Sample records for ion beam laboratory

  1. LANL: Ion Beam Materials Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9 5 - -/e),,s - 6157Bioenergy » CPO: LosUniqueIon

  2. Spontaneous ion beam formation in the laboratory, space, and simulation

    SciTech Connect (OSTI)

    Carr, J. Jr.; Cassak, P. A.; Galante, M.; Keesee, A. M.; Lusk, G.; Magee, R. M.; McCarren, D.; Scime, E. E.; Sears, S.; Vandervort, R. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States)] [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States); Gulbrandsen, N. [University of Tromsø, Tromsø (Norway)] [University of Tromsø, Tromsø (Norway); Goldman, Martin; Newman, David [Department of Physics, University of Colorado–Boulder, Boulder, Colorado 80309 (United States)] [Department of Physics, University of Colorado–Boulder, Boulder, Colorado 80309 (United States); Eastwood, J. P. [The Blackett Laboratory, Imperial College London, London SW7 2AZ (United Kingdom)] [The Blackett Laboratory, Imperial College London, London SW7 2AZ (United Kingdom)

    2013-07-15T23:59:59.000Z

    We present experimental evidence for the spontaneous formation of multiple double layers within a single divergent magnetic field structure. Downstream of the divergent magnetic field, multiple accelerated ion populations are observed. The similarity of the accelerated ion populations observed in these laboratory experiments to ion populations observed in the magnetosphere and in numerical simulations suggests that the observation of a complex ion velocity distribution alone is insufficient to distinguish between simple plasma expansion and magnetic reconnection. Further, the effective temperature of the aggregate ion population is significantly larger than the temperatures of the individual ion population components, suggesting that insufficiently resolved measurements could misidentify multiple beam creation as ion heating. Ions accelerated in randomly oriented electric fields that mimic heating would have an ion heating rate dependent on the ion charge and mass that is qualitatively consistent with recent experimental observations of ion heating during magnetic reconnection.

  3. The Heavy Ion Fusion Science Virtual National Laboratory Status of heavy-ion-beam-driven

    E-Print Network [OSTI]

    .2,Qin, H.3, Rose, D.V.4, Roy, P.K.1, Startsev, E.A.3, Seidl, P.A.1, Sharp, W.M.2, Vay, J-L.1. [Neutralized Drift Compression Experiment (NDCX): P. K. Roy, et. al. Phys. Rev. Lett. 95, 234801 (2005), and J, compressing beam ~ 2 ns FWHM *cf Roy, et. Al. PRL 95(2005) 23481 2800 K (will be higher after emissivity

  4. Broad beam ion implanter

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA)

    1996-01-01T23:59:59.000Z

    An ion implantation device for creating a large diameter, homogeneous, ion beam is described, as well as a method for creating same, wherein the device is characterized by extraction of a diverging ion beam and its conversion by ion beam optics to an essentially parallel ion beam. The device comprises a plasma or ion source, an anode and exit aperture, an extraction electrode, a divergence-limiting electrode and an acceleration electrode, as well as the means for connecting a voltage supply to the electrodes.

  5. The Electron Beam Ion Source (EBIS)

    ScienceCinema (OSTI)

    Brookhaven Lab

    2010-01-08T23:59:59.000Z

    Brookhaven National Lab has successfully developed a new pre-injector system, called the Electron Beam Ion Source, for the Relativistic Heavy Ion Collider (RHIC) and NASA Space Radiation Laboratory science programs. The first of several planned improvemen

  6. Focused ion beam system

    DOE Patents [OSTI]

    Leung, K.; Gough, R.A.; Ji, Q.; Lee, Y.Y.

    1999-08-31T23:59:59.000Z

    A focused ion beam (FIB) system produces a final beam spot size down to 0.1 {mu}m or less and an ion beam output current on the order of microamps. The FIB system increases ion source brightness by properly configuring the first (plasma) and second (extraction) electrodes. The first electrode is configured to have a high aperture diameter to electrode thickness aspect ratio. Additional accelerator and focusing electrodes are used to produce the final beam. As few as five electrodes can be used, providing a very compact FIB system with a length down to only 20 mm. Multibeamlet arrangements with a single ion source can be produced to increase throughput. The FIB system can be used for nanolithography and doping applications for fabrication of semiconductor devices with minimum feature sizes of 0.1 m or less. 13 figs.

  7. Pulsed ion beam source

    DOE Patents [OSTI]

    Greenly, John B. (Lansing, NY)

    1997-01-01T23:59:59.000Z

    An improved pulsed ion beam source having a new biasing circuit for the fast magnetic field. This circuit provides for an initial negative bias for the field created by the fast coils in the ion beam source which pre-ionize the gas in the source, ionize the gas and deliver the gas to the proper position in the accelerating gap between the anode and cathode assemblies in the ion beam source. The initial negative bias improves the interaction between the location of the nulls in the composite magnetic field in the ion beam source and the position of the gas for pre-ionization and ionization into the plasma as well as final positioning of the plasma in the accelerating gap. Improvements to the construction of the flux excluders in the anode assembly are also accomplished by fabricating them as layered structures with a high melting point, low conductivity material on the outsides with a high conductivity material in the center.

  8. An overview of the facilities, activities, and developments at the University of North Texas Ion Beam Modification and Analysis Laboratory (IBMAL)

    SciTech Connect (OSTI)

    Rout, Bibhudutta; Dhoubhadel, Mangal S.; Poudel, Prakash R.; Kummari, Venkata C.; Pandey, Bimal; Deoli, Naresh T.; Lakshantha, Wickramaarachchige J.; Mulware, Stephen J.; Baxley, Jacob; Manuel, Jack E.; Pacheco, Jose L.; Szilasi, Szabolcs; Weathers, Duncan L.; Reinert, Tilo; Glass, Gary A.; Duggan, Jerry L.; McDaniel, Floyd D. [Ion Beam Modification and Analysis Laboratory, University of North Texas, Department of Physics, 1155 Union Circle 311427, Denton, Texas 76203 (United States)

    2013-07-03T23:59:59.000Z

    The Ion Beam Modification and Analysis Laboratory (IBMAL) at the University of North Texas includes several accelerator facilities with capabilities of producing a variety of ion beams from tens of keV to several MeV in energy. The four accelerators are used for research, graduate and undergraduate education, and industrial applications. The NEC 3MV Pelletron tandem accelerator has three ion sources for negative ions: He Alphatross and two different SNICS-type sputter ion sources. Presently, the tandem accelerator has four high-energy beam transport lines and one low-energy beam transport line directly taken from the negative ion sources for different research experiments. For the low-energy beam line, the ion energy can be varied from {approx}20 to 80 keV for ion implantation/modification of materials. The four post-acceleration beam lines include a heavy-ion nuclear microprobe; multi-purpose PIXE, RBS, ERD, NRA, and broad-beam single-event upset; high-energy ion implantation line; and trace-element accelerator mass spectrometry. The NEC 3MV single-ended Pelletron accelerator has an RF ion source mainly for hydrogen, helium and heavier inert gases. We recently installed a capacitive liner to the terminal potential stabilization system for high terminal voltage stability and high-resolution microprobe analysis. The accelerator serves a beam line for standard RBS and RBS/C. Another beamline for high energy focused ion beam application using a magnetic quadrupole lens system is currently under construction. This beam line will also serve for developmental work on an electrostatic lens system. The third accelerator is a 200 kV Cockcroft-Walton accelerator with an RF ion source. The fourth accelerator is a 2.5 MV Van de Graaff accelerator, which was in operation for last several decades is currently planned to be used mainly for educational purpose. Research projects that will be briefly discussed include materials synthesis/modification for photonic, electronic, and magnetic applications, surface sputtering and micro-fabrication of materials, development of high-energy ion microprobe systems, and educational and outreach activities.

  9. Ion-beam technologies

    SciTech Connect (OSTI)

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

    1993-01-01T23:59:59.000Z

    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.

  10. Ion beam generating apparatus

    DOE Patents [OSTI]

    Brown, Ian G. (1088 Woodside Rd., Berkeley, CA 94708); Galvin, James (2 Commodore #276, Emeryville, CA 94608)

    1987-01-01T23:59:59.000Z

    An ion generating apparatus utilizing a vacuum chamber, a cathode and an anode in the chamber. A source of electrical power produces an arc or discharge between the cathode and anode. The arc is sufficient to vaporize a portion of the cathode to form a plasma. The plasma is directed to an extractor which separates the electrons from the plasma, and accelerates the ions to produce an ion beam.

  11. Ion beam generating apparatus

    DOE Patents [OSTI]

    Brown, I.G.; Galvin, J.

    1987-12-22T23:59:59.000Z

    An ion generating apparatus utilizing a vacuum chamber, a cathode and an anode in the chamber. A source of electrical power produces an arc or discharge between the cathode and anode. The arc is sufficient to vaporize a portion of the cathode to form a plasma. The plasma is directed to an extractor which separates the electrons from the plasma, and accelerates the ions to produce an ion beam. 10 figs.

  12. The Heavy Ion Fusion Science Virtual National Laboratory Recent advances in ion-beam-driven high energy density

    E-Print Network [OSTI]

    Laboratories under Contract Numbers DE-AC02-05CH1123 and W-7405-Eng-48, and by the Princeton Plasma Physics

  13. Ion beam lithography system

    DOE Patents [OSTI]

    Leung, Ka-Ngo

    2005-08-02T23:59:59.000Z

    A maskless plasma-formed ion beam lithography tool provides for patterning of sub-50 nm features on large area flat or curved substrate surfaces. The system is very compact and does not require an accelerator column and electrostatic beam scanning components. The patterns are formed by switching beamlets on or off from a two electrode blanking system with the substrate being scanned mechanically in one dimension. This arrangement can provide a maskless nano-beam lithography tool for economic and high throughput processing.

  14. Pulsed ion beam source

    DOE Patents [OSTI]

    Greenly, J.B.

    1997-08-12T23:59:59.000Z

    An improved pulsed ion beam source is disclosed having a new biasing circuit for the fast magnetic field. This circuit provides for an initial negative bias for the field created by the fast coils in the ion beam source which pre-ionize the gas in the source, ionize the gas and deliver the gas to the proper position in the accelerating gap between the anode and cathode assemblies in the ion beam source. The initial negative bias improves the interaction between the location of the nulls in the composite magnetic field in the ion beam source and the position of the gas for pre-ionization and ionization into the plasma as well as final positioning of the plasma in the accelerating gap. Improvements to the construction of the flux excluders in the anode assembly are also accomplished by fabricating them as layered structures with a high melting point, low conductivity material on the outsides with a high conductivity material in the center. 12 figs.

  15. Beams 92: Proceedings. Volume 2, Ion beams, electron beams, diagnostics

    SciTech Connect (OSTI)

    Mosher, D.; Cooperstein, G. [eds.] [Naval Research Lab., Washington, DC (United States)] [eds.; Naval Research Lab., Washington, DC (United States)

    1993-12-31T23:59:59.000Z

    This report contains papers on the following topics. Ion beam papers; electron beam papers; and these papers have been indexed separately elsewhere.

  16. Laser acceleration of ion beams

    E-Print Network [OSTI]

    I. A. Egorova; A. V. Filatov; A. V. Prozorkevich; S. A. Smolyansky; D. B. Blaschke; M. Chubaryan

    2007-02-01T23:59:59.000Z

    We consider methods of charged particle acceleration by means of high-intensity lasers. As an application we discuss a laser booster for heavy ion beams provided, e.g. by the Dubna nuclotron. Simple estimates show that a cascade of crossed laser beams would be necessary to provide additional acceleration to gold ions of the order of GeV/nucleon.

  17. Maskless, resistless ion beam lithography

    SciTech Connect (OSTI)

    Ji, Qing

    2003-03-10T23:59:59.000Z

    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{sub 2}{sup +}, BF{sub 2}{sup +}, P{sup +} etc., for surface modification and doping applications. With optimized source condition, around 85% of BF{sub 2}{sup +}, over 90% of O{sub 2}{sup +} and P{sup +} 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{sup +} beam is as high as 440 A/cm{sup 2} {center_dot} Sr, which represents a 30x improvement over prior work. Direct patterning of Si thin film using a focused O{sub 2}{sup +} ion beam has been investigated. A thin surface oxide film can be selectively formed using 3 keV O{sub 2}{sup +} ions with the dose of 10{sup 15} cm{sup -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{sup +} beam implantation at 5 keV is also presented. With implantation dose of around 10{sup 16} cm{sup -2}, the electron concentration is about 2.5 x 10{sup 18} cm{sup -3} and electron mobility is around 200 cm{sup 2}/V{center_dot}s. To demonstrate the suitability of scanning FIB lithography for the manufacture of integrated circuit devices, SOI MOSFET fabrication using the maskless, resistless ion beam lithography is demonstrated. An array of microcolumns can be built by stacking multi-aperture electrode and insulator layers. Because the multicusp plasma source can achieve uniform ion density over a large area, it can be used in conjunction with the array of microcolumns, for massively parallel FIB processing to achieve reasonable exposure throughput.

  18. Oxygen ion-beam microlithography

    DOE Patents [OSTI]

    Tsuo, Y. Simon (Lakewood, CO)

    1991-01-01T23:59:59.000Z

    A method of providing and developing a resist on a substrate for constructing integrated circuit (IC) chips includes the following steps: of depositing a thin film of amorphous silicon or hydrogenated amorphous silicon on the substrate and exposing portions of the amorphous silicon to low-energy oxygen ion beams to oxidize the amorphous silicon at those selected portions. The nonoxidized portions are then removed by etching with RF-excited hydrogen plasma. Components of the IC chip can then be constructed through the removed portions of the resist. The entire process can be performed in an in-line vacuum production system having several vacuum chambers. Nitrogen or carbon ion beams can also be used.

  19. Oxygen ion-beam microlithography

    DOE Patents [OSTI]

    Tsuo, Y.S.

    1991-08-20T23:59:59.000Z

    A method of providing and developing a resist on a substrate for constructing integrated circuit (IC) chips includes the following steps: of depositing a thin film of amorphous silicon or hydrogenated amorphous silicon on the substrate and exposing portions of the amorphous silicon to low-energy oxygen ion beams to oxidize the amorphous silicon at those selected portions. The nonoxidized portions are then removed by etching with RF-excited hydrogen plasma. Components of the IC chip can then be constructed through the removed portions of the resist. The entire process can be performed in an in-line vacuum production system having several vacuum chambers. Nitrogen or carbon ion beams can also be used. 5 figures.

  20. Focused electron and ion beam systems

    DOE Patents [OSTI]

    Leung, Ka-Ngo; Reijonen, Jani; Persaud, Arun; Ji, Qing; Jiang, Ximan

    2004-07-27T23:59:59.000Z

    An electron beam system is based on a plasma generator in a plasma ion source with an accelerator column. The electrons are extracted from a plasma cathode in a plasma ion source, e.g. a multicusp plasma ion source. The beam can be scanned in both the x and y directions, and the system can be operated with multiple beamlets. A compact focused ion or electron beam system has a plasma ion source and an all-electrostatic beam acceleration and focusing column. The ion source is a small chamber with the plasma produced by radio-frequency (RF) induction discharge. The RF antenna is wound outside the chamber and connected to an RF supply. Ions or electrons can be extracted from the source. A multi-beam system has several sources of different species and an electron beam source.

  1. Pseudo ribbon metal ion beam source

    SciTech Connect (OSTI)

    Stepanov, Igor B., E-mail: stepanovib@tpu.ru; Ryabchikov, Alexander I.; Sivin, Denis O.; Verigin, Dan A. [Tomsk Polytechnic University, 30 Lenina Avenue, Tomsk 634050 (Russian Federation)] [Tomsk Polytechnic University, 30 Lenina Avenue, Tomsk 634050 (Russian Federation)

    2014-02-15T23:59:59.000Z

    The paper describes high broad metal ion source based on dc macroparticle filtered vacuum arc plasma generation with the dc ion-beam extraction. The possibility of formation of pseudo ribbon beam of metal ions with the parameters: ion beam length 0.6 m, ion current up to 0.2 A, accelerating voltage 40 kV, and ion energy up to 160 kV has been demonstrated. The pseudo ribbon ion beam is formed from dc vacuum arc plasma. The results of investigation of the vacuum arc evaporator ion-emission properties are presented. The influence of magnetic field strength near the cathode surface on the arc spot movement and ion-emission properties of vacuum-arc discharge for different cathode materials are determined. It was shown that vacuum-arc discharge stability can be reached when the magnetic field strength ranges from 40 to 70 G on the cathode surface.

  2. Intense ion beam propagation in a reactor sized chamber

    E-Print Network [OSTI]

    Vay, J.L.; Deutsch, C.

    2000-01-01T23:59:59.000Z

    beams in a heavy ion fusion reactor chamber filled with lowIon Fusion, Intense Ion Beams, Reaction Chamber. P.A.C.S.heavy ion beam propagation in the reaction chamber, Fus.

  3. Heavy Ion Fusion Science Virtual National Laboratory

    E-Print Network [OSTI]

    line- of-sight damage from target debris, neutron and gamma radiation. · Target injection: Heavy ions-liquid-protected target chambers with 30 yr lifetimes. · Robust final optics: Focusing magnets for ion beams avoid direct

  4. Focused ion beam source method and apparatus

    DOE Patents [OSTI]

    Pellin, Michael J. (Naperville, IL); Lykke, Keith R. (Gaithersburg, MD); Lill, Thorsten B. (Sunnyvale, CA)

    2000-01-01T23:59:59.000Z

    A focused ion beam having a cross section of submicron diameter, a high ion current, and a narrow energy range is generated from a target comprised of particle source material by laser ablation. The method involves directing a laser beam having a cross section of critical diameter onto the target, producing a cloud of laser ablated particles having unique characteristics, and extracting and focusing a charged particle beam from the laser ablated cloud. The method is especially suited for producing focused ion beams for semiconductor device analysis and modification.

  5. Summary II - Fusion Ion sources, Beam Formation, Acceleration and Neutralisation

    SciTech Connect (OSTI)

    Jones, T. T. C. [UKAEA Culham Division, Abingdon, OX14 3DB (United Kingdom)

    2007-08-10T23:59:59.000Z

    The 11th International Symposium on the Production and Neutralization of Negative Ions and Beams was held in Santa Fe, New Mexico on 13th - 15th September 2006 and was hosted by Los Alamos National Laboratory. This summary covers the sessions of the Symposium devoted to the topics listed in the title.

  6. Robust Collimation Control of Laser-Generated Ion Beam

    E-Print Network [OSTI]

    Kawata, S; Kamiyama, D; Nagashima, T; Barada, D; Gu, Y J; Li, X; Yu, Q; Kong, Q; Wang, P X

    2015-01-01T23:59:59.000Z

    The robustness of a structured collimation device is discussed for an intense-laser-produced ion beam. In this paper the ion beam collimation is realized by the solid structured collimation device, which produces the transverse electric field; the electric field contributes to reduce the ion beam transverse velocity and collimate the ion beam. Our 2.5 dimensional particle-in cell simulations demonstrate that the collimation device is rather robust against the changes in the laser parameters and the collimation target sizes. The intense short-pulse lasers are now available, and are used to generate an ion beam. The issues in the laser ion acceleration include an ion beam collimation, ion energy spectrum control, ion production efficiency, ion energy control, ion beam bunching, etc. The laser-produced ion beam tends to expand in the transverse and longitudinal directions during the ion beam propagation. The ion beam collimation is focused in this paper.

  7. ar ion beam: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the ion optical code IBSimu. The simulations predict self-consistently the triangular and hollow beam structures which are often observed experimentally with ECRIS ion beams. The...

  8. argon ion beam: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the ion optical code IBSimu. The simulations predict self-consistently the triangular and hollow beam structures which are often observed experimentally with ECRIS ion beams. The...

  9. Long Plasma Source for Heavy Ion Beam Charge Neutralization

    E-Print Network [OSTI]

    Efthimion, P.C.

    2009-01-01T23:59:59.000Z

    neutralizing plasma column the heavy ion beam can focus to aPlasmas are a source of unbound electrons for charge neutralizing intense heavy ion beams to focus

  10. Initial commissioning results with the NSCL Electron Beam Ion Trap

    SciTech Connect (OSTI)

    Schwarz, S.; Kittimanapun, K.; Lapierre, A.; Leitner, D.; Ottarson, J.; Portillo, M. [National Superconducting Cyclotron Laboratory, NSCL, Michigan State University, East Lansing, Michigan 48824 (United States); Bollen, G. [National Superconducting Cyclotron Laboratory, NSCL, Michigan State University, East Lansing, Michigan 48824 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States); Lopez-Urrutia, J. R. Crespo [Max-Planck Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Kester, O. [GSI Helmholtzzentrum fuer Schwerionenforschung, Planckstr. 1, 64291 Darmstadt (Germany)

    2012-02-15T23:59:59.000Z

    The ReA reaccelerator is being added to the National Superconducting Cyclotron Laboratory (NSCL) fragmentation facility in order to provide exotic rare-isotope beams, not available at the Isotope Separation On-Line facilities, in the several-MeV/u energy range. The first stage of the NSCL reaccelerator complex, consisting of an EBIT charge breeder, a room-temperature radiofrequency quadrupole (RFQ) accelerator, and superconducting linear accelerator modules, has been completed and is being put into operation. Commissioning of the EBIT has started by extracting charge-bred residual gas ions, ions created from a Ne gas jet directed across the EBIT's electron beam and ions captured from an external test ion source. Charge-bred ions from the Ne gas jet have been extracted as a pulse and accelerated through the RFQ and the two cryomodules.

  11. Plasma ion sources and ion beam technology inmicrofabrications

    SciTech Connect (OSTI)

    Ji, Lili

    2007-09-01T23:59:59.000Z

    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 (25 mm) at 25 keV beam voltage. Such an integrated FIB/SEM dual-beam system will not only improve the accuracy and reproducibility when performing ion beam sculpting and direct implantation processes, but will also enable researchers to perform cross-sectioning, imaging, and analysis with the same tool. A major advantage of this approach is the ability to produce a wide variety of ion species tailored to the application.

  12. Flow-through ion beam source

    DOE Patents [OSTI]

    Springer, R.W.

    1997-02-11T23:59:59.000Z

    A method and an apparatus for forming a charge neutral ion beam which is useful in producing thin films of material on electrically conductive or non-conductive substrates are provided. 4 figs.

  13. Ion beam processing of advanced electronic materials

    SciTech Connect (OSTI)

    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))

    1989-01-01T23:59:59.000Z

    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)

  14. INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMS

    SciTech Connect (OSTI)

    Sharp, W. M.; Friedman, A.; Grote, D. P.; Barnard, J. J.; Cohen, R. H.; Dorf, M. A.; Lund, S. M.; Perkins, L. J.; Terry, M. R.; Logan, B. G.; Bieniosek, F. M.; Faltens, A.; Henestroza, E.; Jung, J. Y.; Kwan, J. W.; Lee, E. P.; Lidia, S. M.; Ni, P. A.; Reginato, L. L.; Roy, P. K.; Seidl, P. A.; Takakuwa, J. H.; Vay, J.-L.; Waldron, W. L.; Davidson, R. C.; Gilson, E. P.; Kaganovich, I. D.; Qin, H.; Startsev, E.; Haber, I.; Kishek, R. A.; Koniges, A. E.

    2011-03-31T23:59:59.000Z

    Intense heavy-ion beams have long been considered a promising driver option for inertial-fusion energy production. This paper briefly compares inertial confinement fusion (ICF) to the more-familiar magnetic-confinement approach and presents some advantages of using beams of heavy ions to drive ICF instead of lasers. Key design choices in heavy-ion fusion (HIF) facilities are discussed, particularly the type of accelerator. We then review experiments carried out at Lawrence Berkeley National Laboratory (LBNL) over the past thirty years to understand various aspects of HIF driver physics. A brief review follows of present HIF research in the US and abroad, focusing on a new facility, NDCX-II, being built at LBNL to study the physics of warm dense matter heated by ions, as well as aspects of HIF target physics. Future research directions are briefly summarized.

  15. Beam current controller for laser ion source

    DOE Patents [OSTI]

    Okamura, Masahiro

    2014-10-28T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Spädtke, Peter, E-mail: p.spaedtke@gsi.de [GSI Helmholtzzentrum für Schwerionenforschung GmbH (Germany)] [GSI Helmholtzzentrum für Schwerionenforschung GmbH (Germany)

    2014-02-15T23:59:59.000Z

    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.

  17. The uses of electron beam ion traps in the study of highly charged ions

    SciTech Connect (OSTI)

    Knapp, D.

    1994-11-02T23:59:59.000Z

    The Electron Beam Ion Trap (EBIT) is a relatively new tool for the study of highly charged ions. Its development has led to a variety of new experimental opportunities; measurements have been performed with EBITs using techniques impossible with conventional ion sources or storage rings. In this paper, I will highlight the various experimental techniques we have developed and the results we have obtained using the EBIT and higher-energy Super-EBIT built at the Lawrence Livermore National Laboratory. The EBIT employs a high-current-density electron beam to trap, ionize, and excite a population of ions. The ions can be studied in situ or extracted from the trap for external experiments. The trapped ions form an ionization-state equilibrium determined by the relative ionization and recombination rates. Ions of several different elements may simultaneously be present in the trap. The ions are nearly at rest, and, for most systems, all in their ground-state configurations. The electron-ion interaction energy has a narrow distribution and can be varied over a wide range. We have used the EBIT devices for the measurement of electron-ion interactions, ion structure, ion-surface interactions, and the behavior of low-density plasmas.

  18. BROOKHAVEN NATIONAL LABORATORY'S HIGH FLUX BEAM REACTOR

    E-Print Network [OSTI]

    Ohta, Shigemi

    1 BROOKHAVEN NATIONAL LABORATORY'S HIGH FLUX BEAM REACTOR Compiled by S. M. Shapiro I. PICTORIAL with fiberglass insulation and a protective aluminum skin. The reactor vessel is shaped somewhat like a very large at the spherical end. It is located at the center of the reactor building and is surrounded by a lead and steel

  19. ELECTRON BEAM ION SOURCE PREINJECTOR PROJECT (EBIS) CONCEPTUAL DESIGN REPORT.

    SciTech Connect (OSTI)

    ALESSI, J.; BARTON, D.; BEEBE, E.; GASSNER, D.; GRANDINETTI, R.; HSEUH, H.; JAVIDFAR, A.; KPONOU, A.; LAMBIASE, R.; LESSARD, E.; LOCKEY, R.; LODESTRO, V.; MAPES, M.; MIRABELLA, D.; NEHRING, T.; OERTER, B.; PENDZICK, A.; PIKIN, A.; RAPARIA, D.; RITTER, J.; ROSER, T.; RUSSO, T.; SNYDSTRUP, L.; WILINSKI, M.; ZALTSMAN, A.; ZHANG, S.

    2005-09-01T23:59:59.000Z

    This report describes a new heavy ion pre-injector for the Relativistic Heavy Ion Collider (RHIC) based on a high charge state Electron Beam Ion Source (EBIS), a Radio Frequency Quadrupole (RFQ) accelerator, and a short Linear accelerator (Linac). The highly successful development of an EBIS at Brookhaven National Laboratory (BNL) now makes it possible to replace the present pre-injector that is based on an electrostatic Tandem with a reliable, low maintenance Linac-based pre-injector. Linac-based preinjectors are presently used at most accelerator and collider facilities with the exception of RHIC, where the required gold beam intensities could only be met with a Tandem until the recent EBIS development. EBIS produces high charge state ions directly, eliminating the need for the two stripping foils presently used with the Tandem. Unstable stripping efficiencies of these foils are a significant source of luminosity degradation in RHIC. The high reliability and flexibility of the new Linac-based pre-injector will lead to increased integrated luminosity at RHIC and is an essential component for the long-term success of the RHIC facility. This new pre-injector, based on an EBIS, also has the potential for significant future intensity increases and can produce heavy ion beams of all species including uranium beams and, as part of a future upgrade, might also be used to produce polarized {sup 3}He beams. These capabilities will be critical to the future luminosity upgrades and electron-ion collisions in RHIC. The proposed pre-injector system would also provide for a major enhancement in capability for the NASA Space Radiation Laboratory (NSRL), which utilizes heavy-ion beams from the RHIC complex. EBIS would allow for the acceleration of all important ion species for the NASA radiobiology program, such as, helium, argon, and neon which are unavailable with the present Tandem injector. In addition, the new system would allow for very rapid switching of ion species for NSRL experiments, reducing delays due to the interference with RHIC injection operations, and allowing enhanced mixed field radiation studies. The new RFQ and Linac that are used to accelerate beams from the EBIS to an energy sufficient for injection into the Booster are both very similar to existing devices already in operation at other facilities. Injection into the Booster will occur at the same location as the existing injection from the Tandem.

  20. Intense Ion Beam for Warm Dense Matter Physics

    SciTech Connect (OSTI)

    Coleman, Joshua Eugene

    2008-05-23T23:59:59.000Z

    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{sup +} 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 improved experimental and calculated axial focus (> 100 x axial compression, < 2 ns pulses) and higher peak energy deposition on target are also presented. These achievements demonstrate the capabilities for near term target heating experiments to T{sub e} {approx} 0.1 eV and for future ion accelerators to heat targets to T{sub e} > 1 eV.

  1. Generation, transport and focusing of high-brightness heavy ion beams

    E-Print Network [OSTI]

    Henestroza, Enrique

    2006-01-01T23:59:59.000Z

    The Neutralized Transport Experiment (NTX) has been built at the Heavy Ion Fusion Virtual National Laboratory. NTX is the first successful integrated beam system experiment that explores various physical phenomena, and ...

  2. Ion beam extractor with counterbore

    DOE Patents [OSTI]

    Ji, Qing; Standiford, Keith; King, Tsu-Jae; Leung, Ka-Ngo

    2006-08-01T23:59:59.000Z

    An extractor system for a plasma ion source has a single (first) electrode with one or more apertures, or a pair of spaced electrodes, a first or plasma forming electrode and a second or extraction electrode, with one or more aligned apertures. The aperture(s) in the first electrode (or the second electrode or both) have a counterbore on the downstream side (i.e. away from the plasma ion source or facing the second electrode). The counterbored extraction system reduces aberrations and improves focusing. The invention also includes an ion source with the counterbored extraction system, and a method of improving focusing in an extraction system by providing a counterbore.

  3. The Scientific program with RIBRAS (Radioactive Ion Beams in Brasil)

    SciTech Connect (OSTI)

    Lichtenthaeler, R.; Lepine-Szily, A.; Guimaraes, V.; Faria, P. N. de; Mendes, D. R. Jr.; Pires, K. C. C.; Morcelle, V.; Hussein, M. S.; Barioni, A.; Condori, R. Pampa; Morais, M. C.; Alcantara Nunez, J.; Camargo, O. Jr.; Otani, Y.; Leistenschneider, E.; Scarduelli, V. [Instituto de Fisica da Universidade de Sao Paulo, C.P. 66318, 05389-970 Sao Paulo (Brazil); Benjamim, E. A. [Universidad de Santiago de Compostela, Depto. Fisica Particulas, Facultad Fisica, Campus Sur s/n 15786 Santiago de Compostela (Spain) (Spain); Moro, A. M. [Departamento de FAMN, Universidad de Sevilla, Apdo 1065, E-41080, Sevilla (Spain); Arazi, A. [Laboratorio Tandar, Departamento de Fisica, Comision Nacional de Energia Atomica, Av. del Libertador 8250, (1429), Buenos Aires (Argentina); Assuncao, M. [UNIFESP-Campus de Diadema, SP (Brazil)] (and others)

    2009-06-03T23:59:59.000Z

    The Radioactive Ion Beams Facility (RIBRAS) is in operation since 2004 at the Pelletron Accelerator Laboratory of the University of Sao Paulo and consists of two superconducting solenoids capable of producing low energy secondary beams of light exotic nuclei. Measurements of the elastic scattering, breakup and transfer reactions with radioactive projectiles such as {sup 6}He,{sup 8}Li,{sup 7}Be on several targets have been performed. A review of the research program carried on along the last four years using the RIBRAS facility is presented.

  4. World record neutron beam at Los Alamos National Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    World record neutron beam at LANL World record neutron beam at Los Alamos National Laboratory Scientists have created the largest neutron beam ever made by a short-pulse laser,...

  5. Ion beam assisted deposition of thermal barrier coatings

    DOE Patents [OSTI]

    Youchison, Dennis L. (Albuquerque, NM); McDonald, Jimmie M. (Albuquerque, NM); Lutz, Thomas J. (Albuquerque, NM); Gallis, Michail A. (Albuquerque, NM)

    2010-11-23T23:59:59.000Z

    Methods and apparatus for depositing thermal barrier coatings on gas turbine blades and vanes using Electron Beam Physical Vapor Deposition (EBPVD) combined with Ion Beam Assisted Deposition (IBAD).

  6. Physics with fast molecular-ion beams

    SciTech Connect (OSTI)

    Kanter, E.P.

    1980-01-01T23:59:59.000Z

    Fast (MeV) molecular-ion beams provide a unique source of energetic projectile nuclei which are correlated in space and time. The recognition of this property has prompted several recent investigations of various aspects of the interactions of these ions with matter. High-resolution measurements on the fragments resulting from these interactions have already yielded a wealth of new information on such diverse topics as plasma oscillations in solids and stereochemical structures of molecular ions as well as a variety of atomic collision phenomena. The general features of several such experiments will be discussed and recent results will be presented.

  7. Focused ion beam micromilling and articles therefrom

    DOE Patents [OSTI]

    Lamartine, B.C.; Stutz, R.A.

    1998-06-30T23:59:59.000Z

    An ultrahigh vacuum focused ion beam micromilling apparatus and process are disclosed. Additionally, a durable data storage medium using the micromilling process is disclosed, the durable data storage medium capable of storing, e.g., digital or alphanumeric characters as well as graphical shapes or characters. 6 figs.

  8. Temperature-dependent ion beam mixing

    SciTech Connect (OSTI)

    Rehn, L.E.; Alexander, D.E.

    1993-08-01T23:59:59.000Z

    Recent work on enhanced interdiffusion rates during ion-beam mixing at elevated temperatures is reviewed. As discussed previously, expected increase in ion-beam mixing rates due to `radiation-enhanced diffusion` (RED), i.e. the free migration of isolated vacancy and interstitial defects, is well documented in single-crystal specimens in the range of 0.4 to 0.6 of absolute melting temperature. In contrast, the increase often observed at somewhat lower temperatures during ion-beam mixing of polycrystalline specimens is not well understood. However, sufficient evidence is available to show that this increase reflects intracascade enhancement of a thermally-activated process that also occurs without irradiation. Recent evidence is presented which suggests that this process is Diffusion-induced Grain-Boundary Migration (DIGM). An important complementary conclusion is that because ion-beam mixing in single-crystal specimens exhibits no significant temperature dependence below that of RED, models that invoke only irradiation-specific phenomena, e.g., cascade-overlap, thermal-spikes, or liquid-diffusion, and hence which predict no difference in mixing behavior between single- or poly-crystalline specimens, cannot account for the existing results.

  9. Focused ion beam micromilling and articles therefrom

    DOE Patents [OSTI]

    Lamartine, Bruce C. (Los Alamos, NM); Stutz, Roger A. (Los Alamos, NM)

    1998-01-01T23:59:59.000Z

    An ultrahigh vacuum focused ion beam micromilling apparatus and process are isclosed. Additionally, a durable data storage medium using the micromilling process is disclosed, the durable data storage medium capable of storing, e.g., digital or alphanumeric characters as well as graphical shapes or characters.

  10. Overview of Light-Ion Beam Therapy

    SciTech Connect (OSTI)

    Chu, William T.

    2006-03-16T23:59:59.000Z

    In 1930, Ernest Orlando Lawrence at the University of California at Berkeley invented the cyclotron. One of his students, M. Stanley Livingston, constructed a 13-cm diameter model that had all the features of early cyclotrons, accelerating protons to 80 keV using less than 1 kV on a semi-circular accelerating electrode, now called the ''dee''. Soon after, Lawrence constructed the first two-dee 27-Inch (69-cm) Cyclotron, which produced protons and deuterons of 4.8 MeV. In 1939, Lawrence constructed the 60-Inch (150-cm) Cyclotron, which accelerated deuterons to 19 MeV. Just before WWII, Lawrence designed a 184-inch cyclotron, but the war prevented the building of this machine. Immediately after the war ended, the Veksler-McMillan principle of phase stability was put forward, which enabled the transformation of conventional cyclotrons to successful synchrocyclotrons. When completed, the 184-Inch Synchrocyclotron produced 340-MeV protons. Following it, more modern synchrocyclotrons were built around the globe, and the synchrocyclotrons in Berkeley and Uppsala, together with the Harvard cyclotron, would perform pioneering work in treatment of human cancer using accelerated hadrons (protons and light ions). When the 184-Inch Synchrocyclotron was built, Lawrence asked Robert Wilson, one of his former graduate students, to look into the shielding requirements for of the new accelerator. Wilson soon realized that the 184-Inch would produce a copious number of protons and other light ions that had enough energy to penetrate human body, and could be used for treatment of deep-seated diseases. Realizing the advantages of delivering a larger dose in the Bragg peak when placed inside deep-seated tumors, he published in a medical journal a seminal paper on the rationale to use accelerated protons and light ions for treatment of human cancer. The precise dose localization provided by protons and light ions means lower doses to normal tissues adjacent to the treatment volume compared to those in conventional (photon) treatments. Wilson wrote his personal account of this pioneering work in 1997. In 1954 Cornelius Tobias and John Lawrence at the Radiation Laboratory (former E.O. Lawrence Berkeley National Laboratory) of the University of California, Berkeley performed the first therapeutic exposure of human patients to hadron (deuteron and helium ion) beams at the 184-Inch Synchrocyclotron. By 1984, or 30 years after the first proton treatment at Berkeley, programs of proton radiation treatments had opened at: University of Uppsala, Sweden, 1957; the Massachusetts General Hospital-Harvard Cyclotron Laboratory (MGH/HCL), USA, 1961; Dubna (1967), Moscow (1969) and St Petersburg (1975) in Russia; Chiba (1979) and Tsukuba (1983) in Japan; and Villigen, Switzerland, 1984. These centers used the accelerators originally constructed for nuclear physics research. The experience at these centers has confirmed the efficacy of protons and light ions in increasing the tumor dose relative to normal tissue dose, with significant improvements in local control and patient survival for several tumor sites. M.R. Raju reviewed the early clinical studies. In 1990, the Loma Linda University Medical Center in California heralded in the age of dedicated medical accelerators when it commissioned its proton therapy facility with a 250-MeV synchrotron. Since then there has been a relatively rapid increase in the number of hospital-based proton treatment centers around the world, and by 2006 there are more than a dozen commercially-built facilities in use, five new facilities under construction, and more in planning stages. In the 1950s larger synchrotrons were built in the GeV region at Brookhaven (3-GeV Cosmotron) and at Berkeley (6-GeV Bevatron), and today most of the world's largest accelerators are synchrotrons. With advances in accelerator design in the early 1970s, synchrotrons at Berkeley and Princeton accelerated ions with atomic numbers between 6 and 18, at energies that permitted the initiation of several biological studies. It is worth noting that when th

  11. Fuel Target Implosion in Ion beam Inertial Confinement Fusion

    E-Print Network [OSTI]

    Kawata, Shigeo

    2015-01-01T23:59:59.000Z

    The numerical results for the fuel target implosion are presented in order to clarify the target physics in ion beam inertial fusion. The numerical analyses are performed for a direct-driven ion beam target. In the paper the following issues are studied: the beam obliquely incidence on the target surface, the plasma effect on the beam-stopping power, the beam particle energy, the beam time duration, the target radius, the beam input energy and the non-uniformity effect on the fuel target performance. In this paper the beam ions are protons.

  12. Development of the Holifield Radioactive Ion Beam Facility

    SciTech Connect (OSTI)

    Tatum, B.A.

    1997-08-01T23:59:59.000Z

    The Holifield Radioactive Ion Beam Facility (HRIBF) construction project has been completed and the first radioactive ion beam has been successfully accelerated. The project, which began in 1992, has involved numerous facility modifications. The Oak Ridge Isochronous Cyclotron has been converted from an energy booster for heavy ion beams to a light ion accelerator with internal ion source. A target-ion source and mass analysis system have been commissioned as key components of the facility`s radioactive ion beam injector to the 25MV tandem electrostatic accelerator. Beam transport lines have been completed, and new diagnostics for very low intensity beams have been developed. Work continues on a unified control system. Development of research quality radioactive beams for the nuclear structure and nuclear astrophysics communities continues. This paper details facility development to date.

  13. Electron beam diagnostic for space charge measurement of an ion beam

    SciTech Connect (OSTI)

    Roy, Prabir K.; Yu, Simon S.; Henestroza, Enrique; Eylon, Shmuel; Shuman, Derek B.; Ludvig, Jozsef; Bieniosek, Frank M.; Waldron, William L.; Greenway, Wayne G.; Vanecek, David L.; Hannink, Ryan; Amezcua, Monserrat

    2004-09-25T23:59:59.000Z

    A non-perturbing electron beam diagnostic system for measuring the charge distribution of an ion beam is developed for Heavy Ion Fusion (HIF) beam physics studies. Conventional diagnostics require temporary insertion of sensors into the beam, but such diagnostics stop the beam, or significantly alter its properties. In this diagnostic a low energy, low current electron beam is swept transversely across the ion beam; the measured electron beam deflection is used to infer the charge density profile of the ion beam. The initial application of this diagnostic is to the Neutralized Transport Experiment (NTX), which is exploring the physics of space-charge-dominated beam focusing onto a small spot using a neutralizing plasma. Design and development of this diagnostic and performance with the NTX ion beamline is presented.

  14. Characterization of ionic liquid ion sources for focused ion beam applications

    E-Print Network [OSTI]

    Perez Martinez, Carla S. (Carla Sofia)

    2013-01-01T23:59:59.000Z

    In the Focused Ion Beam (FIB) technique, a beam of ions is reduced to nanometer dimensions using dedicated optics and directed to a substrate for patterning. This technique is widely used in micro- and nanofabrication for ...

  15. ECR plasma source for heavy ion beam charge neutralization

    E-Print Network [OSTI]

    Gilson, Erik

    plasmas are being considered as a medium for charge neutralizing heavy ion beams in order to focus beyond resonance. Keywords: Plasma focus; RF plasma; Beam charge neutralization 1. INTRODUCTION A possible heavyECR plasma source for heavy ion beam charge neutralization PHILIP C. EFTHIMION,1 ERIK GILSON,1

  16. Development of a focused ion beam micromachining system

    SciTech Connect (OSTI)

    Pellerin, J.G.; Griffis, D.; Russell, P.E.

    1988-12-01T23:59:59.000Z

    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.

  17. Scanning-helium-ion-beam lithography with hydrogen silsesquioxane resist

    E-Print Network [OSTI]

    Winston, Donald

    A scanning-helium-ion-beam microscope is now commercially available. This microscope can be used to perform lithography similar to, but of potentially higher resolution than, scanning electron-beam lithography. This article ...

  18. Nanostructure fabrication by electron and ion beam patterning of nanoparticles

    E-Print Network [OSTI]

    Kong, David Sun, 1979-

    2004-01-01T23:59:59.000Z

    Two modes of energetic beam-mediated fabrication have been investigated, namely focused ion beam (FIB) direct-writing of nanoparticles, and a technique for electrostatically patterning ionized inorganic nanoparticles, ...

  19. Structural Modification of Nanocrystalline Ceria by Ion Beams...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    nanoscale. Citation: Zhang Y, PD Edmondson, T Varga, SJ Moll, F Namavar, C Lan, and WJ Weber.2011."Structural Modification of Nanocrystalline Ceria by Ion Beams."Physical...

  20. alkali ion beams: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    DT capsule a heavy-ion beam. and is presented in Fig.1. unknown authors 4 METHOD FOR EFFICIENCY AND TIME RESPONSE MEASUREMENT ON DIVERSE TARGET ION SOURCES WITH STABLE ALKALI...

  1. DEVELOPMENT OF EMITTANCE ANALYSIS SOFTWARE FOR ION BEAM CHARACTERIZATION

    SciTech Connect (OSTI)

    Padilla, M. J.; Liu, Y.

    2007-01-01T23:59:59.000Z

    Transverse beam emittance is a crucial property of charged particle beams that describes their angular and spatial spread. It is a fi gure of merit frequently used to determine the quality of ion beams, the compatibility of an ion beam with a given beam transport system, and the ability to suppress neighboring isotopes at on-line mass separator facilities. Generally a high quality beam is characterized by a small emittance. In order to determine and improve the quality of ion beams used at the Holifi eld Radioactive Ion beam Facility (HRIBF) for nuclear physics and nuclear astrophysics research, the emittances of the ion beams are measured at the off-line Ion Source Test Facilities. In this project, emittance analysis software was developed to perform various data processing tasks for noise reduction, to evaluate root-mean-square emittance, Twiss parameters, and area emittance of different beam fractions. The software also provides 2D and 3D graphical views of the emittance data, beam profi les, emittance contours, and RMS. Noise exclusion is essential for accurate determination of beam emittance values. A Self-Consistent, Unbiased Elliptical Exclusion (SCUBEEx) method is employed. Numerical data analysis techniques such as interpolation and nonlinear fi tting are also incorporated into the software. The software will provide a simplifi ed, fast tool for comprehensive emittance analysis. The main functions of the software package have been completed. In preliminary tests with experimental emittance data, the analysis results using the software were shown to be accurate.

  2. Fluctuation of an ion beam extracted from an AC filament driven Bernas-type ion source

    SciTech Connect (OSTI)

    Miyamoto, N., E-mail: nmiyamot@mail.doshisha.ac.jp; Okajima, Y.; Wada, M. [Graduate School of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321 (Japan)] [Graduate School of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321 (Japan)

    2014-02-15T23:59:59.000Z

    Argon ion beam fluctuation from an AC filament driven Bernas-type ion source is observed. The ion beam was measured by an 8 measurement elements beam profile monitor. The amplitude of the beam current fluctuation stayed in the same level from 100 Hz to 1 kHz of the filament heating frequency. The beam current fluctuation frequency measured by the beam profile monitor was equal to the frequency of the AC filament operation. The fluctuation amplitudes of the beam current by AC operation were less than 7% and were in the same level of the DC operation.

  3. Sandia National Laboratories: ion beam assisted deposition

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    grid relies on power transmission from the production source-be it a coal-fired plant, solar array, or wind farm-to the consumer. Long-distance transmission results in...

  4. Improvement of Ion-Beam Energy Resolution in a Solenoid-based Radioactive Nuclear Beam Facility

    E-Print Network [OSTI]

    Becchetti, Fred

    Improvement of Ion-Beam Energy Resolution in a Solenoid-based Radioactive Nuclear Beam Facility of Philosophy (Nuclear Engineering and Radiological Sciences) in The University of Michigan 2010 Doctoral

  5. Production of multiply charged ion beams from solid substances with the mVINIS ion source

    SciTech Connect (OSTI)

    Draganic, I.; Dobrosavljevic, A.; Nedeljkovic, T.; Siljegovic, M. [Laboratory of Physics, Vinca Institute of Nuclear Sciences, P.O. Box. 522, 11000 Belgrade (Serbia and Montenegro)

    2006-03-15T23:59:59.000Z

    The mVINIS ion source has enabled us to obtain multiply charged ion beams from gases as well as from solid materials. The solid substance ion beams were produced by using two techniques: (a) the evaporation of metals by using the inlet system based on a minioven and (b) the metal-ions-from-volatile-compounds method (MIVOC) by using the modified gas inlet system. Great efforts were made in the production of high current stable ion beams of solids with relatively high melting points (over 1000 deg. C). The B{sup 3+} ion-beam current of over 300 {mu}A was one of the most intensive beams extracted until now. The obtained multiply charged ion-beam spectra of solid substances (B, Fe, and Zn) are presented as well as some of the corresponding experimental results achieved during the modification of polymers, carbon materials, and fullerenes.

  6. PIC MODELING: Measuring Ion Beam Current Density in the

    E-Print Network [OSTI]

    Kaganovich, Igor

    ;Collaborators: R. C. Davidson, P. C. Efthimion, E. P. Gilson (PPPL) S. S. Yu, P. K. Roy, F. M. Bieniosek, W. L) Converging ion beam Chamber Wall #12;3The Neutralized Transport Experiment was a success 400 kV Marx & Fire Injector #12;5Neutralized drift compression modeled with a particle-in-cell code (LSP) K+ ion beam

  7. Measurements of Beam Ion Loss from the Compact Helical System

    SciTech Connect (OSTI)

    D. S. Darrow, M. Isobe, Takashi Kondo, M. Sasao, and the CHS Group National Institute for Fusion Science, Toki, Gifu, Japan

    2010-02-03T23:59:59.000Z

    Beam ion loss from the Compact Helical System (CHS) has been measured with a scintillator-type probe. The total loss to the probe, and the pitch angle and gyroradius distributions of that loss, have been measured as various plasma parameters were scanned. Three classes of beam ion loss were observed at the probe position: passing ions with pitch angles within 10o of those of transition orbits, ions on transition orbits, and ions on trapped orbits, typically 15o or more from transition orbits. Some orbit calculations in this geometry have been performed in order to understand the characteristics of the loss. Simulation of the detector signal based upon the following of orbits from realistic beam deposition profiles is not able to reproduce the pitch angle distribution of the losses measured. Consequently it is inferred that internal plasma processes, whether magnetohydrodynamic modes, radial electric fields, or plasma turbulence, move previously confined beam ions to transition orbits, resulting in their loss.

  8. VACUUM PRESSURE RISE WITH INTENSE ION BEAMS IN RHIC.

    SciTech Connect (OSTI)

    FISCHER,W.; BAI,M.; BRENNAN,J.M.; BLASKIEWICZ,M.; CAMERON,P.; HSEUH,H.C.; HUANG,H.; MACKAY,W.; ROSER,T.; SATOGATA,T.; SMART,L.A.; TRBOJEVIC,D.; ZHANG,S.Y.

    2002-06-02T23:59:59.000Z

    When RHIC is filled with bunches of intense ion beams a pressure rise is observed. The pressure rise exceeds the acceptable limit for operation with the design intensities. Observations of events leading to a pressure rise are summarized. Relevant parameters include ion species, charge per bunch, bunch spacing, and the location in the ring. Effects that contribute to a pressure rise are discussed, including beam gas ionization and ion desorption, loss-induced gas desorption, and electron desorption from electron clouds.

  9. Nonlinear plasma waves excitation by intense ion beams in background plasma

    E-Print Network [OSTI]

    Kaganovich, Igor

    describe the plasma perturbations well.5 Here, we focus on the general case where the plasma density hasNonlinear plasma waves excitation by intense ion beams in background plasma Igor D. Kaganovich, Edward A. Startsev, and Ronald C. Davidson Plasma Physics Laboratory, Princeton University, Princeton

  10. Method and apparatus for efficient photodetachment and purification of negative ion beams

    DOE Patents [OSTI]

    Beene, James R. (Oak Ridge, TN) [Oak Ridge, TN; Liu, Yuan (Knoxville, TN) [Knoxville, TN; Havener, Charles C. (Knoxville, TN) [Knoxville, TN

    2008-02-26T23:59:59.000Z

    Methods and apparatus are described for efficient photodetachment and purification of negative ion beams. A method of purifying an ion beam includes: inputting the ion beam into a gas-filled multipole ion guide, the ion beam including a plurality of ions; increasing a laser-ion interaction time by collisional cooling the plurality of ions using the gas-filled multipole ion guide, the plurality of ions including at least one contaminant; and suppressing the at least one contaminant by selectively removing the at least one contaminant from the ion beam by electron photodetaching at least a portion of the at least one contaminant using a laser beam.

  11. Status of Beta Beam R&D: Radioactive ion production

    E-Print Network [OSTI]

    McDonald, Kirk

    Status of Beta Beam R&D: Radioactive ion production O b h lf f EURISOL DS*/ISOLDE CERN Etam NOAH Infrastructure Action Structuring the European Research Area" g , y , Status of BetaBeam R&D AHIPA09 etam Status of BetaBeam R&D AHIPA09 etam.noah@esss.se #12;Introduction to betabeams Beta-beam proposal

  12. Shielding analysis for a heavy ion beam chamber with plasma channels for ion transport

    E-Print Network [OSTI]

    Sawan, M.E.; Peterson, R.R.; Yu, S.

    2000-01-01T23:59:59.000Z

    Analysis for a Heavy Ion Beam Chamber with Plasma Channelsthe target chamber wall, an adiabatic lens to focus the ionchamber that utilizes pre-formed plasma channels for heavy ion

  13. Ion beam collimating grid to reduce added defects

    DOE Patents [OSTI]

    Lindquist, Walter B. (Oakland, CA); Kearney, Patrick A. (Livermore, CA)

    2003-01-01T23:59:59.000Z

    A collimating grid for an ion source located after the exit grid. The collimating grid collimates the ion beamlets and disallows beam spread and limits the beam divergence during transients and steady state operation. The additional exit or collimating grid prevents beam divergence during turn-on and turn-off and prevents ions from hitting the periphery of the target where there is re-deposited material or from missing the target and hitting the wall of the vessel where there is deposited material, thereby preventing defects from being deposited on a substrate to be coated. Thus, the addition of a collimating grid to an ion source ensures that the ion beam will hit and be confined to a specific target area.

  14. The Heavy Ion Fusion Science Virtual National Laboratory Physics of neutralization of

    E-Print Network [OSTI]

    Kaganovich, Igor

    everywhere (c). P.K. Roy et al, NIMPR A 544, 225 (2005). #12;#5 Radial Compression requires degreeV K+ ion beam: (a) without plasma (b) with plasma. NTX experiments, P.K. Roy et al, NIMPR. A 544, 225. Startsev, A. B. Sefkow Princeton Plasma Physics Laboratory E. P. Lee, A. Friedman Lawrence Berkeley

  15. Note: High density pulsed molecular beam for cold ion chemistry

    SciTech Connect (OSTI)

    Kokish, M. G.; Rajagopal, V.; Marler, J. P.; Odom, B. C., E-mail: b-odom@northwestern.edu [Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208 (United States)

    2014-08-15T23:59:59.000Z

    A recent expansion of cold and ultracold molecule applications has led to renewed focus on molecular species preparation under ultrahigh vacuum conditions. Meanwhile, molecular beams have been used to study gas phase chemical reactions for decades. In this paper, we describe an apparatus that uses pulsed molecular beam technology to achieve high local gas densities, leading to faster reaction rates with cold trapped ions. We characterize the beam's spatial profile using the trapped ions themselves. This apparatus could be used for preparation of molecular species by reactions requiring excitation of trapped ion precursors to states with short lifetimes or for obtaining a high reaction rate with minimal increase of background chamber pressure.

  16. Plasma ion sources and ion beam technology in microfabrications

    E-Print Network [OSTI]

    Ji, Lili

    2007-01-01T23:59:59.000Z

    in the right chamber (ion chamber) are confined in their ownwatts and that on the ion chamber is 50 watts. A permanent-column and the ion source chamber. The simulation is

  17. EBIT - Electronic Beam Ion Trap: N Divison experimental physics annual report 1995

    SciTech Connect (OSTI)

    Schneider, D. [ed.

    1996-10-01T23:59:59.000Z

    The multi-faceted research effort of the EBIT (Electron Beam Ion Trap) program in N-Division of the Physics and Space Technology Department at Lawrence Livermore National Laboratory (LLNL) continues to contribute significant results to the physical sciences from studies with low energy very highly charged heavy ions. The EBIT program attracts a number of collaborators from the US and abroad for the different projects. The collaborations are partly carried out through participating graduate students demonstrating the excellent educational capabilities at the LLNL EBIT facilities. Moreover, participants from Historically Black Colleges and Universities are engaged in the EBIT project. This report describes EBIT work for 1995 in atomic structure measurements and radiative transition probabilities, spectral diagnostics for laboratory and astrophysical plasmas, ion/surface interaction studies, electron-ion interactions studies, retrap and ion collisions, and instrumental development.

  18. anaconda ion beam: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Ion beam CiteSeer Summary: Fast ignition is a method to decrease the energy of a fusion driver 1. At first the matter becomes compressed to high densities due to the...

  19. advanced ion beam: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Ion beam CiteSeer Summary: Fast ignition is a method to decrease the energy of a fusion driver 1. At first the matter becomes compressed to high densities due to the...

  20. Etching of Graphene Devices with a Helium Ion Beam

    E-Print Network [OSTI]

    Baugher, Britton William Herb

    We report on the etching of graphene devices with a helium ion beam, including in situ electrical measurement during lithography. The etching process can be used to nanostructure and electrically isolate different regions ...

  1. The beam diagnostic instruments in Beijing radioactive ion-beam facilities isotope separator on-line

    SciTech Connect (OSTI)

    Ma, Y., E-mail: yjma@ciae.ac.cn; Cui, B.; Ma, R.; Tang, B.; Chen, L.; Huang, Q.; Jiang, W. [China Institute of Atomic Energy, Beijing 102413 (China)] [China Institute of Atomic Energy, Beijing 102413 (China)

    2014-02-15T23:59:59.000Z

    The beam diagnostic instruments for Beijing Radioactive Ion-beam Facilities Isotope Separator On-Line are introduced [B. Q. Cui, Z. H. Peng, Y. J. Ma, R. G. Ma, B. Tang, T. Zhang, and W. S. Jiang, Nucl. Instrum. Methods 266, 4113 (2008); T. J. Zhang, X. L. Guan, and B. Q. Cui, in Proceedings of APAC 2004, Gyeongju, Korea, 2004, http://www.jacow.org , p. 267]. For low intensity ion beam [30–300 keV/1 pA–10 ?A], the beam profile monitor, the emittance measurement unit, and the analyzing slit will be installed. For the primary proton beam [100 MeV/200 ?A], the beam profile scanner will be installed. For identification of the nuclide, a beam identification unit will be installed. The details of prototype of the beam diagnostic units and some experiment results will be described in this article.

  2. Dual ion beam assisted deposition of biaxially textured template layers

    DOE Patents [OSTI]

    Groves, James R.; Arendt, Paul N.; Hammond, Robert H.

    2005-05-31T23:59:59.000Z

    The present invention is directed towards a process and apparatus for epitaxial deposition of a material, e.g., a layer of MgO, onto a substrate such as a flexible metal substrate, using dual ion beams for the ion beam assisted deposition whereby thick layers can be deposited without degradation of the desired properties by the material. The ability to deposit thicker layers without loss of properties provides a significantly broader deposition window for the process.

  3. The ReA electron-beam ion trap charge breeder for reacceleration of rare isotopes

    SciTech Connect (OSTI)

    Lapierre, A.; Schwarz, S.; Kittimanapun, K.; Fogleman, J.; Krause, S.; Nash, S.; Rencsok, R.; Tobos, L.; Perdikakis, G.; Portillo, M.; Rodriguez, J. A.; Wittmer, W.; Wu, X.; Bollen, G.; Leitner, D.; Syphers, M. [National Superconducting Cyclotron Laboratory (NSCL), Michigan State University (MSU), 640 South Shaw Lane, East Lansing, MI 48824 (United States); Collaboration: ReA Team

    2013-04-19T23:59:59.000Z

    ReA is a post-accelerator at the National Superconducting Cyclotron Laboratory at Michigan State University. ReA is designed to reaccelerate rare isotopes to energies of a few MeV/u following production by projectile fragmentation and thermalization in a gas cell. The facility consists of four main components: an electron-beam ion trap (EBIT) charge breeder, an achromatic charge-over-mass (Q/A) separator, a radio-frequency quadrupole accelerator, and a superconducting radio-frequency linear accelerator. The EBIT charge breeder was specifically designed to efficiently capture continuous beams of singly charged ions injected at low energy (<60 keV), charge breed in less than 50 ms, and extract highly charged ions to the Q/A separator for charge-state selection and reacceleration through the accelerator structures. The use of highly charged ions to reach high beam energies is a key aspect that makes ReA a compact and cost-efficient post-accelerator. The EBIT is characterized by a high-current electron gun, a long multi-electrode trap structure and a dual magnet to provide both the high electron-beam current density necessary for fast charge breeding of short-lived isotopes as well as the high capture probability of injected beams. This paper presents an overview and the status of the ReA EBIT, which has extracted for reacceleration tests stable {sup 20}Ne{sup 8+} ion beams produced from injected gas and more recently {sup 39}K{sup 16+} beams by injecting stable {sup 39,41}K{sup +} ions from an external ion source.

  4. Studies of Impurity Deposition/Implantation in JET Divertor Tiles using SIMS and Ion Beam Techniques

    E-Print Network [OSTI]

    Studies of Impurity Deposition/Implantation in JET Divertor Tiles using SIMS and Ion Beam Techniques

  5. Solenoidal Fields for Ion Beam Transport and Focusing

    SciTech Connect (OSTI)

    Lee, Edward P.; Leitner, Matthaeus

    2007-11-01T23:59:59.000Z

    In this report we calculate time-independent fields of solenoidal magnets that are suitable for ion beam transport and focusing. There are many excellent Electricity and Magnetism textbooks that present the formalism for magnetic field calculations and apply it to simple geometries [1-1], but they do not include enough relevant detail to be used for designing a charged particle transport system. This requires accurate estimates of fringe field aberrations, misaligned and tilted fields, peak fields in wire coils and iron, external fields, and more. Specialized books on magnet design, technology, and numerical computations [1-2] provide such information, and some of that is presented here. The AIP Conference Proceedings of the US Particle Accelerator Schools [1-3] contain extensive discussions of design and technology of magnets for ion beams - except for solenoids. This lack may be due to the fact that solenoids have been used primarily to transport and focus particles of relatively low momenta, e.g. electrons of less than 50 MeV and protons or H- of less than 1.0 MeV, although this situation may be changing with the commercial availability of superconducting solenoids with up to 20T bore field [1-4]. Internal reports from federal laboratories and industry treat solenoid design in detail for specific applications. The present report is intended to be a resource for the design of ion beam drivers for Inertial Fusion Energy [1-5] and Warm Dense Matter experiments [1-6], although it should also be useful for a broader range of applications. The field produced by specified currents and material magnetization can always be evaluated by solving Maxwell's equations numerically, but it is also desirable to have reasonably accurate, simple formulas for conceptual system design and fast-running beam dynamics codes, as well as for general understanding. Most of this report is devoted to such formulas, but an introduction to the Tosca{copyright} code [1-7] and some numerical results obtained with it are also presented. Details of design, fabrication, installation, and operation of magnet systems are not included; here we are concerned with calculations that precede or supplement detailed design. Mathematical derivations are presented with only a moderate number of steps. While there is no claim of originality, except for various numerical approximations and a conceptual induction module design in section 20, many of the results and discussions are not readily available elsewhere. Our primary topic is axisymmetric solenoidal systems with no magnetic materials. These simplifying features allow useful analytical calculations, which occupy sections 2-13. Deviations from axisymmetry are considered in sections 14, 15, 21, 22, and 23 and the effects of magnetic materials are treated in sections 16-20. Since magnetic aberrations are mixed with geometric aberrations in computing ion orbits, section 22 on the ion equations of motion in an arbitrary field is included.

  6. An ion source module for the Beijing Radioactive Ion-beam Facility

    SciTech Connect (OSTI)

    Cui, B., E-mail: cui@ciae.ac.cn; Huang, Q.; Tang, B.; Ma, R.; Chen, L.; Ma, Y. [China Institute of Atomic Energy, Beijing (China)] [China Institute of Atomic Energy, Beijing (China)

    2014-02-15T23:59:59.000Z

    An ion source module is developed for Beijing Radioactive Ion-beam Facility. The ion source module is designed to meet the requirements of remote handling. The connection and disconnection of the electricity, cooling and vacuum between the module and peripheral units can be executed without on-site manual work. The primary test of the target ion source has been carried out and a Li{sup +} beam has been extracted. Details of the ion source module and its primary test results are described.

  7. The Heavy Ion Fusion Virtual National Laboratory The Heavy Ion Path to Fusion Energy

    E-Print Network [OSTI]

    , describes R&D needs for heavy-ion accelerator, target and chamber R&D. 44 pages. Defines goals and criteria tasks) - ion accelerator technologies - chamber and maintenance technologies - pulsed power technologiesThe Heavy Ion Fusion Virtual National Laboratory The Heavy Ion Path to Fusion Energy Grant Logan

  8. A compact, versatile low-energy electron beam ion source

    SciTech Connect (OSTI)

    Zschornack, G., E-mail: g.zschornack@hzdr.de [Department of Physics, Dresden University of Technology, 01062 Dresden, Germany and Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden (Germany); König, J.; Schmidt, M.; Thorn, A. [DREEBIT GmbH, 01109 Dresden (Germany)] [DREEBIT GmbH, 01109 Dresden (Germany)

    2014-02-15T23:59:59.000Z

    A new compact Electron Beam Ion Source, the Dresden EBIT-LE, is introduced as an ion source working at low electron beam energies. The EBIT-LE operates at an electron energy ranging from 100 eV to some keV and can easily be modified to an EBIT also working at higher electron beam energies of up to 15 keV. We show that, depending on the electron beam energy, electron beam currents from a few mA in the low-energy regime up to about 40 mA in the high-energy regime are possible. Technical solutions as well as first experimental results of the EBIT-LE are presented. In ion extraction experiments, a stable production of low and intermediate charged ions at electron beam energies below 2 keV is demonstrated. Furthermore, X-ray spectroscopy measurements confirm the possibility of using the machine as a source of X-rays from ions excited at low electron energies.

  9. IMAGING WITH A MULTIPLANE MULTIWIRE PROPORTIONAL CHAMBER USING HEAVY ION BEAMS

    E-Print Network [OSTI]

    Chu, W.T.

    2010-01-01T23:59:59.000Z

    1. When the he^vy ions penetrate the chamber, the resultingMULTIWIRE PROPORTIONAL CHAMBER USING HEAVY-ION BEAMS* U. T.Ion Beam Studies and Imaging with a Nultiplane Multiwire Proportional Chamber,"

  10. Linac4 low energy beam measurements with negative hydrogen ions

    SciTech Connect (OSTI)

    Scrivens, R., E-mail: richard.scrivens@cern.ch; Bellodi, G.; Crettiez, O.; Dimov, V.; Gerard, D.; Granemann Souza, E.; Guida, R.; Hansen, J.; Lallement, J.-B.; Lettry, J.; Lombardi, A.; Midttun, Ø.; Pasquino, C.; Raich, U.; Riffaud, B.; Roncarolo, F.; Valerio-Lizarraga, C. A.; Wallner, J.; Yarmohammadi Satri, M.; Zickler, T. [CERN, 1211 Geneva 23 (Switzerland)] [CERN, 1211 Geneva 23 (Switzerland)

    2014-02-15T23:59:59.000Z

    Linac4, a 160 MeV normal-conducting H{sup ?} linear accelerator, is the first step in the upgrade of the beam intensity available from the LHC proton injectors at CERN. The Linac4 Low Energy Beam Transport (LEBT) line from the pulsed 2 MHz RF driven ion source, to the 352 MHz RFQ (Radiofrequency Quadrupole) has been built and installed at a test stand, and has been used to transport and match to the RFQ a pulsed 14 mA H{sup ?} beam at 45 keV. A temporary slit-and-grid emittance measurement system has been put in place to characterize the beam delivered to the RFQ. In this paper a description of the LEBT and its beam diagnostics is given, and the results of beam emittance measurements and beam transmission measurements through the RFQ are compared with the expectation from simulations.

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

    SciTech Connect (OSTI)

    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.

    2008-08-01T23:59:59.000Z

    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.

  12. Feasibility study of a laser ion source for primary ion injection into the Relativistic Heavy Ion Collider electron beam ion sourcea...

    E-Print Network [OSTI]

    chamber to be able to change ion species on a pulse by pulse basis. The optimal plasma drift length variesFeasibility study of a laser ion source for primary ion injection into the Relativistic Heavy Ion Collider electron beam ion sourcea... Takeshi Kanesue Department of Applied Quantum Physics and Nuclear

  13. Fusion Induced by Radioactive Ion Beams

    E-Print Network [OSTI]

    J. F. Liang; C. Signorini

    2005-04-26T23:59:59.000Z

    The use of radioactive beams opens a new frontier for fusion studies. The coupling to the continuum can be explored with very loosely bound nuclei. Experiments were performed with beams of nuclei at or near the proton and neutron drip-lines to measure fusion and associated reactions in the vicinity of the Coulomb barrier. In addition, the fusion yield is predicted to be enhanced in reactions involving very neutron-rich unstable nuclei. Experimental measurements were carried out to investigate if it is feasible to use such beams to produce new heavy elements. The current status of these experimental activities is given in this review.

  14. Ion beam driven ion-acoustic waves in a plasma cylinder with negatively charged dust grains

    SciTech Connect (OSTI)

    Sharma, Suresh C.; Walia, Ritu [Department of Physics, Maharaja Agrasen Institute of Technology, PSP Area Plot No.-1, Sector-22, Rohini, Delhi 110 086 (India); Sharma, Kavita [Department of Physics, Bhagwan Parshuram Institute of Technology, Sector-17, Rohini, New Delhi 110 089 (India)

    2012-07-15T23:59:59.000Z

    An ion beam propagating through a magnetized potassium plasma cylinder having negatively charged dust grains drives electrostatic ion-acoustic waves to instability via Cerenkov interaction. The phase velocity of sound wave increases with the relative density of negatively charged dust grains. The unstable wave frequencies and the growth rate increase, with the relative density of negatively charged dust grains. The growth rate of the unstable mode scales as one-third power of the beam density. The real part of frequency of the unstable mode increases with the beam energy and scales as almost the one-half power of the beam energy.

  15. Production of N[sup +] ions from a multicusp ion beam apparatus

    DOE Patents [OSTI]

    Kango Leung; Kunkel, W.B.; Walther, S.R.

    1993-03-30T23:59:59.000Z

    A method of generating a high purity (at least 98%) N[sup +] ion beam using a multicusp ion source having a chamber formed by a cylindrical chamber wall surrounded by a plurality of magnets, a filament centrally disposed in said chamber, a plasma electrode having an extraction orifice at one end of the chamber, a magnetic filter having two parallel magnets spaced from said plasma electrode and dividing the chamber into arc discharge and extraction regions. The method includes ionizing nitrogen gas in the arc discharge region of the chamber, maintaining the chamber wall at a positive voltage relative to the filament and at a magnitude for an optimum percentage of N[sup +] ions in the extracted ion beams, disposing a hot liner within the chamber and near the chamber wall to limit recombination of N[sup +] ions into the N[sub 2][sup +] ions, spacing the magnets of the magnetic filter from each other for optimum percentage of N[sup 3] ions in the extracted ion beams, and maintaining a relatively low pressure downstream of the extraction orifice and of a magnitude (preferably within the range of 3-8[times]10[sup [minus]4] torr) for an optimum percentage of N[sup +] ions in the extracted ion beam.

  16. Production of N.sup.+ ions from a multicusp ion beam apparatus

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA); Kunkel, Wulf B. (Berkeley, CA); Walther, Steven R. (Salem, MA)

    1993-01-01T23:59:59.000Z

    A method of generating a high purity (at least 98%) N.sup.+ ion beam using a multicusp ion source (10) having a chamber (11) formed by a cylindrical chamber wall (12) surrounded by a plurality of magnets (13), a filament (57) centrally disposed in said chamber, a plasma electrode (36) having an extraction orifice (41) at one end of the chamber, a magnetic filter having two parallel magnets (21, 22) spaced from said plasma electrode (36) and dividing the chamber (11) into arc discharge and extraction regions. The method includes ionizing nitrogen gas in the arc discharge region of the chamber (11), maintaining the chamber wall (12) at a positive voltage relative to the filament (57) and at a magnitude for an optimum percentage of N.sup.+ ions in the extracted ion beams, disposing a hot liner (45) within the chamber and near the chamber wall (12) to limit recombination of N.sup.+ ions into the N.sub.2.sup.+ ions, spacing the magnets (21, 22) of the magnetic filter from each other for optimum percentage of N.sup.3 ions in the extracted ion beams, and maintaining a relatively low pressure downstream of the extraction orifice and of a magnitude (preferably within the range of 3-8.times.10.sup.-4 torr) for an optimum percentage of N.sup.+ ions in the extracted ion beam.

  17. First storage of ion beams in the Double Electrostatic Ion-Ring Experiment: DESIREE

    SciTech Connect (OSTI)

    Schmidt, H. T.; Thomas, R. D.; Gatchell, M.; Rosen, S.; Reinhed, P.; Loefgren, P.; Braennholm, L.; Blom, M.; Bjoerkhage, M.; Baeckstroem, E.; Alexander, J. D.; Leontein, S.; Zettergren, H.; Liljeby, L.; Kaellberg, A.; Simonsson, A.; Hellberg, F.; Mannervik, S.; Larsson, M.; Geppert, W. D. [Department of Physics, Stockholm University, SE-10691 Stockholm (Sweden); and others

    2013-05-15T23:59:59.000Z

    We report on the first storage of ion beams in the Double ElectroStatic Ion Ring ExpEriment, DESIREE, at Stockholm University. We have produced beams of atomic carbon anions and small carbon anion molecules (C{sub n}{sup -}, n= 1, 2, 3, 4) in a sputter ion source. The ion beams were accelerated to 10 keV kinetic energy and stored in an electrostatic ion storage ring enclosed in a vacuum chamber at 13 K. For 10 keV C{sub 2}{sup -} molecular anions we measure the residual-gas limited beam storage lifetime to be 448 s {+-} 18 s with two independent detector systems. Using the measured storage lifetimes we estimate that the residual gas pressure is in the 10{sup -14} mbar range. When high current ion beams are injected, the number of stored particles does not follow a single exponential decay law as would be expected for stored particles lost solely due to electron detachment in collision with the residual-gas. Instead, we observe a faster initial decay rate, which we ascribe to the effect of the space charge of the ion beam on the storage capacity.

  18. Sandia National Laboratories: molecularly engineered ion exchanger

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ion exchanger ECIS and UOP (a Honewell Company): CSTs Clean Radioactive Waste in Fukushima and Worldwide On February 14, 2013, in Energy, Materials Science, Nuclear Energy,...

  19. Sandia National Laboratories: lithium-ion battery

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ion battery Electric Car Challenge Sparks Students' STEM Interest On January 9, 2015, in Energy, Energy Storage, News, News & Events, Partnership, Transportation Energy Aspiring...

  20. Plasma and Ion Beam Injection into an FRC

    SciTech Connect (OSTI)

    Anderson, M.; Bystritskii, V.; Garate, E.; Rostoker, N.; Song, Y.; Drie, A. van [Department of Physics and Astronomy, University of California at Irvine, CA, 92697 (United States); Binderbauer, M. [Tri Alpha Energy Inc., Foothill Ranch, CA, 92610 (United States); Isakov, I. [Institute of High Voltage Technology, Tomsk, 634050 (Russian Federation)

    2005-10-15T23:59:59.000Z

    Experiments on the transverse injection of intense (5-20 A/cm{sup 2}), wide cross-section (10-cm), neutralized, {approx}100-eV H{sup +} plasma and 100-keV H{sup +} ion beams into a preformed B-field reversed configuration (FRC) are described. The FRC background plasma temperature was {approx}5 eV with densities of {approx}10{sup 13} cm{sup -3}. In contrast to earlier experiments, the background plasma was generated by separate plasma gun arrays. For the startup of the FRC, a betatron-type 'slow' coaxial source was used. Injection of the plasma beam into the preformed FRC resulted in a 30-40% increase of the FRC lifetime and the amplitude of the reversed magnetic field. As for the ion beam injection experiment into the preformed FRC, there was evidence of beam capture within the configuration.

  1. Slit disk for modified faraday cup diagnostic for determining power density of electron and ion beams

    DOE Patents [OSTI]

    Teruya, Alan T. (Livermore, CA); Elmer; John W. (Danville, CA); Palmer, Todd A. (State College, PA)

    2011-03-08T23:59:59.000Z

    A diagnostic system for characterization of an electron beam or an ion beam includes an electrical conducting disk of refractory material having a circumference, a center, and a Faraday cup assembly positioned to receive the electron beam or ion beam. At least one slit in the disk provides diagnostic characterization of the electron beam or ion beam. The at least one slit is located between the circumference and the center of the disk and includes a radial portion that is in radial alignment with the center and a portion that deviates from radial alignment with the center. The electron beam or ion beam is directed onto the disk and translated to the at least one slit wherein the electron beam or ion beam enters the at least one slit for providing diagnostic characterization of the electron beam or ion beam.

  2. ELECTRON BEAM ION SOURCE PREINJECTOR PROJECT (EBIS) CONCEPTUAL DESIGN REPORT.

    SciTech Connect (OSTI)

    ALESSI, J.; BARTON, D.; BEEBE, E.; GASSNER, D.; ET AL.

    2005-02-28T23:59:59.000Z

    This report describes a new heavy ion pre-injector for the Relativistic Heavy Ion Collider (RHIC) based on a high charge state Electron Beam Ion Source (EBIS), a Radio Frequency Quadrupole (RFQ) accelerator, and a short Linac. The highly successful development of an EBIS at BNL now makes it possible to replace the present pre-injector that is based on an electrostatic Tandem with a reliable, low maintenance Linac-based pre-injector. Linac-based pre-injectors are presently used at most accelerator and collider facilities with the exception of RHIC, where the required gold beam intensities could only be met with a Tandem until the recent EBIS development. EBIS produces high charge state ions directly, eliminating the need for the two stripping foils presently used with the Tandem. Unstable stripping efficiencies of these foils are a significant source of luminosity degradation in RHIC. The high reliability and flexibility of the new Linac-based pre-injector will lead to increased integrated luminosity at RHIC and is an essential component for the long-term success of the RHIC facility. This new pre-injector, based on an EBIS, also has the potential for significant future intensity increases and can produce heavy ion beams of all species including uranium beams and, as part of a future upgrade, might also be used to produce polarized {sup 3}He beams. These capabilities will be critical to the future luminosity upgrades and electron-ion collisions in RHIC. The new RFQ and Linac that are used to accelerate beams from the EBIS to an energy sufficient for injection into the Booster are both very similar to existing devices already in operation at other facilities. Injection into the Booster will occur at the same location as the existing injection from the Tandem.

  3. Upgrade of the electron beam ion trap in Shanghai

    SciTech Connect (OSTI)

    Lu, D.; Yang, Y.; Xiao, J.; Shen, Y.; Fu, Y.; Wei, B.; Yao, K.; Hutton, R.; Zou, Y., E-mail: zouym@fudan.edu.cn [The Key Lab of Applied Ion Beam Physics, Ministry of Education, 200433 Shanghai (China); Shanghai EBIT Lab, Institute of Modern Physics, Fudan University, 200433 Shanghai (China)

    2014-09-15T23:59:59.000Z

    Over the last few years the Shanghai electron beam ion trap (EBIT) has been successfully redesigned and rebuilt. The original machine, developed under collaboration with the Shanghai Institute of Applied Physics, first produced an electron beam in 2005. It could be tuned with electron energies between 1 and 130 keV and beam current up to 160 mA. After several years of operation, it was found that several modifications for improvements were necessary to reach the goals of better electron optics, higher photon detection, and ion injection efficiencies, and more economical running costs. The upgraded Shanghai-EBIT is made almost entirely from Ti instead of stainless steel and achieves a vacuum of less than 10{sup ?10} Torr, which helps to minimize the loss of highly changed ions through charge exchange. Meanwhile, a more compact structure and efficient cryogenic system, and excellent optical alignment have been of satisfactory. The magnetic field in the central trap region can reach up till 4.8 T with a uniformity of 2.77 × 10{sup ?4}. So far the upgraded Shanghai-EBIT has been operated up to an electron energy of 151 keV and a beam current of up to 218 mA, although promotion to even higher energy is still in progress. Radiation from ions as highly charged as Xe{sup 53+,} {sup 54+} has been produced and the characterization of current density is estimated from the measured electron beam width.

  4. MHD Induced Neutral Beam Ion Loss from NSTX Plasmas

    SciTech Connect (OSTI)

    D.S. Darrow, E.D. Fredrickson, N.N. Gorelenkov, A.L. Roquemore, and K. Shinohara

    2007-12-13T23:59:59.000Z

    Bursts of ~60 kHz activity on Mirnov coils occur frequently in NSTX plasmas and these are accompanied by bursts of neutral beam ion loss over a range in pitch angles. These losses have been measured with a scintillator type loss probe imaged with a high speed (>10,000 frames/s) video camera, giving the evolution of the energy and pitch angle distributions of the lost neutral beam ions over the course of the events. The instability occurs below the TAE frequency in NSTX (~100 kHz) in high beta plasmas and may be a beta driven Alfvén acoustic (BAAE) mode.

  5. The Heavy Ion Fusion Science Virtual National Laboratory

    E-Print Network [OSTI]

    Gilson, Erik

    and collaborators. P. K. Roy et al., Nucl. Instr. and Meth. in Phys. Res. A 606 22, (2009). The four CAPS produce current through each of the four sources. P. K. Roy #12;The Heavy Ion Fusion Science Virtual National P. Gilson Princeton Plasma Physics Laboratory #12;The Heavy Ion Fusion Science Virtual National

  6. Matching an H{sup –} beam into a radio frequency quadrupole at Rutherford Appleton Laboratory

    SciTech Connect (OSTI)

    Gabor, C., E-mail: christoph.gabor@stfc.ac.uk; Faircloth, D. C.; Lawrie, S. R.; Letchford, A. P. [STFC, Rutherford Appleton Laboratory, Harwell, Didcot OX11 0QX (United Kingdom)] [STFC, Rutherford Appleton Laboratory, Harwell, Didcot OX11 0QX (United Kingdom); Back, J. J. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom)] [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom)

    2014-02-15T23:59:59.000Z

    A major component of work being carried out to upgrade the ISIS spallation neutron source at Rutherford Appleton Laboratory (RAL) is the Front End Test Stand (FETS). FETS is aimed at improving the luminosity of the linac, and consists of a Penning ion source, Low Energy Beam Transport (LEBT), Radio Frequency Quadrupole (RFQ), and Medium Energy Beam Transport (MEBT). It may serve as a first part of the accelerator chain providing a 60 mA, 3 MeV H{sup –} beam up to a 10% duty cycle. The current output of the source and the transmission of the LEBT are reasonable, but there are issues with the alignment to provide a centred beam matched into the acceptance of the RFQ. Improvements have been made to the post acceleration to address this problem. Measurements with a collimated beam have been performed to understand the behaviour of the solenoids and steerer magnets. Comparing these results with simulations proved that, besides possible mechanical imperfections of the ion source and post acceleration assembly, agreement can only be achieved if the magnetic fields are distorted.

  7. Heavy Ion Fusion Science Virtual National Laboratory

    E-Print Network [OSTI]

    progress with more modest near-term budgets. #12;Slide 5 Heavy Ion Fusion Science Virtual National requirement: modest growth of HIFS-VNL budget from present 7.7 M$/yr to ~16M$/yr, including suppo

  8. Risk Management Plan Electron Beam Ion Source Project

    E-Print Network [OSTI]

    Risk Management Plan for the Electron Beam Ion Source Project (EBIS) Project # 06-SC-002. There are three specific areas of risk that can be controlled and managed by the EBIS Project team and these are and operations. The BNL ISM clearly indicates that risk management is everybody's business and will be factored

  9. Spin Observables in Reactions with Radioactive Ion Beams

    SciTech Connect (OSTI)

    Galindo-Uribarri, Alfredo {nmn} [ORNL; Urrego Blanco, Juan Pablo [ORNL

    2007-01-01T23:59:59.000Z

    Polarization observables in nuclear reactions with exotic nuclei will provide important information concerning structural properties of nuclei and reaction mechanisms. We are currently engaged in exploring the use of polarization observables with radioactive ion beams and in the development of a polarized cryogenic target.

  10. 21st International Conference on Ion Beam Analysis

    SciTech Connect (OSTI)

    Thevuthasan, Suntharampillai; Shutthanandan, V.; Wang, Yongqiang; Vizkelethy, Gyorgy; Rout, Bibhudutta

    2014-08-01T23:59:59.000Z

    This special issue of Nuclear Instruments and Methods in Physics Research B contains the proceedings of the 21st International Conference on Ion Beam Analysis (IBA – 2013). This conference was held in Marriott Waterfront in Seattle, Washington, USA during June 23–28, 2013.

  11. Dense Metal Plasma in a Solenoid for Ion Beam Neutralization

    SciTech Connect (OSTI)

    Anders, Andre; Kauffeldt, Marina; Oks, Efim M.; Roy, Prabir K.

    2010-10-30T23:59:59.000Z

    Space-charge neutralization is required to compress and focus a pulsed, high-current ion beam on a target for warm dense matter physics or heavy ion fusion experiments. We described approaches to produce dense plasma in and near the final focusing solenoid through which the ion beam travels, thereby providing an opportunity for the beam to acquire the necessary space-charge compensating electrons. Among the options are plasma injection from pulsed vacuum arc sources located outside the solenoid, and using a high current (> 4 kA) pulsed vacuum arc plasma from a ring cathode near the edge of the solenoid. The plasma distribution is characterized by photographic means, by an array of movable Langmuir probes, by a small single probe, and by evaluating Stark broadening of the Balmer H beta spectral line. In the main approach described here, the plasma is produced at several cathode spots distributed azimuthally on the ring cathode. It is shown that the plasma is essentially hollow, as determined by the structure of the magnetic field, though the plasma density exceeds 1014 cm-3 in practically all zones of the solenoid volume if the ring electrode is placed a few centimeters off the center of the solenoid. The plasma is non-uniform and fluctuating, however, since its density exceeds the ion beam density it is believed that this approach could provide a practical solution to the space charge neutralization challenge.

  12. Ultrahigh vacuum focused ion beam micromill and articles therefrom

    DOE Patents [OSTI]

    Lamartine, B.C.; Stutz, R.A.

    1998-02-24T23:59:59.000Z

    An ultrahigh vacuum focused ion beam micromilling apparatus and process are disclosed. Additionally, a durable data storage medium using the micromilling process is disclosed, the durable data storage medium capable of storing, e.g., digital or alphanumeric characters as well as graphical shapes or characters. 6 figs.

  13. ION BEAM MACHINING OF NIOBIUM WEAKLY SUPERCONDUCTING MICROBRIDGES

    E-Print Network [OSTI]

    Boyer, Edmond

    179 ION BEAM MACHINING OF NIOBIUM WEAKLY SUPERCONDUCTING MICROBRIDGES R. ADDE, P. CROZAT, S réduite représentant la structure à usiner. Les propriétés de microponts Josephson en niobium sont ensuite to be machin- ed. We describe and discuss the superconducting properties of niobium Josephson microbridges

  14. Ultrahigh vacuum focused ion beam micromill and articles therefrom

    DOE Patents [OSTI]

    Lamartine, Bruce C. (Los Alamos, NM); Stutz, Roger A. (Los Alamos, NM)

    1998-01-01T23:59:59.000Z

    An ultrahigh vacuum focused ion beam micromilling apparatus and process are isclosed. Additionally, a durable data storage medium using the micromilling process is disclosed, the durable data storage medium capable of storing, e.g., digital or alphanumeric characters as well as graphical shapes or characters.

  15. Direct fabrication of nanopores in a metal foil using focused ion beam with in situ measurements of the penetrating ion beam current

    SciTech Connect (OSTI)

    Nagoshi, Kotaro; Honda, Junki; Sakaue, Hiroyuki; Takahagi, Takayuki; Suzuki, Hitoshi [Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8530 (Japan)

    2009-12-15T23:59:59.000Z

    A through hole with a diameter less than 100 nm was fabricated in an Ag foil using only a focused ion beam (FIB) system and in situ measurements of the penetrating ion beam. During the drilling of the foil by a FIB of Ga{sup +} ions, the transmitted part of the beam was measured with an electrode mounted on the back face of the foil. When the beam current penetrating through the nanopore reached a certain value, irradiation was stopped and the area of the created aperture was measured with a scanning electron microscope. The resulting area was correlated with the current of the penetrating ion beam. This suggests that we can fabricate a nanopore of the desired size by controlling the ion beam via penetrating ion beam measurements. The smallest aperture thus created was circular with diameter of 30 nm.

  16. The High Flux Beam Reactor at Brookhaven National Laboratory

    SciTech Connect (OSTI)

    Shapiro, S.M.

    1994-12-31T23:59:59.000Z

    Brookhaven National Laboratory`s High Flux Beam Reactor (HFBR) was built because of the need of the scientist to always want `more`. In the mid-50`s the Brookhaven Graphite reactor was churning away producing a number of new results when the current generation of scientists, led by Donald Hughes, realized the need for a high flux reactor and started down the political, scientific and engineering path that led to the BFBR. The effort was joined by a number of engineers and scientists among them, Chemick, Hastings, Kouts, and Hendrie, who came up with the novel design of the HFBR. The two innovative features that have been incorporated in nearly all other research reactors built since are: (i) an under moderated core arrangement which enables the thermal flux to peak outside the core region where beam tubes can be placed, and (ii) beam tubes that are tangential to the core which decrease the fast neutron background without affecting the thermal beam intensity. Construction began in the fall of 1961 and four years later, at a cost of $12 Million, criticality was achieved on Halloween Night, 1965. Thus began 30 years of scientific accomplishments.

  17. LEVIS ion source and beam characterization on PBFA-II

    SciTech Connect (OSTI)

    Renk, T.J.; Tisone, G.C.; Adams, R.G.; Bailey, J.E.; Filuk, A.B.; Johnson, D.J.; Pointon, T.D.

    1993-12-31T23:59:59.000Z

    We report on the continuing development of the LEVIS (Laser Evaporation Ion Source) lithium active ion source for the 15-cm radial focussing ion diode on PBFA-11. We found previously that DC-heating of the anode surface to 150{degrees}C maximum for 5 hours resulted in a pure lithium beam. This paper discusses the characterization of LEVIS source uniformity by Faraday cup arrays and multiple lines of sight for visible light spectroscopy. These diagnostics give some evidence of nonuniformity in both A-K gap electric fields and ion current density. Despite this, however, the measured focal spot size appears smaller than with a passive LiF source operated in the same magnetic field topology. Experiments using a curved anode for vertical beam focussing show reduced ion beam turn-on delay by 5 ns by altering the magnetic field topology as well as anode curvature. Another 3--5 ns reduction was achieved by switching from a passive LiF to the active LEVIS source.

  18. Progress in bright ion beams for industry, medicine and fusion at LBNL

    E-Print Network [OSTI]

    Kwan, Joe W.

    2002-01-01T23:59:59.000Z

    HI FAN 1160 LBNL-50492 Progress in Bright Ion BeamsMedicine and Fusion at LBNL Joe W. Kwan Lawrence BerkeleyAbstract Recent progresses at LBNL in developing ion beams

  19. Hydrogen removal from e-beam deposited alumina thin films by oxygen ion beam

    SciTech Connect (OSTI)

    Das, Arijeet, E-mail: arijeet@rrcat.gov.in; Mukharjee, C., E-mail: arijeet@rrcat.gov.in; Rajiv, K., E-mail: arijeet@rrcat.gov.in; Bose, Aniruddha, E-mail: arijeet@rrcat.gov.in; Singh, S. D., E-mail: arijeet@rrcat.gov.in; Rai, S. K.; Ganguli, Tapas; Joshi, S. C.; Deb, S. K. [Raja Ramanna Centre for Advanced Technology, Indore-452013 (India); Phase, D. M. [UGC-DAE Consortium for Scientific Research, Indore-452017 (India)

    2014-04-24T23:59:59.000Z

    Hydrogen interstitials and oxygen vacancies defects create energy levels in the band gap of alumina. This limits the application of alumina as a high-k dielectric. A low thermal budget method for removal of hydrogen from alumina is discussed. It is shown that bombardment of alumina films with low energy oxygen ion beam during electron beam evaporation deposition decreases the hydrogen concentration in the film significantly.

  20. Electrostatic dispersion lenses and ion beam dispersion methods

    DOE Patents [OSTI]

    Dahl, David A. (Idaho Falls, ID) [Idaho Falls, ID; Appelhans, Anthony D. (Idaho Falls, ID) [Idaho Falls, ID

    2010-12-28T23:59:59.000Z

    An EDL includes a case surface and at least one electrode surface. The EDL is configured to receive through the EDL a plurality of ion beams, to generate an electrostatic field between the one electrode surface and either the case surface or another electrode surface, and to increase the separation between the beams using the field. Other than an optional mid-plane intended to contain trajectories of the beams, the electrode surface or surfaces do not exhibit a plane of symmetry through which any beam received through the EDL must pass. In addition or in the alternative, the one electrode surface and either the case surface or the other electrode surface have geometries configured to shape the field to exhibit a less abrupt entrance and/or exit field transition in comparison to another electrostatic field shaped by two nested, one-quarter section, right cylindrical electrode surfaces with a constant gap width.

  1. Analytical and numerical studies of heavy ion beam transport in the fusion chamber

    E-Print Network [OSTI]

    Kaganovich, Igor

    Analytical and numerical studies of heavy ion beam transport in the fusion chamber IGOR D to acceptable levels. During ion beam propagation in the chamber, electrons are drawn into the beam, Princeton, New Jersey 08543, USA Abstract The propagation of a high-current finite-length ion charge bunch

  2. Microchip and wedge ion funnels and planar ion beam analyzers using same

    DOE Patents [OSTI]

    Shvartsburg, Alexandre A; Anderson, Gordon A; Smith, Richard D

    2012-10-30T23:59:59.000Z

    Electrodynamic ion funnels confine, guide, or focus ions in gases using the Dehmelt potential of oscillatory electric field. New funnel designs operating at or close to atmospheric gas pressure are described. Effective ion focusing at such pressures is enabled by fields of extreme amplitude and frequency, allowed in microscopic gaps that have much higher electrical breakdown thresholds in any gas than the macroscopic gaps of present funnels. The new microscopic-gap funnels are useful for interfacing atmospheric-pressure ionization sources to mass spectrometry (MS) and ion mobility separation (IMS) stages including differential IMS or FAIMS, as well as IMS and MS stages in various configurations. In particular, "wedge" funnels comprising two planar surfaces positioned at an angle and wedge funnel traps derived therefrom can compress ion beams in one dimension, producing narrow belt-shaped beams and laterally elongated cuboid packets. This beam profile reduces the ion density and thus space-charge effects, mitigating the adverse impact thereof on the resolving power, measurement accuracy, and dynamic range of MS and IMS analyzers, while a greater overlap with coplanar light or particle beams can benefit spectroscopic methods.

  3. Use of radial self-field geometry for intense pulsed ion beam generation above 6 MeV on Hermes III.

    SciTech Connect (OSTI)

    Renk, Timothy Jerome; Harper-Slaboszewicz, Victor Jozef; Ginn, William Craig; Mikkelson, Kenneth A.; Schall, Michael; Cooper, Gary Wayne

    2012-12-01T23:59:59.000Z

    We investigate the generation and propagation of intense pulsed ion beams at the 6 MeV level and above using the Hermes III facility at Sandia National Laboratories. While high-power ion beams have previously been produced using Hermes III, we have conducted systematic studies of several ion diode geometries for the purpose of maximizing focused ion energy for a number of applications. A self-field axial-gap diode of the pinch reflex type and operated in positive polarity yielded beam power below predicted levels. This is ascribed both to power flow losses of unknown origin upstream of the diode load in Hermes positive polarity operation, and to anomalies in beam focusing in this configuration. A change to a radial self-field geometry and negative polarity operation resulted in greatly increased beam voltage (> 6 MeV) and estimated ion current. A comprehensive diagnostic set was developed to characterize beam performance, including both time-dependent and time-integrated measurements of local and total beam power. A substantial high-energy ion population was identified propagating in reverse direction, i.e. from the back side of the anode in the electron beam dump. While significant progress was made in increasing beam power, further improvements in assessing the beam focusing envelope will be required before ultimate ion generation efficiency with this geometry can be completely determined.

  4. Applied Focused Ion Beam Techniques for Sample Preparation of Astromaterials for Integrated Nano-Analysis

    SciTech Connect (OSTI)

    Graham, G A; Teslich, N E; Kearsley, A T; Stadermann, F J; Stroud, R M; Dai, Z R; Ishii, H A; Hutcheon, I D; Bajt, S; Snead, C J; Weber, P K; Bradley, J P

    2007-02-20T23:59:59.000Z

    Sample preparation is always a critical step in study of micrometer sized astromaterials available for study in the laboratory, whether their subsequent analysis is by electron microscopy or secondary ion mass spectrometry. A focused beam of gallium ions has been used to prepare electron transparent sections from an interplanetary dust particle, as part of an integrated analysis protocol to maximize the mineralogical, elemental, isotopic and spectroscopic information extracted from one individual particle. In addition, focused ion beam techniques have been employed to extract cometary residue preserved on the rims and walls of micro-craters in 1100 series aluminum foils that were wrapped around the sample tray assembly on the Stardust cometary sample collector. Non-ideal surface geometries and inconveniently located regions of interest required creative solutions. These include support pillar construction and relocation of a significant portion of sample to access a region of interest. Serial sectioning, in a manner similar to ultramicrotomy, is a significant development and further demonstrates the unique capabilities of focused ion beam microscopy for sample preparation of astromaterials.

  5. EBIT (Electron Beam Ion Trap), N-Division Experimental Physics. Annual report, 1994

    SciTech Connect (OSTI)

    Schneider, D. [ed.

    1995-10-01T23:59:59.000Z

    The experimental groups in the Electron Beam Ion Trap (EBIT) program continue to perform front-line research with trapped and extracted highly charged ions (HCI) in the areas of ion/surface interactions, atomic spectroscopy, electron-ion interaction and structure measurements, highly charged ion confinement, and EBIT development studies. The ion surface/interaction studies which were initiated five years ago have reached a stage where they an carry out routine investigations, as well as produce breakthrough results towards the development of novel nanotechnology. At EBIT and SuperEBIT studies of the x-ray emission from trapped ions continue to produce significant atomic structure data with high precision for few electron systems of high-Z ions. Furthermore, diagnostics development for magnetic and laser fusion, supporting research for the x-ray laser and weapons programs, and laboratory astrophysics experiments in support of NASA`s astrophysics program are a continuing effort. The two-electron contributions to the binding energy of helium like ions were measured for the first time. The results are significant because their precision is an order of magnitude better than those of competing measurements at accelerators, and the novel technique isolates the energy corrections that are the most interesting. The RETRAP project which was initiated three years ago has reached a stage where trapping, confining and electronic cooling of HCI ions up to Th{sup 80+} can be performed routinely. Measurements of the rates and cross sections for electron transfer from H{sub 2} performed to determine the lifetime of HCI up to Xe{sup q+} and Th{sup q+} (35 {le} q {le} 80) have been studied at mean energies estimated to be {approximately} 5 q eV. This combination of heavy ions with very high charges and very low energies is rare in nature, but may be encountered in planned fusion energy demonstration devices, in highly charged ion sources, or in certain astrophysical events.

  6. Method for measuring and controlling beam current in ion beam processing

    DOE Patents [OSTI]

    Kearney, Patrick A. (Livermore, CA); Burkhart, Scott C. (Livermore, CA)

    2003-04-29T23:59:59.000Z

    A method for producing film thickness control of ion beam sputter deposition films. Great improvements in film thickness control is accomplished by keeping the total current supplied to both the beam and suppressor grids of a radio frequency (RF) in beam source constant, rather than just the current supplied to the beam grid. By controlling both currents, using this method, deposition rates are more stable, and this allows the deposition of layers with extremely well controlled thicknesses to about 0.1%. The method is carried out by calculating deposition rates based on the total of the suppressor and beam currents and maintaining the total current constant by adjusting RF power which gives more consistent values.

  7. Experiments with planar inductive ion source meant for creation of H+ Beams

    E-Print Network [OSTI]

    Vainionpaa, J.H.; Kalvas, T.; Hahto, S.K.; Reijonen, J.

    2008-01-01T23:59:59.000Z

    three type B ion sources with different chamber diameter Dthe ion source A was made so that cylindrical chamber wallcylindrical chamber wall. Extraction of the ion beam and gas

  8. Production and acceleration of ion beams by laser ablation

    SciTech Connect (OSTI)

    Velardi, L.; Siciliano, M. V.; Delle Side, D.; Nassisi, V. [Department of Physics and I.N.F.N., LEAS Laboratory, University of Salento, Via Provinciale Lecce-Monteroni, 73100 Lecce (Italy)

    2012-02-15T23:59:59.000Z

    In this work, we present a new pulsed laser ablation technique to obtain energetic ion beams. The accelerator we made is a compact device able to extract and accelerate the ionic components of plasma up to 160 keV per charge state. It is composed by a generating chamber containing an expansion chamber used like first electrode. Next, a second electrode connected to ground and a third electrode connected to negative voltage are used. The third electrode is used also as Faraday cup. By the analysis of the ion signals we studied the plume parameters such as TOF accelerated signals, charge state, and divergence.

  9. Formation of nanosize structures on a silicon substrate by method of focused ion beams

    SciTech Connect (OSTI)

    Ageev, O. A.; Kolomiytsev, A. S.; Konoplev, B. G., E-mail: kbg@tsure.ru [Technological Institute of the Southern Federal University (Russian Federation)

    2011-12-15T23:59:59.000Z

    The results of experimental studies of modes in which nanosize structures are formed on a silicon substrate by method of focused ion beams are presented. Dependences of the diameter and depth of the nanosize structures on the ion beam current and time of exposure to the ion beam at a point are obtained. It is demonstrated that the main factor determining the rate of ion-beam milling is the ion beam current. The results of the study can be used in the development of technological processes for the fabrication of components for nanoelectronics and nanosystems engineering.

  10. Nanostructured ion beam-modified Ge films for high capacity Li ion battery anodes

    SciTech Connect (OSTI)

    Rudawski, N. G.; Darby, B. L.; Yates, B. R.; Jones, K. S. [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611-6400 (United States); Elliman, R. G. [Department of Electronic Materials Engineering, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia); Volinsky, A. A. [Department of Mechanical Engineering, University of South Florida, Tampa Florida 33620 (United States)

    2012-02-20T23:59:59.000Z

    Nanostructured ion beam-modified Ge electrodes fabricated directly on Ni current collector substrates were found to exhibit excellent specific capacities during electrochemical cycling in half-cell configuration with Li metal for a wide range of cycling rates. Structural characterization revealed that the nanostructured electrodes lose porosity during cycling but maintain excellent electrical contact with the metallic current collector substrate. These results suggest that nanostructured Ge electrodes have great promise for use as high performance Li ion battery anodes.

  11. Photon trap for neutralization of negative ions beams

    E-Print Network [OSTI]

    Popov, S S; Ivanov, A A; Kotelnikov, I A

    2015-01-01T23:59:59.000Z

    For effectively neutralization of the powerful negative ions beams of hydrogen and deuterium the photon target is considered in long time. The attractiveness of the traditional approach (Fabry-Perot resonators) to their creation is limited to a number of stringent technical requirements and large economic costs. In this paper we propose a new concept of non-resonant photon trap (storage) for creation more technologically simple optical neutralizers.

  12. Direct-write milling of diamond by a focused oxygen ion beam

    E-Print Network [OSTI]

    Martin, Aiden A; Botman, Aurelien; Toth, Milos; Aharonovich, Igor

    2015-01-01T23:59:59.000Z

    Recent advances in focused ion beam technology have enabled high-resolution, direct-write nanofabrication using light ions. Studies with light ions to date have, however, focused on milling of materials where sub-surface ion beam damage does not inhibit device performance. Here we report on direct-write milling of single crystal diamond using a focused beam of oxygen ions. Material quality is assessed by Raman and luminescence analysis, and reveals that the damage layer generated by oxygen ions can be removed by nonintrusive post-processing methods such as localised electron beam induced chemical etching.

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

    E-Print Network [OSTI]

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

    2013-01-01T23:59:59.000Z

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

  14. Control system for the Holifield Radioactive Ion Beam Facility

    SciTech Connect (OSTI)

    Tatum, B.A.; Juras, R.C.; Meigs, M.J.

    1995-12-31T23:59:59.000Z

    A new accelerator control system is being implemented as part of the development of the Holifield Radioactive Ion Beam Facility (HRIBF), a first generation radioactive ion beam (RIB) facility. The pre- existing accelerator control systems are based on 1970`s technology and addition or alteration of controls is cumbersome and costly. A new, unified control system for the cyclotron and tandem accelerators, the RIB injector, ion sources, and accelerator beam lines is based on a commercial product from Vista Control Systems, Inc. Several other accelerator facilities, as well as numerous industrial sites, are now using this system. The control system is distributed over a number of computers which communicate over Ethernet and is easily extensible. Presently, implementation at the HRIBF is based on VAX/VMS, VAX/ELN, VME, and Allen-Bradley PLC5 programmable logic controller architectures. Expansion to include UNIX platforms and CAMAC hardware support is planned. Operator interface is via X- terminals. The system has proven to be quite powerful, yet is has been easy to implement with a small staff. A Vista users group has resulted in shared software to implement specific controls. This paper details present system features and future implementations at the HRIBF.

  15. PARALLEL ION BEAM PROFILE SCAN USING LASER WIRE

    SciTech Connect (OSTI)

    Liu, Yun [ORNL; Aleksandrov, Alexander V [ORNL; Huang, Chunning [ORNL; Long, Cary D [ORNL; Dickson, Richard W [ORNL

    2013-01-01T23:59:59.000Z

    We report on the world s first experiment of a parallel profile scan of the hydrogen ion (H-) beam using a laser wire system. The system was developed at the superconducting linac of the Spallation Neutron Source (SNS) accelerator complex. The laser wire profile scanner is based on a photo-detachment process and therefore can be conducted on an operational H- beam in a nonintrusive manner. The parallel profile scanning system makes it possible to simultaneously measure profiles of the 1-MW neutron production H- beam at 9 different locations of the linac by using a single light source. This paper describes the design, optical system and software platform development, and measurement results of the parallel profile scanning system.

  16. External micro ion-beam analysis (X-MIBA)

    SciTech Connect (OSTI)

    Doyle, B.L.; Lee, S.R. (Sandia National Labs., Albuquerque, NM (USA)); Walsh, D.S. (Idaho State Univ., Pocatello, ID (USA))

    1989-01-01T23:59:59.000Z

    In-air or external ion beam analysis combined with 10--100 {mu}m spatial resolution, is a truly unique feature of the nuclear microprobe technique. PIXE has been performed externally for many years, but recently, other IBA techniques such as backscattering and nuclear reaction depth profiling measurements have been made in air. Presently, the use of eXternal Micro Ion-Beam Analysis, or X-MIBA, is being attempted at a growing number of microprobe facilities; however, the full potential of this new technique remains relatively unexploited. This paper will review the X-MIBA technique with emphasis on optimization of exit foil geometries, beam focusing and spot size considerations, external IBA techniques, and radiation hazards associated with the direct and scattered beam, nuclear reaction products and radionuclei production in the air. The unique in-air analysis advantages of no pump down, and essentially unrestricted sample size or state (solid, liquid etc.), has resulted in a myriad of applications of this technique at Sandia, which are featured as examples. 52 refs., 8 figs., 2 tabs.

  17. Reduction of Glass Surface Reflectance by Ion Beam Surface Modification

    SciTech Connect (OSTI)

    Mark Spitzer

    2011-03-11T23:59:59.000Z

    This is the final report for DOE contract DE-EE0000590. The purpose of this work was to determine the feasibility of the reduction of the reflection from the front of solar photovoltaic modules. Reflection accounts for a power loss of approximately 4%. A solar module having an area of one square meter with an energy conversion efficiency of 18% generates approximately 180 watts. If reflection loss can be eliminated, the power output can be increased to 187 watts. Since conventional thin-film anti-reflection coatings do not have sufficient environmental stability, we investigated the feasibility of ion beam modification of the glass surface to obtain reduction of reflectance. Our findings are generally applicable to all solar modules that use glass encapsulation, as well as commercial float glass used in windows and other applications. Ion implantation of argon, fluorine, and xenon into commercial low-iron soda lime float glass, standard float glass, and borosilicate glass was studied by implantation, annealing, and measurement of reflectance. The three ions all affected reflectance. The most significant change was obtained by argon implantation into both low-iron and standard soda-lime glass. In this way samples were formed with reflectance lower than can be obtained with a single-layer coatings of magnesium fluoride. Integrated reflectance was reduced from 4% to 1% in low-iron soda lime glass typical of the glass used in solar modules. The reduction of reflectance of borosilicate glass was not as large; however borosilicate glass is not typically used in flat plate solar modules. Unlike conventional semiconductor ion implantation doping, glass reflectance reduction was found to be tolerant to large variations in implant dose, meaning that the process does not require high dopant uniformity. Additionally, glass implantation does not require mass analysis. Simple, high current ion implantation equipment can be developed for this process; however, before the process can be employed on full scale solar modules, equipment must be developed for ion implanting large sheets of glass. A cost analysis shows that the process can be economical. Our finding is that the reduction of reflectance by ion beam surface modification is technically and economically feasible. The public will benefit directly from this work by the improvement of photovoltaic module efficiency, and indirectly by the greater understanding of the modification of glass surfaces by ion beams.

  18. Rare-earth neutral metal injection into an electron beam ion trap plasma

    SciTech Connect (OSTI)

    Magee, E. W., E-mail: magee1@llnl.gov; Beiersdorfer, P.; Brown, G. V. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Hell, N. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Dr. Remeis-Sternwarte and ECAP, Universität Erlangen-Nürnberg, 96049 Bamberg (Germany)

    2014-11-15T23:59:59.000Z

    We have designed and implemented a neutral metal vapor injector on the SuperEBIT high-energy electron beam ion trap at the Lawrence Livermore National Laboratory. A horizontally directed vapor of a europium metal is created using a thermal evaporation technique. The metal vapor is then spatially collimated prior to injection into the trap. The source's form and quantity constraints are significantly reduced making plasmas out of metal with vapor pressures ?10{sup ?7} Torr at ?1000?°C more obtainable. A long pulsed or constant feed metal vapor injection method adds new flexibility by varying the timing of injection and rate of material being introduced into the trap.

  19. Mechanical and tribological properties of ion beam-processed surfaces

    SciTech Connect (OSTI)

    Kodali, P.

    1998-01-01T23:59:59.000Z

    The intent of this work was to broaden the applications of well-established surface modification techniques and to elucidate the various wear mechanisms that occur in sliding contact of ion-beam processed surfaces. The investigation included characterization and evaluation of coatings and modified surfaces synthesized by three surface engineering methods; namely, beam-line ion implantation, plasma-source ion implantation, and DC magnetron sputtering. Correlation among measured properties such as surface hardness, fracture toughness, and wear behavior was also examined. This dissertation focused on the following areas of research: (1) investigating the mechanical and tribological properties of mixed implantation of carbon and nitrogen into single crystal silicon by beam-line implantation; (2) characterizing the mechanical and tribological properties of diamond-like carbon (DLC) coatings processed by plasma source ion implantation; and (3) developing and evaluating metastable boron-carbon-nitrogen (BCN) compound coatings for mechanical and tribological properties. The surface hardness of a mixed carbon-nitrogen implant sample improved significantly compared to the unimplanted sample. However, the enhancement in the wear factor of this sample was found to be less significant than carbon-implanted samples. The presence of nitrogen might be responsible for the degraded wear behavior since nitrogen-implantation alone resulted in no improvement in the wear factor. DLC coatings have low friction, low wear factor, and high hardness. The fracture toughness of DLC coatings has been estimated for the first time. The wear mechanism in DLC coatings investigated with a ruby slider under a contact stress of 1 GPa was determined to be plastic deformation. The preliminary data on metastable BCN compound coatings indicated high friction, low wear factor, and high hardness.

  20. Application of the Ta liner technique to produce Ca beams at INFN-Legnaro National Laboratories (INFN-LNL)

    SciTech Connect (OSTI)

    Galatà, A., E-mail: alessio.galata@lnl.infn.it; Sattin, M.; Manzolaro, M.; Martini, D.; Facco, A. [INFN-Legnaro National Laboratories, Legnaro (Pd) (Italy)] [INFN-Legnaro National Laboratories, Legnaro (Pd) (Italy); Tinschert, K.; Spaedtke, P.; Lang, R. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt (Germany)] [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt (Germany); Kulevoy, T. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation)] [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation)

    2014-02-15T23:59:59.000Z

    The ECR ion sources are able to produce a wide variety of highly charged metallic ion beams thanks to the development of different techniques (ovens, sputtering, direct insertion, metal ions from volatile compounds (MIVOC)). In the case of the ovens, the sticking of the hot vapors on the surface of the plasma chamber leads to high material consumption rates. For elements like Ca, a tantalum liner inserted inside the chamber can be used to limit this phenomenon. The modeling of temperature distribution inside the chamber with and without the liner was carried out with COMSOL-multiphysics code. Results of simulation and the comparison with experiments performed at INFN-Legnaro National Laboratories with Ca beams are discussed.

  1. Ion beam heated target simulations for warm dense matter physics and inertial fusion energy$

    E-Print Network [OSTI]

    Wurtele, Jonathan

    Ion beam heated target simulations for warm dense matter physics and inertial fusion energy$ J Keywords: Ion beam heating Warm dense matter Inertial fusion energy targets Hydrodynamic simulation a b fusion energy-related beam-target coupling. Simulations of various target materials (including solids

  2. Ion acceleration from thin foil and extended plasma targets by slow electromagnetic wave and related ion-ion beam instability

    SciTech Connect (OSTI)

    Bulanov, S. V. [QuBS, Japan Atomic Energy Agency, Kizugawa, Kyoto, 619-0215 (Japan); A. M. Prokhorov Institute of General Physics RAS, Moscow, 119991 (Russian Federation); Esirkepov, T. Zh.; Kando, M. [QuBS, Japan Atomic Energy Agency, Kizugawa, Kyoto, 619-0215 (Japan); Pegoraro, F. [Physical Department, University of Pisa, Pisa 56127 (Italy); Bulanov, S. S. [University of California, Berkeley, California 94720 (United States); Geddes, C. G. R.; Schroeder, C. B.; Esarey, E. [Lawrence Berkeley National Laboratory, Berkeley, California, 94720 (United States); Leemans, W. P. [University of California, Berkeley, California 94720 (United States); Lawrence Berkeley National Laboratory, Berkeley, California, 94720 (United States)

    2012-10-15T23:59:59.000Z

    When ions are accelerated by the radiation pressure of a laser pulse, their velocity cannot exceed the pulse group velocity which can be considerably smaller than the speed of light in vacuum. This is demonstrated in two cases corresponding to a thin foil target irradiated by high intensity laser light and to the hole boring produced in an extended plasma by the laser pulse. It is found that the beams of accelerated ions are unstable against Buneman-like and Weibel-like instabilities which results in the broadening of the ion energy spectrum.

  3. Radioactive Ions Production Ring for Beta-Beams

    E-Print Network [OSTI]

    Benedetto, E; Wehner, J

    2010-01-01T23:59:59.000Z

    Within the FP7 EUROnu program, Work Package 4 addresses the issues of production and acceleration of 8Li and 8B isotopes through the Beta-Beam complex, for the production of electron-neutrino. One of the major critical issues is the production of a high enougth ion ßux, to fulÞll the requirements for physics. In alternative to the direct ISOL production method, a new ap- proach is proposed in [1]. The idea is to use a compact ring for Litium ions at 25 MeV and an internal He or D target, in which the radioactive-isotopes production takes place. The beam is expected to survive for several thousands of turns, therefore cooling in 6D is required and, according this scheme, the ionization cooling provided by the target itself and a suitable RF system would be sufÞcient. We present some preliminary work on the Production ring lat- tice design and cooling issues, for the 7Li ions, and propose plans for future studies, within the EUROnu program.

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

    DOE Patents [OSTI]

    Hershcovitch, A.

    1984-02-13T23:59:59.000Z

    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. Method and means of directing an ion beam onto an insulating surface for ion implantation or sputtering

    DOE Patents [OSTI]

    Gruen, Dieter M. (Downers Grove, IL); Krauss, Alan R. (Naperville, IL); Siskind, Barry (Downers Grove, IL)

    1981-01-01T23:59:59.000Z

    A beam of ions is directed under control onto an insulating surface by supplying simultaneously a stream of electrons directed at the same surface in a quantity sufficient to neutralize the overall electric charge of the ion beam and result in a net zero current flow to the insulating surface. The ion beam is adapted particularly both to the implantation of ions in a uniform areal disposition over the insulating surface and to the sputtering of atoms or molecules of the insulator onto a substrate.

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

    DOE Patents [OSTI]

    Hershcovitch, Ady (Mount Sinai, NY)

    1987-01-01T23:59:59.000Z

    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 intersected by a beam of laser light. Photodetachment is effected in a uniform magnetic field that is provided around the beam of H.sup.- ions to spin polarize the H.sup.- ions and produce first and second populations or groups of ions, having their respective proton spin aligned either with the magnetic field or opposite to it. The intersecting beam of laser light is directed to selectively neutralize a majority of the ions in only one population, or given spin polarized group of H.sup.- ions, without neutralizing the ions in the other group thereby forming a population of H.sup.- ions each of which has its proton spin down, and a second group or population of H.sup.o atoms having proton spin up. Finally, the two groups of ions are separated from each other by magnetically bending the group of H.sup.- ions away from the group of neutralized ions, thereby to form an intense H.sup.- ion beam that is directed toward a predetermined objective.

  7. One-dimensional ordering of ultra-low density ion beams in a storage ring

    E-Print Network [OSTI]

    Okamoto, H.; Okabe, K.; Yuri, Y.; Mohl, D.; Sessler, A.M.

    2004-01-01T23:59:59.000Z

    One-dimensional ordering of ultra-low density ion beams in ais applicable to an ultra-low density beam where collectiveabout 10 cm. In such an ultra-low density regime, no collec-

  8. Determination of ion track radii in amorphous matrices via formation of nano-clusters by ion-beam irradiation

    SciTech Connect (OSTI)

    Buljan, M.; Karlusic, M.; Bogdanovic-Radovic, I.; Jaksic, M.; Radic, N. [Rudjer Boskovic Institute, Bijenicka cesta 54, 10000 Zagreb (Croatia); Salamon, K. [Institute of Physics, 10000 Zagreb (Croatia); Bernstorff, S. [Sincrotrone Trieste, 34102 Basovizza (Italy)

    2012-09-03T23:59:59.000Z

    We report on a method for the determination of ion track radii, formed in amorphous materials by ion-beam irradiation. The method is based on the addition to an amorphous matrix of a small amount of foreign atoms, which easily diffuse and form clusters when the temperature is sufficiently increased. The irradiation causes clustering of these atoms, and the final separations of the formed clusters are dependent on the parameters of the ion-beam. Comparison of the separations between the clusters that are formed by ions with different properties in the same type of material enables the determination of ion-track radii.

  9. FINAL FOCUS ION BEAM INTENSITY FROM TUNGSTEN FOIL CALORIMETER AND SCINTILLATOR IN NDCX-I

    E-Print Network [OSTI]

    Lidia, S.M.

    2010-01-01T23:59:59.000Z

    FOCUS ION BEAM INTENSITY FROM TUNGSTEN FOIL CALORIMETER ANDtemperature rise in the tungsten foil. A cross-calibrationis obtained with a 3µm thick tungsten foil calorimeter and

  10. Study of ion beam generation from interaction of 10 µm with...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (but acceleration time is longer). Scaling of ion acceleration with CO 2 lasers Gas jet as an ion beam source * Pure (compared to solid targets which become quickly covered in...

  11. Experimental test of a microwave ion beam source in oxygen

    SciTech Connect (OSTI)

    Asmussen, J.; Dahimene, M.

    1987-01-01T23:59:59.000Z

    Recent experiments have demonstrated a microwave (2.45 GHz) plasma disk ion source operating with inert gases both with and without an applied static magnetic field. Earlier results were reported using a preliminary, multicusp static magnetic field configuration produced by alternating pole, small, --2.5 kG rare earth magnets surrounding the microwave discharge zone. This electrodeless ion source has been rebuilt incorporating several improvements and has been experimentally tested with different discharge diffusion lengths. The improvements include removing the rare earth magnets from the inside of the microwave cavity and embedding them in the cavity walls. The placement and strength of the magnets allows electron cyclotron resonant surfaces (--875 G) to lie entirely within the discharge zone. Discharges with different diffusion lengths were created by varying the thickness of the disk-shaped discharge zone. The experimental performance with and without a static magnetic field is discussed at the low flow rates of 2--10 sccm and using a 2.5 cm diam double grid set. Experimental test results are compared to similar ion beam sources in oxygen that employ a dc discharge. The expected lifetime, startup, and shutdown problems and maintenance are also reviewed.

  12. Proceedings of the workshop on the production and use of intense radioactive beams at the Isospin Laboratory

    SciTech Connect (OSTI)

    Garrett, J.D. [ed.

    1992-12-31T23:59:59.000Z

    These proceedings report the deliberations of a 3 1/2 day workshop on the Production and Use of Intense Radioactive Ion Beams at the Isospin Laboratory, which was held at the Joint Institute for Heavy Ion Research in Oak Ridge, Tennessee, October 1992. The purpose of this workshop was not to duplicate the programs of other recent radioactive ion beam workshops or international conferences that have focused on the scientific concepts which radioactive beams can, and in fact already are, addressing. Instead, the intent was to address the technical problems associated with the construction of the next generation ISOL facility and to initiate a discussion of the type of experimental equipment that should be developed for such a facility. We have tried to bring together in Oak Ridge the world`s experts in radioactive targets/ion sources, light and heavy-ion accelerators, and detection systems. After 1 1/2 days of overview presentations, the participants divided into three discussion groups (Experiments with Radioactive Beams, Target Ion Sources and Mass Separation, and Accelerators-Primary and Secondary) for 1 1/2 days of detailed discussions of the most pertinent issues. The final session was devoted to reports from each of the discussion groups and a general discussion of where to go from here. An outgrowth of these discussions was the establishment of working groups to coordinate future technical developments associated with the pertinent issues. The proceedings include the text of all the overview presentations, reports from each discussion group, as well as contributions from those participants who chose to provide the text of their presentations in the discussion groups and the Concluding Remarks. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  13. Studies of Limits on Uncontrolled Heavy Ion Beam Losses for Allowing Hands-On Maintenance

    SciTech Connect (OSTI)

    Reginald M. Ronningen; Igor Remec

    2010-09-11T23:59:59.000Z

    Dose rates from accelerator components activated by 1 W/m beam losses are obtained semiempirically for a 1 GeV proton beam and by use of Monte Carlo transport codes for the proton beam and for 777 MeV/u 3He, 500 MeV/u 48Ca, 86Kr, 136Xe, and 400 MeV/u 238U ions. The dose rate obtained by the semi-empirical method, 0.99 mSv/h (99 mrem/h) at 30 cm, 4 h after 100 d irradiation by a 1-GeV proton beam, is consistent with studies at several accelerator facilities and with adopted hands-on maintenance dose rate limits. Monte Carlo simulations verify this result for protons and extend studies to heavy ion beam losses in drift-tube linac and superconducting linac accelerating structures. The studies indicate that the 1 W/m limit imposed on uncontrolled beam losses for high-energy proton beams might be relaxed for heavy ion beams. These studies further suggest that using the ratio of neutrons produced by a heavy ion beam to neutrons produced by a proton beam along with the dose rate from the proton beam (for thin-target scenarios) should allow an estimate of the dose rates expected from heavy ion beam losses.

  14. Modulator considerations for beam chopping in the low energy beam transport at the SSC Laboratory

    SciTech Connect (OSTI)

    Anderson, D.; Pappas, G.

    1991-06-01T23:59:59.000Z

    Beam chopping in the low energy transport line at the Superconducting Super Collider Laboratory is accomplished using an electrostatic deflection system. LINAC requirements dictate the design of two modulators operating at 10 Hz with rise and fall times (as measured from approximately 10--99%) of {approximately}100 ns. Design of the first pulser, normally at 10 kV and pulsed to ground potential, utilizes a transformer-coupled diode-clamped solid state circuit to achieve the 2--35 {mu}s pulse width range required. The second pulser, which pulses from ground to approximately 7 kV, relies on a series vacuum tube circuit. The current designs, as well as recent test results and other circuit topologies considered, will be presented. 6 refs.

  15. Ion beam sputter target and method of manufacture

    DOE Patents [OSTI]

    Higdon, Clifton; Elmoursi, Alaa A.; Goldsmith, Jason; Cook, Bruce; Blau, Peter; Jun, Qu; Milner, Robert

    2014-09-02T23:59:59.000Z

    A target for use in an ion beam sputtering apparatus made of at least two target tiles where at least two of the target tiles are made of different chemical compositions and are mounted on a main tile and geometrically arranged on the main tile to yield a desired chemical composition on a sputtered substrate. In an alternate embodiment, the tiles are of varied thickness according to the desired chemical properties of the sputtered film. In yet another alternate embodiment, the target is comprised of plugs pressed in a green state which are disposed in cavities formed in a main tile also formed in a green state and the assembly can then be compacted and then sintered.

  16. Nanostructuring superconductors by ion beams: A path towards materials engineering

    SciTech Connect (OSTI)

    Gerbaldo, Roberto; Ghigo, Gianluca; Gozzelino, Laura; Laviano, Francesco [Department of Applied Science and Technology, Politecnico di Torino c.so Duca degli Abruzzi 24, 10129 Torino, Italy and INFN Sez. Torino, via P. Giuria 1, 10125 Torino (Italy); Amato, Antonino; Rovelli, Alberto [INFN Laboratori Nazionali del Sud, via S. Sofia 62, 95125 Catania (Italy); Cherubini, Roberto [INFN Laboratori Nazionali di Legnaro, viale dell'Universita 2, 35020 Legnaro (Italy)

    2013-07-18T23:59:59.000Z

    The paper deals with nanostructuring of superconducting materials by means of swift heavy ion beams. The aim is to modify their structural, optical and electromagnetic properties in a controlled way, to provide possibility of making them functional for specific applications. Results are presented concerning flux pinning effects (implantation of columnar defects with nanosize cross section to enhance critical currents and irreversibility fields), confined flux-flow and vortex guidance, design of devices by locally tailoring the superconducting material properties, analysis of disorder-induced effects in multi-band superconductors. These studies were carried out on different kinds of superconducting samples, from single crystals to thin films, from superconducting oxides to magnesium diboride, to recently discovered iron-based superconductors.

  17. Nuclear reactions with 11C and 14O radioactive ion beams

    SciTech Connect (OSTI)

    Guo, Fanqing

    2004-12-09T23:59:59.000Z

    Radioactive ion beams (RIBs) have been shown to be a useful tool for studying proton-rich nuclides near and beyond the proton dripline and for evaluating nuclear models. To take full advantage of RIBs, Elastic Resonance Scattering in Inverse Kinematics with Thick Targets (ERSIKTT), has proven to be a reliable experimental tool for investigations of proton unbound nuclei. Following several years of effort, Berkeley Experiments with Accelerated Radioactive Species (BEARS), a RIBs capability, has been developed at the Lawrence Berkeley National Laboratory's 88-Inch Cyclotron. The current BEARS provides two RIBs: a 11C beam of up to 2x108 pps intensity on target and an 14O beam of up to 3x104 pps intensity. While the development of the 11C beam has been relatively easy, a number of challenges had to be overcome to obtain the 14O beam. The excellent 11C beam has been used to investigate several reactions. The first was the 197Au(11C,xn)208-xnAt reaction, which was used to measure excitation functions for the 4n to 8n exit channels. The measured cross sections were generally predicted quite well using the fusion-evaporation code HIVAP. Possible errors in the branching ratios of ?? decays from At isotopes as well as the presence of incomplete fusion reactions probably contribute to specific overpredictions. 15F has been investigated by the p(14O,p)14O reaction with the ERSIKTT technology. Several 14O+p runs have been performed. Excellent energy calibration was obtained using resonances from the p(14N,p)14N reaction in inverse kinematics, and comparing the results to those obtained earlier with normal kinematics. The differences between 14N+p and 14O+p in the stopping power function have been evaluated for better energy calibration. After careful calibration, the energy levels of 15F were fitted with an R-matrix calculation. Spins and parities were assigned to the two observed resonances. This new measurement of the 15F ground state supports the disappearance of the Z = 8 proton magic number for odd Z, Tz=-3/2 nuclei. It is expected that future work on proton-rich nuclides will rely heavily on RIBs and/or mass separators. Currently, radioactive ion beam intensities are sufficient for the study of a reasonable number of very proton-rich nuclides.

  18. Ion beam characteristics of the controlatron/zetatron family of the gas filled neutron tubes

    SciTech Connect (OSTI)

    Berg, R.S.; Shope, L.A.; O'Neal, M.L.; Boers, J.E.; Bickes, R.W. Jr.

    1981-03-01T23:59:59.000Z

    A gas filled tube used to produce a neutron flux with the D(T,He/sup 4/)n reaction is described. Deuterium and tritium ions generated in a reflex discharge are extracted and accelerated to 100 keV by means of an accelerator electrode onto a deutero-tritide target electrode. The electrodes are designed to focus the ion beam onto the target. Total tube currents consisting of extracted ions, unsuppressed secondary electrons, and ions generated by interactions with the background gas are typically 100 mA. The characteristics of the extracted ion beam are discussed. Accelerating voltages greater than 50 kV are required to focus the beam through the accelerator aperture for configurations that give beams with the proper energy density onto the target. The perveance of the beam is discussed. Maximum perveance values are 2 to 20 nanopervs. Tube focusing and neutron production characteristics are described.

  19. Excited-Level Lifetimes and Hyperfine-Structure Measurements on Ions using Collinear Laser Ion-Beam Spectroscopy

    E-Print Network [OSTI]

    Jin, J.; Church, David A.

    1994-01-01T23:59:59.000Z

    resolve isotopic beams of Ca+ or Cl+. However, each isotopic mass had a different velocity, and hence Doppler shift, following subsequent acceleration to and within the DSS. Consequently ion isotopes other than the dominant iso- tope had significantly...

  20. Proceedings of the workshop on the science of intense radioactive ion beams

    SciTech Connect (OSTI)

    McClelland, J.B.; Vieira, D.J. (comps.)

    1990-10-01T23:59:59.000Z

    This report contains the proceedings of a 2-1/2 day workshop on the Science of Intense Radioactive Ion Beams which was held at the Los Alamos National Laboratory on April 10--12, 1990. The workshop was attended by 105 people, representing 30 institutions from 10 countries. The thrust of the workshop was to develop the scientific opportunities which become possible with a new generation intense Radioactive Ion Beam (RIB) facility, currently being discussed within North America. The workshop was organized around five primary topics: (1) reaction physics; (2) nuclei far from stability/nuclear structure; (3) nuclear astrophysics; (4) atomic physics, material science, and applied research; and (5) facilities. Overview talks were presented on each of these topics, followed by 1-1/2 days of intense parallel working group sessions. The final half day of the workshop was devoted to the presentation and discussion of the working group summary reports, closing remarks and a discussion of future plans for this effort.

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

    SciTech Connect (OSTI)

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

    2014-02-15T23:59:59.000Z

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

  2. Performance predictions for a laser intensified thermal beam for use in high resolution Focused Ion Beam instruments

    E-Print Network [OSTI]

    Wouters, S H W; Notermans, R P M J W; Debernardi, N; Mutsaers, P H A; Luiten, O J; Vredenbregt, E J D

    2014-01-01T23:59:59.000Z

    Photo-ionization of a laser-cooled and compressed atomic beam from a high-flux thermal source can be used to create a high-brightness ion beam for use in Focus Ion Beam (FIB) instruments. Here we show using calculations and Doppler cooling simulations that an atomic rubidium beam with a brightness of $2.1 \\times 10^7 A/(m^2\\,sr\\,eV)$ at a current of 1 nA can be created using a compact 5 cm long 2D magneto-optical compressor which is more than an order of magnitude better than the current state of the art Liquid Metal Ion Source.

  3. Formation of long-range ordered quantum dots arrays in amorphous matrix by ion beam irradiation

    SciTech Connect (OSTI)

    Buljan, M. [Charles University in Prague, Prague 12116 (Czech Republic); Ruder Boskovic Institute, Zagreb 10000 (Croatia); Bogdanovic-Radovic, I.; Karlusic, M.; Desnica, U. V.; Radic, N.; Dubcek, P. [Ruder Boskovic Institute, Zagreb 10000 (Croatia); Drazic, G. [Jozef Stefan Institute, Ljubljana 1000 (Slovenia); Salamon, K. [Institute of Physics, Zagreb 10000 (Croatia); Bernstorff, S. [Sincrotrone Trieste, Basovizza 34012 (Italy); Holy, V. [Charles University in Prague, Prague 12116 (Czech Republic)

    2009-08-10T23:59:59.000Z

    We demonstrate the production of a well ordered three-dimensional array of Ge quantum dots in amorphous silica matrix. The ordering is achieved by ion beam irradiation and annealing of a multilayer film. Structural analysis shows that quantum dots nucleate along the direction of the ion beam used for irradiation, while the mutual distance of the quantum dots is determined by the diffusion properties of the multilayer material rather than the distances between traces of ions that are used for irradiation.

  4. High speed measurements of neutral beam turn-on and impact of beam modulation on measurements of ion density

    SciTech Connect (OSTI)

    Grierson, B. A., E-mail: bgriers@pppl.gov; Grisham, L. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States); Burrell, K. H.; Crowley, B.; Scoville, J. T. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)

    2014-10-15T23:59:59.000Z

    Modulation of neutral beams on tokamaks is performed routinely, enabling background rejection for active spectroscopic diagnostics, and control of injected power and torque. We find that there exists an anomalous initial transient in the beam neutrals delivered to the tokamak that is not accounted for by the accelerator voltage and power supply current. Measurements of the charge-exchange and beam photoemission on the DIII-D tokamak [J. L. Luxon, Nucl. Fusion 42, 614 (2002)] at high speed (200 ?s) reveal that the energy of the beam neutrals is constant, but the density of beam neutrals displays dramatic variation in the first 2–3 ms following beam turn-on. The impact of this beam density variation on inferred ion densities and impurity transport is presented, with suggested means to correct for the anomalous transient.

  5. Ion beam oscillation due to fluctuation of a hot filament driven magnetized plasma

    SciTech Connect (OSTI)

    Imakita, S.; Kasuya, T.; Kimura, Y.; Wada, M. [Graduate School of Engineering, Doshisha University, Kyoto 610-0321 (Japan); Miyamoto, N. [Nissin Ion Equipment Co. Ltd., Kyoto 601-8205 (Japan)

    2010-02-15T23:59:59.000Z

    Ion beam current extracted from a modified Bernas type ion source occasionally exhibits an oscillation at a frequency of several 100 kHz. Increase in the strength of a linear magnetic field induced to the ion source has either decreased or increased the frequency of this oscillation. The frequency showed an increase in proportion to the ion extraction voltage when the frequency decreased with increasing magnetic field. The change of extraction voltage did not affect the frequency when the frequency increased with the increasing magnetic field. Mechanisms causing these oscillations of an ion beam had been investigated.

  6. Numerical study of the characteristics of the ion and fast atom beams in an end-Hall ion source

    SciTech Connect (OSTI)

    Oudini, N. [Universite de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse Cedex 9 (France); Garrigues, L.; Hagelaar, G. J. M.; Boeuf, J. P. [Universite de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse Cedex 9 (France); CNRS, LAPLACE, F-31062 Toulouse (France)

    2012-10-15T23:59:59.000Z

    An end-Hall ion source is a cylindrical magnetized device of few centimeters in length able to generate an ion beam with a current of typically 1 A and ion energies in the range of 100 eV. This ion source does not use acceleration grids, has a relatively large ion beam divergence, and is well suited for ion assisted deposition processes. In this paper, a self-consistent two-dimensional quasi-neutral model of an end-Hall ion source is used to understand the parameters controlling the characteristics of the extracted. The model results underline the role of charge exchange collisions on beam properties. The calculated energy distribution functions reveal the existence of groups of slow ions and fast neutrals. Ion mean energy corresponds to roughly 60% of the discharge voltage, while the root mean square deviation from the mean energy corresponds to about 33% of the discharge voltage, as in experiments. The influence of the position of the electron emitting source on the ion angular distribution is also shown.

  7. Endoscopic Electron-Beam Cancer Therapy | Argonne National Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Endoscopic Electron-Beam Cancer Therapy Technology available for licensing: A successful and cost-effective means of treating cancer in previously inoperable or radiation-sensitive...

  8. Construction of a scattering chamber for ion-beam analysis of environmental materials in undergraduate physics research

    SciTech Connect (OSTI)

    LaBrake, Scott M.; Vineyard, Michael F.; Turley, Colin F.; Moore, Robert D.; Johnson, Christopher [Department of Physics and Astronomy Union College, Schenectady, NY 12308 (United States)

    2013-04-19T23:59:59.000Z

    We have developed a new scattering chamber for ion-beam analysis of environmental materials with the 1.1-MV Pelletron accelerator at the Union College Ion-Beam Analysis Laboratory. The chamber was constructed from a ten-inch, Conflat, multi-port cross and includes a three-axis target manipulator and target ladder assembly, an eight-inch turbo pump, an Amptek X-ray detector, and multiple charged particle detectors. Recent projects performed by our undergraduate research team include proton induced X-ray emission (PIXE) and Rutherford backscattering (RBS) analyses of atmospheric aerosols collected with a nine-stage cascade impactor in Upstate New York. We will describe the construction of the chamber and discuss the results of some commissioning experiments.

  9. Ion-beam apparatus and method for analyzing and controlling integrated circuits

    DOE Patents [OSTI]

    Campbell, Ann N. (Albuquerque, NM); Soden, Jerry M. (Placitas, NM)

    1998-01-01T23:59:59.000Z

    An ion-beam apparatus and method for analyzing and controlling integrated circuits. The ion-beam apparatus comprises a stage for holding one or more integrated circuits (ICs); a source means for producing a focused ion beam; and a beam-directing means for directing the focused ion beam to irradiate a predetermined portion of the IC for sufficient time to provide an ion-beam-generated electrical input signal to a predetermined element of the IC. The apparatus and method have applications to failure analysis and developmental analysis of ICs and permit an alteration, control, or programming of logic states or device parameters within the IC either separate from or in combination with applied electrical stimulus to the IC for analysis thereof. Preferred embodiments of the present invention including a secondary particle detector and an electron floodgun further permit imaging of the IC by secondary ions or electrons, and allow at least a partial removal or erasure of the ion-beam-generated electrical input signal.

  10. Plasma focus ion beam fluence and flux—For various gases

    SciTech Connect (OSTI)

    Lee, S. [Centre for Plasma Research, INTI International University, 71800 Nilai (Malaysia) [Centre for Plasma Research, INTI International University, 71800 Nilai (Malaysia); Institute for Plasma Focus Studies, 32 Oakpark Drive, Chadstone 3148 (Australia); Physics Department, University of Malaya (Malaysia); Saw, S. H. [Centre for Plasma Research, INTI International University, 71800 Nilai (Malaysia) [Centre for Plasma Research, INTI International University, 71800 Nilai (Malaysia); Institute for Plasma Focus Studies, 32 Oakpark Drive, Chadstone 3148 (Australia)

    2013-06-15T23:59:59.000Z

    A recent paper derived benchmarks for deuteron beam fluence and flux in a plasma focus (PF) [S. Lee and S. H. Saw, Phys. Plasmas 19, 112703 (2012)]. In the present work we start from first principles, derive the flux equation of the ion beam of any gas; link to the Lee Model code and hence compute the ion beam properties of the PF. The results show that, for a given PF, the fluence, flux, ion number and ion current decrease from the lightest to the heaviest gas except for trend-breaking higher values for Ar fluence and flux. The energy fluence, energy flux, power flow, and damage factors are relatively constant from H{sub 2} to N{sub 2} but increase for Ne, Ar, Kr and Xe due to radiative cooling and collapse effects. This paper provides much needed benchmark reference values and scaling trends for ion beams of a PF operated in any gas.

  11. Applications of laser produced ion beams to nuclear analysis of materials

    SciTech Connect (OSTI)

    Mima, K.; Azuma, H.; Fujita, K.; Yamazaki, A.; Okuda, C.; Ukyo, Y.; Kato, Y.; Arrabal, R. Gonzalez; Soldo, F.; Perlado, J. M.; Nishimura, H.; Nakai, S. [Graduate School for the Creation of New Photonics Industries, Shizuoka (Japan) and Institute de Fusion Nuclear, Universidad Politecnica de Madrid, Madrid (Spain) and Institute of Laser Engineering, Osaka University, Osaka (Japan); Toyota Central R and D Labs., Inc., Aichi (Japan); Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency (JAEA), Gunnma (Japan); Toyota Central R and D Labs., Inc., Aichi (Japan)

    2012-07-11T23:59:59.000Z

    Laser produced ion beams have unique characteristics which are ultra-short pulse, very low emittance, and variety of nuclear species. These characteristics could be used for analyzing various materials like low Z ion doped heavy metals or ceramics. Energies of laser produced ion beam extend from 0.1MeV to 100MeV. Therefore, various nuclear processes can be induced in the interactions of ion beams with samples. The ion beam driven nuclear analysis has been developed for many years by using various electrostatic accelerators. To explore the applicability of laser ion beam to the analysis of the Li ion battery, a proton beam with the diameter of {approx} 1.0 {mu}m at Takasaki Ion Acceleration for Advanced Radiation Application (TIARA), JAEA was used. For the analysis, the PIGE (Particle-Induced Gamma Ray Emission) is used. The proton beam scans over Li battery electrode samples to diagnose Li density in the LiNi{sub 0.85}Co{sub 0.15}O{sub 2} anode. As the results, PIGE images for Li area density distributions are obtained with the spatial resolution of better than 1.5{mu}m FWHM. By the Li PIGE images, the depth dependence of de-intercalation levels of Li in the anode is obtained. By the POP experiments at TIARA, it is clarified that laser produced ion beam is appropriate for the Li ion battery analysis. 41.85.Lc, 41.75.Jv, 42.62.cf.

  12. Extraction of a steady state electron beam from HCD (hollow cathode discharge) plasmas for EBIS (electron beam ion source) applications

    SciTech Connect (OSTI)

    Hershcovitch, A.; Kovarik, V.; Prelec, K.

    1988-01-01T23:59:59.000Z

    Experiments to extract high brightness electron beams from hollow cathode discharge plasmas are now in progress. A unique feature of these plasmas, which in principle can facilitate the extraction of large current low emittance electron beams, is the existence of a relatively high energy electron population with a very narrow energy spread. This electron population was identified in a self-extraction experiment, which yielded a 35 eV, 600 mA electron beam with parallel energy spread of less than 0.5 eV. Preliminary, crude application of 2.5 kV extraction voltage yielded a steady state electron beam current of 1.2 A. The end result of this endeavor would be an Electron Beam Ion Source (EBIS) with an electron beam current of 6 A. 4 refs., 2 figs.

  13. Large Area Microcorrals and Cavity Formation on Cantilevers using a Focused Ion Beam

    SciTech Connect (OSTI)

    Saraf, Laxmikant V.; Britt, David W.

    2011-09-14T23:59:59.000Z

    We utilize focused ion beam (FIB) to explore various sputtering parameters to form large area microcorrals and cavities on cantilevers. Microcorrals were rapidly created by modifying ion beam blur and overlaps. Modification in FIB sputtering parameters affects the periodicity and shape of corral microstructure. Cantilever deflections show ion beam amorphization effects as a function of sputtered area and cantilever base cavities with or without side walls. The FIB sputtering parameters address a method for rapid creation of a cantilever tensiometer with integrated fluid storage and delivery.

  14. Ion beam analyses of radionuclide migration in heterogeneous rocks

    SciTech Connect (OSTI)

    Alonso, Ursula; Missana, Tiziana; Garcia-Gutierrez, Miguel [CIEMAT, Avda. Complutense 40, Madrid 28040 (Spain); Patelli, Alessandro [CIVEN, Via delle Industrie 5, Venezia-Marghera 30175 (Italy); Rigato, Valentino; Ceccato, Daniele [LNL-INFN, Viale dell' Universita 2, Legnaro-Padova 35020 (Italy)

    2013-07-18T23:59:59.000Z

    The migration of radionuclides (RN) in the environment is a topic of general interest, for its implications on public health, and it is an issue for the long-term safety studies of deep geological repositories (DGR) for high-level radioactive waste. The role played by colloids on RN migration is also of great concern. Diffusion and sorption are fundamental mechanisms controlling RN migration in rocks and many experimental approaches are applied to determine transport parameters for low sorbing RN in homogeneous rocks. However, it is difficult to obtain relevant data for high sorbing RN or colloids, for which diffusion lengths are extremely short, or within heterogeneous rocks, where transport might be different in different minerals. The ion beam techniques Rutherford Backscattering Spectrometry (RBS) and micro-Particle Induced X-Ray Emission ({mu}PIXE), rarely applied in the field, were selected for their micro-analytical potential to study RN diffusion and surface retention within heterogeneous rocks. Main achievements obtained during last 12 years are highlighted.

  15. Overview of Theory and Modeling in the Heavy Ion Fusion Virtual National Laboratory

    E-Print Network [OSTI]

    Davidson, R C; Celata, C M; Cohen, R H; De Hoon, M; Friedman, A; Grote, D P; Henestroza, E; Kaganovich, I D; Lee, E P; Lee, W W; Lund, S M; Olson, C L; Qin, H; Rose, D V; Sharp, W M; Startsev, E A; Tzenov, Stephan I; Vay, J L; Welch, D R; Yu, S S

    2003-01-01T23:59:59.000Z

    This paper presents analytical and simulation studies of intense heavy ion beam propagation, including the injection, acceleration, transport and compression phases, and beam transport and focusing in background plasma in the target chamber. Analytical theory and simulations that support the High Current Experiment (HCX), the Neutralized Transport Experiment (NTX), and the advanced injector development program are being used to provide a basic understanding of the nonlinear beam dynamics and collective processes, and to develop design concepts for the next-step Integrated Beam Experiment (IBX), an Integrated Research Experiment (IRE), and a heavy ion fusion driver. Three-dimensional (3-D) nonlinear perturbative simulations have been applied to collective instabilities driven by beam temperature anisotropy and to two-stream interactions between the beam ions and any unwanted background electrons. Three-dimensional particle-in-cell simulations of the 2 MV Electrostatic Quadrupole (ESQ) injector have clarified t...

  16. Interaction of ion-acoustic solitons with electron beam in warm plasmas with superthermal electrons

    E-Print Network [OSTI]

    Esfandyari-Kalejahi, A R

    2012-01-01T23:59:59.000Z

    Propagation of ion-acoustic solitary waves (IASWs) is studied using the hydrodynamic equations coupled with the Poisson equation in a warm plasma consisting of adiabatic ions and superthermal (Kappa distributed) electrons in presence of an electron-beam component. In the linear limit, the dispersion relation for ion-acoustic (IA) waves is obtained by linearizing of basic equations. On the other hand, in the nonlinear analysis, an energy-balance like equation involving Sagdeev's pseudo-potential is derived in order to investigate arbitrary amplitude IA solitons. The Mach number range is determined in which, propagation and characteristics of IA solitons are analyzed both parametrically and numerically. The variation of amplitude and width of electrostatic (ES) excitations as a result of superthermality (via) and also the physical parameters (ion temperature, soliton speed, electron-beam density and electron-beam velocity) are examined. A typical interaction between IASWs and the electron-beam in plasma is conf...

  17. Space-Charge Limits on the Transport of Ion Beams in a Long Alternating Gradient System

    E-Print Network [OSTI]

    Tiefenback, M.G.

    2011-01-01T23:59:59.000Z

    35j. The output voltage droops in time as the charge on thethe ion gun apertures. Any droop in beam energy re­ sults in0.6 msec (0.15% per /zsec droop) is coupled to the various

  18. Ion-Beam Synthesis of Epitaxial Au Nanocrystals in MgO. | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    relationship to MgO(100). Citation: Thevuthasan S, V Shutthanandan, CM Wang, WJ Weber, W Jiang, AS Cavanagh, J Lian, and LM Wang.2004."Ion-Beam Synthesis of Epitaxial Au...

  19. Ion-beam-induced chemical disorder in GaN. | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    defect formation processes between these layers. Citation: Ishimaru M, Y Zhang, and WJ Weber.2009."Ion-beam-induced chemical disorder in GaN."Journal of Applied Physics...

  20. Neutralized Drift Compression Experiments (NDCX) with a High Intensity Ion Beam

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    a High Intensity Ion Beam P. K. Roy 1* , S. S. Yu 1 , W. L.12 , 043102 (2005). [6] P. K. Roy et al. , Nucl. Instrum.2005), p.4006. [16] P. K. Roy, S. S. Yu, E. Henestroza, A.

  1. Ion Chamber Arrays for the Numi Beam at Fermilab

    E-Print Network [OSTI]

    D. Indurthy; Z. Pavlovic; R. Zwaska; R. Keisler; S. Mendoza; S. Kopp; M. Proga; D. Harris; A. Marchionni; J. Morfin; A. Erwin; H. Ping; C. Velissaris; M. Bishai; M. Diwan; B. Viren; D. Naples; D. Northacker; J. McDonald

    2005-06-26T23:59:59.000Z

    The Neutrinos at the Main Injector (NuMI) beamline will deliver an intense muon neutrino beam by focusing a beam of mesons into a long evacuated decay volume. We have built 4 arrays of ionization chambers to monitor the neutrino beam direction and quality. The arrays are located at 4 stations downstream of the decay volume, and measure the remnant hadron beam and tertiary muons produced along with neutrinos in meson decays.

  2. Shielding analysis for a heavy ion beam chamber with plasma channels for ion transport

    SciTech Connect (OSTI)

    Sawan, M.E.; Peterson, R.R.; Yu, S.

    2000-06-28T23:59:59.000Z

    Neutronics analysis has been performed to assess the shielding requirements for the insulators and final focusing magnets in a modified HYLIFE-II target chamber that utilizes pre-formed plasma channels for heavy ion beam transport. Using 65 cm thick Flibe jet assemblies provides adequate shielding for the electrical insulator units. Additional shielding is needed in front of the final focusing superconducting quadrupole magnets. A shield with a thickness varying between 45 and 90 cm needs to be provided in front of the quadrupole unit. The final laser mirrors located along the channel axis are in the direct line-of-sight of source neutrons. Neutronics calculations were performed to determine the constraints on the placement of these mirrors to be lifetime components.

  3. Ion Beam Deposition of Thin Films: Growth Processes and Nanostructure Formation

    SciTech Connect (OSTI)

    Hofsaess, Hans C. [II. Physikalisches Institut, Universitaet Goettingen, Friedrich-Hund-Platz 1, D-37077 Goettingen (Germany)

    2004-12-01T23:59:59.000Z

    Ion beam deposition is a process far from thermodynamic equilibrium and is in particular suited to grow metastable thin films with diamond-like properties, such as tetrahedral amorphous carbon (ta-C) and cubic boron nitride (c-BN). In this contribution the atomistic description of the deposition and growth processes are reviewed and compared to experimental results, obtained from mass selected ion beam deposition. The focus will be set to the nucleation and growth processes of boron nitride as a model system for ion based thin film formation. Furthermore, recent examples for nanostructure formation in ion deposited compound thin films will be presented. Ion beam deposited metal-carbon nano-composite thin films exhibit a variety of different morphologies such as rather homogeneous nanocluster distributions embedded in an a-C matrix, but also the self-organized formation of nanoscale multilayer structures.

  4. Experimental observation of ion beams in the Madison Helicon eXperiment

    SciTech Connect (OSTI)

    Wiebold, Matt; Sung, Yung-Ta; Scharer, John E. [Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

    2011-06-15T23:59:59.000Z

    Argon ion beams up to E{sub b} = 165 eV at P{sub rf} = 500 W are observed in the Madison Helicon eXperiment (MadHeX) helicon source with a magnetic nozzle. A two-grid retarding potential analyzer (RPA) is used to measure the ion energy distribution, and emissive and rf-filtered Langmuir probes measure the plasma potential, electron density, and temperature. The supersonic ion beam (M = v{sub i}/c{sub s} up to 5) forms over tens of Debye lengths and extends spatially for a few ion-neutral charge-exchange mean free paths. The parametric variation of the ion beam energy is explored, including flow rate, rf power, and magnetic field dependence. The beam energy is equal to the difference in plasma potentials in the Pyrex chamber and the grounded expansion chamber. The plasma potential in the expansion chamber remains near the predicted eV{sub p} {approx} 5kT{sub e} for argon, but the upstream potential is much higher, likely due to wall charging, resulting in accelerated ion beam energies E{sub b} = e[V{sub beam} - V{sub plasma}] > 10kT{sub e}.

  5. Bulk ion acceleration and particle heating during magnetic reconnection in a laboratory plasmaa)

    E-Print Network [OSTI]

    Ji, Hantao

    Bulk ion acceleration and particle heating during magnetic reconnection in a laboratory plasmaa January 2014; accepted 20 February 2014; published online 7 May 2014) Bulk ion acceleration and particle-plane (Hall) electric field plays a key role in ion heating and acceleration. The electrostatic potential

  6. Experimental verification of an ion-induced focus model for the recirculating electron beam injector

    SciTech Connect (OSTI)

    Poukey, J.W.; Mazarakis, M.G. (Sandia National Laboratories, Albuquerque, NM (USA)); Platt, R.C. (Science Applications International, Albuquerque, NM (USA))

    1990-10-22T23:59:59.000Z

    We present a model for the operation of a particular type of electron beam diode used in the Sandia Recirculating Linear Accelerator system. The critical element of the model is ion emission from the anode aperture, which neutralizes enough beam space charge to permit focusing. Recent experimental results are shown which support the model in several respects.

  7. Transport of ion beam in an annular magnetically expanding helicon double layer thruster

    SciTech Connect (OSTI)

    Zhang, Yunchao, E-mail: yunchao.zhang@anu.edu.au; Charles, Christine; Boswell, Rod [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, The Australian National University, Bldg 60, Mills Road, ACT 0200 (Australia)

    2014-06-15T23:59:59.000Z

    An ion beam generated by an annular double layer has been measured in a helicon thruster, which sustains a magnetised low-pressure (5.0?×?10{sup ?4}?Torr) argon plasma at a constant radio-frequency (13.56 MHz) power of 300?W. After the ion beam exits the annular structure, it merges into a solid centrally peaked structure in the diffusion chamber. As the annular ion beam moves towards the inner region in the diffusion chamber, a reversed-cone plasma wake (with a half opening angle of about 30°) is formed. This process is verified by measuring both the radial and axial distributions of the beam potential and beam current. The beam potential changes from a two-peak radial profile (maximum value???30?V, minimum value???22.5?V) to a flat (?28?V) along the axial direction; similarly, the beam current changes from a two-peak to one-peak radial profile and the maximum value decreases by half. The inward cross-magnetic-field motion of the beam ions is caused by a divergent electric field in the source. Cross-field diffusion of electrons is also observed in the inner plume and is determined as being of non-ambipolar origin.

  8. INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMS

    E-Print Network [OSTI]

    Sharp, W. M.

    2011-01-01T23:59:59.000Z

    HIFAN 1830 INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMSAC02-05CH11231. INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION467 (1992). [38] R. W. Moir, Fusion Tech. 25, 5 (1994) [39

  9. Multiple-ion-beam time-of-flight mass spectrometer Andreas Rohrbacher and Robert E. Continettia)

    E-Print Network [OSTI]

    Continetti, Robert E.

    /ionization and the molecular ions of two different proteins myoglobin and lysozyme , created by matrix assisted laser,7 and matrix assisted desorption and ionization MALDI 8­11 have become avail- able to allow the mass the samples with a robot- driven capillary,15 a scanning ion beam,16 or spatial resolu- tion was achieved

  10. Magnetic shielding of walls from the unmagnetized ion beam in a Hall thruster

    SciTech Connect (OSTI)

    Mikellides, Ioannis G.; Katz, Ira; Hofer, Richard R.; Goebel, Dan M. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)] [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)

    2013-01-14T23:59:59.000Z

    We demonstrate by numerical simulations and experiments that the unmagnetized ion beam formed in a Hall thruster can be controlled by an applied magnetic field in a manner that reduces by 2-3 orders of magnitude deleterious ion bombardment of the containing walls. The suppression of wall erosion in Hall thrusters to such low levels has remained elusive for decades.

  11. High energy heavy ion jets emerging from laser plasma generated by long pulse laser beams from

    E-Print Network [OSTI]

    in inter- action processes of short and ultra-short laser pulses with matter. Ion generation from laserHigh energy heavy ion jets emerging from laser plasma generated by long pulse laser beams from the NHELIX laser system at GSI G. SCHAUMANN,1 M.S. SCHOLLMEIER,1 G. RODRIGUEZ-PRIETO,2 A. BLAZEVIC,2 E

  12. Chapter 2 Deuterium Reaction with C(100): IonBeam Scattering Experiment

    E-Print Network [OSTI]

    Goddard III, William A.

    ­beam scattering techniques are easily calibrated by compari­ #12; 28 son to ion­implanted standards, and nuclear of 1560 ffi C from time­of­flight scattering and recoil­ion spectroscopy (TOF­SARS). However, Chin et al

  13. Focusing of intense and divergent ion beams in a magnetic mass analyzer

    SciTech Connect (OSTI)

    Jianlin, Ke; Changgeng, Zhou; Rui, Qiu; Yonghong, Hu [Institute of Nuclear Physics and Chemistry, CAEP, 621900 Mianyang (China)

    2014-07-15T23:59:59.000Z

    A magnetic mass analyzer is used to determine the beam composition of a vacuum arc ion source. In the analyzer, we used the concentric multi-ring electrodes to focus the intense and divergent ion beams. We describe the principle, design, and the test results of the focusing device. The diameter of the beam profile is less than 20 mm when the accelerating voltage is 30 kV and the focusing voltage is about 2.0 kV. The focusing device has been successfully used in the magnetic mass analyzer to separate Ti{sup +}, Ti{sup 2+}, and Ti{sup 3+}.

  14. Development of hollow electron beams for proton and ion collimation

    SciTech Connect (OSTI)

    Stancari, G.; Drozhdin, A.I.; Kuznetsov, G.; Shiltsev, V.; Still, D.A.; Valishev, A.; Vorobiev, L.G.; /Fermilab; Assmann, R.; /CERN; Kabantsev, A.; /UC, San Diego

    2010-06-01T23:59:59.000Z

    Magnetically confined hollow electron beams for controlled halo removal in high-energy colliders such as the Tevatron or the LHC may extend traditional collimation systems beyond the intensity limits imposed by tolerable material damage. They may also improve collimation performance by suppressing loss spikes due to beam jitter and by increasing capture efficiency. A hollow electron gun was designed and built. Its performance and stability were measured at the Fermilab test stand. The gun will be installed in one of the existing Tevatron electron lenses for preliminary tests of the hollow-beam collimator concept, addressing critical issues such as alignment and instabilities of the overlapping proton and electron beams.

  15. Theoretical and Experimental Studies of the Extracted MCI Beam from an ECR Ion Source

    SciTech Connect (OSTI)

    Sun, L.T.; Cao, Y.; Zhao, H.W.; Guo, X.H.; Zhang, Z.M.; Feng, Y.C.; Li, J.Y.; Ma, L.; Li, J.; Zhao, H.Y.; He, W.; Li, X.X. [Institute of Modern Physics (IMP), Chinese Academy of Sciences, Lanzhou (China); Hitz, D.; Girard, A. [CEA-Grenoble, Departement de Recherche Fondamentale sur la Matiere Condensee, Service des Basses Temperatures, 17 Rue des Martyrs, 38054 Grenoble Cedex 9 (France)

    2005-03-15T23:59:59.000Z

    With the development of Electron Cyclotron Resonance Ion Source (ECRIS), very high performance ECRIS nowadays have been set up one by one around the world, such as the GTS in Grenoble, SERSE in Catania, LECR3 in Lanzhou and etc, which can produce very intense Multiply Charged Ion (MCI) beam. But till now, the study of the extracted MCI beam from an ECRIS remains open. In this article, we present a theoretical and experimental study of the extracted MCI beam. In the theoretical part, the influences of the extraction system on the extracted ion beam quality are mainly analyzed. The aspects that have influences on the extracted ion beam quality have been analyzed. With the instruction of the analysis, the PBGUNS code is used to simulate the influences of some important aspects concerning the extraction system. The influences of the extraction system geometry design, magnetic field, and the space charge effect will be detailedly presented in this article. In the experimental part, with an Electric-Sweep Scanner (ESS) emittance detection system, the influences on the extracted ion beam emittance of some typical parameters of ECRIS have been researched, such as the injected RF power, the RF frequency, the magnetic field and etc. The obtained results and the corresponding explanations are presented. Some of the results are well in accord with some empirical laws, but some other results seem to be disputed.

  16. Optimization of ion-atomic beam source for deposition of GaN ultrathin films

    SciTech Connect (OSTI)

    Mach, Jind?ich, E-mail: mach@fme.vutbr.cz; Kolíbal, Miroslav; Zlámal, Jakub; Voborny, Stanislav; Bartošík, Miroslav; Šikola, Tomáš [Institute of Physical Engineering, Brno University of Technology, Technická 2, 616 69 Brno (Czech Republic); CEITEC BUT, Brno University of Technology, Technická 10, 61669 Brno (Czech Republic); Šamo?il, Tomáš [Institute of Physical Engineering, Brno University of Technology, Technická 2, 616 69 Brno (Czech Republic)

    2014-08-15T23:59:59.000Z

    We describe the optimization and application of an ion-atomic beam source for ion-beam-assisted deposition of ultrathin films in ultrahigh vacuum. The device combines an effusion cell and electron-impact ion beam source to produce ultra-low energy (20–200 eV) ion beams and thermal atomic beams simultaneously. The source was equipped with a focusing system of electrostatic electrodes increasing the maximum nitrogen ion current density in the beam of a diameter of ?15 mm by one order of magnitude (j ? 1000 nA/cm{sup 2}). Hence, a successful growth of GaN ultrathin films on Si(111) 7 × 7 substrate surfaces at reasonable times and temperatures significantly lower (RT, 300?°C) than in conventional metalorganic chemical vapor deposition technologies (?1000?°C) was achieved. The chemical composition of these films was characterized in situ by X-ray Photoelectron Spectroscopy and morphology ex situ using Scanning Electron Microscopy. It has been shown that the morphology of GaN layers strongly depends on the relative Ga-N bond concentration in the layers.

  17. Selective compositional mixing in GaAs/AIGaAs superlattice induced by low dose Si focused ion beam implantation

    E-Print Network [OSTI]

    Steckl, Andrew J.

    of the mixing process was observed at 100 keV implantation energy, with a "pinch-off" (more heavily mixed ion beam (FIB) implantation technology has been especially attractive in this application, since/or transfer technology, the lateral profiles of the ion beam (and of the ions implanted in the solid

  18. Production of beams of neutron-rich nuclei between Ca and Ni using the ion-guide technique

    SciTech Connect (OSTI)

    Perajarvi, K.; Cerny, J.; Hager, U.; Hakala, J.; Huikari, J.; Jokinen, A.; Karvonen, P.; Kurpeta, J.; Lee, D.; Moore, I.; Penttila, H.; Popov, A.; Aysto, J.

    2004-09-28T23:59:59.000Z

    Since several elements between Z = 20-28 are refractory in their nature, their neutron-rich isotopes are rarely available as low energy Radioactive Ion Beams (RIB) in ordinary Isotope Separator On-Line facilities [1-4]. These low energy RIBs would be especially interesting to have available under conditions which allow high-resolution beta-decay spectroscopy, ion-trapping and laser-spectroscopy. As an example, availability of these beams would open a way for research which could produce interesting and important data on neutron-rich nuclei around the doubly magic {sup 78}Ni. One way to overcome the intrinsic difficulty of producing these beams is to rely on the chemically unselective Ion Guide Isotope Separator On-Line (IGISOL) technique [5]. Quasi- and deep-inelastic reactions, such as {sup 197}Au({sup 65}Cu,X)Y, could be used to produce these nuclei in existing IGISOL facilities, but before they can be successfully incorporated into the IGISOL concept their kinematics must be well understood. Therefore the reaction kinematics part of this study was first performed at the Lawrence Berkeley National Laboratory using its 88'' cyclotron and, based on those results, a specialized target chamber was built[6]. The target chamber shown in Fig. 1 was recently tested on-line at the Jyvaaskylaa IGISOL facility. Yields of mass-separated radioactive projectile-like species such as {sup 62,63}Co are about 0.8 ions/s/pnA, corresponding to about 0.06 % of the total IGISOL efficiency for the products that hit the Ni-degrader. (The current maximum 443 MeV {sup 65}Cu beam intensity at Jyvaaskylaa is about 20 pnA.) This total IGISOL efficiency is a product of two coupled loss factors, namely inadequate thermalization and the intrinsic IGISOL efficiency. In our now tested chamber, about 9 % of the Co recoils are thermalized in the owing He gas (p{sub He}=300 mbar) and about 0.7 % of them are converted into the mass-separated ion beams. In the future, both of these physical/chemical conditions can be suppressed by introducing Ar as a buffer gas and by relying on selective laser re-ionization. This combination will produce isobarically pure beams and it will increase the existing yields by at least a factor of 100, making this overall approach to the study of neutron rich nuclei even more attractive.

  19. Nonlinear Plasma Waves Excitation by Intense Ion Beams in Background Plasma

    SciTech Connect (OSTI)

    Igor D. Kaganovich; Edward A. Startsev; Ronald C. Davidson

    2004-04-15T23:59:59.000Z

    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 {tau}{sub b} is much longer than the electron plasma period 2{pi}/{omega}{sub p}, where {omega}{sub p} = (4{pi}e{sup 2}n{sub p}/m){sup 1/2} is the electron plasma frequency and n{sub 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.

  20. LEEM investigations of clean surfaces driven by energetic ion beams

    SciTech Connect (OSTI)

    Abbamonte, Peter M. [University of Illinois] University of Illinois

    2013-04-24T23:59:59.000Z

    The original purpose of this award was to use low?energy electron microscopy (LEEM) to explore the dynamics of surfaces of clean single crystal surfaces when driven by a beam of energetic ions. The goal was to understand the nanoscience of hyperthermal growth, surface erosion by sublimation and irradiation, operation of surface sinks in irradiated materials, diffusion on driven surfaces, and the creation of structural patterns. This project was based on a novel LEEM system constructed by C. P. Flynn, which provided real?time imaging of surface dynamics by scattering low energy electrons. With the passing of Prof. Flynn in late 2011, this project was completed under a slightly different scope by constructing a low?energy, inelastic electron scattering (?EELS?) instrument. Consistent with Flynn?s original objectives for his LEEM system, this device probes the dynamics of crystal surfaces. However the measurements are not carried out in real time, but instead are done in the frequency domain, through the energy lost from the probe electrons. The purpose of this device is to study the collective bosonic excitations in a variety of materials, including high temperature superconductors, topological insulators, carbon allotropes including (but not limited to) graphene, etc. The ultimate goal here is to identify the bosons that mediate interactions in these and other materials, with hopes of shedding light on the origin of many exotic phenomena including high temperature superconductivity. We completed the construction of a low?energy EELS system that operates with an electron kinetic energy of 7 - 10 eV. With this instrument now running, we hope to identify, among other things, the bosons that mediate pairing in high temperature superconductors. Using this instrument, we have already made our first discovery. Studying freshly cleaved single crystals of Bi{sub 2}Se{sub 3}, which is a topological insulator, we have observed a surface excitation at an energy loss of ~ 90 meV. This excitation disperses quadratically, exhibits a critical momentum of q{sub c} = 0.11 ?{sup ?1}, and may be identified as the surface collective mode of the helical Dirac liquid. To make a stronger connection between the behavior of this excitation and the known surface physics of Bi{sub 2}Se{sub 3}, we are carrying out a doping?dependent study, as a function of Se vacancy content, of this excitation. From this study we will be able to quantify the strength of interactions in the spin?polarized surface states in a manner analogous to our past work on graphene.

  1. Investigation of effect of solenoid magnet on emittances of ion beam from laser ablation plasma

    SciTech Connect (OSTI)

    Ikeda, Shunsuke, E-mail: shunsuke.ikeda@riken.jp; Sekine, Megumi [Tokyo Institute of Technology, Yokohama, Kanagawa (Japan) [Tokyo Institute of Technology, Yokohama, Kanagawa (Japan); Riken, Wako, Saitama (Japan); Romanelli, Mark [Cornell University, Ithaca, New York 14850 (United States)] [Cornell University, Ithaca, New York 14850 (United States); Cinquegrani, David [University of Michigan, Ann Arbor, Michigan 48109 (United States)] [University of Michigan, Ann Arbor, Michigan 48109 (United States); Kumaki, Masafumi [Waseda University, Shinjuku, Tokyo (Japan)] [Waseda University, Shinjuku, Tokyo (Japan); Fuwa, Yasuhiro [Kyoto University, Uji, Kyoto (Japan)] [Kyoto University, Uji, Kyoto (Japan); Kanesue, Takeshi; Okamura, Masahiro [Brookhaven National Laboratory, Upton, New York 11973 (United States)] [Brookhaven National Laboratory, Upton, New York 11973 (United States); Horioka, Kazuhiko [Tokyo Institute of Technology, Yokohama, Kanagawa (Japan)] [Tokyo Institute of Technology, Yokohama, Kanagawa (Japan)

    2014-02-15T23:59:59.000Z

    A magnetic field can increase an ion current of a laser ablation plasma and is expected to control the change of the plasma ion current. However, the magnetic field can also make some fluctuations of the plasma and the effect on the beam emittance and the emission surface is not clear. To investigate the effect of a magnetic field, we extracted the ion beams under three conditions where without magnetic field, with magnetic field, and without magnetic field with higher laser energy to measure the beam distribution in phase space. Then we compared the relations between the plasma ion current density into the extraction gap and the Twiss parameters with each condition. We observed the effect of the magnetic field on the emission surface.

  2. INDEPENDENT VERIFICATION SURVEY OF THE HIGH FLUX BEAM REACTOR DECOMMISSIONING PROJECT OUTSIDE AREAS BROOKHAVEN NATIONAL LABORATORY UPTON, NEW YORK

    SciTech Connect (OSTI)

    P.C. Weaver

    2010-12-15T23:59:59.000Z

    5098-SR-03-0 FINAL REPORT- INDEPENDENT VERIFICATION SURVEY OF THE HIGH FLUX BEAM REACTOR DECOMMISSIONING PROJECT OUTSIDE AREAS, BROOKHAVEN NATIONAL LABORATORY

  3. EIS-0291: High Flux Beam Reactor (HFBR) Transition Project at the Brookhaven National Laboratory, Upton, New York

    Broader source: Energy.gov [DOE]

    The EIS evaluates the range of reasonable alternatives and their impacts regarding the future management of the High Flux Beam Reactor (HFBR) at Brookhaven National Laboratory (BNL).

  4. Beam Ion Instability in ILC Damping Ring with Multi-Gas Species

    SciTech Connect (OSTI)

    Wang, Lanfa; Pivi, Mauro; /SLAC

    2012-05-30T23:59:59.000Z

    Ion induced beam instability is one critical issue for the electron damping ring of the International Linear Collider (ILC) due to its ultra small emittance of 2 pm. The beam ion instability with various beam filling patterns for the latest lattice DTC02 is studied using PIC code. The code has been benchmarked with SPEAR3 experimental data and there is a good agreement between the simulation and observations. It uses the optics from MAD and can handle arbitrary beam filling pattern and vacuum. Different from previous studies, multi-gas species and exact beam filling patterns have been modeled simultaneously in the study. This feature makes the study more realistic. Analyses have been done to compare with the simulations.

  5. DMSE Electron Beam Instruments Facility | The Ames Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisitingContract Management Fermi SitePART I SECTION ADMSE Electron Beam Instruments

  6. Short-Pulse Beam Transport Tube - Laboratory for Laser Energetics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch > TheNuclearHomelandMultivariate Metal-OrganicPulse Beam Transport Tube -

  7. Ion boundary conditions in semi-infinite fluid models of electron beam-plasma interaction

    SciTech Connect (OSTI)

    Levko, Dmitry [LAPLACE (Laboratoire Plasma et Conversion d'Energie), Universite de Toulouse, UPS, INPT Toulouse, 118 route de Narbonne, F-31062 Toulouse cedex 9 (France)

    2014-10-15T23:59:59.000Z

    The modified Bohm criterion is derived for the plasma consisting of the monoenergetic electron beam and thermal electrons. This criterion allows us to define the accurate ion boundary conditions for semi-infinite collisionless fluid models of electron beam–plasma interaction. In the absence of electron beam, these boundary conditions give the classical sheath parameters. When the monoenergetic electron beam propagates through the plasma, the fluid model with proposed boundary conditions gives the results, which are in qualitative agreement with the results obtained earlier in M. Sharifian and B. Shokri, Phys. Plasmas 14, 093503 (2007). However, dynamics and parameters of the plasma sheath are different.

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

    SciTech Connect (OSTI)

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

    2010-04-28T23:59:59.000Z

    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 background plasma. If controlled, this physical effect can be used for optimized beam transport over long distances.

  9. Ion Chambers for Monitoring the NuMI Neutrino Beam at FNAL

    E-Print Network [OSTI]

    D. Indurthy; R. Keisler; S. Kopp; S. Mendoza; M. Proga; Z. Pavlovich; R. Zwaska; D. Harris; A. Marchionni; J. Morfin; A. Erwin; H. Ping; C. Velissaris; D. Naples; D. Northacker; J. McDonald; M. Diwan; B. Viren

    2004-05-05T23:59:59.000Z

    The Neutrinos at the Main Injector (NuMI) beamline will deliver an intense muon neutrino beam by focusing a beam of mesons into a long evacuated decay volume. The beam must be steered with 1 mRad angular accuracy toward the Soudan Underground Laboratory in northern Minnesota. We have built 4 arrays of ionization chambers to monitor the neutrino beam direction and quality. The arrays are located at 4 stations downstream of the decay volume, and measure the remnant hadron beam and tertiary muons produced along with neutrinos in meson decays. We review how the monitors will be used to make beam quality measurements, and as well we review chamber construction details, radiation damage testing, calibration, and test beam results.

  10. Investigation of ISIS and Brookhaven National Laboratory ion source electrodes after extended operation

    SciTech Connect (OSTI)

    Lettry, J.; Gerardin, A.; Pereira, H.; Sgobba, S. [CERN, 1211 Geneva 23 (Switzerland); Alessi, J. [BNL, P.O. Box 5000, Upton, New York 11973-5000 (United States); Faircloth, D. [RAL, Harwell Oxford, Didcot OX11 0QX (United Kingdom); Kalvas, T. [University of Jyvaskyla, P.O.Box 35, FI-40014 (Finland)

    2012-02-15T23:59:59.000Z

    Linac4 accelerator of Centre Europeen de Recherches Nucleaires is under construction and a RF-driven H{sup -} ion source is being developed. The beam current requirement for Linac4 is very challenging: 80 mA must be provided. Cesiated plasma discharge ion sources such as Penning or magnetron sources are also potential candidates. Accelerator ion sources must achieve typical reliability figures of 95% and above. Investigating and understanding the underlying mechanisms involved with source failure or ageing is critical when selecting the ion source technology. Plasma discharge driven surface ion sources rely on molybdenum cathodes. Deformation of the cathode surfaces is visible after extended operation periods. A metallurgical investigation of an ISIS ion source is presented. The origin of the deformation is twofold: Molybdenum sputtering by cesium ions digs few tenths of mm cavities while a growth of molybdenum is observed in the immediate vicinity. The molybdenum growth under hydrogen atmosphere is hard and loosely bound to the bulk. It is, therefore, likely to peel off and be transported within the plasma volume. The observation of the cathode, anode, and extraction electrodes of the magnetron source operated at BNL for two years are presented. A beam simulation of H{sup -}, electrons, and Cs{sup -} ions was performed with the IBSimu code package to qualitatively explain the observations. This paper describes the operation conditions of the ion sources and discusses the metallurgical analysis and beam simulation results.

  11. Investigation of ISIS and Brookhaven National Laboratory ion source electrodes after extended operation

    SciTech Connect (OSTI)

    Lettry J.; Alessi J.; Faircloth, D.; Gerardin, A.; Kalvas, T.; Pereira, H.; Sgobba, S.

    2012-02-23T23:59:59.000Z

    Linac4 accelerator of Centre Europeen de Recherches Nucleaires is under construction and a RF-driven H{sup -} ion source is being developed. The beam current requirement for Linac4 is very challenging: 80 mA must be provided. Cesiated plasma discharge ion sources such as Penning or magnetron sources are also potential candidates. Accelerator ion sources must achieve typical reliability figures of 95% and above. Investigating and understanding the underlying mechanisms involved with source failure or ageing is critical when selecting the ion source technology. Plasma discharge driven surface ion sources rely on molybdenum cathodes. Deformation of the cathode surfaces is visible after extended operation periods. A metallurgical investigation of an ISIS ion source is presented. The origin of the deformation is twofold: Molybdenum sputtering by cesium ions digs few tenths of mm cavities while a growth of molybdenum is observed in the immediate vicinity. The molybdenum growth under hydrogen atmosphere is hard and loosely bound to the bulk. It is, therefore, likely to peel off and be transported within the plasma volume. The observation of the cathode, anode, and extraction electrodes of the magnetron source operated at BNL for two years are presented. A beam simulation of H{sup -}, electrons, and Cs{sup -} ions was performed with the IBSimu code package to qualitatively explain the observations. This paper describes the operation conditions of the ion sources and discusses the metallurgical analysis and beam simulation results.

  12. Sub-10-nm lithography with light-ion beams

    E-Print Network [OSTI]

    Winston, Donald, Ph. D. Massachusetts Institute of Technology

    2012-01-01T23:59:59.000Z

    Scanning-electron-beam lithography (SEBL) is the workhorse of nanoscale lithography in part because of the high brightness of the Schottky source of electrons, but also benefiting from decades of incremental innovation and ...

  13. Intense Ion Beam for Warm Dense Matter Physics

    E-Print Network [OSTI]

    Heimbucher, Lynn

    2008-01-01T23:59:59.000Z

    waveform and there are voltage oscillations. Before reachingbunching of the beam. Voltage oscillations in the diode alsoThe period T of the voltage oscillation must be t a < T < t

  14. Issues concerning high current lower energy electron beams required for ion cooling between EBIS LINAC and booster

    SciTech Connect (OSTI)

    Hershcovitch,A.

    2009-03-01T23:59:59.000Z

    Some issues, regarding a low energy high current electron beam that will be needed for electron beam cooling to reduce momentum of gold ions exiting the EBIS LINAC before injection into the booster, are examined. Options for propagating such an electron beam, as well as the effect of neutralizing background plasma on electron and ion beam parameters are calculated. Computations and some experimental data indicate that none of these issues is a show stopper.

  15. Effective shielding to measure beam current from an ion source

    SciTech Connect (OSTI)

    Bayle, H., E-mail: bayle@bergoz.com [Bergoz Instrumentation, Saint-Genis-Pouilly (France); Delferrière, O.; Gobin, R.; Harrault, F.; Marroncle, J.; Senée, F.; Simon, C.; Tuske, O. [CEA, Saclay (France)] [CEA, Saclay (France)

    2014-02-15T23:59:59.000Z

    To avoid saturation, beam current transformers must be shielded from solenoid, quad, and RFQ high stray fields. Good understanding of field distribution, shielding materials, and techniques is required. Space availability imposes compact shields along the beam pipe. This paper describes compact effective concatenated magnetic shields for IFMIF-EVEDA LIPAc LEBT and MEBT and for FAIR Proton Linac injector. They protect the ACCT Current Transformers beyond 37 mT radial external fields. Measurements made at Saclay on the SILHI source are presented.

  16. H-mode accelerating structures with PMQ focusing for low-beta ion beams

    SciTech Connect (OSTI)

    Kurennoy, Sergey S [Los Alamos National Laboratory; O' Hara, James F [Los Alamos National Laboratory; Olivas, Eric R [Los Alamos National Laboratory; Rybarcyk, Lawrence J [Los Alamos National Laboratory

    2010-01-01T23:59:59.000Z

    We are developing high-efficiency normal-conducting RF accelerating structures based on inter-digital H-mode (IH) cavities and the transverse beam focusing with permanent-magnet quadrupoles (PMQ), for beam velocities in the range of a few percent of the speed of light. Such IH-PMQ accelerating structures following a short RFQ can be used in the front end of ion linacs or in stand-alone applications, e.g. a compact deuteron-beam accelerator up to the energy of several MeV. Results of combined 3-D modeling for a full IH-PMQ accelerator tank - electromagnetic computations, beam-dynamics simulations with high currents, and thermal-stress analysis - are presented. The accelerating field profile in the tank is tuned to provide the best beam propagation using coupled iterations of electromagnetic and beam-dynamics modeling. A cold model of the IH-PMQ tank is being manufactured.

  17. JCESR: Moving Beyond Lithium-Ion | Argonne National Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    JCESR: Moving Beyond Lithium-Ion Share Topic Energy Energy usage Energy storage Batteries Browse By - Any - Energy -Energy efficiency --Vehicles ---Alternative fuels ---Automotive...

  18. Surface Smoothing of Compound Semiconductor Substrates with Gas Cluster Ion Beams

    SciTech Connect (OSTI)

    Houzumi, S.; Toyoda, N.; Yamada, I. [Laboratory of Advanced Science and Technology for Industry, Himeji Institute of Technology, 3-1-2 Kouto, Kamigori, Ako-gun, Hyogo, 678-1205 (Japan)

    2003-08-26T23:59:59.000Z

    Surface smoothing by gas cluster ion beams (GCIB) was studied for compound semiconductor such as GaN and SiC. Average cluster size of Ar cluster ions was 2000atoms/cluster measured by time of flight (TOF). Since the total acceleration energy was 20keV, the energy per atom was 10eV/atom. This low-energy characteristic of gas cluster ion beams is desirable for compound semiconductors. GCIB irradiation was employed to remove the scratches of the mechanically polished SiC surface. After irradiation at acceleration energy of 15keV, the scratches was completry removed. The GaN film with initial average roughness of 4nm was also smoothed to that of 1.4nm by Ar cluster ion beams. Furthermore SiC substrates were irradiated with SF6 cluster ions. The sputtering yield of SiC with SF6 cluster ions was enhanced almost 3 times than that with Ar cluster ions.

  19. Ion-beam treatment to prepare surfaces of p-CdTe films

    DOE Patents [OSTI]

    Gessert, Timothy A. (Conifer, CO)

    2001-01-01T23:59:59.000Z

    A method of making a low-resistance electrical contact between a p-CdTe layer and outer contact layers by ion beam processing comprising: a) placing a CdS/CdTe device into a chamber and evacuating the chamber; b) orienting the p-CdTe side of the CdS/CdTe layer so that it faces apparatus capable of generating Ar atoms and ions of preferred energy and directionality; c) introducing Ar and igniting the area of apparatus capable of generating Ar atoms and ions of preferred energy and directionality in a manner so that during ion exposure, the source-to-substrate distance is maintained such that it is less than the mean-free path or diffusion length of the Ar atoms and ions at the vacuum pressure; d) allowing exposure of the p-CdTe side of the device to said ion beam for a period less than about 5 minutes; and e) imparting movement to the substrate to control the real uniformity of the ion-beam exposure on the p-CdTe side of the device.

  20. Channeling Effect in Polycrystalline Deuterium-Saturated CVD Diamond Target Bombarded by Deuterium Ion Beam

    E-Print Network [OSTI]

    Bagulya, A V; Negodaev, M A; Rusetskii, A S; Chubenko, A P; Ralchenko, V G; Bolshakov, A P

    2014-01-01T23:59:59.000Z

    At the ion accelerator HELIS at the LPI, the neutron yield is investigated in DD reactions within a polycrystalline deuterium-saturated CVD diamond, during an irradiation of its surface by a deuterium ion beam with the energy less than 30 keV. The measurements of the neutron flux in the beam direction are performed in dependence on the target angle, \\b{eta}, with respect to the beam axis. These measurements are performed using a multichannel detector based on He3 counters. A significant anisotropy in neutron yield is observed, it was higher by a factor of 3 at \\b{eta}=0 compared to that at \\b{eta} = +-45{\\deg}. The possible reasons for the anisotropy, including ion channeling, are discussed.

  1. Channeling Effect in Polycrystalline Deuterium-Saturated CVD Diamond Target Bombarded by Deuterium Ion Beam

    E-Print Network [OSTI]

    A. V. Bagulya; O. D. Dalkarov; M. A. Negodaev; A. S. Rusetskii; A. P. Chubenko; V. G. Ralchenko; A. P. Bolshakov

    2014-09-08T23:59:59.000Z

    At the ion accelerator HELIS at the LPI, the neutron yield is investigated in DD reactions within a polycrystalline deuterium-saturated CVD diamond, during an irradiation of its surface by a deuterium ion beam with the energy less than 30 keV. The measurements of the neutron flux in the beam direction are performed in dependence on the target angle, \\b{eta}, with respect to the beam axis. These measurements are performed using a multichannel detector based on He3 counters. A significant anisotropy in neutron yield is observed, it was higher by a factor of 3 at \\b{eta}=0 compared to that at \\b{eta} = +-45{\\deg}. The possible reasons for the anisotropy, including ion channeling, are discussed.

  2. Emulation of reactor irradiation damage using ion beams

    SciTech Connect (OSTI)

    G. S. Was; Z. Jiao; E. Beckett; A. M. Monterrosa; O. Anderoglu; B. H. Sencer; M. Hackett

    2014-10-01T23:59:59.000Z

    The continued operation of existing light water nuclear reactors and the development of advanced nuclear reactor depend heavily on understanding how damage by radiation to levels degrades materials that serve as the structural components in reactor cores. The first high dose ion irradiation experiments on a ferritic-martensitic steel showing that ion irradiation closely emulates the full radiation damage microstructure created in-reactor are described. Ferritic-martensitic alloy HT9 (heat 84425) in the form of a hexagonal fuel bundle duct (ACO-3) accumulated 155 dpa at an average temperature of 443°C in the Fast Flux Test Facility (FFTF). Using invariance theory as a guide, irradiation of the same heat was conducted using self-ions (Fe++) at 5 MeV at a temperature of 460°C and to a dose of 188 displacements per atom. The void swelling was nearly identical between the two irradiations and the size and density of precipitates and loops following ion irradiation are within a factor of two of those for neutron irradiation. The level of agreement across all of the principal microstructure changes between ion and reactor irradiations establishes the capability of tailoring ion irradiations to emulate the reactor-irradiated microstructure.

  3. Development of the front end test stand and vessel for extraction and source plasma analyses negative hydrogen ion sources at the Rutherford Appleton Laboratory

    SciTech Connect (OSTI)

    Lawrie, S. R., E-mail: scott.lawrie@stfc.ac.uk [STFC ISIS Pulsed Spallation Neutron and Muon Facility, Rutherford Appleton Laboratory, Harwell Oxford, Harwell (United Kingdom); John Adams Institute of Accelerator Science, University of Oxford, Oxford (United Kingdom); Faircloth, D. C.; Letchford, A. P.; Perkins, M.; Whitehead, M. O.; Wood, T. [STFC ISIS Pulsed Spallation Neutron and Muon Facility, Rutherford Appleton Laboratory, Harwell Oxford, Harwell (United Kingdom)] [STFC ISIS Pulsed Spallation Neutron and Muon Facility, Rutherford Appleton Laboratory, Harwell Oxford, Harwell (United Kingdom); Gabor, C. [ASTeC Intense Beams Group, Rutherford Appleton Laboratory, Harwell Oxford, Harwell (United Kingdom)] [ASTeC Intense Beams Group, Rutherford Appleton Laboratory, Harwell Oxford, Harwell (United Kingdom); Back, J. [High Energy Physics Department, University of Warwick, Coventry (United Kingdom)] [High Energy Physics Department, University of Warwick, Coventry (United Kingdom)

    2014-02-15T23:59:59.000Z

    The ISIS pulsed spallation neutron and muon facility at the Rutherford Appleton Laboratory (RAL) in the UK uses a Penning surface plasma negative hydrogen ion source. Upgrade options for the ISIS accelerator system demand a higher current, lower emittance beam with longer pulse lengths from the injector. The Front End Test Stand is being constructed at RAL to meet the upgrade requirements using a modified ISIS ion source. A new 10% duty cycle 25 kV pulsed extraction power supply has been commissioned and the first meter of 3 MeV radio frequency quadrupole has been delivered. Simultaneously, a Vessel for Extraction and Source Plasma Analyses is under construction in a new laboratory at RAL. The detailed measurements of the plasma and extracted beam characteristics will allow a radical overhaul of the transport optics, potentially yielding a simpler source configuration with greater output and lifetime.

  4. The effect of boundaries on the ion acoustic beam-plasma instability in experiment and simulation

    SciTech Connect (OSTI)

    Rapson, Christopher, E-mail: chris.rapson@ipp.mpg.de [Max Planck Institute for Plasma Physics, Boltzmannstr. 2, D-85748 Garching (Germany)] [Max Planck Institute for Plasma Physics, Boltzmannstr. 2, D-85748 Garching (Germany); Grulke, Olaf [Max Planck Institute for Plasma Physics, Wendelsteinstr. 1, 17491 Greifswald (Germany)] [Max Planck Institute for Plasma Physics, Wendelsteinstr. 1, 17491 Greifswald (Germany); Matyash, Konstantin [Institut für Physik, Ernst-Moritz-Arndt Universität, Domstr. 10a, 17489 Greifswald (Germany)] [Institut für Physik, Ernst-Moritz-Arndt Universität, Domstr. 10a, 17489 Greifswald (Germany); Klinger, Thomas [Max Planck Institute for Plasma Physics, Wendelsteinstr. 1, 17491 Greifswald (Germany) [Max Planck Institute for Plasma Physics, Wendelsteinstr. 1, 17491 Greifswald (Germany); Institut für Physik, Ernst-Moritz-Arndt Universität, Domstr. 10a, 17489 Greifswald (Germany)

    2014-05-15T23:59:59.000Z

    The ion acoustic beam-plasma instability is known to excite strong solitary waves near the Earth's bow shock. Using a double plasma experiment, tightly coupled with a 1-dimensional particle-in-cell simulation, the results presented here show that this instability is critically sensitive to the experimental conditions. Boundary effects, which do not have any counterpart in space or in most simulations, unavoidably excite parasitic instabilities. Potential fluctuations from these instabilities lead to an increase of the beam temperature which reduces the growth rate such that non-linear effects leading to solitary waves are less likely to be observed. Furthermore, the increased temperature modifies the range of beam velocities for which an ion acoustic beam plasma instability is observed.

  5. Ion beams extraction and measurements of plasma parameters on a multi-frequencies microwaves large bore ECRIS with permanent magnets

    SciTech Connect (OSTI)

    Nozaki, Dai; Kiriyama, Ryutaro; Takenaka, Tomoya; Kurisu, Yosuke; Yano, Keisuke; Sato, Fuminobu; Kato, Yushi; Iida, Toshiyuki [Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka Univ., 2-1 Yamadaoka, Suita-shi, Osaka, 565-0871 (Japan)

    2012-11-06T23:59:59.000Z

    We have developed an all-permanent magnet large bore electron cyclotron resonance ion source (ECRIS) for broad ion beam processing. The cylindrically comb-shaped magnetic field configuration is adopted for efficient plasma production and good magnetic confinement. To compensate for disadvantages of fixed magnetic configuration, a traveling wave tube amplifier (TWTA) is used. In the comb-shaped ECRIS, it is difficult to achieve controlling ion beam profiles in the whole inside the chamber by using even single frequency-controllable TWTA (11-13GHz), because of large bore size with all-magnets. We have tried controlling profiles of plasma parameters and then those of extracted ion beams by launching two largely different frequencies simultaneously, i.e., multi-frequencies microwaves. Here we report ion beam profiles and corresponding plasma parameters under various experimental conditions, dependence of ion beams against extraction voltages, and influence of different electrode positions on the electron density profile.

  6. Parametic Study of the current limit within a single driver-scaletransport beam line of an induction Linac for Heavy Ion Fusion

    SciTech Connect (OSTI)

    Prost, Lionel Robert

    2007-02-14T23:59:59.000Z

    The High Current Experiment (HCX) at Lawrence Berkeley National Laboratory is part of the US program that explores heavy-ion beam as the driver option for fusion energy production in an Inertial Fusion Energy (IFE) plant. The HCX is a beam transport experiment at a scale representative of the low-energy end of an induction linear accelerator driver. The primary mission of this experiment is to investigate aperture fill factors acceptable for the transport of space-charge-dominated heavy-ion beams at high intensity (line charge density {approx}0.2 {micro}C/m) over long pulse durations (4 {micro}s) in alternating gradient focusing lattices of electrostatic or magnetic quadrupoles. This experiment is testing transport issues resulting from nonlinear space-charge effects and collective modes, beam centroid alignment and steering, envelope matching, image charges and focusing field nonlinearities, halo and, electron and gas cloud effects. We present the results for a coasting 1 MeV K{sup +} ion beam transported through ten electrostatic quadrupoles. The measurements cover two different fill factor studies (60% and 80% of the clear aperture radius) for which the transverse phase-space of the beam was characterized in detail, along with beam energy measurements and the first halo measurements. Electrostatic quadrupole transport at high beam fill factor ({approx}80%) is achieved with acceptable emittance growth and beam loss. We achieved good envelope control, and re-matching may only be needed every ten lattice periods (at 80% fill factor) in a longer lattice of similar design. We also show that understanding and controlling the time dependence of the envelope parameters is critical to achieving high fill factors, notably because of the injector and matching section dynamics.

  7. Drift Compression of an Intense Neutralized Ion Beam P. K. Roy,1

    E-Print Network [OSTI]

    Gilson, Erik

    Drift Compression of an Intense Neutralized Ion Beam P. K. Roy,1 S. S. Yu,1 E. Henestroza,1 A. Waldron,1 D. R. Welch,2 C. Thoma,2 A. B. Sefkow,3 E. P. Gilson,3 P. C. Efthimion,3 and R. C. Davidson3 1 of a velocity-tailored, intense neutralized K beam at 300 keV, 25 mA has been demonstrated. The compression

  8. Progress on shock accelerated ion beam production on ATF

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Dover, A. Dangor, Z. Najmudin, J. Schreiber The Blackett Laboratory, Imperial College London, SW7 2BW, UK P. Shkolnikov, M. Ispiriyan Stony Brook University, Stony Brook, NY, USA...

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

    SciTech Connect (OSTI)

    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)

    2012-11-27T23:59:59.000Z

    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.

  10. Beam dynamics of a double-gap acceleration cell for ion implantation with multiple atomic species

    SciTech Connect (OSTI)

    Wadlinger, E.A.; Lysenko, W.P.; Rusnak, B. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Saadatmand, K. [Eaton Corporation, Semiconductor Equipment Operation, 108 Cherry Hill Drive, Beverly, Massachusetts 01915 (United States)

    1997-02-01T23:59:59.000Z

    As a result of our work on ion implantation, we derived equations for the beam dynamics of a two-gap-resonator cavity for accelerating and bunching various ion species of varying energies with the cavity designed for one particular ion species of a given energy (the design-reference particle). A two gap structure is useful at low resonant frequencies where lumped circuit elements (inductors) can be used and the structure kept small. A single gap structure has the advantage that each gap can be independently phased to produce the desired beam dynamics behavior for various ion species and ion energies. However at low frequencies, single gap resonant structures can be large. We find that the two-gap structure, where the phase difference between gaps, for the design reference particle, is fixed at {pi} radians can give acceptable performance provided that the individual two gap cells in the entire accelerator are optimized for the ion species having the largest mass to charge ratio and having the maximum required output energy. Our equations show how to adjust the cavity phases and electric fields to obtain equivalent first-order accelerator performance for various ion species and energies. These equations allow for the effective evaluation of various accelerator concepts and can facilitate the tuning of a linac when changing energies and ion species. Extensive simulations have confirmed the efficacy of our equations. {copyright} {ital 1997 American Institute of Physics.}

  11. Sandia National Laboratories: lithium-ion-based solid electrolyte...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ion-based solid electrolyte battery Sandia Labs, Front Edge Technology, Inc., Pacific Northwest National Lab, Univ. of California-Los Angeles: Micro Power Source On March 20, 2013,...

  12. Ion Beam Radiation Effects in Monazite , X. Deschanels2

    E-Print Network [OSTI]

    Boyer, Edmond

    ions to simulate the consequences of alpha decay. This article describes the effects, Irradiation effects, Hardness, Density, XRD, Raman spectroscopy; Deposited energy PACS: 81.05.Je, 61.82-d, 61-19] actinides, but relatively few papers dealing with compounds incorporating both tri- and tetravalent elements

  13. Ion beam analysis of materials for water purification: Partitioning of

    E-Print Network [OSTI]

    Braun, Paul

    -Champaign, Urbana, IL 61801 #12;Motivation: limited microscopic understanding of transport in interfacially (solvent) but low permeability to contaminants (solute) · Steady-state transport measurements cannot4 · Freeze-dry to remove water without disturbing the ion distribution · Polysulfone is highly

  14. Modeling the interaction of high power ion or electron beams with solid target materials

    SciTech Connect (OSTI)

    Hassanein, A.M.

    1983-11-01T23:59:59.000Z

    Intense energy deposition on first wall materials and other components as a result of plasma disruptions in magnetic fusion devices are expected to cause melting and vaporization of these materials. The exact amount of vaporization losses and melt layer thickness are very important to fusion reactor design and lifetime. Experiments using ion or electron beams to simulate the disruption effects have different environments than the actual disruption conditions in fusion reactors. A model has been developed to accurately simulate the beam-target interactions so that the results from such experiments can be meaningful and useful to reactor design. This model includes a two dimensional solution of the heat conduction equation with moving boundaries. It is found that the vaporization and melting of the sample strongly depends on the characteristics of the beam spatial distribution, beam diameter, and on the power-time variation of the beam.

  15. Fiber Optic Picosecond Laser Pulse Transmission Line for Hydrogen Ion Beam Profile Measurement

    SciTech Connect (OSTI)

    Liu, Yun [ORNL; Huang, Chunning [ORNL; Aleksandrov, Alexander V [ORNL

    2013-01-01T23:59:59.000Z

    We present a fiber optic laser pulse transmission line for non-intrusive longitudinal profile measurement of the hydrogen ion (H-) beam at the front-end of the Spallation Neutron Source (SNS) accelerator. The 80.5 MHz, 2.5 ps, multi-killowatt optical pulses are delivered to the accelerator beam line through a large mode area polarization maintaining optical fiber to ensure a high measurement stability. The transmission efficiency, output laser beam quality, pulse jitter and pulse width broadening over a 100-ft fiber line are experimentally investigated. A successful measurement of the H- beam microbunch (~130 ps) profile is obtained. Our experiment is the first demonstration of particle beam profile diagnostics using fiber optic laser pulse transmission line.

  16. Production of low axial energy spread ion beams with multicusp sources

    SciTech Connect (OSTI)

    Lee, Y.H.Y. [Univ. of California, Berkeley, CA (United States)

    1998-05-01T23:59:59.000Z

    Multicusp ion sources are capable of producing ions with low axial energy spread which are necessary in applications such as: ion projection lithography (IPL) and focused ion beams for the next generation lithographic tools and nuclear science experiments such as radioactive ion beam production. The axial ion energy spread for multicusp source is approximately 6 eV which is too large for IPL and radioactive ion beam applications. The addition of a magnetic filter which consists of a pair of permanent magnets to the multicusp source reduces the energy spread considerably. The reduction is due to the improvement in the uniformity of the axial plasma potential distribution in the discharge region. Axial ion energy spread of the filament driven ion source has been measured using three different techniques. In all cases, it was found to be less than 2 eV. Energy spread of the radio frequency (RF) driven source has also been explored, and it was found to be less than 3 eV with the proper RF-shielding. A new multicusp source configuration has been designed and constructed to further reduce the energy spread. To achieve a more uniform axial plasma potential distribution, a cylindrical magnetic filter has been designed and constructed for a 2-cm-diameter source. This new source configuration, the co-axial source, is new in its kind. The energy spread in this source has been measured to be a record low of 0.6 eV. Because of the novelty of this device, some plasma parameters inside the source have been studied. Langmuir probe has been used to measure the plasma potential, the electron temperature and the density distribution.

  17. Beam extraction and high stability operation of high current electron cyclotron resonance proton ion source

    SciTech Connect (OSTI)

    Roychowdhury, P., E-mail: pradipr@barc.gov.in; Mishra, L.; Kewlani, H.; Mittal, K. C. [Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)] [Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Patil, D. S. [Laser and Plasma Technology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)] [Laser and Plasma Technology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2014-03-15T23:59:59.000Z

    A high current electron cyclotron resonance proton ion source is designed and developed for the low energy high intensity proton accelerator at Bhabha Atomic Research Centre. The plasma discharge in the ion source is stabilized by minimizing the reflected microwave power using four stub auto tuner and magnetic field. The optimization of extraction geometry is performed using PBGUNS code by varying the aperture, shape, accelerating gap, and the potential on the electrodes. While operating the source, it was found that the two layered microwave window (6 mm quartz plate and 2 mm boron nitride plate) was damaged (a fine hole was drilled) by the back-streaming electrons after continuous operation of the source for 3 h at beam current of 20–40 mA. The microwave window was then shifted from the line of sight of the back-streaming electrons and located after the water-cooled H-plane bend. In this configuration the stable operation of the high current ion source for several hours is achieved. The ion beam is extracted from the source by biasing plasma electrode, puller electrode, and ground electrode to +10 to +50 kV, ?2 to ?4 kV, and 0 kV, respectively. The total ion beam current of 30–40 mA is recorded on Faraday cup at 40 keV of beam energy at 600–1000 W of microwave power, 800–1000 G axial magnetic field and (1.2–3.9) × 10{sup ?3} mbar of neutral hydrogen gas pressure in the plasma chamber. The dependence of beam current on extraction voltage, microwave power, and gas pressure is investigated in the range of operation of the ion source.

  18. 2D electron density profile measurement in tokamak by laser-accelerated ion-beam probe

    SciTech Connect (OSTI)

    Chen, Y. H.; Yang, X. Y.; Lin, C., E-mail: linchen0812@pku.edu.cn, E-mail: cjxiao@pku.edu.cn; Wang, X. G.; Xiao, C. J., E-mail: linchen0812@pku.edu.cn, E-mail: cjxiao@pku.edu.cn [State Key Lab of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); Wang, L. [Institute of Physics, Chinese Academy of Sciences, P. O. Box 603, Beijing 100190 (China); Xu, M. [Center for Fusion Science of Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041 (China)

    2014-11-15T23:59:59.000Z

    A new concept of Heavy Ion Beam Probe (HIBP) diagnostic has been proposed, of which the key is to replace the electrostatic accelerator of traditional HIBP by a laser-driven ion accelerator. Due to the large energy spread of ions, the laser-accelerated HIBP can measure the two-dimensional (2D) electron density profile of tokamak plasma. In a preliminary simulation, a 2D density profile was reconstructed with a spatial resolution of about 2 cm, and with the error below 15% in the core region. Diagnostics of 2D density fluctuation is also discussed.

  19. Ion-beam-induced chemical disorder in GaN

    SciTech Connect (OSTI)

    Ishimaru, Manabu; Zhang, Yanwen; Weber, William J.

    2009-09-08T23:59:59.000Z

    Atomistic structures of high-energy ion irradiated GaN have been examined using transmission electron microscopy (TEM). Single crystalline GaN substrates were irradiated at cryogenic temperature with 2 MeV Au2+ ions to a fluence of 7.35x1015 Au/cm2. Cross-sectional TEM observations revealed that damaged layers consisting of amorphous and nanocrystalline phases are formed at the surface and buried depth of the as-irradiated GaN substrate. Atomic radial distribution functions of the amorphous/poly-nanocrystalline regions showed that not only heteronuclear Ga-N bonds but also homonuclear Ga-Ga bonds exist within the first coordination shell. It was found that the ratio of heteronuclear-to-homonuclear bonds, i.e., the degree of chemical disorder is different between the surface and buried damaged layers. The alternation of chemical disorder was attributed to the difference in the defect formation processes between these layers.

  20. Title of Dissertation: MASKLESS FABRICATION OF JUNCTION FIELD EFFECT TRANSISTORS VIA FOCUSED ION BEAMS

    E-Print Network [OSTI]

    Anlage, Steven

    ABSTRACT Title of Dissertation: MASKLESS FABRICATION OF JUNCTION FIELD EFFECT TRANSISTORS VIA FOCUSED ION BEAMS Anthony John De Marco, Doctor of Philosophy, 2004 Dissertation directed by: Professor Dissertation submitted to the Faculty of the Graduate School of the University of Maryland, College Park

  1. Microstructural study of ion-beam deposited giant magnetoresistive spin valves

    E-Print Network [OSTI]

    Laughlin, David E.

    Avenue South, Minneapolis, Minnesota 55435 Detailed microstructural investigation of ion beam deposited exchanged field and R/R of the spin valves. © 1997 American Institute of Physics. S0021-8979 97 32708-X that by sputter deposition.3 This may be beneficial to the integration of the spin-valve element with other head

  2. Consequences of the ion beam irradiation on the chemical durability of Thorium Phosphate Diphosphate Kinetics study.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Consequences of the ion beam irradiation on the chemical durability of Thorium Phosphate of the long-term specific immobilization of actinides, Thorium Phosphate Diphosphate (-TPD), as potential-13], and thorium-actinide phosphate-diphosphate solid solutions (-Th4-xAnx(PO4)4P2O7) with associated -TPD

  3. Separation of beam and electrons in the spallation neutron source H{sup -} ion source

    SciTech Connect (OSTI)

    Whealton, J.H.; Raridon, R.J. [Oak Ridge National Lab., TN (United States); Leung, K.N. [Lawrence Berkeley National Lab., CA (United States)

    1997-12-01T23:59:59.000Z

    The Spallation Neutron Source (SNS) requires an ion source producing an H{sup {minus}} beam with a peak current of 35mA at a 6.2 percent duty factor. For the design of this ion source, extracted electrons must be transported and dumped without adversely affecting the H{sup {minus}} beam optics. Two issues are considered: (1) electron containment transport and controlled removal; and (2) first-order H{sup {minus}} beam steering. For electron containment, various magnetic, geometric and electrode biasing configurations are analyzed. A kinetic description for the negative ions and electrons is employed with self-consistent fields obtained from a steady-state solution to Poisson`s equation. Guiding center electron trajectories are used when the gyroradius is sufficiently small. The magnetic fields used to control the transport of the electrons and the asymmetric sheath produced by the gyrating electrons steer the ion beam. Scenarios for correcting this steering by split acceleration and focusing electrodes will be considered in some detail.

  4. Focused Ion Beam Production Using a Pyroelectric Crystal and a Resistive Glass Tube

    E-Print Network [OSTI]

    Danon, Yaron

    Focused Ion Beam Production Using a Pyroelectric Crystal and a Resistive Glass Tube T. Z. Fullem, A to accelerate electrons into a metal target has led to the production of compact X-Ray generators [4], [5], [6 tungsten tip (marketed for use in a scanning electron microscope) with an apex radius of 70 nm was mounted

  5. Ion detection device and method with compressing ion-beam shutter

    DOE Patents [OSTI]

    Sperline, Roger P [Tucson, AZ; Roger P. (Tucson, AZ)

    2009-05-26T23:59:59.000Z

    An ion detection device, method and computer readable medium storing instructions for applying voltages to shutter elements of the detection device to compress ions in a volume defined by the shutter elements and to output the compressed ions to a collector. The ion detection device has a chamber having an inlet and receives ions through the inlet, a shutter provided in the chamber opposite the inlet and configured to allow or prevent the ions to pass the shutter, the shutter having first and second shutter elements, a collector provided in the chamber opposite the shutter and configured to collect ions passed through the shutter, and a processing unit electrically connected to the first and second shutter elements. The processing unit applies, during a first predetermined time interval, a first voltage to the first shutter element and a second voltage to the second shutter element, the second voltage being lower than the first voltage such that ions from the inlet enter a volume defined by the first and second shutter elements, and during a second predetermined time interval, a third voltage to the first shutter element, higher than the first voltage, and a fourth voltage to the second shutter element, the third voltage being higher than the fourth voltage such that ions that entered the volume are compressed as the ions exit the volume and new ions coming from the inlet are prevented from entering the volume. The processing unit is electrically connected to the collector and configured to detect the compressed ions based at least on a current received from the collector and produced by the ions collected by the collector.

  6. Ion-matter interactions and applications Physical Research Laboratory

    E-Print Network [OSTI]

    Bapat, Bhas

    Astrophysics Quantum Optics Quantum Information Theoretical Physics Nuclear, Atomic, Particle Physics, Non secondary electrons effects, especially with proton beams Due to the Bragg peak, increased localized damage Therapy Traditional tumor therapy Chemo Radiation (x-ray) Disadvantage Large dose required for deep

  7. Micromilling of Metal Alloys with Focused Ion Beam-Fabricated Tools

    SciTech Connect (OSTI)

    ADAMS,DAVID P.; VASILE,M.J.; BENAVIDES,GILBERT L.; CAMPBELL,ANN N.

    1999-11-05T23:59:59.000Z

    This work combines focused ion beam sputtering and ultra-precision machining as a first step in fabricating microstructure in metals and alloys. Specifically, {approx}25{micro}m diameter micro-end mills are made from cobalt M42 high-speed steel and C2 micrograin tungsten carbide tool blanks by ion beam sputtering. A 20 keV focused gallium beam defines tool cutting edges having radii of curvature < 0.1{micro}m. Micro-end mills having 2, 4 and 5 cutting edges successfully machine small trenches in 6061-T4 aluminum, brass, 4340 steel and polymethyl methacrylate. Machined trench widths are approximately equal to the tool diameters and surface roughnesses (rms) are {approx}150 nm or less. Microtools are robust and operate for more than 6 hours without fracture. Results from ultra-precision machining aluminum at feed rates as high as 50 mm/minute are included.

  8. Monte Carlo calculations of electron beam quality conversion factors for several ion chamber types

    SciTech Connect (OSTI)

    Muir, B. R., E-mail: Bryan.Muir@nrc-cnrc.gc.ca [Measurement Science and Standards, National Research Council Canada, 1200 Montreal Road, Ottawa, Ontario K1A 0R6 (Canada); Rogers, D. W. O., E-mail: drogers@physics.carleton.ca [Carleton Laboratory for Radiotherapy Physics, Physics Department, Carleton University, 1125 ColonelBy Drive, Ottawa, Ontario K1S 5B6 (Canada)

    2014-11-01T23:59:59.000Z

    Purpose: To provide a comprehensive investigation of electron beam reference dosimetry using Monte Carlo simulations of the response of 10 plane-parallel and 18 cylindrical ion chamber types. Specific emphasis is placed on the determination of the optimal shift of the chambers’ effective point of measurement (EPOM) and beam quality conversion factors. Methods: The EGSnrc system is used for calculations of the absorbed dose to gas in ion chamber models and the absorbed dose to water as a function of depth in a water phantom on which cobalt-60 and several electron beam source models are incident. The optimal EPOM shifts of the ion chambers are determined by comparing calculations of R{sub 50} converted from I{sub 50} (calculated using ion chamber simulations in phantom) to R{sub 50} calculated using simulations of the absorbed dose to water vs depth in water. Beam quality conversion factors are determined as the calculated ratio of the absorbed dose to water to the absorbed dose to air in the ion chamber at the reference depth in a cobalt-60 beam to that in electron beams. Results: For most plane-parallel chambers, the optimal EPOM shift is inside of the active cavity but different from the shift determined with water-equivalent scaling of the front window of the chamber. These optimal shifts for plane-parallel chambers also reduce the scatter of beam quality conversion factors, k{sub Q}, as a function of R{sub 50}. The optimal shift of cylindrical chambers is found to be less than the 0.5 r{sub cav} recommended by current dosimetry protocols. In most cases, the values of the optimal shift are close to 0.3 r{sub cav}. Values of k{sub ecal} are calculated and compared to those from the TG-51 protocol and differences are explained using accurate individual correction factors for a subset of ion chambers investigated. High-precision fits to beam quality conversion factors normalized to unity in a beam with R{sub 50} = 7.5 cm (k{sub Q}{sup ?}) are provided. These factors avoid the use of gradient correction factors as used in the TG-51 protocol although a chamber dependent optimal shift in the EPOM is required when using plane-parallel chambers while no shift is needed with cylindrical chambers. The sensitivity of these results to parameters used to model the ion chambers is discussed and the uncertainty related to the practical use of these results is evaluated. Conclusions: These results will prove useful as electron beam reference dosimetry protocols are being updated. The analysis of this work indicates that cylindrical ion chambers may be appropriate for use in low-energy electron beams but measurements are required to characterize their use in these beams.

  9. Self-focusing of a Gaussian electromagnetic beam in a multi-ions plasma

    SciTech Connect (OSTI)

    Misra, Shikha; Sodha, M. S. [Centre of Energy Studies, Indian Institute of Technology Delhi (IITD), New Delhi 110016 (India)] [Centre of Energy Studies, Indian Institute of Technology Delhi (IITD), New Delhi 110016 (India); Mishra, S. K. [Institute for Plasma Research (IPR), Gandhinagar 382428 (India)] [Institute for Plasma Research (IPR), Gandhinagar 382428 (India)

    2013-10-15T23:59:59.000Z

    In this paper, the authors have developed a formulation for the dependence of electron and ion densities on the irradiance of an electromagnetic beam in a plasma with multiply charged ions, corresponding to collisional, ponderomotive, and relativistic-ponderomotive nonlinearities and different electron/ion temperatures; consequently, the corresponding expressions for the electron density modification in the presence of an electromagnetic (em) field have been derived. Paraxial approach in the vicinity of intensity maximum has been adopted to analyze the propagation characteristics of an em beam in such plasmas; on the basis of this analysis, critical curves and self-focusing curves have been computed numerically and graphically illustrated. For a numerical appreciation of the analysis, we have specifically carried out the computations for the simultaneous presence of singly and doubly charged ions in the plasma. As an important outcome, it is seen that the nonlinear effects (and hence self-focusing) get suppressed in the presence of multiply ionized ions; the conditions for the three modes of em-beam propagation viz. oscillatory focusing/defocusing and steady divergence have been discussed.

  10. Epitaxial GaN films by hyperthermal ion-beam nitridation of Ga droplets

    SciTech Connect (OSTI)

    Gerlach, J. W.; Ivanov, T.; Neumann, L.; Hoeche, Th.; Hirsch, D.; Rauschenbach, B. [Leibniz-Institut fuer Oberflaechenmodifizierung (IOM), D-04318 Leipzig (Germany)

    2012-06-01T23:59:59.000Z

    Epitaxial GaN film formation on bare 6H-SiC(0001) substrates via the process of transformation of Ga droplets into a thin GaN film by applying hyperthermal nitrogen ions is investigated. Pre-deposited Ga atoms in well defined amounts form large droplets on the substrate surface which are subsequently nitridated at a substrate temperature of 630 Degree-Sign C by a low-energy nitrogen ion beam from a constricted glow-discharge ion source. The Ga deposition and ion-beam nitridation process steps are monitored in situ by reflection high-energy electron diffraction. Ex situ characterization by x-ray diffraction and reflectivity techniques, Rutherford backscattering spectrometry, and electron microscopy shows that the thickness of the resulting GaN films depends on the various amounts of pre-deposited gallium. The films are epitaxial to the substrate, exhibit a mosaic like, smooth surface topography and consist of coalesced large domains of low defect density. Possible transport mechanisms of reactive nitrogen species during hyperthermal nitridation are discussed and the formation of GaN films by an ion-beam assisted process is explained.

  11. Simulation of direct plasma injection for laser ion beam acceleration with a radio frequency quadrupole

    SciTech Connect (OSTI)

    Jin, Q. Y.; Li, Zh. M.; Liu, W. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); School of Physics, University of Chinese Academy of Sciences, Beijing 100049 (China); Zhao, H. Y., E-mail: zhaohy@impcas.ac.cn; Zhang, J. J.; Sha, Sh.; Zhang, Zh. L.; Zhang, X. Zh.; Sun, L. T.; Zhao, H. W. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China)

    2014-07-15T23:59:59.000Z

    The direct plasma injection scheme (DPIS) has been being studied at Institute of Modern Physics since several years ago. A C{sup 6+} beam with peak current of 13 mA, energy of 593 keV/u has been successfully achieved after acceleration with DPIS method. To understand the process of DPIS, some simulations have been done as follows. First, with the total current intensity and the relative yields of different charge states for carbon ions measured at the different distance from the target, the absolute current intensities and time-dependences for different charge states are scaled to the exit of the laser ion source in the DPIS. Then with these derived values as the input parameters, the extraction of carbon beam from the laser ion source to the radio frequency quadrupole with DPIS is simulated, which is well agreed with the experiment results.

  12. Resolution Improvement and Pattern Generator Development for theMaskless Micro-Ion-Beam Reduction Lithography System

    SciTech Connect (OSTI)

    Jiang, Ximan

    2006-05-18T23:59:59.000Z

    The shrinking of IC devices has followed the Moore's Law for over three decades, which states that the density of transistors on integrated circuits will double about every two years. This great achievement is obtained via continuous advance in lithography technology. With the adoption of complicated resolution enhancement technologies, such as the phase shifting mask (PSM), the optical proximity correction (OPC), optical lithography with wavelength of 193 nm has enabled 45 nm printing by immersion method. However, this achievement comes together with the skyrocketing cost of masks, which makes the production of low volume application-specific IC (ASIC) impractical. In order to provide an economical lithography approach for low to medium volume advanced IC fabrication, a maskless ion beam lithography method, called Maskless Micro-ion-beam Reduction Lithography (MMRL), has been developed in the Lawrence Berkeley National Laboratory. The development of the prototype MMRL system has been described by Dr. Vinh Van Ngo in his Ph.D. thesis. But the resolution realized on the prototype MMRL system was far from the design expectation. In order to improve the resolution of the MMRL system, the ion optical system has been investigated. By integrating a field-free limiting aperture into the optical column, reducing the electromagnetic interference and cleaning the RF plasma, the resolution has been improved to around 50 nm. Computational analysis indicates that the MMRL system can be operated with an exposure field size of 0.25 mm and a beam half angle of 1.0 mrad on the wafer plane. Ion-ion interactions have been studied with a two-particle physics model. The results are in excellent agreement with those published by the other research groups. The charge-interaction analysis of MMRL shows that the ion-ion interactions must be reduced in order to obtain a throughput higher than 10 wafers per hour on 300-mm wafers. In addition, two different maskless lithography strategies have been studied. The dependence of the throughput with the exposure field size and the speed of the mechanical stage has been investigated. In order to perform maskless lithography, different micro-fabricated pattern generators have been developed for the MMRL system. Ion beamlet switching has been successfully demonstrated on the MMRL system. A positive bias voltage around 10 volts is sufficient to switch off the ion current on the micro-fabricated pattern generators. Some unexpected problems, such as the high-energy secondary electron radiations, have been discovered during the experimental investigation. Thermal and structural analysis indicates that the aperture displacement error induced by thermal expansion can satisfy the 3{delta} CD requirement for lithography nodes down to 25 nm. The cross-talking effect near the surface and inside the apertures of the pattern generator has been simulated in a 3-D ray-tracing code. New pattern generator design has been proposed to reduce the cross-talking effect. In order to eliminate the surface charging effect caused by the secondary electrons, a new beam-switching scheme in which the switching electrodes are immersed in the plasma has been demonstrated on a mechanically fabricated pattern generator.

  13. Integration of a broad beam ion source with a high-temperature x-ray diffraction vacuum chamber

    SciTech Connect (OSTI)

    Manova, D.; Bergmann, A.; Maendl, S.; Neumann, H.; Rauschenbach, B. [Leibniz-Institut fuer Oberflaechenmodifizierung e. V., Permoserstr. 15, 04318 Leipzig (Germany)

    2012-11-15T23:59:59.000Z

    Here, the integration of a low energy, linearly variable ion beam current density, mechanically in situ adjustable broad beam ion source with a high-temperature x-ray diffraction (XRD) vacuum chamber is reported. This allows in situ XRD investigation of phase formation and evolution processes induced by low energy ion implantation. Special care has been taken to an independent adjustment of the ion beam for geometrical directing towards the substrate, a 15 mm small ion source exit aperture to avoid a secondary sputter process of the chamber walls, linearly variable ion current density by using a pulse length modulation (PLM) for the accelerating voltages without changing the ion beam density profile, nearly homogeneous ion beam distribution over the x-ray footprint, together with easily replaceable Kapton{sup Registered-Sign} windows for x-rays entry and exit. By combining a position sensitive x-ray detector with this PLM-modulated ion beam, a fast and efficient time resolved investigation of low energy implantation processes is obtained in a compact experimental setup.

  14. The Heavy Ion Fusion Virtual National Laboratory Overview of U.S. Heavy Ion Fusion Research*

    E-Print Network [OSTI]

    -76SF00098 and W-7405-Eng-48, and by the Princeton Plasma Physics Laboratory under Contract Number DE

  15. Contribution of ion beam analysis methods to the development of 2nd generation high temperature superconducting (HTS) wires

    SciTech Connect (OSTI)

    Usov, Igor O [Los Alamos National Laboratory; Arendt, Paul N [Los Alamos National Laboratory; Stan, Liliana [Los Alamos National Laboratory; Holesinger, Terry G [Los Alamos National Laboratory; Foltyn, Steven R [Los Alamos National Laboratory; Depaula, Raymond F [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    One of the crucial steps in the second generation high temperature superconducting wire program was development of the buffer layer architecture. The architecture designed at the Superconductivity Technology Center at Los Alamos National Laboratory consists of several oxide layers wherein each layer plays a specific role, namely: nucleation layer, diffusion barrier, biaxially textured template, and an intermediate layer with a good match to the lattice parameter of superconducting Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7} (YBCO) compound. This report demonstrates how a wide range of ion beam analysis techniques (SIMS, RBS, channeling, PIXE, PIGE, NRA, ERD) was employed for analysis of each buffer layer and the YBCO films. These results assisted in understanding of a variety of physical processes occurring during the buffet layer fabrication and helped to optimize the buffer layer architecture as a whole.

  16. Heavy Ion Beam in Resolution of the Critical Point Problem for Uranium and Uranium Dioxide

    E-Print Network [OSTI]

    Igor Iosilevskiy; Victor Gryaznov

    2010-05-23T23:59:59.000Z

    Important advantages of heavy ion beam (HIB) irradiation of matter are discussed in comparison with traditional sources - laser heating, electron beam, electrical discharge etc. High penetration length (~ 10 mm) is of primary importance for investigation of dense matter properties. This gives an extraordinary chance to reach the uniform heating regime when HIB irradiation is being used for thermophysical property measurements. Advantages of HIB heating of highly-dispersive samples are claimed for providing free and relatively slow quasi-isobaric heating without fast hydrodynamic expansion of heated sample. Perspective of such HIB application are revised for resolution of long-time thermophysical problems for uranium and uranium-bearing compounds (UO2). The priorities in such HIB development are stressed: preferable energy levels, beam-time duration, beam focusing, deposition of the sample etc.

  17. Collinear Laser-Beam Ion-Beam Measurement of the Mean Lifetime of the Ar Ii 4p'2f-Degrees-7/2 Level

    E-Print Network [OSTI]

    Jin, J.; Church, David A.

    1993-01-01T23:59:59.000Z

    The mean lifetime tau of the 4p'F-2(7/2)-degrees level of Ar II has been measured using a variant of the collinear laser-beam-fast-ion-beam spectroscopy technique. Our variant requires no mechanical motion or laser frequency tuning. The result...

  18. Temperature dependence of ion-beam mixing in crystalline and amorphous germanium isotope multilayer structures

    SciTech Connect (OSTI)

    Radek, M.; Bracht, H., E-mail: bracht@uni-muenster.de [Institute of Materials Physics, Westfälische Wilhelms-Universität Münster, 48149 Münster (Germany); Posselt, M.; Liedke, B.; Schmidt, B. [Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraße 400, D-01328 Dresden (Germany); Bougeard, D. [Institut für Experimentelle und Angewandte Physik, 93040 Regensburg (Germany)

    2014-01-14T23:59:59.000Z

    Self-atom mixing induced by 310 keV gallium (Ga) ion implantation in crystalline and preamorphized germanium (Ge) at temperatures between 164 K and 623 K and a dose of 1?×?10{sup 15}?cm{sup ?2} is investigated using isotopic multilayer structures of alternating {sup 70}Ge and {sup nat}Ge layers grown by molecular beam epitaxy. The distribution of the implanted Ga atoms and the ion-beam induced depth-dependent self-atom mixing was determined by means of secondary ion mass spectrometry. Three different temperature regimes of self-atom mixing, i.e., low-, intermediate-, and high-temperature regimes are observed. At temperatures up to 423 K, the mixing is independent of the initial structure, whereas at 523?K, the intermixing of the preamorphized Ge structure is about twice as high as that of crystalline Ge. At 623?K, the intermixing of the initially amorphous Ge structure is strongly reduced and approaches the mixing of the crystalline material. The temperature dependence of ion-beam mixing is described by competitive amorphization and recrystallization processes.

  19. Emission Spectroscopy of Highly Charged Ions in Plasma of an Electron Beam Ion Trap

    SciTech Connect (OSTI)

    Draganic, I. [Vinca Institute of Nuclear Sciences, P.O. Box 522, 11001 Belgrade (Serbia and Montenegro); Max-Planck Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Crespo Lopez-Urrutia, J.R.; Soria Orts, R.; Ullrich, J. [Max-Planck Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); DuBois, R. [University of Missouri-Rolla, Physics Building, Rolla, MO 63409-0640 (United States); Shevelko, V. [Lebedev Physical Institute, Russian Academy of Science, 117924 Moscow (Russian Federation); Fritzsche, S. [Department of Physics, University of Kassel, Heinrich-Plett-St. 40, D-34132 Kassel (Germany); Zou, Y. [Applied Ion Beam Physics Lab, Fudan University, Shanghai 200433 (China)

    2004-12-01T23:59:59.000Z

    The results of experimental study of magnetic dipole (M1) transitions in highly charged ions of argon (Ar9+, Ar10+, Ar13+ and Ar14+) and krypton (Kr18+ and Kr22+) are presented. The forbidden transitions of the highly charged ions in the visible and near UV range of the photon emission spectra have been measured with accuracy better than 1 ppm. Our measurements for the 'coronal lines' are the most accurate yet reported using an EBIT as a spectroscopic source of highly charged ions. These precise wavelength determinations provide a useful test and challenge for atomic structure calculations of many-electron systems.

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

    SciTech Connect (OSTI)

    Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Marusic, A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2014-09-09T23:59:59.000Z

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

  1. Extraction of highly charged ions from the electron beam ion trap at LBNL for applications in surface analysis and Materials Science

    E-Print Network [OSTI]

    2001-01-01T23:59:59.000Z

    Electron Beam Ion Trap at LBNL for Applications in Surfacetransferred from LLNL to LBNL, and is now operating with+ . The research program at LBNL is focused on the following

  2. Investigation into direct conversion with medium energy He-ion beams

    E-Print Network [OSTI]

    Guild-Bingham, Avery A.

    2005-02-17T23:59:59.000Z

    efficiency was found using a He+ ion beam to be approximately 88% for beam energies ranging from 20 to 80 keV. The 2.4 1012 ? 10% ohm resistor used in the experiment holds-up under the stress of high voltage to 40 kV. Electric current leakage tests... to be confirmed before it is conclusive that the resistor is sufficient for the FFMCR prototype. The leakage tests also indicate that Teflon? is quite sufficient as an insulator for potentials as high as 40 kV. It was apparent that the surface of the Teflon...

  3. Monte Carlo calculations for reference dosimetry of electron beams with the PTW Roos and NE2571 ion chambers

    SciTech Connect (OSTI)

    Muir, B. R., E-mail: bmuir@physics.carleton.ca; Rogers, D. W. O., E-mail: drogers@physics.carleton.ca [Physics Department, Carleton Laboratory for Radiotherapy Physics, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada)] [Physics Department, Carleton Laboratory for Radiotherapy Physics, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada)

    2013-12-15T23:59:59.000Z

    Purpose: To investigate recommendations for reference dosimetry of electron beams and gradient effects for the NE2571 chamber and to provide beam quality conversion factors using Monte Carlo simulations of the PTW Roos and NE2571 ion chambers. Methods: The EGSnrc code system is used to calculate the absorbed dose-to-water and the dose to the gas in fully modeled ion chambers as a function of depth in water. Electron beams are modeled using realistic accelerator simulations as well as beams modeled as collimated point sources from realistic electron beam spectra or monoenergetic electrons. Beam quality conversion factors are calculated with ratios of the doses to water and to the air in the ion chamber in electron beams and a cobalt-60 reference field. The overall ion chamber correction factor is studied using calculations of water-to-air stopping power ratios. Results: The use of an effective point of measurement shift of 1.55 mm from the front face of the PTW Roos chamber, which places the point of measurement inside the chamber cavity, minimizes the difference betweenR{sub 50}, the beam quality specifier, calculated from chamber simulations compared to that obtained using depth-dose calculations in water. A similar shift minimizes the variation of the overall ion chamber correction factor with depth to the practical range and reduces the root-mean-square deviation of a fit to calculated beam quality conversion factors at the reference depth as a function of R{sub 50}. Similarly, an upstream shift of 0.34 r{sub cav} allows a more accurate determination of R{sub 50} from NE2571 chamber calculations and reduces the variation of the overall ion chamber correction factor with depth. The determination of the gradient correction using a shift of 0.22 r{sub cav} optimizes the root-mean-square deviation of a fit to calculated beam quality conversion factors if all beams investigated are considered. However, if only clinical beams are considered, a good fit to results for beam quality conversion factors is obtained without explicitly correcting for gradient effects. The inadequacy of R{sub 50} to uniquely specify beam quality for the accurate selection of k{sub Q} factors is discussed. Systematic uncertainties in beam quality conversion factors are analyzed for the NE2571 chamber and amount to between 0.4% and 1.2% depending on assumptions used. Conclusions: The calculated beam quality conversion factors for the PTW Roos chamber obtained here are in good agreement with literature data. These results characterize the use of an NE2571 ion chamber for reference dosimetry of electron beams even in low-energy beams.

  4. Z-petawatt driven ion beam radiography development.

    SciTech Connect (OSTI)

    Schollmeier, Marius; Geissel, Matthias; Rambo, Patrick K.; Schwarz, Jens; Sefkow, Adam B.

    2013-09-01T23:59:59.000Z

    Laser-driven proton radiography provides electromagnetic field mapping with high spatiotemporal resolution, and has been applied to many laser-driven High Energy Density Physics (HEDP) experiments. Our report addresses key questions about the feasibility of ion radiography at the Z-Accelerator (%E2%80%9CZ%E2%80%9D), concerning laser configuration, hardware, and radiation background. Charged particle tracking revealed that radiography at Z requires GeV scale protons, which is out of reach for existing and near-future laser systems. However, it might be possible to perform proton deflectometry to detect magnetic flux compression in the fringe field region of a magnetized liner inertial fusion experiment. Experiments with the Z-Petawatt laser to enhance proton yield and energy showed an unexpected scaling with target thickness. Full-scale, 3D radiation-hydrodynamics simulations, coupled to fully explicit and kinetic 2D particle-in-cell simulations running for over 10 ps, explain the scaling by a complex interplay of laser prepulse, preplasma, and ps-scale temporal rising edge of the laser.

  5. Percolation of gallium dominates the electrical resistance of focused ion beam deposited metals

    SciTech Connect (OSTI)

    Faraby, H. [Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, California 92093 (United States); DiBattista, M. [Qualcomm Technologies Incorporated, San Diego, California 92121 (United States); Bandaru, P. R., E-mail: pbandaru@ucsd.edu [Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, California 92093 (United States)

    2014-04-28T23:59:59.000Z

    Metal deposition through focused ion beam (FIB) based systems is thought to result in material composed of the primary metal from the metallo-organic precursor in addition to carbon, oxygen, and gallium. We determined, through electrical resistance and chemical composition measurements on a wide range of FIB deposited platinum and tungsten lines, that the gallium ion (Ga{sup +}) concentration in the metal lines plays the dominant role in controlling the electrical resistivity. Effective medium theory, based on McLachlan's formalisms, was used to describe the relationship between the Ga{sup +} concentration and the corresponding resistivity.

  6. The beam energy dependence of collective flow in heavy ion collisions

    E-Print Network [OSTI]

    Petersen, Hannah; Auvinen, Jussi; Bleicher, Marcus

    2015-01-01T23:59:59.000Z

    The major goals of heavy ion research are to explore the phase diagram of quantum chromodynamics (QCD) and to investigate the properties of the quark gluon plasma (QGP), a new state of matter created at high temperatures and/or densities. Collective anisotropic flow is one of the most promising observables to gain insights about the properties of the system created in relativistic heavy ion reactions. The current status of the beam energy dependence of the first three Fourier coefficients of the azimuthal distribution of the produced particles $v_1$ to $v_3$ within hybrid transport plus hydrodynamics approaches are summarized.

  7. The beam energy dependence of collective flow in heavy ion collisions

    E-Print Network [OSTI]

    Hannah Petersen; Jan Steinheimer; Jussi Auvinen; Marcus Bleicher

    2015-03-11T23:59:59.000Z

    The major goals of heavy ion research are to explore the phase diagram of quantum chromodynamics (QCD) and to investigate the properties of the quark gluon plasma (QGP), a new state of matter created at high temperatures and/or densities. Collective anisotropic flow is one of the most promising observables to gain insights about the properties of the system created in relativistic heavy ion reactions. The current status of the beam energy dependence of the first three Fourier coefficients of the azimuthal distribution of the produced particles $v_1$ to $v_3$ within hybrid transport plus hydrodynamics approaches are summarized.

  8. The Heavy Ion Fusion Science Virtual National Laboratory Collective effects of intense ion

    E-Print Network [OSTI]

    , Tajima and Dawson, PRL 43, 267 (1979). Beam -plasma wake field accelerator P. Chen et al, PRL 54, 693. Robertson, PRL, 48, 149 (1982). Thin collective lens R. Kraft, Phys. Fluids, 30, 245 (1987). Thick

  9. Radiobiologic Significance of Response of Intratumor Quiescent Cells In Vivo to Accelerated Carbon Ion Beams Compared With {gamma}-Rays and Reactor Neutron Beams

    SciTech Connect (OSTI)

    Masunaga, Shin-ichiro [Particle Radiation Oncology Research Center, Research Reactor Institute, Kyoto University, Kumatori, Osaka (Japan)], E-mail: smasuna@rri.kyoto-u.ac.jp; Ando, Koichi; Uzawa, Akiko; Hirayama, Ryoichi; Furusawa, Yoshiya; Koike, Sachiko [Heavy-Ion Radiobiology Research Group, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan); Sakurai, Yoshinori [Department of Physics, Faculty of Medicine, Sapporo Medical University, Sapporo (Japan); Nagata, Kenji; Suzuki, Minoru; Kashino, Genro [Particle Radiation Oncology Research Center, Research Reactor Institute, Kyoto University, Kumatori, Osaka (Japan); Kinashi, Yuko [Department of Radiation Safety and Control, Research Reactor Institute, Kyoto University, Kumatori, Osaka (Japan); Tanaka, Hiroki; Maruhashi, Akira [Department of Radiation Medical Physics, Research Reactor Institute, Kyoto University, Kumatori, Osaka (Japan); Ono, Koji [Particle Radiation Oncology Research Center, Research Reactor Institute, Kyoto University, Kumatori, Osaka (Japan)

    2008-01-01T23:59:59.000Z

    Purpose: To clarify the radiosensitivity of intratumor quiescent cells in vivo to accelerated carbon ion beams and reactor neutron beams. Methods and Materials: Squamous cell carcinoma VII tumor-bearing mice were continuously given 5-bromo-2'-deoxyuridine to label all intratumor proliferating cells. Next, they received accelerated carbon ion or {gamma}-ray high-dose-rate (HDR) or reduced-dose-rate (RDR) irradiation. Other tumor-bearing mice received reactor thermal or epithermal neutrons with RDR irradiation. Immediately after HDR and RDR irradiation or 12 h after HDR irradiation, the response of quiescent cells was assessed in terms of the micronucleus frequency using immunofluorescence staining for 5-bromo-2'-deoxyuridine. The response of the total (proliferating plus quiescent) tumor cells was determined from the 5-bromo-2'-deoxyuridine nontreated tumors. Results: The difference in radiosensitivity between the total and quiescent cell populations after {gamma}-ray irradiation was markedly reduced with reactor neutron beams or accelerated carbon ion beams, especially with a greater linear energy transfer (LET) value. Clearer repair in quiescent cells than in total cells through delayed assay or a decrease in the dose rate with {gamma}-ray irradiation was efficiently inhibited with carbon ion beams, especially with a greater LET. With RDR irradiation, the radiosensitivity to accelerated carbon ion beams with a greater LET was almost similar to that to reactor thermal and epithermal neutron beams. Conclusion: In terms of tumor cell-killing effect as a whole, including quiescent cells, accelerated carbon ion beams, especially with greater LET values, are very useful for suppressing the dependency on the heterogeneity within solid tumors, as well as depositing the radiation dose precisely.

  10. Planarization of amorphous carbon films on patterned substrates using gas cluster ion beams

    SciTech Connect (OSTI)

    Toyoda, Noriaki; Yamada, Isao [Incubation Center, University of Hyogo, 2167 Shosha, Himeji, Hyogo 671-2280 (Japan); Nagato, Keisuke; Nakao, Masayuki; Hamaguchi, Tetsuya [Department of Engineering Synthesis, School of Engineering, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Tani, Hiroshi [Department of Mechanical Engineering, Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680 (Japan); Sakane, Yasuo [Western Digital Media Operations, 1710 Automation Parkway, San Jose, CA 95131 (United States)

    2009-04-01T23:59:59.000Z

    Surface planarization and modification of a patterned surface were demonstrated using gas cluster ion beam (GCIB). Grooves with 100-400 nm intervals were formed on amorphous carbon films using focused ion beams to study the special frequency dependence of the planarization. Also, line and space patterns were fabricated on Si substrates, and amorphous carbons were deposited as a model structure of discrete track media. Subsequently, surface planarization using Ar-GCIB was carried out. After GCIB irradiations, all of the grooves were completely removed, and a flat surface was realized. And it showed that GCIB irradiation planarized grooves without huge thickness loss. From the power spectrum density of an atomic force microscope, GCIB preferentially removed grooves with small intervals. It was found from energy dispersive x-ray spectroscopy that surface planarization without severe damage in the amorphous carbon and magnetic layers was carried out with GCIB.

  11. Harmonic analysis of irradiation asymmetry for cylindrical implosions driven by high-frequency rotating ion beams

    E-Print Network [OSTI]

    Bret, Antoine; Tahir, Naeem

    2012-01-01T23:59:59.000Z

    Cylindrical implosions driven by intense heavy ions beams should be instrumental in a near future to study High Energy Density Matter. By rotating the beam by means of a high frequency wobbler, it should be possible to deposit energy in the outer layers of a cylinder, compressing the material deposited in its core. The beam temporal profile should however generate an inevitable irradiation asymmetry likely to feed the Rayleigh-Taylor instability (RTI) during the implosion phase. In this paper, we compute the Fourier components of the target irradiation in order to make the junction with previous works on RTI performed in this setting. Implementing a 1D and 2D beam models, we find these components can be expressed exactly in terms of the Fourier transform of the temporal beam profile. If $T$ is the beam duration and $\\Omega$ its rotation frequency, "magic products" $\\Omega T$ can be identified which cancel the first harmonic of the deposited density, resulting in an improved irradiation symmetry.

  12. Note: Production of a mercury beam with an electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Vondrasek, R.; Pardo, R.; Scott, R. [Physics Division, Argonne National Laboratory, Lemont, Illinois 60439 (United States)] [Physics Division, Argonne National Laboratory, Lemont, Illinois 60439 (United States)

    2013-11-15T23:59:59.000Z

    An electron cyclotron resonance ion source has been utilized to produce mercury beams with intensities of 4.5 e?A of {sup 202}Hg{sup 29+} and 3.0 e?A of {sup 202}Hg{sup 31+} from natural abundance mercury metal. The production technique relies on the evaporation of liquid mercury into the source plasma vacuum region and utilizes elemental mercury instead of a volatile organic compound as the neutral feed material.

  13. Simulations and experiments of intense ion beam current density compression in space and timea...

    E-Print Network [OSTI]

    Kaganovich, Igor

    . Leitner,3 S. M. Lidia,3 P. K. Roy,3 P. A. Seidl,3 W. L. Waldron,3 S. S. Yu,3 and D. R. Welch4 1 Sandia longitudinal pulse compression of ion beams on the Neutralized Drift Compression Experiment NDCX P. K. Roy et. B. Sefkow,1,b R. C. Davidson,2 E. P. Gilson,3 I. D. Kaganovich,2 A. Anders,3 J. E. Coleman,3 M

  14. Beta Beams for neutrino production: Heat deposition from decaying ions in superconducting magnets

    E-Print Network [OSTI]

    Wildner, Elena; Cerutti, Francesco

    This note describes studies of energy deposition in superconducting magnets from secondary ions in the “beta beam” decay ring as described in the base-line scenario of the EURISOL Beta Beam Design Study. The lattice structure proposed in the Design Study has absorber elements inserted between the superconducting magnets to protect the magnet coils. We describe an efficient and small model made to carry out the study. The specially developed options in the beam code “ACCSIM” to track largely off-momentum particles has permitted to extract the necessary information to interface the transport and interaction code “FLUKA” with the aim to calculate the heat deposition in the magnets and the absorbers. The two beta emitters 18Ne10+ and 6He2+ used for neutrino and anti-neutrino production and their daughter ions have been tracked. The absorber system proposed in the Design Study is efficient to intercept the ions decayed in the arc straight sections as foreseen, however, the continuous decay in the dipol...

  15. Beta Beams for Neutrino Production Heat Deposition from Decaying Ions in Superconducting Magnets

    E-Print Network [OSTI]

    Wildner, Elena; Cerutti, F

    2008-01-01T23:59:59.000Z

    This report describes studies of energy deposition in superconducting magnets from secondary ions in the "beta beam" decay ring as described in the base-line scenario of the EURISOL Beta Beam Design Study. The lattice structure proposed in the Design Study has absorber elements inserted between the superconducting magnets to protect the magnet coils. We describe an efficient and small model made to carry out the study. The specially developed options in the beam code "ACCSIM" to track largely off-momentum particles has permitted to extract the necessary information to interface the transport and interaction code "FLUKA" with the aim to calculate the heat deposition in the magnets and the absorbers. The two beta emitters 18Ne10+ and 6He2+ used for neutrino and anti-neutrino production and their daughter ions have been tracked. The absorber system proposed in the Design Study is efficient to intercept the ions decayed in the arc straight sections as foreseen, however, the continuous decay in the dipoles induce ...

  16. Toroidal ripple transport of beam ions in the mega-ampere spherical tokamak

    SciTech Connect (OSTI)

    McClements, K. G. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Hole, M. J. [Plasma Research Laboratory, Research School of Physical Science and Engineering, Australian National University, Canberra, ACT 0200 (Australia)

    2012-07-15T23:59:59.000Z

    The transport of injected beam ions due to toroidal magnetic field ripple in the mega-ampere spherical tokamak (MAST) is quantified using a full orbit particle tracking code, with collisional slowing-down and pitch-angle scattering by electrons and bulk ions taken into account. It is shown that the level of ripple losses is generally rather low, although it depends sensitively on the major radius of the outer midplane plasma edge; for typical values of this parameter in MAST plasmas, the reduction in beam heating power due specifically to ripple transport is less than 1%, and the ripple contribution to beam ion diffusivity is of the order of 0.1 m{sup 2} s{sup -1} or less. It is concluded that ripple effects make only a small contribution to anomalous transport rates that have been invoked to account for measured neutron rates and plasma stored energies in some MAST discharges. Delayed (non-prompt) losses are shown to occur close to the outer midplane, suggesting that banana-drift diffusion is the most likely cause of the ripple-induced losses.

  17. Subcellular Spatial Correlation of Particle Traversal and Biological Response in Clinical Ion Beams

    SciTech Connect (OSTI)

    Niklas, Martin, E-mail: m.niklas@dkfz.de [Division of Medical Physics in Radiation Oncology, German Cancer Research Center, Heidelberg (Germany); German Cancer Consortium, National Center for Radiation Research in Oncology, Heidelberg Institute of Radiation Oncology, Heidelberg (Germany); Abdollahi, Amir [German Cancer Consortium, National Center for Radiation Research in Oncology, Heidelberg Institute of Radiation Oncology, Heidelberg (Germany); Molecular and Translational Radiation Oncology, Heidelberg Ion-Beam Therapy Center, University of Heidelberg Medical School and National Center for Tumor Diseases, German Cancer Research Center, Heidelberg (Germany); Department of Radiation Oncology and Radiation Therapy, University Hospital Heidelberg, Heidelberg (Germany); Heidelberg Ion-Beam Therapy Center, Heidelberg (Germany); Akselrod, Mark S. [Stillwater Crystal Growth Division, Landauer Inc, Stillwater, Oklahoma (United States); Debus, Jürgen [German Cancer Consortium, National Center for Radiation Research in Oncology, Heidelberg Institute of Radiation Oncology, Heidelberg (Germany); Molecular and Translational Radiation Oncology, Heidelberg Ion-Beam Therapy Center, University of Heidelberg Medical School and National Center for Tumor Diseases, German Cancer Research Center, Heidelberg (Germany); Department of Radiation Oncology and Radiation Therapy, University Hospital Heidelberg, Heidelberg (Germany); Heidelberg Ion-Beam Therapy Center, Heidelberg (Germany); Jäkel, Oliver [Division of Medical Physics in Radiation Oncology, German Cancer Research Center, Heidelberg (Germany); German Cancer Consortium, National Center for Radiation Research in Oncology, Heidelberg Institute of Radiation Oncology, Heidelberg (Germany); Department of Radiation Oncology and Radiation Therapy, University Hospital Heidelberg, Heidelberg (Germany); Heidelberg Ion-Beam Therapy Center, Heidelberg (Germany); and others

    2013-12-01T23:59:59.000Z

    Purpose: To report on the spatial correlation of physical track information (fluorescent nuclear track detectors, FNTDs) and cellular DNA damage response by using a novel hybrid detector (Cell-Fit-HD). Methods and Materials: The FNTDs were coated with a monolayer of human non-small cell lung carcinoma (A549) cells and irradiated with carbon ions (270.55 MeV u{sup ?1}, rising flank of the Bragg peak). Phosphorylated histone variant H2AX accumulating at the irradiation-induced double-strand break site was labeled (RIF). The position and direction of ion tracks in the FNTD were registered with the location of the RIF sequence as an ion track surrogate in the cell layer. Results: All RIF sequences could be related to their corresponding ion tracks, with mean deviations of 1.09 ?m and ?1.72 ?m in position and of 2.38° in slope. The mean perpendicular between ion track and RIF sequence was 1.58 ?m. The mean spacing of neighboring RIFs exhibited a regular rather than random spacing. Conclusions: Cell-Fit-HD allows for unambiguous spatial correlation studies of cell damage with respect to the intracellular ion traversal under therapeutic beam conditions.

  18. Ion-Beam-Induced Chemical Mixing at a Nanocrystalline CeO2–Si Interface

    SciTech Connect (OSTI)

    Edmondson, P. D.; Young, Niel P.; Parish, Chad M.; Moll, Sandra J.; Namavar, Fereydoon; Weber, William J.; Zhang, Yanwen

    2013-02-28T23:59:59.000Z

    Thin films of nanocrystalline ceria deposited onto a silicon substrate have been irradiated with 3 MeV Au+ ions to a total dose of 34 displacements per atom to examine the film/substrate interfacial response upon displacement damage. Under irradiation, a band of contrast is observed to form that grows under further irradiation. Scanning and high-resolution transmission electron microscopy imaging and analysis suggest that this band of contrast is a cerium silicate phase with an approximate Ce:Si:O composition ratio of 1:1:3 in an amorphous nature. The slightly nonstoichiometric composition arises due to the loss of mobile oxygen within the cerium silicate phase under the current irradiation condition. This nonequilibrium phase is formed as a direct result of ion-beam-induced chemical mixing caused by ballistic collisions between the incoming ion and the lattice atoms. This may hold promise in ion beam engineering of cerium silicates for microelectronic applications e.g., the fabrication of blue LEDs.

  19. Ion-Beam-Induced Chemical Mixing at a Nanocrystalline CeO2 Si Interface

    SciTech Connect (OSTI)

    Edmondson, Dr. Philip [University of Oxford; Young, Neil P. [Department of Materials, University of Oxford, Parks Rd, Oxford, OX1 3PH, UK; Parish, Chad M [ORNL; Moll, Sandra [CEA, Saclay, France; Namavar, Fereydoon [University of Nebraska Medical Center; Weber, William J [ORNL; Zhang, Yanwen [ORNL

    2013-01-01T23:59:59.000Z

    Thin films of nanocrystalline ceria deposited onto a silicon substrate have been irradiated with 3 MeV Au+ ions to a total dose of 34 displacements per atom to examine the film/substrate interfacial response upon displacement damage. Under irradiation, a band of contrast is observed to form that grows under further irradiation. Scanning and high-resolution transmission electron microscopy imaging and analysis suggest that this band of contrast is a cerium silicate phase with an approximate Ce:Si:O composition ratio of 1:1:3 in an amorphous nature. The slightly nonstoichiometric composition arises due to the loss of mobile oxygen within the cerium silicate phase under the current irradiation condition. This nonequilibrium phase is formed as a direct result of ion-beam-induced chemical mixing caused by ballistic collisions between the incoming ion and the lattice atoms. This may hold promise in ion beam engineering of cerium silicates for microelectronic applications e.g., the fabrication of blue LEDs.

  20. Fast ignition when heating the central part of an inertial confinement fusion target by an ion beam

    SciTech Connect (OSTI)

    Gus’kov, S. Yu., E-mail: guskov@sci.lebedev.ru [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Zmitrenko, N. V. [Russian Academy of Sciences, Keldysh Institute of Applied Mathematics (Russian Federation); Il’in, D. V.; Sherman, V. E. [St. Petersburg State Technical University (Russian Federation)

    2014-11-15T23:59:59.000Z

    We investigate the ignition and burning of a precompressed laser fusion target when it is rapidly heated by an ion beam with the formation of a temperature peak in the central part of the target. We present the results of our comprehensive numerical simulations of the problem that include the following components: (1) the target compression under the action of a profiled laser pulse, (2) the heating of the compressed target with spatially nonuniform density and temperature distributions by a beam of high-energy ions, and (3) the burning of the target with the initial spatial density distribution formed at the instant of maximum target compression and the initial spatial temperature distribution formed as a result of the compressed-target heating by an ion beam. The dependences of the threshold energies of the igniting ion beam and the thermonuclear gain on the width of the Gaussian beam ion energy spectrum have been established. The peculiarities of fast ignition by an ion beam related to the spatial distribution of parameters for the target precompressed by a laser pulse are discussed.

  1. Enhanced Self-Focusing of an Ion Beam Pulse Propagating through a Background Plasma along a Solenoidal Magnetic Field

    E-Print Network [OSTI]

    Kaganovich, Igor

    Enhanced Self-Focusing of an Ion Beam Pulse Propagating through a Background Plasma along.58.Lq, 52.59.Ã?f Neutralization and focusing of charged particle beam pulses by a background plasma form plasma elec- trons. The effects of the enhanced self-focusing are of particular importance

  2. Experimental validation of the dual positive and negative ion beam acceleration in the plasma propulsion with electronegative gases thruster

    SciTech Connect (OSTI)

    Rafalskyi, Dmytro, E-mail: dmytro.rafalskyi@lpp.polytechnique.fr; Popelier, Lara; Aanesland, Ane [Laboratoire de Physique des Plasmas, CNRS, Sorbonne Universités, UPMC Univ Paris 06, Univ Paris-Sud, Ecole Polytechnique, 91128 Palaiseau (France)

    2014-02-07T23:59:59.000Z

    The PEGASES (Plasma Propulsion with Electronegative Gases) thruster is a gridded ion thruster, where both positive and negative ions are accelerated to generate thrust. In this way, additional downstream neutralization by electrons is redundant. To achieve this, the thruster accelerates alternately positive and negative ions from an ion-ion plasma where the electron density is three orders of magnitude lower than the ion densities. This paper presents a first experimental study of the alternate acceleration in PEGASES, where SF{sub 6} is used as the working gas. Various electrostatic probes are used to investigate the source plasma potential and the energy, composition, and current of the extracted beams. We show here that the plasma potential control in such system is key parameter defining success of ion extraction and is sensitive to both parasitic electron current paths in the source region and deposition of sulphur containing dielectric films on the grids. In addition, large oscillations in the ion-ion plasma potential are found in the negative ion extraction phase. The oscillation occurs when the primary plasma approaches the grounded parts of the main core via sub-millimetres technological inputs. By controlling and suppressing the various undesired effects, we achieve perfect ion-ion plasma potential control with stable oscillation-free operation in the range of the available acceleration voltages (±350?V). The measured positive and negative ion currents in the beam are about 10?mA for each component at RF power of 100?W and non-optimized extraction system. Two different energy analyzers with and without magnetic electron suppression system are used to measure and compare the negative and positive ion and electron fluxes formed by the thruster. It is found that at alternate ion-ion extraction the positive and negative ion energy peaks are similar in areas and symmetrical in position with +/? ion energy corresponding to the amplitude of the applied acceleration voltage.

  3. Solenoid transport of a heavy ion beam for warm dense matterstudies and inertial confinement fusion

    SciTech Connect (OSTI)

    Armijo, Julien

    2006-10-01T23:59:59.000Z

    From February to July 2006, I have been doing research as a guest at Lawrence Berkeley National Laboratory (LBNL), in the Heavy Ion Fusion group. This internship, which counts as one semester in my master's program in France, I was very pleased to do it in a field that I consider has the beauty of fundamental physics, and at the same time the special appeal of a quest for a long-term and environmentally-respectful energy source. During my stay at LBNL, I have been involved in three projects, all of them related to Neutralized Drift Compression Experiment (NDCX). The first one, experimental and analytical, has consisted in measuring the effects of the eddy currents induced by the pulsed magnets in the conducting plates of the source and diagnostic chambers of the Solenoid Transport Experiment (STX, which is a subset of NDCX). We have modeled the effect and run finite-element simulations that have reproduced the perturbation to the field. Then, we have modified WARP, the Particle-In-Cell code used to model the whole experiment, in order to import realistic fields including the eddy current effects and some details of each magnet. The second project has been to take part in a campaign of WARP simulations of the same experiment to understand the leakage of electrons that was observed in the experiment as a consequence to some diagnostics and the failure of the electrostatic electron trap. The simulations have shown qualitative agreement with the measured phenomena, but are still in progress. The third project, rather theoretical, has been related to the upcoming target experiment of a thin aluminum foil heated by a beam to the 1-eV range. At the beginning I helped by analyzing simulations of the hydrodynamic expansion and cooling of the heated material. But, progressively, my work turned into making estimates for the nature of the liquid/vapor two-phase flow. In particular, I have been working on criteria and models to predict the formation of droplets, their size, and their partial or total evaporation in the expanding flow.

  4. Heavy ion beam probe advances from the first installation of the diagnostic on an RFP (invited)

    SciTech Connect (OSTI)

    Demers, D. R.; Fimognari, P. J. [Xantho Technologies, LLC, Madison, Wisconsin 53705 (United States)

    2012-10-15T23:59:59.000Z

    Heavy ion beam probes have been installed on a variety of toroidal devices, but the first and only application on a reversed field pinch is the diagnostic on the Madison Symmetric Torus. Simultaneous measurements of spatially localized equilibrium potential and fluctuations of density and potential, previously inaccessible in the core of the reversed field pinch (RFP), are now attainable. These measurements reflect the unique strength of the heavy ion beam probe (HIBP) diagnostic. They will help determine the characteristics and evolution of electrostatic fluctuations and their role in transport, and determine the relation of the interior electric field and flows. Many aspects of the RFP present original challenges to HIBP operation and inference of plasma quantities. The magnetic field contributes to a number of the issues: the comparable magnitudes of the toroidal and poloidal fields and edge reversal result in highly three-dimensional beam trajectories; partial generation of the magnetic field by plasma current cause it and hence the beam trajectories to vary with time; and temporal topology and amplitude changes are common. Associated complications include strong ultraviolet radiation and elevated particle losses that can alter functionality of the electrostatic systems and generate noise on the detectors. These complexities have necessitated the development of new operation and data analysis techniques: the implementation of primary and secondary beamlines, adoption of alternative beam steering methods, development of higher precision electrostatic system models, refinement of trajectory calculations and sample volume modeling, establishment of stray particle and noise reduction methods, and formulation of alternative data analysis techniques. These innovative methods and the knowledge gained with this system are likely to translate to future HIBP operation on large scale stellarators and tokamaks.

  5. Fabrication of planar quantum magnetic disk structure using electron beam lithography, reactive ion etching, and chemical mechanical polishing

    E-Print Network [OSTI]

    Fabrication of planar quantum magnetic disk structure using electron beam lithography, reactive ion, Department of Electrical Engineering, University of Minnesota, Minneapolis, Minnesota 55455 Received 2 June's size and location, and reactive ion etching was used to form an SiO2 template. Nickel electroplating

  6. Overview of the current spectroscopy effort on the Livermore electron beam ion traps

    SciTech Connect (OSTI)

    Beiersdorfer, P.; Lopez-Urrutia, J.C. [Lawrence Livermore National Lab., CA (United States); Brown, G. [Auburn Univ., AL (United States)] [and others

    1995-06-29T23:59:59.000Z

    An overview is given of the current spectroscopic effort on the Livermore electron beam ion trap facilities. The effort focuses on four aspects: spectral line position, line intensity, temporal evolution, and line shape. Examples of line position measurements include studies of the K-shell transitions in heliumlike Kr{sup 34+} and the 2s-2p intrashell transitions in lithiumlike Th{sup 87+} and U{sup 89+}, which provide benchmark values for testing the theory of relativistic and quantum electrodynamical contributions in high-Z ions. Examples of line intensity measurements are provided by measurements of the electron-impact excitation and dielectronic recombination cross sections of heliumlike transition-metal ions Ti{sup 20+} through CO{sup 25+}. A discussion of radiative lifetime measurements of metastable levels in heliumlike ions is given to illustrate the time-resolved spectroscopy techniques in the microsecond range. The authors also present a measurement of the spectral lineshape that illustrates the very low ion temperatures that can be achieved in an EBIT.

  7. Absolute infrared vibrational band intensities of molecular ions determined by direct laser absorption spectroscopy in fast ion beams

    SciTech Connect (OSTI)

    Keim, E.R.; Polak, M.L.; Owrutsky, J.C.; Coe, J.V.; Saykally, R.J. (Department of Chemistry, University of California, Berkeley, CA (USA))

    1990-09-01T23:59:59.000Z

    The technique of direct laser absorption spectroscopy in fast ion beams has been employed for the determination of absolute integrated band intensities ({ital S}{sup 0}{sub {ital v}}) for the {nu}{sub 3} fundamental bands of H{sub 3}O{sup +} and NH{sup +}{sub 4}. In addition, the absolute band intensities for the {nu}{sub 1} fundamental bands of HN{sup +}{sub 2} and HCO{sup +} have been remeasured. The values obtained in units of cm{sup {minus}2} atm{sup {minus}1} at STP are 1880(290) and 580(90) for the {nu}{sub 1} fundamentals of HN{sup +}{sub 2} and HCO{sup +}, respectively; and 4000(800) and 1220(190) for the {nu}{sub 3} fundamentals of H{sub 3}O{sup +} and NH{sup +}{sub 4}, respectively. Comparisons with {ital ab} {ital initio} results are presented.

  8. Experimental analysis of general ion recombination in a liquid-filled ionization chamber in high-energy photon beams

    SciTech Connect (OSTI)

    Chung, Eunah; Seuntjens, Jan [Medical Physics Unit, McGill University, Montreal General Hospital (L5-113), 1650 Cedar Avenue, Montreal, Quebec H3G 1A4 (Canada); Davis, Stephen [Department of Medical Physics, McGill University Health Centre, Montreal General Hospital (L5-112), 1650 Cedar Avenue, Montreal, Quebec H3G 1A4 (Canada)

    2013-06-15T23:59:59.000Z

    Purpose: To study experimentally the general ion recombination effect in a liquid-filled ionization chamber (LIC) in high-energy photon beams. Methods: The general ion recombination effect on the response of a micro liquid ion chamber (microLion) was investigated with a 6 MV photon beam in normal and SRS modes produced from a Varian{sup Registered-Sign} Novalis Tx{sup TM} linear accelerator. Dose rates of the linear accelerator were set to 100, 400, and 1000 MU/min, which correspond to pulse repetition frequencies of 60, 240, and 600 Hz, respectively. Polarization voltages applied to the microLion were +800 and +400 V. The relative collection efficiency of the microLion response as a function of dose per pulse was experimentally measured with changing polarization voltage and pulse repetition frequencies and was compared with the theoretically calculated value. Results: For the 60 Hz pulse repetition frequency, the experimental relative collection efficiency was not different from the theoretical one for a pulsed beam more than 0.3% for both polarization voltages. For a pulsed radiation beam with a higher pulse repetition frequency, the experimental relative collection efficiency converged to the theoretically calculated efficiency for continuous beams. This result indicates that the response of the microLion tends toward the response to a continuous beam with increasing pulse repetition frequency of a pulsed beam because of low ion mobility in the liquid. Conclusions: This work suggests an empirical method to correct for differences in general ion recombination of a LIC between different radiation fields. More work is needed to quantitatively explain the LIC general ion recombination behavior in pulsed beams generated from linear accelerators.

  9. Interface and process for enhanced transmission of non-circular ion beams between stages at unequal pressure

    DOE Patents [OSTI]

    Tang, Keqi (Richland, WA); Shvartsburg, Alexandre A. (Richland, WA); Smith, Richard D. (Richland, WA)

    2008-03-04T23:59:59.000Z

    The invention discloses a new interface with non-circular conductance limit aperture(s) useful for effective transmission of non-circular ion beams between stages with different gas pressure. In particular, the invention provides an improved coupling of field asymmetric waveform ion mobility spectrometry (FAIMS) analyzers of planar or side-to-side geometry to downstream stages such as mass spectrometry or ion mobility spectrometry. In this case, the non-circular aperture is rectangular; other geometries may be optimum in other applications. In the preferred embodiment, the non-circular aperture interface is followed by an electrodynamic ion funnel that may focus wide ion beams of any shape into tight circular beams with virtually no losses. The jet disrupter element of the funnel may also have a non-circular geometry, matching the shape of arriving ion beam. The improved sensitivity of planar FAIMS/MS has been demonstrated in experiments using a non-contiguous elongated aperture but other embodiments (e.g., with a contiguous slit aperture) may be preferable, especially in conjunction with an ion funnel operated at high pressures.

  10. A prototype compton camera for in-vivo dosimetry of ion beam cancer irradiation

    SciTech Connect (OSTI)

    Kormoll, T. [Technische Universitaet Dresden, OncoRay, PF 86, 013307 Dresden (Germany); Fiedler, F. [Helmholtzzentrum Dresden-Rossendorf, Inst. of Radiation Physics, PF 5103119, 013314 Dresden (Germany); Golnik, C. [Technische Universitaet Dresden, OncoRay, PF 86, 013307 Dresden (Germany); Heidel, K.; Kempe, M. [Helmholtzzentrum Dresden-Rossendorf, Inst. of Radiation Physics, PF 5103119, 013314 Dresden (Germany); Schoene, S.; Sobiella, M. [Helmholtzzentrum Dresden-Rossendorf, Inst. of Radiation Physics, PF 5103119, 013314 Dresden (Germany); Zuber, K. [Technische Universitaet Dresden, Inst. of Nuclear and Particle Physics, Zellescher Weg 19, 013069 Dresden (Germany); Enghardt, W. [Technische Universitaet Dresden, OncoRay, PF 86, 013307 Dresden (Germany); Helmholtzzentrum Dresden-Rossendorf, Inst. of Radiation Physics, PF 5103119, 013314 Dresden (Germany)

    2011-07-01T23:59:59.000Z

    Three-dimensional in-vivo dose monitoring of ion beam cancer irradiation can improve the quality of treatment. For this purpose we investigate the feasibility of imaging the single photon emissions due to nuclear reactions of projectiles with target nuclei (in-beam SPECT). A suitable imaging technique in the energy range of the emitted gamma rays is the Compton camera. A prototype based on prior simulations is currently under construction. Te system comprises two CdZnTe cross-strip detectors with steering grid and depth-of-interaction capability and one segmented LSO scintillator crystal with modified Anger light readout. We present the concept of the system including the front-end and DAQ electronics as well as first measurements. (authors)

  11. Exchange bias in polycrystalline magnetite films made by ion-beam assisted deposition

    SciTech Connect (OSTI)

    Kaur, Maninder; Qiang, You [Department of Physics, University of Idaho, Moscow, Idaho 83844 (United States); Jiang, Weilin [Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Burks, Edward C.; Liu, Kai [Department of Physics, University of California, Davis, California 95616 (United States); Namavar, Fereydoon [University of Nebraska Medical Center, Omaha, Nebraska 68198 (United States); McCloy, John S. [Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); School of Mechanical and Materials Engineering, Washington State University, Pullman, Washington 98163 (United States)

    2014-11-07T23:59:59.000Z

    Iron oxide films were produced using ion-beam-assisted deposition, and Raman spectroscopy and x-ray diffraction indicate single-phase magnetite. However, incorporation of significant fractions of argon in the films from ion bombardment is evident from chemical analysis, and Fe/O ratios are lower than expected from pure magnetite, suggesting greater than normal disorder. Low temperature magnetometry and first-order reversal curve measurements show strong exchange bias, which likely arises from defects at grain boundaries, possibly amorphous, creating frustrated spins. Since these samples contain grains ?6?nm, a large fraction of the material consists of grain boundaries, where spins are highly disordered and reverse independently with external field.

  12. Excitation of dust acoustic waves by an ion beam in a plasma cylinder with negatively charged dust grains

    SciTech Connect (OSTI)

    Sharma, Suresh C. [Department of Applied Physics, Delhi Technological University (DTU), Shahbad Daulatpur, Bawana Road, Delhi-42 (India); Kaur, Daljeet [Department of Physics, Guru Teg Bahadur Institute of Technology, Rajouri Garden, New Delhi (India); Gahlot, Ajay [Department of Physics, Maharaja Surajmal Institute of Technology, Janakpuri, New Delhi (India); Sharma, Jyotsna [Department of Physics, KIIT College of Engineering, Bhondsi Gurgaon 122102 (India)

    2014-10-15T23:59:59.000Z

    An ion beam propagating through a plasma cylinder having negatively charged dust grains drives a low frequency electrostatic dust acoustic wave (DAW) to instability via Cerenkov interaction. The unstable wave frequencies and the growth rate increase with the relative density of negatively charged dust grains. The growth rate of the unstable mode scales to the one-third power of the beam density. The real part of the frequency of the unstable mode increases with the beam energy and scales to almost one-half power of the beam energy. The phase velocity, frequency, and wavelength results of the unstable mode are in compliance with the experimental observations.

  13. PROJECT-SPECIFIC TYPE A VERIFICATION FOR THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PHASE 3 TRENCH 1, BROOKHAVEN NATIONAL LABORATORY UPTON, NEW YORK

    SciTech Connect (OSTI)

    E.M. Harpenau

    2010-12-15T23:59:59.000Z

    5098-SR-05-0 PROJECT-SPECIFIC TYPE A VERIFICATION FOR THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PHASE 3 TRENCH 1 BROOKHAVEN NATIONAL LABORATORY

  14. PROJECT-SPECIFIC TYPE A VERIFICATION FOR THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PHASE 3 TRENCH 5, BROOKHAVEN NATIONAL LABORATORY UPTON, NEW YORK

    SciTech Connect (OSTI)

    P.C. Weaver

    2010-11-03T23:59:59.000Z

    5098-SR-04-0 PROJECT-SPECIFIC TYPE A VERIFICATION FOR THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PHASE 3 TRENCH 5, BROOKHAVEN NATIONAL LABORATORY

  15. TITAN's Digital RFQ Ion Beam Cooler and Buncher, Operation and Performance

    E-Print Network [OSTI]

    T. Brunner; M. J. Smith; M. Brodeur; S. Ettenauer; A. T. Gallant; V. V. Simon; A. Chaudhuri A. Lapierre; E. Mané; R. Ringle; M. C. Simon; J. A. Vaz; P. Delheij; M. Good; M. R. Pearson; J. Dilling

    2012-02-07T23:59:59.000Z

    We present a description of the Radio Frequency Quadrupole (RFQ) ion trap built as part of the TITAN facility. It consists of a gas-filled, segmented, linear Paul trap and is the first stage of the TITAN setup with the purpose of cooling and bunching radioactive ion beams delivered from ISAC-TRIUMF. This is the first such device to be driven digitally, i.e., using a high voltage ($V_{pp} = \\rm{400 \\, V}$), wide bandwidth ($0.2 < f < 1.2 \\, \\rm{MHz}$) square-wave as compared to the typical sinusoidal wave form. Results from the commissioning of the device as well as systematic studies with stable and radioactive ions are presented including efficiency measurements with stable $^{133}$Cs and radioactive $^{124, 126}$Cs. A novel and unique mode of operation of this device is also demonstrated where the cooled ion bunches are extracted in reverse mode, i.e., in the same direction as previously injected.

  16. Helicon plasma generator-assisted surface conversion ion source for the production of H{sup -} ion beams at the Los Alamos Neutron Science Center

    SciTech Connect (OSTI)

    Tarvainen, O.; Rouleau, G.; Keller, R.; Geros, E.; Stelzer, J.; Ferris, J. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2008-02-15T23:59:59.000Z

    The converter-type negative ion source currently employed at the Los Alamos Neutron Science Center (LANSCE) is based on cesium enhanced surface production of H{sup -} ion beams in a filament-driven discharge. In this kind of an ion source the extracted H{sup -} beam current is limited by the achievable plasma density which depends primarily on the electron emission current from the filaments. The emission current can be increased by increasing the filament temperature but, unfortunately, this leads not only to shorter filament lifetime but also to an increase in metal evaporation from the filament, which deposits on the H{sup -} converter surface and degrades its performance. Therefore, we have started an ion source development project focused on replacing these thermionic cathodes (filaments) of the converter source by a helicon plasma generator capable of producing high-density hydrogen plasmas with low electron energy. In our studies which have so far shown that the plasma density of the surface conversion source can be increased significantly by exciting a helicon wave in the plasma, and we expect to improve the performance of the surface converter H{sup -} ion source in terms of beam brightness and time between services. The design of this new source and preliminary results are presented, along with a discussion of physical processes relevant for H{sup -} ion beam production with this novel design. Ultimately, we perceive this approach as an interim step towards our long-term goal, combining a helicon plasma generator with an SNS-type main discharge chamber, which will allow us to individually optimize the plasma properties of the plasma cathode (helicon) and H{sup -} production (main discharge) in order to further improve the brightness of extracted H{sup -} ion beams.

  17. Design of the channel for irradiation of materials with highly charged ion beams obtained from the mVINIS ion source

    SciTech Connect (OSTI)

    Siljegovic, M.; Dobrosavljevic, A.; Draganic, I.; Cizmic, B.; Jelic, G. [Laboratory of Physics (010), Vinca Institute of Nuclear Sciences, P.O. Box 522, 11001 Belgrade (Serbia and Montenegro)

    2006-03-15T23:59:59.000Z

    The low-energy part of the TESLA Accelerator Installation comprises an electron cyclotron resonance ion source (the mVINIS ion source) and the channel for modification of materials (L3A). The L3A channel is long and has low beam transmission (30%-50%), so it is not suitable for high fluence implantations (over 10{sup 16} cm{sup -2}). Therefore, we are planning to introduce an experimental channel (L4), close to the mVINIS Ion Source, where we shall be able to achieve high beam currents on the target and, consequently, irradiation of materials to high fluences. During the ion implantation, we shall be able to measure fluence rate, achieve uniform fluence distribution by a mechanism for x and y sample movements, and control the sample temperature in the range of 0-200 deg. C.

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

    SciTech Connect (OSTI)

    Dorf, Mikhail A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Davidson, Ronald C.; Kaganovich, Igor D.; Startsev, Edward A. [Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

    2012-05-15T23:59:59.000Z

    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 {approx} 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.

  19. Ion Beam Sputter Fabrication of Micro-Grooving and Micro-Threading Tools

    SciTech Connect (OSTI)

    ADAMS,DAVID P.; VASILE,M.J.; KRISHNAN,A.S.M.

    1999-11-05T23:59:59.000Z

    This paper presents techniques for fabricating microscopic, nonplanar features in a variety of materials. Micro-grooving and micro-threading tools having cutting dimensions of 10-30{micro}m are made by focused ion beam sputtering and used in ultra-precision machining. Tool fabrication involves directing a 20 keV gallium beam at polished cylindrical punches made of cobalt M42 high-speed steel or C2 tungsten carbide. This creates cutting edges having radii of curvature less than 0.4 {micro}m, and rake features similar to conventional lathe tools. Clearance for minimizing frictional drag of a tool results from the sputter yield dependence on ion herd target incidence angle. Numerically controlled, ultra-precision machining with micro-grooving tools results in a close matching between tool width and feature size. Microtools controllably machine 13 {micro}m wide, 4 {micro}m deep, helical grooves in polymethyl methacrylate and 6061-T6 Al cylindrical substrates. Micro-grooving tools also fabricate sinusoidal waveform features in polished metal substrates.

  20. High Power Molten Targets for Radioactive Ion Beam Production: from Particle Physics to Medical Applications

    E-Print Network [OSTI]

    De Melo Mendonca, T M

    2014-01-01T23:59:59.000Z

    Megawatt-class molten targets, combining high material densities and good heat transfer properties are being considered for neutron spallation sources, neutrino physics facilities and radioactive ion beam production. For this last category of facilities, in order to cope with the limitation of long diffusion times affecting the extraction of short-lived isotopes, a lead-bismuth eutectic (LBE) target loop equipped with a diffusion chamber has been proposed and tested offline during the EURISOL design study. To validate the concept, a molten LBE loop is now in the design phase and will be prototyped and tested on-line at CERN-ISOLDE. This concept was further extended to an alternative route to produce 1013 18Ne/s for the Beta Beams, where a molten salt loop would be irradiated with 7 mA, 160 MeV proton beam. Some elements of the concept have been tested by using a molten fluoride salt static unit at CERNISOLDE. The investigation of the release and production of neon isotopes allowed the measurement of the diffu...

  1. Introduction of the MC3-II/GP system, medium current ion implanter with enhanced multi-charge beam current

    SciTech Connect (OSTI)

    Koike, Masazumi; Sato, Fumiaki; Sano, Makoto; Kawatsu, Sho; Kariya, Hiroyuki; Kimura, Yasuhiko; Kudo, Tetsuya; Shiraishi, Miyuki; Shinozuka, Masamitsu; Takahashi, Yuji; Ishida, Yuji; Tsukihara, Mitsukuni; Ueno, Kazuyoshi; Sugitani, Michiro [SEN Corporation, 1501, Imazaike, Saijo, Ehime, 799-1362 (Japan)

    2012-11-06T23:59:59.000Z

    The MC3-II/GP is a leading-edge single-wafer medium-current ion implanter, newly developed by SEN Corporation. It demonstrates exceptional productivity based on a high speed wafer-handling station and enhanced beam current. It covers a substantively wider energy range in order to fully meet advanced device requirements. Retaining the superior features of the MC3-II/WR, the MC3-II/GP provides a remarkable increase of multiply-charged beam current coupled with longer ion source lifetime. Another advanced feature of the MC3-II/GP is a 30 second or 14% reduction in auto beam setup time. These improvements enable a fabrication line to reduce the total number of ion implanters and dramatically reduce COO.

  2. Nanostructured ion beam-modified Ge films for high capacity Li ion battery N. G. Rudawski, B. L. Darby, B. R. Yates, K. S. Jones, R. G. Elliman et al.

    E-Print Network [OSTI]

    Florida, University of

    Nanostructured ion beam-modified Ge films for high capacity Li ion battery anodes N. G. Rudawski, B photoelectrochemical cells Appl. Phys. Lett. 100, 084104 (2012) Synthesis and characterization of Nd4+xFe72Co5Ga2B17-x://apl.aip.org/authors #12;Nanostructured ion beam-modified Ge films for high capacity Li ion battery anodes N. G. Rudawski,1

  3. Space-Charge Limits on the Transport of Ion Beams in a Long Alternating Gradient System

    E-Print Network [OSTI]

    Tiefenback, M.G.

    2011-01-01T23:59:59.000Z

    term stability of the transport of cold, high-current beams,beam. The cold-beam ideal case for this transport is called

  4. H{sup -} beam extraction from a cesium seeded field effect transistor based radio frequency negative hydrogen ion source

    SciTech Connect (OSTI)

    Ando, A.; Matsuno, T.; Funaoi, T.; Tanaka, N. [School of Engineering, Tohoku University, Sendai 980-8579 (Japan); Tsumori, K.; Takeiri, Y. [National Institute for Fusion Science, Toki 509-5292 (Japan)

    2012-02-15T23:59:59.000Z

    H{sup -} beam was successfully extracted from a cesium seeded ion source operated using a field effect transistor inverter power supply as a radio frequency (RF) wave source. High density hydrogen plasma more than 10{sup 19} m{sup -3} was obtained using an external type antenna with RF frequency of lower than 0.5 MHz. The source was isolated by an isolation transformer and H{sup -} ion beam was extracted from a single aperture. Acceleration current and extraction current increased with the increase of extraction voltage. Addition of a small amount of cesium vapor into the source enhanced the currents.

  5. Angular-divergence calculation for Experimental Advanced Superconducting Tokamak neutral beam injection ion source based on spectroscopic measurements

    SciTech Connect (OSTI)

    Chi, Yuan, E-mail: jtext@hust.edu.cn [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China) [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China); Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Hu, Chundong [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)] [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Zhuang, Ge [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China)] [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2014-02-15T23:59:59.000Z

    Calorimetric method has been primarily applied for several experimental campaigns to determine the angular divergence of high-current ion source for the neutral beam injection system on the Experimental Advanced Superconducting Tokamak (EAST). A Doppler shift spectroscopy has been developed to provide the secondary measurement of the angular divergence to improve the divergence measurement accuracy and for real-time and non-perturbing measurement. The modified calculation model based on the W7AS neutral beam injectors is adopted to accommodate the slot-type accelerating grids used in the EAST's ion source. Preliminary spectroscopic experimental results are presented comparable to the calorimetrically determined value of theoretical calculation.

  6. Development of Fragmented Low-Z Ion Beams for the NA61 Experiment at the CERN SPS

    E-Print Network [OSTI]

    Efthymiopoulos, I; Bohl, T; Breuker, H; Calviani, M; Manglunki, D; Mataguez, S; Maury, S; Valderanis, C; Cornelis, K; Spanggaard, J; Cettour-Cave, S; Gazdzicki, M; Seyboth, P; Guber, F; Ivashkin, A

    2011-01-01T23:59:59.000Z

    The NA61 experiment, aims to study the properties of the onset of deconfinement at low SPS energies and to find signatures of the critical point of strongly interacting matter. A broad range in T-?B phase diagram will be covered by performing an energy (13A-158AGeV/c) and system size (p+p, Be+Be, Ar+Ca, Xe+La) scan. In a first phase, fragmented ion beams of 7Be or 11C produced as secondaries with the same momentum per nucleon when the incident primary Pb-ion beam hits a thin Be target will be used. The H2 beam line that transports the beam to the experiment acts as a double spectrometer which combined with a new thin target (degrader) where fragments loose energy proportional to the square of their charge allows the separation of the wanted A/Z fragments. Thin scintillators and TOF measurement for the low energy points are used as particle identification devices. In this paper results from the first test of the fragmented ion beam done in 2010 will be presented showing that a pure Be beam can be obtained sa...

  7. Passive tailoring of laser-accelerated ion beam cut-off energy by using double foil assembly

    SciTech Connect (OSTI)

    Chen, S. N., E-mail: sophia.chen@polytechnique.edu; Brambrink, E.; Mancic, A.; Romagnani, L.; Audebert, P.; Fuchs, J., E-mail: julien.fuchs@polytechnique.fr [Laboratoire pour l'Utilisation des Lasers Intenses, UMR 7605 CNRS-CEA-École Polytechnique-Université Paris VI, Palaiseau (France); Robinson, A. P. L. [Central Laser Facility, STFC Rutherford-Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX (United Kingdom)] [Central Laser Facility, STFC Rutherford-Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX (United Kingdom); Antici, P. [Laboratoire pour l'Utilisation des Lasers Intenses, UMR 7605 CNRS-CEA-École Polytechnique-Université Paris VI, Palaiseau (France) [Laboratoire pour l'Utilisation des Lasers Intenses, UMR 7605 CNRS-CEA-École Polytechnique-Université Paris VI, Palaiseau (France); Dipartimento SBAI, Università di Roma « La Sapienza », Via Scarpa 14-16, 00165 Roma (Italy); INRS-Énergie et Matériaux, 1650 bd. L. Boulet, Varennes, J3X1S2 Québec (Canada); D'Humières, E. [Physics Department, MS-220, University of Nevada, Reno, Nevada 89557 (United States) [Physics Department, MS-220, University of Nevada, Reno, Nevada 89557 (United States); Centre de Physique Théorique, CNRS-Ecole Polytechnique, 91128 Palaiseau (France); University of Bordeaux—CNRS—CEA, CELIA, UMR5107, 33405 Talence (France); Gaillard, S. [Physics Department, MS-220, University of Nevada, Reno, Nevada 89557 (United States)] [Physics Department, MS-220, University of Nevada, Reno, Nevada 89557 (United States); Grismayer, T.; Mora, P. [Centre de Physique Théorique, CNRS-Ecole Polytechnique, 91128 Palaiseau (France)] [Centre de Physique Théorique, CNRS-Ecole Polytechnique, 91128 Palaiseau (France); Pépin, H. [INRS-Énergie et Matériaux, 1650 bd. L. Boulet, Varennes, J3X1S2 Québec (Canada)] [INRS-Énergie et Matériaux, 1650 bd. L. Boulet, Varennes, J3X1S2 Québec (Canada)

    2014-02-15T23:59:59.000Z

    A double foil assembly is shown to be effective in tailoring the maximum energy produced by a laser-accelerated proton beam. The measurements compare favorably with adiabatic expansion simulations, and particle-in-cell simulations. The arrangement proposed here offers for some applications a simple and passive way to utilize simultaneously highest irradiance lasers that have best laser-to-ion conversion efficiency while avoiding the production of undesired high-energy ions.

  8. Electron-Impact Ionization of Multicharged Ions: Cross-Sections Data from Oak Ridge National Laboratory (ORNL) and the Controlled Fusion Atomic Data Center (CFADC)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    This website presents experimental ionization cross sections measured using the Electron-Ion Crossed Beams apparatus in the Multicharged Ion Research Facility (MIRF) at the Physics Division of Oak Ridge National Laboratory (ORNL). The data are given in both graphical and tabular form along with the reference to the original publication of the experimental results. Also presented in the figures are theoretical cross sections supporting the experiments. For details of the theoretical work, refer to the original publication given for the particular experiment. These pages are based primarily on three technical memorandums issued by ORNL: 1(D. H. Crandall, R. A. Phaneuf, and D. C. Gregory, Electron Impact Ionization of Multicharged Ions, ORNL/TM-7020, Oak Ridge National Laboratory, 1979; 2) D. C. Gregory, D. H. Crandall, R. A. Phaneuf, A. M. Howald, G. H. Dunn, R. A. Also presented are more recent (1993-present) data, both published and unpublished. The data pages feature dynamic plotting, allowing the user to choose which sets of data to plot and zoom in on regions of interest within the plot. [Taken from http://www-cfadc.phy.ornl.gov/xbeam/index.html

  9. Design of quantum dot lattices in amorphous matrices by ion beam irradiation

    SciTech Connect (OSTI)

    Buljan, M.; Bogdanovic-Radovic, I.; Karlusic, M.; Desnica, U. V.; Radic, N.; Jaksic, M.; Salamon, K.; Drazic, G.; Bernstorff, S.; Holy, V. [Rudjer Boskovic Institute, Bijenicka cesta 54, HR-10000 Zagreb (Croatia); Institute of Physics, Bijenicka cesta 46, HR-10000 Zagreb (Croatia); Jozef Stefan Institute, Jamova 39, SLO-1000 Ljubljana (Slovenia); Sincrotrone Trieste, I-34149 Basovizza (Italy); Charles University in Prague, CZ-12116 Prague (Czech Republic)

    2011-10-15T23:59:59.000Z

    We report on the highly controllable self-assembly of semiconductor quantum dots and metallic nanoparticles in a solid amorphous matrix, induced by ion beam irradiation of an amorphous multilayer. We demonstrate experimentally and theoretically a possibility to tune the basic structural properties of the quantum dots in a wide range. Furthermore, the sizes, distances, and arrangement type of the quantum dots follow simple equations dependent on the irradiation and the multilayer properties. We present a Monte Carlo model for the simulation and prediction of the structural properties of the materials formed by this method. The presented results enable engineering and simple production of functional materials or simple devices interesting for applications in nanotechnology.

  10. The giant ion sources of neutral-beam injectors for fusion

    SciTech Connect (OSTI)

    Kunkel, W.B.

    1989-07-01T23:59:59.000Z

    All large tokamak fusion experiments today use auxiliary heating by multi-megawatt beams of neutral isotopes of hydrogen injected with energies in the neighborhood of 100 keV per atom. This requires reliable operation of large ion sources, each delivering many tens of amperes of protons or deuterons, and soon even tritons. For meaningful experiments these sources must operate with pulse durations measured in seconds, although the duty factor may still be small. It is remarkable that the successful sources developed in Europe, Japan and the US are all very similar in basic design: the plasma is produced by diffuse low-pressure high-current discharges in magnetic multipole buckets'' was distributed thermionically emitting cathodes. This paper briefly reviews the principal considerations and the basic physics of these sources, and summarizes the collective experience to date and describes the impressive recent performance of the US Common Long Pulse Source, as a specific example. 20 refs., 6 figs., 2 tabs.

  11. Characterization of zirconia- and niobia-silica mixture coatings produced by ion-beam sputtering

    SciTech Connect (OSTI)

    Melninkaitis, Andrius; Tolenis, Tomas; Mazule, Lina; Mirauskas, Julius; Sirutkaitis, Valdas; Mangote, Benoit; Fu Xinghai; Zerrad, Myriam; Gallais, Laurent; Commandre, Mireille; Kicas, Simonas; Drazdys, Ramutis

    2011-03-20T23:59:59.000Z

    ZrO{sub 2}-SiO{sub 2} and Nb{sub 2}O{sub 5}-SiO{sub 2} mixture coatings as well as those of pure zirconia (ZrO{sub 2}), niobia (Nb{sub 2}O{sub 5}), and silica (SiO{sub 2}) deposited by ion-beam sputtering were investigated. Refractive-index dispersions, bandgaps, and volumetric fractions of materials in mixed coatings were analyzed from spectrophotometric data. Optical scattering, surface roughness, nanostructure, and optical resistance were also studied. Zirconia-silica mixtures experience the transition from crystalline to amorphous phase by increasing the content of SiO{sub 2}. This also results in reduced surface roughness. All niobia and silica coatings and their mixtures were amorphous. The obtained laser-induced damage thresholds in the subpicosecond range also correlates with respect to the silica content in both zirconia- and niobia-silica mixtures.

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

    E-Print Network [OSTI]

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

    2002-01-01T23:59:59.000Z

    neutralization on heavy-ion fusion chamber transport,” totechniques for heavy ion fusion chamber transport,” Nucl.liquid heavy-ion fusion target chambers,” Fusion Technol.

  13. INACTIVATION OF HUMAN KIDNEY CELLS BY HIGH-ENERGY MONOENERGETIC HEAVY-ION BEAMS

    E-Print Network [OSTI]

    Blakely, E.A.

    2011-01-01T23:59:59.000Z

    measured in the second ion chamber to that measuredin the monitor ion chamber.collector of the second ion chamber (l-cm diameter) is used

  14. Control of power characteristics of ion flow in plasma-etching reactor based on beam-plasma discharge

    SciTech Connect (OSTI)

    Isaev, N. V.; Klykov, I. L.; Shustin, E. G., E-mail: shustin@ms.ire.rssi.ru [Russian Academy of Sciences, Kotel'nikov Institute of Radio Engineering and Electronics (Fryazino Branch) (Russian Federation)

    2011-12-15T23:59:59.000Z

    It is shown that on the basis of the earlier revealed effect of generating the ion flow in the beam-plasma discharge from the discharge axis, a plasma processing reactor can be created for low-energy etching of semiconductor structures. The possibility of easily controlling the density and energy of ion flow by means of varying the potential of the discharge collector is demonstrated. The charge compensation of the ion flow incident on the nonconducting surface is implemented using the modulation of the potential of the substrate holder as well as the plasma-potential modulation.

  15. Electron density profile measurements at a self-focusing ion beam with high current density and low energy extracted through concave electrodes

    SciTech Connect (OSTI)

    Fujiwara, Y., E-mail: s1220908@u.tsukuba.ac.jp; Nakamiya, A.; Sakakita, H. [Department of Engineering Mechanics and Energy, University of Tsukuba, Ibaraki (Japan) [Department of Engineering Mechanics and Energy, University of Tsukuba, Ibaraki (Japan); Innovative Plasma Technologies Group, National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki (Japan); Hirano, Y. [Innovative Plasma Technologies Group, National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki (Japan) [Innovative Plasma Technologies Group, National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki (Japan); Laboratory of Physics, College of Science and Technologies, Nihon University, Tokyo (Japan); Kiyama, S.; Koguchi, H. [Innovative Plasma Technologies Group, National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki (Japan)] [Innovative Plasma Technologies Group, National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki (Japan)

    2014-02-15T23:59:59.000Z

    The self-focusing phenomenon has been observed in a high current density and low energy ion beam. In order to study the mechanism of this phenomenon, a special designed double probe to measure the electron density and temperature is installed into the chamber where the high current density ion beam is injected. Electron density profile is successfully measured without the influence of the ion beam components. Estimated electron temperature and density are ?0.9 eV and ?8 × 10{sup 8} cm{sup ?3} at the center of ion beam cross section, respectively. It was found that a large amount of electrons are spontaneously accumulated in the ion beam line in the case of self-forcing state.

  16. Source fabrication and lifetime for Li{sup +} ion beams extracted from alumino-silicate sources

    SciTech Connect (OSTI)

    Roy, Prabir K.; Greenway, Wayne G.; Kwan, Joe W. [Lawrence Berkeley National Laboratory (LBNL), One Cyclotron Road, Berkeley, California 94720 (United States)

    2012-04-15T23:59:59.000Z

    A space-charge-limited beam with current densities (J) exceeding 1 mA/cm{sup 2} have been measured from lithium alumino-silicate ion sources at a temperature of {approx}1275 deg. C. At higher extraction voltages, the source appears to become emission limited with J{>=} 1.5 mA/cm{sup 2}, and J increases weakly with the applied voltage. A 6.35 mm diameter source with an alumino-silicate coating, {<=}0.25 mm thick, has a measured lifetime of {approx}40 h at {approx}1275 deg. C, when pulsed at 0.05 Hz and with pulse length of {approx}6 {mu}s each. At this rate, the source lifetime was independent of the actual beam charge extracted due to the loss of neutral atoms at high temperature. The source lifetime increases with the amount of alumino-silicate coated on the emitting surface, and may also be further extended if the temperature is reduced between pulses.

  17. Source fabrication and lifetime for Li{sup +} ion beams extracted from alumino-silicate sources

    SciTech Connect (OSTI)

    Greenway, W. G.; Kwan, J. W.

    2012-02-10T23:59:59.000Z

    A space-charge-limited beam with current densities (J) exceeding 1 mA/cm{sup 2} have been measured from lithium alumino-silicate ion sources at a temperature of ?1275{degrees}C. At higher extraction voltages, the source appears to become emission limited with J ? 1.5 mA/cm{sup 2}, and J increases weakly with the applied voltage. A source with an alumino-silicate coating 6.35 mm in diameter and ?0.25 mm thick, has a lifetime of ?40 hours at ?1275{degrees}C, when pulsed at 0.05 Hz and with pulse length of ?6 ?s each. At this rate, the source lifetime was independent of the actual beam charge extracted due to the loss of neutral atoms at high temperature. Furthermore, the source lifetime increases with the amount of alumino-silicate coated on the emitting surface, and may also be extended if the temperature is reduced between pulses.

  18. Source fabrication and lifetime for Li+ ion beams extracted from alumino-silicate sources

    SciTech Connect (OSTI)

    Roy, Prabir K.; Greenway, Wayne G.; Kwan, Joe W

    2012-03-05T23:59:59.000Z

    A space-charge-limited beam with current densities (J) exceeding 1 mA/cm{sup 2} have been measured from lithium alumino-silicate ion sources at a temperature of #24;~1275#14;{degrees} C. At higher extraction voltages, the source appears to become emission limited with J #21;{>=} 1.5 mA/cm{sup 2}, and J increases weakly with the applied voltage. A 6.35 mm diameter source with an alumino-silicate coating, {<=}#20;0.25 mm thick, has a measured lifetime of ~#24;40 hours at ~#24;1275#14;{degrees} C, when pulsed at 0.05 Hz and with pulse length of #24;~6 μs each. At this rate, the source lifetime was independent of the actual beam charge extracted due to the loss of neutral atoms at high temperature. The source lifetime increases with the amount of alumino-silicate coated on the emitting surface, and may also be further extended if the temperature is reduced between pulses.

  19. Comparison of experimental data and three-dimensional simulations of ion beam neutralization from the Neutralized Transport Experiment

    E-Print Network [OSTI]

    Gilson, Erik

    . Greenway, B. Logan, R. MacGill, D. Shuman et al., Phys. Rev. ST-Accel. Beams 7, 083501 2004 . Preformed-dimensional 3D particle-in-cell simulations. Along with detailed target images, 4D phase-space data with perveance,16 it is possible to scale the experi- ment to lower mass ions and particle energy as well

  20. Beta-induced Alfven-Acoustic Eigenmodes in NSTX and DIII-D Driven by Beam Ions

    E-Print Network [OSTI]

    Beta-induced Alfv´en-Acoustic Eigenmodes in NSTX and DIII-D Driven by Beam Ions N. N. Gorelenkov´en Cascades) · BAAEmodes (Beta-induced Alfv´en- acoustic Eigenmodes) New BAAE modes (Gorelenkov- bilities: · TAE/RSAEs and (toroidicity-induced/ reversed shear AEs - Alfv´en Cascades) · BAAEmodes (Beta

  1. P-113 / X. Li P-113: Ferroelectric LC Aligned on SiO2 Thin Films Using the Ion Beam

    E-Print Network [OSTI]

    Water Bay, Kowloon, Hong Kong A. Khokhlov and E. Khokhlov Izovac Ltd, Belarus Abstract The uniform" (before electrical treatment) and "quazi- bookshelf" (after electrical treatment) were studied of investigation of the alignment of FLC materials on the SiO2 films produced by the ion-beam deposition for LC

  2. Abstract ID: WED-AM-B3 Use of ion beam analysis techniques to characterise iron corrosion

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Abstract ID: WED-AM-B3 Use of ion beam analysis techniques to characterise iron corrosion under 12 MeV proton irradiation on the corrosion behaviour of pure iron. Oxygen and hydrogen playing a crucial role during the corrosion process have been specifically investigated. Heavy desaerated water

  3. Focused ion beam micromilling of GaN and related substrate materials ,,sapphire, SiC, and Si...

    E-Print Network [OSTI]

    Steckl, Andrew J.

    Focused ion beam micromilling of GaN and related substrate materials ,,sapphire, SiC, and Si... A. In addition, we report similar results for materials currently utilized as substrates for GaN growth. II-0030 Received 15 October 1998; accepted 18 December 1998 Micromilling of GaN films has been obtained using a Ga

  4. Space-charge compensation measurements in electron cyclotron resonance ion source low energy beam transport lines with a retarding field analyzer

    SciTech Connect (OSTI)

    Winklehner, D.; Leitner, D., E-mail: leitnerd@nscl.msu.edu; Cole, D.; Machicoane, G.; Tobos, L. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)] [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)

    2014-02-15T23:59:59.000Z

    In this paper we describe the first systematic measurement of beam neutralization (space charge compensation) in the ECR low energy transport line with a retarding field analyzer, which can be used to measure the potential of the beam. Expected trends for the space charge compensation levels such as increase with residual gas pressure, beam current, and beam density could be observed. However, the overall levels of neutralization are consistently low (<60%). The results and the processes involved for neutralizing ion beams are discussed for conditions typical for ECR injector beam lines. The results are compared to a simple theoretical beam plasma model as well as simulations.

  5. Beam dynamics of the Neutralized Drift Compression Experiment-II (NDCX-II), a novel pulse-compressing ion accelerator

    SciTech Connect (OSTI)

    Friedman, A; Barnard, J J; Cohen, R H; Grote, D P; Lund, S M; Sharp, W M; Faltens, A; Henestroza, E; Jung, J; Kwan, J W; Lee, E P; Leitner, M A; Logan, B G; Vay, J; Waldron, W L; Davidson, R C; Dorf, M; Gilson, E P; Kaganovich, I

    2009-11-19T23:59:59.000Z

    Intense beams of heavy ions are well suited for heating matter to regimes of emerging interest. A new facility, NDCX-II, will enable studies of warm dense matter at {approx}1 eV and near-solid density, and of heavy-ion inertial fusion target physics relevant to electric power production. For these applications the beam must deposit its energy rapidly, before the target can expand significantly. To form such pulses, ion beams are temporally compressed in neutralizing plasma; current amplification factors of {approx}50-100 are routinely obtained on the Neutralized Drift Compression Experiment (NDCX) at LBNL. In the NDCX-II physics design, an initial non-neutralized compression renders the pulse short enough that existing high-voltage pulsed power can be employed. This compression is first halted and then reversed by the beam's longitudinal space-charge field. Downstream induction cells provide acceleration and impose the head-to-tail velocity gradient that leads to the final neutralized compression onto the target. This paper describes the discrete-particle simulation models (1-D, 2-D, and 3-D) employed and the space-charge-dominated beam dynamics being realized.

  6. Beam dynamics of the Neutralized Drift Compression Experiment-II (NDCX-II),a novel pulse-compressing ion accelerator

    SciTech Connect (OSTI)

    Friedman, A.; Barnard, J.J.; Cohen, R.H.; Grote, D.P.; Lund, S.M.; Sharp, W.M.; Faltens, A.; Henestroza, E.; Jung, J.-Y.; Kwan, J.W.; Lee, E.P.; Leitner, M.A.; Logan, B.G.; Vay, J.-L.; Waldron, W.L.; Davidson, R.C.; Dorf, M.; Gilson, E.P.; Kaganovich, I.D.

    2009-12-19T23:59:59.000Z

    Intense beams of heavy ions are well suited for heating matter to regimes of emerging interest. A new facility, NDCX-II, will enable studies of warm dense matter at {approx}1 eV and near-solid density, and of heavy-ion inertial fusion target physics relevant to electric power production. For these applications the beam must deposit its energy rapidly, before the target can expand significantly. To form such pulses, ion beams are temporally compressed in neutralizing plasma; current amplification factors of {approx}50-100 are routinely obtained on the Neutralized Drift Compression Experiment (NDCX) at LBNL. In the NDCX-II physics design, an initial non-neutralized compression renders the pulse short enough that existing high-voltage pulsed power can be employed. This compression is first halted and then reversed by the beam's longitudinal space-charge field. Downstream induction cells provide acceleration and impose the head-to-tail velocity gradient that leads to the final neutralized compression onto the target. This paper describes the discrete-particle simulation models (1-D, 2-D, and 3-D) employed and the space-charge-dominated beam dynamics being realized.

  7. Permanent magnet electron beam ion source/trap systems with bakeable magnets for improved operation conditions

    SciTech Connect (OSTI)

    Schmidt, M., E-mail: mike.schmidt@dreebit.com [DREEBIT GmbH, 01109 Dresden (Germany); Zschornack, G.; Kentsch, U.; Ritter, E. [Department of Physics, Dresden University of Technology, 01062 Dresden, Germany and Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Ion Beam Physics and Materials Research, 01328 Dresden (Germany)] [Department of Physics, Dresden University of Technology, 01062 Dresden, Germany and Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Ion Beam Physics and Materials Research, 01328 Dresden (Germany)

    2014-02-15T23:59:59.000Z

    The magnetic system of a Dresden electron beam ion source (EBIS) generating the necessary magnetic field with a new type of permanent magnet made of high energy density NdFeB-type material operable at temperatures above 100?°C has been investigated and tested. The employment of such kind of magnets provides simplified operation without the time-consuming installation and de-installation procedures of the magnets for the necessary baking of the ion source after commissioning and maintenance work. Furthermore, with the use of a new magnetization technique the geometrical filling factor of the magnetic Dresden EBIS design could be increased to a filling factor of 100% leading to an axial magnetic field strength of approximately 0.5 T exceeding the old design by 20%. Simulations using the finite element method software Field Precision and their results compared with measurements are presented as well. It could be shown that several baking cycles at temperatures higher than 100?°C did not change the magnetic properties of the setup.

  8. Electron collisional detachment processes for a 250 keV D/sup -/ ion beam in a partially ionized hydrogen target

    SciTech Connect (OSTI)

    Savas, S.E.

    1980-09-01T23:59:59.000Z

    Neutral atom beams with energies above 200 keV may be required for various purposes in magnetic fusion devices following TFTR, JET and MFTF-B. These beams can be produced much more efficiently by electron detachment from negative ion beams than by electron capture by positive ions. We have investigated the efficiency with which such neutral atoms can be produced by electron detachment in partially ionized hydrogen plasma neutralizers.

  9. Extended-range grazing-incidence spectrometer for high-resolution extreme ultraviolet measurements on an electron beam ion trap

    SciTech Connect (OSTI)

    Beiersdorfer, P.; Magee, E. W.; Brown, G. V.; Träbert, E.; Widmann, K. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Hell, N. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Dr. Remeis-Sternwarte and ECAP, Universität Erlangen-Nürnberg, 96049 Bamberg (Germany)

    2014-11-15T23:59:59.000Z

    A high-resolution grazing-incidence grating spectrometer has been implemented on the Livermore electron beam ion traps for performing very high-resolution measurements in the soft x-ray and extreme ultraviolet region spanning from below 10 Å to above 300 Å. The instrument operates without an entrance slit and focuses the light emitted by highly charged ions located in the roughly 50 ?m wide electron beam onto a cryogenically cooled back-illuminated charge-coupled device detector. The measured line widths are below 0.025 Å above 100 Å, and the resolving power appears to be limited by the source size and Doppler broadening of the trapped ions. Comparisons with spectra obtained with existing grating spectrometers show an order of magnitude improvement in spectral resolution.

  10. Investigation of the specific plasma potential oscillations with geodesic acoustic mode frequencies by heavy ion beam probing in the T-10 tokamak

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    by heavy ion beam probing in the T-10 tokamak A V Melnikov1 , L G Eliseev1 , A V Gudozhnik1 , S E Lysenko1 of the specific oscillations with frequencies 15-30 kHz on the T-10 tokamak (R= 150cm, a = 30 cm) with Heavy IonHz) have been discovered in the tokamak by Heavy Ion Beam Probe (HIBP) diagnostic in 1993 [1, 2]. During

  11. A gas-jet transport and catcher technique for on-line production of radioactive ion beams using an electron cyclotron resonance ion-source

    SciTech Connect (OSTI)

    Naik, V.; Chakrabarti, A.; Bhattacharjee, M.; Karmakar, P.; Bandyopadhyay, A.; Dechoudhury, S.; Mondal, M.; Pandey, H. K.; Lavanyakumar, D.; Mandi, T. K.; Dutta, D. P.; Kundu Roy, T.; Bhowmick, D.; Sanyal, D.; Srivastava, S. C. L.; Ray, A.; Ali, Md. S. [Variable Energy Cyclotron Centre (VECC), Sector-1, Block-AF, Bidhan Nagar, Kolkata 700064 (India); Bhattacharjee, S. [UGC-DAE CSR, Kolkata Centre, III/LB-8, Bidhan Nagar, Kolkata 700098 (India)

    2013-03-15T23:59:59.000Z

    Radioactive ion beams (RIB) have been produced on-line, using a gas-jet recoil transport coupled Electron Cyclotron Resonance (ECR) ion-source at the VECC-RIB facility. Radioactive atoms/molecules carried through the gas-jet were stopped in a catcher placed inside the ECR plasma chamber. A skimmer has been used to remove bulk of the carrier gas at the ECR entrance. The diffusion of atoms/molecules through the catcher has been verified off-line using stable isotopes and on-line through transmission of radioactive reaction products. Beams of {sup 14}O (71 s), {sup 42}K (12.4 h), {sup 43}K (22.2 h), and {sup 41}Ar (1.8 h) have been produced by bombarding nitrogen and argon gas targets with proton and alpha particle beams from the K130 cyclotron at VECC. Typical measured intensity of RIB at the separator focal plane is found to be a few times 10{sup 3} particles per second (pps). About 3.2 Multiplication-Sign 10{sup 3} pps of 1.4 MeV {sup 14}O RIB has been measured after acceleration through a radiofrequency quadrupole linac. The details of the gas-jet coupled ECR ion-source and RIB production experiments are presented along with the plans for the future.

  12. A digitizer based compact digital spectrometer for ion beam analysis using field programmable gate arrays and various energy algorithms

    SciTech Connect (OSTI)

    Jäger, Markus [Faculty of Mathematics and Computer Science, University of Leipzig, PF 100920, 04009 Leipzig (Germany)] [Faculty of Mathematics and Computer Science, University of Leipzig, PF 100920, 04009 Leipzig (Germany); Reinert, Tilo [Department of Physics, University of North Texas, 1155 Union Circle, Denton, Texas 76203 (United States)] [Department of Physics, University of North Texas, 1155 Union Circle, Denton, Texas 76203 (United States)

    2013-08-15T23:59:59.000Z

    We report on the implementation of a compact multi-detector fully digital spectrometer and data acquisition system at a nuclear microprobe for ion beam analysis and imaging. The spectrometer design allows for system scalability with no restriction on the number of detectors. It consists of four-channel high-speed digitizer modules for detector signal acquisition and one low-speed digital-to-analog converter (DAC) module with two DAC channels and additional general purpose inputs/outputs to control ion beam scanning and data acquisition. Each digitizer module of the spectrometer provides its own Field Programmable Gate Array (FPGA) as digital signal processing unit to analyze detector signals as well as to synchronize the ion beam position in hard real-time. With the customized FPGA designs for all modules, all calculation intensive tasks are executed inside the modules, which reduces significantly the data stream to and CPU load on the control computer. To achieve an optimal energy resolution for all detector/preamplifier pulse shape characteristics, a user-definable infinite impulse response filter with high throughput for energy determination was implemented. The new spectrometer has an online data analysis feature, a compact size, and is able to process any type of detector signals such as particle induced x-ray emission, Rutherford backscattering spectrometry, or scanning transmission ion microscopy.

  13. Fundamental studies of the plasma extraction and ion beam formation processes in inductively coupled plasma mass spectrometry

    SciTech Connect (OSTI)

    Niu, Hongsen

    1995-02-10T23:59:59.000Z

    The fundamental and practical aspects are described for extracting ions from atmospheric pressure plasma sources into an analytical mass spectrometer. Methodologies and basic concepts of inductively coupled plasma mass spectrometry (ICP-MS) are emphasized in the discussion, including ion source, sampling interface, supersonic expansion, slumming process, ion optics and beam focusing, and vacuum considerations. Some new developments and innovative designs are introduced. The plasma extraction process in ICP-MS was investigated by Langmuir measurements in the region between the skimmer and first ion lens. Electron temperature (T{sub e}) is in the range 2000--11000 K and changes with probe position inside an aerosol gas flow. Electron density (n{sub e}) is in the range 10{sup 8}--10{sup 10} {sup {minus}cm }at the skimmer tip and drops abruptly to 10{sup 6}--10{sup 8} cm{sup {minus}3} near the skimmer tip and drops abruptly to 10{sup 6}--10{sup 8} cm{sup {minus}3} downstream further behind the skimmer. Electron density in the beam leaving the skimmer also depends on water loading and on the presence and mass of matrix elements. Axially resolved distributions of electron number-density and electron temperature were obtained to characterize the ion beam at a variety of plasma operating conditions. The electron density dropped by a factor of 101 along the centerline between the sampler and skimmer cones in the first stage and continued to drop by factors of 10{sup 4}--10{sup 5} downstream of skimmer to the entrance of ion lens. The electron density in the beam expansion behind sampler cone exhibited a 1/z{sup 2} intensity fall-off (z is the axial position). An second beam expansion originated from the skimmer entrance, and the beam flow underwent with another 1/z{sup 2} fall-off behind the skimmer. Skimmer interactions play an important role in plasma extraction in the ICP-MS instrument.

  14. The Relativistic Heavy Ion Collider (RHIC) cryogenic system at Brookhaven National Laboratory: Review of the modifications and upgrades since 2002 and planned improvements.

    SciTech Connect (OSTI)

    Than, R.; Tuozzolo, Joseph; Sidi-Yekhlef, Ahmed; Ganni, Venkatarao; Knudsen, Peter; Arenius, Dana

    2008-03-01T23:59:59.000Z

    Brookhaven National Laboratory continues its multi-year program to improve the operational efficiency, reliability, and stability of the cryogenic system, which also resulted in an improved beam availability of the Relativistic Heavy Ion Collider (RHIC). This paper summarizes the work and changes made after each phase over the past four years to the present, as well as proposed future improvements. Power usage dropped from an initial 9.4 MW to the present 5.1 MW and is expected to drop below 5 MW after the completion of the remaining proposed improvements. The work proceeded in phases, balancing the Collider's schedule of operation, time required for the modifications and budget constraints. The main changes include process control, compressor oil removal and management, elimination of the use of cold compressors and two liquid-helium storage tanks, insulation of the third liquid-helium storage tank, compressor-bypass flow reduction and the addition of a load turbine (Joule-Thomson ex

  15. RECENT RESULTS WITH AU IONS EXTRACTED FROM AN EBIS USING AN 8A ELECTRON BEAM AT BNL *

    E-Print Network [OSTI]

    Source (EBIS), which is a prototype for an EBIS that could meet requirements for a RHIC preinjector. RHIC INTRODUCTION At Brookhaven National Laboratory an EBIS is being developed to provide gold ions with charge state 32+ sufficient for injection into the Booster without stripping. Requirements for the intensity

  16. US Heavy Ion Beam Research for Energy Density Physics Applications and Fusion

    E-Print Network [OSTI]

    2005-01-01T23:59:59.000Z

    heavy ion inertial fusion energy. ACKNOWLEDGEMENTS Thisheavy ion inertial fusion energy. These include: neutralizedto drift axially). For fusion energy applications, either

  17. Recent U.S. advances in ion-beam-driven high energy density physics and heavy ion fusion

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    physics and heavy ion fusion energy drivers, including bothoptions towards inertial fusion energy. Acknowledgements:fusion drivers for inertial fusion energy. 1. Introduction A

  18. Laboratory robotics -- An automated tool for preparing ion chromatography calibration standards

    SciTech Connect (OSTI)

    Chadwick, J.L.

    1995-04-01T23:59:59.000Z

    This paper describes the use of a laboratory robot as an automated tool for preparing multi-level calibration standards for On-Line Ion Chromatography (IC) Systems. The robot is designed for preparation of up to six levels of standards, with each level containing up to eleven ionic species in aqueous solution. The robot is required to add the standards` constituents as both a liquid and solid additions and to keep a record of exactly what goes into making up every standard. Utilizing a laboratory robot to prepare calibration standards provides significant benefits to the testing environment. These benefits include: accurate and precise calibration standards in individually capped containers with preparation traceability; automated and unattended multi-specie preparation for both anion and cation analytical channels; the ability to free up a test operator from a repetitive routine and re-apply those efforts to test operations; The robot uses a single channel IC to analyze each prepared standard for specie content and concentration. Those results are later used as a measure of quality control. System requirements and configurations, robotic operations, manpower requirements, analytical verification, accuracy and precision of prepared solutions, and robotic downtime are discussed in detail.

  19. Cross-sectional TEM Observations of Si Wafers Irradiated With Gas Cluster Ion Beams

    SciTech Connect (OSTI)

    Isogai, Hiromichi; Toyoda, Eiji; Senda, Takeshi; Izunome, Koji [Processing Technology, Silicon Business Group, TOSHIBA CERAMICS CO., LTD. 6-861-5 Higashikou, Seiroumachi Kitakanbaragun, Niigata (Japan); Kashima, Kazuhiko [New Buisness Creation, TOSHIBA CERAMICS CO., LTD. 30 Soya, Hadano City, Kanagawa (Japan); Toyoda, Noriaki; Yamada, Isao [Laboratory of Advanced Science and Technology for Industry, University of Hyogo, 3-1-2 Kouto, Kamigori, Hyogo (Japan)

    2006-11-13T23:59:59.000Z

    Irradiation by a Gas Cluster Ion Beam (GCIB) is a promising technique for precise surface etching and planarization of Si wafers. However, it is very important to understand the crystalline structure of Si wafers after GCIB irradiation. In this study, the near surface structure of a Si (100) wafer was analyzed after GCIB irradiation, using a cross-sectional transmission electron microscope (XTEM). Ar-GCIB, that physically sputters Si atoms, and SF6-GCIB, that chemically etches the Si surface, were both used. After GCIB irradiation, high temperature annealing was performed in a hydrogen atmosphere. From XTEM observations, the surface of a virgin Si wafer exhibited completely crystalline structures, but the existence of an amorphous Si and a transition layer was confirmed after GCIB irradiation. The thickness of amorphous layer was about 30 nm after Ar-GCIB irradiation at 30 keV. However, a very thin (< 5 nm) layer was observed when 30 keV SF6-GCIB was used. The thickness of the transition layer was the same both Ar and SF6-GCIB irradiation. After annealing, the amorphous Si and transition layers had disappeared, and a complete crystalline structure with an atomically smooth surface was observed.

  20. Control system for 5 MW neutral beam ion source for SST1

    SciTech Connect (OSTI)

    Patel, G.B.; Onali, Raja; Sharma, Vivek; Suresh, S.; Tripathi, V.; Bandyopadhyay, M.; Singh, N.P.; Thakkar, Dipal; Gupta, L.N.; Singh, M.J.; Patel, P.J.; Chakraborty, A.K.; Baruah, U.K.; Mattoo, S.K. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat, India-382428 (India)

    2006-01-15T23:59:59.000Z

    This article describes the control system for a 5 MW ion source of the NBI (neutral beam injector) for steady-state superconducting tokamak-1 (SST-1). The system uses both hardware and software solutions. It comprises a DAS (data acquisition system) and a control system. The DAS is used to read the voltage and current signals from eight filament heater power supplies and 24 discharge power supplies. The control system is used to adjust the filament heater current in order to achieve an effective control on the discharge current in the plasma box. The system consists of a VME (Verse Module Eurocard) system and C application program running on a VxWorks{sup TM} real-time operating system. A PID (proportional, integral, and differential) algorithm is used to control the filament heater current. Experiments using this system have shown that the discharge current can be controlled within 1% accuracy for a PID loop time of 20 ms. Response of the control system to the pressure variation of the gas in the chamber has also been studied and compared with the results obtained from those of an uncontrolled system. The present approach increases the flexibility of the control system. It not only eases the control of the plasma but also allows an easy changeover to various operation scenarios.

  1. Structural and composition investigations at delayered locations of low k integrated circuit device by gas-assisted focused ion beam

    SciTech Connect (OSTI)

    Wang, Dandan, E-mail: dandan.wang@globalfoundries.com; Kee Tan, Pik; Yamin Huang, Maggie; Lam, Jeffrey; Mai, Zhihong [Technology Development Department, GLOBALFOUNDRIES Singapore Pte. Ltd., 60 Woodlands Industrial Park D, Street 2, Singapore 738406 (Singapore)

    2014-05-15T23:59:59.000Z

    The authors report a new delayering technique – gas-assisted focused ion beam (FIB) method and its effects on the top layer materials of integrated circuit (IC) device. It demonstrates a highly efficient failure analysis with investigations on the precise location. After removing the dielectric layers under the bombardment of an ion beam, the chemical composition of the top layer was altered with the reduced oxygen content. Further energy-dispersive x-ray spectroscopy and Fourier transform infrared analysis revealed that the oxygen reduction lead to appreciable silicon suboxide formation. Our findings with structural and composition alteration of dielectric layer after FIB delayering open up a new insight avenue for the failure analysis in IC devices.

  2. MEASUREMENT OF ION BEAM FROM LASER ION SOURCE FOR RHIC Takeshi Kanesue, Kyushu University, Fukuoka 819-0395, Japan

    E-Print Network [OSTI]

    , vaporized and becomes plasma which is called laser ablation plasma then plasma expand adiabatically perpendicular to the target surface. Properties of Laser ablation plasma such as charge state distribution, and emittance of Au ions extracted from laser ablation plasma was measured. SINGLY CHARGED ION PRODUCTION We

  3. Submicro and Nano Structured Porous Materials for the Production of High-Intensity Exotic Radioactive Ion Beams

    E-Print Network [OSTI]

    Fernandes, Sandrina; Stora, Thierry

    2010-01-01T23:59:59.000Z

    ISOLDE, the CERN Isotope Separator On-line DEvice is a unique source of low energy beams of radioactive isotopes - atomic nuclei that have too many or too few neutrons to be stable. The facility is like a small ‘chemical factory’, giving the possibility of changing one element to another, by selecting the atomic mass of the required isotope beam in the mass separator, rather as the ‘alchemists’ once imagined. It produces a total of more than 1000 different isotopes from helium to radium, with half-lives down to milliseconds, by impinging a 1.4 GeV proton beam from the Proton Synchrotron Booster (PSB) onto special targets, yielding a wide variety of atomic fragments. Different components then extract the nuclei and separate them according to mass. The post-accelerator REX (Radioactive beam EXperiment) at ISOLDE accelerates the radioactive beams up to 3 MeV/u for many experiments. A wide international user radioactive ion beam (RIB) community investigates fundamental aspects of nuclear physics, particle...

  4. Glass nanoimprint using amorphous Ni-P mold etched by focused-ion beam

    SciTech Connect (OSTI)

    Mekaru, Harutaka; Kitadani, Takeshi; Yamashita, Michiru; Takahashi, Masaharu [National Institute of Advanced Industrial Science and Technology (AIST), 1-2-1, Namiki, Tsukuba, Ibaraki 305-8564 (Japan); SAWA Plating Co., Ltd., 753 Hoshiro, Himeji, Hyogo 670-0804 (Japan); Hyogo Prefectural Institute of Technology, 3-1-12 Yukihira-cho, Suma-ku, Kobe 654-0037 (Japan); National Institute of Advanced Industrial Science and Technology (AIST), 1-2-1 Namiki, Tsukuba, Ibaraki 305-8564 (Japan)

    2007-07-15T23:59:59.000Z

    The authors succeeded in glass-nanoimprint lithography of micropatterns and nanopatterns using an amorphous Ni-P alloy mold. Glasslike carbon has been used as a mold material to mold not only Pyrex glass but also quartz, because it is still stable at a temperature of 1650 deg. C. However, it is difficult to process glasslike carbon substrates into arbitrary shapes by machining. They thought that amorphous Ni-P alloy could be used as a mold material for industrial glass molding. If Ni is electroless plated when mixed with suitable amount of P on a Si wafer, the Ni-P alloy layer becomes amorphous. An appropriate ratio of Ni and P was determined by the results of x-ray-diffraction measurements. The optimized composition ratio of Ni-P was Ni:P=92:8 wt %. Moreover, line and space patterns and dot arrays with linewidths of as little as 500 nm were etched on the mold using focused-ion beam (FIB) and the processing accuracy for the amorphous Ni-P layer was compared with that for the pure Ni layer. The result was that patterns of 500 nm width were etched to a depth of 2 {mu}m on an amorphous Ni-P alloy mold and the processed surfaces were smooth. In contrast, in the case of the pure Ni layer, the processing line was notched and the sidewalls were very rough. The crystal grain seems to hinder the processing of the nanopattern. After FIB etching, the amorphous Ni-P alloy was thermally treated at 400 deg. C to improve the hardness. Finally, line and space patterns and dot arrays on the amorphous Ni-P alloy mold were nanoimprinted on Pyrex glass using a glass-nanoimprint system (ASHE0201) that National Institute of Advanced Industrial Science and Technology developed.

  5. A PARALLEL-PROPAGATING ALFVENIC ION-BEAM INSTABILITY IN THE HIGH-BETA SOLAR WIND

    SciTech Connect (OSTI)

    Verscharen, Daniel; Bourouaine, Sofiane; Chandran, Benjamin D. G. [Space Science Center, University of New Hampshire, Durham, NH 03824 (United States); Maruca, Bennett A., E-mail: daniel.verscharen@unh.edu, E-mail: s.bourouaine@unh.edu, E-mail: benjamin.chandran@unh.edu, E-mail: bmaruca@ssl.berkeley.edu [Space Science Laboratory, University of California, Berkeley, CA 94720 (United States)

    2013-08-10T23:59:59.000Z

    We investigate the conditions under which parallel-propagating Alfven/ion-cyclotron waves are driven unstable by an isotropic (T{sub {alpha}} = T{sub Parallel-To {alpha}}) population of alpha particles drifting parallel to the magnetic field at an average speed U{sub {alpha}} with respect to the protons. We derive an approximate analytic condition for the minimum value of U{sub {alpha}} needed to excite this instability and refine this result using numerical solutions to the hot-plasma dispersion relation. When the alpha-particle number density is {approx_equal} 5% of the proton number density and the two species have similar thermal speeds, the instability requires that {beta}{sub p} {approx}> 1, where {beta}{sub p} is the ratio of the proton pressure to the magnetic pressure. For 1 {approx}< {beta}{sub p} {approx}< 12, the minimum U{sub {alpha}} needed to excite this instability ranges from 0.7v{sub A} to 0.9v{sub A}, where v{sub A} is the Alfven speed. This threshold is smaller than the threshold of {approx_equal} 1.2v{sub A} for the parallel magnetosonic instability, which was previously thought to have the lowest threshold of the alpha-particle beam instabilities at {beta}{sub p} {approx}> 0.5. We discuss the role of the parallel Alfvenic drift instability for the evolution of the alpha-particle drift speed in the solar wind. We also analyze measurements from the Wind spacecraft's Faraday cups and show that the U{sub {alpha}} values measured in solar-wind streams with T{sub {alpha}} Almost-Equal-To T{sub Parallel-To {alpha}} are approximately bounded from above by the threshold of the parallel Alfvenic instability.

  6. Understanding extraction and beam transport in the ISIS H{sup -} Penning surface plasma ion source

    SciTech Connect (OSTI)

    Faircloth, D. C.; Letchford, A. P.; Gabor, C.; Whitehead, M. O.; Wood, T.; Jolly, S.; Pozimski, J.; Savage, P.; Woods, M. [STFC/RAL, Chilton, Didcot, Oxon OX11 0QX (United Kingdom); Imperial College, London SW7 2AZ (United Kingdom)

    2008-02-15T23:59:59.000Z

    The ISIS H{sup -} Penning surface plasma source has been developed to produce beam currents up to 70 mA and pulse lengths up to 1.5 ms at 50 Hz. This paper details the investigation into beam extraction and beam transport in an attempt to understand the beam emittance and to try to improve the emittance. A scintillator profile measurement technique has been developed to assess the performance of different plasma electrode apertures, extraction electrode geometries, and postextraction acceleration configurations. This work shows that the present extraction, beam transport, and postacceleration system are suboptimal and further work is required to improve it.

  7. The Heavy Ion Fusion Virtual National Laboratory Status and new physics directions for heavy-ion-driven

    E-Print Network [OSTI]

    Numbers DE-AC03-76SF00098 and W-7405-Eng-48, and by the Princeton Plasma Physics Laboratory under Contract

  8. Dependence of ion beam current on position of mobile plate tuner in multi-frequencies microwaves electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Kurisu, Yosuke; Kiriyama, Ryutaro; Takenaka, Tomoya; Nozaki, Dai; Sato, Fuminobu; Kato, Yushi; Iida, Toshiyuki [Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2012-02-15T23:59:59.000Z

    We are constructing a tandem-type electron cyclotron resonance ion source (ECRIS). The first stage of this can supply 2.45 GHz and 11-13 GHz microwaves to plasma chamber individually and simultaneously. We optimize the beam current I{sub FC} by the mobile plate tuner. The I{sub FC} is affected by the position of the mobile plate tuner in the chamber as like a circular cavity resonator. We aim to clarify the relation between the I{sub FC} and the ion saturation current in the ECRIS against the position of the mobile plate tuner. We obtained the result that the variation of the plasma density contributes largely to the variation of the I{sub FC} when we change the position of the mobile plate tuner.

  9. Time evolution of the luminosity of colliding heavy-ion beams in BNL Relativistic Heavy Ion Collider and CERN Large Hadron Collider

    E-Print Network [OSTI]

    Bruce, R; Fischer, W; Jowett, J M

    2010-01-01T23:59:59.000Z

    We have studied the time evolution of the heavy ion luminosity and bunch intensities in the Relativistic Heavy Ion Collider (RHIC), at BNL, and in the Large Hadron Collider (LHC), at CERN. First, we present measurements from a large number of RHIC stores (from Run 7), colliding 100 GeV/nucleon 197Au79+ beams without stochastic cooling. These are compared with two different calculation methods. The first is a simulation based on multi-particle tracking taking into account collisions, intrabeam scattering, radiation damping, and synchrotron and betatron motion. In the second, faster, method, a system of ordinary differential equations with terms describing the corresponding effects on emittances and bunch populations is solved numerically. Results of the tracking method agree very well with the RHIC data. With the faster method, significant discrepancies are found since the losses of particles diffusing out of the RF bucket due to intrabeam scattering are not modeled accurately enough. Finally, we use both meth...

  10. Beam-ion confinement for different injection geometries This article has been downloaded from IOPscience. Please scroll down to see the full text article.

    E-Print Network [OSTI]

    Heidbrink, William W.

    energy, torque and particles, so a thorough understanding of beam behavior is crucial for plasma of contents for this issue, or go to the journal homepage for more Home Search Collections Journals About-ion energy and at high plasma temperature, suggesting that fast-ion transport by microturbulence

  11. Sub-50 nm high aspect-ratio silicon pillars, ridges, and trenches fabricated using ultrahigh resolution electron beam lithography and reactive ion

    E-Print Network [OSTI]

    resolution electron beam lithography and reactive ion etching P. B. Fischer and S. Y. Chou University of Minnesota Department of Electrical Engineering, Minneapolis, Minnesota 554~3 (Received 29 July 1992 and chlorine based reactive ion etching. These nanoscale Si features can be further reduced to 10 nm using

  12. Measurement and simulation of the impact of coherent synchrotron radiation on the Jefferson Laboratory energy recovery linac electron beam

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hall, C C.; Biedron, S G.; Edelen, A L.; Milton, S V.; Benson, S; Douglas, D; Li, R; Tennant, C D.; Carlsten, B E.

    2015-03-01T23:59:59.000Z

    In an experiment conducted on the Jefferson Laboratory IR free-electron laser driver, the effects of coherent synchrotron radiation (CSR) on beam quality were studied. The primary goal of this work was to explore CSR output and effect on the beam with variation of the bunch compression in the IR recirculator. Here we examine the impact of CSR on the average energy loss as a function of bunch compression as well as the impact of CSR on the energy spectrum of the bunch. Simulation of beam dynamics in the machine, including the one-dimensional CSR model, shows very good agreement with themore »measured effect of CSR on the average energy loss as a function of compression. Finally, a well-defined structure is observed in the energy spectrum with a feature in the spectrum that varies as a function of the compression. This effect is examined in simulations, as well, and a simple explanation for the variation is proposed.« less

  13. Time evolution of the luminosity of colliding heavy-ion beams in BNL Relativistic Heavy Ion Collider and CERN Large Hadron Collider

    E-Print Network [OSTI]

    R. Bruce; M. Blaskiewicz; W. Fischer; J. M. Jowett

    2010-09-08T23:59:59.000Z

    We have studied the time evolution of the heavy ion luminosity and bunch intensities in the Relativistic Heavy Ion Collider (RHIC), at BNL, and in the Large Hadron Collider (LHC), at CERN. First, we present measurements from a large number of RHIC stores (from Run 7), colliding 100 GeV/nucleon Au beams without stochastic cooling. These are compared with two different calculation methods. The first is a simulation based on multi-particle tracking taking into account collisions, intrabeam scattering, radiation damping, and synchrotron and betatron motion. In the second, faster, method, a system of ordinary differential equations with terms describing the corresponding effects on emittances and bunch populations is solved numerically. Results of the tracking method agree very well with the RHIC data. With the faster method, significant discrepancies are found since the losses of particles diffusing out of the RF bucket due to intrabeam scattering are not modeled accurately enough. Finally, we use both methods to make predictions of the time evolution of the future Pb beams in the LHC at injection and collision energy. For this machine, the two methods agree well.

  14. NEGATIVE ION PRODUCTION BY BACK-SCATTERING FROM ALKALI-METAL SURFACES BOMBARDED BY IONS OF HYDROGEN AND DEUTERIUM.

    E-Print Network [OSTI]

    Schneider, Peter Juergen

    2010-01-01T23:59:59.000Z

    and Neutralization of Negative Hydrogen Ions and Beams (and Neutralization of Negative Hydrogen Ions and Beams (and Neutralization of Negative Hydrogen Ions and Beams,

  15. Beam Energy Scaling on Ion-Induced Electron Yield from K+ Impact on Stainless Steel

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    K + Impact on Stainless Steel Michel Kireeff Covo Lawrence+ ions hit the stainless steel target with energy up to 400energies hitting stainless steel target obtained from

  16. Towards an electro-magnetic field separation of deposited material implemented in an ion beam sputter process

    SciTech Connect (OSTI)

    Malobabic, Sina; Jupe, Marco; Ristau, Detlev [Laser Component Department, Laser Zentrum Hannover e.V., Hollerithallee 8, 30149 Hannover (Germany) [Laser Component Department, Laser Zentrum Hannover e.V., Hollerithallee 8, 30149 Hannover (Germany); Quest: Centre of Quantum Engineering and Space-Time Research, Leibniz Universitaet Hannover, Hannover (Germany)

    2013-06-03T23:59:59.000Z

    Nowadays, Ion Beam Sputter (IBS) processes are very well optimized on an empirical basis. To achieve further progresses, a modification of the IBS process by guiding the coating material using an axial magnetic field and an additional electrical field has been studied. The electro-magnetic (EM) field leads to a significant change in plasma properties and deposition rate distributions, whereas an increase in deposition rate along the centerline of the axial EM field around 150% was observed. These fundamental studies on the prototype are the basis for the development of an applicable and workable design of a separation device.

  17. Spectra of In-like Tungsten, $W^{25+}$, from the Shanghai permanent magnet electron beam ion trap

    E-Print Network [OSTI]

    Li, W; Shi, Z; Fei, Z; R,; Zhao,; Brage, T; Huldt, S; Hutton, R; Zou, Y

    2015-01-01T23:59:59.000Z

    Three visible lines of M1 transitions from In-like W were recorded using the Shanghai permanent magnet electron beam ion trap. The experimental wavelengths were measured as 493.84 $\\pm$ 0.15, 226.97 $\\pm$ 0.13 and 587.63 $\\pm$ 0.23 nm (vacuum wavelengths). These results are in good agreement with theoretical predictions obtained using large-scale Relativistic Many-Body Perturbation Theory, in the form of the Flexible Atomic Code, and some explorations with the Muliconfiguration Dirac-Hartree-Fock code GRASP2K.

  18. Fast six-channel pyrometer for warm-dense-matter experiments with intense heavy-ion beams

    SciTech Connect (OSTI)

    Ni, P.A.; Kulish, M.I.; Mintsev, V.; Nikolaev, D.N.; Ternovoi, V.Ya.; Hoffmann, D.H.H.; Udrea, S.; Tahir, N.A.; Varentsov, D.; Hug, A.

    2008-12-01T23:59:59.000Z

    This paper describes a fast multi-channel radiation pyrometer that was developed for warmdense-matter experiments with intense heavy ion beams at Gesellschaft fur Schwerionenforschung mbH (GSI). The pyrometer is capable of measuring of brightness temperatures from 2000 K to 50000 K, at 6 wavelengths in visible and near-infrared parts of spectrum, with 5 nanosecond temporal resolution and several micrometers spatial resolution. The pyrometer's spectral discrimination technique is based on interference filters, which act as filters and mirrors to allow for simultaneous spectral discrimination of the same ray at multiple wavelengths.

  19. Confined Thermal Multicharged Ions Produced by Synchrotron Radiation

    E-Print Network [OSTI]

    Church, David A.; Kravis, S. D.; Sellin, I. A.; Levin, J. C.; Short, R. T.; Meron, M.; Johnson, B. M.; Jones, K. W.

    1987-01-01T23:59:59.000Z

    energy transfer. We have used the "white" radiation on the X- 26C beam line of the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory to generate multicharged argon ions in a Penning ion trap, using pro- posed methods designed... M. Meron, B. M. Johnson, and K. W. Jones Brookhaven National Laboratory, Upton, New York 11973 (Received 2 April 1987) Synchrotron x rays have been used to produce a confined multicharged ion gas near room tem- perature. Comparison of charge...

  20. NEUTRALIZED TRANSPORT OF HIGH INTENSITY BEAMS E. Henestroza #

    E-Print Network [OSTI]

    Gilson, Erik

    for specific degrees of neutralization. PLASMA NEUTRALIZATION Neutralization is essential for focusing heavy (~ 10-3 Torr). Final focus magnet Target Volumetric plasma Converging ion beam Chamber Wall at the Heavy Ion Fusion Virtual National Laboratory is exploring the performance of neutralized final focus

  1. Neutralization of space charge on high-current low-energy ion beam by low-energy electrons supplied from silicon based field emitter arrays

    SciTech Connect (OSTI)

    Gotoh, Yasuhito; Tsuji, Hiroshi; Taguchi, Shuhei; Ikeda, Keita; Kitagawa, Takayuki; Ishikawa, Junzo; Sakai, Shigeki [Dept. of Electron. Sci. Eng., Kyoto Univ. Kyotodaigaku-Katsura, Nishikyo-ku, Kyoto 615-8510 (Japan); Dept. of Electron. Information Eng., Chubu Univ., 1200, Matsumoto-cho, Kasugai, Aichi 487-8501 (Japan); Nissin Ion Equipment Co., Ltd., 575 Kuze-Tonoshiro-cho, Minami-ku, Kyoto 601-8502 (Japan)

    2012-11-06T23:59:59.000Z

    Neutralization of space charge on a high-current and low-energy ion beam was attempted to reduce the divergence with an aid of low-energy electrons supplied from silicon based field emitter arrays (Si-FEAs). An argon ion beam with the energy of 500 eV and the current of 0.25 mA was produced by a microwave ion source. The initial beam divergence and the emittance were measured at the entrance of the analysis chamber in order to estimate the intrinsic factors for beam divergence. The current density distribution of the beam after transport of 730 mm was measured by a movable Faraday cup, with and without electron supply from Si-FEAs. A similar experiment was performed with tungsten filaments as an electron source. The results indicated that the electron supply from FEA had almost the same effect as the thermionic filament, and it was confirmed that both electron sources can neutralize the ion beam.

  2. ION BEAM HEATED TARGET SIMULATIONS FOR WARM DENSE MATTER PHYSICS AND INERTIAL FUSION ENERGY

    E-Print Network [OSTI]

    Barnard, J.J.

    2008-01-01T23:59:59.000Z

    PHYSICS AND INERTIAL FUSION ENERGY J. J. Barnard 1 , J.dense matter and inertial fusion energy related beam-targetas drivers for inertial fusion energy (IFE), for their high

  3. Energy Amplification and Beam Bunching in a Pulse Line Ion Accelerator

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    ST Accel. Beams 7, [7] P. K. Roy et al. , Phys. of Plasmas12, 043102 (2005). [10] P. K. Roy et al. , Nucl. Instrum.Phy. Res. A 544, [11] P. K. Roy et al. , Phys. Rev. Lett.

  4. Direct Drive Heavy-Ion-Beam Inertial Fusion at High Coupling Efficiency

    E-Print Network [OSTI]

    Logan, B. Grant

    2008-01-01T23:59:59.000Z

    Fusion at High Coupling Efficiency B.G. Logan 1, L.J.fusion at high coupling efficiency B. G. Logan , L . J.Issues with coupling efficiency, beam illumination symmetry

  5. SU-D-BRE-04: Evaluating the Dose Accuracy of a 2D Ion Chamber Array in High Dose Rate Pencil Beam Scanning Proton Beam

    SciTech Connect (OSTI)

    Perles, L; Mascia, A; Piskulich, F; Lepage, R; Zhang, Y; Giebeler, A; Dong, L [Scripps Proton Therapy Center, San Diego, CA (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To evaluate the absolute dose accuracy of the PTW Octavius 729 XDR 2D ion chamber array at a high dose rate pencil beam scanning proton therapy facility. Methods: A set of 18 plans were created in our treatment planning system, each of which comprising a unique combination of field sizes (FS), length of spread out of Bragg peaks (SOBP) and depths. The parameters used were: FS of 5×5cm{sup 2}, 10×10cm{sup 2} and 15×15cm{sup 2}; flat SOBP of 5cm and 10cm; and isocenter depths of 10cm, 15cm and 20cm, which coincides with the center of the SOBP. The 2D array detector was positioned at the machine isocenter and the appropriate amount of solid water was used to match the planned depths of 10, 15 and 20 cm water equivalent depth. Subsequently, we measured the absolute dose at isocenter using a CC04 ion chamber in a 1D water tank. Both 2D array and CC04 were previously cross calibrated. We also collected the MU rates used by our proton machine from the log files. Results: The relative differences between the CC04 and the 2D array can be summarized into two groups, one with 5 cm SOBP and another with 10 cm SOBP. Plotting these datasets against FS shows that the 2D array response for high dose rate fields (FS of 5×5cm{sup 2} and 5cm SOBP) can be up to 2% lower. Similarly, plotting them against isocenter depths reveals the detector's response can be up to 2% lower for higher energy beams (about 200MeV nominal). The MU rate found in the machine log files for 5cm SOBP's were as high as twice the MU rate for the 10cm SOBP. Conclusion: The 2D array dose response showed a dose rate effect in scanning pencil beam delivery, which needs to be corrected to achieve a better dose accuracy.

  6. The use of multi-gap resistive plate chambers for in-beam PET in proton and carbon ion therapy

    E-Print Network [OSTI]

    Watts, David; Sauli, Fabio; Amaldi, Ugo

    2013-01-01T23:59:59.000Z

    On-line verification of the delivered dose during proton and carbon ion radiotherapy is currently a very desirable goal for quality assurance of hadron therapy treatment plans. In-beam positron emission tomography (ibPET), which can provide an image of the ?+ activity induced in the patient during irradiation, which in turn is correlated to the range of the ion beam, is one of the modalities for achieving this goal. Application to hadron therapy requires that the scanner geometry be modified from that which is used in nuclear medicine. In particular, PET detectors that allow a sub-nanosecond time-of-flight (TOF) registration of the collinear photons have been proposed. Inclusion of the TOF information in PET data leads to more effective PET sensitivity. Considering the challenges inherent in the ibPET technique, namely limited ?+ activity and the effect of biological washout due to blood flow, TOF-PET technologies are very attractive. In this context, the TERA Foundation is investigating the use of resistiv...

  7. Polyvinyltoluene scintillators for relative ion dosimetry: an investigation with Helium, Carbon and Neon beams.

    E-Print Network [OSTI]

    Boyer, Edmond

    facility (Heavy Ion Medical Accelerator in Chiba) of the NIRS (National Institute of Radiological Sciences Pasteur, 23 rue du Loess, 67037 Strasbourg, France. b National Institute of Radiological Sciences, 4

  8. MONO1001 : A source for singly charged ions applied to the production of multicharged fullerene beams

    E-Print Network [OSTI]

    Boyer, Edmond

    (from pure C60 and C70 powder) will be shown and the influence of several source parameters (HF-power, support gas, gas pressure, ...) will be discussed specifying the conditions necessary for an optimum ion

  9. U.S. Heavy Ion Beam Science towards inertial fusion energy

    E-Print Network [OSTI]

    2002-01-01T23:59:59.000Z

    Science towards Inertial Fusion Energy B.G. Logan 1), D.activities for inertial fusion energy at Lawrence LivermoreIon Fusion in the U.S. Fusion Energy Sciences Program [25].

  10. Self-pinched beam transport experiments Relevant to Heavy Ion Driven inertial fusion energy

    E-Print Network [OSTI]

    1998-01-01T23:59:59.000Z

    C. L . Olson, J. Fusion Energy 1, 309 (1982). "FilamentationHeavy Ion Driven Inertial Fusion Energy January 30, 1998 W.Agency Sixteenth I A E A Fusion Energy Conference (Montreal,

  11. Offline trapping of $^{221}$Fr in a magneto-optical trap from implantation of an $^{225}$Ac ion beam

    E-Print Network [OSTI]

    M. Tandecki; J. Zhang; S. Aubin; J. A. Behr; R. Collister; E. Gomez; G. Gwinner; H. Heggen; J. Lassen; L. A. Orozco; M. R. Pearson; S. Raeder; A. Teigelhöfer

    2014-09-30T23:59:59.000Z

    We demonstrate a new technique to prepare an offline source of francium for trapping in a magneto-optical trap. Implanting a radioactive beam of $^{225}$Ac, $t_{1/2} = 9.920(3)$ days, in a foil, allows use of the decay products, i.e.$^{221}$Fr, $t_{1/2} = 288.0(4)$ s. $^{221}$Fr is ejected from the foil by the $\\alpha$ decay of $^{225}$Ac. This technique is compatible with the online accumulation of a laser-cooled atomic francium sample for a series of planned parity non-conservation measurements at TRIUMF. We obtain a 34% release efficiency for $^{221}$Fr from the recoil source based on particle detector measurements. We find that laser cooling operation with the source is $8^{+10}_{-5}$ times less efficient than from a mass-separated ion beam of $^{221}$Fr in the current geometry. While the flux of this source is two to three orders of magnitude lower than typical francium beams from ISOL facilities, the source provides a longer-term supply of francium for offline studies.

  12. Effect of low energy oxygen ion beam irradiation on ionic conductivity of solid polymer electrolyte

    SciTech Connect (OSTI)

    Manjunatha, H., E-mail: gnk-swamy@blr.amrita.edu; Kumaraswamy, G. N., E-mail: gnk-swamy@blr.amrita.edu [Department of Physics, Amrita Vishwa Vidyapeetham, Bengaluru-560035 (India); Damle, R. [Department of Physics, Bangalore University, Bengaluru-560056 (India)

    2014-04-24T23:59:59.000Z

    Over the past three decades, solid polymer electrolytes (SPEs) have drawn significant attention of researchers due to their prospective commercial applications in high energy-density batteries, electrochemical sensors and super-capacitors. The optimum conductivity required for such applications is about 10{sup ?2} – 10{sup ?4} S/cm, which is hard to achieve in these systems. It is known that the increase in the concentration of salt in the host polymer results in a continuous increase in the ionic conductivity. However, there is a critical concentration of the salt beyond which the conductivity decreases due to formation of ion pairs with no net charge. In the present study, an attempt is made to identify the concentration at which ion pair formation occurs in PEO: RbBr. We have attempted to modify microstructure of the host polymer matrix by low energy ion (Oxygen ion, O{sup +1} with energy 100 keV) irradiation. Ionic conductivity measurements in these systems were carried out using Impedance Spectroscopy before and after irradiation to different fluencies of the oxygen ion. It is observed that the conductivity increases by one order in magnitude. The increase in ionic conductivity may be attributed to the enhanced segmental motion of the polymer chains. The study reveals the importance of ion irradiation as an effective tool to enhance conductivity in SPEs.

  13. Bulk ion acceleration and particle heating during magnetic reconnection in a laboratory plasma

    SciTech Connect (OSTI)

    Yoo, Jongsoo; Yamada, Masaaki; Ji, Hantao; Jara-Almonte, Jonathan; Myers, Clayton E. [Center for Magnetic Self-Organization, Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)] [Center for Magnetic Self-Organization, Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

    2014-05-15T23:59:59.000Z

    Bulk ion acceleration and particle heating during magnetic reconnection are studied in the collisionless plasma of the Magnetic Reconnection Experiment (MRX). The plasma is in the two-fluid regime, where the motion of the ions is decoupled from that of the electrons within the ion diffusion region. The reconnection process studied here is quasi-symmetric since plasma parameters such as the magnitude of the reconnecting magnetic field, the plasma density, and temperature are compatible on each side of the current sheet. Our experimental data show that the in-plane (Hall) electric field plays a key role in ion heating and acceleration. The electrostatic potential that produces the in-plane electric field is established by electrons that are accelerated near the electron diffusion region. The in-plane profile of this electrostatic potential shows a “well” structure along the direction normal to the reconnection current sheet. This well becomes deeper and wider downstream as its boundary expands along the separatrices where the in-plane electric field is strongest. Since the in-plane electric field is 3–4 times larger than the out-of-plane reconnection electric field, it is the primary source of energy for the unmagnetized ions. With regard to ion acceleration, the Hall electric field causes ions near separatrices to be ballistically accelerated toward the outflow direction. Ion heating occurs as the accelerated ions travel into the high pressure downstream region. This downstream ion heating cannot be explained by classical, unmagnetized transport theory; instead, we conclude that ions are heated by re-magnetization of ions in the reconnection exhaust and collisions. Two-dimensional (2-D) simulations with the global geometry similar to MRX demonstrate downstream ion thermalization by the above mechanisms. Electrons are also significantly heated during reconnection. The electron temperature sharply increases across the separatrices and peaks just outside of the electron diffusion region. Unlike ions, electrons acquire energy mostly from the reconnection electric field, and the energy gain is localized near the X-point. However, the increase in the electron bulk flow energy remains negligible. These observations support the assertion that efficient electron heating mechanisms exist around the electron diffusion region and that the heat generated there is quickly transported along the magnetic field due to the high parallel thermal conductivity of electrons. Classical Ohmic dissipation based on the perpendicular Spitzer resistivity is too small to balance the measured heat flux, indicating the presence of anomalous electron heating.

  14. Beta-dependent upper bound on ion temperature anisotropy in a laboratory plasma

    SciTech Connect (OSTI)

    Keiter, Paul A. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Scime, Earl E. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Balkey, Matthew M. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Boivin, Robert [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Kline, John L. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Gary, S. Peter [Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)

    2000-03-01T23:59:59.000Z

    Laser induced fluorescence measurements of ion temperatures, parallel and perpendicular to the local magnetic field, in the Large Experiment on Instabilities and Anisotropies space simulation chamber (a steady-state, high beta, argon plasma) display an inverse correlation between the upper bound on the ion temperature anisotropy and the parallel ion beta ({beta}=8{pi}nkT/B{sup 2}). These observations are consistent with in situ spacecraft measurements in the Earth's magnetosheath and with a theoretical/computational model that predicts that such an upper bound is imposed by scattering from enhanced fluctuations due to growth of the ion cyclotron anisotropy instability (the Alfven ion cyclotron instability). (c) 2000 American Institute of Physics.

  15. Isospin Effects in Heavy-Ion Collisions: Some Results From CHIMERA Experiments At LNS And Perspectives With Radioactive Beams

    SciTech Connect (OSTI)

    Cardella, G.; De Filippo, E.; Pagano, A.; Papa, M.; Pirrone, S.; Verde, G. [INFN, Sez di Catania, Via S. Sofia 64-95123 Catania (Italy); Amorini, F.; Cavallaro, S.; Lombardo, I.; Porto, F.; Rizzo, F.; Russotto, P. [INFN Lab. Naz. del Sud, Via S. Sofia 44-95123 Catania (Italy); Dep. of Phys. and Astr. Univ. Catania Via S. Sofia 64-95123 Catania (Italy); Anzalone, A.; Maiolino, C. [INFN Lab. Naz. del Sud, Via S. Sofia 44-95123 Catania (Italy); Arena, N.; Geraci, E.; Grassi, L.; Lo Nigro, S.; Politi, G. [INFN, Sez di Catania, Via S. Sofia 64-95123 Catania (Italy); Dep. of Phys. and Astr. Univ. Catania Via S. Sofia 64-95123 Catania (Italy); Auditore, L. [INFN and Dep. of Phys. Univ. Messina (Italy)] (and others)

    2009-05-04T23:59:59.000Z

    CHIMERA is a 4{pi} multidetector for charged particles available at Laboratori Nazionali del Sud (INFN-LNS). A new method to measure the time scale of the emission of nuclear fragments is described, together with some applications in the field of the isospin dynamics of heavy-ion collisions. Competition between fusion-like and binary reactions near the energy threshold for nuclear multifragmentation is discussed. Opportunities are pointed out to use the detector at low and intermediate energies using the kinematical-coincidence method.

  16. A study of tungsten spectra using large helical device and compact electron beam ion trap in NIFS

    SciTech Connect (OSTI)

    Morita, S.; Goto, M.; Murakami, I. [National Institute for Fusion Science, Toki 509-5292, Gifu (Japan); Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu (Japan); Dong, C. F.; Kato, D.; Sakaue, H. A.; Oishi, T. [National Institute for Fusion Science, Toki 509-5292, Gifu (Japan); Hasuo, M. [Department of Mechanical Engineering and Science, Graduate School of Engineering, Kyoto University, Kyoto 606-8501 (Japan); Koike, F. [Physics Laboratory, School of Medicine, Kitasato University, Sagamihara 252-0374 (Japan); Nakamura, N. [Institute of Laser Science, University of Electro-Communications, Tokyo 182-8585 (Japan); Sasaki, A. [Quantum Beam Science Directorate, Japan Atomic Energy Research Agency, Kizugawa 619-0215, Kyoto (Japan); Wang, E. H. [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu (Japan)

    2013-07-11T23:59:59.000Z

    Tungsten spectra have been observed from Large Helical Device (LHD) and Compact electron Beam Ion Trap (CoBIT) in wavelength ranges of visible to EUV. The EUV spectra with unresolved transition array (UTA), e.g., 6g-4f, 5g-4f, 5f-4d and 5p-4d transitions for W{sup +24-+33}, measured from LHD plasmas are compared with those measured from CoBIT with monoenergetic electron beam ({<=}2keV). The tungsten spectra from LHD are well analyzed based on the knowledge from CoBIT tungsten spectra. The C-R model code has been developed to explain the UTA spectra in details. Radial profiles of EUV spectra from highly ionized tungsten ions have been measured and analyzed by impurity transport simulation code with ADPAK atomic database code to examine the ionization balance determined by ionization and recombination rate coefficients. As the first trial, analysis of the tungsten density in LHD plasmas is attempted from radial profile of Zn-like WXLV (W{sup 44+}) 4p-4s transition at 60.9A based on the emission rate coefficient calculated with HULLAC code. As a result, a total tungsten ion density of 3.5 Multiplication-Sign 10{sup 10}cm{sup -3} at the plasma center is reasonably obtained. In order to observe the spectra from tungsten ions in lower-ionized charge stages, which can give useful information on the tungsten influx in fusion plasmas, the ablation cloud of the impurity pellet is directly measured with visible spectroscopy. A lot of spectra from neutral and singly ionized tungsten are observed and some of them are identified. A magnetic forbidden line from highly ionized tungsten ions has been examined and Cd-like WXXVII (W{sup 26+}) at 3893.7A is identified as the ground-term fine-structure transition of 4f{sup 23}H{sub 5}-{sup 3}H{sub 4}. The possibility of {alpha} particle diagnostic in D-T burning plasmas using the magnetic forbidden line is discussed.

  17. HEAVY ION FUSION SCIENCE VIRTUAL NATIONAL LABORATORY 4th QUARTER 2008 MILESTONE REPORT

    E-Print Network [OSTI]

    Bieniosek, F.M.

    2008-01-01T23:59:59.000Z

    beam carrying 35.8 mA with a 0.7 mA/µsec droop associatedwith the droop of the Marx voltage over this period. From

  18. Neutron Scattering Science User Office, neutronusers@ornl.gov or (865) 574-4600. Proposals for beam time at Oak Ridge National Laboratory's High Flux Isotope Reactor (HFIR)

    E-Print Network [OSTI]

    Pennycook, Steve

    Neutron Scattering Science User Office, neutronusers@ornl.gov or (865) 574-4600. Proposals for beam Wildgruber, wildgrubercu@ornl.gov. VISION CallforProposals neutrons.ornl.gov Neutron Scattering Science - Oak time at Oak Ridge National Laboratory's High Flux Isotope Reactor (HFIR) and Spallation Neutron Source

  19. Measurements of the intercombination and forbidden lines from helium-like ions in Tokamaks and Electron Beam Ion Traps

    SciTech Connect (OSTI)

    Bitter, M; Hill, K W; von Goeler, S; Stodiek, W; Beiersdorfer, P; Rice, J E; Ince-Cushman, A

    2007-08-22T23:59:59.000Z

    The paper reviews the results from tokamak experiments for the line ratios x/w, y/w, and z/w from helium-like ions with Z in the range from 14 to 28. With exception of the DITE experiments, where these line ratios were found to be in agreement with theoretical predictions, all other tokamak experiments yielded values that were significantly larger than predicted. The reasons for these discrepancies are not yet understood. It is possible that radial profile effects were not properly taken into account in the majority of the tokamak experiments. The paper also gives a short historical review of the X-ray diagnostic developments and also presents very recent data from a new type of X-ray imaging crystal spectrometer, which records spatially resolved spectra with a spatial resolution of about 1 cm in the plasma. These new data can be Abel inverted, so that it will be possible to determine line ratios at each radial position in the plasma. Effects of radial profiles, which may have affected the chord-integrated measurements of the past, will thus be eliminated in the future.

  20. SIMULATION OF CLUSTER IMPACT INDUCED DESORPTION AND COOLING Surrey Ion Beam Centre

    E-Print Network [OSTI]

    Webb, Roger P.

    caused by a high energy C60 impact can eject a large polystyrene molecule without fragmentation spectrometry (SIMS) as a probing beam is showing great promise for the analysis of large organic molecules on ejection. Unlike the sputtering process this desorption process does not require that the binding energy

  1. Comparison of SOFC Cathode Microstructure Quantified using X-ray Nanotomography and Focused Ion Beam - Scanning Electron Microscopy

    SciTech Connect (OSTI)

    Nelson, George J.; Harris, William H.; Lombardo, Jeffrey J.; Izzo, Jr., John R.; Chiu, W. K. S.; Tanasini, Pietro; cantoni, Marco; Van herle, Jan; Comninellis, Christos; Andrews, Joy C.; Liu, Yijin; Pianetta, Piero; Chu, Yong

    2011-01-01T23:59:59.000Z

    X-ray nanotomography and focused ion beam scanning electron microscopy (FIB?SEM) have been applied to investigate the complex 3D microstructure of solid oxide fuel cell (SOFC) electrodes at spatial resolutions of 45 nm and below. The application of near edge differential absorption for x-ray nanotomography and energy selected backscatter detection for FIB–SEM enable elemental mapping within the microstructure. Using these methods, non?destructive 3D x-ray imaging and FIB–SEM serial sectioning have been applied to compare three?dimensional elemental mapping of the LSM, YSZ, and pore phases in the SOFC cathode microstructure. The microstructural characterization of an SOFC cathode is reported based on these measurements. The results presented demonstrate the viability of x-ray nanotomography as a quantitative characterization technique and provide key insights into the SOFC cathode microstructure.

  2. Radial profile measurements of plasma pressure-like fluctuations with the heavy ion beam diagnostic on the tokamak ISTTOK

    SciTech Connect (OSTI)

    Henriques, R. B., E-mail: rhenriques@ipfn.ist.utl.pt; Malaquias, A.; Nedzelskiy, I. S.; Silva, C.; Coelho, R.; Figueiredo, H.; Fernandes, H. [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa (Portugal)

    2014-11-15T23:59:59.000Z

    The Heavy Ion Beam Diagnostic (HIBD) on the tokamak ISTTOK (Instituto Superior Técnico TOKamak) has been modified, in terms of signal conditioning, to measure the local fluctuations of the n{sub e}?{sub 1,2}(T{sub e}) product (plasma density times the effective ionization cross-section) along the tokamak minor diameter, in 12 sample volumes in the range of ?0.7a < r < 0.7a, with a maximum delay time of 1 ?s. The corresponding signals show high correlation with the magnetic Mirnov coils in the characteristic MHD frequency range of ISTTOK plasmas and enable the identification of tearing modes. This paper describes the HIBD signal conditioning system and presents a preliminary analysis of the radial profile measurements of local n{sub e}?{sub 1,2}(T{sub e}) fluctuations.

  3. An innovative accelerator-driven inertial electrostatic confinement device using converging ion beams

    SciTech Connect (OSTI)

    Bauer, T. H.; Wigeland, R. A.

    1999-12-08T23:59:59.000Z

    Fundamental physics issues facing development of fusion power on a small-scale are assessed with emphasis on the idea of Inertial Electrostatic Confinement (IEC). The authors propose a new concept of accelerator-driven IEC fusion, termed Converging Beam Inertial Electrostatic Confinement (CB-IEC). CB-IEC offers a number of innovative features that make it an attractive pathway toward resolving fundamental physics issues and assessing the ultimate viability of the IEC concept for power generation.

  4. Current-driven ion-acoustic and potential-relaxation instabilities excited in plasma plume during electron beam welding

    SciTech Connect (OSTI)

    Trushnikov, D. N., E-mail: trdimitr@yandex.ru [The department for Applied Physics, Perm National Research Polytechnic University, Perm, 614990 (Russian Federation); Mladenov, G. M., E-mail: gmmladenov@abv.bg; Koleva, E. G., E-mail: eligeorg@abv.bg [Institute of Electronics, Bulgarian Academy of Sciences, 72 Tzarigradsko Shose, 1784, Sofia (Bulgaria); Technology Centre of Electron Beam and Plasma Technologies and Techniques, 68-70 Vrania, ap.10, Banishora,1309, Sofia (Bulgaria); Belenkiy, V. Ya., E-mail: mtf@pstu.ru; Varushkin, S. V., E-mail: stepan.varushkin@mail.ru [The department for Welding Production and Technology of Constructional Materials, Perm National Research Polytechnic University, Perm, 614990 (Russian Federation)

    2014-04-15T23:59:59.000Z

    Many papers have sought correlations between the parameters of secondary particles generated above the beam/work piece interaction zone, dynamics of processes in the keyhole, and technological processes. Low- and high-frequency oscillations of the current, collected by plasma have been observed above the welding zone during electron beam welding. Low-frequency oscillations of secondary signals are related to capillary instabilities of the keyhole, however; the physical mechanisms responsible for the high-frequency oscillations (>10 kHz) of the collected current are not fully understood. This paper shows that peak frequencies in the spectra of the collected high-frequency signal are dependent on the reciprocal distance between the welding zone and collector electrode. From the relationship between current harmonics frequency and distance of the collector/welding zone, it can be estimated that the draft velocity of electrons or phase velocity of excited waves is about 1600 m/s. The dispersion relation with the properties of ion-acoustic waves is related to electron temperature 10 000 K, ion temperature 2 400 K and plasma density 10{sup 16} m{sup ?3}, which is analogues to the parameters of potential-relaxation instabilities, observed in similar conditions. The estimated critical density of the transported current for creating the anomalous resistance state of plasma is of the order of 3 A·m{sup ?2}, i.e. 8 mA for a 3–10 cm{sup 2} collector electrode. Thus, it is assumed that the observed high-frequency oscillations of the current collected by the positive collector electrode are caused by relaxation processes in the plasma plume above the welding zone, and not a direct demonstration of oscillations in the keyhole.

  5. Ion beam modifications of near-surface compositions in ternary alloys

    SciTech Connect (OSTI)

    Lam, N.Q.; Tang, S.; Yacout, A.M.; Rehn, L.E. (Argonne National Lab., IL (USA)); Stubbins, J.F. (Illinois Univ., Urbana, IL (USA))

    1990-11-01T23:59:59.000Z

    Changes in the surface and subsurface compositions of ternary alloys during elevated-temperature sputtering with inert-gas ions were investigated. Theoretically, a comprehensive kinetic model which includes all the basic processes, such as preferential sputtering, displacement mixing, Gibbsian segregation, radiation-enhanced diffusion and radiation-induced segregation, was developed. This phenomenological approach enabled to predict the effects of each individual process or of a combination of processes on the compositional modification in model alloys. Experimentally, measurements of compositional changes at the surface of a Ag-40at%Au -- 20at%Cu alloy during 3-keV Ne{sup +} bombardment at various temperatures were made, using ion scattering spectroscopy. These measurements were interpreted on the basis of the results of theoretical modeling. 8 refs., 2 figs.

  6. Smoothing metallic glasses without introducing crystallization by gas cluster ion beam

    SciTech Connect (OSTI)

    Shao, Lin; Chen, Di; Myers, Michael; Wang, Jing [Department of Nuclear Engineering and Materials Science and Engineering Program, Texas A and M University, College Station, Texas 77843 (United States)] [Department of Nuclear Engineering and Materials Science and Engineering Program, Texas A and M University, College Station, Texas 77843 (United States); Tilakaratne, Buddhi; Wijesundera, Dharshana; Chu, Wei-Kan [Department of Physics and Texas Center for Superconductivity, University of Houston, Houston, Texas 77004 (United States)] [Department of Physics and Texas Center for Superconductivity, University of Houston, Houston, Texas 77004 (United States); Xie, Guoqiang [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan)] [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Zare, Arezoo; Lucca, Don A. [School of Mechanical and Aerospace Engineering, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)] [School of Mechanical and Aerospace Engineering, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)

    2013-03-11T23:59:59.000Z

    We show that 30 keV Ar cluster ion bombardment of Ni{sub 52.5}Nb{sub 10}Zr{sub 15}Ti{sub 15}Pt{sub 7.5} metallic glass (MG) can remove surface mountain-like features and reduce the root mean square surface roughness from 12 nm to 0.7 nm. X-ray diffraction analysis reveals no crystallization after cluster ion irradiation. Molecular dynamics simulations show that, although damage cascades lead to local melting, the subsequent quenching rate is a few orders of magnitude higher than the critical cooling rate for MG formation, thus the melted zone retains its amorphous nature down to room temperature. These findings can be applied to obtain ultra-smooth MGs without introducing crystallization.

  7. Controlling charge and current neutralization of an ion beam pulse in a background plasma by application of a solenoidal magnetic field

    E-Print Network [OSTI]

    Kaganovich, Igor

    . This condition typically holds for relatively small magnetic fields about 100 G . Analytical formulas are derived,8 magnetic fusion based on field reversed configura- tions fueled by energetic ion beams,9 the physics by application of a solenoidal magnetic field: Weak magnetic field limit I. D. Kaganovich, E. A. Startsev, A. B

  8. Smoothing of Si{sub 0.7}Ge{sub 0.3} virtual substrates by gas-cluster-ion beam

    SciTech Connect (OSTI)

    Chen, H.; Chen, F.; Wang, X.M.; Yu, X.K.; Liu, J.R.; Ma, K.B.; Chu, W.K.; Cheng, H.H.; Yu, I.S.; Ho, Y.T.; Horng, K.Y. [Department of Physics and Texas Center for Superconductivity at University of Houston, University of Houston, Houston, Texas 77204 (United States); Center for Condensed Matter Sciences and Institute of Electronic Engineering, National Taiwan University, Taipei, Taiwan (China); Chung-Shan Institute of Science and Technology, Tao-Yuan, Taiwan (China)

    2005-09-05T23:59:59.000Z

    The planarization of the SiGe virtual substrate surface is crucial for the fabrication of high-performance strained-Si metal-oxide-semiconductor field-effect transistors. In this letter, we report on the smoothing of the inherently crosshatched rough surfaces of SiGe deposited by molecular beam epitaxy on Si substrates by gas cluster ion beams. Atomic force microscopy measurements show that the average surface roughness (R{sub a}) of the SiGe layer could be reduced considerably from 3.2 to 0.7 nm without any crosshatched pattern. Rutherford backscattering in combination with channeling was used to study the damage produced by cluster bombardment. No visible surface damage was observed for the normal-incidence smoothed SiGe with postsmoothing glancing angle cluster ion beam etching.

  9. Fuel ion ratio measurements in reactor relevant neutral beam heated fusion plasmas

    SciTech Connect (OSTI)

    Hellesen, C.; Eriksson, J.; Conroy, S.; Ericsson, G.; Skiba, M.; Weiszflog, M. [Department of Physics and Astronomy, Applied Nuclear Physics, Uppsala University, Uppsala (Sweden); Collaboration: JET-EFDA Contributors

    2012-10-15T23:59:59.000Z

    In this paper, we present a method to derive n{sub t}/n{sub d} using the ratio of the thermonuclear neutron emission to the beam-target neutron emission. We apply it to neutron spectroscopy data from the magnetic proton recoil spectrometer taken during the deuterium tritium experiment at JET. n{sub t}/n{sub d}-values obtained using neutron spectroscopy are in qualitative agreement with those from other diagnostics measuring the isotopic composition of the exhaust in the divertor.

  10. Polarity-inverted ScAlN film growth by ion beam irradiation and application to overtone acoustic wave (000-1)/(0001) film resonators

    SciTech Connect (OSTI)

    Suzuki, Masashi; Yanagitani, Takahiko, E-mail: yana@nitech.ac.jp [Graduate School of Engineering, Nagoya Institute of Technology, Nagoya 466-8555 (Japan); Odagawa, Hiroyuki [Kumamoto National College of Technology, Kumamoto 861-1102 (Japan)

    2014-04-28T23:59:59.000Z

    Polarity inversion in wurtzite film is generally achieved by the epitaxial growth on a specific under-layer. We demonstrate polarity inversion of c-axis oriented ScAlN films by substrate ion beam irradiation without using buffer layer. Substrate ion beam irradiation was induced by either sputtering a small amount of oxide (as a negative ion source) onto the cathode or by applying a RF bias to the substrate. Polarity of the films was determined by a press test and nonlinear dielectric measurement. Second overtone thickness extensional mode acoustic resonance and suppression of fundamental mode resonance, indicating complete polarity inversion, were clearly observed in bilayer highly oriented (000-1)/(0001) ScAlN film.

  11. Local control of magnetic damping in ferromagnetic/non-magnetic bilayers by interfacial intermixing induced by focused ion-beam irradiation

    SciTech Connect (OSTI)

    King, J. A.; Burn, D. M.; Sallabank, E. A.; Hindmarch, A. T.; Atkinson, D., E-mail: del.atkinson@durham.ac.uk, E-mail: abarman@bose.res.in [Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Ganguly, A.; Pal, S.; Barman, A., E-mail: del.atkinson@durham.ac.uk, E-mail: abarman@bose.res.in [Thematic Unit of Excellence on Nanodevice Technology and Department of Condensed Matter Physics and Material Sciences, S.N. Bose National Centre for Basic Sciences, Salt Lake, Kolkata 700 098 (India); Hase, T. P. A. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom)

    2014-06-16T23:59:59.000Z

    The influence of interfacial intermixing on the picosecond magnetization dynamics of ferromagnetic/non-magnetic thin-film bilayers was studied. Low-dose focused-ion-beam irradiation was used to induce intermixing across the interface between a 10?nm Ni{sub 81}Fe{sub 19} layer and a 2–3?nm capping layer of either Au or Cr. Time-resolved magneto-optical Kerr effect was used to study magnetization dynamics as a function of ion-beam dose. With an Au cap, the damping of the un-irradiated bilayer was comparable with native Ni{sub 81}Fe{sub 19} and increased with increasing ion dose. In contrast, for Ni{sub 81}Fe{sub 19}/Cr the damping was higher than that for native Ni{sub 81}Fe{sub 19}, but the damping decreased with increasing dose.

  12. Experiments with planar inductive ion source meant for creation ofH+ Beams

    SciTech Connect (OSTI)

    Vainionpaa, J.H.; Kalvas, T.; Hahto, S.K.; Reijonen, J.

    2007-02-07T23:59:59.000Z

    In this article the effect of different engineering parameters of an rf-driven ion sources with external spiral antenna and quartz disk rf-window are studied. Paper consists of three main topics: The effect of source geometry on the operation gas pressure, the effect of source materials and magnetic confinement on extracted current density and ion species and the effect of different antenna geometries on the extracted current density. The operation gas pressure as a function of the plasma chamber diameter, was studied. This was done with three cylindrical plasma chambers with different inner diameters. The chamber materials were studied using two materials, aluminum and alumina (AlO{sub 2}). The removable 14 magnet multicusp confinement arrangement enabled us to compare the effects of the two wall materials with and without the magnetic confinement. Highest proton fraction of {approx} 8% at 2000 W of rf-power and at pressure of 1.3 Pa was measured using AlO{sub 2} plasma chamber and no multicusp confinement. For all the compared ion sources at 1000W of rf-power, source with multicusp confinement and AlO2 plasma chamber yields highest current density of 82.7 mA/cm{sup 2} at operation pressure of 4 Pa. From the same source highest measured current density of 143 mA/cm{sup 2} at 1.3 Pa and 2200W of rf-power was achieved. Multicusp confinement increased the maximum extracted current up to factor of two. Plasma production with different antenna geometries was also studied. Antenna tests were performed using same source geometry as in source material study with AlO{sub 2} plasma chamber and multicusp confinement. The highest current density was achieved with 4.5 loop solenoid antenna with 6 cm diameter. Slightly lower current density with lower pressure was achieved using tightly wound 3 loop spiral antenna with 3.3 cm ID and 6 cm OD.

  13. Anomalous Electron Transport Due to Multiple High Frequency Beam Ion Driven Alfven Eigenmode

    SciTech Connect (OSTI)

    N.N. Gorelenkov, D. Stutman, K. Tritz, A. Boozer, L. Delgardo-Aparicio, E. Fredrickson, S. Kaye, and R. White

    2010-07-13T23:59:59.000Z

    We report on the simulations of recently observed correlations of the core electron transport with the sub-thermal ion cyclotron frequency instabilities in low aspect ratio plasmas of the National Spherical Torus Experiment (NSTX). In order to model the electron transport of the guiding center code ORBIT is employed. A spectrum of test functions of multiple core localized Global shear Alfven Eigenmode (GAE) instabilities based on a previously developed theory and experimental observations is used to examine the electron transport properties. The simulations exhibit thermal electron transport induced by electron drift orbit stochasticity in the presence of multiple core localized GAE.

  14. Fast Faraday cup to measure neutralized drift compression in intense ion charge bunches A. B. Sefkow, R. C. Davidson, P. C. Efthimion, and E. P. Gilson

    E-Print Network [OSTI]

    Gilson, Erik

    , Princeton, New Jersey 08543, USA S. S. Yu, P. K. Roy, F. M. Bieniosek, J. E. Coleman, S. Eylon, W. G. Sefkow, R. C. Davidson, P. C. Efthimion, and E. P. Gilson Plasma Physics Laboratory, Princeton University-emittance and variable-perveance K ion beam capable of up to 400 keV of directed energy. The ion beam was passed through

  15. The universe in the laboratory - Nuclear astrophysics opportunity at the facility for antiproton and ion research

    SciTech Connect (OSTI)

    Langanke, K. [GSI Helmholtzzentrum für Schwerionenforschung, Technische Universität Darmstadt, Frankfurt Institute of Advanced Studies, D-64291 Darmstadt (Germany)

    2014-05-09T23:59:59.000Z

    In the next years the Facility for Antiproton and Ion Research FAIR will be constructed at the GSI Helmholtzze-ntrum für Schwerionenforschung in Darmstadt, Germany. This new accelerator complex will allow for unprecedented and pathbreaking research in hadronic, nuclear, and atomic physics as well as in applied sciences. This manuscript will discuss some of these research opportunities, with a focus on supernova dynamics and nucleosynthesis.

  16. Testing of optical diagnostics for ion-beam-driven WDM experiments at NDCX-1

    SciTech Connect (OSTI)

    Ni, P.A.; Bieniosek, F.M.; Leitner, M.; Weber, C.; Waldron, W.L.

    2008-06-01T23:59:59.000Z

    We report on the testing of optical diagnostics developed for warm-dense-matter (WDM) experiments on the Neutralized Drift Compression Experiments (NDCX-1) at Lawrence Berkeley National Laboratory (LBNL). The diagnostics consist of a fast optical pyrometer, a streak camera spectrometer, and a VISAR.While the NDCX is in the last stage of commissioning for the target experiments, the diagnostics were tested elsewhere in an experiment where an intense laser pulse was used to generate the WDM state in metallic and carbon samples.

  17. The Research Program at RIBRAS (Radioactive Ion Beams in Brasil)-III

    SciTech Connect (OSTI)

    Lichtenthaeler, R.; Lepine-Szily, A.; Guimaraes, V.; Faria, P. N. de; Mendes, D. R. Jr; Pires, K. C. C.; Morcelle, V.; Barioni, A.; Morais, M. C.; Pampa Condori, R. [Instituto de Fisica da USP, Sao Paulo, Brazil, C.P. 66318, 05314-970 (Brazil); Assuncao, M. [Departamento de Ciencias Exatas e da Terra, Unifesp, Campus de Diadema, Sao Paulo (Brazil); Moro, A. M. [Departamento de FAMN, Universidad de Sevilla, Apdo. 1065, E-41080, Sevilla (Spain); Rodriguez-Gallardo, M. [Departamento de FAMN, Universidad de Sevilla, Apdo. 1065, E-41080, Sevilla (Spain); Instituto de Estructura de la Materia, CSIC, Serrano 123, E-28006 Madrid (Spain); Arazi, A. [Laboratorio TANDAR, Comision Nacional de Energia Atomica (Argentina)

    2010-04-30T23:59:59.000Z

    A part of the research program developed in the RIBRAS facility over the last four years is presented. Experiments using radioactive secondary beams of light exotic nuclei such as {sup 6}He, {sup 7}Be, {sup 8}Li on several targets have been performed. Elastic angular distributions have been analysed by the Optical Model and four body Continuous Discretized Coupled Channels Calculations (4b-CDCC) and the total reaction cross sections have been obtained. A comparison between the reaction cross sections of {sup 6}He and other stable projectiles with medium-heavy targets was performed. Measurements of the proton transfer reaction {sup 12}C({sup 8}Li,{sup 9}Be){sup 11}B are also presented.

  18. COMPUTED TOMOGRAPHIC RECONSTRUCTION OF BEAM PROFILES WITH A MULTI-WIRE CHAMBER

    E-Print Network [OSTI]

    Alonso, J.R.

    2010-01-01T23:59:59.000Z

    the beam with a small ion chamber. Both of these techniquesstudies of the chamber. A for heav;' ion radiotherapy beam

  19. Multi-dimensional collective effects in high-current relativistic beams relevant to High Density Laboratory Plasmas

    SciTech Connect (OSTI)

    Shvets, Gennady

    2014-05-09T23:59:59.000Z

    In summary, an analytical model describing the self-pinching of a relativistic charge-neutralized electron beam undergoing the collisionless Weibel instability in an overdense plasma has been developed. The model accurately predicts the final temperature and size of the self-focused filament. It is found that the final temperature is primarily defined by the total beam’s current, while the filament’s radius is shown to be smaller than the collisionless skin depth in the plasma and primarily determined by the beam’s initial size. The model also accurately predicts the repartitioning ratio of the initial energy of the beam’s forward motion into the magnetic field energy and the kinetic energy of the surrounding plasma. The density profile of the final filament is shown to be a superposition of the standard Bennett pinch profile and a wide halo surrounding the pinch, which contains a significant fraction of the beam’s electrons. PIC simulations confirm the key assumption of the analytic theory: the collisionless merger of multiple current filaments in the course of the Weibel Instability provides the mechanism for Maxwellization of the beam’s distribution function. Deviations from the Maxwell-Boltzmann distribution are explained by incomplete thermalization of the deeply trapped and halo electrons. It is conjectured that the simple expression derived here can be used for understanding collsionless shock acceleration and magnetic field amplification in astrophysical plasmas.

  20. Development of a radio frequency ion source with multi-helicon plasma injectors for neutral beam injection system of Versatile Experiment Spherical Torus

    SciTech Connect (OSTI)

    Choe, Kyumin; Jung, Bongki [Department of Nuclear Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of)] [Department of Nuclear Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of); Chung, Kyoung-Jae, E-mail: jkjlsh1@snu.ac.kr [Center for Advance Research in Fusion Reactor Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of)] [Center for Advance Research in Fusion Reactor Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of); Hwang, Y. S. [Department of Nuclear Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of) [Department of Nuclear Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of); Center for Advance Research in Fusion Reactor Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of)

    2014-02-15T23:59:59.000Z

    Despite of high plasma density, helicon plasma has not yet been applied to a large area ion source such as a driver for neutral beam injection (NBI) system due to intrinsically poor plasma uniformity in the discharge region. In this study, a radio-frequency (RF) ion source with multi-helicon plasma injectors for high plasma density with good uniformity has been designed and constructed for the NBI system of Versatile Experiment Spherical Torus at Seoul National University. The ion source consists of a rectangular plasma expansion chamber (120 × 120 × 120 mm{sup 3}), four helicon plasma injectors with annular permanent magnets and RF power system. Main feature of the source is downstream plasma confinement in the cusp magnetic field configuration which is generated by arranging polarities of permanent magnets in the helicon plasma injectors. In this paper, detailed design of the multi-helicon plasma injector and plasma characteristics of the ion source are presented.

  1. Simulation of neutron displacement damage in bipolar junction transistors using high-energy heavy ion beams.

    SciTech Connect (OSTI)

    Doyle, Barney Lee; Buller, Daniel L.; Hjalmarson, Harold Paul; Fleming, Robert M; Bielejec, Edward Salvador; Vizkelethy, Gyorgy

    2006-12-01T23:59:59.000Z

    Electronic components such as bipolar junction transistors (BJTs) are damaged when they are exposed to radiation and, as a result, their performance can significantly degrade. In certain environments the radiation consists of short, high flux pulses of neutrons. Electronics components have traditionally been tested against short neutron pulses in pulsed nuclear reactors. These reactors are becoming less and less available; many of them were shut down permanently in the past few years. Therefore, new methods using radiation sources other than pulsed nuclear reactors needed to be developed. Neutrons affect semiconductors such as Si by causing atomic displacements of Si atoms. The recoiled Si atom creates a collision cascade which leads to displacements in Si. Since heavy ions create similar cascades in Si we can use them to create similar damage to what neutrons create. This LDRD successfully developed a new technique using easily available particle accelerators to provide an alternative to pulsed nuclear reactors to study the displacement damage and subsequent transient annealing that occurs in various transistor devices and potentially qualify them against radiation effects caused by pulsed neutrons.

  2. Spectroscopy at the high-energy electron beam ion trap (Super EBIT)

    SciTech Connect (OSTI)

    Widmann, K.; Beiersdorfer, P.; Crespo Lopez-Urrutia, J.R.

    1996-07-10T23:59:59.000Z

    The following progress report presents some of the x-ray measurements performed during the last year on the Livermore SuperEBIT facility. The measurements include: direct observation of the spontaneous emission of the hyperfine transition in ground state hydrogenlike holmium, {sup 165}Ho{sup 66{plus}}; measurements of the n {equals} 2 {r_arrow} 2 transition energies in neonlike thorium, Th{sup 80{plus}}, through lithiumlike thorium, Th{sup 87{plus}}, testing the predictions of quantum electrodynamical contributions in high-Z ions up to the 0.4{percent} level; measurements of the isotope shift of the n= 2 {r_arrow} 2 transition energies between lithiumlike through carbonize uranium, {sup 233}U{sup 89{plus}...86{plus}} and {sup 238}U{sup 89{plus}...86{plus}}, inferring the variation of the mean- square nuclear charge radius; and high-resolution measurements of the K{alpha} radiation of heliumlike xenon, Xe{sup 52 {plus}}, using a transmission-type crystal spectrometer, resolving for the first time the ls2p{sup 3}P{sub 1} {r_arrow} 1S{sup 2} {sup 1}S{sub 0} and ls2s{sup 3}S{sub 1} {r_arrow} 1S{sup 2} {sup 1}S{sub 0} transitions individually. 41 refs., 9 figs., 1 tab.

  3. Patient-specific QA and delivery verification of scanned ion beam at NIRS-HIMAC

    SciTech Connect (OSTI)

    Furukawa, Takuji; Inaniwa, Taku; Hara, Yousuke; Mizushima, Kota; Shirai, Toshiyuki; Noda, Koji [Medical Physics Research Group, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan)] [Medical Physics Research Group, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan)

    2013-12-15T23:59:59.000Z

    Purpose: To evaluate a patient-specific QA program and system for constancy checking of a scanning delivery system developed at the National Institute of Radiological Sciences.Methods: For the patient-specific QA, all the planned beams are recalculated on a water phantom with treatment planning software (TPS). The recalculated dose distributions are compared with the measured distributions using a 2D ionization chamber array at several depths, and evaluated using gamma index analysis with criteria of 3% and 3 mm and a pass rate of 90%. For the constancy check, the authors developed the multiwire proportional chamber (MWPC), which can record the delivered 2D fluence images in a slice-by-slice manner. During irradiation for dosimetric QA with the 2D ionization chamber array and an accordion-type water phantom, the 2D fluence images are recorded using the MWPC in the delivery system. These recorded images are then compared to those taken in the treatment session to check the constancy check. This analysis also employs gamma index analysis using the same criteria as in the patient-specific QA. These patient-specific QA and constancy check evaluations were performed using the data of 122 patients.Results: In the patient-specific QA, the measured dose distributions agreed well with those calculated by the TPS, and the QA criteria were satisfied in all measurements. The additional check of the fluence comparison ensured the constancy of the delivered field during each treatment irradiation.Conclusions: The authors established a patient-specific QA program and additional check of delivery constancy in every treatment session. Fluence comparison is a strong tool for constancy checking of the delivery system.

  4. A 915 MHz/2. 45 GHz ECR plasma source for large area ion beam and plasma processing

    SciTech Connect (OSTI)

    Asmussen, J.; Hopwood, J.; Sze, F.C. (Department of Electrical Engineering, Michigan State University, East Lansing, Michigan 48824-1226 (US))

    1990-01-01T23:59:59.000Z

    The technology for producing uniform, high density (10{sup 11}--10{sup 12}/cm{sup 3}) microwave discharges over cross sections of 50 cm{sup 2} is well established. The present challenge is to extend the high density, and electrodeless benefits of microwave discharges to produce uniform densities over an area of 300--700 cm{sup 2}. Such discharges have important applications for 6 to 8-in. single wafer processing and as large surface, broad beam, high current density ion sources. The design principles for scaling the 18 cm diam MPDR ECR cavity applicator technology to 38--47 cm diam are reviewed. Microwave discharges with diameters of 20--30 cm can be created when these applicators are excited with either 2.45 GHz or 915 MHz. The design and construction of a prototype cavity applicator with a 20 cm diam discharge is described. The discharge is enclosed with a 12-pole multicusp static magnetic field produced by 2-in. by 2-in. by 1-in. rare-earth magnets. Each magnet has a pole face field strength of 3 kG. The experimental test of this plasma source in argon gas excited with 2.45 GHz energy is reviewed.

  5. Focused-ion-beam overlay-patterning of three-dimensional diamond structures for advanced single-photon properties

    SciTech Connect (OSTI)

    Jiang, Qianqing; Liu, Dongqi; Liu, Gangqin; Chang, Yanchun; Li, Wuxia, E-mail: liwuxia@aphy.iphy.ac.cn, E-mail: czgu@aphy.iphy.ac.cn [Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Pan, Xinyu; Gu, Changzhi, E-mail: liwuxia@aphy.iphy.ac.cn, E-mail: czgu@aphy.iphy.ac.cn [Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Collaborative Innovation Center of Quantum Matter, Beijing 100190 (China)

    2014-07-28T23:59:59.000Z

    Sources of single photons are of fundamental importance in many applications as to provide quantum states for quantum communication and quantum information processing. Color centers in diamond are prominent candidates to generate and manipulate quantum states of light, even at room temperature. However, the efficiency of photon collection of the color centers in bulk diamond is greatly reduced by refraction at the diamond/air interface. To address this issue, diamond structuring has been investigated by various methods. Among them, focused-ion-beam (FIB) direct patterning has been recognized as the most favorable technique. But it has been noted that diamond tends to present significant challenges in FIB milling, e.g., the susceptibility of forming charging related artifacts and topographical features. In this work, periodically-positioned-rings and overlay patterning with stagger-superimposed-rings were proposed to alleviate some problems encountered in FIB milling of diamond, for improved surface morphology and shape control. Cross-scale network and uniform nanostructure arrays have been achieved in single crystalline diamond substrates. High quality diamond solid immersion lens and nanopillars were sculptured with a nitrogen-vacancy center buried at the desired position. Compared with the film counterpart, an enhancement of about ten folds in single photon collection efficiency was achieved with greatly improved signal to noise ratio. All these results indicate that FIB milling through over-lay patterning could be an effective approach to fabricate diamond structures, potentially for quantum information studies.

  6. Role of Ion Damage on Unintentional Ca Incorporation During the Plasma-Assisted Molecular-Beam Epitaxy Growth of Dilute Nitrides Using N2/Ar Source Gas Mixtures

    SciTech Connect (OSTI)

    Oye, M. M.; Bank, S. R.; Ptak, A. J.; Reedy, R. C.; Goorsky, M. S.; Holmes Jr., A. L.

    2008-05-01T23:59:59.000Z

    Unintentional Ca incorporation caused by Ca-contaminated substrate surfaces on as-purchased GaAs wafers are known to limit the efficiency of solar cells based on dilute nitride materials. This article focuses on further understanding the conditions and mechanisms by which these Ca impurities incorporate. Plasma-assisted molecular-beam epitaxy utilizing a 1% N{sub 2} in Ar precursor gas mixture was used to grow GaAs at 400 and 580 C, and GaN{sub 0.01}As{sub 0.99} at 400 C. Two plasma operating combinations of rf power and gas flow rate were used to generate different amounts and energies of both ions and other plasma species, while keeping nitrogen incorporation constant. The ions were characterized with a dual-grid, retarding-field ion energy analyzer, and the corresponding ion energy distributions are presented to correlate ions with Ca incorporation. When appropriate, dc-biased deflector plates were used to remove ions during growth. Secondary ion mass spectrometry was used to measure Ca in GaAs and GaN{sub 0.01}As{sub 0.99}. Ca incorporation was observed in the dilute nitride samples, but the effects of ions did not exceed other Ca incorporation mechanisms associated with defects due to both low temperature growth and nitrogen incorporation; however, different neutral active nitrogen species (atomic N and metastable N{sub 2}) may be a factor. Ca incorporation measured in GaAs grown at 400 C with a pure Ar plasma is predominantly due to defects associated with low temperature growth, as opposed to plasma damage caused by the ions. GaAs growths at 580 C without a plasma did not exhibit Ca incorporation, but growth at 580 C with ions from a pure Ar plasma caused Ca incorporation.

  7. Vertical alignment of liquid crystal through ion beam exposure on oxygen-doped SiC films deposited at room temperature

    SciTech Connect (OSTI)

    Son, Phil Kook; Park, Jeung Hun; Kim, Jae Chang; Yoon, Tae-Hoon; Rho, Soon Joon; Jeon, Back Kyun; Shin, Sung Tae; Kim, Jang Sub; Lim, Soon Kwon [School of Electrical Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); LC/OLED Research Team, LCD R and D Center, LCD Business, Samsung Electronics Co. Ltd., Yongin, Gyeonggi-Do 449-711 (Korea, Republic of); Process Development Team, LCD R and D Center, LCD Business, Samsung Electronics Co. Ltd., Yongin, Gyeonggi-Do 449-711 (Korea, Republic of)

    2007-09-03T23:59:59.000Z

    The authors report the vertical alignment of liquid crystal (LC) through the ion beam exposure on amorphous oxygen-doped SiC (SiOC) film surfaces deposited at room temperature. The optical transmittance of these films was similar to that of polyimide layers, but much higher than that of SiO{sub x} films. The light leakage of a LC cell aligned vertically on SiOC films was much lower than those of a LC cell aligned on polyimide layers or other inorganic films. They found that LC molecules align vertically on ion beam treated SiOC film when the roughness of the electrostatic force microscopy (EFM) data is high on the SiOC film surface, while they align homogeneously when the roughness of the EFM data is low.

  8. A new method of measuring the poloidal magnetic and radial electric fields in a tokamak using a laser-accelerated ion-beam trace probe

    SciTech Connect (OSTI)

    Yang, X. Y.; Chen, Y. H.; Lin, C.; Wang, X. G.; Xiao, C. J., E-mail: cjxiao@pku.edu.cn [State Key Labaratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); Wang, L. [Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190 (China); Xu, M. [Center for Fusion Science of Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041 (China)

    2014-11-15T23:59:59.000Z

    Both the poloidal magnetic field (B{sub p}) and radial electric field (E{sub r}) are significant in magnetic confinement devices. In this paper, a new method was proposed to diagnose both B{sub p} and E{sub r} at the same time, which was named Laser-accelerated Ion-beam Trace Probe (LITP). This method based on the laser-accelerated ion beam, which has three properties: large energy spread, short pulse lengths, and multiple charge states. LITP can provide the 1D profiles, or 2D images of both B{sub p} and E{sub r}. In this paper, we present the basic principle and some preliminary theoretical results.

  9. SUMMARY AND RESULTS LETTER REPORT – INDEPENDENT VERIFICATION OF THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PROJECT, PHASE 3: TRENCHES 2, 3, AND 4 BROOKHAVEN NATIONAL LABORATORY UPTON, NEW YORK

    SciTech Connect (OSTI)

    E.M. Harpenau

    2010-11-15T23:59:59.000Z

    5098-LR-02-0 SUMMARY AND RESULTS LETTER REPORT – INDEPENDENT VERIFICATION OF THE HIGH FLUX BEAM REACTOR UNDERGROUND UTILITIES REMOVAL PROJECT, PHASE 3 TRENCHES 2, 3, AND 4 BROOKHAVEN NATIONAL LABORATORY

  10. Investigation of beam transmission in A 9SDH-2 3.0 MV NEC pelletron tandem accelerator

    SciTech Connect (OSTI)

    Deoli, Naresh T.; Kummari, Venkata C.; Pacheco, Jose L.; Duggan, Jerome L.; Glass, Gary A.; McDaniel, Floyd D.; Reinert, Tilo; Rout, Bibhudutta; Weathers, Duncan L. [Ion Beam Modification And Analysis Laboratory, Department of Physics, University of North Texas, Denton, Texas 76203 (United States)

    2013-04-19T23:59:59.000Z

    Electrostatic tandem accelerators are widely used to accelerate ions for experiments in materials science such as high energy ion implantation, materials modification, and analyses. Many applications require high beam current as well as high beam brightness at the target; thus, maximizing the beam transmission through such electrostatic accelerators becomes important. The Ion Beam Modification and Analysis Laboratory (IBMAL) at University of North Texas is equipped with four accelerators, one of which is a 9SDH-2 3.0 MV National Electrostatic Corporation (NEC) Pelletron Registered-Sign tandem accelerator. The tandem accelerator is equipped with three ion sources: one radio frequency-He ion source (Alphatross) and two ion sources of Cs-sputter type, the SNICS II (Source of Negative Ions by Cesium Sputtering) and a Cs-sputter source for trace-element accelerator based mass spectrometry. This work presents a detailed study of the beam transmission of hydrogen, silicon, and silver ions through the accelerator using the SNICS ion source with injection energies ranging from 20 keV to 70 keV. The beam transmission is quantified for three different terminal voltages: 1.5 MV, 2.0 MV and 2.5 MV. For a given terminal voltage, it has been found that beam transmission is strongly dependent on the ion source injector potential. Details of experiments and data analysis are presented.

  11. Numerical and laboratory simulations of auroral acceleration

    SciTech Connect (OSTI)

    Gunell, H.; De Keyser, J. [1Belgian Institute for Space Aeronomy, Avenue Circulaire 3, B-1180 Brussels (Belgium)] [1Belgian Institute for Space Aeronomy, Avenue Circulaire 3, B-1180 Brussels (Belgium); Mann, I. [EISCAT Scientific Association, P.O. Box 812, SE-981 28 Kiruna, Sweden and Department of Physics, Umeå University, SE-901 87 Umeå (Sweden)] [EISCAT Scientific Association, P.O. Box 812, SE-981 28 Kiruna, Sweden and Department of Physics, Umeå University, SE-901 87 Umeå (Sweden)

    2013-10-15T23:59:59.000Z

    The existence of parallel electric fields is an essential ingredient of auroral physics, leading to the acceleration of particles that give rise to the auroral displays. An auroral flux tube is modelled using electrostatic Vlasov simulations, and the results are compared to simulations of a proposed laboratory device that is meant for studies of the plasma physical processes that occur on auroral field lines. The hot magnetospheric plasma is represented by a gas discharge plasma source in the laboratory device, and the cold plasma mimicking the ionospheric plasma is generated by a Q-machine source. In both systems, double layers form with plasma density gradients concentrated on their high potential sides. The systems differ regarding the properties of ion acoustic waves that are heavily damped in the magnetosphere, where the ion population is hot, but weakly damped in the laboratory, where the discharge ions are cold. Ion waves are excited by the ion beam that is created by acceleration in the double layer in both systems. The efficiency of this beam-plasma interaction depends on the acceleration voltage. For voltages where the interaction is less efficient, the laboratory experiment is more space-like.

  12. Atom penetration from a thin film into the substrate during sputtering by polyenergetic Ar{sup +} ion beam with mean energy of 9.4 keV

    SciTech Connect (OSTI)

    Kalin, B.A.; Gladkov, V.P.; Volkov, N.V.; Sabo, S.E. [Moscow Engineering Physics Inst. (Russian Federation)

    1995-12-31T23:59:59.000Z

    Penetration of alien atoms (Be, Ni) into Be, Al, Zr, Si and diamond was investigated under Ar{sup +} ion bombardment of samples having thermally evaporated films of 30--50 nm. Sputtering was carried out using a wide energy spectrum beam of Ar{sup +} ions of 9.4 keV to dose D = 1 {times} 10{sup 16}--10{sup 19} ion/cm{sup 2}. Implanted atom distribution in the targets was measured by Rutherford backscattering spectrometry (RBS) of H{sup +} and He{sup +} ions with energy of 1.6 MeV as well as secondary ion mass-spectrometry (SIMS). During the bombardment, the penetration depth of Ar atoms increases with dose linearly. This depth is more than 3--20 times deeper than the projected range of bombarding ions and recoil atoms. This is a deep action effect. The analysis shows that the experimental data for foreign atoms penetration depth are similar to the data calculated for atom migration through the interstitial site in a field of internal (lateral) compressive stresses created in the near-surface layer of the substrate as a result of implantation. Under these experimental conditions atom ratio r{sub i}/r{sub m} (r{sub i} -- radius of dopant, r{sub m} -- radius target of substrate) can play a principal determining role.

  13. Design of a synchrotron radiation detector for the test beam lines at the Superconducting Super Collider Laboratory

    SciTech Connect (OSTI)

    Hutton, R.D.

    1994-01-01T23:59:59.000Z

    As part of the particle- and momentum-tagging instrumentation required for the test beam lines of the Superconducting Super Collider (SSC), the synchrotron radiation detector (SRD) was designed to provide electron tagging at momentum above 75 GeV. In a parallel effort to the three test beam lines at the SSC, schedule demands required testing and calibration operations to be initiated at Fermilab. Synchrotron radiation detectors also were to be installed in the NM and MW beam lines at Femilab before the test beam lines at the SSC would become operational. The SRD is the last instrument in a series of three used in the SSC test beam fines. It follows a 20-m drift section of beam tube downstream of the last silicon strip detector. A bending dipole just in of the last silicon strip detector produces the synchrotron radiation that is detected in a 50-mm-square cross section NaI crystal. A secondary scintillator made of Bicron BC-400 plastic is used to discriminate whether it is synchrotron radiation or a stray particle that causes the triggering of the NaI crystal`s photo multiplier tube (PMT).

  14. Commissioning of the EBIS-based heavy ion preinjector at Brookhaven

    SciTech Connect (OSTI)

    Alessi, J.; Beebe, E.; Binello, S.; Hoff, L.; Kondo, K.; Lambiase, R.; LoDestro, V.; Mapes, M.; McNerney, A.; Morris, J.; Okamura, M.; Pikin, A.I.; Raparia, D.; Ritter, J.; Smart, L.; Snydstrup, L.; Wilinski, M.; Zaltsman, A.; Schempp, A.; Ratzinger, U.; Kanesue, T.

    2010-09-12T23:59:59.000Z

    The status is presented of the commissioning of a new heavy ion preinjector at Brookhaven National Laboratory. This preinjector uses an Electron Beam Ion Source (EBIS), and an RFQ and IH Linac, both operating at 100.625 MHz, to produce 2 MeV/u ions of any species for use, after further acceleration, at the Relativistic Heavy Ion Collider (RHIC) and the NASA Space Radiation Laboratory (NSRL). Among the increased capabilities provided by this preinjector are the ability to produce ions of any species, and the ability to switch between multiple species in 1 second, to simultaneously meet the needs of both science programs. For initial setup, helium beam from EBIS was injected and circulated in the Booster synchrotron. Following this, accelerated Au{sup 32+} and Fe{sup 20+} beams were transported to the Booster injection point, fulfilling DOE requirements for project completion.

  15. Low-energy run of Fermilab Electron Cooler's beam generation system

    SciTech Connect (OSTI)

    Prost, Lionel; Shemyakin, Alexander; /Fermilab; Fedotov, Alexei; Kewisch, Jorg; /Brookhaven

    2010-08-01T23:59:59.000Z

    As a part of a feasibility study of using the Fermilab Electron Cooler for a low-energy Relativistic Heavy Ion Collider (RHIC) run at Brookhaven National Laboratory (BNL), the cooler operation at 1.6 MeV electron beam energy was tested in a short beam line configuration. The main result of the study is that the cooler beam generation system is suitable for BNL needs. In a striking difference with running 4.3 MeV beam, no unprovoked beam recirculation interruptions were observed.

  16. Methods of Beam Cooling

    E-Print Network [OSTI]

    Sessler, A. M.

    2008-01-01T23:59:59.000Z

    of Optical Stochastic Cooling", presented at PAC, (1995).1991). Hangst, J. , "Laser Cooling of a Stored Ion Beam - ATheorem and Phase Space Cooling", Proceedings of the

  17. Ion Beam Materials Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch > The Energy Materials Center atdiffusivities in mesopores

  18. Ion beam-assisted pulsed laser deposition of (Ba,Sr)(Ti,Zr)O{sub 3} films on Pt-Si substrates

    SciTech Connect (OSTI)

    Sakai, Joe; Vayunandana Reddy, Y. K.; Autret-Lambert, Cecile; Lagrange, Jean-Francois; Motret, Olivier; Roger, Sylvain; Wolfman, Jerome [Laboratoire LEMA, UMR 6157 CNRS-CEA, Universite Francois Rabelais de Tours, Parc de Grandmont, 37200 Tours (France)

    2011-05-15T23:59:59.000Z

    Ion beam-assisted pulsed laser deposition with an Ar-oxygen ion mixture was used to prepare Ba{sub 0.6}Sr{sub 0.4}Ti{sub 0.7}Zr{sub 0.3}O{sub 3} (BSTZ) thin films on Pt-coated Si substrates. The ion beam with an anode voltage of 600 V was effective to reduce the thermal budget, i.e., to achieve similar crystallinity with approximately 100 deg. C lower deposition temperature compared to the cases without ionization. It was revealed that the dielectric properties (relative dielectric constant {epsilon}{sub r} and its electric field tunability), out-of-plane lattice parameter of (001)-oriented grains (a{sub 001}), and the existence of (110)-oriented grains are correlated with one another. Elongation of a{sub 001} was suppressed, resulting in large {epsilon}{sub r} values comparable with that of a ceramic bulk of the same composition, in the BSTZ films that contain (110)-oriented grains. Less volume of amorphous BSTZ region is supposed to be playing an important role for the bulklike properties of these BSTZ films.

  19. H{sup -} beam transport experiments in a solenoid low energy beam transport

    SciTech Connect (OSTI)

    Gabor, C. [ASTeC Intense Beams Group, Rutherford Appleton Laboratory, Chilton, Didcot - Oxfordshire OX11 0QX (United Kingdom); Back, J. J. [High Energy Physics Department, University of Warwick, Coventry CV4 7AL (United Kingdom); Faircloth, D. C.; Lawrie, S. R.; Letchford, A. P. [ISIS Pulsed Spallation Neutron Source, Rutherford Appleton Laboratory, Chilton, Didcot - Oxfordshire OX11 0QX (United Kingdom); Izaola, Z. [ESS Bilbao, Accelerator Physics Group, Edificio Cosimet Paseo Landabarri, 2, 1 Planta. 48940 Leioa (Spain)

    2012-02-15T23:59:59.000Z

    The Front End Test Stand (FETS) is located at Rutherford Appleton Laboratory and aims for a high current, fast chopped 3 MeV H{sup -} ion beam suitable for future high power proton accelerators like ISIS upgrade. The main components of the front end are the Penning ion source, a low energy beam transport line, an radio-frequency quadrupole (RFQ) and a medium energy beam transport (MEBT) providing also a chopper section and rebuncher. FETS is in the stage of commissioning its low energy beam transport (LEBT) line consisting of three solenoids. The LEBT has to transport an H{sup -} high current beam (up to 60 mA) at 65 keV. This is the injection energy of the beam into the RFQ. The main diagnostics are slit-slit emittance scanners for each transversal plane. For optimizing the matching to the RFQ, experiments have been performed with a variety of solenoid settings to better understand the actual beam transport. Occasionally, source parameters such as extractor slit width and beam energy were varied as well. The paper also discusses simulations based on these measurements.

  20. Rabi Waves and Peculiarities of Raman Scattering in Carbon Nanotubes, Produced by High Energy Ion Beam Modification of Diamond Single Crystals

    E-Print Network [OSTI]

    Dmitry Yearchuck; Alla Dovlatova

    2011-03-06T23:59:59.000Z

    QED-model for multichain coupled qubit system, proposed in \\cite{Part1}, was confirmed by Raman scattering studies of carbon zigzag-shaped nanotubes, produced by high energy ion beam modification of natural diamond single crystals. New quantum optics phenomenon - Rabi waves - has been experimentally identified for the first time. Raman spectra in perfect quasi-1D carbon nanotubes are quite different in comparison with well known Raman spectra in 2D carbon nanotubes of larger diameter. They characterized by vibronic mode of Su-Schriffer-Heeger $\\sigma$-polaron lattice and its revival part in frequency representation, which is the consequence of Rabi wave packet formation.

  1. Heavy-ion broad-beam and microprobe studies of single-event upsets in 0.20 um SiGe heterojunction bipolar transistors and circuits.

    SciTech Connect (OSTI)

    Fritz, Karl (Mayo Foundation, Rochester, MN); Irwin, Timothy J. (Jackson & Tull Chartered Engineers, Washington, DC); Niu, Guofu (Auburn University, Auburn, AL); Fodness, Bryan (SGT, Inc., Greenbelt, MD); Carts, Martin A. (Raytheon ITSS, Greenbelt, MD); Marshall, Paul W. (Brookneal, VA); Reed, Robert A. (NASA/GSFC, Greenbelt, MD); Gilbert, Barry (Mayo Foundation, Rochester, MN); Randall, Barbara (Mayo Foundation, Rochester, MN); Prairie, Jason (Mayo Foundation, Rochester, MN); Riggs, Pam (Mayo Foundation, Rochester, MN); Pickel, James C. (PR& T, Inc., Fallbrook, CA); LaBel, Kenneth (NASA/GSFC, Greenbelt, MD); Cressler, John D. (Georgia Institute of Technology, Atlanta, GA); Krithivasan, Ramkumar (Georgia Institute of Technology, Atlanta, GA); Dodd, Paul Emerson; Vizkelethy, Gyorgy

    2003-09-01T23:59:59.000Z

    Combining broad-beam circuit level single-event upset (SEU) response with heavy ion microprobe charge collection measurements on single silicon-germanium heterojunction bipolar transistors improves understanding of the charge collection mechanisms responsible for SEU response of digital SiGe HBT technology. This new understanding of the SEU mechanisms shows that the right rectangular parallele-piped model for the sensitive volume is not applicable to this technology. A new first-order physical model is proposed and calibrated with moderate success.

  2. Type A verification report for the high flux beam reactor stack and grounds, Brookhaven National Laboratory, Upton, New York

    SciTech Connect (OSTI)

    Harpenau, Evan M.

    2012-01-13T23:59:59.000Z

    The U.S. Department of Energy (DOE) Order 458.1 requires independent verification (IV) of DOE cleanup projects (DOE 2011). The Oak Ridge Institute for Science and Education (ORISE) has been designated as the responsible organization for IV of the High Flux Beam Reactor (HFBR) Stack and Grounds area at Brookhaven National Laboratory (BNL) in Upton, New York. The IV evaluation may consist of an in-process inspection with document and data reviews (Type A Verification) or a confirmatory survey of the site (Type B Verification). DOE and ORISE determined that a Type A verification of the documents and data for the HFBR Stack and Grounds: Survey Units (SU) 6, 7, and 8 was appropriate based on the initial survey unit classification, the walkover surveys, and the final analytical results provided by the Brookhaven Science Associates (BSA). The HFBR Stack and Grounds surveys began in June 2011 and were completed in September 2011. Survey activities by BSA included gamma walkover scans and sampling of the as-left soils in accordance with the BSA Work Procedure (BNL 2010a). The Field Sampling Plan - Stack and Remaining HFBR Outside Areas (FSP) stated that gamma walk-over surveys would be conducted with a bare sodium iodide (NaI) detector, and a collimated detector would be used to check areas with elevated count rates to locate the source of the high readings (BNL 2010b). BSA used the Mult- Agency Radiation Survey and Site Investigation Manual (MARSSIM) principles for determining the classifications of each survey unit. Therefore, SUs 6 and 7 were identified as Class 1 and SU 8 was deemed Class 2 (BNL 2010b). Gamma walkover surveys of SUs 6, 7, and 8 were completed using a 2?2 NaI detector coupled to a data-logger with a global positioning system (GPS). The 100% scan surveys conducted prior to the final status survey (FSS) sampling identified two general soil areas and two isolated soil locations with elevated radioactivity. The general areas of elevated activity identified were investigated further with a collimated NaI detector. The uncollimated average gamma count rate was less than 15,000 counts per minute (cpm) for the SU 6, 7, and 8 composite area (BNL 2011a). Elevated count rates were observed in portions of each survey unit. The general areas of elevated counts near the Building 801 ventilation and operations and the entry to the Stack were determined to be directly related to the radioactive processes in those structures. To compensate for this radioactive shine, a collimated or shielded detector was used to lower the background count rate (BNL 2011b and c). This allowed the surveyor(s) to distinguish between background and actual radioactive contamination. Collimated gamma survey count rates in these shine affected areas were below 9,000 cpm (BNL 2011a). The average background count rate of 7,500 cpm was reported by BSA for uncollimated NaI detectors (BNL 2011d). The average collimated background ranged from 4,500-6,500 cpm in the westernmost part of SU 8 and from 2,000-3,500 cpm in all other areas (BNL 2011e). Based on these data, no further investigations were necessary for these general areas. SU 8 was the only survey unit that exhibited verified elevated radioactivity levels. The first of two isolated locations of elevated radioactivity had an uncollimated direct measurement of 50,000 cpm with an area background of 7,500 cpm (BNL 2011f). The second small area exhibiting elevated radiation levels was identified at a depth of 6 inches from the surface. The maximum reported count rate of 28,000 cpm was observed during scanning (BNL 2011g). The affected areas were remediated, and the contaminated soils were placed in an intermodal container for disposal. BSA's post-remediation walkover surveys were expanded to include a 10-foot radius around the excavated locations, and it was determined that further investigation was not required for these areas (BNL 2011 f and g). The post-remediation soil samples were collected and analyzed with onsite gamma spectroscopy equipment. These samples were also included with the FSS s

  3. High-pressure arcs as vacuum-atmosphere interface and plasma lens for nonvacuum electron beam welding machines, electron beam melting, and nonvacuum ion material modification

    SciTech Connect (OSTI)

    Hershcovitch, A. [AGS Department, Brookhaven National Laboratory, Upton, New York 11973-5000 (United States)] [AGS Department, Brookhaven National Laboratory, Upton, New York 11973-5000 (United States)

    1995-11-01T23:59:59.000Z

    Atmospheric pressure plasmas can be used to provide a vacuum-atmosphere interface as an alternative to differential pumping. Vacuum-atmosphere interface utilizing a cascade arc discharge was successfully demonstrated and a 175 keV electron beam was successfully propagated from vacuum through such a plasma interface and out into atmospheric pressure. Included in the article are a theoretical framework, experimental results, and possible applications for this novel interface. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  4. SU-E-T-172: Evaluation of the Exradin A26 Ion Chamber in Megavoltage Photon Beams as a Reference Class Instrument

    SciTech Connect (OSTI)

    McEwen, M [National Research Council, Ottawa, ON (Canada)

    2014-06-01T23:59:59.000Z

    Purpose: The Exradin A26 is a new design of micro-ionization ion chamber that externally resembles the Exradin A16 model but has significant internal changes to address measurement issues reported in the literature for the A16. This project involved the characterization of two versions of the A26 chamber in high energy x-rays with particular reference to the performance specification laid out in the imminent Addendum to TG-51. Methods: The Exradin A26 was investigated in a range of megavoltage photon beams (6–25 MV). Investigations looked at chamber settling, ion recombination and polarity. Since it has been previously shown that non-ideal performance is most easily identified through ion recombination measurements, the focus was on the determination of Pion. Results: i) Chamber settling - the chamber response stabilizes very quickly (within 3 minutes), even after a large change in the polarizing voltage.ii) The polarity correction was found to be small (within 0.2% of unity)iii) The chamber showed linear behavior for a Jaffe plot (1/reading vs 1/polarizing voltage) for applied voltages ? 200 V.iv) The recombination correction showed a linear variation with the doseper- pulse, was not significantly dependent on the polarity of the collecting voltage and was consistent with the chamber dimensions (i.e. agreed with Boag theory). Conclusion: An initial investigation of the Exradin A26 micro chamber suggests that although its performance exceeds the AAPM specification for a reference-class ion chamber for use in megavoltage photon beams it is a significant improvement over the previous A16 design. Further work is required to evaluate long-term stability and determine kQ factors.

  5. Atomic Beam Merging and Suppression of Alkali Contaminants in Multi Body High Power Targets: Design and Test of Target and Ion Source Prototypes at ISOLDE

    E-Print Network [OSTI]

    Bouquerel, Elian J A; Lettry, J; Stora, T

    2009-01-01T23:59:59.000Z

    The next generation of high power ISOL-facilities will deliver intense and pure radioactive ion beams. Two key issues of developments mandatory for the forthcoming generation of ISOL target-ion source units are assessed and demonstrated in this thesis. The design and production of target and ion-source prototypes is described and dedicated measurements at ISOLDE-CERN of their radioisotope yields are analyzed. The purity of short lived or rare radioisotopes suffer from isobaric contaminants, notably alkalis which are highly volatile and easily ionized elements. Therefore, relying on their chemical nature, temperature controlled transfer lines were equipped with a tube of quartz that aimed at trapping these unwanted elements before they reached the ion source. The successful application yields high alkali-suppression factors for several elements (ie: 80, 82mRb, 126, 142Cs, 8Li, 46K, 25Na, 114In, 77Ga, 95, 96Sr) for quartz temperatures between 300ºC and 1100ºC. The enthalpies of adsorption on quartz were measu...

  6. Astrophysics experiments with radioactive beams at ATLAS

    SciTech Connect (OSTI)

    Back, B. B.; Clark, J. A.; Pardo, R. C.; Rehm, K. E., E-mail: rehm@anl.gov; Savard, G. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States)] [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

    2014-04-15T23:59:59.000Z

    Reactions involving short-lived nuclei play an important role in nuclear astrophysics, especially in explosive scenarios which occur in novae, supernovae or X-ray bursts. This article describes the nuclear astrophysics program with radioactive ion beams at the ATLAS accelerator at Argonne National Laboratory. The CARIBU facility as well as recent improvements for the in-flight technique are discussed. New detectors which are important for studies of the rapid proton or the rapid neutron-capture processes are described. At the end we briefly mention plans for future upgrades to enhance the intensity, purity and the range of in-flight and CARIBU beams.

  7. Surface plasmon polariton modes in a single-crystal Au nanoresonator fabricated using focused-ion-beam milling

    E-Print Network [OSTI]

    Polman, Albert

    to 30 keV, and focused by an electrostatic lens system to a spot size with diameter as small as 5­10 nm, photovoltaics, tele- communications, and optoelectronic circuit integration due to their ability to concentrate.5,6 In a typical FIB system, Ga+ ions are extracted from a liquid-metal ion source, accel- erated

  8. Spark-protected ion-source control and monitoring system at 1. 5 MV

    SciTech Connect (OSTI)

    Bogaty, J.M.; Zolecki, R.

    1981-01-01T23:59:59.000Z

    The Heavy Ion Fusion Program at Argonne National Laboratory utilizes a 1.5-MV Xe ion preaccelerator. Reliable beam transport requires accurate measurements and precise control of various ion-source parameters. This paper discusses the use of a multiplexed fiberoptic data-transmission system and low-cost digital stepper motors for control functions. Techniques are discussed which allow TTL and CMOS semiconductor curcuits to survive the destructive sparks which can occur in the 1.5-MV preaccelerator.

  9. Dual and Triple Ion-Beam Irradiations of Fe, Fe(Cr) and Fe(Cr)-ODS Final Report: IAEA SMoRE CRP

    SciTech Connect (OSTI)

    Fluss, M J; Hsiung, L L; Marian, J

    2011-11-20T23:59:59.000Z

    Structures of nanoparticles in Fe-16Cr-4.5Al-0.3Ti-2W-0.37Y2O3 (K3) and Fe-20Cr-4.5Al-0.34Ti-0.5Y2O3 (MA956) oxide dispersion strengthened (ODS) ferritic steels produced by mechanical alloying (MA) and followed by hot extrusion have been studied using high-resolution transmission electron microscopy (HRTEM) techniques to gain insight about the formation mechanism of nanoparticles in MA/ODS steels. The observations of Y-Al-O complex-oxide nanoparticles in both ODS steels imply that decomposition of Y2O3 in association with internal oxidation of Al occurred during mechanical alloying. While the majority of oxide nanoparticles formed in both steels is Y4Al2O9, a few oxide particles of YAlO3 are also occasionally observed. These results reveal that Ti (0.3 wt %) plays an insignificant role in forming oxide nanoparticles in the presence of Al (4.5 wt %). HRTEM observations of crystalline nanoparticles larger than {approx}2 nm and amorphous or disordered cluster domains smaller than {approx}2 nm provide an insight into the formation mechanism of oxide nanoparticle in MA/ODS steels, which we believe from our observations involves a solid-state amorphous precursor followed by recrystallization. Dual ion-beam irradiations using He{sup +} + Fe{sup +8} ions were employed to gain more detailed insight about the role of nanoparticles in suppressing radiation-induced swelling. This is elaborated through TEM examinations of cavity distributions in ion-irradiated Fe-14Cr and K3-ODS ferritic steels. HRTEM observations of helium-filled cavities (helium bubbles) preferably trapped at nanoscale oxide particles and clusters in ion-irradiated K3-ODS are presented. Finally, we describe the results from triple ion-beam irradiations using H{sup +} + He{sup +} + Fe{sup +8} ions to emulate fusion first wall radiation effects. Preliminary work is reported that confirms the existence of significant hydrogen synergistic effects described earlier by Tanaka et al., for Fe(Cr) and by Wakai et al., for F82H reduced activation ferritic martensitic (RAF/M) steel. These previous results combined with our data suggest a complex new 'catalytic' mechanism whereby H interacts with the steady state population of defects and the embryonic cavities so as to accelerated cavity (void) growth in both Fe(Cr) and under special conditions in ODS steels.

  10. TYPE A VERIFICATION REPORT FOR THE HIGH FLUX BEAM REACTOR STACK AND GROUNDS, BROOKHAVEN NATIONAL LABORATORY, UPTON, NEW YORK DCN 5098-SR-08-0

    SciTech Connect (OSTI)

    Evan Harpenau

    2011-11-30T23:59:59.000Z

    The U.S. Department of Energy (DOE) Order 458.1 requires independent verification (IV) of DOE cleanup projects (DOE 2011). The Oak Ridge Institute for Science and Education (ORISE) has been designated as the responsible organization for IV of the High Flux Beam Reactor (HFBR) Stack and Grounds area at Brookhaven National Laboratory (BNL) in Upton, New York. The IV evaluation may consist of an in-process inspection with document and data reviews (Type A Verification) or a confirmatory survey of the site (Type B Verification). DOE and ORISE determined that a Type A verification of the documents and data for the HFBR Stack and Grounds: Survey Units (SU) 6, 7, and 8 was appropriate based on the initial survey unit classification, the walkover surveys, and the final analytical results provided by the Brookhaven Science Associates (BSA).

  11. Recent results from the EBIT and Super EBIT at Lawrence Livermore National Laboratory

    SciTech Connect (OSTI)

    Marrs, R.E.

    1996-10-07T23:59:59.000Z

    The electron beam ion trap (EBIT), and the higher-energy Super EBIT at Lawrence Livermore National Laboratory can produce any highly charged ion. These highly charged ions are used in a variety of research programs. Recent results from four different experiments are reviewed here. K-shell ionization cross sections have been measured for the hydrogenlike ions of several elements, and L-shell ionization cross sections have been measured for uranium ions. A measurement of the ground-state hyperfine transition in hydrogenlike {sup 165}H{sup 66+} is notable because of the complete absence of Doppler shifts. A cryogenic Penning trap, injected with EBIT ions, has been used to observe a single highly charged ion as it recombines by sequential electron capture from H{sub 2} gas. A large sputtered ion yield, suggesting a surface Coulomb explosion, has been observed from insulators bombarded with very highly charged EBIT ions. 21 refs., 11 figs.

  12. Ion-molecule interactions in crossed-beams. [N/sup +/-H/sub 2/; F/sup +/-H; CO/sub 2//sup +/-D/sub 2/

    SciTech Connect (OSTI)

    Hansen, S.G.

    1980-09-01T23:59:59.000Z

    Interactions of the ions N/sup +/, F/sup +/, and CO/sub 2//sup +/ with H/sub 2/ and/or its isotopes were examined using the crossed-beam technique in the low (< 4 eV) initial relative energy. For the reaction N/sup +/(/sup 3/P) + H/sub 2/ ..-->.. NH/sup +/ + H, complex formation dominates up to 1.9 eV and a substantial interaction occurs between all collision partners up to 3.6 eV. The distribution of N/sup +/ scattered nonreactively from H/sub 2/ also showed a long-lived complex channel below 1.9 eV. The reaction F/sup +/(/sup 3/P) + H/sub 2/ ..-->..FH/sup +/ + H proceeded by a direct reaction mechanism at 0.20 to 1.07 eV. The reaction CO/sub 2//sup +/ + D/sub 2/ ..-->.. DCO/sub 2//sup +/ + D gives asymmetric product distributions at 0.27 eV and above, indicating a direct reaction mechanism. Results indicated that there are probably barriers in the exit channels for DCO/sub 2//sup +/, DCO/sup +/, and D/sub 2/O/sup +/ products. The electronic state distributions of the N/sup +/, F/sup +/, and CO/sub 2//sup +/ beams was investigated using beam attenuation and total luminescence techniques.

  13. Towards sub-200?nm nano-structuring of linear giant magneto-resistive spin valves by a direct focused ion beam milling process

    SciTech Connect (OSTI)

    Riedmüller, Benjamin; Huber, Felix; Herr, Ulrich [Institute of Micro and Nanomaterials, Ulm University, 89081 Ulm (Germany)

    2014-02-14T23:59:59.000Z

    In this work, we present a detailed investigation of a focused ion beam (FIB) assisted nano-structuring process for giant magneto-resistive (GMR) spin valve sensors. We have performed a quantitative study of the dependence of the GMR ratio as well as the sensor resistance on the ion dose, which is implanted in the active region of our sensors. These findings are correlated with the decrease of magneto-resistive properties after micro- and nano-structuring by the FIB and reveal the importance of ion damage which limits the applicability of FIB milling to GMR devices in the low ?m range. Deposition of a protective layer (50?nm SiO{sub 2}) on top of the sensor structure before milling leads to a preservation of the magneto-resistive properties after the milling procedure down to sensor dimensions of ?300?nm. The reduction of the sensor dimensions to the nanometer regime is accompanied by a shift of the GMR curves, and a modification of the saturation behavior. Both effects can be explained by a micromagnetic model including the magnetic interaction of free and pinned layer as well as the effect of the demagnetizing field of the free layer on the sensor behavior. The results demonstrate that the FIB technology can be successfully used to prepare spintronic nanostructures.

  14. Ion colliders

    SciTech Connect (OSTI)

    Fischer, W.

    2011-12-01T23:59:59.000Z

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

  15. IRRADIATION CONTROL OF THE "SPIRAL" TARGET BY MEASURING THE ION BEAM INTENSITY VIA A FAST CURRENT TRANSFORMER

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    by the target (integrated flux) should not exceed a certain level, function of the radiological risk. In order of measurement will handle the signal of each sensor so that they can be digitized by a computing system received the maximum dose (new safety criterion). PRINCIPLE OF THE MEASUREMENT OF THE BEAM INTENSITY

  16. Decontamination and dismantlement of the building 594 waste ion exchange facility at Argonne National Laboratory-East project final report.

    SciTech Connect (OSTI)

    Wiese, E. C.

    1998-11-23T23:59:59.000Z

    The Building 594 D&D Project was directed toward the following goals: Removal of any radioactive and hazardous materials associated with the Waste Ion Exchange Facility; Decontamination of the Waste Ion Exchange Facility to unrestricted use levels; Demolition of Building 594; and Documentation of all project activities affecting quality (i.e., waste packaging, instrument calibration, audit results, and personnel exposure) These goals had been set in order to eliminate the radiological and hazardous safety concerns inherent in the Waste Ion Exchange Facility and to allow, upon completion of the project, unescorted and unmonitored access to the area. The ion exchange system and the resin contained in the system were the primary areas of concern, while the condition of the building which housed the system was of secondary concern. ANL-E health physics technicians characterized the Building 594 Waste Ion Exchange Facility in September 1996. The characterization identified a total of three radionuclides present in the Waste Ion Exchange Facility with a total activity of less than 5 {micro}Ci (175 kBq). The radionuclides of concern were Co{sup 60}, Cs{sup 137}, and Am{sup 241}. The highest dose rates observed during the project were associated with the resin in the exchange vessels. DOE Order 5480.2A establishes the maximum whole body exposure for occupational workers at 5 rem (50 mSv)/yr; the administrative limit at ANL-E is 1 rem/yr (10 mSv/yr).

  17. Plasma meniscus and extraction electrode studies of the ISIS H{sup -} ion source

    SciTech Connect (OSTI)

    Lawrie, S. R.; Faircloth, D. C.; Letchford, A. P.; Gabor, C. [ISIS Pulsed Spallation Neutron Source, Rutherford Appleton Laboratory, Oxfordshire OX11 0QX (United Kingdom); Pozimski, J. K. [ISIS Pulsed Spallation Neutron Source, Rutherford Appleton Laboratory, Oxfordshire OX11 0QX (United Kingdom); Department of Physics, Imperial College of Science and Technology, London SW7 2AZ (United Kingdom)

    2010-02-15T23:59:59.000Z

    In order to reduce the emittance and increase the transported beam current from the ISIS Penning-type H{sup -} ion source, improvements to the extraction system are required. This ion source is currently being commissioned on the front end test stand at the Rutherford Appleton Laboratory, which demands higher extraction energies, higher beam currents, and smaller emittances. To facilitate this, the present geometry requires optimization. This paper details the experimental and simulation studies performed of the plasma meniscus and the possible electrode geometry modifications needed to extract the highest quality beam.

  18. RF gas plasma source development for heavy ion fusion

    SciTech Connect (OSTI)

    Ahle, L.E.; Hall, R.P.; Molvik, A.W.

    2002-02-22T23:59:59.000Z

    Presently the Heavy Ion Fusion Virtual National Laboratory is researching ion sources and injector concepts to understand how to optimize beam brightness over a range of currents (50-2000 mA argon equivalent). One concept initially accelerates millimeter size, milliamp beamlets to 1 MeV before merging them into centimeter size, ampere beams. Computer simulations have shown the final brightness of the merged beams is dominated by the emittance growth of the merging process, as long as the beamlets ion temperature is below a few eV. Thus, a RF multicusp source capable of high current density can produce beams with better brightness compared to ones extracted from a colder source with a large aperture and lower current density. As such, experiments have begun to develop a RF multicusp source capable of delivering one amp of extracted beam current. It is expected that it will require 10 kW of 13 MHz RF power delivered via a quartz shielded, one and half turn, four inch diameter antenna. Important considerations in the development of the source include the dependence of current density and beam ion temperature on consumed RF power and gas pressure. A fast rise time ({approx}100 ns) for the extracted beam pulse must also be achieved. Progress on these experiments will be presented.

  19. RF Gas Plasma Source Development for Heavy Ion Fusion

    SciTech Connect (OSTI)

    Ahle, L; Hall, R P; Molvik, A W; Kwan, J W; Leung, K N

    2001-09-04T23:59:59.000Z

    Presently the Heavy Ion Fusion Virtual National Laboratory is researching ion sources and injector concepts to understand how to optimize beam brightness over a range of currents (50-2000 mA argon equivalent). One concept initially accelerates millimeter size, milliamp beamlets to 1 MeV before merging them into centimeter size, ampere beams. Computer simulations have shown the final brightness of the merged beams is dominated by the emittance growth of the merging process, as long as the beamlets ion temperature is below a few eV. Thus, a RF multicusp source capable of high current density can produce beams with better brightness compared to ones extracted from a colder source with a large aperture and lower current density. As such, experiments have begun to develop a RF multicusp source capable of delivering one amp of extracted beam current. It is expected that it will require 10 kW of 13 MHz RF power delivered via a quartz shielded, one and half turn, four inch diameter antenna. Important considerations in the development of the source include the dependence of current density and beam ion temperature on consumed RF power and gas pressure. A fast rise time ({approx} 100 ns) for the extracted beam pulse must also be achieved. Progress on these experiments will be presented.

  20. 2 Dynamic analysis of mixed ion beams/materials effects on the performance 3 of ITER-like devices

    E-Print Network [OSTI]

    Harilal, S. S.

    ions from the core plasma with impurities of 37 beryllium and carbon eroded from PFC can cause erosion from the surface layers, physical sputtering of target 47 atoms, and possible bubble formation of minute impurities like 59carbon, oxygen, or beryllium. These impurities will also influence 60hydrogen

  1. Origin of the energetic ion beams at the substrate generated during high power pulsed magnetron sputtering of titanium

    E-Print Network [OSTI]

    Maszl, Christian; Benedikt, Jan; von Keudell, Achim

    2013-01-01T23:59:59.000Z

    High power pulsed magnetron sputtering (HiPIMS) plasmas generate energetic metal ions at the substrate as a major difference to conventional direct current magnetron sputtering. The origin of these energetic ions in HiPIMS is still an open issue, which is unraveled by using three fast diagnostics: time resolved mass spectrometry with a temporal resolution of 2 $\\mu$s, phase resolved optical emission spectroscopy with 1 $\\mu$s and the rotating shutter experiment with a resolution of 50 $\\mu$s. A power scan from dcMS-like to HiPIMS plasmas was performed, with a 2-inch magnetron and a titanium target as sputter source and argon as working gas. Clear differences in the transport as well in the energetic properties of Ar$^+$, Ar$^{2+}$, Ti$^+$ and Ti$^{2+}$ were observed. For discharges with highest peak power densities a high energetic group of Ti$^{+}$ and Ti$^{2+}$ could be identified. A cold group of ions is always present. It is found that hot ions are observed only, when the plasma enters the spokes regime, ...

  2. Vehicle Technologies Office Merit Review 2015: Post-Test Analysis of Lithium-Ion Battery Materials at Argonne National Laboratory

    Broader source: Energy.gov [DOE]

    Presentation given by Argonne National Laboratory at 2015 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about post-test...

  3. Vehicle Technologies Office Merit Review 2014: Post-Test Analysis of Lithium-Ion Battery Materials at Argonne National Laboratory

    Broader source: Energy.gov [DOE]

    Presentation given by Argonne National Laboratory at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about post-test...

  4. Room temperature magnetoresistance in CoFeB/SrTiO{sub 3}/CoFeB magnetic tunnel junctions deposited by ion beam sputtering

    SciTech Connect (OSTI)

    Hassen, E. M. J. [CEA, LETI, MINATEC Campus, Grenoble (France); SPINTEC (UMR 8191 CEA-CNRS-UJF), CEA-INAC, 38054 Grenoble Cedex (France); Viala, B.; Cyrille, M. C.; Cartier, M.; Redon, O. [CEA, LETI, MINATEC Campus, Grenoble (France); Lima, P. [SPTS, Process Technology Systems, Ringland Way, Newport (United Kingdom); Belhadji, B.; Yang, H. X.; Chshiev, M. [SPINTEC (UMR 8191 CEA-CNRS-UJF), CEA-INAC, 38054 Grenoble Cedex (France); Velev, J. [Department of Physics, University of Puerto Rico, San Juan 00931 (Puerto Rico)

    2012-04-01T23:59:59.000Z

    Room temperature transport properties are reported in polycrystalline SrTiO{sub 3}-based magnetic tunnel junctions deposited by ion beam sputtering. The junctions comprise CoFeB electrodes and the SrTiO{sub 3} barrier with thickness varied between 0.9 and 1.9 nm. Resistance area product values between 3 {Omega}.{mu}m{sup 2} and 22 k{Omega}.{mu}m{sup 2} have been measured with a tunnel magnetoresistance ratio ranging from 3.1 to 13% at room temperature. At low barrier thickness (1.2 nm), ferromagnetic coupling between electrodes is observed, indicating the presence of defects in the structure. A post-oxidation step was found to improve transport properties at lower barrier thickness.

  5. The Cooling of Particle Beams

    E-Print Network [OSTI]

    Sessler, Andrew M.

    2008-01-01T23:59:59.000Z

    67, 15. Hangst, J "Laser Cooling of a Stored Ion Beam - ATheorem an.d Phase Space Cooling", Proceedings of theWorkshop on Beam Cooling and Related Topics, Montreaux, CERN

  6. Analytical and Numerical Studies of the Complex Interaction of a Fast Ion Beam Pulse with a Background Plasma

    E-Print Network [OSTI]

    Kaganovich, Igor

    ]. In this paper, we focus on the nonlinear case where the plasma density has an arbitrary value compared with a Background Plasma Igor D. Kaganovich1 , Edward A. Startsev1 and Ronald C. Davidson1 1 Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA Received September 8, 2003 Abstract Plasma

  7. Chemical Imaging Analysis of Environmental Particles Using the Focused Ion Beam/Scanning Electron Microscopy Technique: Microanalysis Insights into Atmospheric Chemistry of Fly Ash

    SciTech Connect (OSTI)

    Chen, Haihan; Grassian, Vicki H.; Saraf, Laxmikant V.; Laskin, Alexander

    2013-01-21T23:59:59.000Z

    Airborne fly ash from coal combustion may represent a source of bioavailable iron (Fe) in the open ocean. However, few studies have been made focusing on Fe speciation and distribution in coal fly ash. In this study, chemical imaging of fly ash has been performed using a dual-beam FIB/SEM (focused ion beam/scanning electron microscope) system for a better understanding of how simulated atmospheric processing modify the morphology, chemical compositions and element distributions of individual particles. A novel approach has been applied for cross-sectioning of fly ash specimen with a FIB in order to explore element distribution within the interior of individual particles. Our results indicate that simulated atmospheric processing causes disintegration of aluminosilicate glass, a dominant material in fly ash particles. Aluminosilicate-phase Fe in the inner core of fly ash particles is more easily mobilized compared with oxide-phase Fe present as surface aggregates on fly ash spheres. Fe release behavior depends strongly on Fe speciation in aerosol particles. The approach for preparation of cross-sectioned specimen described here opens new opportunities for particle microanalysis, particular with respect to inorganic refractive materials like fly ash and mineral dust.

  8. New ion-guide for the production of beams of neutron-rich nucleibetween Z = 20 - 28

    SciTech Connect (OSTI)

    Perajarvi, Kari; Cerny, Joe; Hakala, Jani; Huikari, Jussi; Jokinen, Ari; Karvonen, Pasi; Kurpeta, Jan; Lee, Dongwon; Moore, Ian; Penttila, Heikki; Popov, Andrei; Aysto, Juha

    2004-12-08T23:59:59.000Z

    It has been shown for the first time that quasi- and deep-inelastic reactions can be successfully incorporated into the conventional Ion-Guide Isotope Separator On-Line (IGISOL) technique. This is of particular interest for characterizing the decay properties of refractory elements and is applied to neutron rich nuclei between Z = 20-28. As a first step of this project, the kinematics of quasi- and deep-inelastic reactions, such as {sup 197}Au({sup 65}Cu,X)Y, were studied. Based on these studies, a specialized IGISOL target chamber was designed and built. This chamber was tested in on- and off-line conditions at the Jyvaskyla IGISOL facility. Yields of radioactive, projectile-like species such as {sup 62,63}Co are about 0.8 ions/s/pnA corresponding to a total IGISOL efficiency of about 0.06%.

  9. Chemical reactions of conformationally selected 3-aminophenol molecules in a beam with Coulomb-crystallized Ca{sup +} ions

    SciTech Connect (OSTI)

    Rösch, Daniel; Willitsch, Stefan, E-mail: stefan.willitsch@unibas.ch [Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel (Switzerland)] [Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel (Switzerland); Chang, Yuan-Pin [Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg (Germany)] [Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg (Germany); Küpper, Jochen, E-mail: jochen.kuepper@cfel.de [Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg (Germany) [Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg (Germany); Department of Physics, University of Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany); The Hamburg Center for Ultrafast Imaging, University of Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany)

    2014-03-28T23:59:59.000Z

    Many molecules exhibit multiple conformers that often easily interconvert under thermal conditions. Therefore, single conformations are difficult to isolate which renders the study of their distinct chemical reactivities challenging. We have recently reported a new experimental method for the characterization of conformer-specific effects in chemical reactions [Y.-P. Chang, K. D?ugo??cki, J. Küpper, D. Rösch, D. Wild, and S. Willitsch, “Specific chemical reactivities of spatially separated 3-aminophenol conformers with cold Ca{sup +} ions,” Science 342, 98–101 (2013)]. Different conformers are spatially separated using inhomogeneous electric fields and reacted with a Coulomb crystal of cold, spatially localized ions in a trap. As a first application, we studied reactions between the two conformers of 3-aminophenol and Ca{sup +}. We observed a twofold larger rate constant for the cis compared to the trans conformer which was rationalized in terms of the differences in the long-range ion-molecule interactions. The present article provides a detailed description of the new method and a full account of the experimental results as well as the accompanying theoretical calculations.

  10. alloy ion source: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ions at radioactive ion beam facilities is discussed. The ability to combine high efficiency and element selectivity makes a resonance ionization laser ion source (RILIS) an...

  11. ambient ion sources: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ions at radioactive ion beam facilities is discussed. The ability to combine high efficiency and element selectivity makes a resonance ionization laser ion source (RILIS) an...

  12. Effects of arrival rate and gas pressure on the chemical bonding and composition in titanium nitride films prepared on Si(100) substrates by ion beam and vapor deposition

    SciTech Connect (OSTI)

    Matsuoka, M.; Isotani, S.; Mittani, J.C.R.; Chubaci, J.F.D.; Ogata, K.; Kuratani, N. [Institute of Physics, University of Sao Paulo, C. P. 66318, 05315-970, Sao Paolo, SP (Brazil); Nissin Electric Company, Ltd., 47, Umezu-Takase-cho, Ukyo-ku, Kyota 615-8686 (Japan)

    2005-01-01T23:59:59.000Z

    Thin titanium nitride films were prepared at room temperature by titanium metal vapor deposition on silicon substrates with simultaneous irradiation by a 2 keV nitrogen ion beam. Arrival rate ratios, ARR(N/Ti), defined as the ratio of the flux of incident atomic nitrogen particles in the ion beam relative to the flux of titanium atoms transported to the substrate, ranged from 0.17 to 2.5. The gas pressure in the vacuum chamber was maintained at 1.3x10{sup -3} or 6.7x10{sup -3} Pa during the deposition and irradiation process. Analyses of Ti 2p x-ray photoelectron spectroscopy spectra indicated the presence of metal Ti{sup 0}, nitride TiN, oxide TiO{sub 2}, oxynitride TiN{sub x}O{sub y}, and carbide TiC phases. The Ti{sup 0} phase was observed exclusively and predominantly in the films prepared at 1.3x10{sup -3} Pa and ARR(N/Ti)=0.17, 0.21, and 0.28, and the TiN phase is major in the others, as confirmed by the x-ray diffractometry analyses. The chemical composition ratio N/Ti in the films prepared at 1.3x10{sup -3} Pa increased linearly with increasing ARR(N/Ti) up to ARR(N/Ti)=0.42 and tended to be constant with further increase in ARR(N/Ti), while this ratio in the films prepared at 6.7x10{sup -3} Pa was almost constant independently of ARR(N/Ti), similar to the constant value observed at 1.3x10{sup -3} Pa and higher ARR(N/Ti). This dependence may be understood by comparison with the flux of evaporated titanium atoms, the flux of nitrogen in the beam, and the impingement rate of nitrogen gas in the vacuum chamber, evaluated through the kinetic theory of gases. On the other hand, titanium is known to be one of the chemically active materials which form stable compounds with gases by chemisorption, this fact leading to considerable incorporation of contaminant oxygen and carbon in the depositing titanium film.

  13. Dependence of beam emittance on plasma electrode temperature and rf-power, and filter-field tuning with center-gapped rod-filter magnets in J-PARC rf-driven H{sup ?} ion source

    SciTech Connect (OSTI)

    Ueno, A., E-mail: akira.ueno@j-parc.jp; Koizumi, I.; Ohkoshi, K.; Ikegami, K.; Takagi, A.; Yamazaki, S.; Oguri, H. [J-PARC Center, Tokai-mura, Naka-gun, Ibaraki-ken 319-1195 (Japan)] [J-PARC Center, Tokai-mura, Naka-gun, Ibaraki-ken 319-1195 (Japan)

    2014-02-15T23:59:59.000Z

    The prototype rf-driven H{sup ?} ion-source with a nickel plated oxygen-free-copper (OFC) plasma chamber, which satisfies the Japan Proton Accelerator Research Complex (J-PARC) 2nd stage requirements of a H{sup ?} ion beam current of 60 mA within normalized emittances of 1.5 ? mm mrad both horizontally and vertically, a flat top beam duty factor of 1.25% (500 ?s × 25 Hz) and a life-time of more than 50 days, was reported at the 3rd international symposium on negative ions, beams, and sources (NIBS2012). The experimental results of the J-PARC ion source with a plasma chamber made of stainless-steel, instead of nickel plated OFC used in the prototype source, are presented in this paper. By comparing these two sources, the following two important results were acquired. One was that the about 20% lower emittance was produced by the rather low plasma electrode (PE) temperature (T{sub PE}) of about 120?°C compared with the typically used T{sub PE} of about 200?°C to maximize the beam current for the plasma with the abundant cesium (Cs). The other was that by using the rod-filter magnets with a gap at each center and tuning the gap-lengths, the filter-field was optimized and the rf-power necessary to produce the J-PARC required H{sup ?} ion beam current was reduced typically 18%. The lower rf-power also decreases the emittances.

  14. Beam energy dependence of the expansion dynamics in relativistic heavy ion collisions: Indications for the critical end point?

    E-Print Network [OSTI]

    Roy A. Lacey

    2014-08-06T23:59:59.000Z

    The flow harmonic $v_{n}$ and the emission source radii $R_{\\text{out}}$, $R_{\\text{side}}$ and $R_{\\text{long}}$ are studied for a broad range of centrality selections and beam collision energies in Au+Au ($\\sqrt{s_{NN}}= 7.7 - 200$ GeV) and Pb+Pb ($\\sqrt{s_{NN}}= 2.76$ TeV) collisions at RHIC and the LHC respectively. They validate the acoustic scaling patterns expected for hydrodynamic-like expansion over the entire range of beam energies studied. The combined data sets allow estimates for the \\sqsn\\ dependence of the mean expansion speed $\\left$, emission duration $\\left$ and the viscous coefficients $\\left$ that encode the magnitude of the specific shear viscosity $\\left$. The estimates indicate initial-state model independent values of $\\left$ which are larger for the plasma produced at 2.76 TeV (LHC) compared to that produced at 200 GeV (RHIC) ($\\left_{\\text{LHC}}=2.2\\pm 0.2$ and $\\left_{\\text{RHIC}}=1.3\\pm 0.2$). They also show a non-monotonic \\sqsn\\ dependence for $\\left$, $\\left$ and $\\left$, with minima for $\\left$ and $\\left$, and a complimentary maximum for $\\left$. These dependencies signal a significant change in reaction dynamics in a narrow span of $\\sqrt{s_{NN}}$, which may be linked to reaction trajectories close to the critical end point (CEP) in the phase diagram for nuclear matter.

  15. Synchrotron radiation induced x-ray micro analysis: A realistic alternative for electron- and ion beam microscopy?

    SciTech Connect (OSTI)

    Janssens, K.; Adams, F. [Universitaire Instelling Antwerpen, Antwerp (Belgium). Dept. of Chemistry; Rivers, M.L.; Jones, K.W. [Brookhaven National Lab., Upton, NY (United States)

    1992-10-01T23:59:59.000Z

    Synchrotron Radiation induced X-ray micro Fluorescence analysis ({mu}-SRXRF) is compared with more conventional microanalytical techniques such as Secondary Ion Microscopy (SIMS) and Electron Probe X-ray Microanalysis (EPXMA) for two typical microanalytical applications. SRXRF and EPXMA are employed for the analysis of individual particles, showing the complementary character of both techniques. By means of element mapping of trace constituents in a heterogeneous feldspar, the strong and weak points of SRXRF in comparison to EPXMA and SIMS are illustrated. The most striking difference between SRXRF and the other two microanalytical methods is the ability of SRXRF to probe deep into the investigated Material, whereas SIMS and EPXMA only investigate the upper surface of the material. The possibilities of SRXRF at third generation synchrotron rings is also briefly discussed.

  16. Synchrotron radiation induced x-ray micro analysis: A realistic alternative for electron- and ion beam microscopy

    SciTech Connect (OSTI)

    Janssens, K.; Adams, F. (Universitaire Instelling Antwerpen, Antwerp (Belgium). Dept. of Chemistry); Rivers, M.L.; Jones, K.W. (Brookhaven National Lab., Upton, NY (United States))

    1992-01-01T23:59:59.000Z

    Synchrotron Radiation induced X-ray micro Fluorescence analysis ([mu]-SRXRF) is compared with more conventional microanalytical techniques such as Secondary Ion Microscopy (SIMS) and Electron Probe X-ray Microanalysis (EPXMA) for two typical microanalytical applications. SRXRF and EPXMA are employed for the analysis of individual particles, showing the complementary character of both techniques. By means of element mapping of trace constituents in a heterogeneous feldspar, the strong and weak points of SRXRF in comparison to EPXMA and SIMS are illustrated. The most striking difference between SRXRF and the other two microanalytical methods is the ability of SRXRF to probe deep into the investigated Material, whereas SIMS and EPXMA only investigate the upper surface of the material. The possibilities of SRXRF at third generation synchrotron rings is also briefly discussed.

  17. Integrating a Traveling Wave Tube into an AECR-U ion source

    SciTech Connect (OSTI)

    Covo, Michel Kireeff; Benitez, Janilee Y.; Ratti, Alessandro; Vujic, Jasmina L.

    2011-07-01T23:59:59.000Z

    An RF system of 500W - 10.75 to 12.75 GHz was designed and integrated into the Advanced Electron Cyclotron Resonance - Upgrade (AECR-U) ion source of the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory. The AECR-U produces ion beams for the Cyclotron giving large flexibility of ion species and charge states. The broadband frequency of a Traveling Wave Tube (TWT) allows modifying the volume that couples and heats the plasma. The TWT system design and integration with the AECR-U ion source and results from commissioning are presented.

  18. Core - Corona Model analysis of the Low Energy Beam Scan at RHIC (Relativistic Heavy Ion Collider) in Brookhaven (USA)

    E-Print Network [OSTI]

    M. Gemard; J. Aichelin

    2014-02-02T23:59:59.000Z

    The centrality dependence of spectra of identified particles in collisions between ultrarelativistic heavy ions with a center of mass energy ($\\sqrt{s}$) of 39 and 11.5 $AGeV$ is analyzed in the core - corona model. We show that at these energies the spectra can be well understood assuming that they are composed of two components whose relative fraction depends on the centrality of the interaction: The core component which describes an equilibrated quark gluon plasma and the corona component which is caused by nucleons close to the surface of the interaction zone which scatter only once and which is identical to that observed in proton-proton collisions. The success of this approach at 39 and 11.5 $AGeV$ shows that the physics does not change between this energy and $\\sqrt{s}=200~ AGeV$ for which this model has been developed (Aichelin 2008). This presents circumstantial evidence that a quark gluon plasma is also created at center of mass energies as low as 11.5 $AGeV$.

  19. A Scaled Final Focus Experiment for Heavy Ion Fusion

    SciTech Connect (OSTI)

    MacLaren, Stephan, Alexander

    2000-09-19T23:59:59.000Z

    A one-tenth dimensionally scaled version of a final focus sub-system design for a heavy ion fusion driver is built and tested. By properly scaling the physics parameters that relate particle energy and mass, beam current, beam emittance, and focusing field, the transverse dynamics of a driver scale final focus are replicated in a small laboratory beam. The experiment uses a 95 {micro}A beam of 160 keV Cs{sup +} ions to study the dynamics as the beam is brought to a ballistic focus in a lattice of six quadrupole magnets. Diagnostic stations along the experiment track the evolution of the transverse phase space of the beam. The measured focal spot size is consistent with calculations and the report of the design on which the experiment is based. By uniformly varying the strengths of the focusing fields in the lattice, the chromatic effect of a small energy deviation on the spot size can be reproduced. This is done for {+-}1% and {+-}2% shifts and the changes in the focus are measured. Additionally, a 400 {micro}A beam is propagated through the experiment and partially neutralized after the last magnet using electrons released from a hot tungsten filament. The increase in beam current allows for the observation of significant effects on both the size and shape of the focal spot when the electrons are added.

  20. Effect of discharge current and deposition temperature on roughness and density of NbC films fabricated by ion beam sputtering technique

    SciTech Connect (OSTI)

    Dhawan, Rajnish, E-mail: rajnish@rrcat.gov.in; Rai, Sanjay, E-mail: rajnish@rrcat.gov.in; Lodha, G. S., E-mail: rajnish@rrcat.gov.in [X-ray optics Section, Indus Synchrotron Utilization Division, Raja Ramanna Center for Advanced Technology, Indore-452013 (India)

    2014-04-24T23:59:59.000Z

    NbC films were prepared using Ion beam sputtering system at various discharges current from 0.4 amps to 1.2 amps at room temperature. Effect of temperature on NbC films were also studied by depositing NbC films at various temperatures from room temperature to 200,300,400 and 600°C. X-ray reflectivity (XRR) study shows that surface roughness of the film decreases with decrease in discharge current. The optimum lowest roughness 3.2Å having density 92% of bulk was achieved at discharge current 0.6 amps at 3.0 cm{sup 3}/min Ar gas flow. X-ray study also shows that film roughness decreases with increase in temperature of the film and after a certain temperature it increases with increase in temperature. The lowest surface roughness 2.1Å was achieved at 300°C with density 83% of bulk NbC at constant discharge current 0.6 amps.

  1. First application of the Trojan Horse Method with a Radioactive Ion Beam: study of the $^{18}$F($p,{\\alpha}$)$^{15}$O}} reaction at astrophysical energies

    E-Print Network [OSTI]

    Cherubini, S; Spitaleri, C; Rapisarda, G G; La Cognata, M; Lamia, L; Pizzone, R G; Romano, S; Kubono, S; Yamaguchi, H; Hayakawa, S; Wakabayashi, Y; Iwasa, N; Kato, S; Komatsubara, T; Teranishi, T; Coc, A; de Séréville, N; Hammache, F; Kiss, G; Bishop, S; Binh, D N

    2015-01-01T23:59:59.000Z

    Measurement of nuclear cross sections at astrophysical energies involving unstable species is one of the most challenging tasks in experimental nuclear physics. The use of indirect methods is often unavoidable in this scenario. In this paper the Trojan Horse Method is applied for the first time to a radioactive ion beam induced reaction studying the $^{18}$F($p,{\\alpha}$)$^{15}$O process at low energies relevant to astrophysics via the three body reaction $^{2}$H($^{18}$F,${\\alpha}^{15}$O)n. The knowledge of the $^{18}$F($p, {\\alpha}$)$^{15}$O reaction rate is crucial to understand the nova explosion phenomena. The cross section of this reaction is characterized by the presence of several resonances in $^{19}$Ne and possibly interference effects among them. The results reported in Literature are not satisfactory and new investigations of the $^{18}$F($p,{\\alpha}$)$^{15}$O reaction cross section will be useful. In the present work the spin-parity assignments of relevant levels have been discussed and the astro...

  2. Time-dependent, x-ray spectral unfolds and brightness temperatures for intense Li{sup +} ion beam-driven hohlraums

    SciTech Connect (OSTI)

    Fehl, D.L.; Chandler, G.A.; Biggs, F.; Dukart, R.J.; Moats, A.R.; Leeper, R.J. [Sandia National Laboratories Albuquerque, New Mexico 87185 (United States)] [Sandia National Laboratories Albuquerque, New Mexico 87185 (United States)

    1997-01-01T23:59:59.000Z

    X-ray-producing hohlraums are being studied as indirect drives for inertial confinement fusion targets. In a 1994 target series on the PBFAII accelerator, cylindrical hohlraum targets were heated by an intense Li{sup +} ion beam and viewed by an array of 13 time-resolved, filtered x-ray detectors (XRDs). The unfold operator (UFO) code and its suite of auxiliary functions were used extensively in obtaining time-resolved x-ray spectra and radiation temperatures from this diagnostic. The UFO was also used to obtain fitted response functions from calibration data, to simulate data from blackbody x-ray spectra of interest, to determine the suitability of various unfolding parameters (e.g., energy domain, energy partition, smoothing conditions, and basis functions), to interpolate the XRD signal traces, and to unfold experimental data. The simulation capabilities of the code were useful in understanding an anomalous feature in the unfolded spectra at low photon energies ({le}100 eV). Uncertainties in the differential and energy-integrated unfolded spectra were estimated from uncertainties in the data. The time{endash}history of the radiation temperature agreed well with independent calculations of the wall temperature in the hohlraum. {copyright} {ital 1997 American Institute of Physics.}

  3. Time-dependent, x-ray spectral unfolds and brightness temperatures for intense Li{sup +} ion beam-driven hohlraums

    SciTech Connect (OSTI)

    Fehl, D.L.; Chandler, G.A.; Biggs, F.; Dukart, R.J.; Moats, A.R.; Leeper, R.J.

    1996-07-01T23:59:59.000Z

    X-ray-producing hohlraums are being studied as indirect drives for Inertial Confinement Fusion targets. In a 1994 target series on the PBFAII accelerator, cylindrical hohlraum targets were heated by an intense Li{sup +} ion beam and viewed by an array of 13 time-resolved, filtered x-ray detectors (XRDs). The UFO unfold code and its suite of auxiliary functions were used extensively in obtaining time- resolved x-ray spectra and radiation temperatures from this diagnostic. UFO was also used to obtain fitted response functions from calibration data, to simulate data from blackbody x-ray spectra of interest, to determine the suitability of various unfolding parameters (e.g., energy domain, energy partition, smoothing conditions, and basis functions), to interpolate the XRD signal traces, and to unfold experimental data. The simulation capabilities of the code were useful in understanding an anomalous feature in the unfolded spectra at low photon energies ({le} 100 eV). Uncertainties in the differential and energy-integrated unfolded spectra were estimated from uncertainties in the data. The time-history of the radiation temperature agreed well with independent calculations of the wall temperature in the hohlraum.

  4. Inductively generated streaming plasma ion source

    DOE Patents [OSTI]

    Glidden, Steven C.; Sanders, Howard D.; Greenly, John B.

    2006-07-25T23:59:59.000Z

    A novel pulsed, neutralized ion beam source is provided. The source uses pulsed inductive breakdown of neutral gas, and magnetic acceleration and control of the resulting plasma, to form a beam. The beam supplies ions for applications requiring excellent control of ion species, low remittance, high current density, and spatial uniformity.

  5. Negative hydrogen ion sources for accelerators

    SciTech Connect (OSTI)

    Moehs, D.P.; /Fermilab; Peters, J.; /DESY; Sherman, J.; /Los Alamos

    2005-08-01T23:59:59.000Z

    A variety of H{sup -} ion sources are in use at accelerator laboratories around the world. A list of these ion sources includes surface plasma sources with magnetron, Penning and surface converter geometries as well as magnetic-multipole volume sources with and without cesium. Just as varied is the means of igniting and maintaining magnetically confined plasmas. Hot and cold cathodes, radio frequency, and microwave power are all in use, as well as electron tandem source ignition. The extraction systems of accelerator H{sup -} ion sources are highly specialized utilizing magnetic and electric fields in their low energy beam transport systems to produce direct current, as well as pulsed and/or chopped beams with a variety of time structures. Within this paper, specific ion sources utilized at accelerator laboratories shall be reviewed along with the physics of surface and volume H{sup -} production in regard to source emittance. Current research trends including aperture modeling, thermal modeling, surface conditioning, and laser diagnostics will also be discussed.

  6. Effect of O{sub 2}{sup +}, H{sub 2}{sup +}+ O{sub 2}{sup +}, and N{sub 2}{sup +}+ O{sub 2}{sup +} ion-beam irradiation on the field emission properties of carbon nanotubes

    SciTech Connect (OSTI)

    Acuna, J. J. S.; Alvarez, F. [Instituto de Fisica 'Gleb Wataghin', UNICAMP, P.O. Box 6165 Campinas, SP, 13083-970 (Brazil); Escobar, M. [INQUIMAE, FCEyN-UBA-CONICET, Ciudad Universitaria, Pabellon II, Buenos Aires (Argentina); Depto. Fisica, FECyN, UBA, Ciudad Universitaria, Pabellon II, Buenos Aires (Argentina); Goyanes, S. N. [Depto. Fisica, FECyN, UBA, Ciudad Universitaria, Pabellon II, Buenos Aires (Argentina); Candal, R. J. [INQUIMAE, FCEyN-UBA-CONICET, Ciudad Universitaria, Pabellon II, Buenos Aires (Argentina); ECyT, 3iA, UNSAM, Campus Migueletes, San Martin, Pcia. Buenos Aires (Argentina); Zanatta, A. R. [Instituto de Fisica de Sao Carlos-USP, P.O. Box 369, Sao Carlos 13560-250 (Brazil)

    2011-06-01T23:59:59.000Z

    The effect of O{sub 2}{sup +}, H{sub 2}{sup +}+ O{sub 2}{sup +}, and N{sub 2}{sup +}+ O{sub 2}{sup +} ion-beam irradiation of carbon nanotubes (CNTs) films on the chemical and electronic properties of the material is reported. The CNTs were grown by the chemical vapor deposition technique (CVD) on silicon TiN coated substrates previously decorated with Ni particles. The Ni decoration and TiN coating were successively deposited by ion-beam assisted deposition (IBAD) and afterwards the nanotubes were grown. The whole deposition procedure was performed in situ as well as the study of the effect of ion-beam irradiation on the CNTs by x-ray photoelectron spectroscopy (XPS). Raman scattering, field-effect emission gun scanning electron microscopy (FEG-SEM), and field emission (FE) measurements were performed ex situ. The experimental data show that: (a) the presence of either H{sub 2}{sup +} or N{sub 2}{sup +} ions in the irradiation beam determines the oxygen concentration remaining in the samples as well as the studied structural characteristics; (b) due to the experimental conditions used in the study, no morphological changes have been observed after irradiation of the CNTs; (c) the FE experiments indicate that the electron emission from the CNTs follows the Fowler-Nordheim model, and it is dependent on the oxygen concentration remaining in the samples; and (d) in association with FE results, the XPS data suggest that the formation of terminal quinone groups decreases the CNTs work function of the material.

  7. Negative ion source with low temperature transverse divergence optical system

    DOE Patents [OSTI]

    Whealton, J.H.; Stirling, W.L.

    1985-03-04T23:59:59.000Z

    A negative ion source is provided which has extremely low transverse divergence as a result of a unique ion focusing system in which the focal line of an ion beam emanating from an elongated, concave converter surface is outside of the ion exit slit of the source and the path of the exiting ions. The beam source operates with a minimum ion temperature which makes possible a sharply focused (extremely low transverse divergence) ribbon like negative ion beam.

  8. Negative ion source with low temperature transverse divergence optical system

    DOE Patents [OSTI]

    Whealton, John H. (Oak Ridge, TN); Stirling, William L. (Oak Ridge, TN)

    1986-01-01T23:59:59.000Z

    A negative ion source is provided which has extremely low transverse divergence as a result of a unique ion focusing system in which the focal line of an ion beam emanating from an elongated, concave converter surface is outside of the ion exit slit of the source and the path of the exiting ions. The beam source operates with a minimum ion temperature which makes possible a sharply focused (extremely low transverse divergence) ribbon like negative ion beam.

  9. Vacuum Arc Ion Sources: Recent Developments and Applications

    SciTech Connect (OSTI)

    Brown, Ian; Oks, Efim

    2005-05-01T23:59:59.000Z

    The vacuum arc ion source has evolved over the past twenty years into a standard laboratory tool for the production of high current beams of metal ions, and is now used in a number of different embodiments at many laboratories around the world. The primary application of this kind of source has evolved to be ion implantation for material surface modification. Another important use is for injection of high current beams of heavy metal ions into the front ends of particle accelerators, and much excellent work has been carried out in recent years in optimizing the source for reliable accelerator application. The source also provides a valuable tool for the investigation of the fundamental plasma physics of vacuum arc plasma discharges. As the use of the source has grown and diversified, at the same time the ion source performance and operational characteristics have been improved in a variety of different ways also. Here we review the growth and status of vacuum arc ion sources around the world, and summarize some of the applications for which the sources have been used.

  10. Nufact 2008 The Beta Beam WP Beta beam R&D status

    E-Print Network [OSTI]

    McDonald, Kirk

    Nufact 2008 The Beta Beam WP Nufact 08 1 Beta beam R&D status Elena Wildner, CERN on behalf of the Beta Beam Study Group EURISOL/Euronu #12;Nufact 2008 The Beta Beam WP Nufact08Nufact08 Outline Recall, EURISOL Ion Production Loss Management Improvements New Program, EuroNu 2 #12;Nufact 2008 The Beta Beam WP

  11. Progress in heavy ion driven inertial fusion energy: From scaledexperiments to the integrated research experiment

    SciTech Connect (OSTI)

    Barnard, J.J.; Ahle, L.E.; Baca, D.; Bangerter, R.O.; Bieniosek,F.M.; Celata, C.M.; Chacon-Golcher, E.; Davidson, R.C.; Faltens, A.; Friedman, A.; Franks, R.M.; Grote, D.P.; Haber, I.; Henestroza, E.; deHoon, M.J.L.; Kaganovich, I.; Karpenko, V.P.; Kishek, R.A.; Kwan, J.W.; Lee, E.P.; Logan, B.G.; Lund, S.M.; Meier, W.R.; Molvik, A.W.; Olson, C.; Prost, L.R.; Qin, H.; Rose, D.; Sabbi, G-L.; Sangster, T.C.; Seidl, P.A.; Sharp, W.M.; Shuman, D.; Vay, J.L.; Waldron, W.L.; Welch, D.; Yu, S.S.

    2001-06-22T23:59:59.000Z

    The promise of inertial fusion energy driven by heavy ion beams requires the development of accelerators that produce ion currents ({approx}100s Amperesheam) and ion energies ({approx}1-10 GeV) that have not been achieved simultaneously in any existing accelerator. The high currents imply high generalized perveances, large tune depressions. and high space charge potentials of the beam center relative to the beam pipe. Many of the scientific issues associated with ion beams of high perveance and large tune depression have been addressed over the last two decades on scaled experiments at Lawrence Berkeley and Lawrence Livermore National Laboratories, the University of Maryland, and elsewhere. The additional requirement of high space charge potential (or equivalently high line charge density) gives rise to effects (particularly the role of electrons in beam transport) which must be understood before proceeding to a large scale accelerator. The first phase of a new series of experiments in Heavy Ion Fusion Virtual National Laboratory (HIF VNL), the High Current Experiments (HCX), is now being constructed at LBNL. The mission of the HCX will be to transport beams with driver line charge density so as to investigate the physics of this regime, including constraints on the maximum radial filling factor of the beam through the pipe. This factor is important for determining both cost and reliability of a driver scale accelerator. The HCX will provide data for design of the next steps in the sequence of experiments leading to an inertial Fusion energy power plant. The focus of the program after the HCX will be on integration of all of the manipulations required for a driver. In the near term following HCX, an Integrated Beam Experiment (IBX) of the same general scale as the HCX is envisioned.

  12. MESON PRODUCTION IN RELATIVISTIC HEAVY ION COLLISIONS

    E-Print Network [OSTI]

    Schnetzer, S.R.

    2010-01-01T23:59:59.000Z

    by (kaon yield)*/*?. Fig. 27 Ion chamber voltage vs. T-Bcoincidences. Fig. ? 8 Ion chamber voltage vs. E tag29 Measured charge on the Ion chamber per beam particle vs.

  13. ELECTRON-ION RECOMBINATION OF Mg{sup 6+} FORMING Mg{sup 5+} AND OF Mg{sup 7+} FORMING Mg{sup 6+}: LABORATORY MEASUREMENTS AND THEORETICAL CALCULATIONS

    SciTech Connect (OSTI)

    Lestinsky, M.; Hahn, M.; Novotny, O.; Savin, D. W. [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Badnell, N. R. [Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Bernhardt, D.; Mueller, A.; Schippers, S. [Institut fuer Atom- und Molekuelphysik, Justus-Liebig-Universitaet Giessen, D-35392 Giessen (Germany); Bing, D.; Grieser, M.; Hoffmann, J.; Jordon-Thaden, B.; Krantz, C.; Orlov, D. A.; Repnow, R.; Shornikov, A.; Wolf, A., E-mail: m.lestinsky@gsi.de [Max-Planck-Institut fuer Kernphysik, D-69117 Heidelberg (Germany)

    2012-10-10T23:59:59.000Z

    We have measured electron-ion recombination for C-like Mg{sup 6+} forming Mg{sup 5+}, and for B-like Mg{sup 7+} forming Mg{sup 6+}. These studies were performed using a merged electron-ion beam arrangement at the TSR heavy ion storage ring located in Heidelberg, Germany. Both primary ions have metastable levels with significant lifetimes. Using a simple cascade model we estimate the population fractions in these metastable levels. For the Mg{sup 6+} results, we find that the majority of the stored ions are in a metastable level, while for Mg{sup 7+} the metastable fraction is insignificant. We present the Mg{sup 6+} merged beams recombination rate coefficient for DR via N = 2 {yields} N' = 2 core electron excitations ({Delta}N = 0 DR) and for Mg{sup 7+} via 2 {yields} 2 and 2 {yields} 3 core excitations. Taking the estimated metastable populations into account, we compare our results to state-of-the-art multiconfiguration Breit-Pauli theoretical calculations. Significant differences are found at low energies where theory is known to be unreliable. Moreover, for both ions we observe a discrepancy between experiment and theory for {Delta}N = 0 DR involving capture into high-n Rydberg levels and where the stabilization is primarily due to a radiative transition of the excited core electron. This is consistent with previous DR experiments on M-shell iron ions which were performed at TSR. The large metastable content of the Mg{sup 6+} ion beam precludes generating a plasma recombination rate coefficient (PRRC). However, this is not an issue for Mg{sup 7+} and we present an experimentally derived Mg{sup 7+} PRRC for plasma temperatures from 400 K to 10{sup 7} K with an estimated uncertainty of less than 27% at a 90% confidence level. We also provide a fit to our experimentally derived PRRC for use in plasma modeling codes.

  14. THE RELATIVISTIC HEAVY ION COLLIDER (RHIC) REFRIGERATOR SYSTEM AT BROOKHAVEN NATIONAL LABORATORY: PHASE III OF THE SYSTEM PERFORMANCE AND OPERATIONS UPGRADES FOR 2003

    SciTech Connect (OSTI)

    SIDI-YEKHLEF,A.; TUOZZOLO,J.; THAN, R.; KNUDSEN, P.; ARENIUS, D.

    2005-08-29T23:59:59.000Z

    An ongoing program at Brookhaven National Laboratory (BNL) consists of improving the efficiency of the Relativistic Heavy Ion Collider (RHIC) cryogenic system and reducing its power consumption. Phase I and I1 of the program addressed plant operational improvements and modifications that resulted in substantial operational cost reduction and improved system reliability and stability, and a compressor input power reduction of 2 MW has been demonstrated. Phase 111, now under way, consists of plans for further increasing the efficiency of the plant by adding a load ''wet'' turbo-expander and its associated heat exchangers at the low temperature end of the plant. This additional stage of cooling at the coldest level will further reduce the required compressor flow and therefore compressor power input. This paper presents the results of the plant characterization, as it is operating presently, as well as the results of the plant simulations of the various planned upgrades for, the plant. The immediate upgrade includes the changes associated with the load expander. The subsequent upgrade will involve the resizing of expander 5 and 6 to increase their efficiencies. The paper summarizes the expected improvement in the plant efficiency and the overall reduction in the compressor power.

  15. The Relativistic Heavy Ion Collider (RHIC) Refrigerator System at Brookhaven National Laboratory: Phase III of the System Performance and Operations Upgrades for 2006

    SciTech Connect (OSTI)

    A. Sidi-Yekhlef; R. Than; J. Tuozzolo; V. Ganni; P. Knudsen; D. Arenius

    2006-05-01T23:59:59.000Z

    An ongoing program at Brookhaven National Laboratory (BNL) consists of improving the efficiency of the Relativistic Heavy Ion Collider (RHIC) cryogenic system and reducing its power consumption. Phase I and II of the program addressed plant operational improvements and modifications that resulted in substantial operational cost reduction and improved system reliability and stability, and a compressor input power reduction of 2 MW has been demonstrated. Phase III, now under way, consists of plans for further increasing the efficiency of the plant by adding a load ''wet'' turbo-expander and its associated heat exchangers at the low temperature end of the plant. This additional stage of cooling at the coldest level will further reduce the required compressor flow and therefore compressor power input. This paper presents the results of the plant characterization, as it is operating presently, as well as the results of the plant simulations of the various planned upgrades for the plant. The immediate upgrade includes the changes associated with the load expander. The subsequent upgrade will involve the resizing of expander 5 and 6 to increase their efficiencies. The paper summarizes the expected improvement in the plant efficiency and the overall reduction in the compressor power.

  16. The high current transport experiment for heavy ion inertial fusion

    SciTech Connect (OSTI)

    Prost, L.R.; Baca, D.; Bieniosek, F.M.; Celata, C.M.; Faltens, A.; Henestroza, E.; Kwan, J.W.; Leitner, M.; Seidl, P.A.; Waldron, W.L.; Cohen, R.; Friedman, A.; Grote, D.; Lund, S.M.; Molvik, A.W.; Morse, E.

    2004-05-01T23:59:59.000Z

    The High Current Experiment (HCX) at Lawrence Berkeley National Laboratory is part of the US program to explore heavy-ion beam transport at a scale representative of the low-energy end of an induction linac driver for fusion energy production. The primary mission of this experiment is to investigate aperture fill factors acceptable for the transport of space-charge-dominated heavy-ion beams at high intensity (line charge density {approx} 0.2 {micro}C/m) over long pulse durations (4 {micro}s) in alternating gradient focusing lattices of electrostatic or magnetic quadrupoles. This experiment is testing transport issues resulting from nonlinear space-charge effects and collective modes, beam centroid alignment and steering, envelope matching, image charges and focusing field nonlinearities, halo and, electron and gas cloud effects. We present the results for a coasting 1 MeV K{sup +} ion beam transported through ten electrostatic quadrupoles. The measurements cover two different fill factor studies (60% and 80% of the clear aperture radius) for which the transverse phase-space of the beam was characterized in detail, along with beam energy measurements and the first halo measurements. Electrostatic quadrupole transport at high beam fill factor ({approx}80%) is achieved with acceptable emittance growth and beam loss, even though the initial beam distribution is not ideal (but the emittance is low) nor in thermal equilibrium. We achieved good envelope control, and rematching may only be needed every ten lattice periods (at 80% fill factor) in a longer lattice of similar design. We also show that understanding and controlling the time dependence of the envelope parameters is critical to achieving high fill factors, notably because of the injector and matching section dynamics.

  17. Berkeley Accelerator Space Effects (BASE) Light Ion Facility Upgrade

    E-Print Network [OSTI]

    Johnson, Michael B.; McMahan, Margaret A.; Gimpel, Thomas L.; Tiffany, William S.

    2006-01-01T23:59:59.000Z

    a position- sensitive ion chamber for online dosimetry, theBeam Exit Window The ion chamber (Fig. 3) monitors the beamthe nitrogen-filled ion chamber leave a trail of ions that

  18. On compensating tune spread induced by space charge in bunched beams

    SciTech Connect (OSTI)

    Litvinenko, V. N.; Wang, G.

    2014-05-09T23:59:59.000Z

    Space charge effects play significant role in modern-day accelerators. These effects frequently constrain attainable beam parameters in an accelerator, or, in an accelerator chain. They also could limit the luminosity of hadron colliders operating either at low energies or with a sub-TeV high brightness hadron beams. The latter is applied for strongly cooled proton and ion beams in eRHIC – the proposed future electron-ion collider at Brookhaven National Laboratory. A number of schemes for compensating space charge effects in a coasting (e.g. continuous) hadron beam were proposed and some of them had been tested. Using a proper transverse profile of the electron beam (or plasma column) for a coasting beam would compensate both the tune shift and the tune spread in the hadron beam. But all of these methods do not address the issue of tune spread compensation of a bunched hadron beam, e.g. the tune shift dependence on the longitudinal position inside the bunch. In this paper we propose and evaluate a novel idea of using a co-propagating electron bunch with miss-matched longitudinal velocity to compensate the space charge induced tune-shift and tune spread. We present a number of practical examples of such system.

  19. Laboratory Directed Research and Development Program FY 2010

    E-Print Network [OSTI]

    Hansen, Todd

    2011-01-01T23:59:59.000Z

    blanket designs using depleted uranium were found to attainblanket fueled with depleted uranium and a heavy- ion beam

  20. Nanofabrication using focused ion beam

    E-Print Network [OSTI]

    Latif, Adnan

    College and Department of Materials Science and Metallurgy for the financial help, which made this project possible. I would also like to thank Mr. Peter Martin for the internship with SEMIKRON. Lastly, I will like to thank my family, my friends... , Sens. Actuators A 55, 19 (1996). 22. G. Ensell, J. Micromech. Microeng. 5, 1 (1995). 23. D. F. Moore, M. I. Lutwyche, N. Fujimaki, and K Gotoh, Superconductor Sci. Tech. 4, 401 (1991) 24. H. Fujita, Sens. Actuators A 56, 105 (1996). 25. M. Bao and W...

  1. Beam commissioning results for the RFQ and MEBT of the EBIS based preinjector for RHIC

    SciTech Connect (OSTI)

    Okamura, M.; Alessi, J.; Beebe, E.; Kondo, K.; Lambiase, R.; Lockey, R.; LoDestro, V.; Mapes, M.; McNerney, A.; Phillips, D.; Pikin, A.I.; Raparia, D.; Ritter, J.; Smart, L.; Snydstrup, L.; Zaltsman, A.; Tamura, J.; Schempp, A.; Zhang, C.; Schmidt, J.S.; Vossberg, M.; Kanesue, T.

    2010-09-12T23:59:59.000Z

    The EBIS based preinjector for both the Relativistic Heavy Ion Collider (RHIC) and NASA Space Radiation Laboratory (NSRL) is now being commissioned at Brookhaven National Laboratory (BNL). In 2008, the RFQ for the project was delivered and commissioned using Test EBIS, which was built to demonstrate the high current EBIS's performance. A dedicated beamline after the RFQ was assembled to confirm the RFQ's performance, and the beam energy was measured by a bending dipole magnet. In November 2009, the RFQ was moved to the final location and the vanes were realigned. The beam commissioning with the RHIC-EBIS was started again during March 2010. The RFQ accelerates ions from 17 keV/u to 300 keV/u and operates at 100.625 MHz. It is followed by a short Medium Energy Beam Transport (MEBT), which consists of four quadrupoles and one buncher cavity. Some temporary diagnostics for this commissioning include an emittance probe, TOF system, fast Faraday cup, and beam current measurement units. As of September 2010, the RFQ and the MEBT show expected performance with He{sup +}, Au{sup 32+} and Fe{sup 20+} beams. Further commissioning for higher intensity beams is in progress.

  2. Metallic beam development for the Facility for Rare Isotope Beam

    SciTech Connect (OSTI)

    Machicoane, Guillaume, E-mail: machicoa@nscl.msu.edu; Cole, Dallas; Leitner, Daniela; Neben, Derek; Tobos, Larry [Facility for Rare Isotope Beam, Michigan State University, East Lansing, Michigan 48824 (United States)] [Facility for Rare Isotope Beam, Michigan State University, East Lansing, Michigan 48824 (United States)

    2014-02-15T23:59:59.000Z

    The Facility for Rare Isotope Beams (FRIB) at Michigan State University (MSU) will accelerate a primary ion beam to energies beyond 200 MeV/u using a superconducting RF linac and will reach a maximum beam power of 400 kW on the fragmentation target. The beam intensity needed from the ECR ion source is expected to be between 0.4 and 0.5 emA for most medium mass to heavy mass elements. Adding to the challenge of reaching the required intensity, an expanded list of primary beams of interest has been established based on the production rate and the number of isotope beams that could be produced with FRIB. We report here on the development done for some of the beam in the list including mercury (natural), molybdenum ({sup 98}Mo), and selenium ({sup 82}Ser)

  3. Heavy Ion Fusion Science Virtual National Laboratory 4th Quarter 2009 Milestone Report: Measure and simulate target temperature and dynamic response in optimized NDCX-I configurations with initial diagnostics suite

    SciTech Connect (OSTI)

    Bieniosek, F.M.; Barnard, J.J.; Henestroza, E.; Logan, B.G.; Lidia, S.; More, R.M.; Ni, P.A.; Seidl, P.A.; Vay, J.-L.; Grote, D.; Friedman, A.

    2009-09-30T23:59:59.000Z

    This milestone has been met. The effort contains two main components: (1) Experimental results of warm dense matter target experiments on optimized NDCX-I configurations that include measurements of target temperature and transient target behavior. (2) A theoretical model of the target response to beam heating that includes an equilibrium heating model of the target foil and a model for droplet formation in the target for comparison with experimental results. The experiments on ion-beam target heating use a 300-350-keV K{sup +} pulsed beam from the Neutralized Compression Drift Experiment (NDCX-I) accelerator at LBNL. The NDCX-I accelerator delivers an uncompressed pulse beam of several microseconds with a typical power density of >100 kW/cm{sup 2} over a final focus spot size of about 1 mm. An induction bunching module the NDCX-I compresses a portion of the beam pulse to reach a much higher power density over 2 nanoseconds. Under these conditions the free-standing foil targets are rapidly heated to temperatures to over 4000 K. We model the target thermal dynamics using the equation of heat conduction for the temperature T(x,t) as a function of time (t) and spatial dimension along the beam direction (x). The competing cooling processes release energy from the surface of the foil due to evaporation, radiation, and thermionic (Richardson) emission. A description of the experimental configuration of the target chamber and results from initial beam-target experiments are reported in our FY08 4th Quarter and FY09 2nd Quarter Milestone Reports. The WDM target diagnostics include a high-speed multichannel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. The fast optical pyrometer is a unique and significant new diagnostic which provides valuable information on the temperature evolution of the heated target.

  4. Characterization of an iodine-based ionic liquid ion source and studies on ion fragmentation

    E-Print Network [OSTI]

    Fedkiw, Timothy Peter

    2010-01-01T23:59:59.000Z

    Electrosprays are a well studied source of charged droplets and ions. A specific subclass is the ionic liquid ion source (ILIS), which produce ion beams from the electrostatically stressed meniscus of ionic liquids. ILIS ...

  5. Respiratory motion management using audio-visual biofeedback for respiratory-gated radiotherapy of synchrotron-based pulsed heavy-ion beam delivery

    SciTech Connect (OSTI)

    He, Pengbo; Ma, Yuanyuan; Huang, Qiyan; Yan, Yuanlin [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000 (China); School of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049 (China); Li, Qiang, E-mail: liqiang@impcas.ac.cn; Liu, Xinguo; Dai, Zhongying; Zhao, Ting; Fu, Tingyan; Shen, Guosheng [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000 (China)

    2014-11-01T23:59:59.000Z

    Purpose: To efficiently deliver respiratory-gated radiation during synchrotron-based pulsed heavy-ion radiotherapy, a novel respiratory guidance method combining a personalized audio-visual biofeedback (BFB) system, breath hold (BH), and synchrotron-based gating was designed to help patients synchronize their respiratory patterns with synchrotron pulses and to overcome typical limitations such as low efficiency, residual motion, and discomfort. Methods: In-house software was developed to acquire body surface marker positions and display BFB, gating signals, and real-time beam profiles on a LED screen. Patients were prompted to perform short BHs or short deep breath holds (SDBH) with the aid of BFB following a personalized standard BH/SDBH (stBH/stSDBH) guiding curve or their own representative BH/SDBH (reBH/reSDBH) guiding curve. A practical simulation was performed for a group of 15 volunteers to evaluate the feasibility and effectiveness of this method. Effective dose rates (EDRs), mean absolute errors between the guiding curves and the measured curves, and mean absolute deviations of the measured curves were obtained within 10%–50% duty cycles (DCs) that were synchronized with the synchrotron’s flat-top phase. Results: All maneuvers for an individual volunteer took approximately half an hour, and no one experienced discomfort during the maneuvers. Using the respiratory guidance methods, the magnitude of residual motion was almost ten times less than during nongated irradiation, and increases in the average effective dose rate by factors of 2.39–4.65, 2.39–4.59, 1.73–3.50, and 1.73–3.55 for the stBH, reBH, stSDBH, and reSDBH guiding maneuvers, respectively, were observed in contrast with conventional free breathing-based gated irradiation, depending on the respiratory-gated duty cycle settings. Conclusions: The proposed respiratory guidance method with personalized BFB was confirmed to be feasible in a group of volunteers. Increased effective dose rate and improved overall treatment precision were observed compared to conventional free breathing-based, respiratory-gated irradiation. Because breathing guidance curves could be established based on the respective average respiratory period and amplitude for each patient, it may be easier for patients to cooperate using this technique.

  6. HEAVY ION INERTIAL FUSION

    E-Print Network [OSTI]

    Keefe, D.

    2008-01-01T23:59:59.000Z

    Accelerators as Drivers for Inertially Confined Fusion, W.B.LBL-9332/SLAC-22l (1979) Fusion Driven by Heavy Ion Beams,OF CALIFORNIA f Accelerator & Fusion Research Division

  7. Progress in Beam Focusing and Compression for Target Heating and Warm Dense Matter Experiments

    SciTech Connect (OSTI)

    Seidl, Peter; Anders, A.; Bieniosek, F.M.; Barnard, J.J.; Cohen, R.H.; Coleman, J.E.; Dorf, M.; Gilson, E.P.; Grote, D.P.; Jung, J.Y.; Leitner, M.; Lidia, S.M.; Logan, B.G.; Ni, P.; Roy, P.A.; Waldron, W.L.; Welch, D.R.

    2009-04-17T23:59:59.000Z

    The Heavy-Ion Fusion Sciences Virtual National Laboratory is pursuing an approach to target heating experiments in the warm dense matter regime, using space-charge-dominated ion beams that are simultaneously longitudinally bunched and transversely focused. Longitudinal beam compression by large factors has been demonstrated in the Neutralized Drift Compression Experiment (NDCX) with controlled ramps and forced neutralization. Using an injected 30 mA K{sup +} ion beam with initial kinetic energy 0.3 MeV, axial compression leading to {approx}50X current amplification and simultaneous radial focusing to a few mm have led to encouraging energy deposition approaching the intensities required for eV-range target heating experiments. We discuss the status of several improvements to NDCX to reach the necessary higher beam intensities, including: beam diagnostics, greater axial compression via a longer velocity ramp; and plasma injection improvements to establish a plasma density always greater than the beam density, expected to be > 10{sup 13} cm{sup -3}.

  8. Parametic Study of the current limit within a single driver-scale transport beam line of an induction Linac for Heavy Ion Fusion

    E-Print Network [OSTI]

    Prost, Lionel Robert

    2007-01-01T23:59:59.000Z

    to controlled thermonuclear fusion which uses intense ion orto controlled thermonuclear fusion energy to commercialFusion Energy (MFE) is the approach to controlled thermonuclear

  9. Secondary ion collection and transport system for ion microprobe

    DOE Patents [OSTI]

    Ward, James W. (Canoga Park, CA); Schlanger, Herbert (Simi Valley, CA); McNulty, Jr., Hugh (Santa Monica, CA); Parker, Norman W. (Camarillo, CA)

    1985-01-01T23:59:59.000Z

    A secondary ion collection and transport system, for use with an ion microprobe, which is very compact and occupies only a small working distance, thereby enabling the primary ion beam to have a short focal length and high resolution. Ions sputtered from the target surface by the primary beam's impact are collected between two arcuate members having radii of curvature and applied voltages that cause only ions within a specified energy band to be collected. The collected ions are accelerated and focused in a transport section consisting of a plurality of spaced conductive members which are coaxial with and distributed along the desired ion path. Relatively high voltages are applied to alternate transport sections to produce accelerating electric fields sufficient to transport the ions through the section to an ion mass analyzer, while lower voltages are applied to the other transport sections to focus the ions and bring their velocity to a level compatible with the analyzing apparatus.

  10. Monte Carlo beam capture and charge breeding simulation

    SciTech Connect (OSTI)

    Kim, J.S.; Liu, C.; Edgell, D.H.; Pardo, R. [FAR-TECH, Inc., 10350 Science Center Drive, San Diego, California 92121 (United States); FAR-TECH, Inc., 10350 Science Center Drive, San Diego, California 92121 (United States) and University of Rochester, Rochester, New York (United States); Argonne National Laboratory, Argonne, Illinois (United States)

    2006-03-15T23:59:59.000Z

    A full six-dimensional (6D) phase space Monte Carlo beam capture charge-breeding simulation code examines the beam capture processes of singly charged ion beams injected to an electron cyclotron resonance (ECR) charge breeder from entry to exit. The code traces injected beam ions in an ECR ion source (ECRIS) plasma including Coulomb collisions, ionization, and charge exchange. The background ECRIS plasma is modeled within the current frame work of the generalized ECR ion source model. A simple sample case of an oxygen background plasma with an injected Ar +1 ion beam produces lower charge breeding efficiencies than experimentally obtained. Possible reasons for discrepancies are discussed.

  11. eRHIC ring-ring design with head-on beam-beam compensation

    SciTech Connect (OSTI)

    Montag,C.; Blaskiewicz, M.; Pozdeyev, E.; Fischer, W.; MacKay, W. W.

    2009-05-04T23:59:59.000Z

    The luminosity of the eRHIC ring-ring design is limited by the beam-beam effect exerted on the electron beam. Recent simulation studies have shown that the beam-beam limit can be increased by means of an electron lens that compensates the beam-beam effect experienced by the electron beam. This scheme requires proper design of the electron ring, providing the correct betatron phase advance between interaction point and electron lens. We review the performance of the eRHIC ring-ring version and discuss various parameter sets, based on different cooling schemes for the proton/ion beam.

  12. JOURNAL DE PHYSIQUE CoZZoque C7, suppte'ment au n07, Tome 40, JuiZZet 1979, page C7-477 THE RF-ION SOURCE RIG 10FOR INTENSEHYDROGEN ION BEAMS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    - are accelerated,too, by the s w mechanism. We obtain an intense electrodeless, non-them1 rf-plasma. The ham- advantages of our rf-plasma source called RIG 10 (-Radio-Frequency- Ion-erator of 10 an in diameter): This type of ion- source has no discharge electrodes immersed in the discharge plasma

  13. Final Report Independent Verification Survey of the High Flux Beam Reactor, Building 802 Fan House Brookhaven National Laboratory Upton, New York

    SciTech Connect (OSTI)

    Evan Harpeneau

    2011-06-24T23:59:59.000Z

    The Separations Process Research Unit (SPRU) complex located on the Knolls Atomic Power Laboratory (KAPL) site in Niskayuna, New York, was constructed in the late 1940s to research the chemical separation of plutonium and uranium (Figure A-1). SPRU operated as a laboratory scale research facility between February 1950 and October 1953. The research activities ceased following the successful development of the reduction oxidation and plutonium/uranium extraction processes. The oxidation and extraction processes were subsequently developed for large scale use by the Hanford and Savannah River sites (aRc 2008a). Decommissioning of the SPRU facilities began in October 1953 and continued through the 1990s.

  14. Final Report Independent Verification Survey of the High Flux Beam Reactor, Building 802 Fan House Brookhaven National Laboratory Upton, New York

    SciTech Connect (OSTI)

    Harpeneau, Evan M. [Oak Ridge Institute for Science and Education, Oak Ridge, TN (United States). Independent Environmental Assessment and Verification Program

    2011-06-24T23:59:59.000Z

    On May 9, 2011, ORISE conducted verification survey activities including scans, sampling, and the collection of smears of the remaining soils and off-gas pipe associated with the 802 Fan House within the HFBR (High Flux Beam Reactor) Complex at BNL. ORISE is of the opinion, based on independent scan and sample results obtained during verification activities at the HFBR 802 Fan House, that the FSS (final status survey) unit meets the applicable site cleanup objectives established for as left radiological conditions.

  15. Test of electron beam technology on Savannah River Laboratory low-activity aqueous waste for destruction of benzene, benzene derivatives, and bacteria

    SciTech Connect (OSTI)

    Dougal, R.A. [Univ. of South Carolina, Columbia, SC (United States). Dept. of Electrical and Computer Engineering

    1993-08-01T23:59:59.000Z

    High energy radiation was studied as a means for destroying hazardous organic chemical wastes. Tests were conducted at bench scale with a {sup 60}Co source, and at full scale (387 l/min) with a 1.5 MV electron beam source. Bench scale tests for both benzene and phenol included 32 permutations of water quality factors. For some water qualities, as much as 99.99% of benzene or 90% of phenol were removed by 775 krads of {sup 60}Co irradiation. Full scale testing for destruction of benzene in a simulated waste-water mix showed loss of 97% of benzene following an 800 krad dose and 88% following a 500 krad dose. At these loss rates, approximately 5 Mrad of electron beam irradiation is required to reduce concentrations from 100 g/l to drinking water quality (5 {mu}g/l). Since many waste streams are also inhabited by bacterial populations which may affect filtering operations, the effect of irradiation on those populations was also studied. {sup 60}Co and electron beam irradiation were both lethal to the bacteria studied at irradiation levels far lower than were necessary to remove organic contaminants.

  16. Bunch length effects in the beam-beam compensation with an electron lens

    SciTech Connect (OSTI)

    Fischer, W.; Luo, Y.; Montag, C.

    2010-02-25T23:59:59.000Z

    Electron lenses for the head-on beam-beam compensation are under construction at the Relativistic Heavy Ion Collider. The bunch length is of the same order as the {beta}-function at the interaction point, and a proton passing through another proton bunch experiences a substantial phase shift which modifies the beam-beam interaction. We review the effect of the bunch length in the single pass beam-beam interaction, apply the same analysis to a proton passing through a long electron lens, and study the single pass beam-beam compensation with long bunches. We also discuss the beam-beam compensation of the electron beam in an electron-ion collider ring.

  17. A relation between surface oxide and oxygen-defect complexes in solid-phase epitaxial Si regrown from ion-beam-amorphized Si layers

    SciTech Connect (OSTI)

    Petkov, Mihail P. [Department of Physics, Washington State University, Pullman, Washington 99163-2814 (United States)] [Department of Physics, Washington State University, Pullman, Washington 99163-2814 (United States); Chen, Claudine M. [Thomas J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, California 91125 (United States)] [Thomas J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, California 91125 (United States); Atwater, Harry A. [Thomas J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, California 91125 (United States)] [Thomas J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, California 91125 (United States); Rassiga, Stefano [Department of Physics, Washington State University, Pullman, Washington 99163-2814 (United States)] [Department of Physics, Washington State University, Pullman, Washington 99163-2814 (United States); Lynn, Kelvin G. [Department of Physics, Washington State University, Pullman, Washington 99163-2814 (United States)] [Department of Physics, Washington State University, Pullman, Washington 99163-2814 (United States)

    2000-03-13T23:59:59.000Z

    We present a direct evidence that ion implantation through thin ({<=}5 nm) surface oxide layers is a source of O impurities, which form O-defect complexes during thermal treatment. The impurity-defect complexes are identified by correlating the results from positron annihilation spectroscopy, secondary-ion mass spectroscopy, and Monte Carlo simulations. The O atoms are introduced in the bulk by multiple recoil implantation by the primary ions. The signatures of large V{sub m}O{sub n} formations are observed at 800 degree sign C, which implies the existence of smaller species at lower temperatures. (c) 2000 American Institute of Physics.

  18. RHIC | Relativistic Heavy Ion Collider

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Photo of LINAC The Relativistic Heavy Ion Collider (RHIC) is a world-class particle accelerator at Brookhaven National Laboratory where physicists are exploring the most...

  19. Characterization of an RF plasma ion source for ion implantation

    SciTech Connect (OSTI)

    Kopalidis, Peter M.; Wan Zhimin [Advanced Ion Beam Technology Inc., 47370 Fremont Blvd., Fremont, CA 94538 (United States)

    2012-11-06T23:59:59.000Z

    A novel inductively coupled RF plasma ion source has been developed for use in a beamline ion implanter. Ion density data have been taken with an array of four Langmuir probes spaced equally at the source extraction arc slit. These provide ion density uniformity information as a function of source pressure, RF power and gas mixture composition. In addition, total extracted ion beam current data are presented for the same conditions. The comparative advantages of the RF source in terms of higher beam current, reduced maintenance and overall productivity improvement compared to a hot cathode source are discussed.

  20. Simulating Electron Clouds in Heavy-Ion Accelerators

    SciTech Connect (OSTI)

    Cohen, R.H.; Friedman, A.; Kireeff Covo, M.; Lund, S.M.; Molvik,A.W.; Bieniosek, F.M.; Seidl, P.A.; Vay, J-L.; Stoltz, P.; Veitzer, S.

    2005-04-07T23:59:59.000Z

    Contaminating clouds of electrons are a concern for most accelerators of positive-charged particles, but there are some unique aspects of heavy-ion accelerators for fusion and high-energy density physics which make modeling such clouds especially challenging. In particular, self-consistent electron and ion simulation is required, including a particle advance scheme which can follow electrons in regions where electrons are strongly-, weakly-, and un-magnetized. They describe their approach to such self-consistency, and in particular a scheme for interpolating between full-orbit (Boris) and drift-kinetic particle pushes that enables electron time steps long compared to the typical gyro period in the magnets. They present tests and applications: simulation of electron clouds produced by three different kinds of sources indicates the sensitivity of the cloud shape to the nature of the source; first-of-a-kind self-consistent simulation of electron-cloud experiments on the High-Current Experiment (HCX) at Lawrence Berkeley National Laboratory, in which the machine can be flooded with electrons released by impact of the ion beam and an end plate, demonstrate the ability to reproduce key features of the ion-beam phase space; and simulation of a two-stream instability of thin beams in a magnetic field demonstrates the ability of the large-timestep mover to accurately calculate the instability.