National Library of Energy BETA

Sample records for focused ion beam

  1. Focused ion beam system

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA); Gough, Richard A. (Kensington, CA); Ji, Qing (Berkeley, CA); Lee, Yung-Hee Yvette (Berkeley, CA)

    1999-01-01

    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 .mu.m or less.

  2. Focused ion beam system

    DOE Patents [OSTI]

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

    1999-08-31

    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.

  3. Nanofabrication using focused ion beam

    E-Print Network [OSTI]

    Latif, Adnan

    Focused ion beam (FIB) technique uses a focused beam of ions to scan the surface of a specimen, analogous to the way scanning electron microscope (SEM) utilizes electrons. Recent developments in the FIB technology have led to beam spot size below...

  4. Focused electron and ion beam systems

    DOE Patents [OSTI]

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

    2004-07-27

    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.

  5. 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)

    2000-01-01

    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.

  6. Focused ion beam micromilling and articles therefrom

    DOE Patents [OSTI]

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

    1998-01-01

    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.

  7. Focused ion beam micromilling and articles therefrom

    DOE Patents [OSTI]

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

    1998-06-30

    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. Development of a focused ion beam micromachining system

    SciTech Connect (OSTI)

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

    1988-12-01

    Focused ion beams are currently being investigated for many submicron fabrication and analytical purposes. An FIB micromachining system consisting of a UHV vacuum system, a liquid metal ion gun, and a control and data acquisition computer has been constructed. This system is being used to develop nanofabrication and nanomachining techniques involving focused ion beams and scanning tunneling microscopes.

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

    E-Print Network [OSTI]

    Perez Martinez, Carla S. (Carla Sofia)

    2013-01-01

    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 ...

  10. Ultrahigh vacuum focused ion beam micromill and articles therefrom

    DOE Patents [OSTI]

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

    1998-02-24

    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.

  11. Ultrahigh vacuum focused ion beam micromill and articles therefrom

    DOE Patents [OSTI]

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

    1998-01-01

    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.

  12. Effect of beam limiting aperture and collector potential on multi-element focused ion beams

    SciTech Connect (OSTI)

    Paul, Samit; Chowdhury, Abhishek; Bhattacharjee, Sudeep [Department of Physics, Indian Institute of Technology, Kanpur, Uttar Pradesh (India)

    2012-02-15

    A compact microwave driven plasma based multi-element focused ion beam system has been developed. In the present work, the effect of reduced beam limiter (BL) aperture on the focused ion beam parameters, such as current and spot size, and a method of controlling beam energy independently by introducing a biased collector at focal point (FP) are investigated. It is found that the location of FP does not change due to the reduction of BL aperture. The location of FP and beam size are found to be weakly dependent on the collector potential in the range from -8 kV to -18 kV.

  13. Laser-Cooled Lithium Atoms: A New Source for Focused Ion Beams

    E-Print Network [OSTI]

    Laser-Cooled Lithium Atoms: A New Source for Focused Ion Beams P R O J E C T L E A D E R : Jabez Mc E N T S Designed and constructed a laser-cooled, magneto-optical trap-based lithium ion source mounted on a commercial focused ion beam system, creating the world's first lithium ion microscope

  14. Production of various species of focused ion beam and T.-J. King

    E-Print Network [OSTI]

    Production of various species of focused ion beam Q. Jia) and T.-J. King Lawrence Berkeley National. It is shown that over 90% P ions are produced. The production of BF2 and O2 increases with increasing gas devices, particle accelerators, ion implan- tation systems, neutron tubes for oil well logging and proton

  15. Diagnostics of ion beam generated from a Mather type plasma focus device

    SciTech Connect (OSTI)

    Lim, L. K. Ngoi, S. K. Wong, C. S. Yap, S. L.

    2014-03-05

    Diagnostics of ion beam emission from a 3 kJ Mather-type plasma focus device have been performed for deuterium discharge at low pressure regime. Deuterium plasma focus was found to be optimum at pressure of 0.2 mbar. The energy spectrum and total number of ions per shot from the pulsed ion beam are determined by using biased ion collectors, Faraday cup, and solid state nuclear track detector CR-39. Average energy of the ion beam obtained is about 60 keV. Total number of the ions has been determined to be in the order of 10{sup 11} per shot. Solid state nuclear track detectors (SSNTD) CR39 are employed to measure the particles at all angular direction from end on (0°) to side on (90°). Particle tracks are registered by SSNTD at 30° to 90°, except the one at the end-on 0°.

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

    SciTech Connect (OSTI)

    Saraf, Laxmikant V.; Britt, David W.

    2011-09-14

    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.

  17. 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)

    2013-06-15

    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.

  18. 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.

    1999-11-05

    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.

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

    SciTech Connect (OSTI)

    Misra, Shikha; Sodha, M. S.; Mishra, S. K.

    2013-10-15

    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.

  20. Investigation of Tibetian Plateau Varnish: New Findings at the Nanoscale Using Focused Ion Beam and Transmission Electron

    E-Print Network [OSTI]

    Dorn, Ron

    electron microscopy (HR-TEM) was used. Preparing HR-TEM samples with a dual-beam fo- cused ion beamInvestigation of Tibetian Plateau Varnish: New Findings at the Nanoscale Using Focused Ion Beam and Transmission Electron Microscopy Techniques KURT A. LANGWORTHY 1 , DAVID H. KRINSLEY 2 , AND RONALD I. DORN 3 1

  1. 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)

    2014-04-28

    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.

  2. The influence of electron irradiation on electron holography of focused ion beam milled GaAs p-n junctions

    E-Print Network [OSTI]

    Dunin-Borkowski, Rafal E.

    The influence of electron irradiation on electron holography of focused ion beam milled GaAs p beam electron diffraction CBED , a value for Vbi in the electri- cally "active" part of the specimen, United Kingdom Received 16 November 2006; accepted 10 March 2007; published online 14 May 2007 Electron

  3. 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)

    2012-05-15

    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.

  4. Implementation of focused ion beam (FIB) system in characterization of nuclear fuels and materials

    SciTech Connect (OSTI)

    A. Aitkaliyeva; J. W. Madden; B. D. Miller; J I Cole; T A Hyde

    2014-10-01

    Beginning in 2007, a program was established at the Idaho National Laboratory to update key capabilities enabling microstructural and micro-chemical characterization of highly irradiated and/or radiologically contaminated nuclear fuels and materials at scales that previously had not been achieved for these types of materials. Such materials typically cannot be contact handled and pose unique hazards to instrument operators, facilities, and associated personnel. One of the first instruments to be acquired was a Dual Beam focused ion beam (FIB)-scanning electron microscope (SEM) to support preparation of transmission electron microscopy and atom probe tomography samples. Over the ensuing years, techniques have been developed and operational experience gained that has enabled significant advancement in the ability to characterize a variety of fuel types including metallic, ceramic, and coated particle fuels, obtaining insights into in-reactor degradation phenomena not obtainable by any other means. The following article describes insights gained, challenges encountered, and provides examples of unique results obtained in adapting Dual Beam FIB technology to nuclear fuels characterization.

  5. Design and Implementation of a Micron-Sized Electron Column Fabricated by Focused Ion Beam Milling

    E-Print Network [OSTI]

    Wicki, Flavio; Escher, Conrad; Fink, Hans-Werner

    2015-01-01

    We have designed, fabricated and tested a micron-sized electron column with an overall length of about 700 microns comprising two electron lenses; a micro-lens with a minimal bore of 1 micron followed by a second lens with a bore of up to 50 microns in diameter to shape a coherent low-energy electron wave front. The design criteria follow the notion of scaling down source size, lens-dimensions and kinetic electron energy for minimizing spherical aberrations to ensure a parallel coherent electron wave front. All lens apertures have been milled employing a focused ion beam and could thus be precisely aligned within a tolerance of about 300 nm from the optical axis. Experimentally, the final column shapes a quasi-planar wave front with a minimal full divergence angle of 4 mrad and electron energies as low as 100 eV.

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

    E-Print Network [OSTI]

    Henestroza, Enrique

    2006-01-01

    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 ...

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

    SciTech Connect (OSTI)

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

    2010-04-30

    Laboratory high energy density experiments using ion beam drivers rely upon the delivery of high-current, high-brightness ion beams with high peak intensity onto targets. Solid-state scintillators are typically used to measure the ion beam spatial profile but they display dose-dependent degradation and aging effects. These effects produce uncertainties and limit the accuracy of measuring peak beam intensities delivered to the target. For beam tuning and characterizing the incident beam intensity, we have developed a cross-calibrating diagnostic suite that extends the upper limit of measurable peak intensity dynamic range. Absolute intensity calibration is obtained with a 3 {micro}m thick tungsten foil calorimeter and streak spectrometer. We present experimental evidence for peak intensity measures in excess of 400 kW/cm{sup 2} using a 0.3 MV, 25 mA, 5-20 {micro}sec K{sup +1} beam. Radiative models and thermal diffusion effects are discussed because they affect temporal and spatial resolution of beam intensity profiles.

  8. Traverse Focusing of Intense Charged Particle Beams with Chromatic Effects for Heavy Ion Fusion

    SciTech Connect (OSTI)

    James M. Mitrani, Igor D. Kaganovich, Ronald C. Davidson

    2013-01-28

    A fi nal focusing scheme designed to minimize chromatic effects is discussed. The Neutralized Drift Compression Experiment-II (NDCX-II) will apply a velocity tilt for longitudinal bunch compression, and a fi nal focusing solenoid (FFS) for transverse bunch compression. In the beam frame, neutralized drift compression causes a suffi#14;ciently large spread in axial momentum, pz , resulting in chromatic effects to the fi nal focal spot during transverse bunch compression. Placing a weaker solenoid upstream of a stronger fi nal focusing solenoid (FFS) mitigates chromatic effects and improves transverse focusing by a factor of approximately 2-4 for appropriate NDCX-II parameters.

  9. Focused-ion-beam induced damage in thin films of complex oxide BiFeO{sub 3}

    SciTech Connect (OSTI)

    Siemons, W.; Beekman, C.; Budai, J. D.; Christen, H. M.; Fowlkes, J. D.; Balke, N.; Tischler, J. Z.; Xu, R.; Liu, W.; Gonzales, C. M.

    2014-02-01

    An unexpected, strong deterioration of crystal quality is observed in epitaxial perovskite BiFeO{sub 3} films in which microscale features have been patterned by focused-ion-beam (FIB) milling. Specifically, synchrotron x-ray microdiffraction shows that the damaged region extends to tens of ?m, but does not result in measureable changes to morphology or stoichiometry. Therefore, this change would go undetected with standard laboratory equipment, but can significantly influence local material properties and must be taken into account when using a FIB to manufacture nanostructures. The damage is significantly reduced when a thin metallic layer is present on top of the film during the milling process, clearly indicating that the reduced crystallinity is caused by ion beam induced charging.

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

    E-Print Network [OSTI]

    Cincinnati, University of

    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

  11. 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. Nakamiya, A.; Sakakita, H.; Innovative Plasma Technologies Group, National Institute of Advanced Industrial Science and Technology , Ibaraki ; Hirano, Y.; Laboratory of Physics, College of Science and Technologies, Nihon University, Tokyo ; Kiyama, S.; Koguchi, H.

    2014-02-15

    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.

  12. Low-temperature charge transport in Ga-acceptor nanowires implanted by focused-ion beams

    E-Print Network [OSTI]

    Robinson, SJ

    2008-01-01

    3 ) through an 11-nm oxide layer. 10 The beam density duringemission images of the oxide layers, and they are typicallyJVD) 23 over the 11-nm oxide layer of the Ga-implanted

  13. 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

    2011-03-24

    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.

  14. Three-Dimensional Reconstruction and Microstructure Modeling of Porosity-Graded Cathode Using Focused Ion Beam and Homogenization Techniques

    SciTech Connect (OSTI)

    Hamedani, Amani; Baniassadi, Majid; Sheidaei, A.; Pourboghrat, F.; Remond, Y.; Khaleel, Mohammad A.; Garmestani, Hamid

    2014-02-28

    In this study, microstructure of a porosity-graded lanthanum strontium manganite (LSM) cathode of solid oxide fuel cells (SOFCs) has been characterized using focused ion beam (FIB) and scanning electron microscopy(SEM) combined with image processing. Two-point correlation functions of the two-dimensional (2D) images taken along the direction of porosity gradient are used to reconstruct a three-dimensional (3D) microstructure. The effective elastic modulus of the two-phase porosity-graded cathode is predicted using strong contrast (SC) and composite inclusion (CI) homogenization techniques. The effectiveness of the two methods in predicting the effective elastic properties of the porositygraded LSM cathode is investigated in comparison with the results obtained from the finite element model (FEM).

  15. 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

    2015-01-01

    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.

  16. Ion beam generating apparatus

    DOE Patents [OSTI]

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

    1987-01-01

    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.

  17. Ion beam generating apparatus

    DOE Patents [OSTI]

    Brown, I.G.; Galvin, J.

    1987-12-22

    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.

  18. Maskless, resistless ion beam lithography

    SciTech Connect (OSTI)

    Ji, Qing

    2003-03-10

    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.

  19. Pulsed ion beam source

    DOE Patents [OSTI]

    Greenly, J.B.

    1997-08-12

    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.

  20. 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)

    1993-12-31

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

  1. 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

    2013-01-21

    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.

  2. 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

    2014-02-14

    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.

  3. Highly Ordered Ga Nanodroplets on a GaAs Surface Formed by a Focused Ion Beam Qiangmin Wei,1

    E-Print Network [OSTI]

    Lu, Wei

    quantum dots by low-energy ion sputtering on a surface has been reported in several semiconductor sys quantum dots on the surface. The mechanism involves the balance between roughening and smoothing actions], Ge [10], as well as a variety of III­V compounds (GaSb [11], InP [12], and InSb [13]) can form

  4. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDid you notHeat Pumps Heat PumpsfacilityviaGasforVendors »Ion Beam

  5. Electrostatic plasma lens for focusing negatively charged particle beams

    SciTech Connect (OSTI)

    Goncharov, A. A.; Dobrovolskiy, A. M.; Dunets, S. M.; Litovko, I. V.; Gushenets, V. I.; Oks, E. M.

    2012-02-15

    We describe the current status of ongoing research and development of the electrostatic plasma lens for focusing and manipulating intense negatively charged particle beams, electrons, and negative ions. The physical principle of this kind of plasma lens is based on magnetic isolation electrons providing creation of a dynamical positive space charge cloud in shortly restricted volume propagating beam. Here, the new results of experimental investigations and computer simulations of wide-aperture, intense electron beam focusing by plasma lens with positive space charge cloud produced due to the cylindrical anode layer accelerator creating a positive ion stream towards an axis system is presented.

  6. 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))

    1989-01-01

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

  7. 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

    2007-02-01

    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.

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

    E-Print Network [OSTI]

    Kong, David Sun, 1979-

    2004-01-01

    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, ...

  9. Electron beam ion source and electron beam ion trap (invited)

    SciTech Connect (OSTI)

    Becker, Reinard [Scientific Software Service, Kapellenweg 2a, D-63571 Gelnhausen (Germany); Kester, Oliver [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States)

    2010-02-15

    The electron beam ion source (EBIS) and its trap variant [electron beam ion trap (EBIT)] celebrated their 40th and 20th anniversary, respectively, at the EBIS/T Symposium 2007 in Heidelberg. These technologically challenging sources of highly charged ions have seen a broad development in many countries over the last decades. In contrast to most other ion sources the recipe of improvement was not ''sorcery'' but a clear understanding of the physical laws and obeying the technological constraints. This review will report important achievements of the past as well as promising developments in the future.

  10. Ion beam requirements for fast ignition of inertial fusion targets

    E-Print Network [OSTI]

    Honrubia, J J

    2015-01-01

    Ion beam requirements for fast ignition are investigated by numerical simulation taking into account new effects such as ion beam divergence not included before. We assume that ions are generated by the TNSA scheme in a curved foil placed inside a re-entrant cone and focused on the cone apex or beyond. From the focusing point to the compressed core ions propagate with a given divergence angle. Ignition energies are obtained for two compressed fuel configurations heated by proton and carbon ion beams. The dependence of the ignition energies on the beam divergence angle and on the position of the ion beam focusing point have been analysed. Comparison between TNSA and quasi-monoenergetic ions is also shown.

  11. Neon Ion Beam Lithography (NIBL)

    E-Print Network [OSTI]

    Winston, Donald

    Existing techniques for electron- and ion-beam lithography, routinely employed for nanoscale device fabrication and mask/mold prototyping, do not simultaneously achieve efficient (low fluence) exposure and high resolution. ...

  12. Overview of Light-Ion Beam Therapy

    E-Print Network [OSTI]

    Chu, William T.

    2006-01-01

    measurements using various dosimeters. Discussions of theseamong ion-beam centers • Dosimeter calibrations • Do you

  13. High Power Hydrogen Injector with Beam Focusing for Plasma Heating

    SciTech Connect (OSTI)

    Deichuli, P.P.; Ivanov, A.A.; Korepanov, S.A.; Mishagin, V.V.; Sorokin, A.V.; Stupishin, N.V

    2005-01-15

    High power neutral beam injector has been developed with the atom energy of 25 keV, a current of 60 A, and several milliseconds pulse duration. Six of these injectors will be used for upgrade of the atomic injection system at central cell of a Gas Dynamic Trap (GDT) device and 2 injectors are planned for SHIP experiment.The injector ion source is based on an arc discharge plasma box. The plasma emitter is produced by a 1 kA arc discharge in hydrogen. A multipole magnetic field produced with permanent magnets at the periphery of the plasma box is used to increase its efficiency and improve homogeneity of the plasma emitter. The ion beam is extracted by a 4-electrodes ion optical system (IOS). Initial beam diameter is 200 mm. The grids of the IOS have a spherical curvature for geometrical focusing of the beam. The optimal IOS geometry and grid potentials were found with the numerical simulation to provide precise beam formation. The measured angular divergence of the beam is 0.02 rad, which corresponds to the 2.5 cm Gaussian radius of the beam profile measured at focal point.

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

    E-Print Network [OSTI]

    McDonald, Kirk

    ion to relativistic max Boosted neutrino energy spectrum: E 2Q boost 6He Beta-beam Forward focusing Target materials: Oxides Carbides Metal foils Li id t l Th Converter: Hg ~20 institutions EU suport

  15. The Low-Energy State of Circulating Stored Ion Beams: Crystalline Beams

    E-Print Network [OSTI]

    Wei, J.

    2008-01-01

    Proc. of the Workshop on Crystalline Ion Beams, Werheim,Critical Temperatures for Crystalline Beams", Proc. of theCirculating Stored Ion Beams: Crystalline Beams J. Wei, X. -

  16. Superconducting focusing quadrupoles for heavy ion fusion experiments

    SciTech Connect (OSTI)

    Sabbi, G.L.; Faltens, A.; Leitner, M.; Lietzke, A.; Seidl, P.; Barnard, J.; Lund, S.; Martovetsky, N.; Gung, C.; Minervini, J.; Radovinsky, A.; Schultz, J.; Meinke, R.

    2003-05-01

    The Heavy Ion Fusion (HIF) Program is developing superconducting focusing magnets for both near-term experiments and future driver accelerators. In particular, single bore quadrupoles have been fabricated and tested for use in the High Current Experiment (HCX) at Lawrence Berkeley National Laboratory (LBNL). The next steps involve the development of magnets for the planned Integrated Beam Experiment (IBX) and the fabrication of the first prototype multi-beam focusing arrays for fusion driver accelerators. The status of the magnet R&D program is reported, including experimental requirements, design issues and test results.

  17. Oxygen ion-beam microlithography

    DOE Patents [OSTI]

    Tsuo, Y.S.

    1991-08-20

    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.

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

    SciTech Connect (OSTI)

    Kokish, M. G.; Rajagopal, V.; Marler, J. P.; Odom, B. C.

    2014-08-15

    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.

  19. Pseudo ribbon metal ion beam source

    SciTech Connect (OSTI)

    Stepanov, Igor B. Ryabchikov, Alexander I.; Sivin, Denis O.; Verigin, Dan A.

    2014-02-15

    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.

  20. The Electron Beam Ion Source (EBIS)

    ScienceCinema (OSTI)

    Brookhaven Lab

    2010-01-08

    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

  1. LANL: Ion Beam Materials Laboratory

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

    and materials synthesis through ion implantation technology, and radiation damage stud- ies in gases, liquids, and solids. The laboratory's core is a 3.2 MV tandem ion...

  2. Measurements and simulations of focused beam for orthovoltage therapy

    SciTech Connect (OSTI)

    Abbas, Hassan; Mahato, Dip N.; Satti, Jahangir; MacDonald, C. A.

    2014-04-15

    Purpose: Megavoltage photon beams are typically used for therapy because of their skin-sparing effect. However, a focused low-energy x-ray beam would also be skin sparing, and would have a higher dose concentration at the focal spot. Such a beam can be produced with polycapillary optics. MCNP5 was used to model dose profiles for a scanned focused beam, using measured beam parameters. The potential of low energy focused x-ray beams for radiation therapy was assessed. Methods: A polycapillary optic was used to focus the x-ray beam from a tungsten source. The optic was characterized and measurements were performed at 50 kV. PMMA blocks of varying thicknesses were placed between optic and the focal spot to observe any variation in the focusing of the beam after passing through the tissue-equivalent material. The measured energy spectrum was used to model the focused beam in MCNP5. A source card (SDEF) in MCNP5 was used to simulate the converging x-ray beam. Dose calculations were performed inside a breast tissue phantom. Results: The measured focal spot size for the polycapillary optic was 0.2 mm with a depth of field of 5 mm. The measured focal spot remained unchanged through 40 mm of phantom thickness. The calculated depth dose curve inside the breast tissue showed a dose peak several centimeters below the skin with a sharp dose fall off around the focus. The percent dose falls below 10% within 5 mm of the focus. It was shown that rotating the optic during scanning would preserve the skin-sparing effect of the focused beam. Conclusions: Low energy focused x-ray beams could be used to irradiate tumors inside soft tissue within 5 cm of the surface.

  3. Flow-through ion beam source

    DOE Patents [OSTI]

    Springer, R.W.

    1997-02-11

    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.

  4. Focused electron beam in pyroelectric electron probe microanalyzer

    SciTech Connect (OSTI)

    Imashuku, Susumu; Imanishi, Akira; Kawai, Jun [Department of Materials Science and Engineering, Kyoto University, Sakyo-ku, Kyoto 606-8501 (Japan)] [Department of Materials Science and Engineering, Kyoto University, Sakyo-ku, Kyoto 606-8501 (Japan)

    2013-07-15

    We report a method to focus the electron beam generated using a pyroelectric crystal. An electron beam with a spot size of 100 ?m was achieved by applying an electrical field to an electroconductive needle tip set on a pyroelectric crystal. When the focused electron beam bombarded a sample, characteristic X-rays of the sample were only detected due to the production of an electric field between the needle tip and the sample.

  5. Thermoacoustic imaging using heavy ion beams

    SciTech Connect (OSTI)

    Claytor, T.N.; Tesmer, J.R.; Deemer, B.C.; Murphy, J.C.

    1995-10-01

    Ion beams have been used for surface modification, semiconductor device fabrication and for material analysis, which makes ion-material interactions of significant importance. Ion implantation will produce new compositions near the surface by ion mixing or directly by implanting desired ions. Ions exchange their energy to the host material as they travel into the material by several different processes. High energy ions ionize the host atoms before atomic collisions transfer the remaining momentum and stop the incident ion. As they penetrate the surface, the low energy ions ionize the host atoms, but also have a significantly large momentum transfer mechanism near the surface of the material. This leads to atoms, groups of atoms and electrons being ejected from the surface, which is the momentum transfer process of sputtering. This talk addresses the acoustic waves generated during ion implantation using modulated heavy ion beams. The mechanisms for elastic wave generation during ion implantation, in the regimes where sputtering is significant and where implantation is dominant and sputtering is negligible, has been studied. The role of momentum transfer and thermal energy production during ion implantation was compared to laser generated elastic waves in an opaque solid as a reference, since laser generated ultrasound has been extensively studied and is fairly well understood. The thermoelastic response dominated in both high and low ion energy regimes since, apparently, more energy is lost to thermal heat producing mechanisms than momentum transfer processes. The signal magnitude was found to vary almost linearly with incident energy as in the laser thermoelastic regime. The time delays for longitudinal and shear waves-were characteristic of those expected for a purely thermal heating source. The ion beams are intrinsically less sensitive to the albedo of the surface.

  6. Beam current controller for laser ion source

    DOE Patents [OSTI]

    Okamura, Masahiro

    2014-10-28

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

  7. Study on electron beam in a low energy plasma focus

    SciTech Connect (OSTI)

    Khan, Muhammad Zubair; Ling, Yap Seong; San, Wong Chiow

    2014-03-05

    Electron beam emission was investigated in a low energy plasma focus device (2.2 kJ) using copper hollow anode. Faraday cup was used to estimate the energy of the electron beam. XR100CR X-ray spectrometer was used to explore the impact of the electron beam on the target observed from top-on and side-on position. Experiments were carried out at optimized pressure of argon gas. The impact of electron beam is exceptionally notable with two different approaches using lead target inside hollow anode in our plasma focus device.

  8. 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.

    2011-03-31

    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.

  9. Computational study of ion beam extraction phenomena through multiple apertures

    SciTech Connect (OSTI)

    Hu, Wanpeng; Sang, Chaofeng; Tang, Tengfei; Wang, Dezhen, E-mail: wangdez@dlut.edu.cn [Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Li, Ming; Jin, Dazhi; Tan, Xiaohua [Institute of Electronic Engineering, Mianyang, 621900 (China)] [Institute of Electronic Engineering, Mianyang, 621900 (China)

    2014-03-15

    The process of ion extraction through multiple apertures is investigated using a two-dimensional particle-in-cell code. We consider apertures with a fixed diameter with a hydrogen plasma background, and the trajectories of electrons, H{sup +} and H{sub 2}{sup +} ions in the self-consistently calculated electric field are traced. The focus of this work is the fundamental physics of the ion extraction, and not particular to a specific device. The computed convergence and divergence of the extracted ion beam are analyzed. We find that the extracted ion flux reaching the extraction electrode is non-uniform, and the peak flux positions change according to operational parameters, and do not necessarily match the positions of the apertures in the y-direction. The profile of the ion flux reaching the electrode is mainly affected by the bias voltage and the distance between grid wall and extraction electrode.

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

    SciTech Connect (OSTI)

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

    2010-10-30

    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.

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

    DOE Patents [OSTI]

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

    2012-10-30

    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.

  12. Irradiation of Dye-Doped Microspheres with a Strongly Focused Laser Beam

    E-Print Network [OSTI]

    Zare, Richard N.

    Irradiation of Dye-Doped Microspheres with a Strongly Focused Laser Beam Results in Alignment upon Received December 12, 2001 ABSTRACT The irradiation of dye-doped polystyrene microspheres with an argon ion trap (985 nm). This behavior is well described by a model in which the differently irradiated portions

  13. 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)

    2010-11-23

    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).

  14. Physics with fast molecular-ion beams

    SciTech Connect (OSTI)

    Kanter, E.P.

    1980-01-01

    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.

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

    SciTech Connect (OSTI)

    Yuhong Zhang,Ji Qiang

    2009-05-01

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

  16. Fuel Target Implosion in Ion beam Inertial Confinement Fusion

    E-Print Network [OSTI]

    Kawata, Shigeo

    2015-01-01

    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.

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

    E-Print Network [OSTI]

    Riege, H

    2000-01-01

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

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

    DOE Patents [OSTI]

    Maschke, A.W.

    1984-04-16

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

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

    DOE Patents [OSTI]

    Maschke, Alfred W. (East Moriches, NY)

    1985-01-01

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

  20. Reflection of focused beams from opal photonic crystals

    E-Print Network [OSTI]

    Jonsson, Fredrik

    Reflection of focused beams from opal photonic crystals Karri Varis, Marco Mattila Optoelectronics from opals that are synthesized using polystyrene and poly(methyl methacrylate) microspheres. © 2005 of self-organized opal photonic crystals," Phys. Rev. E 61, 5784­5793 (2000). 12. M. Bardosova and R. H

  1. High-energy accelerator for beams of heavy ions

    DOE Patents [OSTI]

    Martin, Ronald L. (La Grange, IL); Arnold, Richard C. (Chicago, IL)

    1978-01-01

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

  2. Temporal and spatial study of neon ion emission from a plasma focus device

    SciTech Connect (OSTI)

    Bhuyan, M.; Neog, N. K.; Mohanty, S. R. [Centre of Plasma Physics, Institute for Plasma Research, Sonapur, Kamrup 782402 (India); Rao, C. V. S. [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India); Raole, P. M. [FCIPT, Institute for Plasma Research, Gandhinagar 342044 (India)

    2011-03-15

    The temporal and spatial characteristics of the neon ion beam emissions from a low energy plasma focus device have been studied by employing a multiple Faraday cup assembly and the CR-39 track detectors at different angular and axial positions. In addition, the operating gas pressures were also varied to study the temporal and spatial characteristics of the neon ion beam emissions. The Faraday cup analyses show that the ion flux strongly depends on the operating gas pressure as well as the angular positions. The estimated ion energy measurements at the aperture of the Faraday cup indicate that the plasma focus device is a source of polyenergetic ions ranging from approximately a few keV to a few hundreds of keV, irrespective of the angular positions. The exposed CR-39 detectors have shown the formation of multiple ion tracks with diameter ranging from 2 to 13 {mu}m. The populations of lower diameter tracks (2-6 {mu}m) are observed to be more at 0 deg. and 10 deg. angles. It is also noticed that the most populated track counts have shifted toward the higher diameter as the angular positions change from 0 deg. to 70 deg. The present study enables us to predict a clear picture of ion flux and energy distribution inside the plasma focus chamber that will help to use the device for material irradiation application in a more controlled manner.

  3. Electron beam ion sources and traps ,,invited... Reinard Beckera)

    E-Print Network [OSTI]

    Electron beam ion sources and traps ,,invited... Reinard Beckera) Institut fu¨r Angewandte Physik, Johann Wolfgang Goethe-Universita¨t, Frankfurt, Germany Presented on 7 September 1999 The electron beam method of stepwise ionization to highest charge states has found applications in electron beam ion

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

    DOE Patents [OSTI]

    Campbell, A.N.; Soden, J.M.

    1998-12-01

    An ion-beam apparatus and method for analyzing and controlling integrated circuits are disclosed. 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. 4 figs.

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

    DOE Patents [OSTI]

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

    1998-01-01

    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.

  6. 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))

    1989-01-01

    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.

  7. Multiple species beam production on laser ion source for electron beam ion source in Brookhaven National Laboratory

    SciTech Connect (OSTI)

    Sekine, M., E-mail: sekine.m.ae@m.titech.ac.jp [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Meguro, Tokyo (Japan); Riken, Wako, Saitama (Japan); Ikeda, S. [Riken, Wako, Saitama (Japan) [Riken, Wako, Saitama (Japan); Department of Energy Science, Tokyo Institute of Technology, Yokohama, Kanagawa (Japan); Hayashizaki, N. [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Meguro, Tokyo (Japan)] [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Meguro, Tokyo (Japan); Kanesue, T.; Okamura, M. [Collider-Accelerator Department, Brookhaven National Laboratory, Upton, New York 11973 (United States)] [Collider-Accelerator Department, Brookhaven National Laboratory, Upton, New York 11973 (United States)

    2014-02-15

    Extracted ion beams from the test laser ion source (LIS) were transported through a test beam transport line which is almost identical to the actual primary beam transport in the current electron beam ion source apparatus. The tested species were C, Al, Si, Cr, Fe, Cu, Ag, Ta, and Au. The all measured beam currents fulfilled the requirements. However, in the case of light mass ions, the recorded emittance shapes have larger aberrations and the RMS values are higher than 0.06 ??mm?mrad, which is the design goal. Since we have margin to enhance the beam current, if we then allow some beam losses at the injection point, the number of the single charged ions within the acceptance can be supplied. For heaver ions like Ag, Ta, and Au, the LIS showed very good performance.

  8. Sandia National Laboratories: Ion Beam 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust, High-ThroughputUpcoming Release of thePrograms: Center forFacebookFactIon Beam Lab

  9. Method of automatic measurement and focus of an electron beam and apparatus therefore

    DOE Patents [OSTI]

    Giedt, W.H.; Campiotti, R.

    1996-01-09

    An electron beam focusing system, including a plural slit-type Faraday beam trap, for measuring the diameter of an electron beam and automatically focusing the beam for welding is disclosed. Beam size is determined from profiles of the current measured as the beam is swept over at least two narrow slits of the beam trap. An automated procedure changes the focus coil current until the focal point location is just below a workpiece surface. A parabolic equation is fitted to the calculated beam sizes from which optimal focus coil current and optimal beam diameter are determined. 12 figs.

  10. Method of automatic measurement and focus of an electron beam and apparatus therefor

    DOE Patents [OSTI]

    Giedt, Warren H. (San Jose, CA); Campiotti, Richard (Livermore, CA)

    1996-01-01

    An electron beam focusing system, including a plural slit-type Faraday beam trap, for measuring the diameter of an electron beam and automatically focusing the beam for welding. Beam size is determined from profiles of the current measured as the beam is swept over at least two narrow slits of the beam trap. An automated procedure changes the focus coil current until the focal point location is just below a workpiece surface. A parabolic equation is fitted to the calculated beam sizes from which optimal focus coil current and optimal beam diameter are determined.

  11. 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 ...

  12. Effects of Ion Beam on Nanoindentation Characteristics of Glassy...

    Office of Scientific and Technical Information (OSTI)

    74 ATOMIC AND MOLECULAR PHYSICS; BRAZIL; CARBON; CARBONIZATION; CHAINS; GOLD; HARDNESS; HEAT TREATMENTS; ION BEAMS; MODIFICATIONS; OXYGEN; RECOMBINATION; RESINS; SILICON; TAIL...

  13. Inhomogeneity smoothing using density valley formed by ion beam...

    Office of Scientific and Technical Information (OSTI)

    Inhomogeneity smoothing using density valley formed by ion beam deposition in ICF fuel pellet Citation Details In-Document Search Title: Inhomogeneity smoothing using density...

  14. Beam-line considerations for experiments with highly-charged ions

    SciTech Connect (OSTI)

    Johnson, B.M.

    1990-01-01

    The APS offers exciting possibilities for a bright future in x-ray research. For example, measurements on the inner-shell photoionization of ions will be feasible using stored ions in ions traps or ion beams from an electron-cyclotron-resonance ion source, or perhaps even a heavy-ion storage ring. Such experiments with ionic targets are the focus for the discussion given here on the optimization of photon flux on a generic beamline at the APS. The performance of beam lines X26C, X26A, and X17 on the x-ray ring of the National Synchrotron Light Source will be discussed as specific examples of beam-line design considerations.

  15. DEVELOPMENT OF EMITTANCE ANALYSIS SOFTWARE FOR ION BEAM CHARACTERIZATION

    SciTech Connect (OSTI)

    Padilla, M. J.; Liu, Y.

    2007-01-01

    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.

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

    SciTech Connect (OSTI)

    Miyamoto, N. Okajima, Y.; Wada, M.

    2014-02-15

    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.

  17. Observation of Beam ION Instability in Spear3

    SciTech Connect (OSTI)

    Teytelman, D.; /Dimtel, Redwood City; Cai, Y.; Corbett, W.J.; Raubenheimer, T.O.; Safranek, J.A.; Schmerge, J.F.; Sebek, J.J.; Wang, L.; /SLAC

    2011-12-14

    Weak vertical coupled bunch instability with oscillation amplitude at {mu}m level has been observed in SPEAR3. The instability becomes stronger when there is a vacuum pressure rise by partially turning off vacuum pumps and it becomes weaker when the vertical beam emittance is increased by turning off the skew quadrupole magnets. These confirmed that the instability was driven by ions in the vacuum. The threshold of the beam ion instability when running with a single bunch train is just under 200 mA. This paper presents the comprehensive observations of the beam ion instability in SPEAR3. The effects of vacuum pressure, beam current, beam filling pattern, chromaticity, beam emittance and bunch-by-bunch feedback are investigated in great detail. In an electron accelerator, ions generated from the residual gas molecules can be trapped by the beam. Then these trapped ions interact resonantly with the beam and cause beam instability and emittance blow-up. Most existing light sources use a long single bunch train filling pattern, followed by a long gap to avoid multi-turn ion trapping. However, such a gap does not preclude ions from accumulating during one passage of the single bunch train beam, and those ions can still cause a Fast Ion Instability (FII) as predicted by Raubenheimer and Zimmermann. FII has been observed in ALS, and PLS by artificially increasing the vacuum pressure by injecting helium gas into the vacuum chamber or by turning off the ion pumps in order to observe the beam ion instability. In some existing rings, for instance B factory, the beam ion instability was observed at the beginning of the machine operation after a long period of shutdown and then it automatically disappeared when the vacuum was better. However, when the beam emittance becomes smaller, the FII can occur at nominal conditions as observed in PLS, SOLEIL and SSRF. This paper reports the observations of beam ion instabilities in SPEAR3 under different condition during a period of one year, which includes single bunch train instability (FII) and multi-bunch train instability. Note that the instability may be not the same even with the same beam due to the change of the vacuum with time. SPEAR3 has a circumference of 234 m with a harmonic number of 372. SPEAR3 runs with six bunch train filling pattern in order to suppress the possible beam ion instability. Table 1 lists the main parameters of SPEAR3. The vacuum of SPEAR3 ranges from 0.1 to 0.5 nTorr, which varies from section to section.

  18. Optics of ion beams for the neutral beam injection system on HL-2A Tokamak

    SciTech Connect (OSTI)

    Zou, G. Q.; Lei, G. J.; Cao, J. Y.; Duan, X. R.

    2012-07-15

    The ion beam optics for the neutral beam injection system on HL-2A Tokomak is studied by two- dimensional numerical simulation program firstly, where the emitting surface is taken at 100 Debye lengths from the plasma electrode. The mathematical formulation, computation techniques are described. Typical ion orbits, equipotential contours, and emittance diagram are shown. For a fixed geometry electrode, the effect of plasma density, plasma potential and plasma electron temperature on ion beam optics is examined, and the calculation reliability is confirmed by experimental results. In order to improve ion beam optics, the application of a small pre-acceleration voltage ({approx}100 V) between the plasma electrode and the arc discharge anode is reasonable, and a lower plasma electron temperature is desired. The results allow optimization of the ion beam optics in the neutral beam injection system on HL-2A Tokomak and provide guidelines for designing future neutral beam injection system on HL-2M Tokomak.

  19. 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

  20. 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

    2010-02-03

    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.

  1. Direct plasma injection scheme with various ion beams

    SciTech Connect (OSTI)

    Okamura, M.

    2010-09-15

    The laser ion source is one of the most powerful heavy ion sources. However, it is difficult to obtain good stability and to control its intense current. To overcome these difficulties, we proposed a new beam injection scheme called 'direct plasma injection scheme'. Following this it was established to provide various species with desired charge state as an intense accelerated beam. Carbon, aluminum and iron beams have been tested.

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

    DOE Patents [OSTI]

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

    2008-02-26

    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.

  3. Terahertz generation by two cross focused laser beams in collisional plasmas

    SciTech Connect (OSTI)

    Sharma, R. P., E-mail: rpsharma@ces.iitd.ernet.in; Singh, Ram Kishor, E-mail: ram007kishor@gmail.com [Centre for Energy Studies, Indian Institute of Technology Delhi, New Delhi 110016 (India)

    2014-07-15

    The role of two cross-focused spatial-Gaussian laser beams has been studied for the high power and efficient terahertz (THz) radiation generation in the collisional plasma. The nonlinear current at THz frequency arises on account of temperature dependent collision frequency of electrons with ions in the plasma and the presence of a static electric field (applied externally in the plasma) and density ripple. Optimisation of laser-plasma parameters gives the radiated THz power of the order of 0.23??MW.

  4. Gas Transport and Density Control in the HYLIFE Heavy-Ion Beam Lines

    SciTech Connect (OSTI)

    Debonnel, Christophe S.; Welch, Dale R.; Rose, David V.; Lawrence, Simon S.Yu; Peterson, Per F

    2003-05-15

    The effective propagation and focusing of heavy-ion beams in the final-focus magnet region of inertial fusion target chambers require controlling the background gas density and pressure in the beam tubes. Liquid vortexes will coat the inside of the tubes next to the beam ports and will help eliminate the need for mechanical shutters to mitigate the venting of target chamber background gas into the final-focus magnet region. Before the neutralizing region, the beam space charge is high, and ablation and target debris deposition in the final-focus magnet region may cause voltage breakdown. Previous studies focused on evaluating the amount of target chamber debris reaching the entrance of the beam ports. The TSUNAMI code has now been used to assess the density, temperature, and velocity of the vortex debris transported {approx}3 m up the beam tubes and reaching the final-focus magnet region, assuming that the liquid vortexes are perfectly absorbing surfaces. To further mitigate debris deposition in the final-focus magnet region, and prevent voltage breakdown, a 'magnetic shutter' has been envisaged to divert the debris out of the final-focus region. This shutter will prevent the hot ablation debris from reaching the magnet region and, coupled to some ionizing scheme, will conveniently suppress early ingression of debris into the final-focus magnet region.

  5. Preliminary result of rapid solenoid for controlling heavy-ion beam parameters of laser ion source

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Okamura, M.; Sekine, M.; Ikeda, S.; Kanesue, T.; Kumaki, M.; Fuwa, Y.

    2015-03-13

    To realize a heavy ion inertial fusion driver, we have studied a possibility of laser ion source (LIS). A LIS can provide high current high brightness heavy ion beams, however it was difficult to manipulate the beam parameters. To overcome the issue, we employed a pulsed solenoid in the plasma drift section and investigated the effect of the solenoid field on singly charged iron beams. The rapid ramping magnetic field could enhance limited time slice of the current and simultaneously the beam emittance changed accordingly. This approach may also useful to realize an ion source for HIF power plant.

  6. Transverse Centroid Oscillations in Solenoidially Focused Beam Transport Lattices

    SciTech Connect (OSTI)

    Lund, S M; Wootton, C J; Lee, E P

    2008-08-01

    Linear equations of motion are derived that describe small-amplitude centroid oscillations induced by displacement and rotational misalignments of the focusing solenoids in the transport lattice, dipole steering elements, and initial centroid offset errors. These equations are analyzed in a local rotating Larmor frame to derive complex-variable 'alignment functions' and 'bending functions' that efficiently describe the characteristics of the centroid oscillations induced by mechanical misalignments of the solenoids and dipole steering elements. The alignment and bending functions depend only on properties of the ideal lattice in the absence of errors and steering and have associated expansion amplitudes set by the misalignments and steering fields. Applications of this formulation are presented for statistical analysis of centroid deviations, calculation of actual lattice misalignments from centroid measurements, and optimal beam steering.

  7. Transverse centroid oscillations in solenoidially focused beam transport lattices

    SciTech Connect (OSTI)

    Lund, Steven M.; Wootton, Christopher J.; Lee, Edward P.

    2008-08-01

    Linear equations of motion are derived that describe small-amplitude centroid oscillations induced by displacement and rotational misalignments of the focusing solenoids in the transport lattice, dipole steering elements, and initial centroid offset errors. These equations are analyzed in a local rotating Larmor frame to derive complex-variable"alignment functions" and"bending functions" that efficiently describe the characteristics of the centroid oscillations induced by mechanical misalignments of the solenoids and dipole steering elements. The alignment and bending functions depend only on properties of the ideal lattice in the absence of errors and steering and have associated expansion amplitudes set by the misalignments and steering fields. Applications of this formulation are presented for statistical analysis of centroid deviations, calculation of actual lattice misalignments from centroid measurements, and optimal beam steering.

  8. Ion beam collimating grid to reduce added defects

    DOE Patents [OSTI]

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

    2003-01-01

    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.

  9. Ion-beam and electron-beam irradiation of synthetic britholite S. Utsunomiya a

    E-Print Network [OSTI]

    Utsunomiya, Satoshi

    Ion-beam and electron-beam irradiation of synthetic britholite S. Utsunomiya a , S. Yudintsev b , L ). The sequence of increasing Tc correlates with the mass of the incident ion; whereas, the ratio of electronic to nuclear stopping power (ENSP) is inversely correlated with Tc. Electron irradiations were conducted

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

    SciTech Connect (OSTI)

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

    2010-01-04

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

  11. Method for reduction of selected ion intensities in confined ion beams

    DOE Patents [OSTI]

    Eiden, Gregory C. (Richland, WA); Barinaga, Charles J. (Richland, WA); Koppenaal, David W. (Richland, WA)

    1998-01-01

    A method for producing an ion beam having an increased proportion of analyte ions compared to carrier gas ions is disclosed. Specifically, the method has the step of addition of a charge transfer gas to the carrier analyte combination that accepts charge from the carrier gas ions yet minimally accepts charge from the analyte ions thereby selectively neutralizing the carrier gas ions. Also disclosed is the method as employed in various analytical instruments including an inductively coupled plasma mass spectrometer.

  12. Apparatus for reduction of selected ion intensities in confined ion beams

    DOE Patents [OSTI]

    Eiden, Gregory C. (Richland, WA); Barinaga, Charles J. (Richland, WA); Koppenaal, David W. (Richland, WA)

    2001-01-01

    An apparatus for producing an ion beam having an increased proportion of analyte ions compared to carrier gas ions is disclosed. Specifically, the apparatus has an ion trap or a collision cell containing a reagent gas wherein the reagent gas accepts charge from the analyte ions thereby selectively neutralizing the carrier gas ions. Also disclosed is the collision cell as employed in various locations within analytical instruments including an inductively coupled plasma mass spectrometer.

  13. Method for reduction of selected ion intensities in confined ion beams

    DOE Patents [OSTI]

    Eiden, G.C.; Barinaga, C.J.; Koppenaal, D.W.

    1998-06-16

    A method for producing an ion beam having an increased proportion of analyte ions compared to carrier gas ions is disclosed. Specifically, the method has the step of addition of a charge transfer gas to the carrier analyte combination that accepts charge from the carrier gas ions yet minimally accepts charge from the analyte ions thereby selectively neutralizing the carrier gas ions. Also disclosed is the method as employed in various analytical instruments including an inductively coupled plasma mass spectrometer. 7 figs.

  14. The direct injection of intense ion beams from a high field electron cyclotron resonance ion source into a radio frequency quadrupole

    SciTech Connect (OSTI)

    Rodrigues, G. Kanjilal, D.; Roy, A.; Becker, R.; Baskaran, R.

    2014-02-15

    The ion current achievable from high intensity ECR sources for highly charged ions is limited by the high space charge. This makes classical extraction systems for the transport and subsequent matching to a radio frequency quadrupole (RFQ) accelerator less efficient. The direct plasma injection (DPI) method developed originally for the laser ion source avoids these problems and uses the combined focusing of the gap between the ion source and the RFQ vanes (or rods) and the focusing of the rf fields from the RFQ penetrating into this gap. For high performance ECR sources that use superconducting solenoids, the stray magnetic field of the source in addition to the DPI scheme provides focusing against the space charge blow-up of the beam. A combined extraction/matching system has been designed for a high performance ECR ion source injecting into an RFQ, allowing a total beam current of 10 mA from the ion source for the production of highly charged {sup 238}U{sup 40+} (1.33 mA) to be injected at an ion source voltage of 60 kV. In this design, the features of IGUN have been used to take into account the rf-focusing of an RFQ channel (without modulation), the electrostatic field between ion source extraction and the RFQ vanes, the magnetic stray field of the ECR superconducting solenoid, and the defocusing space charge of an ion beam. The stray magnetic field is shown to be critical in the case of a matched beam.

  15. Etching of Graphene Devices with a Helium Ion Beam

    E-Print Network [OSTI]

    Baugher, Britton W. H.

    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 ...

  16. Transverse coupling property of beam from ECR ion sources

    SciTech Connect (OSTI)

    Yang, Y.; Yuan, Y. J.; Sun, L. T.; Feng, Y. C.; Fang, X.; Cao, Y.; Lu, W.; Zhang, X. Z.; Zhao, H. W.

    2014-11-15

    Experimental evidence of the property of transverse coupling of beam from Electron Cyclotron Resonance (ECR) ion source is presented. It is especially of interest for an ECR ion source, where the cross section of extracted beam is not round along transport path due to the magnetic confinement configuration. When the ions are extracted and accelerated through the descending axial magnetic field at the extraction region, the horizontal and vertical phase space strongly coupled. In this study, the coupling configuration between the transverse phase spaces of the beam from ECR ion source is achieved by beam back-tracking simulation based on the measurements. The reasonability of this coupling configuration has been proven by a series of subsequent simulations.

  17. 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)

    2014-02-15

    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.

  18. Rapid Coarsening of Ion Beam Ripple Patterns by Defect Annihilation

    SciTech Connect (OSTI)

    Hansen, Henri; Messlinger, Sebastian; Stoian, Georgiana [I. Physikalisches Institut, RWTH Aachen, 52056 Aachen (Germany); Redinger, Alex [I. Physikalisches Institut, RWTH Aachen, 52056 Aachen (Germany); II. Physikalisches Institut, Universitaet zu Koeln, 50937 Koeln, Zuelpicher Strasse 77 (Germany); Krug, Joachim [Institut fuer Theoretische Physik, Universitaet zu Koeln, 50937 Koeln, Zuelpicher Strasse 77 (Germany); Michely, Thomas [II. Physikalisches Institut, Universitaet zu Koeln, 50937 Koeln, Zuelpicher Strasse 77 (Germany)

    2009-04-10

    Ripple patterns formed on Pt(111) through grazing incidence ion beam erosion coarsen rapidly. At and below 450 K coarsening of the patterns is athermal and kinetic, unrelated to diffusion and surface free energy. Similar to the situation for sand dunes, coarsening takes place through annihilation reactions of mobile defects in the pattern. The defect velocity derived on the basis of a simple model agrees quantitatively with the velocity of monatomic steps illuminated by the ion beam.

  19. Overview of Light-Ion Beam Therapy

    SciTech Connect (OSTI)

    Chu, William T.

    2006-03-16

    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

  20. 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)

    2014-08-15

    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.

  1. An ion guide laser ion source for isobar-suppressed rare isotope beams

    SciTech Connect (OSTI)

    Raeder, Sebastian Ames, Friedhelm; Bishop, Daryl; Bricault, Pierre; Kunz, Peter; Mjøs, Anders; Heggen, Henning; Institute of Applied Physics, TU Darmstadt, Schlossgartenstr. 7, 64289 Darmstadt ; Lassen, Jens Teigelhöfer, Andrea; Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2

    2014-03-15

    Modern experiments at isotope separator on-line (ISOL) facilities like ISAC at TRIUMF often depend critically on the purity of the delivered rare isotope beams. Therefore, highly selective ion sources are essential. This article presents the development and successful on-line operation of an ion guide laser ion source (IG-LIS) for the production of ion beams free of isobaric contamination. Thermionic ions from the hot ISOL target are suppressed by an electrostatic potential barrier, while neutral radio nuclides effusing out are resonantly ionized by laser radiation within a quadrupole ion guide behind this barrier. The IG-LIS was developed through detailed thermal and ion optics simulation studies and off-line tests with stable isotopes. In a first on-line run with a SiC target a suppression of surface-ionized Na contaminants in the ion beam of up to six orders of magnitude was demonstrated.

  2. A double-plasma source of continuous bipolar ion-ion beam

    SciTech Connect (OSTI)

    Dudin, S. V.; Scientific Center of Physical Technologies, Svobody sq. 6, 61022 Kharkiv ; Rafalskyi, D. V.

    2013-01-21

    A double-plasma source capable of the generation of a continuous bipolar ion-ion beam is described. The quasi-neutral ion-ion flow to an extraction electrode is formed in the system containing primary inductively coupled plasma separated from a secondary plasma by an electrostatic grid-type filter. The total current of each ion species to the 250 mm diameter extraction electrode is about 80 mA; the electron current does not exceed 30% of the ion current. Method of positive/negative ion current ratio control is proposed, allowing the ion currents ratio variation in wide range.

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

    SciTech Connect (OSTI)

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

    2012-05-20

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

  4. Simulations and experiments of intense ion beam compression in space and time.

    SciTech Connect (OSTI)

    Yu, S. S. (Lawrence Berkeley National Laboratory, Berkeley, CA); Seidl, P. A. (Lawrence Berkeley National Laboratory, Berkeley, CA); Roy, P. K. (Lawrence Berkeley National Laboratory, Berkeley, CA); Lidia, S. M. (Lawrence Berkeley National Laboratory, Berkeley, CA); Coleman, J. E. (Lawrence Berkeley National Laboratory, Berkeley, CA); Kaganovich, I. D. (Princeton Plasma Physics Laboratory, Princeton, NJ); Gilson, E. P. (Princeton Plasma Physics Laboratory, Princeton, NJ); Welch, Dale Robert; Sefkow, Adam B.; Davidson, R. C. (Princeton Plasma Physics Laboratory, Princeton, NJ)

    2008-12-01

    The Heavy Ion Fusion Science Virtual National Laboratory has achieved 60-fold longitudinal pulse compression of ion beams on the Neutralized Drift Compression Experiment (NDCX) [P. K. Roy et al., Phys. Rev. Lett. 95, 234801 (2005)]. To focus a space-charge-dominated charge bunch to sufficiently high intensities for ion-beam-heated warm dense matter and inertial fusion energy studies, simultaneous transverse and longitudinal compression to a coincident focal plane is required. Optimizing the compression under the appropriate constraints can deliver higher intensity per unit length of accelerator to the target, thereby facilitating the creation of more compact and cost-effective ion beam drivers. The experiments utilized a drift region filled with high-density plasma in order to neutralize the space charge and current of an {approx}300 keV K{sup +} beam and have separately achieved transverse and longitudinal focusing to a radius <2 mm and pulse duration <5 ns, respectively. Simulation predictions and recent experiments demonstrate that a strong solenoid (B{sub Z} < 100 kG) placed near the end of the drift region can transversely focus the beam to the longitudinal focal plane. This paper reports on simulation predictions and experimental progress toward realizing simultaneous transverse and longitudinal charge bunch focusing. The proposed NDCX-II facility would capitalize on the insights gained from NDCX simulations and measurements in order to provide a higher-energy (>2 MeV) ion beam user-facility for warm dense matter and inertial fusion energy-relevant target physics experiments.

  5. HIGHLY COMPRESSED ION BEAMS FOR HIGH ENERGY DENSITY SCIENCE

    E-Print Network [OSTI]

    Wurtele, Jonathan

    HIGHLY COMPRESSED ION BEAMS FOR HIGH ENERGY DENSITY SCIENCE A. Friedman1,2 , J.J.Barnard1,2 , R Energy Density regimes required for Inertial Fu- sion Energy and other applications. An interim goal we are pursuing, low to medium mass ions with energies just above the Bragg peak are directed onto

  6. Shunting arc plasma source for pure carbon ion beam

    SciTech Connect (OSTI)

    Koguchi, H.; Sakakita, H.; Kiyama, S.; Shimada, T.; Sato, Y.; Hirano, Y.

    2012-02-15

    A plasma source is developed using a coaxial shunting arc plasma gun to extract a pure carbon ion beam. The pure carbon ion beam is a new type of deposition system for diamond and other carbon materials. Our plasma device generates pure carbon plasma from solid-state carbon material without using a hydrocarbon gas such as methane gas, and the plasma does not contain any hydrogen. The ion saturation current of the discharge measured by a double probe is about 0.2 mA/mm{sup 2} at the peak of the pulse.

  7. 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)

    2014-02-15

    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.

  8. Electron Gun For Multiple Beam Klystron Using Magnetic Focusing

    DOE Patents [OSTI]

    Ives, R. Lawrence (Saratoga, CA); Miram, George (Atherton, CA); Krasnykh, Anatoly (Santa Clara, CA)

    2004-07-27

    An RF device comprising a plurality of drift tubes, each drift tube having a plurality of gaps defining resonant cavities, is immersed in an axial magnetic field. RF energy is introduced at an input RF port at one of these resonant cavities and collected at an output RF port at a different RF cavity. A plurality of electron beams passes through these drift tubes, and each electron beam has an individual magnetic shaping applied which enables confined beam transport through the drift tubes.

  9. Design and Fabrication of the Lithium Beam Ion Injector for NDCX-II

    E-Print Network [OSTI]

    Takakuwa, J.

    2011-01-01

    research utilizing a lithium ion (Li+) beam with a currentthe alumina- silicate lithium ion source being, among otherand Fabrication of the Lithium Beam Ion Injector for NDCX-II

  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)

    2014-02-15

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

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

    SciTech Connect (OSTI)

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

    2002-12-01

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

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

    SciTech Connect (OSTI)

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

    2010-03-16

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

  13. 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.

    2008-08-01

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

  14. Numerical simulation of ion charge breeding in electron beam ion source

    SciTech Connect (OSTI)

    Zhao, L., E-mail: zhao@far-tech.com; Kim, Jin-Soo [FAR-TECH, Inc., San Diego, California 92122 (United States)] [FAR-TECH, Inc., San Diego, California 92122 (United States)

    2014-02-15

    The Electron Beam Ion Source particle-in-cell code (EBIS-PIC) tracks ions in an EBIS electron beam while updating electric potential self-consistently and atomic processes by the Monte Carlo method. Recent improvements to the code are reported in this paper. The ionization module has been improved by using experimental ionization energies and shell effects. The acceptance of injected ions and the emittance of extracted ion beam are calculated by extending EBIS-PIC to the beam line transport region. An EBIS-PIC simulation is performed for a Cs charge-breeding experiment at BNL. The charge state distribution agrees well with experiments, and additional simulation results of radial profiles and velocity space distributions of the trapped ions are presented.

  15. 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)

    2012-02-15

    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.

  16. Individual addressing of trapped $^{171}$Yb$^+$ ion qubits using a MEMS-based beam steering system

    E-Print Network [OSTI]

    S. Crain; E. Mount; S. Baek; J. Kim

    2014-09-18

    The ability to individually manipulate the increasing number of qubits is one of the many challenges towards scalable quantum information processing with trapped ions. Using micro-mirrors fabricated with micro-electromechanical systems (MEMS) technology, we focus laser beams on individual ions in a linear chain and steer the focal point in two dimensions. We demonstrate sequential single qubit gates on multiple $^{171}$Yb$^+$ qubits and characterize the gate performance using quantum state tomography. Our system features negligible crosstalk to neighboring ions ($< 3\\times 10^{-4}$), and switching speed comparable to typical single qubit gate times ($<$ 2 $\\mu$s).

  17. Individual addressing of trapped $^{171}$Yb$^+$ ion qubits using a MEMS-based beam steering system

    E-Print Network [OSTI]

    Crain, S; Baek, S; Kim, J

    2014-01-01

    The ability to individually manipulate the increasing number of qubits is one of the many challenges towards scalable quantum information processing with trapped ions. Using micro-mirrors fabricated with micro-electromechanical systems (MEMS) technology, we focus laser beams on individual ions in a linear chain and steer the focal point in two dimensions. We demonstrate sequential single qubit gates on multiple $^{171}$Yb$^+$ qubits and characterize the gate performance using quantum state tomography. Our system features negligible crosstalk to neighboring ions ($< 3\\times 10^{-4}$), and switching speed comparable to typical single qubit gate times ($<$ 2 $\\mu$s).

  18. Fusion Induced by Radioactive Ion Beams

    E-Print Network [OSTI]

    J. F. Liang; C. Signorini

    2005-04-26

    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.

  19. 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.

    2010-04-28

    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.

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

    DOE Patents [OSTI]

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

    1993-03-30

    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.

  1. 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)

    1993-01-01

    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.

  2. Polarized Ion Beams in Figure-8 Rings of JLab's MEIC

    SciTech Connect (OSTI)

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

    2014-07-01

    The Medium-energy Electron-Ion Collider (MEIC) proposed by Jefferson Lab is designed to provide high polarization of both colliding beams. One of the unique features of JLab's MEIC is figure-8 shape of its rings. It allows preservation and control of polarization of all ion species including small-anomalous-magnetic-moment deuterons during their acceleration and storage. The figure-8 design conceptually expands the capability of obtaining polarized high-energy beams in comparison to conventional designs because of its property of having no preferred periodic spin direction. This allows one to control effectively the beam polarization by means of magnetic insertions with small field integrals. We present a complete scheme for preserving the ion polarization during all stages of acceleration and its control in the collider's experimental straights.

  3. A self-sputtering ion source: A new approach to quiescent metal ion beams

    E-Print Network [OSTI]

    Oks, Efim M.

    2010-01-01

    ion beams from vacuum arc plasmas and HIPIMS self-sputteringion source because the vacuum arc plasma is produced at non-without the need for an arc trigger plasma, although it is

  4. 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)

    2011-03-08

    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.

  5. Cathode spot energy transfer simulated by a focused laser beam

    SciTech Connect (OSTI)

    Vogel, N.; Hoft, H. )

    1989-10-01

    Minimum conditions for the formation of surface craters by laser irradiation have been studied experimentally and theoretically for various metals. The critical power density for crater formation within 20 ns was about 10{sup 11}W/m{sup 2}. It is therefore concluded that crater formation by ion bombardment will require an ion current density of the order of 10{sup 10}A/m{sup 2}.

  6. PLASMA FOCUSING OF HIGH ENERGY DENSITY ELECTRON AND POSITRON BEAMS \\Lambda

    E-Print Network [OSTI]

    PLASMA FOCUSING OF HIGH ENERGY DENSITY ELECTRON AND POSITRON BEAMS \\Lambda J.S.T. Ng, P. Chen, W present results from the SLAC E­150 experiment on plasma focusing of high energy density electron and experiments to test this con­ cept were carried out with low energy density electron beams [2]. The goals

  7. Reducing ion beam noise of vacuum arc ion sources

    E-Print Network [OSTI]

    Anders, Andre; Hollinger, Ralph

    2001-01-01

    in the expanding vacuum arc plasma and operating in the ion3 Schematic of the vacuum arc plasma generator (arc cathodeUnfortunately, vacuum arc plasmas are rapidly fluctuating

  8. 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

    2012-12-01

    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.

  9. Review of ion beam therapy: Present and Future

    SciTech Connect (OSTI)

    Alonso, Jose R.

    2000-06-01

    First therapy efforts at the Bevalac using neon ions took place in the 70's and 80's. Promising results led to construction of HIMAC in Chiba Japan, and more recently to therapy trials at GSI. Both these facilities are now treating patients with carbon beams. Advances in both accelerator technology and beam delivery have taken place at these two centers. Plans are well along for new facilities in Europe and Japan.

  10. 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)

    2014-09-15

    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.

  11. The heavy ion beam diagnostic for the tokamak ISTTOK

    SciTech Connect (OSTI)

    Cabral, J.A.C.; Malaquias, A.; Praxedes, A.; Toledo, W. van; Varandas, C.A.F. )

    1994-08-01

    In this paper the authors describe the heavy ion beam diagnostic for the tokamak ISTTOK, which has been designed to determine the temporal evolution of the plasma density, poloidal magnetic field and plasma potential profiles. This diagnostic makes use of a new type of high density caesium plasma source, a multiple cell detector and a fast data acquisition system. The authors describe the numerical code for trajectory and beam attenuation simulations, a method for the experimental determination of the poloidal field profile, the ion gun and the detection, control and data acquisition systems. Calibration tests and the first experimental results are presented.

  12. Microwave Ion Source and Beam Injection for an Accelerator-drivenNeutron Source

    SciTech Connect (OSTI)

    Vainionpaa, J.H.; Gough, R.; Hoff, M.; Kwan, J.W.; Ludewigt,B.A.; Regis, M.J.; Wallig, J.G.; Wells, R.

    2007-02-15

    An over-dense microwave driven ion source capable ofproducing deuterium (or hydrogen) beams at 100-200 mA/cm2 and with atomicfraction>90 percent was designed and tested with an electrostaticlow energy beam transport section (LEBT). This ion source wasincorporatedinto the design of an Accelerator Driven Neutron Source(ADNS). The other key components in the ADNS include a 6 MeV RFQaccelerator, a beam bending and scanning system, and a deuterium gastarget. In this design a 40 mA D+ beam is produced from a 6 mm diameteraperture using a 60 kV extraction voltage. The LEBT section consists of 5electrodes arranged to form 2 Einzel lenses that focus the beam into theRFQ entrance. To create the ECR condition, 2 induction coils are used tocreate ~; 875 Gauss on axis inside the source chamber. To prevent HVbreakdown in the LEBT a magnetic field clamp is necessary to minimize thefield in this region. Matching of the microwave power from the waveguideto the plasma is done by an autotuner. We observed significantimprovement of the beam quality after installing a boron nitride linerinside the ion source. The measured emittance data are compared withPBGUNS simulations.

  13. Stationary self-focusing of intense laser beam in cold quantum plasma using ramp density profile

    SciTech Connect (OSTI)

    Habibi, M.; Ghamari, F.

    2012-10-15

    By using a transient density profile, we have demonstrated stationary self-focusing of an electromagnetic Gaussian beam in cold quantum plasma. The paper is devoted to the prospects of using upward increasing ramp density profile of an inhomogeneous nonlinear medium with quantum effects in self-focusing mechanism of high intense laser beam. We have found that the upward ramp density profile in addition to quantum effects causes much higher oscillation and better focusing of laser beam in cold quantum plasma in comparison to that in the classical relativistic case. Our computational results reveal the importance and influence of formation of electron density profiles in enhancing laser self-focusing.

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

    SciTech Connect (OSTI)

    Knapp, D.

    1994-11-02

    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.

  15. Microwave Ion Source and Beam Injection for an Accelerator-driven Neutron Source

    E-Print Network [OSTI]

    2007-01-01

    LBNL-62514 MICROWAVE ION SOURCE AND BEAM INJECTION FOR ANAbstract An over-dense microwave driven ion source capableregion. Matching of the microwave power from the waveguide

  16. Emittance growth of an nonequilibrium intense electron beam in a transport channel with discrete focusing

    SciTech Connect (OSTI)

    Carlsten, B.E.

    1997-02-01

    The author analyzes the emittance growth mechanisms for a continuous, intense electron beam in a focusing transport channel, over distances short enough that the beam does not reach equilibrium. The emittance grows from the effect of nonlinear forces arising from (1) current density nonuniformities, (2) energy variations leading to nonlinearities in the space-charge force even if the current density is uniform, (3) axial variations in the radial vector potential, (4) an axial velocity shear along the beam, and (5) an energy redistribution of the beam as the beam compresses or expands. The emittance growth is studied analytically and numerically for the cases of balanced flow, tight focusing, and slight beam scalloping, and is additionally studied numerically for an existing 6-MeV induction linear accelerator. Rules for minimizing the emittance along a beamline are established. Some emittance growth will always occur, both from current density nonuniformities that arise along the transport and from beam radius changes along the transport.

  17. Electrostatic energy analyzer measurements of low energy zirconium beam parameters in a plasma sputter-type negative ion source

    SciTech Connect (OSTI)

    Malapit, Giovanni M.; Mahinay, Christian Lorenz S.; Poral, Matthew D.; Ramos, Henry J.

    2012-02-15

    A plasma sputter-type negative ion source is utilized to produce and detect negative Zr ions with energies between 150 and 450 eV via a retarding potential-type electrostatic energy analyzer. Traditional and modified semi-cylindrical Faraday cups (FC) inside the analyzer are employed to sample negative Zr ions and measure corresponding ion currents. The traditional FC registered indistinct ion current readings which are attributed to backscattering of ions and secondary electron emissions. The modified Faraday cup with biased repeller guard ring, cut out these signal distortions leaving only ringings as issues which are theoretically compensated by fitting a sigmoidal function into the data. The mean energy and energy spread are calculated using the ion current versus retarding potential data while the beam width values are determined from the data of the transverse measurement of ion current. The most energetic negative Zr ions yield tighter energy spread at 4.11 eV compared to the least energetic negative Zr ions at 4.79 eV. The smallest calculated beam width is 1.04 cm for the negative Zr ions with the highest mean energy indicating a more focused beam in contrast to the less energetic negative Zr ions due to space charge forces.

  18. 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)

    2007-08-10

    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.

  19. 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

  20. 21st International Conference on Ion Beam Analysis

    SciTech Connect (OSTI)

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

    2014-08-01

    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.

  1. Study of 50 GeV proton beam focusing by novel crystal device

    E-Print Network [OSTI]

    Afonin, A G; Baranov, V T; Britvich, G I; Bugorskiy, A P; Bulgakov, M K; Chesnokov, Yu A; Chirkov, P N; Durum, A A; Lobanov, I S; Lunkov, A N; Lutchev, A V; Maisheev, V A; Sandomirskiy, Yu E; Skleznev, A V; Yanovich, A A; Yazynin, I A

    2012-01-01

    The bent crystals are applied on large accelerators to deflect particle beams in process of extraction and collimation. Recently the proposals of fixed target researches in the LHC are formulated. For realization of this program not only deflection but also focusing the LHC beam by bent crystals can be used. In the given work experimental results on 50 GeV proton beam focusing with the help of novel crystal device are reported. The positive property of this device is opportunity to work near the circulating beam of an accelerator, including the LHC.

  2. Focused Ion Beam Fabricated Non-equilibrium Superconducting Devices

    E-Print Network [OSTI]

    Moseley, Richard William

    . This work concentrates on the use of an FIB instrument for making superconducting devices. It is shown for the first time that planar-bridge (Nb/Cu/Nb) Superconductor/Normalmetal/ Superconductor (SNS) junctions can be reliably fabricated using a standard...

  3. Customized atomic force microscopy probe by focused-ion-beam...

    Office of Scientific and Technical Information (OSTI)

    that tall (18 m) cantilever tips fabricated by this approach reduce squeeze-film damping, which fits predictions from hydrodynamic theory, and results in an increased...

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

    SciTech Connect (OSTI)

    Lee, Y.H.Y.

    1998-05-01

    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.

  5. ACCELERATION SYSTEMS FOR HEAVY-ION BEAMS FOR INERTIAL CONFINEMENT FUSION

    E-Print Network [OSTI]

    Faltens, A.

    2010-01-01

    ION BEAMS FOR INERTIAL CONFINEMENT FUSION A. Fa1tens, D. L.ION BEAMS FOR INERTIAL CONFINEMENT FUSION A. Faltens, D.L.generation through inertial confinement fusion have been set

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

    SciTech Connect (OSTI)

    Whealton, J.H.; Raridon, R.J.; Leung, K.N.

    1997-12-01

    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.

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

    E-Print Network [OSTI]

    Iosilevskiy, Igor

    2010-01-01

    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.

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

    E-Print Network [OSTI]

    Igor Iosilevskiy; Victor Gryaznov

    2010-05-23

    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.

  9. Angular distribution of energetic argon ions emitted by a 90?kJ Filippov-type plasma focus

    SciTech Connect (OSTI)

    Pestehe, S. J.; Mohammadnejad, M.

    2015-02-15

    Characteristics of the energetic argon ions emitted by a 90?kJ Filippov-type plasma focus are studied by employing an array of Faraday cups. The Faraday cups are designed to minimize the secondary electron emission effects on their response. Angular distribution of the ions is measured, and the results indicate a highly anisotropic emission with a dip at the device axis and a local maximum at the angle of 7° with respect to the axis. It has been argued that this kind of anisotropic emission may be related to the surfatron acceleration mechanism and shown that this behavior is independent of the working gas pressure. It has been also demonstrated that this mechanism is responsible for the generation of MeV ions. Measuring the total ion number at different working gas pressures gives an optimum pressure of 0.3?Torr. In addition, the energy spectrum of ions is measured by taking into account of the ambient gas effects on the energy and charge of the ions. The current neutralization effect of electrons trapped in the ion beam as well as the effect of conducting boundaries surrounding the beam, on the detected signals are investigated.

  10. Three-dimensional light distribution near the focus of a tightly focused beam of few-cycle optical pulses

    SciTech Connect (OSTI)

    Romallosa, Kristine Marie; Bantang, Johnrob; Saloma, Caesar

    2003-09-01

    Via the Richards-Wolf vector diffraction theory, we analyze the three-dimensional intensity distribution of the focal volume that is produced by a strongly focused 750-nm beam of ultrafast, Gaussian-shaped optical pulses (10{sup -9} s{>=} pulse width {tau}{>=}1 fs=10{sup -15} s). Knowledge of the three-dimensional distribution near focus is essential in determining the diffraction-limited resolution of an optical microscope. The optical spectrum of a short pulse is characterized by side frequencies about the carrier frequency. The effect of spectral broadening on the focused intensity distribution is evaluated via the Linfoot's criteria of fidelity, structural content, and correlation quality and with reference to a 750-nm cw focused beam. Different values are considered for {tau} and numerical aperture of the focusing lens (0.1{<=}X{sub NA}{<=}1.2). At X{sub NA}=0.8, rapid deterioration of the focused intensity distribution is observed at {tau}=1.2 fs. This happens because a 750-nm optical pulse with {tau}=1.2 fs has an associated coherence length of 359.7 nm which is less than the Nyquist sampling interval of 375 nm that is required to sample 750 nm sinusoid without loss of information. The ill-effects of spectral broadening is weaker in two-photon excitation microscope than in its single-photon counterpart for the same focusing lens and light source.

  11. 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

    2010-12-28

    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.

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

    DOE Patents [OSTI]

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

    2003-04-29

    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.

  13. Applied Physics B28, 2/3 239 cw Ion Lasers Pumpedby Electron Beams

    E-Print Network [OSTI]

    Rocca, Jorge J.

    Applied Physics B28, 2/3 239 cw Ion Lasers Pumpedby Electron Beams J. J. Rocca, J. D. Meyer, Zeng, and As by exciting He metal-vapor mixtures with a dc electron beam. The beam is generated by glow discharge electron obtained using electron beam excitation. The conventional manner of exciting cw ion lasers is to use

  14. Means for the focusing and acceleration of parallel beams of charged particles. [Patent application

    DOE Patents [OSTI]

    Maschke, A.W.

    1980-09-23

    Apparatus for focusing beams of charged particles comprising planar arrays of electrostatic quadrupoles. The array may be assembled from a single component which comprises a support plate containing uniform rows of poles. Each pole is separated by a hole through the plate designed to pass a beam. Two such plates may be positioned with their poles intermeshed to form a plurality of quadrupoles.

  15. Means for the focusing and acceleration of parallel beams of charged particles

    DOE Patents [OSTI]

    Maschke, Alfred W. (East Moriches, NY)

    1982-09-21

    Apparatus for focusing beams of charged particles comprising planar arrays of electrostatic quadrupoles. The array may be assembled from a single component which comprises a support plate containing uniform rows of poles. Each pole is separated by a hole through the plate designed to pass a beam. Two such plates may be positioned with their poles intermeshed to form a plurality of quadrupoles.

  16. Optimized electrode placement along the channel of a Hall thruster for ion focusing

    SciTech Connect (OSTI)

    Qing, Shaowei, E-mail: qshaowei@gmail.com [Power Engineering Institute, Chongqing University, Chongqing 400044 (China); E, Peng [Department of Electrical Engineering, Harbin Institute of Technology, Harbin 150001 (China); Xia, Guangqing [State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian University of Technology, Dalian 116024 (China); Tang, Ming-Chun [College of Communication Engineering, Chongqing University, Chongqing 400044 (China); Duan, Ping [School of Physics, Dalian Maritime University, Dalian 116026 (China)

    2014-01-21

    An optimal placement of the segmented electrode for increasing the lifetime of the Aton-type Hall thruster, i.e., reducing the plume divergence, is demonstrated using a 2D3V fully kinetic Particle-in-Cell method. Segmented electrodes, embedded near the ionization region of non-segmented case and biased above anode potential, lead to an increased separation between the ionization and acceleration regions and the formation of an efficient acceleration electric field configuration as potential lens. Due to this electrode placement, the sheath near the ceramic walls of the acceleration region is collapsed and an excellent ion beam focusing is demonstrated. The potential contour pockets around the electrodes and the sheath collapse phenomenon are also discussed.

  17. Temporal Development of Ion Beam Mean Charge State in PulsedVacuum Arc Ion Sources

    SciTech Connect (OSTI)

    Oks, Efim M.; Yushkov, Georgy Yu.; Anders, Andre

    2007-06-21

    Vacuum arc ion sources, commonly also known as "Mevva" ionsources, are used to generate intense pulsed metal ion beams. It is knownthat the mean charge state of the ion beam lies between 1 and 4,depending on cathode material, arc current, arc pulse duration, presenceor absence of magnetic field at the cathode, as well background gaspressure. A characteristic of the vacuum arc ion beam is a significantdecrease in ion charge state throughout the pulse. This decrease can beobserved up to a few milliseconds, until a "noisy" steady-state value isestablished. Since the extraction voltage is constant, a decrease in theion charge state has a proportional impact on the average ion beamenergy. This paper presents results of detailed investigations of theinfluence of arc parameters on the temporal development of the ion beammean charge state for a wide range of cathode materials. It is shown thatfor fixed pulse duration, the charge state decrease can be reduced bylower arc current, higher pulse repetition rate, and reduction of thedistance between cathode and extraction region. The latter effect may beassociated with charge exchange processes in the dischargeplasma.

  18. First test of BNL electron beam ion source with high current density electron beam

    SciTech Connect (OSTI)

    Pikin, Alexander Alessi, James G. Beebe, Edward N.; Shornikov, Andrey; Mertzig, Robert; Wenander, Fredrik; Scrivens, Richard

    2015-01-09

    A new electron gun with electrostatic compression has been installed at the Electron Beam Ion Source (EBIS) Test Stand at BNL. This is a collaborative effort by BNL and CERN teams with a common goal to study an EBIS with electron beam current up to 10 A, current density up to 10,000 A/cm{sup 2} and energy more than 50 keV. Intensive and pure beams of heavy highly charged ions with mass-to-charge ratio < 4.5 are requested by many heavy ion research facilities including NASA Space Radiation Laboratory (NSRL) at BNL and HIE-ISOLDE at CERN. With a multiampere electron gun, the EBIS should be capable of delivering highly charged ions for both RHIC facility applications at BNL and for ISOLDE experiments at CERN. Details of the electron gun simulations and design, and the Test EBIS electrostatic and magnetostatic structures with the new electron gun are presented. The experimental results of the electron beam transmission are given.

  19. Photon trap for neutralization of negative ions beams

    E-Print Network [OSTI]

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

    2015-01-01

    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.

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

    SciTech Connect (OSTI)

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

    2014-09-09

    To minimize operational complexities, setup of collisions in high energy circular colliders typically involves acceleration with near constant ?-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. Theoretical and Computational Investigation of Periodically Focused Intense Charged-Particle Beams

    SciTech Connect (OSTI)

    Chen, Chiping [Massachusetts Institute of Technology

    2013-06-26

    The purpose of this report is to summarize results of theoretical and computational investigations of periodically focused intense charged-particle beams in parameter regimes relevant to the development of advanced high-brightness, high-power accelerators for high-energy physics research. The breakthroughs and highlights in our research in the period from April 1, 2010 to March 30, 2013 were: a) Theory and simulation of adiabatic thermal Child-Langmuir flow; b) Particle-in-cell simulations of adiabatic thermal beams in periodic solenoidal focusing field; c)Dynamics of charged particles in an adiabatic thermal beam equilibrium in a periodic solenoidal focusing field; d) Training of undergraduate researchers and graduate student in accelerator and beam physics. A brief introduction and summary is presented. Detailed descriptions of research results are provided in an appendix of publications at the end of the report.

  2. Exact analytical expression for the electromagnetic field in a focused laser beam or pulse

    E-Print Network [OSTI]

    Alexander M. Fedotov; Konstantin Yu. Korolev; Maxim V. Legkov

    2007-05-18

    We present a new class of exact nonsingular solutions for the Maxwell equations in vacuum, which describe the electromagnetic field of the counterpropagating focused laser beams and the subperiod focused laser pulse. These solutions are derived by the use of a modification of the "complex source method", investigated and visualized.

  3. First Beam Waist Measurements in the Final Focus Beam Line at...

    Office of Scientific and Technical Information (OSTI)

    a purpose to reach a 37 nm vertical beam size at the interaction point using compact optics based on a novel scheme of local chromaticity correction. Construction of all...

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

    SciTech Connect (OSTI)

    Mark Spitzer

    2011-03-11

    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.

  5. Response of SOI image sensor to therapeutic carbon ion beam

    E-Print Network [OSTI]

    Matsumura, Akihiko

    2015-01-01

    Carbon ion radiotherapy is known as a less invasive cancer treatment. The radiation quality is an important parameter to evaluate the biological effect and the clinical dose from the measured physical dose. The performance of SOPHIAS detector, which is the SOI image sensor having a wide dynamic range and large active area, was tested by using therapeutic carbon ion beam at Gunma University Heavy Ion Medical Center (GHMC). It was shown that the primary carbon and secondary particles can be distinguishable by SOPHIAS detector. On the other hand, a LET dependence was observed especially at the high LET region. This phenomenon will be studied by using the device simulator together with Monte Carlo simulation.

  6. The Development and Utilization of the Periodic Focusing Ion Funnel 

    E-Print Network [OSTI]

    Fort, Kyle Logan

    2014-12-09

    Ion mobility-mass spectrometry (IM-MS) provides gas phase, size-based separation, on an ultrafast timescale (?s-ms). With the incorporation of electrospray ionization, IM-MS is a valuable tool to investigate conformations ...

  7. 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)

    2008-03-04

    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.

  8. The energy transfer in the TEMP-4M pulsed ion beam accelerator

    SciTech Connect (OSTI)

    Isakova, Y. I.; Pushkarev, A. I.; Khaylov, I. P.

    2013-07-15

    The results of a study of the energy transfer in the TEMP-4M pulsed ion beam accelerator are presented. The energy transfer efficiency in the Blumlein and a self-magnetically insulated ion diode was analyzed. Optimization of the design of the accelerator allows for 85% of energy transferred from Blumlein to the diode (including after-pulses), which indicates that the energy loss in Blumlein and spark gaps is insignificant and not exceeds 10%–12%. Most losses occur in the diode. The efficiency of energy supplied to the diode to the energy of accelerated ions is 8%–9% for a planar strip self-magnetic MID, 12%–15% for focusing diode and 20% for a spiral self-magnetic MID.

  9. Ion and electron beam assisted growth of nanometric SimOn structures for near-field microscopy

    E-Print Network [OSTI]

    Xie, Xiaoliang Sunney

    Ion and electron beam assisted growth of nanometric SimOn structures for near-field microscopy E. J-field optical probes by both ion beam and electron beam assisted deposition techniques IBAD and EBAD . The ion beam provides a higher SimOn growth rate than the electron beam, though the undesirable implantation

  10. Beamed neutron emission driven by laser accelerated light ions

    E-Print Network [OSTI]

    S. Kar; A. Green; H. Ahmed; A. Alejo; A. P. L. Robinson; M. Cerchez; R. Clarke; D. Doria; S. Dorkings; J. Fernandez; S. R. Mirfyazi; P. McKenna; K. Naughton; D. Neely; P. Norreys; C. Peth; H. Powell; J. A. Ruiz; J. Swain; O. Willi; M. Borghesi

    2015-07-16

    We report on the experimental observation of beam-like neutron emission with peak flux of the order of 10^9 n/sr, from light nuclei reactions in a pitcher-catcher scenario, by employing MeV ions driven by high power laser. The spatial profile of the neutron beam, fully captured for the first time by employing a CR39 nuclear track detector, shows a FWHM divergence angle of 70 degrees, with a peak flux nearly an order of magnitude higher than the isotropic component elsewhere. The observed beamed flux of neutrons is highly favourable for a wide range of applications, and indeed for further transport and moderation to thermal energies. A systematic study employing various combinations of pitcher-catcher materials indicates the dominant reactions being d(p, n+p)^1H and d(d,n)^3He. Albeit insufficient cross-section data are available for modelling, the observed anisotropy in the neutrons' spatial and spectral profiles are most likely related to the directionality and high energy of the projectile ions.

  11. Beamed neutron emission driven by laser accelerated light ions

    E-Print Network [OSTI]

    Kar, S; Ahmed, H; Alejo, A; Robinson, A P L; Cerchez, M; Clarke, R; Doria, D; Dorkings, S; Fernandez, J; Mirfyazi, S R; McKenna, P; Naughton, K; Neely, D; Norreys, P; Peth, C; Powell, H; Ruiz, J A; Swain, J; Willi, O; Borghesi, M

    2015-01-01

    We report on the experimental observation of beam-like neutron emission with peak flux of the order of 10^9 n/sr, from light nuclei reactions in a pitcher-catcher scenario, by employing MeV ions driven by high power laser. The spatial profile of the neutron beam, fully captured for the first time by employing a CR39 nuclear track detector, shows a FWHM divergence angle of 70 degrees, with a peak flux nearly an order of magnitude higher than the isotropic component elsewhere. The observed beamed flux of neutrons is highly favourable for a wide range of applications, and indeed for further transport and moderation to thermal energies. A systematic study employing various combinations of pitcher-catcher materials indicates the dominant reactions being d(p, n+p)^1H and d(d,n)^3He. Albeit insufficient cross-section data are available for modelling, the observed anisotropy in the neutrons' spatial and spectral profiles are most likely related to the directionality and high energy of the projectile ions.

  12. Ponderomotive self-focusing of Gaussian laser beam in warm collisional plasma

    SciTech Connect (OSTI)

    Jafari Milani, M. R.; Niknam, A. R.; Farahbod, A. H.

    2014-06-15

    The propagation characteristics of a Gaussian laser beam through warm collisional plasma are investigated by considering the ponderomotive force nonlinearity and the complex eikonal function. By introducing the dielectric permittivity of warm unmagnetized plasma and using the WKB and paraxial ray approximations, the coupled differential equations defining the variations of laser beam parameters are obtained and solved numerically. Effects of laser and plasma parameters such as the collision frequency, the initial laser intensity and its spot size on the beam width parameter and the axis laser intensity distribution are analyzed. It is shown that, self-focusing of the laser beam takes place faster by increasing the collision frequency and initial laser spot size and then after some distance propagation the laser beam abruptly loses its initial diameter and vastly diverges. Furthermore, the modified electron density distribution is obtained and the collision frequency effect on this distribution is studied.

  13. 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)

    2012-10-15

    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.

  14. Energy dependence of the ripple wavelength for ion-beam sputtering of silicon: Experiments and theory

    E-Print Network [OSTI]

    Cuerno, Rodolfo

    Energy dependence of the ripple wavelength for ion-beam sputtering of silicon: Experiments as a representative case, we study the dependence of the ripple wavelength with the average ion energy, finding or collimated beam of energetic ions (energies being in the 200 eV to 20 keV range) that impinge onto the former

  15. Simulating a Maxwellian plasma using an electron beam ion trap D. W. Savina)

    E-Print Network [OSTI]

    Savin, Daniel Wolf

    Simulating a Maxwellian plasma using an electron beam ion trap D. W. Savina) Columbia Astrophysics for producing a Maxwell­Boltzmann electron energy distribution using an electron beam ion trap EBIT of DR to EIE lines in heliumlike ions is a well understood electron temperature diagnostic

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

    DOE Patents [OSTI]

    Hershcovitch, A.

    1984-02-13

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

  17. Effects of ionization distribution on plasma beam focusing characteristics in Hall thrusters

    SciTech Connect (OSTI)

    Ning Zhongxi; Liu Hui; Yu Daren [Plasma Propulsion Laboratory, Harbin Institute of Technology, Harbin 150001 (China); Zhou Zhongxiang [Department of Physics, Harbin Institute of Technology, Harbin 150001 (China)

    2011-11-28

    The relationship between ionization distribution and divergence of plasma beam in a Hall thruster is investigated using spectrum and probe methods. Experimental results indicate that the shift of ionization region towards the exit of channel causes the reduction of accelerating field and the enhancement of electron thermal pressure effect, which result in further deviation of equipotential lines to magnetic field lines and further increase in divergence of plasma beam. It is, therefore, suggested that to put the ionization region deep inside the channel and separate it from the acceleration region at the design, and development stage is helpful to improve the plasma beam focusing characteristics of a Hall thruster.

  18. Design of titania nanotube structures by focused laser beam direct writing

    SciTech Connect (OSTI)

    Enachi, Mihai [National Center for Materials Study and Testing, Technical University of Moldova, Stefan cel Mare av. 168, Chisinau, MD-2004 (Moldova, Republic of); Stevens-Kalceff, Marion A. [School of Physics, University of New South Wales, Sydney, New South Wales 2052 (Australia); Sarua, Andrei [H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Ursaki, Veaceslav [Institute of Applied Physics, Academy of Sciences of Moldova, Chisinau, MD-2028 (Moldova, Republic of); Tiginyanu, Ion, E-mail: tiginyanu@asm.md [National Center for Materials Study and Testing, Technical University of Moldova, Stefan cel Mare av. 168, Chisinau, MD-2004 (Moldova, Republic of); Institute of Electronic Engineering and Nanotechnologies, Academy of Sciences of Moldova, Chisinau, MD-2028 (Moldova, Republic of)

    2013-12-21

    In this work, we report on electrochemical fabrication of titania films consisting of nanotubes (NTs) and their treatment by focused laser beam. The results of sample characterization by optical and scanning electron microscopy, cathodoluminescence imaging, and Raman scattering scanning spectroscopy are compared to those inherent to specimens subjected to thermal treatment in a furnace. The obtained data demonstrate possibilities for controlling crystallographic structure of TiO{sub 2} NTs by focused laser beam direct writing. These findings open new prospects for the design and fabrication of spatial architectures based on titania nanotubes.

  19. THE DISPERSION RELATIONS AND INSTABILITY THRESHOLDS OF OBLIQUE PLASMA MODES IN THE PRESENCE OF AN ION BEAM

    SciTech Connect (OSTI)

    Verscharen, Daniel; Chandran, Benjamin D. G. E-mail: benjamin.chandran@unh.edu

    2013-02-10

    An ion beam can destabilize Alfven/ion-cyclotron waves and magnetosonic/whistler waves if the beam speed is sufficiently large. Numerical solutions of the hot-plasma dispersion relation have previously shown that the minimum beam speed required to excite such instabilities is significantly smaller for oblique modes with k Multiplication-Sign B {sub 0} {ne} 0 than for parallel-propagating modes with k Multiplication-Sign B {sub 0} = 0, where k is the wavevector and B {sub 0} is the background magnetic field. In this paper, we explain this difference within the framework of quasilinear theory, focusing on low-{beta} plasmas. We begin by deriving, in the cold-plasma approximation, the dispersion relation and polarization properties of both oblique and parallel-propagating waves in the presence of an ion beam. We then show how the instability thresholds of the different wave branches can be deduced from the wave-particle resonance condition, the conservation of particle energy in the wave frame, the sign (positive or negative) of the wave energy, and the wave polarization. We also provide a graphical description of the different conditions under which Landau resonance and cyclotron resonance destabilize Alfven/ion-cyclotron waves in the presence of an ion beam. We draw upon our results to discuss the types of instabilities that may limit the differential flow of alpha particles in the solar wind.

  20. Medical applications of nuclear physics and heavy-ion beams

    SciTech Connect (OSTI)

    Alonso, Jose R.

    2000-08-01

    Isotopes and accelerators, hallmarks of nuclear physics, are finding increasingly sophisticated and effective applications in the medical field. Diagnostic and therapeutic uses of radioisotopes are now a $10B/yr business worldwide, with over 10 million procedures and patient studies performed every year. This paper will discuss the use of isotopes for these applications. In addition, beams of protons and heavy ions are being more and more widely used clinically for treatment of malignancies. To be discussed here as well will be the rationale and techniques associated with charged-particle therapy, and the progress in implementation and optimization of these technologies for clinical use.

  1. Accessing defect dynamics using intense, nanosecond pulsed ion beams

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Persaud, A.; Barnard, J. J.; Guo, H.; Hosemann, P.; Lidia, S.; Minor, A. M.; Seidl, P. A.; Schenkel, T.

    2015-06-18

    Gaining in-situ access to relaxation dynamics of radiation induced defects will lead to a better understanding of materials and is important for the verification of theoretical models and simulations. We show preliminary results from experiments at the new Neutralized Drift Compression Experiment (NDCX-II) at Lawrence Berkeley National Laboratory that will enable in-situ access to defect dynamics through pump-probe experiments. Here, the unique capabilities of the NDCX-II accelerator to generate intense, nanosecond pulsed ion beams are utilized. Preliminary data of channeling experiments using lithium and potassium ions and silicon membranes are shown. We compare these data to simulation results using Crystalmore »Trim. Furthermore, we discuss the improvements to the accelerator to higher performance levels and the new diagnostics tools that are being incorporated.« less

  2. Accessing defect dynamics using intense, nanosecond pulsed ion beams

    SciTech Connect (OSTI)

    Persaud, A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Barnard, J. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Guo, H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hosemann, P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Lidia, S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Minor, A. M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Seidl, P. A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Schenkel, T. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-01-01

    Gaining in-situ access to relaxation dynamics of radiation induced defects will lead to a better understanding of materials and is important for the verification of theoretical models and simulations. We show preliminary results from experiments at the new Neutralized Drift Compression Experiment (NDCX-II) at Lawrence Berkeley National Laboratory that will enable in-situ access to defect dynamics through pump-probe experiments. Here, the unique capabilities of the NDCX-II accelerator to generate intense, nanosecond pulsed ion beams are utilized. Preliminary data of channeling experiments using lithium and potassium ions and silicon membranes are shown. We compare these data to simulation results using Crystal Trim. Furthermore, we discuss the improvements to the accelerator to higher performance levels and the new diagnostics tools that are being incorporated.

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

    DOE Patents [OSTI]

    Hershcovitch, Ady (Mount Sinai, NY)

    1987-01-01

    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.

  4. Electron cloud effects on an intense ion beam in a four solenoid lattice

    E-Print Network [OSTI]

    2008-01-01

    electrons when intercepting the beam with diagnostics. Theon the electron cloud diagnostics for the 45-mA beam andbeam ion and electron species in the vicinity of the diagnostic (

  5. 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.

    2004-01-01

    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-

  6. Production, formation, and transport of high-brightness atomic hydrogen beam studies for the relativistic heavy ion collider polarized source upgrade

    SciTech Connect (OSTI)

    Kolmogorov, A. Stupishin, N.; Atoian, G.; Ritter, J.; Zelenski, A.; Davydenko, V.; Ivanov, A.; Novosibirsk State University, Novosibirsk

    2014-02-15

    The RHIC polarized H{sup ?} ion source had been successfully upgraded to higher intensity and polarization by using a very high brightness fast atomic beam source developed at BINP, Novosibirsk. In this source the proton beam is extracted by a four-grid multi-aperture ion optical system and neutralized in the H{sub 2} gas cell downstream from the grids. The proton beam is extracted from plasma emitter with a low transverse ion temperature of ?0.2 eV which is formed by plasma jet expansion from the arc plasma generator. The multi-hole grids are spherically shaped to produce “geometrical” beam focusing. Proton beam formation and transport of atomic beam were experimentally studied at test bench.

  7. Infrared measurements and simulations of metal meshes in a focused beam

    SciTech Connect (OSTI)

    Stewart, K. P., E-mail: ken.stewart@nrl.navy.mil [Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, DC 20375 (United States); Möller, K. D.; Grebel, H. [Electrical Engineering Department, New Jersey Institute of Technology, Electronic Imaging Center, Newark, New Jersey 07102 (United States)

    2014-02-07

    Infrared transmittance measurements of quasioptical filters are often restricted to a focused beam due to the optical design of the spectrometer. In contrast, numerical simulations assume an incident plane wave, which makes it difficult to compare theory with experimental data. We compare transmittance measurements with numerical simulations of square arrays of circular holes in 3-?m thick Cu sheets at angles of incidence from 0° to 20° for both s and p polarizations. These simple structures allow detailed tests of our electromagnetic simulation methods and show excellent agreement between theory and measurement. Measurements in a focused beam are accurately simulated by combining plane wave calculations over a range of angles that correspond to the focal ratio of the incident beam. Similar screens have been used as components of narrow bandpass filters for far-infrared astronomy, but these results show that the transmittance variations with angle of incidence and polarization limit their use to collimated beams at near normal incidence. The simulations are accurate enough to eliminate a costly trial-and-error approach to the design of more complex and useful quasioptical infrared filters and to predict their in-band performance and out-of-band blocking in focused beams.

  8. Investigation of heat release in the targets during irradiation by ion beams

    E-Print Network [OSTI]

    O. D. Dalkarov; M. A. Negodaev; A. S. Rusetskii

    2015-07-31

    The DD-reaction is investigated and the heat emission off the targets during their irradiation with ion beams is studied at the HELIS ion accelerator at LPI. The heat emission is observed to be significantly higher in the case of irradiation of the Ti/TiO2:Dx-targets by a D+ beam, as compared to the H+ and Ne+ beams. Furthermore, it depends on the concentration of deuterium in the target and current density of the deuteron beam.

  9. Investigation of heat release in the targets during irradiation by ion beams

    E-Print Network [OSTI]

    Dalkarov, O D; Rusetskii, A S

    2015-01-01

    The DD-reaction is investigated and the heat emission off the targets during their irradiation with ion beams is studied at the HELIS ion accelerator at LPI. The heat emission is observed to be significantly higher in the case of irradiation of the Ti/TiO2:Dx-targets by a D+ beam, as compared to the H+ and Ne+ beams. Furthermore, it depends on the concentration of deuterium in the target and current density of the deuteron beam.

  10. 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.; Salamon, K.; Bernstorff, S.

    2012-09-03

    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.

  11. An estimate of collisional beam scattering during final focus in NDCX-II

    SciTech Connect (OSTI)

    Cohen, R.H.

    2010-03-23

    The final focus of NDCX-II contains a region with quite high plasma density. We estimate here how much collisional scatter we expect from transit through this plasma. A separate question, not explored here, is how much scatter there might be off of collective fluctuations in the neutralizing plasma, including those driven by the passage of the beam.

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

    SciTech Connect (OSTI)

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

    2013-03-15

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

  13. Test bench to commission a third ion source beam line and a newly designed extraction system

    SciTech Connect (OSTI)

    Winkelmann, T.; Cee, R.; Haberer, T.; Naas, B.; Peters, A.

    2012-02-15

    The HIT (Heidelberg Ion Beam Therapy Center) is the first hospital-based treatment facility in Europe where patients can be irradiated with protons and carbon ions. Since the commissioning starting in 2006 two 14.5 GHz electron cyclotron resonance ion sources are routinely used to produce a variety of ion beams from protons up to oxygen. In the future a helium beam for regular patient treatment is requested, therefore a third ion source (Supernanogan source from PANTECHNIK S.A.) will be integrated. This third ECR source with a newly designed extraction system and a spectrometer line is installed at a test bench at HIT to commission and validate this section. Measurements with different extraction system setups will be presented to show the improvement of beam quality for helium, proton, and carbon beams. An outlook to the possible integration scheme of the new ion source into the production facility will be discussed.

  14. Energy spectrum of argon ions emitted from Filippov type Sahand plasma focus

    SciTech Connect (OSTI)

    Mohammadnejad, M.; Pestehe, S. J.; Mohammadi, M. A.; Research Institute for Applied Physics and Astronomy, University of Tabriz, Tabriz

    2013-07-15

    The energy and flux of the argon ions produced in Sahand plasma focus have been measured by employing a well-designed Faraday cup. The secondary electron emission effects on the ion signals are simulated and the dimensions of Faraday cup are optimized to minimize these effects. The measured ion energy spectrum is corrected for the ion energy loss and charge exchange in the background gas. The effects of the capacitor bank voltage and working gas pressure on the ion energy spectrum are also investigated. It has been shown that the emitted ion number per energy increases as the capacitor bank voltage increases. Decreasing the working gas pressure leads to the increase in the number of emitted ion per energy.

  15. Improved neutralized compression and focusing of an intense ion beam using a final focus solenoid

    E-Print Network [OSTI]

    J.E., Coleman,

    2010-01-01

    of Science, Office of Fusion Energy Sciences, of the U.S.of Science, Office of Fusion Energy Sciences, of the U.S.

  16. Control of domain wall pinning by localised focused Ga?{sup +} ion irradiation on Au capped NiFe nanowires

    SciTech Connect (OSTI)

    Burn, D. M. Atkinson, D.

    2014-10-28

    Understanding domain wall pinning and propagation in nanowires are important for future spintronics and nanoparticle manipulation technologies. Here, the effects of microscopic local modification of the magnetic properties, induced by focused-ion-beam intermixing, in NiFe/Au bilayer nanowires on the pinning behavior of domain walls was investigated. The effects of irradiation dose and the length of the irradiated features were investigated experimentally. The results are considered in the context of detailed quasi-static micromagnetic simulations, where the ion-induced modification was represented as a local reduction of the saturation magnetization. Simulations show that domain wall pinning behavior depends on the magnitude of the magnetization change, the length of the modified region, and the domain wall structure. Comparative analysis indicates that reduced saturation magnetisation is not solely responsible for the experimentally observed pinning behavior.

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

    SciTech Connect (OSTI)

    Reginald M. Ronningen; Igor Remec

    2010-09-11

    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.

  18. Generation and focusing of electron beams with initial transverse-longitudinal correlation

    SciTech Connect (OSTI)

    Harris, J. R.; Lewellen, J. W.; Poole, B. R.

    2014-10-07

    In charged particle beams, one of the roles played by space charge is to couple the transverse and longitudinal dynamics of the beam. This can lead to very complex phenomena which are generally studied using computer simulations. However, in some cases models based on phenomenological or analytic approximations can provide valuable insight into the system behavior. In this paper, we employ such approximations to investigate the conditions under which all the slices of a space charge dominated electron beam with slowly varying current could be focused to a waist with the same radius and at the same location, independent of slice current, and show that this can be accomplished approximately if the initial transverse-longitudinal correlation introduced onto the beam by the electron gun is chosen to compensate for the transverse-longitudinal correlation introduced onto the beam in the drift section. The validity of our approximations is assessed by use of progressively more realistic calculations. We also consider several design elements of electron guns that affect the initial correlations in the beams they generate.

  19. Improvements for extending the time between maintenance periods for the Heidelberg ion beam therapy center (HIT) ion sources

    SciTech Connect (OSTI)

    Winkelmann, Tim, E-mail: tim.winkelmann@med.uni-heidelberg.de; Cee, Rainer; Haberer, Thomas; Naas, Bernd; Peters, Andreas; Schreiner, Jochen [Heidelberger Ionenstrahl-Therapie Centrum (HIT), D -69120 Heidelberg (Germany)] [Heidelberger Ionenstrahl-Therapie Centrum (HIT), D -69120 Heidelberg (Germany)

    2014-02-15

    The clinical operation at the Heidelberg Ion Beam Therapy Center (HIT) started in November 2009; since then more than 1600 patients have been treated. In a 24/7 operation scheme two 14.5 GHz electron cyclotron resonance ion sources are routinely used to produce protons and carbon ions. The modification of the low energy beam transport line and the integration of a third ion source into the therapy facility will be shown. In the last year we implemented a new extraction system at all three sources to enhance the lifetime of extraction parts and reduce preventive and corrective maintenance. The new four-electrode-design provides electron suppression as well as lower beam emittance. Unwanted beam sputtering effects which typically lead to contamination of the insulator ceramics and subsequent high-voltage break-downs are minimized by the beam guidance of the new extraction system. By this measure the service interval can be increased significantly. As a side effect, the beam emittance can be reduced allowing a less challenging working point for the ion sources without reducing the effective beam performance. This paper gives also an outlook to further enhancements at the HIT ion source testbench.

  20. Comparison of SOFC Cathode Microstructure Quantified using X-ray Nanotomography and Focused Ioni Beam-scanning Electron Microscopy

    SciTech Connect (OSTI)

    G Nelson; W Harris; J Lombardo; J Izzo Jr.; W Chiu; P Tanasini; M Cantoni; J Van herle; C Comninellis; et al.

    2011-12-31

    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.

  1. 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

    2014-09-02

    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.

  2. 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)

    2014-11-15

    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.

  3. Design and operation of a retarding field energy analyzer with variable focusing for space-charge-dominated electron beams

    E-Print Network [OSTI]

    Valfells, Ágúst

    -charge-dominated electron beams Y. Cui, Y. Zou, A. Valfells, M. Reiser, M. Walter, I. Haber, R. A. Kishek, S. Bernal, and P with electron beams of several keV, in which space-charge effects play an important role. A cylindrical focusing, high-energy colliders, free electron lasers, and other applications require high-quality intense beams

  4. Enhanced relativistic self-focusing of Hermite-cosh-Gaussian laser beam in plasma under density transition

    SciTech Connect (OSTI)

    Nanda, Vikas; Kant, Niti, E-mail: nitikant@yahoo.com [Department of Physics, Lovely Professional University, Phagwara 144411, Punjab (India)] [Department of Physics, Lovely Professional University, Phagwara 144411, Punjab (India)

    2014-04-15

    Enhanced and early relativistic self-focusing of Hermite-cosh-Gaussian (HChG) beam in the plasmas under density transition has been investigated theoretically using Wentzel-Kramers-Brillouin and paraxial ray approximation for mode indices m=0,?1,?and?2. The variation of beam width parameter with normalized propagation distance for m=0,?1,?and?2 is reported, and it is observed that strong self-focusing occurs as the HChG beam propagates deeper inside the nonlinear medium as spot size shrinks due to highly dense plasmas and the results are presented graphically. A comparative study between self-focusing of HChG beam in the presence and absence of plasmas density transition is reported. The dependency of beam width parameter on the normalized propagation distance for different values of decentered parameter “b” has also been presented graphically. For m=0?and?1, strong self-focusing is reported for b=1.8, and for m=2?and?b=1.8, beam gets diffracted. The results obtained indicate the dependency of the self-focusing of the HChG beam on the selected values of decentered parameter. Moreover, proper selection of decentered parameter results strong self-focusing of HChG beam. Stronger self-focusing of laser beam is observed due to the presence of plasma density transition which might be very useful in the applications like the generation of inertial fusion energy driven by lasers, laser driven accelerators, etc.

  5. Negative ion beam injection apparatus with magnetic shield and electron removal means

    DOE Patents [OSTI]

    Anderson, Oscar A. (Berkeley, CA); Chan, Chun F. (Hayward, CA); Leung, Ka-Ngo (Hercules, CA)

    1994-01-01

    A negative ion source is constructed to produce H.sup.- ions without using Cesium. A high percentage of secondary electrons that typically accompany the extracted H.sup.- are trapped and eliminated from the beam by permanent magnets in the initial stage of acceleration. Penetration of the magnetic field from the permanent magnets into the ion source is minimized. This reduces the destructive effect the magnetic field could have on negative ion production and extraction from the source. A beam expansion section in the extractor results in a strongly converged final beam.

  6. 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)

    2014-10-15

    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.

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

    E-Print Network [OSTI]

    2004-01-01

    Electron beam diagnostic for space charge measurement of annon-perturbing electron beam diagnostic system for measuringnon intercepting electron beam diagnostic system consists of

  8. Electron-beam diagnostic for space-charge measurement of an ion beam

    E-Print Network [OSTI]

    2003-01-01

    76, 023301 (2005) Electron-beam diagnostic for space-chargenonperturbing electron-beam diagnostic system for measuring8. (Color online). Electron-beam diagnostic, as installed in

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

    E-Print Network [OSTI]

    2004-01-01

    Electron beam diagnostic for space charge measurement of anAbstract A non-perturbing electron beam diagnostic systemlow energy, low current electron beam is swept transversely

  10. Electron-beam diagnostic for space-charge measurement of an ion beam

    E-Print Network [OSTI]

    2003-01-01

    76, 023301 (2005) Electron-beam diagnostic for space-charge2005) A nonperturbing electron-beam diagnostic system forlow energy, low current electron beam is swept transversely

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

    SciTech Connect (OSTI)

    Buljan, M.; Bogdanovic-Radovic, I.; Karlusic, M.; Desnica, U. V.; Radic, N.; Dubcek, P.; Drazic, G.; Salamon, K.; Bernstorff, S.; Holy, V.

    2009-08-10

    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.

  12. Effect of basic physical parameters to control plasma meniscus and beam halo formation in negative ion sources

    SciTech Connect (OSTI)

    Miyamoto, K. [Naruto University of Education, 748 Nakashima, Takashima, Naruto-cho, Naruto-shi, Tokushima 772-8502 (Japan)] [Naruto University of Education, 748 Nakashima, Takashima, Naruto-cho, Naruto-shi, Tokushima 772-8502 (Japan); Okuda, S.; Nishioka, S.; Hatayama, A. [Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan)] [Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan)

    2013-09-14

    Our previous study shows that the curvature of the plasma meniscus causes the beam halo in the negative ion sources: the negative ions extracted from the periphery of the meniscus are over-focused in the extractor due to the electrostatic lens effect, and consequently become the beam halo. In this article, the detail physics of the plasma meniscus and beam halo formation is investigated with two-dimensional particle-in-cell simulation. It is shown that the basic physical parameters such as the H{sup ?} extraction voltage and the effective electron confinement time significantly affect the formation of the plasma meniscus and the resultant beam halo since the penetration of electric field for negative ion extraction depends on these physical parameters. Especially, the electron confinement time depends on the characteristic time of electron escape along the magnetic field as well as the characteristic time of electron diffusion across the magnetic field. The plasma meniscus penetrates deeply into the source plasma region when the effective electron confinement time is short. In this case, the curvature of the plasma meniscus becomes large, and consequently the fraction of the beam halo increases.

  13. White Paper on Ion Beam Transport for ICF: Issues, R&D Need,and Tri-Lab Plans

    SciTech Connect (OSTI)

    Olson, C.; Lee, E.; Langdon, B.

    2005-05-04

    To date, most resources for ion beam fusion have been devoted to development of accelerators and target physics; relatively few resources have gone into ion beam transport development. Because of theoretical studies and substantial experience with electron beam transport, the ion beam transport community is now poised to develop and optimize ion beam transport for ICF. Because of this Tri-Lab effort, a path for coordinated development of ion beam transport has been established. The rate of progress along this path will now be determined largely by the availability of resources.

  14. AN INTENSE NON-RELATIVISTIC CESIUM ION BEAM

    E-Print Network [OSTI]

    Lampel, M.C.

    2010-01-01

    Cesium Injector Electron Beam Probe The Diagnostic Tank and2.3, the diagnostic tank containing the electron beam probe,An electron beam probe was developed as the major diagnostic

  15. Intense Ion Beam for Warm Dense Matter Physics

    E-Print Network [OSTI]

    Heimbucher, Lynn

    2008-01-01

    Apertured beam measurements with electron cloud diagnosticsdiagnostic to measure beam induced gas desorption, ionization, and electronon the electron cloud diagnostics for the 45-mA beam and the

  16. 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)

    2013-07-03

    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.

  17. An Ion Guide for the Production of a Low Energy Ion Beam of Daughter Products of $?$-Emitters

    E-Print Network [OSTI]

    B. Tordoff; T. Eronen; V. V. Elomaa; S. Gulick; U. Hager; P. Karvonen; T. Kessler; J. Lee; I. Moore; A. Popov; S. Rahaman; S. Rinta-Antila; T. Sonoda; J. Aysto

    2006-05-22

    A new ion guide has been modeled and tested for the production of a low energy ($\\approx$ 40 kV) ion beam of daughter products of alpha-emitting isotopes. The guide is designed to evacuate daughter recoils originating from the $\\alpha$-decay of a $^{233}$U source. The source is electroplated onto stainless steel strips and mounted along the inner walls of an ion guide chamber. A combination of electric fields and helium gas flow transport the ions through an exit hole for injection into a mass separator. Ion guide efficiencies for the extraction of $^{229}$Th$^{+}$ (0.06%), $^{221}$Fr$^{+}$ (6%), and $^{217}$At$^{+}$ (6%) beams have been measured. A detailed study of the electric field and gas flow influence on the ion guide efficiency is described for two differing electric field configurations.

  18. Fast-ion-beam photoelectron spectrometer K. A. Hanold, C. R. Sherwood, M. C. Garner, and R. E. Continetti

    E-Print Network [OSTI]

    Continetti, Robert E.

    Fast-ion-beam photoelectron spectrometer K. A. Hanold, C. R. Sherwood, M. C. Garner, and R. E) A high-collection-efficiency fast-ion-beam photoelectron spectrometer is described. In a straight time of the photoelectron laboratory energy to center-of-mass energy. The fast-ion-beam photoelectron spectrometer is used

  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.

    1999-11-05

    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. 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)

    2012-07-11

    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.

  1. Generation of Low Absolute Energy Spread Electron Beams in Laser Wakefield Acceleration Using Tightly Focused Laser through Near-Ionization-Threshold Injection

    E-Print Network [OSTI]

    Li, F; Wan, Y; Wu, Y P; Hua, J F; Pai, C H; Lu, W; Mori, W B; Joshi, C

    2015-01-01

    An enhanced ionization injection scheme using a tightly focused laser pulse with intensity near the ionization potential to trigger the injection process in a mismatched pre-plasma channel has been proposed and examined via multi-dimensional particle-in-cell simulations. The core idea of the proposed scheme is to lower the energy spread of trapped beams by shortening the injection distance. We have established theory to precisely predict the injection distance, as well as the ionization degree of injection atoms/ions, electron yield and ionized charge. We have found relation between injection distance and laser and plasma parameters, giving a strategy to control injection distance hence optimizing beam's energy spread. In the presented simulation example, we have investigated the whole injection and acceleration in detail and found some unique features of the injection scheme, like multi-bunch injection, unique longitudinal phase-space distribution, etc. Ultimate electron beam has a relative energy spread (rm...

  2. Strong self-focusing of a cosh-Gaussian laser beam in collisionless magneto-plasma under plasma density ramp

    SciTech Connect (OSTI)

    Nanda, Vikas; Kant, Niti

    2014-07-15

    The effect of plasma density ramp on self-focusing of cosh-Gaussian laser beam considering ponderomotive nonlinearity is analyzed using WKB and paraxial approximation. It is noticed that cosh-Gaussian laser beam focused earlier than Gaussian beam. The focusing and de-focusing nature of the cosh-Gaussian laser beam with decentered parameter, intensity parameter, magnetic field, and relative density parameter has been studied and strong self-focusing is reported. It is investigated that decentered parameter “b” plays a significant role for the self-focusing of the laser beam as for b=2.12, strong self-focusing is seen. Further, it is observed that extraordinary mode is more prominent toward self-focusing rather than ordinary mode of propagation. For b=2.12, with the increase in the value of magnetic field self-focusing effect, in case of extraordinary mode, becomes very strong under plasma density ramp. Present study may be very useful in the applications like the generation of inertial fusion energy driven by lasers, laser driven accelerators, and x-ray lasers. Moreover, plasma density ramp plays a vital role to enhance the self-focusing effect.

  3. 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)

    2013-07-18

    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.

  4. Heavy Ion Beams for Investigation of Thermophysical Properties

    E-Print Network [OSTI]

    Igor Iosilevskiy

    2010-05-23

    Perspectives for study of thermophysical properties via uniform quasi-stationary volumetric heating under Heavy Ion Beam (HIB) heating with moderate but realistic energy deposition (~ 1 kJ/g) are under discussion. New quasi-isobaric regime of heating is proposed as combination of the HIB energy deposition with the use of highly dispersed porous material as an irradiating sample. Regime of "tracing saturation curve" is proposed also when heating the evaporating porous materials. Consequent preferences and priorities are emphasized. In frames of this technique HIB could became an uncompetitive tool for study of phase transition phenomenon for a wide number of materials with high-temperature location of critical point. Two important thermophysical problems, which could approve using of HIB facility, are discussed as the first-row candidates. Evaporation in Uranium is one of the most tempting candidates to be studied under HIB heating in such manner. When being successful this experiment has a good chance to resolve the old contradiction within the problem of Uranium critical point parameters estimations. The heating by HIB seems to be especially promising as an effective tool for systematic study of so-called "non-congruent" phase transition -- striking and mostly unusual sort of high-temperature phase equilibrium in chemically active strongly coupled plasmas. Phase transition in uranium dioxide is remarkable example of such non-congruency. New information on the thermophysical properties of phase transitions in uranium and uranium dioxide could be valuable for application in nuclear reactor safety analysis

  5. Direct reaction measurements with a 132Sn radioactive ion beam

    E-Print Network [OSTI]

    K. L. Jones; A. S. Adekola; D. W. Bardayan; J. C. Blackmon; K. Y. Chae; K. A. Chipps; J. A. Cizewski; L. Erikson; C. Harlin; R. Hatarik; R. Kapler; R. L. Kozub; J. F. Liang; R. Livesay; Z. Ma; B. H. Moazen; C. D. Nesaraja; F. M. Nunes; S. D. Pain; N. P. Patterson; D. Shapira; J. F. Shriner Jr; M. S. Smith; T. P. Swan; J. S. Thomas

    2011-05-24

    The (d,p) neutron transfer and (d,d) elastic scattering reactions were measured in inverse kinematics using a radioactive ion beam of 132Sn at 630 MeV. The elastic scattering data were taken in a region where Rutherford scattering dominated the reaction, and nuclear effects account for less than 8% of the cross section. The magnitude of the nuclear effects was found to be independent of the optical potential used, allowing the transfer data to be normalized in a reliable manner. The neutron-transfer reaction populated a previously unmeasured state at 1363 keV, which is most likely the single-particle 3p1/2 state expected above the N=82 shell closure. The data were analyzed using finite range adiabatic wave calculations and the results compared with the previous analysis using the distorted wave Born approximation. Angular distributions for the ground and first excited states are consistent with the previous tentative spin and parity assignments. Spectroscopic factors extracted from the differential cross sections are similar to those found for the one neutron states beyond the benchmark doubly-magic nucleus 208Pb.

  6. Optical trapping and rotation of airborne absorbing particles with a single focused laser beam

    SciTech Connect (OSTI)

    Lin, Jinda; Li, Yong-qing, E-mail: liy@ecu.edu [Department of Physics, East Carolina University, Greenville, North Carolina 27858-4353 (United States)] [Department of Physics, East Carolina University, Greenville, North Carolina 27858-4353 (United States)

    2014-03-10

    We measure the periodic circular motion of single absorbing aerosol particles that are optically trapped with a single focused Gaussian beam and rotate around the laser propagation direction. The scattered light from the trapped particle is observed to be directional and change periodically at 0.4–20?kHz. The instantaneous positions of the moving particle within a rotation period are measured by a high-speed imaging technique using a charge coupled device camera and a repetitively pulsed light-emitting diode illumination. The centripetal acceleration of the trapped particle as high as ?20 times the gravitational acceleration is observed and is attributed to the photophoretic forces.

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

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

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

    2015-12-23

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

  8. Design and characterization of electron beam focusing for X-ray generation in novel medical imaging architecture

    SciTech Connect (OSTI)

    Bogdan Neculaes, V., E-mail: neculaes@research.ge.com; Zou, Yun; Zavodszky, Peter; Inzinna, Louis; Zhang, Xi; Conway, Kenneth; Caiafa, Antonio; Frutschy, Kristopher; Waters, William; De Man, Bruno [GE Global Research, Niskayuna, New York 12309 (United States)] [GE Global Research, Niskayuna, New York 12309 (United States)

    2014-05-15

    A novel electron beam focusing scheme for medical X-ray sources is described in this paper. Most vacuum based medical X-ray sources today employ a tungsten filament operated in temperature limited regime, with electrostatic focusing tabs for limited range beam optics. This paper presents the electron beam optics designed for the first distributed X-ray source in the world for Computed Tomography (CT) applications. This distributed source includes 32 electron beamlets in a common vacuum chamber, with 32 circular dispenser cathodes operated in space charge limited regime, where the initial circular beam is transformed into an elliptical beam before being collected at the anode. The electron beam optics designed and validated here are at the heart of the first Inverse Geometry CT system, with potential benefits in terms of improved image quality and dramatic X-ray dose reduction for the patient.

  9. Laser damage resistance of hafnia thin films deposited by electron beam deposition, reactive low voltage ion plating, and dual ion beam sputtering

    SciTech Connect (OSTI)

    Gallais, Laurent; Capoulade, Jeremie; Natoli, Jean-Yves; Commandre, Mireille; Cathelinaud, Michel; Koc, Cian; Lequime, Michel

    2008-05-01

    A comparative study is made of the laser damage resistance of hafnia coatings deposited on fused silica substrates with different technologies: electron beam deposition (from Hf or HfO2 starting material), reactive low voltage ion plating, and dual ion beam sputtering.The laser damage thresholds of these coatings are determined at 1064 and 355 nm using a nanosecond pulsed YAG laser and a one-on-one test procedure. The results are associated with a complete characterization of the samples: refractive index n measured by spectrophotometry, extinction coefficient k measured by photothermal deflection, and roughness measured by atomic force microscopy.

  10. Space Debris Removal with an Ion Beam Shepherd Satellite: target-plasma interaction

    E-Print Network [OSTI]

    Carlos III de Madrid, Universidad

    of the force and torque exerted upon the target debris, and (3) a preliminary evaluation of other plasma the complexity, costs and risks of an active removal campaign. The idea is based on an Ion Beam Shepherd (IBS

  11. Resolution Improvement and Pattern Generator Development for the Maskless Micro-Ion-Beam Reduction Lithography System

    E-Print Network [OSTI]

    Jiang, Ximan

    2006-01-01

    ion beam energy…………………………..66 MMRL optics column relies onElectron optics using multipole lenses for a low energybeam energy is 30eV, because the original MMRL optics column

  12. Long time simulation of a beam in a periodic focusing channel via a two-scale PIC-method

    E-Print Network [OSTI]

    Frénod, Emmanuel

    Long time simulation of a beam in a periodic focusing channel via a two-scale PIC-method E. Fr. Keywords: Vlasov-Poisson system, kinetic equations, homogenization, two-scale convergence, two- scale PIC

  13. Study of nonlinear ohmic heating and ponderomotive force effects on the self-focusing and defocusing of Gaussian laser beams in collisional underdense plasmas

    SciTech Connect (OSTI)

    Etehadi Abari, M.; Shokri, B. [Physics Department and Laser-Plasma Research Institute of Shahid Beheshti University, G.C., Evin, Tehran (Iran, Islamic Republic of)

    2012-11-15

    In the present paper, the propagation characteristics of a linearly polarized gaussian laser beam in a non-isothermal underdense collisional plasma is studied. By considering the effects of the ponderomotive force and ohmic heating of plasma electrons as the nonlinear mechanisms, the second order differential equation of the dimensionless beam width parameter has been obtained and solved at several initial ion temperatures. Furthermore, by using the nonlinear dielectric permittivity of the mentioned plasma medium in the paraxial approximation and its dependence on the propagation characteristics of the gaussian laser pulse, the perturbed electron density n{sub e}/n{sub 0e} is obtained and its variation in terms of the dimensionless plasma length is analyzed at different initial ion temperatures. Our results show that the dimensionless beam width parameter is strongly influenced by the initial plasma ion temperature. It is found that, for the self-focusing regime, the plasma electron density perturbation continuously oscillates between the initial density distribution and a minimum, and for the defocusing regime, the plasma electron density perturbation continuously oscillates between the initial density distribution and a maximum.

  14. Ion beam synthesis of SiGe alloy layers

    SciTech Connect (OSTI)

    Im, Seongil

    1994-05-01

    Procedures required for minimizing structural defects generated during ion beam synthesis of SiGe alloy layers were studied. Synthesis of 200 mm SiGe alloy layers by implantation of 120-keV Ge ions into <100> oriented Si wafers yielded various Ge peak concentrations after the following doses, 2{times}10{sup 16}cm{sup {minus}2}, 3{times}10{sup 16}cm{sup {minus}2} (mid), and 5{times}10{sup 16}cm{sup {minus}2} (high). Following implantation, solid phase epitaxial (SPE) annealing in ambient N2 at 800C for 1 hr. resulted in only slight redistribution of the Ge. Two kinds of extended defects were observed in alloy layers over 3{times}l0{sup 16}cm{sup {minus}2}cm dose at room temperature (RT): end-of-range (EOR) dislocation loops and strain-induced stacking faults. Density of EOR dislocation loops was much lower in alloys produced by 77K implantation than by RT implantation. Decreasing the dose to obtain 5 at% peak Ge concentration prevents strain relaxation, while those SPE layers with more than 7 at% Ge peak show high densities of misfit- induced stacking faults. Sequential implantation of C following high dose Ge implantation (12 at% Ge peak concentration in layer) brought about a remarkable decrease in density of misfit-induced stacking faults. For peak implanted C > 0.55 at%, stacking fault generation in the epitaxial layer was suppressed, owing to strain compensation by C atoms in the SiGe lattice. A SiGe alloy layer with 0.9 at% C peak concentration under a 12 at% Ge peak exhibited the best microstructure. Results indicate that optimum Ge/C ratio for strain compensation is between 11 and 22. The interface between amorphous and regrown phases (a/c interface) had a dramatic morphology change during its migration to the surface. Initial <100> planar interface decomposes into a <111> faceted interface, changing the growth kinetics; this is associated with strain relaxation by stacking fault formation on (111) planes in the a/c interface.

  15. Saturation of multi-laser beams laser-plasma instabilities from stochastic ion heating

    SciTech Connect (OSTI)

    Michel, P.; Williams, E. A.; Divol, L.; Berger, R. L.; Glenzer, S. H.; Callahan, D. A. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)] [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Rozmus, W. [Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G2G7 (Canada) [Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G2G7 (Canada); Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)

    2013-05-15

    Cross-beam energy transfer (CBET) has been used as a tool on the National Ignition Facility (NIF) since the first energetics experiments in 2009 to control the energy deposition in ignition hohlraums and tune the implosion symmetry. As large amounts of power are transferred between laser beams at the entrance holes of NIF hohlraums, the presence of many overlapping beat waves can lead to stochastic ion heating in the regions where laser beams overlap [P. Michel et al., Phys. Rev. Lett. 109, 195004 (2012)]. This increases the ion acoustic velocity and modifies the ion acoustic waves’ dispersion relation, thus reducing the plasma response to the beat waves and the efficiency of CBET. This pushes the plasma oscillations driven by CBET in a regime where the phase velocities are much smaller than both the electron and ion thermal velocities. CBET gains are derived for this new regime and generalized to the case of multi ion species plasmas.

  16. Self-focusing of a Hermite-cosh Gaussian laser beam in a magnetoplasma with ramp density profile

    SciTech Connect (OSTI)

    Nanda, Vikas; Kant, Niti; Wani, Manzoor Ahmad [Department of Physics, Lovely Professional University, Phagwara 144411, Punjab (India)] [Department of Physics, Lovely Professional University, Phagwara 144411, Punjab (India)

    2013-11-15

    The early and strong self-focusing of a Hermite-cosh-Gaussian laser beam in magnetoplasma in the presence of density ramp has been observed. Focusing and de-focusing nature of the Hermite-cosh-Gaussian laser beam with decentered parameter and magnetic field has been studied, and strong self-focusing is reported. It is investigated that decentered parameter 'b' plays a significant role for the self-focusing of the laser beam and is very sensitive as in case of extraordinary mode. For mode indices, m = 0, 1, 2,?and?b = 4.00, 3.14,?and?2.05, strong self-focusing is observed. Similarly in case of ordinary mode, for m = 0, 1, 2?and?b = 4.00, 3.14, 2.049, respectively, strong self-focusing is reported. Further, it is seen that extraordinary mode is more prominent toward self-focusing rather than ordinary mode of propagation. For mode indices m = 0, 1,?and?2, diffraction term becomes more dominant over nonlinear term for decentered parameter b=0. For selective higher values of decentered parameter in case of mode indices m=0, 1,?and?2, self-focusing effect becomes strong for extraordinary mode. Also increase in the value of magnetic field enhances the self-focusing ability of the laser beam, which is very useful in the applications like the generation of inertial fusion energy driven by lasers, laser driven accelerators, and x-ray lasers.

  17. The neutral hydrogen beam experiment in the Columbia High Beta Tokamak ``HBT``. Part 1, The design of the beam system: Part 2, The orbit simulation of fast ions

    SciTech Connect (OSTI)

    Wang, Jian-Hua; Marshall, T.C.

    1991-12-01

    This report discusses the design of the beam system and the orbit simulation of fast ions in the Columbia High Beat Tokamak. (LSP).

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

    SciTech Connect (OSTI)

    Wiebold, Matt; Sung, Yung-Ta; Scharer, John E.

    2011-06-15

    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}.

  19. Dynamic Faraday cup signal analysis and the measurement of energetic ions emitted by plasma focus

    SciTech Connect (OSTI)

    Pestehe, S. J. Mohammadnejad, M.; Research Institute for Applied Physics and Astronomy, University of Tabriz, Tabriz ; Irani Mobaraki, S.

    2014-03-15

    A theoretical model is developed to study the signals from a typical dynamic Faraday cup, and using this model the output signals from this structure are obtained. A detailed discussion on the signal structure, using different experimental conditions, is also given. It is argued that there is a possibility of determining the total charge of the generated ion pulse, the maximum velocity of the ions, ion velocity distribution, and the number of ion species for mixed working gases, under certain conditions. In addition, the number of different ionization stages, the number of different pinches in one shot, and the number of different existing acceleration mechanisms can also be determined provided that the mentioned conditions being satisfied. An experiment is carried out on the Filippov type 90?kJ Sahand plasma focus using Ar as the working gas at the pressure of 0.25?Torr. The data from a typical shot are fitted to a signal from the model and the total charge of the related energetic ion pulse is deduced using the values of the obtained fit parameters. Good agreement between the obtained amount of the total charge and the values obtained during other experiments on the same plasma focus device is observed.

  20. 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)

    2014-06-15

    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.

  1. INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMS

    E-Print Network [OSTI]

    Sharp, W. M.

    2011-01-01

    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

  2. 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)

    2013-01-14

    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.

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

    E-Print Network [OSTI]

    High energy heavy ion jets emerging from laser plasma generated by long pulse laser beams from, Darmstadt, Germany 2 GSI, Darmstadt, Germany 3 Université de Provence et CNRS, Marseille, France 4, Albuquerque, New Mexico. ~Received 21 February 2005; Accepted 20 April 2005! Abstract High energy heavy ions

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

    SciTech Connect (OSTI)

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

    2014-02-15

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

  5. Measurement of beam characteristics from C{sup 6+} laser ion source

    SciTech Connect (OSTI)

    Yamaguchi, A. Sako, K.; Sato, K.; Hayashizaki, N.; Hattori, T.

    2014-02-15

    We developed a C{sup 6+} laser ion source for a heavy-ion accelerator. A carbon target was irradiated with a Q-switched Nd:YAG laser (1064 nm wavelength, 1.4 J maximum laser energy, 10 ns pulse duration) to generate a high-density plasma. The laser ion source employed a rotating carbon target for continuous operation. Ion beams were extracted from the plasma through a drift space using a direct plasma injection scheme [B. Yu. Sharkov, A. V. Shumshurov, V. P. Dubenkow, O. B. Shamaev, and A. A. Golubev, Rev. Sci. Instrum. 63, 2841 (1992)] up to a maximum voltage of 40 kV. We measured the characteristics of the ion beams from the laser ion source and present the results of experiments here.

  6. 468 IEEE ELECTRON DEVICE LETTERS, VOL. EDL-7, NO. 8, AUGUST 1986 Low-Energy Ion Beam Oxidation of Silicon

    E-Print Network [OSTI]

    Fossum, Eric R.

    468 IEEE ELECTRON DEVICE LETTERS, VOL. EDL-7, NO. 8, AUGUST 1986 Low-Energy Ion Beam Oxidation and neutralized by a thermionic filament whose electron emission is adjusted to yield a net neutral beam of Silicon Abstract-A low-energyoxygen ion beam with energy below 100 eV has been applied to the oxidation

  7. 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.; Assmann, R.; Kabantsev, A.

    2010-06-01

    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.

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

    E-Print Network [OSTI]

    Henestroza, E.

    2012-01-01

    kinematic manipulator", or hexapod. Our current targetarm with a manually adjustable hexapod on top. A long vacuumchamber. The miniature hexapod and the beam diagnostics must

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

    E-Print Network [OSTI]

    Bieniosek, F.M.

    2008-01-01

    kinematic manipulator", or hexapod. Our current targetarm with a manually adjustable hexapod on top. A long vacuumchamber. The miniature hexapod and the beam diagnostics must

  10. Design Requirements and Options for Final Focusing Superconducting Magnets of Heavy Ion Drivers

    SciTech Connect (OSTI)

    Bromberg, L. [MIT Plasma Science and Fusion Center (United States)

    2004-11-15

    The environment close to the chamber of heavy ion inertial fusion energy reactors imposes severe constraints on magnets used for final focusing magnets. Space is at a premium, requiring close proximity of adjacent magnets, making magnet integration imperative. In addition, the high radiation flux imposes stringent shielding requirements. In this paper, the options for final focusing magnet topologies are described. Implications of using both high-temperature superconductors and conventional low-temperature superconductors are investigated. The use of high-temperature superconducting materials may offer an attractive, although speculative, opportunity for a fundamentally different approach to magnet construction, leading to either lower cost or reduced maintenance.

  11. 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

    2013-04-19

    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.

  12. Turning point temperature and competition between relativistic and ponderomotive effects in self-focusing of laser beam in plasma

    SciTech Connect (OSTI)

    Bokaei, B.; Niknam, A. R.; Jafari Milani, M. R.

    2013-10-15

    The propagation characters of Gaussian laser beam in collisionless plasma are investigated by considering the ponderomotive and relativistic nonlinearities. The second-order differential equation of dimensionless beam width parameter is solved numerically, taking into account the effect of electron temperature. The results show that the ponderomotive force does not facilitate the relativistic self-focusing in all intensity ranges. In fact, there exists a certain intensity value that, if below this value, the ponderomotive nonlinearity can contribute to the relativistic self-focusing, or obstruct it, if above. It is also indicated that there is a temperature interval in which self-focusing can occur, while the beam diverges outside of this region. In addition, the results represent the existence of a “turning point temperature” in the mentioned interval that the self-focusing has the strongest power. The value of the turning point is dependent on laser intensity in which higher intensities result in higher turning point.

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

    SciTech Connect (OSTI)

    Wang, Lanfa; Pivi, Mauro; /SLAC

    2012-05-30

    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.

  14. 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)

    2014-10-15

    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.

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

    E-Print Network [OSTI]

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

    2012-01-01

    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 ...

  16. 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)

    2014-02-15

    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.

  17. Means and method for the focusing and acceleration of parallel beams of charged particles

    DOE Patents [OSTI]

    Maschke, Alfred W. (East Moriches, NY)

    1983-07-05

    A novel apparatus and method for focussing beams of charged particles comprising planar arrays of electrostatic quadrupoles. The quadrupole arrays may comprise electrodes which are shared by two or more quadrupoles. Such quadrupole arrays are particularly adapted to providing strong focussing forces for high current, high brightness, beams of charged particles, said beams further comprising a plurality of parallel beams, or beamlets, each such beamlet being focussed by one quadrupole of the array. Such arrays may be incorporated in various devices wherein beams of charged particles are accelerated or transported, such as linear accelerators, klystron tubes, beam transport lines, etc.

  18. ION-MOLECULE INTERACTIONS IN CROSSED-BEAMS

    E-Print Network [OSTI]

    Hansen, Steven George

    2010-01-01

    stripping velocity then, assuming the reaction is a simple Hof-mass velocity, as many ion-molecule reactions do, then Qof-mass velocity than will those of exoergic reactions. An

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

    DOE Patents [OSTI]

    Gessert, Timothy A. (Conifer, CO)

    2001-01-01

    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. Emulation of reactor irradiation damage using ion beams

    SciTech Connect (OSTI)

    Was, G. S.; Jiao, Z.; Getto, E.; Sun, K.; Monterrosa, A. M.; Maloy, S. A.; Anderoglu, O.; Sencer, B. H.; Hackett, M.

    2014-06-14

    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 irradiation 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 irradiation establishes the capability of tailoring ion irradiation to emulate the reactor-irradiated microstructure.

  1. Emulation of reactor irradiation damage using ion beams

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Was, G. S.; Jiao, Z.; Getto, E.; Sun, K.; Monterrosa, A. M.; Maloy, S. A.; Anderoglu, O.; Sencer, B. H.; Hackett, M.

    2014-06-14

    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,more »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 irradiation 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 irradiation establishes the capability of tailoring ion irradiation to emulate the reactor-irradiated microstructure.« less

  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

    2014-10-01

    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. High-intensity ion sources for accelerators with emphasis on H-beam formation and transport

    SciTech Connect (OSTI)

    Keller, Roderich [Los Alamos National Laboratory

    2009-01-01

    This paper lays out the fundamental working principles of a variety of high-current ion sources for accelerators in a tutorial manner, and gives examples of specific source types such as d. c. discharge- and rf-driven multicusp sources. Penning-type and ECR-based sources while discussing those principles, pointing out general performance limits as well as the performance parameters of specific sources. Laser-based, two-chamber-. and surface-ionization sources are briefly mentioned. Main aspects of this review are particle feed. ionization mechanism, beam formation and beam transport. Issues seen with beam formation and low-energy transport of negative hydrogen-ion beams are treated in detail.

  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)

    2014-05-15

    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. Photonic-based laser driven electron beam deflection and focusing structures T. Plettner,* R. L. Byer, and C. McGuinness

    E-Print Network [OSTI]

    Byer, Robert L.

    Photonic-based laser driven electron beam deflection and focusing structures T. Plettner,* R. L, and for beam switching. Generation of beams consisting of electron pulses with sub-fsec duration from laser of other devices that manipulate sub-fsec electron beams. The compactness of the proposed deflection device

  6. Development of a plasma generator for a long pulse ion source for neutral beam injectors

    SciTech Connect (OSTI)

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

    2011-06-15

    A plasma generator for a long pulse H{sup +}/D{sup +} ion source has been developed. The plasma generator was designed to produce 65 A H{sup +}/D{sup +} beams at an energy of 120 keV from an ion extraction area of 12 cm in width and 45 cm in length. Configuration of the plasma generator is a multi-cusp bucket type with SmCo permanent magnets. Dimension of a plasma chamber is 25 cm in width, 59 cm in length, and 32.5 cm in depth. The plasma generator was designed and fabricated at Japan Atomic Energy Agency. Source plasma generation and beam extraction tests for hydrogen coupling with an accelerator of the KSTAR ion source have been performed at the KSTAR neutral beam test stand under the agreement of Japan-Korea collaborative experiment. Spatial uniformity of the source plasma at the extraction region was measured using Langmuir probes and {+-}7% of the deviation from an averaged ion saturation current density was obtained. A long pulse test of the plasma generation up to 200 s with an arc discharge power of 70 kW has been successfully demonstrated. The arc discharge power satisfies the requirement of the beam production for the KSTAR NBI. A 70 keV, 41 A, 5 s hydrogen ion beam has been extracted with a high arc efficiency of 0.9 -1.1 A/kW at a beam extraction experiment. A deuteron yield of 77% was measured even at a low beam current density of 73 mA/cm{sup 2}.

  7. Nanofabrication of Optical Elements for SXR and EUV Applications: Ion Beam Lithography as a New Approach

    SciTech Connect (OSTI)

    Lenz, J. [Institute for X-Optics, RheinAhrCampus Remagen, University of Applied Sciences Koblenz, Suedallee 2, 53424 Remagen (Germany); Research Group Electron Microscopy and Analytics, caesar Research Center, Ludwig-Erhard-Allee 2, 53175 Bonn (Germany); Krupp, N.; Irsen, S. [Research Group Electron Microscopy and Analytics, caesar Research Center, Ludwig-Erhard-Allee 2, 53175 Bonn (Germany); Wilhein, T. [Institute for X-Optics, RheinAhrCampus Remagen, University of Applied Sciences Koblenz, Suedallee 2, 53424 Remagen (Germany)

    2011-09-09

    Diffractive optical elements are important components for applications in soft x-ray and extreme ultraviolet radiation. At present, the standard fabrication method for such optics is based on electron beam lithography followed by nanostructuring. This requires a series of complex processes including exposure, reactive ion-etching, and electro-plating. We report on experiments showing the single-step fabrication of such elements using ion beam lithography. Both transmission and reflection gratings were fabricated and successfully implemented as spectrometers at laboratory soft x-ray sources. Additionally, first steps toward zone plate fabrication are described.

  8. Improvement of a plasma uniformity of the 2nd ion source of KSTAR neutral beam injector

    SciTech Connect (OSTI)

    Jeong, S. H., E-mail: shjeong2@kaeri.re.kr; Kim, T. S.; Lee, K. W.; Chang, D. H.; In, S. R. [Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of)] [Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Bae, Y. S. [National Fusion Research Institute, Daejeon 305-806 (Korea, Republic of)] [National Fusion Research Institute, Daejeon 305-806 (Korea, Republic of)

    2014-02-15

    The 2nd ion source of KSTAR (Korea Superconducting Tokamak Advanced Research) NBI (Neutral Beam Injector) had been developed and operated since last year. A calorimetric analysis revealed that the heat load of the back plate of the ion source is relatively higher than that of the 1st ion source of KSTAR NBI. The spatial plasma uniformity of the ion source is not good. Therefore, we intended to identify factors affecting the uniformity of a plasma density and improve it. We estimated the effects of a direction of filament current and a magnetic field configuration of the plasma generator on the plasma uniformity. We also verified that the operation conditions of an ion source could change a uniformity of the plasma density of an ion source.

  9. Studies on low energy beam transport for high intensity high charged ions at IMP

    SciTech Connect (OSTI)

    Yang, Y. Lu, W.; Fang, X.; University of Chinese Academy of Sciences, Beijing 100039 ; Sun, L. T.; Hu, Q.; Cao, Y.; Feng, Y. C.; Zhang, X. Z.; Zhao, H. W.; Xie, D. Z.

    2014-02-15

    Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou (SECRAL) is an advanced fully superconducting ECR ion source at IMP designed to be operational at the microwave frequency of 18–24 GHz. The existing SECRAL beam transmission line is composed of a solenoid lens and a 110° analyzing magnet. Simulations of particle tracking with 3D space charge effect and realistic 3D magnetic fields through the line were performed using particle-in-cell code. The results of the beam dynamics show that such a low energy beam is very sensitive to the space charge effect and significantly suffers from the second-order aberration of the analyzing magnet resulting in large emittance. However, the second-order aberration could be reduced by adding compensating sextupole components in the beam line. On this basis, a new 110° analyzing magnet with relatively larger acceptance and smaller aberration is designed and will be used in the design of low energy beam transport line for a new superconducting ECR ion source SECRAL-II. The features of the analyzer and the corresponding beam trajectory calculation will be detailed and discussed in this paper.

  10. A Mathematical Devoloped Model for Light Ion Beam Interactions with Plasma

    E-Print Network [OSTI]

    Mirfayzi, S R

    2011-01-01

    Light Ion Beams are providing an efficient system for high energy applications using confinement reaction (ICF). This paper will demonstrate the mathematical properties of ion beams leaving ICF reactors and hitting a solid target. A single Hydrogen heavy nucleus current has been demonstrated using Child-Langmuir in an infinite radius as it leaves the reactor chamber. The maximum energy emission has been recorded by examining the total energy loss of the beam pulse using Bethe-Bloch (dE/dx) where it hits the target and forming plasma. Also the target has been analysed by measuring the induction energy, drift and collision current. A set of formula has been developed for charge and current neutrality, the ion beam is being rotated in azimuthal direction, this induces self-magnetism in this purposes. The concept of self-magnetism Er and Br also has been introduced to the rotating-propagating beam inverse to the beam current through ionized and neutral gas. This has been advanced by developing a set of magnetic f...

  11. Electron-beam-ion-source (EBIS) modeling progress at FAR-TECH, Inc

    SciTech Connect (OSTI)

    Kim, J. S. Zhao, L. Spencer, J. A. Evstatiev, E. G.

    2015-01-09

    FAR-TECH, Inc. has been developing a numerical modeling tool for Electron-Beam-Ion-Sources (EBISs). The tool consists of two codes. One is the Particle-Beam-Gun-Simulation (PBGUNS) code to simulate a steady state electron beam and the other is the EBIS-Particle-In-Cell (EBIS-PIC) code to simulate ion charge breeding with the electron beam. PBGUNS, a 2D (r,z) electron gun and ion source simulation code, has been extended for efficient modeling of EBISs and the work was presented previously. EBIS-PIC is a space charge self-consistent PIC code and is written to simulate charge breeding in an axisymmetric 2D (r,z) device allowing for full three-dimensional ion dynamics. This 2D code has been successfully benchmarked with Test-EBIS measurements at Brookhaven National Laboratory. For long timescale (< tens of ms) ion charge breeding, the 2D EBIS-PIC simulations take a long computational time making the simulation less practical. Most of the EBIS charge breeding, however, may be modeled in 1D (r) as the axial dependence of the ion dynamics may be ignored in the trap. Where 1D approximations are valid, simulations of charge breeding in an EBIS over long time scales become possible, using EBIS-PIC together with PBGUNS. Initial 1D results are presented. The significance of the magnetic field to ion dynamics, ion cooling effects due to collisions with neutral gas, and the role of Coulomb collisions are presented.

  12. Development of a polarized Helium-3 ion source for RHIC using the electron beam ion source

    E-Print Network [OSTI]

    Epstein, Charles Samuel

    2013-01-01

    This thesis presents my work on the design and development of a source of polarized Helium-3 ions for the Relativistic Heavy Ion Collider at Brookhaven National Lab, Upton, NY. The 3He atoms will be polarized using the ...

  13. Ion beam figuring of small optical components Thomas W. Drueding

    E-Print Network [OSTI]

    Bifano, Thomas

    machining system at NASA's Marshall Space Flight Center. This system is designed for processing small (10-cm Flight Center, Alabama 35812 Scott R. Wilson Sandia Systems Incorporated 2655-A PanAmerican Freeway NE provides a method for performing the figuring process with advantages over standard mechanical methods. Ion

  14. 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

  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

    2013-01-01

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

    SciTech Connect (OSTI)

    Roychowdhury, P. Mishra, L.; Kewlani, H.; Mittal, K. C.; Patil, D. S.

    2014-03-15

    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.

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

    E-Print Network [OSTI]

    Jin, J.; Church, David A.

    1994-01-01

    The mean lifetimes tau of the Ca II 4p P-2(1/2) and 4p P-2(3/2) levels, and the Cl-35 II 4p' F-1(3) level, have been measured by a variant of the collinear laser-ion-beam lifetime technique applied previously to the Ar II 4p' F-2(7/2)o level [Jian...

  18. Development of a fast cyclotron gas stopper for intense rare isotope beams from projectile fragmentation: Study of ion extraction with a radiofrequency carpet

    SciTech Connect (OSTI)

    Bollen, Georg; Morrissey, David

    2011-01-16

    Research and development has been performed in support of the design of a future rare isotope beam facility in the US. An important aspect of plans for earlier RIA (Rare Isotope Accelerator) and a requirement of FRIB (Facility of Rare Isotope Beams) to be built at Michigan State University are the availability of so-called “stopped beams” for research that contributes to answering questions like how elements in the universe are created and to provide better insight into the nature of Fundamental Interactions. In order to create “stopped beams” techniques are required that transform fast rare isotopes beams as they are available directly after addresses questions like the origin of that will allow and High priority is given to the evaluation of intensity limitations and the efficiency of stopping of fast fragment beams in gas cells and to the exploration of options to increase the efficiency and the reduction of space charge effects. Systematic studies performed at MSU as part of the RIA R&D with a linear gas cell under conditions close to those expected at RIA and related simulations confirm that the efficiency of stopping and extracting ions decreases with increasing beam intensity. Similar results have also been observed at RIKEN in Japan. These results indicate the concepts presently under study will not be able to cover the full range of intensities of fast beams expected at RIA without major losses. The development of a more robust concept is therefore critical to the RIA concept. Recent new beam simulation studies performed at the NSCL show that the stopping of heavy ions in a weakly focusing gas-filled magnetic field can overcome the intensity limitation of present systems while simultaneously providing a much faster ion extraction. We propose to design and build such a cyclotron gas stopper and to test it at the NSCL under conditions as close as possible to those found at RIA.

  19. 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: cjxiao@pku.edu.cn; Wang, X. G.; Xiao, C. J. E-mail: cjxiao@pku.edu.cn; Wang, L.; Xu, M.

    2014-11-15

    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.

  20. he Ion Beam Materials Laboratory (IBML) is a Los Alamos National Laboratory resource devoted to materi-

    E-Print Network [OSTI]

    he Ion Beam Materials Laboratory (IBML) is a Los Alamos National Laboratory resource devoted Nanotechnologies, a DOE nanoscience center jointly operated by Los Alamos and Sandia National Laboratories. Contact Dr. Yong Q. Wang Materials Science and Technology Division Mail Stop K765 Los Alamos National

  1. Energy distribution and flux of fast neutrals and residual ions extracted from a neutral beam source

    E-Print Network [OSTI]

    Economou, Demetre J.

    Energy distribution and flux of fast neutrals and residual ions extracted from a neutral beam-4004 Received 21 April 2006; accepted 6 July 2006; published 7 August 2006 The energy distribution and flux into fast neutrals. The neutral energy distribution was always shifted to lower energies compared

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

    DOE Patents [OSTI]

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

    2009-05-26

    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.

  3. Corrigendum to: Observation of focusing of 400 GeV/c proton beam with the help of bent crystals [Phys. Lett. B 733 (2014) 366—372

    E-Print Network [OSTI]

    Scandale, W; Butcher, M; Cerutti, F; Gilardoni, S; Lechner, A; Losito, R; Masi, A; Metral, E; Mirarchi, D; Montesano, S; Redaelli, S; Smirnov, G; Bagli, Enrico; Bandiera, L; Baricordi, S; Dalpiaz, P; Guidi, V; Mazzolari, A; Vincenzi, D; Claps, G; Dabagov, S; Hampai, D; Murtas, F; Cavoto, G; Garattini, M; Iacoangeli, F; Ludovici, L; Santacesaria, R; Valente, P; Galluccio, F; Afonin, A G; Chesnokov, Yu A; Chirkov, P N; Maisheev, V A; Sandomirskiy, Yu E; Yazynin, I A; Kovalenko, A D; Taratin, A M; Gavrikov, Yu A; Ivanov, Yu M; Lapina, L P; Ferguson, W; Fulcher, J; Hall, G; Pesaresi, M; Raymond, M

    2014-01-01

    Corrigendum to: Observation of focusing of 400 GeV/c proton beam with the help of bent crystals [Phys. Lett. B 733 (2014) 366—372

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

    SciTech Connect (OSTI)

    Muir, B. R.; Rogers, D. W. O.

    2014-11-01

    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.

  5. Exploring the QCD Phase Structure with Beam Energy Scan in Heavy-ion Collisions

    E-Print Network [OSTI]

    Luo, Xiaofeng

    2016-01-01

    Beam energy scan programs in heavy-ion collisions aim to explore the QCD phase structure at high baryon density. Sensitive observables are applied to probe the signatures of the QCD phase transition and critical point in heavy-ion collisions at RHIC and SPS. Intriguing structures, such as dip, peak and oscillation, have been observed in the energy dependence of various observables. In this paper, an overview is given and corresponding physics implications will be discussed for the experimental highlights from the beam energy scan programs at the STAR, PHENIX and NA61/SHINE experiments. Furthermore, the beam energy scan phase II at RHIC (2019-2020) and other future experimental facilities for studying the physics at low energies will be also discussed.

  6. Exploiting neutron-rich radioactive ion beams to constrain the symmetry energy

    E-Print Network [OSTI]

    Z. Kohley; G. Christian; T. Baumann; P. A. DeYoung; J. E. Finck; N. Frank; M. Jones; J. K. Smith; J. Snyder; A. Spyrou; M. Thoennessen

    2013-10-03

    The Modular Neutron Array (MoNA) and 4 Tm Sweeper magnet were used to measure the free neutrons and heavy charged particles from the radioactive ion beam induced 32Mg + 9Be reaction. The fragmentation reaction was simulated with the Constrained Molecular Dynamics model(CoMD), which demonstrated that the of the heavy fragments and free neutron multiplicities were observables sensitive to the density dependence of the symmetry energy at sub-saturation densities. Through comparison of these simulations with the experimental data constraints on the density dependence of the symmetry energy were extracted. The advantage of radioactive ion beams as a probe of the symmetry energy is demonstrated through examination of CoMD calculations for stable and radioactive beam induced reactions.

  7. Comparative Results on Collimation of the SPS Beam of Protons and Pb Ions with Bent Crystals

    SciTech Connect (OSTI)

    Scandale, W.; Arduini, G.; Assmann, R.; Bracco, C.; Cerutti, F.; Christiansen, J.; Gilardoni, S.; Laface, E.; Losito, R.; Masi, A.; Metral, E.; Mirarchi, D.; Montesano, S.; Previtali, V.; Redaelli, S.; Valentino, G.; Schoofs, P.; Smirnov, G.; Tlustos, L.; Bagli, E.; Baricordi, S.; /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Ferrara U. /Frascati /Frascati /INFN, Legnaro /INFN, Legnaro /INFN, Legnaro /INFN, Legnaro /INFN, Legnaro /INFN, Legnaro /INFN, Rome /INFN, Rome /INFN, Rome /INFN, Rome /INFN, Naples /Serpukhov, IHEP /Serpukhov, IHEP /Serpukhov, IHEP /Serpukhov, IHEP /Serpukhov, IHEP /Dubna, JINR /Dubna, JINR /Dubna, JINR /St. Petersburg, INP /St. Petersburg, INP /St. Petersburg, INP /St. Petersburg, INP /Imperial Coll., London /Imperial Coll., London /Imperial Coll., London /Imperial Coll., London /Imperial Coll., London /Imperial Coll., London /Imperial Coll., London /Imperial Coll., London /Brookhaven /SLAC /SLAC /SLAC

    2012-04-30

    New experiments on crystal assisted collimation have been carried out at the CERN SPS with stored beams of 120 GeV/c protons and Pb ions. Bent silicon crystals of 2 mm long with about 170 {mu}rad bend angle and a small residual torsion were used as primary collimators. In channeling conditions, the beam loss rate induced by inelastic interactions of particles with the crystal nuclei is minimal. The loss reduction was about 6 for protons and about 3 for Pb ions. Lower reduction value for Pb ions can be explained by their considerably larger ionization losses in the crystal. In one of the crystals, the measured fraction of the Pb ion beam halo deflected in channeling conditions was 74%, a value very close to that for protons. The intensity of the off-momentum halo leaking out from the collimation station was measured in the first high dispersion area downstream. The particle population in the shadow of the secondary collimator-absorber was considerably smaller in channeling conditions than for amorphous orientations of the crystal. The corresponding reduction was in the range of 2-5 for both protons and Pb ions.

  8. Particle simulation of collision dynamics for ion beam injection into a rarefied gas

    SciTech Connect (OSTI)

    Giuliano, Paul N.; Boyd, Iain D.

    2013-03-15

    This study details a comparison of ion beam simulations with experimental data from a simplified plasma test cell in order to study and validate numerical models and environments representative of electric propulsion devices and their plumes. The simulations employ a combination of the direct simulation Monte Carlo and particle-in-cell methods representing xenon ions and atoms as macroparticles. An anisotropic collision model is implemented for momentum exchange and charge exchange interactions between atoms and ions in order to validate the post-collision scattering behaviors of dominant collision mechanisms. Cases are simulated in which the environment is either collisionless or non-electrostatic in order to prove that the collision models are the dominant source of low- and high-angle particle scattering and current collection within this environment. Additionally, isotropic cases are run in order to show the importance of anisotropy in these collision models. An analysis of beam divergence leads to better characterization of the ion beam, a parameter that requires careful analysis. Finally, suggestions based on numerical results are made to help guide the experimental design in order to better characterize the ion environment.

  9. 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.; Zhao, H. Y. Zhang, J. J.; Sha, Sh.; Zhang, Zh. L.; Zhang, X. Zh.; Sun, L. T.; Zhao, H. W.

    2014-07-15

    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.

  10. Simulation and optimization of a 10 A electron gun with electrostatic compression for the electron beam ion source

    SciTech Connect (OSTI)

    Pikin, A.; Beebe, E. N.; Raparia, D.

    2013-03-15

    Increasing the current density of the electron beam in the ion trap of the Electron Beam Ion Source (EBIS) in BNL's Relativistic Heavy Ion Collider facility would confer several essential benefits. They include increasing the ions' charge states, and therefore, the ions' energy out of the Booster for NASA applications, reducing the influx of residual ions in the ion trap, lowering the average power load on the electron collector, and possibly also reducing the emittance of the extracted ion beam. Here, we discuss our findings from a computer simulation of an electron gun with electrostatic compression for electron current up to 10 A that can deliver a high-current-density electron beam for EBIS. The magnetic field in the cathode-anode gap is formed with a magnetic shield surrounding the gun electrodes and the residual magnetic field on the cathode is (5 Division-Sign 6) Gs. It was demonstrated that for optimized gun geometry within the electron beam current range of (0.5 Division-Sign 10) A the amplitude of radial beam oscillations can be maintained close to 4% of the beam radius by adjusting the injection magnetic field generated by a separate magnetic coil. Simulating the performance of the gun by varying geometrical parameters indicated that the original gun model is close to optimum and the requirements to the precision of positioning the gun elements can be easily met with conventional technology.

  11. Effect of the plasma electrode position and shape on the beam intensity of the highly charged ions from RIKEN 18 GHz electron-cyclotron-resonance ion source

    SciTech Connect (OSTI)

    Higurashi, Y.; Nakagawa, T.; Kidera, M.; Aihara, T.; Kobayashi, K.; Kase, M.; Goto, A.; Yano, Y. [RIKEN, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan); SAS Ltd. Kita-shinagawa 5-9-11, Shinjuku-ku, Tokyo (Japan); RIKEN, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan)

    2006-03-15

    Beam intensities of highly charged Ar ions (Ar{sup 11+,12+}) were measured as a function of plasma electrode position. We observed that the beam intensity of Ar{sup 11+,12+} increased when putting the electrode far from the electron-cyclotron-resonance zone. On the other hand, lower charged heavy ions (Ar{sup 8+,7+}) dramatically decreased. We observed that the intense beam extraction strongly affects the plasma condition. It may be due to the ion pumping effect.

  12. Beam energy tracking system on Optima XEx high energy ion implanter

    SciTech Connect (OSTI)

    David, Jonathan; Satoh, Shu; Wu Xiangyang; Geary, Cindy; Deluca, James [Axcelis Technologies, Inc., 108 Cherry Hill Dr, Beverly, MA 01915 (United States)

    2012-11-06

    The Axcelis Optima XEx high energy implanter is an RF linac-based implanter with 12 RF resonators for beam acceleration. Even though each acceleration field is an alternating, sinusoidal RF field, the well known phase-focusing principle produces a beam with a sharp quasi-monoenergetic energy spectrum. A magnetic energy filter after the linac further attenuates the low energy continuum in the energy spectrum often associated with RF acceleration. The final beam energy is a function of the phase and amplitude of the 12 resonators in the linac. When tuning a beam, the magnetic energy filter is set to the desired energy, and each linac parameter is tuned to maximize the transmission through the filter. Once a beam is set up, all the parameters are stored in a recipe, which can be easily tuned and has proven to be quite repeatable. The magnetic field setting of the energy filter selects the beam energy from the RF Linac accelerator, and in-situ verification of beam energy in addition to the magnetic energy filter setting has long been desired. An independent energy tracking system was developed for this purpose, using the existing electrostatic beam scanner as a deflector to construct an in-situ electrostatic energy analyzer. This paper will describe the system and performance of the beam energy tracking system.

  13. Clinical output factors for carbon-ion beams passing through polyethylene

    E-Print Network [OSTI]

    Kanematsu, Nobuyuki; Ogata, Risa; Himukai, Takeshi

    2013-01-01

    Purpose: A recent study suggested that polyethylene (PE) range compensators would cause extra carbon-ion attenuation by 0.45%/cm due to limitations in water equivalence. The present study aims to assess its influence on tumor dose in carbon-ion radiotherapy. Methods: Carbon-ion radiation was modeled to be composed of primary carbon ions and secondary particles. For these components, tumor dose fraction and relative biological effectiveness (RBE) were estimated at a reference depth in the middle of spread-out Bragg peak. The PE effect was estimated for clinical carbon-ion beams and was partially tested by experiment. The two-component model was integrated into a treatment-planning system, with which the PE effect on tumor dose was investigated in two clinical cases. Results: The fluence and clinical attenuation coefficients for dose decrease per polyethylene thickness were estimated to be 0.1%-0.3%/cm and 0.2%-0.4%/cm, depending on energy and modulation of clinical carbon-ion beams. In the treatment-planning s...

  14. Determination of the ReA Electron Beam Ion Trap electron beam radius and current density with an X-ray pinhole camera

    SciTech Connect (OSTI)

    Baumann, Thomas M. Lapierre, Alain Kittimanapun, Kritsada; Schwarz, Stefan; Leitner, Daniela; Bollen, Georg

    2014-07-15

    The Electron Beam Ion Trap (EBIT) of the National Superconducting Cyclotron Laboratory at Michigan State University is used as a charge booster and injector for the currently commissioned rare isotope re-accelerator facility ReA. This EBIT charge breeder is equipped with a unique superconducting magnet configuration, a combination of a solenoid and a pair of Helmholtz coils, allowing for a direct observation of the ion cloud while maintaining the advantages of a long ion trapping region. The current density of its electron beam is a key factor for efficient capture and fast charge breeding of continuously injected, short-lived isotope beams. It depends on the radius of the magnetically compressed electron beam. This radius is measured by imaging the highly charged ion cloud trapped within the electron beam with a pinhole camera, which is sensitive to X-rays emitted by the ions with photon energies between 2 keV and 10 keV. The 80%-radius of a cylindrical 800 mA electron beam with an energy of 15 keV is determined to be r{sub 80%}=(212±19)?m in a 4 T magnetic field. From this, a current density of j = (454 ± 83)A/cm{sup 2} is derived. These results are in good agreement with electron beam trajectory simulations performed with TriComp and serve as a test for future electron gun design developments.

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

    SciTech Connect (OSTI)

    Schneider, D. [ed.

    1995-10-01

    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.

  16. High Resolution Ion Mobility Spectrometry with Increased Ion Transmission: Exploring the Analytical Utility of Periodic-Focusing DC Ion Guide Drift Cells 

    E-Print Network [OSTI]

    Blase, Ryan Christopher

    2012-02-14

    Drift tube ion mobility spectrometry (IMS) is a powerful, post-ionization separation that yields structural information of ions through an ion-neutral collision cross section. The ion-neutral collision cross section is governed by the collision...

  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.

    1993-01-01

    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)

    2014-01-14

    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. Uniform heating of materials into the warm dense matter regime with laser-driven quasi-monoenergetic ion beams

    E-Print Network [OSTI]

    Bang, W; Bradley, P A; Vold, E L; Boettger, J C; Fernández, J C

    2015-01-01

    In a recent experiment on the Trident laser facility, a laser-driven beam of quasi-monoenergetic aluminum ions was used to heat solid gold and diamond foils isochorically to 5.5 eV and 1.7 eV, respectively. Here theoretical calculations are presented that suggest the gold and diamond were heated uniformly by these laser-driven ion beams. According to calculations and SESAME equation-of-state tables, laser-driven aluminum ion beams achievable on Trident, with a finite energy spread of (delta E)/E ~ 20%, are expected to heat the targets more uniformly than a beam of 140 MeV aluminum ions with zero energy spread. The robustness of the expected heating uniformity relative to the changes in the incident ion energy spectra is evaluated, and expected plasma temperatures of various target materials achievable with the current experimental platform are presented.

  20. Observation of focusing of 400 GeV/c proton beam with the help of bent crystals

    E-Print Network [OSTI]

    Scandale, W; Butcher, M; Cerutti, F; Gilardoni, S; Lechner, A; Losito, R; Masi, A; Metral, E; Mirarchi, D; Montesano, S; Redaelli, S; Smirnov, G; Bandiera, L; Baricordi, S; Dalpiaz, P; Guidi, V; Mazzolari, A; Vincenzi, D; Claps, G; Dabagov, S; Hampai, D; Murtas, F; Cavoto, G; Garattini, M; Iacoangeli, F; Ludovici, L; Santacesaria, R; Valente, P; Galluccio, F; Afonin, A G; Chesnokov, Yu A; Chirkov, P N; Maisheev, V A; Sandomirskiy, Yu E; Yazynin, I A; Kovalenko, A D; Taratin, A M; Gavrikov, Yu A; Ivanov, Yu M; Lapina, L P; Ferguson, W; Fulcher, J; Hall, G; Pesaresi, M; Raymond, M

    2014-01-01

    The results of observation and studies of focusing of 400 GeV/c proton beam with the help of bent single crystals are presented. Two silicon crystals have been used in the measurements. The focal length of the first and second crystals is found to be 1.48 m and 0.68 m, respectively. The mean square size of the horizontal profile in the focus was 3.1 and 4.3 times as small as at the exit of the crystals.

  1. Temporal Development of Ion Beam Mean Charge State in Pulsed Vacuum Arc Ion Sources

    E-Print Network [OSTI]

    Oks, Efim M.; Yushkov, Georgy Yu.; Anders, Andre

    2008-01-01

    temperature in the vacuum arc plasma and thus higher ioncharged ions in the vacuum arc plasma. The physical aspectsion charge states in vacuum arc plasma were subject of our

  2. Laser-Driven Shock Acceleration of Ion Beams from Spherical Mass-Limited Targets

    SciTech Connect (OSTI)

    Henig, A.; Kiefer, D.; Hoerlein, R.; Major, Zs.; Krausz, F.; Habs, D. [Max-Planck-Institut fuer Quantenoptik, Garching (Germany); Department fuer Physik, Ludwig-Maximilians-Universitaet Muenchen, Garching (Germany); Geissler, M. [Max-Planck-Institut fuer Quantenoptik, Garching (Germany); Department of Physics and Astronomy, Queen's University Belfast, Belfast BT7 1NN (United Kingdom); Rykovanov, S. G. [Max-Planck-Institut fuer Quantenoptik, Garching (Germany); Moscow Physics Engineering Institute, Kashirskoe shosse 31, Moscow (Russian Federation); Ramis, R. [ETSI Aeronauticos, Universidad Politecnica de Madrid (Spain); Osterhoff, J.; Veisz, L.; Karsch, S. [Max-Planck-Institut fuer Quantenoptik, Garching (Germany); Schreiber, J. [Max-Planck-Institut fuer Quantenoptik, Garching (Germany); Department fuer Physik, Ludwig-Maximilians-Universitaet Muenchen, Garching (Germany); Blackett Laboratory, Imperial College, London SW7 2AZ (United Kingdom)

    2009-03-06

    We report on experimental studies of ion acceleration from spherical targets of diameter 15 {mu}m irradiated by ultraintense (1x10{sup 20} W/cm{sup 2}) pulses from a 20-TW Ti:sapphire laser system. A highly directed proton beam with plateau-shaped spectrum extending to energies up to 8 MeV is observed in the laser propagation direction. This beam arises from acceleration in a converging shock launched by the laser, which is confirmed by 3-dimensional particle-in-cell simulations. The temporal evolution of the shock-front curvature shows excellent agreement with a two-dimensional radiation pressure model.

  3. Z-petawatt driven ion beam radiography development.

    SciTech Connect (OSTI)

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

    2013-09-01

    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.

  4. An optical technique for measuring divergence, beam profile, and aiming direction, of relativistic negative hydrogen ions

    SciTech Connect (OSTI)

    Hershcovitch, A.

    1988-02-01

    A novel, nonobstructive diagnostic technique for high energy H/sup minus/D/sup minus/ ion beams is described. This scheme employs spectroscopic techniques designed to measure beam profile, perpendicular velocity spread (i.e., divergence), and orientation of multiMeV H/sup minus/ beams. The basic principle of this method is to photoneutralize a small portion of the H/sup minus/ beam in a way such that the photodetachment process results in the formation of excited hydrogen atoms in the n = 2 levels. Observation of fluorescence from spontaneous decay of H(sp) andor induced deacy of H(2s) can be readily used to determine beam profile. Doppler broadening measurements can be used to determine velocity spread from which beam emittance is calculated. With off-the-shelf instruments resolutions of 1 mm for beam profile and 2 x 10/sup minus/2) ..pi.. cm-mrad are possible. For photodetachment, the best commercially available laser is found to be ArF eximer laser. The analysis is performed for the 200 MEV BNL Linac. The laser, which has a pulse duration which has a pulse duration which is of 10/sup minus/5) of the linac can produce sufficient signal at a negligible beam loss. In addition, measurements of minute Doppler shifts of this Lyman-Alpha radiation by a spectrograph could in principle resolve beam direction to within 1.57 ..mu..rad. The process under consideration has a resonance known as the shape resonance. As the following literature review indicates, the total cross section is known and there is a reasonable agreement between theory and experiment. There are no experimental measurements of partical cross sections. nevertheless, there are theoretical estimates which agree within 15%. 10 refs., 1 fig.

  5. A dynamic focusing x-ray monochromator for a wiggler beam line at the SRS of the SERC Daresbury Laboratory

    SciTech Connect (OSTI)

    De Bruijn, D.; Van Zuylen, P. ); Kruizinga, G. , P.O. Box 93138, 2509 AC Den Haag State University of Utrecht, Sorbonnelaan 16, 3508 TB Utrecht )

    1992-01-01

    A Si(220) double-crystal monochromator for the energy range 10--30 keV is presented. It will be used for EXAFS as well as powder diffraction measurements. To determine the requirements for this monochromator we looked, apart from mean considerations, at the requirements dictated by EXAFS in transmission mode. For good data analyses the proper shape, amplitude, and location at the energy axis of each wiggle is required. Moreover it is essential to separate the wiggles from background and noise. For the latter a high flux through the sample is desirable, which can be achieved by horizontal focusing of the beam. For that we have chosen to bend the second crystal sagitally. The sagittal bending radius is adjustable between 50 and 0.8 m, because for different energies different sagittal radii are necessary to focus the beam on the sample. The mean meridional radius of the second crystal is fixed at 130 m, which is an optimization for 20 keV. The meridional radius of the first crystal can be tuned between 100 and 500 m. When this radius is set to 130 m the energy resolution is calculated to be 6, 3, and 35 eV for 10, 20, and 30 keV (for perfectly bent crystals). By changing the meridional radius of the first crystal, future users of this monochromator can make the trade off between resolution and intensity. Movement of the monochromator exit beam, during a scan, will occur due to the monochromator geometry, but is reduced as much as possible by using an asymmetrically cut second crystal, with an asymmetry angle of 2.5{degree}. The average exit beam movement of the monochromator for a 1-keV scan is 20 {mu}m. For 40% of the energy range (10--30 keV) the exit beam position remains within 10 {mu}m. For the second crystal no translation stage is used.

  6. Arc discharge regulation of a megawatt hot cathode bucket ion source for the experimental advanced superconducting tokamak neutral beam injector

    SciTech Connect (OSTI)

    Xie Yahong; Hu Chundong; Liu Sheng; Jiang Caichao; Li Jun; Liang Lizhen; Collaboration: NBI Team

    2012-01-15

    Arc discharge of a hot cathode bucket ion source tends to be unstable what attributes to the filament self-heating and energetic electrons backstreaming from the accelerator. A regulation method, which based on the ion density measurement by a Langmuir probe, is employed for stable arc discharge operation and long pulse ion beam generation. Long pulse arc discharge of 100 s is obtained based on this regulation method of arc power. It establishes a foundation for the long pulse arc discharge of a megawatt ion source, which will be utilized a high power neutral beam injection device.

  7. Overview of heavy-ion fusion focus on computer simulation aspect

    E-Print Network [OSTI]

    Vay, Jean-Luc

    2002-01-01

    Thermonuclear burn spreads rapidly through the compressed fuel, yielding many times the imput energy Blowoff Radiation The Heavy Ion Fusion

  8. Fast and efficient charge breeding of the Californium rare isotope breeder upgrade electron beam ion source

    SciTech Connect (OSTI)

    Ostroumov, P. N.; Barcikowski, A.; Dickerson, C. A.; Perry, A.; Pikin, A. I.; Sharamentov, S. I.; Vondrasek, R. C.; Zinkann, G. P.

    2015-08-28

    The Electron Beam Ion Source (EBIS), developed to breed Californium Rare Isotope Breeder Upgrade (CARIBU) radioactive beams at Argonne Tandem Linac Accelerator System (ATLAS), is being tested off-line. A unique property of the EBIS is a combination of short breeding times, high repetition rates, and a large acceptance. Overall, we have implemented many innovative features during the design and construction of the CARIBU EBIS as compared to the existing EBIS breeders. The off-line charge breeding tests are being performed using a surface ionization source that produces singly charged cesium ions. The main goal of the off-line commissioning is to demonstrate stable operation of the EBIS at a 10 Hz repetition rate and a breeding efficiency into single charge state higher than 15%. These goals have been successfully achieved and exceeded. We have measured (20% ± 0.7%) breeding efficiency into the single charge state of 28+ cesium ions with the breeding time of 28 ms. In general, the current CARIBU EBIS operational parameters can provide charge breeding of any ions in the full mass range of periodic table with high efficiency, short breeding times, and sufficiently low charge-to-mass ratio, 1/6.3 for the heaviest masses, for further acceleration in ATLAS. In this study, we discuss the parameters of the EBIS and the charge breeding results in a pulsed injection mode with repetition rates up to 10 Hz.

  9. Fast and efficient charge breeding of the Californium rare isotope breeder upgrade electron beam ion source

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ostroumov, P. N.; Barcikowski, A.; Dickerson, C. A.; Perry, A.; Pikin, A. I.; Sharamentov, S. I.; Vondrasek, R. C.; Zinkann, G. P.

    2015-08-28

    The Electron Beam Ion Source (EBIS), developed to breed Californium Rare Isotope Breeder Upgrade (CARIBU) radioactive beams at Argonne Tandem Linac Accelerator System (ATLAS), is being tested off-line. A unique property of the EBIS is a combination of short breeding times, high repetition rates, and a large acceptance. Overall, we have implemented many innovative features during the design and construction of the CARIBU EBIS as compared to the existing EBIS breeders. The off-line charge breeding tests are being performed using a surface ionization source that produces singly charged cesium ions. The main goal of the off-line commissioning is to demonstratemore »stable operation of the EBIS at a 10 Hz repetition rate and a breeding efficiency into single charge state higher than 15%. These goals have been successfully achieved and exceeded. We have measured (20% ± 0.7%) breeding efficiency into the single charge state of 28+ cesium ions with the breeding time of 28 ms. In general, the current CARIBU EBIS operational parameters can provide charge breeding of any ions in the full mass range of periodic table with high efficiency, short breeding times, and sufficiently low charge-to-mass ratio, 1/6.3 for the heaviest masses, for further acceleration in ATLAS. In this study, we discuss the parameters of the EBIS and the charge breeding results in a pulsed injection mode with repetition rates up to 10 Hz.« less

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

    SciTech Connect (OSTI)

    Niklas, Martin; Abdollahi, Amir; Akselrod, Mark S.; Debus, Jürgen; Jäkel, Oliver; and others

    2013-12-01

    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.

  11. Mechanisms for covalent immobilization of horseradish peroxi-dase on ion beam treated polyethylene

    E-Print Network [OSTI]

    Kondyurin, Alexey V; Tilley, Jennifer M R; Nosworthy, Neil J; Bilek, Marcela M M; McKenzie, David R

    2011-01-01

    The mechanism that provides the observed strong binding of biomolecules to polymer sur-faces modified by ion beams is investigated. The surface of polyethylene (PE) was modified by plasma immersion ion implantation with nitrogen ions. Structure changes including car-bonization and oxidation were observed in the modified surface layer of PE by Raman spec-troscopy, FTIR ATR spectroscopy, atomic force microscopy, surface energy measurement and XPS spectroscopy. An observed high surface energy of the modified polyethylene was attributed to the presence of free radicals on the surface. The surface energy decay with stor-age time after PIII treatment was explained by a decay of the free radical concentration while the concentration of oxygen-containing groups increased with storage time. Horseradish per-oxidase was covalently attached onto the modified PE surface. The enzymatic activity of co-valently attached protein remained high. A mechanism based on the covalent attachment by the reaction of protein with free r...

  12. Transfer of polarized 3He ions in the AtR beam transfer line

    SciTech Connect (OSTI)

    Tsoupas N.; MacKay, W.W.; Meot, F.; Roser, T.; Trbojevic, D.

    2012-05-20

    In addition to collisions of electrons with various unpolarized ion species as well as polarized protons, the proposed electron-hadron collider (eRHIC) will facilitate the collisions of electrons with polarized {sup 3}He ions. The AGS is the last acceleration stage, before injection into one of the RHIC's collider ring for final acceleration. The AtR (AGS to RHIC) transfer line will be utilized to transport the polarized {sup 3}He ions from AGS into one of the RHIC's collider rings. Some of the peculiarities of the AtR line's layout (simultaneous horizontal and vertical bends) may degrade the matching of the stable spin direction of the AtR line with that of RHIC's. In this paper we discuss possible simple modifications of the AtR line to accomplish a perfect matching of the stable spin direction of the injected {sup 3}He beam with the stable spin direction at the injection point of RHIC.

  13. Transport of radioactive ion beams and related safety issues: The {sup 132}Sn{sup +} case study

    SciTech Connect (OSTI)

    Osswald, F. Bouquerel, E.; Boutin, D.; Dinkov, A.; Sellam, A.

    2014-12-15

    The transport of intense radioactive ion beam currents requires a careful design in order to limit the beam losses, the contamination and thus the dose rates. Some investigations based on numerical models and calculations have been performed in the framework of the SPIRAL 2 project to evaluate the performance of a low energy beam transport line located between the isotope separation on line (ISOL) production cell and the experiment areas. The paper presents the results of the transverse phase-space analysis, the beam losses assessment, the resulting contamination, and radioactivity levels. They show that reasonable beam transmission, emittance growth, and dose rates can be achieved considering the current standards.

  14. 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)

    2014-11-15

    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.

  15. Feasibility study of heavy ion beams and compound target materials for muon production

    E-Print Network [OSTI]

    Jaebum Son; Ju Hahn Lee; Gi Dong Kim; Yong Kyun Kim

    2015-07-15

    We have investigated the feasibility of using compound materials as target for muon production by virtue of simulations using a GEANT4 toolkit. A graphite and two thermostable compound materials, beryllium oxide (BeO) and boron carbide (B4C) were considered as muon production targets and their muon production rates for 600-MeV proton beam were calculated and compared. For thermal analysis, total heat deposited on the targets by the proton beams and the secondary particles was calculated with a MCNPX code, and then the temperature distribution of target was derived from the calculated heat by using an ANSYS code with consideration for heat transfer mechanisms, such as thermal conduction and thermal radiation. In addition, we have investigated whether the heavy ion beams can be utilized for muon production. For various beam species such as 3He2, 4He, 7Li, 10B and 12C, their muon production rates were calculated and compared with that obtained for a proton beam.

  16. Feasibility study of heavy ion beams and compound target materials for muon production

    E-Print Network [OSTI]

    Son, Jaebum; Kim, Gi Dong; Kim, Yong Kyun

    2015-01-01

    We have investigated the feasibility of using compound materials as target for muon production by virtue of simulations using a GEANT4 toolkit. A graphite and two thermostable compound materials, beryllium oxide (BeO) and boron carbide (B4C) were considered as muon production targets and their muon production rates for 600-MeV proton beam were calculated and compared. For thermal analysis, total heat deposited on the targets by the proton beams and the secondary particles was calculated with a MCNPX code, and then the temperature distribution of target was derived from the calculated heat by using an ANSYS code with consideration for heat transfer mechanisms, such as thermal conduction and thermal radiation. In addition, we have investigated whether the heavy ion beams can be utilized for muon production. For various beam species such as 3He2, 4He, 7Li, 10B and 12C, their muon production rates were calculated and compared with that obtained for a proton beam.

  17. 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)

    2014-02-07

    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.

  18. Comment on “Stationary self-focusing of Gaussian laser beam in relativistic thermal quantum plasma” [Phys. Plasmas 20, 072703 (2013)

    SciTech Connect (OSTI)

    Habibi, M.; Ghamari, F.

    2014-06-15

    Patil and Takale in their recent article [Phys. Plasmas 20, 072703 (2013)], by evaluating the quantum dielectric response in thermal quantum plasma, have modeled the relativistic self-focusing of Gaussian laser beam in a plasma. We have found that there are some important shortcomings and fundamental mistakes in Patil and Takale [Phys. Plasmas 20, 072703 (2013)] that we give a brief description about them and refer readers to important misconception about the use of the Fermi temperature in quantum plasmas, appearing in Patil and Takale [Phys. Plasmas 20, 072703 (2013)].

  19. Progress in beam focusing and compression for warm-dense matter experiments

    E-Print Network [OSTI]

    Gilson, Erik

    ) was effectively neutralized with RF and cathodic-arc plasma sources [3]. Th, USA c University of California, Berkeley, CA 94720, USA d Princeton Plasma Physics Laboratory-dependent focusing elements to correct considerable chromatic aberrations; and (4) plasma injection improvements

  20. Focused ion beam modification of atomic force microscopy tips for near-field scanning optical microscopy

    E-Print Network [OSTI]

    Krogmeier, Jeffrey R.; Dunn, Robert C.

    2001-12-01

    fabri- cation process and the need for expensive FIB instrumenta- tion, but these impediments may be minimized as the fabri- cation techniques are refined. Since these tips share many of the physical characteristics of AFM probes, they should be capable... fabri- cation process and the need for expensive FIB instrumenta- tion, but these impediments may be minimized as the fabri- cation techniques are refined. Since these tips share many of the physical characteristics of AFM probes, they should be capable...

  1. Low-temperature charge transport in Ga-acceptor nanowires implanted by focused-ion beams

    E-Print Network [OSTI]

    Robinson, SJ

    2008-01-01

    Low-Temperature Charge Transport in Ga-Acceptor Nanowiresare highly nonlinear at low temperatures, and a thresholdmetallic conductance at low temperatures could be achieved

  2. Focused ion beam specimen preparation for electron holography of electrically biased thin film solar cells

    E-Print Network [OSTI]

    Dunin-Borkowski, Rafal E.

    solar cells M. Duchamp1 , M. den Hertog2 , R. Imlau1 , C. B. Boothroyd1 , A. Kovács1 , A. H. Tavabi1, biased TEM specimen, thin film solar cell, FIB Thin films of hydrogenated Si (Si:H) can be used as active absorber layers in solar cells deposited on low cost substrates using plasma-enhanced chemical vapour

  3. Three-dimensional defect characterization : focused ion beam tomography applied to tin sulfide thin films

    E-Print Network [OSTI]

    Youssef, Amanda

    2014-01-01

    Porosity is postulated to be one of the reasons for the low efficiency of tin sulfide-based devices. This work is a preliminary investigation of the effects of two film growth parameters deposition rate and substrate ...

  4. Deposition of metallic gallium on re-crystallized ceramic material during focused ion beam milling

    SciTech Connect (OSTI)

    Muñoz-Tabares, J.A.; Reyes-Gasga, J.

    2013-12-15

    We report a new kind of artifact observed in the preparation of a TEM sample of zirconia by FIB, which consists in the deposition of metallic gallium nano-dots on the TEM sample surface. High resolution TEM images showed a microstructure of fine equiaxed grains of ? 5 nm, with some of them possessing two particular characteristics: high contrast and well-defined fast Fourier transform. These grains could not be identified as any phase of zirconia but it was possible to identify them as gallium crystals in the zone axis [110]. Based on HRTEM simulations, the possible orientations between zirconia substrate and deposited gallium are discussed in terms of lattice mismatch and oxygen affinity. - Highlights: • We show a new type of artifact induced during preparation of TEM samples by FIB. • Deposition of Ga occurs due to its high affinity for oxygen. • Materials with small grain size (? 5 nm) could promote Ga deposition. • Small grain size permits the elastic accommodation of deposited Ga.

  5. Customized atomic force microscopy probe by focused-ion-beam-assisted tip

    Office of Scientific and Technical Information (OSTI)

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnect Collidertransfer (Journal Article) | SciTech Connect Customized

  6. Ion species control in high flux deuterium plasma beams produced by a linear plasma generator

    SciTech Connect (OSTI)

    Luo, G.-N.; Shu, W.M.; Nakamura, H.; O'Hira, S.; Nishi, M.

    2004-11-01

    The ion species ratios in low energy high flux deuterium plasma beams formed in a linear plasma generator were measured by a quadrupole mass spectrometer. And the species control in the plasma generator was evaluated by changing the operational parameters like neutral pressure, arc current, and axial magnetic confinement to the plasma column. The measurements reveal that the lower pressures prefer to form more D{sup +} ions, and the medium magnetic confinement at the higher pressures results in production of more D{sub 2}{sup +}, while the stronger confinement and/or larger arc current are helpful to D{sub 2}{sup +} conversion into D{sub 3}{sup +}. Therefore, the ion species can be controlled by adjusting the operational parameters of the plasma generator. With suitable adjustment, we can achieve plasma beams highly enriched with a single species of D{sup +}, D{sub 2}{sup +}, or D{sub 3}{sup +}, to a ratio over 80%. It has been found that the axial magnetic configuration played a significant role in the formation of D{sub 3}{sup +} within the experimental pressure range.

  7. Two-dimensional PIC simulations of ion-beam instabilities in Supernova-driven plasma flows

    E-Print Network [OSTI]

    M. E. Dieckmann; A. Meli; P. K. Shukla; L. O. C. Drury; A. Mastichiadis

    2008-04-16

    Supernova remnant (SNR) blast shells can reach the flow speed $v_s = 0.1 c$ and shocks form at its front. Instabilities driven by shock-reflected ion beams heat the plasma in the foreshock, which may inject particles into diffusive acceleration. The ion beams can have the speed $v_b \\approx v_s$. For $v_b \\ll v_s$ the Buneman or upper-hybrid instabilities dominate, while for $v_b \\gg v_s$ the filamentation and mixed modes grow faster. Here the relevant waves for $v_b \\approx v_s$ are examined and how they interact nonlinearly with the particles. The collision of two plasma clouds at the speed $v_s$ is modelled with particle-in-cell (PIC) simulations, which convect with them magnetic fields oriented perpendicular to their flow velocity vector. One simulation models equally dense clouds and the other one uses a density ratio of 2. Both simulations show upper-hybrid waves that are planar over large spatial intervals and that accelerate electrons to $\\sim$ 10 keV. The symmetric collision yields only short oscillatory wave pulses, while the asymmetric collision also produces large-scale electric fields, probably through a magnetic pressure gradient. The large-scale fields destroy the electron phase space holes and they accelerate the ions, which facilitates the formation of a precursor shock.

  8. Development and Application of an Electrospray Ionization Ion Mobility-mass Spectrometer Using an RF Ion Funnel and Periodic-focusing Ion Guide 

    E-Print Network [OSTI]

    Jeon, Junho

    2013-10-16

    A novel ion mobility-mass spectrometer was designed and built in order to achieve high transmission and high resolution for observing desolvated ion conformations of chemical and biological molecules in the gas phase. The instrument incorporates a...

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

    SciTech Connect (OSTI)

    Guo, Fanqing

    2004-12-09

    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.

  10. Nanofabrication of sharp diamond tips by e-beam lithography and inductively coupled plasma reactive ion etching.

    SciTech Connect (OSTI)

    Moldovan, N.; Divan, R.; Zeng, H.; Carlisle, J. A.; Advanced Diamond Tech.

    2009-12-07

    Ultrasharp diamond tips make excellent atomic force microscopy probes, field emitters, and abrasive articles due to diamond's outstanding physical properties, i.e., hardness, low friction coefficient, low work function, and toughness. Sharp diamond tips are currently fabricated as individual tips or arrays by three principal methods: (1) focused ion beam milling and gluing onto a cantilever of individual diamond tips, (2) coating silicon tips with diamond films, or (3) molding diamond into grooves etched in a sacrificial substrate, bonding the sacrificial substrate to another substrate or electrodepositing of a handling chip, followed by dissolution of the sacrificial substrate. The first method is tedious and serial in nature but does produce very sharp tips, the second method results in tips whose radius is limited by the thickness of the diamond coating, while the third method involves a costly bonding and release process and difficulties in thoroughly filling the high aspect ratio apex of molding grooves with diamond at the nanoscale. To overcome the difficulties with these existing methods, this article reports on the feasibility of the fabrication of sharp diamond tips by direct etching of ultrananocrystalline diamond (UNCD{reg_sign}) as a starting and structural material. The UNCD is reactive ion etched using a cap-precursor-mask scheme. An optimized etching recipe demonstrates the formation of ultrasharp diamond tips ({approx} 10 nm tip radius) with etch rates of 650 nm/min.

  11. Electrostatically focused addressable field emission array chips (AFEA's) for high-speed massively parallel maskless digital E-beam direct write lithography and scanning electron microscopy

    DOE Patents [OSTI]

    Thomas, Clarence E. (Knoxville, TN); Baylor, Larry R. (Farragut, TN); Voelkl, Edgar (Oak Ridge, TN); Simpson, Michael L. (Knoxville, TN); Paulus, Michael J. (Knoxville, TN); Lowndes, Douglas H. (Knoxville, TN); Whealton, John H. (Oak Ridge, TN); Whitson, John C. (Clinton, TN); Wilgen, John B. (Oak Ridge, TN)

    2002-12-24

    Systems and methods are described for addressable field emission array (AFEA) chips. A method of operating an addressable field-emission array, includes: generating a plurality of electron beams from a pluralitly of emitters that compose the addressable field-emission array; and focusing at least one of the plurality of electron beams with an on-chip electrostatic focusing stack. The systems and methods provide advantages including the avoidance of space-charge blow-up.

  12. Analysis methods of safe Coulomb-excitation experiments with radioactive ion beams using the gosia code

    E-Print Network [OSTI]

    Zieli?ska, M; Wrzosek-Lipska, K; Clément, E; Grahn, T; Kesteloot, N; Napiorkowski, P; Pakarinen, J; Van Duppen, P; Warr, N

    2015-01-01

    With the recent advances in radioactive ion beam technology, Coulomb excitation at safe energies becomes an important experimental tool in nuclear structure physics. The usefulness of the technique to extract key information on the electromagnetic properties of nuclei has been demonstrated since the 1960's with stable beam and target combinations. New challenges present themselves when studying exotic nuclei with this technique, including dealing with low statistics or number of data points, absolute and relative normalisation of the measured cross sections and a lack of complimentary experimental data, such as excited-state lifetimes and branching ratios. This paper addresses some of these common issues and presents analysis techniques to extract transition strengths and quadrupole moments utilising the least-squares fit code, {\\rmfamily \\textsc{gosia}}.

  13. Analysis methods of safe Coulomb-excitation experiments with radioactive ion beams using the gosia code

    E-Print Network [OSTI]

    M. Zieli?ska; L. P. Gaffney; K. Wrzosek-Lipska; E. Clément; T. Grahn; N. Kesteloot; P. Napiorkowski; J. Pakarinen; P. Van Duppen; N. Warr

    2015-06-16

    With the recent advances in radioactive ion beam technology, Coulomb excitation at safe energies becomes an important experimental tool in nuclear structure physics. The usefulness of the technique to extract key information on the electromagnetic properties of nuclei has been demonstrated since the 1960's with stable beam and target combinations. New challenges present themselves when studying exotic nuclei with this technique, including dealing with low statistics or number of data points, absolute and relative normalisation of the measured cross sections and a lack of complimentary experimental data, such as excited-state lifetimes and branching ratios. This paper addresses some of these common issues and presents analysis techniques to extract transition strengths and quadrupole moments utilising the least-squares fit code, {\\rmfamily \\textsc{gosia}}.

  14. 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)

    2014-11-15

    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.

  15. Ion beam measurement of deuterium in palladium and calculation of hydrogen isotope separation factors

    SciTech Connect (OSTI)

    Gullinger, T.R.; Kelly, M.J.; Knapp, J.A.; Walsh, D.S.; Doyle, B.L. )

    1991-08-01

    In this paper, the authors demonstrate a new technique for measuring hydrogen isotope separation factors in hydrogen-absorbing metals. Using external ion beam nuclear reaction analysis of metal electrodes in an operating electrochemical cell, the authors monitor in situ the deuterium content of the electrode. changing the deuterium/hydrogen ratio in the electrolyte changes the observed deuterium content of the metal electrode, and, assuming identical ultimate total metal loading for deuterium, hydrogen, and any mixture of deuterium and hydrogen, a simple calculation yields the separation factor.

  16. Ion Beams - Radiation Effects Facility / Cyclotron Institute / Texas A&M

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation CurrentHenryInhibitingInteractivePGAS andUniversity Ion Beams Available

  17. 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)

    2014-11-07

    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.

  18. In-situ Study of Nanostructure and Electrical Resistance of Nanocluster Films Irradiated with Ion Beams

    SciTech Connect (OSTI)

    Jiang, Weilin; Sundararajan, Jennifer A.; Varga, Tamas; Bowden, Mark E.; Qiang, You; McCloy, John S.; Henager, Charles H.; Montgomery, Robert O.

    2014-08-11

    An in-situ study is reported on the structural evolution in nanocluster films under He+ ion irradiation using an advanced helium ion microscope. The films consist of loosely interconnected nanoclusters of magnetite or iron-magnetite (Fe-Fe3O4) core-shells. The nanostructure is observed to undergo dramatic changes under ion-beam irradiation, featuring grain growth, phase transition, particle aggregation, and formation of nanowire-like network and nano-pores. Studies based on ion irradiation, thermal annealing and election irradiation have indicated that the major structural evolution is activated by elastic nuclear collisions, while both electronic and thermal processes can play a significant role once the evolution starts. The electrical resistance of the Fe-Fe3O4 films measured in situ exhibits a super-exponential decay with dose. The behavior suggests that the nanocluster films possess an intrinsic merit for development of an advanced online monitor for neutron radiation with both high detection sensitivity and long-term applicability, which can enhance safety measures in many nuclear operations.

  19. 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)

    1985-01-01

    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.

  20. Drift compression and final focus systems for heavy ion inertial fusion

    E-Print Network [OSTI]

    de Hoon, M.J.L.

    2001-01-01

    cheapest source of energy; an a?ordable cost of electricitycheapest source of energy in the near future, partic- ularly heavy ion fusion is expected to be able to provide electricity

  1. Characterization of Ion Species Mix of the Textor Diagnostic Hydrogen Beam Injector with an RF and Arc-discharge Plasma Box

    E-Print Network [OSTI]

    Ivanov, A A; Kreter, A; Maximov, V V; Podmonogin, A A; Schweer, B; Shikhoutsev, I V; Stupishin, N V; Uhlemann, R; Usoltsev, D V

    2002-01-01

    Characterization of Ion Species Mix of the Textor Diagnostic Hydrogen Beam Injector with an RF and Arc-discharge Plasma Box

  2. Raster-scanning serial protein crystallography using micro- and nano-focused synchrotron beams

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Coquelle, Nicolas; Brewster, Aaron S.; Kapp, Ulrike; Shilova, Anastasya; Weinhausen, Britta; Burghammer, Manfred; Colletier, Jacques -Philippe

    2015-04-25

    High-resolution structural information was obtained from lysozyme microcrystals (20 µm in the largest dimension) using raster-scanning serial protein crystallography on micro- and nano-focused beamlines at the ESRF. Data were collected at room temperature (RT) from crystals sandwiched between two silicon nitride wafers, thereby preventing their drying, while limiting background scattering and sample consumption. In order to identify crystal hits, new multi-processing and GUI-driven Python-based pre-analysis software was developed, named NanoPeakCell, that was able to read data from a variety of crystallographic image formats. Further data processing was carried out using CrystFEL, and the resultant structures were refined to 1.7 Åmore »resolution. The data demonstrate the feasibility of RT raster-scanning serial micro- and nano-protein crystallography at synchrotrons and validate it as an alternative approach for the collection of high-resolution structural data from micro-sized crystals. Advantages of the proposed approach are its thriftiness, its handling-free nature, the reduced amount of sample required, the adjustable hit rate, the high indexing rate and the minimization of background scattering.« less

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

    SciTech Connect (OSTI)

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

    1990-10-01

    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.

  4. Ion beam-induced amorphous-to-tetragonal phase transformation and grain growth of nanocrystalline zirconia

    SciTech Connect (OSTI)

    Lian, Jie; Zhang, Jiaming; Namavar, Fereydoon; Zhang, Yanwen; Lu, Fengyuan; Haider, Hani; Garvin, Kevin; Weber, William J.; Ewing, Rodney C.

    2009-05-26

    Nanocrystalline zirconia has recently attracted extensive research interest due to its unique mechanical, thermal and electrical properties as compared to bulk zirconia counterparts, and it is of particular importance to control the phase stability of different polymorphs (amorphous, cubic, tetragonal and monoclinic phases) at different size regimes. In this paper, we performed ion beam bombardments on bilayers (amorphous and cubic) of pure nano-zirconia using 1 MeV Kr2+ irradiation. Transmission electron microscopy (TEM) analysis reveals that amorphous zirconia transforms to a tetragonal structure under irradiation at room temperature, suggesting that the tetragonal phase is more energetically favorable under these conditions. The final grain size of the tetragonal zirconia can be controlled by irradiation conditions. The irradiation-induced nanograins of tetragonal ZrO2 are stable at ambient conditions and maintain their physical integrity over a long period of time after irradiation. These results demonstrated that ion-beam modification methods provide the means to control the phase stability and structure of zirconia polymorphs.

  5. Heavy ion beam probe operation in time varying equilibria of improved confinement reversed field pinch discharges

    SciTech Connect (OSTI)

    Demers, D. R.; Chen, X.; Schoch, P. M. [Rensselaer Polytechnic Institute, Troy, New York 12180 (United States); Fimognari, P. J. [University of Wisconsin, Madison, Wisconsin 53706 (United States)

    2010-10-15

    Operation of a heavy ion beam probe (HIBP) on a reversed field pinch is unique from other toroidal applications because the magnetic field is more temporal and largely produced by plasma current. Improved confinement, produced through the transient application of a poloidal electric field which leads to a reduction of dynamo activity, exhibits gradual changes in equilibrium plasma quantities. A consequence of this is sweeping of the HIBP trajectories by the dynamic magnetic field, resulting in motion of the sample volume. In addition, the plasma potential evolves with the magnetic equilibrium. Measurement of the potential as a function of time is thus a combination of temporal changes of the equilibrium and motion of the sample volume. A frequent additional complication is a nonideal balance of ion current on the detectors resulting from changes in the beam trajectory (magnetic field) and energy (plasma potential). This necessitates use of data selection criteria. Nevertheless, the HIBP on the Madison Symmetric Torus has acquired measurements as a function of time throughout improved confinement. A technique developed to infer the potential in the improved confinement reversed field pinch from HIBP data in light of the time varying plasma equilibrium will be discussed.

  6. Magnetic domain structures of focused ion beam-patterned cobalt films using scanning ion microscopy with polarization analysis

    E-Print Network [OSTI]

    Rau, Carl

    in the areas of ultrahigh density magnetic recording, MRAM design, and miniaturized magnetic sensor arrays, it is found that rectangular Co bars of sizes between 10­30 m exhibit S type, whereas circular shaped magnetic elements show C type micromagnetic magnetization patterns. It is shown that SIMPA provides a simple way

  7. Efficient quasi-monoenergetic ion beams up to 18 MeV/nucleon via self-generated plasma fields in relativistic laser plasmas

    E-Print Network [OSTI]

    Palaniyappan, Sasi; Gautier, Donald C; Hamilton, Christopher E; Santiago, Miguel A; Kreuzer, Christian; Shah, Rahul C; Fernandez, Juan C

    2015-01-01

    Table-top laser-plasma ion accelerators seldom achieve narrow energy spreads, and never without serious compromises in efficiency, particle yield, etc. Using massive computer simulations, we identify a self-organizing scheme that exploits persisting self-generated plasma electric (~TV/m) and magnetic (~10${}^{4}$ Tesla) fields to reduce the ion energy spread after the laser exits the plasma - separating the ion acceleration from the energy spread reduction. Consistent with the scheme, we experimentally demonstrate aluminum and carbon ion beams with narrow spectral peaks at energies up to 310 MeV (11.5 MeV/nucleon) and 220 MeV (18.3 MeV/nucleon), respectively, with high conversion efficiency (~5%, i.e., 4J out of 80J laser). This is achieved with 0.12 PW high-contrast Gaussian laser pulses irradiating planar foils with optimal thicknesses of up to 250 nm that scale with laser intensity. When increasing the focused laser intensity fourfold (by reducing the focusing optic f/number twofold), the spectral-peak ene...

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

    E-Print Network [OSTI]

    De Melo Mendonca, T M

    2014-01-01

    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...

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

    E-Print Network [OSTI]

    Tiefenback, M.G.

    2011-01-01

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

  10. Effect of the plasma instability on the beam intensity from RIKEN 18 GHz electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Higurashi, Y.; Nakagawa, T.; Kidera, M.; Aihara, T.; Kobayashi, K.; Kase, M.; Goto, A.; Yano, Y. [RIKEN, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan); SAS Ltd., Kita-shinagawa 5-9-11, Shinjuku-ku, Tokyo (Japan); RIKEN, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan)

    2006-03-15

    We measured the beam oscillation of RIKEN 18 GHz electron cyclotron resonance ion source for various conditions. In this experiment, the frequency of the beam oscillation increases with increasing the gas pressure and decreases with increasing rf power. The oscillation frequency is strongly dependent on the negative voltage of biased disk, i.e., the frequency increases with increasing the negative voltage. We observed that the frequency is strongly dependent on the mass of ionized gas.

  11. Focused Gaussian Beams for Seismic Imaging Robert L. Nowack*; Dept. of Earth and Atmos. Sci., Purdue University

    E-Print Network [OSTI]

    Nowack, Robert L.

    at a specific depth is that fewer beams are required for that image depth. Recent true amplitude migration to occur at the depth of a specific target structure. This minimizes the number of beams required to form an image at the target depth. The beam fronts at the beam-waists are also planar leading to more stable

  12. An estimate of the error caused by the elongation of the wavelength in a focused beam in free-space electromagnetic parameters measurement

    SciTech Connect (OSTI)

    Zhang, Yunpeng; Li, En Guo, Gaofeng; Xu, Jiadi; Wang, Chao

    2014-09-15

    A pair of spot-focusing horn lens antenna is the key component in a free-space measurement system. The electromagnetic constitutive parameters of a planar sample are determined using transmitted and reflected electromagnetic beams. These parameters are obtained from the measured scattering parameters by the microwave network analyzer, thickness of the sample, and wavelength of a focused beam on the sample. Free-space techniques introduced by most papers consider the focused wavelength as the free-space wavelength. But in fact, the incident wave projected by a lens into the sample approximates a Gaussian beam, thus, there has an elongation of the wavelength in the focused beam and this elongation should be taken into consideration in dielectric and magnetic measurement. In this paper, elongation of the wavelength has been analyzed and measured. Measurement results show that the focused wavelength in the vicinity of the focus has an elongation of 1%–5% relative to the free-space wavelength. Elongation's influence on the measurement result of the permittivity and permeability has been investigated. Numerical analyses show that the elongation of the focused wavelength can cause the increase of the measured value of the permeability relative to traditionally measured value, but for the permittivity, it is affected by several parameters and may increase or decrease relative to traditionally measured value.

  13. 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)

    2012-02-15

    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.

  14. Characterization of electrospray ion-beam-deposited CdSe/ZnS quantum dot thin films from a colloidal solution

    SciTech Connect (OSTI)

    Tani, Yuki; Kobayashi, Satoshi; Kawazoe, Hiroshi

    2008-07-15

    Colloidal semiconductor quantum dot (QD) nanocrystals can be deposited in the form of inorganic thin films using the ion beam direct deposition method. To simultaneously preserve the nanocrystal configuration and remove the organics derived from the ligand and solvent, the authors used an electrospray technique and an ion beam technique. These techniques provided a soft-ionization process to obtain nanocrystalline ions and a collision process to attain a nonequilibrium state of the deposits, respectively. Because of the nature of the soft-ionization process, the electrospray phenomenon resulted in various forms of QD ions that depended on the preparation of the colloidal solution source and spraying conditions. The authors concentrated on finding operational conditions of the system that deposited thin films with reduced organics concentrations by examining the correlation between fast Fourier transform infrared absorption spectroscopy and photoluminescence intensity. The morphology of the deposited films was observed using an atomic force microscope.

  15. Structural Modification of Single Wall and Multiwalled Carbon Nanotubes under Carbon, Nickel and Gold Ion Beam Irradiation

    SciTech Connect (OSTI)

    Jeet, Kiran; Jindal, V. K.; Dharamvir, Keya; Bharadwaj, L. M.

    2011-12-12

    Thin film samples of carbon nanotubes were irradiated with ion beam of carbon, nickel and gold. The irradiation results were characterized using Raman Spectroscopy. Modifications of the disorder mode (D mode) and the tangential mode (G mode) under different irradiation fluences were studied in detail. Raman results of carbon ion beam indicate the interesting phenomenon of ordering of the system under irradiation. Under the effect of nickel and gold ion irradiation, the structural evolution of CNTs occurs in three different stages. At lower fluences the process of healing occurs; at intermediate fluences damages on the surface of CNTs occurs and finally at very high fluences of the order of 1x10{sup 14} ions/cm{sup 2} the system gets amorphised.

  16. A high-current electron gun for the electron beam ion trap at the National Superconducting Cyclotron Laboratory

    SciTech Connect (OSTI)

    Schwarz, S. Baumann, T. M.; Kittimanapun, K.; Lapierre, A.; Snyder, A.

    2014-02-15

    The Electron Beam Ion Trap (EBIT) in NSCL’s reaccelerator ReA uses continuous ion injection and accumulation. In order to maximize capture efficiency and minimize breeding time into high charge states, the EBIT requires a high-current/high current-density electron beam. A new electron gun insert based on a concave Ba-dispenser cathode has been designed and built to increase the current transmitted through the EBIT’s superconducting magnet. With the new insert, stable EBIT operating conditions with 0.8 A of electron beam have been established. The design of the electron gun is presented together with calculated and measured perveance data. In order to assess the experimental compression of the electron beam, a pinhole CCD camera has been set up to measure the electron beam radius. The camera observes X-rays emitted from highly charged ions, excited by the electron beam. Initial tests with this camera setup will be presented. They indicate that a current density of 640 A/cm{sup 2} has been reached when the EBIT magnet was operated at 4 T.

  17. Increasing the upper-limit intensity and temperature range for thermal self-focusing of a laser beam by using plasma density ramp-up

    SciTech Connect (OSTI)

    Bokaei, B.; Niknam, A. R.

    2014-03-15

    This work is devoted to improving relativistic and ponderomotive thermal self-focusing of the intense laser beam in an underdense plasma. It is shown that the ponderomotive nonlinearity induces a saturation mechanism for thermal self-focusing. Therefore, in addition to the well-known lower-limit critical intensity, there is an upper-limit intensity for thermal self-focusing above which the laser beam starts to experience ponderomotive defocusing. It is indicated that the upper-limit intensity value is dependent on plasma and laser parameters such as the plasma electron temperature, plasma density, and laser spot size. Furthermore, the effect of the upward plasma density ramp profile on the thermal self-focusing is studied. Results show that by using the plasma density ramp-up, the upper-limit intensity increases and the self-focusing temperature range expands.

  18. 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

    2011-03-20

    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.

  19. Operation of a multiple cell array detector in plasma experiments with a heavy ion beam diagnostic

    SciTech Connect (OSTI)

    Goncalves, B.; Malaquias, A.; Nedzelskiy, I. S.; Pereira, L.; Silva, C.; Varandas, C.A.F.; Cabral, J.A.C.; Khrebtov, S.M.; Dreval, N.B.; Krupnik, L.I.; Hidalgo, C.; Depablos, J.

    2004-10-01

    A multiple cell array detector (MCAD) has been developed to investigate the spatial structure of plasma turbulence in fusion plasmas. This system is expected to provide simultaneous measurements of edge and core density fluctuations with both temporal and spatial resolution, extending the range and number of the sample volumes simultaneously recorded by a heavy ion beam diagnostic (HIBD). Since the detector (usually located close to the vessel wall of a plasma device) operates in a strong plasma radiation environment, the effective shielding of the detector presents a special problem. This article describes and compares the MCAD operation conditions on ISTTOK tokamak and TJ-II stellarator. Experimental results of the detector performance are presented together with the first measurements of n{sub e}{sigma}{sub eff} in the TJ-II plasmas.

  20. 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.

    2011-10-15

    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.

  1. 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

    2012-03-05

    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.

  2. Superconductivity and metallic behavior in Pb{sub x}C{sub y}O{sub ?} structures prepared by focused electron beam induced deposition

    SciTech Connect (OSTI)

    Winhold, M., E-mail: winhold@Physik.uni-frankfurt.de; Weirich, P. M.; Schwalb, C. H.; Huth, M. [Physikalisches Institut, Goethe-University, 60438 Frankfurt am Main (Germany)

    2014-10-20

    Focused electron beam induced deposition as a direct-write approach possesses great potential to meet the demands for superconducting nanostructure fabrication especially regarding its 3D patterning capabilities combined with the high resolution in the nanometer regime. So far, however, it was not possible to fabricate superconducting structures with this technique. In this work, we present a lead-based superconductor prepared by focused electron beam induced deposition by dissociation of the precursor tetraethyllead. The as-grown structures exhibit metallic behavior and a minimum resistivity in the normal state of ??=?16???cm at T?=?9?K followed by a superconducting transition at T{sub c}?=?7.2?K.

  3. Long plasma source for heavy ion beam charge neutralization Philip C. Efthimion a,, Erik P. Gilson a

    E-Print Network [OSTI]

    Gilson, Erik

    ]. In this longitudinal compression experiment, plasma was transported from a cathodic arc source to a meter distanceLong plasma source for heavy ion beam charge neutralization Philip C. Efthimion a,Ã, Erik P. Gilson a Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543, USA b Lawrence Berkeley National

  4. Generation of high charge state metal ion beams by electron cyclotron resonance heating of vacuum arc plasma in cusp trap

    SciTech Connect (OSTI)

    Nikolaev, A. G.; Savkin, K. P.; Oks, E. M.; Vizir, A. V.; Yushkov, G. Yu.; Vodopyanov, A. V.; Izotov, I. V.; Mansfeld, D. A.

    2012-02-15

    A method for generating high charge state heavy metal ion beams based on high power microwave heating of vacuum arc plasma confined in a magnetic trap under electron cyclotron resonance conditions has been developed. A feature of the work described here is the use of a cusp magnetic field with inherent ''minimum-B'' structure as the confinement geometry, as opposed to a simple mirror device as we have reported on previously. The cusp configuration has been successfully used for microwave heating of gas discharge plasma and extraction from the plasma of highly charged, high current, gaseous ion beams. Now we use the trap for heavy metal ion beam generation. Two different approaches were used for injecting the vacuum arc metal plasma into the trap - axial injection from a miniature arc source located on-axis near the microwave window, and radial injection from sources mounted radially at the midplane of the trap. Here, we describe preliminary results of heating vacuum arc plasma in a cusp magnetic trap by pulsed (400 {mu}s) high power (up to 100 kW) microwave radiation at 37.5 GHz for the generation of highly charged heavy metal ion beams.

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

    E-Print Network [OSTI]

    . The applications using this unique technology in low power consumption displays, fast switching color displays easily achieved because of the linear design of the ion beam sputtering source, which is a big challenge potentials for production of fast switching electro optical devices for display and other application. Basic

  6. Measurement of a magnetic-dipole transition probability in Xe32+ using an electron-beam ion trap 

    E-Print Network [OSTI]

    Serpa, F. G.; Morgan, C. A.; Meyer, E. S.; Gillaspy, J. D.; Trabert, E.; Church, David A.; Takacs, E.

    1997-01-01

    The transition probability for the 3d(4) D-5(2) <-- D-5(3) magnetic-dipole transition in Ti-like Xe (Xe32+) has been measured using an electron-beam ion trap. The unusually weak dependence of the transition energy on nuclear ...

  7. 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)

    2014-02-15

    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.

  8. Grating spectrometer system for beam emission spectroscopy diagnostics using high-energy negative-ion-based neutral beam injection on LHD

    SciTech Connect (OSTI)

    Kado, S. [School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Oishi, T. [Graduate School/School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Yoshinuma, M.; Ida, K. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292 (Japan)

    2010-10-15

    A beam emission spectroscopy (BES) system was developed for density gradient and fluctuation diagnostics in the Large Helical Device (LHD). In order to cover the large Doppler shift of the H{alpha} beam emission because of the high-energy negative-ion-based neutral beam atom (acceleration voltage V{sub acc}=90-170 kV) and the large motional Stark splitting due to the large vxB field (magnetic field B=3.0 T), a grating spectrometer was used instead of a conventional interference filter system. The reciprocal linear dispersion is about 2 nm/mm, which is sufficient to cover the motional Stark effect spectra using an optical fiber with a diameter of 1 mm.

  9. Demonstration of electronic pattern switching and 10x pattern demagnification in a maskless micro-ion beam reduction lithography system

    SciTech Connect (OSTI)

    Ngo, V.V.; Akker, B.; Leung, K.N.; Noh, I.; Scott, K.L.; Wilde, S.

    2002-05-31

    A proof-of-principle ion projection lithography (IPL) system called Maskless Micro-ion beam Reduction Lithography (MMRL) has been developed and tested at the Lawrence Berkeley National Laboratory (LBNL) for future integrated circuits (ICs) manufacturing and thin film media patterning [1]. This MMRL system is aimed at completely eliminating the first stage of the conventional IPL system [2] that contains the complicated beam optics design in front of the stencil mask and the mask itself. It consists of a multicusp RF plasma generator, a multi-beamlet pattern generator, and an all-electrostatic ion optical column. Results from ion beam exposures on PMMA and Shipley UVII-HS resists using 75 keV H+ are presented in this paper. Proof-of-principle electronic pattern switching together with 10x reduction ion optics (using a pattern generator made of nine 50-{micro}m switchable apertures) has been performed and is reported in this paper. In addition, the fabrication of a micro-fabricated pattern generator [3] on an SOI membrane is also presented.

  10. 326 IEEE JOURNAL OF QUANTUMELECTRONICS, VOL. QE-18, NO. 3, MARCH 1982 CW Iodine Ion Laser Excited by an Electron Beam

    E-Print Network [OSTI]

    Rocca, Jorge J.

    by an Electron Beam Abstract-CW laser oscillation has been obtained on the 5760.7 and 6127.5 A transitions of a dc electron beam created plasma as a new active medium for CW ion lasers. We report in this paper the generation of CW laser os- cillation in a He-12gas mixture using electron beam pumping. CW laser radiation

  11. 'Beam-emission spectroscopy' diagnostics also measure edge fast-ion light This article has been downloaded from IOPscience. Please scroll down to see the full text article.

    E-Print Network [OSTI]

    Heidbrink, William W.

    'Beam-emission spectroscopy' diagnostics also measure edge fast-ion light This article has been. Fusion 53 (2011) 085007 (19pp) doi:10.1088/0741-3335/53/8/085007 `Beam-emission spectroscopy' diagnostics June 2011 Online at stacks.iop.org/PPCF/53/085007 Abstract Beam-emission spectroscopy (BES) diagnostics

  12. Investigation of the mechanism of impurity assisted nanoripple formation on Si induced by low energy ion beam erosion

    SciTech Connect (OSTI)

    Koyiloth Vayalil, Sarathlal; Gupta, Ajay; Roth, Stephan V.; Ganesan, V.

    2015-01-14

    A detailed mechanism of the nanoripple pattern formation on Si substrates generated by the simultaneous incorporation of pure Fe impurities at low energy (1?keV) ion beam erosion has been studied. To understand and clarify the mechanism of the pattern formation, a comparative analysis of the samples prepared for various ion fluence values using two complimentary methods for nanostructure analysis, atomic force microscopy, and grazing incidence small angle x-ray scattering has been done. We observed that phase separation of the metal silicide formed during the erosion does not precede the ripple formation. It rather concurrently develops along with the ripple structure. Our work is able to differentiate among various models existing in the literature and provides an insight into the mechanism of pattern formation under ion beam erosion with impurity incorporation.

  13. Laboratory-based micro-X-ray fluorescence setup using a von Hamos crystal spectrometer and a focused beam X-ray tube

    SciTech Connect (OSTI)

    Kayser, Y.; B?achucki, W.; Dousse, J.-Cl.; Hoszowska, J.; Neff, M.; Romano, V.

    2014-04-15

    The high-resolution von Hamos bent crystal spectrometer of the University of Fribourg was upgraded with a focused X-ray beam source with the aim of performing micro-sized X-ray fluorescence (XRF) measurements in the laboratory. The focused X-ray beam source integrates a collimating optics mounted on a low-power micro-spot X-ray tube and a focusing polycapillary half-lens placed in front of the sample. The performances of the setup were probed in terms of spatial and energy resolution. In particular, the fluorescence intensity and energy resolution of the von Hamos spectrometer equipped with the novel micro-focused X-ray source and a standard high-power water-cooled X-ray tube were compared. The XRF analysis capability of the new setup was assessed by measuring the dopant distribution within the core of Er-doped SiO{sub 2} optical fibers.

  14. Response to “Comment on ‘Stationary self-focusing of Gaussian laser beam in relativistic thermal quantum plasma’” [Phys. Plasmas 21, 064701 (2014)

    SciTech Connect (OSTI)

    Patil, S. D.; Takale, M. V.

    2014-06-15

    Habibi and Ghamari have presented a Comment on our paper [Phys. Plasmas 20, 072703 (2013)] by examining quantum dielectric response in thermal quantum plasma. They have modeled the relativistic self-focusing of Gaussian laser beam in cold and warm quantum plasmas and reported that self-focusing length does not change in both situations. In this response, we have reached the following important conclusions about the comment itself.

  15. ACCELERATION OF LOW-ENERGY IONS AT PARALLEL SHOCKS WITH A FOCUSED TRANSPORT MODEL

    SciTech Connect (OSTI)

    Zuo, Pingbing; Zhang, Ming; Rassoul, Hamid K.

    2013-04-10

    We present a test particle simulation on the injection and acceleration of low-energy suprathermal particles by parallel shocks with a focused transport model. The focused transport equation contains all necessary physics of shock acceleration, but avoids the limitation of diffusive shock acceleration (DSA) that requires a small pitch angle anisotropy. This simulation verifies that the particles with speeds of a fraction of to a few times the shock speed can indeed be directly injected and accelerated into the DSA regime by parallel shocks. At higher energies starting from a few times the shock speed, the energy spectrum of accelerated particles is a power law with the same spectral index as the solution of standard DSA theory, although the particles are highly anisotropic in the upstream region. The intensity, however, is different from that predicted by DSA theory, indicating a different level of injection efficiency. It is found that the shock strength, the injection speed, and the intensity of an electric cross-shock potential (CSP) jump can affect the injection efficiency of the low-energy particles. A stronger shock has a higher injection efficiency. In addition, if the speed of injected particles is above a few times the shock speed, the produced power-law spectrum is consistent with the prediction of standard DSA theory in both its intensity and spectrum index with an injection efficiency of 1. CSP can increase the injection efficiency through direct particle reflection back upstream, but it has little effect on the energetic particle acceleration once the speed of injected particles is beyond a few times the shock speed. This test particle simulation proves that the focused transport theory is an extension of DSA theory with the capability of predicting the efficiency of particle injection.

  16. Relativistic self-focusing of ultra-high intensity X-ray laser beams in warm quantum plasma with upward density profile

    SciTech Connect (OSTI)

    Habibi, M.; Ghamari, F.

    2014-05-15

    The results of a numerical study of high-intensity X-ray laser beam interaction with warm quantum plasma (WQP) are presented. By means of an upward ramp density profile combined with quantum factors specially the Fermi velocity, we have demonstrated significant relativistic self-focusing (RSF) of a Gaussian electromagnetic beam in the WQP where the Fermi temperature term in the dielectric function is important. For this purpose, we have considered the quantum hydrodynamics model that modifies refractive index of inhomogeneous WQPs with the inclusion of quantum correction through the quantum statistical and diffraction effects in the relativistic regime. Also, to better illustration of the physical difference between warm and cold quantum plasmas and their effect on the RSF, we have derived the envelope equation governing the spot size of X-ray laser beam in Q-plasmas. In addition to the upward ramp density profile, we have found that the quantum effects would be caused much higher oscillation and better focusing of X-ray laser beam in the WQP compared to that of cold quantum case. Our computational results reveal the importance of the use of electrons density profile and Fermi speed in enhancing self-focusing of laser beam.

  17. 4:00pm SSl+PS+TF+AS+NS-TuA7 A Study of the Nucleation of Focused Electron Beam Induced Deposits: Growth Behavior on the

    E-Print Network [OSTI]

    Dunin-Borkowski, Rafal E.

    : Growth Behavior on the Nanometer Scale, W.F. van Dorp, Delft University of Technology, The Netherlands, J University of Technology, The Netherlands Focused electron beam-induced deposition (FEBID) is a technique growth we are able to monitor the growth process in situ. Thin, electron transparent graphite is used

  18. Propagation of ion-acoustic solitons in an electron beam-superthermal plasma system with finite ion-temperature: Linear and fully nonlinear investigation

    SciTech Connect (OSTI)

    Saberian, E. [Department of Physics, Faculty of Sciences, Azarbaijan Shahid Madani University, 53714-161 Tabriz (Iran, Islamic Republic of); Department of Physics, Faculty of Basic Sciences, University of Neyshabur, Neyshabur (Iran, Islamic Republic of); Esfandyari-Kalejahi, A.; Rastkar-Ebrahimzadeh, A.; Afsari-Ghazi, M. [Department of Physics, Faculty of Sciences, Azarbaijan Shahid Madani University, 53714-161 Tabriz (Iran, Islamic Republic of)

    2013-03-15

    The propagation of ion-acoustic (IA) solitons is studied in a plasma system, comprised of warm ions and superthermal (Kappa distributed) electrons in the presence of an electron-beam by using a hydrodynamic model. In the linear analysis, it is seen that increasing the superthermality lowers the phase speed of the IA waves. On the other hand, in a fully nonlinear investigation, the Mach number range and characteristics of IA solitons are analyzed, parametrically and numerically. It is found that the accessible region for the existence of IA solitons reduces with increasing the superthermality. However, IA solitons with both negative and positive polarities can coexist in the system. Additionally, solitary waves with both subsonic and supersonic speeds are predicted in the plasma, depending on the value of ion-temperature and the superthermality of electrons in the system. It is examined that there are upper critical values for beam parameters (i.e., density and velocity) after which, IA solitary waves could not propagate in the plasma. Furthermore, a typical interaction between IA waves and the electron-beam in the plasma is confirmed.

  19. CANCELLED Microwave Ion Source and Beam Injection for an Accelerator-Driven Neut ron Source

    E-Print Network [OSTI]

    2008-01-01

    Abstract An over-dense microwave driven ion source capableregion. Matching of the microwave power from the waveguideperveance. ION SOURCE Microwave source was selected due to

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

    E-Print Network [OSTI]

    2005-01-01

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

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

    E-Print Network [OSTI]

    2006-01-01

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

  2. Biaxial texturing of inorganic photovoltaic thin films using low energy ion beam irradiation during growth

    SciTech Connect (OSTI)

    Groves, James R; De Paula, Raymond F; Hayes, Garrett H; Li, Joel B; Hammond, Robert H; Salleo, Alberto; Clemens, Bruce M

    2010-05-07

    We describe our efforts to control the grain boundary alignment in polycrystalline thin films of silicon by using a biaxially textured template layer of CaF{sub 2} for photovoltaic device applications. We have chosen CaF{sub 2} as a candidate material due to its close lattice match with silicon and its suitability as an ion beam assisted deposition (mAD) material. We show that the CaF{sub 2} aligns biaxially at a thickness of {approx}10 nm and, with the addition of an epitaxial CaF{sub 2} layer, has an in-plane texture of {approx}15{sup o}. Deposition of a subsequent layer of Si aligns on the template layer with an in-plane texture of 10.8{sup o}. The additional improvement of in-plane texture is similar to the behavior observed in more fully characterized IBAD materials systems. A germanium buffer layer is used to assist in the epitaxial deposition of Si on CaF{sub 2} template layers and single crystal substrates. These experiments confirm that an mAD template can be used to biaxially orient polycrystalline Si.

  3. Visualization of expanding warm dense gold and diamond heated rapidly by laser-generated ion beams

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bang, W.; Albright, B. J.; Bradley, P. A.; Gautier, D. C.; Palaniyappan, S.; Vold, E. L.; Cordoba, M. A. Santiago; Hamilton, C. E.; Fernández, J. C.

    2015-09-22

    With the development of several novel heating sources, scientists can now heat a small sample isochorically above 10,000 K. Although matter at such an extreme state, known as warm dense matter, is commonly found in astrophysics (e.g., in planetary cores) as well as in high energy density physics experiments, its properties are not well understood and are difficult to predict theoretically. This is because the approximations made to describe condensed matter or high-temperature plasmas are invalid in this intermediate regime. A sufficiently large warm dense matter sample that is uniformly heated would be ideal for these studies, but has beenmore »unavailable to date. We have used a beam of quasi-monoenergetic aluminum ions to heat gold and diamond foils uniformly and isochorically. For the first time, we visualized directly the expanding warm dense gold and diamond with an optical streak camera. Furthermore, we present a new technique to determine the initial temperature of these heated samples from the measured expansion speeds of gold and diamond into vacuum. We anticipate the uniformly heated solid density target will allow for direct quantitative measurements of equation-of-state, conductivity, opacity, and stopping power of warm dense matter, benefiting plasma physics, astrophysics, and nuclear physics.« less

  4. 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)

    2013-04-19

    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.

  5. Simulation studies for operating electron beam ion trap at very low energy for disentangling edge plasma spectra

    SciTech Connect (OSTI)

    Jin Xuelong; Fei Zejie; Xiao Jun; Lu Di; Hutton, Roger; Zou Yaming [Key Lab of Applied Ion Beam Physics, Ministry of Education, China and Shanghai EBIT laboratory, Modern Physics Institute, Fudan University, Shanghai (China)

    2012-07-15

    Electron beam ion traps (EBITs) are very useful tools for disentanglement studies of atomic processes in plasmas. In order to assist studies on edge plasma spectroscopic diagnostics, a very low energy EBIT, SH-PermEBIT, has been set up at the Shanghai EBIT lab. In this work, simulation studies for factors which hinder an EBIT to operate at very low electron energies were made based on the Tricomp (Field Precision) codes. Longitudinal, transversal, and total kinetic energy distributions were analyzed for all the electron trajectories. Influences from the electron current and electron energy on the energy depression caused by the space charge are discussed. The simulation results show that although the energy depression is most serious along the center of the electron beam, the electrons in the outer part of the beam are more likely to be lost when an EBIT is running at very low energy. Using the simulation results to guide us, we successfully managed to reach the minimum electron beam energy of 60 eV with a beam transmission above 57% for the SH-PermEBIT. Ar and W spectra were measured from the SH-PermEBIT at the apparent electron beam energies (read from the voltage difference between the electron gun cathode and the central drift tube) of 60 eV and 1200 eV, respectively. The spectra are shown in this paper.

  6. Submicro and Nano Structured Porous Materials for the Production of High-Intensity Exotic Radioactive Ion Beams

    E-Print Network [OSTI]

    Fernandes, Sandrina; Stora, Thierry

    2010-01-01

    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...

  7. First plasma of megawatt high current ion source for neutral beam injector of the experimental advanced superconducting tokamak on the test bed

    SciTech Connect (OSTI)

    Hu Chundong; Xie Yahong; Liu Sheng; Xie Yuanlai; Jiang Caichao; Song Shihua; Li Jun; Liu Zhimin

    2011-02-15

    High current ion source is the key part of the neutral beam injector. In order to develop the project of 4 MW neutral beam injection for the experimental advanced superconducting tokamak (EAST) on schedule, the megawatt high current ion source is prestudied in the Institute of Plasma Physics in China. In this paper, the megawatt high current ion source test bed and the first plasma are presented. The high current discharge of 900 A at 2 s and long pulse discharge of 5 s at 680 A are achieved. The arc discharge characteristic of high current ion source is analyzed primarily.

  8. A novel approach to prepare optically active ion doped luminescent materials via electron beam evaporation into ionic liquids

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Richter, K.; Lorbeer, C.; Mudring, A. -V.

    2014-11-10

    A novel approach to prepare luminescent materials via electron-beam evaporation into ionic liquids is presented which even allows doping of host lattices with ions that have a strong size mismatch. Thus, to prove this, MgF2 nanoparticles doped with Eu3+ were fabricated. The obtained nanoparticles featured an unusually high luminescence lifetime and the obtained material showed a high potential for application.

  9. Time-of-flight energy analyzer for the plasma potential measurements by a heavy ion beam diagnostic

    SciTech Connect (OSTI)

    Nedzelskiy, I.S.; Malaquias, A.; Goncalves, B.; Silva, C.; Varandas, C.A.F.; Cabral, J.A.C.

    2004-10-01

    A time-of-flight (TOF) technique for the plasma potential measurements by a heavy ion beam diagnostic (HIBD) with a multiple cell array detector has been elaborated on tokamak ISTTOK as an alternative to the traditional electrostatic energy analyzer. This article describes the design and operation of a four-channel TOF energy analyzer (TOFEA). First results of plasma potential measurements by TOFEA are presented proving the feasibility of this technique in experiments with HIBD.

  10. Transverse field focused system

    DOE Patents [OSTI]

    Anderson, O.A.

    1983-06-01

    It is an object of the invention to provide a transport apparatus for a high current negative-ion beam which will bend the beam around corners through a baffled path in a differential pump or a neutron trap. It is another object of the invention to provide a transport apparatus for a high current negative-ion beam which will allow gas molecules in the beam to exit outwardly from the transport apparatus. A further object of the invention is to provide a multi-stage accelerator for a high current negative-ion beam which will enable acceleration of the beam to very high energy levels with a minimum loss of current carrying capacity. A still further object of the invention is to provide an apparatus for transport or accelertion of a sheet beam of negative ions which is shaped to confine the beam against divergence or expansion.

  11. CW argon-ion laser beams with a central dark region

    SciTech Connect (OSTI)

    Lu Ke Cheng; Sheng Qiu Qin; Liu Zhi Guo; Lu Fu Yun

    1986-08-01

    This paper studies the central dark-region of CW Ar/sup +/ laser beams. The relationship between the dark-region of beam cross section and discharge current has been measured and the spectrum of laser beam has been studied. The cause for the central dark region is discussed.

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

    E-Print Network [OSTI]

    -consistent power plant design for a multi- beam induction linac, final focus and chamber propagationThe Heavy Ion Fusion Virtual National Laboratory The Heavy Ion Path to Fusion Energy Grant Logan Director Heavy-Ion Fusion Virtual National Laboratory Presented to FESAC Workshop on Development Paths

  13. Note: Effect of hot liner in producing {sup 40,48}Ca beam from RIKEN 18-GHz electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Ozeki, K. Higurashi, Y.; Kidera, M.; Nakagawa, T.

    2015-01-15

    In order to produce a high-intensity and stable {sup 48}Ca beam from the RIKEN 18-GHz electron cyclotron resonance ion source, we have begun testing the production of a calcium beam using a micro-oven. To minimize the consumption rate of the material ({sup 48}Ca), we introduced the “hot liner” method and investigated the effect of the liner on the material consumption rate. The micro-oven was first used to produce the {sup 48}Ca beam for experiments in the RIKEN radioisotope beam factory, and a stable beam could be supplied for a long time with low consumption rate.

  14. A PARALLEL-PROPAGATING ALFVENIC ION-BEAM INSTABILITY IN THE HIGH-BETA SOLAR WIND

    SciTech Connect (OSTI)

    Verscharen, Daniel; Bourouaine, Sofiane; Chandran, Benjamin D. G.; Maruca, Bennett A. E-mail: s.bourouaine@unh.edu E-mail: bmaruca@ssl.berkeley.edu

    2013-08-10

    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.

  15. 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.

    2008-02-15

    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.

  16. Efficient evaluation of beam ion confinement in spherical tokamaks Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02139

    E-Print Network [OSTI]

    Egedal, Jan

    of the beam confinement. Losses due to nonadiabatic changes in the magnetic moment are also evaluated. Due: 10.1063/1.1569490# I. INTRODUCTION One of the important methods for heating magnetically confinedEfficient evaluation of beam ion confinement in spherical tokamaks J. Egedal Massachusetts

  17. Efficient evaluation of beam ion confinement in spherical tokamaks Massachusetts Institute of Technology, Plasma Science and Fusion Center, Cambridge, Massachusetts 02139

    E-Print Network [OSTI]

    Egedal, Jan

    of the beam confinement. Losses due to nonadiabatic changes in the magnetic moment are also evaluated. Due: 10.1063/1.1569490 I. INTRODUCTION One of the important methods for heating magnetically confinedEfficient evaluation of beam ion confinement in spherical tokamaks J. Egedal Massachusetts

  18. DESIGN REQUIREMENTS AND OPTIONS FOR FINAL FOCUSING SUPERCONDUCTING MAGNETS

    E-Print Network [OSTI]

    DESIGN REQUIREMENTS AND OPTIONS FOR FINAL FOCUSING SUPERCONDUCTING MAGNETS OF HEAVY-ION DRIVERS L design challenges. The mag- nets are quadrupoles, used for final focusing of beam arrays. Because. Because of the close contact between them, it is in- teresting to explore design concepts that exploit

  19. Influence of different focusing solutions for the TESLA X-ray FEL's on debunching of the electron beam

    E-Print Network [OSTI]

    Influence of different focusing solutions for the TESLA X-ray FEL's on debunching of the electron), Notkestr. 85, 22607 Hamburg, Germany Abstract For SASE-FELs the total undulator length increases different types of focusing for the TESLA X-ray FEL parameters will be discussed. 1. Introduction The TESLA

  20. A 3D Model for Ion Beam Formation and Transport Simulation

    E-Print Network [OSTI]

    Qiang, J.; Todd, D.; Leitner, D.

    2006-01-01

    of the low energy beam line optics of the proposed Rarei o n of the low energy b e a m line optics of the proposed

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

    SciTech Connect (OSTI)

    Jiang, Ximan

    2006-05-18

    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.

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

    SciTech Connect (OSTI)

    Armijo, Julien

    2006-10-01

    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.

  3. Identified particle production and freeze-out properties in heavy-ion collisions at RHIC Beam Energy Scan program

    E-Print Network [OSTI]

    Sabita Das

    2014-12-01

    The first phase of Beam Energy Scan (BES) program at the Relativistic Heavy-Ion Collider (RHIC) was started in the year 2010 with the aim to study the several aspects of the quantum chromodynamics (QCD) phase diagram. The Solenoidal Tracker At RHIC (STAR) detector has taken data at $\\sqrt{s_{NN}} = $ 7.7, 11.5, 19.6, 27, and 39 GeV in Au+Au collisions in the years 2010 and 2011 as part of the BES programme. For these beam energies, we present the results on the particle yields, average transverse mass and particle ratios for identified particles in mid-rapidity ($|y|$ chemical freeze-out dynamics within the framework of a statistical model.

  4. Beam Energy Scaling on Ion-Induced Electron Yield from K+ Impact on Stainless Steel

    E-Print Network [OSTI]

    2006-01-01

    Yield from K + Impact on Stainless Steel Michel Kireeff CovoThe K + ions hit the stainless steel target with energy upenergies hitting stainless steel target obtained from

  5. 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

    2015-01-01

    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.

  6. Resolution Improvement and Pattern Generator Development for the Maskless Micro-Ion-Beam Reduction Lithography System

    E-Print Network [OSTI]

    Jiang, Ximan

    2006-01-01

    ion is 10.0 eV. Assuming the surface charging generates aneV 84 mrad Switching pad and connection wire: 0 volt Insulator 1.0 volt surface chargingeV in this region. Consequently, ion trajectories are very sensitive to the surface charging

  7. Direct Drive Heavy-Ion-Beam Inertial Fusion at High Coupling Efficiency

    E-Print Network [OSTI]

    Logan, B. Grant

    2008-01-01

    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

  8. ION BEAM HEATED TARGET SIMULATIONS FOR WARM DENSE MATTER PHYSICS AND INERTIAL FUSION ENERGY

    E-Print Network [OSTI]

    Barnard, J.J.

    2008-01-01

    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

  9. Trace element content and magnetic properties of commercial HOPG samples studied by ion beam microscopy and SQUID magnetometry

    SciTech Connect (OSTI)

    Spemann, D. Esquinazi, P. Setzer, A.; Böhlmann, W.

    2014-10-15

    In this study, the impurity concentration and magnetic response of nine highly oriented pyrolytic graphite (HOPG) samples with different grades and from different providers were determined using ion beam microscopy and SQUID magnetometry. Apart from sideface contaminations in the as-received state, bulk contamination of the samples in most cases consists of disk-shaped micron-sized particles made of Ti and V with an additional Fe contamination around the grain perimeter. The saturation magnetization typically increases with Fe concentration, however, there is no simple correlation between Fe content and magnetic moment. The saturation magnetization of one, respectively six, out of nine samples clearly exceeds the maximum contribution from pure Fe or Fe{sub 3}C. For most samples the temperature dependence of the remanence decreases linearly with T – a dependence found previously for defect-induced magnetism (DIM) in HOPG. We conclude that apart from magnetic impurities, additional contribution to the ferromagnetic magnetization exists in pristine HOPG in agreement with previous studies. A comparative study between the results of ion beam microscopy and the commonly used EDX analysis shows clearly that EDX is not a reliable method for quantitative trace elemental analysis in graphite, clarifying weaknesses and discrepancies in the element concentrations given in the recent literature.

  10. 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

  11. Self-pinched beam transport experiments Relevant to Heavy Ion Driven inertial fusion energy

    E-Print Network [OSTI]

    1998-01-01

    Heavy Ion Driven Inertial Fusion Energy January 30, 1998 W.C. L . Olson, J. Fusion Energy 1, 309 (1982). "Filamentationof Energy Research [Office of Fusion Energy Science], U . S.

  12. U.S. Heavy Ion Beam Science towards inertial fusion energy

    E-Print Network [OSTI]

    2002-01-01

    Science towards Inertial Fusion Energy B.G. Logan 1), D.Ion Fusion in the U.S. Fusion Energy Sciences Program [25].activities for inertial fusion energy at Lawrence Livermore

  13. THE DEVELOPMENT OF LARGE RECTANGULAR CERAMIC INSULATORS FOR ION ACCELERATORS FOR THE NEUTRAL-BEAM PROGRAM

    E-Print Network [OSTI]

    Paterson, J.A.

    2010-01-01

    OF LARGE RECTANGULAR CERAMIC INSULATORS FOR ION ACCELERATORSj o i n t d e t a i l the Ceramic Shop. Thanks are also dueC. P. Smith, "Machinable Class Ceramics, Nev Materials for

  14. Self-pinched beam transport experiments Relevant to Heavy Ion Driven inertial fusion energy

    E-Print Network [OSTI]

    1998-01-01

    C. L . Olson, J. Fusion Energy 1, 309 (1982). "FilamentationHeavy Ion Driven Inertial Fusion Energy January 30, 1998 W.of Energy Research [Office of Fusion Energy Science], U . S.

  15. 3D characterization of intermetallics in a high pressure die cast Mg alloy using focused ion beam tomography

    SciTech Connect (OSTI)

    Nagasekhar, A.V. [ARC Centre of Excellence for Design in Light Metals, Materials Engineering, University of Queensland, Brisbane, QLD 4072 (Australia); Caceres, C.H., E-mail: c.caceres@uq.edu.au [ARC Centre of Excellence for Design in Light Metals, Materials Engineering, University of Queensland, Brisbane, QLD 4072 (Australia); Kong, C. [Electron Microscope Unit, UNSW Analytical Centre, University of New South Wales, Sydney, NSW 2052 (Australia)

    2010-11-15

    The degree of spatial interconnection of the Mg{sub 17}Al{sub 12} ({beta}-phase) intermetallic in a Mg-9Al-1Zn alloy was assessed through serial sectioning at the centre and near a corner in a casting cross-section. The three dimensional reconstructions showed that the intermetallics were profusely interconnected forming a scaffold-like network over the entire cross-section, but especially near the casting surface. The scale and degree of the interconnection appeared determined by the local concentration of large dendritic grains injected from the shot sleeve. The volume fractions of intermetallics obtained through the 3D reconstruction indicated a higher content of {beta}-phase at the corner regions in comparison with the core. The volume fractions obtained by FIB were consistent with theoretical and experimental values obtained using other techniques.

  16. Advanced Penning-type ion source development and passive beam focusing techniques for an associated particle imaging neutron generator

    E-Print Network [OSTI]

    Sy, Amy

    2013-01-01

    Compact Permanent Magnet Microwave-Driven Neutron Generator.generator. The planned replacement of this electromagnet with a permanent-magnet

  17. Advanced Penning-type ion source development and passive beam focusing techniques for an associated particle imaging neutron generator

    E-Print Network [OSTI]

    Sy, Amy

    2013-01-01

    Accelerator-based neutron generators . . 1.3.1 D-D and D-Tyields . . . 1.4 Compact API generator components . . 2based neutron generator. . . . . D-D and D-T fusion reaction

  18. Electron Holography of Magnetic and Electric Fields in Nanostructured Materials Prepared for TEM Examination Using Focused Ion Beam Milling

    E-Print Network [OSTI]

    Dunin-Borkowski, Rafal E.

    Electron Holography of Magnetic and Electric Fields in Nanostructured Materials Prepared for TEM local angle and spacing carry the desired information about magnetic and electric fields. Electron not be perturbed by stray (fringing) magnetic or electric fields. When examining magnetic nanostructures in cross

  19. Advanced Penning-type ion source development and passive beam focusing techniques for an associated particle imaging neutron generator

    E-Print Network [OSTI]

    Sy, Amy

    2013-01-01

    cusp magnetic field to the plasma confinement and resultantaxial magnetic field and the resultant magnetic confinementaxial magnetic field imposes a type of magnetic confinement

  20. 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)

    2014-04-24

    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.

  1. 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)

    2013-07-11

    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.

  2. Modification of graphene properties due to electron-beam irradiation D. Teweldebrhan and A. A. Balandina

    E-Print Network [OSTI]

    Modification of graphene properties due to electron-beam irradiation D. Teweldebrhan and A. A of changes in the single and bilayer graphene crystal lattice induced by the low and medium energy electron-beam and device fabrication, which rely on the electron microscopy and focused ion beam processing. © 2009

  3. Change in magnetic and structural properties of FeRh thin films by gold cluster ion beam irradiation with the energy of 1.67?MeV/atom

    SciTech Connect (OSTI)

    Koide, T.; Iwase, A. [Department of Materials Science, Osaka Prefecture University, Sakai, Osaka 599-8531 (Japan); Saitoh, Y. [Japan Atomic Energy Agency, Takasaki, Gunma 370-1292 (Japan); Sakamaki, M.; Amemiya, K. [High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801 (Japan); Matsui, T., E-mail: t-matsui@21c.osakafu-u.ac.jp [Research Organization for the 21st Century, Osaka Prefecture University Sakai, Osaka 599-8531 (Japan)

    2014-05-07

    The effect of energetic cluster ion beam irradiation on magnetic and structural properties of FeRh thin films have been investigated. The cluster ions used in the present studies consist of a few gold atoms with the energy of 1.67?MeV/gold atom. Saturation magnetization of the sample irradiated with Au3 cluster ion beam (280?emu/cc) is larger than that for the irradiated sample with Au1 ion beam (240?emu/cc) for the same irradiation ion fluence. These results can also be confirmed by the X-ray magnetic circular dichroism (XMCD) measurement; the XMCD signal for Au3 cluster ion irradiation is larger than that for Au1 ion irradiation. Since the ion beam irradiation induced magnetization of FeRh is significantly correlated with the amount of the lattice defects in the samples, cluster ion beam irradiation can be considered to effectively introduce the lattice defects in B2-type FeRh rather than the single ion beam. Consequently, cluster ion irradiation is better than single ion irradiation for the viewpoint of saturation magnetization, even if the same irradiation energy is deposited in the samples.

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

    E-Print Network [OSTI]

    Wurtele, Jonathan

    and foams) are presented. Experimental configurations include single-pulse planar metallic solid and foam, and a breeder of the tritium component of the fuel. Because of high accelerator efficiency, both indirect drive coupling efficiency (ratio of fuel kinetic energy to beam energy) because of the energy penalty

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

    E-Print Network [OSTI]

    Continetti, Robert E.

    spot was simultaneously irradiated by a beam of quadrupled Nd:YLF laser radiation 261.75 nm to produce with this detector. Experiments were performed using both metal atom cations Ti and Cr produced by laser desorption discovery of new catalysts,2,3 and the human ge- nome project4 have opened ways to attack important prob

  6. Spectral properties of laser-accelerated mid-Z MeV/u ion beams

    SciTech Connect (OSTI)

    Hegelich, B.M.; Albright, B.; Cobble, J.; Gautier, C.; Johnson, R.; Letzring, S.; Fernandez, J.C. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Audebert, P.; Fuchs, J. [Laboratoire pour l'Utilisation des Lasers Intenses, Ecole Polytechnique, 91128 Palaiseau (France); Blazevic, A.; Brambrink, E.; Geissel, M.; Roth, M. [Technische Universitaet Darmstadt, 64289 Darmstadt (Germany); Cowan, T.; Kemp, A. [Physics Department, MS-220, University of Nevada, Reno, Nevada 89557 (United States); Gauthier, J.C. [Centre Lasers Intenses et Applications (CELIA), UMR 5107 CNRS, Universite Bordeaux 1, CEA, Universite Bordeaux 1, 33405 Talence (France); Habs, D.; Schramm, U.; Schreiber, J. [Ludwig-Maximilian Universitaet Muenchen, 85748 Garching (Germany); Karsch, S. [Max-Planck-Institut fuer Quantenoptik, 85748 Garching (Germany)] (and others)

    2005-05-15

    Collimated jets of beryllium, carbon, oxygen, fluorine, and palladium ions with >1 MeV/nucleon energies are observed from the rear surface of thin foils irradiated with laser intensities of up to 5x10{sup 19} W/cm{sup 2}. The normally dominant proton acceleration is suppressed when the target is subjected to Joule heating to remove hydrogen-bearing contaminant. This inhibits screening effects and permits effective energy transfer to and acceleration of heavier ion species. The influence of remnant protons on the spectral shape of the next highest charge-to-mass ratio species is shown. Particle-in-cell simulations confirming the experimental findings are presented.

  7. Optimizing C{sup 4+} and C{sup 5+} beams of the Kei2 electron cyclotron resonance ion source using a special gas-mixing technique

    SciTech Connect (OSTI)

    Drentje, A.G.; Muramatsu, M.; Kitagawa, A.

    2006-03-15

    With the prototype electron cyclotron resonance ion source for the next carbon therapy facility in Japan a series of measurements has been performed in order (a) to find the best condition for producing high beam currents of C{sup 4+} ions, and (b) to study the effect of 'special' gas mixing by using a chemical compound as a feed gas. The effect would then appear as an increase in high charge state production in this case of C{sup 5+} ions. In 'regular' gas-mixing experiments it is well known that an isotopic phenomenon occurs: a heavier isotope of the mixing gas is increasing the production of high charge states of the beam gas ions. A similar isotopic effect has been found in the present experiment: with deuterated methane (CD{sub 4} gas) the C{sup 5+} beam currents are about 10% higher than with regular methane (CH{sub 4} gas). The 'mixing-gas' ratio D (or H) to C can be decreased by choosing, e.g., butane gas; in this case the isotopic effect for C{sup 5+} production is even stronger (>15%). For production of C{sup 4+} ions the isotopic effect appears to be absent. Clearly this is related to the much easier production. It turns out that the relative amount of carbon is much more important: butane gives about 10% higher C{sup 4+}-ion currents than methane.

  8. Present and future perspectives for high energy density physics with intense heavy ion and laser beams

    E-Print Network [OSTI]

    , Germany! accelerator facilities, together with two high energy laser systems: petawatt high energy laserPresent and future perspectives for high energy density physics with intense heavy ion and laser!, Plasmaphysik, Darmstadt, Germany 2 Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt

  9. Spectroscopic ion beam imaging for investigations into magnetic field mapping of a plasma

    E-Print Network [OSTI]

    is the inference of the magnetic field (Bp and Bt) of a magnetically confined plasma from the curvature of a singly changes in magnetic field with time in almost any magnetic confinement device. II. PRINCIPLE OF LOCAL,3 As an HIBP's charged probing ions travel through a plasma, they are deflected by the confining magnetic field

  10. Structure and composition of zirconium carbide thin-film grown by ion beam sputtering for optical applications

    SciTech Connect (OSTI)

    Singh, Amol, E-mail: modimh@rrcat.gov.in; Modi, Mohammed H., E-mail: modimh@rrcat.gov.in; Dhawan, Rajnish, E-mail: modimh@rrcat.gov.in; Lodha, G. S., E-mail: modimh@rrcat.gov.in [X-ray Optics Section, ISU Division, Raja Ramanna Centre for Advanced Technology, Indore-452013 (India)

    2014-04-24

    Thin film of compound material ZrC was deposited on Si (100) wafer using ion beam sputtering method. The deposition was carried out at room temperature and at base pressure of 3×10{sup ?5} Pa. X-ray photoelectron spectroscopy (XPS) measurements were performed for determining the surface chemical compositions. Grazing incidence x-ray reflectivity (GIXRR) measurements were performed to study the film thickness, roughness and density. From GIXRR curve roughness value of the film was found less than 1 nm indicating smooth surface morphology. Films density was found 6.51 g/cm{sup 3}, which is close to bulk density. Atomic force microscopy (AFM) measurements were performed to check the surface morphology. AFM investigation showed that the film surface is smooth, which corroborate the GIXRR data. Figure 2 of the original article PDF file, as supplied to AIP Publishing, contained a PDF processing error. This article was updated on 12 May 2014 to correct that error.

  11. Electron Beam Production by Pyroelectric Crystals

    E-Print Network [OSTI]

    James D. Brownridge; Stephen M. Shafroth

    2002-09-20

    Pyroelectric crystals are used to produce self-focused electron beams with energies greater than 170 keV. No high voltage power supply or electron gun is needed. The system works by simply changing the temperature of a crystal of LiNbO3 or LiTaO3 by about 100oC in dilute gas. Electron beam energy spectra as well as positive-ion-beam energy spectra and profiles are shown. A change in the crystal temperature of 100oC will cause a spontaneous change in polarization. The change in polarization will be manifested by a change in charge on the surface of the crystal. It is this uncompensated charge that produces the electric field, which accelerates the electrons, or the positive ions and gives rise to the plasma, which in turn focuses them. The source of the accelerated electrons or positive ions is gas molecules ionized near the crystal surface. When the crystal surface is negative electrons are accelerated away from it and positive ions are attracted to the surface. These positive ions reduce the net negative charge on the surface thereby reducing the electric field, which causes the electron energy to decrease over time even though the focal properties remain unchanged. When the surface is positive the reverse obtains and the positive ion beam energy decreases over time as well. We will present video clips, photographic and electronic data that demonstrate many of the characteristics and applications of these electron beams.

  12. Current-driven ion-acoustic and potential-relaxation instabilities excited in plasma plume during electron beam welding

    SciTech Connect (OSTI)

    Trushnikov, D. N.; Mladenov, G. M. Koleva, E. G.; Belenkiy, V. Ya. Varushkin, S. V.

    2014-04-15

    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.

  13. Ion source

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA); Ehlers, Kenneth W. (Alamo, CA)

    1984-01-01

    A magnetic filter for an ion source reduces the production of undesired ion species and improves the ion beam quality. High-energy ionizing electrons are confined by the magnetic filter to an ion source region, where the high-energy electrons ionize gas molecules. One embodiment of the magnetic filter uses permanent magnets oriented to establish a magnetic field transverse to the direction of travel of ions from the ion source region to the ion extraction region. In another embodiment, low energy 16 eV electrons are injected into the ion source to dissociate gas molecules and undesired ion species into desired ion species.

  14. 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.

    2002-01-01

    A. Moses, “Inertial fusion energy target output and chamberA. J. Schmitt, et al. , “Fusion energy research with lasers,and focusing,” J. Fusion Energy 1, 309 (1982). [35] D. R.

  15. 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)

    2013-03-11

    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.

  16. Characterization of ultrathin Si02 films formed by direct low-energy ion-beam c. F. Yu, S. S. Todorov, and E. R. Fossum

    E-Print Network [OSTI]

    Fossum, Eric R.

    temperature processes are already replacing many thermal fabrication steps in an attempt to minimize damage to the substrate. Many processes have been proposed as low-tem perature alternatives to thermal oxidationCharacterization of ultrathin Si02 films formed by direct low-energy ion-beam oxidation c. F. Yu, S

  17. 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

  18. Electrochemical Behavior of Disposable Electrodes Prepared by Ion Beam Based Surface Modification for Biomolecular Recognition

    SciTech Connect (OSTI)

    Erdem, A.; Karadeniz, H.; Caliskan, A.; Urkac, E. Sokullu; Oztarhan, A.; Oks, E.; Nikolayev, A.

    2009-03-10

    Many important technological advances have been made in the development of technologies to monitor interactions and recognition events of biomolecules in solution and on solid substrates. The development of advanced biosensors could impact significantly the areas of genomics, proteomics, biomedical diagnostics and drug discovery. In the literature, there have recently appeared an impressive number of intensive designs for electrochemical monitoring of biomolecular recognition. Herein, the influence of ion implanted disposable graphite electrodes on biomolecular recognition and their electrochemical behaviour was investigated.

  19. High-brightness picosecond ion beam source based on BNL Terawatt CO2 laser: Proof-of-principle experiments

    SciTech Connect (OSTI)

    Shkolnikov, Peter

    2012-10-04

    Under the continuing DOE support, we have: o assembled the basic experiment setup and then continued expanding it to include diverse diagnostics and to accommodate gas jet targets in addition to metal foils; o conducted an extensive study of our novel laser, significantly enhanced laser beam diagnostics, and improved relevant laser parameters; o turned our experiments into a truly international endeavor with active collaboration of close to 20 researchers in US, UK, and Germany; o conducted the first ever experiments with proton and ion acceleration by lasers interacting with overcritical plasma of gas jets; o for the first time directly observed radiation pressure acceleration of protons, including quasi-monoenergetic spectra promising for future applications; o for the first time directly observed quasi-stable, bubble-like plasma structures that likely evolved from relativistic laser-plasma solitons (post-solitons). Thus, we have confirmed a strong potential of a picosecond TW CO2 laser as a research tool in laser-plasma science and as a promising vehicle for future applications of laser ion acceleration. This has led to apparent increase of the interest in mid-IR laser ion acceleration. In particular, another major research group began extensive proton acceleration experiments with their own CO2 laser at UCLA. As a result, the mechanisms responsible for laser proton acceleration in gas jets have become somewhat clearer. It is also important to note that modest DOE funding played the role of a seed support ensuring the formation of a multinational research team, whose members contributed its time and equipment with value well in excess of that seed amount.

  20. Anomalous Electron Transport Due to Multiple High Frequency Beam Ion Driven Alfven Eigenmode

    SciTech Connect (OSTI)

    Gorelenkov, N. N.; Stutman, D.; Tritz, K.; Boozer, A.; Delgardo-Aparicio, L.; Fredrickson, E.; Kaye, S.; White, R.

    2010-07-13

    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.

  1. Highly efficient electron vortex beams generated by nanofabricated phase holograms

    SciTech Connect (OSTI)

    Grillo, Vincenzo; Mafakheri, Erfan; Frabboni, Stefano

    2014-01-27

    We propose an improved type of holographic-plate suitable for the shaping of electron beams. The plate is fabricated by a focused ion beam on a silicon nitride membrane and introduces a controllable phase shift to the electron wavefunction. We adopted the optimal blazed-profile design for the phase hologram, which results in the generation of highly efficient (25%) electron vortex beams. This approach paves the route towards applications in nano-scale imaging and materials science.

  2. Production of high brightness H- beam by charge exchange of hydrogen atom beam in sodium jet

    SciTech Connect (OSTI)

    Davydenko, V.; Zelenski, A.; Ivanov, A.; Kolmogorov, A.

    2010-11-16

    Production of H{sup -} beam for accelerators applications by charge exchange of high brightness hydrogen neutral beam in a sodium jet cell is experimentally studied in joint BNL-BINP experiment. In the experiment, a hydrogen-neutral beam with 3-6 keV energy, equivalent current up to 5 A and 200 microsecond pulse duration is used. The atomic beam is produced by charge exchange of a proton beam in a pulsed hydrogen target. Formation of the proton beam is performed in an ion source by four-electrode multiaperture ion-optical system. To achieve small beam emittance, the apertures in the ion-optical system have small enough size, and the extraction of ions is carried out from the surface of plasma emitter with a low transverse ion temperature of {approx}0.2 eV formed as a result of plasma jet expansion from the arc plasma generator. Developed for the BNL optically pumped polarized ion source, the sodium jet target with recirculation and aperture diameter of 2 cm is used in the experiment. At the first stage of the experiment H{sup -} beam with 36 mA current, 5 keV energy and {approx}0.15 cm {center_dot} mrad normalized emittance was obtained. To increase H{sup -} beam current ballistically focused hydrogen neutral beam will be applied. The effects of H{sup -} beam space-charge and sodium-jet stability will be studied to determine the basic limitations of this approach.

  3. Compact microwave ion source for industrial applications

    SciTech Connect (OSTI)

    Cho, Yong-Sub; Kim, Dae-Il; Kim, Han-Sung; Seol, Kyung-Tae; Kwon, Hyeok-Jung; Hong, In-Seok [Proton Engineering Frontier Project, Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of)

    2012-02-15

    A 2.45 GHz microwave ion source for ion implanters has many good properties for industrial application, such as easy maintenance and long lifetime, and it should be compact for budget and space. But, it has a dc current supply for the solenoid and a rf generator for plasma generation. Usually, they are located on high voltage platform because they are electrically connected with beam extraction power supply. Using permanent magnet solenoid and multi-layer dc break, high voltage deck and high voltage isolation transformer can be eliminated, and the dose rate on targets can be controlled by pulse duty control with semiconductor high voltage switch. Because the beam optics does not change, beam transfer components, such as focusing elements and beam shutter, can be eliminated. It has shown the good performances in budget and space for industrial applications of ion beams.

  4. Emittance of short-pulsed high-current ion beams formed from the plasma of the electron cyclotron resonance discharge sustained by high-power millimeter-wave gyrotron radiation

    SciTech Connect (OSTI)

    Razin, S., E-mail: sevraz@appl.sci-nnov.ru; Zorin, V.; Izotov, I. [Institute of Applied Physics of Russian Academy of Sciences, 46 Ulyanova st., 603950 Nizhny Novgorod (Russian Federation)] [Institute of Applied Physics of Russian Academy of Sciences, 46 Ulyanova st., 603950 Nizhny Novgorod (Russian Federation); Sidorov, A.; Skalyga, V. [Institute of Applied Physics of Russian Academy of Sciences, 46 Ulyanova st., 603950 Nizhny Novgorod (Russian Federation) [Institute of Applied Physics of Russian Academy of Sciences, 46 Ulyanova st., 603950 Nizhny Novgorod (Russian Federation); Lobachevsky State University of Nizhny Novgorod (UNN), 23 Gagarina st., 603950 Nizhny Novgorod (Russian Federation)

    2014-02-15

    We present experimental results on measuring the emittance of short-pulsed (?100 ?s) high-current (80–100 mA) ion beams of heavy gases (Nitrogen, Argon) formed from a dense plasma of an ECR source of multiply charged ions (MCI) with quasi-gas-dynamic mode of plasma confinement in a magnetic trap of simple mirror configuration. The discharge was created by a high-power (90 kW) pulsed radiation of a 37.5-GHz gyrotron. The normalized emittance of generated ion beams of 100 mA current was (1.2–1.3) ??mm?mrad (70% of ions in the beams). Comparing these results with those obtained using a cusp magnetic trap, it was concluded that the structure of the trap magnetic field lines does not exert a decisive influence on the emittance of ion beams in the gas-dynamic ECR source of MCI.

  5. 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; Chung, Kyoung-Jae; Hwang, Y. S.; Center for Advance Research in Fusion Reactor Engineering, Seoul National University, Seoul 151-744

    2014-02-15

    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.

  6. Spectroscopy at the high-energy electron beam ion trap (Super EBIT)

    SciTech Connect (OSTI)

    Widmann, K.; Beiersdorfer, P.; Crespo Lopez-Urrutia, J.R.

    1996-07-10

    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.

  7. 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)

    2012-11-27

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

  8. Surface composition, microstructure and corrosion resistance of AZ31 magnesium alloy irradiated by high-intensity pulsed ion beam

    SciTech Connect (OSTI)

    Li, P., E-mail: pli@sqnc.edu.cn [Department of Physics and Information Engineering, Shangqiu Normal University, Shangqiu 476000 (China); Surface Engineering Laboratory, School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China); Lei, M.K., E-mail: surfeng@dlut.edu.cn [Surface Engineering Laboratory, School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China); Zhu, X.P. [Surface Engineering Laboratory, School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China)

    2011-06-15

    High-intensity pulsed ion beam (HIPIB) irradiation of AZ31 magnesium alloy is performed and electrochemical corrosion experiment of irradiated samples is carried out by using potentiodynamic polarization technology in order to explore the effect of HIPIB irradiation on corrosion resistance of magnesium alloy. The surface composition, cross-sectional morphology and microstructure are characterized by using electron probe microanalyzer, optical microscope and transmission electron microscope, respectively. The results indicated that HIPIB irradiation leads to a significant improvement in corrosion resistance of magnesium alloy, in terms of the considerable increase in both corrosion potential and pitting breakdown potential. The microstructural refinement and surface purification induced by HIPIB irradiation are responsible for the improved corrosion resistance. - Research Highlights: {yields} A modified layer about 30 {mu}m thick is obtained by HIPIB irradiation. {yields} Selective ablation of element/impurity phase having lower melting point is observed. {yields} More importantly, microstructural refinement occurred on the irradiated surface. {yields} The modified layer exhibited a significantly improved corrosion resistance. {yields} Improved corrosion resistance is ascribed to the combined effect induced by HIPIB.

  9. FOCUSING AND NEUTRALIZATION OF INTENSE BEAMS Simon S. Yu, Andre Anders, F.M. Bieniosek, Shmuel Eylon, Enrique Henestroza, Prabir Roy,

    E-Print Network [OSTI]

    Gilson, Erik

    is essential for the viability of an economically competitive heavy ion fusion power plant. The physics of theoretical predictions with experiment, the Heavy Ion Fusion Virtual National Laboratory has completed

  10. 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)

    2014-11-15

    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.

  11. Alternating phase focused linacs

    DOE Patents [OSTI]

    Swenson, Donald A. (Los Alamos, NM)

    1980-01-01

    A heavy particle linear accelerator employing rf fields for transverse and ongitudinal focusing as well as acceleration. Drift tube length and gap positions in a standing wave drift tube loaded structure are arranged so that particles are subject to acceleration and succession of focusing and defocusing forces which contain the beam without additional magnetic or electric focusing fields.

  12. Perspective on the Role of Negative Ions and Ion-Ion Plasmas in Heavy Ion Fusion Science, Magnetic Fusion Energy, and Related Fields

    E-Print Network [OSTI]

    Kwan, J.W.

    2008-01-01

    ion drivers for inertial confinement fusion, was achieved.ion driver beams for inertial confinement fusion, they weredriver beams for inertial confinement fusion were successful

  13. Mechanics of nanoscale beams in liquid electrolytes: beam deflections, pull-in instability, and stiction 

    E-Print Network [OSTI]

    Lee, Jae Sang

    2009-05-15

    element method. The effects of ion concentration and electric potentials to the pull-in instability are especially focused by parametric studies with a carbon nanotube cantilever beam. The pull-in voltage of a double-wall carbon nanotube suspended over a...

  14. 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)

    1995-12-31

    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.

  15. Axial magnetic field and toroidally streaming fast ions in the dense plasma focus are natural consequences of conservation laws in the curved axisymmetric geometry of the current sheath

    SciTech Connect (OSTI)

    Auluck, S. K. H.

    2014-10-15

    Direct measurement of axial magnetic field in the PF-1000 dense plasma focus (DPF), and its reported correlation with neutron emission, call for a fresh look at previous reports of existence of axial magnetic field component in the DPF from other laboratories, and associated data suggesting toroidal directionality of fast ions participating in fusion reactions, with a view to understand the underlying physics. In this context, recent work dealing with application of the hyperbolic conservation law formalism to the DPF is extended in this paper to a curvilinear coordinate system, which reflects the shape of the DPF current sheath. Locally unidirectional shock propagation in this coordinate system enables construction of a system of 7 one-dimensional hyperbolic conservation law equations with geometric source terms, taking into account all the components of magnetic field and flow velocity. Rankine-Hugoniot jump conditions for this system lead to expressions for the axial magnetic field and three components of fluid velocity having high ion kinetic energy.

  16. Self-pinched transport of a high ?/? electron beam

    SciTech Connect (OSTI)

    Myers, M. C.; Wolford, M. F.; Sethian, J. D. [U.S. Naval Research Laboratory, Plasma Physics Division, 4555 Overlook Ave., SW, Washington DC 20375 (United States)] [U.S. Naval Research Laboratory, Plasma Physics Division, 4555 Overlook Ave., SW, Washington DC 20375 (United States); Rose, D. V. [Voss Scientific, 418 Washington St. SE, Albuquerque, New Mexico 87108 (United States)] [Voss Scientific, 418 Washington St. SE, Albuquerque, New Mexico 87108 (United States); Hegeler, F. [Commonwealth Technology Inc., 5875 Barclay Drive, Alexandria, Virginia 22315 (United States)] [Commonwealth Technology Inc., 5875 Barclay Drive, Alexandria, Virginia 22315 (United States)

    2013-10-15

    The self-pinched transport of a 0.5 MeV, 18 kA cylindrical electron beam has been studied experimentally and computationally. The relatively low voltage and high current required for materials surface modification applications leads to complicated beam dynamics as the Alfven limit is approached. Transport and focusing of the high ?/? beam was done in a sub-Torr, neutral gas-filled, conducting tube in the ion-focused regime. In this regime, beam space charge forces are progressively neutralized to allow focusing of the beam by its self-magnetic field. The beam exhibits stable envelope oscillations as it is efficiently and reproducibly propagated for distances greater than a betatron wavelength. Experimental results follow the trends seen in 2-D particle-in-cell simulations. Results show that the input electron beam can be periodically focused to a peaked profile with the beam half-current radius decreased by a factor of 2.84. This results in an increase of a factor of 8 in beam current density. This focusing is sufficient to produce desired effects in the surface layers of metallic materials.

  17. Methods of Beam Cooling

    E-Print Network [OSTI]

    Sessler, A. M.

    2008-01-01

    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

  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)

    2011-05-15

    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. 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

    2011-03-06

    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.

  20. Fully kinetic simulations of megajoule-scale dense plasma focus

    SciTech Connect (OSTI)

    Schmidt, A.; Link, A.; Tang, V.; Halvorson, C.; May, M.; Welch, D.; Meehan, B. T.; Hagen, E. C.

    2014-10-15

    Dense plasma focus (DPF) Z-pinch devices are sources of copious high energy electrons and ions, x-rays, and neutrons. Megajoule-scale DPFs can generate 10{sup 12} neutrons per pulse in deuterium gas through a combination of thermonuclear and beam-target fusion. However, the details of the neutron production are not fully understood and past optimization efforts of these devices have been largely empirical. Previously, we reported on the first fully kinetic simulations of a kilojoule-scale DPF and demonstrated that both kinetic ions and kinetic electrons are needed to reproduce experimentally observed features, such as charged-particle beam formation and anomalous resistivity. Here, we present the first fully kinetic simulation of a MegaJoule DPF, with predicted ion and neutron spectra, neutron anisotropy, neutron spot size, and time history of neutron production. The total yield predicted by the simulation is in agreement with measured values, validating the kinetic model in a second energy regime.

  1. Physics with a very first low-energy beta-beam

    E-Print Network [OSTI]

    Cristina Volpe

    2005-10-18

    We describe the importance of having low-energy (10-100 MeV) neutrino beams produced through the decay of boosted radioactive ions (``beta-beams''). We focus on the interest for neutrino-nucleus interaction studies and their impact for astrophysics, nuclear and particle physics. In particular, we discuss the relation to neutrinoless double-beta decay. Finally, we mention the status as far as the feasibility of low-energy beta-beams is concerned.

  2. PPPL3160 Preprint Date: April 1996, UC420 Observations of Neutral Beam and ICRF Tail Ion Losses Due to

    E-Print Network [OSTI]

    act as magnetic spectrometers, dispersing fast ions onto a scintillator, depending upon, ICRF heating tail ions, and alpha particles all heat the plasma and may all be lost through processes the toroidal Alfvén eigenmode (TAE), the kinetic balloon­ ing mode (KBM), alpha driven sawteeth, alpha driven

  3. Perspective on the Role of Negative Ions and Ion-Ion Plasmas in Heavy Ion Fusion Science, Magnetic Fusion Energy, and Related Fields

    E-Print Network [OSTI]

    Kwan, J.W.

    2008-01-01

    and beam diagnostics to an argon beam would then allow an experimental determination of how ion-ion sheaths differ from electron-electrons. Thus, somewhat serendipitously, measuring the parameters of the extracted beams provides a novel diagnostic

  4. 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

    2011-11-20

    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.

  5. Los Alamos Lab: MST: Focus on Facilities

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

    imaging, chemical, and crystallographic analyses of material microstructures with several electron and ion beam instruments.... More about the Electron Microscopy Laboratory...

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

    E-Print Network [OSTI]

    Gilson, Erik

    the reactor cham- ber to an inertial confinement fusion ICF target.9 Another application for NBT is to focus

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

    E-Print Network [OSTI]

    's size and location, and reactive ion etching was used to form an SiO2 template. Nickel electroplating an electroplating process for fabricating nanoscale magnetic structures.2 In this article, we will present a QMD

  8. Single ion implantation for solid state quantum computer development

    SciTech Connect (OSTI)

    Schenkel, Thomas; Meijers, Jan; Persaud, Arun; McDonald, Joseph W.; Holder, Joseph P.; Schneider, Dieter H.

    2001-12-18

    Several solid state quantum computer schemes are based on the manipulation of electron and nuclear spins of single donor atoms in a solid matrix. The fabrication of qubit arrays requires the placement of individual atoms with nanometer precision and high efficiency. In this article we describe first results from low dose, low energy implantations and our development of a low energy (<10 keV), single ion implantation scheme for {sup 31}P{sup q+} ions. When {sup 31}P{sup q+} ions impinge on a wafer surface, their potential energy (9.3 keV for P{sup 15+}) is released, and about 20 secondary electrons are emitted. The emission of multiple secondary electrons allows detection of each ion impact with 100% efficiency. The beam spot on target is controlled by beam focusing and collimation. Exactly one ion is implanted into a selected area avoiding a Poissonian distribution of implanted ions.

  9. Origins of ion irradiation-induced Ga nanoparticle motion on GaAs surfaces

    SciTech Connect (OSTI)

    Kang, M.; Wu, J. H.; Chen, H. Y.; Thornton, K.; Goldman, R. S. [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2136 (United States)] [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2136 (United States); Sofferman, D. L. [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2136 (United States) [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109-2136 (United States); Department of Physics, Adelphi University, Garden City, New York 11530-0701 (United States); Beskin, I. [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109-1040 (United States)] [Department of Physics, University of Michigan, Ann Arbor, Michigan 48109-1040 (United States)

    2013-08-12

    We have examined the origins of ion irradiation-induced nanoparticle (NP) motion. Focused-ion-beam irradiation of GaAs surfaces induces random walks of Ga NPs, which are biased in the direction opposite to that of ion beam scanning. Although the instantaneous NP velocities are constant, the NP drift velocities are dependent on the off-normal irradiation angle, likely due to a difference in surface non-stoichiometry induced by the irradiation angle dependence of the sputtering yield. It is hypothesized that the random walks are initiated by ion irradiation-induced thermal fluctuations, with biasing driven by anisotropic mass transport.

  10. Medical heavy ion accelerator proposals

    SciTech Connect (OSTI)

    Gough, R.A.

    1985-05-01

    For several decades, accelerators designed primarily for research in nuclear and high energy physics have been adapted for biomedical research including radiotherapeutic treatment of human diseases such as pituitary disorders, cancer, and more recently, arteriovascular malformations. The particles used in these treatments include pions, protons and heavier ions such as carbon, neon, silicon and argon. Maximum beam energies must be available to penetrate into an equivalent of about 30 cm of water, requiring treatment beams of 250 to 1000 MeV/nucleon. Certain special treatments of superficial melanoma, however, require that beam energies as low as 70 MeV/nucleon also be available. Intensities must be adequate to complete a 100 rad treatment fraction in about 1 minute. For most heavy ion treatments, this corresponds to 10/sup 7/-10/sup 9/ ions/second at the patient. Because this research is best conducted in a dedicated, hospital-based facility, and because of the clinical need for ultra-high reliability, the construction of new and dedicated facilities has been proposed. Heavy ion accelerators can provide a variety of ions and energies, permitting treatment plans that exploit the properties of the ion best suited to each individual treatment, and that employ radioactive beams (such as /sup 11/C and /sup 19/Ne) to precisely confirm the dose localization. The favored technical approach in these proposals utilizes a conventional, strong-focusing synchrotron capable of fast switching between ions and energies, and servicing multiple treatment rooms. Specialized techniques for shaping the dose to conform to irregularly-shaped target volumes, while simultaneously sparing surrounding, healthy tissue and critical structures, are employed in each treatment room, together with the sophisticated dosimetry necessary for verification, monitoring, and patient safety. 3 refs., 8 figs.

  11. A novel planar ion funnel design for miniature ion optics

    SciTech Connect (OSTI)

    Chaudhary, A.; Amerom, Friso H. W. van; Short, R. T.

    2014-10-01

    The novel planar ion funnel (PIF) design presented in this article emphasizes simple fabrication, assembly, and operation, making it amenable to extreme miniaturization. Simulations performed in SIMION 8.0 indicate that ion focusing can be achieved by using a gradient of electrostatic potentials on concentric metal rings in a plane. A prototype was fabricated on a 35 × 35 mm custom-designed printed circuit board (PCB) with a center hole for ions to pass through and a series of concentric circular metal rings of increasing diameter on the front side of the PCB. Metal vias on the PCB electrically connected each metal ring to a resistive potential divider that was soldered on the back of the PCB. The PIF was tested at 5.5 × 10?? Torr in a vacuum test setup that was equipped with a broad-beam ion source on the front and a micro channel plate (MCP) ion detector on the back of the PIF. The ion current recorded on the MCP anode during testing indicated a 23× increase in the ion transmission through the PIF when electric potentials were applied to the rings. These preliminary results demonstrate the functionality of a 2D ion funnel design with a much smaller footprint and simpler driving electronics than conventional 3D ion funnels. Future directions to improve the design and a possible micromachining approach to fabrication are discussed in the conclusions.

  12. Effect of magnetic-field configuration on the beam intensity from electron cyclotron resonance ion source and RIKEN superconducting electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Nakagawa, T.; Higurashi, Y.; Kidera, M.; Aihara, T.; Kase, M.; Goto, A.; Yano, Y. [RIKEN, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan); SAS Ltd., Kita-shinagawa 5-9-11, Shinjuku-ku, Tokyo (Japan); RIKEN, Hirosawa 2-1, Wako, Saitama 351-0198 (Japan)

    2006-03-15

    We measured the main plasma parameters (density of electron, temperature of electrons, and ion confinement time) as a function of B{sub min} and B{sub inj} with laser ablation technique. We observed that the B{sub min} mainly affects the temperature and density of electrons and all of the three parameters increase with increasing the B{sub inj}. We also observed that the gas pressure of the plasma chamber at the rf injection side became minimum at the optimum value for B{sub min} at fixed gas flow. This result indicates that the ionization efficiency becomes maximum at optimum value for B{sub min}. From these results, it is concluded that the plasma production is strongly dependent on the B{sub min} (plasma generator). We also observed that the B{sub inj} affects the ion confinement time, temperature, and density of electrons. All of the three parameters increase with increasing B{sub inj}.

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

    SciTech Connect (OSTI)

    Henestroza, E.; Eylon, S.; Roy, P.K.; Yu, S.S.; Anders, A.; Bieniosek, F.M.; Greenway, W.G.; Logan, B.G.; MacGill, R.A.; Shuman, D.B.; Vanecek, D.L.; Waldron, W.L.; Sharp, W.M.; Houck, T.L.; Davidson, R.C.; Efthimion, P.C.; Gilson, E.P.; Sefkow, A.B.; Welch, D.R.; Rose, D.V.; Olson, C.L.

    2004-03-14

    In heavy-ion inertial-confinement fusion systems, intense beams of ions must be transported from the exit of the final focus magnet system through the fusion chamber to hit millimeter-sized spots on the target. Effective plasma neutralization of intense ion beams in this final transport is essential for a heavy-ion fusion power plant to be economically competitive. The physics of neutralized drift has been studied extensively with particle-in-cell simulations. To provide quantitative comparisons of theoretical predictions with experiment, the Virtual National Laboratory for Heavy Ion Fusion has completed the construction and has begun experimentation with the Neutralized Transport Experiment (NTX). The experiment consists of three main sections, each with its own physics issues. The injector is designed to generate a very high-brightness, space-charge-dominated potassium beam while still allowing variable perveance by a beam aperturing technique. The magnetic-focusing section, consisting of four pulsed magnetic quadrupoles, permits the study of beam tuning, as well as the effects of phase space dilution due to higher-order nonlinear fields. In the final section, the converging ion beam exiting the magnetic section is transported through a drift region with plasma sources for beam neutralization, and the final spot size is measured under various conditions of neutralization. In this paper, we discuss the design and characterization of the three sections in detail and present initial results from the experiment.

  14. Photo ion spectrometer

    DOE Patents [OSTI]

    Gruen, D.M.; Young, C.E.; Pellin, M.J.

    1989-08-08

    A method and apparatus are described for extracting for quantitative analysis ions of selected atomic components of a sample. A lens system is configured to provide a slowly diminishing field region for a volume containing the selected atomic components, enabling accurate energy analysis of ions generated in the slowly diminishing field region. The lens system also enables focusing on a sample of a charged particle beam, such as an ion beam, along a path length perpendicular to the sample and extraction of the charged particles along a path length also perpendicular to the sample. Improvement of signal to noise ratio is achieved by laser excitation of ions to selected auto-ionization states before carrying out quantitative analysis. Accurate energy analysis of energetic charged particles is assured by using a preselected resistive thick film configuration disposed on an insulator substrate for generating predetermined electric field boundary conditions to achieve for analysis the required electric field potential. The spectrometer also is applicable in the fields of SIMS, ISS and electron spectroscopy. 8 figs.

  15. Improved ion source

    DOE Patents [OSTI]

    Leung, K.N.; Ehlers, K.W.

    1982-05-04

    A magnetic filter for an ion source reduces the production of undesired ion species and improves the ion beam quality. High-energy ionizing electrons are confined by the magnetic filter to an ion source region, where the high-energy electrons ionize gas molecules. One embodiment of the magnetic filter uses permanent magnets oriented to establish a magnetic field transverse to the direction of travel of ions from the ion source region to the ion extraction region. In another embodiment, low energy 16 eV electrons are injected into the ion source to dissociate gas molecules and undesired ion species into desired ion species,

  16. A Space-Charge-Neutralizing Plasma for Beam Drift Compression

    SciTech Connect (OSTI)

    Roy, P.K.; Seidl, P.A.; Anders, A.; Bieniosek, F.M.; Coleman, J.E.; Gilson, E.P.; Greenway, W.; Grote, D.P.; Jung, J.Y.; Leitner, M.; Lidia, S.M.; Logan, B.G.; Sefkow, A.B.; Waldron, W.L.; Welch, D.R.

    2008-08-01

    Simultaneous radial focusing and longitudinal compression of intense ion beams are being studied to heat matter to the warm dense matter, or strongly coupled plasma regime. Higher compression ratios can be achieved if the beam compression takes place in a plasma-filled drift region in which the space-charge forces of the ion beam are neutralized. Recently, a system of four cathodic arc plasma sources has been fabricated and the axial plasma density has been measured. A movable plasma probe array has been developed to measure the radial and axial plasma distribution inside and outside of a {approx} 10 cm long final focus solenoid (FFS). Measured data show that the plasma forms a thin column of diameter {approx} 5 mm along the solenoid axis when the FFS is powered with an 8T field. Measured plasma density of {ge} 1 x 10{sup 13} cm{sup -3} meets the challenge of n{sub p}/Zn{sub b} > 1, where n{sub p} and n{sub b} are the plasma and ion beam density, respectively, and Z is the mean ion charge state of the plasma ions.

  17. PHYSICAL REVIEW E 91, 013109 (2015) Excitation of shear Alfven waves by a spiraling ion beam in a large magnetoplasma

    E-Print Network [OSTI]

    Carter, Troy

    2015-01-01

    has relevance to the low-altitude auroral zone [9], solar wind [10], generation of the fast solar wind a dramatic deconfinement of energetic particles that sig- nificantly impacted the energy efficiency [11], and scattering of energetic ions by Alfv´en waves in solar-flare loops and laboratory plasmas

  18. 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

    2013-01-01

    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, ...

  19. 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

  20. Influence of in-situ annealing ambient on p-type conduction in dual ion beam sputtered Sb-doped ZnO thin films

    SciTech Connect (OSTI)

    Pandey, Sushil Kumar; Kumar Pandey, Saurabh; Awasthi, Vishnu; Mukherjee, Shaibal; Gupta, M.; Deshpande, U. P.

    2013-08-12

    Sb-doped ZnO (SZO) films were deposited on c-plane sapphire substrates by dual ion beam sputtering deposition system and subsequently annealed in-situ in vacuum and in various proportions of O{sub 2}/(O{sub 2} + N{sub 2})% from 0% (N{sub 2}) to 100% (O{sub 2}). Hall measurements established all SZO films were p-type, as was also confirmed by typical diode-like rectifying current-voltage characteristics from p-ZnO/n-ZnO homojunction. SZO films annealed in O{sub 2} ambient exhibited higher hole concentration as compared with films annealed in vacuum or N{sub 2} ambient. X-ray photoelectron spectroscopic analysis confirmed that Sb{sup 5+} states were more preferable in comparison to Sb{sup 3+} states for acceptor-like Sb{sub Zn}-2V{sub Zn} complex formation in SZO films.