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1

ORISE: University Radioactive Ion Beam Consortium  

NLE Websites -- All DOE Office Websites (Extended Search)

UNIRIB UNIRIB Research Overview Physics Topics Equipment Development Education and Training People Publications Overview 2009 Bibliography 2008 Bibliography 2007 Bibliography 2006 Bibliography How to Work With Us Contact Us Oak Ridge Institute for Science Education University Radioactive Ion Beam Consortium The University Radioactive Ion Beam (UNIRIB) consortium is a division of the Oak Ridge Institute for Science and Education (ORISE) focused on cutting-edge nuclear physics research. UNIRIB is a collaborative partnership involving Oak Ridge National Laboratory (ORNL) and nine member universities that leverages national laboratory and university resources to effectively accomplish the U.S. Department of Energy's (DOE) strategic goals in the fundamental structure of nuclei.

2

Laser ion source development at Holifield Radioactive Ion Beam Facility  

Science Conference Proceedings (OSTI)

This report describes the efforts made to develop a resonant-ionization laser ion source based on tunable Ti:sapphire lasers for nuclear physics and astrophysics research at Holifield Radioactive Ion Beam Facility. Three Ti:sapphire lasers have been upgraded with individual pump lasers to eliminate laser power losses due to synchronization delays. Ionization schemes for 14 elements have been obtained. Off-line studies show that the overall efficiency of the laser ion source can be as high as 40%. TaC surface coatings have been investigated for minimizing surface and bulk trapping of the atoms of interest.

Liu, Y.; Havener, C. C.; Beene, J. R. [Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Gottwald, T.; Mattolat, C.; Vane, C. R.; Wendt, K. [Institute of Physics, University of Mainz, D-55099 Mainz (Germany); Howe, J. Y.; Kiggans, J. [Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

2012-02-15T23:59:59.000Z

3

Radioactive Ion Beam Physics and Nuclear Astrophysics in China  

E-Print Network (OSTI)

Based on the intermediate energy radioactive Ion Beam Line in Lanzhou (RIBLL) of Heavy Ion Research Facility in Lanzhou (HIRFL) and Low Energy Radioactive Ion Beam Line (GIRAFFE) of Beijing National Tandem Accelerator Lab (HI13), the radioactive ion beam physics and nuclear astrophysics will be researched in detail. The key scientific problems are: the nuclear structure and reaction for nuclear far from $\\beta$-stability line; the synthesize of new nuclides near drip lines and new super heavy nuclides; the properties of asymmetric nuclear matter with extra large isospin and some nuclear astro- reactions.

Y. G. Ma; X. Z. Cai; W. Q. Shen; W. L. Zhan; Y. L. Ye; W. P. Liu; G. M. Jin; X. H. Zhou; S. W. Xu; L. H. Zuo; S. J. Zhu; Z. H. Liu; J. Meng

2004-10-14T23:59:59.000Z

4

Fusion Induced by Radioactive Ion Beams  

E-Print Network (OSTI)

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.

J. F. Liang; C. Signorini

2005-04-26T23:59:59.000Z

5

High intensity electron beam ion trap for charge state boosting of radioactive ion beams  

SciTech Connect

A high intensity electron beam ion trap under development at LLNL could be adapted for charge state boosting of radioactive ion beams, enabling a substantial reduction in the size and cost of a post-accelerator. We report estimates of the acceptance, ionization time, charge state distribution, emittance, and beam intensity for charge state boosting of radioactive ions in this device. The estimates imply that, for tin isotopes, over 10{sup 10} ions/s can be ionized to q = 40+ with an absolute emittance of approximately 1 (pi) mm mrad at an energy of 30 x q.k.

Marrs, R.

1998-09-30T23:59:59.000Z

6

Thermal-electric numerical simulation of a target for the production of radioactive ion beams  

Science Conference Proceedings (OSTI)

The production target is the core of the facilities aimed at the production of Radioactive Ion Beams. In the facility analysed in this paper, a proton beam directly impinges a target made of uranium carbide that generates the radioactive isotopes needed ... Keywords: ANSYS® software, Coupled field analysis, High temperature, Radiosity solver method, SPES project, Thermal-electric analysis

Giovanni Meneghetti; Mattia Manzolaro; Alberto Andrighetto

2011-05-01T23:59:59.000Z

7

Holifield!Radioactive!Ion!Beam!Facility! Cyclotron!Driver!White!Paper!  

E-Print Network (OSTI)

Holifield!Radioactive!Ion!Beam!Facility! Cyclotron!Driver!White!Paper! ! ! ! ! prepared and design work has progressed. One of the original purposes of the White Paper was a comparison-writing the document now, most of these references would not be relevant. #12;2 1.0 Introduction! ! This!white!paper

8

Study of Nuclear Reactions with 11C and 15O Radioactive Ion Beams  

Science Conference Proceedings (OSTI)

Nuclear reaction study with radioactive ion beams is one of the most exciting research topics in modern nuclear physics. The development of radioactive ion beams has allowed nuclear scientists and engineers to explore many unknown exotic nuclei far from the valley of nuclear stability, and to further our understanding of the evolution of the universe. The recently developed radioactive ion beam facility at the Lawrence Berkeley National Laboratory's 88-inch cyclotron is denoted as BEARS and provides {sup 11}C, {sup 14}O and {sup 15}O radioactive ion beams of high quality. These moderate to high intensity, proton-rich radioactive ion beams have been used to explore the properties of unstable nuclei such as {sup 12}N and {sup 15}F. In this work, the proton capture reaction on {sup 11}C has been evaluated via the indirect d({sup 11}C, {sup 12}N)n transfer reaction using the inverse kinematics method coupled with the Asymptotic Normalization Coefficient (ANC) theoretical approach. The total effective {sup 12}N {yields} {sup 11}C+p ANC is found to be (C{sub eff}{sup 12{sub N}}){sup 2} = 1.83 {+-} 0.27 fm{sup -1}. With the high {sup 11}C beam intensity available, our experiment showed excellent agreement with theoretical predictions and previous experimental studies. This study also indirectly confirmed that the {sup 11}C(p,{gamma}) reaction is a key step in producing CNO nuclei in supermassive low-metallicity stars, bypassing the slow triple alpha process. The newly developed {sup 15}O radioactive ion beam at BEARS was used to study the poorly known level widths of {sup 16}F via the p({sup 15}O,{sup 15}O)p reaction. Among the nuclei in the A=16, T=1 isobaric triad, many states in {sup 16}N and {sup 16}O have been well established, but less has been reported on {sup 16}F. Four states of {sup 16}F below 1 MeV have been identified experimentally: 0{sup -}, 1{sup -}, 2{sup -}, and 3{sup -} (E{sub x} = 0.0, 0.19, 0.42, and 0.72 MeV, respectively). Our study utilized R-matrix analysis and found that the 0- state has a level width of 23.1 {+-} 2.2 keV, and that the broader 1- state has a width of 91.1 {+-} 9.9 keV. The level width of the 2{sup -} state is found to be 3.3 {+-} 0.6 keV which is much narrower than the compiled value of 40 {+-} 30 keV, while a width of 14.1 {+-} 1.7 keV for the 3{sup -} state is in good agreement with the reported value (< 15 keV). These experimental level widths of all four levels are also in accordance with theoretical predictions using single particle shell model calculation.

Lee, Dongwon

2007-05-14T23:59:59.000Z

9

Oxide Target Designs for High Primary Beam Intensities for Future Radioactive Ion Beam Facilities  

SciTech Connect

Oxide targets used nowadays in ISOL facilities can only accommodate up to a few kW incoming beam power because of the targets' moderate operation temperatures and their low thermal conductivities. A generic design to accommodate a 100 kW, 1 GeV proton beam, used as baseline parameters in the ongoing EURISOL-DS project, along with the numerical and experimental tools required for its validation, are reported here. We provide some details on these high-power composite oxide-refractory metal targets and on the proposed arrangement in several sub-units merging into a single ion source.

Stora, T.; Bouquerel, E.; Bruno, L.; Catherall, R.; Fernandes, S.; Kasprowicz, P.; Lettry, J.; Marzari, S.; Noah, E.; Penescu, L.; Wilfinger, R. [AB Department, CERN, CH-1211 Geneva 23 (Switzerland); Singh, B. S. Nara [Department of Physics, University of York, York, Y10 5DD (United Kingdom)

2009-03-10T23:59:59.000Z

10

Nuclear reactions with 11C and 14O radioactive ion beams  

Science Conference Proceedings (OSTI)

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.

Guo, Fanqing

2004-12-09T23:59:59.000Z

11

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

SciTech Connect

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.

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

1990-10-01T23:59:59.000Z

12

Development of Radioactive Ion Beam Purification by Selective Adsorption at the HRIBF  

SciTech Connect

In the past decades many techniques have been developed to reduce isobaric contaminations in ISOL (Isotope Separation On-Line) beams. Another promising method to achieve improved selectivity is employing surface effects in the transfer line between target container and ion source. Thus adsorption materials with suitable atomic structure and polarity can lead to a high chemical selectivity. The principle of selective adsorption has already been employed successfully in the past. Quartz transfer lines are applied on-line at ISOLDE and have been shown to reduce Rb contaminations by 5 orders of magnitude. Since quartz is the only compound that has been tested yet we plan to conduct a broad on-line study of the adsorption behavior of various elements on a range of materials. For testing at the On-Line Test Facility at the Holifield Radioactive Ion Beam Facility (HRIBF) a special target-ion source unit with a variable-temperature transfer line has been constructed in collaboration with the ISOLDE technical group. Based on the design of the ISOLDE prototype unit it was modified to match the unique capabilities of the OLTF. Preliminary results of on-line tests are presented.

Jost, C. [Institut fuer Kernchemie, 55128 Mainz (Germany); Oak Ridge Associated Universities, Oak Ridge, TN 37833 (United States); Carter, H. K.; Goans, R. E.; Griffith, B. O.; Katakam, R.; Reed, C. A.; Spejewski, E. H. [Oak Ridge Associated Universities, Oak Ridge, TN 37833 (United States); Kratz, K.-L. [Institut fuer Kernchemie, 55128 Mainz (Germany); Stora, T. [CERN-ISOLDE, CH-1211, Geneva (Switzerland); Stracener, D. W. [Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)

2009-03-10T23:59:59.000Z

13

The Radioactive Beam Program at Argonne  

E-Print Network (OSTI)

In this talk I will present selected topics of the ongoing radioactive beam program at Argonne and discuss the capabilities of the CARIBU radioactive ion production facility as well as plans for construction of a novel superconducting solenoid spectrometer.

B. B. Back

2006-06-06T23:59:59.000Z

14

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

E-Print Network (OSTI)

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...

Fernandes, Sandrina; Stora, Thierry

2010-01-01T23:59:59.000Z

15

Development of Neutron Detectors for the Next Generation of Radioactive Ion-Beam Facilities  

E-Print Network (OSTI)

The next generation of radioactive ion beam facilities, which will give experimental access to many exotic nuclei, are presently being developed. These facilities will make it possible to study very short lived exotic nuclei with extreme values of isospin far from the line of beta stability. Such nuclei will be produced with very low cross sections and to study them, new detector arrays are being developed. At the SPIRAL facility in GANIL a neutron detector array, the Neutron Wall, is located. In this work the Neutron Wall has been characterized regarding neutron detection efficiency and discrimination between neutrons and gamma rays. The possibility to increase the efficiency by increasing the high voltage of the photomultiplier tubes has also been studied. For SPIRAL2 a neutron detector array, NEDA, is being developed. NEDA will operate in a high gamma-ray background environment which puts a high demand on the quality of discrimination between neutrons and gamma rays. To increase the quality of the discrimination methods pulse-shape discrimination techniques utilizing digital electronics have been developed and evaluated regarding bit resolution and sampling frequency of the ADC. The conclusion is that an ADC with a bit resolution of 12 bits and a sampling frequency of 100 MS/s is adequate for pulse-shape discrimination of neutrons and gamma rays for a neutron energy range of 0.3-12 MeV.

Pär-Anders Söderström

2009-05-13T23:59:59.000Z

16

Development of Neutron Detectors for the Next Generation of Radioactive Ion-Beam Facilities  

E-Print Network (OSTI)

The next generation of radioactive ion beam facilities, which will give experimental access to many exotic nuclei, are presently being developed. These facilities will make it possible to study very short lived exotic nuclei with extreme values of isospin far from the line of beta stability. Such nuclei will be produced with very low cross sections and to study them, new detector arrays are being developed. At the SPIRAL facility in GANIL a neutron detector array, the Neutron Wall, is located. In this work the Neutron Wall has been characterized regarding neutron detection efficiency and discrimination between neutrons and gamma rays. The possibility to increase the efficiency by increasing the high voltage of the photomultiplier tubes has also been studied. For SPIRAL2 a neutron detector array, NEDA, is being developed. NEDA will operate in a high gamma-ray background environment which puts a high demand on the quality of discrimination between neutrons and gamma rays. To increase the quality of the discrimi...

Söderström, Pär-Anders

2009-06-01T23:59:59.000Z

17

Enforcement Letter - Evaluation of Deficiencies Operational Emergency at Building 6000, Holifield Radioactive Ion Beam Facility, Oak Ridge National Laboratory  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

3,2009 3,2009 Dr. Thom Mason President and CEO UT-Battelle Oak Ridge National Laboratory P.O. Box 2008 Oak Ridge, Tennessee 37831-6255 Dear Dr. Mason: The Department of Energy's Office of Enforcement within the Office of Health, Safety and Security has conducted an evaluation of the deficiencies described in Noncompliance Tracking System (NTS) report NTS-ORO--0RNL-XlOPHYSICS-2008-0001, Operational Emergency at Building 6000, Holzfield Radioactive Ion Beam Facility. Our evaluation included a review of the Oak Ridge National Laboratory (ORNL) Management Investigation Team Report dated November 19,2008, the associated corrective action plan, and discussions with site personnel. The subject NTS report described a series of deficiencies at the Holifield Radioactive Ion

18

Broad beam ion implanter  

DOE Patents (OSTI)

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

Leung, Ka-Ngo (Hercules, CA)

1996-01-01T23:59:59.000Z

19

Ion Beam Materials Lab  

NLE Websites -- All DOE Office Websites (Extended Search)

Facilities » Facilities » Ion Beam Materials Lab Ion Beam Materials Lab A new research frontier awaits! Our door is open and we thrive on mutually beneficial partnerships, collaborations that drive innovations and new technologies. April 12, 2012 Ion Beam Danfysik Implanter High Voltage Terminal. Contact Yongqiang Wang (505) 665-1596 Email Devoted to the characterization and modification of surfaces through the use of ion beams The Ion Beam Materials Laboratory (IBML) is a Los Alamos National Laboratory resource devoted to the characterization and modification of surfaces through the use of ion beams. The IBML provides and operates the core facilities, while supporting the design and implementation of specific apparati needed for experiments requested by users of the facility. The result is a facility with

20

Intense ion beam generator  

DOE Patents (OSTI)

Methods and apparatus for producing intense megavolt ion beams are disclosed. In one embodiment, a reflex triode-type pulsed ion accelerator is described which produces ion pulses of more than 5 kiloamperes current with a peak energy of 3 MeV. In other embodiments, the device is constructed so as to focus the beam of ions for high concentration and ease of extraction, and magnetic insulation is provided to increase the efficiency of operation.

Humphries, Jr., Stanley (Ithaca, NY); Sudan, Ravindra N. (Ithaca, NY)

1977-08-30T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Ion beam generating apparatus  

DOE Patents (OSTI)

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.

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

1987-01-01T23:59:59.000Z

22

Ion beam generating apparatus  

DOE Patents (OSTI)

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.

Brown, I.G.; Galvin, J.

1987-12-22T23:59:59.000Z

23

Plasma ion sources and ion beam technology in microfabrications  

E-Print Network (OSTI)

5 Ion source for metallic ion beam generation and thin filmnew plasma source for metallic ion beam generation and metal5: Ion source for metallic ion beam generation and thin film

Ji, Lili

2007-01-01T23:59:59.000Z

24

LANL: Ion Beam Materials Laboratory  

NLE Websites -- All DOE Office Websites (Extended Search)

Ion Beam Materials Laboratory (IBML) is a Los Ion Beam Materials Laboratory (IBML) is a Los Alamos National Laboratory resource devoted to materi- als research through the use of ion beams. Current major research areas include surface characterization through ion beam analysis techniques, surface modification 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 accelerator and a 200 kV ion implanter together with several beam lines. Attached to each beam line is a series of experimental stations that support various research programs. The operation of IBML and its interactions with users are organized around core facilities and experimental stations. The IBML provides and operates the core facilities as well as supports

25

IonBeamMicroFab  

NLE Websites -- All DOE Office Websites (Extended Search)

Ion Beam Manufacture of Microscale Ion Beam Manufacture of Microscale Tools and Components Manufacturing Technologies Sandia Manufacturing Science &Technology's Focused Ion Beam (FIB) laboratory provides an opportunity for research, development and prototyping. Currently, our scientists are devel- oping methods for ion beam sculpting microscale tools, components and devices. This includes shaping of specialty tools such as end-mills, turning tools and indenters. Many of these have been used in ultra-precision machining DOE applications. Additionally, staff are developing the capability to ion mill geo- metrically-complex features and substrates. This includes the ability to sputter predeter- mined curved shapes of various symmetries and periodicities. Capabilities and Expertise * Two custom-built focused ion beam sys-

26

Ion Beam Modification of Materials  

SciTech Connect

This volume contains the proceedings of the 14th International Conference on Ion Beam Modification of Materials, IBMM 2004, and is published by Elsevier-Science Publishers as a special issue of Nuclear Instruments and Methods B. The conference series is the major international forum to present and discuss recent research results and future directions in the field of ion beam modification, synthesis and characterization of materials. The first conference in the series was held in Budapest, Hungary, 1978, and subsequent conferences were held every two years at locations around the Globe, most recently in Japan, Brazil, and the Netherlands. The series brings together physicists, materials scientists, and ion beam specialists from all over the world. The official conference language is English. IBMM 2004 was held on September 5-10, 2004. The focus was on materials science involving both basic ion-solid interaction processes and property changes occurring either during or subsequent to ion bombardment and ion beam processing in relation to materials and device applications. Areas of research included Nanostructures, Multiscale Modeling, Patterning of Surfaces, Focused Ion Beams, Defects in Semiconductors, Insulators and Metals, Cluster Beams, Radiation Effects in Materials, Photonic Devices, Ion Implantation, Ion Beams in Biology and Medicine including New Materials, Imaging, and Treatment.

Averback, B; de la Rubia, T D; Felter, T E; Hamza, A V; Rehn, L E

2005-10-10T23:59:59.000Z

27

ION BEAM COLLIMATOR  

DOE Patents (OSTI)

A device is described for defining a beam of high energy particles wherein the means for defining the beam in the horizontal and vertical dimension are separately adjustable and the defining members are internally cooled. In general, the device comprises a mounting block having a central opening through which the beam is projected, means for rotatably supporting two pairs of beam- forming members, passages in each member for the flow of coolant; the beam- forming members being insulated from each other and the block, and each having an end projecting into the opening. The beam-forming members are adjustable and may be cooperatively positioned to define the beam passing between the end of the members. To assist in projecting and defining the beam, the member ends have individual means connected thereto for indicating the amount of charge collected thereon due to beam interception.

Langsdorf, A.S. Jr.

1957-11-26T23:59:59.000Z

28

ORNL Radioactive Beams for Stellar Explosion Studies  

Science Conference Proceedings (OSTI)

At ORNL, we are using unique radioactive beams to measure scattering, transfer, and capture reactions to help understand exploding stars such as novae, supernovae, and X-ray bursts. Recent results have been obtained with beams of {sup 26}Al, {sup 17}F, and {sup 130,132}Sn, utilizing gas targets, silicon strip detectors, and recoil separators. More exciting work is planned at the future FRIB facility. We are also using synergistic nuclear data evaluations and the Computational Infrastructure for Nuclear Astrophysics to investigate the astrophysical impact of our measurements.

Smith, Michael S. [Physics Division, Oak Ridge National Lab, Oak Ridge, Tennessee, 37831-6354 (United States)

2010-08-12T23:59:59.000Z

29

Particle beam generator using a radioactive source  

DOE Patents (OSTI)

The apparatus of the present invention selects from particles emitted by a radioactive source those particles having momentum within a desired range and focuses the selected particles in a beam having at least one narrow cross-dimension, and at the same time attenuates potentially disruptive gamma rays and low energy particles. Two major components of the present invention are an achromatic bending and focusing system, which includes sector magnets and quadrupole, and a quadrupole doublet final focus system. Permanent magnets utilized in the apparatus are constructed of a ceramic (ferrite) material which is inexpensive and easily machined.

Underwood, D.G.

1991-12-31T23:59:59.000Z

30

Particle beam generator using a radioactive source  

DOE Patents (OSTI)

The apparatus of the present invention selects from particles emitted by a radioactive source those particles having momentum within a desired range and focuses the selected particles in a beam having at least one narrow cross-dimension, and at the same time attenuates potentially disruptive gamma rays and low energy particles. Two major components of the present invention are an achromatic bending and focusing system, which includes sector magnets and quadrupole, and a quadrupole doublet final focus system. Permanent magnets utilized in the apparatus are constructed of a ceramic (ferrite) material which is inexpensive and easily machined.

Underwood, D.G.

1993-03-30T23:59:59.000Z

31

Ion-beam-driven resonant ion cyclotron instability  

SciTech Connect

The resonant ion-beam-driven electrostatic ion cyclotron instability is identified. Measured dispersion relation and onset vs. beam energy and density agree with numerical calculations based on a theory which includes beam acoustic terms. After amplitude saturation, velocity space diffusion of the beam ions is observed. (auth)

Hendel, H.W.; Yamada, M.; Seiler, S.W.; Ikezi, H.

1975-11-01T23:59:59.000Z

32

Positive and Negative Ion Beam Merging System for Neutral Beam ...  

APPLICATIONS OF TECHNOLOGY: Semiconductor manufacturing; Low- and medium-energy ion implantation; Fusion plasma systems requiring neutral beam ...

33

Numerical Simulation of Multicomponent Ion Beam from Ion Sources  

E-Print Network (OSTI)

A program library for numerical simulation of a multicomponent charged particle beam from ion sources is presented. The library is aimed for simulation of high current, low energy multicomponent ion beam from ion source through beamline and realized under the Windows user interface for the IBM PC. It is used for simulation and optimization of beam dynamics and based on successive and consistent application of two methods: the momentum method of distribution function (RMS technique) and particle in cell method. The library has been used to simulate and optimize the transportation of tantalum ion beam from the laser ion source (CERN) and calcium ion beam from the ECR ion source (JINR, Dubna).

Alexandrov, V S; Kazarinov, Yu M; Shevtsov, V P; Shirkov, G D

1999-01-01T23:59:59.000Z

34

ION BEAM FOCUSING MEANS FOR CALUTRON  

DOE Patents (OSTI)

An ion beam focusing arrangement for calutrons is described. It provides a virtual focus of origin for the ion beam so that the ions may be withdrawn from an arc plasma of considerable width providing greater beam current and accuracy. (T.R.H.)

Backus, J.G.

1959-06-01T23:59:59.000Z

35

Ion-beam Plasma Neutralization Interaction Images  

SciTech Connect

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

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

2002-04-09T23:59:59.000Z

36

Focused ion beam direct fabrication of micro-optical elements: features compared with laser beam and electron beam direct writing  

E-Print Network (OSTI)

Three types of focused ion beam machine: focused ion beam milling (FIB milling), focused ion beam lithography (FIB lithography), and focused ion beam direct deposition (FIB deposition), are described in detail to compare ...

Fu, Yongqi

37

Focused helium ion beam milling and deposition  

Science Conference Proceedings (OSTI)

The use of a helium ion microscope with an integrated gas injection system for nanofabrication is explored by demonstrating the milling of fine features into single layered graphene and the controlled deposition of tungsten and platinum wires from gaseous ... Keywords: Beam-induced deposition, Focused ion beam, Gas injection system, Graphene, Helium ion microscope

S. A. Boden; Z. Moktadir; D. M. Bagnall; H. Mizuta; H. N. Rutt

2011-08-01T23:59:59.000Z

38

Molecular Ion Beam Transportation for Low Energy Ion Implantation  

SciTech Connect

A joint research and development of steady state intense boron ion sources for 100's of electron-volt ion implanters has been in progress for the past five years. Current density limitation associated with extracting and transporting low energy ion beams result in lower beam currents that in turn adversely affects the process throughput. The transport channel with electrostatic lenses for decaborane (B{sub 10}H{sub 14}) and carborane (C{sub 2}B{sub 10}H{sub 12}) ion beams transportation was developed and investigated. The significant increase of ion beam intensity at the beam transport channel output is demonstrated. The transport channel simulation, construction and experimental results of ion beam transportation are presented.

Kulevoy, T. V.; Kropachev, G. N.; Seleznev, D. N.; Yakushin, P. E.; Kuibeda, R. P.; Kozlov, A. V.; Koshelev, V. A. [Institute for Theoretical and Experimental Physics, Moscow, 117218 (Russian Federation); Hershcovitch, A.; Johnson, B. M. [Brookhaven National Laboratory, Upton, New York 11973 (United States); Gushenets, V. I.; Oks, E. M. [High Current Electronics Institute Russian Academy of Sciences, Tomsk, 634055 (Russian Federation); Polozov, S. M. [Moscow Engineering Physics Institute, Kashirskoe sh. 31, Moscow, 115409 (Russian Federation); Poole, H. J. [PVI, Oxnard, California 93031-5023 (United States)

2011-01-07T23:59:59.000Z

39

Novel Sources for Focused-ion Beams  

Science Conference Proceedings (OSTI)

... production techniques. This new technique uses a variety of atomic sources to produce highly focused ion beams, with tightly controlled energy. ...

2012-08-14T23:59:59.000Z

40

Electron Beam Ion Trap (EBIT) Facility  

Science Conference Proceedings (OSTI)

... At these temperatures, even the heaviest atoms shed most of their electrons. ... The ions are probed with an intense electron beam, and the emitted ...

2013-06-06T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Plasma formed ion beam projection lithography system  

DOE Patents (OSTI)

A plasma-formed ion-beam projection lithography (IPL) system eliminates the acceleration stage between the ion source and stencil mask of a conventional IPL system. Instead a much thicker mask is used as a beam forming or extraction electrode, positioned next to the plasma in the ion source. Thus the entire beam forming electrode or mask is illuminated uniformly with the source plasma. The extracted beam passes through an acceleration and reduction stage onto the resist coated wafer. Low energy ions, about 30 eV, pass through the mask, minimizing heating, scattering, and sputtering.

Leung, Ka-Ngo (Hercules, CA); Lee, Yung-Hee Yvette (Berkeley, CA); Ngo, Vinh (San Jose, CA); Zahir, Nastaran (Greenbrae, CA)

2002-01-01T23:59:59.000Z

42

Plasma ion sources and ion beam technology in microfabrications  

E-Print Network (OSTI)

and focused ion beam milling cathodic Nanotechnology” 16 (of FIB imaging, milling and deposition………………….45 1.2.3.2. Milling………………………………………………………………..5 1.2.3.3.

Ji, Lili

2007-01-01T23:59:59.000Z

43

Focused Ion Beam/Dual Beam  

Science Conference Proceedings (OSTI)

... It can be used for TEM sample preparation; 3D Slice and View imaging, elemental, and phase analysis; nano-fabrication using electron and ion ...

2012-10-01T23:59:59.000Z

44

Focused Ion beam source method and Apparatus  

DOE Patents (OSTI)

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.

Pellin, Michael J.; Lykke, Keith R.; Lill, Thorsten B.

1998-08-17T23:59:59.000Z

45

Ion Beam Experiment to Simulate Simultaneous Molten Salt ...  

Science Conference Proceedings (OSTI)

Experiments to expose candidate materials to simultaneous molten salt corrosion and ion-beam damage are staged at the Ion Beam Materials Laboratory at Los ...

46

Ion Beam Preparation of Li-Ion Battery Electrodes Li-Ion  

Science Conference Proceedings (OSTI)

One key factor to producing such batteries is the electrode architecture. In order to tune the morphologies of Li-ion battery electrodes, a dual beam Focused Ion ...

47

Flow-through ion beam source  

DOE Patents (OSTI)

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.

Springer, Robert W. (Los Alamos, NM)

1997-01-01T23:59:59.000Z

48

Ion beam processing of advanced electronic materials  

SciTech Connect

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)

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

1989-01-01T23:59:59.000Z

49

Intense ion beam research at Los Alamos  

SciTech Connect

Two new interdisciplinary programs are underway at Los Alamos involving the physics and technology of intense light ion beams. In contrast to high-power ICF applications, the LANL effort concentrates on the development of relatively low-voltage (50 to 800 kV) and long-pulsewidth (0.1 to 1 {mu}s) beams. The first program involves the 1.2 MV, 300-kJ Anaconda generator which has been fitted with an extraction ion diode. Long pulsewidth ion beams have been accelerated, propagated, and extracted for a variety of magnetic field conditions. The primary application of this beam is the synthesis of novel materials. Initial experiments on the congruent evaporative deposition of metallic and ceramic thin films are reported. The second program involves the development of a 120-keV, 50-kA, 1-{mu}s proton beam for the magnetic fusion program as an ion source for an intense diagnostic neutral beam. Ultra-bright, pulsed neutral beams will be required to successfully measure ion temperatures and thermalized alpha particle energy distributions in large, dense, ignited tokamaks such as ITER.

Rej, D.J.; Bartsch, R.R.; Davis, H.A.; Faehl, R.J.; Gautier, D.C.; Greenly, J.B.; Henins, I.; Linton, T.W.; Muenchausen, R.E.; Waganaar, W.J.

1992-07-01T23:59:59.000Z

50

Intense ion beam research at Los Alamos  

Science Conference Proceedings (OSTI)

Two new interdisciplinary programs are underway at Los Alamos involving the physics and technology of intense light ion beams. In contrast to high-power ICF applications, the LANL effort concentrates on the development of relatively low-voltage (50 to 800 kV) and long-pulsewidth (0.1 to 1 {mu}s) beams. The first program involves the 1.2 MV, 300-kJ Anaconda generator which has been fitted with an extraction ion diode. Long pulsewidth ion beams have been accelerated, propagated, and extracted for a variety of magnetic field conditions. The primary application of this beam is the synthesis of novel materials. Initial experiments on the congruent evaporative deposition of metallic and ceramic thin films are reported. The second program involves the development of a 120-keV, 50-kA, 1-{mu}s proton beam for the magnetic fusion program as an ion source for an intense diagnostic neutral beam. Ultra-bright, pulsed neutral beams will be required to successfully measure ion temperatures and thermalized alpha particle energy distributions in large, dense, ignited tokamaks such as ITER.

Rej, D.J.; Bartsch, R.R.; Davis, H.A.; Faehl, R.J.; Gautier, D.C.; Greenly, J.B.; Henins, I.; Linton, T.W.; Muenchausen, R.E.; Waganaar, W.J.

1992-01-01T23:59:59.000Z

51

A pencil beam algorithm for helium ion beam therapy  

Science Conference Proceedings (OSTI)

Purpose: To develop a flexible pencil beam algorithm for helium ion beam therapy. Dose distributions were calculated using the newly developed pencil beam algorithm and validated using Monte Carlo (MC) methods. Methods: The algorithm was based on the established theory of fluence weighted elemental pencil beam (PB) kernels. Using a new real-time splitting approach, a minimization routine selects the optimal shape for each sub-beam. Dose depositions along the beam path were determined using a look-up table (LUT). Data for LUT generation were derived from MC simulations in water using GATE 6.1. For materials other than water, dose depositions were calculated by the algorithm using water-equivalent depth scaling. Lateral beam spreading caused by multiple scattering has been accounted for by implementing a non-local scattering formula developed by Gottschalk. A new nuclear correction was modelled using a Voigt function and implemented by a LUT approach. Validation simulations have been performed using a phantom filled with homogeneous materials or heterogeneous slabs of up to 3 cm. The beams were incident perpendicular to the phantoms surface with initial particle energies ranging from 50 to 250 MeV/A with a total number of 10{sup 7} ions per beam. For comparison a special evaluation software was developed calculating the gamma indices for dose distributions. Results: In homogeneous phantoms, maximum range deviations between PB and MC of less than 1.1% and differences in the width of the distal energy falloff of the Bragg-Peak from 80% to 20% of less than 0.1 mm were found. Heterogeneous phantoms using layered slabs satisfied a {gamma}-index criterion of 2%/2mm of the local value except for some single voxels. For more complex phantoms using laterally arranged bone-air slabs, the {gamma}-index criterion was exceeded in some areas giving a maximum {gamma}-index of 1.75 and 4.9% of the voxels showed {gamma}-index values larger than one. The calculation precision of the presented algorithm was considered to be sufficient for clinical practice. Although only data for helium beams was presented, the performance of the pencil beam algorithm for proton beams was comparable. Conclusions: The pencil beam algorithm developed for helium ions presents a suitable tool for dose calculations. Its calculation speed was evaluated to be similar to other published pencil beam algorithms. The flexible design allows easy customization of measured depth-dose distributions and use of varying beam profiles, thus making it a promising candidate for integration into future treatment planning systems. Current work in progress deals with RBE effects of helium ions to complete the model.

Fuchs, Hermann; Stroebele, Julia; Schreiner, Thomas; Hirtl, Albert; Georg, Dietmar [Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna, 1090 Vienna (Austria); Department of Radiation Oncology, Medical University of Vienna/AKH Vienna, 1090 Vienna (Austria) and Comprehensive Cancer Center, Medical University of Vienna/AKH Vienna, 1090 Vienna (Austria); Department of Radiation Oncology, Medical University of Vienna/AKH Vienna (Austria) and Comprehensive Cancer Center, Medical University of Vienna/AKH Vienna, 1090 Vienna (Austria); PEG MedAustron, 2700 Wiener Neustadt (Austria); Department of Nuclear Medicine, Medical University of Vienna, 1090 Vienna (Austria); Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna, 1090 Vienna (Austria); Department of Radiation Oncology, Medical University of Vienna/AKH Vienna, 1090 Vienna (Austria) and Comprehensive Cancer Center, Medical University of Vienna/AKH Vienna, 1090 Vienna (Austria)

2012-11-15T23:59:59.000Z

52

Radioactive ion beam research at LLNL  

DOE Green Energy (OSTI)

In this paper we discuss efforts underway at LLNL to develop the technology for the measurement of proton and alpha-particle reactions with unstable nuclei which are necessary for understanding the nucleosynthesis and energy generation in hot hydrogen-burning environments. 16 refs., 5 figs.

Mathews, G.J.; Bauer, R.W.; Haight, R.C.; Sale, K.E.

1985-08-01T23:59:59.000Z

53

Projectile fragmentation of radioactive beams of {sup 68}Ni, {sup 69}Cu, and {sup 72}Zn  

Science Conference Proceedings (OSTI)

The fragment production cross sections of secondary neutron-rich beams of {sup 68}Ni, {sup 69}Cu, and {sup 72}Zn isotopes at energies of about 95A MeV have been measured. We compare the measured cross sections to EPAX, an empirical parametrization of fragmentation cross sections. A reasonable agreement of the experimental data and EPAX predictions suggests that an EPAX parametrization used for stable beams seems to be valid for unstable neutron-rich ion beams. EPAX tends to overestimate the yields of neutron-rich isotopes. This problem is amplified when neutron-rich radioactive beams are employed, leading to overly optimistic estimates of the production of neutron-rich isotopes.

Lukyanov, S.; Lobastov, S. P.; Tarasov, O. B. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, RU-141980 Dubna, Moscow region (Russian Federation); Mocko, M. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States); Andronenko, L.; Andronenko, M. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); PNPI, Gatchina, Leningrad district RU-188300 (Russian Federation); Bazin, D.; Gade, A. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Famiano, M. A. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Department of Physics, Western Michigan University, Kalamazoo, Michigan 49008 (United States); Lynch, W. G.; Rogers, A. M.; Tsang, M. B.; Zegers, R. G. T. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States); Verde, G. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); INFN, Sezione di Catania, 64 Via Santa Sofia, I-95123 Catania (Italy); Wallace, M. S. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2009-07-15T23:59:59.000Z

54

Multiple Electron Stripping of Heavy Ion Beams  

DOE Green Energy (OSTI)

One approach being explored as a route to practical fusion energy uses heavy ion beams focused on an indirect drive target. Such beams will lose electrons while passing through background gas in the target chamber, and therefore it is necessary to assess the rate at which the charge state of the incident beam evolves on the way to the target. Accelerators designed primarily for nuclear physics or high energy physics experiments utilize ion sources that generate highly stripped ions in order to achieve high energies economically. As a result, accelerators capable of producing heavy ion beams of 10 to 40 Mev/amu with charge state 1 currently do not exist. Hence, the stripping cross-sections used to model the performance of heavy ion fusion driver beams have, up to now, been based upon theoretical calculations. We have investigated experimentally the stripping of 3.4 Mev/amu Kr 7+ and Xe +11 in N2; 10.2 MeV/amu Ar +6 in He, N2, Ar and Xe; 19 MeV/amu Ar +8 in He, N2, Ar and Xe; 30 MeV He 1 + in He, N2, Ar and Xe; and 38 MeV/amu N +6 in He, N2, Ar and Xe. The results of these measurements are compared with the theoretical calculations to assess their applicability over a wide range of parameters.

D. Mueller; L. Grisham; I. Kaganovich; R. L. Watson; V. Horvat; K. E. Zaharakis; Y. Peng

2002-06-25T23:59:59.000Z

55

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

SciTech Connect

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

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

1992-07-01T23:59:59.000Z

56

Synthesis of transactinide nuclei in cold fusion reactions using radioactive beams  

SciTech Connect

Chances of synthesis of transactinide nuclei in cold fusion reactions (one-neutron-out reactions) using radioactive beams are evaluated. Because in most of the cases intensities of radioactive beams are significantly less than those of the stable beams, reactions with the greatest radioactive-beam intensities for the particular elements are considered. The results are compared with the recent ones obtained by Loveland [Phys. Rev. C 76, 014612 (2007)], who investigated the same nuclei.

Smolanczuk, Robert [Theoretical Physics Department, Soltan Institute for Nuclear Studies, Hoza 69, PL-00-681 Warszawa (Poland)

2010-06-15T23:59:59.000Z

57

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

SciTech Connect

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

Garrett, J.D. [ed.

1992-12-31T23:59:59.000Z

58

Nanofabrication using focused ion beam  

E-Print Network (OSTI)

Deposition 47 3.2.3 Photolithography 48 3.2.4 Al Dissolution, Advanced Scanning Electron Microscope Specimen Preparation and Other Methods 50 3.2.4.1 Al Dissolution 50 3.2.4.2 Advanced Scanning Electron Microscope Specimen Preparation 51 3... . Measurements performed included in-situ resistometric measurements, which provided milled depth information by monitoring the resistance change of a metal track while ion milling it. The reproducibly of this method was confirmed by repeating experiments...

Latif, Adnan

59

Focused ion beam micromilling and articles therefrom  

DOE Patents (OSTI)

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.

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

1998-06-30T23:59:59.000Z

60

Ferroelectric Plasma Source for Heavy Ion Beam Charge Neutralization  

E-Print Network (OSTI)

Heavy Ion Beam Driven Fusion Reactor Study”, KfK-3480,a possible heavy ion fusion reactor design [1]. The final

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Novel Sources for Focused-ion Beams Laboratory  

Science Conference Proceedings (OSTI)

... is focused on developing novel sources of ion ... with a wide range of ionic species and beam energies. ... with the liquid metal ion source replaced by a ...

2011-09-24T23:59:59.000Z

62

MULTIPLE ELECTRON BEAM ION PUMP AND SOURCE  

DOE Patents (OSTI)

A vacuum pump is designed which operates by ionizing incoming air and by withdrawing the ions from the system by means of electrical fields. The apparatus comprises a cylindrical housing communicable with the vessel to be evacuated and having a thin wall section in one end. Suitable coils provide a longitudinal magnetic field within the cylinder. A broad cathode and an anode structure is provided to establish a plurality of adjacent electron beams which are parallel to the cylinder axis. Electron reflector means are provided so that each of the beams constitutes a PIG or reflex discharge. Such structure provides a large region in which incoming gas molecules may be ionized by electron bombardment. A charged electrode assembly accelerates the ions through the thin window, thereby removing the gas from the system. The invention may also be utilized as a highly efficient ion source. (AEC)

Ellis, R.E.

1962-02-27T23:59:59.000Z

63

Focused Ion Beam Milling (FIB) Information at NIST  

Science Conference Proceedings (OSTI)

Focused Ion Beam Milling (FIB) Information at NIST. Analysis of 3D Elemental Mapping Artifacts in Biological Specimens ...

2010-10-05T23:59:59.000Z

64

Ion beam assisted deposition of thermal barrier coatings ...  

... Energy Innovation Portal on Google; Bookmark Ion beam assisted deposition of thermal barrier coatings - Energy Innovation Portal on Delicious ...

65

First experiment on fission transients in highly fissile spherical nuclei produced by fragmentation of radioactive beams  

E-Print Network (OSTI)

We report on a novel experimental approach for studying the dissipative spreading of collective motion in a meta-stable nuclear system, using, for the first time, highly fissile nuclei with spherical shape. This was achieved by fragmentation of 45 radioactive heavy-ion beams at GSI, Darmstadt. The use of inverse kinematics and a dedicated experimental set-up allowed for the identification in atomic number of both fission fragments. From the width of their charge distributions, a transient time of (3.3 +/- 0.7) 10-21 s is deduced for initially spherical nuclei.

C. Schmitt; P. N. Nadtochy; A. Heinz; B. Jurado; A. Kelic; K. -H. Schmidt

2007-02-12T23:59:59.000Z

66

Unexpected results in neutron-rich radioactive beams induced fusion  

Science Conference Proceedings (OSTI)

The fission-fragment beams at HRIBF provide a unique opportunity for studying the mechanisms of fusion involving nuclei with large neutron excess. To explore the role of transfer couplings, fusion excitation functions have been measured using neutron-rich radioactive $^{132}$Sn beams incident on $^{40}$Ca and $^{58}$Ni targets. The sub-barrier fusion enhancement for $^{132}$Sn+$^{40}$Ca is larger than that for $^{132}$Sn+$^{58}$Ni although the neutron transfer Q-values are similar for the two reactions. The fusion excitation function for $^{46}$Ti+$^{124}$Sn has been measured in an attempt to resolve the differences observed in $^{132}$Sn+$^{40}$Ca and $^{132}$Sn+$^{58}$Ni.

Liang, J Felix [ORNL] [ORNL

2013-01-01T23:59:59.000Z

67

High-energy accelerator for beams of heavy ions  

DOE Patents (OSTI)

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.

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

1978-01-01T23:59:59.000Z

68

Ion Beam Collimation For Improved Resolution In Associated Particle Imaging  

Science Conference Proceedings (OSTI)

Beam spot size on target for a Penning ion source has been measured under different source operating pressures as a function of the extraction channel length and beam energy. A beam halo/core structure was observed for ion extraction at low extraction voltages, and was greatly reduced at higher beam energy. Collimation through use of longer extraction channels results in reduced ion current on target; the resultant reduction in neutron yield for an API system driven by such an ion source can be compensated for by use of even higher beam energies.

Sy, Amy [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Department of Nuclear Engineering, University of California, Berkeley, Berkeley, CA 94720 (United States); Ji Qing [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States)

2011-06-01T23:59:59.000Z

69

Plasma and ion beam processing at Los Alamos  

SciTech Connect

Efforts are underway at Los Alamos National Laboratory to utilize plasma and intense ion beam science and technology of the processing of advanced materials. A major theme involves surface modification of materials, e.g., etching, deposition, alloying, and implantation. In this paper, we concentrate on two programs, plasma source ion implantation and high-intensity pulsed ion beam deposition.

Rej, D.J.; Davis, H.A.; Henins, I. [and others

1994-07-01T23:59:59.000Z

70

Ion beam surface treatment: A new technique for thermally modifying surfaces using intense, pulsed ion beams  

Science Conference Proceedings (OSTI)

The emerging capability to produce high average power (10--300 kW) pulsed ion beams at 0.2{minus}2 MeV energies is enabling us to develop a new, commercial-scale thermal surface treatment technology called Ion Beam Surface Treatment (IBEST). This new technique uses high energy, pulsed ({le}500 ns) ion beams to directly deposit energy in the top 1--20 micrometers of the surface of any material. The depth of treatment is controllable by varying the ion energy and species. Deposition of the energy in a thin surface layer allows melft of the layer with relatively small energies (1--10J/cm2) and allows rapid cooling of the melted layer by thermal conduction into the underlying substrate. Typical cooling rates of this process (109 K/sec) are sufficient to cause amorphous layer formation and the production of non-equilibrium microstructures (nanocrystalline and metastable phases). Results from initial experiments confirm surface hardening, amorphous layer and nanocrystalline grain size formation, corrosion resistance in stainless steel and aluminum, metal surface polishing, controlled melt of ceramic surfaces, and surface cleaning and oxide layer removal as well as surface ablation and redeposition. These results follow other encouraging results obtained previously in Russia using single pulse ion beam systems. Potential commercialization of this surface treatment capability is made possible by the combination of two new technologies, a new repetitive high energy pulsed power capability (0.2{minus}2MV, 25--50 kA, 60 ns, 120 Hz) developed at SNL, and a new repetitive ion beam system developed at Cornell University.

Stinnett, R.W.; Buchheit, R.G.; Neau, E.L. [and others

1995-08-01T23:59:59.000Z

71

Important atomic physics issues for ion beam fusion  

SciTech Connect

This paper suggests several current atomic physics questions important to ion beam fusion. Among the topics discussed are beam transport, beam-target interaction, and reactor design. The major part of the report is discussion concerning areas of research necessary to better understand beam-target interactions. (JDH)

Bangerter, R.O.

1985-03-19T23:59:59.000Z

72

Nanostructure fabrication by electron and ion beam patterning of nanoparticles  

E-Print Network (OSTI)

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, ...

Kong, David Sun, 1979-

2004-01-01T23:59:59.000Z

73

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

Science Conference Proceedings (OSTI)

A number of intense ion beams applications are emerging requiring repetitive high-average-power beams. These applications include ablative deposition of thin films, rapid melt and resolidification for surface property enhancement, advanced diagnostic neutral beams for the next generation of Tokamaks, and intense pulsed-neutron sources. We are developing a 200-250 keV, 15 kA, 1 {mu}s duration, 1-30 Hz intense ion beam accelerator to address these applications.

Davis, H.A.; Olson, J.C.; Reass, W.A. [Los Alamos National Lab., NM (United States); Coates, D.M.; Hunt, J.W.; Schleinitz, H.M. [Du Pont de Nemours (E.I.) and Co., Wilmington, DE (United States). Central Research and Development Dept.; Lovberg, R.H. [California Univ., San Diego, La Jolla, CA (United States); Greenly, J.B. [Cornell Univ., Ithaca, NY (United States). Lab. of Plasma Studies

1996-07-01T23:59:59.000Z

74

Materials processing with intense pulsed ion beams  

SciTech Connect

We review research investigating the application of intense pulsed ion beams (IPIBs) for the surface treatment and coating of materials. The short range (0.1-10 {mu}m) and high-energy density (1-50 J/cm{sup 2}) of these short-pulsed ({le} 1 {mu}s) beams (with ion currents I = 5 - 50 kA, and energies E = 100 - 1000 keV) make them ideal to flash-heat a target surface, similar to the more familiar pulsed laser processes. IPIB surface treatment induces rapid melt and solidification at up to 10{sup 10} K/s to cause amorphous layer formation and the production of non-equilibrium microstructures. At higher energy density the target surface is vaporized, and the ablated vapor is condensed as coatings onto adjacent substrates or as nanophase powders. Progress towards the development of robust, high-repetition rate IPIB accelerators is presented along with economic estimates for the cost of ownership of this technology.

Rej, D.J.; Davis, H.A.; Olson, J.C. [and others

1996-12-31T23:59:59.000Z

75

ABSTRACT: Ion-Induced Damage Accumulation and Electron-Beam ...  

Science Conference Proceedings (OSTI)

Jun 27, 2007... Ion-Induced Damage Accumulation and Electron-Beam-Enhanced ... damage accumulation in strontium titanate from 1.0 MeV Au irradiation

76

A new luminescence beam profile monitor for intense proton and heavy ion beams  

DOE Green Energy (OSTI)

A new luminescence beam profile monitor is realized in the polarized hydrogen gas jet target at the Relativistic Heavy Ion Collider (RHIC) facility. In addition to the spin polarization of the proton beam being routinely measured by the hydrogen gas jet, the luminescence produced by beam-hydrogen excitation leads to a strong Balmer series lines emission. A selected hydrogen Balmer line is spectrally filtered and imaged to produce the transverse RHIC proton beam shape with unprecedented details on the RHIC beam profile. Alternatively, when the passage of the high energy RHIC gold ion beam excited only the residual gas molecules in the beam path, sufficient ion beam induced luminescence is produced and the transverse gold ion beam profile is obtained. The measured transverse beam sizes and the calculated emittances provide an independent confirmation of the RHIC beam characteristics and to verify the emittance conservation along the RHIC accelerator. This optical beam diagnostic technique by making use of the beam induced fluorescence from injected or residual gas offers a truly noninvasive particle beam characterization, and provides a visual observation of proton and heavy ion beams. Combined with a longitudinal bunch measurement system, a 3-dimensional spatial particle beam profile can be reconstructed tomographically.

Tsang,T.; Bellavia, S.; Connolly, R.; Gassner, D.; Makdisi, Y.; Russo, T.; Thieberger, P.; Trbojevic, D.; Zelenski, A.

2008-10-01T23:59:59.000Z

77

Caborane beam from ITEP Bernas ion source for semiconductor implanters  

SciTech Connect

A joint research and development of steady state intense boron ion sources for hundreds of electron-volt ion implanters has been in progress for the past 5 years. The difficulties of extraction and transportation of low energy boron beams can be solved by implanting clusters of boron atoms. In Institute for Theoretical and Experimental Physics (ITEP) the Bernas ion source successfully generated the beam of decaborane ions. The carborane (C{sub 2}B{sub 10}H{sub 12}) ion beam is more attractive material due to its better thermal stability. The results of carborane ion beam generation are presented. The result of the beam implantation into the silicon wafer is presented as well.

Seleznev, D.; Hershcovitch, A.; Kropachev, G.; Kozlov, A.; Kuibeda, R.; Koshelev, V.; Kulevoy, T.; Jonson, B.; Poole, J.; Alexeyenko, O.; Gurkova, E.; Oks, E.; Gushenets, V.; Polozov, S.; Masunov, E.

2010-02-01T23:59:59.000Z

78

Observation of Beam ION Instability in Spear3  

SciTech Connect

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.

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

2011-12-14T23:59:59.000Z

79

Neutral beam based on positive ions with direct energy conversion  

DOE Green Energy (OSTI)

Positive ions can make efficient neutral beams when direct energy conversion is incorporated at energies up to 150 keV for D/sup 0/, 225 keV for T/sup 0/ and 300 keV for /sup 3/He/sup 0/. Above these energies the efficiency is low (<50%) and falling rapidly, requiring other means for making neutral beams such as negative ions. The virtues of /sup 3/He/sup 0/ beams as a heater are discussed. The role of direct conversion is discussed and the various conversion concepts and the experimental data base are reviewed. The development problems facing direct conversion are: space charge handling, secondary and primary electron suppression, and the fractional energy ions. The next step in the development of efficient neutral beams based on positive ions is argued to be a developmental beam which integrates an advanced ion source with a neutralizer, cryopump, direct converter, heat removal system, and power conditioning system.

Moir, R.W.; Barr, W.L.; Blum, A.S.; Hamilton, G.W.

1977-12-01T23:59:59.000Z

80

Beam Compression in Heavy-Ion Induction Linacs  

SciTech Connect

The Heavy-Ion Fusion Sciences Virtual National Laboratory is pursuing an approach to target heating experiments in the Warm Dense Matter regime, using space-charge-dominated ion beams that are simultaneously longitudinally bunched and transversely focused. Longitudinal beam compression by large factors has been demonstrated in the LBNL Neutralized Drift Compression Experiment (NDCX) experiment with controlled ramps and forced neutralization. The achieved peak beam current and energy can be used in experiments to heat targets and create warm dense matter. Using an injected 30 mA K{sup +} ion beam with initial kinetic energy 0.3 MeV, axial compression leading to {approx}50x current amplification and simultaneous radial focusing to beam radii of a few mm have led to encouraging energy deposition approaching the intensities required for eV-range target heating experiments. We discuss experiments that are under development to reach the necessary higher beam intensities and the associated beam diagnostics.

Seidl, P.A.; Anders, A.; Bieniosek, F.M.; Barnard, J.J.; Calanog, J.; Chen, A.X.; Cohen, R.H.; Coleman, J.E.; Dorf, M.; Gilson, E.P.; Grote, D.P.; Jung, J.Y.; Leitner, M.; Lidia, S.M.; Logan, B.G.; Ni, P.; Roy, P.K.; Van den Bogert, K.; Waldron, W.L.; Welch, D.R.

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

High brilliance negative ion and neutral beam source  

DOE Patents (OSTI)

A high brilliance mass selected (Z-selected) negative ion and neutral beam source having good energy resolution. The source is based upon laser resonance ionization of atoms or molecules in a small gaseous medium followed by charge exchange through an alkali oven. The source is capable of producing microampere beams of an extremely wide variety of negative ions, and milliampere beams when operated in the pulsed mode.

Compton, R.N.

1990-01-03T23:59:59.000Z

82

Propagation of ion beams through a tenuous magnetized plasma  

SciTech Connect

When an ion beam is propagated through a plasma, the question of charge neutralization is critical to its propagation. We consider such a problem where the plasma is magnetized with magnetic field perpendicular to the beam. The plasma-number density and beam-number density are assumed comparable. We reduce the problem to a two-dimensional model, which we solve. The solution suggests that it should be possible to attain charge neutralization if the beam density is properly varied along itself.

Chrien, E.F.; Valeo, E.J.; Kulsrud, R.M.; Oberman, C.R.

1985-10-01T23:59:59.000Z

83

Collective ion accelerator with foil-less beam extraction window  

SciTech Connect

Ions are generated in a vacuum condition of an ion accelerator and injected, through three aerodynamic windows, to atmospheric pressure. A coil provides a magnetic field to prevent the ion beam from dissipating while it is traveling through the windows to the atmosphere.

Roberts, T.G.

1978-10-17T23:59:59.000Z

84

Ion beam collimating grid to reduce added defects  

DOE Patents (OSTI)

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.

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

2003-01-01T23:59:59.000Z

85

Laser Ion Acceleration Toward Future Ion Beam Cancer Therapy - Numerical Simulation Sudy-  

E-Print Network (OSTI)

Ion beam has been used in cancer treatment, and has a unique preferable feature to deposit its main energy inside a human body so that cancer cell could be killed by the ion beam. However, conventional ion accelerator tends to be huge in its size and its cost. In this paper a future intense-laser ion accelerator is proposed to make the ion accelerator compact. An intense femtosecond pulsed laser was employed to accelerate ions. The issues in the laser ion accelerator include the energy efficiency from the laser to the ions, the ion beam collimation, the ion energy spectrum control, the ion beam bunching and the ion particle energy control. In the study particle computer simulations were performed to solve the issues, and each component was designed to control the ion beam quality. When an intense laser illuminates a target, electrons in the target are accelerated and leave from the target; temporarily a strong electric field is formed between the high-energy electrons and the target ions, and the target ions ...

Kawata, Shigeo; Nagashima, Toshihiro; Takano, Masahiro; Barada, Daisuke; Kong, Qing; Gu, Yan Jun; Wang, Ping Xiao; Ma, Yan Yun; Wang, Wei Ming

2013-01-01T23:59:59.000Z

86

A Novel Method for Fundamental Interaction Studies with Electrostatic Ion Beam Trap  

E-Print Network (OSTI)

Trapped radioactive atoms present exciting opportunities for the study of fundamental interactions and symmetries. For example, detecting beta decay in a trap can probe the minute experimental signal that originates from possible tensor or scalar terms in the weak interaction. Such scalar or tensor terms affect, e.g., the angular correlation between a neutrino and an electron in the beta-decay process, thus probing new physics of "beyond-the-standard-model" nature. In particular, this article focuses on a novel use of an innovative ion trapping device, the Electrostatic Ion Beam Trap (EIBT). Such a trap has not been previously considered for Fundamental Interaction studies and exhibits potentially very significant advantages over other schemes. These advantages include improved injection efficiency of the radionuclide under study, an extended field-free region, ion-beam kinematics for better efficiency and ease-of-operation and the potential for a much larger solid angle for the electron and recoiling atom counters.

S. Vaintraub; M. Hass; O. Aviv; O. Heber; I. Mardor

2010-05-22T23:59:59.000Z

87

Cyclotron axial ion-beam-buncher system  

DOE Patents (OSTI)

Adiabatic ion bunching is achieved in a cyclotron axial ion injection system through the incorporation of a radio frequency quadrupole system, which receives ions from an external ion source via an accelerate-decelerate system and a focusing einzel lens system, and which adiabatically bunches and then injects the ions into the median plane of a cyclotron via an electrostatic quadrupole system and an inflection mirror.

Hamm, R.W.; Swenson, D.A.; Wangler, T.P.

1982-02-11T23:59:59.000Z

88

Mini RF-driven ion source for focused ion beam system  

DOE Green Energy (OSTI)

Mini RF-driven ion sources with 1.2 cm and 1.5 cm inner chamber diameter have been developed at Lawrence Berkeley National Laboratory. Several gas species have been tested including argon, krypton and hydrogen. These mini ion sources operate in inductively coupled mode and are capable of generating high current density ion beams at tens of watts. Since the plasma potential is relatively low in the plasma chamber, these mini ion sources can function reliably without any perceptible sputtering damage. The mini RF-driven ion sources will be combined with electrostatic focusing columns, and are capable of producing nano focused ion beams for micro machining and semiconductor fabrications.

Jiang, X.; Ji, Q.; Chang, A.; Leung, K.N.

2002-08-02T23:59:59.000Z

89

Etching of Graphene Devices with a Helium Ion Beam  

E-Print Network (OSTI)

IM microscope image in Figure 2a, was He ion etched by sequen- tial imaging in high resolution. The grapheneEtching of Graphene Devices with a Helium Ion Beam Max C. Lemme, David C. Bell,,§ James R. Williams as for pos- sible nanoelectronics applications.1 3 Many experiments in the field are targeted at graphene

Lukin, Mikhail

90

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

E-Print Network (OSTI)

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

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

2011-07-12T23:59:59.000Z

91

Suppression of Beam-Ion Instability in Electron Rings with Multi-Bunch Train Beam Fillings  

SciTech Connect

The ion-caused beam instability in the future light sources and electron damping rings can be serious due to the high beam current and ultra-small emittance of picometer level. One simple and effective mitigation of the instability is a multi-bunch train beam filling pattern which can significantly reduce the ion density near the beam, and therefore reduce the instability growth rate up to two orders of magnitude. The suppression is more effective for high intensity beams with low emittance. The distribution and the field of trapped ions are benchmarked to validate the model used in the paper. The wake field of ion-cloud and the beam-ion instability is investigated both analytically and numerically. We derived a simple formula for the build-up of ion-cloud and instability growth rate with the multi-bunch-train filling pattern. The ion instabilities in ILC damping ring, SuperKEKB and SPEAR3 are used to compare with our analyses. The analyses in this paper agree well with simulations.

Wang, L.; Cai, Y.; Raubenheimer, T.O.; /SLAC; Fukuma, H.; /KEK, Tsukuba

2011-08-18T23:59:59.000Z

92

Analysis of a Cyclotron Based 400 MeV/u Driver System for a Radioactive Beam Facility  

E-Print Network (OSTI)

The creation of intense radioactive beams requires intense and energetic primary beams. A task force analysis of this subject recommended an acceleration system capable of 400 MeV/u uranium at 1 particle uA as an appropriate driver for such a facility. The driver system should be capable of accelerating lighter ions at higher intensity such that a constant final beam power (~100kW) is maintained. This document is a more detailed follow on to the previous analysis of such a system incorporating a cyclotron. The proposed driver pre-acceleration system consists of an ion source, radio frequency quadrupole, and linac chain capable of producing a final energy of 30 MeV/u and a charge (Q) to mass (A) of Q/A ~1/3. This acceleration system would be followed by a Separated Sector Cyclotron with a final output energy of 400 MeV/u. This system provides a more cost-effective solution in terms of initial capital investment as well as of operation compared to a fully linac system with the same primary beam output parameters.

F. Marti; R. C. York; H. Blosser; M. M. Gordon; D. Gorelov; T. Grimm; D. Johnson; P. Miller; E. Pozdeyev; J. Vincent; X. Wu; A. Zeller

1999-08-20T23:59:59.000Z

93

Ohmic heated sheet for the Ca ion beam production  

SciTech Connect

The production of intense accelerated {sup 48}Ca ion beams is the key problem in the experiments on the synthesis of new superheavy nuclei. For this purpose in the FLNR (JINR), an electron cyclotron resonance ion source is used at the U-400 cyclotron. The combination of a micro oven with a hot tantalum sheet inside the discharge chamber allowed the production of the intense {sup 48}Ca{sup 5+} ion beam at the {sup 48}Ca consumption of about 0.5 mg/h. In this case, the tantalum sheet is heated by microwaves and plasma electrons. The microwave power of up to 500 W is required to heat the sheet to the temperature of about 500 deg. C. To decrease the required microwave power, a new sheet with a direct Ohmic heating was designed. The present paper describes the method, technique, and preliminary experimental results on the production of the Ca ion beam.

Efremov, A.; Bogomolov, S.; Kazarinov, N.; Kochagov, O.; Loginov, V. [Joint Institute for Nuclear Research, Dubna, Moscow 141980 (Russian Federation)

2008-02-15T23:59:59.000Z

94

Negative Decaborane Ion Beam from ITEP Bernas Ion Source  

SciTech Connect

A joint research and development effort focusing on the design of steady state, intense ion sources has been in progress for the past two and a half years with a couple of Russian institutions. The ultimate goal of the effort is to meet the two, energy extreme range needs of mega-electron-volt and 100's of electron-volt ion implanters. This endeavor has already resulted in record steady state output currents of higher charge state antimony and phosphorous ions to meet high-energy implantation requirements. For low energy ion implantation, R and D efforts have involved molecular ions and a novel plasmaless/gasless deceleration method. To date, 1 emA of positive decaborane ions were extracted at 10 keV and a smaller current of negative decaborane ions were also extracted. Though of scientific interest, negative decaborane ions did not attract interest from industry, since the semiconductor ion implant industry seems to have solved the wafer-charging problem. This paper describes conditions under which negative decaborane ions are formed and extracted from a Bernas ion source.

Petrenko, S. V.; Kuibeda, R. P.; Kulevoy, T. V.; Batalin, V. A.; Pershin, V. I.; Koslov, A. V.; Stasevich, Yu. B.; Koshelev, V. A. [Institute for Theoretical and Experimental Physics, Moscow, (Russian Federation); Hershcovitch, A.; Johnson, B. M. [Brookhaven National Laboratory, Upton, New York 11973 (United States); Oks, E. M.; Gushenets, V. I. [High Current Electronics Institute Russian Academy of Sciences, Tomsk, 634055 (Russian Federation); Poole, H. J. [PVI, Oxnard, California 93031-5023 (United States)

2007-08-10T23:59:59.000Z

95

Anti-hydrogen production with positron beam ion trap  

Science Conference Proceedings (OSTI)

In low-energy antiproton physics, it is advantageous to be able to manipulate anti-particles as freely as normal particles. A robust production and storage system for high-quality positrons and antiprotons would be a substantial advance for the development of anti-matter science. The idea of electron beam ion trap could be applied for storage of anti-particle when the electron beam could be replaced by the positron beam. The bright positron beam would be brought about using synchrotron radiation source with a superconducting wiggler. The new scheme for production of anti-particles is proposed by using new accelerator technologies.

Itahashi, Takahisa [Department of Physics, Graduate School of Science, Osaka University 1-1 Machikaneyama, Toyonaka, Osaka 560-0043 (Japan)

2008-08-08T23:59:59.000Z

96

Initial commissioning results with the NSCL Electron Beam Ion Trap  

Science Conference Proceedings (OSTI)

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.

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

2012-02-15T23:59:59.000Z

97

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

SciTech Connect

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

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

2012-07-15T23:59:59.000Z

98

Beam instrumentation for the BNL Heavy Ion Transfer Line  

Science Conference Proceedings (OSTI)

The Heavy Ion Transfer Line (HITL) was constructed to transport beams from the BNL Tandem Van de Graaff (TVDG) to be injected into the AGS. Because the beam line is approximately 2000 feet long and the particle rigidity is so low, 20 beam monitor boxes were placed along the line. The intensity ranges from 1 to 100 nanoAmps for the dc trace beam used for line set-up, to over 100 ..mu..A for the pulsed beam to be injected into the AGS. Profiles are measured using multiwire arrays (HARPS) while Faraday cups and beam transformers monitor the intensity. The electronics stations are operated through 3 Instrumentation Controllers networked to Apollo workstations in the TVDG and AGS control rooms. Details of the detectors and electronics designs and performance will be given.

Witkover, R.L.; Buxton, W.; Castillo, V.; Feigenbaum, I.; Lazos, A.; Li, Z.G.; Smith, G.; Stoehr, R.

1987-01-01T23:59:59.000Z

99

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

DOE Patents (OSTI)

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.

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

1993-03-30T23:59:59.000Z

100

Improved production of N{sup +} ions from a multicusp ion beam apparatus  

DOE Patents (OSTI)

This invention is comprised of 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 beam, 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 +} 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.

Leung, Ka-Ngo; Kunkel, W.B.; Walther, S.R.

1991-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

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

DOE Patents (OSTI)

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.

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

1993-01-01T23:59:59.000Z

102

Inertial Fusion Driven by Intense Heavy-Ion Beams  

NLE Websites -- All DOE Office Websites (Extended Search)

INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMS INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMS * W. M. Sharp # , A. Friedman, D. P. Grote, J. J. Barnard, R. H. Cohen, M. A. Dorf, S. M. Lund, L. J. Perkins, M. R. Terry, LLNL, Livermore, CA, USA B. G. Logan, F. M. Bieniosek, A. Faltens, E. Henestroza, J.-Y. Jung, J. W. Kwan, E. P. Lee, S. M. Lidia, P. A. Ni, L. L. Reginato, P. K. Roy, P. A. Seidl, J. H. Takakuwa, J.-L. Vay, W. L. Waldron, LBNL, Berkeley, CA, USA R. C. Davidson, E. P. Gilson, I. D. Kaganovich, H. Qin, E. Startsev, PPPL, Princeton, NJ, USA I. Haber, R. A. Kishek, University of Maryland, College Park, MD, USA A. E. Koniges, NERSC, Berkeley, CA, USA Abstract Intense heavy-ion beams have long been considered a promising driver option for inertial-fusion energy production. This paper briefly compares inertial

103

Electrostatic lens to focus an ion beam to uniform density  

SciTech Connect

A focusing lens for an ion beam having a gaussian or similar density profile is provided. The lens is constructed to provide an inner zero electrostatic field, and an outer electrostatic field such that ions entering this outer field are deflected by an amount that is a function of their distance from the edge of the inner field. The result is a beam that focuses to a uniform density in a manner analogous to that of an optical ring lens. In one embodiment, a conically-shaped network of fine wires is enclosed within a cylindrical anode. The wire net together with the anode produces a voltage field that re-directs the outer particles of the beam while the axial particles pass undeflected through a zero field inside the wire net. The result is a focused beam having a uniform intensity over a given target area and at a given distance from the lens.

Johnson, Cleland H. (Oak Ridge, TN)

1977-01-11T23:59:59.000Z

104

Deposition and surface treatment with intense pulsed ion beams  

Science Conference Proceedings (OSTI)

Intense pulsed ion beams (500 keV, 30 kA, 0.5 {mu}s) are being investigated for materials processing. Demonstrated and potential applications include film deposition, glazing and joining, alloying and mixing, cleaning and polishing, corrosion improvement, polymer surface treatments, and nanophase powder synthesis. Initial experiments at Los Alamos have emphasized thin-film formation by depositing beam ablated target material on substrates. We have deposited films with complex stoichiometry such as YBa{sub 2}Cu{sub 3}O{sub 7-x}, and formed diamond-like-carbon films. Instantaneous deposition rates of 1 mm/sec have been achieved because of the short ion range (typically 1{mu}m), excellent target coupling, and the inherently high energy of these beams. Currently the beams are produced in single shot uncomplicated diodes with good electrical efficiency. High-voltage modulator technology and diodes capable of repetitive firing, needed for commercial application, are being developed.

Olson, J.C.; Davis, H.A.; Rej, D.J.; Waganaar, W.J. [Los Alamos National Lab., NM (United States); Stinnett, R.W.; McIntyre, D.C. [Sandia National Labs., Albuquerque, NM (United States)

1995-02-08T23:59:59.000Z

105

Images of Complex Interactions of an Intense Ion Beam with Plasma Electrons  

SciTech Connect

Ion beam propagation in a background plasma is an important scientific issue for many practical applications. The process of ion beam charge and current neutralization is complex because plasma electrons move in strong electric and magnetic fields of the beam. Computer simulation images of plasma interaction with an intense ion beam pulse are presented.

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

2004-08-03T23:59:59.000Z

106

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

SciTech Connect

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

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

2005-02-28T23:59:59.000Z

107

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

DOE Patents (OSTI)

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.

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

2011-03-08T23:59:59.000Z

108

Novel materials synthesis using an intense pulsed ion beam  

Science Conference Proceedings (OSTI)

Initial experiments on evaporation from metallic and ceramic targets using a pulsed light ion beam source is reported. The source is an intense ion beam produced by a 1.2 MV, 300 kJ Anaconda generator fitted with an extraction diode. Beam fluences of 10--20 J/cm{sup 2} gives a deposition rate of about 30--50 nm per shot, for both brass and YBa{sub 2}Cu{sub 3}O{sub 7-x} (1-2-3) targets. This is about 1000 times greater than comparable rates from pulsed laser deposition (PLD). Single-shot ablated 1-2-3 films, deposited on Si, were analyzed using RBS; the measured stoichiometry was close to 1-2-3 in favorable cases, but shot-to-shot reproducibility was poor. Approximately 1% of the available ion beam energy was utilized for these initial experiments. The potential for producing large area coatings from multi-cation targets and nanophase powders using pulsed ion beam deposition will be discussed.

Gautier, D.C.; Muenchausen, R.E.; Rej, D.J.; Roberts, B.F.; Waganarr, W.J. [Los Alamos National Lab., NM (United States); Johnston, G. [New Mexico Univ., Albuquerque, NM (United States)

1992-12-31T23:59:59.000Z

109

Novel materials synthesis using an intense pulsed ion beam  

Science Conference Proceedings (OSTI)

Initial experiments on evaporation from metallic and ceramic targets using a pulsed light ion beam source is reported. The source is an intense ion beam produced by a 1.2 MV, 300 kJ Anaconda generator fitted with an extraction diode. Beam fluences of 10--20 J/cm[sup 2] gives a deposition rate of about 30--50 nm per shot, for both brass and YBa[sub 2]Cu[sub 3]O[sub 7-x] (1-2-3) targets. This is about 1000 times greater than comparable rates from pulsed laser deposition (PLD). Single-shot ablated 1-2-3 films, deposited on Si, were analyzed using RBS; the measured stoichiometry was close to 1-2-3 in favorable cases, but shot-to-shot reproducibility was poor. Approximately 1% of the available ion beam energy was utilized for these initial experiments. The potential for producing large area coatings from multi-cation targets and nanophase powders using pulsed ion beam deposition will be discussed.

Gautier, D.C.; Muenchausen, R.E.; Rej, D.J.; Roberts, B.F.; Waganarr, W.J. (Los Alamos National Lab., NM (United States)); Johnston, G. (New Mexico Univ., Albuquerque, NM (United States))

1992-01-01T23:59:59.000Z

110

Broad-beam multi-ampere metal ion source  

SciTech Connect

An embodiment of the MEVVA (metal vapor vacuum arc) high current metal ion source has been developed in which the beam is formed from a 10-cm diameter set of extractor grids and which produces a peak beam current of up to several Amperes. The source, MEVVA V, operates in a pulsed mode with a pulse width at present 0.25 ms and a repetition rate of up to several tens of pulses per second (power supply limited). The multicathode feature that was developed for the prior source version, MEVVA IV, has been incorporated here also; one can switch between any of 18 separate cathodes and thus metallic beam species. Maximum beam extraction voltage is over 90 kV, and since the ion charge state typically from Q = 1 to 5, depending on the metal employed, the ion energy in the extracted beam can thus be up to several hundred keV. This source is a new addition to the MEVVA family of metal ion sources, and we are at present investigating the operational regimes and the limits to the source performance. In this paper we describe the source and present some preliminary results. 10 refs., 4 figs.

Brown, I.G.; Galvin, J.E.; MacGill, R.A.; Paoloni, F.J. (Lawrence Berkeley Lab., CA (USA); Wollongong Univ. (Australia). Dept. of Electrical Engineering)

1989-06-01T23:59:59.000Z

111

Fast fall-time ion beam in neutron generators  

Science Conference Proceedings (OSTI)

Ion beam with a fast fall time is useful in building neutron generators for the application of detecting hidden, gamma-shielded SNM using differential die-away (DDA) technique. Typically a fall time of less than 1 {micro}s can't be achieved by just turning off the power to the ion source due to the slow decay of plasma density (partly determined by the fall time of the RF power in the circuit). In this paper, we discuss the method of using an array of mini-apertures (instead of one large aperture beam) such that gating the beamlets can be done with low voltage and a small gap. This geometry minimizes the problem of voltage breakdown as well as reducing the time of flight to produce fast gating. We have designed and fabricated an array of 16 apertures (4 x 4) for a beam extraction experiment. Using a gating voltage of 1400 V and a gap distance of 1 mm, the fall time of extracted ion beam pulses is less than 1 {micro}s at various beam energies ranging between 400 eV to 800 eV. Usually merging an array of beamlets suffers the loss of beam brightness, i.e., emittance growth, but that is not an important issue for neutron source applications.

Ji, Q.; Kwan, J.; Regis, M.; Wu, Y.; Wilde, S.B.; Wallig, J.

2008-08-10T23:59:59.000Z

112

Means for obtaining a metal ion beam from a heavy-ion cyclotron source  

DOE Patents (OSTI)

A description is given of a modification to a cyclotron ion source used in producing a high intensity metal ion beam. A small amount of an inert support gas maintains the usual plasma arc, except that it is necessary for the support gas to have a heavy mass, e.g., xenon or krypton as opposed to neon. A plate, fabricated from the metal (or anything that can be sputtered) to be ionized, is mounted on the back wall of the ion source arc chamber and is bombarded by returning energetic low-charged gas ions that fail to cross the initial accelerating gap between the ion source and the accelerating electrode. Some of the atoms that are dislodged from the plate by the returning gas ions become ionized and are extracted as a useful beam of heavy ions. (auth)

Hudson, E.D.; Mallory, M.L.

1975-08-01T23:59:59.000Z

113

Ion beam surface treatment: A new capability for surface enhancement  

Science Conference Proceedings (OSTI)

The emerging capability to produce high average power (5--350 kW) pulsed ion beams at 0.2--2 MeV energies is enabling the authors to develop a new, commercial-scale thermal surface treatment technology called Ion Beam Surface Treatment (IBEST). This new technique uses high energy, pulsed ({<=}250 ns) ion beams to directly deposit energy in the top 2--20 micrometers of the surface of any material. The depth of treatment is controllable by varying the ion energy and species. Deposition of the energy with short pulses in a thin surface layer allows melting of the layer with relatively small energies and allows rapid cooling of the melted layer by thermal diffusion into the underlying substrate. Typical cooling rates of this process (10{sup 9}--10{sup 10} K/sec) cause rapid resolidification, resulting in the production of non-equilibrium microstructures (nano-crystalline and metastable phases) that have significantly improved corrosion, wear, and hardness properties. The authors conducted IBEST feasibility experiments with results confirming surface hardening, noncrystalline grain formation, metal surface polishing, controlled melt of ceramic surfaces, and surface cleaning using pulsed ion beams.

Stinnett, R.W.; McIntyre, D.C.; Buchheit, R.G.; Neau, E.L. [Sandia National Labs., Albuquerque, NM (United States); Greenly, J.B.; Thompson, M.O. [Cornell Univ., Ithaca, NY (United States); Johnston, G.P. [Univ. of New Mexico, Albuquerque, NM (United States); Rej, D.J. [Los Alamos National Lab., NM (United States)

1994-07-01T23:59:59.000Z

114

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

SciTech Connect

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

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

2005-09-01T23:59:59.000Z

115

Ion beam characterization of multi-layer dielectric reflectors  

Science Conference Proceedings (OSTI)

Energetic ion beams were used to characterize multilayer dielectric reflectors. Alpha-particle beams with beam spot sizes between 10 microns and a few millimeters were scattered from reflectors consisting of 32-layer SiO/sub 2//HfO/sub 2/ and 38-layer MgF/sub 2//ThF/sub 4/. The RBS spectra reveal the nature of the laser damage processes by providing information on diffusion, mixing, and loss of material in the coatings. The particle-induced x-ray emission (PIXE) technique gave complimentary results on low-concentration impurities in the coatings.

Beery, J.G.; Hollander, M.G.; Maggiore, C.J.; Redondo, A.; Westervelt, R.T.; Taylor, T.N.

1985-01-01T23:59:59.000Z

116

Simulation study of beam-beam effects in ion beams with large space charge tuneshift  

Science Conference Proceedings (OSTI)

During low-energy operations with gold-gold collisions at 3.85 GeV beam energy, significant beam lifetime reductions have been observed due to the beam-beam interaction in the presence of large space charge tuneshifts. These beam-beam tuneshift parameters were about an order of magnitude smaller than during regular high energy operations. To get a better understanding of this effect, simulations have been performed. Recent results are presented.

Montag C.

2012-05-20T23:59:59.000Z

117

Risk Management Plan Electron Beam Ion Source Project  

E-Print Network (OSTI)

. The estimated costs and contingencies to mitigate these risks are incorporated in the Project baseline costRisk Management Plan for the Electron Beam Ion Source Project (EBIS) Project # 06-SC-002 of Nuclear Physics (SC ­ 26) #12;1. Background and References 1.1 Background The EBIS Project will manage

Homes, Christopher C.

118

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

SciTech Connect

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.

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

2007-08-10T23:59:59.000Z

119

Thermal imaging experiments on ANACONDA ion beam generator  

Science Conference Proceedings (OSTI)

The thermal imaging technique was used in two experimental measurements. First, the ion intensity distribution on the anode surface was observed from different angles by using a multi-pinhole camera. Second, the plume from a target intercepting the beam was visualized by observing the distribution of temperature increase on a thin plate hit by the plume.

Jiang, W.; Yatsui, K. [Nagaoka Univ. of Technology (Japan). Lab. of Beam Technology; Olson, J.C.; Davis, H.A. [Los Alamos National Lab., NM (United States)

1996-12-31T23:59:59.000Z

120

Ultrahigh vacuum focused ion beam micromill and articles therefrom  

DOE Patents (OSTI)

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.

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

1998-02-24T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Spatially resolved instability measurements with a heavy ion beam probe  

SciTech Connect

A heavy ion beam probe was used to make simultaneous measurements of the amplitude and phase of both density and space potential fluctuations in an energetic arc plasma. Detailed comparison with theoretical predictions identifies a 70 KHz coherent oscillation as a Kelvin-Helmholtz instability localized to a region of strong fluid shear. (auth)

Jennings, W. C.; Hickok, R. L.; Glowienka, J. C.

1975-01-01T23:59:59.000Z

122

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

SciTech Connect

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.

Knapp, D.

1994-11-02T23:59:59.000Z

123

Develpoment of a one-meter plasma source for heavy ion beam charge neutralization  

E-Print Network (OSTI)

Heavy Ion Beam Driven Fusion Reactor Study”, KfK-3480,is a possible heavy ion fusion reactor design [1]. The final

2005-01-01T23:59:59.000Z

124

Excitation of electrostatic ion-cyclotron waves by an ion beam in a two-ion component plasma  

SciTech Connect

An ion beam propagating through a magnetized plasma cylinder containing electrons, light positive potassium ions (K{sup +}), and heavy positive cesium ions (Cs{sup +}) drives electrostatic ion cyclotron (EIC) waves to instability via Cerenkov interaction. Two EIC wave modes are present, the K{sup +} and Cs{sup +} modes. The unstable wave frequencies and the growth rate of both the light positive ion and heavy positive ion modes increase with an increase in their relative ion concentrations. The growth rate of both the unstable modes (K{sup +} and Cs{sup +}) scales one-third power of the beam density. The real part of the frequency of both the unstable modes (K{sup +} and Cs{sup +}) increases with the beam energy and scales as almost one-half power of the beam energy. Numerical calculations of the growth rate and mode frequencies have been carried out for the parameters of the experiment of Suszcynsky et al. [J. Geophys. Res. 94, 8966 (1989)]. It is found that the unstable wave frequencies of both the light positive ion and heavy positive ion modes increase with the magnetic fields in accordance with the experimental observations.

Sharma, Jyotsna [Department of Physics, KIIT College of Engineering, Bhondsi Gurgaon 122102 (India); Sharma, Suresh C. [Department of Physics, Maharaja Agrasen Institute of Technology, PSP Area Plot No.-1, Sector-22, Rohini, Delhi 110086 (India)

2010-12-15T23:59:59.000Z

125

Electrostatic dispersion lenses and ion beam dispersion methods  

DOE Patents (OSTI)

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.

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

2010-12-28T23:59:59.000Z

126

3D Elemental Mapping of Cells using Electron and Ion Beams  

Science Conference Proceedings (OSTI)

3D Elemental Mapping of Cells Using Electron and Ion Beams. Summary: Although it is the most commonly used technique ...

2012-10-02T23:59:59.000Z

127

Fast ion behavior during neutral beam injection in ATF  

SciTech Connect

In stellarators, single-particle confinement properties can be more complex than in their tokamak counterparts. Fast-ion behavior in tokamaks has been well characterized through an abundance of measurements on various devices and in general has been shown to be consistent with classical slowing-down theory, although anomalous ion behavior has been observed during intense beam injection in ISX-B, during fishbone instabilities in PDX, and in experiments on TFR. In contrast, fast ion behavior in stellarators is not as wel established experimentally with the primary experiments to date focusing o near-perpendicular or perpendicular neutral beam injection (NBI) on the Wendelstein 7-A stellarator (91 and Heliotron-E. This paper addresses fast-ion confinement properties in a large-aspect-ratio, moderate-shear stellarator, the Advanced Toroidal Facility, during tangential NBI. The primary data used in this study are the experimentally measured energy spectra of charge-exchange neutrals escaping from the plasma, using a two-dimensional scanning neutral particle analyzer. This diagnostic method is well established, having been used on several devices since the early 1970`s. Various aspects of fast-ion behavior are investigated by comparing these data with computed theoretical spectra based on energeticion distributions derived from the fastion Fokker-Planck equation. Ion orbits are studied by computer orbit following, by the computation of J* surfaces, and by Monte Carlo calculations.

Wade, M.R.; Thomas, C.E.; Colchin, R.J.; Rome, J.A.; England, A.C.; Fowler, R.H. [Oak Ridge National Lab., TN (United States); Aceto, S.C. [Rensselaer Polytechnic Inst., Troy, NY (United States)

1993-09-01T23:59:59.000Z

128

Method for measuring and controlling beam current in ion beam processing  

DOE Patents (OSTI)

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.

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

2003-04-29T23:59:59.000Z

129

Stroboscopic Laser Diagnostics for Detection of Ordering in One-Dimensional Ion beam.  

E-Print Network (OSTI)

A novel diagnostic method for detecting ordering in one-dimensional ion beams is presented. The ions are excited by a pulsed laser at two different positions along the beam and fluorescence is observed by a group of four photomultipliers. Correlation in fluorescence signals is firm indication that the ion beam has an ordered structure.

unknown authors

2008-01-01T23:59:59.000Z

130

Substrate heating measurements in pulsed ion beam film deposition  

Science Conference Proceedings (OSTI)

Diamond-like Carbon (DLC) films have been deposited at Los Alamos National Laboratory by pulsed ion beam ablation of graphite targets. The targets were illuminated by an intense beam of hydrogen, carbon, and oxygen ions at a fluence of 15-45 J/cm{sup 2}. Ion energies were on the order of 350 keV, with beam current rising to 35 kA over a 400 ns ion current pulse. Raman spectra of the deposited films indicate an increasing ratio of sp{sup 3} to sp{sup 2} bonding as the substrate is moved further away from the target and further off the target normal. Using a thin film platinum resistor at varying positions, we have measured the heating of the substrate surface due to the kinetic energy and heat of condensation of the ablated material. This information is used to determine if substrate heating is responsible for the lack of DLC in positions close to the target and near the target normal. Latest data and analysis will be presented.

Olson, J.C.; Davis, H.A.; Rej, D.J.; Waganaar, W.J. [Los Alamos National Lab., NM (United States); Tallant, D.R. [Cornell Univ., Ithaca, NY (United States). Materials Science and Engineering Dept.; Thompson, M.O. [Sandia National Labs., Albuquerque, NM (United States)

1995-05-01T23:59:59.000Z

131

Low energy ion beam assisted deposition of a spin valve  

Science Conference Proceedings (OSTI)

The spin dependent electron transport in giant magnetoresistive (GMR) multilayers is significantly affected by the atomic scale structure of their interfaces. Devices with atomically flat and chemically sharp interfaces are preferred for magnetic sensor and memory applications. Recent atomic simulations of the atom-by-atom assembly of these devices indicate that near optimal interfacial structures can be created using low energy, ion assisted vapor deposition techniques with ion energies in the 5-10 eV range. A recently developed biased target ion beam deposition system has been used to experimentally test this hypothesis. Prototypical Ta/NiFe/Co/Cu/Co/FeMn/Cu spin valve structures were first grown using (simultaneous) argon ion assistance during deposition of the Co/Cu/Co trilayer part of the spin valve multilayer. Assisting ion energies of around 10 eV resulted in structures with a 30% higher magnetoresistance ratio and significantly reduced coupling field compared to samples grown with no ion assistance or with ion energies above 15 eV. These results are consistent with the atomistic simulation predictions. Other promising ion assistance schemes identified by the simulations were then used to deposit the Ta, NiFe, FeMn, and the top copper layer. A near optimal strategy was identified that resulted in the further improvement of the GMR ratio.

Quan, J. J.; Wolf, S. A.; Wadley, H. N. G. [Department of Materials Science and Engineering, School of Engineering and Applied Science, University of Virginia, Charlottesville, Virginia 22903 (United States)

2007-04-01T23:59:59.000Z

132

Neutron Transfer Studied with a Radioactive beam of 24Ne, using TIARA at SPIRAL  

E-Print Network (OSTI)

A general experimental technique for high resolution studies of nucleon transfer reactions using radioactive beams is briefly described, together with the first new physics results that have been obtained with the new TIARA array. These first results from TIARA are for the reaction 24Ne(d,p)25Ne, studied in inverse kinematics with a pure radioactive beam of 100,000 pps from the SPIRAL facility at GANIL. The reaction probes the energies of neutron orbitals relevant to very neutron rich nuclei in this mass region and the results highlight the emergence of the N=16 magic number for neutrons and the associated disappearance of the N=20 neutron magic number for the very neutron rich neon isotopes.

W. N. Catford; C. N. Timis; R. C. Lemmon; M. Labiche; N. A. Orr; L. Caballero; R. Chapman; M. Chartier; M. Rejmund; H. Savajols; for the TIARA Collaboration

2009-12-20T23:59:59.000Z

133

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

DOE Patents (OSTI)

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.

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

2012-10-30T23:59:59.000Z

134

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

Magee, Joseph W.

135

Self?aligned high electron mobility transistor gate fabrication using focused ion beams  

Science Conference Proceedings (OSTI)

A new gate fabrication technique has been developed based on focused ion beam exposure and reactive ion etching of a polymethylmethacrylate (PMMA)/Ge/PMMA multilevel resist structure. The focused ion beam exposes the thin PMMA imaging layer that is transferred directly to the germanium layer using reactive ion etching (RIE). The underlying resist is etched first in oxygen at high pressure

G. M. Atkinson; R. L. Kubena; L. E. Larson; L. D. Nguyen; F. P. Stratton; L. M. Jelloian; M. V. Le; H. McNulty

1991-01-01T23:59:59.000Z

136

PARALLEL ION BEAM PROFILE SCAN USING LASER WIRE  

Science Conference Proceedings (OSTI)

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

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

2013-01-01T23:59:59.000Z

137

Ion-exchange material and method of storing radioactive wastes  

DOE Patents (OSTI)

A new cation exchanger is a modified tobermorite containing aluminum isomorphously substituted for silicon and containing sodium or potassium. The exchanger is selective for lead, rubidium, cobalt, and cadmium and is selective for cesium over calcium or sodium. The tobermorites are compatible with cement and are useful for the long-term fixation and storage of radioactive nuclear wastes.

Komarneni, S.; Roy, D.M.

1983-10-31T23:59:59.000Z

138

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

SciTech Connect

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

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

2012-02-20T23:59:59.000Z

139

Reduction of Glass Surface Reflectance by Ion Beam Surface Modification  

DOE Green Energy (OSTI)

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.

Mark Spitzer

2011-03-11T23:59:59.000Z

140

Beam Purification by Photodetachment  

Science Conference Proceedings (OSTI)

Ion beam purity is of crucial importance to many basic and applied studies. Selective photodetachment has been proposed to suppress unwanted species in negative ion beams while preserving the intensity of the species of interest. A highly efficient technique based on photodetachment in a gas-filled radio frequency quadrupole ion cooler has been demonstrated. In off-line experiments with stable ions, up to 104 times suppression of the isobar contaminants in a number of interesting radioactive negative ion beams has been demonstrated. For selected species, this technique promises experimental possibilities in studies on exotic nuclei, accelerator mass spectrometry, and fundamental properties of negative atomic and molecular ions.

Liu, Yuan [ORNL; Beene, James R [ORNL; Havener, Charles C [ORNL; Galindo-Uribarri, Alfredo {nmn} [ORNL; Andersson, P. [University of Gothenburg, Sweden; Lindahl, A. O. [University of Gothenburg, Sweden; Hanstorp, D. [University of Gothenburg, Sweden; Forstner, Dr. Oliver [University of Vienna, Austria; Gottwald, T. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Wendt, K. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

An ultra-low energy (30-200 eV) ion-atomic beam source for ion-beam-assisted deposition in ultrahigh vacuum  

SciTech Connect

The paper describes the design and construction of an ion-atomic beam source with an optimized generation of ions for ion-beam-assisted deposition under ultrahigh vacuum (UHV) conditions. The source combines an effusion cell and an electron impact ion source and produces ion beams with ultra-low energies in the range from 30 eV to 200 eV. Decreasing ion beam energy to hyperthermal values ({approx_equal}10{sup 1} eV) without loosing optimum ionization conditions has been mainly achieved by the incorporation of an ionization chamber with a grid transparent enough for electron and ion beams. In this way the energy and current density of nitrogen ion beams in the order of 10{sup 1} eV and 10{sup 1} nA/cm{sup 2}, respectively, have been achieved. The source is capable of growing ultrathin layers or nanostructures at ultra-low energies with a growth rate of several MLs/h. The ion-atomic beam source will be preferentially applied for the synthesis of GaN under UHV conditions.

Mach, Jindrich; Kolibal, Miroslav; Sikola, Tomas [Institute of Physical Engineering, Brno University of Technology, Technicka 2, 616 69 Brno (Czech Republic); CEITEC BUT, Brno University of Technology, Technicka 10, 61669 Brno (Czech Republic); Samoril, Tomas; Voborny, Stanislav; Zlamal, Jakub; Spousta, Jiri; Dittrichova, Libuse [Institute of Physical Engineering, Brno University of Technology, Technicka 2, 616 69 Brno (Czech Republic)

2011-08-15T23:59:59.000Z

142

Characteristics of low-energy ion beams extracted from a wire electrode geometry  

SciTech Connect

Beams of argon ions with energies less than 50 eV were extracted from an ion source through a wire electrode extractor geometry. A retarding potential energy analyzer (RPEA) was constructed in order to characterize the extracted ion beams. The single aperture RPEA was used to determine the ion energy distribution function, the mean ion energy and the ion beam energy spread. The multi-cusp hot cathode ion source was capable of producing a low electron temperature gas discharge to form quiescent plasmas from which ion beam energy as low as 5 eV was realized. At 50 V extraction potential and 0.1 A discharge current, the ion beam current density was around 0.37 mA/cm{sup 2} with an energy spread of 3.6 V or 6.5% of the mean ion energy. The maximum ion beam current density extracted from the source was 0.57 mA/cm{sup 2} for a 50 eV ion beam and 1.78 mA/cm{sup 2} for a 100 eV ion beam.

Vasquez, M. Jr.; Tokumura, S.; Kasuya, T. [Graduate School of Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321 (Japan); Maeno, S. [Novelion Systems Co. Ltd., Kyotanabe, Kyoto 610-0332 (Japan); Wada, M. [Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Kyoto 610-0321 (Japan)

2012-02-15T23:59:59.000Z

143

High resolution and high density ion beam lithography employing HSQ resist  

Science Conference Proceedings (OSTI)

In the early stages of focused ion beam (FIB) development, ion beam lithography (IBL) employing organic resists showed potential advantages over electron beam lithography (EBL) (most notably less proximity effects and higher sensitivity [1,2]). However, ... Keywords: FIB, HSQ, IBL, LMIS, Nano patterning, Resist

L. Bruchhaus; S. Bauerdick; L. Peto; U. Barth; A. Rudzinski; J. Mussmann; J. Klingfus; J. Gierak; H. HöVel

2012-09-01T23:59:59.000Z

144

A discussion on the application and production of metal ion beams  

SciTech Connect

Metal ion beams, which are used in surface modification of metals and alloys as ion beam micrometallurgy, are promising candidates for advanced applications in semiconductors and insulators. Doping with transition metal and rare-earth metal ions in semiconductors and insulators to form metallic nanoclusters attracted much more attention recently, since their applications in diluted magnetic semiconductors, electroluminescent devices, giant magnetic resistance, etc. In this paper, some experiments for metal ion beams will be presented, and various methods and technologies for the production of metal ion beams will be discussed.

Ren Xiaotang; Zhao Ziqiang; Zhao Weijiang [Institute of Heavy Ion Physics, Peking University, Beijing, 100871 (China) and Key Laboratory of Heavy Ion Physics (Peking University), Ministry of Education, Beijing 100871 (China)

2008-02-15T23:59:59.000Z

145

Focused ion beam induced structural modifications in thin magnetic films  

SciTech Connect

Focused ion beam techniques are one way to modify locally the properties of magnetic thin films. We report on structural investigations of 50 nm thick non-ordered nano-crystalline Permalloy (Ni{sub 81}Fe{sub 19}) films modified by 30 keV Ga{sup +} focused ion beam (FIB) irradiation. From the x-ray diffraction (XRD) measurements a considerable crystallite growth and a material texturing towards (111)-direction with a linearly increasing lattice constant was observed. In addition, cross-sectional transmission electron microscope (XTEM) images show that crystallites are growing through the entire film at high irradiation fluences. Extended x-ray absorption fine structure (EXAFS) analysis shows a perfect near-order coordination corresponding to a face-centered (fcc) unit cell for both Fe, Ni and Ga atom surrounding. The structural changes are accompanied by a decrease of saturation polarization with increasing ion fluence. Such a behavior is attributed to the incorporation of non-magnetic Ga atoms in the Permalloy film.

Roshchupkina, O. D.; Grenzer, J.; Strache, T.; McCord, J.; Fritzsche, M.; Muecklich, A.; Baehtz, C.; Fassbender, J. [Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Ion Beam Physics and Materials Research, Dresden (Germany)

2012-08-01T23:59:59.000Z

146

Ion optical design of a collinear laser-negative ion beam apparatus  

Science Conference Proceedings (OSTI)

An apparatus for photodetachment studies on atomic and molecular negative ions of medium up to heavy mass (M {approx_equal} 500) has been designed and constructed. Laser and ion beams are merged in the apparatus in a collinear geometry and atoms, neutral molecules and negative ions are detected in the forward direction. The ion optical design and the components used to optimize the mass resolution and the transmission through the extended field-free interaction region are described. A 90 deg. sector field magnet with 50 cm bending radius in combination with two slits is used for mass dispersion providing a resolution of M/{Delta}M congruent with 800 for molecular ions and M/{Delta}M congruent with 400 for atomic ions. The difference in mass resolution for atomic and molecular ions is attributed to different energy distributions of the sputtered ions. With 1 mm slits, transmission from the source through the interaction region to the final ion detector was determined to be about 0.14%.

Diehl, C.; Wendt, K. [Institut fuer Physik, Johannes Gutenberg-Universitaet, Mainz, D-55099 Mainz (Germany); Lindahl, A. O.; Andersson, P.; Hanstorp, D. [Department of Physics, University of Gothenburg, SE-412 96 Goeteborg (Sweden)

2011-05-15T23:59:59.000Z

147

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

DOE Patents (OSTI)

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

Hershcovitch, A.

1984-02-13T23:59:59.000Z

148

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

Science Conference Proceedings (OSTI)

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.

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

2012-10-15T23:59:59.000Z

149

Film deposition and surface modification using intense pulsed ion beams  

SciTech Connect

High-power pulsed ion beams have been used to ablate material for ultrahigh-rate film deposition and to treat the surfaces of alloys. Pulsed ion beams were provided by the high-power-density Gamble II facility at the Naval Research Laboratory [high voltage ({similar_to}900 keV), short pulse (60 ns)] and the lower-power-density Anaconda facility at Los Alamos National Laboratory [lower voltage ({similar_to}300 keV), longer pulse (400 ns)]. Peak film deposition rates after target ablation reached 1 mm/s. Films of pure Al, pure Ta, YBCO, and Ni--Zn ferrite were deposited on glass and single-crystal substrates, in some cases heated. The film deposition process was studied with framing photography, a bolometer, and other diagnostics to gain an understanding of the ablation, transport, and deposition steps. Stoichiometric deposition of multicomponent targets has been demonstrated. Film morphology remains poor, but has steadily improved, and our present understanding points the way to further improvement. Lower fluences ({similar_to}5 J/cm{sup 2}) were used to investigate rapid thermal processing of metal surfaces for the enhancement of corrosion resistance. The results in this area have been negative, but here again the knowledge gained through these experiments allows us to propose directions for improvement. {copyright} {ital 1995} {ital American} {ital Vacuum} {ital Society}

Meli, C.A.; Grabowski, K.S.; Hinshelwood, D.D.; Stephanakis, S.J. [Naval Research Laboratory, Washington, DC 20375 (United States)] [Naval Research Laboratory, Washington, DC 20375 (United States); Rej, D.J.; Waganaar, W.J. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

1995-05-01T23:59:59.000Z

150

Deposition of DLC via intense ion beam ablation  

Science Conference Proceedings (OSTI)

Diamond-like carbon films were prepared by high intensity pulsed ion beam ablation of graphite targets. A 350 key, 35 kA, 400 ns pulse width beam, consisting primarily of carbon ions and protons, was focused onto a graphite target at a fluence of 15-45J/cm{sup 2}. Films were deposited onto substrates positioned i.n q n angular array from normal to the target to 90{degrees} off normal. Deposition rates up to 30 nm per pulse, corresponding to an instantaneous deposition rate greater than I mn/sec, have been observed. Electrical resistivities between 1 and 1000 ohm-cm were measured for these films. XRD scans showed that no crystalline structure developed in the films. SEM revealed that the bulk of the films contain material with feature sizes on the order of 100 nm, but micron size particles were deposited as well. Both Raman and electron energy loss spectroscopy indicated significant amounts of sp{sup 3} bonded carbon present in most of the films.

Johnston, G.P. [Los Alamos National Lab., NM (United States)]|[Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Chemical Engineering; Tiwari, P.; Rej, D.J.; Davis, H.A.; Waganaar, W.J.; Muenchausen, R.E. [Los Alamos National Lab., NM (United States); Tallant, D.; Simpson, R.L. [Sandia National Lab., Albuquerque, NM (United States); Williams, D.B. [Lehigh Univ., Bethlehem, PA (United States). Dept. of Metallurgy and Materials Engineering; Qui, X. [Univ. of New Mexico, Albuquerque, NM (United States). Dept of Chemical Engineering

1993-12-31T23:59:59.000Z

151

Plasma and Beam Production Experiments with HYBRIS, a Microwave-assisted H- Ion  

E-Print Network (OSTI)

Beam Results Obtained with the SNS H- Ion Source and LEBT atgenerator and coupled to an SNS-type multi-cusp H - ionin the present version of the SNS ion source. Initial tests

Keller, R. AUTHOR-Kwan, S.; Hahto, S.; Regis, M.; Wallig, J.

2006-01-01T23:59:59.000Z

152

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

SciTech Connect

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.

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

2012-09-03T23:59:59.000Z

153

LIBRA-A light ion beam fusion reactor conceptual design  

Science Conference Proceedings (OSTI)

The LIBRA light ion beam fusion commercial reactor study is a self-consistent conceptual design of a 330 MWe power plant with an accompanying economic analysis. Fusion targets are imploded by 4-MJ-shaped pulses of 30 MeV Li ions at a rate of 3 Hz. The target gain is 80, leading to a yield of 320 MJ. The high intensity part of the ion pulse is delivered by 16 diodes through 16 separate z-pinch plasma channels formed in 100 torr of helium with trace amounts of lithium. The blanket is an array of porous flexible silicon carbide tubes with Li/sub 17/Pb/sub 83/ flowing downward through them. These tubes (INPORT units) shield the target chamber wall from both neutron damage and the shock overpressure of the target explosion. The target chamber is a right circular cylinder, 8.7 meters in diameter. The target chamber is ''self-pumped'' by the target explosion generated overpressure into a surge tank partially filled with liquid that surrounds the target chamber. This scheme refreshes the chamber at the desired 3 Hz frequency without excessive pumping demands. The blanket multiplication is 1.2 and the tritium breeding ratio is 1.4. The direct capital cost of LIBRA is estimated to be $2200/kWe. 12 refs., 9 figs., 1 tab.

Moses, G.A.; Kulcinski, G.L.; Bruggink, D.; Engelstad, R.; Lovell, E.; MacFarlane, J.; Musicki, Z.; Peterson, R.; Sawan, M.; Sviatoslavsky, I.

1988-01-01T23:59:59.000Z

154

Direct drive heavy-ion-beam inertial fusion at high coupling efficiency  

SciTech Connect

Issues with coupling efficiency, beam illumination symmetry, and Rayleigh-Taylor instability are discussed for spherical heavy-ion-beam-driven targets with and without hohlraums. Efficient coupling of heavy-ion beams to compress direct-drive inertial fusion targets without hohlraums is found to require ion range increasing several-fold during the drive pulse. One-dimensional implosion calculations using the LASNEX inertial confinement fusion target physics code shows the ion range increasing fourfold during the drive pulse to keep ion energy deposition following closely behind the imploding ablation front, resulting in high coupling efficiencies (shell kinetic energy/incident beam energy of 16% to 18%). Ways to increase beam ion range while mitigating Rayleigh-Taylor instabilities are discussed for future work.

Logan, B.G.; Perkins, L.J.; Barnard, J.J.

2008-05-16T23:59:59.000Z

155

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

Science Conference Proceedings (OSTI)

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.

Winkelmann, T.; Cee, R.; Haberer, T.; Naas, B.; Peters, A. [Heidelberger Ionenstrahl-Therapie Centrum (HIT), D-69120 Heidelberg (Germany)

2012-02-15T23:59:59.000Z

156

An alternative method for metallization by laser and ion beam irradiation  

Science Conference Proceedings (OSTI)

A scanning Ar+ laser beam and a focused 30 keV Ga+ ion beam (FIB) have been used to transform an insulating (or high-resistivity semiconducting) noble metal oxide film to a conducting layer, Resulting from these experiments we propose ... Keywords: interconnects, ion irradiation, laser application, metallization

F. Machalett; K. Edinger; M. Diegel; K. Steenbeck

2002-04-01T23:59:59.000Z

157

EXTRACTION OF HIGHLY CHARGED AU IONS FROM A MULTIAMPHERE ELECTRON BEAM EBIS AT BNL.  

DOE Green Energy (OSTI)

Excellent progress has been made in the operation of the BNL Electron Beam Ion Source (EBIS), which is a prototype for an EBIS that could meet requirements for a RHIC preinjector. We have achieved very stable operation of the electron beam at 10 A through the EBIS trap. Ion injection of low charge gold ions from a LEVA [1] ion source and subsequent extraction of these ions with most probable charge state AU{sup 34+} has been demonstrated with electron beams up to 8A. The total ion charge for gold measured on current transformer at the EBIS exit was 55nC after a 30ms confinement period. This corresponds to {approx}85% of the theoretical ion trap capacity and exceeds our goal of 50% neutralization. The collected ion charge is proportional to the electron current and the gold charge state scales with the electron current density. Details of the EBIS configuration, total charge measurements, and TOF spectra are given.

BEEBE,E.N.; ALESSI,J.G.; GOULD,O.; GRAHAM,D.; KPONOU,A.; PIKIN,A.; PRELEC,K.; RITTER,J.

2001-09-02T23:59:59.000Z

158

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

DOE Patents (OSTI)

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.

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

1994-01-01T23:59:59.000Z

159

Dynamics of neutralizing electrons during the focusing of intense heavy ions beams inside a heavy fusion reactor chamber  

E-Print Network (OSTI)

beams inside a heavy ion fusion reactor chamber * Agustin F.of a Heavy Ion Fusion reactor heavily depends on the maximum

Lifschitz, Agustin F.; Maynard, Gilles; Vay, Jean-Luc; Lenglet, Andrian

2006-01-01T23:59:59.000Z

160

Dynamics of neutralizing electrons during the focusing of intense heavy ions beams inside a heavy fusion reactor chamber  

E-Print Network (OSTI)

beams inside a heavy ion fusion reactor chamber * Agustin F.efficiency of a Heavy Ion Fusion reactor heavily depends on

Lifschitz, Agustin F.; Maynard, Gilles; Vay, Jean-Luc; Lenglet, Andrian

2006-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

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

E-Print Network (OSTI)

LBNL/PUP-928 HI FAN 1484 White Paper on Ion Beam Transportbegin preparation of this white paper on ion beam transport.each Laboratory This white paper is a result of that meeting

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

2005-01-01T23:59:59.000Z

162

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

Science Conference Proceedings (OSTI)

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.

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

2005-05-04T23:59:59.000Z

163

APPARATUS FOR CONTROLLING THE POSITION OF AN ION BEAM IN A CALUTRON  

DOE Patents (OSTI)

ABS>This patent relates to improvements in electric discharge devices of the calutron type for separation of the isotopes of an element from the freely occurring composition. The improvement constitutes means for the continuous control of the path of an ion beam to obtain maximum reception in a receiver compartment. Withdrawal of the ions from the source is accomplished by an accelerator electrode placed at a positive potential with respect to the receiver. The ions are projected through a magnetic field perpendicular to the direction of motion towards a receiver. In order to obtain a signal representative of the magnitude of ions received from a particular ion-beam in its compartment, an electrode is disposed in the compartment. The signal from the compartment electrode controls the voltage of the acccleratimg electrodc through appropriate circuitry to maintain the path of the particular ion beam optimum for maximum ion current in the compartment.

Lawrence, E.O.

1958-01-01T23:59:59.000Z

164

Anomalous electron heating and energy balance in an ion beam generated plasma  

DOE Green Energy (OSTI)

The plasma described in this report is generated by a 15 to 34 kV ion beam, consisting primarily of protons, passing through an H/sub 2/ gas cell neutralizer. Plasma ions (or ion-electron pairs) are produced by electron capture from (or ionization of) gas molecules by beam ions and atoms. An explanation is provided for the observed anomalous behavior of the electron temperature (T/sub e/): a step-lite, nearly two-fold jump in T/sub e/ as the beam current approaches that which minimizes beam angular divergence; insensitivity of T/sub e/ to gas pressure; and the linear relation of T/sub e/ to beam energy.

Guethlein, G.

1987-04-01T23:59:59.000Z

165

An Ion Guide for the Production of a Low Energy Ion Beam of Daughter Products of $\\alpha$-Emitters  

E-Print Network (OSTI)

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.

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

2006-01-01T23:59:59.000Z

166

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

E-Print Network (OSTI)

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.

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

2006-05-22T23:59:59.000Z

167

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

DOE Patents (OSTI)

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.

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

1998-01-01T23:59:59.000Z

168

Light ion sources and target results on PBFA II (Particle Beam Fusion Accelerator II)  

Science Conference Proceedings (OSTI)

Advances in ion beam theory, diagnostics, and experiments in the past two years have enabled efficient generation of intense proton beams on PBFA II, and focusing of the beam power to 5.4 TW/cm{sup 2} on a 6-mm-diameter target. Target experiments have been started with the intense proton beams, since the range of protons at 4--5 MeV is equivalent to that of lithium at 30 MeV. Three series of experiments have been conducted using planar, conical, and cylindrical targets. These tests have provided information on ion beam power density, uniformity, and energy deposition. In order to increase the power density substantially for target implosion experiments, we are now concentrating on development of high voltage lithium ion beams. 10 refs., 13 figs.

Cook, D.L.; Bailey, J.E.; Bieg, K.W.; Bloomquist, D.D.; Coats, R.S.; Chandler, G.C.; Cuneo, M.E.; Derzon, M.S.; Desjarlais, M.P.; Dreike, P.L.; Dukart, R.J.; Gerber, R.A.; Johnson, D.J.; Leeper, R.J.; Lockner, T.R.; McDaniel, D.H.; Maenchen, J.E.; Matzen, M.K.; Mehlhorn, T.A.; Mix, L.P.; Moats, A.R.; Nelson, W.E.; Pointon, T.D.; Pregenzer, A.L.; Quintenz, J.P.; Renk, T.J.; Rosenthal, S.E.; Ruiz, C.L.; Slutz, S.A.; Stinnett, R

1990-01-01T23:59:59.000Z

169

Applications of laser produced ion beams to nuclear analysis of materials  

Science Conference Proceedings (OSTI)

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.

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

2012-07-11T23:59:59.000Z

170

Hard surfaced polymeric materials by ion beam processing  

DOE Green Energy (OSTI)

Initially, both General Motors and Lockheed Martin Energy Systems, Inc. were interested in altering the surface properties of polymers using ion beam technologies. Specifically, GM wished to treat the nylon that is used to encapsulate automotive assemblies so that it would be impervious to the alcohols and ethers used in present day blends of gasoline. Fuel oxygenates such as methanol can rapidly permeate the nylon encapsulant and tend to corrode the components within the assemblies. Once the CRADA was initiated, GM learned about the cleaning/decontamination expertise that was available at the Oak Ridge Y-12 Plant. Because GM was also interested in solving contamination issues related to these assemblies, GM worked with Lockheed Martin Energy Systems, Inc. to amend the CRADA to include such issues. Y-12 was eager to share its environmentally friendly, cleaning/decontamination expertise and also to expand upon its knowledge in this area. GM provided funds into the CRADA in order to address these contamination issues. Further on into the CRADA, GM put even more emphasis on the decontamination issues. This change in direction resulted because of rapid progress on the decontamination issues and, secondly, because GM changed its component material from nylon to the highly impervious polyphenylene sulfide.

Simandl, R.F. [Lockheed Martin Energy Systems, Inc., Oak Ridge, TN (United States); Rose, D. [Delphi Energy and Engine Management Systems, Flint, MI (United States)

1996-09-27T23:59:59.000Z

171

Heavy Ion Beams for Investigation of Thermophysical Properties  

E-Print Network (OSTI)

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

Igor Iosilevskiy

2010-05-23T23:59:59.000Z

172

A Stripline Fast Faraday Cup for measuring GHz structure of ion beams  

DOE Patents (OSTI)

The Stripline Fast Faraday Cup is a device which is used to quantitatively and qualitatively measure gigahertz time structure characteristics of ion beams with energies up to at least 30 Mev per nucleon. A stripline geometry is employed in conjunction with an electrostatic screen and a Faraday cup to provide for analysis of the structural characteristics of an ion beam. The stripline geometry allows for a large reduction in the size of the instrument while the electrostatic screen permits measurements of the properties associated with low speed ion beams.

Bogaty, J.M.

1990-01-01T23:59:59.000Z

173

Progress toward a microsecond duration, repetitive, intense-ion beam for active spectroscopic measurements on ITER  

SciTech Connect

The authors describe the design of an intense, pulsed, repetitive, neutral beam based on magnetically insulated diode technology for injection into ITER for spectroscopic measurements of thermalizing alpha particle and thermal helium density profiles, ion temperature, plasma rotation, and low Z impurity concentrations in the confinement region. The beam is being developed to enhance low signal-to-noise ratios expected with conventional steady-state ion beams because of severe beam attenuation and intense bremstrahlung emission. A 5 GW (e.g., 100 keV, 50 kA) one-microsecond-duration beam would increase the signal by 10{sup 3} compared to a conventional 5 MW beam with signal-to-noise ratios comparable to those from a chopped conventional beam in one second.

Davis, H.A.; Bartsch, R.R.; Barnes, C.W. [and others

1996-06-01T23:59:59.000Z

174

Ion beam development for the needs of the JYFL nuclear physics programme  

SciTech Connect

The increased requirements towards the use of higher ion beam intensities motivated us to initiate the project to improve the overall transmission of the K130 cyclotron facility. With the facility the transport efficiency decreases rapidly as a function of total beam intensity extracted from the JYFL ECR ion sources. According to statistics, the total transmission efficiency is of the order of 10% for low beam intensities (I{sub total}{<=}0.7 mA) and only about 2% for high beam intensities (I{sub total}>1.5 mA). Requirements towards the use of new metal ion beams for the nuclear physics experiments have also increased. The miniature oven used for the production of metal ion beams at the JYFL is not able to reach the temperature needed for the requested metal ion beams. In order to fulfill these requirements intensive development work has been performed. An inductively and a resistively heated oven has successfully been developed and both are capable of reaching temperatures of about 2000 deg. C. In addition, sputtering technique has been tested. GEANT4 simulations have been started in order to better understand the processes involved with the bremsstrahlung, which gives an extra heat load to cryostat in the case of superconducting ECR ion source. Parallel with this work, a new advanced ECR heating simulation program has been developed. In this article we present the latest results of the above-mentioned projects.

Koivisto, H.; Suominen, P.; Ropponen, T.; Ropponen, J.; Koponen, T.; Savonen, M.; Toivanen, V.; Wu, X.; Machicoane, G.; Stetson, J.; Zavodszky, P.; Doleans, M.; Spaedtke, P.; Vondrasek, R.; Tarvainen, O. [Department of Physics, University of Jyvaeskylae, FIN-40014 University of Jyvaeskylae (Finland); National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Gesellschaft fur Schwerionenforschung (GSI), Darmstadt D-64291 (Germany); Argonne National Laboratory, Argonne, Illinois 60439 (United States); Los Alamos National Laboratory, Los Alamos, 87545 New Mexico (United States)

2008-02-15T23:59:59.000Z

175

LENDA, a Low Energy Neutron Detector Array for experiments with radioactive beams in inverse kinematics  

E-Print Network (OSTI)

The Low Energy Neutron Detector Array (LENDA) is a neutron time-of-flight (TOF) spectrometer developed at the National Superconducting Cyclotron Lab- oratory (NSCL) for use in inverse kinematics experiments with rare isotope beams. Its design has been motivated by the need to study the spin-isospin response of unstable nuclei using (p, n) charge-exchange reactions at intermediate energies (> 100 MeV/u). It can be used, however, for any reaction study that involves emission of low energy neutrons (150 keV - 10 MeV). The array consists of 24 plastic scintillator bars and is capable of registering the recoiling neutron energy and angle with high detection efficiency. The neutron energy is determined by the time-of-flight technique, while the position of interaction is deduced using the timing and energy information from the two photomultipliers of each bar. A simple test setup utilizing radioactive sources has been used to characterize the array. Results of test measurements are compared with simulations. A neutron energy threshold of 20 % for neutrons below 4 MeV have been obtained.

G. Perdikakis; M. Sasano; Sam M. Austin; D. Bazin; C. Caesar; S. Cannon; J. M. Deaven; H. J. Doster; C. J. Guess; G. W. Hitt; J. Marks; R. Meharchand; D. T. Nguyen; D. Peterman; A. Prinke; M. Scott; Y. Shimbara; K. Thorne; L. Valdez; R. G. T. Zegers

2011-11-17T23:59:59.000Z

176

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

E-Print Network (OSTI)

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 ...

Henestroza, Enrique

2006-01-01T23:59:59.000Z

177

Direct drive heavy-ion-beam inertial fusion at high coupling efficiency  

E-Print Network (OSTI)

M J of fusion yield. This NIF capsule design ab- sorbs 200capsules the size of the NIF capsule with heavy-ion beams (designs emerge, and, if the NIF's ignition campaign is also

Logan, B.G.

2008-01-01T23:59:59.000Z

178

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

E-Print Network (OSTI)

of fusion yield [16]. This NIF capsule design absorbs 200 kJcapsules the size of the NIF capsule with heavy ion beams (designs emerge, and, i f the NIF's ignition campaign is also

Logan, B. Grant

2008-01-01T23:59:59.000Z

179

Summary of informal workshop on state of ion beam facilities for atomic physics research  

SciTech Connect

The present state of ion beam facilities for atomic physics research in the United States is assessed by means of a questionnaire and informal workshop. Recommendations for future facilities are given. 3 refs.

Jones, K.W.; Cocke, C.L.; Datz, S.; Kostroun, V.

1984-11-13T23:59:59.000Z

180

Preparation of thin films by ablation with ANACONDA ion beam generator  

Science Conference Proceedings (OSTI)

Thin films of silicon carbide are produced by using the technology of ion beam evaporation. Various analytical methods are used to analyze film thickness, film composition and crystallization for samples obtained with different target-substrate distances.

Yatsui, K.; Jiang, W. [Nagaoka Univ. of Technology (Japan). Lab. of Beam Technology; Davis, H.A.; Olson, J.C.; Waganaar, W.J.; Rej, D. [Los Alamos National Lab., NM (United States)

1996-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Design, optimization, and selectivity of inorganic ion-exchangers for radioactive waste remediation  

E-Print Network (OSTI)

The processes of development of nuclear weapons resulted in accumulation of thousands of curies of high-level radioactive waste. Liquid waste produced in the US has been stored in carbon steel tanks in highly alkaline (1-3 M NaOH, 6 M sodium salts) media for fifty years and leakage has occurred. One of the approaches to the solution of the problem of radioactive waste is to adsorb the nuclides on highly selective ion-exchange material, solidify in a glass matrix and dispose in a geological formation. The use of the ion-exchange technology is limited by the time of the sorbent-solution contact required to reduce the activity of the streams to acceptable levels. Inorganic ion-exchangers are promising materials due to their high radiation stability, extreme selectivity, and compatibility with the glass matrix. The contact time can be reduced by improving selectivities, kinetics, and capacities of the materials towards the target ions. This can be accomplished in part through understanding of the origin of ion-exchange selectivity. Crystalline zeotypes with minerals sitinakite (ideal formula Na2Ti2O3SiO4??2H2O) and pharmacosiderite (HM3(TO)4(GeO4)x(SiO4)3-x M = Cs+, Na+, K+, T=Nb5+, Ge4+, Ti4+) structures are excellent candidates for selectivity studies because of their ion-exchange properties tunable by alterations of synthetic procedures, and isomorphous framework substitution. The Nb-substitution in titanium sites reduces the framework charge, whereas Ge substitution decreases the unit cell size if in titanium sites and increases if it in silicon sites. The compounds were hydrothermally synthesized in Ti/Si, Ti/Nb/Si, Ti/Ge/Si forms and characterized by structural and ion-exchange studies. The 25% Nb substitution in titanosilicate sitinakite resulted in enhanced selectivity for cesium and additional bond formation of cesium within the channel. The selectivity for cesium in germanium substituted pharmacosiderite also was correlated with the coordination environment within the channel. In the advanced stages of this study semi-crystalline (sodium nonatitanate) and amorphous (monosodium titanate) materials also were considered because of their remarkable strontium selectivity. In situ X-ray diffraction techniques revealed that the sodium nonatitanate precedes the formation of the TS phase in hydrothermal synthesis. This knowledge allowed us to design and synthesize material for combined cesium and strontium removal.

Medvedev, Dmitry Gennadievich

2004-08-01T23:59:59.000Z

182

Stabilization of tearing instability and heating of plasma ions by a modulated particle beam  

SciTech Connect

The tearing instability is considered for nonisothermal plasma penetrated by a low-velocity charged-particle beam. Possible stabilization of this instability due to the transformation of the high-frequency wave energy into the energy of a nonlinear ion-acoustic wave is discussed. This phenomenon is equivalent to the nonlinear absorption of the high-frequency waves. The efficiency of heating of heavy particles (ions) by a charged-particle beam is estimated.

Fainshtein, S.M.

1976-09-01T23:59:59.000Z

183

Concentrated ion beam emitted from an enlarged cylindrical-anode-layer Hall plasma accelerator and mechanism  

SciTech Connect

An enlarged cylindrical-anode-layer Hall plasma accelerator with an outlet diameter of 150 mm is experimentally demonstrated to produce a concentrated ion beam, especially at a high discharge voltage, with a high current utilization efficiency of up to {approx}0.9. Numerical investigation based on the three-dimensional particle-in-cell method is performed to study the ion dynamics and elucidate the origin of the ion beam characteristics. The simulation results reveal that the equipotential lines play an important role in the surface near the anode emitting the ions. The ion emitting surface is determined by the magnetic field lines near the anode and the magnetic mirror contributes to the concentrated beam significantly. The high current utilization efficiency results from the appropriate obliquity of the magnetic mirror.

Geng, S. F.; Wang, C. X. [Southwestern Institute of Physics, Chengdu 610041 (China); Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Tang, D. L.; Qiu, X. M. [Southwestern Institute of Physics, Chengdu 610041 (China); Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong)

2013-01-28T23:59:59.000Z

184

INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMS  

E-Print Network (OSTI)

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

Sharp, W. M.

2011-01-01T23:59:59.000Z

185

ION-MOLECULE INTERACTIONS IN CROSSED-BEAMS  

E-Print Network (OSTI)

is another important thermal energy technique, but operatesof the reactants. The thermal energy beams were prepared bythe very important thermal energy range is On the plus side

Hansen, Steven George

2010-01-01T23:59:59.000Z

186

AN INTENSE NON-RELATIVISTIC CESIUM ION BEAM  

E-Print Network (OSTI)

of the Diagnostic Tank Showing ESP Example Data Set of EBPElectron Beam Probe (ESP) was developed as an independentbetween measurements with the ESP and the small, movable

Lampel, M.C.

2010-01-01T23:59:59.000Z

187

Analytical and Numerical Studies of the Complex Interaction of a Fast Ion Beam Pulse with a Background Plasma  

SciTech Connect

Plasma neutralization of an intense ion beam pulse is of interest for many applications, including plasma lenses, heavy ion fusion, high energy physics, etc. Comprehensive analytical, numerical, and experimental studies are underway to investigate the complex interaction of a fast ion beam with a background plasma. The positively charged ion beam attracts plasma electrons, and as a result the plasma electrons have a tendency to neutralize the beam charge and current. A suite of particle-in-cell codes has been developed to study the propagation of an ion beam pulse through the background plasma. For quasi-steady-state propagation of the ion beam pulse, an analytical theory has been developed using the assumption of long charge bunches and conservation of generalized vorticity. The analytical results agree well with the results of the numerical simulations. The visualization of the data obtained in the numerical simulations shows complex collective phenomena during beam entry into and ex it from the plasma.

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

2003-11-25T23:59:59.000Z

188

Annealing effects in hydrogenated silicon nitride films during high energy ion beam irradiation  

SciTech Connect

The annealing effects during energy recoil detection (ERD) analysis on the structure of hydrogenated silicon nitride film have been investigated by using fourier transform infrared (FTIR) spectroscopy. Hydrogenated silicon nitride films were prepared by plasma enhanced chemical vapor deposition with various substrate temperatures. A 2.5 MeV {sup 4}He{sup ++} ion beam was irradiated onto the film in a vacuum chamber at room temperature. The ERD signal was measured after various ion doses in order to determine the loss of hydrogen counts induced by the ion beam. The IR absorption spectrum was obtained in order to follow the film structural change which occurred due to the ion beam. The films deposited at 200 and 300 C show a significant decrease in the ERD count with increasing ion beam dose, while the film deposited at 400 C, shows no significant changes. The IR absorption peak position for Si-N stretching (830 cm{sup {minus}1}) shifted to smaller wave numbers after ion beam irradiation, while the Si-H stretching (2,160 cm{sup {minus}1}) shifted to the opposite direction. The peak position for N-H (3,360 cm{sup {minus}1}) shows no noticeable changes. Normalized peak area for the Si-N stretching increased after ion beam irradiation. The Si-H peak area decreased slightly. The N-H peak area decreased significantly. A recombination mechanism of the N and H radicals with excess Si radical coming from Si-Si bonds in Si-rich silicon nitride films has been suggested to explain the IR absorption spectral changes which have occurred due to ion beam irradiation.

Lee, J.W. [ETRI, Taejon (Korea, Republic of)]|[KAIST, Taejon (Korea, Republic of); Lee, S.H.; Yoo, H.J. [ETRI, Taejon (Korea, Republic of); Jhon, M.S.; Ryoo, R. [KAIST, Taejon (Korea, Republic of)

1995-09-01T23:59:59.000Z

189

Nonlinear Plasma Waves Excitation by Intense Ion Beams in Background Plasma  

SciTech Connect

Plasma neutralization of an intense ion pulse is of interest for many applications, including plasma lenses, heavy ion fusion, cosmic ray propagation, etc. An analytical electron fluid model has been developed to describe the plasma response to a propagating ion beam. The model predicts very good charge neutralization during quasi-steady-state propagation, provided the beam pulse duration {tau}{sub b} is much longer than the electron plasma period 2{pi}/{omega}{sub p}, where {omega}{sub p} = (4{pi}e{sup 2}n{sub p}/m){sup 1/2} is the electron plasma frequency and n{sub p} is the background plasma density. In the opposite limit, the beam pulse excites large-amplitude plasma waves. If the beam density is larger than the background plasma density, the plasma waves break. Theoretical predictions are compared with the results of calculations utilizing a particle-in-cell (PIC) code. The cold electron fluid results agree well with the PIC simulations for ion beam propagation through a background plasma. The reduced fluid description derived in this paper can provide an important benchmark for numerical codes and yield scaling relations for different beam and plasma parameters. The visualization of numerical simulation data shows complex collective phenomena during beam entry and exit from the plasma.

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

2004-04-15T23:59:59.000Z

190

Simulation of an RFQ (radio-frequency quadruple) funnel for heavy-ion beams  

Science Conference Proceedings (OSTI)

Use of the magnetic force to focus and deflect heavy-ion beams is marginal at low ion velocities. Low-emittance-growth funnels using discrete magnetic elements are difficult to design for these beams. We show that a new type of radio-frequency quadruple (RFQ) funnel is especially suitable for this application. Simulation procedures, which include space-charge and image effects, have produced a high-quality funnel design for 20-MeV Bi/sup +1/ ions. 4 refs., 4 figs., 2 tabs.

Guy, F.W.; Stokes, R.H.

1989-01-01T23:59:59.000Z

191

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

SciTech Connect

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.

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

2010-04-30T23:59:59.000Z

192

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

Science Conference Proceedings (OSTI)

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.

Wang, Lanfa; Pivi, Mauro; /SLAC

2012-05-30T23:59:59.000Z

193

Negative-ion sources for neutral-beam systems  

Science Conference Proceedings (OSTI)

There are three main methods now used to produce negative hydrogen ions: charge exchange, volume production, and surface production, and this paper briefly describes these three systems.

Ehlers, K.W.

1983-06-01T23:59:59.000Z

194

Ultra-sensitive high-precision spectroscopy of a fast molecular ion beam  

Science Conference Proceedings (OSTI)

Direct spectroscopy of a fast molecular ion beam offers many advantages over competing techniques, including the generality of the approach to any molecular ion, the complete elimination of spectral confusion due to neutral molecules, and the mass identification of individual spectral lines. The major challenge is the intrinsic weakness of absorption or dispersion signals resulting from the relatively low number density of ions in the beam. Direct spectroscopy of an ion beam was pioneered by Saykally and co-workers in the late 1980s, but has not been attempted since that time. Here, we present the design and construction of an ion beam spectrometer with several improvements over the Saykally design. The ion beam and its characterization have been improved by adopting recent advances in electrostatic optics, along with a time-of-flight mass spectrometer that can be used simultaneously with optical spectroscopy. As a proof of concept, a noise-immune cavity-enhanced optical heterodyne molecular spectroscopy (NICE-OHMS) setup with a noise equivalent absorption of {approx}2 x 10{sup -11} cm{sup -1} Hz{sup -1/2} has been used to observe several transitions of the Meinel 1-0 band of N{sub 2}{sup +} with linewidths of {approx}120 MHz. An optical frequency comb has been used for absolute frequency calibration of transition frequencies to within {approx}8 MHz. This work represents the first direct spectroscopy of an electronic transition in an ion beam, and also represents a major step toward the development of routine infrared spectroscopy of rotationally cooled molecular ions.

Mills, Andrew A.; Siller, Brian M.; Porambo, Michael W.; Perera, Manori; Kreckel, Holger [Department of Chemistry, University of Illinois, Urbana, Illinois 61801 (United States); McCall, Benjamin J. [Department of Chemistry, University of Illinois, Urbana, Illinois 61801 (United States); Departments of Physics and Astronomy, University of Illinois, Urbana, Illinois 61801 (United States)

2011-12-14T23:59:59.000Z

195

THE KINETICS OF THE ELECTROCHEMICAL DEPOSITION OF RADIOACTIVE IONS ON METAL SURFACES  

SciTech Connect

The Nernst-Brunner equation hss been applied to the electrochemical deposition of carrier-free radioactive ions on metal foils in a modified form to include decay and growth. The modified equation was shown to hold for the depesition of B/sup 212/(ThC) and Bi/sup 210/(RaE) on nickel foils from weak hydrochloric acid solutions under the following conditions: pure Bl/sup 212/ in equilibrium with Pb/sup 212/(ThB), Bi/sup 212/ in equilibrium with Th/sup 228/ (RdTh), and Bi/sup 210/ in equilibrium with Pb/sup 210/(RaD), Some indications of the purity of the deposited radio-bismuth are given. (auth)

Fahland, J.; Herrmann, G.; Strassmann, F.

1958-10-01T23:59:59.000Z

196

Sub-10-nm lithography with light-ion beams  

E-Print Network (OSTI)

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 ...

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

2012-01-01T23:59:59.000Z

197

Figures of merit for focusing mega-electron-volt ion beams in biomedical imaging and proton beam writing  

SciTech Connect

A figure of merit (FOM) has been developed for focusing quadrupole multiplet lenses for ion micro- and nanobeam systems. The method which is based on measurement of the central peak of the two-dimensional autocorrelation function of an image provides separate FOM for the horizontal and vertical directions. The approach has been tested by comparison with the edge widths obtained by nonlinear fitting the edge widths of a Ni grid and found to be reliable. The FOM has the important advantage for ion beam imaging of biomedical samples that the fluence needed is considerably lower than for edge fitting.

Ren Minqin; Whitlow, Harry J.; Ananda Sagari, A. R.; Kan, Jeroen A. van; Osipowicz, Thomas; Watt, Frank [Department of Physics, University of Jyvaeskylae, P.O. Box 35 (YFL), FIN-40014 (Finland); Centre for Ion Beam Applications, Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542 (Singapore)

2008-01-01T23:59:59.000Z

198

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

DOE Green Energy (OSTI)

Significant experimental and theoretical progress in the U.S heavy-ion fusion (HIF) program is reported in modeling and measurements of intense space-charge-dominated heavy ion and electron beams. Measurements of the transport of a well-matched and aligned high current (0.2A) 1.0 MeV potassium ion beam through 10 electric quadrupoles, with a fill factor of 60%, shows no emittance growth within experimental measurement uncertainty, as expected from the simulations. Another experiment shows that passing a beam through an aperture can reduce emittance to near the theoretical limits, and that plasma neutralization of the beam's space-charge can greatly reduce the focal spot radius. Measurements of intense beamlet current density, emittance, charge-state purity, and energy spread from a new, high-brightness, Argon plasma source for HIF experiments are described. New theory and simulations of neutralization of intense beam space charge with plasma in various focusing chamber configurations indicate that near-emittance-limited beam focal spot sizes can be obtained even with beam perveance an order of magnitude higher than in earlier HIF focusing experiments.

Logan, B.G.; Baca, D.; Barnard, J.J.; Bieniosek, F.M.; Burkhart, C.; Celata, C.M.; Chacon-Golcher, E.; Cohen, R.H.; Davidson, R.C.; Efthimion P.; Faltens, A.; Friedman, A.; Grisham, L.; Grote, D.P.; Haber, I.; Henestroza, E.; Kaganovich, I.; Kishek, R.A.; Kwan, J.W.; Lee, E.P.; Lee, W.W.; Leitner, M.; Lund, S.M.; Meier, W.R.; Molvik, A.W.; O'Shea, P.G.; Olson, C.; Olson, R.E.; Prost, L.R.; Qin, H.; Reiser, M.; Rose, D.; Sabbi, G.; Seidl, P.A.; Sharp, W.M.; Shuman, D.B.; Vay, J-L.; Waldron, W.L.; Welch, D.; Westenskow, G.A.; Yu, S.S.

2002-10-01T23:59:59.000Z

199

Model simulations of continuous ion injection into electron-beam ion source trap with slanted electrostatic mirror  

Science Conference Proceedings (OSTI)

The efficiency of trapping ions in an electron-beam ion source (EBIS) is of primary importance for many applications requiring operations with externally produced ions: RIA breeders, ion sources, and traps. At the present time, the most popular method of ion injection is pulsed injection, when short bunches of ions get trapped in a longitudinal trap while traversing the trap region. Continuous trapping is a challenge for EBIS devices because mechanisms which reduce the longitudinal ion energy per charge in a trap (cooling with residual gas, energy exchange with other ions, and ionization) are not very effective, and accumulation of ions is slow. A possible approach to increase trapping efficiency is to slant the mirror at the end of the trap which is opposite to the injection end. A slanted mirror will convert longitudinal motion of ions into transverse motion, and, by reducing their longitudinal velocity, prevent these ions from escaping the trap on their way out. The trade-off for the increased trapping efficiency this way is an increase in the initial transverse energy of the accumulated ions. The slanted mirror can be realized if the ends of two adjacent electrodes, drift tubes, which act as an electrostatic mirror, are machined to produce a slanted gap, rather than an upright one. Applying different voltages to these electrodes will produce a slanted mirror. The results of two-dimensional (2D) and three-dimensional (3D) computer simulations of the ion injection into an EBIS are presented using simplified models of an EBIS with conical (2D simulations) and slanted (3D simulations) mirror electrodes.

Pikin, A.; Kponou, A.; Alessi, J. G.; Beebe, E. N.; Prelec, K.; Raparia, D. [Brookhaven National Laboratory, Upton, New York 11973 (United States)

2008-02-15T23:59:59.000Z

200

RADIO-ACTIVE TRANSDUCER  

DOE Patents (OSTI)

ABS>ure the change in velocity of a moving object. The transducer includes a radioactive source having a collimated beam of radioactive particles, a shield which can block the passage of the radioactive beam, and a scintillation detector to measure the number of radioactive particles in the beam which are not blocked by the shield. The shield is operatively placed across the radioactive beam so that any motion normal to the beam will cause the shield to move in the opposite direction thereby allowing more radioactive particles to reach the detector. The number of particles detected indicates the acceleration. (AEC)

Wanetick, S.

1962-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

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

SciTech Connect

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.

Keller, Roderich [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

202

In situ nanomechanical testing in focused ion beam and scanning electron microscopes  

Science Conference Proceedings (OSTI)

The recent interest in size-dependent deformation of micro- and nanoscale materials has paralleled both technological miniaturization and advancements in imaging and small-scale mechanical testing methods. Here we describe a quantitative in situ nanomechanical testing approach adapted to a dual-beam focused ion beam and scanning electron microscope. A transducer based on a three-plate capacitor system is used for high-fidelity force and displacement measurements. Specimen manipulation, transfer, and alignment are performed using a manipulator, independently controlled positioners, and the focused ion beam. Gripping of specimens is achieved using electron-beam assisted Pt-organic deposition. Local strain measurements are obtained using digital image correlation of electron images taken during testing. Examples showing results for tensile testing of single-crystalline metallic nanowires and compression of nanoporous Au pillars will be presented in the context of size effects on mechanical behavior and highlight some of the challenges of conducting nanomechanical testing in vacuum environments.

Gianola, D. S. [Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Institute for Applied Materials, Karlsruhe Institute of Technology, Karlsruhe (Germany); Sedlmayr, A.; Moenig, R.; Kraft, O. [Institute for Applied Materials, Karlsruhe Institute of Technology, Karlsruhe (Germany); Volkert, C. A. [Institute for Materials Physics, Georg-August University of Goettingen, Goettingen (Germany); Major, R. C.; Cyrankowski, E.; Asif, S. A. S.; Warren, O. L. [Hysitron, Inc., Minneapolis, Minnesota 55344 (United States)

2011-06-15T23:59:59.000Z

203

Advanced time-stamped total data acquisition control front-end for MeV ion beam microscopy and proton beam writing  

Science Conference Proceedings (OSTI)

Many ion-matter interactions exhibit sub-@ms time dependences such as, fluorophore emission quenching and ion beam induced charge (IBIC). Conventional event-mode MeV ion microbeam data acquisition systems discard the time information. Here we describe ... Keywords: Data acquisition, FPGA, Front-end, Microbeam, Time-stamping

Henri Kivistö; Mikko Rossi; Pete Jones; Rattanaporn Norarat; Nitipon Puttaraksa; Timo Sajavaara; Mikko Laitinen; VäInö HäNninen; Kimmo Ranttila; Pauli Heikkinen; Leona Gilbert; Varpu MarjomäKi; Harry J. Whitlow

2013-02-01T23:59:59.000Z

204

Performance of the H{sup -} Ion Source Supporting 1-MW Beam Operations at SNS  

Science Conference Proceedings (OSTI)

The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory reached 1-MW of beam power in September 2009, and now routinely operates near 1-MW for the production of neutrons. This paper reviews the performance, operational issues, implemented and planned mitigations of the SNS H{sup -} ion source to support such high power-level beams with high availability. Some results from R and D activities are also briefly described.

Han, B. X.; Hardek, T.; Kang, Y.; Murray, S. N. Jr.; Pennisi, T. R.; Piller, C.; Santana, M.; Welton, R. F.; Stockli, M. P. [Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)

2011-09-26T23:59:59.000Z

205

Performance of the H- Ion Source Supporting 1-MW Beam Operations at SNS  

Science Conference Proceedings (OSTI)

The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory reached 1-MW of beam power in September 2009, and now routinely operates near 1-MW for the production of neutrons. This paper reviews the performance, operational issues, implemented and planned mitigations of the SNS H- ion source to support such high power-level beams with high availability. Some results from R&D activities are also briefly described.

Han, Baoxi [ORNL; Hardek, Thomas W [ORNL; Kang, Yoon W [ORNL; Murray Jr, S N [ORNL; Pennisi, Terry R [ORNL; Piller, Chip [ORNL; Santana, Manuel [ORNL; Welton, Robert F [ORNL; Stockli, Martin P [ORNL

2011-01-01T23:59:59.000Z

206

CANCELLED Microwave Ion Source and Beam Injection for anAccelerator-Driven Neut ron Source  

DOE Green Energy (OSTI)

An over-dense microwave driven ion source capable of producing deuterium (or hydrogen) beams at 100-200 mA/cm{sup 2} and with atomic fraction > 90% was designed and tested with an electrostatic low energy beam transport section (LEBT). This ion source was incorporated into the design of an Accelerator Driven Neutron Source (ADNS). The other key components in the ADNS include a 6 MeV RFQ accelerator, a beam bending and scanning system, and a deuterium gas target. In this design a 40 mA D{sup +} beam is produced from a 6 mm diameter aperture using a 60 kV extraction voltage. The LEBT section consists of 5 electrodes arranged to form 2 Einzel lenses that focus the beam into the RFQ entrance. To create the ECR condition, 2 induction coils are used to create {approx} 875 Gauss on axis inside the source chamber. To prevent HV breakdown in the LEBT a magnetic field clamp is necessary to minimize the field in this region. Matching of the microwave power from the waveguide to the plasma is done by an autotuner. They observed significant improvement of the beam quality after installing a boron nitride liner inside the ion source. The measured emittance data are compared with PBGUNS simulations.

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

2007-02-27T23:59:59.000Z

207

Model for nonlinear evolution of localized ion ring beam in magnetoplasma  

SciTech Connect

An electrostatic hybrid model, which investigates the nonlinear evolution of a localized ion ring beam in a magnetoplasma, is described and applied to the generation and evolution of turbulence in the very low frequency (VLF) ({Omega}{sub ci}<{omega}<{Omega}{sub ce}) range, where {Omega}{sub ci(e)} is the ion (electron) gyro frequency. Electrons are treated as a fluid and the ions with the particle-in-cell method. Although the model is electrostatic, it includes the effects of energy loss by convection of electromagnetic VLF waves out of the instability region by utilizing a phenomenological model for effective collisions with the fluid electrons. In comparison with a more conventional electrostatic hybrid model, the new model shows much more efficient extraction of energy from the ion ring beam and reduced background plasma heating over a range of parameters.

Scales, W. A. [Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, Virginia 24061-0111 (United States); Ganguli, G.; Mithaiwala, M. [Plasma Physics Division, Naval Research Laboratory, Washington D.C. 20375 (United States); Rudakov, L. [Icarus Research, Inc., P.O. Box 30780, Bethesda, Maryland 20824-0780 (United States)

2012-06-15T23:59:59.000Z

208

Ion Beam Layer Separation of Cadmium Zinc Telluride  

Science Conference Proceedings (OSTI)

We have investigated the approach of ion induced layer separation process for layer splitting from Cadmium Zinc Telluride (CZT) bulk single crystal and transferring and bonding the separated layers with Silicon (Si) wafers. Layer separation experiments have been carried out at UES using 1 MeV H{sup +} ions from the high energy accelerator (1.7 MV Tandetron). Ion dose and annealing temperature for complete separation of 1 cmx1 cm size layers have been optimized. Bonding of CZT with Si was accomplished using various IR transmitting chalcogenide glasses. Cracking of separated CZT films was occurring for chalcogenide glass bonded films. Optimization of thermal treatment has led to the minimization of such cracks. Detailed characterizations of the separated films will be presented.

Bhattacharya, Rabi S.; He, P.; Xu, Y. [UES, Inc. 4401 Dayton-Xenia Road, Dayton, OH 45432 (United States); Goorsky, M. [University of California at Los Angeles, 10920 Wilshire Blvd, Suite 107, Los Angeles CA 90024 (United States)

2008-11-03T23:59:59.000Z

209

Development of distributed ion pumps for g-2 beam vacuum system  

Science Conference Proceedings (OSTI)

Distributed ion pumps (DIPs) will be used for the beam vacuum system of the g-2 muon storage ring. The magnetic field intensity and alignment angle at the DIP locations are not uniform. The pumping behavior of several different ion pump elements under this non-uniform magnetic field has been studied. The results are compared with the theoretical predictions. Based on these results, the optimum design of the g-2 DIPs has been developed.

Hseuh, H.C.; Mapes, M.; Snydstrup, L.

1993-06-01T23:59:59.000Z

210

Development of distributed ion pumps for g-2 beam vacuum system  

Science Conference Proceedings (OSTI)

Distributed ion pumps (DIPs) will be used for the beam vacuum system of the g-2 muon storage ring. The magnetic field intensity and alignment angle at the DIP locations are not uniform. The pumping behavior of several different ion pump elements under this non-uniform magnetic field has been studied. The results are compared with the theoretical predictions. Based on these results, the optimum design of the g-2 DIPs has been developed.

Hseuh, H.C.; Mapes, M.; Snydstrup, L.

1993-01-01T23:59:59.000Z

211

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

Science Conference Proceedings (OSTI)

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.

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

2013-01-01T23:59:59.000Z

212

Device for providing high-intensity ion or electron beam  

SciTech Connect

A thin film of a low-thermionic-work-function material is maintained on the cathode of a device for producing a high-current, low-pressure gas discharge by means of sputter deposition from an auxiliary electrode. The auxiliary electrode includes a surface with a low-work-function material, such as thorium, uranium, plutonium or one of the rare earth elements, facing the cathode but at a disposition and electrical potential so as to extract ions from the gas discharge and sputter the low-work-function material onto the cathode. By continuously replenishing the cathode film, high thermionic emissions and ion plasmas can be realized and maintained over extended operating periods.

McClanahan, Edwin D. (Richland, WA); Moss, Ronald W. (Richland, WA)

1977-01-01T23:59:59.000Z

213

Method for forming metallic silicide films on silicon substrates by ion beam deposition  

DOE Patents (OSTI)

Metallic silicide films are formed on silicon substrates by contacting the substrates with a low-energy ion beam of metal ions while moderately heating the substrate. The heating of the substrate provides for the diffusion of silicon atoms through the film as it is being formed to the surface of the film for interaction with the metal ions as they contact the diffused silicon. The metallic silicide films provided by the present invention are contaminant free, of uniform stoichiometry, large grain size, and exhibit low resistivity values which are of particular usefulness for integrated circuit production.

Zuhr, R.A.; Holland, O.W.

1989-01-24T23:59:59.000Z

214

Transport in JET H-mode Plasmas with Beam and Ion Cyclotron Heating  

Science Conference Proceedings (OSTI)

Ion Cyclotron (IC) Range of Frequency waves and neutral beam (NB) injection are planned for heating in ITER and other future tokamaks. It is important to understand transport in plasmas with NB and IC to plan, predict, and improve transport and confinement. Transport predictions require simulations of the heating profiles, and for this, accurate modeling of the IC and NB heating is needed.

R.V. Budny, et. al.

2012-07-13T23:59:59.000Z

215

Exploration of the ultimate patterning potential achievable with focused ion beams  

Science Conference Proceedings (OSTI)

In this paper, we present our work aiming to explore the nano-structuring potential of high resolution focused ion beams (FIB), a technology capable of overcoming some basic limitations of current nano-fabrication techniques and to propose new patterning ...

J. Gierak; E. Bourhis; M. N. Mérat Combes; Y. Chriqui; I. Sagnes; D. Mailly; P. Hawkes; R. Jede; L. Bruchhaus; L. Bardotti; B. Prével; A. Hannour; P. Mélinon; A. Perez; J. Ferré; J. -P. Jamet; A. Mougin; C. Chappert; V. Mathet

2005-03-01T23:59:59.000Z

216

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

Science Conference Proceedings (OSTI)

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.

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

1997-12-01T23:59:59.000Z

217

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

E-Print Network (OSTI)

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

Economou, Demetre J.

218

Low-energy ionization cooling of ions for beta beam sources  

SciTech Connect

Rubbia et al.[1] have recently suggested that multiturn passage of a low-energy ion beam (v/c {approx_equal} 0.1) through a low-Z target can be used in the production of ions useable for beta-beam sources and that ionization cooling techniques can increase the circulating beam lifetime and thus enhance that production. Some parameters in their initial discussion are somewhat optimistic, and the conditions for 3-D cooling are not completely developed. In the present paper we reconsider some features of the scenarios and suggest some variations that may be more practical. While 3-D cooling is possible at these energies, mixing of longitudinal motion with both horizontal and vertical motion is necessary to obtain simultaneous cooling in all dimensions; we suggest lattice variations that would be needed. Direct and reverse kinematics are described and explored.

Neuffer, David; /Fermilab

2007-10-01T23:59:59.000Z

219

Micromilling of Metal Alloys with Focused Ion Beam-Fabricated Tools  

SciTech Connect

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.

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

1999-11-05T23:59:59.000Z

220

Production of intense highly charged ion beams with SERSE  

E-Print Network (OSTI)

The source SERSE is operational at LNS since June 1998 and many improvements have been carried out in this period. The frequency has been increased from 14.5 GHz to 18 GHz and the use of two frequency heating has given positive results. Metallic ion production has been tested by means of a high temperature oven and the preliminary results are described. Tests of magnetic field scaling and frequency scaling have confirmed the results of previous tests with SC-ECRIS at lower frequency and seems to suggest that the upgrading of the source to higher frequency may be considered.

Gammino, S; Ciavola, G; Castro, M; Chines, F; Marletta, S; Melin, G; Briand, P; Girard, A; Ludwig, P; Seyfert, P; Guillaume, D

1999-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

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

E-Print Network (OSTI)

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.

Igor Iosilevskiy; Victor Gryaznov

2010-05-23T23:59:59.000Z

222

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

Science Conference Proceedings (OSTI)

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

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

2012-11-15T23:59:59.000Z

223

Plasma focus ion beam fluence and flux-Scaling with stored energy  

Science Conference Proceedings (OSTI)

Measurements on plasma focus ion beams include various advanced techniques producing a variety of data which has yet to produce benchmark numbers [A Bernard et al., J. Mosc. Phys. Soc. 8, 93-170 (1998)]. This present paper uses the Lee Model code [S Lee, http://www.plasmafocus.net (2012)], integrated with experimental measurements to provide the basis for reference numbers and the scaling of deuteron beams versus stored energy E{sub 0}. The ion number fluence (ions m{sup -2}) and energy fluence (J m{sup -2}) computed as 2.4-7.8 Multiplication-Sign 10{sup 20} and 2.2-33 Multiplication-Sign 10{sup 6}, respectively, are found to be independent of E{sub 0} from 0.4 to 486 kJ. Typical inductance machines (33-55 nH) produce 1.2-2 Multiplication-Sign 10{sup 15} ions per kJ carrying 1.3%-4% E{sub 0} at mean ion energy 50-205 keV, dropping to 0.6 Multiplication-Sign 10{sup 15} ions per kJ carrying 0.7% E{sub 0} for the high inductance INTI PF.

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

2012-11-15T23:59:59.000Z

224

Development of long-lived thick carbon stripper foils for high energy heavy ion accelerators by a heavy ion beam sputtering method  

Science Conference Proceedings (OSTI)

In the past decade, we have developed extremely long-lived carbon stripper foils of 1-50 {mu}g/cm{sup 2} thickness prepared by a heavy ion beam sputtering method. These foils were mainly used for low energy heavy ion beams. Recently, high energy negative Hydrogen and heavy ion accelerators have started to use carbon stripper foils of over 100 {mu}g/cm{sup 2} in thickness. However, the heavy ion beam sputtering method was unsuccessful in production of foils thicker than about 50 {mu}g/cm{sup 2} because of the collapse of carbon particle build-up from substrates during the sputtering process. The reproduction probability of the foils was less than 25%, and most of them had surface defects. However, these defects were successfully eliminated by introducing higher beam energies of sputtering ions and a substrate heater during the sputtering process. In this report we describe a highly reproducible method for making thick carbon stripper foils by a heavy ion beam sputtering with a Krypton ion beam.

Muto, Hideshi [Center of General Education, Tokyo University of Science, Suwa, 5000-1 Toyohira, Chino Nagano 391-0292 (Japan); Ohshiro, Yukimitsu [Center for Nuclear Study, School of Science, University of Tokyo, 2-1 Hirosawa, Riken Campus, Wako Saitama 351-0198 (Japan); Kawasaki, Katsunori [Van de Graaff Laboratory, Department of Physics, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro Tokyo 152-8551 (Japan); Oyaizu, Michihiro [Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba Ibaraki 305-0801 (Japan); Hattori, Toshiyuki [Heavy Ion Cancer Therapy Center, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage Chiba 263-855 (Japan)

2013-04-19T23:59:59.000Z

225

Carbon ion beam focusing using laser irradiated heated diamond hemispherical shells  

DOE Green Energy (OSTI)

Experiments preformed at the Los Alamos National Laboratory's Trident Laser Facility were conducted to observe the acceleration and focusing of carbon ions via the TNSA mechanism using hemispherical diamond targets. Trident is a 200TW class laser system with 80J of 1 {micro}m, short-pulse light delivered in 0.5ps, with a peak intensity of 5 x 10{sup 20} W/cm{sup 2}. Targets where Chemical Vapor Deposition (CVD) diamonds formed into hemispheres with a radius of curvature of 400{micro}m and a thickness of 5{micro}m. The accelerated ions from the hemisphere were diagnosed by imaging the shadow of a witness copper mesh grid located 2mm behind the target onto a film pack located 5cm behind the target. Ray tracing was used to determine the location of the ion focal spot. The TNSA mechanism favorably accelerates hydrogen found in and on the targets. To make the carbon beam detectable, targets were first heated to several hundred degrees Celsius using a CW, 532nm, 8W laser. Imaging of the carbon beam was accomplished via an auto-radiograph of a nuclear activated lithium fluoride window in the first layer of the film pack. The focus of the carbon ion beam was determined to be located 630 {+-} 110 {micro}m from the vertex of the hemisphere.

Offermann, Dustin T [Los Alamos National Laboratory; Flippo, Kirk A [Los Alamos National Laboratory; Gaillard, Sandrine A [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

226

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

SciTech Connect

A 130 keV injector is developed for the NDCX-II facility. It consists of a 10.9 cm diameter lithium doped alumina-silicate ion source heated to {approx}1300 C and 3 electrodes. Other components include a segmented Rogowski coil for current and beam position monitoring, a gate valve, pumping ports, a focusing solenoid, a steering coil and space for inspection and maintenance access. Significant design challenges including managing the 3-4 kW of power dissipation from the source heater, temperature uniformity across the emitter surface, quick access for frequent ion source replacement, mechanical alignment with tight tolerance, and structural stabilization of the cantilevered 27-inch OD graded HV ceramic column. The injector fabrication is scheduled to complete by May 2011, and assembly and installation is scheduled to complete by the beginning of July. The Neutralized Drift Compression eXperiment (NDCX-II) is for the study of high energy density physics and inertial fusion energy research utilizing a lithium ion (Li+) beam with a current of 93 mA and a pulse length of 500 ns (compressed to 1 ns at the target). The injector is one of the most complicated sections of the NDCX-II accelerator demanding significant design and fabrication resources. It needs to accommodate a relatively large ion source (10.9 cm), a high heat load (3-4 kW) and specific beam optics developed from the physics model. Some specific design challenges are noted in this paper.

Takakuwa, J.

2011-03-01T23:59:59.000Z

227

Ion beam surface treatment: A new capability for rapid melt and resolidification of surfaces  

Science Conference Proceedings (OSTI)

The emerging capability to produce high average power (5--250 kW) pulsed ion beams at 0.2--2 MeV energies is enabling us to develop a new, commercial-scale thermal surface treatment technology called Ion Beam Surface Treatment (IBEST). This technique uses high energy, pulsed ({le}100 ns) ion beams to directly deposit energy in the top 2--20 micrometers of the surface of any material. Depth of treatment is controllable by varying the ion energy and species. Deposition of the energy with short pulses in a thin surface layer allows melting of the layer with relatively small energies and allows rapid cooling of the melted layer by thermal diffusion into the underlying substrate. Typical cooling rates of this process (10{sup 9}10{sup 10} K/sec) cause rapid resolidification, resulting in production of non-equilibrium microstructures (nano-crystalline and metastable phases) that have significantly improved corrosion, wear, and hardness properties. We have conducted IBEST feasibility experiments with results confirming surface hardening, nanocrystaline grain formation, metal surface polishing, controlled melt of ceramic surfaces, and surface cleaning.

Stinnett, R.W.; McIntyre, D.C.; Buchheit, R.G. [Sandia National Labs., Albuquerque, NM (United States); Greenly, J.B.; Thompson, M.O. [Cornell Univ., Ithaca, NY (United States)

1994-04-01T23:59:59.000Z

228

A very low energy compact electron beam ion trap for spectroscopic research in Shanghai  

Science Conference Proceedings (OSTI)

In this paper, a new compact low energy electron beam ion trap, SH-PermEBIT, is reported. This electron beam ion trap (EBIT) can operate in the electron energy range of 60-5000 eV, with a current density of up to 100 A/cm{sup 2}. The low energy limit of this machine sets the record among the reported works so far. The magnetic field in the central drift tube region of this EBIT is around 0.5 T, produced by permanent magnets and soft iron. The design of this EBIT allows adjustment of the electron gun's axial position in the fringe field of the central magnetic field. This turned out to be very important for optimizing the magnetic field in the region of the electron gun and particularly important for low electron beam energy operation, since the magnetic field strength is not tunable with permanent magnets. In this work, transmission of the electron beam as well as the upper limit of the electron beam width under several conditions are measured. Spectral results from test operation of this EBIT at the electron energies of 60, 315, 2800, and 4100 eV are also reported.

Xiao, J.; Fei, Z.; Yang, Y.; Jin, X.; Lu, D.; Shen, Y.; Hutton, R.; Zou, Y. [The Key lab of Applied Ion Beam Physics, Ministry of Education, Shanghai (China); Shanghai EBIT lab, Institute of Modern Physics, Fudan University, Shanghai (China); Liljeby, L. [Manne Siegbahn Laboratory, Stockholm University, Stockholm (Sweden)

2012-01-15T23:59:59.000Z

229

Collective Focusing of Intense Ion Beam Pulses for High-energy Density Physics Applications  

SciTech Connect

The collective focusing concept in which a weak magnetic lens provides strong focusing of an intense ion beam pulse carrying a neutralizing electron background is investigated by making use of advanced particle-in-cell simulations and reduced analytical models. The original analysis by Robertson Phys. Rev. Lett. 48, 149 (1982) is extended to the parameter regimes of particular importance for several high-energy density physics applications. The present paper investigates (1) the effects of non-neutral collective focusing in a moderately strong magnetic field; (2) the diamagnetic effects leading to suppression of the applied magnetic field due to the presence of the beam pulse; and (3) the influence of a finite-radius conducting wall surrounding the beam cross-section on beam neutralization. In addition, it is demonstrated that the use of the collective focusing lens can significantly simplify the technical realization of the final focusing of ion beam pulses in the Neutralized Drift Compression Experiment-I (NDCX-I) , and the conceptual designs of possible experiments on NDCX-I are investigated by making use of advanced numerical simulations. 2011 American Institute of Physics

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

2011-04-27T23:59:59.000Z

230

Z-petawatt driven ion beam radiography development.  

SciTech Connect

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.

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

2013-09-01T23:59:59.000Z

231

Metal etching with reactive gas cluster ion beams using pickup cell  

Science Conference Proceedings (OSTI)

Mixed gas cluster ion beams were formed using pickup cell for metal etching. O{sub 2} neutral clusters pick up acetic acid and formed mixed cluster beam. By using O{sub 2}-GCIB with acetic acid, enhancement of Cu etching was observed. Because of dense energy deposition by GCIB, etching of Cu proceeds by CuO formation, enhancement of chemical reaction with acetic acid and desorption of etching products. Surface roughening was not observed on poly crystalline Cu because of the small dependence of etching rate on crystal orientation. Halogen free and low-temperature metal etching with GCIB using pickup cell is possible.

Toyoda, Noriaki; Yamada, Isao [Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeij, Hyogo, 671-2280 (Japan)

2012-11-06T23:59:59.000Z

232

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

Science Conference Proceedings (OSTI)

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

Kraus, W.; Fantz, U.; Franzen, P.; Froeschle, M.; Heinemann, B.; Riedl, R.; Wuenderlich, D. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, 85748 Garching (Germany)

2012-02-15T23:59:59.000Z

233

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

E-Print Network (OSTI)

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

Bret, Antoine; Tahir, Naeem

2012-01-01T23:59:59.000Z

234

Measurement of ion beam profiles in a superconducting linac with a laser wire  

Science Conference Proceedings (OSTI)

A laser wire ion beam profile monitor system has been developed at the Spallation Neutron Source accelerator complex. The laser wire system uses a single laser source to measure the horizontal and vertical profiles of a pulsed hydrogen ion (H{sup -}) beam along a 230 m long superconducting linac, which accelerates H{sup -} from 200 MeV to 1 GeV. In this paper, we describe the laser optics requirement for the system, the performance of the profile measurement, and the effects of laser parameters on the measurement reliability. The result provides a practical guideline for the development of a large-scale, operational, laser-based diagnostics in accelerator facilities.

Liu Yun; Long, Cary; Peters, Charles; Aleksandrov, Alexander

2010-12-10T23:59:59.000Z

235

Beam purification by photodetachment (invited)  

Science Conference Proceedings (OSTI)

Ion beam purity is of crucial importance to many basic and applied studies in nuclear science. Selective photodetachment has been proposed to suppress unwanted species in negative ion beams while preserving the intensity of the species of interest. A highly efficient technique based on photodetachment in a gas-filled radio frequency quadrupole ion cooler has been demonstrated. In off-line experiments with stable ions, up to 10{sup 4} times suppression of the isobar contaminants in a number of interesting radioactive negative ion beams has been demonstrated. For selected species, this technique promises new experimental possibilities in studies on exotic nuclei, accelerator mass spectrometry, and fundamental properties of negative atomic and molecular ions.

Liu, Y.; Beene, J. R.; Galindo-Uribarri, A.; Havener, C. C. [Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Andersson, P.; Forstner, O. [Vera Laboratory, Fakultaet fuer Physik, Universitaet Wien, AT-1090 Wien (Austria); Gottwald, T.; Wendt, K. [Institute of Physics, Johannes Gutenberg-University Mainz, D-55099 Mainz (Germany); Hanstorp, D.; Lindahl, A. O. [Department of Physics, University of Gothenburg, SE-412 96 Gothenburg (Sweden)

2012-02-15T23:59:59.000Z

236

Self-proton/ion radiography of laser-produced proton/ion beam from thin foil targets  

Science Conference Proceedings (OSTI)

Protons and multicharged ions generated from high-intensity laser interactions with thin foil targets have been studied with a 100 TW laser system. Protons/ions with energies up to 10 MeV are accelerated either from the front or the rear surface of the target material. We have observed for the first time that the protons/ions accelerated from the front surface of the target, in a direction opposite to the laser propagation direction, are turned around and pulled back to the rear surface, in the laser propagation direction. This proton/ion beam is able to create a self-radiograph of the target and glass stalk holding the target itself recorded through the radiochromic film stack. This unique result indicates strong long-living (ns time scale) magnetic fields present in the laser-produced plasma, which are extremely important in energy transport during the intense laser irradiation. The magnetic field from laser main pulse expands rapidly in the preformed plasma to rotate the laser produced protons. Radiation hydrodynamic simulations and ray tracing found that the magnetic field created by the amplified spontaneous emission prepulse is not sufficient to explain the particle trajectories, but the additional field created by the main pulse interaction estimated from particle-in-cell simulation is able to change the particle trajectories.

Paudel, Y.; Renard-Le Galloudec, N.; Kantsyrev, V. L.; Safronova, A. S.; Shrestha, I.; Osborne, G. C.; Shlyaptseva, V. V.; Sentoku, Y. [Physics Department, University of Nevada, Reno, Nevada 89557 (United States); Nicolai, Ph.; D'Humieres, E. [CELIA, Universite de Bordeaux-CNRS-CEA, 33405 Talence (France); Faenov, A.Ya. [Joint Institute for High Temperature, Russian Academy of Science, Izhirskaya Street, Moscow (Russian Federation) and Quantum Beam Science Directorate, Japan Atomic Energy Agency, Kyoto 619-0215 (Japan)

2012-12-15T23:59:59.000Z

237

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

Science Conference Proceedings (OSTI)

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

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

2012-07-15T23:59:59.000Z

238

Simple and inexpensive time-of-flight charge-to-mass analyzer for ion beam source characterization  

SciTech Connect

We describe the design, electronics, and test results of a simple and low-cost time-of-flight ion charge-to-mass analyzer that is suitable for ion source characterization. The method selects a short-time sample of the beam whose charge-to-mass composition is then separated according to ion velocity and detected by a remote Faraday cup. The analyzer is a detachable device that has been used for rapid analysis of charge-to-mass composition of ion beams accelerated by voltages of up to about 100 kV.

Gushenets, V. I.; Nikolaev, A. G.; Oks, E. M.; Vintizenko, L. G.; Yushkov, G. Yu.; Oztarhan, A.; Brown, I. G. [High Current Electronics Institute, Russian Academy of Sciences, 2/3 Akademichesky Avenue, Tomsk 634055 (Russian Federation); Ege University, Bornova-Izmir 35100 (Turkey); Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

2006-06-15T23:59:59.000Z

239

Investigation of aspect ratio of hole drilling from micro to nanoscale via focused ion beam fine milling  

E-Print Network (OSTI)

Holes with different sizes from microscale to nanoscale were directly fabricated by focused ion beam (FIB) milling in this paper. Maximum aspect ratio of the fabricated holes can be 5:1 for the hole with large size with ...

Fu, Yongqi

240

RECENT RESULTS OF FUSION INDUCED BY NEUTRON-RICH RADIOACTIVE BEAMS STUDIED AT HRIBF  

Science Conference Proceedings (OSTI)

The reaccelerated fission-fragment beams at HRIBF provide a unique opportunity for studying the mechanisms of fusion involving nuclei with large neutron excess. The fusion excitation functions for neutron-rich ra- dioactive 132Sn incident on 40Ca and 58Ni targets have been measured to explore the role of transfer couplings in sub-barrier fusion enhancement. Evaporation residue cross sections for 124,126,127,128Sn+64Ni were measured to study the dependence of fusion probability on neutron excess.

Liang, J Felix [ORNL] [ORNL

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
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to obtain the most current and comprehensive results.


241

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

SciTech Connect

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

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

2013-01-01T23:59:59.000Z

242

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

SciTech Connect

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.

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

2012-05-20T23:59:59.000Z

243

Collisional stochastic ripple diffusion of alpha particles and beam ions on TFTR  

Science Conference Proceedings (OSTI)

Predictions for ripple loss of fast ions from TFTR are investigated with a guiding center code including both collisional and ripple effects. A synergistic enhancement of fast ion diffusion is found for toroidal field ripple with collisions. The total loss is calculated to be roughly twice the sum of ripple and collisional losses calculated separately. Discrepancies between measurements and calculations of plasma beta at low current and large major radius are resolved when both effects are included for neutral beam ions. A 20--30% reduction in alpha particle heating is predicted for q{sub a} = 6--14, R = 2.6 m DT plasmas on TFTR due to first orbit and collisional stochastic ripple diffusion.

Redi, M.H.; Zarnstorff, M.C.; White, R.B.; Budny, R.V.; Janos, A.C.; Owens, D.K.; Schivell, J.F.; Scott, S.D.; Zweben, S.J.

1995-07-01T23:59:59.000Z

244

High intensity production of high and medium charge state uraniumand other heavy ion beams with VENUS  

SciTech Connect

The next generation, superconducting ECR ion source VENUS(Versatile ECR ion source for NUclear Science) started operation with 28GHzmicrowave heating in 2004. Since then it has produced world recordion beam intensities. For example, 2850 e mu A of O6+, 200 e mu A of U33+or U34+, and in respect to high charge state ions, 1 e mu A of Ar18+, 270e mu A of Ar16+, 28 e mu A of Xe35+ and 4.9 e mu A of U47+ have beenproduced. A brief overview of the latest developments leading to theserecord intensities is given and the production of high intensity uraniumbeams is discussed in more detail.

Leitner, Daniela; Galloway, Michelle L.; Loew, Timothy J.; Lyneis, Claude M.; Rodriguez, Ingrid Castro; Todd, Damon S.

2007-11-15T23:59:59.000Z

245

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

E-Print Network (OSTI)

and fusion Ranges given in table reflect options under study Table 4.1, page 43 of an HIF White Paper.E. Coleman et al., in Proc. of the 2007 Particle Accelerator Conf., Albuquerque, NM, 2007(IEEE catalog# 07CH-see http://videos.komando.com/2008/08/19/water-painting/]. #12;12/7/08 The Heavy Ion Fusion Science Virtual

246

Production of radioactivity in local soil at AGS fast neutrino beam  

SciTech Connect

Brookhaven National Laboratory (BNL) has recently decided to construct a new neutrino production target station at the Alternating Gradient Synchrotron (AGS). To determine the environmental impact of this addition, a study is being conducted in the vicinity of the old target area to determine the radiological consequences of operating this experimental facility. Typical BNL soil samples were placed at two locations near an operating target: at right angles to the target and behind thick shielding close to the direction of the incident beam. These samples were used to determine radionuclide production and leaching information. A core was taken from beneath the concrete floor of the old target area and a monitoring well was installed down-gradient of the facility. Preliminary results from all areas of the study are presented along with estimates of the potential environmental impact of the old and new facilities. 9 figures.

Gollon, P.J.; Hauptmann, M.G.; McIntyre, K.; Miltenberger, R.; Naidu, J.

1984-01-01T23:59:59.000Z

247

Nuclear reactions with 11C and 14O radioactive ion beams  

E-Print Network (OSTI)

J. Szmider, Soviet Journal of Nuclear Physics 52 (1990) 408-Wapstra, and C. Thibault, Nuclear Physics A 729 Aus68, P.IEEE Transactions on Nuclear Science, Gal00, A. Galindo-

Guo, Fanqing

2004-01-01T23:59:59.000Z

248

Focused ion beam assisted three-dimensional rock imaging at submicron scale  

SciTech Connect

Computation of effective flow properties of fluids in porous media based on three dimensional (3D) pore structure information has become more successful in the last few years, due to both improvements in the input data and the network models. Computed X-ray microtomography has been successful in 3D pore imaging at micron scale, which is adequate for many sandstones. For other rocks of economic interest, such as chalk and diatomite, submicron resolution is needed in order to resolve the 3D-pore structure. To achieve submicron resolution, a new method of sample serial sectioning and imaging using Focused Ion Beam (FIB) technology has been developed and 3D pore images of the pore system for diatomite and chalk have been obtained. FIB was used in the milling of layers as wide as 50 micrometers and as thin as 100 nanometers by sputtering of atoms from the sample surface. The focused ion beam, consisting of gallium ions (Ga+) accelerated by potentials of up to 30 kV and currents up to 20,000 pA, yields very clean, flat surfaces in which the pore-grain boundaries appear in high contrast. No distortion of the pore boundaries due to the ion milling is apparent. After each milling step, as a new surface is exposed, an image of the surface is generated. Using secondary electrons or ions, resolutions as high as 10 nm can be obtained. Afterwards, the series of 2D images can be stacked in the computer and, using appropriate interpolation and surface rendering algorithms, the 3D pore structure is reconstructed.

Tomutsa, Liviu; Radmilovic, Velimir

2003-05-09T23:59:59.000Z

249

Surface Modification of AISI-4620 Steel With Intense Pulsed Ion Beams  

SciTech Connect

A 300-keV, 30-kA, 1-{micro}s intense beam of carbon, oxygen, and hydrogen ions is used for the surface treatment of AISI-4620 steel coupons, a common material used in automotive gear applications. The beam is extracted from a magnetically-insulated vacuum diode and deposited into the top 1 {micro}m of the target surface. The beam-solid interaction causes a rapid melt and resolidification with heating and cooling rates of up to 10{sup 10} K/sec. Treated surfaces are smoothed over 1-{micro}m scale-lengths, but are accompanied by 1-{micro}m diameter craters and larger-scale roughening over >=10 {micro}m, depending on beam fluence and number of pulses. Treated surfaces are up to 1.8 x harder with no discernible change in modulus over depths of 1 {micro}m or more Qualitative improvements in the wear morphology of treated surfaces are reported.

Rej, D.J.; Davis, H.A.; Nastasi, M.; Olson, J.C.; Peterson, E.J.; Reiswig, R.D.; Walter, K.C.; Stinnett, R.W.; Remnev, G.E.; Struts, V.K.

1996-09-01T23:59:59.000Z

250

A QUEST FOR SYSTEM FRIENDLINESS WITH THE SNS ION BEAM BUNCH SHAPE MONITOR  

Science Conference Proceedings (OSTI)

A new system for measuring the SNS ion beam longitudinal profile was recently upgraded to operational status. The hardware for this device was developed and delivered by Institute of Nuclear Research to the SNS as a part of its initial construction. The supplied LabVIEW user interface software was intended for proof-of-operation and initial setup of the instrument. While satisfactory for this, it was tedious to use in a practical context and lacked any form of interface to the SNS EPICS based control system. This paper will describe the software features added to make this instrument both easily tunable to the prevalent beam conditions by system engineers and easily usable by accelerator physicists only interested in its output data.

Dickson, Richard W [ORNL; Aleksandrov, Alexander V [ORNL

2012-01-01T23:59:59.000Z

251

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

DOE Patents (OSTI)

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.

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

2008-03-04T23:59:59.000Z

252

On the origin of microcraters on the surface of ion beam bombardedplant cell walls  

SciTech Connect

Ion bombardment of plant and bacterial cellular material has recently been used as a tool for the transfer of exogenous DNA macromolecules into the cell interior region. The precise mechanism that leads to the transfer of macromolecules through the cell envelope is not yet clear, however it has been observed that the ion bombardment is accompanied by the formation of ''microcraters'' on the cell wall, and it is possible that these features provide channels for the macromolecule transfer. Thus the nature and origin of the microcraters is of importance to understanding the DNA transfer phenomenon as well as being of fundamental interest. We report here on some scanning electron microscope observations we have made of onion skin cells that have been subjected to electron beam bombardment of sufficiently high power density to damage the cell wall. The damage seen is much less than and different from the microcraters formed subsequent to ion bombardment. We speculate that the microcraters may originate from the explosive release of gas generated in the biomaterial by ion bombardment.

Salvadori, M.C.; Teixeira, F.S.; Brown, I.G.

2005-06-01T23:59:59.000Z

253

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

Science Conference Proceedings (OSTI)

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.

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

2012-05-15T23:59:59.000Z

254

Melting of Dense Hydrogen during Heavy Ion Beam-Driven Compression  

DOE Green Energy (OSTI)

Until now the thermodynamic and structural properties of hydrogen continue to be understood unsatisfactory. A number of complex high pressure phases at relatively low temperatures has been confirmed [1]. However, conclusive answers on the existence of a plasma phase transition, the dissociation of hydrogen molecules at high densities, the metallization in the solid, and the melting line for pressures above 70GPa are still missing. A particularly interesting behavior has been predicted for the melting line at high pressures where it has a maximum and its slope changes sign [2]. In Ref. [3], we have shown that these states can be created using cylindrical compression driven by heavy ion beams. Employing ab initio simulations [4] and experimental data, a new wide range equation of state for hydrogen was constructed [3]. This new hydrogen EOS combined with hydrodynamic simulations is then used to describe the compression of hydrogen in LAPLAS targets [5] driven by heavy ion beams to be generated at the FAIR. The results shown in Fig. 1 indicate that the melting line up to its maximum as well as the transition from molecular fluids to fully ionized plasmas can be tested. By carefully tuning the number of particles in the beam, the compression can be adjusted to yield states at the solid-liquid phase transition (compare panels (a) and (b) in Fig. 1). This allows one to test the shape of the melting line beyond its maximum. It was demonstrated [3] that x-ray scattering [6] can be used to distinguish between the molecular solid and liquid phases as well as the metallic states. Hydrodynamic simulations have also highlighted the importance of temperature diagnostics, as it is more sensitive to the EOS than the density based diagnostic methods. Different materials have been considered as absorber. Although lead might seem to be the natural choice, the simulations show that aluminium is also a feasible option if slightly less compression is sufficient. Moreover, aluminium offers further options for testing by x-ray scattering and, thus, might be favorable compared to lead drivers. In summary, valuable information on the properties of high-density hydrogen can be obtained by dynamic compression with heavy ion beams. The long standing questions of the plasma phase transition, melting, and metallization can be addressed. The calculated Jupiter isentrope shown in Fig. 1 indicates that such experiments would be also highly beneficial for the giant planet modeling.

Grinenko, A; Gericke, D O; Vorberger, J; Glenzer, S H

2009-03-02T23:59:59.000Z

255

Chemically-assisted ion-beam etching of (AIGa)As/GaAa: Lattice damage and removal by in-situ Cl2 treatment  

Science Conference Proceedings (OSTI)

Keywords: (ALGa)As/GaAs-SQW structures, chemically-assisted ion-beam etching, dry etching, in-situ Cl2 treatment, lattice damage, semiconductor

J. Daleiden; R. Kiefer; S. Klußmann; M. Kunzer; C. Manz; M. Wailher; J. Braunstein; G. Weimann

1999-02-01T23:59:59.000Z

256

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

E-Print Network (OSTI)

Physics of Magnetic Fusion Reactors, Rev. of Modern Physicsheavy ion beam driven fusion reactor study, Technical Reporta toroidally shaped fusion reactor (tokamak) such as shown

Prost, Lionel Robert

2007-01-01T23:59:59.000Z

257

Conformal growth of Mo/Si multilayers on grating substrates using collimated ion beam sputtering  

SciTech Connect

Deposition of multilayers on saw-tooth substrates is a key step in the fabrication of multilayer blazed gratings (MBG) for extreme ultraviolet and soft x-rays. Growth of the multilayers can be perturbed by shadowing effects caused by the highly corrugated surface of the substrates, which results in distortion of the multilayer stack structure and degradation of performance of MBGs. To minimize the shadowing effects, we used an ion-beam sputtering machine with a highly collimated atomic flux to deposit Mo/Si multilayers on saw-tooth substrates. The sputtering conditions were optimized by finding a balance between smoothening and roughening processes in order to minimize degradation of the groove profile in the course of deposition and at the same time to keep the interfaces of a multilayer stack smooth enough for high efficiency. An optimal value of energy of 200 eV for sputtering Kr{sup +} ions was found by deposition of test multilayers on flat substrates at a range of ion energies. Two saw-tooth substrates were deposited at energies of 200 eV and 700 eV for the sputtering ions. It was found that reduction of the ion energy improved the blazing performance of the MBG and resulted in a 40% gain in the diffraction efficiency due to better replication of the groove profile by the multilayer. As a result of the optimization performed, an absolute diffraction efficiency of 28.8% was achieved for the 2nd blaze order of the MBG with a groove density of 7350 lines/mm at a wavelength of 13.5 nm. Details of the growth behavior of the multilayers on flat and saw-tooth substrates are discussed in terms of the linear continuous model of film growth.

Voronov, D. L.; Cambie, R.; Dhuey, S.; Gullikson, E. M.; Warwick, T.; Yashchuk, V. V.; Padmore, H. A. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States); Gawlitza, P.; Braun, S. [Fraunhofer Institute for Material and Beam Technology, Winterbergstrasse 28, 01277 Dresden (Germany)

2012-05-01T23:59:59.000Z

258

Cratering behavior in single- and poly-crystalline copper irradiated by an intense pulsed ion beam  

Science Conference Proceedings (OSTI)

When treated with intense pulsed ion beams (IPIB), many materials exhibit increased wear resistance, fatigue life, and hardness. However, this treatment often results in cratering and roughening of the surface. In this work, high purity single crystal and polycrystalline copper samples were irradiated with pulses from an IPIB to gain insight into the causes of this cratering behavior. Samples were treated with 1,2,5, and 10 shots at 2 J/cm{sup 2} and 5 J/cm{sup 2} average energy fluence per shot. Shots were about 400 ns in duration and consisted of a mixture of carbon, hydrogen, and oxygen ions at 300 keV. It was found that the single crystal copper cratered far less than the polycrystalline copper at the lower energy fluence. At the higher energy fluence, cratering was replaced by other forms of surface damage, and the single crystal copper sustained less damage at all but the largest number of shots. Molten debris from the Lucite anode (the ion source) was removed and redeposited on the samples with each shot.

Wood, B.P.; Bitteker, L.J.; Waganaar, W.J. [Los Alamos National Lab., NM (United States). Plasma Physics Group; Perry, A.J. [A.I.M.S. Marketing, San Diego, CA (United States)

1998-12-31T23:59:59.000Z

259

Tracking of Ions Produced at Near Barrier Energies in Nuclear Reactions  

SciTech Connect

Examples of detectors, presently in use, for tracking products from nuclear reactions induced by radioactive ion beams are described. A new tracking detector is being designed to study the binary products from reactions induced by heavy neutron-rich radioactive ion beams on heavy neutron-rich target nuclei. The motivation for such studies and the features designed to accomplish this goal will be presented.

Shapira, Dan [ORNL

2010-01-01T23:59:59.000Z

260

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

SciTech Connect

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.

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

2012-02-15T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Secondary nuclear fragment beams for investigations of relativistic fragmentation of light radioactive nuclei using nuclear photoemulsion at Nuclotron  

E-Print Network (OSTI)

Slowly extracted relativistic beams of light nuclei and a beam transportation line net system constitute a good base for secondary nuclear beams forming at the LHE accelerator facility. A recent years activity in the field at the Laboratory is connected with a project on study light nuclei structure by means the emulsion technique [1,2]. The paper shortly summarizes results of the work.

Rukoyatkin, P A; Kukushkina, R I; Ramzhin, V N; Zarubin, P I

2012-01-01T23:59:59.000Z

262

Quantification of Dopant Concentrations in Diluted Magnetic Semiconductors using Ion Beam Techniques  

SciTech Connect

It has recently been demonstrated that magnetically doped TiO2 and SnO2 show ferromagnetism at room-temperature and Curie temperatures above room temperature. However, accurate knowledge of dopant concentrations is necessary to quantify magnetic moments in these materials. Rutherford Backscattering spectrometry (RBS) is one of the powerful techniques to quantify magnetic transition metal dopant concentrations in these materials. However, in some cases, the interference of RBS signals for different dopants and substrate elements in these materials makes analysis difficult. In this work, we demonstrate that particle induced x-ray emission (PIXE) can be successfully used to quantify the magnetic transition element dopants in several room temperature ferromagnetic materials synthesized using three different synthesis methods: oxygen plasma assisted molecular beam epitaxy, ion implantation and wet chemical methods.

Shutthanandan, V.; Thevuthasan, Suntharampillai; Droubay, Timothy; Kaspar, Tiffany C.; Punnoose, Alex; Hays, Jason; Chambers, Scott A.

2006-08-01T23:59:59.000Z

263

Assessment of Failure Mechanisms for Thermal Barrier Coatings by Photoluminescence, Electrochemical Impedance and Focused Ion Beam  

NLE Websites -- All DOE Office Websites (Extended Search)

H. Sohn, B. Jayaraj and V.H. Desai H. Sohn, B. Jayaraj and V.H. Desai SCIES Project 02- 01- SR103 DOE COOPERATIVE AGREEMENT DE-FC26-02NT41431 Tom J. George, Program Manager, DOE/NETL Richard Wenglarz, Manager of Research, SCIES Project Awarded (May 1, 2002, 36 Month Duration) $249,766 Total Contract Value ($208,228 DOE UTSR) Assessment of Failure Mechanisms for Thermal Barrier Coatings by Photoluminescence, Electrochemical Impedance and Focused Ion Beam YHS@UCF,10/17/05 Gas Turbine Needs: Reliable and Durable Thermal Barrier Coatings (TBCs) TBCs Provide Thermal Protection of Hot Components in Advanced Gas Turbine Engines Increase in Performance, Efficiency, Reliability and Maintainability. Reduction Life Cycle Costs. Reliable and Durable TBCs Needed as An Integral Part of Component Design.

264

Tailoring interfacial exchange coupling with low-energy ion beam bombardment: Tuning the interface roughness  

SciTech Connect

By ascertaining NiO surface roughness in a Ni{sub 80}Fe{sub 20}/NiO film system, we were able to correlate the effects of altered interface roughness from low-energy ion-beam bombardment of the NiO layer and the different thermal instabilities in the NiO nanocrystallites. From experiment and by modelling the temperature dependence of the exchange bias field and coercivity, we have found that reducing the interface roughness and changing the interface texture from an irregular to striped conformation enhanced the exchange coupling strength. Our results were in good agreement with recent simulations using the domain state model that incorporated interface mixing.

Lin, K.-W.; Shueh, C.; Huang, H.-R.; Hsu, H.-F. [Department of Materials Science and Engineering, National Chung Hsing University, Tiachung 402, Taiwan (China); Mirza, M.; Lierop, J. van [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada)

2012-03-19T23:59:59.000Z

265

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

Science Conference Proceedings (OSTI)

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.

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

2011-10-15T23:59:59.000Z

266

Giant magnetoresistance in ion beam deposited spin-valve films with specular enhancement  

Science Conference Proceedings (OSTI)

Three different techniques, natural oxidation, remote plasma oxidation and low energy ion beam oxidation, have been proved to be equally effective in forming nano-oxide layers (NOLs) in spin-valve films for specular enhancement of giant magnetoresistance (GMR) effect. GMR values over 12% have been routinely obtained in spin-valve films with NOL, corresponding to a 30% specular enhancement over those without NOL. The consistency and robustness of the oxidation processes has been demonstrated by a very large GMR value {similar_to}19% in a dual spin-valve film with the NOLs formed in both pinned layers, the oscillatory dependence of the interlayer coupling field on Cu layer thickness in specular enhanced spin-valve films and the uniform and repeatable film performance over 5 in. substrates. {copyright} 2001 American Institute of Physics.

Sant, S.; Mao, M.; Kools, J.; Koi, K.; Iwasaki, H.; Sahashi, M.

2001-06-01T23:59:59.000Z

267

Dynamics of Plasma-Surface Interactions using In-situ Ion Beam Analysis  

SciTech Connect

The overall goal of this proposal was to develop an innovative experimental facility that would allow for the measurement of real-time response of a material surface to plasma bombardment by employing in-situ high-energy ion beam analysis. This facility was successfully developed and deployed at U. Wisconsin-Madison and was named DIONISOS (Dynamics of IONic Implantation & Sputtering on Surfaces). There were several major highlights to the DIONISOS research which we will briefly highlight below. The full technical details of the DIONISOS development, deployment and research results are contained in the Appendices which contain several peer-reviewed publications and a PhD thesis devoted to DIONISOS. The DIONISOS results on deuterium retention in molybdenum were chosen as an invited talk at the 2008 International Conference on Plasma-Surface Interactions in Toledo, Spain.

D.G. Whyte

2009-07-16T23:59:59.000Z

268

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

SciTech Connect

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

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

2012-04-15T23:59:59.000Z

269

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

Science Conference Proceedings (OSTI)

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 ?s each. At this rate, the source lifetime was independent of the actual beam charge extracted due to the loss of neutral atoms at high temperature. The source lifetime increases with the amount of alumino-silicate coated on the emitting surface, and may also be further extended if the temperature is reduced between pulses.

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

2012-03-05T23:59:59.000Z

270

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

SciTech Connect

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.

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

2012-03-05T23:59:59.000Z

271

Observation of threshold energy and hysteresis in high current ion beam guiding and transmission through a micro-glass-capillary  

Science Conference Proceedings (OSTI)

The energy dependent guiding of high current density (0.1-3 A/m{sup 2}) argon ion beams through a micro-glass-capillary is studied. It is observed that ion transmission through the capillary takes place only if its energy is greater than the retarding potential barrier, which depends upon the amount of charge deposited on the capillary inner wall. Foremost evidence of the observation that the transmitted current exhibits hysteresis with ion energy is presented. Particle in cell simulations carried out by solving Poisson's and Newton's force equation self-consistently, agree reasonably well with the experimental results.

Paul, Samit; Jayakiran, A.; Bhattacharjee, Sudeep [Department of Physics, Indian Institute of Technology, Kanpur, Uttar Pradesh 208016 (India)

2012-11-26T23:59:59.000Z

272

Tilting of carbon encapsulated metallic nanocolumns in carbon-nickel nanocomposite films by ion beam assisted deposition  

Science Conference Proceedings (OSTI)

The influence of assisting low-energy ({approx}50-100 eV) ion irradiation effects on the morphology of C:Ni ({approx}15 at. %) nanocomposite films during ion beam assisted deposition (IBAD) is investigated. It is shown that IBAD promotes the columnar growth of carbon encapsulated metallic nanoparticles. The momentum transfer from assisting ions results in tilting of the columns in relation to the growing film surface. Complex secondary structures are obtained, in which a significant part of the columns grows under local epitaxy via the junction of sequentially deposited thin film fractions. The influence of such anisotropic film morphology on the optical properties is highlighted.

Krause, Matthias [Helmholtz-Zentrum Dresden-Rossendorf, PF-510119, 01314 Dresden (Germany); Technische Universitaet Dresden, D-01062 Dresden (Germany); Muecklich, Arndt; Zschornak, Matthias; Wintz, Sebastian; Gemming, Sibylle; Abrasonis, Gintautas [Helmholtz-Zentrum Dresden-Rossendorf, PF-510119, 01314 Dresden (Germany); Oates, Thomas W. H. [Leibniz-Institut fuer Analytische Wissenschaft, ISAS e.V., Albert-Einstein-Str. 9, 12489 Berlin (Germany); Luis Endrino, Jose [Surfaces and Coatings Department, Instituto de Ciencia de Materiales de Madrid, c/Sor Juana Ines de la Cruz 3, Cantoblanco, 28049 Madrid (Spain); Baehtz, Carsten; Shalimov, Artem [Helmholtz-Zentrum Dresden-Rossendorf, PF-510119, 01314 Dresden (Germany); Rossendorf Beamline, European Synchrotron Radiation Facility, F-38043 Grenoble (France)

2012-07-30T23:59:59.000Z

273

Pulsed ion beam methods for in situ characterization of diamond film deposition processes  

DOE Green Energy (OSTI)

Diamond and diamond-like carbon (DLC) have properties which in principle make them ideally suited to a wide variety of thin-film applications. Their widespread use as thin films, however, has been limited for a number of reasons related largely to the lack of understanding and control of the nucleation and growth processes. Real-time, in situ studies of the surface of the growing diamond film are experimentally difficult because these films are normally grown under a relatively high pressure of hydrogen, and conventional surface analytical methods require an ultrahigh vacuum environment. It is believed, however, that the presence of hydrogen during growth is necessary to stabilize the corrugated diamond surface structure and thereby prevent the formation of the graphitic phase. Pulsed ion beam-based analytical methods with differentially pumped ion sources and particle detectors are able to characterize the uppermost atomic layer of a film during, growth at ambient pressures 5-7 orders of magnitude higher than other surface-specific analytical methods. We describe here a system which has been developed for the purpose of determining the hydrogen concentration and bonding sites on diamond surfaces as a function of sample temperature and ambient hydrogen pressure under hot filament CVD growth conditions. It is demonstrated that as the hydrogen partial pressure increases, the saturation hydrogen coverage of the surface of a CVD diamond film increases, but that the saturation level depends on the atomic hydrogen concentration and substrate temperature.

Krauss, A.R.; Smentkowski, V.S.; Zuiker, C.D.; Gruen, D.M. [Argonne National Lab., IL (United States); Im, J. [Argonne National Lab., IL (United States)]|[Northwestern Univ., Evanston, IL (United States). Dept. of Materials Science and Engineering; Schultz, J.A.; Waters, K. [Ionwerks Corp., Houston, TX (United States); Chang, R.P.H. [Northwestern Univ., Evanston, IL (United States). Dept. of Materials Science and Engineering

1995-06-01T23:59:59.000Z

274

Extended calibration range for prompt photon emission in ion beam irradiation  

E-Print Network (OSTI)

Monitoring the dose delivered during proton and carbon ion therapy is still a matter of research. Among the possible solutions, several exploit the measurement of the single photon emission from nuclear decays induced by the irradiation. To fully characterize such emission the detectors need development, since the energy spectrum spans the range above the MeV that is not traditionally used in medical applications. On the other hand, a deeper understanding of the reactions involving gamma production is needed in order to improve the physic models of Monte Carlo codes, relevant for an accurate prediction of the prompt-gamma energy spectrum.This paper describes a calibration technique tailored for the range of energy of interest and reanalyzes the data of the interaction of a 80MeV/u fully stripped carbon ion beam with a Poly-methyl methacrylate target. By adopting the FLUKA simulation with the appropriate calibration and resolution a significant improvement in the agreement between data and simulation is report...

Bellini, F; Chin, M P W; Collamati, F; De Lucia, E; Faccini, R; Ferrari, A; Lanza, L; Mancini-Terraciano, C; Marafini, M; Mattei, I; Morganti, S; Ortega, P G; Patera, V; Piersanti, L; Russomando, A; Sala, P R; Sarti, A; Sciubba, A; Camillocci, E Solfaroli; Voena, C

2013-01-01T23:59:59.000Z

275

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

DOE Green Energy (OSTI)

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

Savas, S.E.

1980-09-01T23:59:59.000Z

276

Simultaneous Formation of Surface Ripples and Metallic Nanodots Induced by Phase Decomposition and Focused Ion Beam Patterning  

Science Conference Proceedings (OSTI)

We report the simultaneous formation of self-assembled surface ripples in Cd{sub 2}Nb{sub 2}O{sub 7} pyrochlore caused by focused ion beam (FIB) patterning and uniformly distributed metallic nanodots induced by phase decomposition under ion bombardment. The characteristic wavelength of the surface ripples is controllable from the nm to the sub-{micro}m scale. High-density Cd metallic nanoparticles, {approx} 5 nm, formed and the distribution of nanoparticles is consistent with the morphological characteristics of the ripple pattern. This approach provides a means of fabricating surface nanostructure with various patterns and a controllable particle size and distribution by combining ion beam-induced phase decomposition with high-precision FIB patterning.

Lian, Jie [University of Michigan; Zhou, Wei [Nanyang Technological University; Wei, Q.M. [University of Michigan; Wang, L. M. [University of Michigan; Boatner, Lynn A [ORNL; Ewing, Rodney C. [University of Michigan

2006-01-01T23:59:59.000Z

277

Focused ion beam patterned Fe thin films A study by selective area Stokes polarimetry and soft x-Ray microscopy  

Science Conference Proceedings (OSTI)

We demonstrate the potential to modify the magnetic behavior and structural properties of ferromagnetic thin films using focused ion beam 'direct-write' lithography. Patterns inspired by the split-ring resonators often used as components in meta-materials were defined upon 15 nm Fe films using a 30 keV Ga{sup +} focused ion beam at a dose of 2 x 10{sup 16} ions cm{sup -2}. Structural, chemical and magnetic changes to the Fe were studied using transmission soft X-ray microscopy at the ALS, Berkeley CA. X-ray absorption spectra showed a 23% reduction in the thickness of the film in the Ga irradiated areas, but no chemical change to the Fe was evident. X-ray images of the magnetic reversal process show domain wall pinning around the implanted areas, resulting in an overall increase in the coercivity of the film. Transmission electron microscopy showed significant grain growth in the implanted regions.

Cook, P. J.; Shen, T. H.; Grundy, P. J.; Im, M.-Y.; Fischer, P.; Morton, S. A.; Kilcoyne, A. L. D.

2010-11-14T23:59:59.000Z

278

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

SciTech Connect

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

Niu, Hongsen

1995-02-10T23:59:59.000Z

279

Ion and electron beam nanofabrication of the which-way double-slit experiment in a transmission electron microscope  

Science Conference Proceedings (OSTI)

We have realized a which-way experiment closely resembling the original Feynman's proposal exploiting focused ion beam milling to prepare two nanoslits and electron beam induced deposition to grow, selectively over one of them, electron transparent layers of low atomic number amorphous material to realize a which-way detector for high energy electrons. By carrying out the experiment in an electron microscope equipped with an energy filter, we show that the inelastic scattering of electron transmitted through amorphous layers of different thicknesses provides the control of the dissipative interaction process responsible for the localization phenomena which cancels out the interference effects.

Frabboni, Stefano [Department of Physics, University of Modena and Reggio Emilia and CNR-Institute of Nanoscience-S3, via G. Campi 213/a, 41100 Modena (Italy); Gazzadi, Gian Carlo [CNR-Institute of Nanoscience-S3, via G. Campi 213/a, 41100 Modena (Italy); Pozzi, Giulio [Department of Physics, University of Bologna, viale B. Pichat 6/2, 40127 Bologna (Italy)

2010-12-27T23:59:59.000Z

280

Sub microsecond notching of a negative hydrogen beam at low energy utilizing a magnetron ion source with a split extractor  

DOE Green Energy (OSTI)

A technique for sub-microsecond beam notching is being developed at 20 keV utilizing a Magnetron ion source with a slit extraction system and a split extractor. Each half of the extractor is treated as part of a 50 ohm transmission line which can be pulsed at {+-}700 volts creating a 1400 volt gradient. This system along with the associated electronics is electrically floated on top of a pulsed extraction voltage. A beam reduction of 95% has been observed at the end of the Fermilab 400 MeV Linac and 35% notching has recently been achieved in the Booster.

Moehs, Douglas; /Fermilab

2004-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
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281

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

SciTech Connect

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.

Groves, Jaes R [Los Alamos National Laboratory; De Paula, Raymond F [Los Alamos National Laboratory; Hayes, Garrett H [STANFORD UNIV.; Li, Joel B [STANFORD UNIV.; Hammond, Robert H [STANFORD UNIV.; Salleo, Alberto [STANFORD UNIV.; Clemens, Bruce M [STANFORD UNIV.

2010-01-01T23:59:59.000Z

282

Stark spectroscopy of a probe lithium beam excited with two dye lasers as a technique to study a high-power ion-beam diode  

SciTech Connect

A non-disturbing measurement of electric field distributions is a subject of special interest in plasma physics and high-voltage devices. In this paper we describe a diagnostic technique for remote sensing of electric fields via injection of a probe beam of lithium atoms and cascade excitation of resonance fluorescence with two broadband dye lasers. The fluorescence spectrum was recorded using a monochromator equipped with an optical multi-channel analyser. The magnitude of the local electric field was retrieved from the Stark-shifted components of the 3d-2plithium spectral line. The technique was applied to measurements of the electric field in the applied-B-field high-voltage diode of the 1 TW KALIF ion-beam accelerator.

Knyazev, B. A. [Budker Institute of Nuclear Physics SB RAS, 630090 Novosibirsk (Russian Federation); An, W.; Bluhm, H. [Karlsruhe Institute of Technology (KIT), Institute for Pulsed Power and Microwave Technology (IHM), D-76131 Karlsruhe (Germany)

2012-03-15T23:59:59.000Z

283

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

SciTech Connect

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.

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)

2012-07-15T23:59:59.000Z

284

Glass forming ability of the Mo-Pd system studied by thermodynamic modeling and ion beam mixing  

SciTech Connect

Glass forming ability/range of the Mo-Pd binary metal system was studied by thermodynamic calculations employing Miedema's model and ion beam mixing of multiple metal layers. The thermodynamic calculations predict a narrow composition range of 8-26 at% Pd, within which metallic glass formation is energetically favored, whereas the experimental results showed that ion beam mixing was able to synthesize metallic glasses within a composition range 13-30 at% Pd, which was well in accordance with the prediction. Besides, in the Mo{sub 70}Pd{sub 30} multilayered films, with varying the irradiation dose, a dual-phase metallic glass was formed, and it could be considered as an intermediate state. The possible mechanism for the formation of the metallic glasses was also discussed in terms of the atomic collision theory.

Ding, N.; Li, J. H.; Liu, B. X.

2011-07-01T23:59:59.000Z

285

Virtually distortion-free imaging system for large field, high resolution lithography using electrons, ions or other particle beams  

DOE Patents (OSTI)

Virtually distortion free large field high resolution imaging is performed using an imaging system which contains large field distortion or field curvature. A reticle is imaged in one direction through the optical system to form an encoded mask. The encoded mask is then imaged back through the imaging system onto a wafer positioned at the reticle position. Particle beams, including electrons, ions and neutral particles, may be used as well as electromagnetic radiation.

Hawryluk, A.M.; Ceglio, N.M.

1991-04-10T23:59:59.000Z

286

Virtually distortion-free imaging system for large field, high resolution lithography using electrons, ions or other particle beams  

DOE Patents (OSTI)

Virtually distortion free large field high resolution imaging is performed using an imaging system which contains large field distortion or field curvature. A reticle is imaged in one direction through the optical system to form an encoded mask. The encoded mask is then imaged back through the imaging system onto a wafer positioned at the reticle position. Particle beams, including electrons, ions and neutral particles, may be used as well as electromagnetic radiation.

Hawryluk, Andrew M. (Modesto, CA); Ceglio, Natale M. (Livermore, CA)

1993-01-01T23:59:59.000Z

287

Status of the ion sources developments for the Spiral2 project at GANIL  

SciTech Connect

The SPIRAL 2 facility is now under construction and will deliver either stable or radioactive ion beams. First tests of nickel beam production have been performed at GANIL with a new version of the large capacity oven, and a calcium beam has been produced on the heavy ion low energy beam transport line of SPIRAL 2, installed at LPSC Grenoble. For the production of radioactive beams, several target/ion-source systems (TISSs) are under development at GANIL as the 2.45 GHz electron cyclotron resonance ion source, the surface ionization source, and the oven prototype for heating the uranium carbide target up to 2000 deg. C. The existing test bench has been upgraded for these developments and a new one, dedicated for the validation of the TISS before mounting in the production module, is under design. Results and current status of these activities are presented.

Leherissier, P.; Bajeat, O.; Barue, C.; Canet, C.; Dubois, M.; Dupuis, M.; Flambard, J. L.; Frigot, R.; Jardin, P.; Leboucher, C.; Lemagnen, F.; Maunoury, L.; Osmond, B.; Pacquet, J. Y.; Pichard, A. [GANIL, Grand Accelerateur National d'Ions Lourds, CEA-DSM/CNRS-IN2P3, Bvd H. Becquerel, BP 55027 14076 Caen Cedex 5 (France); Thuillier, T. [LPSC, Universite Joseph Fourier Grenoble 1, CNRS/IN2P3, Institut Polytechnique de Grenoble, Grenoble (France); Peaucelle, C. [IPNL, Universite de Lyon, Universite de Lyon 1, CNRS/IN2P3, Villeurbanne (France)

2012-02-15T23:59:59.000Z

288

Status of the SNS H- ion source and low-energy beam transport system  

E-Print Network (OSTI)

Status of the SNS H - Ion Source and Low-Energy Beamto the Spallation Neutron Source (SNS)** Front End and theearly operating phases of SNS. The ion source was derived

Keller, R.; Thomae, R.; Stockli, M.; Welton, R.

2002-01-01T23:59:59.000Z

289

Beam energy tracking system on Optima XEx high energy ion implanter  

SciTech Connect

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.

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

2012-11-06T23:59:59.000Z

290

Ion production from solid state laser ion sources  

Science Conference Proceedings (OSTI)

Laser ion sources based on resonant excitation and ionization of atoms are well-established tools for selective and efficient production of radioactive ion beams. Recent developments are focused on the use of the state-of-the-art all solid-state laser systems. To date, 35 elements of the periodic table are available from laser ion sources based on tunable Ti:sapphire lasers. Recent progress in this field regarding the establishment of suitable optical excitation schemes for Ti:sapphire lasers are reported.

Gottwald, T.; Mattolat, C.; Raeder, S.; Wendt, K. [Institute for Physics, University of Mainz, Staudinger Weg 7, 55128 Mainz (Germany); Havener, C.; Liu, Y. [Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Lassen, J. [TRIUMF-ISAC Division, 4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3 (Canada); Rothe, S. [CERN, CH-1211 Geneve 23 (Switzerland)

2010-02-15T23:59:59.000Z

291

Work function measurements during plasma exposition at conditions relevant in negative ion sources for the ITER neutral beam injection  

SciTech Connect

Cesium seeded sources for surface generated negative hydrogen ions are major components of neutral beam injection systems in future large-scale fusion experiments such as ITER. The stability and delivered current density depend highly on the work function during vacuum and plasma phases of the ion source. One of the most important quantities that affect the source performance is the work function. A modified photocurrent method was developed to measure the temporal behavior of the work function during and after cesium evaporation. The investigation of cesium exposed Mo and MoLa samples under ITER negative hydrogen ion based neutral beam injection relevant surface and plasma conditions showed the influence of impurities which result in a fast degradation when the plasma exposure or the cesium flux onto the sample is stopped. A minimum work function close to that of bulk cesium was obtained under the influence of the plasma exposition, while a significantly higher work function was observed under ITER-like vacuum conditions.

Gutser, R. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, 85748 Garching (Germany); Wimmer, C. [Lst. f. Experimentelle Plasmaphysik, Universitaet Augsburg, 86135 Augsburg (Germany); Fantz, U. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, 85748 Garching (Germany); Lst. f. Experimentelle Plasmaphysik, Universitaet Augsburg, 86135 Augsburg (Germany)

2011-02-15T23:59:59.000Z

292

Erosion of a-C:D Thin Films by Low Energy D+, D2+, and D3+ Ion Beam Irradiation  

Science Conference Proceedings (OSTI)

We report measurements of total C sputtering yields for room temperature a-C:D thin films irrradiated by equal velocity D{sup +}, D{sub 2}{sup +}, and D{sub 3}{sup +} beams in the energy range 30-200 eV/D. The C sputtering yields were deduced from crater volumes determined from 2-D ellipsometry scans, the known thin film C density, and the measured total number of incident D particles during the beam exposures. While our results for incident D{sub 3}{sup +} ions are in good agreement with mass loss measurements for D{sub 3}{sup +}, our results for D{sub 2}{sup +} and D{sup +} incident ions fall systematically below the D{sub 3}{sup +} results, indicating a significant molecular size effect. A molecular size effect has been previously found for CD{sub 4} production during low energy impact of same velocity D{sup +}, D{sub 2}{sup +}, and D{sub 3}{sup +} ions incident on ATJ graphite, which, however, was smaller in magnitude. The ellipsometry-based total C sputtering yields are compared with recently deduced total C production yields based on a mass spectroscopy approach.

Meyer, Fred W [ORNL; Harris, Peter R [ORNL; Zhang, Hengda [ORNL; Jacob, W. [Max-Planck-Institut fur Plasmaphysik, EURATOM Association, Garching, Germany; Schwarz-Selinger, T. [Max-Planck-Institut fur Plasmaphysik, EURATOM Association, Garching, Germany; Von Toussaint, U. [Max-Planck-Institut fur Plasmaphysik, EURATOM Association, Garching, Germany

2011-01-01T23:59:59.000Z

293

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

SciTech Connect

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.

Armijo, Julien

2006-10-01T23:59:59.000Z

294

Time evolution of the luminosity of colliding heavy-ion beams in BNL Relativistic Heavy Ion Collider and CERN Large Hadron Collider  

E-Print Network (OSTI)

We have studied the time evolution of the heavy ion luminosity and bunch intensities in the Relativistic Heavy Ion Collider (RHIC), at BNL, and in the Large Hadron Collider (LHC), at CERN. First, we present measurements from a large number of RHIC stores (from Run 7), colliding 100 GeV/nucleon Au beams without stochastic cooling. These are compared with two different calculation methods. The first is a simulation based on multi-particle tracking taking into account collisions, intrabeam scattering, radiation damping, and synchrotron and betatron motion. In the second, faster, method, a system of ordinary differential equations with terms describing the corresponding effects on emittances and bunch populations is solved numerically. Results of the tracking method agree very well with the RHIC data. With the faster method, significant discrepancies are found since the losses of particles diffusing out of the RF bucket due to intrabeam scattering are not modeled accurately enough. Finally, we use both methods to make predictions of the time evolution of the future Pb beams in the LHC at injection and collision energy. For this machine, the two methods agree well.

R. Bruce; M. Blaskiewicz; W. Fischer; J. M. Jowett

2010-09-08T23:59:59.000Z

295

Simulation study on light ions identification methods for carbon beams from 95 to 400 MeV/A  

E-Print Network (OSTI)

Monte Carlo simulations have been performed in order to evaluate the efficiencies of several light ions identification techniques. The detection system was composed with layers of scintillating material to measure either the deposited energy or the time-of-flight of ions produced by nuclear reactions between 12C projectiles and a PMMA target. Well known techniques such as (DELTA) E--Range, (DELTA) E--E--ToF and (DELTA)E--E are presented and their particle identification efficiencies are compared one to another regarding the generated charge and mass of the particle to be identified. The simulations allowed to change the beam energy matching the ones proposed in an hadron therapy facility, namely from 95 to 400 MeV/A.

S. Salvador; M. Labalme; J. M. Fontbonne; J. Dudouet; J. Colin; D. Cussol

2013-10-01T23:59:59.000Z

296

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

SciTech Connect

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

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

2009-08-01T23:59:59.000Z

297

Detection of Ionizing Radiation by Plasma-Panel Sensors: Cosmic Muons, Ion Beams, and Cancer Therapy  

Science Conference Proceedings (OSTI)

The plasma panel sensor is an ionizing photon and particle radiation detector derived from PDP technology with high gain and nanosecond response. Experimental results in detecting cosmic ray muons and beta particles from radioactive sources are described along with applications including high energy and nuclear physics, homeland security and cancer therapeutics.

Friedman, Dr. Peter S. [Integrated Sensors, LLC; Ferretti, Claudio [University of Michigan; Ball, Robert [University of Michigan; Beene, James R [ORNL; Ben Moshe, M. [Tel Aviv University; Benhammou, Yan [Tel Aviv University; Chapman, J. Wehrley [University of Michigan; Levin, Daniel S. [University of Michigan; Silver, Yiftah [Tel Aviv University; Weaverdyck, Curtis [University of Michigan; Zhou, Bing [University of Michigan; Etzion, E [Tel Aviv University; Moshe, M. [Tel Aviv University; Bentefour, E [Ion Beam Applications

2012-01-01T23:59:59.000Z

298

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

E-Print Network (OSTI)

beam in a four solenoid lattice J.E. Coleman Department ofbeam in a two-solenoid lattice. Initial experiments showed aadded to the two-solenoid lattice in order to study electron

2008-01-01T23:59:59.000Z

299

Ion Beam Induced Charge Collection (IBICC) from Integrated Circuit Test Structures Using a 10 MeV Carbon Microbeam  

Science Conference Proceedings (OSTI)

As future sizes of Integrated Circuits (ICs) continue to shrink the sensitivity of these devices, particularly SRAMs and DRAMs, to natural radiation is increasing. In this paper, the Ion Beam Induced Charge Collection (IBICC) technique is utilized to simulate neutron-induced Si recoil effects in ICS. The IBICC measurements, conducted at the Sandia National Laboratories employed a 10 MeV carbon microbeam with 1pm diameter spot to scan test structures on specifically designed ICS. With the aid of layout information, an analysis of the charge collection efficiency from different test areas is presented. In the present work a 10 MeV Carbon high-resolution microbeam was used to demonstrate the differential charge collection efficiency in ICS with the aid of the IC design Information. When ions strike outside the FET, the charge was only measured on the outer ring, and decreased with strike distance from this diode. When ions directly strike the inner and ring diodes, the collected charge was localized to these diodes. The charge for ions striking the gate region was shared between the inner and ring diodes. I The IBICC measurements directly confirmed the interpretations made in the earlier work.

Aton, T.J.; Doyle, B.L.; Duggan, J.L.; El Bouanani, M.; Guo, B.N.; McDaniel, F.D.; Renfrow, S.N.; Walsh, D.S.

1998-11-18T23:59:59.000Z

300

Chromium Grain-boundary Segregation and Effect of Ion Beam Cleaning on Fe-Ni-Cr Alloys  

SciTech Connect

The grain boundaries play important role to control the mechanical strength of ternary alloys. From spacecrafts to naval vessels to nuclear reactors, stress corrosion cracking, brittleness, oxidation mostly originates at the grain boundaries and cause long term structural stability problems in most of the metallic structures [1]. Fe-Ni-Cr based ternary metal alloys have been widely studied for more than fifty years [2, 3]. Despite of vast amount of research, chromium diffusion in stainless steel or other Ni-Fe-Cr based ternary alloys is still an open scientific problem with challenges in structural stability and corrosion resistance [4]. Particularly, austenite Fe-Ni-Cr is looked upon favorably in space and jet engine industry for their improved resistance to stress corrosion cracking [5]. In solid oxide fuel cells (SOFC), Ni-alloys are frequently used as interconnects and seals [6]. In this communication, simultaneous energy dispersive spectroscopy (EDS) and electron backscatter diffraction (EBSD) mapping is utilized to study chemical and structural aspects of chromium segregation in Fe-Ni-Cr alloy. A focused Ga-ion beam is also utilized to study the effect of ion beam cleaning on EBSD image quality (IQ) and inverse pole figure (IPF) maps of Fe-Ni-Cr alloy.

Saraf, Laxmikant V.

2011-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Whistler Wave Excitation and Effects of Self-Focusing on Ion Beam Propagation through a Background Plasma along a Solenoidal Magnetic Field  

SciTech Connect

This paper extends studies of ion beam transport through a background plasma along a solenoidal magnetic field [I. Kaganovich et al., Phys. Plasmas 15, 103108 (2008)] to the important regime of moderate magnetic field strength satisfying ?ce > 2?b?pe . Here, ?ce and ? pe are the electron cyclotron frequency and electron plasma frequency, respectively, and ?b = vb/ c is the directed ion beam velocity normalized to the speed of light. The electromagnetic field perturbations excited by the ion beam pulse in this regime are calculated analytically, and verified by comparison with the numerical simulations. The degrees of beam charge neutralization and current neutralization are estimated, and the transverse component of the Lorentz force associated with the excited electromagnetic field is calculated. It is found that the plasma response to the ion beam pulse is significantly different depending on whether the value of the solenoidal magnetic field is below or above the threshold value specified by ? cr ce = 2?b?pe, and corresponding to the resonant excitation of large-amplitude whistler waves. The use of intense whistler wave excitations for diagnostic purposes is also discussed.

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

2010-02-02T23:59:59.000Z

302

Measurements of the intercombination and forbidden lines from helium-like ions in Tokamaks and Electron Beam Ion Traps  

SciTech Connect

The paper reviews the results from tokamak experiments for the line ratios x/w, y/w, and z/w from helium-like ions with Z in the range from 14 to 28. With exception of the DITE experiments, where these line ratios were found to be in agreement with theoretical predictions, all other tokamak experiments yielded values that were significantly larger than predicted. The reasons for these discrepancies are not yet understood. It is possible that radial profile effects were not properly taken into account in the majority of the tokamak experiments. The paper also gives a short historical review of the X-ray diagnostic developments and also presents very recent data from a new type of X-ray imaging crystal spectrometer, which records spatially resolved spectra with a spatial resolution of about 1 cm in the plasma. These new data can be Abel inverted, so that it will be possible to determine line ratios at each radial position in the plasma. Effects of radial profiles, which may have affected the chord-integrated measurements of the past, will thus be eliminated in the future.

Bitter, M; Hill, K W; von Goeler, S; Stodiek, W; Beiersdorfer, P; Rice, J E; Ince-Cushman, A

2007-08-22T23:59:59.000Z

303

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

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.

Drentje, A.G.; Muramatsu, M.; Kitagawa, A. [K.V.I., University of Groningen, Zernikelaan 25, 9747AA Groningen (Netherlands); National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan)

2006-03-15T23:59:59.000Z

304

Beam instrumentation for an ISOL test stand  

SciTech Connect

TRIUMF is constructing a test bed for the first stages of the proposed TISAC accelerated radioactive beam facility. The authors will present the requirements for the diagnostic system for this test stand and describe the design and development work underway. Scintillators, beamstops and a Faraday Cup have been tested using stable, mass analyzed, 12 keV beams of ions from mass 14 to 132. The design of a linear drive, with 10 {micro}m resolution, for scanning wires and slits has begun.

Mackenzie, G.H.; Dombsky, M.; Rawnsley, W.; Stanford, G.; Yin, Y. [TRIUMF, Vancouver, British Columbia (Canada); Novikov, A. [INR, Moscow (Russian Federation)

1995-09-01T23:59:59.000Z

305

Biaxially-Textured Photovoltaic Film Crystal Silicon on Ion Beam Assisted Deposition CaF2 Seed Layers on Glass  

SciTech Connect

We grow biaxially textured heteroepitaxial crystal silicon (c-Si) films on display glass as a low-cost photovoltaic material. We first fabricate textured CaF{sub 2} seed layers using ion-beam assisted deposition, then coat the CaF{sub 2} with a thin, evaporated epitaxial Ge buffer and finally deposit heteroepitaxial silicon on the Ge. The silicon is grown by hot-wire chemical vapor deposition, a high-rate, scalable epitaxy technology. Electron and X-ray diffraction confirm the biaxial texture of the CaF{sub 2} and epitaxial growth of the subsequent layers. Transmission electron microscopy reveals columnar silicon grains about 500 nm across. We fabricate a proof-of-concept epitaxial film c-Si solar cell with an open circuit voltage of 375 mV that is limited by minority carrier lifetime.

Groves, J. R.; Li, J. B.; Clemens, B. M.; LaSalvia, V.; Hasoon, F.; Branz, H. M.; Teplin, C. W.

2012-05-01T23:59:59.000Z

306

Preparation of diamond-like carbon and boron nitirde films by high-intensity pulsed ion beam deposition  

SciTech Connect

Intense ion beams (300-keV C{sup +}, O{sup +}, and H{sup +}, 20--30 kA, 50 to 400-ns pulsewidth, up to 0.3-Hz repetition rate) were used to prepare diamond-like carbon (DLC) and boron nitride (BN) films. Deposition rates of up to 25{plus_minus}5 nm/pulse were obtained with instantaneous rates exceeding 1 mm/s. Most films were uniform, light brown, translucent, and nonporous with some micron-size particulates. Raman and parallel electron energy loss spectroscopy indicated the presence of DLC. The films possessed favorable electron field-emission characteristics desirable for cold-cathode displays. Transmission electron microscopy (TEM) and transmission electron diffraction (TED) revealed that the C films contained diamond crystals with 25 to 125-nm grain size. BN films were composed of hexagonal, cubic and wurtzite phases.

Rej, D.J.; Davis, H.A. [Los Alamos National Lab., NM (United States); Remnev, G.E. [Tomsk Polytechnic Univ., Tomsk (Russian Federation). Nuclear Physics Institute.] [and others

1995-05-01T23:59:59.000Z

307

Electrochemical Behavior of Disposable Electrodes Prepared by Ion Beam Based Surface Modification for Biomolecular Recognition  

SciTech Connect

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.

Erdem, A.; Karadeniz, H.; Caliskan, A. [Analytical Chemistry Department, Ege University, Faculty of Pharmacy, Bornova, Izmir 35100 (Turkey); Urkac, E. Sokullu; Oztarhan, A. [Bioengineering Department, Ege University, Bornova, Izmir 35100 (Turkey); Oks, E.; Nikolayev, A. [High Current Electronics, Institute, Tomsk (Russian Federation)

2009-03-10T23:59:59.000Z

308

Conformal growth of Mo/Si multilayers on grating substrates using collimated ion beam sputtering  

SciTech Connect

Deposition of multilayers on saw-tooth substrates is a key step in the fabrication of multilayer blazed gratings (MBG) for extreme ultraviolet and soft x-rays. Growth of the multilayers can be perturbed by shadowing effects caused by the highly corrugated surface of the substrates, which results in distortion of the multilayer stack structure and degradation of performance of MBGs. To minimize the shadowing effects we used an ionbeam sputtering machine with a highly collimated atomic flux to deposit Mo/Si multilayers on saw-tooth substrates. The sputtering conditions were optimized by finding a balance between smoothening and roughening processes in order to minimize degradation of the groove profile in the course of deposition and at the same time to keep the interfaces of a multilayer stack smooth enough for high efficiency. An optimal value of energy of 200 eV for sputtering Kr{sup +} ions was found by deposition of test multilayers on flat substrates at a range of ion energies. Two saw-tooth substrates were deposited at energies of 200 eV and 700 eV for the sputtering ions. It was found that reduction of the ion energy improved the blazing performance of the MBG and resulted in a 40% gain in the diffraction efficiency due to better replication of the groove profile by the multilayer. As a result of the optimization performed, an absolute diffraction efficiency of 28.8% was achieved for the 2nd blaze order of the MBG with a groove density of 7350 lines/mm at a wavelength of 13.5 nm. Details of the growth behavior of the multilayers on flat and saw-tooth substrates are discussed in terms of the Linear Continuous Model of film growth.

Gawlitza, Peter; Cambie, Rossana; Dhuey, Scott; Gullikson, Eric; Warwick, Tony; Braun, Stefan; Yashchuk, Valeriy; Padmore, Howard

2012-01-23T23:59:59.000Z

309

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

SciTech Connect

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.

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

2013-01-28T23:59:59.000Z

310

Fuel ion ratio measurements in reactor relevant neutral beam heated fusion plasmas  

SciTech Connect

In this paper, we present a method to derive n{sub t}/n{sub d} using the ratio of the thermonuclear neutron emission to the beam-target neutron emission. We apply it to neutron spectroscopy data from the magnetic proton recoil spectrometer taken during the deuterium tritium experiment at JET. n{sub t}/n{sub d}-values obtained using neutron spectroscopy are in qualitative agreement with those from other diagnostics measuring the isotopic composition of the exhaust in the divertor.

Hellesen, C.; Eriksson, J.; Conroy, S.; Ericsson, G.; Skiba, M.; Weiszflog, M. [Department of Physics and Astronomy, Applied Nuclear Physics, Uppsala University, Uppsala (Sweden); Collaboration: JET-EFDA Contributors

2012-10-15T23:59:59.000Z

311

Creation of stable nanoconstrictions in metallic thin films via progressive narrowing by focused-ion-beam technique and in situ control of resistance  

Science Conference Proceedings (OSTI)

This work describes the use of focused-ion-beam for the fabrication of metallic nanoconstrictions on a Fe thin film with in situ monitoring of the structure's resistance. With this approach the sequential FIB steps that are used for the gradual narrowing ... Keywords: Conductance quantum G0, FIB patterning, Magnetoresistive thin films, Nanoconstriction

J. Vincenc Obo?a; J. M. de Teresa; R. Córdoba; A. Fernández-Pacheco; M. R. Ibarra

2009-04-01T23:59:59.000Z

312

High-brightness picosecond ion beam source based on BNL Terawatt CO2 laser: Proof-of-principle experiments  

Science Conference Proceedings (OSTI)

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.

Shkolnikov, Peter

2012-10-04T23:59:59.000Z

313

KeV Ion Beam Induced Surface Modification of SiC Hydrogen Sensor  

DOE Green Energy (OSTI)

Silicon carbide, a wide-bandgap semiconductor, is currently used to fabricate an efficient high temperature hydrogen sensor. When a palladium coating is applied on the exposed surface of silicon carbide, the chemical reaction between palladium and hydrogen produces a detectable change in the surface chemical potential. Rather than applying a palladium film, we have implanted palladium ions into the silicon face of 6H, n-type Sic samples. The implantation energies and fluences, as well as the results obtained by monitoring the current through the sample in the presence of hydrogen are included in this paper.

Muntele, C.I.; Ila, D.; Williams, E.K.; Poker, D.B.; Hensley, D.K.

1999-11-29T23:59:59.000Z

314

Ion source  

DOE Patents (OSTI)

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.

Leung, Ka-Ngo (Hercules, CA); Ehlers, Kenneth W. (Alamo, CA)

1984-01-01T23:59:59.000Z

315

Electron-Ion Collisions  

Science Conference Proceedings (OSTI)

... Since the ions are created and excited with the same beam of electrons, by changing the electron beam energy one can selectively exclude certain ...

2010-12-07T23:59:59.000Z

316

ESTIMATION OF RADIOLYTIC GAS GENERATION RATE FOR CYLINDRICAL RADIOACTIVE WASTE PACKAGES - APPLICATION TO SPENT ION EXCHANGE RESIN CONTAINERS  

DOE Green Energy (OSTI)

Radioactive waste packages containing water and/or organic substances have the potential to radiolytically generate hydrogen and other combustible gases. Typically, the radiolytic gas generation rate is estimated from the energy deposition rate and the radiolytic gas yield. Estimation of the energy deposition rate must take into account the contributions from all radionuclides. While the contributions from non-gamma emitting radionuclides are relatively easy to estimate, an average geometry factor must be computed to determine the contribution from gamma emitters. Hitherto, no satisfactory method existed for estimating the geometry factors for a cylindrical package. In the present study, a formulation was developed taking into account the effect of photon buildup. A prototype code, called PC-CAGE, was developed to numerically solve the integrals involved. Based on the selected dimensions for a cylinder, the specified waste material, the photon energy of interest and a value for either the absorption or attenuation coefficient, the code outputs values for point and average geometry factors. These can then be used to estimate the internal dose rate to the material in the cylinder and hence to calculate the radiolytic gas generation rate. Besides the ability to estimate the rates of radiolytic gas generation, PC-CAGE can also estimate the dose received by the container material. This is based on values for the point geometry factors at the surface of the cylinder. PC-CAGE was used to calculate geometry factors for a number of cylindrical geometries. Estimates for the absorbed dose rate in container material were also obtained. The results for Ontario Power Generation's 3 m3 resin containers indicate that about 80% of the source gamma energy is deposited internally. In general, the fraction of gamma energy deposited internally depends on the dimensions of the cylinder, the material within it and the photon energy; the fraction deposited increases with increasing dimensions of the cylinder and decreases with increasing photon energy.

Husain, A.; Lewis, Brent J.

2003-02-27T23:59:59.000Z

317

SUMMARY OF BEAM BEAM OBSERVATIONS DURING STORES IN RHIC.  

Science Conference Proceedings (OSTI)

During stores, the beam-beam interaction has a significant impact on the beam and luminosity lifetimes in RHIC. This was observed in heavy ion, and even more pronounced in proton collisions. Observations include measurements of beam-beam induced tune shifts, lifetime and emittance growth measurements with and without beam-beam interaction, and background rates as a function of tunes. In addition, RHIC is currently the only hadron collider in which strong-strong beam-beam effects can be seen. Coherent beam-beam modes were observed, and suppressed by tune changes. In this article we summarize the most important beam-beam observations made during stores so far.

FISCHER,W.

2003-05-19T23:59:59.000Z

318

Durability of Solar Reflective Materials with an Alumina Hard Coat Produced by Ion-Beam-Assisted Deposition: Preprint  

DOE Green Energy (OSTI)

A promising low-cost reflector material for solar concentrating power (CSP) generation is a silvered substrate protected by an alumina coating several microns thick. The alumina hard coat is deposited under high vacuum by ion-beam-assisted-deposition (IBAD). Samples of this material have been produced both by batch and continuous roll-coating processes. The substrate materials investigated were polyethylene terephthalate (PET), PET laminated to stainless-steel foil, and chrome-plated carbon steel strip. The advantage of steel strip compared to PET is that it withstands a higher process temperature and lowers the final product installation costs. In this paper, we compare the durability of batch and roll-coated reflective materials with an alumina deposition rate as high as 10 nm/s. In general, the durability of the samples is found to be excellent. Comparisons between accelerated and outdoor exposure testing results indicate that these front-surface mirrors are more susceptible to weather conditions not simulated by accelerated tests (i.e., rain, sleet, snow, etc.) than other types of solar reflectors. For long-term durability, edge protection will be necessary, and durability could be improved by the addition of an adhesion-promoting layer between the silver and alumina.

Kennedy, C. E.; Smilgys, R. V.

2002-10-01T23:59:59.000Z

319

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

Science Conference Proceedings (OSTI)

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.

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

2012-11-27T23:59:59.000Z

320

High intensity production of high and medium charge state uranium and other heavy ion beams with VENUS  

E-Print Network (OSTI)

is the first third generation source routinely operated atIntroduction Third generation ECR ion sources are designedfor 4 th generation ECR ion sources [9] . The VENUS

Leitner, Daniela; Galloway, Michelle L.; Loew, Timothy J.; Lyneis, Claude M.; Rodriguez, Ingrid Castro; Todd, Damon S.

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Triple Ion-Beam Studies of Radiation Damage Effects in a 316LN Austenitic Alloy for a High Power Spallation Neutron Source  

DOE Green Energy (OSTI)

Austenitic 316LN alloy was ion-irradiated using the unique Triple Ion Beam Facility (TIF) at ORNL to investigate radiation damage effects relevant to spallation neutron sources. The TIF was used to simulate significant features of GeV proton irradiation effects in spallation neutron source target materials by producing displacement damage while simultaneously injecting helium and hydrogen at appropriately high gas/dpa ratios. Irradiations were carried out at 80, 200, and 350 C using 3.5 MeV Fe{sup 2}, 360 keV He{sup +}, and 180 keV H{sup +} to accumulate 50 dpa by Fe, 10,000 appm of He, and 50,000 appm of H. Irradiations were also carried out at 200 C in single and dual ion beam modes. The specific ion energies were chosen to maximize the damage and the gas accumulation at a depth of {approx} 1 {micro}m. Variations in microstructure and hardness of irradiated specimens were studied using transmission electron microscopy (TEM) and a nanoindentation technique, respectively. TEM investigation yielded varying damage defect microstructures, comprising black dots, faulted and unfaulted loops, and a high number density of fine bubbles (typically less than 1 nm in diameter). With increasing temperature, faulted loops had a tendency to unfault, and bubble microstructure changed from a bimodal size distribution to a unimodal distribution. Triple ion irradiations at the three temperatures resulted in similar increases in hardness of approximately a factor of two. Individually, Fe and He ions resulted in a similar magnitude of hardness increase, whereas H ions showed only a very small effect. The present study has yielded microstructural information relevant to spallation neutron source conditions and indicates that the most important concern may be radiation induced hardening and associated ductility loss.

Lee, EH

2001-08-01T23:59:59.000Z

322

Determining the density dependence of the nuclear symmetry energy using heavy-ion reactions  

E-Print Network (OSTI)

We review recent progress in the determination of the subsaturation density behavior of the nuclear symmetry energy from heavy-ion collisions as well as the theoretical progress in probing the high density behavior of the symmetry energy in heavy-ion reactions induced by high energy radioactive beams. We further discuss the implications of these results for the nuclear effective interactions and the neutron skin thickness of heavy nuclei.

Lie-Wen Chen; Che Ming Ko; Bao-An Li; Gao-Chan Yong

2007-11-12T23:59:59.000Z

323

HIGH-ENERGY HEAVY-ION BEAMS AS IGNITERS FOR COMMERCIAL-SCALE INTERTIAL-FUSION POWER PLANTS  

E-Print Network (OSTI)

Nucl. Proceedings of the Brookhaven Workshop on Heavy IonOctober 17-21, 1977- Brookhaven National Laboratory Report (the physics of Argonne, Brookhaven, Lawrence Berkeley, and

Judd, D.L.

2011-01-01T23:59:59.000Z

324

H- ION FORMATION FROM A SURFACE CONVERSION TYPE ION SOURCE  

E-Print Network (OSTI)

Hydrogen tons and Beams (Brookhaven Nat. Lab. , Sept. 1977).Hydrogen Ions and Beams (Brookhaven Nat. Lab. , Sept. 1977).fi Presented at the Brookhaven National Laboratory Second

Leung, K.N.

2010-01-01T23:59:59.000Z

325

THE MECHANICAL DESIGN AND FABRICATION OF A CONVECTIVELY COOLED ION ACCELERATOR FOR CONTINUOUSLY OPERATING NEUTRAL BEAM SYSTEMS  

E-Print Network (OSTI)

100 kV 1. 5 sec Table 1. Grid heat loads as %beam power. Towith a central separation. Grid heat loading is the dominantsystem. To investigate grid heat loads on our grid designs

Paterson, J.A.

2012-01-01T23:59:59.000Z

326

Design, operational experiences and beam results obtained with the SNS H- ion source and LEBT at Berkeley Lab  

E-Print Network (OSTI)

of the LEBT Layout for SNS,” Paper MOD19,Linac 2000,Beam Transport Section for the SNS Front-End Systems,” Paper2000). 6. R. Keller for the SNS Front-End Systems team, “

Keller, R.; Thomae, R.; Stockli, M.; Welton, R.

2002-01-01T23:59:59.000Z

327

Recent developments of the ion sources at Tri University Meson Factory/Isotope Separator and ACcelerator Facility  

SciTech Connect

This paper describes the recent progresses concerning the on-line ion source at the Tri University Meson Factory/Isotope Separator and ACcelerator (TRIUMF/ISAC) Radioactive Ion-Beam Facility; description of the new design of the surface-ion-source for improved stability of the beam intensity, description of the transport path to the east target station at ISAC, description of the new brazing techniques that solved recurrent problems with water leaks on the target/ion source assembly in the vacuum system, finally, recent developments concerning the Forced Electron Beam Induced Arc Discharge (FEBIAD) ion source are reported. In particular, a study on the effect of the plasma chamber volume on the ionization efficiency was completed.

Bricault, P. G.; Ames, F.; Dombsky, M.; Labrecque, F.; Lassen, J.; Mjos, A.; Minor, G. [TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3 (Canada); Tigelhoefer, A. [TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3 (Canada); Department Of Physics, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada)

2012-02-15T23:59:59.000Z

328

The on-line charge breeding program at TRIUMF's Ion Trap For Atomic and Nuclear Science for precision mass measurements  

Science Conference Proceedings (OSTI)

TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN) constitutes the only high precision mass measurement setup coupled to a rare isotope facility capable of increasing the charge state of short-lived nuclides prior to the actual mass determination in a Penning trap. Recent developments around TITAN's charge breeder, the electron beam ion trap, form the basis for several successful experiments on radioactive isotopes with half-lives as low as 65 ms and in charge states as high as 22+.

Simon, M. C.; Eberhardt, B.; Jang, F.; Luichtl, M.; Robertson, D.; Chaudhuri, A.; Delheij, P.; Grossheim, A.; Kwiatkowski, A. A.; Mane, E.; Pearson, M. R.; Schultz, B. E. [TRIUMF, Vancouver, British Columbia V6T 2A3 (Canada); Bale, J. C. [TRIUMF, Vancouver, British Columbia V6T 2A3 (Canada); Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6 (Canada); Chowdhury, U. [TRIUMF, Vancouver, British Columbia V6T 2A3 (Canada); Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Ettenauer, S.; Gallant, A. T.; Dilling, J. [TRIUMF, Vancouver, British Columbia V6T 2A3 (Canada); Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z1 (Canada); Lennarz, A. [TRIUMF, Vancouver, British Columbia V6T 2A3 (Canada); Institut fuer Kernphysik, Westfaelische Wilhelms-Universitaet, D-48149 Muenster (Germany); Ma, T.; Andreoiu, C. [Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6 (Canada); and others

2012-02-15T23:59:59.000Z

329

Dual and Triple Ion-Beam Irradiations of Fe, Fe(Cr) and Fe(Cr)-ODS Final Report: IAEA SMoRE CRP  

DOE Green Energy (OSTI)

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.

Fluss, M J; Hsiung, L L; Marian, J

2011-11-20T23:59:59.000Z

330

Ion-molecule interactions in crossed-beams. [N/sup +/-H/sub 2/; F/sup +/-H; CO/sub 2//sup +/-D/sub 2/  

SciTech Connect

Interactions of the ions N/sup +/, F/sup +/, and CO/sub 2//sup +/ with H/sub 2/ and/or its isotopes were examined using the crossed-beam technique in the low (< 4 eV) initial relative energy. For the reaction N/sup +/(/sup 3/P) + H/sub 2/ ..-->.. NH/sup +/ + H, complex formation dominates up to 1.9 eV and a substantial interaction occurs between all collision partners up to 3.6 eV. The distribution of N/sup +/ scattered nonreactively from H/sub 2/ also showed a long-lived complex channel below 1.9 eV. The reaction F/sup +/(/sup 3/P) + H/sub 2/ ..-->..FH/sup +/ + H proceeded by a direct reaction mechanism at 0.20 to 1.07 eV. The reaction CO/sub 2//sup +/ + D/sub 2/ ..-->.. DCO/sub 2//sup +/ + D gives asymmetric product distributions at 0.27 eV and above, indicating a direct reaction mechanism. Results indicated that there are probably barriers in the exit channels for DCO/sub 2//sup +/, DCO/sup +/, and D/sub 2/O/sup +/ products. The electronic state distributions of the N/sup +/, F/sup +/, and CO/sub 2//sup +/ beams was investigated using beam attenuation and total luminescence techniques.

Hansen, S.G.

1980-09-01T23:59:59.000Z

331

Effects of the Ti/Al atomic ratio on the properties of gradient (Ti,Al)N films synthesized by ion beam assisted deposition  

SciTech Connect

Gradient (Ti,Al)N films were prepared on high speed steel (HSS) and Si (111) wafers by using two Ar{sup +} beams to sputter a titanium target and an aluminum target separately, and a third N{sup +} beam to simultaneously bombard the growing film to assist deposition. The effects of the Ti/Al atomic ratio in the films on properties such as hardness, stress, and adhesion strength were investigated systematically. The results indicated that both the hardness and the adhesion of gradient (Ti,Al)N films to steel substrates exhibited {open_quotes}peak{close_quotes} type changes with an increase of the Ti/Al atomic ratio, and a maximum hardness of 3780thinspkgfthinspmm{sup {minus}2} was reached at a Ti/Al ratio of 5.35. The compressive stress of gradient (Ti,Al)N films increased with increasing Al content in the films. It was found that extreme hardness, high adhesion strength and low stress gradient (Ti,Al)N films can be synthesized on low temperature HSS steel by using the ion beam assisted deposition process.

He, X.; Shu, L.; Xie, Z.W. [Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

1999-03-01T23:59:59.000Z

332

Improved charge breeding efficiency of light ions with an electron cyclotron resonance ion source  

SciTech Connect

The Californium Rare Isotope Breeder Upgrade is a new radioactive beam facility for the Argonne Tandem Linac Accelerator System (ATLAS). The facility utilizes a {sup 252}Cf fission source coupled with an electron cyclotron resonance ion source to provide radioactive beam species for the ATLAS experimental program. The californium fission fragment distribution provides nuclei in the mid-mass range which are difficult to extract from production targets using the isotope separation on line technique and are not well populated by low-energy fission of uranium. To date the charge breeding program has focused on optimizing these mid-mass beams, achieving high charge breeding efficiencies of both gaseous and solid species including 14.7% for the radioactive species {sup 143}Ba{sup 27+}. In an effort to better understand the charge breeding mechanism, we have recently focused on the low-mass species sodium and potassium which up to present have been difficult to charge breed efficiently. Unprecedented charge breeding efficiencies of 10.1% for {sup 23}Na{sup 7+} and 17.9% for {sup 39}K{sup 10+} were obtained injecting stable Na{sup +} and K{sup +} beams from a surface ionization source.

Vondrasek, R.; Kutsaev, Sergey [Argonne National Laboratory, Argonne, Illinois 60439 (United States); Delahaye, P.; Maunoury, L. [Grand Accelerateur National d'Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Blvd Henri Becquerel, 14076 Caen (France)

2012-11-15T23:59:59.000Z

333

The laser ion source trap for highest isobaric selectivity in online exotic isotope production  

Science Conference Proceedings (OSTI)

The improvement in the performance of a conventional laser ion source in the laser ion source and trap (LIST) project is presented, which envisages installation of a repeller electrode and a linear Paul trap/ion guide structure. This approach promises highest isobaric purity and optimum temporal and spatial control of the radioactive ion beam produced at an online isotope separator facility. The functionality of the LIST was explored at the offline test separators of University of Mainz (UMz) and ISOLDE/CERN, using the UMz solid state laser system. Ionization efficiency and selectivity as well as time structure and transversal emittance of the produced ion beam was determined. Next step after complete characterization is the construction and installation of the radiation-hard final trap structure and its first online application.

Schwellnus, F.; Gottwald, T.; Mattolat, C.; Wendt, K. [Institut fuer Physik, Johannes Gutenberg-Universitaet, D-55099 Mainz (Germany); Blaum, K. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Catherall, R.; Crepieux, B.; Fedosseev, V.; Marsh, B.; Rothe, S.; Stora, T. [CERN, CH-1211 Geneva 23 (Switzerland); Kluge, H.-J. [GSI, Planckstrasse 1, D-64291 Darmstadt (Germany)

2010-02-15T23:59:59.000Z

334

Low energy spread ion source with a coaxial magnetic filter  

DOE Patents (OSTI)

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 radioactive ion beam production. The addition of a radially extending magnetic filter consisting of a pair of permanent magnets to the multicusp source reduces the energy spread considerably due to the improvement in the uniformity of the axial plasma potential distribution in the discharge region. A coaxial multicusp ion source designed to further reduce the energy spread utilizes a cylindrical magnetic filter to achieve a more uniform axial plasma potential distribution. The coaxial magnetic filter divides the source chamber into an outer annular discharge region in which the plasma is produced and a coaxial inner ion extraction region into which the ions radially diffuse but from which ionizing electrons are excluded. The energy spread in the coaxial source has been measured to be 0.6 eV. Unlike other ion sources, the coaxial source has the capability of adjusting the radial plasma potential distribution and therefore the transverse ion temperature (or beam emittance).

Leung, Ka-Ngo (Hercules, CA); Lee, Yung-Hee Yvette (Berkeley, CA)

2000-01-01T23:59:59.000Z

335

BOOSTER GOLD BEAM INJECTION EFFICIENCY AND BEAM LOSS  

SciTech Connect

The Relativistic Heavy Ion Collider (RHIC) at the BNL requires the AGS to provide Gold beam with the intensity of 10{sup 9} ions per bunch. Over the years, the Tandem Van de Graaff has provided steadily increasing intensity of gold ion beams to the AGS Booster. However, the gold beam injection efficiency at the Booster has been found to decrease with the rising intensity of injected beams. As the result, for Tandem beams of the highest intensity, the Booster late intensity is lower than with slightly lower intensity Tandem beam. In this article, the authors present two experiments associated with the Booster injection efficiency and beam intensity. One experiment looks at the Booster injection efficiency by adjusting the Tandem beam intensity, and another looks at the beam life time while scraping the beam in the Booster. The studies suggest that the gold beam injection efficiency at the AGS Booster is related to the beam loss in the ring, rather than the intensity of injected beam or circulating beam. A close look at the effect of the lost gold ion at the Booster injection leads to the prediction that the lost gold ion creates large number of positive ions, and even larger number of electrons. The lost gold beam is also expected to create large numbers of neutral particles. In 1998 heavy ion run, the production of positive ions and electrons due to the lost gold beam has been observed. Also the high vacuum pressure due to the beam loss, presumably because of the neutral particles it created, has been measured. These results will be reported elsewhere.

ZHANG,S.Y.; AHRENS,L.A.

1998-06-22T23:59:59.000Z

336

Particle beam injection system  

SciTech Connect

This invention provides a poloidal divertor for stacking counterstreaming ion beams to provide high intensity colliding beams. To this end, method and apparatus are provided that inject high energy, high velocity, ordered, atomic deuterium and tritium beams into a lower energy, toroidal, thermal equilibrium, neutral, target plasma column that is magnetically confined along an endless magnetic axis in a strong restoring force magnetic field having helical field lines to produce counterstreaming deuteron and triton beams that are received bent, stacked and transported along the endless axis, while a poloidal divertor removes thermal ions and electrons all along the axis to increase the density of the counterstreaming ion beams and the reaction products resulting therefrom. By balancing the stacking and removal, colliding, strong focused particle beams, reaction products and reactions are produced that convert one form of energy into another form of energy.

Jassby, Daniel L. (Princeton, NJ); Kulsrud, Russell M. (Princeton, NJ)

1977-01-01T23:59:59.000Z

337

RADIOACTIVE BATTERY  

DOE Patents (OSTI)

A radioactive battery which includes a capsule containing the active material and a thermopile associated therewith is presented. The capsule is both a shield to stop the radiations and thereby make the battery safe to use, and an energy conventer. The intense radioactive decay taking place inside is converted to useful heat at the capsule surface. The heat is conducted to the hot thermojunctions of a thermopile. The cold junctions of the thermopile are thermally insulated from the heat source, so that a temperature difference occurs between the hot and cold junctions, causing an electrical current of a constant magnitude to flow.

Birden, J.H.; Jordan, K.C.

1959-11-17T23:59:59.000Z

338

Real time x-ray studies during nanostructure formation on silicon via low energy ion beam irradiation using ultrathin iron films  

SciTech Connect

Real time grazing incidence small angle x-ray scattering and x-ray fluorescence (XRF) are used to elucidate nanodot formation on silicon surfaces during low energy ion beam irradiation of ultrathin iron-coated silicon substrates. Four surface modification stages were identified: (1) surface roughening due to film erosion, (2) surface smoothing and silicon-iron mixing, (3) structure formation, and (4) structure smoothing. The results conclude that 2.5 Multiplication-Sign 10{sup 15} iron atoms in a 50 nm depth triggers surface nanopatterning with a correlated nanodots distance of 25 nm. Moreover, there is a wide window in time where the surface can have correlated nanostructures even after the removal of all the iron atoms from the sample as confirmed by XRF and ex-situ x-ray photoelectron spectroscopy (XPS). In addition, in-situ XPS results indicated silicide formation, which plays a role in the structure formation mechanism.

El-Atwani, Osman [School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 (United States); Suslova, Anastassiya; Gonderman, Sean; Fowler, Justin; El-Atwani, Mohamad [School of Nuclear Engineering, Purdue University, West Lafayette, Indiana, 47907 (United States); DeMasi, Alexander; Ludwig, Karl [Physics Department, Boston University, Boston, Massachusetts 02215 (United States); Paul Allain, Jean [School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 (United States); School of Nuclear Engineering, Purdue University, West Lafayette, Indiana, 47907 (United States)

2012-12-24T23:59:59.000Z

339

Magnetically operated beam dump for dumping high power beams in a neutral beamline  

DOE Patents (OSTI)

It is an object of this invention to provide a beam dump system for a neutral beam generator which lowers the time-averaged power density of the beam dump impingement surface. Another object of this invention is to provide a beam dump system for a neutral particle beam based on reionization and subsequent magnetic beam position modulation of the beam onto a beam dump surface to lower the time-averaged power density of the beam dump ion impingement surface.

Dagenhart, W.K.

1984-01-27T23:59:59.000Z

340

Neutral particle beam intensity controller  

DOE Patents (OSTI)

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

Dagenhart, W.K.

1984-05-29T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Improved ion source  

DOE Patents (OSTI)

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,

Leung, K.N.; Ehlers, K.W.

1982-05-04T23:59:59.000Z

342

Radioactivity and Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Radioactivity and Radiation Radioactivity and Radiation Uranium and Its Compounds line line What is Uranium? Chemical Forms of Uranium Properties of Uranium Compounds Radioactivity and Radiation Uranium Health Effects Radioactivity and Radiation Discussion of radioactivity and radiation, uranium and radioactivity, radiological health risks of uranium isotopes and decay products. Radioactivity Radioactivity is the term used to describe the natural process by which some atoms spontaneously disintegrate, emitting both particles and energy as they transform into different, more stable atoms. This process, also called radioactive decay, occurs because unstable isotopes tend to transform into a more stable state. Radioactivity is measured in terms of disintegrations, or decays, per unit time. Common units of radioactivity

343

Neutral particle beam intensity controller  

DOE Patents (OSTI)

A neutral beam intensity controller is provided for a neutral beam generator in which a neutral beam is established by accelerating ions from an ion source into a gas neutralizer. An amplitude modulated, rotating magnetic field is applied to the accelerated ion beam in the gas neutralizer to defocus the resultant neutral beam in a controlled manner to achieve intensity control of the neutral beam along the beam axis at constant beam energy. The rotating magnetic field alters the orbits of ions in the gas neutralizer before they are neutralized, thereby controlling the fraction of neutral particles transmitted out of the neutralizer along the central beam axis to a fusion device or the like. The altered path or defocused neutral particles are sprayed onto an actively cooled beam dump disposed perpendicular to the neutral beam axis and having a central open for passage of the focused beam at the central axis of the beamline. Virtually zero therough 100% intensity control is achieved by varying the magnetic field strength without altering the ion source beam intensity or its species yield.

Dagenhart, William K. (Oak Ridge, TN)

1986-01-01T23:59:59.000Z

344

Booster gold beam injection efficiency and beam loss  

SciTech Connect

The Relativistic Heavy Ion Collider (RHIC) at the BNL requires the AGS to provide gold beam with the intensity of 10{sup 9} ions per bunch. Over the years, the Tandem Van de Graaff has provided steadily increasing intensity of gold ion beams to the AGS Booster. However, the gold ion beam injection efficiency at the Booster has been found to decrease with the rising intensity of injected beams. As the result, for Tandem beams of the highest intensity, the Booster late intensity is lower than with slightly lower intensity Tandem beam. In this article, the authors present two experiments associated with the Booster injection efficiency and beam intensity. One experiment looks at the Booster injection efficiency by adjusting the Tandem beam intensity, and another looks at the beam life time while scraping the beam in the Booster. The studies suggest that the gold beam injection efficiency at the AGS Booster is related to the beam loss in the ring, rather than the intensity of injected beam or circulating beam.

Zhang, S.Y.; Ahrens, L.A.

1998-08-01T23:59:59.000Z

345

Proceedings of the 10th international workshop on ECR ion sources  

SciTech Connect

This report contains papers on the following topics: Recent Developments and Future Projects on ECR Ion Sources; Operation of the New KVI ECR Ion Source at 10 GHz; Operational Experience and Status of the INS SF-ECR Ion Source; Results of the New ECR4'' 14.5 GHz ECRIS; Preliminary Performance of the AECR; Experimental Study of the Parallel and Perpendicular Particle Losses from an ECRIS Plasma; Plasma Instability in Electron Cyclotron Resonance Heated Ion Sources; The Hyperbolic Energy Analyzer; Status of ECR Source Development; The New 10 GHz CAPRICE Source; First Operation of the Texas A M ECR Ion Source; Recent Developments of the RIKEN ECR Ion Sources; The 14 GHz CAPRICE Source; Characteristics and Potential Applications of an ORNL Microwave ECR Multicusp Plasma Ion Source; ECRIPAC: The Production and Acceleration of Multiply Charged Ions Using an ECR Plasma; ECR Source for the HHIRF Tandem Accelerator; Feasibility Studies for an ECR-Generated Plasma Stripper; Production of Ion Beams by using the ECR Plasmas Cathode; A Single Stage ECR Source for Efficient Production of Radioactive Ion Beams; The Single Staged ECR Source at the TRIUMF Isotope Separator TISOL; The Continuous Wave, Optically Pumped H{sup {minus}} Source; The H{sup +} ECR Source for the LAMPF Optically Pumped Polarized Ion Source; Present Status of the Warsaw CUSP ECR Ion Source; An ECR Source for Negative Ion Production; GYRAC-D: A Device for a 200 keV ECR Plasma Production and Accumulation; Status Report of the 14.4 GHZ ECR in Legnaro; Status of JYFL-ECRIS; Report on the Uppsala ECRIS Facility and Its Planned Use for Atomic Physics; A 10 GHz ECR Ion Source for Ion-Electron and Ion-Atom Collision Studies; and Status of the ORNL ECR Source Facility for Multicharged Ion Collision Research.

Meyer, F W; Kirkpatrick, M I [eds.

1991-01-01T23:59:59.000Z

346

Beam History  

NLE Websites -- All DOE Office Websites (Extended Search)

Beam Status Beam History Print Beamline History Request Form To request a beam current histograph from the ALS storage ring beam histograph database, select the year, month, and...

347

Colliding Crystalline Beams  

SciTech Connect

Crystalline Beams* are an ordered state of an ensemble of ions, circulating in a storage ring, with very small velocity fluctuations. They can be obtained from ordinary warm ion beams with the application of powerful cooling techniques (stochastic, electron, laser, ...). Depending on the focussing properties and dimensions of the storage ring, and on the ion beam density, several ground states are possible. All of them can be visualized as a bundle of n{sub s} symmetrically distributed, parallel strings. The longitudinal ion separation {lambda} is the same for all strings. The minimum temperature that can be achieved depends on die background noise of the cooling technique used. It is required for stability that the vibration amplitude of the ions is only a fraction of the separation {lambda}.

Haffmans, A.F.; Maletic, D.; Ruggiero, A.G.

1995-06-01T23:59:59.000Z

348

Ion Sources - Cyclotron  

NLE Websites -- All DOE Office Websites (Extended Search)

Sources Sources The 88-Inch Cyclotron is fed by three Electron Cyclotron Resonance (ECR) high-charge-state ion sources, the ECR, the AECR, and VENUS, currently the most powerful ECR ion source in the world. Built to answer the demand for intense heavy ion beams, these high performance ion sources enable the 88-Inch Cyclotron to accelerate beams of ions from hydrogen to uranium. The ECR ion sources allow the efficient use of rare isotopes of stable elements, either from natural or enriched sources. A variety of metallic ion beams are routinely produced in our low temperature oven (up to 600°C) and our high temperature oven (up to 2100°C). Furthermore, the ability to produce "cocktails" (mixtures of beams) for the Berkeley Accelerator Space Effects (BASE) Facility adds tremendously to the flexibility of the 88-Inch Cyclotron.

349

Microfabrication of controlled-geometry samples for the laser-heated diamond-anvil cell using focused ion beam technology  

SciTech Connect

The pioneering of x-ray diffraction with in situ laser heating in the diamond-anvil cell has revolutionized the field of high-pressure mineral physics, expanding the ability to determine high-pressure, high-temperature phase boundaries and equations of state. Accurate determination of high-pressure, high-temperature phases and densities in the diamond-anvil cell rely upon collinearity of the x-ray beam with the center of the laser-heated spot. We present the development of microfabricated samples that, by nature of their design, will have the sample of interest in the hottest portion of the sample. We report initial successes with a simplified design using a Pt sample with dimensions smaller than the synchrotron-based x-ray spot such that it is the only part of the sample that absorbs the heating laser ensuring that the x-rayed volume is at the peak hotspot temperature. Microfabricated samples, synthesized using methods developed at The Ohio State University's Mineral Physics Laboratory and Campus Electron Optics Facility, were tested at high P-T conditions in the laser-heated diamond-anvil cell at beamline 16 ID-B of the Advanced Photon Source. Pt layer thicknesses of {le} 0.8 {micro}m absorb the laser and produce accurate measurements on the relative equations of state of Pt and PtC. These methods combined with high-purity nanofabrication techniques will allow for extension by the diamond-anvil cell community to multiple materials for high-precision high-pressure, high-temperature phase relations, equations of state, melting curves, and transport properties.

Pigott, Jeffrey S.; Reaman, Daniel M.; Panero, Wendy R. (OSU)

2012-02-06T23:59:59.000Z

350

Polarized negative ions  

SciTech Connect

This paper presents a survey of methods, commonly in use or under development, to produce beams of polarized negative ions for injection into accelerators. A short summary recalls how the hyperfine interaction is used to obtain nuclear polarization in beams of atoms. Atomic-beam sources for light ions are discussed. If the best presently known techniques are incorporated in all stages of the source, polarized H/sup -/ and D/sup -/ beams in excess of 10 ..mu..A can probably be achieved. Production of polarized ions from fast (keV) beams of polarized atoms is treated separately for atoms in the H(25) excited state (Lamb-Shift source) and atoms in the H(1S) ground state. The negative ion beam from Lamb-Shift sources has reached a plateau just above 1 ..mu..A, but this beam current is adequate for many applications and the somewhat lower beam current is compensated by other desirable characteristics. Sources using fast polarized ground state atoms are in a stage of intense development. The next sections summarize production of polarized heavy ions by the atomic beam method, which is well established, and by optical pumping, which has recently been demonstrated to yield very large nuclear polarization. A short discussion of proposed ion sources for polarized /sup 3/He/sup -/ ions is followed by some concluding remarks.

Haeberli, W.

1981-04-01T23:59:59.000Z

351

Selective Ion Source for Semiconductor Devices  

Berkeley National Laboratory's new selective ion source produces a beam of boron, arsenic or phosphorus ions from plasma that is essentially free of ...

352

Time-dependent, x-ray spectral unfolds and brightness temperatures for intense Li{sup +} ion beam-driven hohlraums  

SciTech Connect

X-ray-producing hohlraums are being studied as indirect drives for Inertial Confinement Fusion targets. In a 1994 target series on the PBFAII accelerator, cylindrical hohlraum targets were heated by an intense Li{sup +} ion beam and viewed by an array of 13 time-resolved, filtered x-ray detectors (XRDs). The UFO unfold code and its suite of auxiliary functions were used extensively in obtaining time- resolved x-ray spectra and radiation temperatures from this diagnostic. UFO was also used to obtain fitted response functions from calibration data, to simulate data from blackbody x-ray spectra of interest, to determine the suitability of various unfolding parameters (e.g., energy domain, energy partition, smoothing conditions, and basis functions), to interpolate the XRD signal traces, and to unfold experimental data. The simulation capabilities of the code were useful in understanding an anomalous feature in the unfolded spectra at low photon energies ({le} 100 eV). Uncertainties in the differential and energy-integrated unfolded spectra were estimated from uncertainties in the data. The time-history of the radiation temperature agreed well with independent calculations of the wall temperature in the hohlraum.

Fehl, D.L.; Chandler, G.A.; Biggs, F.; Dukart, R.J.; Moats, A.R.; Leeper, R.J.

1996-07-01T23:59:59.000Z

353

Time-dependent, x-ray spectral unfolds and brightness temperatures for intense Li{sup +} ion beam-driven hohlraums  

SciTech Connect

X-ray-producing hohlraums are being studied as indirect drives for inertial confinement fusion targets. In a 1994 target series on the PBFAII accelerator, cylindrical hohlraum targets were heated by an intense Li{sup +} ion beam and viewed by an array of 13 time-resolved, filtered x-ray detectors (XRDs). The unfold operator (UFO) code and its suite of auxiliary functions were used extensively in obtaining time-resolved x-ray spectra and radiation temperatures from this diagnostic. The UFO was also used to obtain fitted response functions from calibration data, to simulate data from blackbody x-ray spectra of interest, to determine the suitability of various unfolding parameters (e.g., energy domain, energy partition, smoothing conditions, and basis functions), to interpolate the XRD signal traces, and to unfold experimental data. The simulation capabilities of the code were useful in understanding an anomalous feature in the unfolded spectra at low photon energies ({le}100 eV). Uncertainties in the differential and energy-integrated unfolded spectra were estimated from uncertainties in the data. The time{endash}history of the radiation temperature agreed well with independent calculations of the wall temperature in the hohlraum. {copyright} {ital 1997 American Institute of Physics.}

Fehl, D.L.; Chandler, G.A.; Biggs, F.; Dukart, R.J.; Moats, A.R.; Leeper, R.J. [Sandia National Laboratories Albuquerque, New Mexico 87185 (United States)] [Sandia National Laboratories Albuquerque, New Mexico 87185 (United States)

1997-01-01T23:59:59.000Z

354

Effect of O{sub 2}{sup +}, H{sub 2}{sup +}+ O{sub 2}{sup +}, and N{sub 2}{sup +}+ O{sub 2}{sup +} ion-beam irradiation on the field emission properties of carbon nanotubes  

Science Conference Proceedings (OSTI)

The effect of O{sub 2}{sup +}, H{sub 2}{sup +}+ O{sub 2}{sup +}, and N{sub 2}{sup +}+ O{sub 2}{sup +} ion-beam irradiation of carbon nanotubes (CNTs) films on the chemical and electronic properties of the material is reported. The CNTs were grown by the chemical vapor deposition technique (CVD) on silicon TiN coated substrates previously decorated with Ni particles. The Ni decoration and TiN coating were successively deposited by ion-beam assisted deposition (IBAD) and afterwards the nanotubes were grown. The whole deposition procedure was performed in situ as well as the study of the effect of ion-beam irradiation on the CNTs by x-ray photoelectron spectroscopy (XPS). Raman scattering, field-effect emission gun scanning electron microscopy (FEG-SEM), and field emission (FE) measurements were performed ex situ. The experimental data show that: (a) the presence of either H{sub 2}{sup +} or N{sub 2}{sup +} ions in the irradiation beam determines the oxygen concentration remaining in the samples as well as the studied structural characteristics; (b) due to the experimental conditions used in the study, no morphological changes have been observed after irradiation of the CNTs; (c) the FE experiments indicate that the electron emission from the CNTs follows the Fowler-Nordheim model, and it is dependent on the oxygen concentration remaining in the samples; and (d) in association with FE results, the XPS data suggest that the formation of terminal quinone groups decreases the CNTs work function of the material.

Acuna, J. J. S.; Alvarez, F. [Instituto de Fisica 'Gleb Wataghin', UNICAMP, P.O. Box 6165 Campinas, SP, 13083-970 (Brazil); Escobar, M. [INQUIMAE, FCEyN-UBA-CONICET, Ciudad Universitaria, Pabellon II, Buenos Aires (Argentina); Depto. Fisica, FECyN, UBA, Ciudad Universitaria, Pabellon II, Buenos Aires (Argentina); Goyanes, S. N. [Depto. Fisica, FECyN, UBA, Ciudad Universitaria, Pabellon II, Buenos Aires (Argentina); Candal, R. J. [INQUIMAE, FCEyN-UBA-CONICET, Ciudad Universitaria, Pabellon II, Buenos Aires (Argentina); ECyT, 3iA, UNSAM, Campus Migueletes, San Martin, Pcia. Buenos Aires (Argentina); Zanatta, A. R. [Instituto de Fisica de Sao Carlos-USP, P.O. Box 369, Sao Carlos 13560-250 (Brazil)

2011-06-01T23:59:59.000Z

355

Radioactive waste systems and radioactive effluents  

SciTech Connect

Radioactive waste systems for handling gaseous, liquid, and solid wastes generated at light and pressurized water reactors are described. (TFD)

Row, T.H.

1973-01-01T23:59:59.000Z

356

Optimization of electron-cyclotron-resonance charge-breeder ions : Final CRADA Report.  

SciTech Connect

Measurements of 1+ beam properties and associated performance of ECR Charge Breeder source determined by total efficiency measurement and charge state distributions from the ECR Charge Breeder. These results were communicated to Far-Tech personnel who used them to benchmark the newly developed programs that model ion capture and charge breeding in the ECR Charge Breeder Source. Providing the basic data described above and in the discussion below to Far-Tech allowed them to improve and refine their calculational tools for ECR ion sources. These new tools will be offered for sale to industry and will also provide important guidance to other research labs developing Charge Breeding ion sources for radioactive beam physics research.

Pardo, R.; Physics; Far-Tech, Inc.

2009-10-09T23:59:59.000Z

357

Radioactivities in Solution by Particle Radiation can Increase Sister  

NLE Websites -- All DOE Office Websites (Extended Search)

Radioactivities in Solution by Particle Radiation can Increase Sister Radioactivities in Solution by Particle Radiation can Increase Sister Chromatid Exchanges Junko Maeda Colorado State University Abstract Introduction Non-radioactive atoms can become radioactive from a nuclear reaction when atoms are hit by other high energy particles. These radioactivations are observed in nuclear facilities and may result in health effects in humans. Protons, carbon-ions, and iron-ions are tested to verify this hypothesis. Materials and Methods Protons were accelerated to 70MeV in cyclotron (NIRS-930) at National Institute of Radiological Sciences (NIRS). Carbon-ions and iron-ions were accelerated to 290MeV/n and 500MeV/n respectively, in HIMAC (Heavy ion Medical Accelerator in Chiba) at NIRS. 60ml of sterilized Milli-Q ultra pure water or PBS were filled in Falcon T25 flasks and exposed to ionizing

358

Beam History  

NLE Websites -- All DOE Office Websites (Extended Search)

Beam History Print Beamline History Request Form To request a beam current histograph from the ALS storage ring beam histograph database, select the year, month, and day, then...

359

Synthesis of transactinide nuclei in cold fusion reactions using radioative beams  

E-Print Network (OSTI)

Chances of synthesis of transactinide nuclei in cold fusion reactions (one-neutron-out) reactions using radioactive beams are evaluated. Because intensities of radioactive beams are in most of the cases significantly lower than the ones of the stable beams, reactions with the highest radioactive beam intensities for the particular elements are considered. The results are compared with the recent ones obtained by Loveland who investigated the same nuclei.

Smolanczuk, Robert

2009-01-01T23:59:59.000Z

360

Synthesis of transactinide nuclei in cold fusion reactions using radioative beams  

E-Print Network (OSTI)

Chances of synthesis of transactinide nuclei in cold fusion reactions (one-neutron-out) reactions using radioactive beams are evaluated. Because intensities of radioactive beams are in most of the cases significantly lower than the ones of the stable beams, reactions with the highest radioactive beam intensities for the particular elements are considered. The results are compared with the recent ones obtained by Loveland who investigated the same nuclei.

Robert Smolanczuk

2009-12-04T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Negative ion source with low temperature transverse divergence optical system  

DOE Patents (OSTI)

A negative ion source is provided which has extremely low transverse divergence as a result of a unique ion focusing system in which the focal line of an ion beam emanating from an elongated, concave converter surface is outside of the ion exit slit of the source and the path of the exiting ions. The beam source operates with a minimum ion temperature which makes possible a sharply focused (extremely low transverse divergence) ribbon like negative ion beam.

Whealton, J.H.; Stirling, W.L.

1985-03-04T23:59:59.000Z

362

Ionic liquid ion sources as a unique and versatile option in FIB applications  

Science Conference Proceedings (OSTI)

This work discusses the potential applicability of point sources to focused ion beam (FIB) technology based on molten salts at room temperature, known as ionic liquid ion sources (ILIS). The beam shape and divergence angles for ILIS using the ionic liquid ... Keywords: Focused ion beam, High brightness, Ion etching, Ion source, Ionic liquid, Reactive ion

Carla Perez-Martinez; Stéphane Guilet; Jacques Gierak; Paulo Lozano

2011-08-01T23:59:59.000Z

363

Gas-Phase Ion Thermochemistry  

Science Conference Proceedings (OSTI)

... If the mobility of an ion in a gas ... ionization onset determination made with an electron beam where the energy spread of the electrons is broad ...

2013-07-15T23:59:59.000Z

364

Focused Ion Beam (Helios 650)  

Science Conference Proceedings (OSTI)

... The HNL650 is also equipped with retractable STEM detector, cryo stage, nano manipulator and multiple gas injection systems. ...

2012-10-01T23:59:59.000Z

365

OBSERVATION OF STRONG - STRONG AND OTHER BEAM - BEAM EFFECTS IN RHIC.  

SciTech Connect

RHIC is currently the only hadron collider in which strong-strong beam-beam effects can be seen. For the first time, coherent beam-beam modes were observed in a bunched beam hadron collider. Other beam-beam effects in RHIC were observed in operation and in dedicated experiments with gold ions, deuterons and protons. Observations include measurements of beam-beam induced tune shifts, lifetime and emittance growth measurements with and without beam-beam interaction, and background rates as a function of tunes. During ramps unequal radio frequencies in the two rings cause the crossing points to move longitudinally. Thus bunches experience beam-beam interactions only in intervals and the tunes are modulated. In this article we summarize the most important beam-beam observations made so far.

Fischer, W; Brennan, J M; Cameron, P; Connolly, R; Montag, C; Peggs, S; Pilat, F; Ptitsyn, V; Tepikian, S; Trbojevic, D

2003-05-12T23:59:59.000Z

366

BNL | ATF Beam Schedule  

NLE Websites -- All DOE Office Websites (Extended Search)

Beam Schedule (pdf) Beam Schedule (pdf) Sunday Monday Tuesday Wednesday Thursday Friday Saturday 22 1/2 Holiday Holiday 28 January Holiday 4 5 Maintenance 11 12 Maintenance 18 19 Holiday AE52 - DWFA (Euclid), BL2 25 February AE52 - DWFA (Euclid), BL2 1 2 AE50 - PWFA in QNR (UCLA), BL2 8 9 AE50 - PWFA in QNR (UCLA), BL2 15 16 Holiday AE50 - PWFA in QNR (UCLA), BL2 22 March 1 2 AE53 - Nonlinear Compton (UCLA) 8 9 AE53 - Nonlinear Compton (UCLA) 15 16 AE53 - Nonlinear Compton (UCLA) 22 23 29 Sunday Monday Tuesday Wednesday Thursday Friday Saturday User operations (E-beam in use) Ions - Ion generation User operations (laser in use) PWFA - Plasma Wakefield Acceleration User operations (E-beam and laser in use)

367

Midwestern Radioactive Materials Transportation Committee Agenda...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Midwestern Radioactive Materials Transportation Committee Agenda Midwestern Radioactive Materials Transportation Committee Agenda Midwestern Radioactive Materials Transportation...

368

Physics with Rare Isotope Beams  

Science Conference Proceedings (OSTI)

Using stable and radioactive beams provided by ATLAS nuclear reactions of special interest in astrophysics have been studied with emphasis on breakout from the hot CNO cycle to the rp-process. The masses of nuclear fragments provided by a strong fission source have been measured in order to help trace the path of the r process. 8Li ions produced by the d(7Li,8Li)n reaction have been trapped and the electrons and alphas emitted in the ensuing beta-decay measured. The neutrino directions were therefore determined, which leads to a measurement of the electron-neutrino correlation. The energies and kinematics are such that a sensitive search for any tensor admixture could be performed and an upper limit of 0.6% was placed on any such admixture. Earlier work on the electromagnetic form factors of the proton was extended. Graduate students were active participants in all of these eperiments, which formed the basis for six PhD theses.

Segel, Ralph E. [Northwestern University

2013-11-08T23:59:59.000Z

369

HEAVY ION INERTIAL FUSION  

E-Print Network (OSTI)

Accelerators as Drivers for Inertially Confined Fusion, W.B.LBL-9332/SLAC-22l (1979) Fusion Driven by Heavy Ion Beams,OF CALIFORNIA f Accelerator & Fusion Research Division

Keefe, D.

2008-01-01T23:59:59.000Z

370

Radioactive Waste Management (Minnesota)  

Energy.gov (U.S. Department of Energy (DOE))

This section regulates the transportation and disposal of high-level radioactive waste in Minnesota, and establishes a Nuclear Waste Council to monitor the federal high-level radioactive waste...

371

Radioactivity in consumer products  

SciTech Connect

Papers presented at the conference dealt with regulations and standards; general and biological risks; radioluminous materials; mining, agricultural, and construction materials containing radioactivity; and various products containing radioactive sources.

Moghissi, A.A.; Paras, P.; Carter, M.W.; Barker, R.F. (eds.)

1978-08-01T23:59:59.000Z

372

INTRA - BEAM SCATTERING MEASUREMENTS IN RHIC.  

DOE Green Energy (OSTI)

RHIC in gold operation shows significant intra-beam scattering due to the high charge state of the stored ions. Intra-beam scattering leads to longitudinal and transverse emittance growth. The longitudinal emittance growth causes debunching in operation; the transverse emittance growth contributes to the reduction of the beam and luminosity lifetimes. The longitudinal and transverse beam growth was measured. Beam growth measurement are compared with computations.

FISCHER,W.; CONNOLLY,R.; TEPIKIAN,S.; VAN ZEIJTS,J.; ZENO,K.

2002-06-02T23:59:59.000Z

373

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

E-Print Network (OSTI)

of the RIA or SNS beam lines. ..the Spallation Neutron Source (SNS) Front End [38,39,40] anddistributions. For example the SNS linac [38,166] or Rare

Prost, Lionel Robert

2007-01-01T23:59:59.000Z

374

Secondary ion collection and transport system for ion microprobe  

DOE Patents (OSTI)

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.

Ward, James W. (Canoga Park, CA); Schlanger, Herbert (Simi Valley, CA); McNulty, Jr., Hugh (Santa Monica, CA); Parker, Norman W. (Camarillo, CA)

1985-01-01T23:59:59.000Z

375

Dose and dose averaged LET comparison of {sup 1}H, {sup 4}He, {sup 6}Li, {sup 8}Be, {sup 10}B, {sup 12}C, {sup 14}N, and {sup 16}O ion beams forming a spread-out Bragg peak  

Science Conference Proceedings (OSTI)

Purpose: Modern clinical accelerators are capable of producing ion beams from protons up to neon. This work compares the depth dose distribution and corresponding dose averaged linear energy transfer (LET) distribution, which is related to the biological effectiveness, for different ion beams ({sup 1}H, {sup 4}He, {sup 6}Li, {sup 8}Be, {sup 10}B, {sup 12}C, {sup 14}N, and {sup 16}O) using multi-energetic spectra in order to configure spread-out Bragg peaks (SOBP). Methods: Monte Carlo simulations were performed in order to configure a 5 cm SOBP at 8 cm depth in water for all the different ion beams. Physical dose and dose averaged LET distributions as a function of depth were then calculated and compared. The superposition of dose distribution of all ions is also presented for a two opposing fields configuration. Additional simulations were performed for {sup 12}C beams to investigate the dependence of dose and dose averaged LET distributions on target depth and size, as well as beam configuration. These included simulations for a 3 cm SOBP at 7, 10, and 13 cm depth in water, a 6 cm SOBP at 7 depth in water, and two opposing fields of 6 cm SOBP. Results: Alpha particles and protons present superior physical depth dose distributions relative to the rest of the beams studied. Dose averaged LET distributions results suggest higher biological effectiveness in the target volume for carbon, nitrogen and oxygen ions. This is coupled, however, with relatively high LET values--especially for the last two ion species--outside the SOBP where healthy tissue would be located. Dose averaged LET distributions for {sup 8}Be and {sup 10}B beams show that they could be attractive alternatives to {sup 12}C for the treatment of small, not deeply seated lesions. The potential therapeutic effect of different ion beams studied in this work depends on target volume and position, as well as the number of beams used. Conclusions: The optimization of beam modality for specific tumor cites remains an open question that warrants further investigation and clinically relevant results.

Kantemiris, I.; Karaiskos, P.; Papagiannis, P.; Angelopoulos, A. [Nuclear and Particle Physics Section, Physics Department, University of Athens, Panepistimioupolis, Ilissia, 157 71 Athens (Greece) and Greek Atomic Energy Commission, Patriarxou Grigoriou Neapoleos, Agia Paraskevi, 15310 Athens (Greece); Medical Physics Laboratory, Medical School, University of Athens, 75 Mikras Asias, 115 27 Athens (Greece); Nuclear and Particle Physics Section, Physics Department, University of Athens, Panepistimioupolis, Ilissia, 157 71 Athens (Greece)

2011-12-15T23:59:59.000Z

376

Ultra-low-energy ion-beam-synthesis of Ge nanocrystals in thin ALD Al2O3 layers for memory applications  

Science Conference Proceedings (OSTI)

Structural and electrical properties of ALD-grown 5 and 7nm-thick Al"2O"3 layers before and after implantation of Ge ions (1keV, 0.5-1x10^1^6 cm^-^2) and thermal annealing at temperatures in the 700-1050^oC range are reported. Transmission Electron Microscopy ... Keywords: Ge nanocrystals, Ion implantation, Nanocrystal memory

P. Dimitrakis; A. Mouti; C. Bonafos; S. Schamm; G. Ben Assayag; V. Ioannou-Sougleridis; B. Schmidt; J. Becker; P. Normand

2009-07-01T23:59:59.000Z

377

Study of Ion Cooling and Ejection from Two Stage Linear Quadrupole Ion Trap consisted of RFQ ion guides  

NLE Websites -- All DOE Office Websites (Extended Search)

Ion Cooling and Ejection from Two Stage Linear Quadrupole Ion Trap consisted of RFQ ion guides Ion Cooling and Ejection from Two Stage Linear Quadrupole Ion Trap consisted of RFQ ion guides Kozlovskiy V.I., Filatov V. V., Shchepunov (UNIRIB, O.R.A.U. Oak Ridge, TN, USA) V. A., Brusov V. S., Pikhtelev A. R., Zelenov V. V. Introduction The primary objective of this work concerns linear quadrupole ion traps, which are commonly used to interface a continuous ion beam from an external source with a mass analyzer, requiring bunched or pulsed beams. We assume that the ions prepared for mass analysis, are well spatially shaped, and normalized by ion kinetic energy. (Slava, I don't understand the meaning of the previous sentence - I wrote it as I interpreted what you are saying - I may be all wrong) In our work, such a device was developed and built to interface a source of continuous ion beams and a

378

ION ACCELERATION SYSTEM  

DOE Patents (OSTI)

Well focused, intense ion beams are obtained by providing a multi- apertured source grid in front of an ion source chamber and an accelerating multi- apertured grid closely spaced from and in alignment with the source grid. The longest dimensions of the elongated apertures in the grids are normal to the direction of the magnetic field used with the device. Large ion currents may be withdrawn from the source, since they do not pass through any small focal region between the grids.

Luce, J.S.; Martin, J.A.

1960-02-23T23:59:59.000Z

379

Photodetachment of relativistic ions  

Science Conference Proceedings (OSTI)

A series of fundamental laser ion beam experiments has been made feasible by the high-quality, relativistic (..beta.. = 0.842) H/sup -/ ion beam available at the Clinton P. Anderson Meson Physics Facility (LAMPF). The relatavistic Doppler shift of the light from an ordinary ultraviolet laser provides what is, in effect, a continuously tunable vacuum-ultraviolet laser in the rest frame of the moving ions. The Lorentz transformation of a modest laboratory magnetic field provides an electric field of several megavolts/centimeter. The latest results of photo-detachment work with H/sup -/ beams and our spectroscopic work with H/sup 0/ beams are presented. Plans for future work are discussed.

Donahue, J.B.; Gram, P.A.M.; Hamm, M.E.; Hamm, R.W.; Bryant, H.C.; Butterfield, K.B.; Clark, D.A.; Frost, C.A.; Smith, W.W.

1980-01-01T23:59:59.000Z

380

ORNL radioactive waste operations  

SciTech Connect

Since its beginning in 1943, ORNL has generated large amounts of solid, liquid, and gaseous radioactive waste material as a by-product of the basic research and development work carried out at the laboratory. The waste system at ORNL has been continually modified and updated to keep pace with the changing release requirements for radioactive wastes. Major upgrading projects are currently in progress. The operating record of ORNL waste operation has been excellent over many years. Recent surveillance of radioactivity in the Oak Ridge environs indicates that atmospheric concentrations of radioactivity were not significantly different from other areas in East Tennesseee. Concentrations of radioactivity in the Clinch River and in fish collected from the river were less than 4% of the permissible concentration and intake guides for individuals in the offsite environment. While some radioactivity was released to the environment from plant operations, the concentrations in all of the media sampled were well below established standards.

Sease, J.D.; King, E.M.; Coobs, J.H.; Row, T.H.

1982-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Radioactive Waste Management Basis  

SciTech Connect

The purpose of this Radioactive Waste Management Basis is to describe the systematic approach for planning, executing, and evaluating the management of radioactive waste at LLNL. The implementation of this document will ensure that waste management activities at LLNL are conducted in compliance with the requirements of DOE Order 435.1, Radioactive Waste Management, and the Implementation Guide for DOE Manual 435.1-1, Radioactive Waste Management Manual. Technical justification is provided where methods for meeting the requirements of DOE Order 435.1 deviate from the DOE Manual 435.1-1 and Implementation Guide.

Perkins, B K

2009-06-03T23:59:59.000Z

382

WEB RESOURCE: Radioactive Waste  

Science Conference Proceedings (OSTI)

May 8, 2007 ... This resource offers a a very broad explanation of how the Belgian Agency for Management of Radioactive Waste and Enriched Fissile Material ...

383

SCAVENGING OF RADIOACTIVE AEROSOLS  

DOE Patents (OSTI)

A process of decontaminatinig an atmosphere from suspended radioactive particles by introducing silicon tetrafluoride whereby the particles precipitate and are removed, is described. (AEC)

Rosinski, J.; Werle, D.K.

1963-12-01T23:59:59.000Z

384

The Performance of the Gamma-Ray Energy Tracking In-Beam Nuclear Array GRETINA  

SciTech Connect

The Gamma-Ray Energy Tracking In-beam Nuclear Array (GRETINA) is a new generation high-resolution -ray spectrometer consisting of electrically segmented high-purity germanium crystals. GRETINA is capable of reconstructing the energy and position of each -ray interaction point inside the crystal with high resolution. This enables -ray energy tracking which in turn provides an array with large photopeak efficiency, high resolution and good peak-to-total ratio. GRETINA is used for nuclear structure studies with demanding -ray detection requirements and it is suitable for experiments with radioactive-ion beams with high recoil velocities. The GRETINA array has a 1 solid angle coverage and constitutes the first stage towards the full 4 array GRETA. We present in this paper the main parts and the performance of the GRETINA system.

Paschalis, S. [Lawrence Berkeley National Laboratory (LBNL); Lee, I. Y. [Lawrence Berkeley National Laboratory (LBNL); Macchiavelli, A. O. [Lawrence Berkeley National Laboratory (LBNL); Campbell, C. M. [Lawrence Berkeley National Laboratory, The Scripps Research Institite and The Skaggs Institute; Cromaz, M. [Lawrence Berkeley National Laboratory (LBNL); Gros, S. [Lawrence Berkeley National Laboratory (LBNL); Pavin, J. [Lawrence Berkeley National Laboratory (LBNL); Qian, J. [Lawrence Berkeley National Laboratory (LBNL); Clark, R. M. [Lawrence Berkeley National Laboratory (LBNL); Crawford, H. L. [Lawrence Berkeley National Laboratory (LBNL); Doering, D. [Lawrence Berkeley National Laboratory (LBNL); Fallon, P. [Lawrence Berkeley National Laboratory (LBNL); Lionberger, C. [Lawrence Berkeley National Laboratory (LBNL); Loew, T. [Lawrence Berkeley National Laboratory (LBNL); Petri, M. [Lawrence Berkeley National Laboratory (LBNL); Stezelberger, T. [Lawrence Berkeley National Laboratory (LBNL); Zimmerman, S. [Lawrence Berkeley National Laboratory (LBNL); Radford, David C [ORNL; Lagergren, Karin B [ORNL; Weisshaar, D. [Michigan State University, East Lansing; Winkler, R. [Michigan State University, East Lansing; Glasmacher, T. [Michigan State University, East Lansing; Anderson, J. T, [Argonne National Laboratory (ANL); Beausang, C. W. [University of Richmond

2013-01-01T23:59:59.000Z

385

Probing the Nuclear Symmetry Energy with Heavy-Ion Reactions Induced by Neutron-Rich Nuclei  

E-Print Network (OSTI)

Heavy-ion reactions induced by neutron-rich nuclei provide a unique means to investigate the equation of state of isospin-asymmetric nuclear matter, especially the density dependence of the nuclear symmetry energy. In particular, recent analyses of the isospin diffusion data in heavy-ion reactions have already put a stringent constraint on the nuclear symmetry energy around the nuclear matter saturation density. We review this exciting result and discuss its implications on nuclear effective interactions and the neutron skin thickness of heavy nuclei. In addition, we also review the theoretical progress on probing the high density behaviors of the nuclear symmetry energy in heavy-ion reactions induced by high energy radioactive beams.

Chen, Lie-Wen; Li, Bao-An; Yong, Gao-Chan

2007-01-01T23:59:59.000Z

386

Radioactive Nickel-63 - ORNL Neutron Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

Making Radioactive Nickel-63 Making Radioactive Nickel-63 ORNL-Supplied Nickel-63 Enables High-Sensitivity Explosives, Chemical Weapons, and Narcotics Detectors at Airports Explosives and narcotics detector. Detectors based on ion mobility spectrometry using ORNL 63Ni can now satisfy enhanced Homeland Security requirements at airports and other sensitive locations. When Transportation Security Administration (TSA) inspectors swipe a cloth over your luggage and then place it in an analyzer to check for explosives residue, they are using a device containing 63Ni, a radioactive isotope of nickel, made at ORNL. ORNL is the exclusive producer for 63Ni in North America and perhaps worldwide. "Our only competition would probably be Russia. They have high-flux research reactors and may well be supplying the material also,"

387

LASER BEAM PROFILE MONITOR DEVELOPMENT AT BNL FOR SNS.  

SciTech Connect

A beam profile monitor for H-beams based on laser photoneutralization is being developed at Brookhaven National Laboratory (BNL) for use on the Spallation Neutron Source (SNS) [l]. An H ion has a first ionization potential of 0.75eV and can be neutralized by light from a Nd:YAG laser (h=1064nm). To measure beam profiles, a narrow laser beam is passed through the ion beam neutralizing a portion of the H-beam struck by the laser. The laser trajectory is stepped across the ion beam. At each laser position, the reduction of the beam current caused by the laser is measured. A proof-of-principle experiment was done earlier at 750keV. This paper reports on measurements made on 200MeV beam at BNL and with a compact scanner prototype at Lawrence Berkeley National Lab on beam from the SNS RFQ.

CONNOLLY,R.; CAMERON,P.; CUPOLO,J.; GASSNER,D.; GRAU,M.; KESSELMAN,M.; PENG,S.; SIKORA,R.

2002-05-06T23:59:59.000Z

388

New beam instrumentation in the AGS Booster  

SciTech Connect

The AGS Booster was designed to accelerate beams from 2{times}10{sup 10} polarized protons to 1.5{times}10{sup 13} protons and heavy ions through Au{sup +33}. The range of beam parameters and the high vacuum, and radiation environment presented challenges for the beam instrumentation. Some interesting beam monitors in the Booster and transport lines, will be described. Where available, results will be presented. 21 refs., 7 figs.

Witkover, R.L.

1991-01-01T23:59:59.000Z

389

Radioactive waste disposal package  

DOE Patents (OSTI)

A radioactive waste disposal package comprising a canister for containing vitrified radioactive waste material and a sealed outer shell encapsulating the canister. A solid block of filler material is supported in said shell and convertible into a liquid state for flow into the space between the canister and outer shell and subsequently hardened to form a solid, impervious layer occupying such space.

Lampe, Robert F. (Bethel Park, PA)

1986-01-01T23:59:59.000Z

390

Characteristics of multiantenna rf ion source  

Science Conference Proceedings (OSTI)

We have developed a new multiantenna rf ion source for neutral beam injection and studied the effects of different antennas connected in parallel

T. Shoji; Y. Oka; NBI Group

2006-01-01T23:59:59.000Z

391

ION PULSE GENERATION  

DOE Patents (OSTI)

A device for generating ions in an ion source, forming the ions into a stream, deflecting the stream rapidly away from and back to its normal path along the axis of a cylindrical housing, and continually focusing the stream by suitable means into a sharp, intermittent beam along the axis is described. The beam exists through an axial aperture into a lens which focuses it into an accelerator tube. The ions in each burst are there accelerated to very high energies and are directed against a target placed in the high-energy end of the tube. Radiations from the target can then be analyzed in the interval between incidence of the bursts of ions on the target.

King, R.F.; Moak, C.D.; Parker, V.E.

1960-10-11T23:59:59.000Z

392

Noise reduction in negative-ion quadrupole mass spectrometry  

DOE Patents (OSTI)

This invention is comprised of a quadrupole mass spectrometer (QMS) system having an ion source, quadrupole mass filter, and ion collector/recorder system. A weak, transverse magnetic field and an electron collector are disposed between the quadrupole and ion collector. When operated in negative ion mode, the ion source produces a beam of primarily negatively-charged particles from a sample, including electrons as well as ions. The beam passes through the quadrupole and enters the magnetic field, where the electrons are deflected away from the beam path to the electron collector. The negative ions pass undeflected to the ion collector where they are detected and recorded as a mass spectrum.

Chastagner, P.

1991-12-31T23:59:59.000Z

393

MeV-ion beam analysis of the interface between filtered cathodic arc-deposited a-carbon and single crystalline silicon  

SciTech Connect

Amorphous carbon (a-C) films were deposited on Si(100) wafers by a filtered cathodicvacuum arc (FCVA) plasma source. A negative electrical bias was applied tothe silicon substrate in order to control the incident energy of carbon ions. Effects ofthe electrical bias on the a-C/Si interface characteristics were investigated by usingstandard Rutherford backscattering spectrometry (RBS) in the channeling modewith 2.1-MeV He2+ ions. The shape of the Si surface peaks of the RBS/channelingspectra reflects the degree of interface disorder due to atomic displacement fromthe bulk position of the Si crystal. Details of the analysis method developed aredescribed. It was found that the width of the a-C/Si interface increases linearlywith the substrate bias voltage but not the thickness of the a-C film.

Kamwanna, T.; Pasaja, N.; Yu, L.D.; Vilaithong, T.; Anders, A.; Singkarat, S.

2008-08-01T23:59:59.000Z

394

Proposal of physics with exotic beams at Oak Ridge  

SciTech Connect

A facility to produce proton-rich radioactive beams for nuclear structure and astrophysics experiments is proposed. This Oak Ridge Exotic Beam (OREB) facility is based on two existing accelerators. Beams of mass up to 80 can be accelerated to energies of about 5 MeV/nucleon. It will provide opportunities to study new areas in nuclear physics and astrophysics that are not available with the use of stable beams. 3 figs.

Lee, I-Yang.

1991-01-01T23:59:59.000Z

395

Physics of Neutralization of Intense Charged Particle Beam Pulses by a Background Plasma  

E-Print Network (OSTI)

Albuquerque, NM 87185 ion beam pulse can excite large-amplitude whistler waves, thereby producing a complex

Kaganovich, I.D.

2010-01-01T23:59:59.000Z

396

Field reversed ion rings  

DOE Green Energy (OSTI)

In typical field-reversed ion ring experiments, an intense annular ion beam is injected across a plasma-filled magnetic cusp region into a neutral gas immersed in a ramped solenoidal magnetic field. Assuming the characteristic ionization time is much shorter than the long ({ital t}{approx_gt}2{pi}/{Omega}{sub {ital i}}) beam evolution time scale, we investigate the formation of an ion ring in the background plasma followed by field reversal, using a 21/2-D hybrid, PIC code FIRE, in which the beam and background ions are treated as particles and the electrons as a massless fluid. We show that beam bunching and trapping occurs downstream in a ramped magnetic field for an appropriate set of experimental parameters. We find that a compact ion ring is formed and a large field reversal {zeta}={delta}{ital B}/{ital B}{approx_gt}1 on axis develops. We also observe significant deceleration of the ring on reflection due to the transfer of its axial momentum to the background ions, which creates favorable trapping conditions. {copyright} {ital 1995 American Institute of Physics.}

Sudan, R.N.; Omelchenko, Y.A. [Laboratory of Plasma Studies, Cornell University, Ithaca, New York 14853 (United States)

1995-09-01T23:59:59.000Z

397

Negative Halogen Ions for Fusion Applications  

DOE Green Energy (OSTI)

Over the past quarter century, advances in hydrogen negative ion sources have extended the usable range of hydrogen isotope neutral beams to energies suitable for large magnetically confined fusion devices. Recently, drawing upon this experience, negative halogen ions have been proposed as an alternative to positive ions for heavy ion fusion drivers in inertial confinement fusion, because electron accumulation would be prevented in negative ion beams, and if desired, the beams could be photo-detached to neutrals. This paper reports the results of an experiment comparing the current density and beam emittance of Cl+ and Cl- extracted from substantially ion-ion plasmas with that of Ar+ extracted from an ordinary electron-ion plasma, all using the same source, extractor, and emittance scanner. At similar discharge conditions, the Cl- current was typically 85 – 90% of the positive chlorine current, with an e-/ Cl- ratio as low as seven without grid magnets. The Cl- was as much as 76% of the Ar+ current from a discharge with the same RF drive. The minimum normalized beam emittance and inferred ion temperatures of Cl+, Cl-, and Ar+ were all similar, so the current density and optical quality of Cl- appear as suitable for heavy ion fusion driver applications as a positive noble gas ion of similar mass. Since F, I, and Br should all behave similarly in an ion source, they should also be suitable as driver beams.

Grisham, L.R.; Kwan, J.W.; Hahto, S.K.; Hahto, S.T.; Leung, K.N.; Westenskow, G.

2006-01-01T23:59:59.000Z

398

Radioactive Waste: 1. Radioactive waste from your lab is  

E-Print Network (OSTI)

Radioactive Waste: 1. Radioactive waste from your lab is collected by the RSO. 2. Dry radioactive waste must be segregated by isotope. 3. Liquid radioactive waste must be separated by isotope. 4. Liquid scintillation vials must be collected separately. 5. Any "mixed waste" must be cleared with the RSO and labeled

399

NEUTRAL BEAM INJECTOR RESEARCH AND DEVELOPMENT WORK IN THE USA  

E-Print Network (OSTI)

and development at the Brookhaven National Laboratory,Development of H" Sources at Brookhaven National Labora­Hydrogen Ions and Beams, Brookhaven National Labora­ tory,

Pyle, R.V.

2011-01-01T23:59:59.000Z

400

Radioactivity in Nature  

NLE Websites -- All DOE Office Websites (Extended Search)

Fig. 3-8. The ratio of uranium to lead present on Earth today gives us an estimate of its age (4.5 billion years). Given Earths age, any much shorter lived radioactive nuclei...

Note: This page contains sample records for the topic "radioactive ion beam" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Understanding radioactive waste  

SciTech Connect

This document contains information on all aspects of radioactive wastes. Facts are presented about radioactive wastes simply, clearly and in an unbiased manner which makes the information readily accessible to the interested public. The contents are as follows: questions and concerns about wastes; atoms and chemistry; radioactivity; kinds of radiation; biological effects of radiation; radiation standards and protection; fission and fission products; the Manhattan Project; defense and development; uses of isotopes and radiation; classification of wastes; spent fuels from nuclear reactors; storage of spent fuel; reprocessing, recycling, and resources; uranium mill tailings; low-level wastes; transportation; methods of handling high-level nuclear wastes; project salt vault; multiple barrier approach; research on waste isolation; legal requiremnts; the national waste management program; societal aspects of radioactive wastes; perspectives; glossary; appendix A (scientific American articles); appendix B (reference material on wastes). (ATT)

Murray, R.L.

1981-12-01T23:59:59.000Z

402

BEAM DIFFUSION MEASUREMENTS AT RHIC.  

Science Conference Proceedings (OSTI)

During a store, particles from the beam core continually diffuse outwards into the halo through a variety of mechanisms. Understanding the diffusion rate as a function of particle amplitude can help discover which processes are important to halo growth. A collimator can be used to measure the amplitude growth rate as a function of the particle amplitude. In this paper we present results of diffusion measurements performed at the Relativistic Heavy Ion Collider (RHIC) with fully stripped gold ions, deuterons, and protons. We compare these results with measurements from previous years, and simulations, and discuss any factors that relate to beam growth in RHIC.

FLILLER,R.P.,IIIDREES,A.GASSNER,D.MCINTYRE,G.PEGGS,S.TRBOJEVIC,D.

2003-05-12T23:59:59.000Z

403

Benchmarking Heavy Ion Transport Codes FLUKA, HETC-HEDS MARS15, MCNPX, and PHITS  

Science Conference Proceedings (OSTI)

Powerful accelerators such as spallation neutron sources, muon-collider/neutrino facilities, and rare isotope beam facilities must be designed with the consideration that they handle the beam power reliably and safely, and they must be optimized to yield maximum performance relative to their design requirements. The simulation codes used for design purposes must produce reliable results. If not, component and facility designs can become costly, have limited lifetime and usefulness, and could even be unsafe. The objective of this proposal is to assess the performance of the currently available codes � PHITS, FLUKA, MARS15, MCNPX, and HETC-HEDS � that could be used for design simulations involving heavy ion transport. We plan to access their performance by performing simulations and comparing results against experimental data of benchmark quality. Quantitative knowledge of the biases and the uncertainties of the simulations is essential as this potentially impacts the safe, reliable and cost effective design of any future radioactive ion beam facility. Further benchmarking of heavy-ion transport codes was one of the actions recommended in the �Report of the 2003 RIA R&D Workshop".

Ronningen, Reginald Martin [Michigan State University; Remec, Igor [Oak Ridge National Laboratory; Heilbronn, Lawrence H. [University of Tennessee-Knoxville

2013-06-07T23:59:59.000Z

404

Container for radioactive materials  

DOE Patents (OSTI)

A container for housing a plurality of canister assemblies containing radioactive material and disposed in a longitudinally spaced relation within a carrier to form a payload package concentrically mounted within the container. The payload package includes a spacer for each canister assembly, said spacer comprising a base member longitudinally spacing adjacent canister assemblies from each other and a sleeve surrounding the associated canister assembly for centering the same and conducting heat from the radioactive material in a desired flow path.

Fields, Stanley R. (Richland, WA)

1985-01-01T23:59:59.000Z

405

Dynamic radioactive particle source  

SciTech Connect

A method and apparatus for providing a timed, synchronized dynamic alpha or beta particle source for testing the response of continuous air monitors (CAMs) for airborne alpha or beta emitters is provided. The method includes providing a radioactive source; placing the radioactive source inside the detection volume of a CAM; and introducing an alpha or beta-emitting isotope while the CAM is in a normal functioning mode.

Moore, Murray E.; Gauss, Adam Benjamin; Justus, Alan Lawrence

2012-06-26T23:59:59.000Z

406

Ion photon emission microscope  

DOE Patents (OSTI)

An ion beam analysis system that creates microscopic multidimensional image maps of the effects of high energy ions from an unfocussed source upon a sample by correlating the exact entry point of an ion into a sample by projection imaging of the ion-induced photons emitted at that point with a signal from a detector that measures the interaction of that ion within the sample. The emitted photons are collected in the lens system of a conventional optical microscope, and projected on the image plane of a high resolution single photon position sensitive detector. Position signals from this photon detector are then correlated in time with electrical effects, including the malfunction of digital circuits, detected within the sample that were caused by the individual ion that created these photons initially.

Doyle, Barney L. (Albuquerque, NM)

2003-04-22T23:59:59.000Z

407

High current ion source  

DOE Patents (OSTI)

An ion source utilizing a cathode and anode for producing an electric arc therebetween. The arc is sufficient to vaporize a portion of the cathode to form a plasma. The plasma leaves the generation region and expands through another regon. The density profile of the plasma may be flattened using a magnetic field formed within a vacuum chamber. Ions are extracted from the plasma to produce a high current broad on beam.

Brown, Ian G. (1088 Woodside Rd., Berkeley, CA 94708); MacGill, Robert A. (645 Kern St., Richmond, CA 94805); Galvin, James E. (2 Commodore Dr. #276, Emeryville, CA 94608)

1990-01-01T23:59:59.000Z

408

Ion cyclotron resonance cell  

DOE Patents (OSTI)

An ion cyclotron resonance cell is disclosed having two adjacent sections separated by a center trapping plate. The first section is defined by the center trapping plate, a first end trapping plate, and excitation and detector electrodes. The second section includes a second end trapping plate spaced apart from the center plate, a mirror, and an analyzer. The analyzer includes a wavelength-selective light detector, such as a detector incorporating an acousto-optical device (AOD) and a photodetector. One or more ion guides, grounded plates with holes for the ion beam, are positioned within the vacuum chamber of the mass spectrometer between the ion source and the cell. After ions are trapped and analyzed by ion cyclotron resonance techniques in the first section, the ions of interest are selected according to their mass and passed into the second section for optical spectroscopic studies. The trapped ions are excited by light from a laser and caused thereby to fluoresce. The fluorescent light emitted by the excited ions is reflected by the mirror and directed onto the detector. The AOD is scanned, and the photodetector output is recorded and analyzed. The ions remain in the second section for an extended period, enabling multiple studies to be carried out on the same ensemble of ions. 5 figs.

Weller, R.R.

1995-02-14T23:59:59.000Z

409

Perspective on the Role of Negative Ions and Ion-Ion Plasmas in Heavy Ion Fusion Science, Magnetic Fusion Energy, and Related Fields  

DOE Green Energy (OSTI)

Some years ago it was suggested that halogen negative ions [1]could offer a feasible alternative path to positive ions as a heavy ion fusion driver beam which would not suffer degradation due to electron accumulation in the accelerator and beam transport system, and which could be converted to a neutral beam by photodetachment near the chamber entrance if desired. Since then, experiments have demonstrated that negative halogen beams can be extracted and accelerated away from the gas plume near the source with a surviving current density close to what could be achieved with a positive ion of similar mass, and with comparable optical quality. In demonstrating the feasibility of halogen negative ions as heavy ion driver beams, ion - ion plasmas, an interesting and somewhat novel state of matter, were produced. These plasmas, produced near the extractor plane of the sources, appear, based upon many lines of experimental evidence, to consist of almost equal densities of positive and negative chlorine ions, with only a small component of free electrons. Serendipitously, the need to extract beams from this plasma for driver development provides a unique diagnostic tool to investigate the plasma, since each component - positive ions, negative ions, and electrons -- can be extracted and measured separately. We discuss the relevance of these observations to understanding negative ion beam extraction from electronegative plasmas such as halogens, or the more familiar hydrogen of magnetic fusion ion sources. We suggest a concept which might improve negative hydrogen extraction by the addition of a halogen. The possibility and challenges of producing ion-ion plasmas with thin targets of halogens or, perhaps, salt, is briefly addressed.

Grisham, L.R.; Kwan, J.W.

2008-08-01T23:59:59.000Z

410

Radioactivity in food crops  

SciTech Connect

Published levels of radioactivity in food crops from 21 countries and 4 island chains of Oceania are listed. The tabulation includes more than 3000 examples of 100 different crops. Data are arranged alphabetically by food crop and geographical origin. The sampling date, nuclide measured, mean radioactivity, range of radioactivities, sample basis, number of samples analyzed, and bibliographic citation are given for each entry, when available. Analyses were reported most frequently for /sup 137/Cs, /sup 40/K, /sup 90/Sr, /sup 226/Ra, /sup 228/Ra, plutonium, uranium, total alpha, and total beta, but a few authors also reported data for /sup 241/Am, /sup 7/Be, /sup 60/Co, /sup 55/Fe, /sup 3/H, /sup 131/I, /sup 54/Mn, /sup 95/Nb, /sup 210/Pb, /sup 210/Po, /sup 106/Ru, /sup 125/Sb, /sup 228/Th, /sup 232/Th, and /sup 95/Zr. Based on the reported data it appears that radioactivity from alpha emitters in food crops is usually low, on the order of 0.1 Bq.g/sup -1/ (wet weight) or less. Reported values of beta radiation in a given crop generally appear to be several orders of magnitude greater than those of alpha emitters. The most striking aspect of the data is the great range of radioactivity reported for a given nuclide in similar food crops with different geographical origins.

Drury, J.S.; Baldauf, M.F.; Daniel, E.W.; Fore, C.S.; Uziel, M.S.

1983-05-01T23:59:59.000Z

411

Workshop on Accelerators for Heavy Ion Fusion Summary Report of the Workshop  

E-Print Network (OSTI)

W. M. Sharp, and D. R. Welch, Fusion Sci. Technol. 44, 266implosion in heavy ion fusion,"Laser Part. Beam 24, 359-Heavy-Ion-Beam Inertial Fusion at High Coupling Efficiency.

Seidl, P.A.

2013-01-01T23:59:59.000Z

412

Experimental Evaluation of a Negative Ion Source for a Heavy Ion Fusion Negative Ion Driver  

DOE Green Energy (OSTI)

Negative halogen ions have recently been proposed as a possible alternative to positive ions for heavy ion fusion drivers because electron accumulation would not be a problem in the accelerator, and if desired, the beams could be photo-detached to neutrals. To test the ability to make suitable quality beams, an experiment was conducted at Lawrence Berkeley National Laboratory using chlorine in an RF-driven ion source. Without introducing any cesium (which is required to enhance negative ion production in hydrogen ion sources) a negative chlorine current density of 45 mA/cm{sup 2} was obtained under the same conditions that gave 57 45 mA/cm{sup 2} of positive chlorine, suggesting the presence of nearly as many negative ions as positive ions in the plasma near the extraction plane. The negative ion spectrum was 99.5% atomic chlorine ions, with only 0.5% molecular chlorine, and essentially no impurities. Although this experiment did not incorporate the type of electron suppression technology that i s used in negative hydrogen beam extraction, the ratio of co-extracted electrons to Cl{sup -} was as low as 7 to 1, many times lower than the ratio of their mobilities, suggesting that few electrons are present in the near-extractor plasma. This, along with the near-equivalence of the positive and negative ion currents, suggests that the plasma in this region was mostly an ion-ion plasma. The negative chlorine current density was relatively insensitive to pressure, and scaled linearly with RF power. If this linear scaling continues to hold at higher RF powers, it should permit current densities of 100 45 mA/cm{sup 2}, sufficient for present heavy ion fusion injector concepts. The effective ion temperatures of the positive and negative ions appeared to be similar and relatively low for a plasma source.

L.R. Grisham, S.K. Hahto, S.T. Hahto, J.W. Kwan, and K.N. Leung

2004-06-16T23:59:59.000Z

413

Removal of radioactive and other hazardous material from fluid waste  

DOE Patents (OSTI)

Hollow glass microspheres obtained from fly ash (cenospheres) are impregnated with extractants/ion-exchangers and used to remove hazardous material from fluid waste. In a preferred embodiment the microsphere material is loaded with ammonium molybdophosphonate (AMP) and used to remove radioactive ions, such as cesium-137, from acidic liquid wastes. In another preferred embodiment, the microsphere material is loaded with octyl(phenyl)-N-N-diisobutyl-carbamoylmethylphosphine oxide (CMPO) and used to remove americium and plutonium from acidic liquid wastes.

Tranter, Troy J. (Idaho Falls, ID); Knecht, Dieter A. (Idaho Falls, ID); Todd, Terry A. (Aberdeen, ID); Burchfield, Larry A. (W. Richland, WA); Anshits, Alexander G. (Krasnoyarsk, RU); Vereshchagina, Tatiana (Krasnoyarsk, RU); Tretyakov, Alexander A. (Zheleznogorsk, RU); Aloy, Albert S. (St. Petersburg, RU); Sapozhnikova, Natalia V. (St. Petersburg, RU)

2006-10-03T23:59:59.000Z

414

Fragmentation of spherical radioactive heavy nuclei as a novel probe of transient effects in fission  

E-Print Network (OSTI)

Peripheral collisions with radioactive heavy-ion beams at relativistic energies are discussed as an innovative approach for probing the transient regime experienced by fissile systems evolving towards quasi-equilibrium. A dedicated experiment using the advanced technical installations of GSI, Darmstadt, permitted to realize ideal conditions for the investigation of relaxation effects in the meta-stable well. Combined with a highly sensitive experimental signature, it provides a measure of the transient effects with respect to the flux over the fission barrier. Within a two-step reaction process, 45 proton-rich unstable spherical isotopes produced by projectile-fragmentation of a stable 238U beam have been used as secondary projectiles. The fragmentation of the radioactive projectiles on lead results in nearly spherical compound nuclei which span a wide range in excitation energy and fissility. The decay of these excited systems by fission is studied with a dedicated set-up which permits the detection of both fission products in coincidence and the determination of their atomic numbers with high resolution. The width of the fission-fragment nuclear charge distribution is shown to be specifically sensitive to pre-saddle transient effects and is used to establish a clock for the passage of the saddle point. The comparison of the experimental results with model calculations points to a fission delay of (3.3+/-0.7).10-21s for initially spherical compound nuclei, independent of excitation energy and fissility. This value suggests a nuclear dissipation strength at small deformation of (4.5+/-0.5).1021s-1. The very specific combination of the physics and technical equipment exploited in this work sheds light on previous controversial conclusions.

C. Schmitt; K. -H. Schmidt; A. Keli?; A. Heinz; B. Jurado; P. N. Nadtochy

2010-04-07T23:59:59.000Z

415

Time-of-flight direct recoil ion scattering spectrometer  

DOE Patents (OSTI)

A time of flight direct recoil and ion scattering spectrometer beam line (10). The beam line (10) includes an ion source (12) which injects ions into pulse deflection regions (14) and (16) separated by a drift space (18). A final optics stage includes an ion lens and deflection plate assembly (22). The ion pulse length and pulse interval are determined by computerized adjustment of the timing between the voltage pulses applied to the pulsed deflection regions (14) and (16).

Krauss, Alan R. (Naperville, IL); Gruen, Dieter M. (Downers Grove, IL); Lamich, George J. (Orland Park, IL)

1994-01-01T23:59:59.000Z

416

Ion temperature via laser scattering on ion Bernstein waves  

DOE Green Energy (OSTI)

Hydrogen ion temperature has been measured in a warm toroidal plasma with externally launched ion Bernstein waves detected by heterodyne CO/sub 2/ laser scattering. Radial scanning of the laser beam allows precise determination of k/sub perpendicular to/ for the finite ion Larmor radius wave (..omega.. approx. less than or equal to 2..cap omega../sub i/). Knowledge of the magnetic field strength and ion concentration then give a radially resolved ion temperature from the dispersion relation. Probe measurements and Doppler broadening of ArII 4806A give excellent agreement.

Wurden, G.A.; Ono, M.; Wong, K.L.

1981-10-01T23:59:59.000Z

417

DETECTOR FOR RADIOACTIVE HYDROGEN  

SciTech Connect

A device of the Geiger-Mueller type is designed for detecting radioactive hydrogen in the presence of other radioactive substances. The device comprises an envelope with thin (1 to 5 mil thick) Ni or Pd windows at the ends, an anode and a cathode spaced apart in the envelope, and a counting gas within the envelope. In operation, the suspect atmosphere is blown against one of the windows, whereby only the hydrogen diffuses into the envelope for counting. Means is provided for heating the windows to the desired temperatures. (D.L.C.)

Christianson, C.; Gilman, M.; Maggio, R.C.

1963-12-10T23:59:59.000Z

418

Container for radioactive materials  

DOE Patents (OSTI)

A container is claimed for housing a plurality of canister assemblies containing radioactive material. The several canister assemblies are stacked in a longitudinally spaced relation within a carrier to form a payload concentrically mounted within the container. The payload package includes a spacer for each canister assembly, said spacer comprising a base member longitudinally spacing adjacent canister assemblies from each other and sleeve surrounding the associated canister assembly for centering the same and conducting heat from the radioactive material in a desired flow path. 7 figures.

Fields, S.R.

1984-05-30T23:59:59.000Z

419

ION PRODUCING MECHANISM  

DOE Patents (OSTI)

A calutron ion source is described which masks the ends of the arc to provide a more stable beam from the middle portion. The masking is effected by milling the arc slit in a single sheet of material which is secured to the open face of the arc block. (T.R.H.)

Oppenheimer, F.F.

1959-06-01T23:59:59.000Z

420

Production of high brightness H- beam by charge exchange of hydrogen atom beam in sodium jet  

DOE Green Energy (OSTI)

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.

Davydenko, V.; Zelenski, A.; Ivanov, A.; Kolmogorov, A.

2010-11-16T23:59:59.000Z

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421

Wide-range radioactive-gas-concentration detector  

DOE Patents (OSTI)

A wide-range radioactive-gas-concentration detector and monitor capable of measuring radioactive-gas concentrations over a range of eight orders of magnitude is described. The device is designed to have an ionization chamber sufficiently small to give a fast response time for measuring radioactive gases but sufficiently large to provide accurate readings at low concentration levels. Closely spaced parallel-plate grids provide a uniform electric field in the active region to improve the accuracy of measurements and reduce ion migration time so as to virtually eliminate errors due to ion recombination. The parallel-plate grids are fabricated with a minimal surface area to reduce the effects of contamination resulting from absorption of contaminating materials on the surface of the grids. Additionally, the ionization-chamber wall is spaced a sufficient distance from the active region of the ionization chamber to minimize contamination effects.

Anderson, D.F.

1981-11-16T23:59:59.000Z

422

TABLE OF RADIOACTIVE ELEMENTS.  

SciTech Connect

For those chemical elements which have no stable nuclides with a terrestrial isotopic composition, the data on radioactive half-lives and relative atomic masses for the nuclides of interest and importance have been evaluated and the recommended values and uncertainties are listed.

HOLDEN,N.E.

2001-06-29T23:59:59.000Z

423

RADIOACTIVITY (NATURAL) Synonyms Definition  

Science Conference Proceedings (OSTI)

rays to the natural dose of radioactivity is strongly depen- dent on altitude and ... a noble gas, and its migration in groundwater and soil gas is of ..... trometers available on the market. ... example, using an oil immersion objective (NA 1.4) with.

424

Accelerator and Beam Science, ABS, Accelerator Operations and Technology,  

NLE Websites -- All DOE Office Websites (Extended Search)

Accelerator Concepts Accelerator Concepts Injectors Operations Physics CONTACTS Group Leader Robert Garnett Deputy Group Leader Kenneth Johnson Office Administrator Monica Sanchez Phone: (505) 667-2846 Put a short description of the graphic or its primary message here Accelerator and Beam Science The Accelerator and Beam Science (AOT-ABS) Group at Los Alamos addresses physics aspects of the driver accelerator for the LANSCE spallation neutron source and related topics. These activities are wide ranging and include generating negative and positive ions in plasma ion sources, creating ion beams from these particles, accelerating the ion beams in linear accelerator structures up to an energy of 800 MeV, compressing the negative hydrogen beam to packets of sub-microsecond duration and accumulating beam current in the Proton Storage Ring, and

425

RADIOACTIVITY STORED UP BY ALGAE  

SciTech Connect

A fast radiometric method of measuring radioactivity uptake by marine organisms is described. (R.V.J.)

Akamsin, A.D.; Parchevskii, V.P.; Polikarpov, G.G.

1960-02-01T23:59:59.000Z

426

Beams 92: Proceedings. Volume 1: Invited papers, pulsed power  

Science Conference Proceedings (OSTI)

This report contains papers on the following topics: Ion beam papers; electron beam, bremsstrahlung, and diagnostics papers; radiating Z- pinch papers; microwave papers; electron laser papers; advanced accelerator papers; beam and pulsed power applications papers; pulsed power papers; and these papers have been indexed separately elsewhere.

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

1993-12-31T23:59:59.000Z

427

Method for calcining radioactive wastes  

DOE Patents (OSTI)

This invention relates to a method for the preparation of radioactive wastes in a low leachability form by calcining the radioactive waste on a fluidized bed of glass frit, removing the calcined waste to melter to form a homogeneous melt of the glass and the calcined waste, and then solidifying the melt to encapsulate the radioactive calcine in a glass matrix.

Bjorklund, William J. (Richland, WA); McElroy, Jack L. (Richland, WA); Mendel, John E. (Kennewick, WA)

1979-01-01T23:59:59.000Z

428

Introducing the Fission-Fusion Reaction Process: Using a Laser-Accelerated Th Beam to produce Neutron-Rich Nuclei towards the N=126 Waiting Point of the r Process  

E-Print Network (OSTI)

We propose to produce neutron-rich nuclei in the range of the astrophysical r-process around the waiting point N=126 by fissioning a dense laser-accelerated thorium ion bunch in a thorium target (covered by a CH2 layer), where the light fission fragments of the beam fuse with the light fission fragments of the target. Via the 'hole-boring' mode of laser Radiation Pressure Acceleration using a high-intensity, short pulse laser, very efficiently bunches of 232Th with solid-state density can be generated from a Th layer, placed beneath a deuterated polyethylene foil, both forming the production target. Th ions laser-accelerated to about 7 MeV/u will pass through a thin CH2 layer placed in front of a thicker second Th foil closely behind the production target and disintegrate into light and heavy fission fragments. In addition, light ions (d,C) from the CD2 production target will be accelerated as well to about 7 MeV/u, inducing the fission process of 232Th also in the second Th layer. The laser-accelerated ion bunches with solid-state density, which are about 10^14 times more dense than classically accelerated ion bunches, allow for a high probability that generated fission products can fuse again. In contrast to classical radioactive beam facilities, where intense but low-density radioactive beams are merged with stable targets, the novel fission-fusion process draws on the fusion between neutron-rich, short-lived, light fission fragments both from beam and target. The high ion beam density may lead to a strong collective modification of the stopping power in the target, leading to significant range enhancement. Using a high-intensity laser as envisaged for the ELI-Nuclear Physics project in Bucharest (ELI-NP), estimates promise a fusion yield of about 10^3 ions per laser pulse in the mass range of A=180-190, thus enabling to approach the r-process waiting point at N=126.

D. Habs; P. G. Thirolf; M. Gross; K. Allinger; J. Bin; A. Henig; D. Kiefer; W. Ma; J. Schreiber