors’ considerations about the development the ITER CODAC. - Abstract: The ITER Neutral Beam (NBI) Test Facility, under construction in Padova, Italy consists in the ITER full scale ion source for the heating neutral beam injector, referred to as SPIDER, and the full size prototype injector, referred to as MITICA. The Control and Data Acquisition System (CODAS) for SPIDER has been developed and is going to be in operation in 2016. The system is composed of four main components: Supervision, Slow Control, Fast Control and Data Acquisition. These components interact with each other to carry out the system operation and, since they represent a common pattern in fusion experiments, software frameworks have been used for each (set of) component. In order to reuse as far as possible the architecture developed for SPIDER, it is important to clearly define the boundaries and the interfaces among the system components so that the implementation of any component can be replaced without affecting the overall architecture. This work reports the experience gained in the development of SPIDER components, highlighting the importance in the definition of generic interfaces among component, showing how the specific solutions have been adapted to such interfaces and suggesting possible approaches for the development of other ITER subsystems.

  8. Production of microbunched beams of very highly charged ions with an electron beam ion source

    International Nuclear Information System (INIS)

    Stoeckli, M.P.

    1998-01-01

    Electron beam ion sources produce very highly charged ions most efficiently in a batch mode as the confinement time can be directly optimized for the production of the desired charge state. If, after confinement, the voltage of the ion-confining downstream dam is lowered rapidly, all ions escape and form an ion beam pulse with a length of a few tens of μs. Raising the main trap voltage while maintaining a constant dam voltage in a open-quotes spill-over expulsionclose quotes reduces the energy spread of the expelled ions. The longer time periods of open-quotes slow-,close quotes open-quotes leaky batch mode-,close quotes and open-quotes direct current (dc) batch mode-close quotes expulsions allow for increasing the ion beam duty cycle. Combining the rapid expulsion with one of the latter methods allows for the expulsion of the ions of a single batch in many small microbunches with variable intervals, maintaining the low energy spread and the increased duty cycle of slow expulsions. Combining the open-quotes microbunchingclose quotes with open-quotes dc batch mode productionclose quotes and a multitrap operation will eventually allow for the production of equally intense ion bunches over a wide range of frequencies without any deadtime, and with minimal compromise on the most efficient production parameters. copyright 1998 American Institute of Physics

  9. Ion beam therapy fundamentals, technology, clinical applications

    CERN Document Server

    2012-01-01

    The book provides a detailed, up-to-date account of the basics, the technology, and the clinical use of ion beams for radiation therapy. Theoretical background, technical components, and patient treatment schemes are delineated by the leading experts that helped to develop this field from a research niche to its current highly sophisticated and powerful clinical treatment level used to the benefit of cancer patients worldwide. Rather than being a side-by-side collection of articles, this book consists of related chapters. It is a common achievement by 76 experts from around the world. Their expertise reflects the diversity of the field with radiation therapy, medical and accelerator physics, radiobiology, computer science, engineering, and health economics. The book addresses a similarly broad audience ranging from professionals that need to know more about this novel treatment modality or consider to enter the field of ion beam therapy as a researcher. However, it is also written for the interested public an...

  10. High-beta experiments with neutral-beam injection on PDX

    International Nuclear Information System (INIS)

    Johnson, D.; Bell, M.; Bitter, M.

    1983-01-01

    Experimental investigations of high-beta plasmas produced in PDX with near-perpendicular neutral-beam injection are reported. Systematic power scans have been performed over a wide range of toroidal fields (νsub(T)q.7 T< Bsub(T)<2.2 T) and plasma currents (200 kA< Isub(p)<500 kA). At high toroidal fields, the change in total stored energy due to beam injection increases linearly with input power and also increases with plasma current. At lower toroidal fields and low injection power levels, the stored energy also increases with power and plasma current. However, at high power and low toroidal fields, a saturation in heating is observed. This result suggests the onset of a νsub(T) limit for circular cross-section tokamaks with near-perpendicular injection. Scaling experiments indicate that this νsub(T) limit increases with rising 1/q. Values of νsub(T)approx.=3% at qsub(PSI)=1.8 have been achieved. At high values of νsub(T)q, short bursts of MHD activity are observed, synchronized with sharply increased fluxes of perpendicular charge-exchange neutrals and rapid decreases in the rate of beam-driven neutron production. When strong bursts occur, there is a significant depletion of the fast-ion population. Estimates of the fast-ion loss indicate that it could explain the observed decrease in heating, although an additional reduction in thermal-plasma confinement cannot be ruled out. Numerical studies using measured pressure profiles predict that the equilibria obtained become unstable to the ideal n=1 internal mode, at about the same value of 0 where the new fluctuations are observed. (author)

  11. Maximum entropy algorithm and its implementation for the neutral beam profile measurement

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Wook; Cho, Gyu Seong [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of); Cho, Yong Sub [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1997-12-31

    A tomography algorithm to maximize the entropy of image using Lagrangian multiplier technique and conjugate gradient method has been designed for the measurement of 2D spatial distribution of intense neutral beams of KSTAR NBI (Korea Superconducting Tokamak Advanced Research Neutral Beam Injector), which is now being designed. A possible detection system was assumed and a numerical simulation has been implemented to test the reconstruction quality of given beam profiles. This algorithm has the good applicability for sparse projection data and thus, can be used for the neutral beam tomography. 8 refs., 3 figs. (Author)

  12. Heavy ion beam excitation of rare gases

    International Nuclear Information System (INIS)

    Ribitzki, G.; Ulrich, A.; Busch, B.; Kroetz, W.; Miller, R.; Wieser, J.

    1991-01-01

    The emission of light from rare gas targets at pressures of more than 100 Pa excited by a pulsed heavy ion beam has been studied. The absolute intensity of several spectral lines has been measured as a function of time at different target gas pressures. Population densities, excitation cross sections, and rate constants for collisional quenching were determined from the line intensities and the lifetimes of the excited states. (orig.)

  13. Calorimetry of ion beam damage in silicon

    International Nuclear Information System (INIS)

    Roorda, S.; Kajrys, G.; Graham, J.

    1994-01-01

    Annealing of ion-beam damage in crystalline Si has been characterized by differential scanning calorimetry and infrared absorption spectroscopy. Si discs of 100 μm thickness have been bombarded with 3.4 MeV protons. Scanning calorimetry reveals a sharp peak riding on a broad background signal. From infrared absorption, this peak is tentatively identified as heat release associated with divacancy annihilation. (orig.)

  14. 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

  15. Modelling third harmonic ion cyclotron acceleration of deuterium beams for JET fusion product studies experiments

    DEFF Research Database (Denmark)

    Schneider, M.; Johnson, T.; Dumont, R.

    2016-01-01

    Recent JET experiments have been dedicated to the studies of fusion reactions between deuterium (D) and Helium-3 (3He) ions using neutral beam injection (NBI) in synergy with third harmonic ion cyclotron radio-frequency heating (ICRH) of the beam. This scenario generates a fast ion deuterium tail...... enhancing DD and D3He fusion reactions. Modelling and measuring the fast deuterium tail accurately is essential for quantifying the fusion products. This paper presents the modelling of the D distribution function resulting from the NBI+ICRF heating scheme, reinforced by a comparison with dedicated JET fast...

  16. Design and implementation of a user-friendly interface for DIII-D neutral beam automated operation

    International Nuclear Information System (INIS)

    Phillips, J.; Colleraine, A.P.; Hong, R.; Kim, J.; Lee, R.L.; Wight, J.J.

    1989-12-01

    The operational interface to the DIII-D neutral beam system, in use for the past 10 years, consisted of several interactive devices that the operator used to sequence neutral beam conditioning and plasma heating shots. Each of four independent MODCOMP Classic control computers (for four DIII-D beamlines) included a touch screen, rotary knobs, an interactive dual port terminal, and a keyboard to selectively address each of five display screens. Most of the hardware had become obsolete and repair was becoming increasingly expensive. It was clear that the hardware could be replaced with current equipment, while improving the ergonomics of control. Combined with an ongoing effort to increase the degree of automated operation and its reliability, a single microcomputer-based interface for each of the four neutral beam MODCOMP Classic control computers was developed, effectively replacing some twenty pieces of hardware. Macintosh II microcomputers were selected, with 1 megabyte of RAM and ''off-the-shelf'' input/output (I/O) consisting of a mouse, serial ports, and two monochrome high-resolution video monitors. The software is written in PASCAL and adopts standard Macintosh ''window'' techniques. From the Macintosh interface to the MODCOMP Classic, the operator can control the power supply setpoints, adjust ion source timing and synchronization, call up waveform displays on the Grinnell color display system, view the sequencing of procedures to ready a neutral beam shot, and add operator comments to an automated shot logging system. 3 refs., 2 figs

  17. Effects of ambient gas in beam drift space on performance of high brightness and low energy ion beam

    International Nuclear Information System (INIS)

    Yoshikawa, T.; Nakamura, S.; Ueda, Y.; Nishikawa, M.; Goto, S.

    1995-01-01

    Effects of the ambient gas in the ion drift space on the transport property of the low energy (155 eV) and high brightness beam are studied experimentally. A bucket ion source with single-aperture triode extraction is used. Beam characteristics such as the divergence angle and the current density are improved by the increase in the ambient gas pressure in the high brightness beam (high deceleration voltage, -2000 V), but not in the low brightness beam (low deceleration voltage, -600 V). The beam spreading due to the space charge of the ion beam is seen at the low ambient gas pressure when the central current density, which is measured at 35 cm downstream side from the electrode system, exceeds 5 μA/cm 2 . The electron density in the ion-beam plasma increases with the ambient gas pressure, but the space charge is not sufficiently neutralized by the electrons produced by the ambient gas atom ionization. copyright 1995 American Institute of Physics

  18. Laboratory of ion beam applications at ATOMKI

    International Nuclear Information System (INIS)

    Borbely-Kiss, I.; Huszank, R.; Kertesz, Zs.; Kiss, A.Z.; Koltay, E.; Rajta, I.; Simon, A.; Szabo, Gy.; Szikszai, Z.; Szilasi, S.Z.; Szoboszlai, Z.; Uzonyi, I.

    2008-01-01

    Introduction. The Laboratory of Ion Beam Applications of ATOMKI is devoted to applications of atomic and nuclear physics in the fields of environmental research, biomedicine, geology, materials and surface science (including ion beam induced damage investigations and proton beam lithography) and cultural heritage research. We perform our work in the frame of various projects and collaborations: EU, IAEA, R and D, OTKA, etc. Our laboratory provides service for external (national and international) and internal users and contributes to higher education, as well. The Laboratory is based on the home-made 5 MV Van de Graaff (VdG) electrostatic accelerator of the institute. The accelerator was put into operation in 1971 and in the beginning it supplied ion beams exclusively for nuclear physics. A few years later with the measurements of K-shell ionization cross sections the door became open also for basic atomic physics. In parallel with this basic study, the application of proton induced X-ray emission (PIXE) for the elemental analysis of biological (hair, erythrocyte and blood plasma) samples and atmospheric aerosols also started. The first paper on PIXE, a methodological one, was published in 1978. The experience gained on these applications and later on archaeology led to the construction of complex PIXE chambers, which were sold, together with the corresponding know-how, to institutions in China, Portugal, Bangladesh, Jordan, North Korea, Singapore, Cuba and Mexico through the International Atomic Energy Agency (IAEA). For the evaluation of PIXE spectra the laboratory has been continuously developing its own computer programme package. The first version of this continuous development was published in 1988. In the meantime a second IBA analysis method, the proton induced gamma ray emission (PIGE), was introduced in the laboratory and was applied simultaneously with PIXE. Application of deuteron induced gamma ray emission (DIGE) started more than a decade later. A

  19. Transport of ion beams by magnetic fields on the beam edges

    International Nuclear Information System (INIS)

    Hooper, E.B.

    1975-01-01

    The transport of low energy ion beams (less than 10 keV) by magnetic fields on the edge of the beam is analyzed. Calculations indicate that beams with low transverse temperature can be transported. (U.S.)

  20. Mutation induction of orchids by ion beams

    International Nuclear Information System (INIS)

    Affrida Abu Hassan; Zaiton Ahmad; Sakinah Ariffin; Oono, Yutaka; Hase, Yoshihiro; Shikazono; Naoya; Narumi, Issay; Tanaka, Atsushi

    2010-01-01

    Mutation induction using ionizing radiation provides an effective alternative means for improvement of orchids. In this study, ion beams were used because they have much higher linear energy transfer (LET) than X-rays or gamma rays, and subsequently lead to higher mutation frequency and broad mutation spectrum. The proto corm-like bodies (PLBs) of three orchid species (Dendrobium crumenatum, Dendrobium mirbellianum) were irradiated at various doses with 320 MeV 12 C 6+ ions accelerated by Azimuthally Varying Field (AVF) cyclotron at JAEAs Takasaki Ion Accelerators for Advanced Radiation Application (TIARA). The optimum irradiation condition and the effect of irradiation on each species were studied, particularly on flower colour and morphology, flowering habit and insect resistance. Dose effects on plantlet regeneration for each species were also obtained. Some morphological changes were observed in flowers of Dendrobium crumenatum, whilst one insect resistant mutant was obtained in Dendrobium mirbellianum. (author)

  1. Application of the code Slac to the study of Ion Extraction Systems in Neutral Injectors

    International Nuclear Information System (INIS)

    Garcia, M.; Liniers, M.; Guasp, J.

    1997-01-01

    In this study different extraction geometries for intense ion beams have been analyzed with the code SLAC, in view of its possible application to the neutral injectors of TJ-II. With this aim, we have introduced several modifications in the code in order to correctly simulate the transition between the ion source plasma and the extraction region, which has great impact on the beam optics. These modifications include the introduction of a population of Boltzmann electrons in the transition region, and the implementation of an option to simulate the thermal velocity of the ions in the source. We have found a better agreement between the results obtained with the new version of the code and the experimental data in two well known systems. With this new version of the code two different studies have been carried out: in the first place an optimization of the ATF injectors extraction system for its use on TJ-II, leading to an optimum value of the gap in the energy range 30-40 KeV, and in the second place a systematic study of extraction geometries at 40 KeV. As a result of this second study we have found the combinations of parameters that can be used under different working conditions (e.g. different pulse lengths), leading to acceptable values of the beam divergence. (Author)

  2. High-power ICRF and ICRF plus neutral-beam heating on PLT

    International Nuclear Information System (INIS)

    Hwang, D.; Bitter, M.; Budny, R.

    1983-01-01

    PLT ICRF experiments with RF powers up to approx.=3 MW have demonstrated efficient plasma heating in both the minority fundamental and the second harmonic ion-cyclotron regimes. In the minority 3 He regime, ion temperatures of approx.=3 keV have been produced along with approx.=1 kW of D- 3 He fusion power and substantial electron heating. In the second harmonic H regime, an equivalent averaged ion energy of approx.=4 keV has been achieved. Combined ICRF plus neutral-beam heating experiments with auxiliary powers totalling up to 4.5 MW have provided insight into auxiliary heating performance at stored plasma energy levels up to approx.=100 kJ. Values of #betta#sub(phi) in the range of 1.5-2% have been attained for Bsub(phi) approx.=17 kG. Energetic discharges with n-barsub(e) up to approx.6x10 13 cm - 3 at Bsub(phi) approx.=28 kG have also been investigated. Preliminary confinement studies suggest that energetic ion losses may contribute to a direct loss of the input RF power in the H minority heating regime but are insignificant in the 3 He minority case. The energy confinement time for the H minority regime is reduced somewhat from the Ohmic value. (author)

  3. Neutralization and equilibration of highly charged argon ions at grazing incidence on a graphite surface

    International Nuclear Information System (INIS)

    Winecki, S.; Cocke, C.L.; Stoeckli, M.P.; Fry, D.

    1996-01-01

    Final charge state distributions of argon ions, scattered grazingly from a smooth highly oriented pyrolytic graphite (HOPG) surface, have been measured as a function of initial charge state (q=4-17) and impact velocity (v=0.15-0.62 a.u.). The final charge state distribution changes strongly with the impact velocity, but is almost independent of the initial charge state. The neutralization during grazing-angle scattering is compared to the charge state equilibration experienced by ions passing through a solid (carbon foil), and these two processes seem to have common properties. A K x-ray spectrum from the K-shell vacancy decay of 51 keV Ar 17+ projectiles was obtained as a function of the angle between the ion beam and the surface. First measurements of x-ray spectra in coincidence with grazingly scattered ions are reported. A simple model for argon neutralization near and below the surface is proposed. The model assumes a direct side-feeding into the Ar M-shell followed by Auger and radiative L and K-shell filling

  4. Nonlinear plasma waves excitation by intense ion beams in background plasma

    International Nuclear Information System (INIS)

    Kaganovich, Igor D.; Startsev, Edward A.; Davidson, Ronald C.

    2004-01-01

    Plasma neutralization of an intense ion pulse is of interest for many applications, including plasma lenses, heavy ion fusion, cosmic ray propagation, etc. An analytical electron fluid model has been developed to describe the plasma response to a propagating ion beam. The model predicts very good charge neutralization during quasi-steady-state propagation, provided the beam pulse duration τ b is much longer than the electron plasma period 2π/ω p , where ω p =(4πe 2 n p /m) 1/2 is the electron plasma frequency, and n p is the background plasma density. In the opposite limit, the beam pulse excites large-amplitude plasma waves. If the beam density is larger than the background plasma density, the plasma waves break. Theoretical predictions are compared with the results of calculations utilizing a particle-in-cell (PIC) code. The cold electron fluid results agree well with the PIC simulations for ion beam propagation through a background plasma. The reduced fluid description derived in this paper can provide an important benchmark for numerical codes and yield scaling relations for different beam and plasma parameters. The visualization of numerical simulation data shows complex collective phenomena during beam entry and exit from the plasma

  5. Production of intense metallic ion beams in order of isotopic separations

    International Nuclear Information System (INIS)

    Sarrouy, J.L.

    1955-01-01

    We describe an isotope separator with magnetic sector of 60 deg that permits, with a process of neutralization of the space charge, to use efficiently intense ion beams. The sources of realized ions provide ionic debits of 10 mA. This present work deals who to obtain intense ion beams (10 to 15 mA), different processes of ion currents measurement, as well as the study of the phenomenon of space charge neutralization. The second part of this memory will be on the survey and the adaptation on the source of various type of oven permitting to spray and to ionize metals directly. By order of increasing difficulty of vaporization, we reached the chromium. (M.B.) [fr

  6. Development of ion/proton beam equipment for industrial uses

    International Nuclear Information System (INIS)

    Choi, Byung Ho; Lee, J. H.; Cho, Y. S.; Joo, P. K.; Kang, S. S.; Song, W. S.; Kim, H. J.; Lee, J. H.; Chang, G. H.; Bang, S. W.

    1999-12-01

    KAERI has possessed design and fabrication technologies of various ion sources including Duoplasmatron and DuoPiGatron developed by R and D projects of the long-term nuclear technology development program. In order to industrialize ion beam equipments utilizing these ion sources, a technology transfer project for a technology transfer project for a domestic firm has been performed. Under this project, engineers of the firm have been trained through classroom lectures of ion beam principles and OJT, an ion/proton beam equipment (DEMO equipment) has been designed, assembled and commissioned jointly with the engineers. Quality of the ion sources has been quantified, and technologies for ion beam equipment construction, functional test and application research have been developed. The DEMO equipment, which consists of an ion source, power supplies, vacuum, cooling and target systems, has been fabricated and tested to secure stability and reliability for industrial uses. Various characteristic tests including high voltage insulation, beam extraction, beam current measuring, etc. have been performed. This DEMO can be utilized for ion sources development as well as ion beam process development for various industrial products. Engineers of the firm have been trained for the industrialization of ion beam equipment and joined in beam application technology development to create industrial needs of beam equipment. (author)

  7. Thermo-mechanical analysis of an acceleration grid for the international thermonuclear experimental reactor-neutral beam injection system

    International Nuclear Information System (INIS)

    Fujiwara, Yukio; Hanada, Masaya; Okumura, Yoshikazu; Suzuki, Satoshi; Watanabe, Kazuhiro

    2001-01-01

    In the engineering design of a negative-ion beam source for a high-power neutral beam injection (NBI) system, one of the most important issues is thermo-mechanical design of acceleration grids for producing several tens of MW ion beams. An acceleration grid for the international thermonuclear experimental reactor-neutral beam injection (ITER-NBI) system will be subjected to the heat loading as high as 1.5 MW. In the present paper, thermo-mechanical characteristics of the acceleration grid for the ITER-NBI system were analyzed. Numerical simulation indicated that maximum aperture-axis displacement of the acceleration grid due to thermal expansion would be about 0.7 mm for the heat loading of 1.5 MW. From the thin lens theory of beam optics, beamlet deflection angle by the aperture-axis displacement was estimated to be about 2 mrad, which is within the requirement of the engineering design of the ITER-NBI system. Numerical simulation also indicated that no melting on the acceleration grid would occur for a heat loading of 1.5 MW, while local plastic deformation would happen. To avoid the plastic deformation, it is necessary to reduce the heat loading onto the acceleration grid to less than 1 MW

  8. Ion-neutral Coupling During Deep Solar Minimum

    Science.gov (United States)

    Huang, Cheryl Y.; Roddy, Patrick A.; Sutton, Eric K.; Stoneback, Russell; Pfaff, Robert F.; Gentile, Louise C.; Delay, Susan H.

    2013-01-01

    The equatorial ionosphere under conditions of deep solar minimum exhibits structuring due to tidal forces. Data from instruments carried by the Communication Navigation Outage Forecasting System (CNOFS) which was launched in April 2008 have been analyzed for the first 2 years following launch. The Planar Langmuir Probe (PLP), Ion Velocity Meter (IVM) and Vector Electric Field Investigation (VEFI) all detect periodic structures during the 20082010 period which appear to be tides. However when the tidal features detected by these instruments are compared, there are distinctive and significant differences between the observations. Tides in neutral densities measured by the Gravity Recovery and Climate Experiment (GRACE) satellite were also observed during June 2008. In addition, Broad Plasma Decreases (BPDs) appear as a deep absolute minimum in the plasma and neutral density tidal pattern. These are co-located with regions of large downward-directed ion meridional velocities and minima in the zonal drifts, all on the nightside. The region in which BPDs occur coincides with a peak in occurrence rate of dawn depletions in plasma density observed on the Defense Meterological Satellite Program (DMSP) spacecraft, as well as a minimum in radiance detected by UV imagers on the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) and IMAGE satellites

  9. Consideration of neutral beam prompt loss in the design of a tokamak helicon antenna

    International Nuclear Information System (INIS)

    Pace, D.C.; Van Zeeland, M.A.; Fishler, B.; Murphy, C.

    2016-01-01

    Highlights: • Neutral beam prompt losses place appreciable power on an in-vessel tokamak antenna. • Simulations predict prompt loss power and inform protective tile design. • Experiments confirm the validity of the prompt loss simulations. - Abstract: Neutral beam prompt losses (injected neutrals that ionize such that their first poloidal transit intersects with the wall) can put appreciable power on the outer wall of tokamaks, and this power may damage the wall or other internal components. These prompt losses are simulated including a protruding helicon antenna installation in the DIII-D tokamak and it is determined that 160 kW of power will impact the antenna during the injection of a particular neutral beam. Protective graphite tiles are designed in response to this modeling and the wall shape of the installed antenna is precisely measured to improve the accuracy of these calculations. Initial experiments confirm that the antenna component temperature increases according to the amount of neutral beam energy injected into the plasma. In this case, only injection of beams that are aimed counter to the plasma current produce an appreciable power load on the outer wall, suggesting that the effect is of little concern for tokamaks featuring only co-current neutral beam injection. Incorporating neutral beam prompt loss considerations into the design of this in-vessel component serves to ensure that adequate protection or cooling is provided.

  10. An Absolute Valve for the ITER Neutral Beam Injector

    International Nuclear Information System (INIS)

    Jones, Ch.; Chuilon, B.; Michael, W.

    2006-01-01

    In the ITER reference design a fast shutter was included to limit tritium migration into the beamline vacuum enclosures. The need was recently identified to extend the functionality of the fast shutter to that of an absolute valve in order to facilitate injector maintenance procedures and to satisfy safety requirements in case of an in-vessel loss of coolant event. Three concepts have been examined satisfying the ITER requirements for speed of actuation, sealing performance over the required lifetime, and pressure differential in fault scenarios, namely: a rectangular closure section; a circular cross section; and a rotary JET-type valve. The rectangular section represents the most efficient usage of the available space envelope and leads to a minimum-mass system, although it requires greater total force for a given load per unit length of seal. However, a metallic seal of the '' hard/hard '' type, where the seal relies on the elastic properties of the material and does not utilise any type of spring device, can provide the required seal performance with typical loading of 200 kg/cm. The conceptual design of the proposed absolute valve will be presented. The aperture dimensions are 1.45 m high by 0.6 m wide, with minimum achievable leak rate of 1 · 10 -9 mbarl/s and maximum pressure differential of 3 bar across the valve. Sealing force is provided using two seal plates, linked by a 3 mm thick ' omega ' diaphragm, by pressurisation of the interspace to 8 bar; this allows for a relative movement of the plates of 2 mm. Movement of the device perpendicular to the beam direction is carried out using a novel magnetic drive in order to transmit the motive force across the vacuum boundary, similar to that demonstrated on a test-rig in an earlier study. The conceptual design includes provision of all the services such as pneumatics and water cooling to cope with the heat loads from neutral beams in quasi steady-state operation and from the ITER plasma. A future programme

  11. Focused ion beam milling of carbon fibres

    International Nuclear Information System (INIS)

    Huson, Mickey G.; Church, Jeffrey S.; Hillbrick, Linda K.; Woodhead, Andrea L.; Sridhar, Manoj; Van De Meene, Allison M.L.

    2015-01-01

    A focused ion beam has been used to mill both individual carbon fibres as well as fibres in an epoxy composite, with a view to preparing flat surfaces for nano-indentation. The milled surfaces have been assessed for damage using scanning probe microscopy nano-indentation and Raman micro-probe analysis, revealing that FIB milling damages the carbon fibre surface and covers surrounding areas with debris of disordered carbon. The debris is detected as far as 100 μm from the milling site. The energy of milling as well as the orientation of the beam was varied and shown to have an effect when assessed by Raman spectroscopy. - Highlights: • Focused ion beam (FIB) milling was used to mill flat surfaces on carbon fibres. • Raman spectroscopy showed amorphous carbon was generated during FIB milling. • The amorphous debris is detected as far as 100 μm from the milling site. • This surface degradation was confirmed by nano-indentation experiments.

  12. Progress in the realization of the PRIMA neutral beam test facility

    Science.gov (United States)

    Toigo, V.; Boilson, D.; Bonicelli, T.; Piovan, R.; Hanada, M.; Chakraborty, A.; Agarici, G.; Antoni, V.; Baruah, U.; Bigi, M.; Chitarin, G.; Dal Bello, S.; Decamps, H.; Graceffa, J.; Kashiwagi, M.; Hemsworth, R.; Luchetta, A.; Marcuzzi, D.; Masiello, A.; Paolucci, F.; Pasqualotto, R.; Patel, H.; Pomaro, N.; Rotti, C.; Serianni, G.; Simon, M.; Singh, M.; Singh, N. P.; Svensson, L.; Tobari, H.; Watanabe, K.; Zaccaria, P.; Agostinetti, P.; Agostini, M.; Andreani, R.; Aprile, D.; Bandyopadhyay, M.; Barbisan, M.; Battistella, M.; Bettini, P.; Blatchford, P.; Boldrin, M.; Bonomo, F.; Bragulat, E.; Brombin, M.; Cavenago, M.; Chuilon, B.; Coniglio, A.; Croci, G.; Dalla Palma, M.; D'Arienzo, M.; Dave, R.; De Esch, H. P. L.; De Lorenzi, A.; De Muri, M.; Delogu, R.; Dhola, H.; Fantz, U.; Fellin, F.; Fellin, L.; Ferro, A.; Fiorentin, A.; Fonnesu, N.; Franzen, P.; Fröschle, M.; Gaio, E.; Gambetta, G.; Gomez, G.; Gnesotto, F.; Gorini, G.; Grando, L.; Gupta, V.; Gutierrez, D.; Hanke, S.; Hardie, C.; Heinemann, B.; Kojima, A.; Kraus, W.; Maeshima, T.; Maistrello, A.; Manduchi, G.; Marconato, N.; Mico, G.; Moreno, J. F.; Moresco, M.; Muraro, A.; Muvvala, V.; Nocentini, R.; Ocello, E.; Ochoa, S.; Parmar, D.; Patel, A.; Pavei, M.; Peruzzo, S.; Pilan, N.; Pilard, V.; Recchia, M.; Riedl, R.; Rizzolo, A.; Roopesh, G.; Rostagni, G.; Sandri, S.; Sartori, E.; Sonato, P.; Sottocornola, A.; Spagnolo, S.; Spolaore, M.; Taliercio, C.; Tardocchi, M.; Thakkar, A.; Umeda, N.; Valente, M.; Veltri, P.; Yadav, A.; Yamanaka, H.; Zamengo, A.; Zaniol, B.; Zanotto, L.; Zaupa, M.

    2015-08-01

    The ITER project requires additional heating by two neutral beam injectors, each accelerating to 1 MV a 40 A beam of negative deuterium ions, to deliver to the plasma a power of about 17 MW for one hour. As these requirements have never been experimentally met, it was recognized as necessary to setup a test facility, PRIMA (Padova Research on ITER Megavolt Accelerator), in Italy, including a full-size negative ion source, SPIDER, and a prototype of the whole ITER injector, MITICA, aiming to develop the heating injectors to be installed in ITER. This realization is made with the main contribution of the European Union, through the Joint Undertaking for ITER (F4E), the ITER Organization and Consorzio RFX which hosts the Test Facility. The Japanese and the Indian ITER Domestic Agencies (JADA and INDA) participate in the PRIMA enterprise; European laboratories, such as IPP-Garching, KIT-Karlsruhe, CCFE-Culham, CEA-Cadarache and others are also cooperating. Presently, the assembly of SPIDER is on-going and the MITICA design is being completed. The paper gives a general overview of the test facility and of the status of development of the MITICA and SPIDER main components at this important stage of the overall development; then it focuses on the latest and most critical issues, regarding both physics and technology, describing the identified solutions.

  13. Ion beam induces nitridation of silicon

    International Nuclear Information System (INIS)

    Petravic, M.; Williams, J.S.; Conway, M.

    1998-01-01

    High dose ion bombardment of silicon with reactive species, such as oxygen and nitrogen, has attracted considerable interest due to possible applications of beam-induced chemical compounds with silicon. For example, high energy oxygen bombardment of Si is now routinely used to form buried oxide layers for device purposes, the so called SIMOX structures. On the other hand, Si nitrides, formed by low energy ( 100 keV) nitrogen beam bombardment of Si, are attractive as oxidation barriers or gate insulators, primarily due to the low diffusivity of many species in Si nitrides. However, little data exists on silicon nitride formation during bombardment and its angle dependence, in particular for N 2 + bombardment in the 10 keV range, which is of interest for analytical techniques such as SIMS. In SIMS, low energy oxygen ions are more commonly used as bombarding species, as oxygen provides stable ion yields and enhances the positive secondary ion yield. Therefore, a large body of data can be found in the literature on oxide formation during low energy oxygen bombardment. Nitrogen bombardment of Si may cause similar effects to oxygen bombardment, as nitrogen and oxygen have similar masses and ranges in Si, show similar sputtering effects and both have the ability to form chemical compounds with Si. In this work we explore this possibility in some detail. We compare oxide and nitride formation during oxygen and nitrogen ion bombardment of Si under similar conditions. Despite the expected similar behaviour, some large differences in compound formation were found. These differences are explained in terms of different atomic diffusivities in oxides and nitrides, film structural differences and thermodynamic properties. (author)

  14. Beam loss mechanisms in relativistic heavy-ion colliders

    CERN Document Server

    Bruce, Roderik; Gilardoni, S; Wallén, E

    2009-01-01

    The Large Hadron Collider (LHC), the largest particle accelerator ever built, is presently under commissioning at the European Organization for Nuclear Research (CERN). It will collide beams of protons, and later Pb82+ ions, at ultrarelativistic energies. Because of its unprecedented energy, the operation of the LHC with heavy ions will present beam physics challenges not encountered in previous colliders. Beam loss processes that are harmless in the presently largest operational heavy-ion collider, the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory, risk to cause quenches of superconducting magnets in the LHC. Interactions between colliding beams of ultrarelativistic heavy ions, or between beam ions and collimators, give rise to nuclear fragmentation. The resulting isotopes could have a charge-to-mass ratio different from the main beam and therefore follow dispersive orbits until they are lost. Depending on the machine conditions and the ion species, these losses could occur in loca...

  15. Performance with lead ions of the LHC beam dump system

    CERN Document Server

    Bruce, R; Jensen, L; Lefèvre, T; Weterings, W

    2007-01-01

    The LHC beam dump system must function safely with 208Pb82+ions. The differences with respect to the LHC proton beams are briefly recalled, and the possible areas for performance concerns discussed, in particular the various beam intercepting devices and the beam instrumentation. Energy deposition simulation results for the most critical elements are presented, and the conclusions drawn for the lead ion operation. The expected performance of the beam instrumentation systems are reviewed in the context of the damage potential of the ion beam and the required functionality of the various safety and post-operational analysis requirements.

  16. Recent radioactive ion beam program at RIKEN and related topics

    Indian Academy of Sciences (India)

    525–533. Recent radioactive ion beam program at RIKEN and related topics. AKIRA OZAWA. RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan. Abstract. Recent experimental programs at RIKEN concerning RI beams are reviewed. RIKEN has the ring cyclotron (RRC) with high intense heavy-ion beams and large ...

  17. Radioactive ion beams for solid state research

    CERN Document Server

    Correia, J G

    1996-01-01

    Radioactive isotopes are widely used in many research fields. In some applications they are used as tracers after diffusion or after activation in the material itself through nuclear reactions. For research in solid state physics, the ion implantation technique is the most flexible and convenient method to introduce the radioactive isotopes in the materials to be studied, since it allows the control of the ion dose, the implantation depth and the isotopic purity. The on-line coupling of isotope separators to particle accelerators, as is the case of the ISOLDE facility at CERN, allows the obtention of a wide range of high purity short lived isotopes. Currently, the most stringent limitation for some applications is the low acceleration energy of 60 keV of the ISOLDE beam. In this communication a short review of the current applications of the radioactive beams for research in solid state physics at ISOLDE is done. The development of a post-accelerator facility for MeV radioactive ions is introduced and the adv...

  18. Wien filter for cooled low-energy radioactive ion beams

    NARCIS (Netherlands)

    Nummela, S; Dendooven, P; Heikkinen, P; Huikari, J; Nieminen, A; Jokinen, A; Rinta-Antila, S; Rubchenya, V.; Aysto, J

    2002-01-01

    A Wien filter for cooled radioactive ion beams has been designed at Ion Guide Isotope Separator On Line technique (IGISOL). The purpose of such device is to eliminate doubly charged ions from the mass separated singly charged ions, based on q = +2-->q = +1 charge exchange process in an ion cooler,

  19. Sustaining neutral beam power supply system for the Mirror Fusion Test Facility

    International Nuclear Information System (INIS)

    Eckard, R.D.; Van Ness, H.W.

    1979-01-01

    A fixed-price procurement contract for $24.9 million was awarded to Aydin Energy Division, Palo Alto, CA, for the design, manufacture, installation, and acceptance testing of the sustaining neutral beam power supply system (SNBPSS). This system is scheduled for completion in early 1981 and will provide the conditioned power for the 24 neutral beam source modules. Each of the 24 power supply sets will provide the accel potential of 80 kV at 88 A, the arc power, the filament power, and the suppressor power for its associated neutral beam source module

  20. Progress in control and data acquisition for the ITER neutral beam test facility

    Energy Technology Data Exchange (ETDEWEB)

    Luchetta, Adriano, E-mail: adriano.luchetta@igi.cnr.it [Consorzio RFX, Euratom-ENEA Association, Padova (Italy); Manduchi, Gabriele; Taliercio, Cesare; Soppelsa, Anton [Consorzio RFX, Euratom-ENEA Association, Padova (Italy); Paolucci, Francesco; Sartori, Filippo [Fusion for Energy, Barcelona (Spain); Barbato, Paolo; Capobianco, Roberto; Breda, Mauro; Molon, Federico; Moressa, Modesto; Polato, Sandro; Simionato, Paola; Zampiva, Enrico [Consorzio RFX, Euratom-ENEA Association, Padova (Italy)

    2013-10-15

    Highlights: ► An ion source experiment, referred to as SPIDER, is under construction in the ITER neutral beam test facility. ► The progress in designing and testing the SPIDER control and data acquisition system is reported. ► An original approach is proposed in using ITER CODAC and non-ITER CODAC technology. -- Abstract: SPIDER, the ion source test bed in the ITER neutral beam test facility, is under construction and its operation is expected to start in 2014. Control and data acquisition for SPIDER are undergoing final design. SPIDER CODAS, as the control and data acquisition system is referred to, is requested to manage 25 plant units, to acquire 1000 analogue signals with sampling rates ranging from a few S/s to 10 MS/s, to acquire images with up to 100 frames per second, to operate with long pulses lasting up to 1 h, and to sustain 200 MB/s data throughput into the data archive with an annual data storage amount of up to 50 TB. SPIDER CODAS software architecture integrates three open-source software frameworks each addressing specific system requirements. Slow control exploits the synergy among EPICS and Siemens S7 programmable controllers. Data handling is by MDSplus a data-centric framework that is geared towards the collection and organization of scientific data. Diagnostics based on imaging drive the design of data throughput and archive size. Fast control is implemented by using MARTe, a data-driven, object-oriented, real-time environment. The paper will describe in detail the progress of the system hardware and software architecture and will show how the software frameworks interact to provide the functions requested by SPIDER CODAS. The paper will focus on how the performance requirements can be met with the described SPIDER CODAS architecture, describing the progress achieved by carrying out prototyping activities.

  1. CINEMA (Cubesat for Ion, Neutral, Electron, MAgnetic fields)

    Science.gov (United States)

    Lin, R. P.; Parks, G. K.; Halekas, J. S.; Larson, D. E.; Eastwood, J. P.; Wang, L.; Sample, J. G.; Horbury, T. S.; Roelof, E. C.; Lee, D.; Seon, J.; Hines, J.; Vo, H.; Tindall, C.; Ho, J.; Lee, J.; Kim, K.

    2009-12-01

    The NSF-funded CINEMA mission will provide cutting-edge magnetospheric science and critical space weather measurements, including high sensitivity mapping and high cadence movies of ring current, >4 keV Energetic Neutral Atom (ENA), as well as in situ measurements of suprathermal electrons (>~2 keV) and ions (>~ 4 keV) in the auroral and ring current precipitation regions, all with ~1 keV FWHM resolution and uniform response up to ~100 keV. A Suprathermal Electron, Ion, Neutral (STEIN) instrument adds an electrostatic deflection system to the STEREO STE (SupraThermal Electron) 4-pixel silicon semiconductor sensor to separate ions from electrons and from ENAs up to ~20 keV. In addition, inboard and outboard (on an extendable 1m boom) magnetoresistive sensor magnetometers will provide high cadence 3-axis magnetic field measurements. A new attitude control system (ACS) uses torque coils, a solar aspect sensor and the magnetometers to de-tumble the 3u CINEMA spacecraft, then spin it up to ~1 rpm with the spin axis perpendicular to the ecliptic, so STEIN can sweep across most of the sky every minute. Ideally, CINEMA will be placed into a high inclination low earth orbit that crosses the auroral zone and cusp. An S-band transmitter will be used to provide > ~8 kbps orbit-average data downlink to the ~11m diameter antenna of the Berkeley Ground Station. Two more identical CINEMA spacecraft will be built by Kyung Hee University (KHU) in Korea under their World Class University (WCU) program, to provide stereo ENA imaging and multi-point in situ measurements. Furthermore, CINEMA’s development of miniature particle and magnetic field sensors, and cubesat-size spinning spacecraft will be important for future nanosatellite space missions.

  2. High Precision, Sensitive, Near-IR Spectroscopy in a Fast Ion Beam

    Science.gov (United States)

    Porambo, Michael; Kreckel, Holger; Mills, Andrew; Perera, Manori; Siller, Brian; McCall, Benjamin J.

    2011-10-01

    In the low temperatures and pressures of the interstellar medium (ISM), molecular ions play key roles as reactants and intermediates, as well as physical probes of the interstellar environment. As such, high resolution laboratory spectra of these ions aid in further understanding the chemistry and physics of the ISM. There are many challenges to high resolution molecular ion spectroscopy in the laboratory, though. To combat these challenges, we have built a fast ion beam spectrometer that possesses rigorous ion-neutral discrimination, high sensitivity and resolution, and mass identification capabilities. The primary components of the system are a cold cathode ion source, an electrostatic ion optical system for steering and focusing the extracted ion beam, an ion beam-laser overlap region where the spectroscopy takes place, and a time-of-flight mass spectrometer for mass studies of the ion beam. The spectra are obtained using a highly sensitive spectroscopic technique called Noise Immune Cavity Enhanced Optical Heterodyne Molecular Spectroscopy (NICE-OHMS). By calibrating the spectra with an optical frequency comb, line centers of transitions can be determined to future, a supersonic expansion discharge source will take the place of the current cold cathode in order to create an ion beam with much lower rotational temperature. We have recorded near-infrared rovibronic transitions of the 1-0 Meinel band of N2+as a proof of concept of this setup. In addition to analyzing the lineshapes of the transitions, the line center of the Q22(14.5) line was determined to an accuracy of ~8 MHz. Presently, we are working to extend our ion beam spectroscopy to the study of mid-infrared vibrational transitions of other molecular ions using a Difference Frequency Generation (DFG) laser tunable from 2.8 to 4.8 μm.

  3. A radioactive ion beam facility using photofission

    CERN Document Server

    Diamond, W T

    1999-01-01

    Use of a high-power electron linac as the driver accelerator for a Radioactive Ion Beam (RIB) facility is proposed. An electron beam of 30 MeV and 100 kW can produce nearly 5x10 sup 1 sup 3 fissions/s from an optimized sup 2 sup 3 sup 5 U target and about 60% of this from a natural uranium target. An electron beam can be readily transmitted through a thin window at the exit of the accelerator vacuum system and transported a short distance through air to a water-cooled Bremsstrahlung-production target. The Bremsstrahlung radiation can, in turn, be transported through air to the isotope-production target. This separates the accelerator vacuum system, the Bremsstrahlung target and the isotope-production target, reducing remote handling problems. The electron beam can be scanned over a large target area to reduce the power density on both the Bremsstrahlung and isotope-production targets. These features address one of the most pressing technological challenges of a high-power RIB facility, namely the production o...

  4. The internal kink mode in an anisotropic flowing plasma with application to modeling neutral beam injected sawtoothing discharges

    Science.gov (United States)

    Graves, J. P.; Sauter, O.; Gorelenkov, N. N.

    2003-04-01

    For some time it has not been clear to what extent neutral injected beam ions have a stabilizing influence on sawteeth. To investigate this, the well known toroidal internal kink instability is generalized to account for weakly anisotropic and flowing equilibria. An analytical approach is proposed, which upon employing an appropriate model distribution function, accurately accounts for the hot ion response of neutral beam injection (NBI) to the internal kink mode. Large fluid contributions, which are expected to arise as a consequence of the anisotropic velocity deposition of NBI, are identified and shown to be stabilizing to the internal kink mode for populations with large passing fractions. In particular for tangential injection, such as that employed in the Joint European Torus [J. Wesson, Tokamaks, 2nd ed. (Oxford Science, Oxford, 1997), p. 581], it is found that fast ion stabilization can be dominated by anisotropic fluid effects rather than kinetic effects. In contrast, for predominantly trapped populations, the anisotropic fluid effects are destabilizing and thus reduce the stabilizing role of fast ions. This is especially evident for cases where the subsonic sheared toroidal plasma rotation induced by unbalanced NBI reduces kinetic stabilization. Sheared plasma rotation orientated either co or counter to the plasma current can reduce fast ion stabilization, but counter-rotation has the greatest effect by impeding the conservation of the third adiabatic invariant.

  5. Deflagration wave formed by ion beam, 3

    International Nuclear Information System (INIS)

    Niu, Keishiro; Abe, Takashi; Tamba, Moritake.

    1980-01-01

    An analysis is given for the structure of the deflagration wave which is formed in a target bombarded by an ion beam. Stationary deflagration and/or detonation waves are formed at the surface of the target in a case in which the reaction energy of direct fusion and/or the beam energy deposited in the target are less than a critical value. On the other hand, no solution for stationary wave exists, if the energy deposited in the wave exceeds a critical value. In the latter case, the time-dependent fundamental equations reduce approximately to a self-similar type of equations. Numerical integrations are carried out for this type of differential equations, and an example of self-similar deflagration wave numerically obtained is plotted in the figures. (author)

  6. Electron beam propagation in the ion focused regime (IFR) with the experimental test accelerator (ETA)

    International Nuclear Information System (INIS)

    Struve, K.W.; Lauer, E.J.; Chambers, F.W.

    1983-01-01

    The IFR is a well-known stable, low pressure (0.10 to 0.120 torr in air) propagation window. Secondary electrons created by collisions of beam electrons with gas atoms are rapidly expelled by the strong radial electric field of the beam charge. The ions that remain inside the beam partially neutralize the electric field, allowing magnetic pinch forces to focus the beam. Experiments with the ETA beam have re-verified this stable window and are reported. Image forces from a close wall IFR propagation tank are also experimentally shown to center the beam and damp transverse oscillations. Results of experiments using 5 and 15 cm dia beam tubes are reported. For p tau > 2 torr-nsec (gas pressure x time into pulse the beam charge becomes completely neutralized by the ions, allowing a build up of plasma and resultant beam-plasma instabilities. The onset of these instabilities has been measured using rf pickup loops (0 to 2 GHz) and microwave detectors (6 to 40 GHz), and are also reported

  7. A Spectroscopic Study of Impurity Behavior in Neutral-beam and Ohmically Heated TFTR Discharges

    Science.gov (United States)

    Stratton, B. C.; Ramsey, A. T.; Boody, F. P.; Bush, C. E.; Fonck, R. J.; Groenbner, R. J.; Hulse, R. A.; Richards, R. K.; Schivell, J.

    1987-02-01

    Quantitative spectroscopic measurements of Z{sub eff}, impurity densities, and radiated power losses have been made for ohmic- and neutral-beam-heated TFTR discharges at a plasma current of 2.2 MA and toroidal field of 4.7 T. Variations in these quantities with line-average plasma density (anti n{sub e}) and beam power up to 5.6 MW are presented for discharges on a graphite movable limiter. A detailed discussion of the use of an impurity transport model to infer absolute impurity densities and radiative losses from line intensity and visible continuum measurements is given. These discharges were dominated by low-Z impurities with carbon having a considerably higher density than oxygen, except in high-anti n{sub e} ohmic discharges, where the densities of carbon and oxygen were comparable. Metallic impurity concentrations and radiative losses were small, resulting in hollow radiated power profiles and fractions of the input power radiated being 30 to 50% for ohmic heating and 30% or less with beam heating. Spectroscopic estimates of the radiated power were in good agreement with bolometrically measured values. Due to an increase in the carbon density, Z{sub eff} rose from 2.0 to 2.8 as the beam power increased from 0 to 5.6 MW, pointing to a potentially serious dilution of the neutron-producing plasma ions as the beam power increased. Both the low-Z and metallic impurity concentrations were approximately constant with minor radius, indicating no central impurity accumulation in these discharges.

  8. Development of a focused ion beam micromachining system

    Energy Technology Data Exchange (ETDEWEB)

    Pellerin, J.G.; Griffis, D.; Russell, P.E.

    1988-12-01

    Focused ion beams are currently being investigated for many submicron fabrication and analytical purposes. An FIB micromachining system consisting of a UHV vacuum system, a liquid metal ion gun, and a control and data acquisition computer has been constructed. This system is being used to develop nanofabrication and nanomachining techniques involving focused ion beams and scanning tunneling microscopes.

  9. 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

  10. Focused Ion Beam Fabrication of Microelectronic Structures

    Science.gov (United States)

    1990-12-01

    Focused Ion Beams and Applications, Portland, OR Dec. 1990. 28. Y.L. Wang, H. Temkin , L.R. Harriott, R.A. Logan, and T. Tanban-Ek. Appi. Phys. Lett. 571864...been used.(2 8 ,3 0) In addition, in-situ measurement of adsorption rates and deposition rates can be readily obtained by using a quartz crystal...not well understood at the present time. Possible rate limiting steps in this process " .. are adsorption of molecules, decomposition of molecules, and

  11. Probing surface magnetism with ion beams

    International Nuclear Information System (INIS)

    Winter, H.

    2007-01-01

    Ion beams can be used to probe magnetic properties of surfaces by a variety of different methods. Important features of these methods are related to trajectories of atomic projectiles scattered from the surface of a solid target and to the electronic interaction mechanisms in the surface region. Both items provide under specific conditions a high sensitivity for the detection of magnetic properties in the region at the topmost layer of surface atoms. This holds in particular for scattering under planar surface channeling conditions, where under grazing impact atoms or ions are reflected specularly from the surface without penetration into the subsurface region. Two different types of methods are employed based on the detection of the spin polarization of emitted or captured electrons and on spin blocking effects for capture into atomic terms. These techniques allow one to probe the long range and short range magnetic order in the surface region

  12. PIC (Particle-in-Cell) simulation study on the beam extraction of intense ECR ion source

    International Nuclear Information System (INIS)

    Yang Yao; Zhang Wenhui; Ma Hongyi; Wu Qi; Fang Xing; Liu Zhanwen; Zhao Hongwei; Yao Ze'en

    2012-01-01

    Electromagnetic particle tracking program MAGIC was used to perform the simulation of beam extraction from high current ECR (Electron Cyclotron Resonance) ion source in this paper. The process of beam particles collision with residual gas was included in the simulation and the spatial distribution patterns of secondary electrons and slow ions from residual gas ionization were shown. Issues of radial space charge self-field, current density distribution and beam emittance were discussed. Simulation results illustrated that beam emittance grows quickly (about 3 times) in the extraction space, the space charge self-field would be neutralized partially by secondary electrons, which makes emittance down. Simulation figures also show that slow ions accumulation is an important contributing factor of negative bias electrode ignition, and this problem was described in the paper. (authors)

  13. Preliminary results of spatially resolved ECR ion beam profile investigations

    International Nuclear Information System (INIS)

    Panitzsch, L.; Stalder, M.; Wimmer-Schweingruber, R.F.

    2012-01-01

    The profile of an ion beam produced in an Electron Cyclotron Resonance Ion Source (ECRIS) can vary greatly depending on the source settings and the ion-optical tuning. Strongly focussed ion beams form circular structures (hollow beams) as predicted by simulations and observed in experiments. Each of the rings is predicted to be dominated by ions with same or at least similar m/q-ratios due to ion-optical effects. To check this we performed a series of preliminary investigations to test the required tuning capabilities of our ion source. This includes beam focussing (A) and beam steering (B) using a 3D-movable extraction. Having tuned the source to deliver a beam of strongly focussed ions of different ion species and having steered this beam to match the transmittance area of the sector magnet we also recorded the ion charge state distribution of the strongly focussed beam profile at different, spatially limited positions (C). The preliminary results will be introduced within this paper: it appears that our 3D-movable extraction is very efficient to steer and to focus the beam strongly. The paper is followed by the slides of the presentation. (authors)

  14. Collective Focusing of Intense Ion Beam Pulses for High-energy Density Physics Applications

    International Nuclear Information System (INIS)

    Dorf, Mikhail A.; Kaganovich, Igor D.; Startsev, Edward A.; Davidson, Ronald C.

    2011-01-01

    The collective focusing concept in which a weak magnetic lens provides strong focusing of an intense ion beam pulse carrying a neutralizing electron background is investigated by making use of advanced particle-in-cell simulations and reduced analytical models. The original analysis by Robertson Phys. Rev. Lett. 48, 149 (1982) is extended to the parameter regimes of particular importance for several high-energy density physics applications. The present paper investigates (1) the effects of non-neutral collective focusing in a moderately strong magnetic field; (2) the diamagnetic effects leading to suppression of the applied magnetic field due to the presence of the beam pulse; and (3) the influence of a finite-radius conducting wall surrounding the beam cross-section on beam neutralization. In addition, it is demonstrated that the use of the collective focusing lens can significantly simplify the technical realization of the final focusing of ion beam pulses in the Neutralized Drift Compression Experiment-I (NDCX-I), and the conceptual designs of possible experiments on NDCX-I are investigated by making use of advanced numerical simulations.

  15. Important atomic physics issues for ion beam fusion

    International Nuclear Information System (INIS)

    Bangerter, R.O.

    1985-01-01

    This paper suggests several current atomic physics questions important to ion beam fusion. Among the topics discussed are beam transport, beam-target interaction, and reactor design. The major part of the report is discussion concerning areas of research necessary to better understand beam-target interactions

  16. Recent radioactive ion beam program at RIKEN and related topics

    Indian Academy of Sciences (India)

    Recent experimental programs at RIKEN concerning RI beams are reviewed. RIKEN has the ring cyclotron (RRC) with high intense heavy-ion beams and large acceptance fragment separator, RIPS. The complex can provide high intense RI-beams. By using the high intense RI-beams, a variety of experiments have been ...

  17. Heavy ion beam probe development for the plasma potential measurement on the TUMAN-3M tokamak

    International Nuclear Information System (INIS)

    Askinazi, L.G.; Kornev, V.A.; Lebedev, S.V.; Tukachinsky, A.S.; Zhubr, N.A.; Dreval, N.B.; Krupnik, L.I.

    2004-01-01

    The peculiarities of the heavy ion beam probe implementation on the small aspect ratio tokamak TUMAN-3M are analyzed. The toroidal displacement of beam trajectory due to the high I pl /B tor ratio is taken into account when designing the layout of the diagnostic. Numerical calculation of beam trajectories using realistic configuration of TUMAN-3M magnetic fields and parabolic plasma current profile resulted in proper adjustment of probing and detection parameters (probing ion material, energy, entrance angles, detector location, and orientation). Secondary ion energy analyzer gain functions G and F were measured in situ using neutral hydrogen puffed in the tokamak vessel as a target for secondary ions production. The detector unit featured split-plate design and had additional electrodes for secondary electron emission suppression. As a result, the diagnostic is now capable of plasma potential evolution measurement and is sensitive enough to trace the potential profile evolution at the L-H mode transition

  18. 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

  19. Supersonic plasma beams with controlled speed generated by the alternative low power hybrid ion engine (ALPHIE) for space propulsion

    Science.gov (United States)

    Conde, L.; Domenech-Garret, J. L.; Donoso, J. M.; Damba, J.; Tierno, S. P.; Alamillo-Gamboa, E.; Castillo, M. A.

    2017-12-01

    The characteristics of supersonic ion beams from the alternative low power hybrid ion engine (ALPHIE) are discussed. This simple concept of a DC powered plasma accelerator that only needs one electron source for both neutral gas ionization and ion beam neutralization is also examined. The plasma production and space charge neutralization processes are thus coupled in this plasma thruster that has a total DC power consumption of below 450 W, and uses xenon or argon gas as a propellant. The operation parameters of the plasma engine are studied in the laboratory in connection with the ion energy distribution function obtained with a retarding-field energy analyzer. The ALPHIE plasma beam expansion produces a mesothermal plasma flow with two-peaked ion energy distribution functions composed of low and high speed ion groups. The characteristic drift velocities of the fast ion groups, in the range 36.6-43.5 Km/s, are controlled by the acceleration voltage. These supersonic speeds are higher than the typical ion sound velocities of the low energy ion group produced by the expansion of the plasma jet. The temperatures of the slow ion population lead to ion Debye lengths longer than the electron Debye lengths. Furthermore, the electron impact ionization can coexist with collisional ionization by fast ions downstream the grids. Finally, the performance characteristics and comparisons with other plasma accelerator schemes are also discussed.

  20. 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.